Les ``C-arm'' sont des systémes de radiologie interventionnelle fréquemment utilisés en salle d'opération ou au lit du patient. Des images 3D des structures anatomiques internes peuvent être calculées à partir de multiples radiographies acquises sur un ``C-arm mobile'' et isocentrique décrivant une trajectoire généralement circulaire autour du patient. Pour cela, la géométrie conique d'acquisition de chaque radiographie doit être précisément connue. Malheureusement, les C-arm se déforment en général au cours de la trajectoire. De plus leur motorisation engendre des oscillations non reproductibles. Ils doivent donc être calibrés au cours de l'acquisition. Ma thèse concerne la calibration intrinsèque d'un C-arm à partir de la détection de la projection du collimateur de la source dans les radiographies.Nous avons développé une méthode de détection de la projection des bords linéaires du collimateur. Elle surpasse les méthodes classiques comme le filtre de Canny sur données simulées ou réelles. La précision que nous obtenons sur l'angle et la position (phi,s) des droites est de l'ordre de: phi{RMS}=+/- 0.0045 degrees et s{RMS}=+/- 1.67 pixels. Nous avons évalué nos méthodes et les avons comparés à des méthodes classiques de calibration dans le cadre de la reconstruction 3D. / Mobile isocentric x-ray C-arm systems are an imaging tool used during a variety of interventional and image guided procedures. Three-dimensional images can be produced from multiple projection images of a patient or object as the C-arm rotates around the isocenter provided the C-arm geometry is known. Due to gravity affects and mechanical instabilities the C-arm source and detector geometry undergo significant non-ideal and possibly non reproducible deformation which requires a process of geometric calibration. This research investigates the use of the projection of the slightly closed x-ray tube collimator edges in the image field of view to provide the online intrinsic calibration of C-arm systems.A method of thick straight edge detection has been developed which outperforms the commonly used Canny filter edge detection technique in both simulation and real data investigations. This edge detection technique has exhibited excellent precision in detection of the edge angles and positions, (phi,s), in the presence of simulated C-arm deformation and image noise: phi{RMS} = +/- 0.0045 degrees and s{RMS} = +/- 1.67 pixels. Following this, the C-arm intrinsic calibration, by means of accurate edge detection, has been evaluated in the framework of 3D image reconstruction.

