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McMaster University
1.
Cuevas-Saavedra, Rogelio.
Weighted Density Approximations for Kohn-Sham Density Functional Theory.
Degree: PhD, 2012, McMaster University
URL: http://hdl.handle.net/11375/12082 
► Approximating the exchange-correlation energy in density functional theory (DFT) is a crucial task. As the only missing element in the Kohn-Sham DFT, the search…
(more)
▼ Approximating the exchange-correlation energy in density functional theory (DFT) is a crucial task. As the only missing element in the Kohn-Sham DFT, the search for better exchange-correlation functionals has been an active field of research for fifty years. Many models and approximations are known and they can be summarized in what is known as the Jacob’s ladder. All the functionals in that ladder are local in the sense that they rely on the information of only one electronic coordinate. That is, even though the exchange-correlation hole, the cornerstone in density functional theory, is a two-electron coordinate quantity, one of the coordinates is averaged over in “Jacob’s ladder functionals.” This makes the calculations considerably more efficient. On the other hand, some of the important constraints on the form of the exchange-correlation functional become inaccessible in the one-point forms. The violation of these constraints leads to functionals plagued by systematic errors, leading to qualitatively incorrect descriptions of some chemical and physical processes. In this thesis the idea of a weighted density approximation (WDA) is explored. More specifically, a symmetric and normalized two-point functional is proposed for the exchange-correlation energy functional. The functional is based entirely on the hole for the uniform electron gas. By construction, these functionals fulfill two of the most important constraints: the normalization of the exchange-correlation hole and the uniform electron gas limit. The findings suggest that we should pursue a whole new generation of “new Jacob’s ladder” functionals. A further step was considered. Given the relevance of the long-range behavior of the exchange-correlation hole, a study of the electronic direct correlation function was performed. The idea was to build up the long-range character of the hole as convoluted pieces of the simple and short-ranged direct correlation function. This direct correlation function provides better results, at least for the correlation energy in the spin-polarized uniform electron gas. The advantage of one-point functionals is their computational efficiency. We therefore attempted to develop new methods that mitigate the relative computational inefficiency of two-point functionals. This led to new methods for evaluating the six-dimensional integrals that are inherent to the exchange-correlation energy.
Doctor of Philosophy (PhD)
Advisors/Committee Members: Ayers, Paul W., Chemistry and Chemical Biology.
Subjects/Keywords: Weighted Density Approximation. Density Functional Theory; Other Chemistry; Other Chemistry
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APA (6th Edition):
Cuevas-Saavedra, R. (2012). Weighted Density Approximations for Kohn-Sham Density Functional Theory. (Doctoral Dissertation). McMaster University. Retrieved from http://hdl.handle.net/11375/12082
Chicago Manual of Style (16th Edition):
Cuevas-Saavedra, Rogelio. “Weighted Density Approximations for Kohn-Sham Density Functional Theory.” 2012. Doctoral Dissertation, McMaster University. Accessed April 10, 2021.
http://hdl.handle.net/11375/12082.
MLA Handbook (7th Edition):
Cuevas-Saavedra, Rogelio. “Weighted Density Approximations for Kohn-Sham Density Functional Theory.” 2012. Web. 10 Apr 2021.
Vancouver:
Cuevas-Saavedra R. Weighted Density Approximations for Kohn-Sham Density Functional Theory. [Internet] [Doctoral dissertation]. McMaster University; 2012. [cited 2021 Apr 10].
Available from: http://hdl.handle.net/11375/12082.
Council of Science Editors:
Cuevas-Saavedra R. Weighted Density Approximations for Kohn-Sham Density Functional Theory. [Doctoral Dissertation]. McMaster University; 2012. Available from: http://hdl.handle.net/11375/12082
Universiteit Utrecht
2.
Dobbelaar, M.C.F.
Large area photonic crystal cavities: a local density approach.
Degree: 2014, Universiteit Utrecht
URL: http://dspace.library.uu.nl:8080/handle/1874/301233
► Slowly chirped two-dimensional photonic crystal cavities are promising devices for creating photonic Bose-Einstein condensates. Before experimentally achieving such a condensate, one first has to thoroughly…
(more)
▼ Slowly chirped two-dimensional photonic crystal cavities are promising devices for creating photonic Bose-Einstein condensates. Before experimentally achieving such a condensate, one first has to thoroughly investigate the electromagnetic eigenmodes in such crystals.
However, slowly chirped photonic crystals leading to cavities for light will easily have sizes in the order of tens of micrometers. Therefore simulating the behaviour of light in these crystals is very time consuming. In this thesis we demonstrate a novel and intuitive approach to obtain the envelopes of the electromagnetic modes in these crystals. An enormous advantage of this approach is that it can calculate the energies and the envelopes of these eigenmodes to a high accuracy in a few seconds.
Advisors/Committee Members: Oosten, D. van.
Subjects/Keywords: FDTD simulations; chirped photonic crystals; local density approximation; quantum harmonic oscillator
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APA (6th Edition):
Dobbelaar, M. C. F. (2014). Large area photonic crystal cavities: a local density approach. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/301233
Chicago Manual of Style (16th Edition):
Dobbelaar, M C F. “Large area photonic crystal cavities: a local density approach.” 2014. Masters Thesis, Universiteit Utrecht. Accessed April 10, 2021.
http://dspace.library.uu.nl:8080/handle/1874/301233.
MLA Handbook (7th Edition):
Dobbelaar, M C F. “Large area photonic crystal cavities: a local density approach.” 2014. Web. 10 Apr 2021.
Vancouver:
Dobbelaar MCF. Large area photonic crystal cavities: a local density approach. [Internet] [Masters thesis]. Universiteit Utrecht; 2014. [cited 2021 Apr 10].
Available from: http://dspace.library.uu.nl:8080/handle/1874/301233.
Council of Science Editors:
Dobbelaar MCF. Large area photonic crystal cavities: a local density approach. [Masters Thesis]. Universiteit Utrecht; 2014. Available from: http://dspace.library.uu.nl:8080/handle/1874/301233
McMaster University
3.
Jennings, Byron K.
The Semiclassical Approximation and Strutinsky Smoothing.
Degree: MSc, 1973, McMaster University
URL: http://hdl.handle.net/11375/18011
► An expression for the semiclassical density of states for a particle in a smooth potential well is obtained from the Kirkwood expansion of the…
(more)
▼ An expression for the semiclassical density of states for a particle in a smooth potential well is obtained from the Kirkwood expansion of the partition function. This expression for the semiclassical density of states is then shown to be essentially equivalent to the expression obtained from the Green's function method of Balian and Bloch. The Strutinsky shell correction to the nuclear binding energy is then analytically shown to be equivalent to the shell correction obtained from a consideration of the semiclassical partition function if certain restrictions on the Strutinsky smoothing parameter can be met.
Thesis
Master of Science (MSc)
Advisors/Committee Members: Bhaduri, R. K., Physics.
Subjects/Keywords: semiclassical; approximation; density; Strutinsky; smoothing
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APA (6th Edition):
Jennings, B. K. (1973). The Semiclassical Approximation and Strutinsky Smoothing. (Masters Thesis). McMaster University. Retrieved from http://hdl.handle.net/11375/18011
Chicago Manual of Style (16th Edition):
Jennings, Byron K. “The Semiclassical Approximation and Strutinsky Smoothing.” 1973. Masters Thesis, McMaster University. Accessed April 10, 2021.
http://hdl.handle.net/11375/18011.
MLA Handbook (7th Edition):
Jennings, Byron K. “The Semiclassical Approximation and Strutinsky Smoothing.” 1973. Web. 10 Apr 2021.
Vancouver:
Jennings BK. The Semiclassical Approximation and Strutinsky Smoothing. [Internet] [Masters thesis]. McMaster University; 1973. [cited 2021 Apr 10].
Available from: http://hdl.handle.net/11375/18011.
Council of Science Editors:
Jennings BK. The Semiclassical Approximation and Strutinsky Smoothing. [Masters Thesis]. McMaster University; 1973. Available from: http://hdl.handle.net/11375/18011
Penn State University
4.
Byun, Young-moo.
First-principles Theoretical Studies of Carbon Nanomaterials and New Data Analysis Methods for Catalytic Platinum Microswimmers.
Degree: 2012, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/16249
► This dissertation has two main topics: carbon nanomaterials and platinum microswimmers. First, carbon nanomaterials such as C60, carbon nanotubes, and graphene have extraordinary physical properties…
(more)
▼ This dissertation has two main topics: carbon nanomaterials and platinum microswimmers. First, carbon nanomaterials such as C
60, carbon nanotubes, and graphene have extraordinary physical properties that can be exploited for a wide range of applications, and thus have been studied extensively by a variety of experimental and theoretical techniques. In this dissertation, we study doping, defect, and many-body effects on the structural and electronic properties of carbon nanomaterials using a first-principles (it{ab initio}) approach (i.e. without using empirical parameters). Second, self-propelled microswimmers such as catalytically driven platinum microrods have a potential to be used as novel drug delivery vehicles. Many experiments on microswimmers have been done, but there has been no quantitative analysis on experimental data so far because different motions such as self-propelled and Brownian motions take place at the same time, leading to wrong interpretations of experimental results often. In this dissertation, we present novel data analysis methods for self-propelled microswimmers.
In Chapter 3, we study the doping effects of alkali and alkaline-earth atoms and C
8H
8 molecules on the structural, electronic, and superconducting properties of solid C
60 using
density functional theory (DFT). We show that there is no charge transfer between C
8H
8 and C
60 molecules in a C
8H
8/C
60 co-crystal using band-structure calculations. Using total-energy calculations, we also show that alkali atoms can fill the tetrahedral voids in a C
8H
8/C
60 co-crystal, leading to the formation of A
2(C
8H
8)C
60 (A = K, Rb, Cs). Finally, we show that ABa(C
8H
8)C
60 and ALi
2(C
8H
8)C
60 (A = K, Rb, Cs) – hypothetical three-electron-doped fcc (C
8H
8)C
60 co-crystals with the same crystal structure and doping level as superconducting A
3C
60 (A = K, Rb) – might have superconducting transition temperatures (T
c) of up to ∼50 K using McMillan formula.
Recently synthesized fluorographene, fully fluorinated graphene in a chair configuration, is a wide band-gap (E
g) semiconductor with an optical band gap of ∼3 eV. However, accurate first-principles calculations have shown that pristine fluorographene should have E
g of 5.4 – 7.5 eV. To explain this discrepancy, in Chapter 4, we study the defect effects of F vacancies, a Stone-Wales (SW) defect, C single vacancies and C double vacancies on E
g of fluorographene using
density functional theory and many-body perturbation theory within the GW
approximation. We show that F vacancies and a SW defect are not likely to affect E
g of fluorographene, whereas a C single vacancy with a doubly fluorinated C atom, a C double vacancy, and a C double vacancy with two doubly fluorinated C atoms, which are energetically more favorable than other C vacancies at a wide range of chemical potential of F (μ
F), lead to a it{GW} band gap of…
Advisors/Committee Members: Vincent Henry Crespi, Dissertation Advisor/Co-Advisor, Vincent Henry Crespi, Committee Chair/Co-Chair, Milton Walter Cole, Committee Member, Renee Denise Diehl, Committee Member, Eric M Mockensturm, Committee Member, Richard Wallace Robinett, Committee Member.
Subjects/Keywords: Fullerene; Fluorographene; Density Functional Theory; GW Approximation; Microswimmer; Chemotaxis
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APA (6th Edition):
Byun, Y. (2012). First-principles Theoretical Studies of Carbon Nanomaterials and New Data Analysis Methods for Catalytic Platinum Microswimmers. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/16249
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Byun, Young-moo. “First-principles Theoretical Studies of Carbon Nanomaterials and New Data Analysis Methods for Catalytic Platinum Microswimmers.” 2012. Thesis, Penn State University. Accessed April 10, 2021.
https://submit-etda.libraries.psu.edu/catalog/16249.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Byun, Young-moo. “First-principles Theoretical Studies of Carbon Nanomaterials and New Data Analysis Methods for Catalytic Platinum Microswimmers.” 2012. Web. 10 Apr 2021.
Vancouver:
Byun Y. First-principles Theoretical Studies of Carbon Nanomaterials and New Data Analysis Methods for Catalytic Platinum Microswimmers. [Internet] [Thesis]. Penn State University; 2012. [cited 2021 Apr 10].
