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SHVARTSMAN, VLADIMIR A. "MULTICHANNEL COHERENT PM-PM SYSTEM FOR TELEMETRY." International Foundation for Telemetering, 1986. http://hdl.handle.net/10150/615538.
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International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, NevadaThe introduction of a phase/frequency-locked loop (PFLL) technique made the task of transmitting information with a high degree of accuracy less cumbersome. The PFLL became possible after a high precision, continuous type phase/frequency-to-voltage converter/demodulator (PFVCD) was developed. It performance at a wide frequency band (DC-80 KHz), dynamic range up to 120 dB, and precision pulse width discrimination has made possible to build fast hopping PFLL based coherent timemultiplex PM-PM system with only few tenths of a degree of radians spacing between channels. A parallel type decoder was built to demodulate and separate individual channels. It employed the PFVCD which n-shape (ideal) bandpass characteristic and high level linearity eliminates crosstalk and minimizes distortion of an original signal.
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Busse, Ralf. "Wahrnehmung, Indexikalität und Reflexion Hector-Neri Castañedas Ontologie und Wahrnehmungstheorie und die Möglichkeit einer phänomenologischen Reflexion." Frankfurt [Main i.e.] Heusenstamm Paris Ebikon Lancaster New Brunswick Ontos-Verl, 2003. http://www.ontos-verlag.de/Buchreihen-PM-Busse.html.
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Gallupe, Gary. "FM, PM and NPR Calculations." International Foundation for Telemetering, 1993. http://hdl.handle.net/10150/608853.
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International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, NevadaSystem performance can be ascertained via a number of parameters; one of which is Signal-to-Noise ratio (SNR). SNR is the ratio of the value of the signal to the value of the noise. It is generally expressed in decibels and usually a function of the system bandwidth. Another measure of performance is the Noise-Power ratio (NPR). NPR is the ratio of the noise level within a specific measurement channel when noise is applied to all channels, to the level that is measured within the specific channel with noise applied to all of the channels but not the specific channel.
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Söderberg, Jansson Marcus, and Oskar Lundkvist. "Property Optimization of PM-gearing." Thesis, KTH, Maskinkonstruktion (Inst.), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209549.
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The purpose of this bachelor thesis is to design and optimize a powder metal gear through FEM-analyzes. The moment of inertia and weight of the gear shall be reduced at the same time as the demands on tension and bending stiffness are met. The gear that is used as reference and will be optimized is the standard gear in the FZG-rig at the department of Machine Design at KTH. The work is initiated with a literary study. After that a CAD-model of the gear and its pinion is created in Solid Edge. Then the reference gear is analyzed in the FEM-program Ansys and control calculations are made according to standards and handbooks. Thereafter different geometry and density variations are made and tested. The tests are then compared to the reference gear. By varying the density of the gear and varying the geometry of the waist of the gear several different optimization proposals could be made. By cutting material off the waist of the gear the weight can be reduced by 6 % with an increase in bending stress of 1 %. If a bigger increase in bending stress is allowed more material can be removed. If the bending stress increase is allowed to be 5 % a decrease in weight and moment of inertia of 14 % is obtained. With an increase in deformation of 5 % a decrease of 11 % in weight and moment of inertia was obtained. The different tested geometries behave relatively equal up to a 3 % decrease in weight with respect to deformation but begins to vary considerably if the weight is further decreased. Removal of material should be symmetric around every gear tooth to avoid transmission failure which also leads to increased noise. The results show that it is better to remove material under each gear tooth rather than under the root. It is also advantageous to remove material close to the flange. Further work is required to analyze and optimize the gears even more. Fatigue tests as well as different load cases should be analyzed.Syftet med kanditatexamensarbetet är att ta fram och egenskapsoptimera ett pulvermetallurgiskt kugghjul med hjälp av FEM-analyser. Tröghetsmomentet och vikten på kugghjulet ska minimeras samtidigt som kraven på spänningar och böjstyvhet uppfylls. Det kugghjul som används som referens och ska optimeras är standardkugghjulet i FZG-riggen på institutionen för maskinkonstruktion på KTH. Arbetet inleds med att en litteraturstudie görs. Sedan tas en CAD-modell för kugghjulet och dess tillhörande drev fram i Solid Edge. Därefter analyseras referenskugghjulet i FEM-programmet Ansys och kontrollberäkningar görs enligt standarder och handböcker. Därefter konstrueras och analyseras olika geometrier och densitetsvariationer och jämförs med referenskugghjulet. Genom att variera densiteten på kugghjulet och variera geometrin på kugghjulets liv kunde flertalet optimeringsförslag tas fram. Genom att göra en utskärning i livet kan vikten minskas med 6 % utan att böjspänningen påverkas mer än 1 %. Om en större ökning i böjspänning tillåts kan ytterligare material avlägsnas. Om böjspänningsökningen tillåts vara ca 5 % kan en viktminskning och tröghetsmomentsminskning på ca 14 % åstadkommas. Vid en deformationsökning på 5 % erhölls en viktminskning och tröghetsmomentsminskning på ca 11 %. De olika geometrier som testas beter sig relativt lika upp till 3 % viktminskning med avseende på deformation och börjar därefter variera kraftigt. Borttagning av material måste ske symmetriskt kring varje kuggtand för att transmissionsfel och därmed ökat buller ska undvikas. Det visar sig att ta bort material under kuggen är bättre än att ta bort material under kuggroten. Det gynnsamt att göra geometriska förändringar närmast flänsen på kugghjulet. Vidare arbete krävs för att analysera och optimera kugghjulen ytterligare. Utmattningstester och fler lastfall bör analyseras.
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Bleyl, H. J. [Verfasser]. "Schnelle radiochemische Trennung Seltener Erdmetalle und einige Kernzerfallsdaten der Nuklide Pm-139, Pm-140, Pm-141, Sm-141, Sm-142, Sm-143 / H. J. Bleyl." Karlsruhe : KIT-Bibliothek, 2012. http://d-nb.info/1190100770/34.
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Apel, Th. "SPC-PM Po 3D --- Users Manual." Universitätsbibliothek Chemnitz, 1998. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-199800836.
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The experimental program ¨SPC-PM Po 3D¨ is part of the ongoing research of the Chemnitz research group Scientific Parallel Computing (SPC) into finite element methods for problems over three dimensional domains. The package in its version 2.0 is documented in two manuals. The User's Manual provides an overview over the program, its capabilities, its installation, and handling. Moreover, test examples are explained. The aim of the Programmer's Manual is to provide a description of the algorithms and their realization. It is written for those who are interested in a deeper insight into the code, for example for improving and extending. In Version 2.0 the program can solve the Poisson equation and the Lam\'e system of linear elasticity with in general mixed boundary conditions of Dirichlet and Neumann type. The domain $\Omega\subset\R^3$ can be an arbitrarily bounded polyhedron. The input is a coarse mesh, a description of the data and some control parameters. The program distributes the elements of the coarse mesh to the processors, refines the elements, generates the system of equations using linear or quadratic shape functions, solves this system and offers graphical tools to display the solution. Further, the behavior of the algorithms can be monitored: arithmetic and communication time is measured, the discretization error is measured, different preconditioners can be compared. We plan to extend the program in the next future by including a multigrid solver, an error estimator and adaptive mesh refinement, as well as the treatment of coupled thermo-elastic problems. The program has been developed for MIMD computers; it has been tested on Parsytec machines (GCPowerPlus-128 with Motorola Power PC601 processors and GCel-192 on transputer basis) and on workstation clusters using PVM. The special case of only one processor is included, that means the package can be compiled for single processor machines without any change in the source files.
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Apel, Th, F. Milde, and M. Theß. "SPC-PM Po 3D --- Programmers Manual." Universitätsbibliothek Chemnitz, 1998. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-199800848.
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The experimental program ¨SPC-PM Po 3D¨ is part of the ongoing research of the Chemnitz research group Scientific Parallel Computing (SPC) into finite element methods for problems over three dimensional domains. The package in its version 2.0 is documented in two manuals. The User's Manual provides an overview over the program, its capabilities, its installation, and handling. Moreover, test examples are explained. The aim of the Programmer's Manual is to provide a description of the algorithms and their realization. It is written for those who are interested in a deeper insight into the code, for example for improving and extending. In Version 2.0 the program can solve the Poisson equation and the Lam'e system of linear elasticity with in general mixed boundary conditions of Dirichlet and Neumann type. The domain $\Omega\subset\R^3$ can be an arbitrarily bounded polyhedron. The input is a coarse mesh, a description of the data and some control parameters. The program distributes the elements of the coarse mesh to the processors, refines the elements, generates the system of equations using linear or quadratic shape functions, solves this system and offers graphical tools to display the solution. Further, the behavior of the algorithms can be monitored: arithmetic and communication time is measured, the discretization error is measured, different preconditioners can be compared. We plan to extend the program in the next future by including a multigrid solver, an error estimator and adaptive mesh refinement, as well as the treatment of coupled thermo-elastic problems. The program has been developed for MIMD computers; it has been tested on Parsytec machines (GCPowerPlus-128 with Motorola Power PC601 processors and GCel-192 on transputer basis) and on workstation clusters using PVM. The special case of only one processor is included, that means the package can be compiled for single processor machines without any change in the source files.
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Friezema, Margreet. "BAAS in eigen baan." Groningen : Groningen : HG, Faculteit bedrijfskunde.afdeling personeelsmanagement ; Hanzehogeschool Groningen [Host], 2007. http://scripties.hanze.nl/2007/SIBK/PM/1.pdf.
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Oostland, Maarten Wielinga Simone Knijff Sanne. "Adviesnota HR student consultancy." Groningen : Groningen : HG, opleiding personeelsmanagement ; Hanzehogeschool Groningen [Host], 2007. http://scripties.hanze.nl/2008/SIBK/PM/1.pdf.
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Sandman, Marieke. "STOP! Ongewenst personeelsverloop!" Groningen : Groningen : HG, Faculteit Bedrijfskunde, Afdeling Personeelsmanagement ; Hanzehogeschool Groningen [Host], 2008. http://scripties.hanze.nl/2008/SIBK/PM/3.pdf.
