subject:(Post compression)

Delft University of Technology

1. Dykstra, D.M.J. (author). Modelling Delaminations in Composite Panels: Including Novel Theories for Post-Buckling and Delamination Growth.

Degree: 2016, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:21486e29-e491-4e0b-b170-a30af9a24f7b

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Even though composite materials are being applied more and more often, these materials are often not used to their full potential. In particular, composite materials… (more)

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Even though composite materials are being applied more and more often, these materials are often not used to their full potential. In particular, composite materials are very sensitive to Compression-After-Impact (CAI), typically leading to knockdown factors in the order of 0.65. Many researchers have tried to predict the effects of Compression-After-Impact, either using finite element or analytical methods. While non-linear finite element methods can capture most of the damage mechanisms accurately, large computational power is required rendering such methods unpractical for optimisations. On the other hand, many analytical methods are limited in accuracy, especially at higher impact energies, which are often critical for design. In particular, no analytical model has ever been developed which can capture the progressive post-buckling behaviour of a panel with elliptical delaminations, let alone in a variable stiffness laminate. In order to solve this problem, a novel general theory for post-buckling was proposed. With this theory, the non-linear effects of post-buckling phenomena can be captured using a quasi-linear system of equations. This theory was used, in combination with the Rayleigh-Ritz method, to model the progressive post-buckling behaviour of variable stiffness composite laminates with single and multiple delaminations under compression. In general, very good agreement was found in comparison with non-linear finite element methods. A novel theory was also proposed to predict growth of post-buckling elliptical delaminations by analysing the delaminating resin layer as elastic foundation. The methods developed in this thesis shows promising results for applications in models which determine the compressive strength of composite panels after impact or the compressive strength of composite panels with delaminations in general. In particular, models using these theories will be able to capture the combined effect of various damage phenomena for panels with larger delaminations, which is typically a limitation of existing models. Moreover, the developed theory for post-buckling is not only applicable to the Rayleigh-Ritz method but can be used for general post-buckling calculations of panels and beams. In particular, this theory could also be interesting for finite element calculations.

Aerospace Engineering

Aerospace Structures & Materials

Aerospace Structures & Computational Mechanics

Advisors/Committee Members: Kassapoglou, C. (mentor), Esrail, F. (mentor).

Subjects/Keywords: buckling; post-buckling; composites; composite panels; compression; delamination growth; impact

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

APA (6^th Edition):

Dykstra, D. M. J. (. (2016). Modelling Delaminations in Composite Panels: Including Novel Theories for Post-Buckling and Delamination Growth. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:21486e29-e491-4e0b-b170-a30af9a24f7b

Chicago Manual of Style (16^th Edition):

Dykstra, D M J (author). “Modelling Delaminations in Composite Panels: Including Novel Theories for Post-Buckling and Delamination Growth.” 2016. Masters Thesis, Delft University of Technology. Accessed April 11, 2021. http://resolver.tudelft.nl/uuid:21486e29-e491-4e0b-b170-a30af9a24f7b.

MLA Handbook (7^th Edition):

Dykstra, D M J (author). “Modelling Delaminations in Composite Panels: Including Novel Theories for Post-Buckling and Delamination Growth.” 2016. Web. 11 Apr 2021.

Vancouver:

Dykstra DMJ(. Modelling Delaminations in Composite Panels: Including Novel Theories for Post-Buckling and Delamination Growth. [Internet] [Masters thesis]. Delft University of Technology; 2016. [cited 2021 Apr 11]. Available from: http://resolver.tudelft.nl/uuid:21486e29-e491-4e0b-b170-a30af9a24f7b.

Council of Science Editors:

Dykstra DMJ(. Modelling Delaminations in Composite Panels: Including Novel Theories for Post-Buckling and Delamination Growth. [Masters Thesis]. Delft University of Technology; 2016. Available from: http://resolver.tudelft.nl/uuid:21486e29-e491-4e0b-b170-a30af9a24f7b

Johannes Gutenberg Universität Mainz

2. Friese, Conrad Friedrich. Analyse zur Auswirkung der irreversiblen Wavelet-Kompression (JPEG2000) auf CT-Bildverarbeitungs- und Darstellungsalgorithmen.

Degree: 2014, Johannes Gutenberg Universität Mainz

URL: http://ubm.opus.hbz-nrw.de/volltexte/2014/3791/

► Der technische Fortschritt konfrontiert die medizinische Bildgebung wie keine andere Sparte der Medizin mit einem rasanten Anstieg zu speichernder Daten. Anschaffung, Wartung und Ausbau der… (more)

▼ Der technische Fortschritt konfrontiert die medizinische Bildgebung wie keine andere Sparte der Medizin mit einem rasanten Anstieg zu speichernder Daten. Anschaffung, Wartung und Ausbau der nötigen Infrastruktur entwickeln sich zunehmend zu einem ökonomischen Faktor. Ein Verfahren, welches diesem Trend etwas entgegensetzten könnte ist die irreversible Bilddatenkompression. Sie ist seit über 10 Jahren Gegenstand vieler Studien, deren Ergebnisse sich wiederum in Empfehlungen zum Einsatz irreversibler Kompression mehrerer nationaler und internationaler Organisation, wie CAR, DRG, RCR und ESR wiederspiegeln. Tenor dieser Empfehlungen ist, dass der Einsatz von moderater irreversibler Bilddatenkompression sicher und sinnvoll ist. Teil dieser Empfehlungen sind auch Angaben über das Maß an Kompression, ausgedrückt in Kompressionsraten, welche je nach Untersuchung und anatomischer Region als sicher anwendbar gelten und keinen diagnostisch relevanten Verlust der komprimierten Bilder erzeugen.rnVerschiedene Kompressionsalgorithmen wurden vorgeschlagen. Letztendlich haben sich vor allem die beiden weit verbreiteten Algorithmen JPEG und JPEG2000 bewährt. Letzterer erfährt in letzter Zeit zunehmen Anwendung, aufgrund seiner einfacheren Handhabung und seiner umfangreichen Zusatzfunktionen.rnAufgrund rechtlich-ethischer Bedenken hat die irreversible Kompression keine breite praktische Anwendung finden können. Dafür verantwortlich ist unter anderem auch die Unklarheit, wie sich irreversible Kompression auf Nach- und Weiterverarbeitung (sog. Postprocessing) medizinischer Bilder, wie Segmentierung, Volumetrie oder 3D-Darstellung, auswirkt. Bisherige Studien zu diesem Thema umfassen vier verschiedene Postprocessing-Algorithmen. Die untersuchten Algorithmen zeigten sich bei verlustbehafteter Kompression im Bereich der erwähnten, publizierten Kompressionsraten weitgehend unbeeinflusst. Lediglich die computergestützte Messung von Stenosegraden in der digitalen Koronarangiographie kollidiert mit den in Großbritannien geltenden Empfehlungen. Die Verwendung unterschiedlicher Kompressionsalgorithmen schränkt die allgemeinernAussagekraft dieser Studienergebnisse außerdem ein.rnZur Erweiterung der Studienlage wurden vier weitere Nach- und Weiterverarbeitungsalgorithmen auf ihre Kompressionstoleranz untersucht. Dabei wurden die Kompressionsraten von 8:1, 10:1 und 15:1 verwendet, welche um die empfohlenen Kompressionsraten von CAR, DRG, RCR und ESR liegen und so ein praxisnahes Setting bieten. Als Kompressionsalgorithmus wurde JPEG2000 verwendet, aufgrund seiner zunehmenden Nutzung in Studien sowie seiner bereits erwähnten Vorzüge in Sachen Handhabung und Zusatzfunktionen. Die vier Algorithmen umfassten das 3D-Volume rendering von CT-Angiographien der Becken-Bein-Gefäße, die Computer-assistierte Detektion von Lungenrundherden, die automatisierte Volumetrie von Leberrundherden und die funktionelle Bestimmung der Ejektionsfraktion in computertomographischen Aufnahmen des Herzens.rnAlle vier Algorithmen zeigten keinen Einfluss durch irreversibler…

Subjects/Keywords: irreversible Bilddatenkompression; Weiterverarbeitungsalgorithmen; Darstellungsalgorithmen; funktionelle Bildgebung; JPEG2000; lossy compression; irreversible compression; Post-Procesing; JPEG2000; functional imaging; Medical sciences Medicine

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

APA (6^th Edition):

Friese, C. F. (2014). Analyse zur Auswirkung der irreversiblen Wavelet-Kompression (JPEG2000) auf CT-Bildverarbeitungs- und Darstellungsalgorithmen. (Doctoral Dissertation). Johannes Gutenberg Universität Mainz. Retrieved from http://ubm.opus.hbz-nrw.de/volltexte/2014/3791/

Chicago Manual of Style (16^th Edition):

Friese, Conrad Friedrich. “Analyse zur Auswirkung der irreversiblen Wavelet-Kompression (JPEG2000) auf CT-Bildverarbeitungs- und Darstellungsalgorithmen.” 2014. Doctoral Dissertation, Johannes Gutenberg Universität Mainz. Accessed April 11, 2021. http://ubm.opus.hbz-nrw.de/volltexte/2014/3791/.

MLA Handbook (7^th Edition):

Friese, Conrad Friedrich. “Analyse zur Auswirkung der irreversiblen Wavelet-Kompression (JPEG2000) auf CT-Bildverarbeitungs- und Darstellungsalgorithmen.” 2014. Web. 11 Apr 2021.

Vancouver:

Friese CF. Analyse zur Auswirkung der irreversiblen Wavelet-Kompression (JPEG2000) auf CT-Bildverarbeitungs- und Darstellungsalgorithmen. [Internet] [Doctoral dissertation]. Johannes Gutenberg Universität Mainz; 2014. [cited 2021 Apr 11]. Available from: http://ubm.opus.hbz-nrw.de/volltexte/2014/3791/.

Council of Science Editors:

Friese CF. Analyse zur Auswirkung der irreversiblen Wavelet-Kompression (JPEG2000) auf CT-Bildverarbeitungs- und Darstellungsalgorithmen. [Doctoral Dissertation]. Johannes Gutenberg Universität Mainz; 2014. Available from: http://ubm.opus.hbz-nrw.de/volltexte/2014/3791/

Temple University

3. Alvarez, Moira. Problemáticas del espacio en la narrativa hispanoamericana contemporánea (1990-2010).

Degree: PhD, 2015, Temple University

URL: http://digital.library.temple.edu/u?/p245801coll10,351448

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Spanish

My dissertation, “Problemáticas del espacio en la narrativa hispanoamericana contemporánea (1990-2010)” [Problematics of Space in Contemporary Spanish American Narrative (1990-2010)], focuses on the concept… (more)

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Spanish

My dissertation, “Problemáticas del espacio en la narrativa hispanoamericana contemporánea (1990-2010)” [Problematics of Space in Contemporary Spanish American Narrative (1990-2010)], focuses on the concept of space and its articulations in a diverse corpus of written and visual narratives by contemporary Latin American authors. The problematics of spaciality are analyzed within the specific time period encompassing the last decade of the 20th century and the first decade of the 21st century, a period in which space has emerged as an important category for understanding the present. The “spatial turn”, proposed and analyzed by Michel Foucault, David Harvey, and Edward Soja, assumes that space has become a more relevant analytical category than time, due to the emergence of new technologies and media, new forms of capital flow, and because of the preeminence of the image in contemporary times. Following Henri Lefebvre’s foundational proposal, I understand space in relation to social formation and as a product of human practices rather than as an a priori category or an abstract geometrical notion independent of subjectivity and human agency. Within this framework, the problematics of space are analyzed in a corpus that includes the novels Amuleto (1999) by Roberto Bolaño, La virgen de los sicarios (1994) by Fernando Vallejo, and El asco. Thomas Bernhard en San Salvador (1997) by Horacio Castellanos Moya, and two films, Los rubios (2003) directed by Albertina Carri, and La teta asustada (2009) by Claudia Llosa. The first chapter of the dissertation lays out the theoretical framework of the concept of space and the specific socio-economical characteristics of the studied time period. The second chapter analyzes the enclosed space of Amuleto in the context of Mexico’s 1968 Tlatelolco Massacre, and proposes that a “space of the abyss” emerges with the death of a Latin American generation and the fall of the utopias in the 1960s. The third chapter compares and contrasts the films La teta asustada and Los rubios with respect to the theme of postmemory in the periods following the internal conflict in Peru and the military dictatorship in Argentina. The “space of postmemory” that arises in both films relates to the interplay between the absence/presence of the bodies of the parents – who lived the traumatic events – and the second generation that inherits the trauma. The fourth chapter examines the “spaces of escape” that emerge from La virgen de los sicarios and El asco as a possibility of escape for protagonists who face collapsed cities and states: Medellin after the death of Pablo Escobar, and San Salvador after the end of the Civil War. The three configurations of space that arise from the corpus – “space of the abyss”, “space of postmemory”, and “space of escape” – articulate crucial issues of contemporary Latin America such as the fall of modernizing utopias, trauma, postmemory, disenchantment, and the failure of the liberal state. They also bring to light three key features of contemporary spatiality: the…

Advisors/Committee Members: Ramírez Franco, Sergio;, Morell, Hortensia R., Aldarondo, Hiram, Bueno, Raúl;.

