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Lauzer, Shawn. "Fighting the War Within: A Look at Ontario Metis Life and the Creation of a New Standard Post-Powley." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23331.
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In Canada today there exists a new form of segregation towards the Métis people, called the Powley points. Because of it, Métis are being forced to become a different version of themselves, counter to their own personal identity, thereby creating a new standard of identity for Métis, one that not all Métis are able to meet because of historical factors. What the research shows is an over representation of Western Métis politics regarding Métis identity and the formation of it. I therefore, propose a change to the current status quo regarding how Métis are defined and how they are expected to define themselves within this system. For this thesis I rely primarily on archival research and textual analysis, such as journal articles, census data, and published material from the Métis organizations, to establish the current situation in Métis politics as well as my position regarding these issues.
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Ondreášová, Klára. "Stanovení vybraných perfluoroalkylových sloučenin v komplexních matricích." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217004.
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Diploma work focuses on the determination of selected representatives of perfluoroalkyl substances in complex matrices, particularly, in sewage sludge and feed. In case of sewage sludge, samples were extracted into methanol and three extractions techniques were compared: accelerated Soxhlet, pressurized liquid extraction and Powley method. Powley method showed sufficient efficiency, the lowest matrix effect and minimal background. Perfluorooctane sulfonate was present in all tested samples of sewage sludge (0.74–38.02 ng.g-1). Other detected compounds were perfluorodecanoic acid and perfluorooctanoic acid. Three extraction techniques were tested on feed samples (QuEChERS, fast methanol extraction and Powley method into acetonitrile). Powley method provided the cleanest extracts and showed simultaneously the highest recovery of native perfluoroalkyl substances and the lowest matrix effects. Perfluorooctane sulfonate and perfluorooctanoic acid were rarely present in samples of complete and supplemental feeds, while other perfluoroalkyl substances were found at levels below limit of quantification or they were not detected at all. Perfluorooctane sulfonate (0.100–2.768 ng.g-1), perfluoroundecanoic acid and perfluorotridecanoic acid were determined in all fish meal samples.
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Dhavale, Tushar. "Low power laser sintering of iron powder." Thesis, University of the West of England, Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.522529.
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Funk, Lyell. "Beyond the Powels: Alternative Narratives as Primary Solutions for the Powel House." Master's thesis, Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/314818.
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HistoryM.A.
Philadelphia is a city that constantly gazes back toward its eighteenth-century past. Many of its historic sites rely on legends from the era of the American founding fathers in order to attract visitors. The Powel House, an historic house museum that was once the home of Philadelphia's last colonial and first post-revolutionary mayor Samuel Powel, fits into this category. Yet for The Philadelphia Society for the Preservation of Landmarks, the consortium that manages the Powel House, there is a pressing need for an expanded audience and increased funding, and the story of the Patriot Mayor does not provide enough fuel to achieve these goals. This essay examines some of the Powel House's lesser-known narratives. It suggests that for historic house museums such as the Powel House that are bound to constricted historical eras, an exploration of the house's entire history is a route toward uncovering new strategies for audience engagement. The essay isolates three specific narratives from the early twentieth century, and contemplates how each individual story can be leveraged for Landmarks' broader goals.
Temple University--Theses
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Do, Tung Van. "Optimal operation of a hydroelectric reservoir." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26694.
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This thesis examines the influence of different degrees of serial correlation in the streamflow records on optimal operation of a hydroelectric reservoir. This thesis also investigates the practical aspects of choosing different decision variables, considering effects on ease of implementation, total benefit, and actual use for real-time operations.
Stochastic dynamic programming was used to optimize the long-term operation of a hydroelectric project with a single reservoir. Reservoir inflows were analyzed using monthly flow record for 58 years with the assumption that monthly inflows are either perfectly correlated, uncorrelated, or partially correlated. Reservoir level change and powerhouse discharge were considered as alternative decision variables for each of the three cases of inflow serial correlation. The optimization results were then examined and compared to determine the significance of the choice of decision variables and to explore the effects of inflow serial correlation on practical operating decisions which might be based on the results of the optimization.
It was found that (1) Case 2 in which inflows were assumed perfectly correlated and Case 3 with partially correlated inflows produce, respectively, highest and lowest total expected return, (2) the difference in total expected return between cases depends largely upon the physical characteristics of the system, (3) the reservoir level change decision case produces more conservative results than the discharge decision case, (4) the results from the reservoir level change decision are easier to use for realtime operation than those from the discharge decision case, (5) different results will be produced with different choice of decision variables.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
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Powell, Scott Lael. "Conifer cover increase in the Greater Yellowstone Ecosystem : rates, extent, and consequences for carbon." Diss., Montana State University, 2004. http://etd.lib.montana.edu/etd/2004/powell/PowellS1204.pdf.
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Ebune, Guilbert Ebune. "Carbon Dioxide Capture from Power Plant Flue Gas using Regenerable Activated Carbon Powder Impregnated with Potassium Carbonate." Connect to resource online, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1221227267.
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Abonadi, Earl E. K. "Weinberger-Powell and transformation : perceptions of American power from the fall of Saigon to the fall of Baghdad /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Jun%5FAbonadi.pdf.
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Powell, Allison L. "Database selection in distributed information retrieval a study of multi-collection information retrieval /." Full text, Acrobat Reader required, 2001. http://viva.lib.virginia.edu/etd/diss/SEAS/ComputerScience/2001/Powell/etd.pdf.
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Powell, Brian Keith. "Rawls on stability, democracy, and justice." Full text, Acrobat Reader required, 2002. http://viva.lib.virginia.edu/etd/masters/ArtsSci/Philosophy/2002/Powell/thesis.pdf.
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Madungandaba, Pam Mana. "Microstructure and mechanical properties as a function of process parameters for Ti6Al4V produced by high power laser powder bed fusion." Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/79274.
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Laser-powder bed fusion (L-PBF) processing finds its application in various metal forming industries
such as aerospace, automotive and medical industries. Ti6Al4V alloy is widely used in aerospace
applications. The main interest of studies on additive manufacturing of Ti6Al4V is to investigate the
material properties (strength, toughness and corrosion resistance) with regards to applications in the
aerospace industry. The L-PBF process allows great flexibility with regards to process control and
process design, and therefore control over microstructure and properties.