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Lo, Jeffrey Kin Hung. "Open systems interconnection passive monitor OSI-PM." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29418.
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The Open Systems Interconnection Passive Monitor (OSI-PM), which is based on the principles of the OSI-Reference Model (OSI-RM), provides a framework for the development
of multi-layer passive monitoring and testing. It adopts the same seven-layer architecture of the OSI-RM and provides the capability of selectively displaying, capturing,
and analyzing the protocol events on single or multiple connections for any subset or all of the seven layers. Different from conventional monitors, the OSI-PM is able to detect protocol violation as they occur in addition to the monitoring functions. The current OSI-PM is able to monitor and test up to the transport layer of the OSI-RM. This thesis discusses the design, prototype implementation and testing of the OSI-PM.Science, Faculty of
Computer Science, Department of
Graduate
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Woolaghan, Stephen John. "Current source inverters for PM machine control." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/current-source-inverters-for-pm-machine-control(cf31f106-f7b5-475d-a5c1-8da80c06fc8a).html.
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Brushless permanent magnet (PM) drive systems offer a high efficiency over a wide power/torque-speed operating envelope, however, there are a number of problems that may limit, or complicate, their operation particularly in automotive and aerospace vehicular applications, i.e. the loss of control of the power silicon gate drive circuitry during fluxweakening operation, control of high-speed low-inductance machines and the presence of large electrolytic capacitors on the inverter DC link. Current Source Inverters (CSIs) could potentially address some or all of the above issues. However, they have found little application to date due to the wide use of the Voltage Source Inverter (VSI) circuit topology.This thesis investigates feasibility of utilising Current Source Inverters (CSIs) to control permanent magnet synchronous machines in automotive and aerospace actuation systems. CSIs, switching at the fundamental frequency, were used in some of the first semiconductor based, electronic variable speed drive systems that utilised the simple, low maintenance AC induction motor. However, the rapid progress of semiconductors and discovery of Pulse Width Modulation (PWM) techniques soon resulted in the Voltage Source Inverter (VSI) replacing the CSI in all but the highest power applications. Modern power electronics and (micro-processor based) control systems mean that the advantages of VSI systems may no longer be significant and combined with the unique environmental conditions that automotive and aerospace applications present, could allow the CSI to offer advantages over VSIs in these applications.The thesis presents the switching and control logic for CSIs and mapping to the more conventional VSI logic. Analysis is made of the various loss mechanisms in VSI and CSI power circuitary. Simulation models of the VSI and CSI structures are presented and representative drive systems designed, built and tested to validate the model developed. Comparisons are made of the two inverter topologies based on power conversions and loss audits of the test validation hardware.
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Liu, Di. "Integral Measurement of Atmospheric Particulate Matter (PM)." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5573.
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Atmospheric aerosol particles also known as atmospheric particulate matter or particulate matter (PM) are microscopic particles (solid or liquid) suspended in air, which is one of six air pollutants in US air quality standard. PM is classified as coarse particles with diameters between 2.5 to 10 mm, fine particles with a diameter less than 2.5 mm (PM2.5), and ultrafine particles with the diameter less than 0.1 mm (PM0.1). Epidemiological studies have already showed the adverse health effects (such as asthma, lung cancer and respiratory and cardiovascular disease) resulted from exposure to the fine and ultrafine particles. Monitoring the PM concentration (i.e., either mass or surface area concentration of PM) is critical for the protection of public health and environment and for the regulatory control. Various PM sensors are now available in market. A majority of these PM sensors are optical sensors, whose readouts are highly depended on the physical property and composition of PM. Several PM monitors based on the measurement principle of electrical charging are also available. However, the empirical calibration of the readout of these electrical PM monitors via the use of standard dust particles makes it difficult to obtain the true mass concentration of PM when PM size distribution is different from that of standard dust.
The overall objective of this dissertation is to advance our scientific knowledge on the performance of cost-effective PM monitors for measuring either mass or surface area concentration of fine and ultrafine PM. This thesis includes two parts: (1) is on the evaluation of existing PM sensor for PM mass concentration measurement; (2) is on the development of new PM monitor for PM surface area concentration measurement. For the first part of this dissertation, four low-cost optical sensors, one Personal Dust Monitor (PDM) and DustrakTM were experimentally evaluated. Particles in the size distribution having different mean size, standard deviation value and material were used as test aerosol particles. The readouts of these low-cost and portable sensors are compared to that of a standard TEOM (Tapered Element Oscillation Microbalance). For the second part of this dissertation, a new electrical PM monitor, consisting of a corona-based aerosol charger, a precipitator and high sensitive current meter, has been proposed for measuring surface area concentration of fine and ultrafine PM. Particles are electrically charged upon entering an electrical PM monitor. Instead of using Faraday cage and current meter to measure the charges carried by particles in existed electrical PM sensors, the new PM monitor measures the current carried by particles deposited directly on the wall of the precipitator. A thorough evaluation has been carried out to evaluate the fundamental performance of this new PM monitor. In addition, small cyclones (i.e., quadru-inlet and tapered-body cyclones) were also evaluated as the size-selective inlet of these PM sensors/monitors to minimize the potential interface from the presence of PM with large sizes in the air. The small quadru-inlet cyclone is to resolve the issue of directional sampling; and the tapered-body cyclones is to reduce the cyclone pressure drop while having small cyclone cutoff particle size. Each cyclone has been evaluated via the measurement of particle penetration curve and pressure drop. Semi-empirical models have been obtained for the prediction of cyclone performance.
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Fornasiero, Emanuele. "Advanced design of direct drive PM machines." Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3426954.
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The following thesis takes into consideration some aspects regarding the design of permanent magnet machines.
The growing interest in this type of emachines is due to certain characteristics that they present: high torque density, possibility of eliminating the gear-box and then subsequent reduction of costs and maintenance, etc..
Many applications are found in the field of wind generators, electric traction and rope traction.
The special construction of such machines, such as the presence of fractional-slot windings, the large size and large powers that they may present, lead to the need of considering some issues often not properly investigated during the machine design.
To this aim, the thesis examines the following two aspects: the rotor losses in machines with fractional-slot windings and the fault tolerance.Il seguente lavoro di tesi prende in considerazione alcuni aspetti riguardanti il progetto di macchine a magneti permanenti. Il crescente interesse rivolto a questo tipo di macchine è dovuto ad alcune caratteristiche che esse presentano: alta densità di coppia, possibilità di eliminazione del riduttore di giri e quindi conseguente riduzione di costi e manutenzione, ecc. Molte applicazioni si trovano nel campo della generazione eolica, della trazione elettrica e della trazione a fune. Le particolarità costruttive di tali macchine, quali ad esempio la presenza di avvolgimenti a cave frazionarie, le notevoli dimensioni e le grosse potenze che esse possono presentare, portano a dover considerare alcune problematiche spesso non propriamente investigate durante la progettazione. A questo scopo, il lavoro di tesi analizza i seguenti due aspetti: le perdite rotoriche in macchine con avvolgimenti frazionari e la tolleranza ai guasti.
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Dasadhikari, Kingshuk. "Attribution of PM₂.₅ Health Impacts in Asia-Pacific." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/120383.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2018.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 57-63).
Asia-Pacific anthropogenic emissions have changed rapidly in recent years due to industrialization, increasing mobility, and emissions controls. Although these changes have altered the region's burden of premature mortalities due to ambient fine particulate matter (PM₂.₅), the contribution of each sector and effectiveness of different policy measures has not yet been quantified. Such data would inform future decision-making on both policy effectiveness and the relative importance of controlling emissions from different sectors. This study estimates changes in regional anthropogenic emissions by industrial sector between 2010 and 2015, based on sector-level activity indicators and enacted emission controls. These factors are applied to an existing high-resolution emissions inventory for 2010 to estimate emissions up to 2015. Using a chemical transport model, the effects of changes in each sector's contribution to total PM₂.₅-driven premature mortalities are calculated for 2010 - 2015, in addition to the total contribution of each sector to premature mortality in 2015. 2,000,000 (95% CI: 1,740,000-2,260,000) annual global PM₂.₅-driven premature mortalities are attributed to Asia-Pacific anthropogenic sectoral emissions in 2015. The agricultural, industrial, and residential sectors constitute the top three sources of these total impacts. Between 2010 and 2015, sustained economic and activity growth, particularly in South and Southeast Asia, have led to 129,000 (95% CI: 106,000-166,000) additional annual premature mortalities, primarily across India, Indonesia, and Bangladesh. The energy and industrial sectors, in particular, cause 38,000 and 45,000 additional annual premature mortalities across these three countries respectively. Simultaneously, falling activity rates in other countries due to structural changes such as electrification of railroads, as well as newly introduced abatement measures over this period, including China's Action Plan on the Prevention and Control of Air Pollution as well as region-wide adoption of Euro IV/V/VI-compliant road vehicle emission and fuel quality standards have led to a total reduction of 95,000 (95% CI: 76,000-129,000) annual premature mortalities, primarily across East Asia, including China and Japan. These opposing drivers result in a net change of an additional 34,000 (95% CI: 23,000-47,000) PM2.5-driven annual premature mortalities between 2010 and 2015 due to Asia-Pacific anthropogenic emissions.
by Kingshuk Dasadhikari.
S.M.
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Ananthanarayanan, V. "Diffusion welding of an RS/PM aluminum alloy /." The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487588249822801.
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Silva, Pedro Miguel Agostinho. "Contributo e caracterização de PM da ressuspensão rodoviária." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/15801.
