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This work investigates processing-microstructure-property relationships of a model cryogenically mechanically alloyed polymer-polymer system: polycarbonate (PC) and poly (ether ether ketone) (PEEK). Mechanically milled and alloyed powders were characterized using a variety of techniques including microscopy and thermal analysis. Cryogenically mechanically alloyed powders processed for 10 hours were shown to have a sub-micron level two-phase microstructure. These powders were processed into testable coupons using a mini ram-injection molder; microstructure and bulk mechanical properties of the coupons were investigated as a function of mechanical alloying and injection molding parameters. Atomic force microscopy, transmission electron microscopy, and scanning transmission X-ray microscopy revealed that the intimate blending achieved during the mechanical alloying process is not retained upon post-processing using a conventional polymer processing technique. Injection molded coupons were tested in 3-point bend mode via dynamic mechanical and quasi-static mechanical testing. Results demonstrated that no improvement in energy to break, strain at failure, or failure strength was achieved in coupons made from cryogenically mechanically alloyed powders compared to those of coupons made from non-mechanically alloyed samples. / Ph. D.

Fiber-optic Bragg grating (FBG) sensors are a very attractive technology for the measurement of strain and temperature. They have many advantages over conventional sensors in sensing applications such as sensitivity, immunity to electromagnetic interferences,large bandwidths,capability of remote operation and the potential power to sense micro strain at high temperature. They can be directly embedded into many structures such as concrete to evaluate the material deformation. FBGs are fabricated by photo-inscribing through a phase mask technology on a photosensitive fiber. A periodic refractive index is formed in the fiber core, introducing a reflection at the Bragg wavelength. Since the FBG is characterized by a low insertion loss and controllable reflectance, it has the potential to be multiplexed in very large numbers. The major purpose of this dissertation research is to develop an innovative, high- resolution fiber Bragg grating sensing system using photon-counting optical time domain reflectometry (pc-OTDR) based multiplexing technology. The system uses a Fresnel reflection OTDR with a zero deadzone to detect FBG sensors, which improves both the system detection ability and spatial resolution. A low reflectance FBG with broad bandwidth has been developed that is appropriate for the pc-OTDR measurement. Hundred of multiplexed sensors have been implemented in this system. Two theoretical analyses and preliminary results are presented. The greatest advantage of the system is to increase the maximum multiplexing sensor number to one thousand within a short fiber range. Self-referencing demodulation is necessary to eliminate multiplexed system noise caused by the source power fluctuation and fiber bending effects. A referencing FBG with a different wavelength from the sensing FBG has to be introduced to achieve compensation of disturbances in the measurement. The spectral properties of the FBGs and the combination of WDM/TDM are also discussed to evaluate multiplexing sensor performance. The sensor crosstalk and other noise performances are assessed to evaluate the possibility of large scale multiplexing. / Ph. D.

A Tablet PC is a portable computing device which combines a regular notebook computer with a digitizing screen that interacts with a complementary electronic pen stylus. The pen allows the user to input data by writing on or by tapping the screen. Like a regular notebook computer, the user can also perform tasks using the mouse and keyboard. A Tablet PC gives the users all the features of a regular notebook computer along with the support to recognize, process, and store electronic/digital ink, enabling a user to make and save hand-written notes or data. In institutions of teaching and learning, instructors often use computer-based materials like web pages, PowerPoint® slides, etc., to explain subject matter. The ability to annotate on presentation information using the electronic stylus of a Tablet PC has attracted the attention of the academic community to use the Tablet PC as a potential tool for increasing the effectiveness of presentations in teaching and learning. Tablet PC-based applications such as OneNote®, WindowsJournal® and Classroom Presenter have been developed to enhance note-taking in classrooms based on the fact that a pen stylus is a more natural form of input device for making notes on the computer as compared to the regular keyboard