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Osman, Ammar. "Low-complexity OFDM transceiver design for UMTS-LTE." Thesis, Blekinge Tekniska Högskola, Avdelningen för signalbehandling, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3716.
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Over the past two decades the mobile wireless communication systems has been growing fast and continuously. Therefore, the standardization bodies together with wireless researchers and mobile operators around the globe have been constantly working on new technical specifications in order to meet the demand for this rapid growth. The 3rd Generation Partnership Project (3GPP) one of the largest of such standardization bodies, works on developing the current third generation (3G) mobile telecommunication systems towards the future 4th generation. Research towards meeting the higher demands for higher data rates was the main reason for the birth of an evolution technology towards the 4th generation mobile systems. This evolution to the current 3rd generation UMTS systems was given the name E-UTRA/UTRAN Long Term Evolution (LTE) by the 3GPP. This thesis research has been carried out at the Telecommunications Research Center (ftw.) in Vienna. It was conducted in the framework of the C10 project “Wireless Evolution Beyond 3G”. One of the fields of research within this project is to have a special focus on the OFDM modulation schemes that are discussed under the new evolution technology (LTE) of the UMTS mobile networks. Therefore, this thesis focuses mainly in analyzing the new requirements, and evaluating them by designing a low-complexity UMTS-LTE OFDM based transceiver. This thesis aims mainly in studying the feasibility of this technology by means of simulation.Tel: +46-704469795 Email: osman@ftw.at,amos04@student.bth.se, ammarmao@gmail.com
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Oliver, Gil José Salvador. "On the design of fast and efficient wavelet image coders with reduced memory usage." Doctoral thesis, Universitat Politècnica de València, 2008. http://hdl.handle.net/10251/1826.
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Image compression is of great importance in multimedia systems and
applications because it drastically reduces bandwidth requirements for
transmission and memory requirements for storage. Although earlier
standards for image compression were based on the Discrete Cosine
Transform (DCT), a recently developed mathematical technique, called
Discrete Wavelet Transform (DWT), has been found to be more efficient
for image coding.
Despite improvements in compression efficiency, wavelet image coders
significantly increase memory usage and complexity when compared with
DCT-based coders. A major reason for the high memory requirements is
that the usual algorithm to compute the wavelet transform requires the
entire image to be in memory. Although some proposals reduce the memory
usage, they present problems that hinder their implementation. In
addition, some wavelet image coders, like SPIHT (which has become a
benchmark for wavelet coding), always need to hold the entire image in
memory.
Regarding the complexity of the coders, SPIHT can be considered quite
complex because it performs bit-plane coding with multiple image scans.
The wavelet-based JPEG 2000 standard is still more complex because it
improves coding efficiency through time-consuming methods, such as an
iterative optimization algorithm based on the Lagrange multiplier
method, and high-order context modeling.
In this thesis, we aim to reduce memory usage and complexity in
wavelet-based image coding, while preserving compression efficiency. To
this end, a run-length encoder and a tree-based wavelet encoder are
proposed. In addition, a new algorithm to efficiently compute the
wavelet transform is presented. This algorithm achieves low memory
consumption using line-by-line processing, and it employs recursion to
automatically place the order in which the wavelet transform is
computed, solving some synchronization problems that have not been
tackled by previous proposals. The proposed encodeOliver Gil, JS. (2006). On the design of fast and efficient wavelet image coders with reduced memory usage [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1826
Palancia
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Johansson, Mattias, and Jonas Ehrs. "Low-Power Low-Noise IQ Modulator Designs in 90nm CMOS for GSM/EDGE/WCDMA/LTE." Thesis, Linköping University, Department of Electrical Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-54552.
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The current consumption of the IQ modulator is a significant part of the totalcurrent consumption of a mobile transmitter platform and reducing it is of greatinterest. Also, as the WCDMA/LTE standards specifies full duplex transmissionsand Tx and Rx are most often using the same antenna, it is crucial to have asolution with low noise generation. Two new proposals have been studied with theaim to reduce the current consumption and noise contribution of the IQ modulator.
A current mode envelope tracking IQM is the first of the studied designs. Thisimplementation lowers the bias currents in the circuit in relation to the amplitudeof the baseband input signals, meaning that a low input amplitude results in alowering of the current consumption. It proves to be very efficient for basebandsignals with a high peak-to-average ratio. Simulations and calculations have shownthat an average current reduction of 56 % can be achieved for an arbitrary LTEbaseband signal.
The second is an entirely new passive mixer design where the baseband voltagesare sequentially copied to the RF node, removing the need for V-to-I conversion inthe mixer which reduces current consumption and noise. Results from simulationshas proven that this design is fully capable of improving both current consumptionas well as the noise levels. With an output power of 4.0 dBm, the power consumptionwas 43.3 mW, including clock generating circuits. This, combined with thefact that the design is small and simple, means that there is definitely a possibilityto replace the present IQM design with a passive mixer.
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Lime, Hugo. "Cross-subframe channel estimation for low-complexity devices in LTE." Thesis, KTH, Teknisk informationsvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-212066.
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One of the most critical issues of wireless communication systems is the timevaryingand frequency-selective channel. Knowledge about the channel greatlyimproves communication performance. It enables coherent demodulation andmeasurements of Signal to Noise Ratio (SNR) and Channel Quality Indicators(CQI). Theses measurements are used to optimize the transmission schemes dependingon the channel conditions. Therefore, the channel estimation is one ofthe most important feature of modern wireless communication devices. In the3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) system,estimation of the channel is achieved using pilots called Reference Signals (RSs)which are scattered in time and frequency. The full estimation of the channel isdone by filtering and interpolation of the estimated pilots.The 3GPP Release 13 issued in June 2016 defines a new category of UserEquipment (UE) named category M1 (Cat-M1) which should support low SNRscenarios. At such low SNR, legacy channel estimation techniques based on persubframeestimation are not efficient enough. The standard thus enables crosssubframechannel estimation by insuring persistence of the channel conditionsduring a group of subframes.This thesis presents techniques for cross-subframe channel estimation. It showshow algorithms can be devised to obtain improved estimation accuracy comparedto single-subframe channel estimates while being resistant to Doppler effect andclock frequency offset. Three types of algorithms are studied: linear averaging,first-order Infinite Impulse Response (IIR) filters and Finite Impulse Response(FIR) Wiener filters. An analytic study of these algorithms is performed to findoptimal parameters in terms of channel estimation Mean Square Error (MSE).Algorithm validation is done with computer simulations to show that the BitError Rate (BER) performance of low-complexity algorithms (linear averagingand first-order IIR filtering) are very close to optimal Wiener filtering ones andthat they provide significant improvement over single-subframe techniques.En av de viktigaste aspekterna i trådlösa kommunikationssystem är tids- och frekvensvariationernai radiokanalen. Kanalkännedom förbättrar kommunikationsprestandaavsevärt. Det möjliggör koherent demodulering och mätning av signaltill brus-förhållande (SNR) och andra kanalkvalitetsindikatorer (CQI). Dessamätningar används för att optimera sändningsmetoden beroende på kanalförhållandena.Därför är kanalskattning en av de viktigaste delarna i modern trådlöskommunikationsutrustning. I system baserade på 3rd Generation Partnership Project(3GPP) Long Term Evolution (LTE), skattas kanalen med hjälp av så kalladereferenssignaler (RS), som är fördelade i tid och frekvens. Den fulla kanalskattningengörs genom filtrering och interpolering av den RS-baserade skattningen.I 3GPP-standarden Release 13, fastslagen i juni 2016, definieras en ny kategoriav användarutrustning benämnd kategori M1 (Cat-M1), som ska stödja scenarionmed lågt SNR. Vid så låga SNR ger inte standardkanalskattningsmetoder baseradepå skattning per delram (subframe) tillräcklig prestanda. Standarden möjliggördärför kanalskattning över flera delramar, genom att säkerställa att kanalvalen ärkonstanta över en grupp av delramar.Denna avhandling presenterar metoder för kanalskattning baserad på flera delramar.Den visar hur metoder kan utformas för att nå förbättrad skattningsnoggrannhetjämfört med skattning från en ensam delram, även vid Dopplerspridningoch avvikande klockfrekvens. Tre typer av algoritmer studeras: medelvärdesbildning,första ordningens återkopplat filter (IIR-filter) samt FIR Wiener-filter. Enanalytisk studie av dessa algoritmer genomförs för att hitta optimalt parameterval,i termer av medelkvadratfelet (MSE) för skattningsfelet. Validering av algoritmernagörs mha datorsimuleringar, som visar att bitfelshalten för lågkomplexitetsalgoritmerna(medelvärdesbildning och första ordningens IIR-filtrering) är väldigtnära vad som nås med optimal Wienerfiltrering och att de ger betydande vinsterjämfört med tekniker baserade på en ensam delram.
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Roderick, Christopher. "The thermodynamic first law for black holes in low-energy string theory." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23293.
