publisher:("Helsinki University of Technology")

1. Karasmaa, Nina. The Transferability of Travel Demand Models. An Analysis of Transfer Methods, Data Quality and Model Estimation.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2003/isbn9512268574/

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The main goal of this study was to compare alternative methods of spatial transfer as a function of sample size, and identify the factors affecting… (more)

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The main goal of this study was to compare alternative methods of spatial transfer as a function of sample size, and identify the factors affecting the models quality and the impreciseness of the model parameters. In addition, different test measures for studying model transferability were compared and the applicability of the traditional statistical tests, with respect to those based on the prediction accuracy of sample enumeration tests and forecasts, were assessed. The research primarily concerned the transferability of mode and destination models; however, the preciseness of the trip generation level was considered as well. The study was mainly based on the mobility surveys conducted in the Helsinki Metropolitan Area (HMA) in 1995 and in the Turku region in 1997. The transferring procedures examined were Bayesian updating, combined transfer estimation, transfer scaling, and joint context estimation procedures. The trip groups studied were home-based work trips and other home-based trips. The studied modes were walk and bicycle, car and public transport. To explore the impact of sample size on transferring performance, model transferability was tested using three to four different sample sizes. Thus, all the transferability tests were made by using 100 bootstrap samples (resampled from the Turku 1997 dataset) for each trip group, transfer method and sample size category. The results indicated that joint context estimation gives the best prediction performance in almost all cases. In particular, the method is useful if the transfer bias is large or only some of the coefficients are precise. The applicability of joint context estimation can be improved by viewing the coefficients as variable-oriented and emphasizing precise and imprecise coefficients differently. The models transferred by using combined transfer estimation or transfer scaling were most sensitive to the sample size and their use, therefore, requires much larger samples than the Bayesian approach or joint context estimation. In addition, note that due to repeated measurements the results based on the Bayesian method and combined transfer estimation may be strongly biased. When defining the sample size required the fact that defining mode shares precisely may require more observations than the transferring mode and the destination choice models must be taken into account. The results also showed that statistical tests are not able to evaluate the goodness of transferred models with a high enough degree of versatility. For example two models that have totally different values for coefficients may have the same TTS. As a result, their ability to predict the effect of changes in a transportation system may differ greatly. On the whole, the differences between the best transfer methods are, in some cases, rather small, and the errors caused by the factors connected to the modelling and sample size seem to be larger than the errors caused by the model transfer itself.

Julkaisu / Teknillinen korkeakoulu, liikennetekniikka, ISSN 0781-5816; 106

Advisors/Committee Members: Helsinki University of Technology, Department of Civil and Environmental Engineering, Laboratory of Transportation Engineering.

Subjects/Keywords: transferability; travel demand model; mode choice; logit model

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APA (6^th Edition):

Karasmaa, N. (2004). The Transferability of Travel Demand Models. An Analysis of Transfer Methods, Data Quality and Model Estimation. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2003/isbn9512268574/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Karasmaa, Nina. “The Transferability of Travel Demand Models. An Analysis of Transfer Methods, Data Quality and Model Estimation.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2003/isbn9512268574/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Karasmaa, Nina. “The Transferability of Travel Demand Models. An Analysis of Transfer Methods, Data Quality and Model Estimation.” 2004. Web. 04 Mar 2021.

Vancouver:

Karasmaa N. The Transferability of Travel Demand Models. An Analysis of Transfer Methods, Data Quality and Model Estimation. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2003/isbn9512268574/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Karasmaa N. The Transferability of Travel Demand Models. An Analysis of Transfer Methods, Data Quality and Model Estimation. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2003/isbn9512268574/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. Forsström, Ulla. Interactions Between Base Paper and Coating Color in Metered Size Press Coating.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2003/isbn9512269112/

► The purpose of the thesis was to gain a greater understanding of the interactions between the base paper and coating color in the metered size… (more)

▼ The purpose of the thesis was to gain a greater understanding of the interactions between the base paper and coating color in the metered size press (MSP) nip. The effect of base paper in precoating with an MSP was investigated using mill woodfree base papers, laboratory sheets, pilot base papers and non-porous materials. The coating color formulations consisted of commercial raw materials, in most cases latex-CMC colors with a pigment mixture of CaCO3 and kaolin. Coating studies were carried out at 1000 m / min with a pilot-scale MSP coater. The coating layer formation on woodfree base paper in MSP precoating depended mainly on the base paper surface openness. Lowering the base paper openness by raising the filler content, adding mechanical pulp or through more intensive refining of the chemical pulps resulted in lower coatweights, but better coating coverage. Base paper roughness, small-scale basis weight variation (beta formation) and surface chemical properties of the fibers (hydrophilic / hydrophobic) had no effect on precoating layer formation or coverage. Coating color liquid phase seemed to penetrate mainly into the voids between the fibers, because of the short contact time in the film transfer nip. SEM-BSE and LIPS coverage measuring methods were found to give similar results for the precoated surfaces. The LIPS coverage results were lower than the SEM-BSE results at low coatweights. This indicated that the SEM-BSE method found thinner coating layers to be covered. Low base paper surface openness and high filler content on the surface of the sheet reduced coating color penetration into the base paper structure and the coating color stayed on the surface better. Dense base papers with high filler contents gave better small-scale uniformity than porous base papers. The coating coverage was sensitive to base paper shadow marking, which was clearly seen as large-scale coverage non-uniformity. With base papers with less filler on the surface, coverage could still be increased by increasing coating color viscosity. Using higher levels of kaolin in the coating formula improved coverage, especially at low coatweights. The machine speed and nip load did not affect coating coverage. The color solids content had only a minor impact on coating coverage. Smaller differences in coverage two-sidedness were observed when both paper sides were coated simultaneously compared to the situation where only one side was coated. When the paper was coated using hard rolls, coating coverage depended largely on the pore size of the base paper. Coatweight was formed mainly through penetration, the result being a dense coating layer. With soft rolls coating layer formation occurred more by dewatering, in which case better coverage was obtained, albeit accompanied by a porous coating layer. The porous coating layer with good coverage was the result of filter cake formation in the film transfer nip. The main mechanism by which coating layer formation took place was pressure-induced penetration of bulk coating color or liquid phase… Advisors/Committee Members: Helsinki University of Technology, Department of Forest Products Technology.

Subjects/Keywords: base paper; porosity; pore size; formation; hydrophobic sizing; coating; coating colour; film coating; coating coverage; coating structure; unevenness

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APA (6^th Edition):

Forsström, U. (2004). Interactions Between Base Paper and Coating Color in Metered Size Press Coating. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2003/isbn9512269112/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Forsström, Ulla. “Interactions Between Base Paper and Coating Color in Metered Size Press Coating.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2003/isbn9512269112/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Forsström, Ulla. “Interactions Between Base Paper and Coating Color in Metered Size Press Coating.” 2004. Web. 04 Mar 2021.

Vancouver:

Forsström U. Interactions Between Base Paper and Coating Color in Metered Size Press Coating. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2003/isbn9512269112/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Forsström U. Interactions Between Base Paper and Coating Color in Metered Size Press Coating. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2003/isbn9512269112/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

3. Tois, Jan. Modifications of Carboxyindoles on Solid Phase.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2003/isbn9512268930/

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Different solid phase modifications were studied in order to develop new and simple routes for pharmaceutically interesting highly substituted carboxyindoles. A convenient method for the… (more)

Subjects/Keywords: carboxyindoles; solid phase synthesis; direct functionalization; Vilsmeier formylation; lithiation; bromination

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Tois, J. (2004). Modifications of Carboxyindoles on Solid Phase. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2003/isbn9512268930/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Tois, Jan. “Modifications of Carboxyindoles on Solid Phase.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2003/isbn9512268930/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Tois, Jan. “Modifications of Carboxyindoles on Solid Phase.” 2004. Web. 04 Mar 2021.

Vancouver:

Tois J. Modifications of Carboxyindoles on Solid Phase. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2003/isbn9512268930/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tois J. Modifications of Carboxyindoles on Solid Phase. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2003/isbn9512268930/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

4. Kyttä, Marketta. Children in Outdoor Contexts. Affordances and Independent Mobility in the Assessment of Environmental Child Friendliness.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2003/isbn9512268736/

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According to James J. Gibson, the concept of the affordance refers to the functionally significant properties of the environment, and provides a psychologically relevant means… (more)

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According to James J. Gibson, the concept of the affordance refers to the functionally significant properties of the environment, and provides a psychologically relevant means to analyze evolving child-environment relationships. Affordances operationalize the transactional approach. Thus the concept allows researchers to bring the material environment back into the realm of environmental psychology. The framework of ecological perceptual psychology, and in particular the concept of the affordance, was utilized in determining the criteria for child-friendly environments. An assessment model for a child-friendly environment was constructed, which comprises two central criteria for environmental child friendliness: children's possibilities for independent mobility and their opportunities to actualize affordances. By combining various degrees of these two criteria, four hypothetical types of environment were distinguished, Bullerby, Wasteland, Cell, and Glasshouse. The Bullerby type represents a child-friendly environment, as it allows a positive interactive cycle to develop between a child and the environment. In the Bullerby type sufficient possibilities for independent mobility enables to a child to discover environmental affordances. Actualized affordances for their part motivate the child to move around more in the environment, which creates more possibilities for new affordances to become actualized. The empirical results from the study of eight- and nine-year-old children indicated that the developed model was sensitive enough to assess the child friendliness of different communities in Finland and Belarus (Belorussia). All hypothesized environmental types appeared in the data. Each neighborhood had a unique combination of affordances and independent mobility in terms of the model. The Bullerby type of setting abounded in the Finnish communities. The Cell, Wasteland, and Glasshouse types of environment were the most common in the Belorussian data. In general, the proportion of Bullerby-type settings decreased and that of Glasshouse-type settings increased as the degree of urbanization rose. The two-dimensional assessment model presented here could be further developed so that it includes a third dimension such as, for example, the emotional value of affordances for children. At the same time an essential future challenge for ecological perceptual psychology, that of studying the motivational basis of affordances, could be met. As the transactional approach of environmental psychology allows for the integration of children's experiences with the material world, it provides information that can be used in the design and planning of child-friendly environments.