Available from: https://submit-etda.libraries.psu.edu/catalog/16249.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Byun Y. First-principles Theoretical Studies of Carbon Nanomaterials and New Data Analysis Methods for Catalytic Platinum Microswimmers. [Thesis]. Penn State University; 2012. Available from: https://submit-etda.libraries.psu.edu/catalog/16249
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Iowa State University
5.
Ravi Kumar, Sandeep Kumar.
Experimental studies and simulation of laser ablation of high-density polyethylene films.
Degree: 2020, Iowa State University
URL: https://lib.dr.iastate.edu/etd/18033
► This thesis lays the groundwork for a simulation model for the laser ablation of polymer materials. A thorough review of the laser ablation of various…
(more)
▼ This thesis lays the groundwork for a simulation model for the laser ablation of polymer materials. A thorough review of the laser ablation of various polymer materials has been provided. The current trends and challenges in utilizing laser ablation for micro/nano manufacturing and information essential to the choice of an appropriate laser source for a polymer material have been provided. Experimental studies on laser ablation-based drilling of micro-holes on high-density polyethylene films have been performed. The influence of an increasing number of pulses and laser power on the depth and area of the micro-holes has been analyzed. The experimental results were utilized to validate a quantitative area-depth approximation model that was formulated based on the gain factors and the laser intensity profile. Additionally, a finite element method-based model has been developed for predicting the surface temperature and depth profile evolution with time during laser ablation of polymer materials.
Subjects/Keywords: area-depth approximation; high-density polyethylene; laser ablation; micro drilling; polymers
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APA (6th Edition):
Ravi Kumar, S. K. (2020). Experimental studies and simulation of laser ablation of high-density polyethylene films. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/18033
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ravi Kumar, Sandeep Kumar. “Experimental studies and simulation of laser ablation of high-density polyethylene films.” 2020. Thesis, Iowa State University. Accessed April 10, 2021.
https://lib.dr.iastate.edu/etd/18033.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ravi Kumar, Sandeep Kumar. “Experimental studies and simulation of laser ablation of high-density polyethylene films.” 2020. Web. 10 Apr 2021.
Vancouver:
Ravi Kumar SK. Experimental studies and simulation of laser ablation of high-density polyethylene films. [Internet] [Thesis]. Iowa State University; 2020. [cited 2021 Apr 10].
Available from: https://lib.dr.iastate.edu/etd/18033.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ravi Kumar SK. Experimental studies and simulation of laser ablation of high-density polyethylene films. [Thesis]. Iowa State University; 2020. Available from: https://lib.dr.iastate.edu/etd/18033
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Durham University
6.
Jochym, Dominik Bogdan.
Development of non-local density functional methods.
Degree: PhD, 2008, Durham University
URL: http://etheses.dur.ac.uk/2174/
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492886
► Density functional theory (DFT) is a popular approach to solving the many-electron Schrödinger equation, in order to investigate the properties of matter from first principles.…
(more)
▼ Density functional theory (DFT) is a popular approach to solving the many-electron Schrödinger equation, in order to investigate the properties of matter from first principles. While DFT can give the exact ground state electronic density of a system, in practice, an approximation is required for the many-body effects contained in the exchange-correlation functional. The accuracy of calculations performed using DFT is strongly related to the choice of approximation. In this thesis we will investigate and build upon a fully non-local approach to modeling exchange-correlation in the form of the weighted density approximation (WDA). Central to the WDA is the model function chosen for the coupling-constant averaged pair-correlation function (PCF). We show that a model PCF can be selected from a set to give excellent bulk properties for a particular system. However, this model is not necessarily transferable to other systems and there is no method of selecting an appropriate model from this set a priori. We suggest that the model PCF can be improved systematically by satisfying known physical constraints. One such constraint is the Kimball cusp condition, which we include in our model and implement. We demonstrate that surfaces are systems that require a non-local treatment of exchange-correlation by applying the WDA to metal surfaces and investigate the dissociative adsorption of H2 on the Cu(100) surface. A new framework for a model PCF with spin resolution is developed, providing a route for more physical constraints to be satisfied within a weighted spin density approximation (WSDA). A simple model is suggested and implemented and comparisons are made to the coupling-constant averaged PCF in the homogeneous electron gas. We then apply a selection of our new models to a number of materials and show that our model for the WSDA gives improved band gaps over the local density approximation. Application of the WSDA to spin polarised materials reveals shortcomings in our simple model. We then suggest further refinements to our implementation of the WSDA. It is expected that the inclusion of additional physical constraints will systematically improve results given in a weighted-density based approximation to exchange-correlation.
Subjects/Keywords: 530.15; Weighted density approximation
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APA (6th Edition):
Jochym, D. B. (2008). Development of non-local density functional methods. (Doctoral Dissertation). Durham University. Retrieved from http://etheses.dur.ac.uk/2174/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492886
Chicago Manual of Style (16th Edition):
Jochym, Dominik Bogdan. “Development of non-local density functional methods.” 2008. Doctoral Dissertation, Durham University. Accessed April 10, 2021.
http://etheses.dur.ac.uk/2174/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492886.
MLA Handbook (7th Edition):
Jochym, Dominik Bogdan. “Development of non-local density functional methods.” 2008. Web. 10 Apr 2021.
Vancouver:
Jochym DB. Development of non-local density functional methods. [Internet] [Doctoral dissertation]. Durham University; 2008. [cited 2021 Apr 10].
Available from: http://etheses.dur.ac.uk/2174/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492886.
Council of Science Editors:
Jochym DB. Development of non-local density functional methods. [Doctoral Dissertation]. Durham University; 2008. Available from: http://etheses.dur.ac.uk/2174/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492886
7.
Humberto Alencar de Paiva.
CaracterizaÃÃo energÃtica e estrutural da interaÃÃo DNA-cisplatina pela teoria do funcional da densidade.
Degree: 2007, Federal University of Uberlândia
URL: http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1143
► Study of the DNA-cisplatin system using the Density Functional Theory(DFT), compares the eficiency of the correlation and exchange functionals LDA and GGA (PBE) in the…
(more)
▼ Study of the DNA-cisplatin system using the Density Functional Theory(DFT), compares the eficiency of the correlation and exchange functionals LDA and GGA (PBE) in the simulation of the nitrogen bases as well as the basis sets DZP and DZ. Taking DZP and LDA options and with the use of the norm-conserved pseudopotentials Ceperley-Alder, simulate the sistems; cisplatina, isolated DNA bases, pairs of bases, DNA fragment with two pairs of bases GG and on the DNA-ciplatin system attached in GG and GA bases. It presents script of execution for the gradual approach of the real structure of the DNA. Reedits for these structures facts established in scientific literature, as it presents new facts for the electronic distribution of the DNA. Argues based in the interaction of dipoles between cisplatin and DNA, the existence of a potential barrier that restricts the possibility of the bond for the case of the linking in sequence GA of the DNA.
Estudo do sistema DNA-cisplatina usando a teoria do funcional da densidade (DFT) compara a eficiÃncia dos funcionais de correlaÃÃo e troca LDA e GGA(PBE) na simulaÃÃo das bases nitrogenadas como tambÃm os conjuntos de base DZP e DZ. Fazendo as opÃÃes DZP e LDA e com a utilizaÃÃo de pseudopotenciais Ceperley-Alder de norma conservada executa cÃlculos de simulaÃÃo da cisplatina, bases isoladas, pares de bases, fragmento de DNA com dois pares de bases GG e do sistema DNA-ciplatina ligada em conjunto de bases GG e AG. Apresenta roteiro de execuÃÃo para a gradual aproximaÃÃo da estrutura de fato do DNA. Reedita para essas estruturas resultados estabelecidos na literatura cientÃfica, como apresenta novos resultados para a distribuiÃÃo eletrÃnica do DNA. Apresenta argumenta ÃÃo, baseada na interaÃÃo de dipolos entre cisplatina e DNA para a existÃncia de uma barreira de potencial que restringe a possibilidade da ligaÃÃo para o caso da ligaÃÃo na sequencia guanina-adenina do DNA.
Advisors/Committee Members: Helio Ferreira dos Santos, Newton Martins Barbosa Neto, Eduardo Kojy Takahashi.
Subjects/Keywords: AproximaÃÃo de densidade local; Cisplatina; Generalized gradient approximation; Teoria do funcional da densidade; AproximaÃÃo de gradiente generalizado; Density functional theory; Cisplatin; FISICA; DNA; Local density approximation
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APA (6th Edition):
Paiva, H. A. d. (2007). CaracterizaÃÃo energÃtica e estrutural da interaÃÃo DNA-cisplatina pela teoria do funcional da densidade. (Thesis). Federal University of Uberlândia. Retrieved from http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1143
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Paiva, Humberto Alencar de. “CaracterizaÃÃo energÃtica e estrutural da interaÃÃo DNA-cisplatina pela teoria do funcional da densidade.” 2007. Thesis, Federal University of Uberlândia. Accessed April 10, 2021.
http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1143.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Paiva, Humberto Alencar de. “CaracterizaÃÃo energÃtica e estrutural da interaÃÃo DNA-cisplatina pela teoria do funcional da densidade.” 2007. Web. 10 Apr 2021.
Vancouver:
Paiva HAd. CaracterizaÃÃo energÃtica e estrutural da interaÃÃo DNA-cisplatina pela teoria do funcional da densidade. [Internet] [Thesis]. Federal University of Uberlândia; 2007. [cited 2021 Apr 10].
Available from: http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1143.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Paiva HAd. CaracterizaÃÃo energÃtica e estrutural da interaÃÃo DNA-cisplatina pela teoria do funcional da densidade. [Thesis]. Federal University of Uberlândia; 2007. Available from: http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1143
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
8.
Humberto Alencar de Paiva.
Caracterização energética e estrutural da interação DNA-cisplatina pela teoria do funcional da densidade.
Degree: 2007, Federal University of Uberlândia
URL: http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1143
► Estudo do sistema DNA-cisplatina usando a teoria do funcional da densidade (DFT) compara a eficiência dos funcionais de correlação e troca LDA e GGA(PBE) na…
(more)
▼ Estudo do sistema DNA-cisplatina usando a teoria do funcional da densidade (DFT) compara a eficiência dos funcionais de correlação e troca LDA e GGA(PBE) na simulação das bases nitrogenadas como também os conjuntos de base DZP e DZ. Fazendo as opções DZP e LDA e com a utilização de pseudopotenciais Ceperley-Alder de norma conservada executa cálculos de simulação da cisplatina, bases isoladas, pares de bases, fragmento de DNA com dois pares de bases GG e do sistema DNA-ciplatina ligada em conjunto de bases GG e AG. Apresenta roteiro de execução para a gradual aproximação da estrutura de fato do DNA. Reedita para essas estruturas resultados estabelecidos na literatura científica, como apresenta novos resultados para a distribuição eletrônica do DNA. Apresenta argumenta ção, baseada na interação de dipolos entre cisplatina e DNA para a existência de uma barreira de potencial que restringe a possibilidade da ligação para o caso da ligação na sequencia guanina-adenina do DNA.
Study of the DNA-cisplatin system using the Density Functional Theory(DFT), compares the eficiency of the correlation and exchange functionals LDA and GGA (PBE) in the simulation of the nitrogen bases as well as the basis sets DZP and DZ. Taking DZP and LDA options and with the use of the norm-conserved pseudopotentials Ceperley-Alder, simulate the sistems; cisplatina, isolated DNA bases, pairs of bases, DNA fragment with two pairs of bases GG and on the DNA-ciplatin system attached in GG and GA bases. It presents script of execution for the gradual approach of the real structure of the DNA. Reedits for these structures facts established in scientific literature, as it presents new facts for the electronic distribution of the DNA. Argues based in the interaction of dipoles between cisplatin and DNA, the existence of a potential barrier that restricts the possibility of the bond for the case of the linking in sequence GA of the DNA.
Advisors/Committee Members: Eduardo Kojy Takahashi, Newton Martins Barbosa Neto, Helio Ferreira dos Santos.
Subjects/Keywords: FISICA; Teoria do funcional da densidade; Aproximação de densidade local; Aproximação de gradiente generalizado; DNA; Cisplatina; Density functional theory; Local density approximation; Generalized gradient approximation; Cisplatin
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APA (6th Edition):
Paiva, H. A. d. (2007). Caracterização energética e estrutural da interação DNA-cisplatina pela teoria do funcional da densidade. (Thesis). Federal University of Uberlândia. Retrieved from http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1143
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Paiva, Humberto Alencar de. “Caracterização energética e estrutural da interação DNA-cisplatina pela teoria do funcional da densidade.” 2007. Thesis, Federal University of Uberlândia. Accessed April 10, 2021.
http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1143.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Paiva, Humberto Alencar de. “Caracterização energética e estrutural da interação DNA-cisplatina pela teoria do funcional da densidade.” 2007. Web. 10 Apr 2021.