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Mestrado em Engenharia do AmbienteNos últimos anos, tem-se assistido a um crescimento no interesse do estudo da ressuspensão de pó de estrada, dado o reconhecimento da importância que esta fração representa para os níveis de partículas atmosféricas em ambiente urbano. Dada a prematuridade deste tema e, de forma a compreender e conhecer a sua contribuição e caracterização, realizou-se um estudo sobre a ressuspensão de pó de estrada urbano para as cidades do Porto e Braga. No âmbito do projeto AIRUSE e URBE, realizaram-se amostragens de PM10 no terreno com um dispositivo de amostragem móvel e em ambiente laboratorial com uma câmara de ressuspensão, sendo posteriormente analisado o seu conteúdo carbonoso por um sistema de análise termo-ótico de transmitância e, os elementos por ICP-MS e ICP-AES. Da campanha in situ resultaram cargas de PM10 compreendidas entre 0.190 e 49.5 mg.m-2 para a cidade do Porto e 0.577 mg.m-2 para o túnel rodoviário em Braga. As amostras caracterizam-se por serem dominadas pelos elementos Al, Fe, K, e Ca e conterem enriquecimentos de Sb, Fe, Cu, Sn e Zn, fruto da contaminação antropogénica da atividade rodoviária. No que respeita às amostragens em laboratório, utilizou-se uma câmara de ressuspensão e o dispositivo móvel aplicado na campanha anteriormente descrita para estudar e caracterizar a fração PM10 do pó de estrada urbano proveniente do Túnel Avenida da Liberdade (Braga). Os resultados obtidos para as duas metodologias foram de um modo geral similares, com o carbono total a representar cerca de 6% da massa total de PM10. Esta última é composta maioritariamente por Al, Fe, Ca e K, elementos característicos da crosta terrestre. Quanto ao fatores de enriquecimento calculados, denotou-se a presença de Sb, Zn, Cu e Sn, tendo-se associando ao desgaste dos travões e pneus.
In recent years, road dust studies interest has been growing, due its recognition as a major contributor to the levels of airborne particles in the urban environment. Given the premature knowledge on this issue and in order to access its contribution and characterization, urban road dust sampling trials were taken in the cities of Oporto and Braga. Within the AIRUSE and URBE projects, in site PM10 samplings were taken with a mobile sampling device and in a laboratory environment by means of a resuspension chamber, with its carbonaceous content being analyzed by a thermo-optical analysis system and its elements by ICP-MS and ICP-AES. The field campaign resulted in PM10 surface loadings of 0.190 to 49.5 mg.m-2 in Oporto and 0.577 mg.m-2 for the road tunnel at Braga. Samples were dominated by Al, Fe, K and Ca and enriched with Sb, Fe, Cu, Sn and Zn, due to the anthropogenic contamination from traffic activity. With regard to the laboratory sampling, a resuspension chamber and the mobile sampling device previously announced were applied to study the PM10 fraction of urban road dust derived from the Avenida da Liberdade tunnel. The obtained results for the two methods were generally similar, with its total carbon content being on average 6% of the total PM10 mass. The latter was mainly composed of Al, Fe, Ca and K, associated with typical upper crust elements. The presence of Sb, Zn, Sn and Cu were found as the most enriched elements, and were attributed to the brake lining and tire wear.
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Piga, Enrico <1992>. "Home Bias: PLS PM application on banking sector." Master's Degree Thesis, Università Ca' Foscari Venezia, 2017. http://hdl.handle.net/10579/11553.
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This thesis aims to analyse banking sector in north-east of Italy, more precisely Cooperative Credit Banks connected with the phenomenon of Home Bias. In literature, many studies detected different causes of home bias both from a client and bank point of view, namely geographical factors related to widespread presence in small territories, cognitive errors in portfolio asset allocation caused by low diversification, political factors and costs in international financial markets. The thesis accompanies theoretical concepts with a quantitative analysis on a real dataset on which the application of Structural Equation Models, in the specific Partial Least Squared with different approaches. Furthermore, in light of heterogeneity in the dataset, we try to implement previous models in order to be in line with theory, obtaining homogeneous classes. Finally, mediating effect are considered and quantified as source deviation of relationships inside estimated model. The thesis is organised as follow. Chapter I introduces the basic concepts of Asset Allocation linked to home basis and ending with literature of possible causes. Chapter II describes banking sector and regulation in Italy. Introduction of PLS PM approach is exposed in Chapter III. Chapter IV contains the analysis of the dataset with descriptive statistics. In Chapter V PLS PM approach is applied on dataset. Heterogeneity in the dataset and the use of REBUS PLS to detect homogeneous classes are presented in Chapter VI. Chapter VII focuses on detecting possible moderating effects in PLS PM estimated on previous chapters. We conclude in Chapter VIII with comments on results and reflections.
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Burkhardt, Yves [Verfasser]. "Optimierter Entwurf hocheffizienter PM-Spaltrohrmotoren für Pumpenapplikationen / Yves Burkhardt." Aachen : Shaker, 2011. http://d-nb.info/1070151181/34.
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Acquaviva, Alessandro. "Analytical Modeling of Iron Lossesfor a PM Traction Machine." Thesis, KTH, Elektrisk energiomvandling, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105477.
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Permanent magnet (PM) machines offer several advantages in traction applications such as high efficiencyand high torque per volume ratio. The iron losses in these machines are estimated mostly with empiricallaws taken from other types of machines or with finite element simulations (FEM). In the first part of thisthesis the objective is to define an accurate analytical model for the stator yoke, teeth and rotor of a PMmotor which should work well enough for all operating point (different loads and frequency).This analytical model is found using an iterative process. After building a loss matrix and flux matrix basedon FEM simulations, it is possible to curve fit each of the lines or the rows of the matrix in order to achievethe best fitting for every operating point. This is a very new approach; it was shown that it gives thepossibility, even with a very limited number of FEM simulations, to achieve an accurate estimation of thelosses.The second part of this report focuses on optimizing this analytical method, comparing it with otherpossibilities, analyzing limits and advantages. Special attention is also given to the effects of the losses onthe temperatures in different parts of the machine. In the last part of the thesis, the analytical model isused to test a new control strategy. Its goal is to reduce the total losses of the motor and optimize the ratiobetween torque and total losses for a given driving cycle.
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Rynkiewicz, Mateusz. "Design of PM generator for avertical axis wind turbine." Thesis, Uppsala universitet, Elektricitetslära, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-177309.
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The task in this project is to design a generator for a vertical axis wind turbine withpower rated to 20kW at a wind speed of 10m/s. The project is conducted at theDivision of Electricity at Uppsala University with collaboration from ElectricGeneration AB. The design has just a few moving parts, which decreases maintenancecosts and increases its toughness. The turbine absorbs wind from every direction butits rotation speed ratio is lower than horizontal axis wind turbines. It means that thegenerator must be bigger and therefore more expensive. Price is an importantcriterion for the generator. Neodymium magnets are expensive so the amount of thismaterial must be limited.Several designs have been simulated but one final design has proven the mostpromising. It fulfills all specifications such as efficiency above 95%, 20kW outputpower and it also has a relatively low amount of hard magnetic material.A design with a single row of cables per slot was decided upon to eliminate heatpockets between cable rows, which can occur in designs with two cable rows perslot. It would be interesting to study designs with two or more cable rows per slot, asit could lead to a smaller and more efficient machine.
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Zhang, Ruoju, and 張若菊. "A new PM hybrid motor drive for electric vehicles." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31472849.
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He, Jiawei [Verfasser]. "Hochtourige Antriebskonzepte für Strömungsmaschinen in PM-Synchrontechnik / Jiawei He." Düren : Shaker, 2020. http://d-nb.info/1222396068/34.
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Garcia, Gonzalez Adolfo. "Magnet Losses in Inverter-fed High-speed PM Machines." Thesis, KTH, Elektrisk energiomvandling, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177641.
Full textAbstract:
This master thesis deals with the estimation of magnet losses in a Permanent Magnet(PM) motor inserted in a nut-runner. This type of machine has interesting featuressuch as being slot-less and running at a very high speed (30000 rpm). An extensiveliterature review was performed in order to investigate the state of the art in estimationof the losses in magnets of a PM machine. Analytical models to calculate the no-loadback-emf and the magnetic ux density in the air-gap due to the currents in the statorare presented rst. Furthermore, several of the analytical models for calculating lossesin magnets described in the literature were tested and adapted to the case of a slotlessmachine with a parallel-magnetized ring. Then, a numerical estimation of thelosses with nite element method (FEM) 2D was carried out. In addition, a detailedinvestigation of the eect of simulation settings (e.g., mesh size, time-step, remanentmagnetic ux density in the magnet, superposition of the losses, etc.) was performed.Finally, calculation of losses with 3D FEM are also included in order to compare thecalculated losses with both analytical and FEM 2D results. The estimation of thelosses includes the variation of these with frequency for a range of frequencies between10 and 100 kHz.Detta examensarbete handlar om uppskattningen av magnetforluster i en permanentmagnetmotor (PM) inford i en mutterdragare. Denna typ av maskin har intressantafunktioner, som att den ar slot-less och att den kors i en hog hastighet (30000rpm). En omfattande litteraturstudie utfordes for att kunna uppskatta forluster imagneterna pa basta satt. Forst presenteras analytiska modeller for att berakna denelektromotoriska kraften (EMK) och den magnetiska odestatheten i luftgapet somuppkommer pa grund av strommarna i statorn. Dessutom har era av de analytiskamodellerna for berakning av forlusterna som beskrivits i litteraturen testats och anpassatstill en slot-less maskin med en parallelmagnetiserad ring. En numerisk uppskattningav forlusterna har sedan utforts med hjalp av nita elementmetoden (FEM) 2D.Dartill har en detaljerad undersokning genomforts hur olika parameterinstallningarpaverka utfallet. De FEM parametrar som har undersokts har bland annat bestattav berakningsnatets storlek, tidssteg, remanens odestatheten i magneten och om superpositionav forlusterna galler. Till sist har berakningar for forluster med 3D FEMutforts och jamforts med resultaten for bade de analytiska och FEM 2D resultaten.Uppskattning av forluster innefattar variationen av dessa med ett frekvensomrade mellan10 och 100 kHz.
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Živěla, Roman. "Optimalizace činností techniků specialistů při zavádění pilíře PM WCM." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2011. http://www.nusl.cz/ntk/nusl-264866.
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This master’s thesis deals with the determination of conditions and the proposal of appropriate instruments within the World Class Manufacturing system (WCM), mainly its pillars Professional Maintenance (PM), in order to remove, with the assistance of subsequent analysis, all the waste which occurs in the enterprise and consequently to appropriately optimise the activities of staff, especially the specialized engineers.
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Deirmina, Faraz. "Novel PM Tool Steel with improved hardness and toughness." Doctoral thesis, Università degli studi di Trento, 2017. https://hdl.handle.net/11572/368422.