在考量或依據籌措資金的目的、資金成本、募集資金的金額、貨幣市場及法令因素等，公司會在多元的籌資管道中選擇最有利的方式進行。可轉換公司債自民國79年遠東紡織發行後，就受到企業的喜愛與投資人的注意。發行可轉換公司債時機及營運績效與發行CB之相關性，是本研究所探討的重點，同時也希望此研究結果能對未來預發行可轉換公司債的企業有所幫助。 本研究首先透過問卷調查的方式，發現企業發行國內可轉換公司債之主要動機為募資資金成本較低，選擇發行ECB的主要動機則為降低利息負擔。接著嘗試已證實測試方式，依照所選取樣本分成四組，進行對照比較，發現外部因素如利率、股價、法令變動對企業是否選擇CB作為募資方式並無明顯相關性。再進一步了解發行CB對公司營運績效影響，發現公司發行可轉換公司債之後，獲利變差。另外進行公司特徵之分析；在鋼鐵業方面，發行前財務比率即較同業差，發行年度及發行後二年財務比率並未因發行可轉換公司債而轉好，因此無法推估發行可轉換公司債與獲利能力之關聯性。在電子業方面；三組電子業的樣本與同業的對照比較中，以半導體產業發行可轉換公司債為募資方式的公司最多，且發行後可能公司本身獲利能力有逐漸衰退，但無論是獲利能力，經營能力等財務比率皆優於同業。 遂進一步觀察其發行時機集中在86、87年，正處於半導體景氣衰退期，直到89年初景氣才復甦，正發揮可轉換公司債的產品特色，在景氣衰退時，以發行可轉換公司債的利息負擔最低，可在獲利減少下避免稀釋盈餘，且可以高於市場價格作為轉換價格，避免股價的低估，或許這是被認為發行可轉換公司債後，獲利能力會變差的原因之一，但半導體廠商在選對正確時機發行後，在景氣不佳時，仍有優於同業的獲利及經營能利，實則為發行可轉換公司債所帶來的最低成本的資金。 關鍵字：可轉換公司債、海外可轉換公司債、營運績效、CB、ECB / To consider or base on the purpose of financing、the cost of capital、the amount of fund、currentfinancial market conditions and governing laws.....etc,usually a company will choose the most beneficial source of finance. In 1990 in Taiwan, the Convertible Bond ( CB ) was issued by Far East Textile Co. and was favorably attracted by both companies and investors since. The primary subject of this studding is to discuss the correlation between the time of issuing CB and operating performance after issuing CB. Hopefully, this paper can be useful to the company desiring to issue CB in the future. First o fall, by using the survey method I found that most companies in Taiwan chose issuing local CB as the source of finance because of cheaper capital cost. Some companies chose issuing ECB for reducing interest burden. Secondly, by using practical test method: separate the selected samples into four groups for comparison testing. In results, there is no obvious correlation between exterior factors and the companies whether issuing CB. The exterior factors include interest、stock price and security laws. Finally, this paper explains the operating performance, especially the earning profit ability, of the companies getting poor after issuing CB. To understand such result, compare the characteristics of the companies in the same industry. In steel and iron industry；the financial ratios of the selected company without issuing CB are poorer than competitors’. Then the selected company didn't get better within two years after issuing CB. In this case, I can't assume that the operating performance or result is related to the company issuing CB matter. In electronic industry; three samples of electronic corporations were compared with their competitors. This paper illustrates that issuing CB as the way of financing for the company is the most popular among semiconductor industry. Although the selected company faced a downturn in earnings after issuing CB, it still performed well in terms of financial ratios compared with its competitors. To go a step further to observe the issuing time during 1997 and 1998, the semiconductor industry encountered a slumped condition until early 2000. In this time frame, CB product naturally explained its merits by itself. When the company faced a down-turn economic situation, usually with poor earnings,the company tended to issue CB as the source of finance in order to reducing interest cost, smoothing earning per share, protecting shareholders' rights to transfer a better share price in the future. The condition above accidentally misled the thoughts of that the issue of CB will cause poor earnings. The companies in semiconductor industry chose the right time to issue CB.They still keep a better operating performance than competitors and obtain fund for the lowest cost of capital due to choose issuing CB as the way of finance.

No description available.

Monitoring of abnormal events in a distribution feeder by using a single technique is a challenging task. Many abnormal events can cause unsafe operation, including a high impedance fault (HIF) caused by a downed conductor touch ground surface, an incipient fault (IF) caused by partial breakdown to a cable insulation, and a circuit breaker (CB) malfunction due to capacitor bank de-energization to cause current restrikes. These abnormal events are not detectable by conventional protection schemes. In this dissertation, a new technique to identify distribution feeder events is proposed based on the complex Morlet wavelet (CMW) and on a decision tree (DT) classifier. First, the event is detected using CMW. Subsequently, a DT using event signatures classifies the event as normal operation, continuous and non-continuous arcing events (C.A.E. and N.C.A.E.). Additional information from the supervisory control and data acquisition (SCADA) can be used to precisely identify the event. The proposed method is meticulously tested on the IEEE 13- and IEEE 34-bus systems and has shown to correctly classify those events. Furthermore, the proposed method is capable of detecting very high impedance incipient faults (IFs) and CB restrikes at the substation level with relatively short detection time. The proposed method uses only current measurements at a low sampling rate of 1440 Hz yielding an improvement of existing methods that require much higher sampling rates.

