Dissertations / Theses on the topic 'Causal fields'
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Johnston, Steven Paul. "Quantum fields on causal sets." Thesis, Imperial College London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526363.
Full textSprickerhof, Jakob. "Causal structures in quantum field theory." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/10658/.
Full textTlas, Tamer. "A causal Spinfoam and new Group Field Theories." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612457.
Full textDang, Nguyen Viet. "Renormalization of quantum field theory on curved space-times, a causal approach." Paris 7, 2013. http://www.theses.fr/2013PA077188.
Full textThe subject of the thesis is the construction of a perturbative quantum theory of interacting fields on a curved space-time, following a point of view pioneered by Stueckelberg and Bogoliubov and developed by Epstein-Glaser on the flat Minkowski space-time. In 2000 a breakthrough was done by Brunetti and Fredenhagen who were able to extend the Epstein-Glaser theory by exploiting the point of view developed by Radzikowski to define quantum states on a curved space-time in terms of wave-front sets. These results were further extended by Fredenhagen, Brunetti, Hollands, Wald, Rejzner, etc. To Yang-Mills fields and the gravitation. However, even for theories without gauge invariance, many mathematical details were left unexplored and unquestioned. The task of Viet was precisely to derive fully rigorously this theory in the case there is no gauge invariance. In my work, I propose a complete review of the result, solving numerous questions, adding many new results around this program and, eventually, giving more precise details on the counterterms and ambiguities in the renormalization process, and a deeper understanding of the geometry of the wave front set of the n-point functions. All this thesis uses various mathematical techniques: differential and pseudo Riemannian geometry, microlocal analysis and the symplectic geometry of wavefront sets, functional analysis, fine results from the theory of distributions, Hopf algebras, etc
Djapic, Lilijana. "Determination of residual stress fields caused by shot peening." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338587.
Full textIbnouhsein, Mohamed Issam. "Quantum correlations and causal structures." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112426/document.
Full textRecent works in foundations of quantum (field) theory and relativistic quantum information try to better grasp the interplay between the structure of quantum correlations and the constraints imposed by causality on physical operations. Chapter 1 is dedicated to the study of the conceptual implications of quantum nonlocality, a concept that subsumes that of entanglement in a certain way. We detail the recent information-theoretic approaches to understanding the structure of nonlocal correlations, and the issues the latter raise concerning the ability of local observers to isolate a system from its environment. Chapter 2 reviews in what sense imposing Poincaré invariance affects entanglement detection and quantification procedures. This invariance ultimately forces a description of all quantum systems within the framework of quantum field theory, which leads to the impossibility of localized finite-energy states and to the divergence of all entanglement measures for local observers. We provide a solution to these two problems by showing that there exists a generic equivalence between a finite spatial resolution of the measurement apparatus and the exclusion of high-energy degrees of freedom from the definition of the observed system. This equivalence allows for an epistemic interpretation of the standard quantum formalism describing nonrelativistic localized systems and their correlations, hence a clarification of the origin of the finite measures of entanglement between such systems. Chapter 3 presents a recent theoretical framework that predicts the existence of correlations with indefinite causal order. In analogy to the information-theoretic approaches to nonlocal correlations, we introduce some principles that constrain the structure of such correlations, which is a first step toward a clear understanding of their physical origin
OLIVERO, CARLOTTA. "Defining the causal association between human beta papillomavirus infection, keratinocyte stem cells expansion and skin cancer development." Doctoral thesis, Università del Piemonte Orientale, 2017. http://hdl.handle.net/11579/87003.
Full textYoboue, Tchindji Houphouët Félix. "Le viol comme arme de guerre en Côte d'Ivoire (1999-2010) : champs de causalité entre brisures, savoirs contaminés et vérités en ruines. Le plain-chant des narrations ethnophotographiques et du hors texte de 13 survivantes du peuple guéré à DUEKOUÉ en contre-configuration." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0276.
