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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.
21

Public Private Partnership na příkladu Švýcarska / Public Private Partnership as an example in Switzerland

Koláčková, Leona January 2008 (has links)
This Graduation theses is conversant with difficulties of project Public Private Partnersip (for short PPP) with a view on it in Switzerland. In letter and spirit is general characterization of these Projections with the aim of consider potential benefits and disavantages with orientation of selective subjects on territory of Switzerland confederation. Further is task focused on economics and financial aspects these projects and compare of two approach to implementation purpose (alternate conventional and alternate PPP) on example of project realized in this country.
22

Projekty spolupráce soukromého a veřejného sektoru (PPP) v zemích Visegrádské čtyřky / PPP (Public Private Partnership) Projects in the countries of Visegrad Four

Slánská, Marie January 2008 (has links)
The diploma thesis is concerned with the problems of PPP projects (Public Private Partnership) in the countries of Visegrad Four. The term PPP can be understood as a cooperation of public and private sector. The principal aim of cooperation is to ensure public infrastructure and services. First part of thesis characterizes coutries of Visegrad Four, explains principles and benefits of PPP and informs about main countries and sectors in which PPP projects are realized. The core of the thesis is the fourth chapter which analyzes and evaluates V4 coutries on the basis of several criteria (legislation, institutional support, methodics and realized projects) and attempts to find out if those criteria influence the implementation and number of PPP projects in V4. Final part points out that PPP projects can be helpful for states in times of financial crisis to finance services or infrastructure if they do not have enough money.
23

Remarks on the quality of GPS precise point positioning using phase observations

Shirazian, Masoud January 2012 (has links)
GPS processing, like every processing method for geodetic applications, relies upon least-squares estimation. Quality measures must be defined to assure that the estimates are close to reality. These quality measures are reliable provided that, first, the covariance matrix of the observations (the stochastic model) is well defined and second, the systematic effects are completely removed (i.e., the functional model is good). In the GPS precise point positioning (PPP) the stochastic and functional models are not as complicated as in the differential GPS processing. We will assess the quality of the GPS Precise Point Positioning in this thesis. To refine the functional model from systematic errors, we have 1) used the phase observations to prevent introducing any hardware bias to the observation equations, 2) corrected observations for all systematic effects with amplitudes of more than 1cm, 3) used undifferenced observations to prevent having complications (e.g. linearly related parameters) in the system of observation equations. To have a realistic covariance matrix for the observations we have incorporated the ephemeris’ uncertainties into the system of observation equations. The above-mentioned technique is numerically tested on the real data of some of the International GNSS Service stations. The results confirm that undifferenced stochastic-related properties (e.g. degrees of freedom) can be reliable means to recognize the parameterization problem in differenced observation equations. These results also imply that incorporation of the satellite ephemeris uncertainties might improve the estimates of the station positions. / QC 20120503
24

Revenue Risk Management for P3 Highway Projects: Implementation of Revenue Guarantees in the U.S. Market

Shan, Liang 24 June 2010 (has links)
The Public-Private Partnership (P3 or PPP) model has been proposed as an alternative delivery system to address funding shortage problems associated with large-scale projects. Appropriately allocating and managing risks among project participants is critically important for a P3 project's success. This thesis focuses on one of the tools to manage revenue risk, the revenue guarantee, where a guarantor compensates a concessionaire with a predetermined amount of revenue in the event of a revenue shortfall. It is a form of real option—specifically a put option if a premium is paid for the downside protection or a collar option if potential upside revenue is traded for the protection. Previous research has explored the purpose and valuation of revenue guarantee options. This study focuses on the feasibility of utilizing a guarantee in US P3 highway projects through preparatory study and field investigation. In the preparatory phase, the work examines existing revenue risk management methods and how revenue guarantee options supplement them while also proposing an implementation framework. Additionally, it discusses a new option type,a collar option, including its concept, benefits, applicability, and valuation. In the field investigation phase, the preparatory work is synthesized into interview protocols that are used to seek market perspectives on revenue risks and revenue guarantee feasibility. Twenty people representing government officials, concessionaires, financial advisors and lending institutions were interviewed. The interview results indicated that a revenue guarantee shows promise as a viable tool, and the government should be willing to provide one. The decision to utilize a revenue guarantee depends on funding method selection, a public agency's institutional capacity, and the effectiveness of alternative risk mitigation approaches. Suggestions for implementation, such as applicable projects and a guarantee triggering criterion, are also provided. / Ph. D.
25

