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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.
41

A Real-time Counting-measuring Method for PPM(PPK) Signals

Xi-Hua, Li 11 1900 (has links)
International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / On the disscussion of custom real-time counting-measuring method, this paper presents a new method suitable for the working condition of non-man duty, which possesses the feature of 100ns counting-measuring accuracy and high fidelity. In addition, the concept of “Signal-time/digit converter” is proposed for the first time and the principle and working procedure of this method are introduced in brief.
42

Secure Text Communication for the Tiger XS

Hertz, David January 2006 (has links)
<p>The option of communicating via SMS messages can be considered available in all GSM networks. It therefore constitutes a almost universally available method for mobile communication.</p><p>The Tiger XS, a device for secure communication manufactured by Sectra, is equipped with an encrypted text message transmission system. As the text message service of this device is becoming increasingly popular and as options to connect the Tiger XS to computers or to a keyboard are being researched, the text message service is in need of upgrade.</p><p>This thesis proposes amendments to the existing protocol structure. It thoroughly examines a number of options for source coding of small text messages and makes recommendations as to implementation of such features. It also suggests security enhancements and introduces a novel form of stegangraphy.</p>
43

Secure Text Communication for the Tiger XS

Hertz, David January 2006 (has links)
The option of communicating via SMS messages can be considered available in all GSM networks. It therefore constitutes a almost universally available method for mobile communication. The Tiger XS, a device for secure communication manufactured by Sectra, is equipped with an encrypted text message transmission system. As the text message service of this device is becoming increasingly popular and as options to connect the Tiger XS to computers or to a keyboard are being researched, the text message service is in need of upgrade. This thesis proposes amendments to the existing protocol structure. It thoroughly examines a number of options for source coding of small text messages and makes recommendations as to implementation of such features. It also suggests security enhancements and introduces a novel form of stegangraphy.
44

NOT THE SHARPEST TOOL IN THE BOX : A quantitative study of the reliability of the Sharpe ratio in a Bear market

Short, Wesley James, Lind, Jan Oskar January 2010 (has links)
Our thesis was conducted through quantitative research on the validity of the Sharpe ratio as a performance measure in bear market conditions. Previous research had identified problems with mismatches in ranking due to Sharpe ratios rewarding unsystematic risk in funds. Alternative Sharpe  ratios have been developed to solve this problem; Scholz (2006) developed the Normalized  Sharpe ratio, which he argued to be a more valid performance measure in bear market conditions. We conducted a comparative analysis between rankings of the Sharpe ratio and Scholz Normalized Sharpe ratio to find out whether the Sharpe ratio provides mismatches in ranking due to rewarding unsystematic risk. The research was conducted on Swedish premium pension funds within the Swedish Pension system. We aimed to highlight the potential problems with interpreting the Sharpe ratio in bear market periods. Various models and theories was utilized to support our research question and attempt to link them to our quantitative analysis. The results from our analysis showed us that there were mismatches between the different ratios, additionally our findings provided support to previous researchers’ conclusions which stated that  the Sharpe ratio rewards unsystematic risk.
45

Modelos baseados em PPM para previsão de trajetórias utilizando informações contextuais.