Full textThe accounts of thirteen survivors of rapes suffered in Duékoué, a crossroads city located in the west of Côte d'Ivoire, during the failed coup d'état of September 19, 2002 until the postelectoral crisis of 2010, constitute the narrative matrix of this thesis. These 13 women are survivors, with the astonishment, the anguish, the despair of the survivors. Where can we still find meaning when we have lived what they have lived and are still living ten years later? Indeed, the survivors continue to live in a permanent hell, victims of slow forms of invisible violence, a subtle form of social assassination through the brutal exclusion from family and community, through the predominantly patriarchal and of a disrespectful reparation; collateral consequences little or not documented or even denied. This thesis tries to propose answers to three essential questions. How to advance a research that is formally more complex than others, with a reflection on the tensions of Ivorian history, the stories of the survivors, the story of the researcher-baoulé-survivor and aesthetic proposals for writing it? How to write scientifically about vulnerability, distress and suffering and stay at a distance? How to restore the song of the actor-witnesses in the original expression, of these "tiny lives", with the choppy, stammering speech, and make it dialogue with the vigorous and assertive speech of a researcher who actually discovers during a particular day that he is in search of his own word, that of a survivor, buried in a padlocked gangue. It was necessary to be able to render the adhesion of the baoulé researcher to his own word and in his faith in the capacities of language to reach the untouchable and the invisible, a lost world, the past itself. It was necessary to try to multiply the narrative detours and the formal tracks, and to take the risk of rejecting certain narrative university codes in order to make palpable, by transforming a material that is difficult to handle and highly flammable, this violence experienced by the survivors of whom Michel Foucault says: "that what is most dangerous in violence is its rationality”. It is also for this reason, to make the distant waves of this suffering expressed more particularly felt and the certainty that we often overlook, that the choice of photoethnographic narrations was imposed. To confront each of the readers with their own relationship to the image and, in a more subtle way, to the stories of the survivors. Which then leads us to reflect on the enigma of appearances. “Read what has never been written”. To see violence in its truth, only an anthropology of attention that would resonate with what Edouard Glissant calls "the deep", thus designating "what there is really, concretely, below the appearance », making it possible to resuscitate the dignity of life of the survivors and to legitimize the writing of a committed researcher
Siegel, Thomas A. "Magnetic fields of an underground coaxial cable caused by return currents in the earth." Ohio : Ohio University, 1989. http://www.ohiolink.edu/etd/view.cgi?ohiou1182517321.
Full textWatkins, Gavin Hughes. "Field and experimental investigations of ovine mastitis caused by Pasteurella Haemolytica." Thesis, Royal Veterinary College (University of London), 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.522804.
Full textBaloyi, Mafemani Phanuel. "Perceptions on the causes of poverty : field study at Mavambe Village." Thesis, University of Limpopo, Turfloop Campus, 2013. http://hdl.handle.net/10386/1101.
Full textThe purpose of this study was to understand the perceptions on the causes of poverty amongst the people at Mavambe village. The need for this study was relevant and necessary because most studies conducted on poverty were done on a general scale without taking into account the views of the rural people, such as traditional, community leaders and also local women. Consideration towards the rural areas is very minimal when it comes to fighting poverty. According to the Constitution of the Republic of South Africa, (1996), everyone has the right to have access to adequate housing, and the right to access health care services, including productive health care, sufficient food and water, social security. South Africa has had almost eighteen years of democracy; however most of those constitutional rights have not been adequately attained. Yet the Constitution suggests that those rights are guaranteed and that the state must take reasonable steps, to achieve the progressive realization of those rights. The study was qualitative in design. Purposive sampling was used to select the respondents in line with qualitative studies. In-depth interviews and focus group discussions were conducted with respondents The lack of houses, clean drinking water, adequate sanitation, and poor roads, in rural areas are major signs of poverty in rural areas. Because of lack of jobs and resources, majority people are in abject poverty. The study evaluated the scope and extent of poverty in the Mavambe village. The study further evaluated the perceptions of local, traditional and community leaders with regard to causes of poverty in the area. The study also solicited local people‟s perceptions and descriptions of poverty. The study highlights the multidimensionality of poverty. The study made the following key findings, there is lack of agricultural land and capital, the study recommends that every household should have little piece of land to grow crops and other productive uses and that those who want to do commercial farming should be assisted with capital. Another key finding is on income and social grant, the study recommends that the elderly and mothers who are not of school going age should be given social grant not school kids. The study also revealed that poor education system is a major cause of poverty and recommends that government must provide quality education, health, housing and sanitation. The study also revealed that there is lack of entrepreneurial development and thus recommends that entrepreneurial culture be natured as a viable option to deal with 6 issues of unemployment. The study also revealed that there is no infrastructure development in the rural areas and recommends that this should be given priority to change the economic set up of these areas. The study revealed that there is lack of values, respect and moral decay and recommends that families should cultivate and teach values to their children. The study concluded by providing recommendations on how poverty could be solved. These recommendations could also be of assistance for future policy development with regard to combating poverty.