Vancouver:
Paiva HAd. Caracterização energética e estrutural da interação DNA-cisplatina pela teoria do funcional da densidade. [Internet] [Thesis]. Federal University of Uberlândia; 2007. [cited 2021 Apr 10].
Available from: http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1143.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Paiva HAd. Caracterização energética e estrutural da interação DNA-cisplatina pela teoria do funcional da densidade. [Thesis]. Federal University of Uberlândia; 2007. Available from: http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1143
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Florida
9.
Chu, Iek Heng.
Computational Studies of Excited States and Electron Transfer in Nanoscale Materials.
Degree: PhD, Physics, 2014, University of Florida
URL: https://ufdc.ufl.edu/UFE0046927
► Nanoscale materials have become mainstream research topics in physics, chemistry, and material science because they can exhibit unique physical properties due to quantum mechanical effects.…
(more)
▼ Nanoscale materials have become mainstream research topics in physics, chemistry, and material science because they can exhibit unique physical properties due to quantum mechanical effects. Potential applications of these materials, such as photovoltaic or optoelectronic devices, require knowledge of the electronic structure and charge transfer properties of the system. The
density functional theory (DFT) can usually provide many correct physical properties of systems. However, when information regarding the electronic band gap and excited states is of interest, corrections to DFT such as via the GW method need to be adopted. In this dissertation, we first give a general overview of the theories and methods including DFT, the GW method, and other approaches used for studying charge transfer.
Advisors/Committee Members: CHENG,HAI PING (committee chair), STANTON,CHRISTOPHER JAY (committee member), TRICKEY,SAMUEL B (committee member), GUO,JING (committee member).
Subjects/Keywords: Approximation; Atoms; Charge density; Conduction bands; Electronics; Electrons; Energy; Isomers; Molecules; Phonons; carbon-nanotube – density-functional-theory – electron-transfer – electronic-structure – gw-approximation – nanoscale – quantum-dot – spinel-nitrides
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APA (6th Edition):
Chu, I. H. (2014). Computational Studies of Excited States and Electron Transfer in Nanoscale Materials. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0046927
Chicago Manual of Style (16th Edition):
Chu, Iek Heng. “Computational Studies of Excited States and Electron Transfer in Nanoscale Materials.” 2014. Doctoral Dissertation, University of Florida. Accessed April 10, 2021.
https://ufdc.ufl.edu/UFE0046927.
MLA Handbook (7th Edition):
Chu, Iek Heng. “Computational Studies of Excited States and Electron Transfer in Nanoscale Materials.” 2014. Web. 10 Apr 2021.
Vancouver:
Chu IH. Computational Studies of Excited States and Electron Transfer in Nanoscale Materials. [Internet] [Doctoral dissertation]. University of Florida; 2014. [cited 2021 Apr 10].
Available from: https://ufdc.ufl.edu/UFE0046927.
Council of Science Editors:
Chu IH. Computational Studies of Excited States and Electron Transfer in Nanoscale Materials. [Doctoral Dissertation]. University of Florida; 2014. Available from: https://ufdc.ufl.edu/UFE0046927
10.
ORHAN, OKAN KARACA.
Corrective First-Principles Approaches for the Theoretical Spectroscopy of Transition-Metal Systems.
Degree: School of Physics. Discipline of Physics, 2018, Trinity College Dublin
URL: http://hdl.handle.net/2262/84975
► Density-functional theory within its practical, widespread Kohn-Sham formalism (KS-DFT), is an effective approach for providing the starting point for advanced first-principles spectroscopy simulations of molecules…
(more)
▼ Density-functional theory within its practical, widespread Kohn-Sham formalism (KS-DFT), is an effective approach for providing the starting point for advanced first-principles spectroscopy simulations of molecules and solids in the linear-response regime. Within available approximations for the electronic exchange-correlation energy, however, KS-DFT exhibits certain systematic errors such as self-interaction error (SIE), which dominates the error in insulating and optical gaps. Particularly, transition-metal systems in general have large SIE that manifest as large delocalisation error of 3d states of such systems. Consequently, spectroscopy simulations of these systems starting from KS-DFT are unreliable. Here, we introduce computationally feasible and quantitatively accurate corrective approaches to encounter such errors in first-principles spectroscopy simulations, particularly with a view to enabling future high-throughput spectroscopy for transition-metal systems.
Accurate spectra of selected noble-metal solids and their alloys were obtained using the random-phase
approximation (RPA) on top of G0W0 quasiparticle-corrected band-structures using the first-principle stretching operators, which modify the electronic bands around the Fermi level to imitate the non-local many-body effects. Quantitative accuracy is achieved while preserving minimal additional costs. A number of promising candidate alloys are predicted for plasmonic applications.
The time-domain extension of DFT+U, namely TDDFT+U, was developed and implemented with a linear-scaling framework. This corrects SIE of particle-hole pairs built from localised orbitals in the context of linear-response time-dependent DFT (TDDFT) within adiabatic semi-local approximations for transition-metal systems. It is demonstrated using representative three coordination complexes that TDDFT+U can significantly improve the descriptions of low-lying excitations accurately from first-principles.
Despite its great success, conventional DFT+U fails to predict the insulating gap of TiO2 as its valance edge states are dominated by 2p states of O atoms. Hence, a +U correction is required for both the 3d states of Ti and the 2p states of O, giving DFT+Ud+Up. The insulating gaps of TiO2-rutile and TiO2-anatase were calculated accurately within DFT+Ud+Up with Hubbard U and Hund's J parameters calculated from first-principles. Furthermore, the defect states of neutral O vacancies in TiO2-rutile and TiO2-anatase were investigated within the same approach. Our calculations provide a first-principles assessment of the vacancy states in these important materials, and show that DFT+U can behave well for closed-shell transition-metal systems if used with appropriate care.
Advisors/Committee Members: O'Regan, David.
Subjects/Keywords: time-dependent density-functional theory; density-functional theory; GW approximation; Hubbard correction; transition-metals; theoretical spectroscopy
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APA (6th Edition):
ORHAN, O. K. (2018). Corrective First-Principles Approaches for the Theoretical Spectroscopy of Transition-Metal Systems. (Thesis). Trinity College Dublin. Retrieved from http://hdl.handle.net/2262/84975
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
ORHAN, OKAN KARACA. “Corrective First-Principles Approaches for the Theoretical Spectroscopy of Transition-Metal Systems.” 2018. Thesis, Trinity College Dublin. Accessed April 10, 2021.
http://hdl.handle.net/2262/84975.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
ORHAN, OKAN KARACA. “Corrective First-Principles Approaches for the Theoretical Spectroscopy of Transition-Metal Systems.” 2018. Web. 10 Apr 2021.
Vancouver:
ORHAN OK. Corrective First-Principles Approaches for the Theoretical Spectroscopy of Transition-Metal Systems. [Internet] [Thesis]. Trinity College Dublin; 2018. [cited 2021 Apr 10].
Available from: http://hdl.handle.net/2262/84975.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
ORHAN OK. Corrective First-Principles Approaches for the Theoretical Spectroscopy of Transition-Metal Systems. [Thesis]. Trinity College Dublin; 2018. Available from: http://hdl.handle.net/2262/84975
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Guelph
11.
Buraczynski, Matthew.
Static response of neutron matter.
Degree: MS, Department of Physics, 2018, University of Guelph
URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14295
► We investigate the problem of periodically modulated strongly interacting neutron matter. We carry out ab initio non-perturbative auxiliary-field diffusion Monte Carlo calculations using an external…
(more)
▼ We investigate the problem of periodically modulated strongly interacting neutron matter. We carry out ab initio non-perturbative auxiliary-field diffusion Monte Carlo calculations using an external sinusoidal potential in addition to phenomenological two- and three-nucleon interactions. Several choices for the wave function ansatz are explored and special care is taken to extrapolate finite-sized results to the thermodynamic limit. We perform calculations at various densities as well as at different strengths and periodicities of the one-body potential. Our microscopic results are then used to constrain the isovector term from energy-
density functional theories of nuclei at many different densities, while making sure to separate isovector contributions from bulk properties. Lastly, we use our results to extract the static
density-density linear response function of neutron matter at different densities. Our findings provide insights into inhomogeneous neutron matter and are related to the physics of neutron-star crusts and neutron-rich nuclei.
Advisors/Committee Members: Gezerlis, Alexandros (advisor).
Subjects/Keywords: nuclear physics; neutrons; quantum monte carlo; many-body physics; neutron stars; AFDMC; static response; energy density functional theory; local density approximation
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APA (6th Edition):
Buraczynski, M. (2018). Static response of neutron matter. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14295
Chicago Manual of Style (16th Edition):
Buraczynski, Matthew. “Static response of neutron matter.” 2018. Masters Thesis, University of Guelph. Accessed April 10, 2021.
https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14295.
MLA Handbook (7th Edition):
Buraczynski, Matthew. “Static response of neutron matter.” 2018. Web. 10 Apr 2021.
Vancouver:
Buraczynski M. Static response of neutron matter. [Internet] [Masters thesis]. University of Guelph; 2018. [cited 2021 Apr 10].
Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14295.
Council of Science Editors:
Buraczynski M. Static response of neutron matter. [Masters Thesis]. University of Guelph; 2018. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/14295
UCLA
12.
Arntsen, Christopher.
Electronic properties of organic photovoltaic materials.
Degree: Chemistry, 2014, UCLA
URL: http://www.escholarship.org/uc/item/6b1186c0
► Organic solar cells have gained much attention as an inexpensive alternative to traditional inorganic cells. While experimental efforts have steadily improved the efficiency of organic…
(more)
▼ Organic solar cells have gained much attention as an inexpensive alternative to traditional inorganic cells. While experimental efforts have steadily improved the efficiency of organic devices, a large portion of the improvements have been the result of trial-and-error. Therefore, it would be ideal to be able to use theory to predict which types of materials would produce the most efficient devices. This dissertation presents a series of theoretical studies designed to improve understanding of what makes certain solar cells perform well and to serve as a predictive tool to screen potential new materials.First, a study of electron transfer in pentacene dimers is presented. The study compares several methods for calculating the electronic transfer integral, including time-dependent density function theory, a time dependent semi-empirical method, and several static calculations. The results demonstrate that at large separations, static calculations can underestimate the strength of coupling. Next, electronic coupling in fullerenes is calculated. In this section, a method for mimicking bulk chemical environments in film through the use of solvation and application of electric fields is developed. The method is a applied to a number of fullerenes used in organic solar cells, and compared with experimental data on local and bulk electron mobilities. Comparing the theory and experiment allows one to identify beneficial self-assembly behavior in the fullerenes studied. This method is then extended to a calculation method we have termed direct delocalization. In this method, a field is applied directly to the Fock matrix in order to delocalize frontier orbitals across a dimer. Once this is accomplished, electronic transfer time is calculated within the standard Marcus theory framework. The results are compared to the more thorough methods described above, and found to be in agreement.Next, the formulation of a stochastic approach to the GW approximation is presented. In this section, a method for calculating the polarization self-energy with stochastic orbitals is introduced. The method is highly efficient, achieving near linear scaling with respect to system size, compared with the theoretical fourth order scaling. The method is applied to large silicon clusters and several fullerenes to accurately calculate quasiparticle energies. Finally, in the last two chapters, several methods for studying plasmons are presented. The first presents a method for studying the interaction between molecules and plasmonic materials. The method interfaces a semiempirical quantum mechanical calculation (to study the molecules) with a finite- ifference time-domain (FDTD) calculation (to study the plasmonic material). The study shows that plasmon propagation can be heavily influenced by the presence of a molecule. In the last section, an alternative FDTD method is presented. This method, labeled near-field, is a time-dependent version of the quasistatic frequency-dependent Poisson algorithm. This approach is advantageous in that it allows for…
Subjects/Keywords: Physical chemistry; density functional theory; finite-difference time-domain; gw approximation; organic photovoltaics
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APA (6th Edition):
Arntsen, C. (2014). Electronic properties of organic photovoltaic materials. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/6b1186c0
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Arntsen, Christopher. “Electronic properties of organic photovoltaic materials.” 2014. Thesis, UCLA. Accessed April 10, 2021.
http://www.escholarship.org/uc/item/6b1186c0.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Arntsen, Christopher. “Electronic properties of organic photovoltaic materials.” 2014. Web. 10 Apr 2021.