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The prescription of R. M. Wald for determining a thermodynamic first law for stationary, axisymmetric, asymptotically flat black holes in general theories of gravity is applied to the effective Lagrangian for the bosonic sector of low-energy heterotic super-string theory. It is found that the presence of the gauge fields necessitates an alteration of the prescription. Specifically, the Lie derivatives with respect to the Killing vector of the gauge fields are non-vanishing. This introduces new terms which ensure gauge-invariance of the final result in a natural way.
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Baldan, Giancarlo. "Low complexity quantized controllers for LTI systems : peak-to-peak performance guarantees." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/103717.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 139-143).
In this thesis, we propose a novel feedback control scheme for unstable LTI systems performing noise attenuation via a finite-rate digital channel. In the first part of the thesis, we introduce the structure of the control system as well as the encoder and decoder used to transmit the required control signals along the digital channel. The performances of the proposed algorithm are then evaluated by providing explicit bounds on the peak-to-peak noise attenuation, in regards to the induced l[subscript infinity symbol] gain of the closed loop . This result is obtained by constructing a new class of storage functions that can be employed to verify the dissipativity of the closed loop system with respect to a suitable supply rate function. In the second part of the thesis, we examine the trade-off between the closed loop performances and the required rate of the channel. While the digital channel imposes some limitations on the achievable induced l[subscript infinity symbol] gain, we show how the performances of the proposed scheme can still approximate those achievable without communication constraints provided that the rate of the channel is large enough. A numerical optimization problem is then devised to design the parameters of the control scheme in order to minimize the strain on the channel while matching some prescribed constraints on the closed loop induced l[subscript infinity symbol] gain.
by Giancarlo Baldan.
Ph. D.
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Niven, Douglas R. "The Wiedemann-Franz law in interacting disordered electronic conductors at low temperatures." Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403600.
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Molinaro, Laura A. "Examination of Contributory Factors to the Low Representation of Women in Law Enforcement." Thesis, Northcentral University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3573278.
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Since the passage of the Equal Employment Opportunity Act of 1972, which amended the Civil Rights Act of 1964, female law enforcement officers have battled obstacles and barriers, both external and internal in their effort to gain equality and assimilate into the role of police officer. The problem examined in this qualitative study was the low percentage of women in sworn law enforcement positions of all ranks. Thirty-six sworn female officers currently serving in the state of Arizona were selected to participate in focus group discussions to assist in the phenomenological examination of low representation of women in law enforcement. The female officers were asked a series of questions to facilitate discussion in an effort to explore their experiences and possibly reveal underlying police cultural factors that may lead to limited opportunities for women who choose law enforcement as a career. The qualitative design fostered a sharing of the stories of these female officers and provided an in-depth understanding of their experiences both on and off the job related to their choice of career. Information-rich data provided by the participants served to inform the Arizona law enforcement community concerning the experiences and career choices of women in law enforcement. Discovered through focus group discussions were the reasons women choose law enforcement as a career as well as why they remain in the profession. The excitement of the job coupled with job security, and salary factored into the decision making processes. Data addressing promotion, leadership, and role models were also revealed with female officers advising an inequitable promotional process, yet one in which they believed women needed to participate to improve the profession for others. Recommendations of formal mentoring and succession planning were made along with changes in the recruitment process. Future study should include male participants as well as female participants. Funding sources or sponsoring organizations should be explored in an effort to expand the scope of future study. Conducting focus groups discussions in different parts of the state and for longer periods of time would permit individuals from different areas of the state an opportunity to participate.
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Gao, Xudong [Verfasser], and Karin [Akademischer Betreuer] Lind. "Low-mass Stellar Evolution Traced with Non-LTE Abundances / Xudong Gao ; Betreuer: Karin Lind." Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://d-nb.info/120588386X/34.
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Newman, Christopher J. "Optimal pathways for low-level public order law : cross-jurisdictional perspectives and comparative standardizations." Thesis, University of Sunderland, 2011. http://sure.sunderland.ac.uk/3792/.
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This thesis explores the boundaries of low-level public order law, drawing on optimal pathways and standardizations across the four legal systems of England and Wales, Australia, The United States of America and Germany. The aim is to identify the origins of the public order frameworks, explore limits of proscribed behaviour and to determine whether low-level public order laws satisfy the requirement of certainty within the respective jurisdictions. The requisite mental elements are investigated alongside the range of defences available to those accused of such an offence. In order to fully investigate the unique synergies between protest and low-level public order, the study uses a comparative approach to examine the interaction between the low level provisions and constitutionally guaranteed rights to free expression; including an examination of the conceptual analysis of the wider frameworks within which protest and low-level public order operate. As the source of much contemporary protest, the impact of the War on Terror upon the nexus between public order and protest will also be examined in respect all of the jurisdictions. It is argued that the law relating to low-level public order in all jurisdictions is, to some extent, based around “catch all” provisions that criminalize a broad range of behaviour and also allow the police and the courts a wide range of discretion when dealing with such offences. The various solutions in respect of structure, operation and judicial interpretation of the offences will be examined. This will highlight standardizations and also fundamental disparities between the four jurisdictions. Such a comparative investigation is unique. The study draws upon multiple standardizations to model the lower end of criminality across the four diverse legal systems, providing dynamic areas of contrast through an examination of both civil law and common law solutions to the treatment of low-level disorder. The efficacy of both codified and ad hoc arrangements to regulate disorder while guaranteeing the right to protest are also assessed. The thesis contributes to the understanding of the scope and contours of low-level public order law as well as extrapolating optimal solutions from the findings of this study.
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Viengsakhone, Louangpradith, Yoshitoku Yoshida, Harun-Or-Rashid Md, and Junichi Sakamoto. "Factors Affecting Low Birth Weight at Four Central Hospitals in Vientiane, Lao PDR." Nagoya University School of Medicine, 2010. http://hdl.handle.net/2237/12909.
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Kemp, Nicola. "Mechanisms underlying the induction of long-term depression in the CA1 region of the hippocampus." Thesis, University of Bristol, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300704.
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Gammon, Tammy Lea. "Improved arcing-fault current models for low-voltage power systems (<1kV)." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/15675.
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MacDonald, Kinsey Elizabeth. "Analysis of Frozen Desserts Using Low-Temperature Scanning Electron Microscopy (LT-SEM)." Thesis, Clemson University, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10982077.
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Commercial vanilla ice cream and other frozen desserts from the United States were analyzed for ice crystal length using low-temperature scanning electron microscopy (LT-SEM). Average ice crystal length was determined using multiple micrographs of each sample/product. Out of the products tested, 11 out of 15 samples had an average ice crystal length above the consumer sensory threshold limit of 55 µm. Products containing stabilizers tended to have smaller average ice crystal lengths than products without stabilizers. With a few exceptions, lower fat products tended to have larger ice crystals because there was less fat to stabilize the ice crystals. Four brands of frozen dessert were studied in detail: a super-premium ice cream (Brand P), a regular ice cream (Brand R), a dietary high protein ice cream (Brand D), and a non-dairy coconut-based frozen dessert (Brand ND). All brands were purchased from two separate supermarket supply chains (Store I and Store P) and analyzed for ice crystal size, weight loss/shrinkage, melting rate, texture, and sensory characteristics before and after being heat-shocked (HS). Brand P, R, and ND all had mean ice crystal sizes that were not significantly different when purchased from either Store I and Store P. The mean ice crystal size increased after HS for all brands except Brand ND. Brand D and Brand P had the highest melting rates, while Brand ND had a much lower melting rate than the other brands tested. Brand ND had a slight decrease in the average ice crystal size and had a decrease in peak force/hardness after HS, while all other brands had an increase in average ice crystal size and an increase in peak force/hardness after HS. Significance was determined using α = 0.05 for all sensory data. The iciness attribute was found to be significantly affected by both brand and HS and an increase in ice crystal size corresponded with an increase in iciness for most samples. The use of stabilizers and emulsifiers in the brands affected various melting characteristics. Additional research is needed on non-dairy frozen desserts and how their physical and sensorial properties are affected by heat-shock.
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Magasiner, Vivien Adele. "The development of posture in very low birthweight infants (<1500 grams)." Master's thesis, University of Cape Town, 1993. http://hdl.handle.net/11427/26598.