and mouse. Although tools like OneNote®, WindowsJournal® enhanced the note-taking process on the Tablet PC, they lacked the ability to allow the user to directly annotate on the lecture content. Classroom Presenter provides the ability to integrate classroom notes and the presentation material by allowing the instructors and students to annotate over the lecture material. However, all the above tools lacked the ability to allow a user to take notes over the output window of an arbitrary application like Excel, an active simulator or a movies players output. The Tablet PC based tool, WriteOn, developed at Virginia Tech, addresses this drawback. WriteOn, when deployed on the Tablet PC in a classroom environment, allows the instructor to utilize electronic ink to annotate on top of any application window visible on the Tablet PC display screen, including those that play active content like a movie or simulation. WriteOn facilitates a user to annotate over a dynamic application window by activating its virtual transparency surface called the eVellum (electronic vellum). The user can view a movie or an active simulation running in the eVellum background because of its transparent color. The user can deactivate the eVellum to make it invisible by "piercing" it if he/she wishes to access the desktop or an application window under the vellum window. WriteOn provides the instructor with the ability to broadcast a composite of the dynamic lecture content and ink annotations to the students in real-time. The term dynamic lecture contents is meant to indicate that the content being annotated need not be static words on a background, but may also be window contents that are changing in time. Using WriteOn, the students can make their own notes by writing on the eVellum enabled on top of the lecture stream window without losing visibility of the lecture. The instructor/student can save the ink annotations along with base lecture material as a movie file. The ability of WriteOn to improve classroom presentation and student note-taking as shown by initial tests, were pedagogically very useful. However, in order to deploy WriteOn on large scale in classrooms as an active and effective teaching tool of choice, several aspects of the application had to be improved. One aspect of the application that needed improvement was the user interface. The primitive Graphical User Interface (GUI) of the WriteOn tool was not easily usable by instructors and students from non-computer science backgrounds. The second aspect needing improvement was the operational performance of the application in terms of its CPU resource utilization. The WriteOn tool has shown to have operational performance issues during the screen capture process. This research therefore aims to address improvements in the GUI to make it more user friendly and increase the operational performance to the point where the user does not notice degradation of a base lecture application. Incorporation of these improvements has led us to rename the application as WriteOn1.0. WriteOn1.0 implements a picture-based GUI that comprises of two forms: a main form that appears shortly after WriteOn1.0 starts and a toolbar. The WriteOn1.0 toolbar appears in the center of the top edge of the display as soon as the user initiates a task like a screen recording session, by clicking on the appropriate menu button on the main form. The toolbar provides the user, accessibility to perform all the desired activities like annotating, screen recording, presentation broadcast, and piercing of the eVellum by a single-click of the appropriate menu icon. Tool tips that appear when the user points the mouse over a picture icon on the toolbar, explain the task that shall be performed when he/she clicks on the underlying menu icon. WriteOn1.0 introduces a window-like resizable and movable eVellum called the scalable eVellum that it activates in the area of interest specified by the user. Unlike the first implementation of the eVellum which had a fixed location and spanned the entirety of the user's desktop window, the instructor/student define the dimensions of the scalable eVellum and can choose to re-dimension, relocate and pierce through it at any point of time during a session. WriteOn1.0 also introduces the transparent mode of operation wherein the instructor/student, without having to deactivate the scalable eVellum can access any underlying window by a right-click of the mouse on the eVellum surface while the ink annotations are intact on the foreground. WriteOn1.0 addresses the operational performance issues observed during a screen capture session in WriteOn by capturing the activities only in the area of interest of the user for recording and broadcasting. By combining this scheme with a with a lossless screen capture