The deployment of dedicated short-range communications (DSRC) roadside units (RSUs) allows a connected or automated vehicle to acquire information from the surrounding environment using vehicle-to-infrastructure (V2I) communication. However, wireless communication using DSRC has shown to exhibit null points, at repeatable distances. The null points are significant and there was unexpected loss in the wireless signal strength along the pathway of the V2I communication. If the wireless connection is poor or non-existent, the V2I safety application will not obtain sufficient data to perform the operation services. In other words, a poor wireless connection between a vehicle and infrastructure (e.g., RSU) could hamper the performance of a safety application. For example, a designer of a V2I safety application may require a minimum rate of data (or packet count) over 1,000 meters to effectively implement a Reduced Speed/Work Zone Warning (RSZW) application. The RSZW safety application is aimed to alert or warn drivers, in a Cooperative Adaptive Cruise Control (CACC) platoon, who are approaching a work zone. Therefore, the packet counts and/or signal strength threshold criterion must be determined by the developer of the V2I safety application. Thus, we selected an arbitrary criterion to develop an empirical method of ascertaining the null points from a DSRC RSU. The research motivation focuses on developing an empirical method of calculating the null points of a DSRC RSU for V2I communication at a highway on/off-ramp. The intent is to improve safety, mobility, and environmental applications since a map of the null points can be plotted against the distance between the DSRC RSU and a vehicle's onboard unit (OBU). The main research question asks: 'What is a more robust empirical method, compared to the horizontal and vertical laws of reflection formula, in determining the null points from a DSRC RSU on a highway on/off ramp?' The research objectives are as follows: 1. Explain where and why null points occur from a DSRC RSU (Chapter 2) 2. Apply the existing horizontal and vertical polarization model and discuss the limitations of the model in a real-world scenario for a DSRC RSU on a highway on/off ramp (Chapter 3 and Appendix A) 3. Introduce an extended horizontal and vertical polarization null point model using empirical data (Chapter 4) 4. Discuss the conclusion, limitations of work, and future research (Chapter 5). The simplest manner to understand where and why null points occur is depicted as two sinusoidal waves: direct and reflective waves (i.e., also known as a two-ray model). The null points for a DSRC RSU occurs because the direct and reflective waves produce a destructive interference (i.e., decrease in signal strength) when they collide. Moreover, the null points can be located using Pythagorean theorem for the direct and reflective waves. Two existing models were leveraged to analyze null points: 1) signal strength loss (i.e., a free space path loss model, or FSPL, in Appendix A) and 2) the existing horizontal and vertical polarization null points from a DSRC RSU. Using empirical data from two different field tests, the existing horizontal and vertical polarization null point model was shown to contain limitations in short distances from the DSRC RSU. Moreover, the existing horizontal and vertical polarization model for null points was extremely challenging to replicate with over 15 DSRC RSU data sets. After calculating the null point for several DSRC RSU heights, the paper noticed a limitation of the existing horizontal and vertical polarization null point model with over 15 DSRC RSU data sets (i.e., the model does not account for null points along the full length of the FSPL model). An extended horizontal and vertical polarization model is proposed that calculates the null point from a DSRC RSU. There are 18 model comparisons of the packet counts and signal strengths at various thresholds as perspective extended horizontal and vertical polarization models. This paper compares the predictive ability of 18 models and measures the fit. Finally, a predication graph is depicted with the neural network's probability profile for packet counts =1 when greater than or equal to 377. Likewise, a python script is provided of the extended horizontal and vertical polarization model in Appendix C. Consequently, the neural network model was applied to 10 different DSRC RSU data sets at 10 unique locations around a circular test track with packet counts ranging from 0 to 11. Neural network models were generated for 10 DSRC RSUs using three thresholds with an objective to compare the predictive ability of each model and measure the fit. Based on 30 models at 10 unique locations, the highest misclassification was 0.1248, while the lowest misclassification was 0.000. There were six RSUs mounted at 3.048 (or 10 feet) from the ground with a misclassification rate that ranged from 0.1248 to 0.0553. Out of 18 models, seven had a misclassification rate greater than 0.110, while the remaining misclassification rates were less than 0.0993. There were four RSUs mounted at 6.096 meters (or 20 feet) from the ground with a misclassification rate that ranged from 0.919 to 0.000. Out of 12 models, four had a misclassification rate greater than 0.0590, while the remaining misclassification rates were less than 0.0412. Finally, there are two major limitations in the research: 1) the most effective key parameter is packet counts, which often require expensive data acquisition equipment to obtain the information and 2) the categorical type (i.e., decision tree, logistic regression, and neural network) will vary based on the packet counts or signal strength threshold that is dictated by the threshold criterion. There are at least two future research areas that correspond to this body of work: 1) there is a need to leverage the extended horizontal and vertical polarization null point model on multiple DSRC RSUs along a highway on/off ramp, and 2) there is a need to apply and validate different electric and magnetic (or propagation) models. / Ph. D. / The