Subjects/Keywords: Latin American studies; Literature;

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

APA (6^th Edition):

Alvarez, M. (2015). Problemáticas del espacio en la narrativa hispanoamericana contemporánea (1990-2010). (Doctoral Dissertation). Temple University. Retrieved from http://digital.library.temple.edu/u?/p245801coll10,351448

Chicago Manual of Style (16^th Edition):

Alvarez, Moira. “Problemáticas del espacio en la narrativa hispanoamericana contemporánea (1990-2010).” 2015. Doctoral Dissertation, Temple University. Accessed April 11, 2021. http://digital.library.temple.edu/u?/p245801coll10,351448.

MLA Handbook (7^th Edition):

Alvarez, Moira. “Problemáticas del espacio en la narrativa hispanoamericana contemporánea (1990-2010).” 2015. Web. 11 Apr 2021.

Vancouver:

Alvarez M. Problemáticas del espacio en la narrativa hispanoamericana contemporánea (1990-2010). [Internet] [Doctoral dissertation]. Temple University; 2015. [cited 2021 Apr 11]. Available from: http://digital.library.temple.edu/u?/p245801coll10,351448.

Council of Science Editors:

Alvarez M. Problemáticas del espacio en la narrativa hispanoamericana contemporánea (1990-2010). [Doctoral Dissertation]. Temple University; 2015. Available from: http://digital.library.temple.edu/u?/p245801coll10,351448

University of Limerick

4. de Montmorency Sutherland, Luke. Influence of a physical constraint combined with uphill quenching on residual stresses in 7000 series aluminium alloys.

Degree: 2020, University of Limerick

URL: http://hdl.handle.net/10344/9316

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peer-reviewed

When quenching heat treatable aluminium alloys, the interior of a sample cools at a different rate than that of the surface. Post quench this… (more)

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peer-reviewed

When quenching heat treatable aluminium alloys, the interior of a sample cools at a different rate than that of the surface. Post quench this usually forms a triaxial tensile stress in the interior and a biaxial compressive stress on the surface of the sample. These residual stresses can have sufficient magnitudes to cause distortion of parts when being machined. Uphill quenching is a thermal method that relieves residual stresses post conventional quenching. This technique maintains the dimensional properties of the sample, unlike mechanical procedures such as cold compression and stretching. Despite uphill quenching being a time consuming and expensive method it does have industrial applications, as it allows parts to maintain all of the desired mechanical properties associated with rapid quenching. Uphill quenching could be used on long aluminium aircraft simple geometric pieces such as rolled wing spars or extruded stringers. The aim of this study is to quantify the magnitude of residual stresses that can be relieved during a variation of uphill quenching heat treatment. The alloys tested are 7000 series aluminium alloys. The uphill quenching method is cooling a test piece to -197 ℃ in liquid nitrogen post solution heat treatment and quenching, then rapidly reheating in boiling water or high pressure steam. This study added a variation to the standard uphill quench. The test piece was thermally constrained along its long axis during the reheating phase of uphill quenching. A simple rectilinear shaped test piece was chosen to ensure uniform stress redistribution. Cold compression tests were also performed as a comparison to the effects of constrained thermal expansion. Post quench delay experiments were done to see at what time would be the most optimal for mechanically relieving the test pieces of the residual stress magnitudes. The surface residual stresses were determined by X-ray diffraction using the sin2Ѱ method. Vickers hardness tests at varying temperatures and artificial ageing response tests were undertaken to study the mechanical properties during the reheating phase. Micro and hot caustic macro etching was carried out to see the shape, size and pattern of the microstructure of a test piece post an uphill quenching process. The thermally constrained uphill quenching methods using boiling water and steam were relieved on the surface about 60 and 66 % in the longitudinal orientation and 30 and 38 % short transverse orientation respectively. The majority of this relief resulted from the physical constraint. Constrained uphill quenching gave better residual stress relief than standard uphill quenching practices. Cold compression results showed that a compression of 0.6 % is enough to relieve 90 % of surface residual stresses. Post quench delay showed no clear results other than keeping the time of mechanical relief constant. During the reheating phase of uphill quenching it is best to relieve as much residual stress within a minute of being subjected to elevated temperatures, as the…

Advisors/Committee Members: Robinson, Jeremy, Tanner, David A..

Subjects/Keywords: uphill quenching; constrained thermal expansion; cold compression; post quench delay; residual stresses; varying temperature hardness; ageing response hardness; X-ray diffraction

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

APA (6^th Edition):

de Montmorency Sutherland, L. (2020). Influence of a physical constraint combined with uphill quenching on residual stresses in 7000 series aluminium alloys. (Thesis). University of Limerick. Retrieved from http://hdl.handle.net/10344/9316

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):

de Montmorency Sutherland, Luke. “Influence of a physical constraint combined with uphill quenching on residual stresses in 7000 series aluminium alloys.” 2020. Thesis, University of Limerick. Accessed April 11, 2021. http://hdl.handle.net/10344/9316.

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

MLA Handbook (7^th Edition):

de Montmorency Sutherland, Luke. “Influence of a physical constraint combined with uphill quenching on residual stresses in 7000 series aluminium alloys.” 2020. Web. 11 Apr 2021.

Vancouver:

de Montmorency Sutherland L. Influence of a physical constraint combined with uphill quenching on residual stresses in 7000 series aluminium alloys. [Internet] [Thesis]. University of Limerick; 2020. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/10344/9316.

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

Council of Science Editors:

de Montmorency Sutherland L. Influence of a physical constraint combined with uphill quenching on residual stresses in 7000 series aluminium alloys. [Thesis]. University of Limerick; 2020. Available from: http://hdl.handle.net/10344/9316

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

Uppsala University

5. Nilsson, Elin. Graderade kompressionsstrumpors preventiva effekt för djup ventrombos och posttrombotiskt syndrom.

Degree: Public Health and Caring Sciences, 2020, Uppsala University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-408302

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Bakgrund: Djup ventrombos (DVT) är en allvarlig komplikation postoperativt och kan leda till ett livshotande tillstånd för patienten. Graderade kompressionsstrumpor (GCS) används på många… (more)

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Bakgrund: Djup ventrombos (DVT) är en allvarlig komplikation postoperativt och kan leda till ett livshotande tillstånd för patienten. Graderade kompressionsstrumpor (GCS) används på många postoperativa avdelningar tillsammans med andra profylaktiska åtgärder för att förebygga utvecklingen av DVT. Kompressionsstrumpor används även till att förebygga posttrombotiskt syndrom (PTS) efter en DVT. PTS kan utvecklas på grund av att de venösa klaffarna skadas vid en DVT, till följd stockar sig blodet och ödem bildas vilket leder till försämrad näring- och syretillförsel till vävnaderna. Syfte: Syftet var att genom en litteraturstudie undersöka om kompressionsstrumpor hade någon effekt för att förebygga DVT postoperativt samt om kompressionsstrumpor hade någon effekt att förebygga PTS efter en DVT. Metod: Litteraturstudie som baserads på 11 RCT studier. Resultat: GCS utan andra profylaktiska åtgärder visade sig ha en god effekt för att undvika utvecklingen av DVT på patienter som genomgått en operation. Däremot visade sig användandet av GCS i kombination med andra beprövade profylax inte ha någon större effekt för att reducera uppkomsten av DVT ytterligare. Resultatet angående GCS effekt för att undvika utvecklingen av PTS visade ingen entydighet. Slutsats: GCS har en förebyggande effekt för att undvika uppkomsten av DVT. Användningen av GCS i kombination med andra profylax potentierar däremot inte effekten av preventionen för DVT. GCS verkan för att förebygga uppkomsten av PTS är inte entydigt och flera studier behövs för att se evidens kring detta.

ABSTRACT Background: Deep vein thrombosis (DVT) is a serious complication postoperatively and can lead to a life threatening condition for the patient. Graded compression stockings (GCS) are used in many post-operative departments along with other prophylactic measures to prevent the development of DVT. Compression stockings are also used to prevent postthrombotic syndrome (PTS) after a DVT. PTS can develop because the venous valves are damaged by a DVT, as a result, the blood is stored and edema is formed, which leads to poor nutritional and oxygen supply to the tissues. Aim: The aim of the literature study was to investigate whether compression stockings had any effect in preventing DVT postoperatively, and also whether the compression stockings had any effect in preventing PTS after a DVT. Method: Literature study based on 11 RCT studies. Results: GCS without other prophylactic measures was found to have a good effect in avoiding the development of DVT in patients who underwent surgery. However, the use of GCS in combination with other proven prophylaxis was found to have no significant effect in further reducing the onset of DVT. The results regarding the GCS effect to avoid the development of PTS showed no…

Subjects/Keywords: Deep vein thrombosis; compression stockings; complications; prophylaxis; post-operative; postthrombotic syndrome; Djup ventrombos; kompressionsstrumpor; komplikationer; profylax; postoperativt; posttrombotiskt syndrom; Nursing; Omvårdnad

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

APA (6^th Edition):

Nilsson, E. (2020). Graderade kompressionsstrumpors preventiva effekt för djup ventrombos och posttrombotiskt syndrom. (Thesis). Uppsala University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-408302

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):

Nilsson, Elin. “Graderade kompressionsstrumpors preventiva effekt för djup ventrombos och posttrombotiskt syndrom.” 2020. Thesis, Uppsala University. Accessed April 11, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-408302.

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

MLA Handbook (7^th Edition):

Nilsson, Elin. “Graderade kompressionsstrumpors preventiva effekt för djup ventrombos och posttrombotiskt syndrom.” 2020. Web. 11 Apr 2021.

Vancouver:

Nilsson E. Graderade kompressionsstrumpors preventiva effekt för djup ventrombos och posttrombotiskt syndrom. [Internet] [Thesis]. Uppsala University; 2020. [cited 2021 Apr 11]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-408302.

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

Council of Science Editors:

Nilsson E. Graderade kompressionsstrumpors preventiva effekt för djup ventrombos och posttrombotiskt syndrom. [Thesis]. Uppsala University; 2020. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-408302

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

6. Hort, Ondřej. High harmonic generation with high energy femtosecond pulses : Génération d’harmoniques d’ordres élevés avec des impulsions femtosecondes de haute énergie.

Degree: Docteur es, Lasers, matière et nanosciences, 2014, Bordeaux

URL: http://www.theses.fr/2014BORD0097

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Nous présentons nos travaux sur la génération d’harmoniques élevée (HHG) avec des impulsions térawatt femtosecondes. Nous avons effectué l’HHG avec les impulsions fondamentales de haute… (more)

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Nous présentons nos travaux sur la génération d’harmoniques élevée (HHG) avec des impulsions térawatt femtosecondes. Nous avons effectué l’HHG avec les impulsions fondamentales de haute énergie et caractérisé l’émission de XUV spatialement et spectralement de manière monocoup et nous avons observé plusieurs structures dans le champ lointain. Ces structures sont très robustes et reproductibles et ont été observés dans de nombreux types de gaz et des géométries de génération. Sans caractérisation monocoup spatiale et spectrale les structures ne sont pas visibles. Nous avons développé des simulations simples pour identifier ces structures et nous avons pu observer des structures similaires. Nous les avons identifiés comme étant liées à la cohérence spatiale de la source XUV et la diffraction dans le champ lointain. Dans le champ proche, la phase et l’amplitude harmonique évoluent spatialement et temporellement et leurs profils sont fortement modulés. Ces profils modulés diffractent et créent des spectres structurés dans le champ lointain. Nous avons observé que la propagation dans un milieu générateur fin a peu d’influence sur les structures. Nous démontrons une mise en forme spatiale de l’impulsion fondamentale via l’optique adaptative et leur avantage pour HHG. Une optique adaptative nous permet d’avoir un faisceau à profil de phase régulier. Un tel faisceau est utilisé pour HHG avec un faisceau de grand diamètre et contrôle du faisceau XUV est démontrée. Nous avons développé une technique de post-compression de haute énergie, et nous avons obtenu des impulsionsde 10 fs et 10 mJ dans un profil quasi gaussien. La technique repose sur l’automodulation de phase induite par l’ionisation et est compatible avec des impulsions niveau TW de haute énergie. Nous avons effectué des HHG avec ces impulsions et obtenu des spectres XUV quasi continu avec des structures spatiales et spectrales. Nous avons effectué des simulations simples etdes simulations de SFA et nous avons observé des structures similaires même sans prendre en compte la propagation dans le milieu.