The aim of the project was to study the effect of process parameters (laser power, scanning speed, hatch
spacing, spot size and energy density) on Ti6Al4V microstructure and hardness of samples produced
by L-PBF processing. The main objective was to analyse, and statistically predict part properties based
on selected process parameters in order to enhance process understanding. The equipment that was used
to manufacture the samples is a prototype powder bed fusion setup, with an Ytterbium laser system
housed in a LENS (laser engineering net shaping) chamber. Experiments were carried out using a laser
power of 1 to 3 kW, 2 to 4 m/s scanning speed, 0.10 to 0.24 mm hatch spacing, 250 to 450 μm spot
size, and laser energy density of 33 to 200 J/mm3.
Porosity analysis was conducted using the OHAUS Explore® balance precision weighing equipment.
Optical microscope (OM) and EBSD analysis scanning electron microscope (SEM) was used to analyse
microstructures of the samples.
Porosity was found to be a function of laser power, scanning speed, hatch spacing and energy density.
Linear regression relationships were developed to predict porosity of Ti6Al4V under the set of
parameters used in the study. The lowest level of fraction porosity obtained from the built parts was
0.6% (2 kW laser power, 2 m/s scanning speed, 0.24 μm hatch spacing and 450 μm spot size). The
amount of porosity varied with laser power. A higher laser power resulted in increased micro round
porosity.
A microstructure of acicular martensite within columnar prior grains was obtained for all energy
density values used. Changes in process parameters used in the project scope were found to have a
significant effect on the microstructure and not so much on the hardness range. However, through
electron backscatter diffraction analysis a change in β content of (0.2 to 5.5%) was found with
increasing energy densities, whilst content decreased with increasing energy densities. The hardness
was between 326 and 418 HV (300 g).Dissertation (MSc)--University of Pretoria, 2019.
Metallurgy
MSc
Unrestricted
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Stone, Michael H., William A. Sands, G. G. Sands, K. C. Pierce, and Michael W. Ramsey. "Power and Power Potentiation among Strength Power Athletes." Digital Commons @ East Tennessee State University, 2007. https://dc.etsu.edu/etsu-works/4502.
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Olsen, Mary W. "Powdery Mildew." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2011. http://hdl.handle.net/10150/144805.
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3 pp.Originally published: 1998
Powdery mildew, a plant disease, appears as white, powdery spots on the leaf surface of several different kinds of plants. They are specific to their hosts and one type will infect only certain plants, usually those in the same or closely related plant families. This publication discusses the symptoms, environmental conditions, disease of powdery mildew and the methods used to prevent / control this plant disease.
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Pettersson, Viktor. "Study of the effect of process parameters in laser blown powder with superalloys : Varying laser power and scanning speed, analyzing material properties." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-68698.
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Additive manufacturing (AM) is a growing process interesting many companies in many industries. Thereare multiple processes within the familty of AM, but this study focuses on laser blown powder (LBP). LBP involves a laser beam focused on the substrate with powder being blown into the laser beam. The laser beam melts both the powder and the surface of the substrate and as the laser beam moves and the melt pool solidies it leaves a bead of solid material behind. These beads are placed next to each other creating a layer which are then stacked, building the wanted geometry. As the method develops new materials are tested and this study analyses Haynes 282 powder onto Inconel 718 substrate. Multiple process parameters are involved in the LBP method and this study focuses on the impact of laser effect and scanning speed. Each value on the process parameters was inspired by previous reports with similar equipment and process. The laser effect ranges from 1600 W to 700 W, scanning speed ranges between 900 mm/min to 300 mm/min and the powder feeding rate was also varied from 4 g/min to 3 g/min. Each sample was built as a single bead and a multilayer specimen, which is ve layers and 16 beadswide at the bottom and 12 beads wide at the top. When analyzing the samples images from microscopes were mostly used for obtaining results. An image software called ImageJ allowed measurements in an image to obtain penetration depth or primary dendrite arm spacing. ImageJ also allowed measurements of porosity by turning the image binary and calculate the fraction of white and black. The results consists of numerical values and visual analysis of the bead geometry, minimum and maximum penetration, microstructure, porosity, hardness and cracks. The results show an increased bead width around 2 mm to 4 mm and decreased bead height around 0,2 mm to 0,7 mm of single beads with increased laser effect. Increased maximum penetration depth around, 200 μm to 500 μm, withincreased laser effect. More remelt between each deposited layer causing longer dendrites with increasinglaser effect. Porosity is decreased with an increased laser power, going from 0,04 % to 0,15 %. No distinct difference in hardness is observed between the samples, ranging between 255 HV to 310 HV. It is believed that aging causes the increased hardness right above the fusion zone. Cracks were found between dendrites and is believed to be caused by Laves-phases. Most results are comparable to previous similar studies, both as trends and numerical values. The statistics of the study is limited, meaning that all results should not be taken as granted but as a general guide line for more studies. The purpose and goals of the study has been met and completed.
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Stone, Michael H., William A. Sands, Kyle C. Pierce, Michael W. Ramsey, and G. Gregory Haff. "Power and Power Potentiation among Strength-Power Athletes: Preliminary Study." Digital Commons @ East Tennessee State University, 2008. https://dc.etsu.edu/etsu-works/4138.
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Purpose: To assess the effects of manipulating the loading of successive sets of midthigh clean pulls on the potentiation capabilities of 7 international-level US weightlifters (4 men, 3 women).
Methods: Isometric and dynamic peak-force characteristics were measured with a force plate at 500 Hz. Velocity during dynamic pulls was measured using 2 potentiometers that were suspended from the top of the right and left sides of the testing system and attached to both ends of the bar. Five dynamic-performance trials were used (in the following order) as the potentiation protocol: women at 60, 80, 100, 120, and 80 kg and men at 60, 140, 180, 220, and 140 kg. Trials 2 vs 5 were specifically analyzed to assess potentiation capabilities. Isometric midthigh pulls were assessed for peak force and rate of force development. Dynamic lifts were assessed for peak force (PF), peak velocity (PV), peak power (PP), and rate of force development (RFD).
Results: Although all values (PF, PV, PP, and RFD) were higher postpotentiation, the only statistically higher value was found for PV (ICCα = .95, P = .011, η2 = .69).
Conclusions: Results suggest that manipulating set-loading configuration can result in a potentiation effect when heavily loaded sets are followed by a lighter set. This potentiation effect was primarily characterized by an increase in the PV in elite weightlifters.
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Cordts, Eike [Verfasser]. "Advanced Powder Characterization Techniques for Inhalation Powder Mixtures / Eike Cordts." Kiel : Universitätsbibliothek Kiel, 2014. http://d-nb.info/1064175279/34.
