Дисертації з теми "Dual-factor"
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Bourke, Patrick Anthony. "A general factor in dual task performance decrement." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359419.
Повний текст джерелаSlobodchikoff, Tatyana G. "The Slavic Dual: Morphosyntactic Feature Economy as a Factor in Language Change." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/297021.
Повний текст джерелаMcKay, Brock L. (Brock Lindsay). "Dual Factor Socially Desirable Responding and Contrasts in Intrinsic and Extrinsic Religious Motivation." Thesis, University of North Texas, 1994. https://digital.library.unt.edu/ark:/67531/metadc278762/.
Повний текст джерелаOest, Megan Elizabeth. "Dual Osteogenic and Angiogenic Growth Factor Delivery as a Treatment for Segmental Bone Defects." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16264.
Повний текст джерелаHu, Jing. "Targeting Transcription Factor NF-kappa B by Dual Functional Oligodeoxynucleotide Complex for Inhibition of Neuroinflammation." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439301618.
Повний текст джерелаSarnoff, Tamar Jill. "METAPHOR, COGNITIVE ELABORATION AND PERSUASION." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194626.
Повний текст джерелаOgino, Shuichi. "Efficacy of the dual controlled release of HGF and bFGF impregnated with a collagen/gelatin scaffold." Kyoto University, 2018. http://hdl.handle.net/2433/231010.
Повний текст джерелаThalji, Amanda Lynn. "A Dual-Factor Model of Mental Health in High School Students: Group Characteristics and Social Functioning." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4239.
Повний текст джерелаEbisine, Kimimuepigha. "Dual regulation of transcription factor Nrf2 by Keap1 and the beta-TrCP/GSK-3 in cancer." Thesis, University of Dundee, 2019. https://discovery.dundee.ac.uk/en/studentTheses/20338051-4e92-417e-aeb1-4cd3dc86eda4.
Повний текст джерелаYehya, Alaa. "New insights into Brain-derived Neurotrophic Factor Dual Signaling : imbalance implications in mechanisms of neuroprotection and neurotoxicity." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS058.
Повний текст джерелаBrain-derived neurotrophic factor (BDNF) is the most abundant secreted and widely distributed neurotrophin in human brain. It has been extensively studied for its role in neuronal survival, growth and synaptic plasticity. BDNF signaling mediated through tryosine receptor kinase B (TrkB) and p75NTR neurotrophin receptor (p75NTR). It is well established that BDNF beneficial actions are mediated by it is high-affinity TrkB, whereas pro-BDNF activates p75NTR towards apoptosis. This diverse dual signaling is normally under a tight balance regulation. Based on clinical and animal studies, it has been suggested that BDNF signaling is involved in tauopathy, which is a pathological hallmark in several neurodegenerative diseases, including Alzheimer's disease (AD). However, what changes tauopathy may induce on BDNF signaling, and whether BDNF deregulation could affect its two signaling receptors (TrkB, p75NTR), and eventually tauopathy pathogenesis, have not been investigated. In this study we used a transgenic zebrafish line for human Tau-P301L tauopathy, and measured transcriptional and protein levels of BDNF and of its two signaling receptors. We found no modification of BDNF and TrkB expression levels, but a significant up-regulation of p75NTR. We then used the same transgenic line to generate BDNF knockdown using morpholino microinjection technique. Interestingly, BDNF knockdown differentially affects TrkB and p75NTR; we observed a reduction of TrkB expression and an increase in p75NTR expression. In addition, BDNF knockdown aggravates tauopathy-associated toxicity; we found an increase in neuronal cell death and tau hyperphosphorylation, the latter was accompanied by an activation of tau glycogen synthase kinase 3beta (GSK3beta). Attenuation of BDNF neuroprotective effects through imbalance of its signaling receptors was further highlighted through studying BDNF role in the development of zebrafish posterior lateral line system (PLL). This system has recently emerged as a powerful tool to study several dynamic biological processes, including collective cell migration and nerve/hair cells regeneration. We detected BDNF expression in different PLL components. BDNF knockdown led to an impairment of the PLL primordium migration due to concomitant increase in cell death rate. In addition, reduced cell proliferation and defect in axonal re-growth were observed , which led to major defects of PLL nerve/hair cells regeneration, respectively. These findings suggest that BDNF has an essential role in PLL development, but more important they introduce PLL as research model to study BDNF functions. This is the first study to provide a detailed in vivo analysis of BDNF and its two signaling receptors. Our findings highlight several implications of BDNF signaling deregulation. Balanced signaling clearly has essential roles in survival and development, in addition to being a therapeutic target, BDNF can itself activate diverse molecular pathways, thus setting up a potential circuitry that could enhance its protective role
Thalji, Amanda L. "Predicting Early Adolescents’ Academic Achievement and In-School Behavior with a Dual-Factor Model of Mental Health." Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1787.