deployment of dedicated short-range communications (DSRC) roadside units (RSUs) allows a connected or automated vehicle to acquire information from the surrounding environment using vehicle-to-infrastructure (V2I) communication. However, wireless communication using DSRC has shown to exhibit null points, at repeatable distances. The null points are significant and there was unexpected loss in the wireless signal strength along the pathway of the V2I communication. If the wireless connection is poor or non-existent, the V2I safety application will not obtain sufficient data to perform the operation services. In other words, a poor wireless connection between a vehicle and infrastructure (e.g., RSU) could hamper the performance of a safety application. For example, a designer of a V2I safety application may require a minimum rate of data (or packet count) over 1,000 meters to effectively implement a Reduced Speed/Work Zone Warning (RSZW) application. The RSZW safety application is aimed to alert or warn drivers, in a Cooperative Adaptive Cruise Control (CACC) platoon, who are approaching a work zone. Therefore, the packet counts and/or signal strength threshold criterion must be determined by the developer of the V2I safety application. Thus, we selected an arbitrary criterion to develop an empirical method of ascertaining the null points from a DSRC RSU. The research motivation focuses on developing an empirical method of calculating the null points of a DSRC RSU for V2I communication at a highway on/off-ramp. The intent is to improve safety, mobility, and environmental applications since a map of the null points can be plotted against the distance between the DSRC RSU and a vehicle’s onboard unit (OBU). The main research question asks: “What is a more robust empirical method, compared to the horizontal and vertical laws of reflection formula, in determining the null points from a DSRC RSU on a highway on/off ramp?” The research objectives are as follows: 1. Explain where and why null points occur from a DSRC RSU (Chapter 2) 2. Apply the existing horizontal and vertical polarization model and discuss the limitations of the model in a real-world scenario for a DSRC RSU on a highway on/off ramp (Chapter 3 and Appendix A) 3. Introduce an extended horizontal and vertical polarization null point model using empirical data (Chapter 4) 4. Discuss the conclusion, limitations of work, and future research (Chapter 5). The simplest manner to understand where and why null points occur is depicted as two sinusoidal waves: direct and reflective waves (i.e., also known as a two-ray model). The null points for a DSRC RSU occurs because the direct and reflective waves produce a destructive interference (i.e., decrease in signal strength) when they collide. Moreover, the null points can be located using Pythagorean theorem for the direct and reflective waves. Two existing models were leveraged to analyze null points: 1) signal strength loss (i.e., a free space path loss model, or FSPL, in Appendix A) and 2) the existing horizontal and vertical polarization null points from a DSRC RSU. Using empirical data from two different field tests, the existing horizontal and vertical polarization null point model was shown to contain limitations in short distances from the DSRC RSU. Moreover, the existing horizontal and vertical polarization model for null points was extremely challenging to replicate with over 15 DSRC RSU data sets. After calculating the null point for several DSRC RSU heights, the paper noticed a limitation of the existing horizontal and vertical polarization null point model with over 15 DSRC RSU data sets (i.e., the model does not account for null points along the full length of the FSPL model). An extended horizontal and vertical polarization model is proposed that calculates the null point from a DSRC RSU. There are 18 model comparisons of the packet counts and signal strengths at various thresholds as perspective extended horizontal and vertical polarization models. This paper compares the predictive ability of 18 models and measures the fit. Finally, a predication graph is depicted with the neural network’s probability profile for packet counts =1 when greater than or equal to 377. Likewise, a python script is provided of the extended horizontal and vertical polarization model in Appendix C. Consequently, the neural network model was applied to 10 different DSRC RSU data sets at 10 unique locations around a circular test track with packet counts ranging from 0 to 11. Neural network models were generated for 10 DSRC RSUs using three thresholds with an objective to compare the predictive ability of each model and measure the fit. Based on 30 models at 10 unique locations, the highest misclassification was 0.1248, while the lowest misclassification was 0.000. There were six RSUs mounted at 3.048 (or 10 feet) from the ground with a misclassification rate that ranged from 0.1248 to 0.0553. Out of 18 models, seven had a misclassification rate greater than 0.110, while the remaining misclassification rates were less than 0.0993. There were four RSUs mounted at 6.096 meters (or 20 feet) from the ground with a misclassification rate that ranged from 0.919 to 0.000. Out of 12 models, four had a misclassification rate greater than 0.0590, while the remaining misclassification rates were less than 0.0412. Finally, there are two major limitations in the research: 1) the most effective key parameter is packet counts, which often require expensive data acquisition equipment to obtain the information and 2) the categorical type (i.e., decision tree, logistic regression, and neural network) will vary based on the packet counts or signal strength threshold that is dictated by the threshold criterion. There are at least two future research areas that correspond to this body of work: 1) there is a need to leverage the extended horizontal and vertical polarization null point model on multiple DSRC RSUs along a highway on/off ramp, and 2) there is a need to apply and validate different electric and magnetic (or propagation) models.