NOBRE NETO, Francisco Dantas. 03 May 2018 (has links)
Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-05-03T21:26:06Z No. of bitstreams: 1 FRANCISCO DANTAS NOBRE NETO – TESE (PPGCC) 2017.pdf: 3110801 bytes, checksum: e2803429a1a01abf91502c50bc0ea1df (MD5) / Made available in DSpace on 2018-05-03T21:26:06Z (GMT). No. of bitstreams: 1 FRANCISCO DANTAS NOBRE NETO – TESE (PPGCC) 2017.pdf: 3110801 bytes, checksum: e2803429a1a01abf91502c50bc0ea1df (MD5) Previous issue date: 2017-05 / Com a ampla difusão de smartphones equipados com dispositivos GPS (Global Positioning System), rastrear a localização de objetos (como pessoas e veículos) tem sido uma tarefa mais factível, resultando em novas oportunidades de pesquisas em variadas áreas do conhecimento. Dentre estas oportunidades, esta pesquisa lida com o desafio da área de previsão de rotas e destinos. Saber antecipadamente o destino de um usuário assim que ele inicia um deslocamento tem muitas utilidades práticas, tais como: indicar rotas menos congestionadas ou vias mais seguras, e sugerir a visita a algum ponto de interesse (POI) antes do destino almejado. Sistemas que fornecem previsão de rota e destino estão disponíveis comercialmente, no entanto, estes podem requerer interações constantes do usuário. Para deslocamentos diários, porém, a necessidade de uma interação frequente do usuário com um aplicativo pode tornar seu uso pouco prático e pouco ubíquo. Além disso, muitos trabalhos que apresentam modelos de previsão de rotas e destinos, disponíveis na literatura, não contemplam uma importante informação contextual, que é o papel que os lugares visitados representam para um usuário (por exemplo, se é sua casa ou seu local de trabalho). Não obstante, a maioria dos preditores disponíveis não possuem a funcionalidade de prever lugares nunca visitados. Esta tese de doutorado propõe uma família de métodos de predição baseada no algoritmo de compressão de dados Prediction by Partial Matching (PPM). Ainda com relação a esta pesquisa, é proposto um mecanismo capaz de identificar que uma rota em curso está sendo realizada pela primeira vez e, portanto, ter a possibilidade de prever um destino ainda não visitado. Neste estudo, também foram implementados outros preditores consolidados na literatura, que são as Cadeias de Markov e as Cadeias Ocultas de Markov, utilizados para comparação. É importante observar que ambos os preditores são capazes de prever apenas o destino de um trajeto, ao invés da rota restante. Nos experimentos realizados, foram utilizadas as métricas de Precisão, Recall e Medida-F (F1 Score), com validação cruzada (contendo 10 partições mutuamente exclusivas), para avaliação dos modelos de previsão implementados. A base de dados utilizada nesta pesquisa é composta por mais de 1.500 rotas, coletadas por aproximadamente três meses, referentes a 21 usuários. Os preditores baseados em PPM apresentaram resultados competitivos (ou superiores) comparados aos da literatura. / Thanks to the widely diffusion of smartphones with GPS devices natively embedded, the task of tracking object locations, such as people or vehicles, is more feasible nowadays, fostering new research opportunities. Among these new opportunities, this work addresses the challenge of route and destination prediction. Knowing in advance the destination where a user might reach as soon as he or she starts to move can be useful in various situations. For instance, to suggest to users less jammed or safer routes, as well to warn about points of interest located along their route. There are commercial systems capable of predicting destination and routes, however, these systems usually require frequent user interaction. Nonetheless, such a requirement could make the application unusable for daily routines. Moreover, most existing works do not consider an important contextual information: the information about the places that the users visit, i.e., the role that the places play to the user (for instance, if the place is home or work). In addition, most predictors described in the literature are not able to predict places that users have never visited. This thesis proposes a family of algorithms based on Prediction by Partial Matching (PPM). Furthermore, this work proposes a mechanism for identifying whether a route is being performed for the first time, resulting in the feasibility for predicting a never visited place. This research also provides a comparison between our proposed predictors, and the predictors based on Markov Models and Hidden Markov Models (HMM), which have been used in related works. It is important to mention that both Markov and HMM predictors that we implemented are able to predict just the destination, instead the remaining route. For the statistical assessment of the predictors, the metrics Precision, Recall and F1 Score are used, together with the process of 10-fold cross- validation. The database contains about 1,500 routes extracted from 21 users, gathered for three months. The predictors based on PPM performed similarly (or better) than others reported in the literature.
46

Výběr a implementace open source nástroje pro řízení portfolia projektů / Selection and implementation of open source project and portfolio management tool