codec called the MSU screen capture codec that has a high-compression ratio and that is optimized for speed for data compression, WriteOn1.0 greatly improves the operational CPU performance of the tool. WriteOn1.0 employs various technologies to implement its features. The improvements to operational performance are implemented by using the MSU screen codec from Moscow State University's Graphics and Media Lab. Microsoft®'s Video for Windows Framework (VfW) and WindowsMedia Player API's are used to realize the module that records the screen activities to an AVI file while DirectShow of DirectX and ConferenceXP API's are used for streaming presentations over a network. WriteOn1.0, with its features like its scalable eVellum, good operational performance and picture-based GUI is aimed at potentially making it a teaching tool of choice across classrooms and changing the method of classroom instruction of courses involving dynamic content. / Master of Science

This thesis provides an introduction to an advance in technology-aided instruction. Most of the research in this area has focused on PowerPoint® based applications or white board-centered electronic ink applications with the capability of broadcasting slides, ink annotations and so forth, used for presentation or classroom lectures. But these tools lack the capability of annotating on any kind of applications with active content playing (a movie or a simulation, for instance) in the background. Additional useful, but currently unavailable functionality would include the capability of broadcasting the presentation information, which can further consist of lecture slides, ink annotations, video of the desktop screen activity, or any other application program that might be used to demonstrate a concept or illuminate an idea. Therefore, the current research attempts to provide these facilities with a new tool, WriteOn. WriteOn improves both the presentation of information and the interactivity in classroom instruction, because it gives the instructor the ability to ink annotate on any application by using a virtual transparency surface, called electronic vellum or simply eVellum, which in effect resides on top of all desktop window applications. The instructor can enable the vellum at any point during the lecture and write on it to draw diagrams, make notes, emphasize points, or otherwise elucidate the presentation content. The instructor can also pierce the eVellum in order to switch to different applications, modify an applications parameters or operating values, or otherwise manipulate an operating program as part of a classroom demonstration or discussion. These features allow the instructor to demonstrate the dynamic operation of any application, which is an improvement on a static PowerPoint display of a program's operation. With WriteOn, the instructor can save the ink annotations along with desktop screen activity over an interval of time as a movie file and later make this file available to students. Alternatively, the instructor can transmit to the students the presentation information along with ink annotations in real-time so that the students can make their own notes on top of information being produced by the instructor. Thus the tool can be used to enhance the interactive lecturing process and help students to develop good note-taking processes and habits. WriteOn is also capable of saving the voice of the instructor, provided there is an audio device attached to the instructor's Tablet PC. However, broadcasting the instructor's voice is not yet fully supported. The WriteOn tool was developed using Microsoft's technologies: Windows Media Encoder® and DirectShow of DirectX®, as well as Microsoft's ConferenceXP API to achieve streaming of the presentation information. The first chapter explains the need for computer tools used for effective teaching purposes. The second chapter presents the architectural and technical details of WriteOn. Chapter three describes the architecture of the WriteOn tool. Chapters four through six explain the major software components of the system and also give the pros and cons of the DirectShow and Windows Media Encoder technologies. The seventh chapter provides an explanation of the usage of the tool by instructors and students. The eighth chapter presents the experiences of the instructors and students using the WriteOn tool in the classroom and concludes with a discussion of future work in this area. The Appendix V provides a developers guide for those who might like to expand on this open source code. / Master of Science