Yhdyskuntasuunnittelun tutkimus- ja koulutuskeskuksen julkaisuja / Teknillinen korkeakoulu. A, ISSN 1455-7789; 28

Advisors/Committee Members: Helsinki University of Technology, Department of Architecture, Centre for Urban and Regional Studies.

Subjects/Keywords: affordances; ecological psychology; children; child-friendly environment; Bullerby model

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APA (6^th Edition):

Kyttä, M. (2004). Children in Outdoor Contexts. Affordances and Independent Mobility in the Assessment of Environmental Child Friendliness. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2003/isbn9512268736/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kyttä, Marketta. “Children in Outdoor Contexts. Affordances and Independent Mobility in the Assessment of Environmental Child Friendliness.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2003/isbn9512268736/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kyttä, Marketta. “Children in Outdoor Contexts. Affordances and Independent Mobility in the Assessment of Environmental Child Friendliness.” 2004. Web. 04 Mar 2021.

Vancouver:

Kyttä M. Children in Outdoor Contexts. Affordances and Independent Mobility in the Assessment of Environmental Child Friendliness. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2003/isbn9512268736/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kyttä M. Children in Outdoor Contexts. Affordances and Independent Mobility in the Assessment of Environmental Child Friendliness. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2003/isbn9512268736/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

5. Pärssinen, Janne. Hydrodynamics of Low-Flux and High-Flux Circulating Fluidized Beds.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2002/isbn9512263319/

► The ongoing growth of world population and industrialization is increasing the primary energy demand, and also the need for transport fuels. The increasing carbon dioxide… (more)

▼ The ongoing growth of world population and industrialization is increasing the primary energy demand, and also the need for transport fuels. The increasing carbon dioxide and other emissions are fostering the political atmosphere to demand for a more sustainable development with more efficient usage of raw materials and resources. In order to improve some key processes in refineries, such as Fluidized Catalytic Cracking (FCC), a better understanding of high-flux flow hydrodynamics is necessary. FCC units are producing a large proportion of gasoline world-wide, and some other valuable products such as light olefins and light cycle oil. Nearly all FCC units in production utilize a riser reactor, where the solids (catalyst) circulation rate could range from 400 kg/m2s to 1,200 kg/m2s, and the superficial gas velocity from 6 m/s to 28 m/s. Therefore, it is surprising that nearly all studies of CFB pilot hydrodynamics have been carried out at low solids fluxes of less than 200 kg/m2s, whereas only a few limited but helpful studies are discussing higher solids fluxes of over 500 kg/m2s (Zhu and Bi, 1995). Such studies are regarded very useful for industrial processes and unit design, development and optimization. In comparison to those studies carried out in the dense suspension upflow (DSU) regime (Grace et al., 1999), this Thesis will discuss high-flux operations where the axial solids holdup profile is not flat and the cross-sectional solids concentration is clearly less than 10%-vol in the upper portion of the riser. Consequently, the operation has similarities to both DSU and fast fluidization (FF) flow regimes. Since the cross-sectional solids concentration is also low (<10%-vol) in the upper portion of industrial FCC risers, another aim is to provide a detailed image of the radial solids concentration profiles and their development toward the top of a high-flux riser. Since there is confusion of how and why DSU flow regime would occupy a riser, some fundamental reasons are discussed in detail. It is shown that to realize a high-density circulating fluidized-bed operation (HFCFB), a high-flux circulating fluidized-bed (HFCFB) operation is essential but not sufficient. For having some experience enclosed from a low-flux riser, paper I is discussing the low-flux riser hydrodynamics concerning especially the flow structure near to the column wall. Paper II and III present the solids concentration and particle velocity profiles and flow development in a long and high-flux riser. Paper IV goes on to define a novel concept of four longitudinal sections in a HFCFB riser (but not in a HFCFB riser). This concept may be a very useful fundamental aid for industrial modeling of HFCFB risers. Paper V presents some operating experience of a high-flux riser with a novel design in the solids feeding inlet. Paper VI is discussing the particle aggregation in a HFCFB riser. The collected data in papers II to VI are believed to be useful for several industrial applications since not much measured data existed under high-solids… Advisors/Committee Members: Helsinki University of Technology, Department of Mechanical Engineering.

Subjects/Keywords: circulating fluidized beds; riser; solids concentration; particle velocity

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Pärssinen, J. (2004). Hydrodynamics of Low-Flux and High-Flux Circulating Fluidized Beds. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2002/isbn9512263319/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Pärssinen, Janne. “Hydrodynamics of Low-Flux and High-Flux Circulating Fluidized Beds.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2002/isbn9512263319/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Pärssinen, Janne. “Hydrodynamics of Low-Flux and High-Flux Circulating Fluidized Beds.” 2004. Web. 04 Mar 2021.

Vancouver:

Pärssinen J. Hydrodynamics of Low-Flux and High-Flux Circulating Fluidized Beds. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2002/isbn9512263319/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pärssinen J. Hydrodynamics of Low-Flux and High-Flux Circulating Fluidized Beds. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2002/isbn9512263319/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

6. Tammela, Simo. Fiber Amplifiers, Directly Modulated Transmitters and a Ring Network Structure for Optical Communications.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269791/

► The three technologies that are considered the key elements in building a metropolitan area optical network are studied in this thesis. They are optical amplification,… (more)

▼ The three technologies that are considered the key elements in building a metropolitan area optical network are studied in this thesis. They are optical amplification, high-speed low cost transmitters and ring network structures. These studies concentrate on cost reduction of these three technologies thus enabling the use of optical networks in small customer base metropolitan areas. The research on optical amplification concentrated first on the solution doping process, at present the most used method for producing erbium doped fiber. It was found that separationing the soot growth and the sintering improved the uniformity of the porous layer. This made the homogeneity of the doping concentration in the fiber core better. The effects of index profile variations that arise from the non-ideal solution doping process were also simulated. In the search for a better doping method a new nanoparticle glass-forming process, the direct nanoparticle deposition, was developed. In this process the doping is done simultaneously with glass formation. Utilizing this new process it was possible to improve the uniformity of the doping resulting in higher usable doping levels and shorter erbium doped fiber lengths in the amplifiers. There were fewer limitations in the amplifier caused by optical non-linearities and polarization mode dispersion since shorter fiber lengths were needed. The double cladding fiber, which avoids the costly coupling of the pump laser into a single mode waveguide, was also studied. This pumping scheme was found to improve the inversion uniformity in the erbium doped fiber core thereby enhancing the power conversion efficiency for the long wavelength band amplifier. In characterizing the erbium doped fiber amplifier the gain and noise figure was measured with a temporal filter setup. It was made of simple, low cost components but yielded accurate measurements since the noise originating from the amplified spontaneous emission was measured at the signal wavelength. In the study of fiber amplifier controlling schemes the input power of the fiber amplifier was successfully used to regulate the pump laser. This feed-forward control scheme provides a simple, low cost control and managment system for the erbium doped fiber amplifier in metropolitan area network applications that require flexible adding and dropping of wavelength channels. The transmitter research focused on the DFB laser due to its simplicity and low cost structure. A solid state Fabry-Perot etalon made from double polished silicon chip was used as a frequency discriminator in the chirp analyser developed for the DFB lasers. This wavelength discriminator did not require repeated calibration or active stabilisation and was controled electrically enabling automatic measurements. The silicon Fabry-Perot etalon was also used for simultaneous spectral filtering and wavelength control of the laser. The usable dispersion limited transmission length was increased when the filter was used in conjunction with the directly modulated distributed feedback… Advisors/Committee Members: Helsinki University of Technology, Department of Electrical and Communications Engineering, Optoelectronics Laboratory.

Subjects/Keywords: optical networks; metropolitan area; optical amplification; erbium doped fiber

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Tammela, S. (2004). Fiber Amplifiers, Directly Modulated Transmitters and a Ring Network Structure for Optical Communications. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269791/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Tammela, Simo. “Fiber Amplifiers, Directly Modulated Transmitters and a Ring Network Structure for Optical Communications.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269791/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Tammela, Simo. “Fiber Amplifiers, Directly Modulated Transmitters and a Ring Network Structure for Optical Communications.” 2004. Web. 04 Mar 2021.

Vancouver:

Tammela S. Fiber Amplifiers, Directly Modulated Transmitters and a Ring Network Structure for Optical Communications. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269791/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tammela S. Fiber Amplifiers, Directly Modulated Transmitters and a Ring Network Structure for Optical Communications. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269791/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

7. Putkonen, Tiina. Preparation of Indole Alkaloids via 1,4-Dihydropyridine Stage or Cyano-Masked Iminium Intermediates.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512268612/

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Methods to synthesise substituted pyridine derivatives utilising 1,4-dihydropyridines were studied. Addition of nucleophiles to N-alkyl pyridinium salts and application of the products to alkaloid synthesis… (more)

Subjects/Keywords: indole alkaloids; 1,4-dihydropyridines; cyano-trapping

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APA (6^th Edition):

Putkonen, T. (2004). Preparation of Indole Alkaloids via 1,4-Dihydropyridine Stage or Cyano-Masked Iminium Intermediates. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512268612/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Putkonen, Tiina. “Preparation of Indole Alkaloids via 1,4-Dihydropyridine Stage or Cyano-Masked Iminium Intermediates.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512268612/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Putkonen, Tiina. “Preparation of Indole Alkaloids via 1,4-Dihydropyridine Stage or Cyano-Masked Iminium Intermediates.” 2004. Web. 04 Mar 2021.