Kučera, Jan January 2009 (has links)
Companies and other organizations have to change and adapt their strategies and redefine their goals constantly. Actions and steps that are needed in order to achieve the defined goals and to realize the change are often executed in a form of a project. There is no doubt that projects need to be managed in an appropriate way. In organizations where there are more than one project executed in parallel and other projects are being planned or proposed at the same time it is necessary to manage not only the individual projects but the entire portfolio of projects and programmes. Portfolio management is needed to ensure that the selected projects are best aligned with the defined goals and the strategy but this requires an analysis of a large amount of data about current and upcoming projects or about available resources and their utilization. It is not always easy to get all required data and to perform the analysis. This is the reason why deployment of some project and portfolio management software tool should be considered. This thesis deals with a search for suitable open source project and portfolio management tools and with assessment of costs and benefits of deployment of selected open source tool in a hypothetical IT company. The goal of this thesis is to define the term project and portfolio management tool and to find at least five open source tools of this type that are suitable for deployment in an organization. At least one of these tools should be suitable for deployment in the IT company. Another goal is comparison of features and functionality provided by the open source tools with functionality provided by the robust proprietary project and portfolio management solution deployed on premise and with one solution offered in the Software-as-a-Service model. Creation of a business case dealing with implementation of the selected open source tool is the last goal of this thesis. Identification and description of available open source tools and comparison of these tools with representatives of the robust project and portfolio management tools developed and distributed in models different from open source are considered the main benefits of this thesis. The terms "open source software" and "project and portfolio management tool" are defined in the first part of this work. The definition of terms is followed by the definition of the overall approach to the assessment of the open source tools which involves definition of assessment criteria and obligatory requirements. Next part of the work is dedicated to the selection of the open source tools that are suitable for deployment in an organization and which represent candidates for project and portfolio management tools. Assessment of these tools using the defined criteria is performed as the next step which is followed by the comparison with representatives of proprietary project and portfolio management tools. Last part of the work is dedicated to the business case which deals with deployment of the selected open source tool. This work concludes with discussion whether the defined goals were met or not, and with the summary of the results.
47

Selection and implementation of open source tool for project portfolio management / Výběr a implementace open source nástroje pro řízení portfolia projektů

Marek, Jan January 2016 (has links)
Methods and ways of implementation of changes and innovations in companies through project management are in today's society very well established. There exists methodologies, techniques and tools for the management of individual projects. However in a role of project manager, I very often faced the fact that companies are performing the project portfolio management in very intuitive way. This in itself leads to failed and prematurely terminated projects, initiation of the wrong projects or realisation of correct projects, but at the wrong time. Very often I have also recognized, that there is lack of awareness of fact, that there are also Open Source applications that can help with the organization's portfolio. This thesis deals with the definition of requirements, search and selection of proper OSS application and subsequent implementation. In the first part of this thesis I prepare a theoretical framework about PPM, and on that basis then identify and verify a set of requirements for selection of right OSS PPM application. The next section of thesis describes searching for suitable applications from a variety of sources, assessment against the requirements and the final selection. In the last part the implementation project is drafted, which aims to serve other colleagues in project management as one of the possible implementation paths. The outputs are then continuously confronted with experts in matter of projects and project management in the field of IT in order to maximize symbiosis between theory and real life experiences. Virtually every project management methodology defines the collection of already-proven techniques, best practices or lessons learned from the previous similar implementations. The main contribution of this thesis I see in fact that it contains not only the design of the project implementation, but also describes a logical path, what leads to the result. Therefore this thesis could be used as a base or discussed best practice, when a project of implementation of PPM application in place.
48

Normalisering av ett högerpopulistiskt parti? : En kvalitativ fallstudie om Nationella Frontens utveckling mellan 2002 och 2017

