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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.
111

Contribution au dimensionnement d'une liaison radio sur le corps humain :études canal et antenne à 60 GHz

Razafimahatratra, Solofo 14 November 2017 (has links) (PDF)
The band around 60 GHz is interesting for BAN applications mainly for lowerinterference than at microwave frequencies, wide available band adapted to On-Off Keying(OOK) modulation for low energy consumption and low data rate communication (under10 Mbps), antenna miniaturization. Nevertheless, due to high attenuation at this frequency,the design of a reliable and energy-effective communications for BANs requires a detailedanalysis of the body channel. A planar and compact SIW horn antenna was designed and usedfor body channel measurements at 60 GHz. The main contribution in the antenna design is thebandwidth enhancement covering the whole available band around 60 GHz compared to thesame antenna type available at this frequency. The on-body measurements with this antennashow that short-distance and LOS (Line Of Sight) links are possible at 60 GHz. The bodydynamic is taken into account by statistical off-body channel measurements. For the firsttime, measurements are done for the same scenarios at 60 GHz and another frequency in theUltra WideBand suitable with OOK impulse radio modulation. By taking into accounttransmission power standards and low power consumption receivers sensitivity in theliterature, the potentiality of 60 GHz for BAN is shown with an outage probability lower than8 % whereas this parameter is lower than 15 % at 4 GHz. When characterizing antenna onbody, difficulties arise for antenna de-embedding due to the antenna-body coupling. In fact,the antenna gain depends on transmitter-receiver distance on body. For the first time, aformulation of the vertical dipole gain on body is given. Also a new theoretical approachbased on the complex images method is proposed to compare two types of canonical antennaradiating on body. A vertical dipole and different rectangular apertures are normalizedthrough their input impedance with the same accepted power. The aperture input impedanceformulation has been developed during this study. The aperture efficiencies are 10% higherwhen antennas are at a height lower than 3 mm above the body phantom. The received powerincreases with the antenna size only for phantom direct touch, the difference among antennasis lower than 4 dB for the considered antennas limited with a monomode configuration. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished
112

Logics of Knowledge and Cryptography : Completeness and Expressiveness

Cohen, Mika January 2007 (has links)
An understanding of cryptographic protocols requires that we examine the knowledge of protocol participants and adversaries: When a participant receives a message, does she know who sent it? Does she know that the message is fresh, and not merely a replay of some old message? Does a network spy know who is talking to whom? This thesis studies logics of knowledge and cryptography. Specifically, the thesis addresses the problem of how to make the concept of knowledge reflect feasible computability within a Kripke-style semantics. The main contributions are as follows. 1. A generalized Kripke semantics for first-order epistemic logic and cryptography, where the later is modeled using private constants and arbitrary cryptographic operations, as in the Applied Pi-calculus. 2. An axiomatization of first-order epistemic logic which is sound and complete relative to an underlying theory of cryptographic terms, and to an omega-rule for quantifiers. Besides standard axioms and rules from first-order epistemic logic, the axiomatization includes some novel axioms for the interaction between knowledge and cryptography. 3. Epistemic characterizations of static equivalence and Dolev-Yao message deduction. 4. A generalization of Kripke semantics for propositional epistemic logic and symmetric cryptography. 5. Decidability, soundness and completeness for propositional BAN-like logics with respect to message passing systems. Completeness and decidability are generalised to logics induced from an arbitrary base of protocol specific assumptions. 6. An epistemic definition of message deduction. The definition lies between weaker and stronger versions of Dolev-Yao deduction, and coincides with weaker Dolev-Yao regarding all atomic messages. For composite messages, the definition withstands a well-known counterexample to Dolev-Yao deduction. 7. Protocol examples using mixes, a Crowds style protocol, and electronic payments. / QC 20100524
113

Research on Assemblies and Parades Handled by Police Organizations Analysis the cases of assemblies and parades in Kaohsiung City ¡]during the period from 2001 to 2005¡^

