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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

PAPR Reduction Schemes Based on Spreading Code Combination and Subcarrier Scrambling for MC-CDMA Systems

Lee, Ming-Kai 23 August 2011 (has links)
In order to improve the drawback of the high peak-to-average power ratio (PAPR) on the multi-carrier systems, in this paper we derive a statistical characterization approach of the time domain signal power variance metric by means of every user¡¦s spreading code combination and subcarrier scrambling. We obviously reduce the PAPR on the multi-carrier code division multiple access (MC-CDMA) systems by resorting the combination of spreading codes and scrambling the polarities of subcarriers. Due to the large calculative number of exhaustive search, we use a low complexity Replacement Search Method (RSM) to reduce the calculation times of searching, and obtain a good result. Moreover, we can get a better PAPR reduction performance by increasing the number of iteration.
102

"I can turn karaoke into open mic night" : an exploration of Asian American men in hip hop

Jackson, Tamela Teara 22 November 2013 (has links)
The purpose of this report is to explore the ways in which Asian American men participate in hip hop culture, and what this participation says about their politics and representation in United States media and popular culture. This is done through an analysis of Freestyle Friday All Star, MC Jin, a Chinese American emcee from Queens, New York, as well as DJ Soko, a Korean American DJ from Detroit, Michigan. I argue that their participation is a desire for political power and creative visibility rendered on their own terms. / text
103

Optimal maintenance of a multi-unit system under dependencies

Sung, Ho-Joon 17 November 2008 (has links)
The availability, or reliability, of an engineering component greatly influences the operational cost and safety characteristics of a modern system over its life-cycle. Until recently, the reliance on past empirical data has been the industry-standard practice to develop maintenance policies that provide the minimum level of system reliability. Because such empirically-derived policies are vulnerable to unforeseen or fast-changing external factors, recent advancements in the study of topic on maintenance, which is known as optimal maintenance problem, has gained considerable interest as a legitimate area of research. An extensive body of applicable work is available, ranging from those concerned with identifying maintenance policies aimed at providing required system availability at minimum possible cost, to topics on imperfect maintenance of multi-unit system under dependencies. Nonetheless, these existing mathematical approaches to solve for optimal maintenance policies must be treated with caution when considered for broader applications, as they are accompanied by specialized treatments to ease the mathematical derivation of unknown functions in both objective function and constraint for a given optimal maintenance problem. These unknown functions are defined as reliability measures in this thesis, and theses measures (e.g., expected number of failures, system renewal cycle, expected system up time, etc.) do not often lend themselves to possess closed-form formulas. It is thus quite common to impose simplifying assumptions on input probability distributions of components' lifetime or repair policies. Simplifying the complex structure of a multi-unit system to a k-out-of-n system by neglecting any sources of dependencies is another commonly practiced technique intended to increase the mathematical tractability of a particular model. This dissertation presents a proposal for an alternative methodology to solve optimal maintenance problems by aiming to achieve the same end-goals as Reliability Centered Maintenance (RCM). RCM was first introduced to the aircraft industry in an attempt to bridge the gap between the empirically-driven and theory-driven approaches to establishing optimal maintenance policies. Under RCM, qualitative processes that enable the prioritizing of functions based on the criticality and influence would be combined with mathematical modeling to obtain the optimal maintenance policies. Where this thesis work deviates from RCM is its proposal to directly apply quantitative processes to model the reliability measures in optimal maintenance problem. First, Monte Carlo (MC) simulation, in conjunction with a pre-determined Design of Experiments (DOE) table, can be used as a numerical means of obtaining the corresponding discrete simulated outcomes of the reliability measures based on the combination of decision variables (e.g., periodic preventive maintenance interval, trigger age for opportunistic maintenance, etc.). These discrete simulation results can then be regressed as Response Surface Equations (RSEs) with respect to the decision variables. Such an approach to represent the reliability measures with continuous surrogate functions (i.e., the RSEs) not only enables the application of the numerical optimization technique to solve for optimal maintenance policies, but also obviates the need to make mathematical assumptions or impose over-simplifications on the structure of a multi-unit system for the sake of mathematical tractability. The applicability of the proposed methodology to a real-world optimal maintenance problem is showcased through its application to a Time Limited Dispatch (TLD) of Full Authority Digital Engine Control (FADEC) system. In broader terms, this proof-of-concept exercise can be described as a constrained optimization problem, whose objective is to identify the optimal system inspection interval that guarantees a certain level of availability for a multi-unit system. A variety of reputable numerical techniques were used to model the problem as accurately as possible, including algorithms for the MC simulation, imperfect maintenance model from quasi renewal processes, repair time simulation, and state transition rules. Variance Reduction Techniques (VRTs) were also used in an effort to enhance MC simulation efficiency. After accurate MC simulation results are obtained, the RSEs are generated based on the goodness-of-fit measure to yield as parsimonious model as possible to construct the optimization problem. Under the assumption of constant failure rate for lifetime distributions, the inspection interval from the proposed methodology was found to be consistent with the one from the common approach used in industry that leverages Continuous Time Markov Chain (CTMC). While the latter does not consider maintenance cost settings, the proposed methodology enables an operator to consider different types of maintenance cost settings, e.g., inspection cost, system corrective maintenance cost, etc., to result in more flexible maintenance policies. When the proposed methodology was applied to the same TLD of FADEC example, but under the more generalized assumption of strictly Increasing Failure Rate (IFR) for lifetime distribution, it was shown to successfully capture component wear-out, as well as the economic dependencies among the system components.
104

