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1

Nielsen, Nikolaj [Verfasser], and Albrecht [Akademischer Betreuer] Schwab. "Function of ion transport proteins in pancreatic stellate cells (PSCs) / Nikolaj Nielsen ; Betreuer: Albrecht Schwab." Münster : Universitäts- und Landesbibliothek Münster, 2015. http://d-nb.info/1138281395/34.

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2

Sampaio, Cristina Cardoso. "Pancreatite alcoólica." Master's thesis, [s.n.], 2014. http://hdl.handle.net/10284/4842.

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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas
A pancreatite alcoólica é uma das principais complicações do consumo excessivo de álcool. O risco de desenvolver a doença aumenta com a ingestão de doses crescentes de álcool, sugerindo que os efeitos tóxicos estão relacionados com a quantidade de álcool ingerida. No entanto, apenas uma minoria dos alcoólicos desenvolve pancreatite, o que indica a necessidade de um fator desencadeador adicional para iniciar a lesão pancreática clinicamente evidente. A pancreatite alcoólica começa como um processo agudo necroinflamatório/ autodigestivo, progredindo com repetidos episódios de necroinflamação. O seu espectro clínico inclui pancreatite aguda (dor abdominal aguda e elevados níveis séricos das enzimas pancreáticas) e pancreatite crónica (dor abdominal, má digestão e diabetes). Têm sido feitos avanços significativos que fornecem uma visão sobre os mecanismos moleculares da lesão pancreática provocada pelo álcool, principalmente no que diz respeito aos seus efeitos tóxicos sobre as células acinares pancreáticas e recentemente, nas células estreladas pancreáticas (PSCs), que desempenham um papel fundamental na fibrose, caraterística da pancreatite crónica alcoólica. Alcoholic pancreatitis is a major complication of alcohol abuse. The risk of developing pancreatitis increases with increasing doses of alcohol, suggesting that alcohol exerts dose-related toxic effects on the pancreas. However, it is also clear that only a minority of alcoholics develop the disease, indicating that an additional trigger may be required to initiate clinically evident pancreatic injury. Alcoholic pancreatitis is thought to begin as an acute necroinflammatory/autodigestive process in a susceptible individual and to progress with repeated episodes. The clinical spectrum of the disease includes acute pancreatitis (acute abdominal pain and raised sérum levels of pancreatic enzymes) and chronic pancreatitis (abdominal pain, maldigestion, diabetes). Significant advances have been made in recent years that provide an insight into the molecular mechanisms of alcohol-related pancreatic injury, particularly with respect to the direct toxic effects of alcohol on pancreatic acinar cells and on the recently characterized PSCs, with may play a key role in the fibrosis of alcoholic chronic pancreatitis.
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3

Alfify, Mohammed. "Impact of IPO on professional soccer clubs." Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCH045.

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Dans les années 1990 et 2000, de nombreux clubs de football professionnel (CFP) ont été inscrits sur les marchés boursiers. Le succès des IPO sur les marchés du football, en particulier dans le domaine des performances sportives et financières, est incertain. Ainsi, nombreux recherches académiques empiriques ont été préconisées pour examiner la performance financière des IPO dans ces clubs. De telles recherches ont révélé que la performance financière des clubs cotés a diminuée. La plupart de ces recherches indiquent qu'il existe une relation entre la performance sportive et la performance financière dans ces clubs. Cependant, les chercheurs n'ont pas déterminé les facteurs de ce phénomène. Pour combler cette lacune dans la littérature antérieure, la thèse vise à identifier les facteurs déterminants de la performance sportive et financière listés dans CFP et à les comparer avec les déterminants des performances sportives et financières des CFP au Moyen-Orient.Cette thèse fournit d'autres preuves empiriques sur la relation entre la performance sportive et la performance financière dans les CFP listés. Le plus important est que les résultats de la thèse fournissent un nombre de facteurs déterminants qui affectent la performance sportive et financière dans les CFP. Parmi les résultats intéressants, on peut citer l’existence de facteurs similaires et différents entre les clubs de football européens et les clubs de football du Moyen-Orient. Cela semble être confirmé par le fait que le marché et les tournois et les règlements sont différents. De plus, l’impact des spectateurs est un résultat intéressant, dans lequel leur effet sur la performance financière est indirect, alors qu’il est direct sur la performance sportive. Cependant, la juste valeur du club est incertaine en raison du manque de divulgation et de détail des informations comptables. Nous suggérons donc d'améliorer la gouvernance d'entreprise pour améliorer la transparence et la responsabilité. De plus, la thèse suggère que la perspective de la gestion stratégique est un facteur important pour traiter la performance financière non durable des CFP, en particulier à long terme afin de mesurer la juste valeur du club. Cela a conduit à gagner en pertinence compte tenu de l’importance de la gestion stratégique dans les futures recherches universitaires. Ainsi, nous pouvons poser la question suivante: dans quelle mesure l’introduction en bourse est-elle durable dans les clubs de football professionnels?
In 1990s and 2000s many professional soccer (PSCs) clubs have been listed IPO in stock markets. The success of IPO in soccer markets, especially in the field of sports and financial performance is uncertain. Thus, number of empirical academic researches have been advocated to examine financial performance of IPO in these clubs. Such researches found financial performance of listed clubs is declined. Most of those researches indicate there is relationship between sports performance and financial performance in those listed clubs. However, researchers have not determine the factors of this phenomenon. To bridge this gap in the past literature, thesis aims to identify the determining factors of sports and financial performance in listed PSCs and to compare them with determinants of sports and financial performance of PSCs in Middle East.This thesis provides further empirical evidence on the relationship between sports and financial performance in listed PSCs. More importantly, results of thesis provide number of determining factors that affect sports and financial performance in PSCs. An interesting results, there are some similar and dissimilar factors between European soccer clubs and Middle east soccer clubs. This seemed to be confirmed by the fact that market and tournament and regulations are different. Furthermore, impact of spectators is interesting result, in which their effect on financial performance is indirect, while direct on sports performance. Yet, fair value of club is uncertain because lack of disclosure and detail accounting information. Thus, we suggest improving corporate governance to enhance transparency and accountability. Moreover, thesis suggest that strategic management perspective is important factor to treat unsustainable financial performance of PSCs, especially in long term in order to measure fair value of club. This lead to gain more relevance considering the importance of strategic management in future academic researches. Thus, we can raise the following question is to which extent IPO is sustainable in professional soccer clubs?
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4

Tatibouët, Jérémie. "Approche systématique basée sur fUML pour formaliser la sémantique d’exécution des profils UML." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112247.

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Les profils permettent de customiser UML pour un domaine particulier. Cette customisation se fait par l’ajout de concepts (stéréotypes) relatifs au domaine, l’ajout de contraintes sur ces concepts ainsi que la résolution de points de variation sémantiques. Il existe un processus établit et documenté dans l’état de l’art permettant de construire la syntaxe de ces langages basés sur UML. En revanche, ce processus ne couvre pas l’aspect formalisation de la sémantique et les propositions issues de l’état de l’art ne présentent pas d’approches systématiques pour traiter ce problème.La formalisation de la sémantique est un point essentiel de la construction d’un langage car elle permet de donner le sens des constructions syntaxiques. Pour être efficace, la formalisation de la sémantique d’un langage doit être menée conjointement à une action de normalisation. L’intérêt d’avoir une sémantique formelle et standard pour un langage est qu’elle permet aux modèles définis dans ce langage d’être exploités (analyse, exécution, simulation, etc.) de manière équivalente entre les outils. Cette équivalence permet aux utilisateurs d’observer des interprétations identiques d’un même modèle entre différents outils et donc d’avoir une compréhension commune du modèle et de la sémantique associée. Dans le contexte des profils, les actions de normalisations menées par l’OMG se concentrent exclusivement sur la syntaxe et la formalisation de la sémantique est négligée. Nous proposons de répondre à ce problème en nous appuyant sur les spécifications fUML et PSCS qui définissent une sémantique normative pour un sous-ensemble d’UML.Dans un premier temps, nous définissons deux méthodologies alternatives s’appuyant sur ces standards permettant de formaliser la sémantique d’exécution d’un profil UML. Dans la première méthodologie la sémantique d’exécution d’un profil est formalisée au niveau du modèle de domaine. La forme exécutable d’un modèle applicatif profilé est obtenue par transformation de modèle. Dans la seconde méthodologie, la sémantique est définie directement pour le profil. Le modèle qui la formalise est une extension du modèle sémantique de fUML/PSCS formalisée avec fUML. Les modèles sémantiques obtenus sont conformes à fUML ce qui les rend par construction exécutables et directement exploitables dans n’importe quel outil implantant les normes UML et fUML. Dans un deuxième temps, nous comparons nos approches sur la base de trois critères : l’effort de modélisation requis pour produire le modèle sémantique, la préservation de la sémantique de base d’UML définie par fUML/PSCS et la possibilité d’identifier rapidement les relations entre les stéréotypes et leurs sémantiques. Cette comparaison, nous permet de montrer la capacité de notre seconde méthodologie à prendre en compte des extensions clefs de la sémantique de base d’UML dans le contexte des profils. Ces éléments clefs sont : la délégation du contrôle, l’instanciation et les communications. L’ensemble de nos contributions ont été outillées dans le contexte de l’outil d’exécution de modèles MOKA qui est intégré au modeleur UML/SysML Papyrus
UML profiles enable the UML to be tailored to a particular domain. To do so, a profile adds domain specific concepts (i.e., stereotypes) and constraints to UML and disambiguates specific semantic variation points. The design process for abstract syntax of profiles is well documented in the literature. However, specification of the semantics is neglected. According to our researches, there are no proposals in the state-of-the-art that define a systematic approach to solve this problem.Semantic formalization is a key point of language design. It enables to formally define the meaning of syntactic elements. In order to be efficient, the formalization activity must be realized in parallel with a standardization activity. The interest to have a language with a formal standardized semantic is to enable models defined using this latter to be interpreted (analysis, execution, simulation) in equivalent way between tools implementing the semantics. This equivalence enables users to observe similar interpretations of the same model between different tools and therefore to have a shared understanding of this model and the associated semantic.In the context of UML profiles, normalization activities leaded by the OMG are focused on the syntax. The semantic formalization aspect is neglected. We propose to address this problem by relying on fUML and PSCS OMG (Object Management Group) specifications. These standards formalize execution semantics for a subset of UML (classes, composite structures, and activities).Firstly, we define two methodologies relying on these standards to formalize execution semantics of UML profiles execution semantics. The first methodology defines the execution semantics for the domain model underlying the profile. The executable form of an applicative model defined using the profile is obtained by model transformation. In the second methodology, semantics are defined directly for the profile by extending the semantic model of fUML/PSCS using fUML. By being conform to fUML, the semantic model is by construction executable and can be directly used in any tools implementing the UML and fUML standards.Secondly, we compare our approaches against the following criteria: the modelling effort required to build the semantic model, the capability of the methodology to preserve the UML semantics (i.e., the one defined by fUML/PSCS) and the capability to identify clearly the relationships between the stereotypes and their semantics. This comparison enables us to demonstrate the capacity of the second methodology to define key extensions of the UML semantics in the context of a profile. These latter are: the control delegation, the instantiation, and the communications. The contributions have been implemented in our model execution framework Moka which is integrated in the open-source UML/SysML modeling tool Papyrus
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5

Quinaud, Manuelle. "Étude structurale et fonctionnelle de PscE : PscF : PscG? un hétérotimère nécessaire à la biogenèse de l'aiguille de sécretion de type III de Pseudomonas aeruginosa." Grenoble 1, 2007. http://www.theses.fr/2007GRE10138.