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The aims of the study were to examine postural development in very low birthweight and normal birthweight infants and to determine whether deviant postures were predictive of adverse neurodevelopmental outcome. In the first part of the study the 7 postural responses selected by Vojta to evaluate neuromotor development were applied to 69 very low birthweight (VLBW < 1 500 grams) infants and to 28 healthy full-term infants of normal birthweight (> 2500 grams). Of the 69 VLBW infants, 43 were small for gestational age and 26 appropriate for gestational age. All infants were examined at term and 4 months corrected age. They were all later assessed on the Griffiths Mental Development Scale at 12 and 18 months corrected age. There were significant differences in postural reactions between the 2 groups which confirmed the lower tone and greater extension previously described in VLBW infants. An important finding in the study was that poor head and trunk righting noted at 4 months corrected age in VLBW infants, was associated with less developed locomotion at 12 and 18 months as assessed by the Griffiths Mental Development Scale. Thus, a delay in maturation in VLBW infants which was apparent from the assessment of postural responses was still identifiable on the locomotor sub-scales at 12 and 18 months. Five of Vojta's responses were shown to be useful as part of the neurological assessment of high risk infants. In the second part of the study, the 5 useful Vojta responses were incorporated into the Infant Neurodevelopmental Assessment (INA) which was used to assess 76 high risk VLBW infants. The 76 infants consisted of 34 infants with intracranial lesions on ultrasound and 42 without intracranial lesions. All infants were assessed at term and 4 % months corrected age using the INA. At 12 months corrected age they were all assessed on the Griffiths Mental Development Scale. Six infants were diagnosed as having cerebral palsy, all of whom had intracranial lesions. Several clinical signs indicative of cerebral palsy were significant at 4 % months corrected age and will be useful in future studies to diagnose cerebral palsy early. The association between lack of head and trunk control at 4 % months corrected age and a lower locomotor score at 12 months corrected age proved to be significant again and reinforces the finding that early delay in maturation is identifiable on the locomotor scale at 12 months corrected age.
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Ogundipe, Enitan Modupe. "The two year outcome of a regional cohort of low birthweight (LBW) infants in South East England." Thesis, King's College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270948.
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Lee, Chi-ming Leo. "A study on protections of minority shareholders' interest in Hong Kong /." [Hong Kong : University of Hong Kong], 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13498496.
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Hibelot, Catherine. "Etude comparative de deux traitements substitutifs de l'hypothyroidie LT3 et LT4 : répercussions osseuses au bout de un an." Bordeaux 2, 1992. http://www.theses.fr/1992BOR2M032.
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Cross, Richard Barrie Michael. "Low temperature (<150°C) hydrogenated amorphous silicongrown by PECVD with source gas heating." Thesis, De Montfort University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502097.
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Low temperature « 150°C) hydrogenated amorphous silicon grown by PECVD with source gas heating Richard Barrie Michael Cross Hydrogenated amorphous silicon (a-Si:H) is a semiconductor that is widely used in a variety of applications. A particularly important development has been the incorporation of this material into thin film transistor (TFT) arrays for the active matrix addressing of liquid crystal displays. Plasma Enhanced Chemical Vapour Deposition (PECVD) is one of the most successful techniques currently in use for the deposition of device quality a-Si:H. However, there is an increasing desire to improve process compatibility with low cost, plastic substrates. This entails trying to reduce the deposition temperature from approximately 250 - 300°C to below 150 °C, whilst maintaining material quality. This thesis describes the design of a novel, low temperature PECVD system incorporating the facility to pre-heat the deposition source gases. The physical and electronic properties of a-Si:H deposited at <150°C are investigated, and the performance of TFT structures incorporating optimised material as the active layer is described. It is shown that the physical properties of a-Si:H produced at a substrate temperature of 125°C with the source gas line heated to 400 °C are commensurate with films deposited at 250-300 °C. The hydrogen content of the optimised film was found to be 10.5 %, with a Tauc bandgap of 1.66 eV. Pre-heating of the source gases also leads to an increase in the proportion ofhydrogen bonded in the monohydride configuration. It is suggested that the diffusion of the film-forming gaseous species is enhanced by this technique, resulting in a reduction in the degree of disorder within the film and hydrogen elimination. Consequently, the concentration of hydrogen and the Tauc bandgap also decrease, leading to an increase in photoconductivity of one order of magnitude. TFTs exhibit a switching ratio of 105 , which is approximately an order of magnitude smaller than high temperature a-Si:H TFTs, but a comparable OFF current of approximately 10.12A. However, the field effect mobility of these devices is very poor (10.3 cm2V·1s·I). This is thought to be due to a high interface state density at the boundary between the low temperature, gas-heated a-Si:H layer and the high temperature silicon nitride gate insulator.
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Queguiner, Emeline. "Analysis of the data of the EDELWEISS-LT experiment searching for low-mass WIMP." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1196/document.
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De nombreuses observations astrophysiques et cosmologiques tendent à prouver que la matière ordinaire (dite baryonique) ne constituerait qu'environ 5 % du contenu énergétique de l'Univers. Les principales composantes de celui-ci seraient l'énergie noire (à 70 %) ainsi que la matière noire (à 25 %). Cette dernière serait invisible et seuls ses effets gravitationnels traduiraient sa présence dans l'Univers. Plusieurs particules, regroupées sous le terme générique de WIMP (Weakly Interacting Massive Particles), pourraient correspondre à cette théorie et sont activement recherchées. Plusieurs dispositifs expérimentaux ont été développés dans ce but et s'appuyent sur les stratégies suivantes : la production de ces particules au sein de collisionneurs, l'observation de particules produites via l'annihilation de WIMP ou encore la détection directe de ces particules via leur interaction avec le noyau des atomes constitutifs d'un détecteur. C'est sur cette dernière méthode que s'appuie l'expérience EDELWEISS. Il s'agit d'une expérience de détection directe de matière noire dédiée à la recherche de WIMP de masse comprise entre 1 GeV et 1 TeV. Son but premier est de détecter les reculs nucléaires induits par la diffusion élastique de particule de matière noire dans les détecteurs. Les taux d'événements attendus < 10 /(kg.an) étant de plusieurs ordres de grandeur inférieurs à ceux induits par la radioactivité ambiante, une double mesure de l'ionisation et de la chaleur est employée pour discriminer les reculs électroniques induits par les bruits de fonds β et γ des reculs nucléaires induits par les WIMPs. De plus, l'expérience a été placée en site souterrain pour se prémunir des rayonnements cosmiques, induisant des événements dans les détecteurs. Ceux utilisés par l'expérience sont des bolomètres en germanium, appelés FID, refroidis à des températures cryogéniques (18 mK) et opérant à bas champ (1 V/cm). Depuis 2015, la nouvelle stratégie de l'expérience consiste à se focaliser sur les WIMPs de masse inférieure à 10 GeV, zone de recherche privilégiée pour les expériences utilisant des détecteurs cryogéniques. Le fonctionnement de l'expérience a donc été amélioré afin d'atteindre cet objectif.Le but de cette thèse consiste à analyser les campagnes de données de l'expérience, effectuées en 2015 et 2016. Celles-ci utilisaient les détecteurs FID soumis à un champ électrique plus important que précédemment afin d'améliorer leur sensibilité. La limite extraite à partir de ces données s'appuie sur la statistique de Poisson et a permis de mettre en évidence que le bruit de fond dominant de l'expérience à basse énergie impacte grandement les résultats. C'est pourquoi une étude de ces événements, appelés heat-only, a été réalisée. Ceux-ci se caractérisent par une élévation de chaleur vue par les senseurs thermiques sans que les électrodes du détecteur ne mesurent d'ionisation en son sein. Une étude de ce bruit de fond a été réalisée et a permis de mettre en évidence la possibilité de modéliser ces événements. Suite à ces résultats, une analyse par maximum de vraisemblance a été construite. Cette méthode d'analyse permet de soustraire de manière statistique les bruits de fond de l'expérience grâce à leurs spectres en énergie différents de ceux attendus pour un signal de matière noire. De cette façon, une limite sur la section efficace des WIMP a été calculée en utilisant pour la première fois des détecteurs FID soumis à des champs électriques supérieurs aux valeurs utilisées jusqu'à présentMany astrophysical and cosmological observations lead to postulate the existence of an unknown matter, called dark matter. Ordinary matter can explain only 5 % of the energy content of the Universe : the main components would be the dark energy (70 %) and dark matter (25 %). This latter is invisible and manifest itself only via its gravitational effects. Several particles, grouped under the generic term of WIMP (Weakly Interacting Massive Particles), could correspond to this theory and are actively searched. Many experiments have been developed for this purpose and are based on three strategies: the production of these particles with colliders, the observation of the particles produced by their annihilation in astrophysical objects or the direct detection of these particles via their interaction with the nucleus of the atoms constituent of a detector. It is on this last method that the EDELWEISS experiment is based. It is a dark matter direct detection experiment dedicated to the search for WIMP with masses between 1 GeV and 1 TeV. Its primary purpose is to detect nuclear recoils induced by elastic scattering of dark matter particles in detectors. Since the expected event rates < 10 /(kg.year) are several orders of magnitude lower than those induced by ambient radioactivity, a double measurement of ionization and heat is used to discriminate electron-induced recoils arising from β and γ interactions from WIMP-induced nuclear recoils. In addition, the experiment was placed underground to guard against cosmic radiation, inducing events in the detectors. These are germanium bolometers, called FID, cooled to cryogenic temperatures (18 mK) and operating at low field (1 V/cm). Since 2015, the new strategy of the experiment consists of focusing on WIMPs with mass below 10 GeV, an interessant research area where experiments using cryogenic detectors can exploit their ability to operate with experimental thresholds well below 1 keV. The operation of the experiment has been improved to achieve this goal. The aim of this thesis is to analyze the data set recorded by EDELWEISS in 2015 and 2016. These used the FID detectors subjected to a greater electric field than previously to improve their sensitivity. It is expected that the limit on the spin-independent WIMP-nucleon crosssection extracted from these data will be greatly impacted by a dominant background, called heat-only events. That is why they are studied in detail in this work. They are characterized by a rise in heat seen by thermal sensors without any ionization signal on the collecting electrodes. This study resulted in to highlight a model for these events that can be used in the WIMP search analyses. Following these results, a maximum likelihood analysis was constructed. This method of analysis makes it possible to statistically subtract the background noise from the experiment by exploiting the difference between the energy spectra of signal and backgrounds. In this way, limits on the spin-independent WIMP-nucleon cross-section are obtained. They will be compared to the results of other experiments
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Gray, Jane Douglas. "Low interfacial tension (< 1mN/m) studies of multiphase fluid behaviour in porous media." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46319.