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Bennett, Fiona. "Electrostatic charge phenomena in powder processes for dry powder inhalers." Thesis, University of Sunderland, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365417.
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Cihangir, Salih. "Powder pulse plating." Thesis, University of Leicester, 2018. http://hdl.handle.net/2381/40974.
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Electroplating is a common method of obtaining metallic coatings on a surface. Generally, the metal salt is introduced into solution and a direct current is applied to the material that is to be coated. In this thesis, an alternative approach is investigated, namely the metal is introduced onto the metal surface as a powder and a pulsed current is applied to firstly dissolve some of the powder and the polarity is reversed so that the metal is then deposited. This fuses the powder to itself and to the substrate. In the current study, deep eutectic solvents were used as the electrolytes and two metals were chosen; zinc and copper. Initially the dissolution and deposition of the pure metals were investigated. It was found that far from being simple dissolution and deposition processes insoluble films were formed on the electrode surface during both deposition and dissolution for zinc and during dissolution for copper. Powder pulse plating was successfully demonstrated if the current pulse characteristics were kept within a window of size and duration which avoided these insoluble films. It was found that large metallic particles could be used when the substrate was held in a horizontal orientation and small particles were best when the electrode was held vertically. For both metals it was demonstrated that super-efficient deposition could be obtained (Faradaic current efficiency in the cathodic pulse > 100%). It was also shown that composite materials could be produced by mixing inert particles with the metallic powder.
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Nishantha, Hewamarappulige Indunil. "Powder Diffraction Methods." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1222116031.
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SZANIECKI, BARBARA PECCEI. "POLITICAL POSTER: POWER AND POTENTIAL POWER." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7141@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROA iconografia de Luís XIV foi um exemplo de representação da soberania onde a separação espacial e o acabamento perfeito das figuras refletia a organização social e política que a produzia. Contudo, fora da Igreja e do Estado, desenvolveram-se ao longo da modernidade, expressões estéticas opostas à representação do poder transcendental. Ao final do reinado de Luís XIV, surgiu um discurso histórico-político que, após revelar as múltiplas nações que lutam sob o Estado, autodialetizou-se quando, ao reivindicar uma função totalizadora, o Terceiro Estado retomou, de certa maneira, a tese monárquica onde a nação residia inteiramente na pessoa do rei. Esse movimento explicaria uma certa continuidade do discurso visual do poder - dos portraits monárquicos aos republicanos - por um lado e, por outro, a multiplicidade das formas de resistência: os cartazes políticos de maio de 68 foram a expressão das diversas nações contestadoras dos poderes e saberes constituídos daquele momento, manifestando o desejo de proximidade social e de renovação política através de elementos próximos da estética carnavalesca. Na transição contemporânea de uma soberania moderna para uma soberania imperial, a crise político-estético entre transcendência e imanência perdura. Por um lado, monarquia e aristocracia imperial apresentam a unidade transcendental através de recursos estéticos semelhantes. Por outro, no terceiro nível do Império, encontramos expressões estéticas que se afastam radicalmente das representações do poder e que denominamos manifestações de potência a partir da definição sociológica, política e ontológica de multidão.
Louis XIV´s iconography was an example of sovereignty representation in which the spatial separation and the perfect finishing of figures reflected the social and political organization that produced it. However, outside the Church and the State, aesthetic expressions opposed to transcendental representation were developed all along modern times. At the end of Louis XIV´s reign arose a historical-political discourse that, after revealing the multiple nations which fought under the State, dialectized itself when the Thiers- États, in the process of claiming a totalizing function, resumed to a certain extent the monarchic thesis in which the nation dwells entirely in the person of the king. This movement would explain on the one hand, a certain continuity of the visual discourse of power - from the monarchic to the republican portraits - and, on the other hand, the multiplicity forms of resistance: the May 1968 political posters were the expression of the diverse nations, contestant of the powers and knowledge constituted at that moment, and displayed the desire of social proximity and political renewal, through elements close to the aesthetic of Carnival. In the contemporary transition from a modern sovereignty to an imperial one, a politicalaesthetic crisis between transcendentalism and immanentism subsists. On the one hand, monarchy and imperial aristocracy introduce the transcendental unity through similar aesthetic resources. On the other hand, in the Empire third level, we find aesthetic expresions which fundamentally deviate from the representations of power and which we designate display of potential power from the sociological, political and ontological definition of multitude.
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Brisenmark, Lucas, and Simon Lindström. "Image based analysis on powder spreadability in powder bed additive manufacturing." Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277895.
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Additive manufacturing is an increasingly popular industry that has gained significant traction in the last decade. Today there exists no way to predict how a powder will spread in a powder bed additive manufacturing machine or how well it will form into thin layers. This is important because major costs can be saved by using a test that predicts the spreading behaviour of powder. This ability to be spread will be given the name spreadability. To test the spreadability of powder, a machine that mimicked the pushing of the powder in powder bed additive manufacturing was used. Since there exist no metric for spreadability, the study decided to attempt to quantify the spreadability with the help of image analysis. In the image analysis the area of the powders was measured, and through a comparison of the area against a bounding geometry, a measurement for spreadability can theoretically be attained. To further validate the results and simultaneously search for possible correlations, the experimental data was compared against flowability data obtained from angle of repose and Hall flowmeter. The results showed that the method of choice worked well for measuring the area and gave data that could be used to interpret spreadability. The data also showed what seems to be a correlation with the flowability data. While no definitive conclusions could bedrawn due to a small sample size, the collected data does seem promising for future work.Additiv tillverkning är en alltmer populär industri som har fått stor uppmärksamhet under det senaste decenniet. Idag så finns det inga sätt som man kan förutse hur ett pulver kommer att bredas ut i en pulverbädds additiv tillverkningsmaskin eller hur bra den är på att bilda tunna lager. Detta är en viktig kunskap att förstå då stora kostnader kan sparas in genom att använda ett test som förutser utbredningsförmågan av pulver. Denna förmåga får namnet spridbarhet. För att kunna testa spridbarheten hos pulver, används en maskin som härmar puttandet av pulver i en pulverbädds additiv tillverkningsmaskin. Eftersom det inte finns någon metod att mäta spridbarhet med, så valde denna studie att försöka kvantifiera spridbarheten via en bildanalys. Med denna bildanalys kunde arean av pulver mätas och genom att jämföra denna mot en avgränsande geometri kan mätdata för spridbarheten teoretiskt fås fram.För att kunna validera resultatet, och samtidigt se om det finns en korrelation, jämfördes det med flytbarhetsdata från rasvinkelmätare och Hall flödesmätare. Resultaten visade att metoden klarade av att mäta arean, och gav resultat som kan användas för att tolka spridbarhet. Den data som framtogs visade också att det möjligtvis kan finnas en korrelation mellan spridbarhet och flytbarhet. Även om något klart svar inte kan ges på grund av en liten provstorlek, så verkar resultaten vara lovande för framtida arbeten.
