Thesis (M.S.)--University of Michigan, 1993.

Thesis (M.S.)--University of Michigan, 1993.

Στην παρούσα διπλωματική εργασία πραγματοποιήθηκε επεξεργασία και ανάλυση δεδομένων που συλλέχθηκαν κατά την περίοδο μελέτης της περιοχής της Στούπας στην Νοτιοανατολική Μεσσηνία, στον όρμο της Καλόγριας, με απώτερο στόχο την διερεύνηση του φαινομένου των υποθαλάσσιων εκροών υπογείων υδάτων. / --

Eigenmannia virescens is a gymnotiform weakly electric fish which uses a quasi-sinusoidal electric organ discharge (EOD) to sense their environment. EOD frequency (EODF) is individual-specific. In conspecific interactions, each fish perceives the EODF of the conspecific as a periodic amplitude modulation (AM) of their own discharge. When both fish are stationary, the depth of this AM is constant, but it varies when fish are swimming. We hypothesized that AM variations during swimming act as a noise source that could have no effect on, hinder, or enhance EODF identification. To test this, we quantified the jamming avoidance response (JAR) (a natural behaviour wherein fish are required to accurately determine one another’s EODF) in response to stimuli of varying depths of noise. These experiments demonstrated that swimming noise does not impair the ability of E. virescens to identify conspecific EODF, and actually improves its ability to detect the presence of a neighbouring fish.

This thesis decribes insolvency proceeding, primarily obligation and rights of creditor while information is baded on the Law no 182/2006 Coll., Insolvency Law. There is created instruction that should be used by creditor during insolvency proceeding. Thereafter there is in the part "practise" presented and analysed specific real case, this case was figured out by audition.

Made available in DSpace on 2014-06-11T19:25:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-08Bitstream added on 2014-06-13T20:14:00Z : No. of bitstreams: 1 santos_alr_me_guara.pdf: 967831 bytes, checksum: 8cbbf37b87afd6e4a7c7ecc3380f9ebf (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Materiais poliméricos têm sido amplamente utilizados em várias áreas tecnológicas e biomédicas, devido às suas excelentes propriedades mecânicas, térmicas e elétricas. No entanto, estes materiais têm baixa energia de superfície e, portanto, não aderem facilmente a outros materiais. Por isso, para muitas aplicações é necessário modificar a superfície do polímero, a fim de aumentar a sua energia de superfície. Tratamentos a plasma à pressão atmosférica têm sido muito utilizados para modificar as propriedades superficiais de polímeros comerciais, devido aos baixos custos do processo. Este trabalho apresenta os resultados do tratamento de tereftalato de polietileno (PET), poliuretano (PU) e de politetrafluoretileno (PTFE) em plasma de descargas com barreira dielétrica (DBD) em ar, nitrogênio e argônio, à pressão atmosférica. As superfícies tratadas foram caracterizadas por medidas de ângulo de contato, espectroscopia de fotoelétrons de raios-X (XPS) e microscopia de força atômica (AFM). A superfície polimérica, modificada nas DBD a pressão atmosférica, mostraram uma redução significativa no ângulo de contato da água, embora uma recuperação parcial da molhabilidade ocorresse nos primeiros dias após o tratamento. Todavia, a recuperação foi insuficiente para que as amostras tratadas recuperassem a sua molhabilidade original. Análises de XPS mostraram um aumento na concentração de oxigênio na superfície, devido à formação de grupos polares, tais como C-O e OC= O. Um pequeno aumento na concentração de nitrogênio também foi observada. Imagens de AFM mostraram um aumento da rugosidade de polímeros tratados, decorrentes da interação física entre as espécies geradas na descarga e a superfície do polímero. A superfície ativada e a elevada tensão superficial dos polímeros tratados devem levar a um aumento da aderência do polímero. / Polymeric materials have been widely used in various biomedical and technological applications, due to their excellent mechanical, thermal and electric properties. However, these materials have low surface energy, and thus not easily adhere to other materials. Therefore, for many applications it is necessary to modify the polymer surface in order to increase its surface energy. Plasma treatments at atmospheric pressure have been frequently used to modify the surface properties of commercial polymers, due to their low process costs. This work reports the results of polyethylene terephthalate (PET), polyurethane (PU) and polytetrafluoroethylene (PTFE) treatments in plasma by dielectric barrier discharges (DBDs) in air, nitrogen and argon at atmospheric pressure. The plasma-modified surfaces were characterized by contact angle measurements, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The polymer surface, modified by DBD at atmospheric pressure, showed a significant decrease in water contact angle although a partial recovery of the surface wettability occurred during the first few days after the treatment. However, the process of hydrophobic recovery was insufficient for complete recovering of the samples original wettability. XPS analysis showed an increase of the oxygen concentration on the surface, due to the formation of polar groups, such as C-O and OC= O. A small increase in the concentration of nitrogen was also observed. AFM images exhibit an increased roughness of the treated polymers because of the physical interaction between the species generated in the discharge and the polymer surface. The activated surface and high surface tension of treated polymers should promote an enhancement of the polymer adhesion to paints and coatings.