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Le système de sécrétion de type III est présent chez plusieurs pathogènes à Gram négatif chez qui cette véritable nanomachine est impliquée dans le transport de molécules de virulence directement des bactéries vers le cytoplasme des cellulescible. Ce système de sécrétion est composé d'une base ancrée dans la membrane bactérienne et d'une structure creuse en forme d'aiguille qui pointe vers l'extérieur de la bactérie. Pseudomonas aeruginosa, bactérie dont l'aiguille de sécrétion de type III est étudiée dans cette thèse, est responsable de nombreuses maladies nosocomiales ainsi que d'infections chez les patients atteints de mucoviscidose. Dans le cytoplasme bactérien, la protéine PscF qui forme l'aiguille de type III chez P. Aeruginosa est stabilisée avant sa sécrétion par 2 chaperonnes distinctes; PscE et PscG. Ceci est nécessaire à la fonctionnalité du système de sécrétion de type III. La structure cristallographique à 2. 0 A de résolution du complexe hétérotrimérique PscE:PscF55-85_PscG révèle que le domaine C-terminal de la protéine de l'aiguille B PscF, impliqué dans le processus de polymérisation, est enfoui dans une cavité hydrophobe de la protéine PscG. La rupture des interactions spécifiques entre PscG et PscF entraîne une forte baisse de la cytotoxicité de la bactérie envers une lignée de macrophages, ce qui indique que cet hétérotrimère essentiel, qui possède des homologues chez une grande variété de pathogènes, est une cible thérapeutique attractive pour le développement de nouveaux médicaments
Type III secretion systems are found in several Gram-negative bacteria. These nanomachines are involved in the transport of virulence effectors directly into the cytoplasm of Target cells. Pseudomonas aeruginosa, whose type III secretion needle is studied here, is the causative agent of a large number of nosocomial and chronic infections in cystic fibrosis patients. This system is composed of a base anchored in the double bacterial membrane and a hollow needle formed by a single polymerized protein (PscF in Pseudomonas aeruginosa). Within the bacterial cytoplasm, PscF requires two distinct chaperones for stabilisation before its secretion, without which the entire system is nonfunctionnal. The 2. 0 A X-ray crystal structure orthe PscE:PscF55-85 :PscG ternary complex reveals that the C-terminus of the needle protein PscF, which is essential for needle polymerisation, is engulfed within the hydrophobic groove of the TPR-like molecule PscG. This indicates that the macromolecular scaffold necessary to stabilize the needle protein is totally distinct from T chaperoned complexes between pilus- or flagellum- forming molecules. Disruption of specific PscG:PscF interactions leads to impairement of bacterial cytotoxicity toward macrophages, indicating that This essential heterotrimer, which possesses homologs in a wide variety of pathogens, is an attractive therapeutic Target for the development of novel drugs
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Hambsch, Mike, Qianqian Lin, Ardalan Armin, Paul L. Burn, and Paul Meredith. "Efficient, monolithic large area organohalide perovskite solar cells." Royal Society of Chemistry, 2016. https://tud.qucosa.de/id/qucosa%3A36282.

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Solar cells based on organohalide perovskites (PSCs) have made rapid progress in recent years and are a promising emerging technology. An important next evolutionary step for PSCs is their up-scaling to commercially relevant dimensions. The main challenges in scaling PSCs to be compatible with current c-Si cells are related to the limited conductivity of the transparent electrode, and the processing of a uniform and defect-free organohalide perovskite layer over large areas. In this work we present a generic and simple approach to realizing efficient solution-processed, monolithic solar cells based on methylammonium lead iodide (CH₃NH₃PbI₃). Our devices have an aperture area of 25 cm² without relying on an interconnected strip design, therefore reducing the complexity of the fabrication process and enhancing compatibility with the c-Si cell geometry. We utilize simple aluminum grid lines to increase the conductivity of the transparent electrode. These grid lines were exposed to an UV-ozone plasma to grow a thin aluminum oxide layer. This dramatically improves the wetting and film forming of the organohalide perovskite junction on top of the lines, reducing the probability of short circuits between the grid and the top electrode. The best devices employing these modified grids achieved power conversion efficiencies of up to 6.8%.
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De, Canditiis Bartolomeo. "3D characterization of multi-segmented HPGe detectors : simulation and validation of the PSCS technique and its application for different energies with a 152 Eu source." Thesis, Strasbourg, 2020. http://www.theses.fr/2020STRAE008.

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Les ensembles de détecteurs de rayon gamma de nouvelle génération, tel AGATA, utilisent des détecteurs multi-segmentés de germanium hyper-pur dans les expériences de physique nucléaire pour lesquelles une grande résolution et efficacité sont demandées. Ces caractéristiques sont obtenues par l’application des techniques d'analyse des formes d'impulsion et de tracking des rayons gamma. Ces dernières demandent une caractérisation volumétrique des détecteurs. À cet effet, l'IPHC a développé une table de scan qui utilise la technique Pulse Shape Comparison Scan (PSCS). Des simulations sont réalisées pour quantifier la précision de la technique PSCS et pour la valider. Elles sont appliquées sur un détecteur planaire pixelisé 3x3 et sur un détecteur symétrique d'AGATA de type S. La méthode est testée avec plusieurs énergies de rayons gamma et diverses statistiques d'entrée. Des scans réels sont aussi entrepris sur les deux détecteurs, qui sont totalement caractérisés. En particulier, un scan réalisé pour la première fois avec une source de rayons gamma de 152Eu, prouve la validité de certaines hypothèses sur lesquelles repose la technique de tracking
New generation gamma-ray detectors arrays, such as AGATA, employ multi-segmented high purity germanium detectors in experiments of nuclear physics that require high resolution and efficiency which are obtained thanks to the application of pulse-shape analysis and gamma-ray tracking. These techniques require full volume characterization of the position sensitive detectors. The IPHC developed a scanning table that uses the Pulse Shape Comparison Scan (PSCS) technique to perform this task. Simulations are performed to quantify the accuracy of the PSCS and to validate it.They are applied on a pixelated 3x3 planar detector and a symmetrical S-type AGATA detector. The method is tested with different gamma-ray energies and input statistics. Several real scans are performed as well on both detectors, which are fully characterized. In particular a scan with agamma-ray source of 152Eu, the first ever done, prove some assumptions on which the tracking technique is based
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Bala, Masud. "Effects of IFRS adoption on the financial statements of Nigerian listed entities : the case of oil and gas companies." Thesis, Abertay University, 2015. https://rke.abertay.ac.uk/en/studentTheses/2a81c014-18a6-4372-90c8-985f6ad8e0d3.

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On 28 July 2010, the Nigerian Federal Executive Council approved January 1, 2012 as the effective date for the convergence of Nigerian Statement of Accounting Standards (SAS) or Nigerian GAAP (NG-GAAP) with International Financial Reporting Standards (IFRS). By this pronouncement, all publicly listed companies and significant public interest entities in Nigeria were statutorily required to issue IFRS based financial statements for the year ended December, 2012. This study investigates the impact of the adoption of IFRS on the financial statements of Nigerian listed Oil and Gas entities using six years of data which covers three years before and three years after IFRS adoption in Nigeria and other African countries. First, the study evaluates the impact of IFRS adoption on the Exploration and Evaluation (E&E) expenditures of listed Oil and Gas companies. Second, it examines the impact of IFRS adoption on the provision for decommissioning of Oil and Gas installations and environmental rehabilitation expenditures. Third, the study analyses the impact of the adoption of IFRS on the average daily Crude Oil production cost per Barrel. Fourth, it examines the extent to which the adoption and implementation of IFRS affects the Key Performance Indicators (KPIs) of listed Oil and Gas companies. The study further explores the impact of IFRS adoption on the contractual relationships between Nigerian Government and Oil and Gas companies in terms of Joint Ventures (JVs) and Production Sharing Contracts (PSCs) as it relates to taxes, royalties, bonuses and Profit Oil Split. A Paired Samples t-test, Wilcoxon Signed Rank test and Gray’s (Gray, 1980) Index of Conservatism analyses were conducted simultaneously where the accounting numbers, financial ratios and industry specific performance measures of GAAP and IFRS were computed and analysed and the significance of the differences of the mean, median and Conservatism Index values were compared before and after IFRS adoption. Questionnaires were then administered to the key stakeholders in the adoption and implementation of IFRS and the responses collated and analysed. The results of the analyses reveal that most of the accounting numbers, financial ratios and industry specific performance measures examined changed significantly as a result of the transition from GAAP to IFRS. The E&E expenditures and the mean cost of Crude Oil production per barrel of Oil and Gas companies increased significantly. The GAAP values of inventories, GPM, ROA, Equity and TA were also significantly different from the IFRS values. However, the differences in the provision for decommissioning expenditures were not statistically significant. Gray’s (Gray, 1980) Conservatism Index shows that Oil and Gas companies were more conservative under GAAP when compared to the IFRS regime. The Questionnaire analyses reveal that IFRS based financial statements are of higher quality, easier to prepare and present to management and easier to compare among competitors across the Oil and Gas sector but slightly more difficult to audit compared to GAAP based financial statements. To my knowledge, this is the first empirical research to investigate the impact of IFRS adoption on the financial statements of listed Oil and Gas companies. The study will therefore make an enormous contribution to academic literature and body of knowledge and void the existing knowledge gap regarding the impact and implications of IFRS adoption on the financial statements of Oil and Gas companies.
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Duffin, Heidi R. "A Qualitative Method for Dynamic Transport Selection in Heterogeneous Wireless Environments." Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd546.pdf.

