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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Ανάπτυξη συστημάτων κωδίκων για την ανίχνευση και διόρθωση σφαλμάτων σε δεδομένα μετάδοσης

Τυχόπουλος, Αυξέντιος 16 June 2010 (has links)
Το ερευνητικό αντικείμενο της παρούσας διατριβής υπάγεται στον «Έλεγχο Σφαλμάτων» (Error Control), έναν επιστημονικό χώρο με καθοριστικής σημασίας συνεισφορά στην εξέλιξη των ψηφιακών τηλεπικοινωνιών. Πιο συγκεκριμένα, η παρούσα διατριβή πραγματεύεται την εφαρμογή του «ελέγχου σφαλμάτων» στην οπτική μετάδοση. Κατά τη διάρκεια της τελευταίας δεκαπενταετίας (‘93-‘08), τρεις γενιές «άμεσης διόρθωσης σφαλμάτων» (FEC) έχουν διαδεχθεί η μία την άλλη, σε ανταπόκριση προς τις ολοένα απαιτητικότερες προδιαγραφές των οπτικών ζεύξεων (υψηλότεροι ρυθμοί μετάδοσης και πυκνότερα οπτικά πλέγματα). Κατά κανόνα, οι μέθοδοι FEC κωδικοποιούν τα δεδομένα εισόδου χωρίς να έχουν γνώση γι’ αυτά (π.χ. δομή, πρωτόκολλο) και χωρίς να επεμβαίνουν σ’ αυτά. Η προσέγγιση αυτή καλείται «κωδικοποίηση εκτός ζώνης» (Out-Band Coding – OBC) και συνεπάγεται αύξηση του ρυθμού μετάδοσης στο οπτικό κανάλι σε σχέση με το ρυθμό των δεδομένων εισόδου, ανάλογα με το ποσοστό πλεονασμού του κώδικα. Ωστόσο, ο τελικός ρυθμός μετάδοσης στο κανάλι μπορεί να διατηρηθεί αμετάβλητος, αν το πρωτόκολλο μετάδοσης προβλέπει την ύπαρξη πλεονάσματος και μέρος αυτού μπορεί να διατεθεί για κωδικοποίηση FEC. Η εναλλακτική αυτή προσέγγιση καλείται «κωδικοποίηση εντός ζώνης» (In-Band Coding – IBC). Η «σύγχρονη ψηφιακή ιεραρχία» (SDH) και το «σύγχρονο οπτικό δίκτυο» (SONET) είναι τα πρότυπα, που σήμερα κυριαρχούν στις οπτικές τηλεπικοινωνίες. Με αφθονία πλεονάσματος στα πλαίσια μετάδοσης, τα παραπάνω σύγχρονα δίκτυα προσφέρονται για την IBC. Στα πλαίσια της παρούσας διατριβής, τα SDH & SONET αναλύθηκαν από κοινού για την εύρεση της βέλτιστης μεθόδου IBC με βάση έναν αριθμό από κριτήρια. Καταρχήν εξετάστηκε διεξοδικά το πλεόνασμα μετάδοσης για να εντοπιστούν τα διαθέσιμα bytes και να αιτιολογηθεί η δέσμευσή τους για την IBC. Στη συνέχεια, αναζητήθηκε ο βέλτιστος κώδικας FEC για τα δεδομένα πλαίσια μετάδοσης και με το δεδομένο πλεόνασμα (για την αποθήκευση των bits ισοτιμίας του κώδικα). Η βελτιστοποίηση κάλυψε όλους τους γραμμικούς και συστηματικούς κώδικες ανά κατηγορίες – ο χωρισμός τους σε κατηγορίες έγινε με βάση τις εξής βασικές ιδιότητες: α) την αλφάβητο: «δυαδικοί» έναντι «μη-δυαδικών», και β) τη διορθωτική ικανότητα: κώδικες κατάλληλοι για «τυχαία» (μεμονωμένα) σφάλματα έναντι κατάλληλων για «ομοβροντίες» (ριπές) σφαλμάτων. iii Από την παραπάνω διαδικασία βελτιστοποίησης προέκυψε μία μέθοδος IBC, που βασίζεται στο συρρικνωμένο Reed-Solomon κώδικα RS(240,236,9). Πρόκειται για μία εντελώς νέα μέθοδο και δικαιολογεί τη διάκρισή της ως βέλτιστη, έχοντας σαφή πλεονεκτήματα έναντι των μεθόδων, που είχαν προταθεί στο παρελθόν. Στα πλαίσια της παρούσας διατριβής, η παραπάνω βέλτιστη μέθοδος προτείνεται με το όνομα «FOCUS» για την κωδικοποίηση IBC στα δίκτυα SDH/SONET. Με στόχο την ακριβή πειραματική αξιολόγηση της προτεινόμενης μεθόδου FOCUS, υλοποιήθηκε κατόπιν ένας αριθμός από πρωτότυπα συστήματα, χρησιμοποιώντας τις διαθέσιμες μικροκυματικές κάρτες «10g-Tester». Αναλυτικότερα, η μοντελοποίηση έγινε στη γλώσσα περιγραφής υλικού VHDL και η υλοποίηση με προγραμματιζόμενη λογική (Xilinx® XC2V3000-4 FPGA). Τέλος, η πειραματική αξιολόγηση της προτεινόμενης μεθόδου FOCUS πραγματοποιήθηκε σε δύο διαδοχικές φάσεις: Στην πρώτη φάση, το σύστημα FOCUS αξιολογήθηκε ως μία «ανεξάρτητη» μέθοδος κωδικοποίησης FEC (stand-alone IBC evaluation). Η αξιολόγηση έγινε με ρυθμό μετάδοσης STM-64 σε κατάλληλα διαμορφωμένη, πειραματική οπτική ζεύξη «από-σημείο σε-σημείο» (point-to-point optical link), συνολικού μήκους ~88 χμ. Στην παραπάνω ζεύξη μετρήθηκαν οι επιδόσεις του FOCUS κατά την αντιστάθμιση των κυριότερων ατελειών της οπτικής μετάδοσης: α) της χρωματικής διασποράς (CD), β) της «παρασιτικής» ενίσχυσης του θορύβου από οπτικούς ενισχυτές (ASE) και γ) της μη-γραμμικής συμπεριφοράς (WDM -NL). Στη δεύτερη φάση, το σύστημα FOCUS αξιολογήθηκε ως μία «αναβάθμιση» για οπτικές ζεύξεις, οι οποίες διαθέτουν ήδη κωδικοποίηση OBC (evaluation of IBC and OBC in concatenation). Πιο συγκεκριμένα, το σύστημα FOCUS συνδέθηκε σε σειρά (ως εξωτερικός κώδικας) με το κατά ITU-T G.975 (2000) πρότυπο σύστημα κωδικοποίησης (OBC). Σε αυτή τη συνδεσμολογία, το σύστημα FOCUS αποτελεί τη δικλείδα ασφαλείας, που επεμβαίνει όταν ο εσωτερικός αποκωδικοποιητής (G.975) υπερχειλίζεται από τα σφάλματα του καναλιού. Η αξιολόγηση της