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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Frequency control ancillary services in large interconnected systems

Diouf, Edmond January 2013 (has links)
This research focuses on frequency control ancillary services in large interconnected systems. It analyses and assesses possible alternatives for optimal and innovative solutions of major frequency control issues in large interconnected systems within liberalised electricity markets. Possible improvements in the performance of frequency control are identified. A framework of frequency control ancillary services in large interconnected systems by including loads and wind generation is also proposed.The research has been motivated by the paucity of research in power system dynamics focusing on large interconnected systems such as the European synchronous system and the Eastern interconnection which experience important frequency control challenges. These challenges include:- Decline in frequency response in the Eastern interconnection - Deterministic frequency deviations observed at the top of the hours in the European synchronous systemFrequency control issues became critical when electricity markets were deregulated and frequency control became an ancillary service with a decidedly commercial focus. This commercial focus has spawned a lot of work on frequency control markets and economics whereas not much research has been devoted to dynamic simulation of large interconnected systems. Apart from this commercial focus, frequency control in large interconnected systems is still based on historical practices mainly because changes suggested in the literature can be barely applied in large interconnected systems. This is essentially because dynamic simulation studies are uncorrelated with frequency control markets and economics. More specifically, dynamic studies do not take into account the characteristics of each reserve activated and also the way the reserve is activated. With the deregulation of the electricity market, reserve is considered as a product and not necessarily a response provided by a unit. The main objectives of this research therefore are to solve critical frequency control issues in large interconnected deregulated electricity systems, which may present potential economic benefits. To achieve these objectives, frequency control in large interconnected systems is studied by considering on one hand frequency control theory and on the other hand its implementation in practice taking account of frequency control ancillary service markets as well as the economics and practical consequences of frequency control. This approach is necessary to accommodate the future evolution of frequency control in large interconnected systems. The proposed approach is illustrated through a model of frequency control in the European synchronous system, where practices are better known, are clearly standardised and also where frequency data has been obtained.
42

Recherche sur l'activité accessoire dans les contrats de commande publique / Research on the ancillary activity in public order contracts

Valette, Benjamin 11 December 2014 (has links)
Fréquemment, en marge des contrats de commande publique, leur titulaire développe une activité accessoire grâce aux moyens mis à leur disposition dans le cadre de ces contrats. L'objet de cette recherche est de scruter les questions juridiques soulevées par cette pratique, qui a d'abord un objectif financier. Il s'agit, pour certains opérateurs, d'utiliser les contrats leur confiant une activité principale pour développer une activité accessoire à celle-ci et ce, dans le but de générer des recettes supplémentaires.Longtemps cette activité accessoire est apparue comme un phénomène marginal, d'où sa large ignorance par la doctrine qui ne lui a jusqu'ici consacré aucune étude spécifique. Au contraire, la recherche a révélé, dans l'activité accessoire, une situation fréquente et de grande ampleur. / Often, ancillary to public order contracts, the beneficiary of such public order contracts develops an ancillary activity thanks to the means made available to them as part of these contracts. The purpose of this research is to analyse the legal questions raised by this practice, the aim of which is first and foremost financial. For certain operators, the aim is to use the contracts granting them a principal activity in order to develop an ancillary activity which will generate additional revenues.This ancillary activity was for a long time an exceptional phenomenon, hence the widespread ignorance by the doctrine which until now had not devoted any specific study to the subject. The research has revealed, on the contrary, that the ancillary activity is in fact frequent and widespread.
43

Desenvolvimento de catalisadores de rutênio coordenados a toluilfosfinas para polimerização via metátese / Development of ruthenium catalysts coordinated with tolylphosphines for metathesis polymerization