Si, Dong-Li 11 August 2005 (has links)
This paper is mainly anchored in assemblies and parades handled by police agency¡¨. First of all, assemblies and parades are the basic human rights protected by our constitution. The purpose of the police¡¦s involvement in the handling of those activities is to safeguard citizens¡¦ exercise of their rights. Secondly, from analysis of practical cases and through verification of experimental activities and modification of theories, reasonable and proper principles of handling such activities can be submitted as a reference for policemen¡¦s law enforcement and education and training. Finally, the study discusses the contents and regulations of the Law of Parade and Demonstration. It also provides directions of modification of the law through theories and experiments in order to make the law more perfect, protect human rights granted by the constitution, and further inspire people¡¦s law-abiding spirit. From my practical experiences in handling assemblies and parades over the years in police organizations of basic level and this study, the author found that the cases of assemblies and parades in Kaohsiung City during the period from 2001 to 2005 were different in their types. Case-by-case analysis, examination of evidence and deductive method were adopted to examine if the police adhere to the principles of ¡§protecting lawful assemblies¡¨, ¡§banning unlawful assemblies, and ¡§imposing sanction against violence¡§, and if they take the positions of ¡§To rule by law¡¨, ¡§administrative neutrality¡¨ and ¡§strict enforcement of law¡¨ at the same time. If not, the results will turn out to be different. In recent years, people¡¦s political consciousness has been rising and the assertion of individual rights and interests has aroused more and more attention. Besides, the two-party system has almost taken shape in Taiwan. Consequently, assemblies and parades become normal in today¡¦s plural and diversified society. The police should know how to play the role of law enforcement and protector correctly. To achieve the goal, the policemen should accumulate their practical experiences and carry out case analysis continuously. By combining ¡§theories¡¨ with ¡§practices¡¨ together, this study reflects the advantages and disadvantages of the police in handling assemblies and parades at current stage, and point out the direction of amendment to the present Law of Parade and Demonstration. Finally, this study submits one set of concrete and feasible plan for the police agency to follow, and I hope that the plan will be helpful in handling assemblies and parades in the future.
114

Subsurface radioactive gas transport and release studies using the UTEX model

Lowrey, Justin David 15 October 2013 (has links)
Underground nuclear explosions (UNEs) produce anthropogenic isotopes that provide the only definitive means by which to determine whether a nuclear explosion has taken place. Verification of a suspected test under the Comprehensive Nuclear-Test-Ban Treaty (CTBT) includes both on-site and atmospheric sampling of specific noble gas radioisotopes for analysis of origin. It is well-established that the processes of subsurface transport can affect the rate at which such gases will reach the surface. However, the relative abundance of anthropogenic isotopes reaching the surface following transport is currently assumed to rely solely on their direct fission yield, decay rate, and their production from precursor decay, making no account for the influence of transport processes on isotopic ratios. The Underground Transport of Environmental Xenon (UTEX) model has been developed to examine the possible effects of subsurface transport on radioxenon isotopic ratios as well as to consider a number of on-site inspection-related applications. In this work, background on the UTEX model's development, evolution and vetting is presented. This is followed by the characterization and analysis of a number of applications of the model for consideration of CTBT-relevant scenarios. Specifically, the UTEX model's capability to analyze CTBT on-site inspection concept of operations is demonstrated. This is accomplished through an examination of generalized UNE source terms, geological stratigraphy, UNE impact on local geology, natural soil-gas radionuclide backgrounds, atmospheric infiltration, and sampling methodology. It is shown that the processes driving noble gas transport through geological media can significantly skew the ratios of key radioxenon isotopes that are used to help verify whether or not a well-contained underground test has taken place. This result emphasizes the need for a broader understanding of radionuclide signatures used for CTBT verification purposes and the mechanisms that can alter them. / text
115

Dielectric Resonator Antennas (DRA) for satellite and body area network applications