Повний текст джерелаShaffer, Emily J. "An investigation of a dual-factor model of mental health and related physical health outcomes among early adolescents." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001757.
Повний текст джерелаBrown, Serena Jean Silver. "Dual functions of the retinal determination gene network member EYES ABSENT as a transcription factor and protein phosphatase." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/33454.
Повний текст джерелаLind, Joakim, and Lars Sparre. "Investigating New Multifactor Models with a Conditional Dual-Beta : Can a Conditional Dual-Beta in the Market Factor add Explanatory Value in New Multifactor Models? A study of the Swedish Stock Market between 2003 and 2015." Thesis, Linköpings universitet, Företagsekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129987.
Повний текст джерелаKauer, Michaela [Verfasser], Ralph [Akademischer Betreuer] Bruder, and Joachim [Akademischer Betreuer] Vogt. "Identification as Determining Factor of Technology Acceptance for Hedonic and Dual Use Products / Michaela Kauer. Betreuer: Ralph Bruder ; Joachim Vogt." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2012. http://d-nb.info/1106117921/34.
Повний текст джерелаNaples, Lauren Hunter. "Neurodivergence in Early Childhood| Deriving a Dual-Factor Model of Educational Well-Being Through a Design-Based Research Pilot Program." Thesis, The George Washington University, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13813592.
Повний текст джерелаThere is a distinct need to understand subjective well-being for neurodivergent students in early childhood. Review of previous literature suggests the positive influence of subjective well-being in mitigating psychological distress; however, young children have been excluded from these investigations. Therefore, this study employed an advanced mixed methods research design, through which a convergent core was embedded within an overarching quasi-experimental framework to analyze three key outcomes in early childhood education: (a) self-identified conceptualizations of student covitality, (b) self-evaluated levels of student covitality, and (c) teacher-rated levels of executive dysfunction.
All students actively enrolled in a local partner school serving pre-Kindergarten to 2nd grade (N = 45) participated in qualitative and quantitative evaluations of covitality. Qualitative data were collected through semi-structured focus groups, and quantitative data were collected through student ratings on the Social-Emotional Health Survey-Primary (Furlong, You, Renshaw, O’Malley, & Rebelez, 2013). Qualitative findings suggested students conceptualize covitality as positive school experiences along a developmental trajectory across five themes—play activities, classroom instruction, school environmental factors, interpersonal relationships, and special programs. Quantitative results determined excellent internal reliability of the covitality scale for early elementary 1st- and 2nd-grade students (Cronbach's α = .908).
Two classrooms were randomly assigned to the waitlist control ( n = 14) or intervention (n = 10) condition—1st- and 2nd-grade, respectively. A novel positive psychology intervention was designed and tested to promote covitality. Implementation of strategically targeted practices supported the underlying factors of gratitude, zest, optimism, and persistence.
Additional quantitative data were collected through teacher ratings of cognition on the Behavior Rating Inventory of Executive Function, Second Edition (Gioia, Isquith, Guy, & Kenworthy, 2016). Intervention effects indicated a statistically significant interaction for improved executive functioning relative to the waitlist control group (p = .011). Integration of qualitative and quantitative results produced preliminary evidence of categorical advancement in a dual-factor clinical classification system and distinctions in varied and nuanced conceptualizations of well-being constructs over time. Synthesis of qualitative, quantitative, and integrated findings highlighted the value of design-based research generally, and the Student Strengths Safari© program, specifically, to establish a dual-factor model of educational well-being (EdWB) for optimal student development.