Marcella de Sousa Ferreira 20 February 2014 (has links)
Este trabalho investigou a influência das propriedades estéricas e eletrônicas de ligantes ancilares em complexos do tipo [RuCl2(PR3)3] e [RuCl2(PR3)xLy], onde R = p-toluil e L = piperidina, N-butilamina e isonicotinamida, em reações de polimerização via metátese por abertura de anel (ROMP) e de copolimerização via metátese por abertura de anel (ROMCP) de norborneno (NBE) e norbornadieno (NBD). O objetivo foi observar como o efeito estéreo (dado em função do ângulo de cone, &theta;) e eletrônico (dado em função de pKa) da PpTol3 pode influenciar a reatividade em ROMP e ROMCP quando está sozinha ou combinada com amina. <br /> O complexo [RuCl2(PpTol3)3] (1) produziu rendimentos melhores que 70% por 10 min a 23 &deg;C, com Mw na ordem de 104 g.mol-1 e IPD de 2,2. O melhor rendimento obtido quando o complexo [RuCl2(PpTol3)2(pip)] (2) é utilizado foi observado nas reações por 30 min a 50 &deg;C (80,2%) com Mw de 1,5 x 105 g.mol-1. IPD de 2,0 foi obtido com 2 por 60 min a 23 &deg;C. O complexo 2 demonstrou ser mais reativo que o complexo 1 nas reações de ROMP de NBD, com rendimento de 60,1% por 60 min a 50 &deg;C. O impedimento estéreo de PpTol3 em 1, provavelmente é o responsável pelo melhor desempenho com NBE, com um período de indução mais curto para iniciar a ROMP. Por outro lado, o sinergismo amina&rarr;Ru&rarr;olefina deve contribuir para a ativação de NBD com 2. <br /> Os rendimentos para poliNBE com os complexos contendo N-butilamina e isonicotinamida foram de 68 e 35%, respectivamente, por 60 min a 50 &deg;C, isso mostra que a atividade catalítica para estes complexos sobrepõe o baixo ângulo de cone da Nbutilamina e a capacidade de retrodoação da isonicotinamida. Os rendimentos para o poliNBD foram de 30,9 e 9,1, respectivamente. <br /> As reações de copolimerizações com NBE e NBD (ROMCP) foram realizadas com uma quantidade fixa de NBE ([NBE]/[Ru] = 5000) e diferentes concentrações de NBD ([NBD]/[Ru] = 1000, 2000 ou 3000), por 60 min a 50&deg;C. Para ambos os complexos 1 e 2, os rendimentos foram acima de 80% quando aumentou-se a [NBD] e os materiais poliméricos apresentaram microestruturas lisas. Os valores de Tg (acima de 60 &deg;C) obtidos quando o complexo 1 foi utilizado, sugerem a presença de NBD nas cadeias poliméricas. Com o complexo 2, os valores de Tg foram entre 33 e 37 &deg;C, indicando a possibilidade de polimerização apenas do NBE. / This study investigated the influence of steric and electronic properties of ancillary ligands in complexes of the type [RuCl2(PR3)3] and [RuCl2(PR3)xLy], with R = p-tolyl and L = piperidine, N-butylamine and isonicotinamide, for ring-opening metathesis polymerization (ROMP) and ring-opening metathesis copolymerization of norbornene (NBE) and norbornadiene (NBD). The aim was to observe how the steric (in terms of the cone angle, &theta;) and electronic (in terms of pKa) effects of PpTol3 can tune the reactivity in ROMP and ROMCP when alone or combining with an amine. <br /> The [RuCl2(PpTol3)3] complex (1) produced yields better than 70% for 10 min at 23 &deg;C, with Mw in the order of 104 g.mol-1 and PDI of 2,2. The best yields obtained when the complex [RuCl2(PpTol3)2(pip)] (2) was used was observed in the reactions 30 min at 50 &deg;C (80%), with Mw of 1.5 x 105 g.mol-1. PDI of 2.0 was obtained with 2 for 60 min at 23 &deg;C. The complex 2 proved to be more reactive than complex 1 for ROMP of NBD, with yield of 60.1% for 60 min at 50 &deg;C. The steric hindrance of PpTol3 in 1 probable provided the difference in the reactive for NBE, with a short induction period to initiate the ROMP. However, the amine&rarr;Ru&rarr;olefin synergism in 2 probable contributed to the better activation of NBD. <br /> The yields for polyNBE with the N-butylamine and isonicotinamide derivative complexes were 68 and 35%, respectively, for 60 min at 50 &deg;C., it shows that the catalytic activity of these complexes to overlap the low cone angle of the N-butylamine and the ability of the backdonation of the isonicotinamide. Proceeds to poliNBD were 30.9 and 9.1, respectively. <br /> Copolymerizations with NBE and NBD (ROMCP) were performed with a fixed quantity of NBE ([NBE]/[Ru] = 5000) and different concentrations of NBD ([NBD]/[Ru] = 1000, 2000 or 3000), for 60 min at 50 &deg; C. The yields were better than 80% when increasing the [NBD] and the polymeric materials showed smooth microstructures. The obtained Tg values (60 &deg;C) obtained when the complex 1 was used, indicated the presence of NBD in the polymer chains. With the complex 2, the Tg values were in the range of 33 - 37 &deg;C, indicating the possibility of polymerization of only NBE.
44

