Title from PDF of title page. / Document formatted into pages; contains 76 pages. / Thesis (M.S.E.E.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: The use of digitized information is rapidly gaining acceptance in bio-medical applications. Video compression plays an important role in the archiving and transmission of different digital diagnostic modalities. The present scheme of video compression for low bit-rate networks is not suitable for medical video sequences. The instability is the result of block artifacts resulting from the block based DCT coefficient quantization. The possibility of applying deformable motion estimation techniques to make the video compression standard (H.263) more adaptable for bio-medial applications was studied in detail. The study on the network characteristics and the behavior of various congestion control mechanisms was used to analyze the complete characteristics of existing low bit rate video compression algorithms. The study was conducted in three phases. The first phase involved the implementation and study of the present H.263 compression standard and its limitations. / ABSTRACT: The second phase dealt with the analysis of an external force for active contours which was used to obtain estimates for deformable objects. The external force, which is termed Gradient Vector Flow (GVF), was computed as a diffusion of the gradient vectors associated with a gray-level or binary edge map derived from the image. The mathematical aspect of a multi-scale framework based on a medial representation for the segmentation and shape characterization of anatomical objects in medical imagery was derived in detail. The medial representations were based on a hierarchical representation of linked figural models such as protrusions, indentations, neighboring figures and included figures--which represented solid regions and their boundaries. The third phase dealt with the vital parameters for effective video streaming over the internet in the bottleneck bandwidth, which gives the upper limit for the speed of data delivery from one end point to the other in a network. / ABSTRACT: If a codec attempts to send data beyond this limit, all packets above the limit will be lost. On the other hand, sending under this limit will clearly result in suboptimal video quality. During this phase the packet-drop-rate (PDR) performance of TCP(1/2) was investigated in conjunction with a few representative TCP-friendly congestion control protocols (CCP). The CCPs were TCP(1/256), SQRT(1/256) and TFRC (256), with and without self clocking. The CCPs were studied when subjected to an abrupt reduction in the available bandwidth. Additionally, the investigation studied the effect on the drop rates of TCP-Compatible algorithms by changing the queuing scheme from Random Early Detection (RED) to DropTail. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.

