Typescript (photocopy). / Digitized by Kansas Correctional Industries

As a nonwetting liquid is forced to invade the cavities of nanoporous materials, the liquid-solid interfacial tension and the internal friction over the ultra-large specific surface area (usually billions of times larger than that of bulk materials) can lead to a nanoporous energy absorption system (or, composite) of unprecedented performance. Meanwhile, while functional liquids, e.g. electrolytes, are confined inside the nanopores, impressive mechanical-to-electrical and thermal-to-electrical effects have been demonstrated, thus making the nanoporous composite a promising candidate for harvesting/scavenging energy from various environmental energy sources, including low grade heat, vibrations, and human motion. Moreover, by taking advantage of the inverse process of the energy absorption/harvesting, thermally/electrically controllable actuators can be designed with simultaneous volume memory characteristics and large mechanical energy output. In light of all these attractive functionalities, the nanoporous composite becomes a very promising building block for developing the next-generation multifunctional (self-powered, protective and adaptive) structures and systems, with wide potential consumer, military, and national security applications. In essence, all the functionalities of the proposed nanofluidic energy conversion system are governed by nanofluidics , namely, the behavior of liquid molecules and ions when confined in ultra-small nanopores. Nanofluidics is an emerging research frontier where solid mechanics and fluid mechanics meet at the nanoscale. The complex interactions between liquid molecules/ions and solid atoms at the nanointerface, as well as the unique structural, thermal and electrical characteristics of fluids confined in nanocavities collectively represent an outstanding challenge in physical science. A thorough understanding of the science of nanofluids, in particular the detailed molecular mechanisms as well as the roles of various material and system parameters, does not only underpin the development and optimization of the aforementioned nanofluidic energy conversion system, but it also have broad impact on a number of other areas including environmental engineering, chemical engineering, bioengineering, and energy engineering, etc. This dissertation carries out a systematic computational study to explore the fundamental nanofluidic infiltration and transport mechanisms, as well as the thermal and electrical characteristics of the solid-liquid interface. New physical models describing the unique nanofluidic phenomena will be established, where critical parameters, such as the surface tension, contact angle, and viscosity, will be reinvestigated at the nanoscale. The effects of various material and system parameters, such as the solid phase, liquid phase, pore size and pore geometry, as well as the external thermal, electrical and mechanical loads, etc., will be systematically investigated and bridged with the nanofluidic energy conversion processes. The energy conversion efficiencies under various conditions will be evaluated via a synergy between simulation and experiment. Reverse analysis based on the revealed principles can guide the optimization of the various material and system parameters, which potentially may contribute to the design of highly efficient and sustainable nanofluidic energy conversion devices. Besides the direct impact on the nanofluidic energy conversion, the study is also directly relevant to biological conduction and environmental sustainability, in both of which infiltration and transport play important roles.

陸文雪. / 論文(哲學博士)--香港中文大學, 2003. / 參考文獻 (p. 228-236). / 中英文摘要. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Lu Wenxue. / Zhong Ying wen zhai yao. / Lun wen (zhe xue bo shi)--Xianggang Zhong wen da xue, 2003. / Can kao wen xian (p. 228-236).