Bakgrund: Sjuksköterskestudenter kan genomföra verksamhetsförlagd utbildning inom utbildningsvårdavdelningar. En modell benämns Utvecklande och Lärande Vårdenhet (ULVE), där studenter handleds och vårdar i par. Det finns studier som visar att modellen stödjer studenters lärande, men det finns få studier om hur patienter upplever det att vårdas av studenter i par. Därför är det intressant att undersöka hur patienterna ser på att det är två studenter som vårdar dem och hur de upplever den vård de får. Syfte: Syftet med studien är att beskriva patienters erfarenheter av att vårdas av sjuksköterskestudenter som handleds och vårdar i par. Metod: Studien är genomförd med en reflekterande livsvärldsansats grundad i fenomenologisk kunskapsteori. Fenomenet i studien är ”Att vårdas av sjuksköterskestudenter som vårdar och handleds i par”. Data har samlats in via intervjuer av sjutton patienter som vårdats inom ULVE. Resultat: Att vårdas av studenter som handleds i par innebär att bli involverad i studenternas lärande och att mötas av ansvarstagande och en vilja att vårda och lära.  Patienterna känner trygghet och är positivt inställda till att vårdas av studentpar. Tilltro till att vården ges med stöd av handledning bidrar även till trygghet i vårdsituationen. Resultatet beskrivs vidare med innebördselementen: Involverad i lärande och vårdande, Att vara i centrum för vård, Tilltro och tillit till vårdens kvalitet och Att få något utöver det ”vanliga”. Konklusion: Studien visar att patienter som vårdas av studenter som handleds och vårdar i par sätts i centrum, blir tagna på allvar och lyssnade till som människor. Det visar sig i respektfulla möten som präglas av omtänksamhet, engagemang, närvaro och där behov tillgodoses. Studien stödjer att studenter ger god vård när de handleds och vårdar  i par. / Background: Nursing students can complete clinical training in educational hospital wards. A model called Developing and Learning Care Unit (ULVE), where students care and supports in pair. Studies show that the model supports student learning, but there are few studies about how patients perceive to be cared for by students in pairs. It would be of interest to examine what patient’s experience are, what they think about being cared of students who work in pairs and if they believe that they receive good care.  Aim: The aim of this study is to describe how patients’ experience being cared for by student nurses who are caring and supervised in pairs.     Method: The study was conducted with a reflective lifeworld approach based on phenomenological epistemology. The phenomenon of the study is ”to be cared for by  student nurses caring and supports in pairs”. Data was collected through interviews of seventeen patients cared for  within ULVE.       Results: The care of students who are supported in pairs means to become involved in student learning and to meet the responsibility and a desire to nurture and learn. Patients feel secure and are positive to be looked after by student nurses in pair.  Confidence in the healthcare provided under the supervision also contributes to security in the care situation. The result is further described with four meaningful elements: Being involved  in learning and caring, being the center of care,  confidence and trust in the quality of care and  getting something out of the ”ordinary”. Conclusion: The study showed that patients cared by pairs of students is taken seriously and humanly during supervision of nursing clinician and it focuses in a patient centered care. This method of pair nursing students care shows respect, thoughtfulness, engagement and presence to patients where needs are fulfilled.