This thesis represents the most detailed investigation into English royal funeral ceremonies 1570-1625 yet undertaken. It builds on earlier scholarship dealing with the French royal funeral and with the social history of death and burial in early modern England. When gathering my source material I consulted manuscript and early printed material at the British Library, the Bodleian Library, the Library of Westminster Abbey, the College of Arms and the Bibliothèque Nationale. My approach is to consider royal funeral rituals in terms of performance. I endeavour to place each of the royal funerals in its immediate performance and broader cultural context. The evidence is analysed using an approach which seeks to take account of both the political and affective implications of ritual. Preliminary chapters establish the form of the English heraldic funeral and the French royal funeral, and assess the impact of the English Reformation on funeral ritual. I go on to discuss the funerals of Mary Stuart, Elizabeth I, Prince Henry Stuart, Anne of Denmark and James I respectively. Included is a bridging chapter which briefly summarises the religious and cultural changes which took place under James I and their impact on funeral ritual. Royal funerals are seen as flexible rather than fixed. They were modified to meet changing political needs but such modifications were always in accord with broader cultural trends. My thesis demonstrates that royal funeral rituals were highly dependent on their performance and cultural contexts. The Epilogue looks at the implications my research has for readings of stage representations of funeral ritual and funeral symbolism in Elizabethan and Jacobean drama. I show that royal funerals formed an important aspect of playhouse audience experience. Dramatists exploited that experience to show the operative nature of funeral ritual performance and the potency of its symbols for political propaganda.

La cellulose bactérienne (CB) est bien connue pour sa biocompatibilité, moulabilité, pureté et cristallinité ainsi que pour sa structure fibrilleuse nanométrique. Cependant, la production des matériaux par des microorganismes est innovante. La présente thèse initialise ce type de bioproduction dans nos laboratoires. Les bactéries productives de cellulose sont isolées à partir d'un vinaigre Libanais. Plusieurs études cinétiques sont établies. Les isolats sont étudiés dans différents milieux de cultures en variant la source de carbone et la température d'incubation, pour déterminer les conditions optimales recommandées pour la production de meilleurs rendements de CB. La bactérie productive de CB a été étudiée en détails au niveau de son cycle de vie et phases de croissance. La physiologie des cellules a été clarifiée et les mécanismes qui précédent et qui accompagnent la synthèse de CB ont été expliqués. Un modèle mathématique se basant sur l'équation logistique est employé pour standardiser les paramètres étudiés. Le rendement de CB a été accru en appliquant différents chocs aux cellules. Le choc thermique appliqué pendant les étapes précoces d'incubation ainsi que le choc acide ont montré des résultats innovants et accéléré le métabolisme de synthèse de CB. L'aspect environnemental du travail a été valorisé en préparant un milieu de culture extraits des fruits et légumes endommagés. En termes d'application, la CB a été utilisée pour produire des papiers et des papiers résistants à l'eau et comme additive dans un prototype d'industrie de papier. Ainsi des composites de cellulose/Liquides ioniques ont été produits afin de performer des matériaux à haute constante diélectriques / Bacterial cellulose (BC) is a wellknown polymer of this family. Its main attractive properties are the biocompatibility, moldability, purity, crystallinity and fibrillar structure at the nanoscaled level. The production of such materials by microorganisms is an innovative procedure. In order to trigger this production procedure in our laboratories, the present thesis was the preliminary step to go through this huge micro-world. In the first step, we isolated cellulose producers from Lebanese vinegar. Kinetic studies were established to clarify the profile of the producer and to optimize cellulose production. The isolates were studied under different incubation temperatures in different microbiological media and at different carbon sources levels to determine optimal conditions for BC production. In the second step, cellulose producer was studied concerning bacterial phases and life cycles. Cells physiologies were clarified and mechanisms that accompany cellulose formation on the top of cultures were discussed. A mathematical model was set basing on Logistic equation to standardize the parameters. Then, cellulose yield was enhanced by different cells choc methods. Thermal choc was applied on cultures during earlier stages of incubation. Moreover, acids were used as doping agents to the culture media. In parallel, to satisfy the eco-friendly aspect of the work, bacterial cellulose production was optimized using fruits and vegetables wastes juice. Papers and waterproof papers were produced using BC. BC was also used as an additive in industrial paper making and was found to enhance mechanical resistance of the papers. In addition, a high-K material was performed using bacterial cellulose and ionic liquids

No description available.