We present our work on high harmonic generation with TW femtosecond pulses. We performed HHG with high energy femtosecond pulses and characterize the generated XUV emission spatially and spectrally at the single-shot basis and we observed many structures in spatially resolved XUV spectra in the far field. Those structures are very robust and reproducible and have been observed in many different gases and generation geometries. Without spatial and spectral characterization on the single-shot basis the structures are not visible. We developed simple simulations to identify those structures and we observed similar structures as experimentally. We identified them as a result of spatial coherence of the XUV source and the diffraction to the far field. In the near field, the harmonic amplitude and phase are spatially and temporally dependent and their profiles are strongly modulated. Such modulated profiles diffract to structured spatially resolved spectra in the far field.…

Advisors/Committee Members: Constant, Eric (thesis director).

Subjects/Keywords: Génération d’harmoniques d’ordres élevés; Lasers femtosecondes; Impulsions attosecondes; Post-compression par ionisation; Structures XUV spatiales et spectrales; High harmonic generation; Femtosecond lasers; Attosecond pulses; Ionization induced post-compression; Spatial and spectral XUV structures

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

APA (6^th Edition):

Hort, O. (2014). High harmonic generation with high energy femtosecond pulses : Génération d’harmoniques d’ordres élevés avec des impulsions femtosecondes de haute énergie. (Doctoral Dissertation). Bordeaux. Retrieved from http://www.theses.fr/2014BORD0097

Chicago Manual of Style (16^th Edition):

Hort, Ondřej. “High harmonic generation with high energy femtosecond pulses : Génération d’harmoniques d’ordres élevés avec des impulsions femtosecondes de haute énergie.” 2014. Doctoral Dissertation, Bordeaux. Accessed April 11, 2021. http://www.theses.fr/2014BORD0097.

MLA Handbook (7^th Edition):

Hort, Ondřej. “High harmonic generation with high energy femtosecond pulses : Génération d’harmoniques d’ordres élevés avec des impulsions femtosecondes de haute énergie.” 2014. Web. 11 Apr 2021.

Vancouver:

Hort O. High harmonic generation with high energy femtosecond pulses : Génération d’harmoniques d’ordres élevés avec des impulsions femtosecondes de haute énergie. [Internet] [Doctoral dissertation]. Bordeaux; 2014. [cited 2021 Apr 11]. Available from: http://www.theses.fr/2014BORD0097.

Council of Science Editors:

Hort O. High harmonic generation with high energy femtosecond pulses : Génération d’harmoniques d’ordres élevés avec des impulsions femtosecondes de haute énergie. [Doctoral Dissertation]. Bordeaux; 2014. Available from: http://www.theses.fr/2014BORD0097

7. Maghraoui, Ahmed. Génération d'harmoniques d'ordre élevé pour l'étude de la dynamique des charges et de l'aimantation de films de cobalt : High harmonic generation for the study of the demagnetization dynamics of cobalt films.

Degree: Docteur es, Physique, 2015, Université de Strasbourg

URL: http://www.theses.fr/2015STRAE010

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L’objectif de cette est de développer une source harmonique permettant de couvrir la gamme d’énergie 50 -70 eV du spectre électromagnétique par la génération d’harmoniques… (more)

Subjects/Keywords: Magnéto-optiques; Dynamique d'aimantation; Amplification à dérive de fréquence; Post-compression; Impulsions femtosecondes; Génération d'harmoniques d'ordre élevé; Rayonnement XUV; Accord de phase; Magnetization dynamics; Femtosecond implusions; Harmonic generation; 537.6

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

APA (6^th Edition):

Maghraoui, A. (2015). Génération d'harmoniques d'ordre élevé pour l'étude de la dynamique des charges et de l'aimantation de films de cobalt : High harmonic generation for the study of the demagnetization dynamics of cobalt films. (Doctoral Dissertation). Université de Strasbourg. Retrieved from http://www.theses.fr/2015STRAE010

Chicago Manual of Style (16^th Edition):

Maghraoui, Ahmed. “Génération d'harmoniques d'ordre élevé pour l'étude de la dynamique des charges et de l'aimantation de films de cobalt : High harmonic generation for the study of the demagnetization dynamics of cobalt films.” 2015. Doctoral Dissertation, Université de Strasbourg. Accessed April 11, 2021. http://www.theses.fr/2015STRAE010.

MLA Handbook (7^th Edition):

Maghraoui, Ahmed. “Génération d'harmoniques d'ordre élevé pour l'étude de la dynamique des charges et de l'aimantation de films de cobalt : High harmonic generation for the study of the demagnetization dynamics of cobalt films.” 2015. Web. 11 Apr 2021.

Vancouver:

Maghraoui A. Génération d'harmoniques d'ordre élevé pour l'étude de la dynamique des charges et de l'aimantation de films de cobalt : High harmonic generation for the study of the demagnetization dynamics of cobalt films. [Internet] [Doctoral dissertation]. Université de Strasbourg; 2015. [cited 2021 Apr 11]. Available from: http://www.theses.fr/2015STRAE010.

Council of Science Editors:

Maghraoui A. Génération d'harmoniques d'ordre élevé pour l'étude de la dynamique des charges et de l'aimantation de films de cobalt : High harmonic generation for the study of the demagnetization dynamics of cobalt films. [Doctoral Dissertation]. Université de Strasbourg; 2015. Available from: http://www.theses.fr/2015STRAE010

Penn State University

8. Borz, Meghan Justine. GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES.

Degree: 2016, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/2j62s484w

► In-cylinder strategies such as advanced fuel injection schedules and optimal piston bowl designs are often utilized in diesel combustion for to improve efficiency and/or reduce… (more)

▼ In-cylinder strategies such as advanced fuel injection schedules and optimal piston bowl designs are often utilized in diesel combustion for to improve efficiency and/or reduce emissions. The large design space for injection schedules makes choosing the optimal schedule for an engine particularly challenging. Additionally, experimental in-engine studies of advanced injection schedules are time-consuming and costly. Gas jet experiments can provide a good approximation for the behavior of diesel jets and more tests can be conducted in a shorter period of time without incurring the costs of an engine research facility. The goal of this work is to gain a further understanding of some of the fundamental fluid mechanics of multiple injections, jet-jet interactions, and jets impinging on surfaces. Gas jet experiments are conducted using z-schlieren and acetone tracer planar laser-induced fluorescence (PLIF). Three studies are conducted focusing on free jets, multiple jet interactions, jet-jet interaction, and bowl geometry effects. The first study is a comparison of penetration results for helium gas jets with penetration results for vaporizing and non-vaporizing sprays, which shows that by non-dimensionalizing the results of gas jet experiments, the penetration curve follows a similar trend to the non-dimensionalized penetration curve for vaporizing and non-vaporizing liquid sprays. The second study explores the fluid mechanic interactions between multiple injections and the effects of injection duration and dwell. The schlieren results of the multiple-injection studies showed that before the end of injection (EOI) the non-dimensional jet-tip penetration was not significantly different for the first and second injection, however, the average dispersion half angle during the quasi-steady portion of injection was higher for the first injection than for the second injection. There are two multiple-injection cases where the average dispersion half angle of the second injection is higher than that of the first injection by a statistically significant amount. These differences in jet dispersion angle are indicative of differences in mixing and entrainment during the first and second injections. Future studies with acetone-PLIF will allow the concentration to be quantified and differences in the jet composition for the first and second injections in multiple-injection schemes to be compared. The last study focuses on the effects of piston bowl geometry and the angle between interacting jets. The effects of the geometry on fluid recirculation and mixing are studied using schlieren and PLIF with jets of acetone vapor and air and two different piston bowl designs. The results showed that a deeper bowl and wider angle between the jets allows for improved mixing and air utilization. Advisors/Committee Members: Jacqueline Antonia O'Connor, Thesis Advisor/Co-Advisor, Daniel Connell Haworth, Committee Member, Mary I Frecker, Committee Member.

Subjects/Keywords: gas jet; compression ignition; schlieren; jet-tip penetration; multiple injections; pilot injection; post injection; split injection; laser induced fluorescence; jet-jet interaction; piston geometry

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

APA (6^th Edition):

Borz, M. J. (2016). GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/2j62s484w

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):

Borz, Meghan Justine. “GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES.” 2016. Thesis, Penn State University. Accessed April 11, 2021. https://submit-etda.libraries.psu.edu/catalog/2j62s484w.

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

MLA Handbook (7^th Edition):

Borz, Meghan Justine. “GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES.” 2016. Web. 11 Apr 2021.

Vancouver:

Borz MJ. GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES. [Internet] [Thesis]. Penn State University; 2016. [cited 2021 Apr 11]. Available from: https://submit-etda.libraries.psu.edu/catalog/2j62s484w.

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

Council of Science Editors:

Borz MJ. GAS JET STUDIES FOR THE CHARACTERIZATION OF ADVANCED INJECTION SCHEDULES AND BOWL DESIGN IN DIESEL ENGINES. [Thesis]. Penn State University; 2016. Available from: https://submit-etda.libraries.psu.edu/catalog/2j62s484w

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

Queensland University of Technology

9. Shirmohammadi, Maryam. Process modelling and simulation of tissue damage during mechanical peeling of pumpkin as a tough skinned vegetable.

Degree: 2014, Queensland University of Technology

URL: https://eprints.qut.edu.au/67921/

► Food waste is a current challenge that both developing and developed countries face. This project applied a novel combination of available methods in Mechanical, agricultural… (more)

Subjects/Keywords: Post harvesting Loss; Food Processing; Finite Element Analysis; Constitutive Modelling; Tensile testing; Compression Testing; Indentation Testing; Mechanical Properties; Physical Properties; Agricultural Crops

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

APA (6^th Edition):

Shirmohammadi, M. (2014). Process modelling and simulation of tissue damage during mechanical peeling of pumpkin as a tough skinned vegetable. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/67921/

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):

Shirmohammadi, Maryam. “Process modelling and simulation of tissue damage during mechanical peeling of pumpkin as a tough skinned vegetable.” 2014. Thesis, Queensland University of Technology. Accessed April 11, 2021. https://eprints.qut.edu.au/67921/.

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

MLA Handbook (7^th Edition):

Shirmohammadi, Maryam. “Process modelling and simulation of tissue damage during mechanical peeling of pumpkin as a tough skinned vegetable.” 2014. Web. 11 Apr 2021.

Vancouver:

Shirmohammadi M. Process modelling and simulation of tissue damage during mechanical peeling of pumpkin as a tough skinned vegetable. [Internet] [Thesis]. Queensland University of Technology; 2014. [cited 2021 Apr 11]. Available from: https://eprints.qut.edu.au/67921/.

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

Council of Science Editors:

Shirmohammadi M. Process modelling and simulation of tissue damage during mechanical peeling of pumpkin as a tough skinned vegetable. [Thesis]. Queensland University of Technology; 2014. Available from: https://eprints.qut.edu.au/67921/

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

Cardiff University

10. Khayyat, Hassan A. Conceptual design and mechanisms for foldable pyramidal plated structures.

Degree: PhD, 2008, Cardiff University

URL: http://orca.cf.ac.uk/54739/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.584340

► In spite of the presence of much research in the field of foldable structures whose applications have covered most of the requirements of academic and… (more)

Subjects/Keywords: 624.1; Foldable pyramid, Plate Structure, Folding Mechanism, Post-compression technique

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APA (6^th Edition):

Khayyat, H. A. (2008). Conceptual design and mechanisms for foldable pyramidal plated structures. (Doctoral Dissertation). Cardiff University. Retrieved from http://orca.cf.ac.uk/54739/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.584340

Chicago Manual of Style (16^th Edition):

Khayyat, Hassan A. “Conceptual design and mechanisms for foldable pyramidal plated structures.” 2008. Doctoral Dissertation, Cardiff University. Accessed April 11, 2021. http://orca.cf.ac.uk/54739/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.584340.