Vancouver:
Arntsen C. Electronic properties of organic photovoltaic materials. [Internet] [Thesis]. UCLA; 2014. [cited 2021 Apr 10].
Available from: http://www.escholarship.org/uc/item/6b1186c0.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Arntsen C. Electronic properties of organic photovoltaic materials. [Thesis]. UCLA; 2014. Available from: http://www.escholarship.org/uc/item/6b1186c0
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Illinois – Chicago
13.
Shi, Bin.
First Principles Studies of Electronic and Optical Properties of Transition Metal Oxide Clusters.
Degree: 2019, University of Illinois – Chicago
URL: http://hdl.handle.net/10027/23625
► Nanostructured clusters involving transition metal oxides constitute one of the most interesting classes of materials, as they exhibit a wide range of structures and properties…
(more)
▼ Nanostructured clusters involving transition metal oxides constitute one of the most interesting classes of materials, as they exhibit a wide range of structures and properties that can lead to many important potential applications. From a computational perspective, transition metal oxide nanostructures present challenges for both ground state and excited state properties, due to the nature of confinement, and localized and strongly correlated nature of their d electrons. In this thesis I present results and analyses of my computations on two systems: (i) copper oxide cluster anions and (ii) building units of one of the metal organic frameworks (MOFs), IRMOF-1, and its analogues. For the copper oxide cluster anions, the photoelectron spectra of Cu2O–, CuO–, CuO2– and CuO3– clusters are calculated using
density functional theory (DFT) and many-body perturbation theory within the GW
approximation. My computational results and existing experimental data are systematically compared with a focus on the comparison of semi-local and hybrid functionals. The presence of self-interaction error within different levels of theories and its mitigating ways are also discussed. For the building blocks of MOFs, the geometries are optimized using DFT and absorption spectra are computed using time-dependent DFT. The gradual trends of geometric parameters and optical band gaps in the analogues of IRMOF-1 are analyzed. The transition mechanisms near the band edge are also discussed using
density of states, integrated oscillator strength, and orbital characters analysis.
Advisors/Committee Members: Ogut, Serdar (advisor), Klie, Robert (committee member), Khalili-Araghi, Fatemeh (committee member), Grein, Christoph (committee member), Iddir, Hakim (committee member), Ogut, Serdar (chair).
Subjects/Keywords: first principles; density functional theory; GW approximation; transition metal oxide; copper oxide; metal organic frameworks
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APA (6th Edition):
Shi, B. (2019). First Principles Studies of Electronic and Optical Properties of Transition Metal Oxide Clusters. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/23625
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Shi, Bin. “First Principles Studies of Electronic and Optical Properties of Transition Metal Oxide Clusters.” 2019. Thesis, University of Illinois – Chicago. Accessed April 10, 2021.
http://hdl.handle.net/10027/23625.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Shi, Bin. “First Principles Studies of Electronic and Optical Properties of Transition Metal Oxide Clusters.” 2019. Web. 10 Apr 2021.
Vancouver:
Shi B. First Principles Studies of Electronic and Optical Properties of Transition Metal Oxide Clusters. [Internet] [Thesis]. University of Illinois – Chicago; 2019. [cited 2021 Apr 10].
Available from: http://hdl.handle.net/10027/23625.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Shi B. First Principles Studies of Electronic and Optical Properties of Transition Metal Oxide Clusters. [Thesis]. University of Illinois – Chicago; 2019. Available from: http://hdl.handle.net/10027/23625
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Rice University
14.
Garza Gonzalez, Alejandro Jesus.
Combination of Wavefunction and Density Functional Approximations for Describing Electronic Correlation.
Degree: PhD, Natural Sciences, 2016, Rice University
URL: http://hdl.handle.net/1911/95554
► Perhaps the most important approximations to the electronic structure problem in quantum chemistry are those based on coupled cluster and density functional theories. Coupled cluster…
(more)
▼ Perhaps the most important approximations to the electronic structure problem in quantum chemistry are those based on coupled cluster and
density functional theories. Coupled cluster theory has been called the ``gold standard'' of quantum chemistry due to the high accuracy that it achieves for weakly correlated systems. Kohn – Sham
density functionals based on semilocal approximations are, without a doubt, the most widely used methods in chemistry and material science because of their high accuracy/cost ratio. The root of the success of coupled cluster and
density functionals is their ability to efficiently describe the dynamic part of the electron correlation. However, both traditional coupled cluster and
density functional approximations may
fail catastrophically when substantial static correlation is present. This severely limits the applicability of these methods to a plethora of important chemical and physical problems such as, e.g., the description of bond breaking,
transition states, transition metal-,
lanthanide- and actinide-containing compounds, and superconductivity.
In an attempt to tackle this problem,
nonstandard (single-reference) coupled cluster-based techniques that aim to describe static correlation
have been recently developed:
pair coupled cluster doubles (pCCD) and singlet-paired coupled cluster doubles (CCD0). The ability to describe static correlation in pCCD and CCD0 comes, however, at the expense of important amounts of dynamic correlation so that the high accuracy of standard coupled cluster becomes unattainable. Thus, the reliable and efficient description of static and dynamic correlation in a
simultaneous manner remains an open problem for quantum chemistry and many-body theory in general.
In this thesis, different ways to combine pCCD and CCD0 with
density
functionals in order to describe static and dynamic correlation
simultaneously (and efficiently) are explored. The combination of
wavefunction and
density functional methods has a long history in
quantum chemistry (practical implementations have appeared in the
literature since the 1970s). However, this kind of techniques have not achieved widespread use due to problems such as double counting of
correlation and the symmetry dilemma – the fact that wavefunction
methods respect the symmetries of Hamiltonian, while modern
functionals are designed to work with broken symmetry densities. Here, particular mathematical features of pCCD and CCD0 are exploited
to avoid these problems in an efficient manner. The two resulting families of approximations, denoted as pCCD+DFT and CCD0+DFT, are
shown to be able to describe static and dynamic correlation in standard benchmark calculations. Furthermore, it is also shown that CCD0+DFT lends itself to combination with correlation from the direct random phase
approximation (dRPA). Inclusion of dRPA in the long-range via the technique of range-separation allows for the description of dispersion correlation, the remaining part of the
correlation. Thus, when combined with the dRPA, CCD0+DFT can…
Advisors/Committee Members: Scuseria, Gustavo E (advisor).
Subjects/Keywords: Coupled Cluster; Density Functionals; Static Correlation; Dynamic Correlation; Dispersion Correlation; Random Phase Approximation
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APA ·
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APA (6th Edition):
Garza Gonzalez, A. J. (2016). Combination of Wavefunction and Density Functional Approximations for Describing Electronic Correlation. (Doctoral Dissertation). Rice University. Retrieved from http://hdl.handle.net/1911/95554
Chicago Manual of Style (16th Edition):
Garza Gonzalez, Alejandro Jesus. “Combination of Wavefunction and Density Functional Approximations for Describing Electronic Correlation.” 2016. Doctoral Dissertation, Rice University. Accessed April 10, 2021.
http://hdl.handle.net/1911/95554.
MLA Handbook (7th Edition):
Garza Gonzalez, Alejandro Jesus. “Combination of Wavefunction and Density Functional Approximations for Describing Electronic Correlation.” 2016. Web. 10 Apr 2021.
Vancouver:
Garza Gonzalez AJ. Combination of Wavefunction and Density Functional Approximations for Describing Electronic Correlation. [Internet] [Doctoral dissertation]. Rice University; 2016. [cited 2021 Apr 10].
Available from: http://hdl.handle.net/1911/95554.
Council of Science Editors:
Garza Gonzalez AJ. Combination of Wavefunction and Density Functional Approximations for Describing Electronic Correlation. [Doctoral Dissertation]. Rice University; 2016. Available from: http://hdl.handle.net/1911/95554
University of Minnesota
15.
Kargas, Nikolaos.
Tensor Modeling of High-dimensional Distributions and Nonlinear Functions.
Degree: PhD, Electrical/Computer Engineering, 2020, University of Minnesota
URL: http://hdl.handle.net/11299/218706
► Distribution estimation lies at the heart of statistical learning. Given the probability distribution of a set of random variables it is possible to compute marginal…
(more)
▼ Distribution estimation lies at the heart of statistical learning. Given the probability distribution of a set of random variables it is possible to compute marginal or conditional probabilities, moments and design optimal estimators. In this dissertation, we reveal an interesting link between multivariate statistics and tensors and propose a novel framework for joint Probability Mass Function (PMF) estimation given limited and possibly very incomplete data samples. We show that any joint PMF admits a naive Bayes model representation with a finite-alphabet latent variable. If the latent alphabet size is under a certain threshold, then the joint PMF of an arbitrary number of random variables can be identified from three-dimensional marginal distributions. We develop a practical and efficient algorithm that is shown to work well on both simulated and real data. We also extend our approach to mixture models of continuous variables. We consider the special case of mixture models whose component distributions factor into the product of the associated marginals and propose a two-stage approach which recovers the component distributions of the mixture under a smoothness condition. The second part of the dissertation focuses on the problem of nonlinear function approximation. In practice, when labeled data are available we are often interested in methods that directly model the relationship or the conditional distribution function between the features and the target variable. It is desirable to develop methods that are expressive enough to capture a wide class of functions and at the same time are scalable and efficient. We show that the canonical polyadic decomposition model offers an appealing solution for modeling and learning a general nonlinear function. We formulate the problem as a smooth tensor decomposition problem with missing data and prove that under certain conditions correct nonlinear system identification is possible. We extend our method to multivariate functions of continuous inputs by proposing a generalization of the canonical polyadic decomposition from tensors to multivariate functions. The merits of our approach are illustrated using several synthetic and real multivariate regression tasks.
Subjects/Keywords: density estimation; function approximation; machine learning; supervised learning; tensor decomposition; unsupervised learning
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APA (6th Edition):
Kargas, N. (2020). Tensor Modeling of High-dimensional Distributions and Nonlinear Functions. (Doctoral Dissertation). University of Minnesota. Retrieved from http://hdl.handle.net/11299/218706
Chicago Manual of Style (16th Edition):
Kargas, Nikolaos. “Tensor Modeling of High-dimensional Distributions and Nonlinear Functions.” 2020. Doctoral Dissertation, University of Minnesota. Accessed April 10, 2021.
http://hdl.handle.net/11299/218706.
MLA Handbook (7th Edition):
Kargas, Nikolaos. “Tensor Modeling of High-dimensional Distributions and Nonlinear Functions.” 2020. Web. 10 Apr 2021.
Vancouver:
Kargas N. Tensor Modeling of High-dimensional Distributions and Nonlinear Functions. [Internet] [Doctoral dissertation]. University of Minnesota; 2020. [cited 2021 Apr 10].
Available from: http://hdl.handle.net/11299/218706.
Council of Science Editors:
Kargas N. Tensor Modeling of High-dimensional Distributions and Nonlinear Functions. [Doctoral Dissertation]. University of Minnesota; 2020. Available from: http://hdl.handle.net/11299/218706
16.
Kang, Sang Jin.
Advances in the Modeling of Heavy-tailed Distributions.
Degree: 2018, University of Western Ontario
URL: https://ir.lib.uwo.ca/etd/6003
► Several advances are proposed in connection with the approximation and estimation of heavy-tailed distributions, some of which also apply to other types of distributions. It…
(more)
▼ Several advances are proposed in connection with the approximation and estimation of heavy-tailed distributions, some of which also apply to other types of distributions. It is first explained that on initially applying the Esscher transform to heavy-tailed density functions such as the Pareto, Student-t and Cauchy densities, one can utilize a moment-based technique whereby the tilted density functions are expressed as the product of a base density function and a polynomial adjustment. Alternatively, density approximants can be secured by appropriately truncating the distributions or mapping them onto compact supports. The validity of these approaches is corroborated by simulation studies. Extensions to the context of density estimation, in which case sample moments are employed in lieu of exact moments are discussed, and illustrative applications involving actuarial data sets are presented. Novel approaches involving making use of the Box-Cox transform in conjunction with empirical saddlepoint density estimates and generalized beta density functions are introduced for determining the endpoints of empirical distribution. Additionally, an iterative algorithm and a technique relying on approximating a function by means of Bernstein polynomials are proposed for obtaining smooth bona fide density functions. Finally, a polynomial adjustment is applied to a bivariate empirical saddlepoint estimate which is obtained from a sample estimate of the bivariate cumulant generating function. A significant contribution of this dissertation resides in the implementation of the proposed methodologies such as the constrained estimation of the four parameters of the generalized beta distribution and the adjusted bivariate empirical saddlepoint density estimation technique in the symbolic computing package Mathematica.