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France, Grace. "Features of NMDA receptor-dependent LTP and LTD in the CA1 area of P14 and adult rat hippocampal slices." Thesis, University of Bristol, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.681550.
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N_methyl-O-aspartate receptors (NMOARs) play a pivotal role in synaptic plasticity in the CA1 region of the hippocampus and NMOAR abnormalities have been implicated in many neuropathological diseases and pathophysiologies. Whilst some forms of longterm potentiation (LTP) and long-term depression (LTD) have long been known to have an NMOAR dependence, the involvement of specific NMOAR subunits in LTP and LTD, especially under development, is still a controversial topic. The aim of this study was to clarify the role of the different NMOAR subunits in L TP and L TO, and to investigate the change in kinase activity involved in L TP induction during development. Furthermore, the effects of a newly synthesised phenanthrene derivative and NMOAR potentiator UBP709 were examined on synaptic plasticity at the CA3-CA 1 synapse. In two-week-old animals LTP induction (100 pulses, 100 Hz) was shown to be NMOAR dependent; however, no dominance of a single subunit was discovered. In contrast, LTD was also NMOAR dependent but required activation of GluN2B containing NMOARs in P14 rats. Kinase activity, which is involved in high frequency stimulation induced LTP, was demonstrated to change with age. A multi kinase pathway exists in P14 rats, but this is downregulated and LTP induction becomes CaMKl1 dependent in adult rats. A transient potentiation lasting approximately thirty minutes, known as short-term potentiation (STP), precedes L TP and is also NMOAR-dependent. Induction of STP is dependent on GluN2B- and GluN20-containing NMOARs as STP decays faster in the presence of Ro 25-6981, a GluN2B preferring antagonist, or UBP145, a GluN20 preferring antagonist. NVP, a GluN2A preferring antagonist, had no effect on STP. The novel NMOAR allosteric potentiator, UBP709, enhanced LTO induced by LFS (1 Hz, 900 pulses) and permitted induction of L TO using a 10Hz paradigm that did not induce L TO under control conditions in slices from P14 slices. In adult and aged rats L TO is not readily induced by LFS. However, application of UBP709 permitted induction of a robust L TO in slices from both adult and aged rats. This effect was shown to be NMOARdependent and, in adult rats, required activation of the GluN2B subunit. In summary, results have shown that CaMKl1 appears to dominate LTP in adulthood with the exception of PKA that is involved in STP, induction of which is dependent on GluN2B/20 subunits. Induction of L TP does not depend on a particular NMOAR-subunit whereas induction of L TO is strictly GluN2B dependent, irrespective of the developmental stage of the preparation. UBP709 appears to be a useful tool to investigate synaptic plasticity, which might 'prove beneficial for targeted development of GluN2B selective modulators.
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Grübel, Marius [Verfasser]. "Numerical Investigation of Losses in Condensing Low-Pressure Steam Turbine Flows Based on a Second Law Analysis / Marius Grübel." Düren : Shaker, 2021. http://d-nb.info/1240853785/34.
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Postles, Phillip Anthony. "Construction and testing of a low temperature differential Stirling engine for power generation 2." Thesis, University of Canterbury. Electrical and Electronic Engineering, 2015. http://hdl.handle.net/10092/10839.
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This thesis presents the design and construction of a low temperature differential (LTD) Stirling engine for electric power generation. The target energy sources were geothermal, industrial waste heat or solar heated water. These sources would supply a source temperature of around 90 °C. Assuming that the sink is kept at around 20 °C, the engine was designed based on a temperature difference of approximately 70 °C. The initial design and basic structure of the engine was completed in a previous project utilising first order design methods. The goal was to develop a low cost prototype engine capable of producing up to 500W electrical output power. A novel gamma type engine was proposed
utilising a rotary reciprocating displacer and industrial steam piping to form a low cost pressurised chamber. This project concentrated on advancing the design and construction towards completion with particular emphasis on the electrical control, measurement/instrumentation components, and gas flow through the regenerator. At the completion of this project the displacer piston actuation system has been redesigned. In order to achieve the displacer’s specified 2 ㎐ actuation, both the displacer’s structure and the actuation system were altered. The displacer’s aluminium shell and foam centre were removed and replaced with a pine superstructure coated in depron foam, reducing the moment of inertia from 0.4488 ㎏ ∙ ㎡ to 0.0984 ㎏ ∙ ㎡. A secondary motor was added to the actuation system to increase the actuation power. The gearing ratio was also altered from 10:1 to 2:1 to increase the peak displacer speed. The regenerator was designed and built to suit the unusual wedge shape requirements of
the original design. A ribbed structure was conceived to allow fluid flow to be manipulated within separate sections, producing an even pressure drop over varying regenerator lengths. Simulations were run to optimise both the number of sections and the mass of wire wool to be placed in each segment. The final regenerator design has axial ribs placed at radii
of 93, 134, 192, 276 and 392mm, creating four sections. These sections are filled with 0.68, 0.97, 1.40 and 1.90kg of #0 mild steel wire wool.
As Stirling engines are not self-starting the generator was required to be run as a motor when starting the Stirling engine. To achieve bidirectional flow of current within the starter motor/generator control system, a field oriented control (FOC) inverter from Texas Instruments was purchased and set up to run the 1kW, 3 phase, permanent magnet generator in both motor and generation modes. This will allow the Stirling engine to be brought up to speed with the generator operating as a motor and then switch to generation mode when the motoring current falls below a set limit. Both pressure and temperature measurement systems were developed, constructed and tested in order to collect information about the performance of the engine under operation. Three pressure transducer circuits were designed and constructed with measurement ranges of 10 ㎪, ±0.99 ㎪ and ±6.66 ㎪. These circuits were integrated with a PiocLog1012 analog to digital converter and PicoLog recording software. Eight K-type thermocouples were used for temperature recording. These were sampled with a Pico Technology TC-08 temperature thermocouple data logger which in turn was connected, via USB, to a computer running PicoLog Recorder software. Thus far all component testing has been carried out with test rigs that model the relevant parts of the engine. The displacer actuation system and phase angle control of the displacer and power piston has been tested. Temperature and pressure measurement systems have been independently tested. Motor/generator speed control and switching has been simulated and tested. Unfortunately completion of the engine assembly was not achieved within the scope of this project and therefore fully integrated testing of all components was not carried out. Once mechanical assembly is completed fully integrated testing of displacer actuation, piston position, generator speed control and measurement systems can be achieved.
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Bhuiyan, Sharif Mohammad Nur Ullah. "National law in WTO law." Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614865.
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Bukhari, Syed Munawer. "New Perovskite Materials for Sensors and Low Temperature Solid Oxide Fuel Cell (LT-SOFC) Applications." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20206.
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This work involved the development of new perovskite oxides based on SmFeO3 and testing their performances as sensors for reducing gases (H2, CO & CH4) and as anode materials for dry methane oxidation in solid oxide fuel cells. The new perovskite oxide materials with formula Sm0.95Ce0.05Fe1-xMxO3-δ (M= Co, Ni & Cr) were synthesized by a sol gel method using citric acid as a complexing agent. The resulting materials were characterized by using a battery of techniques including XRD, XRF, XPS, SEM and electrochemical methods.
Sensing experiments revealed that both cobalt doped and Cr doped materials can detect H2, CO and CH4 in air at different temperatures including room temperature. The Ni doped materials did not prove good candidates as sensors. However, their reduction treatment studies showed the formation of metallic nanoparticles on the surface which deeply influence their electrical conductivity as well as sensing ability. Consequently, this modification in surface structure and chemical composition enabled them to sense hydrogen gas at 300oC very effectively. The response of sensors based on these reduced materials was measurable and reversible.
Some materials were also selected on the basis of their reduction stability and electrical properties, and their electrochemical performances were evaluated as SOFC anodes under dry methane and dry hydrogen fuels separately. The performance tests as SOFC anode revealed that the best anode material for the oxidation of dry hydrogen fuel is Sm0.95Ce0.05FeO3-δ. Furthermore, Sm0.95Ce0.05FeO3-δ proved to be coke resistant anode under dry methane fuel and exhibited reasonably low charge transfer resistance values at temperatures between 600-700oC. The doping of Co and Ni at the B-site of Sm0.95Ce0.05FeO3-δ found to be very effective in further improving its performance as SOFC anode towards oxidation of dry methane fuel at the lower temperatures.