MLA Handbook (7^th Edition):

Khayyat, Hassan A. “Conceptual design and mechanisms for foldable pyramidal plated structures.” 2008. Web. 11 Apr 2021.

Vancouver:

Khayyat HA. Conceptual design and mechanisms for foldable pyramidal plated structures. [Internet] [Doctoral dissertation]. Cardiff University; 2008. [cited 2021 Apr 11]. Available from: http://orca.cf.ac.uk/54739/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.584340.

Council of Science Editors:

Khayyat HA. Conceptual design and mechanisms for foldable pyramidal plated structures. [Doctoral Dissertation]. Cardiff University; 2008. Available from: http://orca.cf.ac.uk/54739/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.584340

Brno University of Technology

11. Bodeček, Kamil. Komprese obrazu v interaktivních aplikacích digitálního televizního vysílání: Image compression in interactive applications in digital video broadcasting.

Degree: 2019, Brno University of Technology

URL: http://hdl.handle.net/11012/25780

► Compressed images are used very frequently in interactive applications in digital video broadcasting. New methods increasing efficiency of the image transmission in digital video broadcasting… (more)

Subjects/Keywords: komprese obrazu; digitální televizní vysílání; JPEG. JPEG2000; H.264; filtrace obrazu; image compression; digital television broadcasting; JPEG; JPEG2000; H.264; image post-processing

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

APA (6^th Edition):

Bodeček, K. (2019). Komprese obrazu v interaktivních aplikacích digitálního televizního vysílání: Image compression in interactive applications in digital video broadcasting. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/25780

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):

Bodeček, Kamil. “Komprese obrazu v interaktivních aplikacích digitálního televizního vysílání: Image compression in interactive applications in digital video broadcasting.” 2019. Thesis, Brno University of Technology. Accessed April 11, 2021. http://hdl.handle.net/11012/25780.

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

MLA Handbook (7^th Edition):

Bodeček, Kamil. “Komprese obrazu v interaktivních aplikacích digitálního televizního vysílání: Image compression in interactive applications in digital video broadcasting.” 2019. Web. 11 Apr 2021.

Vancouver:

Bodeček K. Komprese obrazu v interaktivních aplikacích digitálního televizního vysílání: Image compression in interactive applications in digital video broadcasting. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/11012/25780.

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

Council of Science Editors:

Bodeček K. Komprese obrazu v interaktivních aplikacích digitálního televizního vysílání: Image compression in interactive applications in digital video broadcasting. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/25780

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

University of Lund

12. Louisy, Maite. Generation of Ultrashort Pulses – From Femtoseconds to Attoseconds.

Degree: 2017, University of Lund

URL: https://lup.lub.lu.se/record/be77d45d-1e74-4932-b37f-1d4cf068d731 ; https://portal.research.lu.se/ws/files/35813976/Louisy_Dissertation_2017.pdf

► Electronic dynamics takes place on the attosecond timescale and can thus only be studied using a tool with attosecond temporal resolution. High harmonic generation (HHG)… (more)

Subjects/Keywords: Engineering and Technology; Attosecond; Femtosecond; Ultrashort laser pulses; Ultrafast optics; High-order harmonic generation; extreme ultraviolet; Post-compression; Hollow-core capillary; d-scan; Optical gating; Fysicumarkivet A:2017:Louisy

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

APA (6^th Edition):

Louisy, M. (2017). Generation of Ultrashort Pulses – From Femtoseconds to Attoseconds. (Doctoral Dissertation). University of Lund. Retrieved from https://lup.lub.lu.se/record/be77d45d-1e74-4932-b37f-1d4cf068d731 ; https://portal.research.lu.se/ws/files/35813976/Louisy_Dissertation_2017.pdf

Chicago Manual of Style (16^th Edition):

Louisy, Maite. “Generation of Ultrashort Pulses – From Femtoseconds to Attoseconds.” 2017. Doctoral Dissertation, University of Lund. Accessed April 11, 2021. https://lup.lub.lu.se/record/be77d45d-1e74-4932-b37f-1d4cf068d731 ; https://portal.research.lu.se/ws/files/35813976/Louisy_Dissertation_2017.pdf.

MLA Handbook (7^th Edition):

Louisy, Maite. “Generation of Ultrashort Pulses – From Femtoseconds to Attoseconds.” 2017. Web. 11 Apr 2021.

Vancouver:

Louisy M. Generation of Ultrashort Pulses – From Femtoseconds to Attoseconds. [Internet] [Doctoral dissertation]. University of Lund; 2017. [cited 2021 Apr 11]. Available from: https://lup.lub.lu.se/record/be77d45d-1e74-4932-b37f-1d4cf068d731 ; https://portal.research.lu.se/ws/files/35813976/Louisy_Dissertation_2017.pdf.

Council of Science Editors:

Louisy M. Generation of Ultrashort Pulses – From Femtoseconds to Attoseconds. [Doctoral Dissertation]. University of Lund; 2017. Available from: https://lup.lub.lu.se/record/be77d45d-1e74-4932-b37f-1d4cf068d731 ; https://portal.research.lu.se/ws/files/35813976/Louisy_Dissertation_2017.pdf

Colorado School of Mines

13. Kias, Evan M. C. Investigation of unstable failure in underground coal mining using the discrete element method.

Degree: PhD, Mining Engineering, 2013, Colorado School of Mines

URL: http://hdl.handle.net/11124/18

► Unstable failure in underground coal mining is the sudden and violent ejection of coal from mine walls and pillars into the mine opening. This thesis… (more)

▼ Unstable failure in underground coal mining is the sudden and violent ejection of coal from mine walls and pillars into the mine opening. This thesis demonstrates the use of the discrete element method to simulate stable and unstable modes of compressive failure of a western U.S. coal. Two discrete element models are evaluated for their ability to simulate unstable and stable compressive failure using the discrete element program Particle Flow Code in Two Dimensions (PFC2D): the bonded particle model and the displacement softening model. Compressive strength tests show that the displacement softening model is better suited for unstable failure studies based on consistent behavior in stable and unstable modes of failure and a post-peak softening characteristic that is independent of the loading rate. A set of model behaviors, called indicators, are analyzed on their ability to distinguish the stability of failure in a series of unconfined compression tests and then a series slender pillar compressive strength tests. Generally, the indicators show consistent values for stable failures and increasing magnitude with increasing levels of instability. A grid based measurement technique is used to observe indicator behavior and model damage spatially. The work by the damping mechanism, kinetic energy, and the mean unbalanced force are used to analyze pillar edge failure in a model with excavation induced loading conditions. The indicators reveal unstable failure events, and a comparison between stable and unstable mining steps show that the indicators can be used to detect local instabilities on, such as pillar rib failure. Grid based measurements show that the unstable failure is initiated due to a single mining step and that failure occurred along a diagonal failure plane originating from the mine face similar to that seen in practice. Unstable failures show highly localized planes of failure while stable pillar failure is more dispersed. Future application of the techniques developed in this thesis include more in depth study of factors influencing unstable failures in coal mines including the mine/coal seam contact condition and depth. Advisors/Committee Members: Ozbay, M. Ugur (advisor), Nakagawa, Masami (committee member), Mustoe, Graham G. W. (committee member), Berger, John R. (committee member), Higgins, Jerry D. (committee member).

Subjects/Keywords: unstable failure; rockburst; post peak behavior; displacement softening model; discrete element method; bonded particle model; Rock bursts; Coal mines and mining; Rock mechanics; Particles – Mathematical models; Materials – Compression testing

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

APA (6^th Edition):

Kias, E. M. C. (2013). Investigation of unstable failure in underground coal mining using the discrete element method. (Doctoral Dissertation). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/18

Chicago Manual of Style (16^th Edition):

Kias, Evan M C. “Investigation of unstable failure in underground coal mining using the discrete element method.” 2013. Doctoral Dissertation, Colorado School of Mines. Accessed April 11, 2021. http://hdl.handle.net/11124/18.

MLA Handbook (7^th Edition):

Kias, Evan M C. “Investigation of unstable failure in underground coal mining using the discrete element method.” 2013. Web. 11 Apr 2021.

Vancouver:

Kias EMC. Investigation of unstable failure in underground coal mining using the discrete element method. [Internet] [Doctoral dissertation]. Colorado School of Mines; 2013. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/11124/18.

Council of Science Editors:

Kias EMC. Investigation of unstable failure in underground coal mining using the discrete element method. [Doctoral Dissertation]. Colorado School of Mines; 2013. Available from: http://hdl.handle.net/11124/18

14. Martão, Carolina. Compósitos de polipropileno reciclado reforçados com fibras de coco.

Degree: 2018, Brazil

URL: http://biblioteca.ufabc.edu.br/index.php?codigo_sophia=111427

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Orientadora: Profª Dra. Márcia Aparecida da Silva Spinacé

Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Nanociências e Materiais Avançados, Santo André,… (more)

▼

Orientadora: Profª Dra. Márcia Aparecida da Silva Spinacé

Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Nanociências e Materiais Avançados, Santo André, 2018.

Neste trabalho foram preparados por moldagem por compressao os compositos de polipropileno pos-consumo (PPpc) com 1,75; 3,5; 7 e 20 % em massa (m/m) de fibras de coco (FC) longas e curtas, visando melhorar as propriedades mecanicas do PPpc. As FC foram submetidas aos tratamentos em ultrassom, em autoclave, e em solucao alcalina de hidroxido de sodio e sulfito de sodio (TA). As FC longas foram dispostas unidirecionalmente, bidirecionalmente e aleatoriamente na matriz polimerica, e as FC curtas aleatoriamente. As FC com e sem o TA foram caracterizadas por meio de analise temogravimetrica, espectroscopia de infravermelho (FTIR) e microscopia eletronica de varredura (MEV). A influencia do teor, tratamento e orientacao das FC nas propriedades mecanicas dos compositos foi avaliada por meio de ensaios de tracao. A analise de FTIR sugeriu a remocao parcial da hemicelulose das FC submetidas a todos os tratamentos. O aumento da rugosidade na superficie da FC tratada (TA) foi verificado por meio de MEV. Foram usados PPpc moido com diametro medio de 1,6 (} 0,4) mm que permitiu a confeccao de compositos na forma de filmes com espessura de 1 mm reforcados com FC com diametro medio na faixa de 150-300 ¿Êm. As FC apresentaram teor de umidade em torno de 12 % m/m que pode ser removida por 25 min. O tratamento quimico das fibras que promoveu o melhor desempenho mecanico nos compositos foi FC tratada em solucao alcalina de 3,5 M de NaOH e 0,6 M de Na2SO3. As FC tratadas e nao tratadas foram caracterizadas mostrando que ambas podem atuar como reforco em matrizes de polipropileno pos-consumo. Este aumento na performace mecanica e devido a remocao parcial da fracao amorfa da fibra lignocelulosica (hemicelulose e lignina) e ao aumento da rugosidade superficial das fibras tratadas que pode promover intertravamento mecanico entre a FC e a matriz de PPpc. Dessa forma, a utilizacao de FC tratadas como reforco em matriz de polipropileno pos-consumo e uma alternativa, pois resultou em um material de diferentes propriedades dos componentes puros. Portanto, e uma opcao para futuras aplicacoes alem de contribuir na preservacao do meio ambiente. Possiveis aplicacoes na construcao civil e na producao de artefatos gerais como utensilios, calcados e etc.

In this work the post-consumption polypropylene composites (PPpc) with 1.75; 3.5; 7 and 20 wt % by mass of long and short coconut fibers (FC), aiming to improve the mechanical properties of PPpc. The FC was submitted to ultrasonic, autoclave and alkaline solutions of sodium hydroxide and sodium sulfite (TA). The long FCs were arranged unidirectionally, bidirectionally and randomly in the polymer matrix, and the short FC randomly. The FC with and without the TA were characterized by means of thermogravimetric analysis, infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The influence…

Advisors/Committee Members: Spinacé, Márcia Aparecida da Silva, Chinellato, Anne Cristine, Torin, Rondes Ferreira da Silva.