This thesis describes a performance measurement tool that allows a user to measure network performance using a handheld device. The measurement tool consists of a client program that runs on a Microsoft Pocket PC device and a server program that runs on a regular Microsoft Windows computer. Both programs are Windows applications implemented in C/C++ using the Microsoft Embedded Visual Tool and Microsoft Visual Studio. The use of a Pocket PC device provides mobility to users, which can save time and energy when performing experiments. The thesis describes the design of the performance measurement application, implementation issues, and tests conducted using the tool. / Master of Science

Contexte : Les maladies pulmonaires comme l'asthme ou la mucoviscidose représentent des problèmes majeurs de santé publique. Elles se manifestent par une inflammation chronique avec une production accrue de cytokines pro-inflammatoires et à terme une dégradation de la fonction respiratoire. Les efforts thérapeutiques tentent, d'un côté, de contrôler la réaction inflammatoire et aussi d'améliorer la biodisponibilité médicamenteuse. Objectif : Notre objectif est d'explorer l'implication des phospholipases dans l'inflammation et le rôle des transporteurs peptidiques dans le transport des antibiotiques dans la mucoviscidose. Nous avons aussi cherché à comprendre l'effet d'une supplémentation en cobalamine sur l'efficacité de la dexaméthasone dans un contexte inflammatoire. Méthodes : Des techniques immunologiques, électrophorétiques, de culture cellulaire, d'immunoprécipitation et d'expression génique sont utilisées sur des lignées bronchiques humaines normales ou mucoviscidosiques. Résultats : 1) La PC-PLC est constitutivement suractivée dans les cellules mucoviscidosiques et conduit à une surproduction d'arachidonate, à une surexpression de Cox-2, une surproduction de PGE2, une surexpression d'interleukine-8, et au défaut de régulation beta-adrénergique de la sécrétion. L'inhibition de cette enzyme par le D609 permet de corriger tous ces défauts. 2) L'activité du transporteur peptidique, impliquée dans le transport d'antibiotiques, PEPT2, a été caractérisée dans les cellules bronchiques normales (Vm = 115 pmol/106 cellules/min ; Km = 15µM). Ce transporteur n'est pas influencé par un contexte inflammatoire. Ce transporteur est inactif dans les cellules CF. 3) La cobalamine potentialise l'effet de la déxaméthasone sur la sécrétion et l'expression des cytokines pro-inflammatoires induite par le TNFa et l'histamine. Conclusions/perspectives : Cette étude devrait permettre 1) de mettre en lumière l'importance de la PC-PLC comme cible pharmacologique potentielle dans la mucoviscidose. 2) de comprendre la relative faible efficacité de l'antibiothérapie dans cette maladie et 3) de mettre en évidence une possible participation du cycle de la méthionine dans le processus inflammatoire / Background: Lung diseases such as asthma or cystic fibrosis are major public health problems. They are manifested by chronic inflammation with increased production of proinflammatory cytokines leading to respiratory failure. Current therapeutic is aimed at controling the inflammatory response and also at improving drug bioavailability. Objective: The objective is to explore the involvement of phospholipases in inflammation and the role of peptide transporters in the transport of antibiotics in cystic fibrosis. We also sought to understand the effect of cobalamin supplementation on the effectiveness of dexamethasone in an inflammatory context. Methods: immunological techniques, electrophoresis, cell culture, immunoprecipitation and gene expression are used on normal or cystic fibrosis human bronchial cell lines. Results : 1) PC-PLC is constitutively overactivated in cystic fibrosis cells and leads to overproduction of arachidonate, to overexpression of Cox-2 , an overproduction of PGE2 , an interleukin -8 overexpression , and to alteration of beta-adrenergic secretion. Inhibition of this enzyme by D609 corrects these defects. 2) The activity of the dipeptide carrier involved in the transport of antibiotics, PEPT2, was characterized in normal bronchial cells (Vm = 115 pmol/106 cells / min, Km = 15µM). This transporter is not affected by an inflammatory context. However, it was shown to be inactive in CF cells. 3) Cobalamin potentiates the effect of dexamethasone on the expression and secretion of pro-inflammatory cytokines induced by TNFa and histamine. Conclusions : This study should help 1) to highlight the importance of PC-PLC as a potential pharmacological target in cystic fibrosis. 2) to understand the relative ineffectiveness of antibiotics in this disease , and 3) to highlight a possible involvement of methionine cycle in the inflammatory process