Subjects/Keywords: Density approximation; heavy-tailed distributions; bona fide density estimates; empirical distributional endpoints; empirical saddlepoint estimates; bivariate density estimation; Applied Statistics; Statistical Methodology
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APA (6th Edition):
Kang, S. J. (2018). Advances in the Modeling of Heavy-tailed Distributions. (Thesis). University of Western Ontario. Retrieved from https://ir.lib.uwo.ca/etd/6003
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kang, Sang Jin. “Advances in the Modeling of Heavy-tailed Distributions.” 2018. Thesis, University of Western Ontario. Accessed April 10, 2021.
https://ir.lib.uwo.ca/etd/6003.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kang, Sang Jin. “Advances in the Modeling of Heavy-tailed Distributions.” 2018. Web. 10 Apr 2021.
Vancouver:
Kang SJ. Advances in the Modeling of Heavy-tailed Distributions. [Internet] [Thesis]. University of Western Ontario; 2018. [cited 2021 Apr 10].
Available from: https://ir.lib.uwo.ca/etd/6003.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kang SJ. Advances in the Modeling of Heavy-tailed Distributions. [Thesis]. University of Western Ontario; 2018. Available from: https://ir.lib.uwo.ca/etd/6003
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Western Ontario
17.
Zareamoghaddam, Hossein.
Advances in Semi-Nonparametric Density Estimation and Shrinkage Regression.
Degree: 2018, University of Western Ontario
URL: https://ir.lib.uwo.ca/etd/5234
► This thesis advocates the use of shrinkage and penalty techniques for estimating the parameters of a regression model that comprises both parametric and nonparametric components…
(more)
▼ This thesis advocates the use of shrinkage and penalty techniques for estimating the parameters of a regression model that comprises both parametric and nonparametric components and develops semi-nonparametric density estimation methodologies that are applicable in a regression context.
First, a moment-based approach whereby a univariate or bivariate density function is approximated by means of a suitable initial density function that is adjusted by a linear combination of orthogonal polynomials is introduced. Such adjustments are shown to be mathematically equivalent to making use of standard polynomials in one or two variables. Once extended to apply to density estimation, in which case the sample moments are being utilized, the proposed technique readily lends itself to the modeling of massive univariate or bivariate data sets. As well, the resulting density functions are shown to be expressible as kernel density estimates via the Christoffel-Darboux formula. Additionally, it is established that a set of n observations is entirely specified by its first n moments.
It is also explained that a univariate bona fide density approximation can be obtained by assuming that the derivative of the logarithm of the density function under consideration is expressible as a rational function or a polynomial. An explicit representation of the density function so obtained is derived and jointly sufficient statistics for its parameters are identified. Then, extensions of the proposed methodology to density estimation and multivariate settings are discussed. As a matter of fact, this approach constitutes a generalization of Pearson's system of frequency curves. Several illustrative examples are presented including regression applications.
Finally, an iterative algorithm involving shrinkage and pretest techniques is introduced for estimating the parameters of a certain semi-nonparametric model. It is theoretically established and numerically verified that the proposed estimators are more accurate than the unrestricted ones. This methodology is successfully applied to a mass spectrometry data set.
Subjects/Keywords: moments based density approximation; bivariate density estimation; differentiated log-density approximants; Pearson curves; semi-nonparametric model; shrinkage estimation; Applied Statistics; Multivariate Analysis; Other Statistics and Probability; Probability; Statistical Methodology
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APA (6th Edition):
Zareamoghaddam, H. (2018). Advances in Semi-Nonparametric Density Estimation and Shrinkage Regression. (Thesis). University of Western Ontario. Retrieved from https://ir.lib.uwo.ca/etd/5234
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Zareamoghaddam, Hossein. “Advances in Semi-Nonparametric Density Estimation and Shrinkage Regression.” 2018. Thesis, University of Western Ontario. Accessed April 10, 2021.
https://ir.lib.uwo.ca/etd/5234.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zareamoghaddam, Hossein. “Advances in Semi-Nonparametric Density Estimation and Shrinkage Regression.” 2018. Web. 10 Apr 2021.
Vancouver:
Zareamoghaddam H. Advances in Semi-Nonparametric Density Estimation and Shrinkage Regression. [Internet] [Thesis]. University of Western Ontario; 2018. [cited 2021 Apr 10].
Available from: https://ir.lib.uwo.ca/etd/5234.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zareamoghaddam H. Advances in Semi-Nonparametric Density Estimation and Shrinkage Regression. [Thesis]. University of Western Ontario; 2018. Available from: https://ir.lib.uwo.ca/etd/5234
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Temple University
18.
Xiao, Bing.
Phase Transitions, Magnetism and Surface Adsorptions Assessed by Meta-GGA Functionals and Random Phase Approximation.
Degree: PhD, 2014, Temple University
URL: http://digital.library.temple.edu/u?/p245801coll10,294630
► Physics
The meta-GGA functionals and random phase approximation are tested for phase transitions and a strongly correlated transition metal oxide in this dissertation. One of…
(more)
▼ Physics
The meta-GGA functionals and random phase approximation are tested for phase transitions and a strongly correlated transition metal oxide in this dissertation. One of the latest meta-GGA functionals is also employed to study the van der Waals bound system in surface science. Our main purpose is to reveal the performance of new exchange-correlation functionals on various properties and systems. We are also interested in seeking the possible relationship between the performance of a semilocal functional and its exchange enhancement factor. We have studied the structural phase transitions in crystalline Si (insulator to metal), SiO2 (insulator to insulator) and Zr (metal to metal) systems, as a test of exchange energy semilocal functionals on Jacob's ladder. Our results confirm the energy-geometry dilemma of GGAs in three systems. The most sophisticated non-empirical meta-generalized gradient approximations (meta-GGAs) such as TPSS (Tao-Perdew-Staroveov-Scuseria) and revTPSS (revised TPSS) give better lattice constants than PBE, but the phase transition parameters (energy difference and transition pressure) are smaller and less realistic than those from the latter GGA. However, the recent functionals of meta-GGA made simple family (MGGA_MS) behave differently to those previous meta-GGAs, predicting larger and more realistic phase transition parameters. Meanwhile, MGGA_MS also delivers the equilibrium geometry of crystalline materials similar to previous non-empirical meta-GGAs. In contrast to semilocal functionals, the nonlocal functionals such as the range-separated hybrid functional HSE06 (Heyd-Scuseria-Ernzerhof) and non-self consistent random phase approximation (RPA) are not only able to give the accurate equilibrium geometry , but also predict the realistic phase transition parameters for Si and SiO2 systems. The ground state of rutile-type vanadium dioxide (R-VO2) represents a great challenge to the current density functional theory. In this dissertation, we investigated the electronic structures and magnetism of R-VO2 using exchange-correlation functionals of all five rungs on Jacob's ladder. Our calculations show that all semilocal functionals (LSDA, GGAs and meta-GGAs) and hybrid functionals (HSE06) stabilize the spin-polarized states (ferromagnetic and anti-ferromagnetic states) over non-magnetic state, which are completely opposite to experimental observation. Surprisingly, LSDA gives the best energetic descriptions for magnetic and non-magnetic phases of R-VO2 among semilocal functionals and HSE06. Otherwise, RPA calculations are highly dependent on the inputs in the spin polarized case. With PBE inputs, RPA also fails, giving lower energies for spin-polarized states than for the non-magnetic phase. Meanwhile, the results are reversed using LSDA inputs. From the computed equilibrium cell volume, we observe the error cancellation in the exchange-correlation hole of most semilocal functionals in the spin-polarized calculations. LSDA and RPA do not fit to this picture. By analyzing the local…
Advisors/Committee Members: Perdew, John P.;, Perdew, John P., Ruzsinszky, Adrienn, Wu, Xifan, Yuen, Tan, Tao, Jianmin;.
Subjects/Keywords: Physics; Condensed matter physics; Chemistry;
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APA ·
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APA (6th Edition):
Xiao, B. (2014). Phase Transitions, Magnetism and Surface Adsorptions Assessed by Meta-GGA Functionals and Random Phase Approximation. (Doctoral Dissertation). Temple University. Retrieved from http://digital.library.temple.edu/u?/p245801coll10,294630
Chicago Manual of Style (16th Edition):
Xiao, Bing. “Phase Transitions, Magnetism and Surface Adsorptions Assessed by Meta-GGA Functionals and Random Phase Approximation.” 2014. Doctoral Dissertation, Temple University. Accessed April 10, 2021.
http://digital.library.temple.edu/u?/p245801coll10,294630.
MLA Handbook (7th Edition):
Xiao, Bing. “Phase Transitions, Magnetism and Surface Adsorptions Assessed by Meta-GGA Functionals and Random Phase Approximation.” 2014. Web. 10 Apr 2021.
Vancouver:
Xiao B. Phase Transitions, Magnetism and Surface Adsorptions Assessed by Meta-GGA Functionals and Random Phase Approximation. [Internet] [Doctoral dissertation]. Temple University; 2014. [cited 2021 Apr 10].
Available from: http://digital.library.temple.edu/u?/p245801coll10,294630.
Council of Science Editors:
Xiao B. Phase Transitions, Magnetism and Surface Adsorptions Assessed by Meta-GGA Functionals and Random Phase Approximation. [Doctoral Dissertation]. Temple University; 2014. Available from: http://digital.library.temple.edu/u?/p245801coll10,294630
University of Newcastle
19.
Jayasooriya, Jayasooriya Arachchige Sachini Nisansala.
Multi-edge type density evolution: analysis, code optimization and applications to raptor code design.
Degree: PhD, 2017, University of Newcastle
URL: http://hdl.handle.net/1959.13/1343092
► Research Doctorate - Doctor of Philosophy (PhD)
The field of error correcting codes has been revolutionized by the introduction of graph-based codes, such as low-density…
(more)
▼ Research Doctorate - Doctor of Philosophy (PhD)
The field of error correcting codes has been revolutionized by the introduction of graph-based codes, such as low-density parity-check (LDPC) codes and turbo codes. These codes exhibit dramatic performance improvement with significantly lower decoding complexity over previously developed coding schemes such as Hamming codes and BCH codes, which are overwhelmingly algebraic. Since then, understanding the performance of these codes, and using this understanding to design capacity-approaching codes, is one of the utmost subjects of interest among coding specialists. This thesis adds to this field, developing analytical tools and supporting theory for designing capacity-approaching codes using the concept of multi-edge parametrization. The benefit of multi-edge parametrization is greater flexibility in code structure, which enables the specification of graphs not possible in the standard LDPC framework. The first two parts of this thesis are dedicated to developing analytical tools for graph-based codes. In the first part, we consider the design of LDPC and multi-edge type LDPC (MET-LDPC) codes, and propose an algorithm to jointly optimize the node degree distribution and the code structure of a code ensemble for given values of the maximum number of edge-types and maximum node degrees. This joint optimization is particularly important for MET-LDPC codes, because it systematically finds good MET-LDPC code structures as opposed to trial and error or intuition in conventional approaches. In the second part, we consider density evolution (DE) for LDPC and MET-LDPC codes over the binary input additive white Gaussian noise (BI-AWGN) channel. We analyze several single-parameter Gaussian approximations for DE and show that the assumption of symmetric Gaussian distribution for the DE messages is not accurate in the early decoding iterations, particularly at low rates and with punctured variable nodes. Based on these observations, we introduce a new DE approximation algorithm for LDPC and MET-LDPC codes, which is a combination of full density evolution (full-DE) and a single-parameter Gaussian approximation, where we assume a symmetric Gaussian distribution only after DE messages closely follow a symmetric Gaussian distribution. The proposed method improves the accuracy of the code threshold estimation. In addition, it significantly reduces the computational time of evaluating the code threshold compared with full-DE, thereby making it more suitable for code design. In the final part of this thesis, we employ the analytical tools designed in the first part to the problem of code design for rateless coding, in particular for Raptor codes. The main focus of this part is to analyze and design Raptor codes over a BI-AWGN channel using a multi-edge framework. We first propose a new representation of Raptor codes as MET-LDPC codes and then apply analytical tools developed in the first part of this thesis to design them. The benefit of multi-edge representation of Raptor codes is that…
Advisors/Committee Members: University of Newcastle. Faculty of Engineering & Built Environment, School of Electrical Engineering and Computing.