This Master Thesis work cover the simulation of the movement of charged species exposed to a high gradient electric field, the same environment a plasma actuator produces. The final goal is to use the plasma actuator as an active flow control device to decrease the drag of a body moving in air. This report describes how the problem was set up in COMSOL Multiphysics and the resulting volume force achieved. The volume force is the force generated by the plasma actuator that is acting on the air. To understand the effect of a plasma actuator better experimental work was also performed. The experimental work include what effect a plasma actuator has on a wing that has stalled out and measuring the air velocity obtained from a single plasma actuator. The conclusion is that more work has to be performed to make the plasma actuator a more effective flow control device. This type of work is a way to understand how plasma actuators work and in extension will lead to how a plasma actuator will be used effectively. / Detta examensarbete behandlar simuleringen om hur laddade partiklar rör sig när de utsätts för ett elektriskt fält med hög gradient, ett liknande närområde som skapas av en plasma aktuator. Slutmålet är att kunna använda plasma aktuatorer som en aktiv flödeskontroll med avsikt att minimera motsåndet på en stelkropp som rör sig genom luften. Den här rapporten beskriver hur problemet ställs upp i COMSOL Multiphysics och vilken volymkraft som fås utav simulerignen. Volymkraften är den genererade kraft från plasma aktuatorn som aggerar på den omgivande luften. Utöver simuleringen har praktiska experiment gjorts för att förstå effekten från en plasma aktuator bättre. Dessa experiment består av hur en plasma aktuator förändrar luftströmmen över en vinge som redan tappat sin lyftkraft och av att mäta vilken hastighet luften kan nå på grund av en plasma aktuator. Sammanfattnignen är att mer arbete behöver göras för att effektivisera en plasma aktuator om den ska användas för flödeskontrol. Detta arbeta är ett steg i att förstå hur plasma aktuatorer fungerar vilket i förlängningen kommer leda till hur man ska använda en plasma aktuator på bästa sätt.

This thesis explores the role of the nurse on an Acute Medical Admissions Unit (AMAU). AMAUs provide a dedicated area for the assessment, treatment, and subsequent transfer or discharge of patients who are medical emergencies. Despite increasing numbers of AMAUs across the UK they are an under researched area and, in particular, there is limited research that has explored the role of the nurse in the AMAU setting. Data were generated through the use of ethnography that entailed participant observation over an eighteen-month period, semi-structured interviews with a purposive sample of doctors, nurses, paramedics, and patients (n= 19), and examination of documentary evidence. Drawing on the concept of communities of practice (Wenger 1998) and the demand-control-social support model of occupational stress (Baker et al., 1996) the key themes of the study were identified as: The AMAU nurse's role in co-ordinating patients ' transition; Professional skills and attributes o f the AMAU nurse; 7 love the buzz': the AMAU nurses' work place stresses and balances; and Organisational constraints and practice boundaries for AMA U nursing The findings from the study indicate that a key aspect of the AMAU nurse's role was the facilitation of rapid patient transition. In addition the study has identified the distinctive and locally negotiated working practices developed by the nurses to coordinate this transition. Another important claim arising from this study was the identification of this nursing role as an evolved construction within a community of practice. This study makes a significant contribution to the limited body of knowledge regarding AMAU nursing practice by aiding understanding of the complexity of this nursing role. Additionally, the application of the concept of community of practice provides a unique perspective and insight into this under explored role. Recommendations are offered for practice, education, management and future research.