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Zhang, Jueman (Mandy). "Making online HIV/AIDS PSAs more effective." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2009. http://wwwlib.umi.com/cr/syr/main.

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Causey, Charles Lawson. "The Effects of PSAS on Trust in Romantic Relationships." W&M ScholarWorks, 2006. https://scholarworks.wm.edu/etd/1539720284.

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Saunders, Paige F. "Targeting Functions: A New Approach to Anti-Smoking PSAs." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1308241861.

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Wang, Linghan. "Race Moderates the Motivational Processing of Anti-Smoking PSAs." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397734531.

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Nosrati, Kamyar. "Substation Reliability Analysis Using PSS/E." Thesis, KTH, Electromagnetic Engineering, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48118.

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This report documents an MSc Thesis work of sub-transmission reliability study using PSS/Eperformed at Vattenfall. The network that is examined in this thesis is a sub-transmission network.Vattenfall Distribution Sweden is going to invest and rebuild the network in their 70 and 130 kVmeshed sub transmission network. To invest and rebuild in a network is very expensive. The gridowners want a reliable system that has a high reliability at a low cost.The main focus in this thesis is to examine different substation layouts. Calculating the failureintensities and unavailability for the different substation layouts gives the opportunity to do a life cyclecosts (LCC) on the different substations. With help of LCC calculations it is possible to find thesubstation that gives the lowest cost during a life time. Choosing right equipment in the grid will helpthe Vattenfall network company lower their equipment costs.The thesis work consists of mainly three parts as follows. Network modeling in PSS/EA subset of the existing sub transmission network was used in the project. This subset was taken outfrom the complete network model and modeled in PSS/E. Validation of PSS/E reliability modulesPSS/E reliability modules were new and have not been used earlier by the Vattenfall networkcompany. To be sure that the program calculates correctly a validation was performed. The main focusof the validation has been in looking if the program calculates the interrupted power correctly. Reliability analysis of different substation layoutsFor each of the substation layout the reliability was calculated. On component level (e.g. breaker,disconnector) different types of configuration were studied. To find out the best layout from aneconomical point of view a LCC calculation was also performed.The LCC calculation on the different substation layouts showed that the investment costs affect theresult very much. When the active power through the substation is low it is preferred to use asubstation that has low investment costs. At active power that is 30 MW or higher it is preferred to usethe substation with higher reliability (having higher investment cost). The result shows that using acombined breaker and disconnector instead of circuit breaker could lower the failure intensity andunavailability of substations.
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Kowalkowski, Christian, and Daniel Kindström. "Value visualization strategies for PSS development." Linköpings universitet, Industriell marknadsföring och industriell ekonomi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-59921.

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The concept of value visualization is concerned with the way that firms communicate and demonstrate the value of their product-service systems (PSS), both internally and externally. In this chapter, a visualization strategy framework for PSS development is proposed. It is particularly tailored for industrial companies that are strategically shifting from selling products to becoming providers offering PSS. Value visualization strategies have traditionally focused on external sales activities. However, companies need to have a broader approach to visualization in all PSS development phases, as well as including different visualization techniques. Furthermore, different visualization strategies are needed for each particular development stage of the PSS. Companies need be able to make use of several different visualization strategies, depending on the actual content of the product-service system and its position in the development process. Whereas the product development process is rather heavy at the back, successful PSS development projects with high levels of service need to be heavy at the front (that is, they need to not only develop the system but also ensure its rollout). Examples are provided from eight market-leading companies in different industries, each of which are undertaking a strategic shift from identifying as product sellers toward becoming providers offering PSS. To conclude, value visualization has become vital for winning new contracts and retaining existing ones. It is therefore a strategic resource that managers need to pay attention to, and continuously develop, in order to compete with PSS offerings.

Original Publication: Christian Kowalkowski and Daniel Kindström, Value visualization strategies for PSS development, 2009, Chapter in: Introduction to Product/Service-System Design, 159-182, Eds T. Sakao and M. Lindahl. http://dx.doi.org/10.1007/978-1-84882-909-1_8 Copyright: Springer http://www.springerlink.com/

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Qie, Lili. "Performance Improvement of Latex-based PSAs Using Polymer Microstructure Control." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19727.

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This thesis aims to improve the performance of latex-based pressure-sensitive adhesives (PSAs). PSA performance is usually evaluated by tack, peel strength and shear strength. Tack and peel strength characterize a PSA’s bonding strength to a substrate while shear strength reflects a PSA’s capability to resist shear deformation. In general, increasing shear strength leads to a decrease in tack and peel strength. While there are several commercial PSA synthesis methods, the two most important methods consist of either solvent-based or latex-based techniques. While latex-based PSAs are more environmentally compliant than solvent-based PSAs, they tend to have much lower shear strength, at similar tack and peel strength levels. Therefore, the goal in this thesis was to greatly improve the shear strength of latex-based PSAs at little to no sacrifice to tack and peel strength. In this study, controlling the polymer microstructure of latexes or their corresponding PSA films was used as the main method for improving the PSA performance. The research was sub-divided into four parts. First, the influence of chain transfer agent (CTA) and cross-linker on latex polymer microstructure was studied via seeded semi-batch emulsion polymerization of butyl acrylate (BA) and methyl methacrylate (MMA). Three techniques were used to produce the latexes: (1) adding CTA only, (2) adding cross-linker only, and (3) adding both CTA and cross-linker. It was found that using CTA and cross-linker simultaneously allows one to expand the range of latex microstructural possibilities. For example, latexes with similar gel contents but different Mc (molecular weight between cross-links) and Mw (molecular weight of sol polymers) could be produced if CTA and cross-linker concentration are both increased. However, for the corresponding PSAs with similar gel contents, the relationship between their polymer microstructure and performance was difficult to establish as almost all of the medium and high gel content PSAs showed very low tack and peel strength as well as extremely large shear strength readings. In the second part of this thesis, in order to improve the tack and peel strength of medium and high gel content PSAs, the monomer composition and emulsifier concentration were varied. It was found that changing the monomer mixture from BA/MMA to BA/acrylic acid (AA)/2-hydroxyethyl methacrylate (HEMA) while simultaneously decreasing emulsifier concentration dramatically improved the corresponding PSAs’ shear strength as well as tack and peel strength. The addition of polar groups to the PSA increased its cohesive strength due to the presence of strong hydrogen bonding; meanwhile, PSA films’ surface tension increased. In the third part, two series of BA/AA/HEMA latexes were generated by varying the amounts of CTA either in the absence or presence of cross-linker. The latexes produced in the absence of cross-linker exhibited significantly larger Mc and Mw compared to their counterparts with similar gel contents prepared with cross-linker. The PSAs with the larger Mc and Mw showed much larger shear strengths due to improved entanglements between the polymer chains. In the final part of the thesis, the performance of the BA/AA/HEMA PSAs was further improved by post-heating. Compared with original latex-based PSAs with similar gel contents, heat-treated PSAs showed not only significantly improved shear strengths, but also much larger tack and peel strengths. The different shear strengths were related to the PSAs’ gel structures, which were discrete in the original PSAs but continuous in the heat-treated PSAs. The improved tack and peel strengths were related to the PSA films’ surface smoothness. During the post-heating process, the PSA polymer flowed, resulting in much smoother surfaces than the original PSA films. In addition, the effect of post-heating was related to the polymer microstructure of the untreated PSAs. Decreasing the amount of very small or very big polymers or simultaneously increasing Mc and Mw could lead to post-treated PSAs with significantly better performance. Moreover, it was found that by optimizing the polymer microstructure of the original latex-based PSAs, it was possible to obtain a treated PSA with similar or even better performance than a solvent-based PSA with similar polymer microstructure. Our original objective was surpassed: in two cases, not only was shear strength greatly improved, but so were tack and peel strength due to the simultaneous modification of PSA bulk and surface properties.
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17

Canavezes, Alexandre Gonzalez da Rocha Silva. "The topology of the density of the universe using PSCz." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314346.

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18

Feng, Yamiao. "Factors influencing college students’ attitude toward PSAs for recruiting volunteers." Thesis, Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-8687.

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Background: Public service advertising in China just has two decades years of history and media used for public service advertising mainly focus on print advertising. Compared to commercial advertising, public service advertising is not mature in China whatever in the forms, content variety or media. Chinese internet users have increased rapidly in recent years, so in this situation, the development of online PSAs is especially important. While many researches focus on print media, few are about PSAs on internet. The money of charity organization spent on PSAs is rare, because the donators want their donation spent on important place. So the quality of PSAs is important to attract people’s attention.Purpose: The purpose of this thesis is to investigate the factors influencing college students’ attitude toward online public service advertising for recruiting volunteers.Method: A quantitative method is taken in this thesis. The primary data are collected through questionnaire and the sample is college students in university in Shanghai for science and technology. The secondary data come from mainly E-library, E-journal and books. To analyze the data, hypothesis testing method is used and SPSS is used as statistical analysis tool.Conclusions: Entertainment, informativeness, irritation, credibility and advertising value these factors from Ducoffe’s model are applied to the research on attitude toward PSAs. The result shows that factors of entertainment, informativeness and advertising value have positive influence on college students’ attitude, while factors of irritation and credibility don’t have influence on college students’ attitude toward volunteer recruitment PSAs, thus they have a nearly neutral attitude. Entertainment and informativeness have significant correlation with advertising value separately, and this situation can also be applied to attitude toward PSAs. Advertising value has significant correlation with attitude toward PSAs. So the Ducoffe’s model is not totally appropriate for the research on attitude toward PSAs.
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Neves, Aline da Silva Boschi Martins. "Evid?ncias de Validade da PSS-10 e PSS- 14: Estudo com An?lise Fatorial e de Rede." Pontif?cia Universidade Cat?lica de Campinas, 2018. http://tede.bibliotecadigital.puc-campinas.edu.br:8080/jspui/handle/tede/1093.