Vogelsang, Timo [Verfasser], Dirk [Gutachter] Sliwka, and Matthias [Gutachter] Heinz. "Management Practices and Employee Performance - Causal Evidence from Field- and Laboratory Experiments / Timo Vogelsang ; Gutachter: Dirk Sliwka, Matthias Heinz." Köln : Universitäts- und Stadtbibliothek Köln, 2020. http://d-nb.info/1213446139/34.
Full textNishizawa, Shinichiro. "Induced current density in human body models caused by inhomogeneous magnetic fields of electrical appliances." Berlin Logos-Verl, 2005. http://deposit.ddb.de/cgi-bin/dokserv?id=2672479&prov=M&dok_var=1&dok_ext=htm.
Full textKlangboonrong, Yiarayong. "Modes of knowledge production : articulating coexistence in UK academic science." Thesis, Cranfield University, 2015. http://dspace.lib.cranfield.ac.uk/handle/1826/9618.
Full textMavaleix-Marchessoux, Damien. "Modelling the fluid-structure coupling caused by a far-field underwater explosion." Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAE012.
Full textSubmarines must withstand the effects of rapid dynamic loads induced by underwater explosions. Due to the very high cost of experimental campaigns, numerical simulations are very important. A remote underwater explosion is a complex event that has two distinct effects: it sends a shock wave, then creates an oscillating gas bubble that sets water in slower motion. The two phenomena have quite different characteristics and time scales. In this work, we consider remote enough underwater explosions so that (i) the presence of the submarine only marginally affects the explosion, and (ii) there is a temporal separation of the two phenomena, as experienced by the ship. Under these conditions, our overall goal is to design, implement (in the context of high performance computing) then validate a computational methodology for the fluid-structure interaction problem, taking into account both phenomena. With this aim, we first study the two perturbations without considering the submarine, to propose appropriate modelling and numerical methods. Then, we design a fast boundary element (BEM) procedure, based on the combination of the convolution quadrature method and an original empirical high frequency approximation. The procedure allows to efficiently simulate 3D rapid transient wave propagation problems set in an unbounded domain, and shows advantageous complexity: O(1) in regards to the time discretisation and O(N log N) for the spatial discretisation. Finally, we implement adequate finite element/boundary element (FEM/BEM) coupling strategies for the shock wave fluid-structure interaction phase (linear acoustics) and that of the gas bubble (incompressible flow). The overall procedure, validated on academic problems, provides very promising results when applied on realistic industrial cases
Kleiner, Johannes Verfasser], and Felix [Akademischer Betreuer] [Finster. "Dynamics of Causal Fermion Systems - Field Equations and Correction Terms for a New Unified Physical Theory / Johannes Kleiner ; Betreuer: Felix Finster." Regensburg : Universitätsbibliothek Regensburg, 2017. http://d-nb.info/1143948955/34.
Full textOliver, Charlotte. "Phylogeny, histological observation, and in vitro fungicide screening and field trials of multiple Colletotrichum species, the causal agents of grape ripe rot." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/99418.
Full textPHD
Baris, A. N. Dalsu. "Suicide and other causes of death in electrical utility workers : their association with exposure to electric and magnetic fields." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28672.
Full textThe first paper reports a historical cohort mortality study which was carried out among 21,744 electrical utility workers in the province of Quebec. A total of 1582 deaths were observed at the end of follow-up (1970-1988). A job exposure matrix (JEM) was used to estimate the exposure to 60 Hz electric, magnetic, and pulsed electromagnetic fields (PEMF) from the code of the last job held by each worker. The results showed no evidence of excess of cause specific or general mortality relative to provincial death rates in the cohort overall. The ratios of Standardized Mortality Ratios (SMRs) as estimates of rate ratio (RR) in the exposed relative to the background group were also calculated. Statistically significant RRs were found for pancreatic cancer for electric fields (RR = 2.8, 95% Confidence intervals (CI) 1.13-7.01) and for lung cancer for PEMF (RR = 1.56, 95% CI 1.05-2.25). Deaths caused by accidents and violence showed significant RRs for electric fields (RR = 2.16, 95% CI 1.59-2.92), magnetic fields (RR = 1.76, 95% 1.29-2.39) and for PEMF (RR = 1.96, 95% CI, 1.40-2.71). Occupational accidents related to power lines explain for some of the excess of deaths from accidents and violence. There was a small non-significant association with magnetic fields for leukaemia (RR = 1.52, 95% CI 0.45-4.47) and brain cancer (RR = 1.59, 95% CI 0.57-4.31), but the results for these two sites were based on small numbers.