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Hayes, Lydia. "Between a grammar of discrimination and a grammar of disconnection : equal pay law, sex-based low pay and care work." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601136.
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This socio-legal research considers the issue of women's low pay and the structure of equal pay law. It concerns how the social justice goal of equal pay is translated into enforceable non-discrimination standards in international, European and domestic law. The focus is paid care work as an exemplar of contemporary pay discrimination in Britain. The research takes three approaches. Firstly, to apply Nancy Fraser's social justice schema of recognition, redistribution and representation to the issue of women's low pay. Secondly, to subject the current framework of equal pay law to critique in relation to low-waged work. Thirdly, to interview care workers and analyse their experiential account of pay injustice in a reproductive industry. The research finds that equal pay law does not address injustices of sex-based pay which are particular to low-waged work, and that the experiential account of sex-based pay is discordant with legal conceptions of pay discrimination. It is argued that equal pay law is, in Fraser's terms, ' misframed '. The thesis presents women's lower pay as an injustice interpreted through two distinct 'grammars' ; a legal grammar of discrimination and an experiential grammar of disconnection. Pay discrimination is currently understood as a conditional injustice in which comparative discrimination names the conditions of sex-based pay. Research data suggests that low pay in reproductive industries fragments women's participation as peers within the economy of paid employment. An injustice of disconnection is itself a discrimination of sex-based low pay. The thesis advocates for broadening a vocabulary of discrimination as an endeavour with twin merit. Firstly, it might enable care workers to place their experience of pay injustice on a spectrum of sex-based legal entitlement. Secondly, it would provide a platform for reform of equal pay law, of benefit to a critical mass of women, and in the interests of social justice.
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Scott, Jr Ernest. "FACTORS INFLUENCING USER-LEVEL SUCCESS IN POLICE INFORMATIONSHARING: AN EXAMINATION OF FLORIDA'S FINDER SYSTEM." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3073.
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An important post-9/11 objective has been to connect law enforcement agencies so they can share information that is routinely collected by police. This low-level information, gathered from sources such as traffic tickets, calls for service, incident reports and field contacts, is not widely shared but might account for as much as 97% of the data held in police records systems. U.S. policy and law assume that access to this information advances crime control and counterterrorism efforts. The scarcity of functioning systems has limited research opportunities to test this assumption or offer guidance to police leaders considering investments in information sharing. However, this study had access to FINDER, a Florida system that shares low-level data among 121 police agencies. The user-level value of FINDER was empirically examined using Goodhue's (1995) Task-Technology Fit framework. Objective system data from 1,352 users, user-reported "successes," and a survey of 402 active users helped define parameters of user-level success. Of the users surveyed, 68% reported arrests or case clearances, 71% reported improved performance, and 82% reported improved efficiency attributed to FINDER. Regression models identified system use, task-fit, and user characteristic measures that predicted changes in users' individual performance. A key finding was that FINDER affirmed the importance of sharing low-level police data, and successful outcomes were related to its ease of use and access to user-specified datasets. Also, users employed a variety of information-seeking techniques that were related to their task assignments. Improved understanding of user-defined success and system use techniques can inform the design and functionality of information sharing systems. Further, this study contributes to addressing the critical requirement for developing information sharing system metrics.Ph.D.
Department of Criminal Justice and Legal Studies
Health and Public Affairs
Public Affairs: Ph.D.
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Senden, Linda. "Soft law in European Community law /." Oxford [u.a.] : Hart, 2004. http://www.gbv.de/dms/spk/sbb/recht/toc/384077412.pdf.
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Laurindo, Marja Mangili. "Entre common law e civil law." reponame:Repositório Institucional da UFSC, 2017. https://repositorio.ufsc.br/xmlui/handle/123456789/179920.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Jurídicas, Programa de Pós-Graduação em Direito, Florianópolis, 2017.Made available in DSpace on 2017-10-03T04:21:46Z (GMT). No. of bitstreams: 1 348552.pdf: 14136770 bytes, checksum: 8b8b640521518567f41d5a953f437668 (MD5) Previous issue date: 2017
Esta dissertação objetiva compreender as condições socioeconômicas em que se dão e as implicações das transformações do direito brasileiro no que se refere à adoção de procedimentos comuns à tradição estrangeira da common law. Disso, se obteve que, em um cenário econômico neoliberal de direito flexível, a análise do discurso politizador e moralizante do judiciário coloca à luz uma série de problemas decorrentes de um novo paradigma interpretativo do Direito. Se para o positivismo jurídico a norma é o limite, para o neoconstitucionalismo o limite está no senso moral do julgador. Nesse estado de crescente indeterminação, adotam-se no Brasil instrumentos estrangeiros como os ?precedentes?; além disso, instituições internacionais como o Banco Mundial lançam diretrizes por meio de relatórios como o Doing Business que indicam que, em termos de eficiência, o sistema de common law é superior ao de civil law. Isso, claro, ao mesmo tempo em que vigora, em países como os Estados Unidos, uma teoria herdeira do Realismo Jurídico, a Law and Economics, que defende a união entre direito e economia em um nível nunca visto antes. A liberdade interpretativa permitida por esse conjunto de fatores rompe a ideia da necessidade de um direito rígido, o que será analisado, em termos de implicações, em seu contexto socioeconômico, qual seja o do neoliberalismo.
Abstract : This dissertation aims to understand the socioeconomic conditions in which occur and the implications of the transformations of Brazilian law regarding the adoption of procedures common to the foreign common law tradition. From this, it was obtained that in a neoliberal economic scenario of flexible law, the analysis of the politicizing and moralizing discourse of the judiciary brings to light a series of problems arising from a new interpretative paradigm of Law. If, for legal positivism, the norm is the limit, for neoconstitutionalism the limit lies in the moral sense of the judge. In this state of growing indeterminacy, foreign instruments are adopted in Brazil as the "precedents"; in addition, international institutions such as the World Bank have issued guidelines through reports such as Doing Business which indicate that the common law system is superior to civil law in terms of efficiency. This, of course, at the same time that, in countries such as the United States, an inheritance theory of Legal Realism, Law and Economics, is defending the union between law and economy on a level never seen before. The interpretive freedom allowed by this set of factors breaks the idea of the need for a rigid Law, which will be analyzed, in terms of implications, in its socioeconomic context, namely neoliberalism.
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Guo, Yicheng, David C. Koo, Yu Lu, John C. Forbes, Marc Rafelski, Jonathan R. Trump, Ricardo Amorín, et al. "STELLAR MASS–GAS-PHASE METALLICITY RELATION AT 0.5 ≤ z ≤ 0.7: A POWER LAW WITH INCREASING SCATTER TOWARD THE LOW-MASS REGIME." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621237.
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We present the stellar mass (M-*)-gas-phase metallicity relation (MZR) and its scatter at intermediate redshifts (0.5 <= z <= 0.7) for 1381 field galaxies collected from deep spectroscopic surveys. The star formation rate (SFR) and color at a given M-* of this magnitude-limited (R less than or similar to 24 AB) sample are representative of normal star-forming galaxies. For masses below 10(9) M-circle dot, our sample of 237 galaxies is similar to 10 times larger than those in previous studies beyond the local universe. This huge gain in sample size enables superior constraints on the MZR and its scatter in the low-mass regime. We find a power-law MZR at 10(8) M-circle dot < M-* < 10(11) M-circle dot: 12 + log (O/H) = (5.83 +/- 0.19)+(0.30 +/- 0.02) log (M-*/M-circle dot). At 10(9) M-circle dot < M-* < 10(10.5) M-circle dot, our MZR shows agreement with others measured at similar redshifts in the literature. Our power-law slope is, however, shallower than the extrapolation of the MZRs of others to masses below 10(9) M-circle dot. The SFR dependence of the MZR in our sample is weaker than that found for local galaxies (known as the fundamental metallicity relation). Compared to a variety of theoretical models, the slope of our MZR for low-mass galaxies agrees well with predictions incorporating supernova energy-driven winds. Being robust against currently uncertain metallicity calibrations, the scatter of the MZR serves as a powerful diagnostic of the stochastic history of gas accretion, gas recycling, and star formation of low-mass galaxies. Our major result is that the scatter of our MZR increases as M-* decreases. Our result implies that either the scatter of the baryonic accretion rate (sigma((M) over dot)) or the scatter of the M-*-M-halo relation (sigma(SHMR)) increases as M-* decreases. Moreover, our measure of scatter at z = 0.7 appears consistent with that found for local galaxies. This lack of redshift evolution constrains models of galaxy evolution to have both sigma((M) over dot) and sigma(SHMR) remain unchanged from z = 0.7 to z = 0.
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Nagai, Shuko. "Effects of earlier initiated continuous Kangaroo Mother Care (KMC) for stable low-birth-weight (LBW) infants in a resource-limited setting." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/157857.
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Zhang, Xinge. "Influence of architecture, materials, and processing on low temperature solid oxide fuel cell (LT-SOFC) performance." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/11262.