On s'intéresse à la localisation des sources normales et pathologiques de l'activité cérébrale électrique chez le nouveau-né et l'enfant prématuré à partir de mesures en Electro-Encéphalo-Graphie (EEG). La spécificité chez le nouveau-né est la présence, dans la couche du crâne, des fontanelles qui ont des propriétés électriques différentes de celles de l'os. Du point de vue mathématique, le problème direct en EEG consiste à calculer le potentiel électrique sur le scalp connaissant la géométrie de la tête, les conductivités de différents tissus de la tête et les caractéristiques des sources de courant localisées à l'intérieur du cerveau. Le problème inverse de sources en EEG vise à identifier les caractéristiques des sources de courant à partir de mesures du potentiel électrique enregistrées sur le scalp. Nous proposons dans cette thèse un modèle mathématique du problème direct chez le nouveau-né capable de prendre en compte la présence et l'ossification des fontanelles. L'analyse théorique et numérique des problèmes direct et inverse sont traitées et une discussion sur l'impact des fontanelles est effectuée. En outre, une étude de la sensibilité des mesures du potentiel par rapport à la variation de la conductivité est réalisée / We investigate the localization of the normal and pathological sources of electric cerebral activity in neonates from measures in Electro-Encephalo-Graphy (EEG). The specificity for neonates is the presence of fontanels in the skull. Mathematically, the forward EEG problem consists in computing the electric potential on scalp for given electrical source located in the brain and different head tissues’ conductivities. The inverse EEG source problem is identifying the characteristics of sources of current from the knowledge of the measured potentials on scalp by EEG. We propose in this thesis a mathematical model for the forward EEG problem in neonates able to take into account the presence and ossification process of fontanels. We perform the theoretical and numerical questions for the forward and inverse problems and discuss the impact of fontanels. We perform a sensitivity analysis of the model with respect to variations of the conductivity

This thesis explores the perception of the emperor in the mentalités of his subjects, exploring the different ways he was understood. Drawing upon written material from Augustus to Alexander Severus, this thesis explores the roles he was cast in, alluding to a discourse concerning who the emperor was and what he should be, exploring similarities across the period. It is argued the participants in this conversation are not restricted to an elite, but also involved scrutiny from a wider population. Accordingly, this thesis is an alternative history about how the Emperor seemed. It is split into three parts according to episodes of an emperor's life: Part 1 and Chapter 1 explore the nature of the succession, including a discussion of the scholarship concerning the nature of the emperor's power and its transmission. It explores the nature of the succession, the imperial family, and perception of this issue from the perspective of his subjects. Part 2 explores the discourse about the emperor's conduct during his reign. Chapter 2 discusses the issues with the evidence, and how to glean a wider perspective. Chapter 3 is a thematic treatment of the 'topics of conversation' within the discourse, and each help to describe the 'thought-world' concerning the emperor, involving the fears and expectations of his roles in government, culture, and society; from the banal to the fantastic. Part 3 and Chapter 4 concern the emperor's legacy. It discusses the impression of the emperor's timelessness, and the comparability of the emperorship. This is reflected in the afterlife of an emperor, showing the relevancy of dead emperors to subsequent generations, and is manifested in diverse ways, from historical discourse to the appearance of false emperors. Finally, comparability is stressed, opening possibilities for further study on the nature of the emperorship as an example of autocracy.

>Magister Scientiae - MSc / The late- to post-collisional Cape Granite Suite (CGS) located in the southwest of South Africa is comprised of S-, I-, and A-type granites, mafic intrusives, and volcanic flows. The CGS is interpreted to have formed during the closing of the Adamastor Ocean during the Late-Proterozoic to Early-Cambrian. Recently, the S-type granites have received much attention concerning their petrogenesis and sources. However, the I- and A-type granites remain poorly understood and little studied. Therefore, with new geochemical and isotopic data the petrogenesis, sources, and tectonic settings of I- (Vredenburg Batholith) and A-type (Cape Columbine) granites of the CGS form the focus for this study. The major and trace element data presented in this thesis show that the granites from the Vredenburg Batholith are weakly peraluminous to metaluminous, ferroan, and alkali-calcic. Associated with the granites are metaluminous, magnesian, and calc-alkalic igneous enclaves. Formerly, the granites have been interpreted to have formed by fractionation. However, with new geochemical analyses and reassessment of such models, it can be shown that such processes are incompatible with accounting for the chemical variation displayed by the granites and their enclaves. Moreover, the I-type granites and enclaves exhibit positive linear trends between whole-rock major and trace elements vs. maficity (Fe + Mg), which can be explained by co-entrainment of peritectic and accessory phases. The lithogeochemical characteristics of the enclaves and host granite reflect melting of a heterogeneous source. Moreover, the granite and enclave"s ?Nd(t) values reflect melting of Paleoproterozoic-aged crustal sources. Finally, with tectonomagmatic discrimination diagrams, it can be shown that the tectonic setting of the granites indicates a transition from a collisional to extensional regime which corroborates the inferences of previous studies. The Cape Columbine Granites lithogeochemical characteristics are ferroan, calc-alkalic and weakly peraluminous. They show typical A-type granite characteristics in having high silica content, high Na + K values, REE enrichment as compared to S- and I-type granites and strong negative Eu anomalies. For this thesis, it can be shown that anatexis of quartzofeldspathic protolith in an extensional regime produced the chemical variation of the Cape Columbine Granite. Moreover, their isotope ratios are typically radiogenic, indicative of a crustal origin. With this new geochemical data evidence is provided against and in support of previous inferences made about the petrogenesis of the I- and A-type granites of the CGS. This also betters our understanding of the magmatic processes involved in the construction of the CGS over time.