The second paper reports a case-cohort study to investigate a previously suggested association between exposure to electric and magnetic fields and suicide. Forty-nine deaths from suicide between 1970 and 1988 were identified in the above-mentioned cohort and a sub-cohort comprising a one percent random sample was selected from it. Cumulative and current exposures to electric fields, magnetic fields and PEMF were estimated for the sub-cohort and cases through the JEM. For cumulative exposure, rate ratios (RR) for all three fields showed mostly small non-significant increases in the medium and high exposure groups. The most elevated risk was found in the medium exposure group for electric field-geometric mean (RR = 2.76, 95% CI 1.15-6.62). The results did not differ after adjusting for socioeconomic status (SES), alcohol use, marital status and mental disorders. There was little evidence for an association of risk with exposure immediately prior to the suicide. Small sample size (deaths from suicide) and inability to control for all potential confounding factors were the main limitations of this study.
The third paper reports a study of validity attributing magnetic field exposure by using a worker's last job. This was done by comparing, in a sample of the cohort, estimates obtained using last job with those obtained using full work histories. The correlation between indices based on last job and those based on all jobs varied between 0.75 and 0.78. The study showed that the last job was particularly good in identifying the highest exposed individual. The results are most likely to be generalizable to other industries in which highest exposed jobs are also skilled jobs.
Gauthier, Robert P. (Robert Paul) 1965. "An investigation of flow field perturbation caused by constant blade tip clearance in a turbine." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/14150.
Full textMatta, Corrado. "A Field of Veiled Continuities : Studies in the Methodology and Theory of Educational Research." Doctoral thesis, Stockholms universitet, Institutionen för pedagogik och didaktik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-140475.
Full textAt the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.
Sassen, Douglas Spencer. "Pseudokarst topography in a humid environment caused by contaminant-induced colloidal dispersion." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/455.
Full textTröger, Sven, and Matthias Kröger. "Damage of bearings caused by electrical discharge currents at large drives derived from latest field research results." TU Bergakademie Freiberg, 2019. https://tubaf.qucosa.de/id/qucosa%3A38455.
Full textTheint, Ei P. "Empirical Analysis of Causes of Income Inequality: A Level Playing Field for Children at the Start of School Career." Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/scripps_theses/416.
Full textPuig, Garcia Mireia. "Synthetic antifungal peptides for controlling brown spot of pear caused by Stemphylium vesicarium. Activity, mode of action and field evaluation." Doctoral thesis, Universitat de Girona, 2015. http://hdl.handle.net/10803/387564.
Full textL’estemfiliosi de la perera és una malaltia causada pel fong Stemphylium vesciarium. Actualment, els mètodes de control presenten una eficàcia limitada. Aquesta tesi es centra en millorar-ne el control mitjançant pèptids antimicrobians com a alternativa o suport als fungicides actuals. Dotze pèptids antimicrobians de la llibreria CECMEL11 van ser avaluats in vitro enfront el fong. El més eficaç va ser el péptid BP15 amb una concentració mínima inhibitòria (CMI) de 10 µM. Aquest pèptid es va mostrar eficaç en el control de la malaltia en assajos ex vivo i aplicat a camp, seguint el model de predicció BSPcast. En l’estudi dels mecanismes d’acció del BP15 es va determinar que el pèptid permeabilitza la membrana cel•lular del fong i que és internalitzat per les cèl•lules dels tubs germinatius i de les hifes de S. vesicarium.
MASSA, LAURA. "Profili evolutivi del diritto degli appalti. Il paradigma delle cause di esclusione." Doctoral thesis, Università degli Studi di Cagliari, 2015. http://hdl.handle.net/11584/266834.
Full textTvedt, Chryseis Theresa. "Efficacy of Seed Treatments and In-Furrow Fungicides for Management of Dry Bean Root Rot Caused by Rhizoctonia Solani and Fusarium Solani, and Field Pea Root Rot Caused by Fusarium Avenaceum and Fusarium Solani." Thesis, North Dakota State University, 2017. https://hdl.handle.net/10365/28366.
Full textMeloling, John H. "A caustic corrected uniform geometrical theory of diffraction for evaluating high-frequency electromagnetic fields near the cusp of the caustic caused by the curvature of an edge /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487853913101801.
Full textMuhdi, Rani. "Re-Engineering the Operational System to Enhance the Customer Orientation of a Mid-Size Firm: A Field Study." [Johnson City, Tenn. : East Tennessee State University], 2002. http://etd-submit.etsu.edu/etd/theses/available/etd-0319102-195053/restricted/Muhdir041002a.PDF.
