903 resultados para Field of power


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The Laboratory of Intelligent Machine researches and develops energy-efficient power transmissions and automation for mobile construction machines and industrial processes. The laboratory's particular areas of expertise include mechatronic machine design using virtual technologies and simulators and demanding industrial robotics. The laboratory has collaborated extensively with industrial actors and it has participated in significant international research projects, particularly in the field of robotics. For years, dSPACE tools were the lonely hardware which was used in the lab to develop different control algorithms in real-time. dSPACE's hardware systems are in widespread use in the automotive industry and are also employed in drives, aerospace, and industrial automation. But new competitors are developing new sophisticated systems and their features convinced the laboratory to test new products. One of these competitors is National Instrument (NI). In order to get to know the specifications and capabilities of NI tools, an agreement was made to test a NI evolutionary system. This system is used to control a 1-D hydraulic slider. The objective of this research project is to develop a control scheme for the teleoperation of a hydraulically driven manipulator, and to implement a control algorithm between human and machine interaction, and machine and task environment interaction both on NI and dSPACE systems simultaneously and to compare the results.

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Työn tavoitteena on kehittää ABB:lle palvelutuote, jota voidaan tarjota voimalaitosasiakkaille. Uuden palvelutuotteen tulee vastata ABB:n uuden strategian linjauksiin. Palvelulla tarjotaan asiakkaille 1.1.2015 voimaan tulleen energiatehokkuuslain määrittelemien pakollisten toimenpiteiden suoritusta. Työssä kerätään, käsitellään ja analysoidaan tietoa voimalaitosasiakkaille suunnatun palvelun tuotteistamisprosessin päätöksenteon tueksi. Palvelutuotteen kehittämistä varten tutkitaan ABB:n nykyisiä palvelutuotteita, osaamista ja referenssi projekteja, energiatehokkuuslakia, voimalaitosten energiatehokkuus-potentiaalia ja erilaisia energiakatselmusmalleja. Päätöksenteon tueksi tehdään referenssiprojektina energia-analyysi voimalaitokselle, jossa voimalaitoksesta tehdään ipsePRO simulointiohjelmalla mallinnus. Mallinnuksen ja koeajojen avulla tutkitaan voimalaitoksen minimikuorman optimointia. Markkinatutkimuksessa selvitetään lainsäädännön vaikutusta, nykyistä markkinatilannetta, potentiaalisia asiakkaita, kilpailijoita ja ABB:n mahdollisuuksia toimia alalla SWOT–analyysin avulla. Tutkimuksen tulosten perusteella tehdään päätös tuotteistaa voimalaitoksille palvelutuote, joka sisältää kaikki toimet energiatehokkuuslain asettamien vaatimusten täyttämiseen yrityksen energiakatselmuksen vastuuhenkilön, energiakatselmuksen ja kohdekatselmuksien teon osalta. Lisäksi työn aikana Energiavirasto myönsi ABB:lle pätevyyden toimia yrityksen energiakatselmuksen vastuuhenkilönä, mikä on edellytyksenä palvelun tarjoamiselle.

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At present, one of the main concerns of green network is to minimize the power consumption of network infrastructure. Surveys show that, the highest amount of power is consumed by the network devices during its runtime. However to control this power consumption it is important to know which factors has highest impact on this matter. This paper is focused on the measurement and modeling the power consumption of an Ethernet switch during its runtime considering various types of input parameters with all possible combinations. For the experiment, three input parameters are chosen. They are bandwidth, link load and number of connections. The output to be measured is the power consumption of the Ethernet switch. Due to the uncertain power consuming pattern of the Ethernet switch a fully-comprehensive experimental evaluation would require an unfeasible and cumbersome experimental phase. Because of that, design of experiment (DoE) method has been applied to obtain adequate information on the effects of each input parameters on the power consumption. The whole work consists of three parts. In the first part a test bed is planned with input parameters and the power consumption of the switch is measured. The second part is about generating a mathematical model with the help of design of experiment tools. This model can be used for measuring precise power consumption in different scenario and also pinpoint the parameters with higher influence in power consumption. And in the last part, the mathematical model is evaluated by comparing with the experimental values.