Subjects/Keywords: COMPÓSITO POLIMÉRICO; FIBRAS DE COCO; POLIPROPILENO PÓS-CONSUMO; MOLDAGEM POR COMPRESSÃO; POLYMER COMPOSITES; COCONUT FIBERS; POST-CONSUMER POLYPROPYLENE; COMPRESSION MOLDING; PROGRAMA DE PÓS-GRADUAÇÃO EM NANOCIÊNCIAS E MATERIAIS AVANÇADOS - UFABC

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

APA (6^th Edition):

Martão, C. (2018). Compósitos de polipropileno reciclado reforçados com fibras de coco. (Masters Thesis). Brazil. Retrieved from http://biblioteca.ufabc.edu.br/index.php?codigo_sophia=111427

Chicago Manual of Style (16^th Edition):

Martão, Carolina. “Compósitos de polipropileno reciclado reforçados com fibras de coco.” 2018. Masters Thesis, Brazil. Accessed April 11, 2021. http://biblioteca.ufabc.edu.br/index.php?codigo_sophia=111427.

MLA Handbook (7^th Edition):

Martão, Carolina. “Compósitos de polipropileno reciclado reforçados com fibras de coco.” 2018. Web. 11 Apr 2021.

Vancouver:

Martão C. Compósitos de polipropileno reciclado reforçados com fibras de coco. [Internet] [Masters thesis]. Brazil; 2018. [cited 2021 Apr 11]. Available from: http://biblioteca.ufabc.edu.br/index.php?codigo_sophia=111427.

Council of Science Editors:

Martão C. Compósitos de polipropileno reciclado reforçados com fibras de coco. [Masters Thesis]. Brazil; 2018. Available from: http://biblioteca.ufabc.edu.br/index.php?codigo_sophia=111427

Université Paris-Sud – Paris XI

15. Bourassin-Bouchet, Charles. Optiques pour les impulsions attosecondes : Optical components for attosecond pulses.

Degree: Docteur es, Physique, 2011, Université Paris-Sud – Paris XI

URL: http://www.theses.fr/2011PA112277

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Les plus brefs flashs de lumière qui puissent être produits en laboratoire actuellement ont des durées de quelques dizaines d’attosecondes (1 as = 10-18 s),… (more)

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Les plus brefs flashs de lumière qui puissent être produits en laboratoire actuellement ont des durées de quelques dizaines d’attosecondes (1 as = 10-18 s), et ne peuvent être créés que dans le domaine extrême-ultraviolet (XUV). Le développement de composants optiques capables de contrôler et de mettre en forme ce rayonnement attoseconde est crucial pour permettre à ces impulsions de se généraliser. Cette thèse porte donc sur l’étude et la réalisation de tels composants.Les impulsions attosecondes ont la particularité de comporter une dérivée de fréquence intrinsèque au processus utilisé pour leur génération. Cela a pour effet d’augmenter leur durée. Nous avons donc développé des miroirs multicouches capables d’induire une dérive de fréquence opposée sur les impulsions s’y réfléchissant, permettant ainsi de les compresser. En caractérisant les impulsions attosecondes réfléchies par ces miroirs, nous avons pour la première fois observé une telle compression des impulsions attosecondes. Nous avons également développé des miroirs multicouches théoriquement capables de compresser des impulsions sous la barre symbolique des 50 as, soit en dessous du record actuel de durée d’une impulsion lumineuse.La mesure de ces impulsions requiert leur focalisation dans un spectromètre. Or les miroirs focalisants généralement utilisés peuvent très rapidement introduire des aberrations géométriques. A l’aide de simulations numériques et d’une étude analytique, nous avons montré que ces aberrations pouvaient très fortement déformer la structure spatio-temporelle des impulsions attosecondes, provoquant une augmentation de leur durée. Enfin, nous avons montré que ces effets n’étaient pas pris en compte par les techniques actuelles de caractérisation d’impulsions attosecondes, cela pouvant amener à mesurer une impulsion attoseconde plus courte qu’elle ne l’est en réalité.

The shortest flashes of light ever produced so far have durations of a few tens of attoseconds (1 as = 10-18 s), and can only be generated in the extreme ultraviolet spectral range (XUV). Developing optical components able to control and shape such attosecond radiation is crucial to generalize the use of these light pulses. This is the topic of this work.Attosecond pulses happen to be chirped due to the physical process used to generate them. This phenomenon leads to an increase in their duration. Consequently, we developed inversely chirped multilayer mirrors, allowing one to compress the pulses during their reflection off the mirrors. By measuring these reflected pulses, we observed for the first time such a compression of attosecond pulses. Moreover, we developed another set of multilayer mirrors theoretically able to compress pulses below 50 as. That is below the current pulse duration record.Furthermore, the measurement of these pulses requires that they be focussed into a spectrometer. However, typically used focusing mirrors can add geometric aberrations. By the use of numerical simulations and thanks to an analytic study, we showed that these aberrations could…

Advisors/Committee Members: Delmotte, Franck (thesis director).

Subjects/Keywords: Impulsions XUV attosecondes; Post-compression d’impulsions; Miroirs multicouches XUV; Aberrations géométriques; Couplages spatio-temporels; Caractérisation d’impulsions attosecondes; Attosecond XUV pulses; Pulse compression; XUV multilayer mirrors; Geometric aberrations; Space-time coupling; Characterization of attosecond pulses

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

APA (6^th Edition):

Bourassin-Bouchet, C. (2011). Optiques pour les impulsions attosecondes : Optical components for attosecond pulses. (Doctoral Dissertation). Université Paris-Sud – Paris XI. Retrieved from http://www.theses.fr/2011PA112277

Chicago Manual of Style (16^th Edition):

Bourassin-Bouchet, Charles. “Optiques pour les impulsions attosecondes : Optical components for attosecond pulses.” 2011. Doctoral Dissertation, Université Paris-Sud – Paris XI. Accessed April 11, 2021. http://www.theses.fr/2011PA112277.

MLA Handbook (7^th Edition):

Bourassin-Bouchet, Charles. “Optiques pour les impulsions attosecondes : Optical components for attosecond pulses.” 2011. Web. 11 Apr 2021.

Vancouver:

Bourassin-Bouchet C. Optiques pour les impulsions attosecondes : Optical components for attosecond pulses. [Internet] [Doctoral dissertation]. Université Paris-Sud – Paris XI; 2011. [cited 2021 Apr 11]. Available from: http://www.theses.fr/2011PA112277.

Council of Science Editors:

Bourassin-Bouchet C. Optiques pour les impulsions attosecondes : Optical components for attosecond pulses. [Doctoral Dissertation]. Université Paris-Sud – Paris XI; 2011. Available from: http://www.theses.fr/2011PA112277

16. Bennett, Duane Everett, II, 1984-. Ridge Dimensional Changes: A Comparative Study of Socket Compression After Dental Extraction with No Compression.

Degree: 2013, IUPUI

URL: http://hdl.handle.net/1805/3722

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Indiana University-Purdue University Indianapolis (IUPUI)

Exodontia, or extraction of teeth, has been a well-documented dental treatment that forms one of the foundations of dentistry. The… (more)

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Indiana University-Purdue University Indianapolis (IUPUI)

Exodontia, or extraction of teeth, has been a well-documented dental treatment that forms one of the foundations of dentistry. The steps associated with extracting teeth have changed little in the last century and these steps are largely part of the dogma of dentistry. One such step is that of socket compression post-extraction. Rationale for socket compression after extraction is manifold. They include: shorter healing times, fewer dry sockets and re-approximating walls that were stretched in the elevation and delivery stages of extractions. The purpose of this study was to determine if post-extraction ridge compression negatively affected alveolar ridge dimensions when compared to sites that are not compressed post-extraction. Secondary outcome measures will identify if socket compression/re-approximation affects the rate of soft tissue closure or occurrence of alveolar osteitis. In this study, 14 subjects were recruited. Eight subjects formed the compression group, while six formed the non-compression group. The subjects in the compression group received compression of their alveolar ridges after extraction to approximate their original pre-extraction width. The subjects in the non-compression group did not receive ridge compression. Each subject had pre-extraction and post-extraction CBCT scans along with post-operative follow up visits at 1, 2, and 4 weeks post-extraction. The present investigation found that with respect to changes in ridge width, sites that were compressed did not lose significantly more dimension than those that were not. With respect to ridge height, sites that were compressed did not lose significantly more dimension than those that were not. Sites that were compressed and sites that were not, healed at approximately the same rate, with respect to soft tissue closure. While the results showed a lack of statistical significance between both groups, there appears to be a trend towards the ridge compression group having a smaller ridge width. Such a trend was not noted with soft tissue closure, thereby invalidating the rationale for socket compression after extraction. One of the limitations of this pilot study is the small sample size. Further validation of these results must be done with a larger sample size in order to provide clinical guidance to dental practitioners.

Advisors/Committee Members: Prakasam, Sivaraman, Blanchard, Steven B., Parks, Edwin T. (Edwin Thomas), 1955-, Ghoneima, Ahmed, John, Vanchit (Vanchit Kurien), 1965-.

Subjects/Keywords: Ridge Compression; Socket Compression; Extraction; Compression; Post-operative; Tooth Extraction – adverse effects; Tooth Socket – surgery; Alveolar Bone Loss – prevention & control; Alveolar Process; Wound Healing

…post-extraction �� ...31 Figure 1 Comparison of subjects divided by compression… …and height when compared to sites without post-extraction ridge compression. Additionally… …determine if post-extraction socket compression negatively affected residual ridge dimensions when… …such technique is post-extraction socket or ridge compression, which is usually performed per… …without post-extraction compression. The soft tissue healing rate of compressed sites will be…

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

APA (6^th Edition):

Bennett, Duane Everett, II, 1. (2013). Ridge Dimensional Changes: A Comparative Study of Socket Compression After Dental Extraction with No Compression. (Thesis). IUPUI. Retrieved from http://hdl.handle.net/1805/3722

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):

Bennett, Duane Everett, II, 1984-. “Ridge Dimensional Changes: A Comparative Study of Socket Compression After Dental Extraction with No Compression.” 2013. Thesis, IUPUI. Accessed April 11, 2021. http://hdl.handle.net/1805/3722.

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

MLA Handbook (7^th Edition):

Bennett, Duane Everett, II, 1984-. “Ridge Dimensional Changes: A Comparative Study of Socket Compression After Dental Extraction with No Compression.” 2013. Web. 11 Apr 2021.

Vancouver:

Bennett, Duane Everett, II 1. Ridge Dimensional Changes: A Comparative Study of Socket Compression After Dental Extraction with No Compression. [Internet] [Thesis]. IUPUI; 2013. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1805/3722.

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

Council of Science Editors:

Bennett, Duane Everett, II 1. Ridge Dimensional Changes: A Comparative Study of Socket Compression After Dental Extraction with No Compression. [Thesis]. IUPUI; 2013. Available from: http://hdl.handle.net/1805/3722

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

Université de Bordeaux I

17. Dubrouil, Antoine. Post compression d'impulsions intenses ultra-brèves et mise en forme spatiale pour la génération d'impulsions attosecondes intenses : Post compression of high energy ultra-short pulses and spatial shaping of intense laser beams for generation of intense attosecond pulses.