Full textUrs, Radu Dragos. "Non-parametric synthesis of volumetric textures from a 2D sample." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00821886.
Full textSaha, Shrabani. "Causes of corruption : an empirical investigation in a cross-country framework : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosphy in Economics, Massey University, Turitea campus, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1327.
Full textKhan, Khalid. "The violation of psychological contract : possible causes for the failure of organizational incentive systems to motivate knowledge sharing : a thesis presented in partial fulfilment of the requirements for the degree of Master of Management in Human Resource Management, Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1223.
Full textCARDOSO, Alessandra Marques. "Surto de infecção após videoscopias causado por Mycobacterium massiliense em Goiânia-GO : análise molecular e determinação da suscetibilidade aos antimicrobianos." Universidade Federal de Goiás, 2009. http://repositorio.bc.ufg.br/tede/handle/tde/1590.
Full textIn recent years the number of infections caused by microbacteria non-tuberculous mycobacteria (NTM) has increased mainly due to opportunistic infections in individuals imunocompormetidos and improvement of farming techniques and identification of MTN. Mycobacterium massilienese is an emerging body associated with wound infections, abscesses and pneumonia. An outbreak of infection after videoscopy occurred between 2005 and 2007 in seven hospitals in Goiânia-GO, in central Brazil. The objective of this study was to identify NTM isolated from patients with infection after arthroscopy and lararoscopia by PCR followed by analysis of fragment length polymorphism restrção (PRA-hsp65), compared by gel electrophoresis pulsed-field gel (PFGE), sequencing of the partial rpoB gene and determination of antimicrobial susceptibility in vitro. NTM were recovered from samples (exudate abscess subcutâneio) of 18 patients involved in the outbreak. In the period leading up to this study there was no reported case of infection after videoscopy caused by MTN in Goiania. The 18 isolates were identified as M, massiliene and genotyped as a single clone, indicating that they had a common origin, suggesting a common source of infection for the patients involved in the outbreak. The epidemic isolates were susceptible to amikacin (MIC90 4 micrograms / ml) and clarithromycin (MIC90 <1 ug / ml), but resistance to ciprofloxacin (MIC90 <128g/ml), tobramycin (MIC90 32 micrograms / ml) and intermediate susceptibility to cefoxitin (MIC90 64 ug / ml). In conclusion this study demonstrated the clonality of strains of M. massiliense involved in infections after procedures videoscopes and that they are susceptible to drugs indicated for the treatment
Durante os últimosd anos o número de infecções causadas por microbactérias não-tuberculosas (MNT) tem aumentado principalmente devido às infecções oportunistas em indivíduos imunocompormetidos e ao aprimoramento das técnicas de cultura e identificação das MTN. Mycobacterium massilienese é um organismo emergente, associado a infecções de feridas, formação de abscessos e pneumonias. Um surto de infecção após videoscopias ocorreu entre 2005 e 2007 em sete hospitais privados de Goiânia-GO, na região central do Brasil. O objetivo deste estudo foi identificar MNT isoladas de amostras de pacientes com infecção após artroscopia e lararoscopia por PCR seguida de análise de polimorfismo de fragmentos de restrção (PRA-hsp65), comparação por eletroforese em gel em campo pulsado (PFGE), sequenciamento parcial do gene rpoB e determinação da suscetibilidade antimicrobiana in vitro. MNT foram recuperadas das amostras (exsudato de abscesso subcutâneio) de 18 pacientes envolvidos no surto. No período antecedente a esse estudo não houve nenhum relato de caso de infecção após videoscopias causada por MTN em Goiânia. Os 18 isolados foram identificados como M, massiliene e genotipados como um único clone, indicando que tiveram uma origem em comum, o que sugere uma fonte comum de infecção para os pacientes envolvidos no surto. Os isolados epidêmicos apresentaram sensibilidade a amicacina (CIM90 4 ug/ml) e claritromicina (CIM90 < 1 ug/ml), porém resistência a ciprofloxacina (CIM90 < 128g/ml), tobramicina (CIM90 32 ug/ml), e sensibilidade intermediária a cefoxitina (CIM90 64 ug/ml). Em conclusão este estudo evidenciou a clonalidade de cepas de M. massiliense envolvidas em infecções após procedimentos de videoscopia e que as mesmas são suscetíveis às drogas indicadas para o tratamento
Zhang, Mei. "Diagnostic de panne et analyse des causes profondes du système dynamique inversible." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30260/document.