Full textAbstract:
Ultrafine grained (~ 1μm) steels have been the subject of extensive research work during the past years. These steels generally offer interesting perspectives looking for improved mechanical properties. UFG Powder Metallurgy hot work tool steels (HWTS) can be fabricated by high energy mechanical milling (MM) followed by spark plasma sintering (SPS). However, similarly to most UFG and Nano-Crystalline (NC) metals, reduced ductility and toughness result from the early plastic instabilities in these steels. Industrialization of UFG PM Tool Steels requires the application of specific metallurgical tailoring to produce tools with sound mechanical properties or in a more optimistic way, to break the Strength-Toughness “trade-off†in these materials. Among the possible ways proposed to restore ductility and toughness without losing the high strength, “Harmonic microstructure†design seems to be a very promising endeavor in this regard. Harmonic microstructure materials consist of a tunable volume fraction of evenly spaced “isolated†coarse-grained particles (CG) surrounded by a 3D interconnected network of UFG particles. CGs provide ductility and toughness, while high strength is guaranteed by the interconnected network of UFGs. This peculiar design offers an extra work hardening due to the generation of geometrically necessary dislocations at the interfaces of UFGs and confined CGs that are essentially present to accommodate the strain gradient imposed by the inhomogeneous (bimodal grained) microstructure.
The first part of this work is devoted to the development of PM tool steels with harmonic microstructure. Due to the difficulties of processing hard tool steel particles according to the methods reported in the literature, an economical, simple alternative approach is also proposed. Near full density “Harmonic structure“ AISI H13 samples were produced using different volume fractions of UFG/NC mechanically milled (MM) and CG as-atomized particles followed by short time (30 min) low-temperature (1100°C) SPS. A combination of high hardness and significantly improved fracture toughness was achieved for the blends containing more that 50% UFG particles. The optimized mechanical properties was achieved by the mixture of 60% UFG particles where the sample showed a hardness near to the value predicted by the rule of mixtures (i.e. 405 HV10 vs. 406 HV10) while apparent fracture toughness (Kapp) was about 10% higher than that of predicted by the same rule (i.e. 52.0 MPa*m1/2 vs. ~47.0 MPa*m1/2). A toughening effect was evidenced for the samples essentially showing harmonic microstructure. Toughening was interpreted to be the result of the deviatory effect of coarse-grained round atomized particles together with energy dissipation by decohesion at the CG/UFG or UFG/UFG interfaces leading to a local drop of the driving force for the crack propagation. The design allowed to easily adjust the strength and toughness to meet the specific application-oriented requirements. The harmonic steel was also subjected to Thermal Fatigue (TF) testing. The preliminary results confirmed that this microstructure combined the beneficial effects of both of its constituents, i.e., the low crack nucleation rate of CG H13 and the low crack propagation rate of UFG H13, thus showing the lowest pyrocracking factor. Moreover, TF crack deflection as an extrinsic toughening mechanism was evidenced in Harmonic Microstructure.
The second part of this work deals with the production and characterization of a PM HWTS reinforced with partially stabilized zirconia (PSZ). HWTS composites show improved hardness and remarkable wear resistance but generally also a systematic lower fracture toughness than the base material. Deteriorated toughness in metal matrix composites (MMCs) with a high strength matrix is mainly interpreted as a result of early damage initiation at the hard particles (HPs) or Matrix-HP interface. This damage can be even anticipated in the presence of readily damaged HPs (i.e. processing related flaws). Selection of PSZ as reinforcement was aimed at improving the strength and fracture toughness of the composite by taking advantage of the transformation toughening effect of PSZ. Two different types of PSZ, different volume fractions (10 and 20 vol. %) and sizes of reinforcement were used. Mechanical Alloying (MA) was used to process the composite powders to refine the matrix microstructure and both the matrix and PSZ particle size hence increasing the strength of the PSZ particles according to the Griffith strength formalism, and also to overcome the aggregation problems. Powders were consolidated by (SPS). The influence of processing parameters on density and microstructure was investigated. Short time (30 min) low-temperature (1100°C) consolidation by SPS allowed preserving the refined microstructure while achieving a maximum relative density of 98.6%. Moreover, short time sintering did not allow the extensive formation of thermodynamically plausible reaction products at the PSZ-H13 interface. As a result of dispersion hardening, the hardness of the as-sintered composites (i.e. maximum hardness of ~ 920 HV10) was increased compared to the mechanically milled UFG H13 (i.e. ~ 755 HV10), while in comparison to the as-atomized H13 (i.e. ~ 640 HV10) the improved hardness was ascribed to the synergic effect of dispersion hardening, microstructural refinement and strain hardening induced by MA. In these composites, tempering resistance at 550°C and 650°C was significantly improved due to the dispersion hardening effect. The hot compressive yield strength of the composites at 650°C and 450°C was increased up to 1.8 times the unreinforced UFG H13. t to m transformation during hot compression was evidenced and contributed to the strengthening. The hardness of the composites in heat treated condition (i.e. ~ 600 HV10) was significantly improved compared to that of the unreinforced matrix (i.e. ~ 420 HV10) while the apparent fracture toughness was drastically decreased to half the Kapp of the base material (19 MPa*m1/2 vs. 36 MPa*m1/2). However, the fracture toughness was slightly higher than that of a TiC reinforced H13 (i.e. 17 MPa*m1/2) with the same hardness (i.e. ~ 600 HV10).
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Deirmina, Faraz. "Novel PM Tool Steel with improved hardness and toughness." Doctoral thesis, University of Trento, 2017. http://eprints-phd.biblio.unitn.it/2616/1/Thesis_Faraz_Deirmina_eprints.pdf.
Full textAbstract:
Ultrafine grained (~ 1μm) steels have been the subject of extensive research work during the past years. These steels generally offer interesting perspectives looking for improved mechanical properties. UFG Powder Metallurgy hot work tool steels (HWTS) can be fabricated by high energy mechanical milling (MM) followed by spark plasma sintering (SPS). However, similarly to most UFG and Nano-Crystalline (NC) metals, reduced ductility and toughness result from the early plastic instabilities in these steels. Industrialization of UFG PM Tool Steels requires the application of specific metallurgical tailoring to produce tools with sound mechanical properties or in a more optimistic way, to break the Strength-Toughness “trade-off” in these materials. Among the possible ways proposed to restore ductility and toughness without losing the high strength, “Harmonic microstructure” design seems to be a very promising endeavor in this regard. Harmonic microstructure materials consist of a tunable volume fraction of evenly spaced “isolated” coarse-grained particles (CG) surrounded by a 3D interconnected network of UFG particles. CGs provide ductility and toughness, while high strength is guaranteed by the interconnected network of UFGs. This peculiar design offers an extra work hardening due to the generation of geometrically necessary dislocations at the interfaces of UFGs and confined CGs that are essentially present to accommodate the strain gradient imposed by the inhomogeneous (bimodal grained) microstructure.
The first part of this work is devoted to the development of PM tool steels with harmonic microstructure. Due to the difficulties of processing hard tool steel particles according to the methods reported in the literature, an economical, simple alternative approach is also proposed. Near full density “Harmonic structure“ AISI H13 samples were produced using different volume fractions of UFG/NC mechanically milled (MM) and CG as-atomized particles followed by short time (30 min) low-temperature (1100°C) SPS. A combination of high hardness and significantly improved fracture toughness was achieved for the blends containing more that 50% UFG particles. The optimized mechanical properties was achieved by the mixture of 60% UFG particles where the sample showed a hardness near to the value predicted by the rule of mixtures (i.e. 405 HV10 vs. 406 HV10) while apparent fracture toughness (Kapp) was about 10% higher than that of predicted by the same rule (i.e. 52.0 MPa*m1/2 vs. ~47.0 MPa*m1/2). A toughening effect was evidenced for the samples essentially showing harmonic microstructure. Toughening was interpreted to be the result of the deviatory effect of coarse-grained round atomized particles together with energy dissipation by decohesion at the CG/UFG or UFG/UFG interfaces leading to a local drop of the driving force for the crack propagation. The design allowed to easily adjust the strength and toughness to meet the specific application-oriented requirements. The harmonic steel was also subjected to Thermal Fatigue (TF) testing. The preliminary results confirmed that this microstructure combined the beneficial effects of both of its constituents, i.e., the low crack nucleation rate of CG H13 and the low crack propagation rate of UFG H13, thus showing the lowest pyrocracking factor. Moreover, TF crack deflection as an extrinsic toughening mechanism was evidenced in Harmonic Microstructure.
The second part of this work deals with the production and characterization of a PM HWTS reinforced with partially stabilized zirconia (PSZ). HWTS composites show improved hardness and remarkable wear resistance but generally also a systematic lower fracture toughness than the base material. Deteriorated toughness in metal matrix composites (MMCs) with a high strength matrix is mainly interpreted as a result of early damage initiation at the hard particles (HPs) or Matrix-HP interface. This damage can be even anticipated in the presence of readily damaged HPs (i.e. processing related flaws). Selection of PSZ as reinforcement was aimed at improving the strength and fracture toughness of the composite by taking advantage of the transformation toughening effect of PSZ. Two different types of PSZ, different volume fractions (10 and 20 vol. %) and sizes of reinforcement were used. Mechanical Alloying (MA) was used to process the composite powders to refine the matrix microstructure and both the matrix and PSZ particle size hence increasing the strength of the PSZ particles according to the Griffith strength formalism, and also to overcome the aggregation problems. Powders were consolidated by (SPS). The influence of processing parameters on density and microstructure was investigated. Short time (30 min) low-temperature (1100°C) consolidation by SPS allowed preserving the refined microstructure while achieving a maximum relative density of 98.6%. Moreover, short time sintering did not allow the extensive formation of thermodynamically plausible reaction products at the PSZ-H13 interface. As a result of dispersion hardening, the hardness of the as-sintered composites (i.e. maximum hardness of ~ 920 HV10) was increased compared to the mechanically milled UFG H13 (i.e. ~ 755 HV10), while in comparison to the as-atomized H13 (i.e. ~ 640 HV10) the improved hardness was ascribed to the synergic effect of dispersion hardening, microstructural refinement and strain hardening induced by MA. In these composites, tempering resistance at 550°C and 650°C was significantly improved due to the dispersion hardening effect. The hot compressive yield strength of the composites at 650°C and 450°C was increased up to 1.8 times the unreinforced UFG H13. t to m transformation during hot compression was evidenced and contributed to the strengthening. The hardness of the composites in heat treated condition (i.e. ~ 600 HV10) was significantly improved compared to that of the unreinforced matrix (i.e. ~ 420 HV10) while the apparent fracture toughness was drastically decreased to half the Kapp of the base material (19 MPa*m1/2 vs. 36 MPa*m1/2). However, the fracture toughness was slightly higher than that of a TiC reinforced H13 (i.e. 17 MPa*m1/2) with the same hardness (i.e. ~ 600 HV10).