Smith, Nicholas David W. "An Application of the Dual Factor Model of Mental Health in Elementary School Students: Implications for Social Functioning and Psychopathology." Scholar Commons, 2018. http://scholarcommons.usf.edu/etd/7231.
Повний текст джерелаFrank, Michael James. "Youth Character Strengths, Peer Victimization, and Well-Being: Understanding Associations between Positive Traits, Social Experiences, and Positive Psychological Outcomes." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5481.
Повний текст джерелаJadlowsky, Julie Kendal. "Dual Control of HIV Transcription Elongation: Virus-Specific Negative Control by NELF-E is Counterbalanced by Positive Transcription Factor P-TEFb." Case Western Reserve University School of Graduate Studies / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1228234927.
Повний текст джерелаJadlowsky, Julie Kendal. "Dual control of HIV transcription elongation virus-specific negative control by NELF-E is counterbalanced by positive transcription factor P-TEFb /." Cleveland, Ohio : Case Western Reserve University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=case1228234927.
Повний текст джерелаCook, Peter Joseph. "Eya a dual function nuclear factor crucial for regulation of developmental gene expression and prevention of apoptosis in response to genotoxic stress /." Diss., [La Jolla, Calif.] : University of California, San Diego, 2009. http://wwwlib.umi.com/cr/ucsd/fullcit?p3344509.
Повний текст джерелаTitle from first page of PDF file (viewed March 13, 2009). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
Beltrame, Fernando. "Análise comparativa de conversores monofásicos aplicados a correção de fator de potência." Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/8473.
Повний текст джерелаEsse trabalho apresenta um estudo e uma análise comparativa de conversores monofásicos aplicados i correção de fator de potência que estejam de acordo com as normas internacionais IEC 61000-3-4 (limitação de harmônicos) e CISPR 22 (limitação dos níveis de interferência eletromagnética) para aplicações de alta potência. Os conversores estudados foram os conversores Boost, o conversor Boost Intercalado, com duas células operando com uma defasagem de 180" entre si, e o conversor Dual Boost. Tais conversores são utilizados como estágio de entrada em fontes de equipamentos da tecnologia da informação. Todos os conversores apresentam a mesma tensão de entrada e saída, e a mesma corrente de entrada. Os conversores foram projetados para apresentarem a mesma taxa de distorção harmônica da corrente de entrada (THD) para que, dessa forma, todos tenham o mesmo filtro de entrada. A implementação das leis de controle foi realizada através de um controlador digital com o uso de um microcontrolador de 16 bits. Todos os conversores foram primeiramente estudados e são apresentados nesta dissertação. Os parâmetros analisados para a comparação das topologias foram: fator de potência, taxa de distorção harmônica, perdas nos dispositivos semicondutores e magnéticos, volume dos dissipadores e materiais magnéticos, interferência eletromagnética conduzida, eficiência e custos.
Mcmahan, Melanie M. "A Longitudinal Examination of High School Students' Group Membership in a Dual-Factor Model of Mental Health: Stability of Mental Health Status and Predictors of Change." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4369.
Повний текст джерелаBirchenough, Holly. "Investigation of the tumour necrosis factor-stimulated gene-6 (TSG-6) interactome : use and development of surface sensitive techniques." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/investigation-of-the-tumour-necrosis-factorstimulated-gene6-tsg6-interactome-use-and-development-of-surface-sensitive-techniques(4866db6a-fd8e-4831-babb-b4d3c11307e3).html.
Повний текст джерелаSpringer, Sheila, and Sheila Springer. "Effects of Media Use on Bereavement." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/626158.
Повний текст джерелаEslami, Aida. "Analyse factorielle de données structurées en groupes d'individus : application en biologie." Thesis, Rennes 1, 2013. http://www.theses.fr/2013REN1S091.