Racionais Mc\'s: do denuncismo deslocado à virada crítica (1990-2006) / Racionais Mc´s: from reporting to critical turning (1990-2006)

Charleston Ricardo Simões Lopes 26 June 2015 (has links)
O presente trabalho analisa dois momentos na obra do grupo de rap paulistano Racionais Mc´s. O primeiro momento, de 1990 a 1993, estrutura um modo de crítica que se caracteriza pelo tom denuncista, assemelhado ao tom professoral, no enfoque das composições, cujo ponto de vista dos raps não se constrói a partir da periferia, mas deslocado, pretensamente acima dela, em razão da posição em destaque do rapper nesse espaço social. Já o segundo momento, a partir dos raps Fim de semana no parque e Homem na estrada, do álbum Raio X do Brasil (1993), é marcado pela superação do ponto de vista professoral, pois as composições formalizam a perspectiva do morador de periferia, cujo resultado estético não só olha para a periferia, mas partir desse espaço social. / The present work focus on and analyses two moments in the work of São Paulo rap group Racionais MC\'s. The first of these moments, from 1990 to 1993, structures a critical mode that singularizes itself by an accusatory, rather preachy, tone in the artistic approach developed by the compositions. Its point of view does not builds itself from the peripheral world, but is displaced as if above it, due to the rapper\'s outstanding position in that social space. The second moment, starting with the raps \"Weekend in the park\" (\"Fim de semana no parque\") and \"The man in the road\" (\"Homem na estrada\"), from the Raio X do Brasil album (1993), overcomes that preachy tone, as the aforementioned compositions formalize the peripheral resident\'s perspective, the aesthetic result of which does not only look at the periphery, but from that social space.
105