Secure Mutual Self-Authenticable Mechanism for Wearable Devices

Eya, Nnabuike N., Mapoka, Trust T., Shepherd, Simon J., Abd-Alhameed, Raed, Elfergani, Issa T., Rodriguez, Jonathan 03 1900 (has links)
Yes / Due to the limited communication range of wearable devices, there is the need for wearable devices to communicate amongst themselves, supporting devices and the internet or to the internet. Most wearable devices are not internet enabled and most often need an internet enabled broker device or intermediate device in order to reach the internet. For a secure end to end communication between these devices security measures like authentication must be put in place in other to prevent unauthorised access to information given the sensitivity of the information collected and transmitted. Therefore, there are other existing authentication solutions for wearable devices but these solutions actively involve from time to time the user of the device which is prone to a lot of challenges. As a solution to these challenges, this paper proposes a secure point-to-point Self-authentication mechanism that involves device to device interaction. This work exploits existing standards and framework like NFC, PPP, EAP etc. in other to achieve a device compatible secure authentication protocol amongst wearable device and supporting devices..
26

Caracterização do PolyParaPhenylene (PPP) dopado com FeCl3, utilizando espectroscopia de alta resolução por ressonância magnética nuclear / Characterization of FeCl3-doped PolyParaPhenylene (PPP) using high resolution nuclear magnetic resonance spectroscopy

Giotto, Marcus Vinicius 19 April 1993 (has links)
O objetivo deste trabalho consiste na caracterização do polímero PolyParaPhenylene (PPP) dopado com FeCl3, usando a técnica de Espectroscopia de Alta Resolução em Sólidos por Ressonância Magnética Nuclear. Os espectros de alta resolução de 13C foram obtidos usando, simultaneamente, as técnicas de desacoplamento em alta potencia (DEC) e rotação da amostra em torno do angulo mágico (MASS). Alterações nos espectros de 13C do PPP dopado com FeCl3 causadas por defeitos na cadeia polimérica, tal como polarons e bipolarons, foram analisadas. Efeitos de variação de temperatura e purificação sobre os espectros do PPP, também foram estudados. As amostras foram, adicionalmente, caracterizadas por outras técnicas espectroscópicas, tal como Ressonância Paramagnética Eletrônica (EPR), Efeito Mossbauer, Infra Vermelho e Absorção Atômica; bem como por medidas de Condutividade. Nos observamos que as alterações nas larguras de linha de RMN, estão relacionadas com o aparecimento de bipolarons na cadeia polimérica. / The objective of this work consist of the characterization of FeCl3 doped PolyParaPhenylene (PPP) polymer, using Solid State High Resolution Nuclear Magnetic Resonance Spectroscopy. The 13C high resolution spectra were obtained simultaneously using High Power Decoupling (DEC) and Magic Angle Sample Spinning (MASS) techniques. Alterations in the high resolution 13C spectra of FeCl3 doped PPP caused by defects in the polymer chain such as polarons and bipolarons were analyzed. Effect of temperature variation and purification upon the PPP spectra was also studied. The samples were additionally characterized by others spectroscopic techniques such as Electron Paramagnetic Resonance (EPR), Mossbauer Effect, Infrared and Atomic Absorption as well as by conductivity measurements. We observed that the NMR linewidth changes are related to appearance of the bipolaron in the polymeric chain
27

A regulamentação das parcerias público-privadas (PPP) no Brasil e a experiência do Reino Unido / The public private partnership (PPP) law in Brazil and the United Kingdom´s experience

Archanjo, Paula Fajardo 26 May 2006 (has links)
Made available in DSpace on 2016-04-26T20:48:44Z (GMT). No. of bitstreams: 1 Versao final_pos defesa_27_06.pdf: 756476 bytes, checksum: 6c6d50219d4cb8e8d378535ee87d8bb1 (MD5) Previous issue date: 2006-05-26 / The purpose of this dissertation is to analyse the Public Private Partnership (PPP) law in Brazil in comparison with the United Kingdom s Private Finance Initiative (PFI). The analysis considers the Brazilian federal law and São Paulo and Minas Gerais states law. The first PPP projects (which are in an advanced stage of development) include the construction of a new line in São Paulo s subway system, and the recovery and maintenance of a highway (MG-050) in Minas Gerais. Studying the law is useful for a better understanding of the implementation and operation of future projects in order to provide more effective public infra-structure services and goods. In an atmosphere of fiscal restraint or limited resources, PPP procurement process is an alternative to the provision of public infra-structure services provided by government alone. The analysis of the Brazilian laws incorporates many aspects of British experience, which will be considered as a model in looking at a number of projects and capital involved / A dissertação analisa a regulamentação das parcerias público-privadas no Brasil, as PPP, a partir da experiência do Reino Unido com as iniciativas de financiamento privado, as PFI, equivalente britânico das PPP. A análise considera a Lei federal nº. 11.079 e a legislação estadual de Minas Gerais e de São Paulo, bem como as duas experiências de PPP em fase avançada de preparação no país, a construção da linha 4 do metrô da capital paulista e a recuperação e manutenção da rodovia MG-050 em Minas Gerais. O estudo da legislação se justifica pela relevância dos dispositivos legais para o sucesso das PPP, acordos entre o setor público e o setor privado, em contratos de longo prazo, para a provisão de bens e serviços públicos de infra-estrutura. Premido pela necessidade de viabilizar investimentos em contexto de restrição fiscal, o setor público, em diversos países, encontrou nos arranjos de parceria público-privada o mecanismo alternativo para a provisão de bens e serviços até então de sua responsabilidade exclusiva. A análise da legislação brasileira revela a incorporação de muitos aspectos da experiência britânica, tida como emblemática na área, pelo número de projetos e pelos valores envolvidos
28