Повний текст джерелаThis work deals with multi-group analysis, to study multi-group data where individuals are a priori structured into different groups. The thesis tackles the issue of multi-group data in a multivariate, multi-block, three-way and two-block (regression) setting. It presents several methods of multi-group data analysis in the framework of factorial analysis. It includes three sections. The first section concerns the case of multivariate multi-group data. The aim is either descriptive (within-group analysis) or predictive (discriminant analysis, between-group analysis). We start with a comprehensive review of multi-group methods. Furthermore, we propose two methods namely Dual Generalized Procrustes Analysis and Dual Common Component and Specific Weights Analysis. We also exhibit new properties and algorithms for multi-group Principal Component Analysis. The second section deals with multiblock multi-group and three-way multi-group data analysis. We give a general review of multiblock multi-group methods. In addition, we propose two methods, namely multiblock and multi-group PCA and Weighted-multiblock and multi-group PCA, as extensions of multi-group Principal Component Analysis. The two-block multi-group analysis is taken into account in the third section. Firstly, we give a presentation of appropriate methods to investigate the relationship between an explanatory dataset and a dependent dataset where there is a group structure among individuals. Thereafter, we propose four methods, namely multi-group PLS, in the PLS approach, and among them we select one and develop it into a regression strategy. The proposed methods are illustrated on the basis of several real datasets in the field of biology. All the strategies of analysis are implemented within the framework of R
Sun, Peng. "Semiparametric Bayesian Approach using Weighted Dirichlet Process Mixture For Finance Statistical Models." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/78189.
Повний текст джерелаPatterson, Jennifer. "Nurse Supervisors and Certified Nursing Assistants: Leadership Characteristics and Job Satisfaction." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5583.
Повний текст джерелаLui, Yuan Siang. "Developing sustained dual-drug therapy for tendon sports injuries." Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/23739.
Повний текст джерелаBerberovic, Adnan, and Alexander Eriksson. "A Multi-Factor Stock Market Model with Regime-Switches, Student's T Margins, and Copula Dependencies." Thesis, Linköpings universitet, Produktionsekonomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-143715.
Повний текст джерелаValtinson, Gale Rene. "A multi-sample confirmatory factor analysis of work-family conflict." Virtual Press, 1998. http://liblink.bsu.edu/uhtbin/catkey/1115719.
Повний текст джерелаDepartment of Counseling Psychology and Guidance Services
Hilton, Traci Leigh. "Dual function of TAF1 in basal and activated cyclin D1 transcription /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/6275.
Повний текст джерелаLim, Mook Tzeng. "Hydrodynamics of a Cold Model of a Dual Fluidized Bed Gasification Plant." Thesis, University of Canterbury. Chemical and Process Engineering, 2012. http://hdl.handle.net/10092/6287.
Повний текст джерелаMalik, Naveed ur Rehman. "Modelling, Analysis, and Control Aspects of a Rotating Power Electronic Brushless Doubly-Fed Induction Generator." Doctoral thesis, KTH, Elektrisk energiomvandling, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-174349.
Повний текст джерелаQC 20151006
Kzam, Aref Kalilo Lima. "Formulação dual em mecânica da fratura utilizando elementos de contorno curvos de ordem qualquer." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-03032010-083004/.
Повний текст джерелаThis work presents the dual boundary element formulation applied to linear crack problem. The goal of this research is the evaluation of stress intensity factor for two-dimensional crack problem using three different techniques, which are: the technique of correlation of displacements, the technique based on the state of tension at the crack tip and J integral. The analysis is performed using the computational code developed during the research, which incorporates the direct formulations related to displacement and traction boundary element equation. A greater emphasis is given to the use of curved boundary element of any order. In the dual boundary element method the singular integral equations with singular others O(\'R POT.-1\') and O(\'R POT.-2\') are assessed satisfactorily with the application of the singularity subtraction method. The results of these singular integrals are evaluated by the Cauchy Principal Value and the Hadamard Finite Part. The code developed is compared with the analytical solutions found in the literature including the analysis of solids with fractures default and evaluation of stress intensity factor, which produced good results.
Marzouk, Mounir. "Développement de chargeurs intégrés pour véhicules hybrides plug-in." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT088/document.