Vancouver:

Putkonen T. Preparation of Indole Alkaloids via 1,4-Dihydropyridine Stage or Cyano-Masked Iminium Intermediates. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512268612/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Putkonen T. Preparation of Indole Alkaloids via 1,4-Dihydropyridine Stage or Cyano-Masked Iminium Intermediates. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512268612/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

8. Lylykangas, Mikko. Kinetic Modeling of Liquid-Phase Hydrogenation Reactions.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269139/

► Kinetic models are an essential part of modern computer simulation based process design. The goal of the work presented here was to develop models for… (more)

▼ Kinetic models are an essential part of modern computer simulation based process design. The goal of the work presented here was to develop models for two types of industrially important hydrogenation reactions, namely the hydrogenation of monoand diaromatic compounds and the hydrogenation of isooctenes. The studied reactions are important in the production of new, environmentally friendly fuels. Saturation of aromatics is needed to limit the undesired particle emissions in the exhaust gases of diesel engines, and isooctane could be used to replace methyl-tert-butyl ether (MTBE) in gasoline as an octane rating increasing component. The hydrogenation of aromatics was studied on a commercial Ni/Al2O3 catalyst using three model compounds: toluene, 1,2,3,4-tetrahydronaphthalene (tetralin), and naphthalene. The results showed that the first ring of the diaromatic compound (naphthalene) is considerably more reactive than the second, whereas the hydrogenation rate of the monoaromatic compounds (toluene and tetralin) is only slightly affected by the structure of the substituent. In addition, an inhibition effect induced by competitive adsorption was observed in the hydrogenation of multicomponent mixtures. The most reactive compound adsorbs most strongly on the catalyst and inhibits the other reactions. Hydrogenation was assumed to proceed by a mechanism of stepwise addition of dissociatively adsorbed hydrogen. Langmuir–Hinshelwood type rate equations were able to describe the reaction kinetics successfully, including the inhibition effect. The estimated adsorption parameters in the mixtures increased with reactivity (Ktoluene = 1.0 × 10−3 m3/mol, Ktetralin = 4.4 × 10−3 m3/mol, Knaphthalene = 7.8 × 10−3 m3/mol). Additionally, the estimated activation energies were in the physically meaningful range of 26-59 kJ/mol. The hydrogenation of the isooctenes 2,4,4-trimethyl-1-pentene (TMP-1) and 2,4,4-trimethyl-2-pentene (TMP-2) to "isooctane" (IO; 2,2,4-trimethylpentane) was examined on commercial Ni/Al2O3, Co/SiO2, and Pt/Al2O3 catalysts. Qualitatively, the hydrogenation proceeded in the same way on the different catalysts in that TMP-1 (terminal double bond) was more reactive than TMP-2 (internal double bond), isooctane was the sole product, and double bond isomerization did not play an important role under the conditions used. Kinetic models were formulated on the basis of the two-step Horiuti–Polanyi mechanism, assuming rate limitation by the first hydrogen insertion. The difference in the activities (Ni > Co > Pt) of the three catalysts was concluded to be due to the number of active sites because turnover frequencies (TOFs) were of the same order of magnitude. However, in some features, Pt was found to deviate from Ni and Co in the hydrogenation of TMP-1 and TMP-2. Activation energies were higher (Eapp,TMP-1 = 49 kJ/mol on Pt and 34-35 kJ/mol on Ni and Co; Eapp,TMP-2 = 65 kJ/mol on Pt and 43-49 kJ/mol on Ni and Co) and hydrogen adsorption equilibrium constants were larger by two orders of magnitude (KH = 38 × 10−4 m3/mol on… Advisors/Committee Members: Helsinki University of Technology, Department of Chemical Technology, Laboratory of Industrial Chemistry.

Subjects/Keywords: hydrogenation; liquid phase; aromatic compounds; alkenes; kinetic modeling; heterogeneous catalysts

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APA (6^th Edition):

Lylykangas, M. (2004). Kinetic Modeling of Liquid-Phase Hydrogenation Reactions. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269139/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lylykangas, Mikko. “Kinetic Modeling of Liquid-Phase Hydrogenation Reactions.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269139/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lylykangas, Mikko. “Kinetic Modeling of Liquid-Phase Hydrogenation Reactions.” 2004. Web. 04 Mar 2021.

Vancouver:

Lylykangas M. Kinetic Modeling of Liquid-Phase Hydrogenation Reactions. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269139/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lylykangas M. Kinetic Modeling of Liquid-Phase Hydrogenation Reactions. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269139/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

9. Airila, Markus. Chaos in High-Power High-Frequency Gyrotrons.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269171/

►

Gyrotron interaction is a complex nonlinear dynamical process, which may turn chaotic in certain circumstances. The emergence of chaos renders dynamical systems unpredictable and causes… (more)

▼

Gyrotron interaction is a complex nonlinear dynamical process, which may turn chaotic in certain circumstances. The emergence of chaos renders dynamical systems unpredictable and causes bandwidth broadening of signals. Such effects would jeopardize the prospect of advanced gyrotrons in fusion. Therefore, it is important to be aware of the possibility of chaos in gyrotrons. There are three different chaos scenarios closely related to the development of high-power gyrotrons: First, the onset of chaos in electron trajectories would lead to difficulties in the design and efficient operation of depressed potential collectors, which are used for efficiency enhancement. Second, the radio-frequency signal could turn chaotic, decreasing the output power and the spectral purity of the output signal. As a result, mode conversion, transmission, and absorption efficiencies would be reduced. Third, spatio-temporal chaos in the resonator field structure can set a limit for the use of large-diameter interaction cavities and high-order TE modes (large azimuthal index) allowing higher generated power. In this thesis, the issues above are addressed with numerical modeling. It is found that chaos in electron residual energies is practically absent in the parameter region corresponding to high efficiency. Accordingly, depressed collectors are a feasible solution also in advanced high-power gyrotrons. A new method is presented for straightforward numerical solution of the one-dimensional self-consistent time-dependent gyrotron equations, and the method is generalized to two dimensions. In 1D, a chart of gyrotron oscillations is calculated. It is shown that the regions of stationary oscillations, automodulation, and chaos have a complicated topology in the plane of generalized gyrotron variables. The threshold current for chaotic oscillations exceeds typical operating currents by a factor of ten. However, reflection of the output signal may significantly lower the threshold. 2D computations indicate that stationary single-mode operation of gyrotrons would be impossible if the azimuthal index is about 46 or larger, which is rather close to the presently used values. Moreover, electron beam misalignment can lower this critical value. Above the critical value, less favorable modes suppress the operating mode.

Helsinki University of Technology publications in engineering physics. A, ISSN 1459-7268; 825

Advisors/Committee Members: Helsinki University of Technology, Department of Engineering Physics and Mathematics, Advanced Energy Systems.

Subjects/Keywords: depressed collector; spatio-temporal chaos; microwave reflections; electron beam misalignment; modeling

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APA (6^th Edition):

Airila, M. (2004). Chaos in High-Power High-Frequency Gyrotrons. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269171/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Airila, Markus. “Chaos in High-Power High-Frequency Gyrotrons.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269171/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Airila, Markus. “Chaos in High-Power High-Frequency Gyrotrons.” 2004. Web. 04 Mar 2021.

Vancouver:

Airila M. Chaos in High-Power High-Frequency Gyrotrons. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269171/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Airila M. Chaos in High-Power High-Frequency Gyrotrons. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269171/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

10. Honkanen, Tuomo. Modelling Industrial Maintenance Systems and the Effects of Automatic Condition Monitoring.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512268167/

►

In this dissertation, industrial maintenance activities are researched from a systemic point of view. Maintenance is considered from the selected viewpoint as a control system… (more)

▼

In this dissertation, industrial maintenance activities are researched from a systemic point of view. Maintenance is considered from the selected viewpoint as a control system for controlling the reliability of machines in a process environment. The control takes place through communication of information. Thus, maintenance can also be considered as an information processing system. Therefore, the viewpoint also supports development of future maintenance information systems. The specific interest of the research is in modelling the effects of automatic condition monitoring systems enabled by embedded electronics and software in industrial machines. The research problem is to model maintenance systems and the effects of condition monitoring. Because the focus is on the maintenance systems, the research approach differs from the usual reliability engineering approaches, which focus on the reliability of mechanical systems. The applied methods are a literature study of the main reliability paradigms and the systems theory to derive a theory of maintenance systems. The theory is then applied by developing a UML knowledge model, an applied Gorry-Morton control activities model, a stochastic simulation model and a dynamic simulation model of the maintenance systems. Also, one additional simulation model is developed to study the effect of remote condition monitoring on the spare parts supply chain. The main results indicate that the subjective nature of failures, the available information about the machines as well as the repeatability of the maintenance actions are the most important factors in the maintenance system control. Also, correct selection of the maintenance system cost functions is critical in determining the applied maintenance policies. Condition monitoring increases observability of the states of the machines and therefore enables more effective maintenance systems with the help of condition-based maintenance. However, the effectiveness of condition-based maintenance depends on the accuracy of the monitoring and the coverage of the failure diagnosis. The failure patterns and the repeatability of the maintenance actions also contribute significantly to the effectiveness of condition-based maintenance. In spare parts supply chains, remote condition monitoring can be used to stabilise the supply chain variability and to reduce the supply chain sensitivity to random noise and sudden changes in the consumption.

Report / Helsinki University of Technology, Information and Computer Systems in Automation, ISSN 1456-0887; 10

Advisors/Committee Members: Helsinki University of Technology, Department of Automation and Systems Technology, Information and Computer Systems in Automation.

Subjects/Keywords: maintenance system; condition monitoring; condition-based maintenance; supply chain; information system

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Honkanen, T. (2004). Modelling Industrial Maintenance Systems and the Effects of Automatic Condition Monitoring. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512268167/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Honkanen, Tuomo. “Modelling Industrial Maintenance Systems and the Effects of Automatic Condition Monitoring.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512268167/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Honkanen, Tuomo. “Modelling Industrial Maintenance Systems and the Effects of Automatic Condition Monitoring.” 2004. Web. 04 Mar 2021.