Doprovodné služby podniku / Customer Services in the Company

Záškodová, Lenka January 2014 (has links)
This diploma thesis deals with the evaluation of current situation of the company IP IZOLACE POLNÁ, s.r.o. in its competitive environment. The aim of my thehis was to propose new ancillary services for the company based on the analyzes. According to the findings proposal consists of activities that should enhance its competitiveness in the coming years.
45

Nekonkurenční doložky v soutěžním právu Evropské unie a vybraných členských států. / Non-compete clauses in the competition law of the European Union and selected member states.

Klímová, Eva January 2021 (has links)
Non - compete clauses in the competition law of the European union and selected member states This diploma thesis is focused on the use and regulation of non-compete clauses in the competition law of the European Union, the Czech Republic and Great Britain. The aim of this thesis is to analyse the applicable regulation and decision-making practice of the relevant authorities concerning the non-compete clauses in the selected jurisdictions, draw a comparison between them and, at the end of each chapter, make an evaluation to what extent does the relevant practice differ on the level of European law, the law of the Czech Republic or Great Britain. The thesis is mainly dedicated to the use of non-compete clauses in lease and acquisition agreements. The first chapter is focused on the theoretical introduction to the matter, containing a short summary of the fundamental regulation and soft law of the competition authorities. The second chapter is centred around the analysis of decisions concerning the non-compete clauses in lease agreements. The individual decisions are examined and compared at the end of the second chapter. The comparison is made by using the division of the anti-competitive agreements to the categories of "object-type agreements" and "effect-type agreements". The third chapter is concentrates...
46

Maximizing the Value of Large-Scale Solar PV Parks through Battery Storage and Ancillary Services : An analysis using multiple-integer linear programming optimization

Ekström, Nora January 2023 (has links)
Renewable power production is becoming a necessity to improve society and overcome the challenges of climate change. In Sweden, large-scale solar PV power is growing year-on-year and today comprises 1 percent of electricity production. Solar power, however, is an intermittent form of electricity production which, whilst being renewable, contributes to increasing grid instability. For the grid to stay in balance, at grid frequency 50 Hz, electricity must be consumed at the time of production. If there is a surplus of production or a sudden decrease in consumption, the frequency will deviate from the nominal value. When introducing larger quantities of intermittent power production, the power system inertia decreases, and the frequency becomes prone to deviate. To combat this, the Swedish TSO Svenska Kraftnät procures ancillary services which aid the grid when needed. For solar PV power to be able to contribute to these marketplaces, a battery storage solution system (BESS) is utilized. This thesis aimed to investigate the economic feasibility of co-locating a solar photovoltaic (PV) park with a battery energy storage system (BESS) and to determine the optimal size of the BESS. The study utilized a linear optimization model to simulate the operation of a 14 MW solar PV park with different sizes of BESS ranging from 1 MWh to 14 MWh. The analysis considered the revenue generated by providing different services to the electricity grid, such as energy arbitrage and frequency regulation. The results indicate that co-locating a solar PV park with a BESS increases revenue, and the optimal BESS size for a 14 MW solar PV park is between 1 and 8 MWh. Above this range, the revenue recedes due to the limitations of the grid connection, which restricts the BESS from participating in the ancillary service markets. The analysis considers the running costs associated with power discharge to the grid and initial BESS investment. The study did not account for ancillary market bids that are not accepted, which could have a significant impact on the revenue generated. The ongoing trend of lowering battery prices could further boost the economic assessment and increase interest in all battery sizes, resulting in larger battery system installations in general.
47