Liljestrand, Tove January 2022 (has links)
This essay refers to analyse how the French far-right party National Front was able to establish themselves in 2002 and how they continued to develop from the presidential election of 2002 to the most recent presidential election of 2017. The thory used to analyse regards the establishment and development of far-right parties and the model of PPM, standing for the policy process model and concerns factors of political opportunities, mobilisation and the political master frame, is used to analyse the party. The model is later applied to the National Front from 2002 to 2017 by reading existing work on the subject to find a result and examine hoe the development has shown. The conclusion of the analysis is that they have used the opportunities they have gotten from other parties as they have legitimised the party. But still, little difference is to be seen in the party's political master frame, the biggest difference is regarding the party's discourse where the current leader of the party, Marine Le Pen, has wanted to differentiate her leadership and the party from how it was during the former leader, Jean-Marie Le Pen.
49

Hygiene Routines in the Students Clinic - Compliance, Attitude and the Student's View on Knowledge at Malmö University of Dentistry

Nord, Johan, Lindskog, Stefan January 2016 (has links)
SAMMANFATTNINGInledning: Vårdrelaterade infektioner har under den senaste tiden fått stor uppmärksamhet inom vård och omsorg. Dessa infektioner kostar samhället miljontals kronor varje år och dessutom ökar användningen av antibiotika tillsammans med utvecklingen av antibiotikaresistens. Det bästa sättet att motverka resistensutveckling och vårdrelaterade infektioner är att vara noga med basala hygienrutiner och handdesinficering. Syfte: Undersöka följsamhet, attityd och studenternas syn på deras egen kunskap för hygienrutinerna vid Tandvårdshögskolan i Malmö.Material och Metod: Vi har undersökt, genom punktprevalensmätning, hur tandläkarstudenterna vid Tandvårdshögskolan i Malmö följer de riktlinjer som Socialstyrelsen har utformat vid patientnära arbete. Synen på kunskap och attityd har utvärderats genom en webbaserad enkät som skickats ut till samtliga studenter som går i kurs 3 till och med kurs 10.Resultat: Tandläkarstudenterna följer riktlinjerna som Socialstyrelsen utformat väl på alla punkter utom handdesinficering och användandet av plastförkläde. Genom webbenkäten kan man se att studenterna medvetet struntar i att använda plastförkläde p.g.a. att det blir för varmt. Studenterna anser sig ha god kunskap och anser sig följa rutinerna för handdesinficering fullt ut men observerad följsamhet säger det motsatta. 60-80% av studenterna struntar i eller glömmer handdesinfektion under patientbehandling. Konklusion: Studenterna brister i följsamhet för handdesinfektion och användning av plastförkläde. Studenterna ser kurskamrater bryta mot hygienrutiner men säger inte till. Studenterna övervärderar sin egen följsamhet jämfört med vad som observerats. / ABSTRACTIntroduction: Hospital-acquired infections are a burden to society with an annual cost of millions of SEK. The use of antibiotics and the development of antibiotic resistance are on the increase. The most efficient way to counteract development of antibiotic resistance and hospital-acquired infections is to be immaculate with the basic hygiene routines and to disinfect the hand before and after every patient encounter.Aim: Evaluate student compliance, view on knowledge and attitude regarding basic hygiene routines set by the National Board of Sweden at Malmö University of Dentistry.Materials and methods: In this study, a point prevalence measurement has been carried out at the student’s clinic at Malmö University of Dentistry. Furthermore, knowledge and attitude towards the routines have been evaluated with a web-based survey sent out to students at the faculty.Results: Results of this study show that the students follow the National guidelines well, except for the use of apron and the disinfection of their hands during treatment sessions. In contrast to the aprons, the students consider themselves correctly following the routines of disinfection and also have knowledge about how it should be carried out and when. Analysis of the point prevalence measurement shows that 60-80 % of the students fail to follow the routines of hand disinfection. Conclusion: The students lack in compliance regarding to hand disinfection and the use of apron. They see their classmates violate the guidelines but do not inform them of the violation. The students overestimate their own compliance compared to what have been observed.
50