Full textMany of the vital services of everyday life depend on highly complex and interconnected engineering systems; these systems consist of large number of interconnected sensors, actuators and system components. The study of interconnected systems plays a significant role in the study of reliability theory of dynamic systems, as it allows one to investigate the properties of an interconnected system by analyzing its less complicated subcomponents. Fault diagnosis is crucial in achieving safe and reliable operations of interconnected control systems. In all situations, the global system and/or each subsystem can be analyzed at different levels in investigating the reliability of the overall system; where different levels mean from system level down to the subcomponent level. In some cases, it is important to determine the abnormal information of the internal variables of local subsystem, in order to isolate the causes that contribute to the anomalous operation of the overall process. For example, if a certain fault appears in an actuator, the origin of that malfunction can have different causes: zero deviation, leakage, clogging etc. These origins can be represented as root cause of an actuator fault. This thesis concerns with the challenges of applying system inverse theory and model based FDD techniques to handle the joint problem of fault diagnosis & root cause analysis (FD & RCA) locally and performance monitoring globally. By considering actuator as individual dynamic subsystem connected with process dynamic subsystem in cascade, we propose an interconnected nonlinear system structure. We then investigate the problem of left invertibility, fault observability and fault diagnosability of the interconnected system, forming a novel model based multilevel FD & RCA algorithm. This diagnostic algorithm enables individual component to monitor internal dynamics locally to improve plant efficiency and diagnose potential fault resources to locate malfunction when operation performance of global system degrades. Hence, a means of acombination of local intelligence with a more advanceddiagnostic capability (combining fault monitoring anddiagnosis at both local and global levels) to performFDDfunctions on different levels of the plantis provided. As a result, improved fault localization and better predictive maintenance aids can be expected. The new system structure, together with the fault diagnosis algorithm, is the first to emphasize the importance of fault RCA of field devices, as well as the influences of local internal dynamics on the global dynamics. The developed model based multi-level FD & RCA algorithm is then a first effort to combine the strength of the system level model based fault diagnosis with the component level model based fault diagnosis. The contributions of this thesis include the following: Firstly, we propose a left invertible interconnected nonlinear system structure which guarantees that fault occurred in field device subsystem will affect the measured output of the global system uniquely and distinguishably. A necessary and sufficient condition is developed to ensure invertibility of the interconnected system which requires invertibility of individual subsystems. Second, a two level interconnected observer is developed which consists of two state estimators, aims at providing accurately estimates of states of each subsystem, as well as the unknown interconnection. In addition, it will also provide initial condition for the input reconstructor and local fault filter once FD & RCA procedure is triggered by any fault. Two underlyingissues are worth to be highlighted: for one hand, the measurement used in the estimator of the former subsystem is assumed not accessible; the solution is to replace it by the estimate provided by the estimator of the latter subsystem. In fact, this unknown output is the unknown interconnection of the interconnected system, and also the input of the latter subsystem
Lane, Karl. "The feasibility of using remote sensing and field-based checks to monitor the impact caused by collection of wood in the Eastern Cape/Ciskei forest and thicket formations." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/21929.
Full textA variety of studies have shown the problems of energy supply faced by low-income communities in southern Africa. Most of these communities are dependent upon indigenous fuelwood supplies. In addition, many of these communities use indigenous wood for construction. This largely uncontrolled utilisation imposes severe threats on woody vegetation communities. The Eastern Cape/Ciskei region is an area where energy supply problems are particularly severe and impacts on woody vegetation correspondingly severe. This study aimed to investigate the feasibility of using remote sensing techniques to monitor the the impact caused by collection of wood in the Eastern Cape/Ciskei forest and thicket communities. A variety of remote sensing techniques for landcover analysis were investigated. In all cases, visual interpretation was used because it is considerably cheaper and demands less technical expertise than would computer processing. In addition, many studies have shown visual interpretation to be superior. Maps were drawn from multitemporal aerial photograph sequences and from Landsat and SPOT satellite images. These maps showed that there has been relatively little change in area of woody vegetation in the study area since 1956. However, field studies showed that vegetation community structure had been degraded as a result of intense and sustained human impact. This qualitative decline also reflected a decline in usefulness of the woody vegetation of the area to local communities. This substantial degradation was not visible on any of the remote sensing imageries. This emphasises that field-based checks to monitor human impacts on forest and thicket formations are essential. Strategies for reducing the dependence of low-income communities on indigenous vegetation for energy supplies and constructional timber have been reviewed from the literature and these are descibed in Appendix 1. Most successful strategies in other parts of the world have been the result of a national commitment to tree planting, recognition of a multiplicity of constraints and the voluntary involvement of the communities the strategies are intended to assist.