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Electric energy demand has been growing constantly as the global population increases. To avoid electric energy shortage, renewable energy sources and energy conservation are emphasized all over the world. The role of power electronics in energy saving and development of renewable energy systems is significant. Power electronics is applied in wind, solar, fuel cell, and micro turbine energy systems for the energy conversion and control. The use of power electronics introduces an energy saving potential in such applications as motors, lighting, home appliances, and consumer electronics. Despite the advantages of power converters, their penetration into the market requires that they have a set of characteristics such as high reliability and power density, cost effectiveness, and low weight, which are dictated by the emerging applications. In association with the increasing requirements, the design of the power converter is becoming more complicated, and thus, a multidisciplinary approach to the modelling of the converter is required. In this doctoral dissertation, methods and models are developed for the design of a multilevel power converter and the analysis of the related electromagnetic, thermal, and reliability issues. The focus is on the design of the main circuit. The electromagnetic model of the laminated busbar system and the IGBT modules is established with the aim of minimizing the stray inductance of the commutation loops that degrade the converter power capability. The circular busbar system is proposed to achieve equal current sharing among parallel-connected devices and implemented in the non-destructive test set-up. In addition to the electromagnetic model, a thermal model of the laminated busbar system is developed based on a lumped parameter thermal model. The temperature and temperature-dependent power losses of the busbars are estimated by the proposed algorithm. The Joule losses produced by non-sinusoidal currents flowing through the busbars in the converter are estimated taking into account the skin and proximity effects, which have a strong influence on the AC resistance of the busbars. The lifetime estimation algorithm was implemented to investigate the influence of the cooling solution on the reliability of the IGBT modules. As efficient cooling solutions have a low thermal inertia, they cause excessive temperature cycling of the IGBTs. Thus, a reliability analysis is required when selecting the cooling solutions for a particular application. The control of the cooling solution based on the use of a heat flux sensor is proposed to reduce the amplitude of the temperature cycles. The developed methods and models are verified experimentally by a laboratory prototype.

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Point-of-care (POC) –diagnostics is a field with rapidly growing market share. As these applications become more widely used, there is an increasing pressure to improve their performance to match the one of a central laboratory tests. Lanthanide luminescence has been widely utilized in diagnostics because of the numerous advantages gained by the utilization of time-resolved or anti-Stokes detection. So far the use of lanthanide labels in POC has been scarce due to limitations set by the instrumentation required for their detection and the shortcomings, e.g. low brightness, of these labels. Along with the advances in the research of lanthanide luminescence, and in the field of semiconductors, these materials are becoming a feasible alternative for the signal generation also in the future POC assays. The aim of this thesis was to explore ways of utilizing time-resolved detection or anti-Stokes detection in POC applications. The long-lived fluorescence for the time-resolved measurement can be produced with lanthanide chelates. The ultraviolet (UV) excitation required by these chelates is cumbersome to produce with POC compatible fluorescence readers. In this thesis the use of a novel light-harvesting ligand was studied. This molecule can be used to excite Eu(III)-ions at wavelengths extending up to visible part of the spectrum. An enhancement solution based on this ligand showed a good performance in a proof-of-concept -bioaffinity assay and produced a bright signal upon 365 nm excitation thanks to the high molar absorptivity of the chelate. These features are crucial when developing miniaturized readers for the time-resolved detection of fluorescence. Upconverting phosphors (UCPs) were studied as an internal light source in glucose-sensing dry chemistry test strips and ways of utilizing their various emission wavelengths and near-infrared excitation were explored. The use of nanosized NaYF :Yb3+,Tm3+-particles enabled the replacement of an external UV-light source with a NIR-laser and gave an additional degree of freedom in the optical setup of the detector instrument. The new method enabled a blood glucose measurement with results comparable to a current standard method of measuring reflectance. Microsized visible emitting UCPs were used in a similar manner, but with a broad absorbing indicator compound filtering the excitation and emission wavelengths of the UCP. This approach resulted in a novel way of benefitting from the non-linear relationship between the excitation power and emission intensity of the UCPs, and enabled the amplification of the signal response from the indicator dye.

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Industrial, electrical power generation, and transportation systems, to name but a few, rely heavily on power electronics to control and convert electrical power. Each of these systems, when encountering an unexpected failure, can cause significant financial losses, or even an emergency. A condition monitoring system would help to alleviate these concerns, but for the time being, there is no generally accepted and widely adopted method for power electronics. Acoustic emission is used as a failure precursor in many applications, but it has not been studied in power electronics so far. In this doctoral dissertation, observations of acoustic emission in power semiconductor components are presented. The acoustic emissions are caused by the switching operation and failure of power transistors. Three types of acoustic emission are observed. Furthermore, aspects related to the measurement and detection of acoustic phenomena are discussed. These include sensor performance and mechanical construction of experimental setups. The results presented in this dissertation are the outset of a research program where it will be determined whether an acoustic-emission-based condition monitoring method can be developed.