La redistribution temporelle et spatiale des masses environnementales déforment la surface de la Terre. Ces déformations sont observables par des techniques de géodésie spatiale telles que le GNSS. Depuis que les produits d'orbite et d'horloge très précis de l'IGS sont disponibles, que des algorithmes sophistiqués ont été développés, l'iPPP a ouvert une nouvelle ère pour l'analyse du GNSS et pour son application dans les études géophysiques. Ce travail fait partie des premières études pour analyser les différents effets de surcharge, en utilisant des séries temporelles de positionnement, en particulier avec le logiciel GINS-PC et les nouveaux produits d'orbite et d'horloge REPRO2 du GRGS (GR2). Nous visons à exploiter les positions sub-diurnes d'iPPP pour étudier divers effets de déformation de la Terre à différentes échelles de temps: sub-diurne à saisonniers et annuels. Notre objectif est de contribuer à la validation des modèles géophysiques, à l'observation des différents phénomènes non-maréaux, mais aussi de présenter la performance du mode iPPP et du logiciel GINS-PC. Ce dernier est un outil puissant pour les applications géodynamiques, qui permet d'étudier l'influence des effets de surcharge sur l'interprétation géodésique des séries temporelles. Après un aperçu des principales déformations de la surface de la Terre, nous présentons les techniques de géodésie qui ont déjà démontré leur potentiel dans l'analyse de déformation, en particulier dans les études de déformation de surcharge. Nous présentons ensuite la technique de GNSS et le mode de traitement iPPP que nous utilisons pour l'analyse des données. Nous montrons ensuite les résultats de deux études régionales. La première analyse étudie l'influence des effets de surcharge sur la détermination des vitesses tectoniques dans la chaîne des Pyrénées à partir de campagnes GNSS espacées dans le temps. Le deuxième cas d'étude tente de suivre l'évolution spatiale et temporelle des déformations induites par un événement de tempête extrême, à savoir la tempête Xynthia qui a eu lieu en France en 2010. Cette étude tente également d'identifier la réponse dynamique de l'océan pour le système de basse pression atmosphérique se déplaçant rapidement en utilisant des séries temporelles sub-diurnes. Enfin, nous allons vers une étude globale qui pose les bases pour de futures recherches. / The temporal and spatial redistribution of the environmental masses deform the surface of the Earth. These deformations are observable by space geodetic techniques such as GNSS. Since highly accurate IGS satellite and clock data are available and sophisticated algorithms have been developped, the integer fixed ambiguity Precise Point Positioning (iPPP) method opened a new era for the Global Navigation Satellite System (GNSS) analysis and its application in geophysical studies. This work is among the first studies to investigate the different loading effects using iPPP time series, particularly using the GINS-PC software and the new, reprocessed REPRO2 orbit and clock products of GRGS (GR2). We aim to exploit the sub-daily iPPP time series to study various Earth deformation effects at different time scales, from sub-daily to seasonal and annual periods. Our goal is to contribute to the validation of geophysical models, to the observation of the various non-tidal phenomena, as well as the presentation of the performance of the iPPP mode and the GINS-PC package that is a powerful tool for geodynamical applications, and to investigate the influence of the loading effects on geodetic time series interpretation. After an overview of the main deformations of the Earth's surface, we present the geodetic techniques that already demonstrated their potential in deformation analysis, in particular in loading deformation studies. We then review the GNSS technique and the iPPP processing mode as it was our choice for the data analysis. We then demonstrate two regional studies. The first one investigates the influence of the loading effects on GNSS campaign to determine tectonic velocities in the Pyrenees mountain chain. The second case study attempts to track the spatial and temporal evolution of an extreme storm event, the Xynthia windstorm that occured in France, in 2010. This study also tries to identify the ocean's response to the fast moving low pressure system using sub-daily iPPP time series. Finally we go towards a global study which gives base for future research.

台灣記憶體模組產業發展在國內電子產業群聚效應的環境中，初期是令人欽羨的電子新貴事業，產業發展也始終高度依賴個人電腦銷售的特性，讓主要業者在”Wintel”時代享有不錯的成長與獲利。然而在上游記憶體供應業者逐期整併或退出製造，供應面整合漸成寡佔市場，而需求端在經過2008年金融風暴的影響與小筆電對價格的破壞，主要業者近期的經營績效上直接反應這樣的因素影響效應。 　　未來的「後PC時代」是漸進式的發展，由於網路基礎建設的成熟，讓雲端運算的構想得以實現，智慧型手機的發展讓初期應用獲得驗證，2010年Apple推出iPAD產品，業界皆預測個人電腦另一世代變革的來臨，因為iPad的容易使用、個性化的應用與長時效的電力等特點，讓產品的應用範圍擴及多個領域，對手機廠商、傳統電腦業者與潛在的進入者等都是商機的顯現或競爭的威脅。這樣的發展趨勢對記憶體模組業者而言，影響是巨大的，對記憶體IC製造業者可能是銷售的對象或產品的屬性變化，然而對記憶體模組業者則可能是經營模式或競爭態勢的轉變。面對這樣的變革，台灣記憶體模組產業的策略選項將影響業者未來競爭利基點的優劣。 　　「後PC時代」名詞漸被人們所提及，但查詢目前論文或文獻討論等，尚未對此有清楚的描述，更無針對這樣趨勢變化對記憶體模組產業的策略分析。本研究由模組產業形態與「後PC時代」改變的形態的連接，由實務經務的基礎中分析當中的可能策略因應，提供給業者考量未來營運模式組合。