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Morisseau, Kevin. "Traitement combiné de polluants atmosphériques par filtration et adsorption pour limiter leur transfert dans l'habitat urbain." Thesis, Nantes, Ecole des Mines, 2016. http://www.theses.fr/2016EMNA0292/document.
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Avec le développement des bâtiments basse consommation de plus en plus hermétiques, la nécessité de renouveler l’air intérieur à l’aide de système de ventilation mécanique s’est accrue. Or, les concentrations en polluants dans les environnements urbains augmentent continuellement, favorisant ainsi le transfert de polluants atmosphériques dans l’air intérieur. Ces travaux de thèse porte sur l’étude de procédés pour l’élimination combinée des principaux polluants de l’air extérieur urbain entrant dans les logements individuels via les systèmes de ventilation. A l’issue d’un état de l’art des polluants de l’air, des systèmes de ventilation et des procédés de traitement, les procédés de filtration par médias fibreux et d’adsorption ont été choisis pour traiter l’air urbain caractérisé par les PM₁₀, les PM₂ ₅, les aérosols microbiens, les BTEX et les NOₓ. Une méthodologie a été mise en œuvre pour sélectionner parmi différents matériaux étudiés et selon des critères de performances la solution de traitement la mieux adaptée, à savoir un filtre F7-combiné en fibres de verre et contenant des grains de charbon actif. Après étude, une stratégie de chauffage journalier du filtre à 70°C durant 1h30 a été proposée pour régénérer partiellement l’adsorbant afin de prolonger sa durée de vie et pour limiter la croissance microbienne sur le filtre notamment par dessiccation de ce dernier. Une campagne expérimentale en conditions de génération multi-polluants contrôlées a permis de quantifier les performances de traitement du filtre F7-combiné. Le traitement thermique utilisé a permis de maintenir une efficacité d’adsorption du toluène de 40% et de limiter la prolifération microbienne sur le filtre. Des interactions entre les polluants ont été observées, notamment une augmentation de l’efficacité de filtration des PM₁₀ par la présence de PM₂ ₅ qui permettent rapidement le passage à la phase de filtration en surface. En outre, le mélange toluène/NO₂ entraine une diminution de l’adsorption du NO₂ au profit du toluène. Enfin, une campagne expérimentale en conditions réalistes a été menée pendant 3 mois afin notamment d’étudier les performances du traitement thermique. Les niveaux de concentration des polluants dans la zone péri-urbaine de l’étude étaient faibles. Le traitement thermique appliqué au filtre F7-combiné, pour les conditions opératoires étudiées et après 3 mois de suivi, a permis de limiter significativement la croissance fongique sur le filtre mais pas d’améliorer de façon significative l’adsorption des COV et des NOₓThe development of low energy buildings, which are more and more hermetic, leads to the necessity of indoor air renewal with mechanical ventilation system. However, the concentration of pollutants in urban environments increases continually, which promotes the pollutant transfer from the outdoor to the indoor air. This PhD thesis consists in the study of processes for the combined purification of the main urban outdoor air pollutants coming in individual dwellings through the ventilation systems.Out of a state of the art of the air pollutants, the ventilation systems and the treatment processes, filtration with fibrous media and adsorption were the two processes chosen to treat the urban air characterized by PM₁₀, PM₂ ₅, microbialaerosol, BTEX and NOₓ. A methodology was setup to select, through the different studied materials and with some performance criterion, the most suitable treatment solution i.e. a combined-F7 filter with glass fiber and granular activated carbon. A daily heating strategy of the combined-F7 filter at 70°C for 1h30 was proposed to partially regenerate the adsorbent in order to improve its lifetime and to limit the microbial growth on the filter, inparticular by desiccation.An experimental campaign in controlled conditions with multi-pollutant generation permitted to quantify the performances of the combined-F7 filter. The thermal treatment permitted to maintain the adsorption efficiency of the toluene at 40% and to limit the microbial proliferation. Competitions within pollutants were observed, in particular an increase of the filtration efficiency of PM₁₀ with the presence of PM₂ ₅ by promoting the cake filtration stage. Moreover the mix toluene/NO₂ leads to a decrease of the NO₂ adsorption in favor of the toluene.Finally, an experimental campaign in realistic conditions was conducted for 3 months in particular to study the performances of the thermal treatment. Concentration levels of the pollutants in the suburban area of the study were low. The thermal treatment applied to the combined-F7 filter, with the operating conditions studied and after 3month of follow-up, permitted to significantly limit the fungal growth on the filter but it did not permit to improve significantly the VOC and NOₓ adsorption
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Myhr, Monica, and Michaela Nissas. "Handläggning av urinretention postpartum : En kartläggning av svenska förlossningsklinikers PM." Thesis, Högskolan Dalarna, Omvårdnad, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:du-3113.
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Syftet med studien var att kartlägga svenska förlossningsklinikers PM angående urinretention postpartum, samt att studera om dessa överensstämmer med de rekommendationer som återfinns i litteraturen. Chefsbarnmorskan/avdelningschefen på alla svenska förlossningskliniker tillfrågades via e-post och telefon om de kunde skicka in sina PM angående urinretention postpartum. De insamlade dokumenten bearbetades genom kvalitativ och kvantitativ innehållsanalys. De flesta PM förespråkar att bedömning om urinretention föreligger ska ske inom fyra timmar postpartum. I hälften av förlossningsklinikernas PM anges både tappningskateter och ultraljud/bladderscan som diagnosmetod. Endast tre av 28 insamlade PM tar upp omvårdnadsåtgärder som underlättar för kvinnan att tömma blåsan. Åtgärder som föreslogs vid urinretention postpartum varierade beroende på mängd residualurin. Den vanligast förekommande urinmängden för tappning av urinblåsan var mellan 300 och 600 ml och tappningen upprepades var fjärde timme. Avbrytande av tappning när residualurinen understeg 100 ml. När större urinmängder uppmättes valde man att sätta en kateter à demeure. De mest förekommande riskfaktorerna för urinretention postpartum som omnämns i PM är förlängt förlossningsförlopp, epiduralbedövning, instrumentell förlossning och bristningar/perineotomi. Inga klara rekommendationer för handläggning av urinretention postpartum har återfunnits i litteraturen, och vår slutsats är att detta är anledningen till de stora skillnader man ser i PM.
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Norström, Parliden Jonas, and Mateusz Rynkiewicz. "Design of PM generator for a vertical axis wind turbine." Thesis, Uppsala universitet, Elektricitetslära, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-180910.
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The task in this project is to design a generator for a vertical axis wind turbine withpower rated to 20kW at a wind speed of 10m/s. The project is conducted at theDivision of Electricity at Uppsala University with collaboration from ElectricGeneration AB. The design has just a few moving parts, which decreases maintenancecosts and increases its toughness. The turbine absorbs wind from every direction butits rotation speed ratio is lower than horizontal axis wind turbines. It means that thegenerator must be bigger and therefore more expensive. Price is an importantcriterion for the generator. Neodymium magnets are expensive so the amount of thismaterial must be limited.Several designs have been simulated but one final design has proven the mostpromising. It fulfills all specifications such as efficiency above 95%, 20kW outputpower and it also has a relatively low amount of hard magnetic material.A design with a single row of cables per slot was decided upon to eliminate heatpockets between cable rows, which can occur in designs with two cable rows perslot. It would be interesting to study designs with two or more cable rows per slot, asit could lead to a smaller and more efficient machine.
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Kambham, Kalpalatha. "Performance and Total PM Emission Factor Evaluation of Expendable Abrasives." ScholarWorks@UNO, 2006. http://scholarworks.uno.edu/td/385.
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Dry abrasive blasting is one of the most widely used methods of surface preparation. Air emissions from this process include particulate matter (PM) and metals. Spent abrasive generated from this process may be hazardous in nature. With increasing concern on health effects due to silica emissions from sand, use of alternative materials is suggested by health and regulatory agencies. The objective of this research was to evaluate performance of expendable abrasives and determine PM emission factors. Dry abrasive blasting was performed in an enclosed chamber and total PM samples were collected. Three commonly used expendable abrasives, coal slag, copper slag and specialty sand, were used to evaluate cleaner alternatives. Blast pressure and abrasive feed rate, two important process conditions were varied to study their effect on performance of an abrasive. Productivity, consumption and emission factors (performance parameters) were calculated and their variation with pressure and feed rate was evaluated. Two dimensional and three dimensional predicted models were developed to estimate the performance at intermediate blast pressure and feed rate conditions. Performance of the three abrasives was compared with respect to emission potential, productivity and consumption. Emission factors developed in this research will help in accurate estimation of total PM emissions and to select cleaner abrasives and optimum process conditions that will results in minimum emissions and reduced health risk. The productivity and consumption models will help is estimating life cycle costs including material cost, equipment cost, energy cost, labor costs, waste disposal cost, and compliance costs. Consumption models will also help in determining the quantity of spent abrasive generated, identify abrasives with lower material consumption, and identify process conditions that generate minimum spent abrasives. In addition, these models will help industries in making environmentally preferable purchasing (EPP), which results in pollution prevention and cost reduction.
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Löhlein, Bernd [Verfasser]. "Mechatronische Antriebssysteme mit PM-Synchronmaschinen und ihr Entwurf / Bernd Löhlein." Düren : Shaker, 2021. http://d-nb.info/1240853890/34.