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The goal of this dissertation is to develop low temperature solid oxide fuel cells (SOFCs) through the understanding of cell material and component fabrication technology. A typical anode supported thin electrolyte cell structure has been adopted, fabricated by wet ceramic processing and co-firing. Sm₀.₂Ce₀.₈O₁.₉ (SDC) electrolyte cells supported by Ni-Y₀.₁₀Zr₀.₈₄O₁₉₂ (YSZ) cermet substrates, with Sm₀.₅Sr₀.₅CoO₃ cathode and Ni-SDC anode, demonstrate a high performance of 0.89 W cm⁻² at 600°C. A designed experiment quantitatively reveals the internal shorting problem due to the mixed ionic and electronic conductivity of the SDC electrolyte. The internal shorting current density of the thin SDC cell reaches 0.85 A cm⁻² at 600°C under open circuit voltage (OCV) conditions, which limits the fuel utilization to less than 65% and electrical efficiency to below 25%. In order to eliminate the internal shorting problem, a unique bi-layered electrolyte structure has been developed by adding a thin zirconia based electrolyte layer as an electronic blocking layer. A YSZ/SDC bi-layered electrolyte cell prepared by wet ceramic processing and co-firing generated 0.34 W cm⁻² peak power density at 650°C, with an open circuit voltage (OCV) of over 1.0V. Further improvement of the cell performance was achieved by using a Sc₀.₂Ce₀.₀₁Zr₀.₇₉O₁.₉ (SSZ)/SDC bi-layered electrolyte. The cell reached 0.50W cm⁻² at 650°C. Electrochemical impedance analysis reveals that the ionic resistance of the bi-layered electrolyte prepared by co-firing is one order of magnitude higher than the theoretical value, indicating that interaction between the two electrolytes during the co-firing is a main limit. In order to eliminate the bi-layered electrolyte interaction, pulsed laser deposition (PLD) technology is applied for the bi-layered electrolyte cell fabrication. The cell fabricated by PLD reaches power densities of 0.95 W cm⁻² at 600°C, and 1.37 W cm⁻² at 650°C with open circuit voltage (OCV) values larger than 1.02 V, the highest performance ever reported in the literature. Nonetheless, the bi-layered electrolyte cells exhibit relatively high degradation rates. A study on the degradation of bi-layered electrolyte cells indicates that the cathode degradation is the main contributor. Therefore, an optimization of cathode compositions and fabrication conditions is important to improve the cell stability.
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Al-Subaihi, Abdulrahman A. I. "International commercial arbitration in Islamic law, Saudi law and the model law." Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497341.
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Neuwirth, Rostam Josef. "International law and the publicprivate law distinction." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30320.
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Traditionally, public international law and private international law were perceived as two different categories of law; the former governing the international relations between states and the latter those between private individuals. Their relation is based upon an evolutionary development from private to public, and from municipal to international, law. In the modern world, this evolution has culminated in a dynamism reflected in numerous interactions between a wide range of different actors. As a result, the former boundaries between the public and private law, as well as the international and municipal law dichotomy, have become blurred. In an emerging global society, these four major categories have entered a dynamic dialogue that equally challenges both legal theory and practice. This dialogue is centred around a functioning global legal framework, in which public international law and private international law can---due to their distinct scopes of application---answer many unanswered questions, providing that they speak with one voice.
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SOUSA, RITA ALEXANDRA BARREIRA DA MOTA DE. "FEMINIST THEORIES OF LAW: WOMEN EMANCIPATING LAW." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=29195@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRONo processo de libertação da mulher questiona-se o potencial emancipador do direito. A crença das feministas liberais na assimilação da mulher pelo direito deu lugar ao desencanto das feministas culturais na igualdade formal e à afirmação da diferença. Com as feministas radicais desenhou-se a crítica ao direito como status quo, que as feministas pós-modernas levaram mais adiante afirmando que o direito é causa e produto da desigualdade e a necessidade de um novo paradigma no direito. Os métodos jurídicos feministas questionam os métodos jurídicos tradicionais herdados da concepção moderna de Estado liberal, e apresentam uma nova perspectiva do direito, capaz de identificar os pontos em que a sua aplicação reforça as assimetrias de poder e de as corrigir. O estudo do crime de violação e do assédio sexual demonstra as diferentes perspectivas que o direito pode assumir na resolução dos problemas que se colocam às mulheres, e como por vezes se dá a absorção das reformas legais e a sua transformação pela ideologia patriarcal.
In women s liberation process, law is questioned in its emancipating potential. Liberal feminism belief in law assimilationism gave rise to cultural feminists disenchantment in formal equality and to difference affirmation. Radical feminists draw critics to law as a status quo, critics post-modern feminists took further stating law as inequality cause and product, and also the need for a new paradigm in law. Feminist juridical methods question the traditional methods inherited form liberal State modern conception, and present a new perspective in law, able to identify and correct law where its application reinforces power asymmetries. Violation and sexual harassment study aims to demonstrate how law can assume different perspectives in solving women s problems and how, sometimes, legal reforms are absorbed and transformed by patriarchal ideology.
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Soleimani, Hossein. "LTE/LTE-Advanced for Vehicular Safety Applications." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/37840.
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IEEE 802.11p, the known standard for Vehicular Adhoc NETworks (VANETs), suffers from scalability issues and unbounded delay. In addition, the desire to use networks already in existence has created motivation for using cellular networks for vehicular applications. LTE-Advanced is one of the most promising access technologies in the wireless field, providing high data rate, low latency, and a large coverage area. Thus, LTE/LTE-A can be potential access technologies for supporting vehicular applications. Vehicular safety applications are based on broadcasting messages to neighboring vehicles. The vehicle location precision is crucial for safety applications. Thus, the freshness of the information (i.e. vehicle location) at the neighboring vehicles is very important. As LTE is an infrastructure-based network, all transmissions should pass through it. When the load of the network is high compared to the available resources, large delays may occur.
The focus of this thesis is to propose solutions to make LTE suitable for vehicular safety applications. The first solution is to adapt the vehicular safety application to be suitable in LTE network. For this purpose, we propose an adaptation of the safety message generation rate. This adaptation uses a queueing model to compute the freshness of the information of vehicles at the destination, based on their message generation rates. It then adjusts the generation periods to provide a similar accuracy for all vehicles. The second approach is to modify the LTE and make it suitable for these kinds of applications. Thus, we proposed a scheduler for LTE which is suitable for vehicular safety applications. It considers the speed and location of the vehicles to allocate the resources to them for the transmission of safety messages. We also studied the message dissemination in the downlink, and proposed an efficient way to deliver the safety messages to the neighboring vehicles. Finally, we propose a scheme that uses both LTE-D2D and LTE-cellular communication for the transmission of safety messages. The centralized location information is used for Device-to-Device (D2D) pair discovery and resource allocation. The proposed scheme provides resource efficiency by enabling the reuse of the resources by vehicles. We also study the effect of the awareness range and period of updating location information at the server on resource usage and accuracy of D2D pair detection.
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Infantino, Marta. "Comparative Law of causation in Tort Law." IUS ET VERITAS, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/123595.
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this article analyzes the causal element of torts from the perspective of comparative law, focusing on the field of tort liability. Thus, it specifies both the particular aspects of the investigation as well as each legal system studied. then, the article discusses the differences and similarities of each system. Later, it stops on the dominant approaches examining its success on facing the tort phenomenon in order to highlight the essential characteristics that determine the various approaches tort liability can assume.El presente artículo analiza el elemento causal de la responsabilidad civil desde una perspectiva de derecho comparado, haciendo énfasis sobre el campo de la responsabilidad aquiliana. Así, precisando tanto los aspectos particulares de la propia investigación como de cada Ordenamiento Jurídico estudiado, el artículo aborda las diferencias y similitudes de cada Ordenamiento. De esta forma, se detiene sobre los enfoques dominantes examinando la capacidad de los mismos. Ello con la finalidad de evidenciar las características esenciales que determinan los diversos alcances que puede asumir la responsabilidad aquiliana.
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Cassam, Yasmin. "The effect of falciparum malaria prevalence on the effectiveness of intermittent preventive treatment with Sulfadoxine-Pyrimethamine during pregnancy in reducing low birth weight in southern Mozambique." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/29732.