Subjects/Keywords: LDPC codes; MET-LDPC codes; density evolution; code optimzation; raptor codes; belief-propagation; Gaussian approximation; modulation
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Jayasooriya, J. A. S. N. (2017). Multi-edge type density evolution: analysis, code optimization and applications to raptor code design. (Doctoral Dissertation). University of Newcastle. Retrieved from http://hdl.handle.net/1959.13/1343092
Chicago Manual of Style (16th Edition):
Jayasooriya, Jayasooriya Arachchige Sachini Nisansala. “Multi-edge type density evolution: analysis, code optimization and applications to raptor code design.” 2017. Doctoral Dissertation, University of Newcastle. Accessed April 10, 2021.
http://hdl.handle.net/1959.13/1343092.
MLA Handbook (7th Edition):
Jayasooriya, Jayasooriya Arachchige Sachini Nisansala. “Multi-edge type density evolution: analysis, code optimization and applications to raptor code design.” 2017. Web. 10 Apr 2021.
Vancouver:
Jayasooriya JASN. Multi-edge type density evolution: analysis, code optimization and applications to raptor code design. [Internet] [Doctoral dissertation]. University of Newcastle; 2017. [cited 2021 Apr 10].
Available from: http://hdl.handle.net/1959.13/1343092.
Council of Science Editors:
Jayasooriya JASN. Multi-edge type density evolution: analysis, code optimization and applications to raptor code design. [Doctoral Dissertation]. University of Newcastle; 2017. Available from: http://hdl.handle.net/1959.13/1343092
Northeastern University
20.
Huang, Kuo-Lun.
Efficient algorithms for stochastic decoding of LDPC codes.
Degree: PhD, Department of Electrical and Computer Engineering, 2016, Northeastern University
URL: http://hdl.handle.net/2047/D20211572
► The expanding demand for high-speed communications has resulted in development of high-throughput error-correcting techniques required by emerging communication standards. Low-Density Parity-Check (LDPC) codes are a…
(more)
▼ The expanding demand for high-speed communications has resulted in development of high-throughput error-correcting techniques required by emerging communication standards. Low-Density Parity-Check (LDPC) codes are a class of linear block codes that achieve near-capacity performance and have been selected as part of many digital communication standards. Stochastic computation has been proposed as a hardware efficient approach for decoding LDPC codes. Using stochastic computation, all messages in the iterative decoding process are represented by Bernoulli sequences. Computations on these sequences are performed bit-by-bit using simple logic operations. Furthermore, serial messages used in stochastic decoders help alleviate routing congestion in hardware implementation of decoder. These factors make stochastic decoding a low complexity alternative to implement LDPC decoders. In this dissertation, we analyze the characteristics of stochastic decoding and propose reduced-latency designs for stochastic LDPC decoders to achieve improved performance on various channel models.; We statistically analyze the behavior of stochastic LDPC decoding, including randomization in the stochastic streams and convergence of transition probabilities in iterative decoding process. We also present a space and time-efficient code bit determination method for stochastic LDPC decoders. In addition, we investigate and characterize the decoding errors of stochastic LDPC decoders and as an example, study the stochastic-decoding-specific trapping sets in the (1056,528) LDPC code used in the WiMAX standard. This study helps to develop methods to lower the error floor of stochastic decoding.; We propose a reduced-latency stochastic decoding algorithm for LDPC codes. The proposed algorithm, called Conditional Stochastic Decoding (CSD), improves error rate performance and reduces the decoding latency by more than 30% compared with the existing stochastic decoders. We also characterize the performance of CSD in various communication schemes. For example, we show the advantages of using the proposed CSD algorithm in the Automatic Repeat reQuest (ARQ) scheme when compared with other iterative decoding algorithms.; We extend our study of stochastic decoding to non-AWGN channel models including the Binary Symmetric Channel (BSC), the Z-channel, and the Rayleigh fading channel. We introduce scaling methods to improve the performance of stochastic decoding on these channel models. On the Rayleigh fading channel, the proposed method not only reduces the computational complexity of the stochastic decoding, but also provides 3-dB improvement in performance and lowers the error floor. Simplicity of hardware implementation, low latency, and good error rate performance of the proposed schemes make them suitable for emerging communication standards.
Subjects/Keywords: low-density parity-check; stochastic computation; decoding; Decoders (Electronics); Error-correcting codes (Information theory); Coding theory; Stochastic processes; Stochastic approximation; Algorithms
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APA (6th Edition):
Huang, K. (2016). Efficient algorithms for stochastic decoding of LDPC codes. (Doctoral Dissertation). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20211572
Chicago Manual of Style (16th Edition):
Huang, Kuo-Lun. “Efficient algorithms for stochastic decoding of LDPC codes.” 2016. Doctoral Dissertation, Northeastern University. Accessed April 10, 2021.
http://hdl.handle.net/2047/D20211572.
MLA Handbook (7th Edition):
Huang, Kuo-Lun. “Efficient algorithms for stochastic decoding of LDPC codes.” 2016. Web. 10 Apr 2021.
Vancouver:
Huang K. Efficient algorithms for stochastic decoding of LDPC codes. [Internet] [Doctoral dissertation]. Northeastern University; 2016. [cited 2021 Apr 10].
Available from: http://hdl.handle.net/2047/D20211572.
Council of Science Editors:
Huang K. Efficient algorithms for stochastic decoding of LDPC codes. [Doctoral Dissertation]. Northeastern University; 2016. Available from: http://hdl.handle.net/2047/D20211572
Boston University
21.
Zhang, Liangliang.
Essays on numerical solutions to forward-backward stochastic differential equations and their applications in finance.
Degree: PhD, Mathematical Finance, 2017, Boston University
URL: http://hdl.handle.net/2144/26430
In this thesis, we provide convergent numerical solutions to non-linear forward-BSDEs (Backward Stochastic Differential Equations). Applications in mathematical finance, financial economics and financial econometrics are discussed. Numerical examples show the effectiveness of our methods.
Subjects/Keywords: Finance; FBSDE; Mollifiers; Orthogonal polynomial expansion; Portfolio choice with incomplete markets; Taylor expansion; Transition density approximation
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APA ·
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MLA ·
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APA (6th Edition):
Zhang, L. (2017). Essays on numerical solutions to forward-backward stochastic differential equations and their applications in finance. (Doctoral Dissertation). Boston University. Retrieved from http://hdl.handle.net/2144/26430
Chicago Manual of Style (16th Edition):
Zhang, Liangliang. “Essays on numerical solutions to forward-backward stochastic differential equations and their applications in finance.” 2017. Doctoral Dissertation, Boston University. Accessed April 10, 2021.
http://hdl.handle.net/2144/26430.
MLA Handbook (7th Edition):
Zhang, Liangliang. “Essays on numerical solutions to forward-backward stochastic differential equations and their applications in finance.” 2017. Web. 10 Apr 2021.
Vancouver:
Zhang L. Essays on numerical solutions to forward-backward stochastic differential equations and their applications in finance. [Internet] [Doctoral dissertation]. Boston University; 2017. [cited 2021 Apr 10].
Available from: http://hdl.handle.net/2144/26430.
Council of Science Editors:
Zhang L. Essays on numerical solutions to forward-backward stochastic differential equations and their applications in finance. [Doctoral Dissertation]. Boston University; 2017. Available from: http://hdl.handle.net/2144/26430
22.
Zang, Yishan.
Advances in Moment-Based Distributional Methodologies.
Degree: 2019, University of Western Ontario
URL: https://ir.lib.uwo.ca/etd/6304
► This thesis comprises various results that rely on the moments of a distribution or the sample moments associated with a set of observations. Since a…
(more)
▼ This thesis comprises various results that rely on the moments of a distribution or the sample moments associated with a set of observations. Since a sample of size n is uniquely specified by its first n moments, it is pertinent to make use of sample moments for modeling, classification or inference purposes. Three density mixtures are approximated by adjusting in various ways an initial density approximation referred to a base density by means certain moment-based functions, and the accuracy of the resulting density approximants are compared. A similar study is carried out in the context of density estimation. Moreover, it is explained that methodologies that are based on moments are, in fact, ideally suited to model massive data sets. Various types of quasi-Monte Carlo deterministic samples are then compared to randomly generated samples with respect to their distributional representativeness. As well, a novel methodology depending on an arctangent transformation is introduced for classifying the tail behaviour of probability laws. Finally, certain approximations to the distributions of quadratic forms in gamma, inverse Gaussian, binomial and Poisson random variables, which rely on a symbolic expansion of their moments, are proposed.
Subjects/Keywords: Density approximation; data modeling; quasi-Monte Carlo samples; classification of tail behavior; quadratic forms.; Statistical Methodology
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APA ·
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MLA ·
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APA (6th Edition):
Zang, Y. (2019). Advances in Moment-Based Distributional Methodologies. (Thesis). University of Western Ontario. Retrieved from https://ir.lib.uwo.ca/etd/6304
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Zang, Yishan. “Advances in Moment-Based Distributional Methodologies.” 2019. Thesis, University of Western Ontario. Accessed April 10, 2021.
https://ir.lib.uwo.ca/etd/6304.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zang, Yishan. “Advances in Moment-Based Distributional Methodologies.” 2019. Web. 10 Apr 2021.
Vancouver:
Zang Y. Advances in Moment-Based Distributional Methodologies. [Internet] [Thesis]. University of Western Ontario; 2019. [cited 2021 Apr 10].
Available from: https://ir.lib.uwo.ca/etd/6304.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zang Y. Advances in Moment-Based Distributional Methodologies. [Thesis]. University of Western Ontario; 2019. Available from: https://ir.lib.uwo.ca/etd/6304
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Florida
23.
Yoon, Jae Myung.
A Comparative Study of Adaptive MCMC Based Particle Filtering Methods.
Degree: MS, Mechanical Engineering - Mechanical and Aerospace Engineering, 2012, University of Florida
URL: https://ufdc.ufl.edu/UFE0044219
► In this thesis, we present a comparative study of conventional particle filtering (PF) algorithms for tracking applications. Through the review from the generic PF to…
(more)
▼ In this thesis, we present a comparative study of conventional particle filtering (PF) algorithms for tracking applications. Through the review from the generic PF to more recent Markov chain Monte Carlo (MCMC) based PFs, we will revisit the sample impoverishment problem. For all PF methods using resampling process, maintaining appropriate sample diversity is a big problem. Although Gilks et al. proposed an MCMC based PF to avoid this problem, their method sometimes fails due to small process noise. Therefore, we propose an improved MCMC move PF method which employs an adaptive MCMC move. This adaptive MCMC process elastically manages the MCMC proposal
density function to circumvent the sample impoverishment problem efficiently and gives better sample diversity for posterior
approximation. ( en )
Advisors/Committee Members: Kumar, Mrinal (committee chair), Fitz-Coy, Norman G (committee member), Barooah, Prabir (committee member).
Subjects/Keywords: Approximation; Covariance; Graphics; Kalman filters; Noise measurement; Particle density; Quantum statistics; Standard deviation; State estimation; Trajectories; filter – filtering – mcmc – particle – tracking
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APA (6th Edition):
Yoon, J. M. (2012). A Comparative Study of Adaptive MCMC Based Particle Filtering Methods. (Masters Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0044219
Chicago Manual of Style (16th Edition):
Yoon, Jae Myung. “A Comparative Study of Adaptive MCMC Based Particle Filtering Methods.” 2012. Masters Thesis, University of Florida. Accessed April 10, 2021.
https://ufdc.ufl.edu/UFE0044219.
MLA Handbook (7th Edition):
Yoon, Jae Myung. “A Comparative Study of Adaptive MCMC Based Particle Filtering Methods.” 2012. Web. 10 Apr 2021.
Vancouver:
Yoon JM. A Comparative Study of Adaptive MCMC Based Particle Filtering Methods. [Internet] [Masters thesis]. University of Florida; 2012. [cited 2021 Apr 10].
Available from: https://ufdc.ufl.edu/UFE0044219.
Council of Science Editors:
Yoon JM. A Comparative Study of Adaptive MCMC Based Particle Filtering Methods. [Masters Thesis]. University of Florida; 2012. Available from: https://ufdc.ufl.edu/UFE0044219
University of Florida
24.
Dutta, Sandipan.
Classical Representation of Quantum Systems at Equilibrium.