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Rothkegel, Lisa. "The power of power : regime dynamics and the Southern African power pool." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79984.
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Thesis (MA)--Stellenbosch University, 2013.ENGLISH ABSTRACT: Electricity is the key to economic growth and numerous aspects of human development. Africa’s installed generation capacity is dire, alongside it being the biggest funding backlog the power sector. There is however hope with the projection that to date, only 7% of this power potential has been harnessed. The increased acknowledgement of the importance of electricity for states to improve along with the knowledge that the capacity is there, has driven states within Southern Africa, to engage in increased and committed cooperation with one another. Within the greater vision of regional integration of the Regional Economic Communities (RECs) in Africa, energy was one of the first formal cooperative arrangements of the Southern African Development Community (SADC), which is the region this study will be focusing on. The form of electricity cooperation adopted was that of the Southern African Power Pool (SAPP), which is geared at increasing cross-border electricity trade and ensuring secure and reliable supply to its members. The study investigates the formation of an electricity regime within Southern Africa, by using the Southern African Power Pool as a case study. In order to properly assess the development of the SAPP, regime theory will be used. An analytical framework, derived from different studies around regime theory has been constructed. This framework assists in the analysis of the formation and evolution of the SAPP, which facilitates the assessment of the type of regime which has emerged, and guides a sound analysis around the degree of the electricity regimes effectiveness. Given the process of formation and characteristics underlying the SAPP, it has been found that it falls within the category of a negotiated regime. The analytical framework provided clear guidelines in assessing the degree of effectiveness regarding the case study at hand. After an analysis of the historical and organisational functioning of the regime - it can be argued that the SAPP is a stable and effective regime, at least on paper. It however faces various challenges, which have constrained its efficient functioning. It is concluded that members of the regime are committed to the SAPP’s continued development despite the problems identified.
AFRIKAANSE OPSOMMING: Elektrisiteit is die sleutel tot ekonomiese groei en baie ander aspekte van menslike ontwikkeling. Afrika se geïnstalleerde opwekkingskapasiteit is net so nypend soos die feit dat dit die grootste befondsing agterstand in die kragvoorsiening sektor is. Daar is egter hoop met die projeksie dat, tot op datum, slegs 7% van hierdie kragpotensiaal benut word. Die toenemende erkenning van die belang van elektrisiteit vir state om vooruit te gaan, gepaard met die wete dat die kapasiteit beskikbaar is, het state binne suider Afrika gedryf om hulle tot toenemende en volgehoue samewerking met mekaar te verbind. Binne die groter visie vir streeksintegrasie van die Streek se Ekonomiese Gemeenskappe (SEG) [Regional Economic Communities (REC)] in Afrika, was energie een van die eerste formele korporatiewe akkoorde van die Suider Afrikaanse Ontwikkelings Gemeenskap (SAOG) [Southern African Development Community (SADC)], wat die streek is waarop hierdie studie sal fokus. Die vorm wat elektrisiteit samewerking aangeneem het, was die Suider Afrika Krag Poel (SAKP) [Southern African Power Pool (SAPP)], wat aangepas is om elektrisiteithandel oor grense heen te bevorder en veilige, asook betroubare lewering aan die lede te verseker. Hierdie studie ondersoek die totstandkoming van ’n elektrisiteit ‘regime’ binne suider Afrika deur die SAKP as ’n gevalle studie te gebruik. Om die ontwikkeling van die SAKP behoorlikte asesseer, sal die regime teorie gebruik word. ’n Analitiese raamwerk, wat afgelei is van verskeie studies met betrekking tot regime teorie, is dus saamgestel. Hierdie raamwerk help met die analise van die totstandkoming en evolusie van die SAKP wat die asessering van die tipe regime, wat ontstaan het, vergemaklik en dit rig ook ‘n streng analise met betrekking tot die graad van effektiwiteit van die elektrisiteit regimes. Gegewe die proses van totstankoming en die eienskappe onderliggend aan die SAKP, is daar bevind dat dit binne die kategorie van ’n onderhandelde regime val (negotiated regime). Die analitiese raamwerk het duidelike riglyne voorsien om die effektiwiteitsgraad, met betrekking tot die gevallestudie, te assesseer. Na ’n analise van die historiese en organisatoriese funksionering van die regime – kan mens aanvoer dat die SAKP, ten minste op skrif, ’n stabiele en effektiewe regime is. Dit staar egter verskeie struikelblokke in die gesig, wat die effektiewe funksionering beperk. Daar kan egter afgelei word dat die lede van die regime toegewyd is tot die volgehoue ontwikkeling van die SAKP, ten spyte van die probleme wat geïdentifiseer is.
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Liu, Ning. "Our Power over Our Power : A paradigm shift in thederegulated power market." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-235464.
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A higher share of renewable energy in power generation is one of most ambitious goals for sustainable development under the increasing pressure of climate change. On the deregulated electricity market in Sweden, the consumers are able to choose their electricity from a specific supplier and a specific energy source, which gives them the opportunity to execute their consumer power to have positive impacts on increasing energy efficiency and renewable electricity generation by stopping buying electricity produced from fossil fuels. A new paradigm is thus proposed in this paper which provides a new perspective on purchase of the product electricity. The new paradigm makes electricity a specified product for a specific customer, the electricity audited is never mixed with that not audited, because all electricity which is audited can be traced. The aim of this study is to provide a greater understanding of the new paradigm on the deregulated electricity market. By conducting a willingness to pay survey and several deep interviews, it analyzed the main factors hindering the customers’understanding of the new market dynamics in terms of active choice in ‘green’ electricity and stopping buying fossil electricity. The results and discussions show that the new paradigm could facilitate shedding light on some important implications for strategic decision making in power companies, for policy-makers as well as customers.
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Navarrete, Pablo-Romero Javier. "Power Quality for Distributed Wind Power Generation." Thesis, KTH, Elektroteknisk teori och konstruktion, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105221.