Alam, Muhammad Faiz, Alam, Muhammad Faiz 02 July 2012 (has links) (PDF)
Technologies such as direct broad cast satellite system (DBSS), Geosynchronous Earth Orbit (GEO) and Low Earth Orbit (LEO) satellite communications , global positioning system (GPS), high accuracy airborne navigation system and a large variety of radar systems demand for high level of antenna performance. Similar is the requirement for upcoming land based wireless systems such as cellular and indoor communication systems that is needed some more specific and additional features added to the antenna to compensate for the deficiencies encountered in system's performance. Though metallic antennas are capable enough to fulfil all the operational requirements, however at very high frequencies and under hostile temperature conditions they are constrained to face certain limitations. To avoid these constraints the performance of Dielectric Resonator Antennas (DRAs) is evaluated and their new applications are proposed. In the thesis, two types of antenna applications are sought :-First is for tracking and satellite applications that needs a larger aperture coverage in elevation plane. This coverage is realized with a good CP purity by proposing two ports dual linearly polarized DRA working at X-band. The DRA is excited by two orthogonal H-shaped aperture slots yielding two orthogonal polarizations in the broadside direction. A common impedance bandwidth of 5.9% and input port isolation of -35 dB are obtained. The broadside radiation patterns are found to be highly symmetric and stable with cross polarization levels -15dB or better over the entire matching frequency band. The maximum measured gain is found to be 2.5dBi at 8.4 GHz.- The 2nd type of antenna is a dual pattern diversity antenna to be used in the Body Area Network (BAN) context. This antenna combines a slot loop and DRA yielding broadside and end-fire radiation patterns respectively. Based upon the feeding techniques, the DG antenna is further divided into two categories one with planar feeds and the other with non-planar feeds (slot loop excited by planar CPW but DRA excited by vertical monopole) .Both types are successfully designed and measured upon body when configured into different propagation scenarios. The non-planar feeds antenna allows wider common impedance bandwidths than the planar feeds (4.95% vs 1.5%).In both cases, a maximum value of DG=9.5dB was achieved when diversity performance tests were carried out in rich fading environments. This value is close to the one (10 dB) theoretically reached in a pure Rayleigh environment and was obtained with efficiencies of 70% and 85% for the slot loop and the DRA respectively. Therefore, we conclude that these antennas could be used on the shoulders or the chest of professional clothes (firemen, policemen, soldier) where full planar integration is not a key issue but where the communication must be efficient in harsh environments and for various gestures, positions and scenarios
116

Distributed Data Management Supporting Healthcare Workflow from Patients’ Point of View

Ayoubi, Tarek January 2007 (has links)
Patient’s mobility throughout his lifetime leaves a trial of information scattered in laboratories, clinical institutes, primary care units, and other hospitals. Hence, the medical history of a patient is valuable when subjected to special healthcare units or undergoes home-care/personal-care in elderly stage cases. Despite the rhetoric about patient-centred care, few attempts were made to measure and improve in this arena. In this thesis, we will describe and implement a high-level view of a Patient Centric information management, deploying at a preliminary stage, the use of Agent Technologies and Grid Computing. Thus, developing and proposing an infrastructure that allows us to monitor and survey the patient, from the doctor’s point of view, and investigate a Persona, from the patients’ side, that functions and collaborates among different medical information structures. The Persona will attempt to interconnect all the major agents (human and software), and realize a distributed grid info-structure that directly affect the patient, therefore, revealing an adequate and cost-effective solution for most critical information needs. The results comprehended in the literature survey, consolidating Healthcare Information Management with emerged intelligent Multi-Agent System Technologies (MAS) and Grid Computing; intends to provide a solid basis for further advancements and assessments in this field, by bridging and proposing a framework between the home-care sector and the flexible agent architecture throughout the healthcare domain.
117

Zákaz rasové diskriminace v mezinárodním právu a jeho aplikace v právním řádu České republiky / Ban on racial discrimination in international law and its application in the legal order of the Czech Republic

Pačesová, Martina January 2014 (has links)
This thesis deals with the ban on racial discrimination and protection against it in international law and its application in the legal order of the Czech Republic. The aim of this study was to examine the provisions prohibiting racial discrimination and mechanisms of protection against racial discrimination established by various conventions on the international and European level and the status of implementation of these commitments in the legal order of the Czech Republic and their implementation. The work is divided into six chapters; the issue itself is divided into four. In the second chapter thesis provides a definition of basic terms such as equality and its subdivisions, equal treatment, discrimination, its forms and discriminatory law and how the very nature of this work is apparent as well as the terms of race, racial discrimination, racial segregation and violence. In third and fourth part are introduced systems of protection against racial discrimination in the United Nations, the Council of Europe and the European Union. The fifth chapter is concerned with Czech legislation, the process of application of the ban on racial discrimination into the Czech legal order, on the constitutional level as well as on the level of laws, which also outlines the procedural particularities of the...
118

Lobbing jako nástroj k utváření evropské legislativy: případ zákazu testování kosmetiky na zvířatech / Lobbying as a tool for shaping European legislation: the case of a ban on animal testing of cosmetics