Estudo numÃrico do acoplador duplo simÃtrico de fibras Ãpticas operando com PPM e PAM para obtenÃÃo de portas lÃgicas / Numerical study of symmetrical double coupler for fiber optic operating with PPM and WFP to obtain gate

Alisson da ConceiÃÃo Ferreira 22 January 2008 (has links)
CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / Neste trabalho, foram investigadas as caracterÃsticas de operaÃÃo de um Acoplador Direcional NÃo-Linear(NLDC) Duplo SimÃtrico, trabalhando com pulsos de , em duas diferentes aplicaÃÃes: ObtenÃÃo de portas lÃgicas E e OU, sob ModulaÃÃo Por PosiÃÃo de Pulsos (PPM); obtenÃÃo de portas lÃgicas E e OU, sob ModulaÃÃo Por Amplitude de Pulsos (PAM). A investigaÃÃo à realizada, atravÃs de simulaÃÃes numÃricas, utilizando-se do mÃtodo de Runge Kutta de quarta ordem. Na primeira aplicaÃÃo, à analisada a possibilidade da realizaÃÃo de operaÃÃes lÃgicas pelo Acoplador Direcional NÃo-Linear (NLDC) Duplo SimÃtrico sem perda. Considerando a operaÃÃo das portas lÃgicas, foram utilizadas as quatro possÃveis combinaÃÃes para dois pulsos, nas fibras 1 e 2, modulados pela posiÃÃo temporal (PPM) nos nÃveis lÃgicos 0 ou 1. Foram investigados os efeitos de uma variaÃÃo no parÃmetro de ajuste da modulaÃÃo PPM, ou seja, no deslocamento inicial do pulso em relaÃÃo ao pulso referencial, ou informaÃÃo nÃo modulada, e na diferenÃa de fase entre os pulsos sÃlitons fundamentais de entrada devidamente modulados. Na segunda aplicaÃÃo, o NLDC duplo simÃtrico à submetido à modulaÃÃo PAM, utilizando-se tambÃm, das quatro combinaÃÃes possÃveis para os dois pulsos, nas fibras de entrada. Foram investigados os efeitos da variaÃÃo no parÃmetro de ajuste da modulaÃÃo PAM na amplitude inicial do pulso em relaÃÃo à amplitude de referÃncia, ou sinal sem modulaÃÃo, e tambÃm observada a amplitude de saÃda modulada versus uma diferenÃa de fase entre os pulsos sÃlitons fundamentais de entrada devidamente modulados. Nas duas aplicaÃÃes foram obtidas portas lÃgicas E e OU. / In this work, the performance study of a Symmetric Dual-Core Non-Linear Directional Coupler (NLDC), working with pulses of , in two different applications have been investigated: accomplishment of logical gates AND and OR, under Pulse Position Modulation (PPM); accomplishment of logical gates AND and OR, under Pulse Amplitude Modulation (PAM). The investigation is based in a numerical simulation study, using the fourth order Runge Kutta numerical method. In the first application, the possibility of the accomplishment of logical operations by Symmetric Dual-Core Non-Linear Directional Coupler (NLDC) without loss is analyzed. Considering the operation of the logical gates, the four possible combinations for two pulses, on the input fibers, modulated by the temporal PPM in the logical levels 0 or 1, were used. The effects of a variation in the coding parameter offset of the PPM modulation, that is, in the displacement of the input pulse relative to the reference time level, was investigated. In the second application, the symmetric dual-core NLDC is submitted to PAM modulation, using the four possible combinations for two pulses on the input fibers, were used, as well. The effects of a variation in the coding parameter offset of the PAM modulation relative to the reference amplitude, was investigated. The modulated output amplitude versus a phase difference between the input pulses , was also studied. On the two applications, logical gates AND and OR was observed.

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