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Wind power often is a source of voltage fluctuations and possible voltage issues are raised when considering interconnecting wind turbines to an electric grid. Also, the power electronics introduced in the wind turbines might insert more fluctuations and different PQ problems. Distributed generation seems to be a good option in order to try to mitigate these problems. The first goal of the work is to create a model of a small electric grid, using MATLAB/Simulink. The models aims to simulate various DFIG wind turbines coupled to the grid in different conditions of location and wind. Then, the main objective is to analyze the PQ in the grid with this type of turbine. For this, once the simulations have been done, the results obtained have allowed calculating different indices to study PQ in the model. Afterwards, a comparison of those indices in the different conditions is made.StandUp
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Fadda, Mario. "Aspects of power domains and power locales." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=24001.
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Several equivalent approaches to power domains are presented: the naturality of this concept for denotational semantics is stressed and its modal interpretation is explained. We show how to solve equations involving power domains and apply the theory to an equation that leads to a characterization of bisimulations. Power locales are introduced, as the analogue of both power domains and power spaces. We study the monads defined by the power locales, their algebras and the points of the power locales.
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Mir, Cantarellas Antonio. "Competitive power control of distributed power plants." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/552958.
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Nowadays, the electrical energy sector is currently found in a dramatic changing paradigm, which moves towards an increasing trend in generating power at distribution levels, where electricity is typically consumed, by means of non-conventional/renewable based generation units. These new generation technologies, termed as distributed generation, not only offers a non-pollutant, cheap and efficient source of energy to cover increasing demand, but also enhance the reliability of supply to critical loads and reduce the need for additional grid reinforcements. Aside of the technical benefits provided, distributed generation will massively integrate renewable energy resources, with new type of loads and end-user actors, such as prosumers, demand responsive loads, or electric vehicles. Where these actors will actively participate in energy and auxiliary service markets, depending on their available or constrained energy needs. For this reason, the work presented in this Thesis deals with designing and implementing advanced hierarchical control solutions to renewable-based power plants with the purpose of achieving advanced grid conection performance while reaching maximum economic benefits from its optimum real-time operation. Initially, an extensive analysis on the main renewable-based power plant hierarchical control solutions currently on the shelf, is performed. This study not only covered the specific case of renewable-based power plants, but also advanced microgrid and smart grid control solutions. Once the main renewable-based power plant hierarchical solutions were analized, a novel Hierarchical Distributed Control Structure (HDCS) is proposed for increased management of renewable-based active distributed plants. This hierarchical control structure comprises all possible functional levels from the higher long-term economic scheduling layer, to the instantaneous supervisory control of the resource, emphasizing the entire operation and control functionalities needed for increasing the integration of active distributed power plants. In order to achieve real-time control capabilities in active distribution systems, the present thesis introduces a novel power sharing control strategy, based on the competitive operation of multiple active participating agents (distributed generators, demand response and energy storage systems) through the implementation of market rules. Such control capabilities are satisfied by applying a price control signal over the entire grid control architecture, being the final-end participating agent, the responsible entity in charge of deciding its own generation/demand involvement based on its marginal or affordable electricity costs. In addition, it reduces the information volume to be transmitted and processing requirements, as the higher control levels do not need to have knowledge on the detailed distribution system topology and contributing actors. In order to have a meaningful evaluation of the proposed competitive control capabilities, a wave power plant application has been selected, which constitutes a challenging scenario for the controller itself to achieve advanced real-time control capabilities in such an oscillating renewable energy resource. In order to suitably characterize the wave energy resource profile resulting from maximum energy absorption, this Thesis introduce a novel adaptive vector controller, which maximizes the energy extraction from the resource regardless of the dominant irregular wave frequency characteristics. For the specific wave power plant application considered, the competitive control does not only ensures real-time optimum resource allocation for satisfying a given production objective, but also provides optimum long term operation of the system. As a result, overall plant costs reductions can be achieved under the competitive operation, since the plant scheduled energy is satisfied by making use of the generation units with cheaper cumulative operation costsActualmente, el sector eléctrico se encuentra inmerso en un profundo proceso de restructuración, donde de cada vez más se tiende a generar energía a nivel de distribución, mediante el uso de generación no convencional/renovable. Estas nuevas tecnologías de generación, referidas como generación distribuida, no proporcionan unicamente una fuente de energía no-contaminante, barata y eficiente para cubrir el incremento de demanda, sinó que también pueden proporcionar seguridad de suministro a cargas críticas, así como reducir la necesidad de expansiones futuras de red. Además de las capacidades técnicas proporcionadas, la generación distribuida hará posible la integración masiva de sistemas de generación renovable, con nuevos tipos de cargas y usuarios finales, como prosumidores, cargas regulables, o vehiculos eléctricos, donde todos estos usuarios participaran activamente en mercados de energía y servicios auxiliares, dependiendo de sus requisitos de uso de energía. Por lo tanto, el trabajo realizado en esta tesis se centra en el diseño e implementación de soluciones jerárquicas de control avanzado en plantas de generación renovable, con el objetivo de obtener un comportamiento harmonioso de intercacción con la red, mientras la operación de la planta maximiza los beneficios derivados de su operación en tiempo real. Inicialmente, se ha llevado a cabo una revisión extensa sobre los sistemas de control jerárquico comunmente implementados en plantas de generación renovable, en microredes y en redes inteligentes. Una vez revisados los principales sistemas de control jerárquico en este tipo de aplicaciones, se propone un una novedosa estructura de control, que cubre todos los niveles de control posibles, desde el más alto nivel de gestión económica, hasta el control detallado del recurso de generación. Para lograr capacidades de control en tiempo real en sistemas activos de distribución, la presente tesis propone una nueva estrategia de control de reparto de potencia, basada en la operación competitiva de múltiples agentes participantes activos (generadores distribuidos, respuesta de demanda y sistemas de almacenamiento de energía) mediante la implementación de reglas del mercado. Dichas capacidades de control se satisfacen aplicando una señal de precio a lo largo de toda la arquitectura de control, siendo el agente de final, el ente responsable de decidir su propia participación en la generación/demanda en función de sus propios costes de electricidad marginales o asumibles. Además, reduce el volumen de información a transmitir y los requisitos de procesamiento de datos, ya que los niveles de control más altos no necesitan tener conocimiento sobre la topología del sistema de distribución detallado ni de la contribución de los actores adyacentes. Para llevar a cabo una evaluación significativa de las capacidades del controlador competitivo propuesto, se ha seleccionado una planta de generación undimotriz, como escenario más desfavorable, ya que el controlador debe asegurar un control estable de la potencia inyectada en un escenario altamente oscilante. Con el fin de caracterizar adecuadamente el perfil de recursos de energía de las olas resultante de la máxima absorción de energía, esta Tesis introduce un nuevo controlador de vector adaptativo, que maximiza la extracción de energía del recurso independientemente de las características dominantes de frecuencia de onda irregular. Para la aplicación de la planta de energía de onda específica considerada, el control competitivo no solo garantiza la asignación óptima de recursos en tiempo real para satisfacer un objetivo de producción dado, sino que también proporciona una operación óptima del sistema a largo plazo. Como resultado, se pueden lograr reducciones generales de los costos de la planta en el marco de la operación competitiva, ya que la energía programada de la planta se satisface haciendo uso de las unidad
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Suwanapingkarl, Pasist. "Power quality analysis of future power networks." Thesis, Northumbria University, 2012. http://nrl.northumbria.ac.uk/12625/.