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Malaria infection is a major cause of morbidity and mortality in tropical countries, and particularly in Mozambique. Recently substantial resources have been used to reduce the burden of malaria in Mozambique. These include the distribution of insecticide treated bed-nets, indoor residual insecticide spraying, access to artemisinin-based combination treatment (ACT), and intermittent preventive treatment of pregnant women with sulfadoxine-pyrimetamine (SP-IPTp). The most important benefit of SP-IPTp in malaria endemic areas has been the increase in birth weight, thus increasing the probability of child survival. The SP-IPTp policy was based on evidence of its effectiveness in areas of high intensity malaria transmission. The effect of SP-IPTp has been less evident in the presence of high coverage with insecticide treated bed-nets. It is not know whether reducing the risk of malaria through effective vector control using indoor residual insecticide spraying and large-scale deployment of ACTs has a similar effect in reducing the impact of SP-IPTp on birth weight. At the same time, increasing resistance of SP could be compromising the effect of SP-IPTp on birth weight, as could co-infection with HIV. The aim of this study was to determine if the effect of SP-IPTp on reduction in risk of low birth weight is modified by Plasmodium falciparum malaria prevalence. This retrospective antenatal record review, analyzed 20867 antenatal records from 2005 to 2007 from public health facilities in Maputo and Gaza provinces, southern Mozambique. One or two doses of SP-IPTp does not have any effect on reducing the risk of low birth weight, while women who had at least three doses of SP-IPTp had a 15% lower risk of their babies being born with low birth weigh compared with fewer doses, (OR=0.85; 95% CI 0.73 – 1.00; p=0.053). The risk of babies being born with low birth weight was reduced by 28% when both malaria prevalence and dhfr / dhps mutation prevalence are low, (OR=0.72; 95% CI 0.51 – 1.00), but this effect was no longer significant with higher malaria prevalence and or mutation prevalence. SP-IPTp has an effect on reducing low birth weight with three or more doses, and in areas where malaria prevalence and mutation prevalence are low. CopyrightDissertation (MSc)--University of Pretoria, 2013.
Clinical Epidemiology
unrestricted
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Okoro, TASIE B. "THERMAL DEGRADATION OF PC AND PA6 DURING LASER TRANSMISSION WELDING (LTW)." Thesis, 2013. http://hdl.handle.net/1974/8340.
Full textAbstract:
In laser transmission welding (LTW), a laser beam passes through the laser-transparent part and is absorbed by carbon black (CB) in the laser-absorbent part. This causes a temperature rise at the interface between the parts which leads to melting, diffusion and ultimately joining of the two components. Weld temperatures increase with laser power at a given scan speed. However at higher temperatures, it has been observed that weld strength of LTW starts to decline due to material thermal degradation.
Thermal degradation of materials is a kinetic phenomenon which depends on both temperature and time. Therefore there is no specific temperature for thermal degradation. Thermal gravimetric analysis (TGA) is used to study the thermal degradation of two commonly used thermoplastic materials: polycarbonate (PC) and polyamide 6 (PA6). Each material was studied at two levels of CB. It is shown in this work that increasing the carbon black (CB) level from 0.05 to 0.2wt% has no significant effect on the thermal stability of PA6. However, it is observed that increasing the CB level from 0.05 to 0.2wt% has a noticeable effect on the thermal stability of PC.
The TGA data were then used to obtain the kinetic triplets (frequency factor (k_0), activation energy (E), and reaction model (f(α))) of the materials using a non-linear model-fitting method. These kinetic triplets were combined with temperature-time data obtained from a Finite Element Method (FEM) simulation of the LTW process to predict material degradation during LTW. The predicted degradation was then compared with experimental data. It is found that the predicted onset of material degradation is in good agreement with experimentally observed thermal degradation (of both visually observed degradation onset and weld strength decline) for PC and PA6.
A semi-empirical model based on the FEM temperature data is also developed in this work as a simpler alternative for obtaining LTW maximum temperature-time profiles for prediction of material thermal degradation during LTW. Comparison of the predicted material conversion using temperature-time profile obtained by FEM and the semi-empirical model shows good agreement.Thesis (Master, Chemical Engineering) -- Queen's University, 2013-09-27 10:45:24.688
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Mayboudi, LAYLA S. "Heat Transfer Modelling and Thermal Imaging Experiments in Laser Transmission Welding of Thermoplastics." Thesis, 2008. http://hdl.handle.net/1974/1551.
Full textAbstract:
This thesis presents a comprehensive study on the thermal modelling aspects of laser transmission welding of thermoplastics (LTW), a technology for joining of plastic parts. In the LTW technique, a laser beam passes through the laser-transmitting part and is absorbed within a thin layer in the laser-absorbing part. The heat generated at the interface of the two parts melts a thin layer of the plastic and, with applying appropriate clamping pressure, joining occurs. Transient thermal models for the LTW process were developed and solved by the finite element method (FEM). Input to the models included temperature-dependent thermo-physical properties that were adopted from well-known sources, material suppliers, or obtained by conducting experiments. In addition, experimental and theoretical studies were conducted to estimate the optical properties of the materials such as the absorption coefficient of the laser-absorbing part and light scattering by the laser-transmitting part. Lap-joint geometry was modelled for semi crystalline (polyamide - PA6) and amorphous (polycarbonate - PC) materials.
The thermal models addressed the heating and cooling stages in a laser welding process with a stationary and moving laser beam. An automated ANSYS® script and MATLAB® codes made it possible to input a three-dimensional (3D), time-varying volumetric heat-generation term to model the absorption of a moving diode-laser beam. The result was a 3D time-transient, model of the laser transmission welding process implemented in the ANSYS® FEM environment.
In the thermal imaging experiments, a stationary or moving laser beam was located in the proximity of the side surface of the two parts being joined in a lap-joint configuration. The side surface was then observed by the thermal imaging camera. For the case of the stationary beam, the laser was activated for 10 s while operating at a low power setting. For the case of the moving beam, the beam was translated parallel to the surface observed by the camera. The temperature distribution of a lap joint geometry exposed to a stationary and moving diode-laser beam, obtained from 3D thermal modelling was then compared with the thermal imaging observations. The predicted temperature distribution on the surface of the laser-absorbing part observed by the thermal camera agreed within 3C with that of the experimental results. Predicted temperatures on the laser-transmitting part surface were generally higher by 15C to 20C. This was attributed to absorption coefficient being set too high in the model for this part. Thermal imaging of the soot-coated laser-transmitting part surface indicated that significantly more scattering and less absorption takes place in this part than originally assumed. For the moving laser beam, good model match with the experiments (peak temperatures predicted within 1C) was obtained for some of the process conditions modelled for PA6 parts. In addition, a novel methodology was developed to extract the scattered laser beam power distribution from the thermal imaging observations of the moving laser beam.Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2008-10-08 10:39:30.952
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Wang, Weicheng, and 王偉丞. "A Low-Power Low-Voltage PMOS-only VCO and LTE Transmitter Module Design." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/40208208065802559358.
Full textAbstract:
碩士國立中正大學
電機工程研究所
100
A low-voltage and low-power 0.18-μm CMOS voltage-controlled oscillator, using PMOS-only transistor, and LTE transmitter module ware designed in this thesis. On the CMOS VCO,the bulk of the PMOS varactor, which is disconnected with drain and source nodes, is properly biased to lower the operation voltage and power consumption. The measured operating frequency range is from 2344 to 2844 MHz, equivalently 19.2% of the tuning bandwidth. The output power is -2.3 ~ -5.9 dBm, the phase noise is -119.78 ~ -105.3 dBc/Hz , and the power consumption is 2 mW. The figure of merit is -190.8 dBc/Hz. On the LTE transmitter module, an LTE dual-band RF educational transmitter module was designed and implemented in hybrid microwave integrated technology. This transmitter uses dual-conversion heterodyne topology. The link budget was calucalted first. Then the subcircuit were defined, designed, and implemented in the board level. Finally the subcircuits were integrated in a rack such that the circuit order can be changed according to the desired function without redesigning the subcircuits. The CW signal and the digitally-modulated signal test were carried out to validate the design methodology.
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Lin, Haun-Ju, and 林奐竹. "Design of Low-Noise Mixer and Low Voltage Delta-Sigma Modulator for LTE Transmitter." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/7u6ew8.
Full textAbstract:
碩士國立臺北科技大學
電腦與通訊研究所
99
A high linearity, low noise figure of the mixer circuit design is to be proposed in the first part of this paper. Conventional double-balanced Gilbert mixer is used as a design in the main structure of the circuit. Traditional Gilbert mixer conversion gain can be increased, but its power consumption, noise figure and linearity can not be effectively improved. Therefore, this circuit is proposed to increase the linearity and lower noise figure of the conceptual design so as to improve linearity and noise figure of the problem. The proposed mixer was implemented with TSMC 0.18μm 1P6M CMOS process, and the chip area is 1.054 x 0.997 mm2 (with PADs). Low-voltage Class D amplifier circuit is to be proposed in the second part of this paper. Class D amplifier is mainly used in audio systems, so we focus on the noise interference in the signal band. Delta-Sigma modulator is applied in the control circuit techniques, it can be moved the noise to high frequency , and make noise components reduced in the signal bandwidth. We input audio signal to the second order Delta-Sigma modulator, it can make analog audio signal into Pcm. It can control power Mos by buffer circuit and Non-overlapping circuit output. Finally, we can revert audio signal with using low-pass filter. The circuit is used closed-loop structure which can increase the stability of system. The half-bridge output stage and the feedback path can improve total harmonic distortion (THD) and signal-to-noise ratio(SNR). The proposed circuit was implemented with TSMC 0.35μm 2P4M CMOS process, and the chip area is 2.471 x 1.8 mm2 (with PADs).