A vinhaça da cana-de-açúcar constitui-se no principal resíduo líquido gerado pelo setor sucro-alcooleiro e, face aos enormes volumes produzidos , os problemas decorrentes de seu armazenamento e disposição o final passaram a constituir nos últimos tempos num grande desafio a técnicos envolvidos com essa questão. Este estudo tem por objetivo apresentar uma alternativa de aproveitamento desse resíduo, Aquelas tradicionalmente conhecidas no meio alcooleiro, por .intermédio do tratamento e transformação da vinhaça em biogás e sua utilização na geração de eletricidade. Para tanto, adotou-se a tecnologia de digestão anaeróbia de alta eficiência através de digestores de fluxo ascendente para a produção de biogás e, uma vez purificado, o aproveitamento desse gás em motores e turbinas adequadas a esse tipo de combustíve1, conforme a literatura consultada. No sentido de avaliar a viabilidade prática deste trabalho, optou-se pela elaboração de um estudo de caso, no qual foi dimensionada uma destilaria hipotética de \'cerca de 150.000 litros de álcool/dia, gerando um volume de cerca de 1.800.000 litros de vinhaça/dia. Por meio desta simulação, foram analisados os aspéctos técnicos e econômicos envolvidos, possibilitando assim, uma apreciação crítica e realista do estudo proposto. / The vinasse of sugar-cane represents the main liquid residue produced by the sugar-alcohol sector and, in view of the enormous volumes produced, the problems related to its storage and final disposal came to pose a great challenge to the technical people involved in this matter these last few years. This study aims to present an alternative for the exploitation of this residue, to these traditionally employed in the alcohol production industry, based on the treatment and transformation of vinasse to biogas, and its subsequent utilization in eletric generation. In this context the technology of high efficiency anaerobic digestion using up-flow anaerobic digestors for biogas production was adapted. Once purified, the biogas produced can be utilized in engines and turbines specially adapted for this fuel, as evinced in the literature consulted. With a view to evaluate the pratical feasibility of this work, the elaboration of a case study was selected, in which a hypothetical distillery with a capacity of about 150.000 litres of alcohol/day, would generate a volume of about 1.800.000 litres of vinasse/day. By means of this simulation, the technical and economic aspects involved were analyzed, thus making possible a critical and realistic appreciation of the study proposed.