Inscrite dans le champ de l'éducation familiale, cette thèse prend appui sur l'histoire de la petite enfance en France, pour en tirer des enseignements sur les organisations et les acteurs, parents et professionnels. Sa perspective est de tracer des pistes d'amélioration du secteur de l'accueil et de l'éducation des jeunes enfants.Par une recherche documentaire, l'approche sociohistorique permet de rapprocher et d'articuler les contextes démographiques et les faits sociaux marquants des différentes époques, depuis le XVIIe siècle, offrant ainsi une continuité aux récits : de la sauvegarde des enfants abandonnés jusqu'aux crèches hygiénistes du XIXe siècle, de l'allaitement mercenaire généralisé au XVIIIe siècle à la diversification des modèles familiaux du siècle dernier, du "sentiment de l'enfance" aux droits de l'enfant devenu "sujet". L'analyse des développements historiques fait émerger une logique dans la construction qualitative des organisations : les initiatives privées sont pérennisées et contrôlées par les autorités publiques, des normes de fonctionnement sont établies sur la base de consensus sociaux.L'histoire révèle aussi les marques des idéologies du passé, chez les professionnels de la petite enfance : sauvegarde charitable, hygiénisme. Enfin, les difficultés des parents de jeunes enfants paraissent récurrentes : isolement, pertes de repères éducatifs. Une expérience de réflexion collective autour de la qualité, d'une part, et une recherche-action locale sur la question de la parentalité, d'autre part, viennent confirmer les enseignements de l'histoire. Dans un contexte actuel qualifié de "managérial", la thèse établit des perspectives d'amélioration qualitative et de soutien à la fonction parentale : démarches curriculaires et participatives, organisation d'espaces de coéducation, comme les Lieux d'Accueil Enfants Parents et autres lieux d'information. / This doctoral thesis, situated in the field of family education, is based on the history of early childhood in France, in order to learn a lesson about the organizations and the protagonists, whether they are parents or professionals. The standpoint of this thesis is to pave the way for improvements in the host sector and in the sector of the education of young children.The sociohistorical approach, by means of a document research, makes it possible to compare and to connect the demographic contexts and the outstanding social facts during the different periods, since the 17th century. Thus this approach offers a continuity for the tales : from the safeguarding of the abandoned children to the hygienist child-care centers of the 19th century, from the paid breast-feeding - which was in general use during the 18th century – to the diversification of the family models during the 20th century, from the « feeling of childhood » to the rights of the child, regarded as a « subject ». The analysis of the historical developments shows a logic in the qualitative construction of the organizations : the private initiatives are perpetuated and controlled by the public authorities, functioning standards - based on social consensus - are promulgated. History also reveals the marks of the former ideologies, among the early childhood professionals : charity safeguarding, hygienism. Finally, the difficulties experienced by young children’s parents seem to be recurrent : isolation, loss of educational benchmarks. An experience of collective thought dedicated to quality, on the one hand, and a local research orientated towards action on the question of parenting, on the other hand, confirm the lessons of history. In a present context that may be described as « managerial », this thesis introduces standpoints for qualitative improvement and for support to the parental function : approaches aiming at a curriculum and participating approaches, organization of spaces making co-education possible – such as the spaces dedicated to host children and parents, and other spaces of information.

O aumento na complexidade das operações de sistemas de produção de petróleo e gás no mar e um fato concreto. Atualmente, a necessidade de avaliar o comportamento no mar destes sistemas requer a compreensão de fenômenos, até então, pouco explorados e que tornam imprescindível uma investigação apoiada em experimentos com modelos reduzidos. Resultados obtidos em tanques de provas, por sua vez, requerem metodologias que contam com a experiência do pesquisador e que, em muitos casos, não são encontradas de maneira detalhada o suficiente na literatura. Ou seja, muitas destas metodologias normalmente são encontradas, no entanto, não em nível para que pesquisadores iniciantes desenvolvam atividades experimentais minimamente pertinentes as eventuais tomadas de decisão ou confrontação com outras linhas de abordagem como a analítica e/ou a numérica. Portanto, e exatamente neste contexto que se insere a presente dissertação de mestrado, buscando descrever em detalhes a teoria e prática envolvida nos procedimentos experimentais para o estudo de comportamento no mar típico de uma plataforma padrão, perfeitamente adaptáveis a outras geometrias mais complexas de sistemas navais e oceânicos. Esses procedimentos envolvem desde o planejamento dos ensaios necessários, passando pelos cuidados durante sua execução, culminando nos métodos de análise dos resultados e formas usuais de documentação. Para facilitar o processo de compreensão, além do próprio texto, este trabalho também contemplou a construção de uma ferramenta matemática dedicada a condução das atividades acima, destacando-se a avaliação e obtenção de parâmetros a partir de ensaios de decaimento e o levantamento expedito das curvas de resposta em ondas regulares, transientes e irregulares. / The increasing complexity of o shore system operations for oil and gas production is a reality. Currently, the need to evaluate the seakeeping of these systems requires understanding some phenomena not yet explored and, for that reason, researches using experiments with small scale models become indispensable. Results obtained in model basins require methodologies that rely on the researchers experience and, most of the time, they are not found detailed enough in the literature. When many of these methodologies are usually found, however, they are not ready for beginner researchers to develop experimental activities minimally relevant to any decision and/or confrontation with other lines, such as the analytical and/or numerical approaches. Therefore, the context of this dissertation describes in detail the theory and involved practice in an experimental procedure for the study of seakeeping of a standard platform, perfectly adaptable to other complex geometries and naval systems. These procedures involve the planning of the necessary tests, through the care during their execution, culminating in the methods of result analyses and usual forms of documentation. In order to facilitate the process of understanding, the construction of a dedicated mathematical tool to conduct the activities described above is provided, emphasizing the assessment and quick obtaining parameters from decay tests, curves response in regular and transient waves, among many others.