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Stress is one of the constructs emphasized when evaluating the health-disease process. However, because it is a latent variable, specific instruments are needed to measure it. The Perceived Stress Scale (PSS) is an instrument that has been used to assess the perception of stress in the last month. Despite numerous validations in several countries, their psychometric properties have not been consensual. The main objective of this work was to investigate the internal structure of the PSS-10 and PSS-14 versions, through exploratory factorial (AFE) and network analysis. Thus, two studies were carried out: in Study I, PSS-10 and PSS-14 were analyzed through AFE and, in study II, the scales were analyzed through network analysis. We used: a) the PSS-10 with a sample composed of 686 participants, being 175 (27.3%) men and 466 (72.7%) women (n = 641), with a mean age of 33.9 SD = 11.3) years, ranging from 18 to 73 (n = 632); and (b) the PSS-14 was answered by 690 participants, of which 304 (44.1%) were men and 386 (55.9.7%) were women, with a mean age of 34.72 (SD = 12, 56), with a range of 18 to 65. In both analyzes, the psychometric properties of PSS-10 and PSS-14 were shown to be reliable and confirmed the two-dimensional structure of distress and coping. Also, the network analysis allowed to explore the PSS in the Brazilian context, allowing new association patterns to emerge from the analyzed samples. And, even AFE being a widely used technique in the construction and evaluation of psychometric tests, network analysis has shown to be a promising and much more comprehensive tool at the level of the symptom, accommodating the numerous processes of psychological constructions. In this study, the network analysis showed how the perception of control influences the outcome of stress. Thus, in addition to providing evidence of validity of the PSS-10 and PSS-14, this study demonstrated how much the network analysis has to contribute in the psychology and health area.
O estresse ? um dos construtos enfatizados quando se avalia o processo sa?de- doen?a. No entanto, por ser uma vari?vel latente, instrumentos espec?ficos s?o necess?rios para mensur?-lo. A Escala de Estresse Percebido (Perceived Stress Scale - PSS) ? um instrumento que tem sido utilizado para avaliar a percep??o do estresse no ?ltimo m?s. Apesar de in?meras valida??es em diversos pa?ses, suas propriedades psicom?tricas n?o t?m sido consensuais. O objetivo principal deste trabalho foi investigar a estrutura interna das vers?es PSS-10 e PSS-14, por meio de an?lise fatorial explorat?ria (AFE) e de rede. Assim, dois estudos foram realizados: no Estudo I, a PSS-10 e a PSS-14 foram analisadas atrav?s da AFE e, no estudo II, analisaram-se as escalas por meio da an?lise de rede. Foram utilizadas: a) a PSS-10 com uma amostra composta por 686 participantes, sendo 175 (27,3%) homens e 466 (72,7%) mulheres (n = 641), com m?dia de idade de 33,9 (SD = 11,3) anos, com amplitude de 18 a 73 (n = 632); e b) a PSS-14 que foi respondida por 690 participantes, dos quais 304 (44,1%) s?o homens e 386 (55,9,7%), mulheres, com m?dia de idade de 34,72 (SD = 12,56) anos, com amplitude de 18 a 65. Nas duas an?lises, as propriedades psicom?tricas da PSS-10 e PSS-14 demonstraram-se confi?veis e confirmaram a estrutura bidimensional de distress e coping. Ainda, a an?lise de rede permitiu explorar a PSS no contexto brasileiro, permitindo que novos padr?es de associa??o emergissem das amostras analisadas. E, mesmo a AFE sendo t?cnica muito utilizada na constru??o e avalia??o de testes psicom?tricos, a an?lise de rede demonstra ser uma ferramenta promissora e muito mais abrangente no n?vel do sintoma, acomodando os numerosos processos das constru??es psicol?gicas. Neste estudo, a an?lise de rede evidenciou o quanto a percep??o de controle influencia no desfecho do estresse. Assim, al?m de fornecer evid?ncias de validade da PSS-10 e PSS-14, este estudo demonstrou o quanto ? an?lise de rede tem a contribuir no ?mbito da psicologia e na ?rea da sa?de.
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Ilis, Lars. "Implementering av en PSS i Trängslets kraftstation." Thesis, Uppsala universitet, Elektricitetslära, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-209381.

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The purpose of this master thesis is to implement and validate a Power System Stabilizer (PSS) to a generator at Trängslet hydropower station in Dalarna, Sweden. Problems with local rotor oscillations can occur at the hydropower station when power is transferred on a new power line (130 kV) from Northern to Southern part of Dalarna. To ensure good operation properties on this power line Fortum Generation AB and Fortum Distribution AB wants to activate a PSS on a generator. There have been investigations in which situations and what equipment that contributes to rotor oscillations. When this is known the PSS is tuned to damp these oscillations by choosing a good set of parameters. The most important parameters for good performance are to choose amount of gain and phase compensation. The chosen set of parameters are verified with a test in the power station to ensure that the task is completed. Test results shows that the magnitude of the first swing in rotor oscillation is almost the double than what PSS/E shows, but good correlation five seconds after initialization of the disturbance. The inherent dampening performance of the generator is much better in reality than in simulation. The chosen set of parameters contributes to rotor oscillation dampening in a magnitude approximately equal to simulation results in PSS/E, why the conclusion has been made that the implementation of the PSS is successful. There has also been made simulations with different power outputs and amount of generators synchronized whose results shows that damping is greatly increased with the chosen PSS.
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21

Sharpe, Jacob Christopher. "PSC-z determination of the local flow." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311931.

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22

Mehal, Wajahat Z. "Pathogenetic factors in primary sclerosing cholangitis (PSC)." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386583.

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23

Marques, Caio Augusto Nunes. "Framework para definir modelos de processos específicos de desenvolvimento de PSS." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18156/tde-25092018-110733/.

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As empresas historicamente voltadas à produção de bens manufaturados têm enfrentado uma série de desafios ao longo das últimas décadas. Notadamente o acirramento da competitividade nos diversos mercados tem contribuído para com que diversos produtos sejam transformados em commodities com qualidade e desempenho similares. A disputa entre os players deixa de ser baseada em liderança tecnológica e tende a se resumir à busca por menores custos de produção. Paralelamente, cresce a consciência em diversos atores da sociedade em relação às questões ambientais e, consequentemente, a pressão sobre as indústrias para que contribuam com a criação de uma sociedade mais sustentável. A criação de pacotes que combinam produtos e serviços para entregar valor em uso ou via realização de uma função é uma estratégia que tem sido estudada para contornar os desafios citados. A criação e oferta de um Sistema Produto-Serviço (PSS – do inglês Product-Service System) por uma empresa de manufatura tem potencial para contribuir nas três perspectivas da sustentabilidade, mas traz alguns desafios. O desenvolvimento de produtos e de serviços deve ser feito de forma integrada, considerando seus relacionamentos e, muitas vezes, o modelo de negócios da empresa acaba sendo modificado. Para contornar os desafios relacionados ao desenvolvimento, existem modelos genéricos de processo de desenvolvimento de PSS propostos para que as empresas definam seus próprios modelos específicos. Esses modelos foram propostos para diferentes contextos de desenvolvimento e normalmente carregam os vieses de seus autores, apresentando pontos fortes e limitações. O presente trabalho tem como objetivo propor um framework para definir modelos de processos específicos de desenvolvimento de Sistemas Produto-Serviço. Para tanto este trabalho utiliza o paradigma do método hipotético-dedutivo e a abordagem metodológica DRM (Design Research Methodology). Os métodos de pesquisa utilizados são: painel de especialistas, linguística de corpus e semântica de frames, focus group, estudo de caso, revisão bibliográfica sistemática e análise de conteúdo. Foi possível obter três contribuições inéditas: um conjunto de 310 atividades-síntese; a análise de 15 modelos de processo de desenvolvimento de PSS; e o framework propriamente dito. As duas primeiras são contribuições à teoria. As atividades-síntese correspondem a todas as atividades de desenvolvimento de PSS previstas nos modelos de processo de desenvolvimento de PSS disponíveis na literatura, constituindo seu estado da arte. A análise dos modelos de processo evidenciou objetivamente os seus diferentes perfis, com cada modelo priorizando determinadas categorias de atividades em detrimento de outras. O framework criado foi testado em dois projetos de desenvolvimento de PSS em duas startups, e constitui uma contribuição aos praticantes nas indústrias, que podem utilizá-lo para definir seus modelos de processos específicos de desenvolvimento de PSS a partir de uma base mais abrangente de atividades que em qualquer um dos 15 modelos genéricos analisados.
Companies historically focused on the production of manufactured goods have faced a number of challenges over the past few decades. Notably, the intensification of competitiveness in the various markets has contributed to the transformation of various products into commodities of similar quality and performance. The dispute between players ceases to be based on technological leadership and tends to be limited to the search for lower production costs. At the same time, rises the awareness of various actors in society regarding environmental issues and, consequently, the pressure on industries to contribute to the creation of a more sustainable society. The creation of products and services bundles to deliver value in use or through the performance of a function is a strategy that has been studied to overcome the aforementioned challenges. The creation and offering of a Product-Service System (PSS) by a manufacturing company has the potential to contribute to the three perspectives of sustainability, but it also poses some challenges. The development of products and services must be done in an integrated way, considering their relationships and, often, the company\'s business model has to be changed. In order to overcome the development challenges, there are generic PSS development process models proposed for companies to define their own specific models. These models have been proposed for different development contexts and usually carry the biases of their authors, thus presenting strengths and limitations. The present work aims to propose a framework for defining specific process models to develop Product-Service Systems. For this, this work uses the paradigm of the hypothetical-deductive method and the DRM (Design Research Methodology) methodological approach. The research methods used are: experts\' panel, corpus linguistics and frame semantics, focus group, case study, systematic literature review and content analysis. It was possible to obtain three unpublished contributions: the set of 310 synthesis activities; the analysis of the 15 PSS development process models; and the framework itself. The first two are contributions to theory. The synthesis activities correspond to all the PSS development activities prescribed by the PSS development process models available in the literature, constituting its state of the art. The analysis of the process models objectively evidenced their different profiles, with each model prioritizing certain categories of activities in comparison to others. The framework created was applied to two PSS design project in two startups, being a contribution to practitioners in industries that can use it to define their specific PSS development processes models from a broader base of activities than in any of the 15 generic models analyzed.
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Aspinall-O'Dea, Mark Kevin. "An investigation of the PsbS protein isolated from spinach chloroplast membranes." Thesis, University of Sheffield, 2005. http://etheses.whiterose.ac.uk/14485/.