Σκοπός της εργασίας αυτής είναι η ανάλυση του νέου νομικού καθεστώτος διαχείρισης και ελέγχου των χημικών ουσιών σε ευρωπαϊκό επίπεδο και η ανάδειξη των ποικίλων διακυβευμάτων που αυτό θέτει. Το νέο αυτό νομικό καθεστώς, παρά την μακροχρόνια διαβούλευση του, δεν είναι τελικά απαλλαγμένο από αδυναμίες και προβλήματα εφαρμογής. Πρόκειται για τον νέο κανονισμό REACH (αρχικά του Registration, Evaluation and Authorisation of Chemicals) ή κανονισμό 1907/2006/ΕΚ. Ο κανονισμός REACH αποτελεί ένα ενιαίο ευρωπαϊκό νομοθέτημα για την καταχώριση, την αξιολόγηση, την αδειοδότηση και τους περιορισμούς των χημικών ουσιών, αντικαθιστώντας 40 διαφορετικά υφιστάμενα νομοθετικά μέτρα. Η εργασία χωρίζεται στην εισαγωγή, σε έξι κεφάλαια και τέλος τα συμπεράσματα. Στην εισαγωγή παρουσιάζεται η υφιστάμενη νομοθεσία της ευρωπαϊκής ένωσης για τις χημικές ουσίες, τα προβλήματα από την εφαρμογή της καθώς και η ανάγκη για ένα νέο νομοθετικό πλαίσιο το οποίο θα αντικαταστήσει το υφιστάμενο και θα έχει ως πρωταρχικό σκοπό την προστασία της ανθρώπινης υγείας και του περιβάλλοντος. Αναφορά γίνεται στην βιώσιμη ανάπτυξη και την πράσινη χημεία, καθώς αποτελούν βασικούς πυλώνες του κανονισμού. Επίσης παρουσιάζονται οι βασικές αρχές του κανονισμού (αρχή της προφύλαξης, της υποκατάστασης κλπ) καθώς και οι επιδιωκόμενοι στόχοι από την εφαρμογή του. Στο πρώτο κεφάλαιο γίνεται μια αναλυτική παρουσίαση της αρχής της προφύλαξης, η οποία αποτελεί βασική και θεμελιώδης αρχή του κανονισμού. Γίνεται αναφορά στην σχέση της με την αρχή της πρόληψης, στην πορεία της μέσα στο ευρωπαϊκό δίκαιο και στη διατροφική πολιτική της ευρωπαϊκής ένωσης καθώς και η αντιμετώπισή της από το ελληνικό δικαιικό σύστημα. Στο δεύτερο κεφάλαιο παρουσιάζεται αναλυτικά η οικοδόμηση του κανονισμού REACH, μέσω των σημαντικότερων χρονολογικών γεγονότων που άλλοτε ενίσχυσαν και άλλοτε αποδυνάμωσαν το κανονισμό, ικανοποιώντας κάθε φορά και διαφορετικά συμφέροντα ή απαιτήσεις, έως την οριστικοποίηση του τελικού του κειμένου. Ειδική αναφορά γίνεται στο ρόλο του Παγκόσμιου Οργανισμού Εμπορίου για τη διαμόρφωση του τελικού κειμένου του κανονισμού. Στη συνέχεια, στο τρίτο κεφάλαιο, παρουσιάζονται αναλυτικά το πεδίο εφαρμογής του κανονισμού, τα θεσμικά όργανα και οι αρμοδιότητές τους καθώς και οι βασικές διατάξεις του κανονισμού, η καταχώριση, η αξιολόγηση, η αδειοδότηση και περιορισμοί των χημικών ουσιών. Ακολουθεί το τέταρτο κεφάλαιο, όπου παρουσιάζεται ο κανονισμός CLP (αρχικά του Classification, Labelling, Packaging) για την ταξινόμηση, την επισήμανση και συσκευασία χημικών ουσιών και μειγμάτων ή κανονισμός 1272/2008/EK. Ο κανονισμός CLP συμπληρώνει και τροποποιεί τον κανονισμό REACH στο κενό που παρουσιάζει όσον αφορά την ταξινόμηση, την σήμανση και τη συσκευασία των χημικών ουσιών και τον εναρμονίζει με το Παγκόσμιο Εναρμονισμένο Σύστημα ταξινόμησης και επισήμανσης για τις χημικές ουσίες και τα μείγματα των Ηνωμένων Εθνών. Στο πέμπτο κεφάλαιο γίνεται μια αναλυτική αποτίμηση του κανονισμού REACH, καθώς παρουσιάζονται και αναλύονται τόσο οι θετικές του όψεις όσο και οι αδυναμίες του. Αναλυτική αναφορά γίνεται στο κόστος εφαρμογής του κανονισμού καθώς και στα οικονομικά οφέλη που προκύπτουν από την εφαρμογή του. Επίσης παρουσιάζοντα τα προβλήματα ερμηνείας και εφαρμογής του κανονισμού. Ακολουθεί το έκτο κεφάλαιο, στο οποίο γίνεται αναφορά στην εφαρμογή του κανονισμού REACH στην Ελλάδα καθώς παρουσιάζεται η υπεύθυνη αρμόδια αρχή για την εφαρμογή του κανονισμού και ο ρόλος της, το πεδίο εφαρμογής του κανονισμού (επιχειρήσεις χημικών προϊόντων) καθώς και ο ρόλος του Συνδέσμου Ελληνικών Χημικών Βιομηχανιών. Τέλος στα συμπεράσματα γίνεται μια συγκεντρωτική παρουσίαση και σύγκριση των αρνητικών και θετικών χαρακτηριστικών του κανονισμού και αποτιμάται ο βαθμός της επίτευξης των αρχικών στόχων του μέσα στο χρονικό διάστημα από την ημερομηνία εφαρμογής του έως σήμερα. Επίσης παρουσιάζεται πως ο κανονισμός REACH αποτελεί καινοτόμο νομοθετικό εργαλείο στα χέρια της διοίκησης αν και αποδυναμωμένος σε σχέση με το αρχικό του κείμενο και την αρχική πεποίθηση για ολοκληρωμένη και υψηλού επιπέδου προστασία της ανθρώπινης υγείας και του περιβάλλοντος. / Aim of this work is the analysis of new legal regime of management and control of chemical substances in European level and the emergence of diverse implications that this poses. This new legal regime, despite its long-lasting consultation, is not finally exempted from weaknesses and problems of application. This is the new REACH Regulation (initials of the Registration, Evaluation and Authorisation of Chemicals) or regulation 1907/2006/EC. REACH is a uniform European legislation on the registration, evaluation, authorisation and restriction of chemicals, replacing 40 different existing legislative measures. The work is divided into the introduction, six chapters and finally conclusions. The introduction presents the existing EU legislation on chemicals, the problems of implementation as well as the need for a new legal framework which will replace the existing and will have as fundamental aim the protection of human health and environment. Reference is made to sustainable development and green chemistry, which are key pillars of the regulation. It also presents the basic principles of the regulation (precautionary principle, substitution principle, etc) as well as the objectives pursued by its application. In the first chapter becomes an analytic presentation of precaution principle, which constitutes basic and fundamental principle of regulation. Reference is made in relation to the prevention principle, in European law and food policy in the European Union as well as its confrontation from Greek law system. In the second chapter is presented in detail the construction of REACH regulation, by means of the most important chronological facts that sometimes reinforced and sometimes watered down regulation, satisfying each time and different interests or requirements, until the finalization of the final text. Special reference to the role of the World Trade Organization is made for the configuration of final text of regulation. Afterwards, in the third chapter, are presented in detail the field of application of regulation, the institutional bodies and their competences as well as the basic provisions of regulation, the registration, evaluation, authorisation and restriction of chemicals. Fourth chapter follows, where regulation CLP is presented (initials of the Classification, Labeling and Packaging) for the classification, labeling and packaging of substances and mixtures or regulation 1272/2008/EC. Regulation CLP supplements and modifies regulation REACH in the void that it presents with regard to the classification, labeling and packing of chemical substances and it harmonizes REACH with the World Harmonized System of classification and labeling for the chemical substances and mixtures of United Nations. In the fifth chapter becomes an analytic assessment of regulation REACH, while are presented and analyzed both positive aspects and weaknesses. A detailed reference becomes in the cost of implementing the regulation and to the economic benefits arising from its application. Also the problems in the interpretation and application of the regulation are presented. Following the sixth chapter, in which reference is made in the implementation of reach in Greece as the responsible authority for the application of the regulation and its role, the field of application of regulation (enterprises of chemical products) as well as the role of the Association of Greek Chemical Industries. Finally, in the conclusions is a summary and comparison of negative and positive characteristics of regulation and evaluation of the extent of the initial objectives within the period from the date of application until now. It also shows that REACH is an innovative legislative tool in the hands of the administration, although weak compared to the initial text, and the initial conviction for integrated and high level of protection of human health and environment.