Vancouver:

Honkanen T. Modelling Industrial Maintenance Systems and the Effects of Automatic Condition Monitoring. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512268167/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Honkanen T. Modelling Industrial Maintenance Systems and the Effects of Automatic Condition Monitoring. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512268167/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

11. Kärkkäinen, Mikko. Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269295/

►

Modeling of interfaces and layers with the finite-difference time-domain method (FDTD) is considered in this thesis. New numerical models are developed and verified. A surface… (more)

▼

Modeling of interfaces and layers with the finite-difference time-domain method (FDTD) is considered in this thesis. New numerical models are developed and verified. A surface impedance boundary condition relates the tangential electric and magnetic fields on an interface between two materials. The exact surface impedance uniquely defines the electromagnetic fields outside the material. The material structure is removed from the computational space. The resulting computational savings are huge in electrically large problems, like the modeling of coated targets in military applications. Using the surface impedance techniques in numerical methods is extremely reasonable when the reflection of electromagnetic fields from materials is difficult to compute directly. For example, if the wavelength inside the material under investigation is very small compared to the wavelength outside the material, the straightforward discretization of the fields inside the material is not a clever approach. The surface impedance boundary conditions may be utilized in such situations. In this thesis, a higher-order FDTD-model of interfaces with metals and semiconductors is developed and verified. As the most important new feature, the model takes arbitrary excitations into account in a general fashion using spatial derivatives on the interface. Novel techniques for modeling of dielectric layers on metal surfaces are also developed. Application of the surface impedance concept to derive analytical absorbing boundary conditions is also considered. An alternative and original model for electrically thin dispersive layers is introduced. Unusual electromagnetic properties of dispersive layers are numerically studied in the frequency range, where the real parts of material parameters are negative. Applications of the surface impedance concept to modeling of antennas with artificial electromagnetic materials are presented with numerical results for prototype devices.

Helsinki University of Technology Radio Laboratory publications. S, ISSN 1456-3835; 264

Advisors/Committee Members: Helsinki University of Technology, Department of Electrical and Communications Engineering, Radio Laboratory.

Subjects/Keywords: FDTD; surface impedance boundary condition; dielectric layer; surface impedance; absorbing boundary condition; metamaterial

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APA (6^th Edition):

Kärkkäinen, M. (2004). Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269295/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kärkkäinen, Mikko. “Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269295/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kärkkäinen, Mikko. “Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method.” 2004. Web. 04 Mar 2021.

Vancouver:

Kärkkäinen M. Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269295/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kärkkäinen M. Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269295/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

12. Hellsten, Antti. New Two-Equation Turbulence Model for Aerodynamics Applications.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269341/

►

Two-equation turbulence modelling for computational fluid dynamics and especially for analyses of high-lift aerodynamics applications is studied in depth in this thesis. Linear Boussinesq-type modelling… (more)

Subjects/Keywords: computational fluid dynamics; turbulence modelling; high-lift aerodynamics; k-omega model; explicit algebraic Reynolds stress model

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Hellsten, A. (2004). New Two-Equation Turbulence Model for Aerodynamics Applications. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269341/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hellsten, Antti. “New Two-Equation Turbulence Model for Aerodynamics Applications.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269341/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hellsten, Antti. “New Two-Equation Turbulence Model for Aerodynamics Applications.” 2004. Web. 04 Mar 2021.

Vancouver:

Hellsten A. New Two-Equation Turbulence Model for Aerodynamics Applications. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269341/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hellsten A. New Two-Equation Turbulence Model for Aerodynamics Applications. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269341/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

13. Haanpää, Harri. Constructing Certain Combinatorial Structures by Computational Methods.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269422/

►

Combinatorics is a branch of mathematics that generally deals with a finite or at most countably infinite set and collections of its subsets. These collections… (more)

▼

Combinatorics is a branch of mathematics that generally deals with a finite or at most countably infinite set and collections of its subsets. These collections must then satisfy certain criteria depending on the class of objects and the problem being considered. The most fundamental problem in combinatorics is the problem of existence: Does a combinatorial structure that satisfies the given requirements exist? In general, it is straightforward to verify that a proposed structure satisfies the required criteria, but finding a structure of the required type is difficult. If a structure of the required type exists, any method that constructs one is sufficient to settle the existence question. Two problems closely related to the existence problem are the enumeration problem – how many different combinatorial structures of the required type exist – and the optimization problem – which combinatorial structure of the required type is the best, judged by some criterion. A computer may be very useful in solving problems of the three types mentioned above. If it is suspected that a structure of the required kind exists, one may design a computer program to sample the space of possible structures until one that satisfies the criteria is found. To show the nonexistence of a structure, to enumerate the structures of a given kind, or to determine the best structure of a given kind, it is generally necessary to conduct a case-by-case analysis of all possible structures, which is a task for which a computer is especially suited. It is, however, often a nontrivial task to design an efficient algorithm for such an analysis. In this thesis several ways of applying computational methods to combinatorial problems are described. Tabu search on graphs with cyclic symmetry is used to obtain a lower bound for a Ramsey number, an orderly backtrack search with isomorph rejection is applied to a particular class of codes to classify certain designs and the whist tournaments with up to thirteen players, and another orderly search is used to obtain the optimal sum and difference packings and covers of small Abelian groups.

Research reports / Helsinki University of Technology, Laboratory for Theoretical Computer Science. A, ISSN 1457-7615; 89

Advisors/Committee Members: Helsinki University of Technology, Department of Computer Science and Engineering, Laboratory for Theoretical Computer Science.

Subjects/Keywords: balanced incomplete block design; difference cover; difference packing; isomorph rejection; orderly algorithm; Ramsey number; Sidon set; sum cover; sum packing; whist tournament

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Haanpää, H. (2004). Constructing Certain Combinatorial Structures by Computational Methods. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269422/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Haanpää, Harri. “Constructing Certain Combinatorial Structures by Computational Methods.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269422/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Haanpää, Harri. “Constructing Certain Combinatorial Structures by Computational Methods.” 2004. Web. 04 Mar 2021.

Vancouver:

Haanpää H. Constructing Certain Combinatorial Structures by Computational Methods. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269422/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Haanpää H. Constructing Certain Combinatorial Structures by Computational Methods. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269422/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

14. Kolehmainen, Mikko T. Data Exploration with Self-Organizing Maps in Environmental Informatics and Bioinformatics.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn951270000X/

►

The aim of this thesis was to evaluate the usability of self-organizing maps and some other methods of computational intelligence in analysing and modelling problems… (more)

▼

The aim of this thesis was to evaluate the usability of self-organizing maps and some other methods of computational intelligence in analysing and modelling problems of environmental informatics and bioinformatics. The concepts of environmental informatics, bioinformatics, computational intelligence and data mining are first defined. There follows an introduction to the data processing chain of knowledge discovery and the methods used in this thesis, namely linear regression, self-organizing maps (SOM), Sammon's mapping, U-matrix representation, fuzzy logic, c-means and fuzzy c-means clustering, multi-layer perceptron (MLP), and regularization and Bayesian techniques. The challenges posed by environmental processes and bioprocesses are then identified, including missing data problems, complex lagged dependencies among variables, non-linear chaotic dynamics, ill-defined inverse problems, and large search space in optimization tasks. The works included in this thesis are then evaluated and discussed. The results show that the combination of SOM and Sammon's mapping has great potential in data exploration, and can be used to reveal important features of the measurement techniques (e.g. separability of compounds), reveal new information about already studied phenomena, speed up research work, act as a hypothesis generator for traditional research, and supply clear and intuitive visualization of the environmental phenomenon studied. The results of regression studies show, as expected, that the MLP network yields better estimates in predicting future values of airborne pollutant concentration of NO2 compared with SOM based regression or the least squares approach using periodic components. Additionally, the use of local MLP models is shown to be slightly better for estimating future values of episodes compared with one MLP model only. However, it can be concluded in general that the architectural issues tested are not able to solve solely model performance problems. Finally, recommendations for future work are laid out. Firstly, the data exploration solution should be enhanced with methods from signal processing to enable the handling of measurements with different time scale and lagged multivariate time-series. The main suggestion, however, is to create an integrated environment for testing different hybrid schemes of computational intelligence for better time-series forecasting in environmental informatics and bioinformatics.

Kuopio University publications. C, Natural and environmental sciences, ISSN 1235-0486; 167

Advisors/Committee Members: Helsinki University of Technology, Department of Computer Science and Engineering, Laboratory of Computer and Information Science.

Subjects/Keywords: environmental science computing; biology computing; data analysis; data mining; knowledge acquisition; self-organising feature maps; neural nets

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kolehmainen, M. T. (2004). Data Exploration with Self-Organizing Maps in Environmental Informatics and Bioinformatics. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn951270000X/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kolehmainen, Mikko T. “Data Exploration with Self-Organizing Maps in Environmental Informatics and Bioinformatics.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn951270000X/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kolehmainen, Mikko T. “Data Exploration with Self-Organizing Maps in Environmental Informatics and Bioinformatics.” 2004. Web. 04 Mar 2021.

Vancouver:

Kolehmainen MT. Data Exploration with Self-Organizing Maps in Environmental Informatics and Bioinformatics. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn951270000X/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kolehmainen MT. Data Exploration with Self-Organizing Maps in Environmental Informatics and Bioinformatics. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn951270000X/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

15. Staffans, Aija. Vaikuttavat asukkaat. Vuorovaikutus ja paikallinen tieto kaupunkisuunnittelun haasteina.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512270242/

► The purpose of the research is to recognise the factors that influence the conflicts evoked by residents' participation. The formal participation and interaction is organised… (more)

▼ The purpose of the research is to recognise the factors that influence the conflicts evoked by residents' participation. The formal participation and interaction is organised in urban planning within the zoning process, but in practice, urban planning is influenced at least as much by different networks and the media that are outside the formal planning. This study examines the ways in which citizens can influence the planning process in an ever changing environment of formal and informal praxis. The conflicts are deconstructed through three questions: what is meant by the inhabitants' perspective in urban planning, how does the inhabitants' influencing take place in practice, and does the praxis of urban planning support the interaction and the so called shared expertise? The theoretical framework of the study is based on the concepts of planning and organisational theories. The key concept emerging from the theory of communicative planning is local knowledge and how it relates to urban planning as an institution. The interest of organisational theory in the construction of knowledge and the meeting of people in different kinds of networks has helped to analyse the conditions for knowledge creation in the planning process. The study approaches the research problem both theoretically and empirically. The residents' influencing of planning is connected to knowledge creation by describing, what urban planning knowledge from the perspective of the residents is like, how it can be influenced, how the residents produce knowledge themselves, and how they apply know how. The empirical material of the study has been gathered by taking part in the work of two citizen groups in Helsinki, during three years. Both groups have been active participants in urban planning; one of them in small-scale urban issues, the other in general planning issues. The study examines urban planning through the work and experiences of these two groups, and analyses through them the praxis of urban planning and the opportunities for residents to be active in urban matters. The residents in the study make through their activities visible several normative conceptions that prevail in urban planning, such as the comprehensiveness and innovativeness of planning, the possibilities of participation, and the objectivity of knowledge. Today, the praxis of urban planning does not sufficiently support the interaction between the citizens' local, place-based urban knowledge and that of planning expertise. The inhabitants' views remain as separate appendices to the planning documents. The inhabitants of the study began to transform their local views into explicit planning knowledge. During this process, they turned into professional "advocates of everyday life" whose influence was based on solid expertise. This expertise developed through the complex communicative networks and information flows that the inhabitants had created and nurtured. Influencing meant a strategic ability to compete in the production of knowledge according to context, either… Advisors/Committee Members: Helsinki University of Technology, Department of Architecture, Centre for Urban and Regional Studies.