Degree: Docteur es, Lasers, matière et nanosciences, 2011, Université de Bordeaux I

URL: http://www.theses.fr/2011BOR14343

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La génération d'harmoniques d'ordre élevé en milieu gazeux est un phénomène habituellement décrit par un modèle à trois étapes : sous l'effet d'un champ laser… (more)

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La génération d'harmoniques d'ordre élevé en milieu gazeux est un phénomène habituellement décrit par un modèle à trois étapes : sous l'effet d'un champ laser intense, un atome (ou une molécule) est ionisé par effet tunnel. L'électron éjecté est accéléré dans le champ laser, puis il se recombine sur son ion parent en émettant un photon XUV. Ce rayonnement XUV, émis sous la forme d'impulsions attosecondes (1 as = 10-18 s), est un outil idéal pour sonder la structure électronique des atomes ou des molécules, avec une résolution temporelle de l'ordre de l'attoseconde. Néanmoins, l'intensité de ce rayonnement n'est en général pas suffisante pour induire des effets non-linéaires (transitions à deux photons).Au cours des travaux réalisés pendant cette thèse, nous avons développé une source harmonique capable de produire un rayonnement XUV intense qui doit permettre d'accéder à la physique non-linéaire dans cette gamme de longueur d'onde. Pour parvenir à ces résultats, un travail important sur les impulsions infrarouges génératrices a été nécessaire, aussi bien dans le domaine spatial que dans le domaine temporel. Une technique de mise en forme spatiale de faisceaux laser intenses a donc été développée, ainsi qu'une technique de post compression adaptée aux impulsions laser intenses. Ce travail de thèse se divise donc en trois étapes : - Le développement de la source harmonique haute énergie et des diagnostics associés. Cette source est basée sur l'utilisation d'une chaîne laser Titane-Saphir qui délivre des impulsions de 150 mJ pour des durées de 40 fs à une cadence de 10 Hz. De bonnes conditions d'optimisation ont été obtenues, donnant lieu à des impulsions XUV dont l'énergie est de l'ordre du µJ lors de la génération dans l'argon.- Le développement d'une technique de mise en forme spatiale adaptée aux faisceaux laser intenses et à la génération d'harmoniques. Le dispositif est basé sur une optique en réflexion et sur les interférences à deux faisceaux. Il permet de produire, dans la région focale, des faisceaux dont le profil d'intensité est radialement constant (faisceaux flat top) et ainsi d'apporter un contrôle supplémentaire sur la génération d'harmoniques d'ordre élevé.- Le développement d'une technique de post compression en propagation guidée basée sur l'élargissement spectral induit par ionisation. Cette technique est adaptée pour des impulsions intenses (3.5 TW) et permet de produire des impulsions de puissance crête supérieure au Térawatt dans le domaine sub-10 fs. Cette technique fournit donc une source unique pour la génération d'harmoniques d'ordre élevé.Ces deux approches ont été testées et validées pour la génération d'harmoniques d'ordre élevé, et les résultats obtenus ouvrent d'intéressantes perspectives telles que la génération d'impulsions attosecondes isolées de haute énergie (> 100 nJ).

The generation of high order harmonics in a gaseous medium is a phenomenon conveniently described by a three steps model : subject to a strong laser field irradiation, an atom (or molecule) can undergo a…

Advisors/Committee Members: Constant, Eric (thesis director).

Subjects/Keywords: Interaction laser matière; Optique non-linéaire; Génération d'harmoniques d'ordre élevé; Impulsion attoseconde; Physique non-linéaire XUV; Faisceau laser intense; Mise en forme spatiale; Post compression; Propagation guidée; Élargissement spectral par ionisation; Impulsion intense ultra-brève; Laser-matter interaction; Non-linear optics; High order harmonics generation; Attosecond pulse; XUV non-linear physics; Intense laser beam; Spatial shaping; Post compression; Ionization induced spectral broadening; Intense ultra-short pulse

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

APA (6^th Edition):

Dubrouil, A. (2011). Post compression d'impulsions intenses ultra-brèves et mise en forme spatiale pour la génération d'impulsions attosecondes intenses : Post compression of high energy ultra-short pulses and spatial shaping of intense laser beams for generation of intense attosecond pulses. (Doctoral Dissertation). Université de Bordeaux I. Retrieved from http://www.theses.fr/2011BOR14343

Chicago Manual of Style (16^th Edition):

Dubrouil, Antoine. “Post compression d'impulsions intenses ultra-brèves et mise en forme spatiale pour la génération d'impulsions attosecondes intenses : Post compression of high energy ultra-short pulses and spatial shaping of intense laser beams for generation of intense attosecond pulses.” 2011. Doctoral Dissertation, Université de Bordeaux I. Accessed April 11, 2021. http://www.theses.fr/2011BOR14343.

MLA Handbook (7^th Edition):

Dubrouil, Antoine. “Post compression d'impulsions intenses ultra-brèves et mise en forme spatiale pour la génération d'impulsions attosecondes intenses : Post compression of high energy ultra-short pulses and spatial shaping of intense laser beams for generation of intense attosecond pulses.” 2011. Web. 11 Apr 2021.

Vancouver:

Dubrouil A. Post compression d'impulsions intenses ultra-brèves et mise en forme spatiale pour la génération d'impulsions attosecondes intenses : Post compression of high energy ultra-short pulses and spatial shaping of intense laser beams for generation of intense attosecond pulses. [Internet] [Doctoral dissertation]. Université de Bordeaux I; 2011. [cited 2021 Apr 11]. Available from: http://www.theses.fr/2011BOR14343.

Council of Science Editors:

Dubrouil A. Post compression d'impulsions intenses ultra-brèves et mise en forme spatiale pour la génération d'impulsions attosecondes intenses : Post compression of high energy ultra-short pulses and spatial shaping of intense laser beams for generation of intense attosecond pulses. [Doctoral Dissertation]. Université de Bordeaux I; 2011. Available from: http://www.theses.fr/2011BOR14343

Université de Bordeaux I

18. Fourcade Dutin, Coralie. Réduction de la durée d’impulsions laser par des techniques extra et intra-cavité : post-compression d’impulsions femtosecondes énergétiques et modulation spectrale des pertes dans un pré-amplificateur Ti˸saphir : Reduction of the laser pulse duration with extra and intra cavity techniques : Energetic femtosecond pulses post-compression and spectral modulation of losses in the Ti˸sapphire preamplifier.

Degree: Docteur es, Lasers, matière et nanosciences, 2011, Université de Bordeaux I

URL: http://www.theses.fr/2011BOR14298

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La course vers les impulsions ultra-courtes et énergétiques est en plein essor avec le développement de nombreuses applications. Dans ce manuscrit, plusieurs méthodes de réduction… (more)

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La course vers les impulsions ultra-courtes et énergétiques est en plein essor avec le développement de nombreuses applications. Dans ce manuscrit, plusieurs méthodes de réduction de la durée d'impulsion énergétique sont étudiées. La mise en oeuvre d’un système de post-compression basé sur le principe de SPM-NER dans une lame de silice a tout d'abord permis de produire, à partir d'impulsions de 50 fs, des impulsions de 16 fs-5mJ. Dans une seconde partie, nous proposons une nouvelle méthode de post-compression efficace basée sur l'ionisation d'un gaz rare dans un capillaire creux. Cette technique a permis d'obtenir à la fois des impulsions ultra-courtes et des énergies importantes (11 fs-13 mJ). Les résultats d'une modélisation réalisée au CEA/SPAM, en bon accord avec les résultats expérimentaux, ont permis d'approfondir la compréhension des divers mécanismes mis en jeu. Afin de produire des impulsions encore plus courtes, il est nécessaire de travailler directement dans les chaînes laser, en amont du système de post-compression. Le rétrécissement spectral par le gain dans leTi:saphir des chaînes laser, limite en général les durées des impulsions à 30 fs. Ce phénomène, étudié lors de cette thèse, a été compensé grâce à une modulation de perte spectrale (filtre) dans le pré-amplificateur (cavité régénérative), localisée au maximum de la courbe de gain. Des impulsions de l’ordre de 20 fs ont été obtenues. Ces études ont été complétées par une modélisation de l'amplification des impulsions qui s'est avérée en très bon accord avec les mesures expérimentales. La possibilité de combiner ces procédés permettra, àcourt terme, la production d'impulsions laser sub-10 fs énergétiques (~10 mJ) pour générer des impulsions XUV attosecondes isolées.

High energy ultrashort pulses are highly desirable for many applications. In thismanuscript, we described several methods for pulse duration reduction at high energy. A postcompressionsystem, using SPM-NER in a fused silica plate, has firstly provided 16 fs-5mJpulses, from 50 fs pulses. In a second part, we present a new efficient post compressiontechnique, achieved through ionization of gas in a capillary. With this technique, ultrashortand high energy pulses have been reached (11 fs-13 mJ). Results from modeling done atCEA/SPAM, in good agreement with the experimental ones, have been used to understanddeeply all the involved mechanisms. In order to get even shorter pulses, it is incontrovertibleto work on the laser chain, in front of the post-compression systems. In general, due tospectral gain narrowing in Ti:Saphir laser chain, the pulse duration is limited to 30 fs. Thiseffect, investigated in this thesis, has been compensated by modulating the spectral losses(filter) in the pre-amplifier (regenerative cavity), localized at the gain curve maximum. Pulseduration in the order of 20 fs has been obtained. This study has been completed with a pulseamplification model that shows very good agreement with the experimental measurements.The possibility to combine these processes should…

Advisors/Committee Members: Martin, Patrick (thesis director), Descamps, Dominique (thesis director).

Subjects/Keywords: Impulsions femtosecondes; Optique non-linéaire; Post-compression d'impulsion femtosecondes; Ionisation en champs fort de gaz; Automodulation de phase; Rotation nonlinéaire de polarisation; Rétrécissement spectral par le gain dans le cristal de Ti:saphir; Femtosecond pulses; Non linear optic; Femtosecond pulse post compression; Gas ionisation in a strong field; Self phase modulation; Non-linear elliptical rotation; Spectral gain narrowing in Ti:Saphir crystal; Non-linear elliptical rotation

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

APA (6^th Edition):

Fourcade Dutin, C. (2011). Réduction de la durée d’impulsions laser par des techniques extra et intra-cavité : post-compression d’impulsions femtosecondes énergétiques et modulation spectrale des pertes dans un pré-amplificateur Ti˸saphir : Reduction of the laser pulse duration with extra and intra cavity techniques : Energetic femtosecond pulses post-compression and spectral modulation of losses in the Ti˸sapphire preamplifier. (Doctoral Dissertation). Université de Bordeaux I. Retrieved from http://www.theses.fr/2011BOR14298

Chicago Manual of Style (16^th Edition):

Fourcade Dutin, Coralie. “Réduction de la durée d’impulsions laser par des techniques extra et intra-cavité : post-compression d’impulsions femtosecondes énergétiques et modulation spectrale des pertes dans un pré-amplificateur Ti˸saphir : Reduction of the laser pulse duration with extra and intra cavity techniques : Energetic femtosecond pulses post-compression and spectral modulation of losses in the Ti˸sapphire preamplifier.” 2011. Doctoral Dissertation, Université de Bordeaux I. Accessed April 11, 2021. http://www.theses.fr/2011BOR14298.

MLA Handbook (7^th Edition):

Fourcade Dutin, Coralie. “Réduction de la durée d’impulsions laser par des techniques extra et intra-cavité : post-compression d’impulsions femtosecondes énergétiques et modulation spectrale des pertes dans un pré-amplificateur Ti˸saphir : Reduction of the laser pulse duration with extra and intra cavity techniques : Energetic femtosecond pulses post-compression and spectral modulation of losses in the Ti˸sapphire preamplifier.” 2011. Web. 11 Apr 2021.

Vancouver:

Fourcade Dutin C. Réduction de la durée d’impulsions laser par des techniques extra et intra-cavité : post-compression d’impulsions femtosecondes énergétiques et modulation spectrale des pertes dans un pré-amplificateur Ti˸saphir : Reduction of the laser pulse duration with extra and intra cavity techniques : Energetic femtosecond pulses post-compression and spectral modulation of losses in the Ti˸sapphire preamplifier. [Internet] [Doctoral dissertation]. Université de Bordeaux I; 2011. [cited 2021 Apr 11]. Available from: http://www.theses.fr/2011BOR14298.

Council of Science Editors:

Fourcade Dutin C. Réduction de la durée d’impulsions laser par des techniques extra et intra-cavité : post-compression d’impulsions femtosecondes énergétiques et modulation spectrale des pertes dans un pré-amplificateur Ti˸saphir : Reduction of the laser pulse duration with extra and intra cavity techniques : Energetic femtosecond pulses post-compression and spectral modulation of losses in the Ti˸sapphire preamplifier. [Doctoral Dissertation]. Université de Bordeaux I; 2011. Available from: http://www.theses.fr/2011BOR14298

19. Lawler, Benjamin John. A Methodology for Assessing Thermal Stratification in an HCCI Engine and Understanding the Impact of Engine Design and Operating Conditions.