Повний текст джерелаThis thesis consists on the design and realization of a plug-in hybrid vehicle integrated tractiondrive supply. The work turns to a solution of a mutualized converter, in the objective to imagine asolution which shared drive and battery chargers modes, the three-level NPC topology has beenretained. The single phase charger is based on an interleaved PWM rectifier, and motor windings areused as smoothing inductors. A double-boost PFC configuration is introduced to ensure the threephasecharger. Passives are sized in each configuration in order to take in account the whole currentconstraints (LF and HF). The PFC behavior is based on the resonant controllers. Then, a 5 kWprototype has been realized to validate the different application modes.In a second part, a single-stage isolated charger based on a Dual-Active-Bridge (DAB) isproposed. The topology is modeled to the fundamental and the PFC control law is studied. A threephaseconfiguration is simulated in order to achieve higher charging powers and to reduce batterycurrent low-frequency ripple
Hyde, Robert Harry. "Growth and Characterization of Thermoelectric Ba8Ga16Ge30 Type-I Clathrate Thin-Films Deposited by Pulsed Dual-Laser Ablation." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3162.
Повний текст джерелаBen, Jazia Abderrahim. "Flexible public private partnerships : a real-option-based optimization approach." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0176/document.
Повний текст джерелаPublic private partnerships can be a solution to the dilemma of how to do more with less available funds that public entities are constantly financing in the last decades. If implemented properly, Public Private Partnerships can contribute to the modernization of public service provision and can constitute efficient vehicles for the delivery of optimal value for money. The high incidence of renegotiation as well as the difficulty of accurately predicting the future demand on the projects is a matter of concern when it comes to the financial structuring of Public Private Partnerships. This work proposes a real-option- based optimization framework to boost the financial viability of the projects. This is done by introducing flexible financial clauses. First, an adequate framework for risk management, where volatility is derived by Monte Carlo simulation and the valuation is made without switching to the risk neutral measure, is presented. Four families of flexible clauses are, afterwards, investigated. Such clauses are triggerred, if the revenue level of the projet is not sufficient to guarnatee its financiel viability. Finally, this work develops a multi-objective optimization approach in order to assess the different trade-offs that the introduction of flexibility leads to. The proposed optimization problem is solved via multi-objective evolutionary algorithms
Підгурська, Тетяна Вікторівна. "Двосмугові фільтри на діелектричних резонаторах з вищими типами коливань". Doctoral thesis, Київ, 2016. https://ela.kpi.ua/handle/123456789/15382.
Повний текст джерелаLin, Yen-ting, and 林彥廷. "Study and Implementation of a Dual-mode Power Factor Correct." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/01818393471856188350.
Повний текст джерела國立臺灣科技大學
電子工程系
98
This thesis aims to study a dual-mode boost-type active power factor corrector (PFC), Under light-load condition. the circuit is operated at a Quasi-Resonant (QR) mode or a Boundary Conduction Mode (BCM) to reduce switching losses. Otherwise. the circuit is operated at Continuous Conduction Mode (CCM) under heavy load condition to reduce the device current stresses. Firstly, the operation principles and the zero-voltage switching condition for an ideal power factor correction are analyzed and discussed. Then, two 300W dual-mode boost-type power factor correctors are built and tested to verify the above theoretical analysis, The control circuits of the laboratory prototypes are implemented by using the Texas Instruments chip UC 3854 and external auxiliary circuits, The experimental results are shown to verify the feasibility of the studied schemes. High conversion efficiency can be achieved under light-load conditions and device current stresses can be reduced effectively under heavy-load conditions.
Zai, Zong-ru, and 蔡宗儒. "Design of Robust Dual Boost Converter Power Factor Correction Circuits." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/77714214170830200229.
Повний текст джерела國立中山大學
電機工程學系研究所
99
The traditional AC/DC rectifier usually has the defects of low power factor and serious harmonic distortion and it results in serious pollution to the power system. This thesis proposes active power factor correction technique using a new AC/DC Dual Boost Converter. For power factor correction, inductor current is operated in the continuous conduction mode. First, the converter is analyzed by state space averaging method. Furthermore, we design applicable compensator by frequency analysis to implement a good power factor system. A classical PFC circuit with PI control law has low power factor under light load. In order to overcome problem, the thesis proposes a Dual Boost Converter circuit with robust performance. Comparing with circuits using PFC IC “UC3854”, the proposed system obtains higher power factor under the condition of the same light load.