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Demir, Selim Tugra. "'AgiLean PM' : a unifiying strategic framework to manage construction projects." Thesis, Liverpool John Moores University, 2013. http://researchonline.ljmu.ac.uk/4509/.
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A challenge in Lean Construction is how to make it applicable when there is a high degree of complexity and uncertainty. In many construction projects there are changing project requirements, unique products and a need for actions that are highly focused on meeting customer/client expectations. Such scenarios require management methods that are characterised by being flexible and able to react to change. The aim of this thesis is to introduce a method that has such characteristics. Project Management, Lean and Agile paradigms are merged through the application of the fission and fusion approach of nuclear physics. This research is facilitated through a sequential explorative method. In the first instance, interviews with 22 practitioners in the fields of construction project management, Lean and Agile have been conducted. Then a quantitative self-administered questionnaire with 213 useful responses has been utilised to validate the transferability of the interview findings. It is concluded that Lean is not ideally suited to dealing with the dynamic nature of construction projects. Agile methods, which were developed to cope with the high levels of uncertainty inherent to IT projects, are more flexible and able to react to change. Hence utilising Agile-based methods might be the key to the successful utilization of Lean in construction. Therefore a management method based on combining Lean and Agile approaches has potential. Such an approach needs creative thinking to develop a solution that is different to that of “Leagile”. Leagile uses Lean and Agile methods in the execution phase sequentially, through using a decoupling point model to separate the two. This thesis introduces a new paradigm in which such a decoupling or separation does not take place. Rather, project management, Lean and Agile have been merged together to develop a new holistic and strategic framework. The paradigm presented in this thesis is termed “AgiLean Project Management”.
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Bergström, Eleonor, and Isa Palme. "Oxytocinbehandling vid värksvaghet : förlossningsklinikers PM följsamhet till de nationella riktlinjerna." Thesis, Sophiahemmet Högskola, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:shh:diva-3833.
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När förlossningsprogressen går långsamt fram eller stannar av helt kan barnmorskan använda sig av läkemedlet Oxytocin® för att framkalla tätare och mer intensiva värkar och på så sätt uppnå progress i förlossning. Oxytocin® är ett potent läkemedel som när det används felaktigt kan ge allvarliga komplikationer för mor och barn. I Sverige togs nationella riktlinjer för oxytocinbehandling vid värksvaghet fram år 2011. Barnmorskan har även lokala riktlinjer att förhålla sig till i sitt dagliga arbete. Studier har visat att oxytocinbehandling sker på ett ostrukturerat sätt i Sverige. Syftet med studien var att undersöka Sveriges förlossningsklinikers PM följsamhet till de nationella riktlinjerna framtagna år 2011 gällande oxytocinbehandling vid värksvaghet. Studien utgjordes av en kvantitativ, komparativ metod med en deskriptiv ansats, där urvalet resulterade i insamlade data från 43 av landets 44 förlossningskliniker. Ett instrument för dataanalys framtogs där samtliga PM jämfördes mot den text som var formulerad i de nationella riktlinjernas föreslagna PM och presenterades genom deskriptiv statistik. Resultatet visade på en variation i följsamhet i de lokala PM:en till de nationella riktlinjerna. Fem klinikers PM överensstämde med de nationella riktlinjernas PM på samtliga punkter. Ytterligare fyra klinikers PM överensstämde på alla punkter förutom gällande riktlinjer kring dokumentation. Knappt två tredjedelar av klinikerna överensstämde till 75 procent eller mer av de punkter som jämfördes i instrument för dataanalys. Ett fåtal klinikers följsamhet var 25 procent eller lägre. Vidare ansågs varken de nationella eller lokala riktlinjerna vara reviderade utifrån den senaste forskningen och evidensen. Studiens slutsats var att kliniker bör se över sina riktlinjer gällande oxytocinbehandling vid värksvaghet för att kunna erbjuda födande kvinnor i Sverige en jämlik och patientsäker vård.
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Hasnain, Bakhtiyar Asef, and Ademir Hodzic. "Design and Simulation of a Slotless Aircored PM Synchronous Generator." Thesis, Uppsala universitet, Institutionen för elektroteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-425268.
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This thesis is a study on an unconventional slow speed direct drive permanent magnet (PM) generator. Unlike a standard permanent magnet synchronous generator (PMSG) which has the copper coils wound around iron teeth, the work in this thesis will present a generator where the copper coils are directly mounted on the stator which eliminates the slots and teeth in the generator. By having a slotless design it is possible to eliminate cogging torque, iron losses in teeth and achieve a lightweight design. These characteristics can prove useful when developing generators for an application such as wind turbines, or more specifically vertical axis wind turbines (VAWTs) in remote areas where weight and serviceability is of concern. This thesis consists of two main parts where the main focus was on the design and simulation of slotless generators. The second part of the thesis was to investigate an available slotless axial flux machine. For the simulations, three different models were created in 2D using CAD software. Two of the models were double-rotor slotless generators and one was a single rotor variant. The electromagnetic properties of these models were analysed using FEMM and COMSOL. The results showed that the double rotor variant with the smaller magnets were more favourable considering the price of magnets and no iron core losses. The experimental results of the axial flux machine gave insight into the construction of commercially available axial slotless generators which could be used to further analyse these types of machines.
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Shivaprasad, Shreyas. "Model Based Investigation of Lean Gasoline PM and NOx Control." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1408970125.
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Sporni, Peter. "Model synchronního stroje s PM založeného na ekvivalentní reluktanční síti." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218792.
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Táto práca pojednáva o problematike vytvárania a simulácie reluktančnej sieti synchrónneho stroja s V tvarovanými permanentnými magnetmi v programe PSpice. Na začiatku sa oboznámime s konštrukciou a parametrami stroja a potom vyvodíme základné rovnice na výpočet každého prvku siete. Vypočítame každý prvok tohto stroja a potom vytvoríme túto sieť v PSpice. Na začiatku je simulovaná sieť statická a všetky magnetické odpory sú lineárne. Neskôr nahradíme lineárne odpory reprezentujúce plechy nelineárnymi a počítame s precovnou teplotou permanentných magnetov. Potom porovnáme naše výsledky s FEM metódou počítanými hodnotami a vypočítame indukované napätie v jednej cievke stroja. Na záver vypočítame výkonovú a momentovú charakteristiku stroja.
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Hedayat, Farzaneh. "Investigation of the molecular probes for PM oxidative capacity measurements." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/98552/1/Farzaneh_Hedayat_Thesis.pdf.
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This thesis improved our understanding of the performance of various assays that are employed to investigate the oxidative potential (OP) of the particulate matter (PM) generated from combustion sources. The OP is expressed through the concentration of reactive oxygen species produced by diesel and biodiesel fuels. Although the combustion of the biofuel generates a lower amount of PM, the particles have a higher OP, with the increase being proportional to the oxygen content of the biofuel. Oxygen content does not only influence the OP of the particle phase but also influences the OP of the gas phase.document.getElementsByName("c12_disable_contact")[0].checked = true;
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Grönvall, Emma. "Kliniska riktlinjer i teori och praktik : En studie vid Sahlgrenska Universitetssjukhuset." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-14184.
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RUSSO, MARA. "Oxidative Potential of Atmospheric Particulate Matter: determination with acellular assays and relationship with samples chemical composition." Doctoral thesis, Università degli studi di Ferrara, 2021. http://hdl.handle.net/11392/2488058.
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The main focus of this PhD thesis is the investigation of the oxidative potential (OP) of ambient particulate matter (PM). This is a biologically relevant metric proposed for assessing adverse health effects related to PM exposure, based on the increasing evidence that they are mostly mediated by the oxidative stress induced by reactive oxygen species (ROS) generated from PM exposure.
The research has been devoted to set up the analytical procedure of acellular assays for measuring OP and to highlight the contribution of chemical components of real PM samples to the OP responses.
The first part of the thesis is aimed to investigate two cell-free assays widely applied to provide the rapid readout of the PM OP. Both are based on the oxidation of target molecules to represent reactions that likely occur in vivo at the air-lung interface: one uses ascorbic acid (AA, OPAA) while the other uses dithiothreitol (DTT, OPDTT). OP response is measured as the antioxidant depletion rate of a known quantity of DTT and AA and provides a quantitative output of PM activity to produce ROS. The effects of two important operating conditions were investigated in detail, namely the solvent used for the PM extraction from sampled filters and the different compositions of antioxidants in the AA assay. The aim was to design an assay set up that most closely simulates the interactions of the inhaled particles when they come in contact with interstitial macrophages in the lung.
In light of the results obtained, the three tested solvents are useful for DTT and AA assays, as generate comparable OP responses, but the phosphate buffer provides the most sensible measure of OP, while among the investigated surrogates, the simplified AA solution shows the advantage of generating higher OPAA, displaying higher sensitivity of the assay response, in comparison with the composite solutions containing two or more physiological AOs.
The central part of the research is committed to the study of the oxidative properties of real PM samples collected in several sites located in different regions across Italy. The aim was to investigate the association of OP responses with PM chemical composition in order to highlight the sensitivity of various acellular OP assays to PM components and identify the emission sources and atmospheric processes that mainly drive the OP assay responses. Although there is a general similarity among different investigated sites, the OPDTTV and OPAAV responses show some differences, in particular between Northern and Southern regions, due to the variation in PM chemical composition, as a consequence of the different impacts of emission sources and atmospheric conditions.
The last part of this thesis regarded the characterization of Polycyclic Aromatic Hydrocarbons (PAHs) in the organic PM composition. These compounds can give important information concerning sources and processes PM undergoes and can assess the toxicological impact. Due to the very large complexity of PM chemical composition, two pre-treatment/purification procedures were used (Solid-Phase Extraction and Solid-Phase Microextraction), as a needed sample pre-treatment to allow to identify and quantify analytes more easily. The comparison between the two procedures shows that the MIP-SPE exceeds in specific selectivity towards hydrocarbon components in PM.