Degree: PhD, Physics, 2013, University of Florida
URL: https://ufdc.ufl.edu/UFE0045418
► A quantum system at equilibrium is represented by an effective classical system, chosen to reproduce thermodynamic and structural properties. The motivation is to allow application…
(more)
▼ A quantum system at equilibrium is represented by an effective classical system, chosen to reproduce thermodynamic and structural properties. The motivation is to allow application of classical strong coupling theories and classical simulations like molecular dynamics and Monte Carlo to quantum systems at strong coupling. The correspondence is made at the level of the grand canonical ensembles for the two systems. The effective classical system is defined in terms of an effective temperature, local chemical potential, and pair potential. These are determined formally by requiring the equivalence of the grand potentials and their functional derivatives of the quantum and representative classical systems. The mapping is inverted using the classical
density functional theory to solve for these three parameters. Practical forms of these formal solutions are obtained using the classical liquid state theories like hypernetted chain
approximation (HNC). The mapping is applied to the ideal Fermi gas is demonstrated and the details of the thermodynamics of the effective system is derived explicitly. As the next application we consider the uniform electron gas and an explicit form for the effective interaction potential is obtained in the weak coupling limit. The pair correlation functions are calculated using the HNC equations and compared with path integral Monte Carlo data and other theoretical models like Perrot Dharma-wardana. Excellent agreement is obtained over a wide range of temperatures and densities. The last application is to the shell structure of harmonically bound charges. We show that in the mean field limit, the quantum effects of degeneracy and diffraction produce shells at very low temperatures. ( en )
Advisors/Committee Members: Dufty, James W (committee chair), Muttalib, Khandker A (committee member), Reitze, David H (committee member), Ladd, Anthony J (committee member).
Subjects/Keywords: Approximation; Chemicals; Correlations; Effective temperature; Eggshells; Low temperature; Particle density; Pseudopotentials; Quantum field theory; Thermodynamics; dft – fluids – hnc – quantum – rpa
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APA (6th Edition):
Dutta, S. (2013). Classical Representation of Quantum Systems at Equilibrium. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0045418
Chicago Manual of Style (16th Edition):
Dutta, Sandipan. “Classical Representation of Quantum Systems at Equilibrium.” 2013. Doctoral Dissertation, University of Florida. Accessed April 10, 2021.
https://ufdc.ufl.edu/UFE0045418.
MLA Handbook (7th Edition):
Dutta, Sandipan. “Classical Representation of Quantum Systems at Equilibrium.” 2013. Web. 10 Apr 2021.
Vancouver:
Dutta S. Classical Representation of Quantum Systems at Equilibrium. [Internet] [Doctoral dissertation]. University of Florida; 2013. [cited 2021 Apr 10].
Available from: https://ufdc.ufl.edu/UFE0045418.
Council of Science Editors:
Dutta S. Classical Representation of Quantum Systems at Equilibrium. [Doctoral Dissertation]. University of Florida; 2013. Available from: https://ufdc.ufl.edu/UFE0045418
25.
Ding, Lu.
Théorie de la fonctionnelle de la densité moléculaire sous l’approximation du fluide de référence homogène : Molecular Density Functional Theory under homogeneous reference fluid approximation.
Degree: Docteur es, Chimie, 2017, Université Paris-Saclay (ComUE)
URL: http://www.theses.fr/2017SACLV004
► Les propriétés de solvatation jouent un rôle important dans les problèmes chimiques et biochimiques. La théorie fonctionnelle de la densité moléculaire (MDFT) est l'une des…
(more)
▼ Les propriétés de solvatation jouent un rôle important dans les problèmes chimiques et biochimiques. La théorie fonctionnelle de la densité moléculaire (MDFT) est l'une des méthodes frontières pour évaluer ces propriétés, dans laquelle une fonction d'énergie libre de solvatation est minimisée pour un soluté arbitraire dans une boîte de solvant cubique périodique. Dans cette thèse, nous travaillons sur l'évaluation du terme d'excès de la fonctionnelle d’énergie libre sous l’approximation du fluide de référence homogène (HRF), équivalent à l'approximation de la chaîne hypernettée (HNC) dans la théorie des équations intégrales. Deux algorithmes sont proposés: le premier est une extension d'un algorithme précédent, qui permet de traiter le cas d'un solvant moléculaire à trois dimensions (en fonction de trois angles d'Euler) au lieu d'un solvant linéaire (selon deux angles); L'autre est un nouvel algorithme qui intègre le traitement de la convolution angulaire de l'équation Ornstein-Zernike (OZ) moléculaire dans MDFT, et en fait développe la densité du solvant et le gradient fonctionnel en harmoniques sphériques généralisées (GSHs). On montre que le nouvel algorithme est beaucoup plus rapide que le précédent. Les deux algorithmes sont appropriés pour des solutés arbitraires tridimensionnel dans l'eau liquide, et pour prédire l'énergie libre et la structure de solvatation d'ions et de molécules.
Solvation properties play an important role in chemical and bio-chemical issues. The molecular density functional theory (MDFT) is one of the frontier numerical methods to evaluate these properties, in which the solvation free energy functional is minimized for an arbitrary solute in a periodic cubic solvent box. In this thesis, we work on the evaluation of the excess term of the free energy functional under the homogeneous reference fluid (HRF) approximation, which is equivalent to hypernetted-chain (HNC) approximation in integral equation theory. Two algorithms are proposed: the first one is an extension of a previously implemented algorithm, which makes it possible to handle full 3D molecular solvent (depending on three Euler angles) instead of linear solvent (depending on two angles); the other one is a new algorithm that integrates the molecular Ornstein-Zernike (OZ) equation treatment of angular convolution into MDFT, which in fact expands the solvent density and the functional gradient on generalized spherical harmonics (GSHs). It is shown that the new algorithm is much more rapid than the previous one. Both algorithms are suitable for arbitrary three-dimensional solute in liquid water, and are able to predict the solvation free energy and structure of ions and molecules.
Advisors/Committee Members: Belloni, Luc (thesis director), Borgis, Daniel (thesis director), Levesque, Maximilien (thesis director).
Subjects/Keywords: Fonctionnelle de la densité classique; Solvatation; Hypernetted-Chain; Équations intégrales; Classical density functional theory; Solvation; Hypernetted-Chain approximation; Integral equations
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APA (6th Edition):
Ding, L. (2017). Théorie de la fonctionnelle de la densité moléculaire sous l’approximation du fluide de référence homogène : Molecular Density Functional Theory under homogeneous reference fluid approximation. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2017SACLV004
Chicago Manual of Style (16th Edition):
Ding, Lu. “Théorie de la fonctionnelle de la densité moléculaire sous l’approximation du fluide de référence homogène : Molecular Density Functional Theory under homogeneous reference fluid approximation.” 2017. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed April 10, 2021.
http://www.theses.fr/2017SACLV004.
MLA Handbook (7th Edition):
Ding, Lu. “Théorie de la fonctionnelle de la densité moléculaire sous l’approximation du fluide de référence homogène : Molecular Density Functional Theory under homogeneous reference fluid approximation.” 2017. Web. 10 Apr 2021.
Vancouver:
Ding L. Théorie de la fonctionnelle de la densité moléculaire sous l’approximation du fluide de référence homogène : Molecular Density Functional Theory under homogeneous reference fluid approximation. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2017. [cited 2021 Apr 10].
Available from: http://www.theses.fr/2017SACLV004.
Council of Science Editors:
Ding L. Théorie de la fonctionnelle de la densité moléculaire sous l’approximation du fluide de référence homogène : Molecular Density Functional Theory under homogeneous reference fluid approximation. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2017. Available from: http://www.theses.fr/2017SACLV004
University of Florida
26.
Verma,Prakash.
Increasing the Applicability of Density Functional Theory.
Degree: PhD, Chemistry, 2011, University of Florida
URL: https://ufdc.ufl.edu/UFE0042848
► According to density functional theory(DFT), the density is a sufficient variable for the description of degenerate or non-degenerate ground state of molecules. The density is…
(more)
▼ According to
density functional theory(DFT), the
density is a sufficient variable for the description of degenerate or non-degenerate ground state of molecules. The
density is generally obtained by solving the self-consistent Kohn-Sham (KS) equations rather than by direct minimization of the energy. An attractive feature that the KS procedure offers is it provides a pictorial molecular orbital view of the molecules and the electronic spectra in terms of the KS orbitals. Besides their role in frontier molecular orbital theory
Advisors/Committee Members: Bartlett, Rodney J (committee chair), Reynolds, John R (committee member), Deumens, Erik (committee member), Ohrn, Nils Y (committee member), Biswas, Amlan (committee member).
Subjects/Keywords: Approximation; Density functional theory; Eigenvalues; Electrons; Energy; Flux density; Ion density; Ionization; Orbitals; Particle density; bartlett – dft – non – oep – rpa
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APA (6th Edition):
Verma,Prakash. (2011). Increasing the Applicability of Density Functional Theory. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0042848
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Chicago Manual of Style (16th Edition):
Verma,Prakash. “Increasing the Applicability of Density Functional Theory.” 2011. Doctoral Dissertation, University of Florida. Accessed April 10, 2021.
https://ufdc.ufl.edu/UFE0042848.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
MLA Handbook (7th Edition):
Verma,Prakash. “Increasing the Applicability of Density Functional Theory.” 2011. Web. 10 Apr 2021.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Vancouver:
Verma,Prakash. Increasing the Applicability of Density Functional Theory. [Internet] [Doctoral dissertation]. University of Florida; 2011. [cited 2021 Apr 10].
Available from: https://ufdc.ufl.edu/UFE0042848.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Council of Science Editors:
Verma,Prakash. Increasing the Applicability of Density Functional Theory. [Doctoral Dissertation]. University of Florida; 2011. Available from: https://ufdc.ufl.edu/UFE0042848
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
University of Illinois – Urbana-Champaign
27.
Ning, Zhenhua.
TDDFT calculations for excitation spectra of solids and superstructures utilizing mGGA.
Degree: PhD, Physics, 2015, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/78357
► The first principles study plays a very important role in developing new generation of materials, such as organic semiconductors and long polymer chains, as well…
(more)
▼ The first principles study plays a very important role in developing new generation of materials, such
as organic semiconductors and long polymer chains, as well as understanding of physical properties of
nanoparticles , inorganic semiconductors and semiconductor alloys. In this work, we start from the Kohn-Sham one-particle equation Schr¨odinger equation and solve it by expanding its eigenfunctions in terms of the linear augmented-slater-type orbits(LASTO) under full potential with the exchange-correlation potential
functional given by meta-generalized gradient
approximation(mGGA). Our theoretical results were compared
to WIEN2K’s, and good agreement was obtained. As the application, we apply TDDFT plus mGGA to
calculate optical spectra for bulk solids. The result shows good agreement with experimental data.
III-V ternary alloys AxB1−xC are promising materials for optoelectronic, high-speed electronic and
microwave applications, such as infrared emitting diodes and detectors, high electron mobility transistors,
heterojunction bipolar transistors, quantum-dot lasers, modulators and ultrafast switches. We adopted
the TDDFT theory and the cluster averaging method to compute the spectra of III-V ternary alloys with
arbitrary concentration x. We find great agreement between theoretical and experimental data. The success
of this method is mainly because that we approximate the transition matrix elements by the LDA p-matrix
elements via (mGGA) which contains the singularity of the type fXC,00(q) ∼ 1/q2 as q → 0. Thus, Our
studies provide some insight into the theoretical calculation of optical spectra of semiconductor alloys.
Advisors/Committee Members: Chang, Yia-Chung (advisor), Stack, John D. (Committee Chair), Schleife, Andre (committee member), Hubler, Alfred W. (committee member).
Subjects/Keywords: Time-dependent Density Functional Theory (TDDFT); semiconductor; semiconductor alloys; optical spectrum; Linearized Augmented Slater-type Orbital (LASTO); meta-generalized gradient approximation (mGGA); Local Density Approximation (LDA); cluster averaging method; Kohn-Sham; exchange-correlation potential; transition matrix element
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APA (6th Edition):
Ning, Z. (2015). TDDFT calculations for excitation spectra of solids and superstructures utilizing mGGA. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/78357
Chicago Manual of Style (16th Edition):
Ning, Zhenhua. “TDDFT calculations for excitation spectra of solids and superstructures utilizing mGGA.” 2015. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed April 10, 2021.
http://hdl.handle.net/2142/78357.
MLA Handbook (7th Edition):
Ning, Zhenhua. “TDDFT calculations for excitation spectra of solids and superstructures utilizing mGGA.” 2015. Web. 10 Apr 2021.
Vancouver:
Ning Z. TDDFT calculations for excitation spectra of solids and superstructures utilizing mGGA. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2015. [cited 2021 Apr 10].
Available from: http://hdl.handle.net/2142/78357.
Council of Science Editors:
Ning Z. TDDFT calculations for excitation spectra of solids and superstructures utilizing mGGA. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2015. Available from: http://hdl.handle.net/2142/78357
28.