Krhlová, Martina January 2017 (has links)
This diploma thesis looks at lobbying as one of the tools for shaping European legislation. Lobbyists are often perceived as carriers of valuable information that make it possible for decision-makers to get expert opinions and perspectives directly from the industry. Lobbyists can therefore make a significant contribution to policy making and to improving European legislation that meets the needs of stakeholders. The main objective of the thesis is to find out in what way and at what stages the interest groups participate and intervene in the EU decision-making process and identify the access points through which they can enter into the legislative process. For the sake of clarity, this research is applied to a particular case of lobbying in the field of animal testing of cosmetics, which has greatly influenced the legal regulation of the area.
119

Transnational civil society's ability to successfully influence state actors on human rights issues through international non-governmental organizations (INGOs) : a case study of the coalition to stop the use of child soldiers

VerHage, Alicia January 2009 (has links)
The international dilemma of child soldiers is a humanitarian concern throughout the world. The Coalition to Stop the Use of Child Soldiers (CSUCS) began in 1998 and is currently the leading collaborative movement to address the issue. However, because of its emphasis on a universal 'Straight 18' approach and support of the Optional Protocol of the Convention on the Rights of a Child (CRC), the CSUCS ignores contextual realities that affect the implementation ofthe international legislation and the development of norms concerning child soldiers. This research project will examine the current international nongovernmental organization (INGO) response to child soldiers- focusing on the CSCUS - and formulate suggestions for potential avenues to further INGO involvement with policies and projects. The argument is based on a neoliberal institutionalist platform that argues in favour ofiNGOs' ability to successfully influence actions taken by state actors to address human right issues. Highlighting the successful INGO influence on states during the International Campaign to Ban Landmines, I will present this example as a potential model for the Coalition to Stop the Use of Child Soldiers, and explore the feasibility of this model whilst making suggestions for more effective involvement of INGOs with regard to the issue of child soldiers.
120

Réseaux corporels sans fil en ondes millimétriques : antenne, propagation et interaction avec le corps / Wireless body area networks in millimeter waves : antenna, propagation and interaction with the body

Leduc, Caroles 07 December 2015 (has links)
Récemment la bande 60 GHz a été mise en avant pour le développement des réseaux de communication sans fil centrés sur le corps humain. Cet intérêt de la bande 60 GHz pour les applications BAN (Body Area Network) s'explique par les avantages clefs qu'elle procure par rapport aux bandes de fréquence plus basses (possibilité de débits de données supérieurs à 7 Gbit/s, réduction des interférences avec les réseaux voisin, compacité des dispositifs, etc). Le nombre d'application de communication BAN est amené à croître dans les années à venir avec le déploiement de la 5ème génération de réseaux de télécommunications mobiles. Afin de protéger efficacement les utilisateurs des expositions générées par ces applications BAN à 60 GHz, il est nécessaire de se pencher sur les problématiques de réduction du couplage corps/antennes, mais également sur l'évaluation et la quantification du niveau d'exposition du corps à 60 GHz. Pour cela, les travaux de thèse ont été organisés suivant trois axes de recherche : le premier consiste à mettre en évidence et à quantifier l'impact de certains choix de conception en matière d'antennes sur le couplage avec le corps humain ; le second porte sur les outils et les méthodes utilisés pour estimer l'impact thermique d'une exposition électromagnétique 60 GHz sur le fantôme équivalent de la peau ; et le troisième propose une nouvelle approche à la fois dosimétrique et thermique pour évaluer et analyser le couplage corps/antennes en bande millimétrique. / The 60-GHz frequency band has been identified recently as attractive for body centric wireless communication development. Indeed, this band has several key advantages compared to lower frequency bands as high data rates above 7 Gbit/s, low risks of interference with neighboring wireless networks and compact devices. With the development of the future 5th generation of mobile networks in the millimeter-wave band, the number of BAN applications at 60 GHz should increase. To avoid health effects and protect user against an electromagnetic exposure of BAN devices at 60 GHz, the reduction of the coupling between human body and antennas, as well as the evaluation and quantification of exposure are main research aspect of the thesis. The main thesis contributions are divided in three parts: a quantification of antenna design effects on the interactions between human body and antennas; a study of tools and methods used to assess thermal effects due to 60 GHz exposure on a skin-equivalent phantom; and a new dosimetric and thermal approach to evaluate interaction between human body and BAN antennas at 60 GHz.

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