Zhan, Zi-zeng, and 詹子增. "Study and Implementation of a Dual-Mode Buck Power Factor Corrector." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/55834889185565944492.
Повний текст джерела國立臺灣科技大學
電子工程系
102
This thesis aims to study a dual-mode buck active power factor corrector (PFC). Under light-load condition, the circuit is operated at boundary conduction mode (BCM) to reduce the switching loss. Otherwise, the circuit is operated at continuous conduction mode (CCM) under heavy-load condition. The peak inductor current is reduced and the conduction loss is less. First, the loss distributions of the PFC at various load levels for both BCM and CCM are analyzed. Therefore, a transition point can be found to switch between the two control modes. A 150-W dual-mode buck PFC prototype is built to verify the circuit analysis and design considerations. The control circuits of the laboratory prototype are implemented by using the STMicroelectronics chip L6561 and additional external circuits. Experimental results show that the studied PFC actually operates under BCM from light-load to half-load conditions to reduce the switching loss, and under CCM at heavy loads to reduce the conduction loss.
Lin, Chien-Tu, and 林建宇. "Design Optimization of a Dual-Mode Boost-Type Power Factor Corrector." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/68374408369492547693.
Повний текст джерела國立臺灣科技大學
電子工程系
98
The main purpose of this thesis is to propose a new control method for a boost-type power factor corrector (PFC). The presented PFC is operated under boundary conduction mode (BCM) at lighter loads and continuous conduction mode (CCM) at heavier loads. The MOSFET is turned on with zero current, and thus zero switching loss, when the PFC is operated under BCM. However, the peak inductor current is higher and therefore the conduction loss increases as the load gets heavier. On the other hand, the output diode has reverse recovery phenomenon that results in a higher switching loss when the PFC is operated under CCM. This problem is more obvious as the load decreases. Nevertheless, under CCM, the peak inductor current is smaller and the conduction losses are smaller, too. A novel dual-mode PFC controller is proposed in this thesis, with BCM operations at light loads and CCM operations at heavy loads, to take the advantages and improve the disadvantages of both modes. First the loss distributions of the PFC at various load levels for both BCM and CCM are analyzed. Therefore, a most suitable transition point can be found to switch between the two control modes. A 300-W dual-mode boost-type PFC prototype is built to verify the circuit analysis and design considerations. Experimental results show that the studied PFC actually operates under BCM at light loads to reduce the switching loss, and under CCM at heavy loads to reduce the conduction loss.
Hsieh, Shi-Yuan, and 謝時淵. "A High-Power-Factor AC/DC Converter with Dual Flyback Conversion Circuits." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/73t6qy.
Повний текст джерела義守大學
電機工程學系
104
This thesis proposes a high power-factor AC-DC converter with two flyback conversion circuits. The interleaved flyback converters adopt two power MOSFETs as the active switches. With no need to use any auxiliary components and snubber circuit, both active switches can operate at zero-voltage switching on (ZVS) by freewheeling the inductor current through the body diode of the MOSFET. Operating active switches at ZVS can effectively decrease the switching losses, and hence improve the circuit efficiency. As comparing the proposed interleaved circuit with traditional one, the former is with the advantage of lower current and voltage ripples. It helps to decrease the current and voltage stresses on the circuit components. Besides, the circuit reliability can be improved. The detail circuit operation and analysis are provided. A prototype circuit of a 200-W converter was built and tested. The experimental results show that the switching losses can iii be effectively reduced by operating the active switches at ZVS. The proposed circuit can achieve nearly unity power factor and the measured circuit efficiency is 93.25%.
Yang, Cheng-yan, and 楊政諺. "Study and Implementation of a Dual-Mode Push-Pull Boost Power Factor Corrector." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/2r8t77.
Повний текст джерела國立臺灣科技大學
電子工程系
99
The operations of the proposed dual-mode push-pull boost power factor corrector can be under either quasi-resonant (QR) mode or discontinuous conduction mode (DCM). For QR mode operation, the valley-switching on the switch and zero-current-switching (ZCS) of the output diode can reduce the switching losses and improve the conversion efficiency. On the other hand, the DCM operation features fixed switching frequency, ZCS of the output diode, natural PFC function, simplified control methodology and EMI filter design. Circuit principles and design procedures are presented and verified by the simulations and experimental results. A prototype is then implemented with universal line voltage, a 380 V output DC voltage 380 V and 300 W power rating. The minimum efficiencies at line voltages of 100Vac and 220Vac are 94.4% and 96.7%, respectively.