Evaluation of new laboratory methods for routine use

Lehto, T. (Tiina) 12 January 2016 (has links)
Abstract Laboratory medicine is under constant pressure from changes in the operating environment. Organisational changes and tendering processes have led to a trend towards shorter turn-around times and more cost-effective choices. Analysis tools that were previously only available at research laboratories, such as the mass spectrometer and polymerace chain reaction (PCR), have now made their way to university hospital laboratories and even mid-sized laboratories. Organisational changes have increased the need to monitor the pre-analytical steps. The specimen can be drawn from the patient in a satellite laboratory, which may be located several hours from the central laboratory. The increased transportation times may change the analytical properties of the specimens, which is why the stability of different analytes should be investigated thoroughly in different temperatures. It should be born in mind that doctors are treating the patients based on the results they receive from the laboratory. To avoid possible malpractice, the analytical properties should remain reliable. Traditionally, some analyses have been carried out manually, which is known to be time-consuming and carries the possibility of wide intra-observatory mistakes. For that reason, it would be reasonable to perform some manual analyses, such as body fluid analysis, in an automated manner. Automating the manual steps taken in the laboratory would release labour for other tasks and may increase the cost-effectiveness of the work. Organisational changes have redirected the needs of a clinical laboratory towards automated options instead of manual ones and finding more economically-based alternatives to replace or complement traditional methods. / Tiivistelmä Laboratoriolääketiede on jatkuvan muutospaineen alla. Organisaatiomuutokset ja kilpailutus ovat saaneet aikaan sen, että laboratorioiden analytiikkatarjonnan tulee olla kilpailukykyistä niin hinnan kuin tulosten vastausnopeuden suhteen. Aikaisemmin pelkästään tutkimuskäytössä olleet menetelmät, kuten PCR ja massaspektrometri, ovat jalkautuneet jo keskussairaalatasoiseen tutkimusvalikoimaan. Organisaatiomuutokset ovat saaneet aikaan myös sen, että näytteet voidaan ottaa potilaasta alueellisissa toimipisteissä ja kuljettaa päivän aikana keskuslaboratorioon analysoitavaksi. Kuljetusmatkat ja -ajat saattavat olla hyvinkin pitkiä. Tämän johdosta on erittäin tärkeää selvittää näytteiden säilyvyys niin, että tulokset pysyvät luotettavina eikä potilaan hoito kärsi. Perinteisesti osa tutkimuksista, kuten punktionesteen solut, on tehty käsin mikroskopoimalla, jonka tiedetään olevan aikaa vievää ja näin ollen myös kallista analysointia. Kyseisen tutkimuksen siirtäminen analysaattoreille tehtäväksi voi tuoda laboratoriolle taloudellisen säästön lisäksi työvoiman vapautumista manuaalisesti suoritettavalta mikroskopoinnilta. Muutospaineet laboratoriotoiminnoissa ovat saaneet aikaan tarpeen automatisaation lisääntymiselle ja taloudellisempien vaihtoehtojen löytämiselle perinteisten menetelmien rinnalle tai niiden sijaan.
106

Elaboration d'une approche de vérification et de validation de logiciel embarqué automobile, basée sur la génération automatique de cas de test / Elaboration of an approach of check and validation of automobile embarked software, based on the automatic generation of case of test

Kangoye, Sékou 27 June 2016 (has links)
Un système embarqué est un système électronique et informatique autonome dédié à une tâche précise. Dans le secteur de l’automobile, le nombre de systèmes embarqués dans les voitures a considérablement augmenté au cours de ces dernières années et va certainement continuer à augmenter. Ces systèmes sont dédiés entre autres, à la sécurité, au confort de conduite,et à l’assistance à la conduite. Cette croissance des systèmes est associée avec une croissance en taille des logiciels qui les contrôlent. En conséquence, leur gestion(système et logiciel) devient de plus en plus complexe et problématique. Par ailleurs, la concurrence dans le secteur automobile est très féroce et les temps de mise sur le marché sont de plus en plus courts. Ainsi, pour garantir le bon fonctionnement des systèmes en général et du logiciel en particulier, étant donné leur complexité,et aussi les délais courts de mise sur le marché des produits automobiles, de nouvelles méthodes de développement doivent être considérées. Ainsi, de nombreuses méthodes de développement, incluant de nouveaux standards (de développement) et approches automatiques ont émergé au cours de ces dernières années. Dans le cas particulier de la vérification et validation de logiciel, une des activités critiques qui a connu une avancée significative est la génération de cas de test, avec l’avènement d’approches automatiques.Malgré cela, ces approches peinent souvent à s’imposer en milieu industriel. Une des raisons est que celles ci sont souvent peu adaptées ou peu utilisées dans un contexte industriel.Dans ce contexte, cette thèse vise à proposer une approche de vérification et de validation de logiciels embarqués, basée sur la génération automatique de cas de test. Pour cela, nous avons mis en place une approche permettant de représenter sous forme de modèles abstraits les spécifications d’un logiciel, puis de générer à partir de ces modèles un ensemble de cas de test en considérant en particulier le critère de couverture MC/DC. / An embedded system is a system that performs a specific task and has a computer embedded inside. In the automotive sector, the amount of embedded systems in the vehicle has risen dramatically in recent years and is set to increase. They deal essentially with safety, comfort, and driving assistance. Furthermore, the increase in number and complexity of the systems is associated with a growth in software. As a consequence, their management (system and software) have become more and more complex and problematic. Also, the competition and time-to-market in the automotive industry are very tough. Thus, to guarantee the efficiency and reliability of the embedded systems in the vehicle in general and the software in particular, in view of the complexity as well as the competition and time-to-market law, new development methods should be considered. Therefore, new development methods including new standards, and automatic approaches have emerged over the last years. In the particular case of embedded software verification and validation, one of the most critical activities that has experienced a significant progress is test case generation with the advent of automatic approaches. Despite this, these approaches are not widely used or are not well adapted in industrial context. In that context, our goal in this PhD. thesis is to propose a new verification and validation approach, based on automatic test case generation of embedded embedded. Thus, we have set up an approach that automatically generates test cases, with respect to the MC/DC criterion, from abstract models of the software specifications expressed in the form of state-transition models.
107