Finally, in the frame of the "Piano Lauree Scientifiche" project, the topic of Indoor Air Quality (IAQ) monitoring was investigated in school classrooms and laboratories in the Emilia-Romagna region (Northern Italy). In each school environment, the IAQ parameters were on-site measured using monitoring sensors operating 24 h continuously, investigating temperature, relative humidity, the concentration of PM2.5, VOCs, and CO2. The daily profile of the concentration of the indoor pollutant was studied, which was related to the activity inside the school’s classroom and the opening/closing of windows and doors.L’obiettivo principale di questa tesi di dottorato è lo studio del potenziale ossidativo (OP) del particolato atmosferico (PM), proposto come metrica biologicamente rilevante per valutare gli effetti negativi sulla salute umana, mediati dallo stress ossidativo indotto dalle specie reattive dell'ossigeno (ROS), in seguito all'esposizione al PM. La ricerca è stata dedicata alla messa a punto della procedura analitica di saggi acellulari per la misurazione del potenziale ossidativo, evidenziando il contributo della componente chimica del PM sulle risposte OP ottenute. La prima parte della tesi è stata dedicata allo studio di due saggi cell-free, ampiamente applicati per fornire la lettura rapida del potenziale ossidativo del PM, basati sull'ossidazione di molecole target, acido ascorbico (AA) e ditiotreitolo (DTT), per rappresentare le reazioni che si verificano all'interfaccia aria-polmone. La risposta OP viene misurata attraverso la velocità di consumo di una quantità nota di DTT e AA e fornisce un output quantitativo dell’attività del PM nella produzione di ROS. Sono stati studiati nel dettaglio gli effetti di due importanti condizioni operative: il solvente utilizzato per l'estrazione del PM dai filtri campionati e le diverse composizioni di antiossidanti nel dosaggio AA. L’obiettivo prefissato era quello di progettare un set-up sperimentale che rappresentasse in modo adeguato le interazioni delle particelle inalate di PM quando entrano in contatto con i macrofagi interstiziali nel polmone. Alla luce dei risultati ottenuti, i tre solventi testati sono utili per entrambi i saggi in quanto generano risposte OP comparabili, anche se il tampone fosfato fornisce una misura OP più attendibile. Tra i surrogati indagati, la soluzione semplificata di AA mostra il vantaggio di generare risposte OPAA più elevate, mostrando una maggiore sensibilità rispetto alle soluzioni composite contenenti due o più antiossidanti fisiologici. La parte centrale della ricerca è stata rivolta allo studio delle proprietà ossidative dei campioni reali di PM raccolti in vari siti in diverse regioni d'Italia, indagando l'associazione delle risposte OP con la composizione chimica del PM al fine di evidenziare la sensibilità dei due saggi acellulari. Sebbene vi sia una somiglianza generale tra i diversi siti indagati, le risposte OPDTTV e OPAAV mostrano alcune differenze, in particolare tra le regioni del Nord e del Sud, dovute alla variazione della composizione chimica del PM come conseguenza dell’impatto delle diverse sorgenti di emissione e delle condizioni atmosferiche. L'ultima parte di questo lavoro di tesi riguarda la caratterizzazione degli Idrocarburi Policiclici Aromatici (IPA) nella composizione del PM organico. Questa classe di composti fornisce importanti informazioni sulle fonti e sui processi a cui è sottoposto il PM e permette di valutarne l'impatto tossicologico. A causa dell’elevata complessità della composizione chimica del PM, sono state utilizzate due procedure di pretrattamento/purificazione (SPE e SPME), per consentire una migliore identificazione e quantificazione degli analiti. Il confronto tra le due procedure evidenzia come la fase SPE costituita dal polimero a stampo molecolare (MIP) risulta maggiormente selettiva nei confronti degli IPA, eliminando le interferenze dovute agli n-alcani. Infine, nell'ambito del progetto "Piano Lauree Scientifiche", è stato approfondito il tema del monitoraggio della Qualità dell'Aria Indoor (IAQ) nelle aule e laboratori di due scuole secondarie di Ferrara. Il monitoraggio è stato condotto in-situ negli ambienti scolastici utilizzando sensori che hanno misurato in continuo: temperatura, umidità relativa, concentrazione di PM2.5, VOCs e CO2. Si è studiato il profilo giornaliero della concentrazione indoor degli inquinanti, il quale è stato messo in relazione sia con l'attività all'interno dell'aula scolastica, sia con l'apertura/chiusura di finestre e porte.
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Calas, Aude. "Pollution atmosphérique particulaire : développement de méthodologies non-invasives et acellulaires pour l’évaluation de l’impact sanitaire." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAU033.
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Grâce à des études de processus in vitro, on a pu montrer que les effets sanitaires des particules atmosphériques (aérosols) sont principalement attribués à leur potentiel inflammatoire via les espèces oxydantes qu’ils véhiculent : métaux et molécules organiques, principalement. Les maladies déclenchées diffèrent ensuite régionalement selon les mélanges spécifiques des différentes sources de pollution, la durée d’exposition et la susceptibilité des personnes. Les paramètres clefs à quantifier sont donc la bioaccessibilité (fraction potentiellement réactive de l’aérosol) et la capacité oxydante intrinsèque des aérosols afin de prédire leur toxicité. A cette fin, des tests non invasifs, c’est-à-dire effectués sur le mélange de polluants lui-même et non pas sur l’individu, ont été récemment développés (Cho et al. 2005; Sauvain et al. 2009; Denys et al. 2009; Li et al. 2003; Uzu et al. 2011). Peut-on les utiliser en l’état alors que la composition chimique des aérosols diffère drastiquement en fonction de l’environnement? On sait notamment que les bactéries présentes dans l’air sont capables d’abaisser la capacité oxydante des nuages, en est-il de même pour les particules (Vaïtilingom et al. 2012)? Peut-on relier ces tests à certaines espèces caractérisées chimiquement et/ou à des sources spécifiques de PM (Particulate Matter) ? Ce sont des questions préalables au développement d’une évaluation systématique des effets sanitaires des polluants atmosphériques, qui sont l’objet de programmes de recherche très actifs dans de nombreux groupes internationaux, mais encore très peu abordés en France. Elles doivent être prises en compte avant que ne soit développées des campagnes à grande échelle (risque sanitaire, épidémiologie...) qui pourront être mises en oeuvre en partenariat avec les réseaux de mesure de la qualité de l’air dans les années à venir (Kelly and Fussell 2012).Ce projet de thèse vise à mettre en place de nouveaux outils caractérisant la qualité de l’air et son impact biologique, avec les objectifs suivants :-Optimiser et valider un test d’évaluation du potentiel oxydant des aérosols suivant différents types de mélanges ;-Relier ces « proxy » de l’impact sanitaire à la chimie des particules et à la part attribuable des PM selon leurs sourcesIn vitro studies have shown that the health effects of airborne particles (aerosols) are mainly attributed to their inflammatory potential due to the oxidative species they carry on: mostly metals and organic molecules. Diseases triggered then, regionally differ depending on the specific mixtures of different sources of pollution, duration of exposure and susceptibility of individuals. Key parameters to investigate are the bioaccessibility (reactive fraction of the aerosol) and the PM (Particulate matter) oxidative potential to predict aerosol toxicity. To this end, non-invasive tests, that is to say made on the mixture of pollutants itself and not on human or cells, have recently been developed (Cho et al 2005, Sauvain et al 2009, Denys et al 2009, Li et al 2003, Uzu et al 2011). Can we use them evenly, since the chemical composition of aerosols differs drastically between regional areas? We know that such bacteria present in the air are able to lower the oxidative capacity of clouds. Is it the same for particles (Vaïtilingom et al. 2012)? Can we connect these tests to some species or specific sources of identified PM? These preliminary questions need to be addressed before developing a systematic assessment of health effects of air pollutants, which are the subject of very active research programs in many international groups, but poorly discussed in France. They must be taken into account before being developed for large-scale campaigns (health risk, epidemiology...) that can be implemented in partnership with the networks of air quality measurment in the coming years (Kelly and Fussell 2012).This PhD project aims to develop new tools characterizing the air quality and its biological impact, with the following objectives:- Optimize and validate a test evaluation of oxidative potential of aerosols following different types of mixtures;- Connect the "proxy" of the health impact of chemicals and particles attributable PM according to their origin
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Cachon, Fresnel Boris A. "Étude de pollution atmosphérique en Afrique Sub-Saharienne : Cas de Cotonou (Bénin) : Caractérisation physicochimique des matières particulaires d'origine urbaine et impact toxicologique sur des cellules épithéliales bronchiques humaines (BEAS-2B) cultivées in vitro." Thesis, Littoral, 2013. http://www.theses.fr/2013DUNK0348/document.
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La pollution de l'environnement, et particulièrement la pollution atmosphérique et son possible impact sur la santé humaine, suscite un intérêt grandissant dans les pays en voie de développement. Ce travail de thèse s'inscrit dans cette thématique et constitue une étude pionnière en Afrique, et au Bénin plus particulièrement. Nos résultats ont montré que l'essence utilisée à Cotonou était de piètre qualité, caractérisée par l'absence d'additifs et par une forte concentration en benzène, et pouvait être à l'origine de la dégradation de la qualité de l'air de la ville. De même, l'analyse d'échantillons de particules (PM₂․₅ et PM>₂․₅) prélevés dans le quartier de St Michel à Cotonou, a mis en exergue un taux anormalement élevé de particules en suspension dans l'air. La caractérisation physicochimique de ces particules a montré la présence d'un cocktail de composés chimiques (ions, métaux, COVs, paraffines, HAPs, etc.), en proportion plus élevées dans les particules fines PM₂․₅. L'appareil respiratoire constituant la principale voie d'exposition de l'Homme à ces particules atmosphériques, leur potentiel toxique a été évalué au travers d'une étude in vitro menée sur des cellules épithéliales bronchiques humaines (BEAS-2B). Il a été ainsi démontré les propriétés cytotoxiques des deux échantillons de particules ainsi que leur capacité à induire l'expression génique des enzymes de métabolisation des composés organiques et à générer un stress oxydatif. Le déclenchement du processus inflammatoire via l'induction de l'expression génique et la sécrétion protéique de cytokines et l'apparition de modifications dans la voie de l'acide arachidonique (leucotriènes, prostaglandine, thromboxane) ont été notés. Enfin l'approche comparative des PM₂․₅ prélevées au niveau de trois villes d'Afrique de l'Ouest a permis de mettre en évidence des caractéristiques proches au Bénin, en Côte d'Ivoire et au Sénégal et la contribution des émissions du trafic routier dans la pollution de l'airAir pollution and its adverse health effects have shown a growing interest in developing countries. This study deals with this subject and is one of the first conducted in African countries, particularly in Benin. Our results showed that the quality of gasoline used in cotonou was poor, characterized by the absence of additive and a high concentration of benzene. Thus, it could be responsible for the degradation of the city air quality. Therefore, particulate matter samples (PM₂․₅ and PM>₂․₅) were collected in St Michel neighborhood at Cotonou and results showed very high levels of particles in the ambient air. Physicochemical characterization of these particles revealed a presence of various chemicals compounds (ions, metals, VOCs, paraffins, PAHs, ect.) in higher proportion in PM₂․₅ than PM>₂․₅. The respiratory system, the main way of exposure to these airborne particles, was investigated through an in vitro study assessing the toxic potential of PM on human bronchial epithelial cells (BEAS-2B). It has been demonstrated that the two types of particules have cytotoxic properties and ability to induce gene expression of organic compounds metabolizing enzymes and to generate oxidative stress. These particles have triggered the inflammatory process through the induction of gene expression and protein secretion of cytokines, and changes in the arachidonic acid pathway (leukotrienes, prostaglandin, and thromboxane). Finally, comparative approach for PM₂․₅ sampled in three West African cities highlighted the closeness of particles characteristics in Benin, Côte d'Ivoire and Senegal, and a significant contribution of road traffic emissions in the air pollution
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Thelin, Peter. "Design and Evaluation of a Compact 15 kW PM Integral Motor." Doctoral thesis, KTH, Electrical Systems, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3322.