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Dissipation of excess light energy in plant photosynthetic membranes plays an important role in the response of plants to the environment, providing short-term balancing between the intensity of sunlight and photosynthetic capacity. The carotenoid zeaxanthin and the photosystem Il subunit PsbS play vital roles in this process, but the mechanism of their action is largely unexplained. This thesis reports a novel procedure for the extraction of the PsbS protein from spinach thylakoids, including a detailed account of the developmental process and characterisation of the isolated protein. The ability of the PsbS protein to bind xanthophyll cycle carotenoids in vitro was assessed, leading to the observation that the isolated protein was able to bind exogenous zeaxanthin, the binding resulting in a strong red shift in the absorption spectrum, and the appearance of characteristic features in the resonance Raman spectrum and a distinct circular dichroism spectrum, indicating pigment-protein, as well as specific pigmentpigment, interaction. A strong shift in the absorption spectrum of PsbS phenylalanine residues after zeaxanthin binding was observed. It is concluded that zeaxanthin binding to PsbS is the origin of the well known energy dissipation-related 535-nm absorption change. The ability of this PsbS-zeaxanthin complex to affect the rate of chlorophyll fluorescence quenching of the major LHcn antenna protein is detailed, revealing an increase in the rate of quenching, whilst the magnitude of quenching remained constant. The altered properties of zeaxanthin and PsbS after in vitro reconstitution and their subsequent effect on LHCnb provide the first direct indication about how they regulate energy dissipation.
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Dennison, Fraser. "Analysis of PSC Formation using Parcel Temperature Histories." Thesis, University of Canterbury. Physics and Astronomy, 2013. http://hdl.handle.net/10092/7872.

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Polar Stratospheric Clouds (PSCs) are composed of H₂SO₄/HNO₃/H₂O aerosols called supercooled ternary solution (STS), solid nitric acid trihydrate (NAT) particles and ice particles. These clouds require the low temperatures found in the polar regions of the lower stratosphere to occur. PSCs are important due to the critical role they play in the destruction of ozone over the poles. The role of PSCs in ozone destruction has been understood since the 1980’s however the mechanisms involved in PSC formation, particularly NAT formation, is still not well understood. Typically formation of PSCs in climate models is handled by using a temperature threshold as a proxy. A commonly used threshold is the equilibrium temperature for the existence of NAT, TNAT ; however when the area with temperatures below TNAT are compared with observations of PSC it is found that this measure significantly over-estimates the abundance of PSC. This research uses back trajectories stemming from the site of PSC observations to investigate the effect that the temperature history has on PSC formation. The trajectories are calculated using a simple Lagrangian model on an isentropic surface. The observational PSC data is obtained from the CALIOP (Cloud Aerosol Lidar with Orthogonal Polarization) instrument, which is from the CALIPSO (Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observations) mission launched in 2006. The CALIOP data used in this research is taken from the June to September period from the years 2007-10 and for latitudes between -55° and -82°S, and totals in excess of 7 million individual measurement profiles, a four day back trajectory is calculated for each observation along the 450 K isentropic level. Temperature and wind data is from the MERRA (Modern Era Retrospective-analysis for Research and Applications) reanalysis and H₂O and HNO₃ concentrations (required for calculating equilibrium temperatures) are from Earth Observing System (EOS) Aura Microwave Limb Sounder (MLS) version 3.3. It was found that different PSC types had different characteristics in their temperature histories. The mean temperature history associated with ice observations cooled by around 3 K over the previous 24 hours to slightly below the water ice frost point at the time of observation. However, in trajectories associated with the presence of NAT the temperature has on average stayed 4-5 K below TNAT for the entire four days of the trajectory. Based on these findings and theories of PSC formation, a system for predicting PSC occurrence based on the temperature histories is proposed. This system provides a better approximation for the total extent of PSC occurrence than the TNAT threshold. The average area covered by PSC on the 450 K level over the period examined as observed by CALIOP was 7.6 million km² while the area predicted by the temperature histories was 8.6 million km² as compared to 20.4 million km² with temperatures below TNAT. The average geographical coverage of the different PSC types is reasonably well replicated by the temperature history classification; however, the ability to discriminate between different PSC types based on individual temperature histories is somewhat limited.
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Axelsson, Daniel, and Daniel Olsson. "Utvärdering av olika dynamiska lastmodeller i PSS/E." Thesis, Högskolan Väst, Avdelningen för Industriell ekonomi, Elektro- och Maskinteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-11630.

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Examensarbetet har utförts på uppdrag åt Vattenfall Eldistribution AB.  Syftet med att arbetet har varit att skapa förståelse för dynamiska lastmodeller och klargöra hur de fungerar och hur de kan användas i PSS/E. Målen har varit att utföra simuleringar på kortslutningar och motorstart för två lastmodeller. Även beskrivning av grundprinciperna för asynkronmaskinen ingår för att få en koppling mellan simulering och teori. Asynkronmaskinens teori innehåller information om induktion och strömkrafter som är de grundläggande begreppen för asynkronmotorn. Det innehåller även sambanden mellan moment, varvtal, ström och spänning samt beskrivning av motorns ekvivalenta schema. Programmet IMD är ett program som tillhör PSS/E och har använts för att skapa modellen för asynkronmotorn som använts för simuleringarna. Vid utförande av simuleringarna har instruktioner från handledaren använts och även instruktioner från PSS/Es manualer. Simuleringarna har körts på två av PSS/Es inbyggda lastmodeller, en generell lastmodell och en modell för asynkronmotorer. Kortslutning har simulerats på båda modellerna och motorstart har simulerats med modellen för asynkronmaskiner. Kortslutning har simulerats med två olika feltider 0,15 och 0,4 sekunder, motorstart har simulerats med två olika storlekar på transformator 1,5 och 3,0 MVA och även tre olika tröghetstidskonstanter, 0,7, 1,0 och 1,5 MWs/MVA har använts. Vid kortslutning orsakar längre feltid större strömmar och längre återhämtningstid för båda lastmodeller. Vid motorstart påverkar storleken på transformatorn, i MVA, och tröghetstidskonstanten tiden för motorns startförlopp. Större transformator innebär kortare startförlopp på grund av minskat spänningsfall. Större tröghetstidskonstant innebär längre startförlopp.  Är man enbart intresserad av själva spänningssänkningens storlek och inte själva förloppet kan motorns startadmittans användas.
This bachelor’s thesis has been performed for Vattenfall Eldistribution AB. The purpose of this work has been to create understanding of dynamic load models and clarify how they function and how they can be used. The aim has been to perform simulations on short circuits and motor starts for two different load models. A part of the work is also to describe the basic principles of the induction motor to create a connection between simulation and theory. The theory of the induction motor contains information about the electric induction that is the basic principle of the induction machine. It also contains the correlations between torque, speed, current and voltage and also a description of the equivalent electric circuit. The IMD program is a program connected to PSS/E and it has been used to create the model for the induction motor that has been used for the simulations. The simulations have been based on instructions from the advisor and instructions from the PSS/E manuals. Simulations have been run with two of the built-in load models in PSS/E, one general load model and one model for induction motors. Short circuits have been simulated on both models and motor starts on the induction motor model. Short circuits have been simulated with two different fault durations 0.15 and 0.4 seconds. Motor starts have been simulated with two different transformer sizes 1.5 and 3.0 MVA and three different values of the inertia time constant 0.7, 1.0 and 1.5 MWs/MVA. At short circuit the fault duration causes larger currents and longer recovery times for both load models. At motor start the size of the transformer, in MVA, and the inertia time constant affects the motors starting time. Larger transformer means shorter time because of lesser drop in voltage. A larger inertia time constant means longer time.  If only the size of the voltage drop is of interest and not the course of the event, the motors start admittance can be used instead.
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Stargård, Susanna, and Sara Hassan. "The Success Factors of PSS Development : A Transformation of Traditional Manufacturing Companies." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-19520.

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The competition and increasing customers‘ demands makes traditional manufacturing companies consider new ways of differentiate themselves. One way of doing this is to develop product service system (PSS) solutions. PSS solutions are a total offering, where the customer purchases the use of a solution instead of a physical product. This bachelor thesis within the School of Innovation Design and Engineering at Mälardalen University aims to determine the success factor of PSS development at ICT and AM, which are two traditional Swedish manufacturing companies. To do this, the main challenges of transforming ICT and AM into PSS providers will be identified. The thesis also aims to determine if there is a need for change of performance measurements and key performance indicators (KPIs) to enable this transformation. A theoretical review is presented to help the readers in the understanding of the thesis areas. Interviews at ICT and AM were made to get a view of the situations at the companies considering PSS development. The information gathered at the interviews stated the major challenges of transforming both companies into PSS developers. With the theoretical framework and the stated challenges, an analysis was made to determine the success factors of PSS development.The identified success factors of PSS development were Senior management clarification of strategic intent, Cultural change management, Teamwork culture, Internal communication mechanisms, External communication mechanism, Customer relationship, Motivating breakthrough ideas, Project core competency, Cross-functional collaboration, Cross-functional development, Allocation of resources, Training and education, Knowledge management, Customer satisfaction data, Risk management, Product positioning, Portfolio of product opportunities, Product functional content, Knowledge of market potential, Product service processes, Product environment, Development process, Responsibilities of team members, Concurrent development, Internal task coordination, Organizational readiness for sales, Internal marketing and External marketing.Based on the theoretical framework and interviews a statement was made; it is crucial to change the performance measurement and KPIs if implementing PSS, to support collaboration between departments and contribute to the overall success for the companies.
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Hively, Myiah Hutchens. "The effects of self-efficacy statements in anti-tobacco fear appeal PSAs." Online access for everyone, 2006. http://www.dissertations.wsu.edu/Thesis/Spring2006/m%5Fhively%5F042706.pdf.

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29

Nguyen, Minh-Triet [Verfasser]. "PSCA als DNA-Vakzine zur Behandlung des duktalen Pankreaskarzinoms / Minh Triet Nguyen." Bonn : Universitäts- und Landesbibliothek Bonn, 2012. http://d-nb.info/104351094X/34.

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30

Zhang, Jerry Jiaer. "PSS : a phonetic search system for short text documents." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/5537.