Implementace real-time operačního systému uC/OS-II na platformě Freescale MC9S08JM60 / Implementation of uC/OS-II Real-Time Operating System on Freescale MC9S08JM60 Platform

Vávra, Lukáš January 2013 (has links)
The term real-time operating system for embedded aplications has great importance today. This thesis descbires robitc arm control by mC/OS-II system on MC9S08JM60 platform. Robotic arm uses three servomotors HS-311 for motion, which are controlled by PWM. PWM pulse width is set according to the loaded data from the accelerometer, which is placed on DEMOJM board.
108

Strategické řízení firmy z oblasti zakládání a údržby zeleně

Macháč, Radim January 2017 (has links)
Macháč, R. Strategic management of gardening and landscaping company. Diploma thesis. Brno: Mendel University in Brno, 2017. The diploma thesis deals with strategic management of the company and its goal is to create variants of strategy and assess the current state of the company STROMMY COMPANY Ltd. and the market in which it operates. The partial aim is to implement strategic management of the company. To analyse the external environment is used PESTE analysis and Porter´s five force analysis. Internal environment is analyzed using a model 7S, analysis of internal resources and financial analysis. Based on the identification and analysis of key success factors there were used IE matrix and SWOT matrix and were formulated strategic recommendations and actions to implement strategic management.
109

Sprängningar & Kalasjnikovs : En kritisk diskursanalys av rapporteringen om förortsgäng och mc-gäng i svensk press. / Explosions and Kalasjnikovs. : A critical discourse analysis of the reporting on suburban gangs and motorcycle gangs in the Swedish press.

Kajsa, Morenius, Jimmy, Roth January 2021 (has links)
In the aftermath of the conflict between motorcycle clubs Hells Angels and Bandidos in the 90´s, with shootings that resulted in many casulties it seems that they have been silent since then. When a new conflict between gangs from the suburbs emerge it seems that they had taken the place of the motorcycle clubs in news media as the worst criminals in Sweden. The fact that motorcycle clubs are larger in number and tend to more criminal activities than the suburban networks, this study aims to make a greater understanding of how the two types of gangs are constructed and their representation in news media in the year of 2019.  Studies shows that suburban gangs sprout from especially vulnarble areas, that have low income and are the most immigrant-dense areas in Sweden. On the opposit side of suburban gangs, the motorcycle clubs show more of swedish-born members. It is interesting to see what type of representation the two different gangs get in news media. And how the representation and the construction differs depending on which gang that is described.  To go deeper in the analysis we used a critical discourse analysis (CDA) as a tool to answer our aim of this studie. The result was not surprising as the suburban gangs were constructed more often as the Other and seen as a problem caused by the immigration wave of 2015. The motorcycle club members was constructed more as individuals caught in the moment and triggered for some reason on a personal level. Motorcycle clubs were also constructed as a brotherhood where you could find comradeship and a sense of family.
110

Development of an event generator for antihyperon-hyperon pair production in antiproton-proton collisions

Shen, Vitor Jose January 2022 (has links)
The goal of this project was to develop a lightweight Monte-Carlo (MC) event generator for hyperon pair production in antiproton-proton collisions, and demonstrate it in one of the hyperon decay reaction channels, which is collisions of proton and antiproton to lambda hyperon and anti-lambda hyperon, and they decay to antiproton-positive pion pair, and proton-negative pion pair. The prototype of this external MC event generator we presented here is based on the software framework of ROOT. Compared to the corresponding framework of embedded MC event generators that is currently used in the PANDA experiment at FAIR, PandaRoot, it allows for easier and quicker testing of new models or formalisms on synthetic data, for example for studying spin observables like polarisation. The event generator was benchmarked by studying angular distributions in final states, which are constructed by kinematic relations of 4-momentum vectors in different reference frames for all mother and daughter particles.

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