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Eireiner, Matthias. "Power supply integrity in low power designs." Aachen Shaker, 2009. http://d-nb.info/99845642X/04.
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Pesoti, Paulo Murinelli. "Power system restorations assisted by wind power." Thesis, University of Strathclyde, 2018. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=30465.
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This thesis investigates power systems restoration procedure and the possibility of using wind power to assist restorations. Three main factors motivate this approach: the sharp growth on wind power production during recent years, the absence of wind power on restoration procedures, and recent blackouts cases which stability issues delayed the restoration procedure. Stability studies are the base of this investigation, where a series of tools are proposed and developed due to the disparate condition of a restoration procedure. The first tool is a power flow routine, where stochastic simulations address wind speed's randomness. This computational program calculates indexes of collapse for voltage stability. This computational routine also encompasses a methodology built from an energy function tool for visualizing power systems' vulnerable and robust areas. This thesis applies the tool for restoration analysis, where its validation has been published on an academic journal. This thesis also proposes a novel methodology for visualizing the robustness areas, which uses the energy function output to form a graphical representation as the system diagram's background. This thesis designs procedures and controllers for the dynamic simulation analysis. The first is the definition of a procedure used to simulate the synchronization of wind farms during restorations. This procedure aims to mitigate impacts caused by wind farms on power systems, where two loop controls achieve the desired response. Finally, one can find an initialization procedure for wind turbines, regarding restoration conditions. The robustness areas tool validation shows that one can achieve positive results on angular stability by reinforcing vulnerable areas. The guidelines proposed by the robustness areas tool test the Brazilian system operator's restoration procedure. A number of analysis and simulations assess the proposed approach efficiency. The IEEE 30 bus system, which is a benchmark for stability studies, shows the impact of wind power on restorations. Part of the Brazilian power system addresses the proposed methodology on a real case scenario. Finally, this thesis presents a list of recommendations, which intends to guide future works to include wind power on restorations and to extend the proposed approach to other power systems.
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Dancy, Abram P. (Abram Paul). "Power supplies for ultra low power applications." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10069.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.Includes bibliographical references (p. 101-103).
by Abram P. Dancy.
M.Eng.
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Sun, Yuhao. "Power optimised narrowband power-line communication systems." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648110.
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Snyder, Rebecca. "The Power of Architecture: Architecture of Power." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1397477684.
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Solhall, Axel, and Edvin Guéry. "Coordination of Wind Power and Hydro Power." Thesis, KTH, Industriell ekologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210740.
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The goal of this project was to calculate how much wind power could be balanced with hydro power in our designated area consisting of five hydro power stations, four villages which consume power, possible locations for wind power and one connection to the national grid. To achieve this a simulation model was constructed in the GAMS software with the goal of achieving the maximum profit from the hydro power plants by considering electricity prices, inflow of water, the physical construction of the power plants and the time of year. When this was achieved, restriction for the maximum transmission load on the power grid was added as well as local wind power production as to simulate the implementation of new power sources on an old system and power grid. This would result in a maximum income in SEK as well as the most wind power which could be maintained and balanced by the designated system. This project shows how to find the optimal way to use hydro power and wind power as well as how the integration between different sources of electricity production could work, which is vital for a future powered by renewable energy and will help towards lowering emissions.
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Forestiere, Giuseppe. "Ultra-low power circuits for power management." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-143812.
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Recent developments in energy harvesting techniques allowed implementation of completely autonomous biosensor nodes. However, an energy harvesting device generally demands a customized power management unit (PMU) in order to provide the adequate voltage supply for the biosensor. One of the key blocks within this PMU is a regulation DC-DC converter. In this Master Thesis, the most relevant switched-capacitor DC-DC converter topologies that are suitable for biosensors are compared. The topology that can achieve the best efficiency and has the minimum area is chosen and designed. In order to maintain the supply voltage of the biosensor constant when the input voltage and the output current vary, a traditional Pulse-Frequency-Modulation (PFM) control is employed. An ultra-low-power PFM control circuit is designed to operate in weak inversion region. The post-layout simulations show that the designed DC-DC converter can provide an output voltage of 900mV when the output current varies between 5μA and 40μA. Additionally, the post layout simulations of the entire system, which includes the DC-DC converter and PFM control, show that the selected topology can achieve 87% peak efficiency, when the control losses are included. The main advantages of the proposed topology are its smaller chip area and its high efficiency during processing ultra-low power levels.
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Morales, Ana. "Impact of decentralized power on power systems." Doctoral thesis, Universite Libre de Bruxelles, 2006. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210841.
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Wind generation is one of the most successful sources of renewable energy for the production of electrical energy. Wind power offers relatively high capacities, with generation costs that are becoming competitive with conventional energy sources. However, a major problem to its effective use as a power source is the fact that it is both intermittent and diffuse as wind speed is highly variable and site-specific. This is translated in large voltage and frequency excursions and dynamically unstable situations when fast wind power changes. Very high wind speeds will result in sudden loss of wind generator production. The requirement to ensure that sufficient spinning reserve capacity exists within the system to compensate for sudden loss of generation becomes crucial. From the utilities operators’point of view, the primary objective is the security of the system, followed by the quality of the supplied power.In order to guard the system security and quality of supply and retain acceptable levels, a maximum allowed wind power penetration (wind margin) is normally assumed by the operators. Very conservative methods are used to assess the impact of wind power and the consequences turn to under-exploitation of the wind power potential in a given region. This thesis presents the study of actual methods of wind power assessment, divided into three parts:
1. Part I: Impact on the Security of Power Systems
2. Part II: Impact on the Power Quality
3. Part III: Impact on the Dynamic Security of Power Systems
Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished
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Ülker, Muhammed Akif. "Balancing of Wind Power : Optimization of power systems which include wind power systems." Thesis, Högskolan på Gotland, Institutionen för kultur, energi och miljö, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hgo:diva-1335.