Degree: PhD, Mechanical Engineering, 2013, University of Michigan

URL: http://hdl.handle.net/2027.42/102425

► HCCI is a promising advanced engine concept with the potential to pair high thermal efficiencies with ultra-low emissions. However, HCCI has so far been demonstrated… (more)

▼ HCCI is a promising advanced engine concept with the potential to pair high thermal efficiencies with ultra-low emissions. However, HCCI has so far been demonstrated only over a narrow operating range due to a lack of control over HCCI burn rates. While there is an emerging consensus about the critical role of thermal stratification on HCCI burn rates, there was a gap related to availability of a method to rapidly assess the impact of engine design or operating conditions on thermal stratification in a practical HCCI engine. The objectives of this research are to develop a novel post-processing technique for studying thermal stratification in a fired, metal HCCI engine, and use the proposed technique to understand the impact of operating conditions on the in-cylinder unburned temperature distribution. The technique is called the Thermal Stratification Analysis (TSA) and it uses the autoignition integral coupled to the mass fraction burned curve to determine a distribution of mass and temperature in the cylinder prior to combustion. The technique is then validated by comparing the TSA results to predictions from CFD simulations and experimentally measured unburned temperature distributions in an optical engine. A large amount of data was collected and processed with the TSA to determine the effects of engine design and operating conditions on the in-cylinder unburned temperature distribution and HCCI burn rates. The results show that the thermal width increases with a higher internal residual gas fraction, increasing intake temperature, advancing combustion phasing, increasing the maximum TDC temperature, and increasing the in-cylinder swirl. Finally, an innovative method for active control of the thermal stratification and HCCI burn rates with a glow plug is proposed. The results show that the glow plug is able to control combustion phasing and, more importantly, broaden the temperature distribution and lengthen the burn duration a considerable amount. The glow plug improves some of the emissions characteristics slightly and the combustion efficiency as well. The main drawbacks of using a glow plug in HCCI are the efficiency penalty associated with the energy consumed by the glow plug and the observed increase in the cycle-to-cycle variations. Advisors/Committee Members: Atreya, Arvind (committee member), Filipi, Zoran S. (committee member), Driscoll, James F. (committee member), Lavoie, George A. (committee member), Sick, Volker (committee member), Borgnakke, Claus (committee member).

Subjects/Keywords: Homogeneous Charge Compression Ignition; Heat Release Analysis; Thermal Stratification; Post-Processing; Mechanical Engineering; Engineering

…167 7.1 Compression Ratio… …compression and expansion processes......................................62 Figure 2.12 − Effect of… …165 Figure 7.1 − Mass fraction burned curves for the compression ratio comparison… …169 Figure 7.2 − Bulk temperatures for the compression ratio comparison… …170 Figure 7.3 − Unburned temperature distributions for the compression ratio comparison…

10 more images…

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

APA (6^th Edition):

Lawler, B. J. (2013). A Methodology for Assessing Thermal Stratification in an HCCI Engine and Understanding the Impact of Engine Design and Operating Conditions. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/102425

Chicago Manual of Style (16^th Edition):

Lawler, Benjamin John. “A Methodology for Assessing Thermal Stratification in an HCCI Engine and Understanding the Impact of Engine Design and Operating Conditions.” 2013. Doctoral Dissertation, University of Michigan. Accessed April 11, 2021. http://hdl.handle.net/2027.42/102425.

MLA Handbook (7^th Edition):

Lawler, Benjamin John. “A Methodology for Assessing Thermal Stratification in an HCCI Engine and Understanding the Impact of Engine Design and Operating Conditions.” 2013. Web. 11 Apr 2021.

Vancouver:

Lawler BJ. A Methodology for Assessing Thermal Stratification in an HCCI Engine and Understanding the Impact of Engine Design and Operating Conditions. [Internet] [Doctoral dissertation]. University of Michigan; 2013. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/2027.42/102425.

Council of Science Editors:

Lawler BJ. A Methodology for Assessing Thermal Stratification in an HCCI Engine and Understanding the Impact of Engine Design and Operating Conditions. [Doctoral Dissertation]. University of Michigan; 2013. Available from: http://hdl.handle.net/2027.42/102425

Brigham Young University

20. Blanc, Trevor Jon. Analysis and Compression of Large CFD Data Sets Using Proper Orthogonal Decomposition.

Degree: MS, 2014, Brigham Young University

URL: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=6302&context=etd

► Efficient analysis and storage of data is an integral but often challenging task when working with computation fluid dynamics mainly due to the amount of… (more)

▼ Efficient analysis and storage of data is an integral but often challenging task when working with computation fluid dynamics mainly due to the amount of data it can output. Methods centered around the proper orthogonal decomposition were used to analyze, compress, and model various simulation cases. Two different high-fidelity, time-accurate turbomachinery simulations were investigated to show various applications of the analysis techniques. The first turbomachinery example was used to illustrate the extraction of turbulent coherent structures such as traversing shocks, vortex shedding, and wake variation from deswirler and rotor blade passages. Using only the most dominant modes, flow fields were reconstructed and analyzed for error. The reconstructions reproduced the general dynamics within the flow well, but failed to fully resolve shock fronts and smaller vortices. By decomposing the domain into smaller, independent pieces, reconstruction error was reduced by up to 63 percent. A new method of data compression that combined an image compression algorithm and the proper orthogonal decomposition was used to store the reconstructions of the flow field, increasing data compression ratios by a factor of 40.The second turbomachinery simulation studied was a three-stage fan with inlet total pressure distortion. Both the snapshot and repeating geometry methods were used to characterize structures of static pressure fluctuation within the blade passages of the third rotor blade row. Modal coefficients filtered by frequencies relating to the inlet distortion pattern were used to produce reconstructions of the pressure field solely dependent on the inlet boundary condition. A hybrid proper orthogonal decomposition method was proposed to limit burdens on computational resources while providing high temporal resolution analysis.Parametric reduced order models were created from large databases of transient and steady conjugate heat transfer and airfoil simulations. Performance of the models were found to depend heavily on the range of the parameters varied as well as the number of simulations used to traverse that range. The heat transfer models gave excellent predictions for temperature profiles in heated solids for ambitious parameter ranges. Model development for the airfoil case showed that accuracy was highly dependent on modal truncation. The flow fields were predicted very well, especially outside the boundary layer region of the flow.

Subjects/Keywords: proper orthogonal decomposition; reduced order models; reduced order reconstruction; data compression; computational fluid dynamics; post-processing; domain decomposition; computational fluid dynamics; coherent structures; turbomachinery; pressure distortion; conjugate heat transfer; Mechanical Engineering

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

APA (6^th Edition):

Blanc, T. J. (2014). Analysis and Compression of Large CFD Data Sets Using Proper Orthogonal Decomposition. (Masters Thesis). Brigham Young University. Retrieved from https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=6302&context=etd

Chicago Manual of Style (16^th Edition):

Blanc, Trevor Jon. “Analysis and Compression of Large CFD Data Sets Using Proper Orthogonal Decomposition.” 2014. Masters Thesis, Brigham Young University. Accessed April 11, 2021. https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=6302&context=etd.

MLA Handbook (7^th Edition):

Blanc, Trevor Jon. “Analysis and Compression of Large CFD Data Sets Using Proper Orthogonal Decomposition.” 2014. Web. 11 Apr 2021.

Vancouver:

Blanc TJ. Analysis and Compression of Large CFD Data Sets Using Proper Orthogonal Decomposition. [Internet] [Masters thesis]. Brigham Young University; 2014. [cited 2021 Apr 11]. Available from: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=6302&context=etd.

Council of Science Editors:

Blanc TJ. Analysis and Compression of Large CFD Data Sets Using Proper Orthogonal Decomposition. [Masters Thesis]. Brigham Young University; 2014. Available from: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=6302&context=etd

21. Zhang, Tengteng. High Quality Test Generation Targeting Power Supply Noise.

Degree: PhD, Computer Engineering, 2015, Texas A&M University

URL: http://hdl.handle.net/1969.1/156186

► Delay test is an essential structural manufacturing test used to determine the maximal frequency at which a chip can run without incurring any functional failures.… (more)

▼ Delay test is an essential structural manufacturing test used to determine the maximal frequency at which a chip can run without incurring any functional failures. The central unsolved challenge is achieving high delay correlation with the functional test, which is dominated by power supply noise (PSN). Differences in PSN between functional and structural tests can lead to differences in chip operating frequencies of 30% or more. Pseudo functional test (PFT), based on a multiple-cycle clocking scheme, has better PSN correlation with functional test compared with traditional two-cycle at-speed test. However, PFT is vulnerable to under-testing when applied to delay test. This work aims to generate high quality PFT patterns, achieving high PSN correlation with functional test. First, a simulation-based don’t-care filling algorithm, Bit-Flip, is proposed to improve the PSN for PFT. It relies on randomly flipping a group of bits in the test pattern to explore the search space and find patterns that stress the circuits with the worst-case, but close to functional PSN. Experimental results on un-compacted patterns show Bit-Flip is able to improve PSN as much as 38.7% compared with the best random fill. Second, techniques are developed to improve the efficiency of Bit-Flip. A set of partial patterns, which sensitize transitions on critical cells, are pre-computed and later used to guide the selection of bits to flip. Combining random and deterministic flipping, we achieve similar PSN control as Bit-Flip but with much less simulation time. Third, we address the problem of automatic test pattern generation for extracting circuit timing sensitivity to power supply noise during post-silicon validation. A layout-aware path selection algorithm selects long paths to fully span the power delivery network. The selected patterns are intelligently filled to bring the PSN to a desired level. These patterns can be used to understand timing sensitivity in post-silicon validation by repeatedly applying the path delay test while sweeping the PSN experienced by the path from low to high. Finally, the impacts of compression on power supply noise control are studied. Illinois Scan and embedded deterministic test (EDT) patterns are generated. Then Bit-Flip is extended to incorporate the compression constraints and applied to compressible patterns. The experimental results show that EDT lowers the maximal PSN by 24.15% and Illinois Scan lowers it by 2.77% on un-compacted patterns. Advisors/Committee Members: Walker, Duncan M. (advisor), Shi, Weiping (committee member), Liu, Jyh-Charn (committee member), Mahapatra, Rabi (committee member).

Subjects/Keywords: Path Delay Test; Power Supply Noise; Post Silicon Validation; Test Compression

…51 Fig. 24 Pattern generation and post-silicon validation… …58 Fig. 27 Post-ATPG processing flow… …67 Table 12 PSN post processing results w/ filtering… …71 Table 13 PSN post processing results w/o filtering… …Test pattern compaction and compression are two popular techniques developed to reduce the…

9 more images…

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

APA (6^th Edition):

Zhang, T. (2015). High Quality Test Generation Targeting Power Supply Noise. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/156186

Chicago Manual of Style (16^th Edition):

Zhang, Tengteng. “High Quality Test Generation Targeting Power Supply Noise.” 2015. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/156186.

MLA Handbook (7^th Edition):

Zhang, Tengteng. “High Quality Test Generation Targeting Power Supply Noise.” 2015. Web. 11 Apr 2021.

Vancouver:

Zhang T. High Quality Test Generation Targeting Power Supply Noise. [Internet] [Doctoral dissertation]. Texas A&M University; 2015. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/156186.

Council of Science Editors:

Zhang T. High Quality Test Generation Targeting Power Supply Noise. [Doctoral Dissertation]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/156186

22. Schiavon, Ana Paula. Post-stack seismic data compression with multidimensional deep autoencoders.

Degree: 2020, Universidade Federal de Juiz de Fora (UFJF); Programa de Pós-graduação em Ciência da Computação; UFJF; Brasil; ICE – Instituto de Ciências Exatas

URL: https://repositorio.ufjf.br/jspui/handle/ufjf/11927

►

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Dados sísmicos s~ao mapeamentos da subsuperfície terrestre que têm como objetivo representar as características geofísicas… (more)

▼

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Dados sísmicos s~ao mapeamentos da subsuperfície terrestre que têm como objetivo representar as características geofísicas da região onde eles foram obtidos de forma que possam ser interpretados. Esses dados podem ocupar centenas de Gigabytes de armazenamento, motivando sua compressão. Neste trabalho o problema de compressão de dados sísmicos tridimensionais pós-pilha é abordado usando modelos baseados em autocodificadores profundos. O autocodificador profundo é uma rede neural que permite representar a maior parte da informação contida em um dado sísmico com um custo menor que sua representação original. De acordo com nosso conhecimento, este é o primeiro trabalho a lidar com compressão de dados sísmicos utilizando aprendizado profundo. Dessa forma, através de aproximações sucessivas, são propostos quatro métodos de compressão de dados tridimensionais pós-pilha: dois baseados em compressão bidimensional, chamados Método de Compressão 2D de Dado Sísmico (2DSC) e Método de Compressão 2D de Dado Sísmico usando Multi-resolução (2DSC-MR), e dois baseados em compressão tridimensional, chamados Método de Compressão 3D de Dado Sísmico (3DSC) e Método de Compressão 3D de Dado Sísmico usando Quantização Vetorial (3DSC-VQ). O método 2DSC é o nosso método de compressão do dado sísmico mais simples, onde o volume é comprimido a partir de suas seções bidimensionais. O método 2DSC-MR estende o método anterior introduzindo a compressão do dado em múltiplas resoluções. O método 3DSC estende o método 2DSC permitindo a compressão do dado sísmico em sua forma volumétrica, considerando a similaridade entre seções para representar um volume inteiro com o custo de apenas uma seção. O método 3DSC-VQ utiliza quantização vetorial para relaxar a etapa de codificação do método anterior, dando maior liberdade à rede para extrair informação dos volumes sísmicos. O objetivo deste trabalho é comprimir o dado sísmico a baixas taxas de bits e com alta qualidade de reconstrução em termos de PSNR e bits-por-voxel (bpv). Experimentos mostram que os quatro métodos podem comprimir o dado sísmico fornecendo valores de PSNR acima de 40 dB a taxas de bits abaixo de 1.0 bpv.