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Over the recent years, smart grids have received great public attention. Many proposed functionalities rely on power electronics, which play a key role in the smart grid, together with the communication network. However, “smartness” is not the driver that alone motivates the research towards distribution networks based on power electronics; the network vulnerability to natural hazards has resulted in tightening requirements for the supply security, set both by electricity end-users and authorities. Because of the favorable price development and advancements in the field, direct current (DC) distribution has become an attractive alternative for distribution networks. In this doctoral dissertation, power electronic converters for a low-voltage DC (LVDC) distribution system are investigated. These include the rectifier located at the beginning of the LVDC network and the customer-end inverter (CEI) on the customer premises. Rectifier topologies are introduced, and according to the LVDC system requirements, topologies are chosen for the analysis. Similarly, suitable CEI topologies are addressed and selected for study. Application of power electronics into electricity distribution poses some new challenges. Because the electricity end-user is supplied with the CEI, it is responsible for the end-user voltage quality, but it also has to be able to supply adequate current in all operating conditions, including a short-circuit, to ensure the electrical safety. Supplying short-circuit current with power electronics requires additional measures, and therefore, the short-circuit behavior is described and methods to overcome the high-current supply to the fault are proposed. Power electronic converters also produce common-mode (CM) and radio-frequency (RF) electromagnetic interferences (EMI), which are not present in AC distribution. Hence, their magnitudes are investigated. To enable comprehensive research on the LVDC distribution field, a research site was built into a public low-voltage distribution network. The implementation was a joint task by the LVDC research team of Lappeenranta University of Technology and a power company Suur-Savon S¨ahk¨o Oy. Now, the measurements could be conducted in an actual environment. This is important especially for the EMI studies. The main results of the work concern the short-circuit operation of the CEI and the EMI issues. The applicability of the power electronic converters to electricity distribution is demonstrated, and suggestions for future research are proposed.

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The credibility of the rules and the elements of power constitute fundamental keys in the analysis of the political institutions. This paper opens the "black box" of the European Union institutions and analyses the problem of credibility in the commitment of the Stability and Growth pact (SGP). This Pact (SGP) constituted a formal rule that tried to enforce budgetary discipline on the European States. Compliance with this contract could be ensured by the existence of "third party enforcement" or by the coincidence of the ex-ante and ex-post interests of the States (reputational capital). The fact is that states such as France or Germany failed to comply with the ruling and managed to avoid the application of sanctions. This article studies the transactions and the hierarchy of power that exists in the European institutions, and analyses the institutional framework included in the new European Constitution.

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A new approach to the determination of the thermal parameters of high-power batteries is introduced here. Application of local heat flux measurement with a gradient heat flux sensor (GHFS) allows determination of the cell thermal parameters in di_erent surface points of the cell. The suggested methodology is not cell destructive as it does not require deep discharge of the cell or application of any charge/discharge cycles during measurements of the thermal parameters of the cell. The complete procedure is demonstrated on a high-power Li-ion pouch cell, and it is verified on a sample with well-known thermal parameters. A comparison of the experimental results with conventional thermal characterization methods shows an acceptably low error. The dependence of the cell thermal parameters on state of charge (SoC) and measurement points on the surface was studied by the proposed measurement approach.

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The thesis interprets the caveat of Article 194(2) TFEU in order to assess the use of the Article as a legal basis for energy provisions provided by the European Union. The research subject is the Energy Title in the Treaty of the Functioning of the European Union and the possibilities of the application of the legal basis provided therein. The purpose is analysis of the possibilities for providing of provisions within the scope of the caveat found in Article 194(2) TFEU with special regard to the possibilities of providing renewable energy legislation. The purpose of the thesis is on one hand to provide an overview of the premises for providing of energy provisions in the EU, and on the other hand to analyse the Treaty text in order to determine the legal basis for energy provisions. The ultimate objective is to determine the correct legal basis for renewable energy provisions, aimed at the mitigation of climate change. According to Article 194(2) TFEU, the practice of the shared legislative powers in the field of energy are restricted by the retention of certain energy matters within the power of the Member States. The wording of the caveat containing the restrictions is open to interpretation and has been a subject of extensive discussion. Many scholars have argued that the caveat in Article 194(2) TFEU might obstruct decision-making in energy matters. This argument is contested, and the factual impact of the codification of the energy competences is analysed. The correct legal basis for energy provisions depends on the final interpretation of the text of the caveat and the level of significance of the effect of the measure. The use of Article 194(2) TFEU as a legal basis might not be the only option. There is a possibility that the legal bases within the Environmental Title might be used as legal bases for energy provisions in addition to Article 194(2) TFEU.