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In the future, renewable energy share, especially wind power share, in electricity generation is expected to increase. Due to nature of the wind, wind power generation pattern includes uncertainties which affects the energy prices in the electricity markets. New simulations are needed for efficient planning process for the resources in the power systems to address the uncertainties in demand, generation, legal, economical and technical limitations. In this study, the aspects of planning process for wind power generation is described and some example scenarios are implemented with the help of MATLAB software.
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Fan, Philex Ming-Yan. "Power management and power conditioning integrated circuits for near-field wireless power transfer." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/290143.
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Near-field wireless power transfer (WPT) technology facilitates the energy autonomy of heterogeneous systems, significantly augmenting complementary metal-oxide-semiconductor field-effect-transistor (CMOS) technology. In low-power wearable devices, existing power conditioning integrated circuits do not maximize the power factor (PF) for rectification and power conversion efficiency (PCE) due to multiple conversion. Additionally, there is no core power management for the entire power flow. The majority of the research focuses on active rectifiers, which reduce the turn-on voltage for rectification. Certain studies target the output voltage regulation via feedback to the transmitter or direct battery charging without power maximization. Firstly, this study investigates a high-power factor WPT front-end circuit that is namely the mono-periodic switching rectifier (MPSR) and implemented in a 0.18µm 1.8V/5V CMOS process. Integrated phase synchronizers are used to align the waveshape of a wirelessly-coupled sinusoidal voltage source in a receiving coil to the corresponding conducting current. Using this approach, the PF can be increased from roughly 0.6 to unity without requiring any wireless or wired feedback to the transmitter. The proposed MPSR can also provide AC-DC rectification, and step up and down the sinusoidal voltage source's peak amplitude using a pulse-width modulator. Measured voltage conversion ratios range between 0.73X and 2X, and the PF can be boosted up to unity. Secondly, the wireless power system-on-chip (WPower-SoC) is proposed and implemented in a 0.18µm 1.8V/3.3V CMOS process. The WPower-SoC integrating power management can provide rectification, output voltage regulation, and battery charging. Additionally, the implementation of feedforward envelope detection (FED) can reduce the variation in a wireless power link and improve load transient responses. Simulated results demonstrate that 5% of the output voltage regulation is improved when an output load changes. Moreover, the FED reduces approximately 40% of the transient response time. Overshoot and undershoot voltages are decreased by 23% and 26.5%, respectively. The measured output voltage regulates at 3.42V and can supply output power up to 342mW. A temperature sensor as part of the power management core remains active when the WPT receivers enter sleep mode to prolong the battery usage time. In the final part of this study, a nano-watt high-accuracy temperature sensing core is implemented in a 0.18µm 1.8V/3.3V CMOS process that can self-compensate the temperature shift without the need for additional compensating techniques that consume extra power.
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Granlund, Robert. "Russan Power Projection and Power Ministries : A Study in Russian Power Ministry Influence." Thesis, Försvarshögskolan, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-3975.
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Khambekar, Jayant Vijay. "Models for compaction and ejection of powder metal parts." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0430103-145150/.
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Yap, Siaw Fung. "Micromechanics and powder compaction." Thesis, University of Birmingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.489036.
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Goodwin, A. L. "Dynamics from powder diffraction." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.599515.
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This dissertation explores the extent to which dynamical information is preserved in neutron powder diffraction data. Total scattering data collected on the GEM instrument in ISIS have been used as input for the reverse Monte Carlo (RMC) method to generate large ensembles of independent atomistic configurations consistent with the data. A method of analysing these configurations for evidence of correlated atomic motion has been developed. The method is based on a similar technique originally used to analyse molecular dynamics (MD) configurations. It has been extended further in the dissertation to account for lattice symmetry, allowing unambiguous assignment of the normal modes at each wavevector. The theory has also been used to show that phonons are determined uniquely by first- and second-order displacement correlation functions alone, and should consequently be fixed by diffraction data. The impact of various restraints and constraints in the RMC method on the dynamical information stored within configurations has been systematically studied and used to develop a new constraint (the DW constraint) that helps prevent the incorporation of damaged regions into RMC configurations without affecting the form of the phonon dispersion curves obtained. The phonons-from-diffraction approach, implemented in the program PHONON, has been applied to MgO and SrTiO3. Calculated phonon dispersion curves resemble those obtained independently in spectroscopic experiments in the low-frequency region; however, the higher-frequency modes were generally not well preserved. Temperature-dependent mode softening of the R25 and Γ15 modes in SrTiO3 could be observed, and the mode displacement vectors used to characterise the atomic translations involved in the 105 K displacive phase transition.
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Olsson, Erik. "Micromechanics of Powder Compaction." Doctoral thesis, KTH, Hållfasthetslära (Avd.), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-159142.
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Compaction of powders followed by sintering is a convenient manufacturing method for products of complex shape and components of materials that are difficult to produce using conventional metallurgy. During the compaction and the handling of the unsintered compact, defects can develop which could remain in the final sintered product. Modeling is an option to predict these issues and in this thesis micromechanical modeling of the compaction and the final components is discussed. Such models provide a more physical description than a macroscopic model, and specifically, the Discrete Element Method (DEM) is utilized. An initial study of the efect of particle size distribution, performed with DEM, was presented in Paper A. The study showed that this effect is small and is thus neglected in the other DEM studies in this thesis. The study also showed that good agreement with experimental data can be obtained if friction effects is correctly accounted for. The most critical issue for accurate results in the DEM simulations is the modeling of normal contact between the powder particles. A unified treatment of this problem for particles of a strain hardening elastic-plastic material is presented in Paper B. Results concerning both the elastic-plastic loading, elastic unloading as well as the adhesive bonding between the particles is included. All results are compared with finite element simulation with good agreement with the proposed model. The modeling of industry relevant powders, namely spray dried granules is presented in Paper C. The mechanical behavior of the granules is determined using two types of micromechanical experiments, granule compression tests and nanoindentation testing. The determined material model is used in an FEM simulation of two granules in contact. The resulting force-displacement relationships are exported to a DEM analysis of the compaction of the granules which shows very good agreement with corresponding experimental data. The modeling of the tangential forces between two contacting powder particles is studied in Paper D by an extensive parametric study using the finite element method. The outcome are correlated using normalized parameters and the resulting equations provide the tangential contact force as function of the tangential displacement for different materials and friction coefficients. Finally, in Paper E, the unloading and fracture of powder compacts, made of the same granules as in Paper C, are studied both experimentally and numerically. A microscopy study showed that fracture of the powder granules might be of importance for the fracture and thus a granule fracture model is presented and implemented in the numerical model. The simulations show that incorporating the fracture of the granules is essential to obtain agreement with the experimental data.QC 20150122
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Rathbone, T. "Aerated flow of powder." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373688.