Mateus, Forero Andrea D. "DESIGN IN ADAPTATION TO DROUGHTS AND HEAT WAVES CAUSED BY CLIMATECHANGE IN RICE FARMS IN LERIDA, TOLIMA, COLOMBIA." Miami University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=miami151213167340772.
Full textLandwehrlen, Thomas. "Le déclin du Bayernpartei et ses déterminants causaux (1949-1969) : plaidoyer pour une analyse plurifactorielle et anti-retrospectiviste." Thesis, Lyon 2, 2011. http://www.theses.fr/2011LYO20114.
Full textFounded in Munich in October 1946 after the reorganisation of a proto-party combining rejection of authoritarian unitarism and anti-Prussian provincialism, the Bavaria Party (Bayernpartei) appeared after the Second World War as the spreader of the Bavarian claims for autonomy, and as the echo box of popular hostility against German refugees from Central and Eastern Europe. After having been crowned with success at the German federal election of 1949 – on which it collected 20,9% of the votes in Bavaria –, he was affected during two decades by a steady electoral decline, so much so that it completely ceased to be “relevant” in the sense of Sartori at the very time when political scientists were witnessing at European (and even Western) level a new upsurge of regionalist parties and organisations.What are the causal determinants of the progressive decline of the Bavaria Party? What explanatory factors can be advanced to account for its gradual transformation into what Manfred Rowold considers to be a simple and irrelevant folk association? This is the question underlying the present work and to which the author proposes to respond by working on the assumption that it is necessary to break with the monocausal, linearist and exogenousing retrospectivism characterizing the analyses of the (rare) political scientists who have already attempted to explain the withering away of the Bavarian regionalist party
Trucíos, Caciano Ramón [Verfasser], Christoph [Akademischer Betreuer] Kleinn, Christoph [Gutachter] Kleinn, and Rivas José Javier [Gutachter] Corral. "Quantifying the uncertainty caused by sampling, modeling, and field measurements in the estimation of AGB with information of the national forest inventory in Durango, Mexico / Ramón Trucíos Caciano ; Gutachter: Christoph Kleinn, José Javier Corral Rivas ; Betreuer: Christoph Kleinn." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/121070272X/34.
Full textErbas, Cihan. "Validation of remotely-sensed soil moisture observations for bare soil at 1.4 GHz a quantitative approach through radiative transfer models to characterize abrupt transitions caused by a ponding event in an agricultural field, modifications to the radiative transfer models, and a mobile ground-based system /." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3371777.
Full textGeorge, Aaron Geoffrey Lewis. "When Cowboys Come Home: Re-Imagining Manhood in Post-World War II America." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1491953123424439.
Full textAraneda, Bernardo Gabriel. "Simetrías ocultas, twistors, y estabilidad de campos lineales en agujeros negros." Doctoral thesis, 2018. http://hdl.handle.net/11086/6424.
Full textEn el marco del problema de estabilidad de agujeros negros, esta tesis trata diversos aspectos de las ecuaciones de campos libres sin masa sobre espacio-tiempos curvos, con énfasis en espacios algebraicamente especiales que contienen agujeros negros como soluciones particulares. El enfoque central es el estudio de la posible correspondencia entre campos escalares y campos de spin superior, y de la existencia y origen de simetrías ocultas y ciertos mecanismos asociados a la teoría de twistors. Encontramos fórmulas explícitas de esta correspondencia, y mostramos que el patrón de simetrías subyacente se entiende desde el punto de vista de la covariancia conforme y la existencia de estructuras complejas en el espacio-tiempo. Analizamos también aspectos de estabilidad de los campos en el caso de agujeros negros estáticos asintóticamente anti-de Sitter. Estudiamos espacio-tiempos tanto de cuatro como de altas dimensiones.
In the context of the black hole stability problem, this thesis deals with several aspects of the massless free field equations on curved spacetimes, with emphasis on algebraically special spaces that contain black hole solutions as particular cases. The main approach is the study of the possible correspondence between scalar fields and higher spin fields, and of the existence and origin of hidden symmetries and certain mechanisms associated to twistor theory. We find explicit formulas for this correspondence, and we show that the underlying symmetry pattern is understood from the point of view of conformal covariance and the existence of complex structures on the spacetime. We also analyze aspects of the stability of the fields in the case of asymptotically anti-de Sitter static black holes. We study spacetimes of both four and higher dimensions.