No description available.

The interactions which occur between both polar and non-polar fluid phases and surfaces of various carbon materials: Activated Carbon (AC), non-porous Carbon Black (CB) and Multiwall Carbon Nanotubes (MWCNTs)with different surface chemistry have been studied. These are currently of great interest as they govern the interfacial behaviour of carbons in a wide range of applications; separation adn composite technologies being two prime examples. Consequently, techniques for chemical modification of carbon surfaces ar also of interest. Surface oxygen functional groups have been introduced, or modified, using the following oxidation techniques: liquid-phase oxidation (both AC and CB), Fenton and Birch reduction treatment (MWCNTs) and in a more controlled manner using gas-phase ozone treatment (CB). The chemistry of all the resulting carbon surfaces were characterised using X-ray Photoelectron Spectroscopy (XPS), which gives a quick and direct quantitative measure of the external surface composition. This technique, which has not yet been extensively employed in detailed adsorption studies, is a promising alternative to Temperature Programmed Desorption (TPD) and Boehm titration method in the determination of oxygen and other surface groups. Physical effects of the various surface modifications have been studied using a variety of techniques appropriate for the material in question. Scanning Electron Microscopy (SEM) images show some deteriorating effects of the liquid-phase oxidations on the structure of both activated carbon and carbon black materials. Conversely, surface areas from nitrogen adsorption at 77oK, coupled witj immersion calorimetry data for toluene, show thet the physical structure of the carbon blacks is not modified by ozone treatment. This has allowed a detailed study of the effects of surface oxygen level (i.e. polarity) on vapour adsorption. Regarding the MWCNT materials, detailed High-Resolution Electron Microscopy (HRTEM) photographs show that the multi-wall structure of the nanotubes in not significantly disrupted during the introduction of active functional groups by the Fenton or Birch treatment and therefore keeping intact their mechanical properties which augurs well for their use as reinforcement in composite structures whilst also improving their dispersion properties in polar fluids. A systematic shift to higher adsorption values, due to the increasing specific interactions between the alcohol -OH groups and the surface oxygen groups, is observed in all the isotherms of alcohols from the CB series as the total surface oxygen concentration ([O]T) increases. Moreover, this effect was observed to be most significant for methanol confirming that the mechanism of adsorption is dominated by hydrogen bonding and therefore dependant on the surface concentration of oxygen sites; whereas it becomes less marked in the case of ethanol and isopropanol respectively due to the increasing non-specific, dispersion, interactions of the alkyl chain with the non-polar carbon surface. Overall correlations were observed between the surface oxygen concentration [O]T, the resulting enthalpy of immersion -^Hi values and the characteristic energy E of the Dubinin-Radushkevich-Kaganer (DRK) equation obtained for toluene and these alcohols and the influence of the carbon surface chemistry on the character of the adsorption isotherms is also discussed. This behaviour is also observed and much more pronounced in the case of water adsorption on other oxidised carbon materials (AC, CB and MWCNT) due to the higher polarity of water molecules. The water adsorption data were analysed using in particular the Dubinin-Serpinsky (DS) equation and also some of its recent variations such as Barton and D'Arcy & Watt equations. The DS2 and various Barton equations were found to fit best the AC and CB materials modified by liquid-phase oxidations and also for the CB 03 series with increasing level of oxidation while both D'Arcy & Watt equations gave the best fittings for the MWCNTs materials. It was also shown that the resulting parameters ao (for the DS equation) describing the surface concentration of primary polar adsorption sites and as the limiting water adsorption value were both linked to the surface oxygen level [O]T. Regarding interfacial bonding, the oxidised CB and MWCNT materials are expected to show an improved physicochemical wetting of their surfaces by various resin compunds

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