Subjects/Keywords: urban planning; interaction; inhabitant participation; communicative planning theory; knowledge construction; local knowledge; planning knowledge; expertise; transmitting network; kaupunkisuunnittelu; vuorovaikutus; asukasosallistuminen; kommunikatiivinen suunnitteluteoria; tiedonrakennus; paikallinen tieto; suunnittelutieto; asiantuntijuus; välittäjäverkosto

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Staffans, A. (2004). Vaikuttavat asukkaat. Vuorovaikutus ja paikallinen tieto kaupunkisuunnittelun haasteina. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512270242/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Staffans, Aija. “Vaikuttavat asukkaat. Vuorovaikutus ja paikallinen tieto kaupunkisuunnittelun haasteina.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512270242/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Staffans, Aija. “Vaikuttavat asukkaat. Vuorovaikutus ja paikallinen tieto kaupunkisuunnittelun haasteina.” 2004. Web. 04 Mar 2021.

Vancouver:

Staffans A. Vaikuttavat asukkaat. Vuorovaikutus ja paikallinen tieto kaupunkisuunnittelun haasteina. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270242/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Staffans A. Vaikuttavat asukkaat. Vuorovaikutus ja paikallinen tieto kaupunkisuunnittelun haasteina. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270242/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

16. Bäckström, Tom. Linear Predictive Modelling of Speech – Constraints and Line Spectrum Pair Decomposition.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269473/

►

In an exploration of the spectral modelling of speech, this thesis presents theory and applications of constrained linear predictive (LP) models. Spectral models are essential… (more)

Subjects/Keywords: linear prediction; line spectrum pair; minimum-phase property; speech modelling

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bäckström, T. (2004). Linear Predictive Modelling of Speech – Constraints and Line Spectrum Pair Decomposition. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269473/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Bäckström, Tom. “Linear Predictive Modelling of Speech – Constraints and Line Spectrum Pair Decomposition.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269473/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Bäckström, Tom. “Linear Predictive Modelling of Speech – Constraints and Line Spectrum Pair Decomposition.” 2004. Web. 04 Mar 2021.

Vancouver:

Bäckström T. Linear Predictive Modelling of Speech – Constraints and Line Spectrum Pair Decomposition. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269473/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bäckström T. Linear Predictive Modelling of Speech – Constraints and Line Spectrum Pair Decomposition. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269473/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

17. Genty, Goëry. Supercontinuum Generation in Microstructured Fibers and Novel Optical Measurement Techniques.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512270005/

► Over the past few years microstructured fibers have shown potential for many practical applications and permitted significant progress in various domains such as nonlinear optics,… (more)

▼ Over the past few years microstructured fibers have shown potential for many practical applications and permitted significant progress in various domains such as nonlinear optics, medical science or telecommunications as the fabrication process allows for a great flexibility in the design of these fibers. In particular, small core microstructured fibers has proven to be the most efficient way for supercontinuum generation. Supercontinuum is one of the most spectacular outcome of nonlinear optics as it possesses the properties of a laser combined with an ultra-broad bandwidth spanning more than two octaves. The thesis provides a comprehensive review of the different physical mechanisms leading to the generation of these spectra in microstructured fibers. Dispersion, which reflects the dependence of the refractive index of a material on the frequency of light plays a crucial role in the pulse propagation in optical fibers or components. A novel technique to characterize the anomalous dispersion of small core microstructured fibers using short optical pulses is demonstrated. The method presents several advantages over conventional techniques and relies on the spectral modulation resulting from the evolution of the input pulse into a soliton wave. As the demand for capacity of optical networks increases, the requirements for the components employed in transmission systems becomes more stringent. In particular, the dispersion of fiber Bragg gratings or thin-film filters commonly employed in the links needs to be accurately evaluated as it may have a strong impact on the overall performance of the system. A novel method for improving the accuracy of dispersion measurements, based on the well-established phase-shift technique widely used in the characterization of optical components, is presented. The performance of diode lasers can be greatly enhanced with the use of an external cavity configuration. The wavelength tunability of the diode is increased and its linewidth considerably reduced. The behavior of the linewidth of a grating cavity laser is both theoretically and experimentally explored as the oscillation frequency of the laser is varied. Surprisingly, large changes in the linewidth value are observed, which may have an impact in applications requiring lasers with a stable and narrow linewidth. The fabrication of integrated silica-based optical components performing active functionalities is an exciting prospect for obvious reasons. Poling of silica glass is a very promising technique for the development of this type of component as it allows for the introduction of an effective second-order nonlinearity essential for performing active functions. A new technique based on the inscription of Bragg gratings for measuring the second-order nonlinearity induced by negative thermal poling is demonstrated. Advisors/Committee Members: Helsinki University of Technology, Department of Electrical and Communications Engineering, Metrology Research Institute.

Subjects/Keywords: supercontinuum; microstructured fibers; dispersion measurements; linewidth; external cavity laser; poling

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Genty, G. (2004). Supercontinuum Generation in Microstructured Fibers and Novel Optical Measurement Techniques. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512270005/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Genty, Goëry. “Supercontinuum Generation in Microstructured Fibers and Novel Optical Measurement Techniques.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512270005/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Genty, Goëry. “Supercontinuum Generation in Microstructured Fibers and Novel Optical Measurement Techniques.” 2004. Web. 04 Mar 2021.

Vancouver:

Genty G. Supercontinuum Generation in Microstructured Fibers and Novel Optical Measurement Techniques. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270005/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Genty G. Supercontinuum Generation in Microstructured Fibers and Novel Optical Measurement Techniques. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270005/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

18. Esquef, Paulo A. A. Model-Based Analysis of Noisy Musical Recordings with Application to Audio Restoration.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269503/

►

This thesis proposes digital signal processing algorithms for noise reduction and enhancement of audio signals. Approximately half of the work concerns signal modeling techniques for… (more)

Subjects/Keywords: acoustic signal processing; computer music; audio restoration; spectral analysis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Esquef, P. A. A. (2004). Model-Based Analysis of Noisy Musical Recordings with Application to Audio Restoration. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269503/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Esquef, Paulo A A. “Model-Based Analysis of Noisy Musical Recordings with Application to Audio Restoration.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269503/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Esquef, Paulo A A. “Model-Based Analysis of Noisy Musical Recordings with Application to Audio Restoration.” 2004. Web. 04 Mar 2021.

Vancouver:

Esquef PAA. Model-Based Analysis of Noisy Musical Recordings with Application to Audio Restoration. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269503/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Esquef PAA. Model-Based Analysis of Noisy Musical Recordings with Application to Audio Restoration. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269503/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

19. Holopainen, Rauno. Dust in Ventilation Ducts: Accumulation, Measurement and Removal.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269767/

►

This thesis focuses on dust accumulation in, and removal from, recently installed supply air ducts and on the bristle behaviour of rotating duct cleaning brushes.… (more)

▼

This thesis focuses on dust accumulation in, and removal from, recently installed supply air ducts and on the bristle behaviour of rotating duct cleaning brushes. The results of dust accumulation, measured using three different methods, were compared and the amount of dust in newly installed air ducts was evaluated. The vacuum test was found to be an efficient method of collecting dust samples on the duct surface. The vacuum test and the gravimetric tape method gave approximately the same results when the measured dust accumulation on the duct surfaces was 0.1-1.0 g/m2. The gravimetric and optical tape methods can be used to evaluate cleanliness of new ducts when the amount of dust accumulation is 0.1-1.0 g/m2. The effect of protection measures on dust accumulation was studied. The mean amount of accumulated dust after construction was 0.9 g/m2 in cleanliness category P1 ducts, which have special requirements for oil residues and protection measures against contamination during construction, and 2.3 g/m2 in cleanliness category P2 ducts, which have only minor protection requirements and are for normal use. The results show that dust accumulation in category P1 ducts was significantly lower (P < 0.008) than in category P2 ducts. The highest mean amount of dust accumulation was found in the middle of the ducts and the lowest amount near the air handling units. The efficiency of two dry air duct cleaning methods applied to new air ducts was compared. Mechanical brushing and compressed air cleaning methods were found to be efficient in removing dust from the newly installed air duct surfaces. Mechanical brushing was more efficient in metal ducts, while the compressed air cleaning method was more efficient in plastic ducts. The mean amount of residual dust on the duct surfaces was below 0.4 g/m2 after duct cleaning. However, neither of the cleaning methods studied was efficient enough to clean ducts that had a high level of residual oil (216-338 mg/m2) on the duct surfaces. A mathematical model to simulate the behaviour of a single bristle of a rotating duct cleaning brush was developed. The results of the simulation were compared with those obtained from a laboratory test. The simulated and experimental results were found to be in reasonable agreement. The dependence of the normal force and the contact angle as a function of various parameters was studied. The simulation and experimental results showed that the normal force and contact angle increase as a function of the rotation speed. Further, the thickness of the bristle was found to have a strong effect on the normal force. Air drag has only a slight effect on the deflection of the bristle. The model can be used as a first step in the systematic design of brushes. However, further theoretical and experimental research is needed to determine the dependency, for instance, between the brush tip normal force and its cleaning efficiency.