Analýza projektů silniční infrastruktury Spolkové republiky Německo / Analysis of road infrastructure projects of the Federal Republic of Germany

Holba, Pavel January 2010 (has links)
The aim of this thesis is to determine the benefits of road infrastructure projects implemented in cooperation between the public and private sectors. The thesis analyses this type of projects that have been realized in Germany. The first chapter briefly characterizes the environment which the projects were implemented in. It also discusses the legislation that governs the issue. On the basis of knowledge obtained from the analysis the projects implemented in cooperation between the public and private sectors are compared with the projects carried out in conventional way. Finally, results are summarized and lead to the conclusion that cooperation between the public and private sector in road infrastructure projects has a future and can be beneficial for other European countries including the Czech Republic.
29

Low-cost GPS/GLONASS Precise Positioning algorithm in Constrained Environment / Algorithme de positionnement précis en environnement contraint basé sur un récepteur bas-coût GPS/GLONASS

Carcanague, Sébastien 26 February 2013 (has links)
Le GNSS (Global Navigation Satellite System), et en particulier sa composante actuelle le système américain GPS et le système russe GLONASS, sont aujourd'hui utilisés pour des applications géodésiques afin d'obtenir un positionnement précis, de l'ordre du centimètre. Cela nécessite un certain nombre de traitements complexes, des équipements coûteux et éventuellement des compléments au sol des systèmes GPS et GLONASS. Ces applications sont aujourd'hui principalement réalisées en environnement « ouvert » et ne peuvent fonctionner en environnement plus contraint. L'augmentation croissante de l'utilisation du GNSS dans des domaines variés va voir émerger de nombreuses applications où le positionnement précis sera requis (par exemple des applications de transport/guidage automatique ou d'aide à la conduite nécessitant des performances importantes en terme de précision mais aussi en terme de confiance dans la position –l'intégrité- et de robustesse et disponibilité). D'autre part, l'arrivée sur le marché de récepteurs bas-coûts (inférieur à 100 euros) capables de poursuivre les signaux provenant de plusieurs constellations et d'en délivrer les mesures brutes laisse entrevoir des avancées importantes en termes de performance et de démocratisation de ces techniques de positionnement précis. Dans le cadre d'un utilisateur routier, l'un des enjeux du positionnement précis pour les années à venir est ainsi d'assurer sa disponibilité en tout terrain, c'est-à-dire dans le plus grand nombre d'environnements possibles, dont les environnements dégradés (végétation dense, environnement urbain, etc.) Dans ce contexte, l'objectif de la thèse a été d'élaborer et d'optimiser des algorithmes de positionnement précis (typiquement basés sur la poursuite de la phase de porteuse des signaux GNSS) afin de prendre en compte les contraintes liées à l'utilisation d'un récepteur bas coût et à l'environnement. En particulier, un logiciel de positionnement précis (RTK) capable de résoudre les ambiguïtés des mesures de phase GPS et GLONASS a été développé. La structure particulière des signaux GLONASS (FDMA) requiert notamment un traitement spécifiques des mesures de phase décrit dans la thèse afin de pouvoir isoler les ambiguïtés de phase en tant qu'entiers. Ce traitement est compliqué par l'utilisation de mesures provenant d'un récepteur bas coût dont les canaux GLONASS ne sont pas calibrés. L'utilisation d'une méthode de calibration des mesures de code et de phase décrite dans la thèse permet de réduire les biais affectant les différentes mesures GLONASS. Il est ainsi démontré que la résolution entière des ambiguïtés de phase GLONASS est possible avec un récepteur bas coût après calibration de celui-ci. La faible qualité des mesures, du fait de l'utilisation d'un récepteur bas coût en milieu dégradé est prise en compte dans le logiciel de positionnement précis en adoptant une pondération des mesures spécifique et des paramètres de validation de l'ambiguïté dépendant de l'environnement. Enfin, une méthode de résolution des sauts de cycle innovante est présentée dans la thèse, afin d'améliorer la continuité de l'estimation des ambiguïtés de phase. Les résultats de 2 campagnes de mesures effectuées sur le périphérique Toulousain et dans le centre-ville de Toulouse ont montré une précision de 1.5m 68% du temps et de 3.5m 95% du temps dans un environnement de type urbain. En milieu semi-urbain type périphérique, cette précision atteint 10cm 68% du temps et 75cm 95% du temps. Finalement, cette thèse démontre la faisabilité d'un système de positionnement précis bas-coût pour un utilisateur routier. / GNSS and particularly GPS and GLONASS systems are currently used in some geodetic applications to obtain a centimeter-level precise position. Such a level of accuracy is obtained by performing complex processing on expensive high-end receivers and antennas, and by using precise corrections. Moreover, these applications are typically performed in clear-sky environments and cannot be applied in constrained environments. The constant improvement in GNSS availability and accuracy should allow the development of various applications in which precise positioning is required, such as automatic people transportation or advanced driver assistance systems. Moreover, the recent release on the market of low-cost receivers capable of delivering raw data from multiple constellations gives a glimpse of the potential improvement and the collapse in prices of precise positioning techniques. However, one of the challenge of road user precise positioning techniques is their availability in all types of environments potentially encountered, notably constrained environments (dense tree canopy, urban environments…). This difficulty is amplified by the use of low-cost receivers and antennas, which potentially deliver lower quality measurements. In this context the goal of this PhD study was to develop a precise positioning algorithm based on code, Doppler and carrier phase measurements from a low-cost receiver, potentially in a constrained environment. In particular, a precise positioning software based on RTK algorithm is described in this PhD study. It is demonstrated that GPS and GLONASS measurements from a low-cost receivers can be used to estimate carrier phase ambiguities as integers. The lower quality of measurements is handled by appropriately weighting and masking measurements, as well as performing an efficient outlier exclusion technique. Finally, an innovative cycle slip resolution technique is proposed. Two measurements campaigns were performed to assess the performance of the proposed algorithm. A horizontal position error 95th percentile of less than 70 centimeters is reached in a beltway environment in both campaigns, whereas a 95th percentile of less than 3.5 meters is reached in urban environment. Therefore, this study demonstrates the possibility of precisely estimating the position of a road user using low-cost hardware.
30