Friction Stir Welding for Armor Applications

Lyda, Paul John, II January 2022 (has links)
No description available.
48

Affärsmodeller mot digitalisering : Förändringar av värdeskapande strategier och tjänstefokus

Dyrke, Sofia, Karlsson, Alexander January 2023 (has links)
The technical use to create value and ease the work for companies have through the last years taken major steps. The use of information technology (IT) has revolutionized opportunities and forced companies to change their offerings in order not to lose their competitiveness in the market. Today, an established company no longer solely consists of a product that represents its business idea, but primarily how to create value together with the market's customers to meet their needs. The digital solution has thus become a popular way for companies to not only streamline the market but also their own business model. Through major changes in society, companies are forced to follow the development, which has brought about a customer focus. IT- companies use a huge business model with groups within the company with cutting-edge expertise to provide solutions to meet the customer's needs. Companies thus start from a basic offer of standardized services, but through co-creation with customers, the company's business model is further developed. The study therefore intends to understand how companies' business models are affected by digitization and how companies can make strategic and operational adaptations in order to meet the challenges of the future. This will be carried out with the support of interviews of the IT-companies` managers as well as the responsible group managers focused on digital tools and their business models. The results produced for the study show tendencies that the companies' business models contain certain more prominent elements in order to maintain a strong whole. These components need to somehow permeate the company's groups consisting of various cutting-edge competencies. Companies have also had different opinions regarding sustainability thinking and how they work around this in different ways. As the business market today consists of great competitiveness, the trust companies build with their customers is essential. A lost customer can create strong contacts with other companies throughout their entire customer lifetime and thus become difficult to win over at a later stage. Digitization will thus have a strong influence on the companies' business models for a continued strong strategy.
49

Implications of Pleiotropy for Clinical Genetic Testing: Assessing the Patient Perspective

Butson, Melissa B. 22 May 2012 (has links)
No description available.
50

An Exploration of the Global Clinical Trial Ancillary Supply Chain and the Drivers of Success During the Pre, In, and Post Phases

Santomauro, Joanne DeFusco January 2019 (has links)
Until recently, academic and practitioner research on clinical trial supply chains focused on identifying innovative models and solutions in providing comparator and study drugs to global clinical sites. Due to the expansion of outsourcing efforts by pharmaceutical organizations, newly enacted global laws and regulations, and the continued push to increase the speed at which new drugs gain market approval, a new and extremely complex global “ancillary” supply chain has emerged. This manuscript focuses on the clinical trial ancillary supply chain: a supply chain that develops the end-to-end process resulting in the distribution and quality management of medical products and devices, consumable supplies, and patient giveaways to global clinical trial sites. Based on a series of quantitative analyses, this research assesses the influence of the customer, country, and product on the overall success of the supply chain. Three factors emerged from these analyses as having a direct influence on the clinical trial ancillary supply chain; product characteristics, magnitude (components of size), and stability (components of changes in scope). Part II of this research sought to understand the success of the supply chain by evaluating the moderating effects of knowledge management, organizational culture, therapeutic area, and type of shipment. Assessments of 444 customer and server surveys yielded components of a sense of shared culture, shared communication and transparency, and feeling educated and supported. Quantitative data analysis supported that these components had a moderating influence on success during the pre-trial phase of the supply chain. These research findings provide insight into the internal and external drivers of success within the complex and emergent clinical trial supply chain – a supply chain that helps pharmaceutical organizations bring innovative therapies to market and most important, those patients in need of such therapies to improve or even save their lives. / Business Administration/Interdisciplinary

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