acase@tulane.edu / 1 / Qi Li

This thesis provides an overview of work conducted to investigate human spatial hearing in situations involving multiple concurrent sound sources. Much is known about spatial hearing with single sound sources, including the acoustic cues to source location and the accuracy of localisation under different conditions. However, more recently interest has grown in the behaviour of listeners in more complex environments. Concurrent sound sources pose a particularly difficult problem for the auditory system, as their identities and locations must be extracted from a common set of sensory receptors and shared computational machinery. It is clear that humans have a rich perception of their auditory world, but just how concurrent sounds are processed, and how accurately, are issues that are poorly understood. This work attempts to fill a gap in our understanding by systematically examining spatial resolution with multiple sound sources. A series of psychophysical experiments was conducted on listeners with normal hearing to measure performance in spatial localisation and discrimination tasks involving more than one source. The general approach was to present sources that overlapped in both frequency and time in order to observe performance in the most challenging of situations. Furthermore, the role of two primary sets of location cues in concurrent source listening was probed by examining performance in different spatial dimensions. The binaural cues arise due to the separation of the two ears, and provide information about the lateral position of sound sources. The spectral cues result from location-dependent filtering by the head and pinnae, and allow vertical and front-rear auditory discrimination. Two sets of experiments are described that employed relatively simple broadband noise stimuli. In the first of these, two-point discrimination thresholds were measured using simultaneous noise bursts. It was found that the pair could be resolved only if a binaural difference was present; spectral cues did not appear to be sufficient. In the second set of experiments, the two stimuli were made distinguishable on the basis of their temporal envelopes, and the localisation of a designated target source was directly examined. Remarkably robust localisation was observed, despite the simultaneous masker, and both binaural and spectral cues appeared to be of use in this case. Small but persistent errors were observed, which in the lateral dimension represented a systematic shift away from the location of the masker. The errors can be explained by interference in the processing of the different location cues. Overall these experiments demonstrated that the spatial perception of concurrent sound sources is highly dependent on stimulus characteristics and configurations. This suggests that the underlying spatial representations are limited by the accuracy with which acoustic spatial cues can be extracted from a mixed signal. Three sets of experiments are then described that examined spatial performance with speech, a complex natural sound. The first measured how well speech is localised in isolation. This work demonstrated that speech contains high-frequency energy that is essential for accurate three-dimensional localisation. In the second set of experiments, spatial resolution for concurrent monosyllabic words was examined using similar approaches to those used for the concurrent noise experiments. It was found that resolution for concurrent speech stimuli was similar to resolution for concurrent noise stimuli. Importantly, listeners were limited in their ability to concurrently process the location-dependent spectral cues associated with two brief speech sources. In the final set of experiments, the role of spatial hearing was examined in a more relevant setting containing concurrent streams of sentence speech. It has long been known that binaural differences can aid segregation and enhance selective attention in such situations. The results presented here confirmed this finding and extended it to show that the spectral cues associated with different locations can also contribute. As a whole, this work provides an in-depth examination of spatial performance in concurrent source situations and delineates some of the limitations of this process. In general, spatial accuracy with concurrent sources is poorer than with single sound sources, as both binaural and spectral cues are subject to interference. Nonetheless, binaural cues are quite robust for representing concurrent source locations, and spectral cues can enhance spatial listening in many situations. The findings also highlight the intricate relationship that exists between spatial hearing, auditory object processing, and the allocation of attention in complex environments.

<p><p>In this study we have investigated the news interview both from the perspective of the journalists and of the subjects of the interview.</p><p>We have made interviews with 50 persons who participated as sources in the news and with 21 journalist who wrote the articles in the local newspapers Östran and Barometern in Kalmar, the 21 of November 2008.</p><p>The journalists were asked to tell their story of how the articles where produced, how they prepared before the interviews, if they had an image of the articles in advance and if they were satisfied with the outcome of the article. The persons who had been interviewed were asked to tell us how they felt about the interviews, if they were satisfied with the outcome of the article, if they could consider being in the newspaper again and to give their opinion of local journalism.</p><p>Most of the persons who had been quoted in the articles said that at least one or two things went wrong in the articles. Despite this they would not hesitate to be interviewed the newspaper again.</p><p>Surprising for us was to see how often the journalists get “served” with both the news and the subjects of the interview. It was for an example often that the Journalists visited press conferences and wrote articles from press releases. When the journalists produced news in this way, they simply interviewed those present at the press conference or the contact person in the press release</p></p>