Caracterização do PolyParaPhenylene (PPP) dopado com FeCl3, utilizando espectroscopia de alta resolução por ressonância magnética nuclear / Characterization of FeCl3-doped PolyParaPhenylene (PPP) using high resolution nuclear magnetic resonance spectroscopy

Marcus Vinicius Giotto 19 April 1993 (has links)
O objetivo deste trabalho consiste na caracterização do polímero PolyParaPhenylene (PPP) dopado com FeCl3, usando a técnica de Espectroscopia de Alta Resolução em Sólidos por Ressonância Magnética Nuclear. Os espectros de alta resolução de 13C foram obtidos usando, simultaneamente, as técnicas de desacoplamento em alta potencia (DEC) e rotação da amostra em torno do angulo mágico (MASS). Alterações nos espectros de 13C do PPP dopado com FeCl3 causadas por defeitos na cadeia polimérica, tal como polarons e bipolarons, foram analisadas. Efeitos de variação de temperatura e purificação sobre os espectros do PPP, também foram estudados. As amostras foram, adicionalmente, caracterizadas por outras técnicas espectroscópicas, tal como Ressonância Paramagnética Eletrônica (EPR), Efeito Mossbauer, Infra Vermelho e Absorção Atômica; bem como por medidas de Condutividade. Nos observamos que as alterações nas larguras de linha de RMN, estão relacionadas com o aparecimento de bipolarons na cadeia polimérica. / The objective of this work consist of the characterization of FeCl3 doped PolyParaPhenylene (PPP) polymer, using Solid State High Resolution Nuclear Magnetic Resonance Spectroscopy. The 13C high resolution spectra were obtained simultaneously using High Power Decoupling (DEC) and Magic Angle Sample Spinning (MASS) techniques. Alterations in the high resolution 13C spectra of FeCl3 doped PPP caused by defects in the polymer chain such as polarons and bipolarons were analyzed. Effect of temperature variation and purification upon the PPP spectra was also studied. The samples were additionally characterized by others spectroscopic techniques such as Electron Paramagnetic Resonance (EPR), Mossbauer Effect, Infrared and Atomic Absorption as well as by conductivity measurements. We observed that the NMR linewidth changes are related to appearance of the bipolaron in the polymeric chain

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