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This thesis deals with the integral motor of tomorrow, and particularly with a variable speed, sensorless permanent magnet synchronous motor with an integrated converter. The rated power is 15 kW at 1500 r/min. The outer dimensions are approximately the same as for the equivalent standard induction motor.
Control strategies for pumps and fans, i.e. suitable loads for variable speed motors, are briefly described. The huge energy savings that can be made by reducing the speed instead of throttling/choking the flow are pointed out. Compared to installing an induction motor with a separate converter, a PM integral motor will probably pay-off in less than a year.
A totally analytical expression for calculating the airgap flux density of permanent magnet motors with buried magnets is derived. The analytical expression includes axial leakage, and iron saturation of the most narrow part of the magnetic circuit of the machine.
A computer program for optimization of PM motors with buried magnets has been developed. It was used to design the manufactured prototype PM integral motor, and the parameters are investigated with analytical and/or FEM calculations. The optimization program is also used to suggest nearoptimum pole numbers for desired powers (4-37 kW) and speeds (750- 3000 r/min) of inverter-fed PM motors. Results show that compact buried PM motors should have relatively large airgaps and high NdFeB-magnet masses to improve the efficiency. Ferrite magnets are unsuitable.
Measurements on the manufactured PM motor, the novel concept of stator integrated filter coils, and the complete PM integral motor are presented. Special attention was given to temperature and overall efficiency measurements.
The rotor cage losses were investigated by time-stepping FEM. Four short circuit fault conditions were also examined in order to evaluate the risks of demagnetization of the buried magnets.
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Söderlund, Erika. "Underhållsplan för maskinhallarna PM 51, 52 och 53 på Bravikens pappersbruk." Thesis, Linköping University, Department of Science and Technology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2902.
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I det här arbetet har jag gjort en del av en underhållsplan för maskinhallarna PM 51, PM 52 och PM 53 på Bravikens pappersbruk för en ettårs-, femårs- och tioårsperiod. I underhållsplanen har jag tagit fram var skadan är, vad som är skadat, placeringen, omfattningen av skadan, åtgärderna och kostnadsförslag från NCC och Ivarsson&Brink Byggnads AB. Jag fick även möjligheten att studera Bravikens asfaltering och göra en preliminär underhållsplan för den. Tyvärr fanns inte tid att utarbeta den så den finns endast som en bilaga, se bilaga 3. Underhållsplanen för asfalteringen gjorde jag tillsammans med Peter Winterquist från Skanska Väg.
För att ta fram dessa data har jag intervjuat sektionscheferna för varje maskinhall eftersom de har ansvaret för fastighetsunderhållet. Jag har även diskuterat med min handledare Anneli Gehlin som är gruppchef för avdelningen bygg och miljö. Fängelset Hall i Södertälje har en mycket utarbetad underhållsplan. Därför gjorde Anneli Gehlin och jag ett studiebesök där för att eventuellt få lite tips och information. Jag har även granskat hur andra industrier har utformat sina underhållsplaner för industrifastigheterna.
En underhållsplan bör alltid hållas aktuell och måste därför uppdateras kontinuerligt. För att kunna göra en mer utarbetad underhållsplan för maskinhallarna på Bravikens pappersbruk behövs det mera tid. Det är mest problem med golven eftersom de är tungt belastade, de har en felaktig beläggning eller är dåligt underhållna. Dessutom täpps dräneringen på taken igen fort. Ett förslag vore att någon kontrollerar golven på varje plan i varje byggnad samt dräneringen på alla tak kontinuerligt eftersom det är mest problem där. Men även hela byggnaderna måste ses över med jämna mellanrum för att kunna hålla underhållsplanen aktuell. Det som ska kontrolleras är golv, dilatationsfogar, fundament, pelare, väggar, dörrar, fönster, tak och fasader.
För att få ett bra underhåll på fastigheterna på Bravikens pappersbruk måste den här underhållsplanen utarbetas mer. Underhållsplanen bör också vara kopplad till en databas för att lättare få information om byggnaden, lättare att bearbeta underhållsplanen samt att underhållskostnaderna kan hållas nere men även för uppföljning av fastigheternas status och kostnader.
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Wenell, Olov. "PM för avhandling om arbetaremigrationen från Sverige till Sovjetunionen 1917-1939." Thesis, Växjö University, School of Humanities, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-6868.
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Title: Memorandum for thesis about the labour migration to the Soviet union 1917-1939
This memorandum for thesis deals with the international migration to the USSR, principally during the 1920s and 1930s and, though the whole process is described, the Swedish emigrants and Soviet Karelia are subjected to a more attentive exposition. The aim has been to present and evaluate previous research on the migration to USSR and Soviet Karelia to find shortcomings, which can function as a point of departure for further studies. Previous research finds that the migration to the USSR was special, due to the strong political awareness of a not insignificant part of the migrants. Furthermore, an important part of the memorandum, partly as a consequence due to the lack of theoretical perspectives in previous research, was to present a theoretical framework for a feasible thesis. The theoretical approaches to class, gender, ethnicity and generation has consistently been connected to previous research to demonstrate how further studies can be constructed. However, the choice of these theoretical approaches also finds its foundation in the inherent advantages for study of social relations, the capability to categorize people, the inherent relation of power, and the connection to a person’s identity. As a result, I claim that the use of the concepts class, gender, ethnicity, and generation can create a bigger understanding of the migration process, about the migrants in both their countries of departure and the daily life of the migrants in their new home country.
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Langner, Marcel. "Exponierter innerstädtischer Spitzahorn (Acer platanoides) - eine effiziente Senke für PM 10?" Karlsruhe Inst. für Geographie und Geoökologie, 2006. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=014865963&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Butler, André J. "Temporal and spatial analysis of PM₂₅ mass and composition in Atlanta." Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/24143.
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Dajaku, Gurakuq [Verfasser]. "Electromagnetic and Thermal Modeling of Highly Utilized PM Machines / Gurakuq Dajaku." Aachen : Shaker, 2006. http://d-nb.info/1170536409/34.
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Asavavisithchai, Seksak. "Improving the stability of Al foams made via a PM route." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417431.
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Yang, Yang. "Harmonic Losses in Windings of Inverter-Fed High-Speed PM Motors." Thesis, KTH, Elektrisk energiomvandling, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-179193.
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This master thesis focuses on the estimation of losses in windings of a high-speed PermanentMagnet (PM) motor. The PM motor studied in this thesis is applied to a nut-runner systemwith specic characteristics such as operating at a high speed (30000 rpm), relatively smallsize and being slot-less. Previously published analytical models for calculation the losses inwindings are discussed in the literature study along with related background theory. Finiteelement method (FEM) 2D is applied in the simulations using FLUX v12. Simulations beginwith several conductors and bundles. Meanwhile, the analytical estimation of those caseswas carried out. The comparisons between results from both sources are discussed. Beforefurther investigations, the way of connection of bundles and conductors and the applicationof symmetrical conditions for following simulations are discussed. Furthermore, the wholewindings with a iron ring and the rotor are simulated step by step in FLUX. Eect of ironmaterial, lamination thickness and base value are investigated. Finally, losses in windingswith various situations are calculated and compared at 10 kHz and 20 kHz.Detta examensarbete behandlar uppskattning av forluster i lindningarna hos en permanentmagnet(PM) hoghastighets-motor. PM-motorn som studerats i denna avhandling tillhor ettmutterdragarsystem avsett for industriellt bruk. Utmarkande egenskaper for denna ar hoghastighet (30000 rpm), relativt liten storlek och avsaknad av statorspar. Tidigare publiceradeanalysmodeller for forlustberakningar i lindningar diskuteras i litteraturstudien tillsammansmed tillhorande bakgrundsteori. Finita Element Metoden (FEM) 2D anvands i simuleringarna.FEM-studierna har utforts i FLUX v12. Studierna utfors initialt pa era ledareoch buntar parallellt med analytiska uppskattningar for dessa. Resultaten fran bada kallornajamfors och diskuteras. Vidare diskuteras olika mojligheter till anslutning av era ledare ochledarvarv, samt tillampning av symmetriska villkor for vidare simuleringar. Lindningarnasimuleras darefter stegvis tillsammans med en jarnring och rotor. Paverkan av jarnmaterial,laminat-tjocklek och basvarde utreds. Slutligen utfors forlustjamforelser i lindningarna forolika kongurationer vid 10 kHz och 20 kHz.
Buntade, ledare, FEM 2D, forluster, PM motor, yteekt och narhetseekt, vridna, lindningarna