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Finding the right information from the increasing amount of data on the Internet is not easy. This is why most people use search engines because they make searching less difficult with a a variety of techniques. In this thesis, we address one of them called phonetic matching. The idea is to look for documents in a document set based on not only the spellings but their pronunciations as well. It is useful when a query contains spelling mistakes or a correctly spelled one does not return enough results. In these cases, phonetic matching can fix or tune up the original query by replacing some or all query words with the new ones that are phonetically similar, and hopefully achieve more hits. We propose the design of such a search system for short text documents. It allows for single- and multiple-word queries to be matched to sound-like words or phrases contained in a document set and sort the results in terms of their relevance to the original queries. Our design differs from many existing systems in that, instead of relying heavily on a set of extensive prior user query logs, our system makes search decisions mostly based on a relatively small dictionary consisting of organized metadata. Our goal is to make it suitable for start-up document sets to have the comparable phonetic search ability as those of bigger databases, without having to wait till enough historical user queries are accumulated.
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LI, XIN, and YUNLEI ZHANG. "New Business Potential while Embedding PSS Concept to Wanxiang." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-11707.

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Tam, Pui-ching Celine, and 譚佩貞. "Resident participation in management of HOS/PSPS courts: problems encountered and possible solutions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31968466.

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Tam, Pui-ching Celine. "Resident participation in management of HOS/PSPS courts : problems encountered and possible solutions /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21029076.

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34

Radhakrishnan, Aravind. "Android Phone Controlled Beagle Board Based PSCR in a Dynamic Spectrum Access Environment." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/35046.

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Public Safety Cognitive Radio (PSCR) is a Software Defined Radio(SDR) developed by the Center for Wireless Telecommunications (CWT) at Virginia Tech. PSCR can configure itself to interoperate with any public safety waveform it finds during the scan procedure. It also offers users the capability to scan/classify both analog and digital waveforms. The current PSCR architecture can only run on a general purpose processor and hence is not deployable to the public safety personnel. In the first part of this thesis an Android based control application for the PSCR on a Beagle Board(BB) and the GUI for the control application are developed. The Beagle Board is a low-cost, fan- less single board computer that unleashes laptop-like performance and expandability. The Android based Nexus One connected to the Beagle Board via USB is used to control the Beagle Board and enable operations like scan, classify, talk, gateway etc. In addition to the features that exist in the current PSCR a new feature that enables interoperation with P25 (CPFSK modulation) protocol based radios is added. In this effort of porting the PSCR to Beagle Board my contributions are the following (i) communication protocol between the Beagle Board and the Nexus One (ii) PSCR control application on the Android based Nexus One (iii) detection/classification of P25 protocol based radios. In the second part of this thesis, a prototype testbed of a Dynamic Spectrum Access (DSA) broker that uses the Beagle Board PSCR based sensor/classifier is developed. DSA in simple terms is a concept that lets the user without license (secondary user) to a particular frequency access that frequency, when the licensed user (primary user) is not using it. In the proposed testbed we have two Beagle Board based sen- sor/classifiers that cooperatively scan the spectrum and report the results to the central DSA broker. The DSA broker then identifies the frequency spectrum with- out primary users and informs the secondary users about the free spectrum. The secondary users can then communicate among each other using the frequency band allocated by the DSA broker. When the primary user enters the spectrum occupied by the secondary user, the DSA broker instructs the secondary user to use a different spectrum. Based on the experiments conducted on the testbed setup in the CWT lab environment, the average time taken by the DSA broker to detect the presence of primary user is 0.636 secs and the average time taken for the secondary user to leave the frequency band that interferes with the primary user is 0.653 secs.
Master of Science
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Söderhielm, Kristofer. "Integration av konstruktionsdatabas och styrsystem." Thesis, Linköpings universitet, Institutionen för systemteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-80805.

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The Mission at ÅF Industry in Norrkoping was about optimizing bulk data handling while importing process tag types from their construction database into the Process Controlled System of type Siemens PCS7.I found three different methods to solve the task. Two of them were using different software from Siemens under the premise that the report from the database was corrected as needed. The third variant was manually creating the circuits. All methods worked out fine but there were times when one was better than another.To solve this task I had access to all software presented in chapter 2 “Programvara” (=Software). I also had a close cooperative with employers at ÅF that works with the system today and also with personal att Siemens AG in Germany and Sweden.
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Zhang, Pei. "Co-ordination and control of power system damping controllers to enhance small signal stability." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321949.

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Hrag, Margossian. "VALIDATION OF THE PSS/E MODEL FOR THE GOTLAND NETWORKR." Thesis, KTH, Elektriska energisystem, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119577.

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The aim of the project is to revise the load flow and dynamic PSS/E models of the Gotland network and validate them against a set of measurements collected during a major disturbance, a three phase short circuit in the 70 kV system. The main task in revising the model is to convert the induction machine models of the wind turbines into user and manufacturer wind turbine models. The validation of the model is divided into two phases. The first is to use the measurements as well as some assumptions on the wind power generation and load distribution from the time of the fault to validate the dynamic behaviour of the system. The second is to use new measurements during a normal operation day. The latter would not be very helpful to illustrate the dynamic behaviour of the system, because of the lack of a major fault that would drastically affect the system, but it would nevertheless be useful to validate the load flow with greater accuracy.
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Martins, Eduardo B. G. "Lymphocyte subsets and immune mechanisms in primary sclerosing cholangitis (PSC)." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294347.

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Akis, B. Ceylan. "Preparation of Pd-Ag/PSS composite membranes for hydrogen separation." Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0430104-113019.

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Yao, Xiao. "Grayscale patterning of PEDOT: PSS films by multi-photon lithography." Thesis, Kansas State University, 2008. http://hdl.handle.net/2097/780.

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Master of Science
Department of Chemistry
Daniel A. Higgins
Lithography techniques have been widely used to fabricate optical, electronic and optoelectronic devices with sub-micron scale spatial resolution. In the most common lithographic procedures, a light sensitive polymer, called a photoresist, is exposed and developed to form a binary relief pattern on a substrate. The finest features are produced by X-ray or electron-beam methods, both of which are very expensive to employ. Less expensive methods use ultraviolet (UV) light to expose the photoresist through a photomask. The resolution in these methods is somewhat lower and is governed by diffraction of light by the photomask, the quality of the photomask, and by any chemical/physical development steps subsequently employed. Due to the above limitations, we have been investigating direct-write, ablative multiphoton lithography as an alternative method for preparing high-resolution patterns. With this method, near-IR light from an ultrafast pulsed laser source is focused into a polymer film, leading to depolymerization and vaporization of the polymer. Arbitrary binary patterns can be produced by raster scanning the sample while controlling exposure of the film to the laser. Importantly, high-resolution etching of the polymer film is achieved without the use of a photomask and without chemical development steps. While arbitrary patters are easily prepared, it is also possible to prepare three-dimensional (i.e. grayscale) surface relief structures. In this study, ablative multiphoton photolithography is used to prepare binary and grayscale structures in thin films of PEDOT:PSS, an electrically conductive organic polymer blend. A simple kinetic model is proposed to explain the etching process. Data on the power-dependence of polymer etching can be fit to this model and is used to determine the order of the nonlinear optical process involved. The etch depth as a function of laser focus is also investigated and shown to follow the same kinetic model. The results show that three-dimensional (grayscale) patterns can be prepared by modulating either the laser power or the laser focus. Images of several binary and grayscale structures prepared by this method are presented.
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Thornström, Axel. "Strömbegränsare i synkrongeneratorer : En studie av strömbegränsarmodeller i PSS/E." Thesis, Uppsala universitet, Elektricitetslära, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-282507.

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It is well known that a crucial factor determining the transmission capacity with regards to the voltage stability limit of a stressed power system, is the limitation of field and stator current of overexcited generators. These limiters are commonly referred to as overexcitation limiters (OEL) and stator current limiters (SCL). This thesis investigates the representation of overexcitation limiters and stator current limiters in the Swedish power system and how they could be implemented in the power system simulator PSS/E. Dynamic simulations in PSS/E are performed to investigate and validate differences between model types and parameters. The thesis compares different types of limiters and presents a representative set of parameters based on the documentation and implements them into PSS/E. The result from the study is a recommendation to migrate to limiter model MAXEX2 for generators without stator current limiters. The MAXEX2 model uses an inverse time characteristic which is becoming more common in installed voltage regulators. This feature makes it possible for extended use of generators before limiter action is applied. The MAXEX2 model is also possible to tune into a fixed time delay to represent older types of limiters.
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Ranc, Anne-Gaëlle. "Phenol Soluble Modulins et lipopolysaccharide de Legionella pneumophila : rôle dans la réponse immunitaire innée." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1010/document.

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Legionella pneumophila (Lp) est une bactérie ubiquitaire dans les environnements aqueux et responsable d’une pneumopathie potentiellement sévère : la légionellose. La majorité des souches impliquées appartiennent au sérogroupe 1 (Lp1) et à un sous- groupe spécifique de souches portant un épitope particulier dites mAb3/1+. Cependant, la différence de distribution entre les souches retrouvées dans l’environnement et celles impliquées en clinique n’est pas clairement élucidée. Notre travail a porté sur la détection de deux facteurs de virulence de Lp. Nous avons voulu mettre en évidence l’existence de Phenols Soluble Modulines (PSMs), peptides uniquement décrit chez Staphylocoques et avons ainsi pu démontrer l’activité de peptides prédits par analyse in silico chez Lp capables d’activer la réponse inflammatoire par la voie du NF-?B et sont dotés d’une action cytotoxique. Notre deuxième axe d’étude a porté sur le lipopolysaccharide (LPS) de Lp. Afin de vérifier si la prédominance de certaines souches était liée à un biais diagnostique, nous avons voulu tout d’abord vérifier la sensibilité de 3 tests urinaires diagnostiques envers le LPS extrait de souches de différents sous- groupes de Lp1 et sérogroupes de Lp et avons ainsi pu montrer que ces tests sont capables de détecter tous les LPS de Lp1. La sensibilité envers le LPS des autres sérogroupes est très variable mais reste insuffisante pour permettre leur détection. Nous avons ensuite utilisé ces LPS extraits pour vérifier la réponse immunitaire innée en fonction des souches de Lp1. Ainsi les souches mAb3/1+ activent moins le système immunitaire que les souches mAb3/1-, ce qui pourrait expliquer alors une moins bonne clairance de ces souches permettant leur multiplication à l’origine d’une infection. Au final, notre travail a permis d’étudier deux facteurs de virulence potentiels au sein de Lp, pouvant expliquer partiellement la prédominance de certaines souches en pathologie humaine
Legionella pneumophila (Lp) is a ubiquitous intracellular bacterium found widely in the environment and is the cause of an opportunistic infection named legionellosis. The majority of the strains involved belong to serogroup 1 (Lp1) and to a specific subgroup named mAb3/1+, linked to a specific epitope expressed at the cell membrane. However the distribution difference between the strains found in the environment and the ones involved in pathology is not fully understood. We here studied two virulence factors of Lp. We first demonstrated the existence of Phenols Soluble Modulines (PSMs), smalls peptides that only have been described for Staphylococcus and found that the peptides that were predicted for Lp by in silico analysis were able to activate the innate immune response by NF-?B pathway and were able to have a cytotoxic activity. We also studied the lipopolysaccharide (LPS) of Lp. To found out if the predominance of some strains was linked to a diagnosis biais, we first evaluated the sensitivity of 3 urinary antigens tests against extracted LPS of strains belonging to all the sous-groups of Lp1 and serogroups of Lp. We then demonstrated that those tests are able to detect all LPS of Lp1, independently of mAb3/1 character. The sensitivities of the 3 tests were very variable for the other serogroups of Lp, but were too low to be able to detect those LPS in practice. We then used these extracted LPS to evaluate the innate immune response for different strains of Lp1. We demonstrated that mAb3/1- strains needed lower dose of LPS to activate the innate immune response than mAb3/1+ strains, which could be linked to a better clearance of the bacteria from the host, which doesn’t develop an infection. This work has studied two potentially virulent factors of Lp, which could partially explain the predominance of some strains of Lp in human pathology
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Asker, Helene, and Maria Backström. "En psykometrisk utvärdering av frågeformulären PSAS-C och APSQ som mått på sömnrelaterad oro." Thesis, Örebro University, School of Law, Psychology and Social Work, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-9604.