L’objectif de cette thèse est de comparer l’efficacité des primes à la suggestion, des primes à la performance, et de la cession de parts aux salariés pour stimuler leur implication dans les dispositifs de suggestion (cercles de qualité, réunions d’atelier, boîtes à idées, etc.). Dans un premier chapitre,sont présentés, une approche historique, un état des lieux et une revue de littérature. Le chapitre suivant pose les jalons d’une théorie, dans un cadre simplifié ne comprenant qu’un employeur et un employé. Il développe un modèle théorique original de la cession de parts, orienté vers les augmentations de capital dédiées aux salariés. Il est montré que, tant que l’employeur n’est pas limité dans le nombre de parts qu’il peut proposer, ce mécanisme est le plus efficace. Le troisième chapitre consolide les résultats du précédent dans un cadre à plusieurs employés. Enfin, le quatrième chapitre présente une étude économétrique à partir de l’enquête REPONSE. La spécification et les variables sont retenues dans le souci d’être au plus proche des modèles théoriques. Les résultats confortent fortement ceux des modèles théoriques élaborés dans les chapitres précédents. / This dissertation aims at comparing the efficiency of suggestion pay, performance pay and shares selling, so as to involve employees into suggestions schemes (e.g. quality circles, workshop meetings, suggestion box). In the first chapter, the historical background, the current situation and the state of literature are being investigated. In the following chapter, a simple framework is considered with only one employer and one employee. A formal model of shared ownership that fits with the French scheme of ’capital increase dedicated to the employees’ is sketched. It is shownthat, as long as the employer is not limited in the number of shares he can offer, the scheme performs better than suggestion pay and performance pay. Next chapter builds upon the previous model and extends the results to a broader framework with multiple employees. The fourth chapter presents an empirical study based on the REPONSE survey. The econometric specification and the variables are chosen to fit the theoretical models. The results strongly support the theory.

The continuous growth of traffic demand driven by the brisk increase in number of Internet users and emerging online services creates new challenges for communication networks. The latest advances in Wavelength Division Multiplexing (WDM) technology make it possible to build Transparent Optical Networks (TONs) which are expected to be able to satisfy this rapidly growing capacity demand. Moreover, with the ability of TONs to transparently carry the optical signal from source to destination, electronic processing of the tremendous amount of data can be avoided and optical-to-electrical-to-optical (O/E/O) conversion at intermediate nodes can be eliminated. Consequently, transparent WDM networks consume relatively low power, compared to their electronic-based IP network counterpart. Furthermore, TONs bring also additional benefits in terms of bit rate, signal format, and protocol transparency. However, the absence of O/E/O processing at intermediate nodes in TONs has also some drawbacks. Without regeneration, the quality of the optical signal transmitted from a source to a destination might be degraded due to the effect of physical-layer impairments induced by the transmission through optical fibers and network components. For this reason, routing approaches specifically tailored to account for the effect of physical-layer impairments are needed to avoid setting up connections that don’t satisfy required signal quality at the receiver. Transparency also makes TONs highly vulnerable to deliberate physical-layer attacks. Malicious attacking signals can cause a severe impact on the traffic and for this reason proactive mechanisms, e.g., network design strategies, able to limit their effect are required. Finally, even though energy consumption of transparent WDM networks is lower than in the case of networks processing the traffic at the nodes in the electronic domain, they have the potential to consume even less power. This can be accomplished by targeting the inefficiencies of the current provisioning strategies applied in WDM networks. The work in this thesis addresses the three important aspects mentioned above. In particular, this thesis focuses on routing and wavelength assignment (RWA) strategies specifically devised to target: (i) the lightpath transmission quality, (ii) the network security (i.e., in terms of vulnerability to physical-layer attacks), and (iii) the reduction of the network energy consumption. Our contributions are summarized below. A number of Impairment Constraint Based Routing (ICBR) algorithms have been proposed in the literature to consider physical-layer impairments during the connection provisioning phase. Their