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Bazar, Natalie Lane. "Powdery mildew cost comparison /." Click here to view, 2009. http://digitalcommons.calpoly.edu/hcssp/1.
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Thesis (B.S.)--California Polytechnic State University, 2009.Project advisor: Jim Ahern. Title from PDF title page; viewed on Jan. 20, 2010. Includes bibliographical references. Also available on microfiche.
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Adams, John B. "Applying the Powell Doctrine." Quantico, VA : Marine Corps Command and Staff College, 2008. http://handle.dtic.mil/100.2/ADA491136.
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Bruno, William M. Bridges William B. "Powder core dielectric waveguides /." Diss., Pasadena, Calif. : California Institute of Technology, 1986. http://resolver.caltech.edu/CaltechETD:etd-03192008-084301.
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Joyau, Isabelle. "L'oeuvre romanesque d'Anthony Powell." Paris 4, 1992. http://www.theses.fr/1992PA040188.
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Avec ses sept romans individuels et les douze volumes de la fresque a dance to the music of time (1951-1975), anthony powell a cree une oeuvre romanesque touffue, ambigue et difficile. Cette etude a ete organisee autour des trois notions d'espace referentiel, d'espace hermeneutique et d'espace imaginaire. Espace referentiel: powell a legue, surtout dans a dance, une remarquable chronique d'une partie de la societe britannique d'une epoque, celle qui va de la premiere guerre mondiale aux annees soixante-dix. Le milieu decrit est circonscrit a la upper-class et aux cercles artistiques et litteraires. On assiste au recul de l'ordre patricien traditionnel et a la montee de couches nouvelles sur les fronts mondain, economique et politique. Espace hermeneutique, car interrogations et desir de transparence figurent au coeur de la thematique powellienne. Le caractere d'oeuvre ouverte de la fresque s'accorde au caractere aporetique de la quete de verite. Le monde powellien est un monde du signe rebelle, peuple d'etres de fuite et marque par une esthetique de l'incertitude. Une impression de malaise domine l'espace imaginaire. Vacuite existentielle et langagiere, thematique carcerale omnipresente, maux du corps et de l'esprit, conferent a l'oeuvre une tonalite thymique essentiellement dysphorique. La richesse de l'invention comique et notamment l'humour souriant de powell attenuent cependant l'impression debilitante. Ils rendent finalement supportable un regard lucide porte sur l'absurdite du mondeIn his seven individual novels and the twelve volumes of his dance to the music of time series (1951-1975), anthony powell has created subtle and complex works of fiction. This study is structured around three organizing principles: referential, hermeneutic and imaginary. Referential since powell, especially in a dance, has written a remarkable chronicle of one section of british society between the first world war and the 1970's. Powell concentrates on a portrayal of the upper class as well as on artistic and literary bohemia. He describes the decline of the traditional patrician order and the rise of a new class of men, dominant on the social, the economic and the political level. Hermeneutic because an ever questioning attitude and a desire for absolute truths are at the heart of powell's writing. The open-endedness of the series is in keeping with the aporia which is an integral part of the quest for truth. For powell's narrators, fellow humans remain fundamentally inscrutable, inaccessible and meaning for ever elusive. The author's imaginary universe is dominated by an aesthetics of uncertainty and permeated by an overwhelming feeling of malaise. Existential vacuity, linguistic inanity, pervasive images of imprisonment, physical and emotional disorders lend his novels an essentially dysphoric tone. The richness of powell's comic invention and in particular his gentle humour temper the overall atmosphere of gloom. These elements enable the reader to come to terms with powell's lucid perception of the absurdity of the world
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Kim, Michael 1973. "Experiments on powder metals." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47843.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1998.Includes bibliographical references (leaves 138-142).
This thesis describes an experimental program aimed at the development of elastic-plastic constitutive relations for cold compaction of ANCOR MH-100 iron powder. A systematic experimental program consisting of triaxial compression, torsion ring shear, uniaxial strain compression, and simple compression test systems has been conducted to investigate the room temperature deformation response of powders ranging from a relative density of n = 0.4 - 0.9. A torsion ring shear apparatus has been designed and fabricated to investigate the frictional behavior of iron powder. The torsion ring shear apparatus is also used to examine the important interface frictional behavior between the powder compact and confinement dies.
by Michael Kim.
S.M.
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Sliwinski, Peter R. "Powder painting of aluminium." Thesis, Aston University, 1985. http://publications.aston.ac.uk/14478/.
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The mechanisms involved in the production of chromate-phosphate conversion coatings on aluminium have been investigated. A sequence of coating nucleation and growth has been outlined and the principle roles of the constituent ingredients of the chromate-phosphate solution have been shown. The effect of dissolved aluminium has been studied and its role in producing sound conversion coatings has been shown. Metallic contamination has been found to have a dramatic influence on chromate-phosphate coatings when particular levels have been exceeded. Coating formation was seen to be affected in proportion to the level of contaminaton; no evidence of sudden failure was noted. The influence of substrate and the effect of an acidic cleaner prior to conversion coating have been studied and explained. It was found that the cleaner ages rapidly and that this must .be allowed for when attempting to reproduce industrial conditions in the laboratory. A study was carried out on the flowing characteristics of polyester powders of various size distributions as they melt using the hot-stage microscopy techniques developed at Aston. It was found that the condition of the substrate (ie extent of pretreatment), had a significant effect on particle flow. This was explained by considering the topography of the substrate surface. A number of 'low-bake' polyester powders were developed and tested for mechanical, physical and chemical resistance. The best formulation had overall properties which were as good as the standard polyester in many respects. However chemical resistance was found to be slightly lower. The charging characteristics of powder paints during application by means of electrostatic spraying was studied by measuring the charge per unit mass and relating this to the surface area. A high degree of correlation was found between charge carried and surface area, and the charge retained was related to the powder's formulation.