Gebresilassie, Abel Gebreegziabher.
Atomic scale simulations in zirconia : Effect of yttria doping and environment on stability of phases : Modélisation atomistique dans la zircone : Rôle du dopage par l'yttrium et de l'environnement sur la stabilité des différences phases.
Degree: Docteur es, Génie des matériaux, 2016, Lyon
URL: http://www.theses.fr/2016LYSEI038
► Ce travail de thèse est une étude par des méthodes de simulation de structure électronique du phénomène de dégradation en milieu aqueux de la zircone…
(more)
▼ Ce travail de thèse est une étude par des méthodes de simulation de structure électronique du phénomène de dégradation en milieu aqueux de la zircone yttriée. La zircone yttriée est notamment utilisée pour la fabrication de prothèses dont la durée de vie dépend du matériau et de son environnement. Pour ces applications, la zircone yttriée est de structure tétragone, mais en fonction du dopage en yttrium et de l'environnement, cette phase est en compétition avec des structures monoclinique et cubique. Cette compétition est cruciale dans ce travail car elle peut à la fois, augmenter la résistance, ou favoriser la détérioration de ce matériau. L'étude réalisée se concentre sur des taux de dopage inférieurs à 20% mol. en oxyde d'yttrium Y2O3.Dans un premier temps, les structures atomiques d'équilibre à basse température ont été déterminées dans les trois phases en utilisant une méthode de calcul basée sur la Théorie de la Fonctionnelle de la Densité, dans l'approximation de la densité locale. Les résultats incluent de nouvelles structures qui n'ont jusqu'alors pas été discutées dans la littérature et qui sont cohérentes avec le diagramme de phase de la zircone yttriée à basse température. Une analyse plus détaillée suggère que le mécanisme de stabilisation de la zircone yttriée tetragonale est un effet du dépistage ionocovalent particulièrement efficace dans cette phase et dont la signature dans la structure s'exprime par la présence d'ions zirconium en coordination 7. Ceci représente un point important permettant de lier stabilité et structure dans ces systèmes. Une deuxième partie de ce travail est consacrée à l’effet de l'eau dans la zircone yttriée en volume. Pour conclure, ce manuscrit représente une contribution originale à la compréhension de mécanismes à l'échelle atomique qui sont à l'origine des propriétés de la zircone yttriée et de ses applications.yttriée et de ses applications.
This PhD thesis is an electronic structure simulation work to study the stabilization mechanism of yttria stabilized zirconia (YSZ) and the phenomena of the degradation of YSZ due to the presence of an aqueous media. YSZ is used especially in dental and orthopedics application sbut its service depends on the environment. For these biomedical applications a crystallographic tetragonal YSZ (t-YSZ) structure is used, but depending on the concentration of yttria (Y2O3) and the environment, this tetragonal structure is thermodynamically in competition with a monoclinic and cubic phases. This competition is crucial in this work, because it has both effects : increase the resistance or promote the degradation of this material. The study is conducted for Y2O3 concentrations less than 20% mol. First, atomic structures of the three phases at low temperature were determined using density functional theory (DFT)with the local density approximations (LDA). The results include new structures that were not discussed in the literature and which are consistent with the phase diagram of YSZ at low temperature. A more detailed analysis suggests that…
Advisors/Committee Members: Chevalier, Jérôme (thesis director), Gremillard, Laurent (thesis director).
Subjects/Keywords: Zircone yttriée stabilisée; Structure atomique; Taux de dopage; Méthode fonctionnelle densité; Approximation densité locale; Dégradation à basse température; Dégradation en milieu aqueux; Milieu aqueux; YSZ - Yttria Stabilized Zirconia; Atomic structure; Doping rate; DFT - Density Functional Theory; LDA - Local Density Approximation; Low Temperature Degradation; Aqueous medium; 620.143 072
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APA ·
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APA (6th Edition):
Gebresilassie, A. G. (2016). Atomic scale simulations in zirconia : Effect of yttria doping and environment on stability of phases : Modélisation atomistique dans la zircone : Rôle du dopage par l'yttrium et de l'environnement sur la stabilité des différences phases. (Doctoral Dissertation). Lyon. Retrieved from http://www.theses.fr/2016LYSEI038
Chicago Manual of Style (16th Edition):
Gebresilassie, Abel Gebreegziabher. “Atomic scale simulations in zirconia : Effect of yttria doping and environment on stability of phases : Modélisation atomistique dans la zircone : Rôle du dopage par l'yttrium et de l'environnement sur la stabilité des différences phases.” 2016. Doctoral Dissertation, Lyon. Accessed April 10, 2021.
http://www.theses.fr/2016LYSEI038.
MLA Handbook (7th Edition):
Gebresilassie, Abel Gebreegziabher. “Atomic scale simulations in zirconia : Effect of yttria doping and environment on stability of phases : Modélisation atomistique dans la zircone : Rôle du dopage par l'yttrium et de l'environnement sur la stabilité des différences phases.” 2016. Web. 10 Apr 2021.
Vancouver:
Gebresilassie AG. Atomic scale simulations in zirconia : Effect of yttria doping and environment on stability of phases : Modélisation atomistique dans la zircone : Rôle du dopage par l'yttrium et de l'environnement sur la stabilité des différences phases. [Internet] [Doctoral dissertation]. Lyon; 2016. [cited 2021 Apr 10].
Available from: http://www.theses.fr/2016LYSEI038.
Council of Science Editors:
Gebresilassie AG. Atomic scale simulations in zirconia : Effect of yttria doping and environment on stability of phases : Modélisation atomistique dans la zircone : Rôle du dopage par l'yttrium et de l'environnement sur la stabilité des différences phases. [Doctoral Dissertation]. Lyon; 2016. Available from: http://www.theses.fr/2016LYSEI038
29.
Lončar Sanja.
Negative Selection - An Absolute Measure of Arbitrary Algorithmic Order Execution.
Degree: 2017, University of Novi Sad
URL: https://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija149968375076346.pdf?controlNumber=(BISIS)104861&fileName=149968375076346.pdf&id=10182&source=OATD&language=en
;
https://www.cris.uns.ac.rs/record.jsf?recordId=104861&source=OATD&language=en
► Algorithmic trading is an automated process of order execution on electronic stock markets. It can be applied to a broad range of financial instruments,…
(more)
▼ Algorithmic trading is an automated process of order execution on electronic stock markets. It can be applied to a broad range of financial instruments, and it is characterized by a signicant investors' control over the execution of his/her orders, with the principal goal of finding the right balance between costs and risk of not (fully) executing an order. As the measurement of execution performance gives information whether best execution is achieved, a signicant number of diffeerent benchmarks is used in practice. The most frequently used are price benchmarks, where some of them are determined before trading (Pre-trade benchmarks), some during the trading day (In-traday benchmarks), and some are determined after the trade (Post-trade benchmarks). The two most dominant are VWAP and Arrival Price, which is along with other pre-trade price benchmarks known as the Implementation Shortfall (IS). We introduce Negative Selection as a posteriori measure of the execution algorithm performance. It is based on the concept of Optimal Placement, which represents the ideal order that could be executed in a given time win-dow, where the notion of ideal means that it is an order with the best execution price considering market conditions during the time window. Negative Selection is dened as a difference between vectors of optimal and executed orders, with vectors dened as a quantity of shares at specied price positionsin the order book. It is equal to zero when the order is optimally executed; negative if the order is not (completely) filled, and positive if the order is executed but at an unfavorable price. Negative Selection is based on the idea to offer a new, alternative performance measure, which will enable us to find the optimal trajectories and construct optimal execution of an order. The first chapter of the thesis includes a list of notation and an overview of denitions and theorems that will be used further in the thesis. Chapters 2 and 3 follow with a theoretical overview of concepts related to market microstructure, basic information regarding benchmarks, and theoretical background of algorithmic trading. Original results are presented in chapters 4 and 5. Chapter 4 includes a construction of optimal placement, definition and properties of Negative Selection. The results regarding the properties of a Negative Selection are given in [35]. Chapter 5 contains the theoretical background for stochastic optimization, a model of the optimal execution formulated as a stochastic optimization problem with regard to Negative Selection, as well as original work on nonmonotone line search method [31], while numerical results are in the last, 6th chapter.
Algoritamsko trgovanje je automatizovani proces izvršavanja naloga na elektronskim berzama. Može se primeniti na širok spektar nansijskih instrumenata kojima se trguje na berzi i karakteriše ga značajna kontrola investitora nad izvršavanjem njegovih naloga, pri čemu se…
Advisors/Committee Members: Krejić Nataša, Lužanin Zorana, Rajter-Ćirić Danijela, Urošević Branko.
Subjects/Keywords: Nonlinear optimization, stochastic optimization - Sample Average Approximation, nonmonotone line search, zero upper density convergence, algorithmic trading, performance measure; Nelinearna optimizacija, stohastička optimizacija - Sample Average Approximation metod, nemonotono linijsko pretraživanje, konvergencija "zero upper density", algoritamsko trgovanje, mera performansi
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APA ·
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APA (6th Edition):
Sanja, L. (2017). Negative Selection - An Absolute Measure of Arbitrary Algorithmic Order Execution. (Thesis). University of Novi Sad. Retrieved from https://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija149968375076346.pdf?controlNumber=(BISIS)104861&fileName=149968375076346.pdf&id=10182&source=OATD&language=en ; https://www.cris.uns.ac.rs/record.jsf?recordId=104861&source=OATD&language=en
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sanja, Lončar. “Negative Selection - An Absolute Measure of Arbitrary Algorithmic Order Execution.” 2017. Thesis, University of Novi Sad. Accessed April 10, 2021.
https://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija149968375076346.pdf?controlNumber=(BISIS)104861&fileName=149968375076346.pdf&id=10182&source=OATD&language=en ; https://www.cris.uns.ac.rs/record.jsf?recordId=104861&source=OATD&language=en.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sanja, Lončar. “Negative Selection - An Absolute Measure of Arbitrary Algorithmic Order Execution.” 2017. Web. 10 Apr 2021.
Vancouver:
Sanja L. Negative Selection - An Absolute Measure of Arbitrary Algorithmic Order Execution. [Internet] [Thesis]. University of Novi Sad; 2017. [cited 2021 Apr 10].
Available from: https://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija149968375076346.pdf?controlNumber=(BISIS)104861&fileName=149968375076346.pdf&id=10182&source=OATD&language=en ; https://www.cris.uns.ac.rs/record.jsf?recordId=104861&source=OATD&language=en.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sanja L. Negative Selection - An Absolute Measure of Arbitrary Algorithmic Order Execution. [Thesis]. University of Novi Sad; 2017. Available from: https://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija149968375076346.pdf?controlNumber=(BISIS)104861&fileName=149968375076346.pdf&id=10182&source=OATD&language=en ; https://www.cris.uns.ac.rs/record.jsf?recordId=104861&source=OATD&language=en
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Florida
30.
Smith, Jack A., 1949- ( Dissertant ).
A Projected Hamiltonian approach to polyatomic systems.
Degree: 1978, University of Florida
URL: https://ufdc.ufl.edu/UF00099255
A method of treating polyatomic systems, finite or
Subjects/Keywords: Approximation; Atomic spectra; Atoms; Charge density; Chemical valence; Flux density; Ion density; Modeling; Nickel; Oxides; Binding energy; Chemistry thesis Ph. D; Hartree-Fock approximation
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APA (6th Edition):
Smith, Jack A., 1. (. D. ). (1978). A Projected Hamiltonian approach to polyatomic systems. (Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UF00099255
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Smith, Jack A., 1949- ( Dissertant ). “A Projected Hamiltonian approach to polyatomic systems.” 1978. Thesis, University of Florida. Accessed April 10, 2021.
https://ufdc.ufl.edu/UF00099255.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Smith, Jack A., 1949- ( Dissertant ). “A Projected Hamiltonian approach to polyatomic systems.” 1978. Web. 10 Apr 2021.
Vancouver:
Smith, Jack A. 1(D). A Projected Hamiltonian approach to polyatomic systems. [Internet] [Thesis]. University of Florida; 1978. [cited 2021 Apr 10].
Available from: https://ufdc.ufl.edu/UF00099255.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Smith, Jack A. 1(D). A Projected Hamiltonian approach to polyatomic systems. [Thesis]. University of Florida; 1978. Available from: https://ufdc.ufl.edu/UF00099255
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
◁ [1] [2] [3] [4] ▶
. 
Open Access Theses and Dissertations