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The thesis interprets the caveat of Article 194(2) TFEU in order to assess the use of the Article as a legal basis for energy provisions provided by the European Union. The research subject is the Energy Title in the Treaty of the Functioning of the European Union and the possibilities of the application of the legal basis provided therein. The purpose is analysis of the possibilities for providing of provisions within the scope of the caveat found in Article 194(2) TFEU with special regard to the possibilities of providing renewable energy legislation. The purpose of the thesis is on one hand to provide an overview of the premises for providing of energy provisions in the EU, and on the other hand to analyse the Treaty text in order to determine the legal basis for energy provisions. The ultimate objective is to determine the correct legal basis for renewable energy provisions, aimed at the mitigation of climate change. According to Article 194(2) TFEU, the practice of the shared legislative powers in the field of energy are restricted by the retention of certain energy matters within the power of the Member States. The wording of the caveat containing the restrictions is open to interpretation and has been a subject of extensive discussion. Many scholars have argued that the caveat in Article 194(2) TFEU might obstruct decision-making in energy matters. This argument is contested, and the factual impact of the codification of the energy competences is analysed. The correct legal basis for energy provisions depends on the final interpretation of the text of the caveat and the level of significance of the effect of the measure. The use of Article 194(2) TFEU as a legal basis might not be the only option. There is a possibility that the legal bases within the Environmental Title might be used as legal bases for energy provisions in addition to Article 194(2) TFEU.

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ABSTRACT Canada is an aging society. The number of people aged sixty-five and over is rising, while the number of people under twenty is declining. These two concurrent changes in the age structure have produced a sh~ft in the demographic composition of Canada which is commonly referred to as the aging phenomenon. Regardless of whether or not the number of people under twenty continues to decline, the number of elderly in Canada will almost double over the next twenty years. This rapidly growing elderly clientele will doubtless have an impact on Canadian governments. Federal, provincial and municipal governments are presently providing a variety of programs that have a special bearing on the aged and most senior citizens are beneficiaries of one or more of these programs. The ramifications of a rapidly growing elderly clientele are obvious. In order to cope with the impact of a significant increase in the number of elderly persons, the development and implementation of aging policy must be co-ordinated at each level of government and between and among levels of government. If aging policy is not co-ordinated, the results are likely to be: inappropriate policy decisions; duplication and overlap; and, ineffective and irresponsive services. No one benefits from these results. The need for co-ordination is apparent. The purpose of this thesis is to examine existing governmental efforts to co-ordinate policy in the field of aging. These efforts are examined by focusing on interactions directed at co-ordination between and among major actors in aging policy. A framework is used to structure the description and analysis of these interactions. The variables of formalisation and intensity and the concept of power are instrumental in analysing interactions for co-ordination. The underlying intent of this thesis is to discover some of the main gaps in existing governmental efforts to co~ordinate aging policy. Gaps are, in fact, discovered. Several explanations for the existence of gaps in interactions for co-ordination are discussed. A major hypothesis involving a relationship between a bureaucratic form of organisation and interactions for coordination is suggested. Finally, three recommendations for improving co-ordination in aging policy are offered.

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This qualitative study was conducted to explore tenured faculty members’ understandings of their roles as professors. Tenure is an institutional means to enact academic freedom, which allows tenured faculty members to investigate topics of their choosing free from external influence. Academic freedom also enables faculty members to be public intellectuals who shape and critique social policies and make knowledge assertions. In effect, the faculty members are institutionally protected to speak truth to power. Purposeful sampling of 9 participants from 2 universities yielded 3 major themes: professorial identity (shaped by such factors as career stage, university culture, and faculty affiliation), professorial power (powers that participants experienced as well as the ways in which they exercised power), and professorial silencing (as a response to fiscal realities coupled with numerous governance issues). While participants were cognizant of the powers that affected their freedoms, they were less aware of the ways in which their position afforded them powers. Subtle but more potent forms of power were at play for tenured professors, but the participants saw themselves as having to work within institutional and financial constraints that limited their freedom to speak out on controversial issues. Faculty members were, thus, silenced and at times chose to self-silence. The context of the present-day university, governance models, and the financial issues affecting universities and departments worked in concert to silence this critical voice in society.