Seismic data are surveys from the Earth's subsurface with the goal of representing the geophysical characteristics from the region where they were obtained in order to be interpreted. These data can occupy hundreds of Gigabytes of storage, motivating their compression. In this work, we approach the problem of three-dimensional post-stack seismic data using models based on deep autoencoders. The deep autoencoder is a neural network that allows representing most of the information of a seismic data with a lower cost in comparison to its original representation. To the best of our knowledge, this is the rst work to deal with seismic compression using deep learning. Four compression methods for post-stack data are proposed: two based on a bi-dimensional compression, named 2D-based…

Advisors/Committee Members: Vieira, Marcelo Bernardes, Villela, Saulo Moraes, Pedrini, Hélio.

Subjects/Keywords: CNPQ::CIENCIAS EXATAS E DA TERRA; Compressão de sado sísmico; Aprendizado profundo; Autocodificados; Dado sísmico tridimensional pós-pilha; Processamento de imagem geofísica; Seismic data compression; Deep learning; Autoencoder; 3D post-stack seismic data; Geophysical image processing

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

APA (6^th Edition):

Schiavon, A. P. (2020). Post-stack seismic data compression with multidimensional deep autoencoders. (Masters Thesis). Universidade Federal de Juiz de Fora (UFJF); Programa de Pós-graduação em Ciência da Computação; UFJF; Brasil; ICE – Instituto de Ciências Exatas. Retrieved from https://repositorio.ufjf.br/jspui/handle/ufjf/11927

Chicago Manual of Style (16^th Edition):

Schiavon, Ana Paula. “Post-stack seismic data compression with multidimensional deep autoencoders.” 2020. Masters Thesis, Universidade Federal de Juiz de Fora (UFJF); Programa de Pós-graduação em Ciência da Computação; UFJF; Brasil; ICE – Instituto de Ciências Exatas. Accessed April 11, 2021. https://repositorio.ufjf.br/jspui/handle/ufjf/11927.

MLA Handbook (7^th Edition):

Schiavon, Ana Paula. “Post-stack seismic data compression with multidimensional deep autoencoders.” 2020. Web. 11 Apr 2021.

Vancouver:

Schiavon AP. Post-stack seismic data compression with multidimensional deep autoencoders. [Internet] [Masters thesis]. Universidade Federal de Juiz de Fora (UFJF); Programa de Pós-graduação em Ciência da Computação; UFJF; Brasil; ICE – Instituto de Ciências Exatas; 2020. [cited 2021 Apr 11]. Available from: https://repositorio.ufjf.br/jspui/handle/ufjf/11927.

Council of Science Editors:

Schiavon AP. Post-stack seismic data compression with multidimensional deep autoencoders. [Masters Thesis]. Universidade Federal de Juiz de Fora (UFJF); Programa de Pós-graduação em Ciência da Computação; UFJF; Brasil; ICE – Instituto de Ciências Exatas; 2020. Available from: https://repositorio.ufjf.br/jspui/handle/ufjf/11927

University of Canterbury

23. Maekawa, K. Post-peak cyclic response analysis and energy dissipation capacity of RC columns.

Degree: Civil and Natural Resources Engineering, 2001, University of Canterbury

URL: http://hdl.handle.net/10092/4447

► The main aim of this study is to investigate the factors governing the post-peak cyclic response of laterally loaded reinforced concrete cantilever columns. A series… (more)

Subjects/Keywords: axial compression; buckling; cover spalling; energy dissipation; post-peak softening; Fields of Research::40 - Engineering::4005 - Civil engineering::400510 - Structural engineering

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

APA (6^th Edition):

Maekawa, K. (2001). Post-peak cyclic response analysis and energy dissipation capacity of RC columns. (Thesis). University of Canterbury. Retrieved from http://hdl.handle.net/10092/4447

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):

Maekawa, K. “Post-peak cyclic response analysis and energy dissipation capacity of RC columns.” 2001. Thesis, University of Canterbury. Accessed April 11, 2021. http://hdl.handle.net/10092/4447.

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

MLA Handbook (7^th Edition):

Maekawa, K. “Post-peak cyclic response analysis and energy dissipation capacity of RC columns.” 2001. Web. 11 Apr 2021.

Vancouver:

Maekawa K. Post-peak cyclic response analysis and energy dissipation capacity of RC columns. [Internet] [Thesis]. University of Canterbury; 2001. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/10092/4447.

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

Council of Science Editors:

Maekawa K. Post-peak cyclic response analysis and energy dissipation capacity of RC columns. [Thesis]. University of Canterbury; 2001. Available from: http://hdl.handle.net/10092/4447

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

University of New South Wales

24. Leung, Raymond. Scalable video compression with optimized visual performance and random accessibility.

Degree: Electrical Engineering & Telecommunications, 2006, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/24192 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:935/SOURCE01?view=true

► This thesis is concerned with maximizing the coding efficiency, random accessibility and visual performance of scalable compressed video. The unifying theme behind this work is… (more)

▼ This thesis is concerned with maximizing the coding efficiency, random accessibility and visual performance of scalable compressed video. The unifying theme behind this work is the use of finely embedded localized coding structures, which govern the extent to which these goals may be jointly achieved. The first part focuses on scalable volumetric image compression. We investigate 3D transform and coding techniques which exploit inter-slice statistical redundancies without compromising slice accessibility. Our study shows that the motion-compensated temporal discrete wavelet transform (MC-TDWT) practically achieves an upper bound to the compression efficiency of slice transforms. From a video coding perspective, we find that most of the coding gain is attributed to offsetting the learning penalty in adaptive arithmetic coding through 3D code-block extension, rather than inter-frame context modelling.The second aspect of this thesis examines random accessibility. Accessibility refers to the ease with which a region of interest is accessed (subband samples needed for reconstruction are retrieved) from a compressed video bitstream, subject to spatiotemporal code-block constraints. We investigate the fundamental implications of motion compensation for random access efficiency and the compression performance of scalable interactive video. We demonstrate that inclusion of motion compensation operators within the lifting steps of a temporal subband transform incurs a random access penalty which depends on the characteristics of the motion field.The final aspect of this thesis aims to minimize the perceptual impact of visible distortion in scalable reconstructed video. We present a visual optimization strategy based on distortion scaling which raises the distortion-length slope of perceptually significant samples. This alters the codestream embedding order during post-compression rate-distortion optimization, thus allowing visually sensitive sites to be encoded with higher fidelity at a given bit-rate.For visual sensitivity analysis, we propose a contrast perception model that incorporates an adaptive masking slope. This versatile feature provides a context which models perceptual significance. It enables scene structures that otherwise suffer significant degradation to be preserved at lower bit-rates. The novelty in our approach derives from a set of "perceptual mappings" which account for quantization noise shaping effects induced by motion-compensated temporal synthesis. The proposed technique reduces wavelet compression artefacts and improves the perceptual quality of video.

Subjects/Keywords: scalable video compression; visual optimization; perceptual quality; perceived distortion; region of interest; random access efficiency; wavelet artefacts; temporal subband synthesis; perceptual mapping; localized embedded coding structures; EBCOT; post-compression rate-distortion optimization (PCRD-opt); 3-D context modelling; coding gain

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

APA (6^th Edition):

Leung, R. (2006). Scalable video compression with optimized visual performance and random accessibility. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/24192 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:935/SOURCE01?view=true

Chicago Manual of Style (16^th Edition):

Leung, Raymond. “Scalable video compression with optimized visual performance and random accessibility.” 2006. Doctoral Dissertation, University of New South Wales. Accessed April 11, 2021. http://handle.unsw.edu.au/1959.4/24192 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:935/SOURCE01?view=true.

MLA Handbook (7^th Edition):

Leung, Raymond. “Scalable video compression with optimized visual performance and random accessibility.” 2006. Web. 11 Apr 2021.

Vancouver:

Leung R. Scalable video compression with optimized visual performance and random accessibility. [Internet] [Doctoral dissertation]. University of New South Wales; 2006. [cited 2021 Apr 11]. Available from: http://handle.unsw.edu.au/1959.4/24192 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:935/SOURCE01?view=true.

Council of Science Editors:

Leung R. Scalable video compression with optimized visual performance and random accessibility. [Doctoral Dissertation]. University of New South Wales; 2006. Available from: http://handle.unsw.edu.au/1959.4/24192 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:935/SOURCE01?view=true

University of Canterbury

25. Maekawa, Koichi. Factors Governing the Post-Peak Hysteresis Loops of Reinforced Concrete Columns.

Degree: Civil and Natural Resources Engineering, 2002, University of Canterbury

URL: http://hdl.handle.net/10092/4390

► The main aim of this study is to investigate the factors governing the post-peak cyclic response of laterally loaded reinforced concrete cantilever columns. A series… (more)

Subjects/Keywords: axial compression; buckling; cover spalling; energy dissipation; post-peak softening; Field of Research::09 - Engineering::0905 - Civil Engineering; Fields of Research::40 - Engineering::4005 - Civil engineering::400504 - Construction engineering

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

APA (6^th Edition):

Maekawa, K. (2002). Factors Governing the Post-Peak Hysteresis Loops of Reinforced Concrete Columns. (Thesis). University of Canterbury. Retrieved from http://hdl.handle.net/10092/4390

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):

Maekawa, Koichi. “Factors Governing the Post-Peak Hysteresis Loops of Reinforced Concrete Columns.” 2002. Thesis, University of Canterbury. Accessed April 11, 2021. http://hdl.handle.net/10092/4390.

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

MLA Handbook (7^th Edition):

Maekawa, Koichi. “Factors Governing the Post-Peak Hysteresis Loops of Reinforced Concrete Columns.” 2002. Web. 11 Apr 2021.

Vancouver:

Maekawa K. Factors Governing the Post-Peak Hysteresis Loops of Reinforced Concrete Columns. [Internet] [Thesis]. University of Canterbury; 2002. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/10092/4390.

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

Council of Science Editors:

Maekawa K. Factors Governing the Post-Peak Hysteresis Loops of Reinforced Concrete Columns. [Thesis]. University of Canterbury; 2002. Available from: http://hdl.handle.net/10092/4390

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

University of Canterbury

26. Mander, J.B. Behavior of steel fibre reinforced concrete in compression.

Degree: Civil and Natural Resources Engineering, 2005, University of Canterbury

URL: http://hdl.handle.net/10092/4408

► Standard compression tests are conducted on concrete cylinders made with concrete having different amount of steel fibres to investigate compression behaviour of steel fibre reinforced… (more)

Subjects/Keywords: Steel fibre reinforced concrete (SFRC); plain concrete; fibre content; compression; normalized stress-strain relationship; compressive strength; peak strain; post-peak softening; Fields of Research::40 - Engineering::4005 - Civil engineering::400505 - Construction materials; Fields of Research::40 - Engineering::4005 - Civil engineering::400504 - Construction engineering

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

APA (6^th Edition):

Mander, J. B. (2005). Behavior of steel fibre reinforced concrete in compression. (Thesis). University of Canterbury. Retrieved from http://hdl.handle.net/10092/4408

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):

Mander, J B. “Behavior of steel fibre reinforced concrete in compression.” 2005. Thesis, University of Canterbury. Accessed April 11, 2021. http://hdl.handle.net/10092/4408.

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

MLA Handbook (7^th Edition):

Mander, J B. “Behavior of steel fibre reinforced concrete in compression.” 2005. Web. 11 Apr 2021.

Vancouver:

Mander JB. Behavior of steel fibre reinforced concrete in compression. [Internet] [Thesis]. University of Canterbury; 2005. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/10092/4408.

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

Council of Science Editors:

Mander JB. Behavior of steel fibre reinforced concrete in compression. [Thesis]. University of Canterbury; 2005. Available from: http://hdl.handle.net/10092/4408

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