Report / Helsinki University of Technology, Laboratory of Heating, Ventilating and Air Conditioning. A, ISSN 1238-8971; 9

Advisors/Committee Members: Helsinki University of Technology, Department of Mechanical Engineering, Laboratory of Heating, Ventilating and Air Conditioning.

Subjects/Keywords: duct; dust; cleanliness categories; duct cleaning; bristle model; normal force; contact angle; air drag

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Holopainen, R. (2004). Dust in Ventilation Ducts: Accumulation, Measurement and Removal. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269767/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Holopainen, Rauno. “Dust in Ventilation Ducts: Accumulation, Measurement and Removal.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269767/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Holopainen, Rauno. “Dust in Ventilation Ducts: Accumulation, Measurement and Removal.” 2004. Web. 04 Mar 2021.

Vancouver:

Holopainen R. Dust in Ventilation Ducts: Accumulation, Measurement and Removal. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269767/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Holopainen R. Dust in Ventilation Ducts: Accumulation, Measurement and Removal. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269767/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

20. Uusitupa, Tero. Studying Electromagnetic Wave-Guiding and Resonating Devices.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269805/

►

Various electromagnetic wave-guiding and resonating structures are studied. The structures in question are rather complicated and thus, significant part of the used analysis methods are… (more)

▼

Various electromagnetic wave-guiding and resonating structures are studied. The structures in question are rather complicated and thus, significant part of the used analysis methods are numerical. Numerical field computation is based on finite-difference method (FD) or on finite-difference time-domain method (FDTD). When possible, analytical methods have been used, often in conjunction with numerical computation. Most of the structures, if not all, find real-life applications. Thus, the focus has been much on such issues as fluency of structure design and quickness of analysis. Firstly, combline-filter structures are investigated. These components are widely used in mobile communication devices, in radio-frequency and microwave regime, for example. A semianalytic analysis method, which is based on multiconductor-transmission-line theory and 2-D numerical field computation via FD method, is found very efficient. Computationally costly 3-D numerical field computation is avoided. This speeds up the design process of combline filters. Secondly, so-called hard-surface-waveguide components are analytically studied. When approximating the longitudinally corrugated waveguide wall with an ideal hard surface, one can concentrate on the effects caused by the media inside the tube. First waveguide component is filled with uniaxial anisotropic medium. For this structure, which can be used as a polarisation transformer, analytical solutions are found for transmitted and reflected field, and especially for the helicity of the transmitted field. Second waveguide component is filled with gyrotropic medium, which is electrically controllable ferrite in this case. This component can be used as a mode transformer, for example, from TM to TE mode. Analytical solutions are found for reflected and transmitted fields. Finally, wave-guiding structures based on photonic-bandgap (PBG) material are studied. This kind of periodically inhomogeneous material is also known as photonic crystal (PhC), having the ability to inhibit the propagation of electromagnetic wave inside the crystal. Carefully designed PBG components may find several applications, for example, in the integrated optics. In this thesis, the focus has been on PBG material based on triangular lattice of air holes etched through dielectric background. Further, waveguide bends have been of special interest, partly because they give a chance of realising tight light-channel bends for integrated optics. Various issues related to FDTD analysis and design of PBG structures are discussed. The importance of PBG-component optimisation is demonstrated. Promising results are obtained for extremely tight bends, although radiation losses in real 3-D structures are recognized as a problem. Some basic components, 60 and 120 degree waveguide bends, and a taper, have been designed.

Electromagnetics Laboratory report series, ISSN 1456-632X; 426

Advisors/Committee Members: Helsinki University of Technology, Department of Electrical and Communications Engineering, Electromagnetics Laboratory.

Subjects/Keywords: waveguide; combline filter; photonic bandgap; photonic crystal; hard surface; finite-difference method; FDTD

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Uusitupa, T. (2004). Studying Electromagnetic Wave-Guiding and Resonating Devices. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269805/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Uusitupa, Tero. “Studying Electromagnetic Wave-Guiding and Resonating Devices.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269805/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Uusitupa, Tero. “Studying Electromagnetic Wave-Guiding and Resonating Devices.” 2004. Web. 04 Mar 2021.

Vancouver:

Uusitupa T. Studying Electromagnetic Wave-Guiding and Resonating Devices. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269805/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Uusitupa T. Studying Electromagnetic Wave-Guiding and Resonating Devices. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269805/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

21. Salin, Timo. Quenching and Blowup Problems for Reaction Diffusion Equations.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269872/

►

In this thesis we study quenching and blowup problems for reaction diffusion equations with Cauchy-Dirichlet data. We give sufficient conditions for certain reaction terms under… (more)

Subjects/Keywords: reaction-diffusion equation; quenching; quenching set; quenching rate; asymptotic behavior of solutions; refined asymptotics; blow-up; blow-up set; blow-up rate

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Salin, T. (2004). Quenching and Blowup Problems for Reaction Diffusion Equations. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269872/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Salin, Timo. “Quenching and Blowup Problems for Reaction Diffusion Equations.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269872/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Salin, Timo. “Quenching and Blowup Problems for Reaction Diffusion Equations.” 2004. Web. 04 Mar 2021.

Vancouver:

Salin T. Quenching and Blowup Problems for Reaction Diffusion Equations. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269872/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Salin T. Quenching and Blowup Problems for Reaction Diffusion Equations. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269872/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

22. Hirvisalo, Vesa. Using Static Program Analysis to Compile Fast Cache Simulators.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512270137/

►

This thesis presents a generic approach towards compiling fast execution-driven simulators, and applies this to cache simulation of programs. The resulting cache simulation method reduces… (more)

▼

This thesis presents a generic approach towards compiling fast execution-driven simulators, and applies this to cache simulation of programs. The resulting cache simulation method reduces the time needed for cache performance evaluations without losing the accuracy of the results. Fast cache simulators are needed in the performance analysis of software systems. To properly understand the cache behavior caused by a program, simulations must be performed with a sufficient number of inputs. Traditional simulation of memory operations of a program can be orders of magnitude slower than the execution of the program. This leads to simulation times that are often infeasible in software development. The approach of this thesis is based on using static cache analysis to guide partial evaluation and slicing of simulators. Because of redundancy in memory access patterns of typical programs, an execution-driven cache simulator program can be partially evaluated during its compilation. Program slicing can be used to remove the computations that have no effect on the simulation result. The static cache analysis presented in this thesis is generic. The analysis is designed especially for programs that use dynamic addressing. The thesis assumes an address analysis that gives the cache analysis static information about cache aliases and cache conflicts between accessed memory lines. To determine the memory references that always cause cache hits or cache misses, the thesis describes both must and may analyses of cache states. The cache state analysis is built by using abstract interpretation. Based on the use of abstract interpretation, the soundness of the analysis is proved. The potential performance of the method was experimentally evaluated. The thesis describes both a tool set implementing the cache analysis method and experiments done with the tool set. The experiments indicate that a simple implementation is capable of significantly speeding up the simulations.

Helsinki University of Technology, Department of Computer Science and Engineering, Laboratory of Information Processing Science, ISSN 1239-6885; 41

Advisors/Committee Members: Helsinki University of Technology, Department of Computer Science and Engineering, Laboratory of Information Processing Science.

Subjects/Keywords: static analysis; program analysis; performance analysis; cache simulation; program slicing

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Hirvisalo, V. (2004). Using Static Program Analysis to Compile Fast Cache Simulators. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512270137/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hirvisalo, Vesa. “Using Static Program Analysis to Compile Fast Cache Simulators.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512270137/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hirvisalo, Vesa. “Using Static Program Analysis to Compile Fast Cache Simulators.” 2004. Web. 04 Mar 2021.

Vancouver:

Hirvisalo V. Using Static Program Analysis to Compile Fast Cache Simulators. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270137/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hirvisalo V. Using Static Program Analysis to Compile Fast Cache Simulators. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270137/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

23. Salminen, Justin. Chemical Thermodynamics of Aqueous Electrolyte Systems for Industrial and Environmental Applications.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269368/

► This thesis consists of studies of chemical thermodynamics of aqueous electrolytes for industrial and environmental applications. Calculations have been used to represent vapor-liquid-solid equilibria and… (more)

Subjects/Keywords: Gibbs energy; modelling; aqueous; electrolyte; process

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Salminen, J. (2004). Chemical Thermodynamics of Aqueous Electrolyte Systems for Industrial and Environmental Applications. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269368/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Salminen, Justin. “Chemical Thermodynamics of Aqueous Electrolyte Systems for Industrial and Environmental Applications.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269368/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Salminen, Justin. “Chemical Thermodynamics of Aqueous Electrolyte Systems for Industrial and Environmental Applications.” 2004. Web. 04 Mar 2021.

Vancouver:

Salminen J. Chemical Thermodynamics of Aqueous Electrolyte Systems for Industrial and Environmental Applications. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269368/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Salminen J. Chemical Thermodynamics of Aqueous Electrolyte Systems for Industrial and Environmental Applications. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269368/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

24. Noponen, Matti. Current Distribution Measurements and Modeling of Mass Transfer in Polymer Electrolyte Fuel Cells.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269783/

►

The polymer electrolyte fuel cell (PEFC) is considered as an attractive option to produce electric power in many applications ranging from a few watt portable… (more)

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The polymer electrolyte fuel cell (PEFC) is considered as an attractive option to produce electric power in many applications ranging from a few watt portable up to several kilowatt automotive applications. The advantage of the PEFC in these applications stems from its high efficiency, low emissions, silent operation and possible low production costs in the future. However, the main factor hindering the market penetration of PEFC applications is the present high production cost of the cell. To allow lower costs for the PEFC, the cell area has to be used efficiently in order to minimize the material usage. This requires the maximization of the cell performance by enhancing the current production at low potential losses. At high current densities, mass transfer losses become the dominating loss mechanism. The mass transfer losses usually produce uneven current production throughout the active area of the cell. The local current production can be studied by experimental and computational methods. For the experimental characterization of the local current production, two different measurement system based on segmented current collectors have been constructed. The other is for a small PEFC operating with natural convection and the other is for a large PEFC operating with forced convection. In addition to the experimental methods, two different theoretical PEFC models have been developed, the other for the free-breathing PEFC and the other for the forced convection PEFC. The current distribution studies were conducted for the free-breathing PEFC in order to determine the feasibility of using natural convection as an air supply method for the cathode reaction at different cell temperatures and ambient conditions. It was observed that the cell performance is highly dependent on the operating conditions and that the current distribution is uneven in the most cases. The current distribution measurements conducted with the large PEFC were used mainly for the model validation purposes. It was shown that under certain operating conditions the current distribution was uniform and thus a one-dimensional PEFC model could be used. The results showed that two-phase and non-isothermal conditions are likely to exist when a PEFC is operated at high current densities and with well humidified gases.