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La présence importante de plusieurs réseaux sans-fils de différentes portées a encouragée le développement d’une nouvelle génération d’équipements portables sans-fils avec plusieurs interfaces radio. Ainsi, les utilisateurs peuvent bénéficier d’une large possibilité de connectivité aux réseaux sans-fils (e.g. Wi-Fi [1], WiMAX [2], 3G [3]) disponibles autour. Cependant, la batterie d’un nœud mobile à plusieurs interfaces sera rapidement épuisée et le temps d’utilisation de l’équipement sera réduit aussi. Pour prolonger l’utilisation du mobile les standards, des réseaux sans-fils, on définie (individuellement) plusieurs états (émission, réception, sleep, idle, etc.); quand une interface radio n’est pas en mode émission/réception il est en mode sleep/idle où la consommation est très faible, comparée aux modes émission/réception. Pourtant, en cas d’équipement portable à multi-interfaces radio, l’énergie totale consommée par les interfaces en mode idle est très importante. Autrement, un équipement portable équipé de plusieurs interfaces radio augmente sa capacité de connectivité mais réduit sa longévité d’utilisation. Pour surpasser cet inconvénient on propose une plate-forme, qu'on appelle IMIP (Integrated Management of Interface Power), basée sur l’extension du standard MIH (Media Independent Handover) IEEE 802.21 [4]. IMIP permet une meilleure gestion d’énergie des interfaces radio, d’un équipement mobile à multi-radio, lorsque celles-ci entrent en mode idle. Les expérimentations que nous avons exécutées montrent que l’utilisation de IMIP permet d'économiser jusqu'a 80% de l'énergie consommée en comparaison avec les standards existants. En effet, IMIP permet de prolonger la durée d'utilisation d'équipements à plusieurs interfaces grâce à sa gestion efficace de l'énergie.

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Cette thèse analyse les négociations interculturelles des Gens du Centre (groupe amazonien multi-ethnique) avec les discours universels de droits humains et de développement mobilisés par l’État colombien. L’analyse se concentre sur le Plan de sauvegarde ethnique Witoto chapitre Leticia (ESP), qui est un des 73 plans formulés et implémentés par l’État colombien pour reconnaître les droits des peuples autochtones en danger par le déplacement forcé causé par les conflits armés internes. J’analyse l’ESP à travers la notion de friction (Tsing, 2005) qui fait référence aux caractéristiques complexes, inégalitaires et changeantes des rencontres contemporaines entre les différences des savoirs locaux et globaux. Mon analyse se base aussi sur des approches foucaldiennes et/ou subalternes de pouvoir comme la recherche anticoloniale et de la décolonisation, les perspectives critiques et contre-hégémoniques des droits humains, le post-développement, et les critiques du féminisme au développement. L’objectif de la thèse est d’analyser les savoirs (concepts de loi, de justice et de développement); les logiques de pensée (pratiques, épistémologies, rôles et espaces pour partager et produire des savoirs); et les relations de pouvoir (formes de leadership, associations, réseaux, et formes d’empowerment et disempowerment) produits et recréés par les Gens du Centre au sein des frictions avec les discours de droits humains et du développement. La thèse introduit comment la région habitée par les Gens du Centre (le Milieu Amazone transfrontalier) a été historiquement connectée aux relations inégalitaires de pouvoir qui influencent les luttes actuelles de ce groupe autochtone pour la reconnaissance de leurs droits à travers l’ESP. L’analyse se base à la fois sur une recherche documentaire et sur deux terrains ethnographiques, réalisés selon une perspective critique et autoréflexive. Ma réflexion méthodologique explore comment la position des chercheurs sur le terrain influence le savoir ethnographique et peut contribuer à la création des relations interculturelles inclusives, flexibles et connectées aux besoins des groupes locaux. La section analytique se concentre sur comment le pouvoir circule simultanément à travers des échelles nationale, régionale et locale dans l’ESP. J’y analyse comment ces formes de pouvoir produisent des sujets individuels et collectifs et s’articulent à des savoirs globaux ou locaux pour donner lieu à de nouvelles formes d’exclusion ou d’émancipation des autochtones déplacés. Les résultats de la recherche suggèrent que les Gens du Centre approchent le discours des droits humains à travers leurs savoirs autochtones sur la « loi de l’origine ». Cette loi établit leur différence culturelle comme étant à la base du processus de reconnaissance de leurs droits comme peuple déplacé. D’ailleurs, les Gens du Centre approprient les discours et les projets de développement à travers la notion d’abondance qui, comprise comme une habileté collective qui connecte la spiritualité, les valeurs culturelles, et les rôles de genre, contribue à assurer l’existence physique et culturelle des groupes autochtones. Ma thèse soutient que, même si ces savoirs et logiques de pensée autochtones sont liés à des inégalités et à formes de pouvoir local, ils peuvent contribuer à des pratiques de droits humains et de développement plurielles, égalitaires et inclusives.