Banerjee, Shrabastee. "Empirical stadies of online markets: the impact of product page cues on consumer decisions." Thesis, 2021. https://hdl.handle.net/2144/42547.
Full textGörlich, Andrzej. "Causal dynamical triangulations in four dimensions." Praca doktorska, 2010. http://ruj.uj.edu.pl/xmlui/handle/item/38405.
Full textDʹyachkov, Mikhail. "Longitudinal instabilities of bunched beams caused by short-range wake fields." Thesis, 1995. http://hdl.handle.net/2429/7226.
Full textSantos, João Pereira dos. "Measuring causal impacts with natural and field experiments: evidence for firms, workers, consumers, and voters." Doctoral thesis, 2021. http://hdl.handle.net/10362/118704.
Full text"Fully nonparametric efficient estimation for some causal inference problems and well-posedness on mean field theory." 2015. http://repository.lib.cuhk.edu.hk/en/item/cuhk-1291689.
Full textThesis Ph.D. Chinese University of Hong Kong 2015.
Includes bibliographical references (leaves 207-217).
Abstracts also in Chinese.
Title from PDF title page (viewed on 04, November, 2016).
Chang, Che-Wei, and 張哲瑋. "A Flow Field Experimental Study on BCF Swimming of Bionic-Flexible Caudal Fin." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/99931972791476518912.
Full text國立臺灣大學
應用力學研究所
102
Abstract In this study, we investigate three-dimensional thrust mechanisms of finite rigid and deformable flapping plates experiment as a caudal fin of the BCF (body and/or caudal fin) swimming fish at low Reynold numbers , water propeller vehicles in recent years, many scientist involved in research, and biomimetic water propeller vehicle is popular, with a high from its water propulsion mechanism, both environmental protection, green energy, privacy and so on. The experimental study of the fish BCF swimming field observation, which is characterized by the use of the vortex structure behind it generated vortex propulsion increases with high mobility and operability. Bionic flexible caudal fin is mainly carried out at low Reynolds number, in this case there will be many complex phenomena, such as: reversed-Karman vortex. To simplify the problem, this experiment aspect ratio 1 flapping, using particle imaging, and with the lift and drag measurements. Discuss the development of flexible fin behind and vortex structures. The working fluid is a mixture of experimental glycerol and water, with Reynolds number 500, the number (St=0.2,0.4 and 0.6), and two-way movement. Using the six-axis force compliance record up resistance over time and observe up under a different number St resistance changes with ansys simulation comparison of its results. Flow field observations, with the release of the developer particles to calculate the flow field vorticity with PIV method.
Jhong, Yi-Lun, and 鍾依倫. "The Changes of Paddy Fields in Yuanli Township,Miaoli County and Their Causes." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/49519438108206258869.
Full text中國文化大學
地學研究所地理組碩士班
101
Rice is one of the world's major food crops, and has come through thousands years of evolution in cultivation, diffusion and evolution. The natural conditions in Taiwan are suitable for rice planting, and therefore sustain the crop on the island from coastal plains to the hills. From 1961 to 2010, however, Taiwan rice planting area down to remaining 31%; production was reduced to 58% of the original production. This trend indicates that Taiwan's the rice area and production are declining rapidly, but the decline rate is not equal, this phenomenon is caused by the motivation of this study to explore issues related to the rice space changes and influencing factors. This study takes research plots in Yuanli Township of Miaoli County. Yuanli is regarded as the " barn of Miaoli ". The paddy fields spans from the coast plains to the terrace terrain on the hills in Yuanli. Therefore, to study fluctuation factors of the different terrain area the rice area in the past 50 years, studies have shown to reduce the rice area is the transportation construction in the 1980s to impose agricultural land, change of agricultural land for other types of land use and urban planning, sub-to factor is the impact of agricultural policies ; unit increase in production, the benefit of improved the rice varieties and cultivation techniques; pressing issue at present is engaged in the rice population aging.
LANTOVÁ, Petra. "Causes and consequences of personalities in microtine rodents." Doctoral thesis, 2011. http://www.nusl.cz/ntk/nusl-54437.
Full textMiddleton-Hardie, Catherine. "A mutation in the gene encoding osteoprotegerin causes the severe bone disease Idiopathic Hyperphosphatasia." 2003. http://hdl.handle.net/2292/3173.
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Boev, Ivan Krasimirov. "Radiated Electric and Magnetic Fields Caused by Lightning Return Strokes to the Toronto CN Tower." Thesis, 2010. http://hdl.handle.net/1807/24689.
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