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Vårt syfte med denna studie var att göra en psykometrisk utvärdering av frågeformulären PSAS-C (Pre sleep arousal scale) och APSQ (Anxiety and preoccupation about sleep questionnaire). Teoretiska modeller har kommit fram till att kognitiv uppvarvning och förvrängd subjektiv perception av sömn skapar oro som kan bidra till utveckling av insomni. För att fånga upp oro vid insomni används idag två frågeformulär, PSAS-C och APSQ. Deltagare från en svensk longitudinell studie (n = 2333) ombads att svara på de två formulären. Båda skalorna visade på en god begreppsvaliditet och intern samstämmighet. Faktoranalyser, korrelationer och jämförelser av medelvärden visar att båda frågeformulären har goda psykometriska egenskaper och kan vara till stor nytta som mätinstrument för att fånga upp oro vid insomni.

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Bird, Stefan Charles, and stbird@seatiger org. "Adaptive Techniques for Enhancing the Robustness and Performance of Speciated PSOs in Multimodal Environments." RMIT University. Computer Science and IT, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20081027.122244.

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This thesis proposes several new techniques to improve the performance of speciated particle swarms in multimodal environments. We investigate how these algorithms can become more robust and adaptive, easier to use and able to solve a wider variety of optimisation problems. We then develop a technique that uses regression to vastly improve an algorithm's convergence speed without requiring extra evaluations. Speciation techniques play an important role in particle swarms. They allow an algorithm to locate multiple optima, providing the user with a choice of solutions. Speciation also provides diversity preservation, which can be critical for dynamic optimisation. By increasing diversity and tracking multiple peaks simultaneously, speciated algorithms are better able to handle the changes inherent in dynamic environments. Speciation algorithms often require a user to specify a parameter that controls how species form. This is a major drawback since the knowledge may not be available a priori. If the parameter is incorrectly set, the algorithm's performance is likely to be highly degraded. We propose using a time-based measure to control the speciation, allowing the algorithm to define species far more adaptively, using the population's characteristics and behaviour to control membership. Two new techniques presented in this thesis, ANPSO and ESPSO, use time-based convergence measures to define species. These methods are shown to be robust while still providing highly competitive performance. Both algorithms effectively optimised all of our test functions without requiring any tuning. Speciated algorithms are ideally suited to optimising dynamic environments, however the complexity of these environments makes them far more difficult to design algorithms for. To increase an algorithm's performance it is necessary to determine in what ways it should be improved. While all performance metrics allow optimisation techniques to be compared, they cannot show how to improve an algorithm. Until now this has been done largely by trial and error. This is extremely inefficient, in the same way it is inefficient trying to improve a program's speed without profiling it first. This thesis proposes a new metric that exclusively measures convergence speed. We show that an algorithm can be profiled by correlating the performance as measured by multiple metrics. By combining these two techniques, we can obtain far better insight into how best to improve an algorithm. Using this information, we then propose a local convergence enhancement that greatly increases performance by actively estimating the location of an optimum. The enhancement uses regression to fit a surface to the peak, guiding the search by estimating the peak's true location. By incorporating this technique, the algorithm is able to use the information contained within the fitness landscape far more effectively. We show that by combining the regression with an existing speciated algorithm, we are able to vastly improve the algorithm's performance. This technique will greatly enhance the utility of PSO on problems where fitness evaluations are expensive, or that require fast reaction to change.
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45

Mensah, Kwaku Sarpong. "Improving Stability of Ghana's Power System Using Power System Stabiliser(PSS)." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elkraftteknikk, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-12884.

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Stability of a power system is vital for its reliable operation and maintaining system stability has been a big challenge for engineers over the years. One way of improving system stability is the use of power system stabiliser (PSS). Its main function is to add damping to the generator rotor oscillation by modulating the generator excitation so as to develop a component of electrical torque in phase with the rotor speed deviation. In Ghana, two power stations have their generators equipped with PSS but none of the PSS are activated. The main objective of this study is to assess how the stability of the power system of Ghana can be improved by activating the power system stabilizers (PSS) on the excitation system of some of the generating units. To effectively perform the study the following questions had to be answered.To what extent will the activation of the PSS on some generating units affect the overall system dynamic performance?Where in the power system should the PSS be activated?To what extend can the PSS reduces system oscillation? What improvement can be made to the power system to optimise the performance of the PSS?Data of Ghana and the interconnected systems were first collected, reviewed and all the systems were modelled using PSSE program. Steady state stability studies were then performed to identify the inadequacy in the system during steady state operations. Five base cases including peak and average load condition with and without contingency were used for this study. Dynamic stability studies were also carried out by selecting appropriate dynamic models for generators, exciters and governors that best fit the dynamic behaviour of the generating units in the PSSE program. Appropriate PSS models were selected for units equipped with PSS based on manufacturers’ recommendation. Series of dynamic simulations were carried out to identify the best location and parameter settings for the PSS. Small signal stability studies were also carried out to complement the results obtained from the transient studies using NEVA. There was however a defect in the NEVA program and full results could not be obtained.In conclusion, Ghana’s system is likely to experience voltage collapse during a transmission outage on some critical lines at peak period unless some loads are shed. This risk can be reduced by improving the power factor to 0.95 using more reactive power compensating devices (capacitor bank) at the local substation. Transient stability results also show that the best location for the PSS to effectively damped oscillation is Akosombo GS. Inter-area oscillations of 0.5Hz between Ghana and Ivory Coast systems, local-area oscillation of 0.8Hz between the Akosombo units and Aboadze units in Ghana, were effectively damped within 7sec with PSS at Akosombo GS. It is highly recommended that PSS at Akosombo generation station be activated since their application has a positive impact on the dynamic performance of Ghana’s system. Steady state stability be improved by correcting the power factor at the local stations and line relay settings reviewed to accommodate the present operating condition. It is also recommended that the PSS be coordinated effectively with the protection and control devices for optimal performanc
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46

Karl, Ralph. "PSS Center for Independent Living evaluation of the residential service program /." Online version, 2008. http://www.uwstout.edu/lib/thesis/2008/2008karlr.pdf.

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47

Flores, Jonas Gomes. "Fatores relacionados à determinação do sexo de potros da raça PSC." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/179251.

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As biotécnicas da reprodução na espécie equina avançaram na última década e os criadores de equinos começaram a questionar as possibilidades de interferência na determinação do sexo dos potros. A determinação do sexo é importante, pois o sexo do potro possui grande influência no valor comercial do mesmo. O objetivo do presente estudo foi avaliar a influência do momento da cobertura em relação ao momento da ovulação no sexo dos potros e outros fatores como: idade da égua e garanhão; indutor da ovulação; ovário em que ocorreu a ovulação e o diâmetro do folículo pré-ovulatório também foram avaliados. O estudo foi realizado em Haras na região de Bagé e Aceguá (RS) – Brasil (31°24'06.1''S 54°07'47.5''W) e (31°30'16.0''S 54°07'45.5''W) nas estações de monta de 2011 a 2015. Utilizou-se 259 ciclos reprodutivos de 160 éguas e 22 garanhões da raça Puro Sangue de Corrida. Informações como agente indutor de ovulação utilizado (Deslorelina; n = 187 ou hCG; n = 72); data da cobertura (n = 259); momento da ovulação em relação a cobertura (+ 24 horas; n = 69 e - 24 horas; n = 190); idade da égua (G1: até 8 anos; n = 123, G2: 9 até 14 anos n = 110 e G3: >14 anos; n = 26); idade do garanhão (Até 14 anos; n = 11 e >15 anos; n = 11) ; ovário em que a ovulação ocorreu (Direito; n = 122 e Esquerdo; n = 137); foram registrados e avaliados No total de potros nascidos, 136 foram machos (52,51%) e 123 foram fêmeas (47,49%). O tempo decorrido após a cobertura não influenciou o sexo dos produtos, nas éguas que ovularam com – 24h após a indução da ovulação: 104 potros (54,74%) eram machos e 86 (45,26%) eram fêmeas, enquanto que nas éguas que ovularam com + 24h, 32 potros (46,38%) eram machos e 37 (53,62%) eram fêmeas. A porcentagem de fêmeas nascidas em relação a idade da égua foi de 46,34% (n=57), 47,27% (n=52) e 46,15% (n=12) nos grupos G1, G2 e G3 respectivamente. Garanhões com idade até 15 anos tiveram 44,14% (n=49) de fêmeas e com mais de 15 anos 49,66% (n=73) eram fêmeas. Não houve diferença no sexo dos produtos quanto ao agente indutor da ovulação (Deslorelina x hCG) e ovário em que ocorreu a ovulação. O presente estudo concluiu que nenhum dos fatores estudados alterou a proporção macho:fêmea dos potros nascidos.
The biotechnologies of reproduction in equine species have been improved in the last decade and the horse breeders started to inquire about the possibility of intervention regarding to the sex determination in foals. Sex determination is important because the sex of the foal has a great influence on the commercial value of the foal. The aim of the present study is was to evaluate the influence of the time of the breeding in relation to time of ovulation in the sex of the foals, besides analyzing other factors such as: the age of the mare and the stallion; ovulation inductor, ovary and the diameter of the preovulatory follicle. The study was accomplished in studs located Bagé/RS and Aceguá/RS – Brazil (31°24'06.1''S 54°07'47.5''W) and (31°30'16.0''S 54°07'45.5''W) during the breeding seasons from 2011 to 2015, using 259 reproductive cycles of 160 mares and 22 stallions of Thoroughbred breed. Information like the induction of ovulation agent that was used (Deslorelin; n = 187 or hCG; n = 72); date of breeding (n = 259); time of ovulation in relation to the breeding (+24 hours; n = 69 and -24 hours; n = 190); age of the mare (G1: up to the age of 8; n = 123 G2: from the age of 9 to the age of 14; n = 110 and G3: >14 years old; n = 26); age of the stallion (up to the age of 14; n = 11 and >15 years old; n = 11); ovary in which the ovulation occurred (Right; n = 122 and Left; n = 137) were catalogued and evaluated As result, 136 (52,51%) were born colts and 123 (47,49%) were born fillies. The elapsed time from breeding to ovulation did not influence on the sex of the product, on mares that ovulated in less than 24 hours after the ovulation induction: 104 foals (54,74%) were male and 86 (45,26%) were female, whereas in the mares that ovulated in more than 24 hours, 32 foals (46,38%) were male and 37 (53,62%) were female. The percentage of born females regarding to the age of the mare was 46,34% (n = 57), 47,27% (n = 52) and 46,15% (n = 12) in the groups G1, G2 and G3, respectively. From stallions up to the age of 15 years, 44,14% (n = 49) were females and from those which were older than 15 years old, 49,66% (n = 73) were females. There was no difference regarding the sex of the product in relation to the ovulation inducer agent (Deslorelin x hCG) and ovary in which the ovulation occurred. None of the factors studied modified the male:female proportion of the born foals.
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48