Helsinki University of Technology publications in engineering physics. A, ISSN 1456-3320; 828

Advisors/Committee Members: Helsinki University of Technology, Department of Engineering Physics and Mathematics, Advanced Energy Systems.

Subjects/Keywords: fuel cell; PEFC; PEMFC; segmented cell; current distribution; mass transfer; two-phase; water management; thermal management; natural convection; forced convection; modeling

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Noponen, M. (2004). Current Distribution Measurements and Modeling of Mass Transfer in Polymer Electrolyte Fuel Cells. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269783/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Noponen, Matti. “Current Distribution Measurements and Modeling of Mass Transfer in Polymer Electrolyte Fuel Cells.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269783/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Noponen, Matti. “Current Distribution Measurements and Modeling of Mass Transfer in Polymer Electrolyte Fuel Cells.” 2004. Web. 04 Mar 2021.

Vancouver:

Noponen M. Current Distribution Measurements and Modeling of Mass Transfer in Polymer Electrolyte Fuel Cells. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269783/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Noponen M. Current Distribution Measurements and Modeling of Mass Transfer in Polymer Electrolyte Fuel Cells. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269783/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

25. Mennola, Tuomas. Mass Transport in Polymer Electrolyte Membrane Fuel Cells Using Natural Convection for Air Supply.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269848/

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A fuel cell converts chemical energy into electricity and heat through electrochemical reactions. Polymer electrolyte membrane fuel cells (PEMFCs) are approaching commercialization in many applications,… (more)

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A fuel cell converts chemical energy into electricity and heat through electrochemical reactions. Polymer electrolyte membrane fuel cells (PEMFCs) are approaching commercialization in many applications, including transportation, stationary power, and portable devices. In this thesis, the focus was on small-scale PEMFCs, in which natural convection is used as the air supply method. A cell design with straight vertical cathode channels was studied using experimental and modeling methods, in order to obtain a quantitative insight into mass transport phenomena and to identify the performance limiting processes. The variation of mass transport conditions over the active area of the cell was studied using a current distribution measurement system, which was based on the use of a segmented current collector. The accuracy of the method was analyzed by experimental work and numerical simulation. In order to quantify the local mole fractions of water and oxygen, and the velocity of buoyancy-driven air flow in the cathode channel, a numerical model was developed to describe mass transport in the cathode channel and the gas diffusion layer. Water transport across the polymer membrane was studied by measuring the fraction of product water exiting through the anode. The results give indication of the variation of net water transport coefficient across the active area. The redistribution of water along with the hydrogen flow was also observed. The effect of ambient temperature and relative humidity on cell performance was investigated in a climate chamber. For stack research, a measurement approach was developed for determining the ohmic voltage losses of individual cells in a stack by the current interruption method. As an overall conclusion, it was found that the cell design should be improved especially from the point of view of water management. In order to reduce flooding problems, the cross-section and length of the cathode channels were identified as key parameters to be optimized. It was also found that mechanically rigid gas diffusion layer materials are advantageous for designing an optimized geometry. In addition, it was found that the choice of the anode flow geometry can be used to control the distribution of water across the active area.

Helsinki University of Technology publications in engineering physics. A, ISSN 1456-3320; 827

Advisors/Committee Members: Helsinki University of Technology, Department of Engineering Physics and Mathematics, Advanced Energy Systems.

Subjects/Keywords: PEMFC; cathode; natural convection; water management; mass transport; current distribution; modeling; current interruption; stack

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Mennola, T. (2004). Mass Transport in Polymer Electrolyte Membrane Fuel Cells Using Natural Convection for Air Supply. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269848/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Mennola, Tuomas. “Mass Transport in Polymer Electrolyte Membrane Fuel Cells Using Natural Convection for Air Supply.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269848/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Mennola, Tuomas. “Mass Transport in Polymer Electrolyte Membrane Fuel Cells Using Natural Convection for Air Supply.” 2004. Web. 04 Mar 2021.

Vancouver:

Mennola T. Mass Transport in Polymer Electrolyte Membrane Fuel Cells Using Natural Convection for Air Supply. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269848/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Mennola T. Mass Transport in Polymer Electrolyte Membrane Fuel Cells Using Natural Convection for Air Supply. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269848/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

26. Harmaakorpi, Vesa. Building a Competitive Regional Innovation Environment – the Regional Development Platform Method as a Tool for Regional Innovation Policy.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512270110/

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The study focuses on building a regional innovation policy tool that takes into account the demands of the present techno-economic and socio-institutional paradigms. Regions are… (more)

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The study focuses on building a regional innovation policy tool that takes into account the demands of the present techno-economic and socio-institutional paradigms. Regions are seen to be strongly dependent on their history. The competitiveness of a region is based on the regional resource configurations. In a turbulent world these resource configurations have to be renewed over time setting demands for regional dynamic capabilities. This study emphasises five regional dynamic capabilities: leadership capability, visionary capability, learning capability, networking capability and innovative capability. The study takes a holistic point of view in assessing the regional innovation environment. This environment is seen as a system of innovation networks and institutions located within a region, with regular and strong internal interaction that promotes innovativeness and is characterised by embeddedness. Innovations are increasingly seen to be the results of non-linear processes deeply embedded in normal social and economic activities. The non-linear and interactive nature of the innovation processes sets new demands for social cohesion in the regional innovation system. The new era is crying out for innovation policy tools that foster the visionary, leadership, networking and learning activities in the process of designing and implementing innovation policies and strategies. In this study a new tool for regional innovation policy – the Regional Development Platform Method – is designed and tested. The main aspects behind the creation of this innovation policy tool are: (i) understanding the effects of the changing techno-economic-paradigm on the regional innovation environment (ii) understanding the phenomena of regional path-dependency and agglomeration, (iii) avoiding regional lock-ins, (iv) defining competitive regional resource configurations, (v) creating multi-actor innovation networks to exploit the resource configurations, (vi) enhancing the absorptive capacity of the innovation networks, (vii) creating sufficiently creative social capital, (viii) promoting regional dynamic capabilities and (ix) understanding the multi-level governance environment in forming innovation policies and strategies. The Regional Development Platform Method is tested in the Lahti region in Finland. The experiences of the policy tool have been encouraging and it has crucially influenced the most recent strategies and programmes in the region.

Doctoral dissertations series / Helsinki University of Technology, Lahti Center, ISSN 1459-9988; 2004/1:b

Advisors/Committee Members: Helsinki University of Technology, Department of Industrial Engineering and Management, HUT Lahti Center.

Subjects/Keywords: regional innovation systems; innovation policies; regional competitiveness; learning systems; networking; social capital; network leadership

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Harmaakorpi, V. (2004). Building a Competitive Regional Innovation Environment – the Regional Development Platform Method as a Tool for Regional Innovation Policy. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512270110/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Harmaakorpi, Vesa. “Building a Competitive Regional Innovation Environment – the Regional Development Platform Method as a Tool for Regional Innovation Policy.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512270110/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Harmaakorpi, Vesa. “Building a Competitive Regional Innovation Environment – the Regional Development Platform Method as a Tool for Regional Innovation Policy.” 2004. Web. 04 Mar 2021.

Vancouver:

Harmaakorpi V. Building a Competitive Regional Innovation Environment – the Regional Development Platform Method as a Tool for Regional Innovation Policy. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270110/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Harmaakorpi V. Building a Competitive Regional Innovation Environment – the Regional Development Platform Method as a Tool for Regional Innovation Policy. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270110/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

27. Konttinen, Petri. Characterization and Aging Studies of Selective Solar C/Al2O3/Al Absorber Surfaces.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn951227003X/

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Solar thermal collectors are mainly used for domestic water and space heating. They capture incident solar radiation, convert it to usable thermal energy, and transfer… (more)

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Solar thermal collectors are mainly used for domestic water and space heating. They capture incident solar radiation, convert it to usable thermal energy, and transfer the energy into a heat transfer fluid. All of this should be accomplished economically with minimal energy loss. One of the most important components of the solar thermal collector is the solar absorber. To be effective, the absorber should exhibit wavelength selectivity, i.e. have maximum solar absorptance and minimum thermal emittance. Selective solar absorbers have been studied intensively since the 1950's. State-of-the-art sputtered selective solar absorbers have good optical properties and long lifetime. A drawback can be high manufacturing costs. The main purpose of this thesis was the characterization and improvement of a mechanically-manufactured selective C/Al2O3/Al absorber surface. The manufacturing method is the only one based on solely mechanical treatment. The optical properties and microstructure of surface samples were analysed. Together with an industrial partner the manufacturing methods were refined. Comprehensive accelerated aging studies were carried out for the absorber surface. As a result the solar absorptance and the thermal emittance were improved to 0.90 and 0.22, respectively. The microstructure of the surface is composed of microgrooves and unhomogeneous carbon, graphite or graphite/alumina clusters. Inside a glazed collector a service lifetime between 20 and 25 years can be expected. The main degradation mechanism found was hydration of Al2O3 if condensed water is present on the surface at an elevated temperature. For very humid climates, an additional moisture barrier would be advisable even for glazed collector applications. For non-glazed applications moisture resistance needs to be improved. The price of the required manufacturing infrastructure for the C/Al2O3/Al absorber varies. It may be very low for manual manufacturing up to some tens of thousands euros for a more sophisticated mechanical workshop. Optical properties and energy yield of the C/Al2O3/Al absorber are in the same range as the best commercial spectrally selective paints, but lower than sputtered surfaces. Economically the C/Al2O3/Al absorber may compete with selective and non-selective paints in most glazed applications.