objective is to prevent the selection of optical connections (referred to as lightpaths) with poor signal quality. These ICBR approaches always assign each connection request the least impaired lightpath and support only a single threshold of transmission quality, used for all connection requests. However, next generation networks are expected to support a variety of services with disparate requirements for transmission quality. To address this issue, in this thesis we propose an ICBR algorithm supporting differentiation of services at the Bit Error Rate (BER) level, referred to as ICBR-Diff. Our approach takes into account the effect of physical-layer impairments during the connection provisioning phase where various BER thresholds are considered for accepting/blocking connection requests, depending on the signal quality requirements of the connection requests. We tested the proposed ICBR-Diff approach in different network scenarios, including also a fiber heterogeneity. It is shown that it can achieve a significant improvement of network performance in terms of connection blocking, compared to previously published non-differentiated RWA and ICBR algorithms.  Another important challenge to be considered in TONs is their vulnerability to physical-layer attacks. Deliberate attacking signals, e.g., high-power jamming, can cause severe service disruption or even service denial, due to their ability to propagate in the network. Detecting and locating the source of such attacks is difficult, since monitoring must be done in the optical domain, and it is also very expensive. Several attack-aware RWA algorithms have been proposed in the literature to proactively reduce the disruption caused by high-power jamming attacks. However, even with attack-aware network planning mechanisms, the uncontrollable propagation of the attack still remains an issue. To address this problem, we propose the use of power equalizers inside the network nodes in order to limit the propagation of high-power jamming attacks. Because of the high cost of such equipment, we develop a series of heuristics (incl. Greedy Randomized Adaptive Search Procedure (GRASP)) aiming at minimizing the number of power equalizers needed to reduce the network attack vulnerability to a desired level by optimizing the location of the equalizers. Our simulation results show that the equalizer placement obtained by the proposed GRASP approach allows for 50% reduction of the sites with the power equalizers while offering the same level of attack propagation limitation as it is possible to achieve with all nodes having this additional equipment installed. In turn, this potentially yields a significant cost saving.    Energy consumption in TONs has been the target of several studies focusing on the energy-aware and survivable network design problem for both dedicated and shared path protection. However, survivability and energy efficiency in a dynamic provisioning scenario has not been addressed. To fill this gap, in this thesis we focus on the power consumption of survivable WDM network with dynamically provisioned 1:1 dedicated path protected connections. We first investigate the potential energy savings that are achievable by setting all unused protection resources into a lower-power, stand-by state (or sleep mode) during normal network operations. It is shown that in this way the network power consumption can be significantly reduced. Thus, to optimize the energy savings, we propose and evaluate a series of energy-efficient strategies, specifically tailored around the sleep mode functionality. The performance evaluation results reveal the existence of a trade-off between energy saving and connection blocking. Nonetheless, they also show that with the right provisioning strategy it is possible to save a considerable amount of energy with a negligible impact on the connection blocking probability. In order to evaluate the performance of our proposed ICBR-Diff and energy-aware RWA algorithms, we develop two custom-made discrete-event simulators. In addition, the Matlab program of GRASP approach for power equalization placement problem is implemented. / <p>QC 20120508</p>

The aim of the present thesis is to evaluate fast scintillator materials, in both single-crystal and powder form, for possible usage in dedicated gamma ray imaging applications as well as in X-ray imaging techniques, requiring high frame rates. Powder scintillators are traditionally used in conventional X-ray imaging due to their property to produce high resolution images. This is because laterally directed optical photons, originating from the point of X-ray interaction, are strongly attenuated by light scattering effects on powder grains. This property however is their principal drawback for routine Nuclear Medicine applications. In these applications, photon counting accuracy rather than spatial resolution is required and to