La protection contre les décharges électrostatiques (ESD) est un fait necessaire dans chaque circuit intégré. Elle se fait par le déploiement sur la puce d'un réseau de dispositifs spéciaux, à côtés des éléments fonctionnels. La demande pour des améliorations en continu dans la conception et la simulation de l'ESD apporte le besoin de modèles nouveaux et plus précises. La SCR (« Silicon Controlled Rectifier ») est l'un des dispositifs les plus efficaces de protection contre l'ESD. Un nouveau modèle électrique, qui peut être utilisé pour évaluer les structures de protection complexe dont il fait partie, a été développé au cours de cette thèse. Construit avec une forte relation entre les phénomènes physiques et ses équations, il a été parametrisé geometriquement, offrant la possibilité d'adapter et d'optimiser le dispositif selon le niveau de protection nécessaire. Par ailleurs, une étude à haute fréquence sur le SCR et la diode de protection ESD a été réalisé, conduisant à un modèle capable de prédire l'impact de ces dispositifs ont sur le circuit protégé. / Electrostatic discharge (ESD) protection is a must in every integrated circuit. It is done by deploying a network of special devices on-chip, alongside the functional elements. The demand for continuously improvements in ESD design and simulations brings the need of new and more accurate scalable models. The SCR (silicon controlled rectifier) is one of the most efficient ESD protection devices. A new electrical model, that can be used to evaluate the complex protection structures of which it is part of, was developed during this thesis. Built with a strong relation between the physical phenomena and its equations, it was rendered scalable, offering the possibility of tailoring and optimizing the device according to the needed protection level. Moreover, a high-frequency study on the SCR and the ESD protection diode was carried out, leading to a model able to predict the impact these devices have on the protected circuit.

Orientador: Nilson Cristino da Cruz / Banca: Sandro Donnini Mancini / Banca: Mauricio Antonio Algatti / O Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi da Unesp / Resumo: O avanço tecnológico obtido através dos tempos permitiu o surgimento de uma nova classe de materiais, os biomateriais, cujas funções principais são o auxilio ou a substituição de partes do corpo humano. Para a fabricação de próteses e/ou implantes podem ser utilizados os polímeros. A utilização de tais dispositivos médicos pode ocasionar o surgimento de alguns problemas, como a incompatibilidade da prótese com o organismo e a contaminação por bactérias, sendo o último um problema grave, podendo ser fatal. A contaminação por Pseudomonas aeruginosa e Staphylococcus aureus pode causar graves infecções. Uma das formas de se resolver este problema é através do tratamento de superfícies, pois a adesão das bactérias é dependente das propriedades superficiais dos biomateriais. Uma técnica de tratamento superficial bastante promissora é o tratamento a plasma de descarga luminescente. Foram realizados tratamentos de superfícies em poliuretano e silicone utilizando plasmas de 'SF IND. 6' com diferentes condições de tratamento, com o objetivo de se conseguir superfícies hidrofóbicas e a não adesão de microrganismos nessas superfícies. Após o tratamento as amostras foram contaminadas com as bactérias S. aureus e P. aeruginosa. Observou-se que embora o tratamento a plasma tenha conferido comportamento hidrofóbico aos polímeros, ainda não conseguiu-se chegar a superfícies ideais para inibir a adesão de microrganismos. / Abstract: The technological advance attained through time, allowed the appearance of a new class of materials, the biomaterials, which main functions are: to help or to replace parts or sick organs of the human body. For the manufacture of prosthesis and/or implants, polymers can be used as biomaterials. The use of prosthesis or implants may cause the appearance of some problems, such as the incompatibility between the prosthesis and the organism and the contamination caused by bacteria. This last one is a serious problem, since it may lead to death. The contamination by Pseudomonas aeruginosa and Staphylococcus aureus can cause serious infections. One possible way to solve this problem is through the surface treatment, since the adhesion of the bacteria depends on the superficial properties of the biomaterial. A promising technique of superficial modification is the treatment through glow discharge plasma. In this work, polyurethane and silicone coupons were exposed to 'SF IND. 6' glow discharge plasmas with different conditions of treatment. After the treatment, the coupons were contaminated with the P. aeruginosa e S. aureus. Even though the plasma treatment gives a hydrophobic behavior to the polymer, it can't obtain the ideal surfaces who inhibit the bacterial adhesion. / Mestre