Within the context of debates concerning the reception and interpretation of media texts by television audiences, this qualitative reception study explores how a sample of Bulawayo students negotiate meanings from Zimbabwe's first health communication soap opera, Studio 263. The study thus examines the reasons behind the popularity of this programme with this target audience. The findings of the study reveal that meaning making is a complex process that is dependent on a variety of factors which include, among others, the socio-cultural context of media consumption, gender, economic disposition and age. It particularly maintains that gender and lived realities influence the interpretation and negotiation of meanings in this particular study. / Adobe Acrobat Pro 11.0.0 Paper Capture Plug-in

Nickel based superalloys are currently being investigated for high temperature applications in advanced steam power plant operating at temperatures of 700˚C and above. Three nickel-based superalloys Inconel 617, Inconel 625 and Nimonic 263 alloys, which are of primary interest for boiler technology components such as furnace walls, superheater tubes, header and steam pipes, etc and for steam turbine technology components such as HP &IP cylinders, rotor forgings, casing and valve chest, blading, etc., have been evaluated for long and short term creep performance. Creep deformation processes occurring at high temperatures and stresses lead to the evolution of microstructures in the form of precipitation, precipitate coarsening and recovery effects. The deterioration in mechanical properties as a result of this microstructural change has been evaluated by hardness testing. This work discusses the microstructural evolution occurring in alloys in samples that have been creep exposed at a series of temperatures from 650°C to 775°C and for durations from 1000 to 45,000 hours using advanced FEGSEM, TEM, XRD and phase extraction techniques. The fractions and morphology of different phases, their locations during exposure to higher temperatures and probable creep fracture mechanism in these alloys are illustrated and discussed.

This thesis argues that the Feast of the Discovery of the Cross offered an occasion to refute religious opposition to the cross and crucifixion in the diverse socio-political contexts encountered by Syriac Christians between the fourth and the ninth centuries. At its inception, the Feast of the Cross promoted the cult of the True Cross, Old Testament typology, and the expansion of the Christian faith, and these features were sufficiently malleable to meet new religious challenges and political contexts. John of Dara's ninth-century homily On the Cross is a lengthy exposition on the veneration of the cross, and it showcases how the feast could be used for apologetic ends. The first chapter focuses on the relic of the True Cross and the theologies of the cross of Eusebius of Caesarea, Cyril of Jerusalem, and Ephrem the Syrian, which shaped later festal celebrations. The second chapter traces the development of the legend of Helena's Invention of the Cross and introduces the most popular Syriac invention legends, the Protonike and Judah Kyriakos legends. The third chapter analyses themes in pre-Arab Conquest Syriac homilies for the Feast of the Cross by Narsai, David Eskolaya, Jacob of Serugh, Severus of Antioch, and Pseudo-Chrysostom. The fourth chapter provides an overview of the dramatic changes of the seventh century during the reign of Heraclius and following the Arab Conquest. Chapter five compares inter-religious debate concerning the cross and crucifixion between Christians and Jews and between Christians and Muslims between the seventh and ninth centuries. Chapter six introduces John of Dara's homily for the Feast of the Cross, which uses the traditional themes, together with apologetic topics, to defend the veneration of the cross. Chapter seven explores the influence of John of Dara's homily on later Syrian Orthodox writers, Moshe bar Kepha and Dionysius bar Ṣalībī.

Indiana University-Purdue University Indianapolis (IUPUI) / HEVC has achieved significant coding efficiency improvement beyond existing video coding standard by employing many new coding tools. Deblocking Filter, Sample Adaptive Offset and Adaptive Loop Filter for in-loop filtering are currently introduced for the HEVC standardization. However these filters are implemented in spatial domain despite the fact of temporal correlation within video sequences. To reduce the artifacts and better align object boundaries in video , a new algorithm in in-loop filtering is proposed. The proposed algorithm is implemented in HM-11.0 software. This proposed algorithm allows an average bitrate reduction of about 0.7% and improves the PSNR of the decoded frame by 0.05%, 0.30% and 0.35% in luminance and chroma.