this aim high transparency crystals are used. In the present study we have tried to estimate whether the use of powder phosphors can improve the image quality in a dedicated gamma-ray system where spatial resolution than sensitivity is of primary significance. Evaluation was performed in thin and thick phosphor layers easily produced in the laboratory. In addition we present a low cost solution – consisting of a thick continuous powder scintillator screen – for use in dedicated high resolution small gamma imager. The advantages and disadvantages of proposed powder detector performance were compared to two standard 3 x 3 x 5mm3 and 2 x 2 x 3mm3 pixellated CsI:Tl scintillator detector configurations. System performance in terms of system sensitivity, system spatial resolution, energy resolution and linear energy response were measured at energy of 140 keV for close-proximity nuclear emission imaging. All measurements were carried out in photon counting mode in planar imaging configuration. The investigation was divided into two parts: Fast powder scintillators: In this part, powder scintillator screens of LSO:Ce, YAG:Ce and GOS:Pr were prepared in various coating thicknesses. Measurements concerning determination of emission spectra and absolute luminescence efficiency were carried out under X-ray excitation from 22 to 140 kV. Related parameters giving informations on luminescence and intrinsic properties of the phosphors such as X-ray luminescence efficiency, quantum detection efficiency, energy absorption efficiency and intrinsic conversion efficiency were also examined. Low cost and high resolution detector module: The goal of this part was to propose and evaluate a low cost solution for detector module – consisting of a thick continuous powder scintillator screen – for use in dedicated high resolution small gamma imagers. For the latter purpose, we examined the performance of the aforementioned fast powder scintillators in the form of thick screens easily produced in the laboratory. System performance in terms of system sensitivity, system spatial resolution, energy resolution and linear energy response were measured and compared for two standard 3 x 3 x 5mm3 and 2 x 2 x 3mm3 pixellated CsI:Tl. / Ο σκοπός της παρούσας διατριβής είναι η αποτίμηση φθοριζόντων υλικών υψηλής απόκρισης, τόσο σε κρυσταλλική όσο και σε κοκκώδη μορφή για πιθανή χρησιμοποίησή τους σε συγκεκριμένους τύπους ανιχνευτικών συστημάτων Πυρηνικής Ιατρικής όπως επίσης σε συστήματα απεικόνισης με ακτίνες Χ που απαιτούν πολύ γρήγορες λήψεις ιατρικής εικόνας. Τα φθορίζοντα υλικά κοκκώδους μορφής χρησιμοποιούνται ευρύτατα στην απεικόνιση με ακτίνες-Χ λόγω της υψηλής διακριτικής ικανότητας που μπορεί να επιτευχθεί. Στην παρούσα διατριβή μελετήθηκε κατά πόσο η χρήση νέων, γρήγορων φθοριζόντων υλικών κοκκώδους μορφής μπορεί να βελτιώσει την απόδοση συγκεκριμένων τύπων ανιχνευτικών συστημάτων Πυρηνικής Ιατρικής (π.χ. dedicated small nuclear imagers), στα οποία η διακριτική ικανότητα του συστήματος είναι πιο σημαντική από την ευαισθησία. Η αποτίμηση έγινε σε φθορίζοντα μεγάλου πάχους που παρασκευάστηκαν στο εργαστήριο. Επιπρόσθετα στην παρούσα διατριβή παρουσιάζεται η εφαρμογή ενός χαμηλού κόστους συμπαγούς ανιχνευτικού υλικού κοκκώδους μορφής σε ένα εξειδικευμένο σύστημα Πυρηνικής Ιατρικής. Γίνεται συστηματική μελέτη και εκτενής αναφορά στα πλεονεκτήματα και τα μειονεκτήματα αυτού του συστήματος. Τα αποτελέσματα συγκρίνονται με αντίστοιχα αποτελέσματα που ελήφθησαν με χρήση διακριτοποιημένων σπινθηριστών τύπου CsI:Tl, μεγέθους 3 x 3 x 5mm3 και 2 x 2 x 3 mm3. Η απόδοση του συστήματος ως προς την ευαισθησία (sensitivity), τη χωρική διακριτική ικανότητα (spatial resolution) και την ενεργειακή διακριτική ικανότητα (energy resolution) αποτιμήθηκε για ενέργεια 140 keV, που αντιστοιχεί στην ενέργεια του ισοτόπου 99mTc που χρησιμοποιείται ευρύτατα σε εξετάσεις Πυρηνικής Ιατρικής. Η πειραματική μελέτη χωρίστηκε σε δύο μέρη: Φθορίζοντα υλικά κοκκώδους μορφής: Στο πρώτο μέρος της παρούσας διδακτορικής διατριβής μελετήθηκαν τα φθορίζοντα υλικά κοκκώδους μορφής LSO:Ce, YAG:Ce και GOS:Pr σε διάφορα πάχη και για μεγάλη κλίμακα ενεργειών (Υψηλή τάση λυχνίας ακτίνων-Χ από 22 kV έως 140 kV). Ανιχνευτής χαμηλού κόστους και υψηλής διακριτικής ικανότητας: Ο τελικός στόχος της παρούσας διατριβής ήταν η κατασκευή ενός ενιαίου ανιχνευτή, βασισμένου σε σπινθηριστή κοκκώδους μορφής, χαμηλού κόστους και υψηλής διακριτικής ικανότητας, κατάλληλου για χρήση σε εξειδικευμένα συστήματα Πυρηνικής Ιατρικής. Για το σκοπό αυτό μελετήθηκε η συμπεριφορά των υλικών κοκκώδους μορφής LSO:Ce, YAG:Ce και GOS:Pr υπό διέγερση ακτίνων γάμμα με ισότοπο Τεχνητίου (99mTc), ενέργειας 140 keV, που χρησιμοποιείται ευρύτατα στην Πυρηνική Ιατρική. Τα υλικά αυτά υπό την μορφή ενιαίου, μεγάλου πάχους ( ≥2mm) και διαμέτρου (9 cm), συμπαγούς ανιχνευτή αξιολογήθηκαν με τεχνικές απεικόνισης μονού φωτονίου (single photon counting mode).