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Navakkode, Sheeja Gangadharan. "Investigation of cellular mechanisms of hippocampal LTP and LTD /." 2006. http://diglib.uni-magdeburg.de/Dissertationen/2006/shenavakkode.htm.
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Tsao, Wei-Wen, and 曹瑋文. "Low-Complexity Precoding and Antenna Selection of LTE System." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/26803923470686956945.
Full textAbstract:
碩士國立臺灣海洋大學
通訊與導航工程學系
102
Due to the advantages of high data rate and efficacy spectrum utilization, Multiple Input Multiple Output (MIMO) has been widely used in the broadband communication systems. However, as the number of the adopted antennas at both the transmitter and receiver is increasing, the computational complexity will be rapidly increased. To solve this problem, a promising method is to select the best set of antenna among the available ones for transmission. In LTE System, Channel State Information (CSI) can be acquired at the transmitter via three parameter, i.e., Rank Indicator (RI), Precoding Matrix Indicator (PMI) and Channel Quality Indicator (CQI). These parameters can help the transmitter to adjust the signals dynamically to have a better transmission quality. This thesis studies the RI, PMI and Antenna Selection methods and proposes several schemes to have the advantage of low computational complexity. Keyword: Multiple Input Multiple Output system; antenna selection; LTE; Rank Indicator (RI); Precoding Matrix Indicator (PMI);
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Lin, Yi-Hsuan, and 林怡萱. "Dual-Mode Low-Complexity Codebook Searching Algorithm and Architecture Design for LTE/LTE-Advanced Systems." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/58431626006206571087.
Full textAbstract:
碩士國立臺灣大學
電子工程學研究所
100
LTE (Long Term Evolution) and LTE-A (LTE-Advanced) systems are dominant standards in future mobile communication systems. LTE and LTE-A systems utilize multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) technique, which can resist multipath interference and improve the spectrum efficiency. The main concern is the interferences among all transmit and receive antennas. The closed-loop scheme, i.e. precoding, is proved to be about 4dB better performance [28] compared with the open-loop solution, which also reduces the overall power consumption. Codebook is a useful precoding technique for limited feedback systems because only few bits are required to feedback. Several codebook selection criteria for linear receivers have been proposed in [13][14][22]-[24]; nevertheless, these selection criteria are computationally intensive and most of them are not feasible for aperiodic feedback reporting in LTE and LTE-A systems. On account of the limited processing hardware and feedback delay constraints, low-complexity transceivers with efficient codebook selection scheme should be considered. In this thesis, the low-complexity codebook searching engine is proposed for LTE and LTE-A systems. The properties and mutual correlations of the LTE and LTE-A codebooks are analyzed and then a low-complexity grouping FFT-based codebook searching algorithm is proposed. Since the proposed algorithm is an algorithmic transformation, there is no performance loss. The proposed schemes have significant effect of reducing the number of multiplications by 56%, compared with the low-complexity cofactor scheme [26]. At last, a dual-mode low-complexity codebook searching engine with TSMC 90 nm is implemented. The IP size is 2.2 mm2 and the equivalent gate count is 547.6K. The operating frequency is 125MHz.
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Chung-YenLiu and 劉忠艷. "High-Throughput Turbo Decoder Design with Low-Complexity Interleaver for 3GPP-LTE/LTE-A Systems." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/69786469787073718365.
Full textAbstract:
碩士國立成功大學
電機工程學系
102
Turbo codes have been widely adopted by wireless communication standards due to their excellent error correction performance. As the next-generation standard, 3GPP-LTE/LTE-A systems use turbo coding as the channel coding scheme with a higher throughput demand. To meet this higher data rate requirement, the highly-parallel turbo decoder architecture is frequently applied. How to reduce the complexity of parallel interleaver and increase the throughput rate are essential to the turbo decoder design. In this thesis, an efficient architecture of turbo decoder is presented by using two-dimension differential calculation interleaver and dummy calculation-reduced parallel-window algorithm to achieve the throughput demand in 3GPP-LTE/LTE-A systems. The proposed interleaver can support highly parallel soft-input/soft-output (SISO) decoding architecture with low complexity computation. Furthermore, the proposed decoding algorithm can increase the throughput rate without performance degradation by reducing the dummy calculation. Experimental results show that the developed turbo decoder can improve the normalized area efficiency by about 24.53% compared to related works for high-throughput implementation.
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Chang, Hsuan-Jui, and 張軒瑞. "LTE/WWAN Low-profile Planar Antenna for Tablet Communication Device." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/05739210336682972285.
Full textAbstract:
碩士國立中山大學
電機工程學系研究所
101
In this thesis, two low-profile planar LTE/WWAN antennas for tablet communication devices are presented. The first antenna is disposed around a ground corner, and the antenna size is 57.5 x 6.5 x 0.8 mm3 only. By embedding an opening in a loop strip, it can be transformed into a dual-branch monopole antenna. By aided with a matching circuit, the antenna can provide two wide operation bands with a planar, low-profile structure, making it promising for applications in modern slim tablet communication devices with a narrow frame. The proposed antenna applied to form a two-antenna array is also studied. A second low-profile planar antenna to be employed along an edge of the tablet device system ground plane is also presented. The second antenna is also a loop strip having an opening, sized 55 x 10 x 0.8 mm3. In the second structure, the opening and the feeding point of the antenna are arranged to be at the same edge of loop strip, which allows the antenna to have two wide operating bands with a low-profile structure because the proposed structure can decrease the coupling between the antenna and nearby ground plane. Both the two antennas in this thesis can cover the 704~960 and 1710~2690 MHz bands for the LTE/WWAN operation.
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Tseng, Pin-Kai, and 曾斌凱. "A Novel Low Complexity Cell Search Scheme for LTE Systems." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/48373608021548987343.
Full textAbstract:
碩士國立中山大學
通訊工程研究所
97
Cell search of Third Generation Partnership Project Long Term Evolution (3GPP LTE) includes time synchronization and frequency synchronization of frames, and the acquisition of Cell Identity (Cell ID). The LTE systems use 504 Cell IDs divided into 168 unique Cell-Identity Groups (Cell-ID Groups), and each Cell-ID Group comprises three Sector Identities (Sector IDs). After reaching synchronization of time and frequency between frames, the Cell ID acquisition scheme provided by specification of 3GPP LTE is consisted of two steps, the first step must utilize three matched filters to detect one out of three Sector IDs, and then implement coherent correlation detection between 168 Pseudo Random Noise Sequences (PN sequences) to obtain the index of Cell-ID Group. So the cell search scheme provided by LTE standard has to detect correlation of all sequences, and computed complexity brings considerable processing time to effect the delay time of services power on, standby time, energy saved, and cost of manufacture. To reduce complexity, we propose a perfect sequence with special structure as preamble, and the sequence is linear combination of two base sequences. We put the sequences within Primary Synchronization Channel (P-SCH) and Secondary Synchronization Channel (S-SCH), and we utilize the phase rotation factors of the sequences as index to generate Cell ID, instead of the current scheme to generate Cell ID with the indexes between sequences and sequences. Based on the sequences in multipath channel model, simulation results verify the detection probability of Cell IDs by proposed scheme is 100% when SNR is -8dB, and it is 98.7% by the scheme in LTE specification after perfect time and frequency compensation. Except that, Cell ID detection performance is similar without channel compensation to reduce implement complexity. Index Terms- cell search, 3GPP LTE, 16n perfect sequence.
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Yu, Jih-Hua, and 游日華. "A Low Noise Buck Converter for 4G LTE Transmitter Applications." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/4f2uv6.
Full textAbstract:
碩士國立臺北科技大學
電腦與通訊研究所
102
In first part, we proposed a delta-sigma based DC-DC buck converter with peak efficiency of 91.5%. We can effectively lower the harmonic tones of converter’s output owing to the noise-shaping and unfixed switching frequency of delta-sigma. The proposed buck converter has been fabricated with a TSMC 0.35 μm CMOS 2P4M process. We design the sampling frequency with 5.12 MHz, the inductor of 4.7 μH and the capacitor of 4.7 μF. Measured results show that the recovery time is about 60 μs for a load step of 450 mA. The noise level is lower than -70 dBm. The chip area is 1.45 x 1.22 mm2。 In order to improve the controller’s low frequency noise and achieve faster transient response, we proposed a low noise buck converter with chopper-stabilization delta-sigma modulator in second part. By adding chopper switches and fast path which is from circuit’s output to feed to delta-sigma modulator in order to lower low frequency’s noise and accelerate the transient response, respectively. The proposed buck converter has been fabricated with a TSMC 0.35 μm CMOS 2P4M process. We design the sampling frequency with 5.12 MHz, the inductor of 2.2 μH and the capacitor of 4.7 μF. Measured results show that the recovery time is about 20 μs for a load step of 450 mA. Average efficiency is above 85% over its full loading range when input/ output voltage equals to 3.6 V/3 V. The peak efficiency is 90% at load current of 150 mA. The noise level is lower than -76 dBm. The chip area is 1.49 x 1.46 mm2。