Zhu, Yichao. "Modelling the transition from channel-veins to PSBs in the early stage of fatigue tests." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:ad163287-19cc-4318-995a-378df1d80260.

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Dislocation channel-veins and persistent slip bands (PSBs) are characteristic dislocation configurations that are of interest to both industry and academia. However, existing mathematical models are not adequate to describe the mechanism of the transition between these two states. In this thesis, a series of models are proposed to give a quantitative description to such a transition. The full problem has been considered from two angles. Firstly, the general motion and instabilities of arbitrary curved dislocations have been studied both analytically and numerically. Then the law of motion and local expansions are used to track the shapes of screw segments moving through channels, which are believed to induce dislocation multiplication by cross-slip. The second approach has been to investigate the collective behavior of a large number of dislocations, both geometrically necessary and otherwise. The traditional method of multiple scales does not apply well to describe the pile-up of two arrays of dislocations of opposite signs on a pair of neighbouring glide planes in two dimensional space. Certain quantities have to be more accurately defined under the multiple-scale coordinates to capture the much more localised resultant stress caused by these dislocation pairs. Through detailed calculations, one-dimensional dipoles can be homogenised to obtain some insightful results both on a local scale where the dipole pattern is the key diagnostic and on a macroscopic scale on which density variations are of most interest. Equilibria of dislocation dipoles in a two-dimensional regular lattice have been also studied. Some natural transitions between different patterns can be found as a result of geometrical instabilities.
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49

Khuong, Thi thu huong. "Investigation of the regulation of photosynthesis at the molecular level for improvement of plant growth and productivity under limiting light conditions." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4001.

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La lumière est indispensable à la survie des plantes via le processus photosynthétique, pourtant les plantes doivent s'adapter à différentes conditions environnementales où la quantité et la qualité de la lumière peuvent être non optimales pour la photosynthèse. Cela peut provoquer des dégâts photo-induits par formation d'espèces réactives de l'oxygène (ROS), qui sont dangereux pour la plante. Pour limiter la formation des ROS, les plantes mettent en place une régulation importante qui est la dissipation thermique de l'énergie absorbée en excès, appelé Non photochemical quenching (NPQ). Il est connu que la protéine PsbS joue le rôle clé de senseur du pH bas du lumen thylacoïdal, qui est le signal initial pour activer le NPQ. Dans le contexte de cette thèse, on propose d'étudier l'hypothèse que l'absence de la protéine PsbS (diminué NPQ) pourrait augmenter la croissance et la productivité des plantes en conditions contrôlées de faible lumière par l'éminilation de la protéine PsbS chez Arabidopsis thaliana et chez la tomate. Les résultats obtenus indiquent qu'en lumière faible les plantes mutantes montrent une augmentation du rendement de photosystème II conduisant une croissance et un nombre de fleurs significativement augmentés par rapport aux plantes sauvages.De plus, une autre régulation de la photosynthèse, nommée « transitions d'état », est importante pour optimiser la photosynthèse en réponse aux variations de la quantité et de la qualité de la lumière, grâce à la migration réversible des antennes collectrices d'énergie LHCII phosphorylées du PSII au PSI, c'est aussi étudié dans ma thèse
Light is indispensable for plant survival, but plants have to cope with different environmental situations where light quantity and quality can be not optimal for photosynthesis. This can cause photodamage due to the formation of harmful reactive oxygen species (ROS). To limit ROS formation, plants developed a mechanism important as the dissipation of excess absorbed energy as heat and is called Non Photochemical Quenching (NPQ). The PsbS protein plays the key role of sensor of the low lumenal pH, the signal to activate NPQ. In this thesis, we proposed and investigated the hypothesis that PsbS absence (NPQ decrease) would improve growth under controlled low light upon elimination of the PsbS in Arabidopsis and tomato plants. Results showed that the increase of photosystem II yield in mutant plants leaded to a significant improvement of growth and flower number in mutants as compared with wild type plants under low light, suggesting that this mutation could be useful to improve plant performances in controlled conditions where light is strongly limiting. In addition, another photosynthetic regulation, called “state transitions”, which is important to optimize photosynthesis under variable light for intensity and quality thank to reversible migration of phosphorylated light harvesting complexes LHCII from PSII to PSI also investigated in my thesis
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50

Barquet, Ana Paula Bezerra. "Creation of product-service systems (PSS) proposals in the fuzzy front-end." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18156/tde-04052015-101933/.

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Product-service systems (PSS), defined as a system of products, services, infrastructure, and networks that aims to satisfy customer needs, support business innovation and has the potential to lead to improved environmental performance. The adoption of PSS requires modifications in the business model of companies or even the creation of new ones. The decision to modify or create business models occurs in the fuzzy front-end through the development of proposals. In this sense, the creation of PSS proposals might assist the adoption of PSS business models in enterprises. However, companies still need support to adopt PSS business models due to three main reasons. First, most of the studies about PSS business models mention its importance but do not explore which content should compose such models. Second, PSS business models are explored considering a partial view of business model dimensions. Finally, there is a lack of methods and tools that support the adoption of PSS business models in the fuzzy front-end. Thereby, the aim of this study is to develop a method, named Configurator of PSS Proposals, to cope with these challenges and assist the creation of PSS proposals for current or new business models. By means of systematic literature review, consulting with experts and an explorative case study, the method was developed. It is composed by eight steps and each step addresses a business model dimension, e.g. value proposition. The steps encompass a range of tasks that must be performed in order to create a PSS proposal. To support carrying out the tasks, a help element is available. This help contains additional information to support the utilization of the method, such as: examples of companies that adopted PSS and hints of practices, methods and tools. To evaluate the method, it was applied through a case study in the context of a research project. The aim was to create a PSS proposal for a bicycle concept and verify whether the method reach its purpose, i.e. is able to support the creation of a PSS proposal. Final considerations include contributions and limitations of this study. An example of contribution of the method is provision of a shared knowledge about PSS between different areas of expertise. As limitation, the lack of application of the method in a real case is highlighted. Additionally, future research is addressed based mainly on the insights gathered in the second case study, e.g. the inclusion of new tasks and relations between them.
Sistema produto-serviço (SPS), definido como um sistema de produtos e serviços, infraestrutura e networks e que visa aumentar a satisfação de clientes, auxilia na inovação nos negócios e tem o potencial de levar à melhoria de desempenho ambiental. A adoção de SPS requer a criação ou modificação dos modelos de negócios das empresas. A decisão de criar ou modificar um modelo de negócio ocorre no fuzzy front-end por meio da criação de propostas. Desta forma, acredita-se que criação de propostas para SPS auxilia na adoção de modelos de negócio para SPS. No entanto, empresas requerem auxilio na adoção de modelos de negócio para PSS devido a três principais motivos. Primeiro, a maioria dos estudos sobre modelos de negócio para SPS mencionam sua importância, porém não exploram o conteúdo que deve compor esses modelos. Segundo, pesquisas sobre modelos de negócio para SPS levam em consideração uma visão parcial das dimensões de modelos de negócio. Finalmente, é constatada a carência de métodos e ferramentas que auxiliem na adoção de modelos de negócio para PSS no fuzzy front-end. O objetivo desse trabalho é desenvolver um método, denominado Configurador de Propostas de SPS, que guie empresas na criação de propostas de SPS para negócios novos e existentes. Por meio de revisão sistemática de literatura, consulta com especialistas e um estudo de caso exploratório, o método foi desenvolvido. Ele é composto por oito passos e cada passo aborda uma dimensão do modelo de negócios, como por exemplo, proposição de valor. Ainda, cada passo engloba várias tarefas que devem ser executadas para que a proposta de SPS seja criada. Como suporte para realizar as tarefas, um elemento ajuda foi criado. Este elemento inclui exemplos de empresas que adotaram SPS e dicas de práticas, métodos e ferramentas. Com objetivo de avaliar o método, uma aplicação no contexto de um projeto de pesquisa foi realizada, por meio de um estudo de caso. O objetivo dessa aplicação foi criar uma proposta de SPS para um conceito de uma bicicleta e verificar se o método alcança seu propósito, que é ajudar na criação de propostas de SPS. Considerações finais incluem contribuições e limitações do estudo. Um exemplo de contribuição do método é o fornecimento de um conhecimento compartilhado sobre PSS entre diferentes áreas de conhecimento. A falta de aplicação do método em um caso real é uma das limitações deste trabalho. Adicionalmente, pesquisas futuras são sugeridas, como por exemplo, a inclusão de novas tarefas no método e novas relações entre elas, conforme sugerido pelos participantes do segundo estudo de caso.
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