O aumento na complexidade das operações de sistemas de produção de petróleo e gás no mar e um fato concreto. Atualmente, a necessidade de avaliar o comportamento no mar destes sistemas requer a compreensão de fenômenos, até então, pouco explorados e que tornam imprescindível uma investigação apoiada em experimentos com modelos reduzidos. Resultados obtidos em tanques de provas, por sua vez, requerem metodologias que contam com a experiência do pesquisador e que, em muitos casos, não são encontradas de maneira detalhada o suficiente na literatura. Ou seja, muitas destas metodologias normalmente são encontradas, no entanto, não em nível para que pesquisadores iniciantes desenvolvam atividades experimentais minimamente pertinentes as eventuais tomadas de decisão ou confrontação com outras linhas de abordagem como a analítica e/ou a numérica. Portanto, e exatamente neste contexto que se insere a presente dissertação de mestrado, buscando descrever em detalhes a teoria e prática envolvida nos procedimentos experimentais para o estudo de comportamento no mar típico de uma plataforma padrão, perfeitamente adaptáveis a outras geometrias mais complexas de sistemas navais e oceânicos. Esses procedimentos envolvem desde o planejamento dos ensaios necessários, passando pelos cuidados durante sua execução, culminando nos métodos de análise dos resultados e formas usuais de documentação. Para facilitar o processo de compreensão, além do próprio texto, este trabalho também contemplou a construção de uma ferramenta matemática dedicada a condução das atividades acima, destacando-se a avaliação e obtenção de parâmetros a partir de ensaios de decaimento e o levantamento expedito das curvas de resposta em ondas regulares, transientes e irregulares. / The increasing complexity of o shore system operations for oil and gas production is a reality. Currently, the need to evaluate the seakeeping of these systems requires understanding some phenomena not yet explored and, for that reason, researches using experiments with small scale models become indispensable. Results obtained in model basins require methodologies that rely on the researchers experience and, most of the time, they are not found detailed enough in the literature. When many of these methodologies are usually found, however, they are not ready for beginner researchers to develop experimental activities minimally relevant to any decision and/or confrontation with other lines, such as the analytical and/or numerical approaches. Therefore, the context of this dissertation describes in detail the theory and involved practice in an experimental procedure for the study of seakeeping of a standard platform, perfectly adaptable to other complex geometries and naval systems. These procedures involve the planning of the necessary tests, through the care during their execution, culminating in the methods of result analyses and usual forms of documentation. In order to facilitate the process of understanding, the construction of a dedicated mathematical tool to conduct the activities described above is provided, emphasizing the assessment and quick obtaining parameters from decay tests, curves response in regular and transient waves, among many others.

This thesis is focused on construction of device for inpection of final casting for machine casting dedicated for tension of car cam belt. Device for inpection of final casting is operated by pneumatic parts and is intended to check operational parts of the machine casting. Control is designed directly to enterprise production. It is constructed according to the custom requirements and it’s operability was confirmed on a prototype. It’s construction solves the problems with manual checking. General analysis of machine cast checking as well as analysis of machine casting dedicated for tension of car cam belt in the submitting company is included in the thesis. Moreover, the thesis comprises of discussion of the construction itself, discussion of pneumatic operating elements and economical and technological review.

Agile software development methods keep increasing in popularity. Many organizations who are using traditional software development methods, such as water-fall and stagegate based methods are switching to agile software development methods. This transition can be challenging, especially for organizations using project governance models that hinder the adoption of agile practices. This study aims to provide guidance to managers on how to introduce agile software development methods in such traditional organizations. The study is a single-case study on a large governmental agency in Sweden. Eight interviews with developers, team-leads and managers were conducted. The study identifies practical tools and ideas that managers can use to introduce a shared definition of agile, adopting an agile mindset, dedicated teams, and CI&amp;CD. Together, this guidance supports managers with the introduction of agile software development methods in organizations utilizing traditional project governance structures and traditional software development methods. / Agila systemutvecklingsmetoder fortsätter öka i popularitet. Många organisationer som använder sig av traditionella systemutvecklingsmetoder så som vattenfallsmodellen byter till agila systemutvecklingsmetoder. Denna övergång kan vara utmanande, speciellt för organisationer som använder sig av projektbaserade förvaltningsmodeller som hindrar implementeringen av agila metoder. Den här studien syftar till att ge vägledningen till chefer kring hur de kan introducera agila systemutvecklingsmetoder iden nyss nämnda typen av traditionella organisationer. Studien är en fallstudie gjort på en stor myndighet i Sverige. Åtta intervjuer med systemutvecklare, lag-ledare och chefer har utförts. Studien identifierar verktyg och idéer som chefer kan använda sig avför att introducera en delad gemensam definition av agilt, anamma ett agilt tankesätt, introducera dedikerade teams och CI&amp;CD. Tillsammans hjälper de här verktygen med introduktionen av agila systemutvecklingsmetoder i organisationer som använder sig av traditionella systemutvecklingsmetoder och förvaltningsmodeller.