Kauer, Michaela. "Identification as Determining Factor of Technology Acceptance for Hedonic and Dual Use Products." Phd thesis, 2012. https://tuprints.ulb.tu-darmstadt.de/3107/1/DissertationMichaelaKauer.pdf.
Повний текст джерелаWU, JIA-JHOU, and 吳家州. "The role of customer participation in IT services relationship maintenance – a dual-factor perspective." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/qr62me.
Повний текст джерела國立臺灣科技大學
企業管理系
105
The study investigates the influences of customer participation on relationship maintenance by adopting the two-factor model, and identifies potential antecedents of customer participation. Empirical data was collected from 126 firms which receive information technology (IT) services in Taiwan. The results of this study showed that customer participation positively influences customer loyalty through the following mechanisms: 1) service quality and satisfaction, and 2) switching costs. Additionally, IT capabilities, organizational compatibility, and role clarity are positively related to customer participation. The findings can serve as a guideline for IT service firms to promote customer participation and for general enterprises to select IT service firms.
Excell, Peter S., and Z. M. Hejazi. "Compact Superconducting Dual-Log Spiral Resonator with High Q-Factor and Low Power Dependence." 2002. http://hdl.handle.net/10454/3260.
Повний текст джерелаA new dual-log spiral geometry is proposed for microstrip resonators, offering substantial advantages in performance and size reduction at subgigahertz frequencies when realized in superconducting materials. The spiral is logarithmic in line spacing and width such that the width of the spiral line increases smoothly with the increase of the current density, reaching its maximum where the current density is maximum (in its center for ¿/2 resonators). Preliminary results of such a logarithmic ten-turn (2 × 5 turns) spiral, realized with double-sided YBCO thin film, showed a Q.-factor seven times higher than that of a single ten-turn uniform spiral made of YBCO thin film and 64 times higher than a copper counterpart. The insertion loss of the YBCO dual log-spiral has a high degree of independence of the input power in comparison with a uniform Archimedian spiral, increasing by only 2.5% for a 30-dBm increase of the input power, compared with nearly 31% for the uniform spiral. A simple approximate method, developed for prediction of the resonant frequency of the new resonators, shows a good agreement with the test results.
Huang, Shr-Hau, and 黃世豪. "The design and implementation of a 250W dual-switch forward converter with power-factor-correction." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/81182492745866693463.
Повний текст джерелаCHEN, GUANG-JUNE, and 陳廣駿. "A High-Power-Factor Lithium Battery Charger with Dual Bridgeless Single-Stage Resonant Conversion Circuits." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/bp44xx.
Повний текст джерела國立虎尾科技大學
電機工程系碩士班
106
This thesis proposes a high-efficiency and high-power factor lithium battery charger which integrates a bridgeless boost-type power-factor-correction converter and a full bridge LLC resonant circuit to comprise a single-stage topology. The proposed lithium battery charger will be featured with high-efficiency, high power-factor and reduced current and voltage stresses on components by introducing a pair of converters using series-input and parallel-output mechanism. By merging the bridgeless power-factor-correction technique and the full bridge LLC resonant circuit into a single-stage structure, the proposed battery charger achieves the advantages of: (1) bridgeless structure reducing circuit losses;(2) resonant technique usage furnishing power switches with zero-voltage-switching and output stage diodes with zero-current-switching and enhancing the circuit efficiency; (3) constant current and voltage charging power regulation with frequency modulation scheme simplifying the trigger circuit complexity and widening the charging power range; (4) series-input and parallel-output dual converters topology sharing current and voltage stresses and reducing the component rating; (5) paired interleaved power-factor-correction operation sharing current loading and thus increasing charging battery size. Hopefully, this project aims at accomplishing a high power lithium battery charger with high power-factor, high-efficiency, low component rating, electric isolation, zero-voltage-switching and wide charging power range.