Helsinki University of Technology publications in engineering physics. A, ISSN 1459-7268; 826

Advisors/Committee Members: Helsinki University of Technology, Department of Engineering Physics and Mathematics, Advanced Energy Systems.

Subjects/Keywords: solar energy; solar thermal absorber; accelerated aging; mechanical manufacturing

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Konttinen, P. (2004). Characterization and Aging Studies of Selective Solar C/Al2O3/Al Absorber Surfaces. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn951227003X/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Konttinen, Petri. “Characterization and Aging Studies of Selective Solar C/Al2O3/Al Absorber Surfaces.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn951227003X/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Konttinen, Petri. “Characterization and Aging Studies of Selective Solar C/Al2O3/Al Absorber Surfaces.” 2004. Web. 04 Mar 2021.

Vancouver:

Konttinen P. Characterization and Aging Studies of Selective Solar C/Al2O3/Al Absorber Surfaces. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn951227003X/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Konttinen P. Characterization and Aging Studies of Selective Solar C/Al2O3/Al Absorber Surfaces. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn951227003X/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

28. Ahllund, Olli. Maanomistajan asema ja vaikutusmahdollisuudet tilusjärjestelyissä, erityisesti Pedersöressä isojaosta nykypäivään.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512270064/

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The aim of this study was to investigate the position of the landowner and his/her degree of influence on land consolidation in general and specially… (more)

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The aim of this study was to investigate the position of the landowner and his/her degree of influence on land consolidation in general and specially within the municipality of Pedersöre. This study is divided into two fields: a) the decision-making and the degree of influence of a private landowner and b) the general development of land consolidation. This study emphasizes the real possibilities the landowner has of influencing land consolidation and how these possibilities appear in practise. The continuity of Finnish land consolidation activity is also investigated. The aim was to find out if the land reform process has been a slow and long lasting or if the cadastral procedures have been separate technical procedures. The empiric data for this study was collected from land consolidation records and articles published in a local newspaper from Pedersöre during the 20th century. The method used in this study was a qualitative content analysis. Financial measures taken by the state in land consolidation procedures has, according to this study stimulated the implementation of land consolidation procedures. But this alone has not been sufficient to start the land consolidation process. Opinion leaders among the landowners and the economic results of the procedures have been central internal factors. These have also influenced the implementation of land consolidation procedures. The long duration of land consolidation procedures has made it significantly difficult for a landowner to estimate the economic outcome of land consolidation. This study suggests that there has been a long lasting and almost continuous land reform within the research area (Pedersöre). Its main purpose has been to correct the defects of early land consolidation and to lower the costs of production on the farms by improving draining, access roads and the division of land.

Kiinteistöopin ja talousoikeuden julkaisuja / Teknillinen korkeakoulu, maanmittaustekniikan laitos, kiinteistöoppi. A, ISSN 0785-5079; 36

Advisors/Committee Members: Helsinki University of Technology, Department of Surveying, Institute of Real Estate Studies.

Subjects/Keywords: land consolidation; position of a landowner; possibilities of influencing; tilusjärjestely; maanomistajan asema; vaikutusmahdollisuudet

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ahllund, O. (2004). Maanomistajan asema ja vaikutusmahdollisuudet tilusjärjestelyissä, erityisesti Pedersöressä isojaosta nykypäivään. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512270064/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ahllund, Olli. “Maanomistajan asema ja vaikutusmahdollisuudet tilusjärjestelyissä, erityisesti Pedersöressä isojaosta nykypäivään.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512270064/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ahllund, Olli. “Maanomistajan asema ja vaikutusmahdollisuudet tilusjärjestelyissä, erityisesti Pedersöressä isojaosta nykypäivään.” 2004. Web. 04 Mar 2021.

Vancouver:

Ahllund O. Maanomistajan asema ja vaikutusmahdollisuudet tilusjärjestelyissä, erityisesti Pedersöressä isojaosta nykypäivään. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270064/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ahllund O. Maanomistajan asema ja vaikutusmahdollisuudet tilusjärjestelyissä, erityisesti Pedersöressä isojaosta nykypäivään. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270064/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

29. Kiiskinen, Ari. Looking for Physics Beyond the Standard Model: Searches for Charged Higgs Bosons at e+e− Colliders.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9521016809/

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This thesis describes direct searches for pair production of charged Higgs bosons performed in the data collected by the DELPHI detector at the LEP collider… (more)

Subjects/Keywords: charged Higgs bosons; two Higgs doublet models; Higgs boson searches; LEP; DELPHI; linear colliders

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kiiskinen, A. (2004). Looking for Physics Beyond the Standard Model: Searches for Charged Higgs Bosons at e+e− Colliders. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9521016809/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kiiskinen, Ari. “Looking for Physics Beyond the Standard Model: Searches for Charged Higgs Bosons at e+e− Colliders.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9521016809/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kiiskinen, Ari. “Looking for Physics Beyond the Standard Model: Searches for Charged Higgs Bosons at e+e− Colliders.” 2004. Web. 04 Mar 2021.

Vancouver:

Kiiskinen A. Looking for Physics Beyond the Standard Model: Searches for Charged Higgs Bosons at e+e− Colliders. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9521016809/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kiiskinen A. Looking for Physics Beyond the Standard Model: Searches for Charged Higgs Bosons at e+e− Colliders. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9521016809/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

30. Ranki-Kilpinen, Tiina. Sulphation of Cuprous and Cupric Oxide Dusts and Heterogeneous Copper Matte Particles in Simulated Flash Smelting Heat Recovery Boiler Conditions.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512270226/

► Copper smelting with the Outokumpu flash smelting process generates significant amounts of SO2-rich off-gas and flue dust. From the smelting unit, gases with a dust… (more)

▼ Copper smelting with the Outokumpu flash smelting process generates significant amounts of SO2-rich off-gas and flue dust. From the smelting unit, gases with a dust load are directed into a heat recovery boiler (also known as a waste heat boiler). In the radiation section temperature decreases, sulphates become thermodynamically stable, and the sulphation of oxidic dust particles commences. Releasing heat may lead to an increase in particle temperatures, softening of the sulphated particles, and the formation of dust accretions on the heat transfer surfaces. Decreased heat transfer efficiency and blockages of the gas flow paths may cause severe operational problems. To maintain stable boiler operation, sulphation behaviour has to be well understood, but only scant published data concerning dust sulphation reactions is available. The objective of this work was to gain basic knowledge of the sulphation behaviour of dust components to ascertain that boiler design and operation can be carried out so that sulphate formation takes place in a controlled manner. The reactions of synthetic Cu2O and CuO (mainly 37-53 µm) and a partially oxidised copper matte were studied experimentally with the aim of arriving at a better understanding of dust sulphation in industrial heat recovery boilers. The parameters in the laboratory-scale experiments were gas composition (20-60 vol-% SO2, 2.5-10 vol-% O2), temperature (560-660 °C), reaction time, and particle size. Standard chemical analysis and scanning electron microscopy with EDS were utilised when examining the samples. Sulphate formation was found to be sensitive to gas composition and temperature. Also particle size and surface morphology have significant effects on the sulphation rate. On the basis of the experimental results the temperature range for effective sulphation of pure cuprous oxide is narrow; the optimal sulphate formation temperature lies between 580-640 °C, depending on the gas composition. An increase in oxygen concentration expands the favourable temperature range and lowers the most optimal sulphate formation temperature; on the contrary an increase in sulphur dioxide concentration raises the favourable sulphation temperature. On the basis of the present experiments pure cupric oxide behaves like cuprous oxide, but the conversion degrees are slightly lower and there is not such a clear enhance in the sulphation rate at a certain temperature. Fine, heterogeneous partially oxidised matte reacts significantly faster compared to synthetic oxides. The reason for more effective sulphation is suggested to be the smaller particle size and more detailed morphology (larger specific surface area). In the heat recovery boiler dust particles must have a sufficient residence time in the gas phase at a correct temperature range to allow the dust particles to reach complete conversion in the radiation section before they enter the boiler convection section and come into contact with the convection tube banks. Enough oxygen has to be supplied to the appropriate zone to… Advisors/Committee Members: Helsinki University of Technology, Department of Materials Science and Rock Engineering, Laboratory of Materials Processing and Powder Metallurgy.

Subjects/Keywords: sulphation; cuprous oxide; cupric oxide; flue dust; flash smelting; heat recovery boiler

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ranki-Kilpinen, T. (2004). Sulphation of Cuprous and Cupric Oxide Dusts and Heterogeneous Copper Matte Particles in Simulated Flash Smelting Heat Recovery Boiler Conditions. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512270226/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ranki-Kilpinen, Tiina. “Sulphation of Cuprous and Cupric Oxide Dusts and Heterogeneous Copper Matte Particles in Simulated Flash Smelting Heat Recovery Boiler Conditions.” 2004. Thesis, Helsinki University of Technology. Accessed March 04, 2021. http://lib.tkk.fi/Diss/2004/isbn9512270226/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ranki-Kilpinen, Tiina. “Sulphation of Cuprous and Cupric Oxide Dusts and Heterogeneous Copper Matte Particles in Simulated Flash Smelting Heat Recovery Boiler Conditions.” 2004. Web. 04 Mar 2021.

Vancouver:

Ranki-Kilpinen T. Sulphation of Cuprous and Cupric Oxide Dusts and Heterogeneous Copper Matte Particles in Simulated Flash Smelting Heat Recovery Boiler Conditions. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Mar 04]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270226/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ranki-Kilpinen T. Sulphation of Cuprous and Cupric Oxide Dusts and Heterogeneous Copper Matte Particles in Simulated Flash Smelting Heat Recovery Boiler Conditions. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512270226/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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Open Access Theses and Dissertations