υβριδικής αυτής μεθόδου κωδικοποίησης έγινε με ρυθμό μετάδοσης 10.66 Gb/s (SDH STM-64 x 15/14) σε μία καθαρά οπτική διάταξη μετατροπής μήκους κύματος, που αποτελείται από δύο οπτικούς ενισχυτές πυριτίου (SOA-based MZI). Ειδικότερα, μετρήθηκαν: α) η μείωση της ευαισθησίας της οπτικής διάταξης στις (τυχαίες) μεταβολές φάσης των δύο σημάτων εισόδου και β) η καθαρή συνεισφορά του συστήματος FOCUS, όταν αυτό επεμβαίνει ως δικλείδα ασφαλείας. Το FOCUS συγκεντρώνει σημαντική καινοτομία, τόσο στην επινόηση όσο και στην υλοποίηση. Όλα τα συμπεράσματα της αξιολόγησης έχουν δημοσιευτεί σε έγκυρα διεθνή περιοδικά και συνέδρια. / This Ph.D. thesis falls into “Error Control”, a scientific field with key contribution to the evolution of digital telecommunications. In specific, this thesis treats optical transmission in terms of “Error Control”. Noteworthy is the fact that during the last fifteen years (‘93-‘08), three generations of “Forward Error Correction” (FEC) methods for optical transmission have succeeded one another, in response to the increasingly demanding optical link specifications (higher transmission rates, denser wavelength mesh). In general, FEC-methods assume no prior knowledge of the input data (e.g. structure, protocol); in addition, input data are not modified at all (i.e. under normal channel conditions, output-data will be identical to the input data). This approach is called “Out-Band Coding” (OBC) and incurs an increase of the optical channel data-rate relatively to the input data-rate, inversely proportional to the coding-rate. Notwithstanding, the rate of the optical-channel can be kept unchanged, on condition that the transmission protocol provides “overhead” and part of this “overhead” can be allocated for parity-information. This alternative approach is called “In-Band Coding” (IBC). The “Synchronous Digital Hierarchy” (SDH) and the “Synchronous Optical Network” (SONET) are currently the dominant standards in optical communications. The abundance of overhead in transmission-frames renders these synchronous networks suitable for IBC. In this thesis, SDH and SONET were analyzed together to determine the optimum IBC method with respect to a number of criteria. Firstly, SDH/SONET transmission-overhead was scrutinized in order to identify available bytes and justify their commitment to implement IBC. Next, the optimum FEC-code was sought, given the size of the transmission-frames and the availability of overhead (to allocate the parity bits). Optimization spanned all linear and systematic codes. The codes were divided in groups according to the following fundamental properties: a) the underlying alphabet: “binary” versus “non-binary” codes, and b) the corrective power: codes, appropriate for “random” (isolated) errors versus codes, appropriate for “burst-form” errors. Optimization resulted in an IBC-method, which relies on the shortened Reed-Solomon code RS(240,236,9). This IBC-method is completely novel and its optimality can be verified by the clear advantages, it presents over methods that were proposed in the past. In this thesis, the above IBC-method is given the name “FOCUS” and proposed for IBC in SDH/SONET networks. In order to accurately measure the performance of the proposed method “FOCUS”, a number of prototypes were implemented by making use of microwave cards, called “10gv Tester”. More specifically, “FOCUS” was modelled in the “VHDL” hardware description language and its prototypes were implemented by means of a Xilinx® “XC2V3000-4” FPGA. The experimental evaluation of the proposed method was conducted in two successive phases: During the first phase, “FOCUS” was evaluated as an independent (stand-alone) FEC method. This evaluation took place at an STM-64 transmission-rate in a suitable experimental “point-to-point” optical link, whose length was ~88 km. In the above link, the performance of “FOCUS” was measured, in compensating the principal impairments of optical transmission: a) the chromatic dispersion (CD), b) the parasitic amplification of noise by optical amplifiers (ASE), and c) the non-linear behavior (WDM-NL). During the second phase, “FOCUS” was evaluated as an “upgrade” for optical links, which have already been equipped with OBC (evaluation of IBC and OBC in concatenation). Specifically, “FOCUS” was concatenated with the OBC-method, which has been proposed in rec. G.975 (ITU-T, 2000) with “FOCUS” as the outer- and “G.975” as the inner-code. In this arrangement, “FOCUS” plays the role of the “safety-valve”, which prevents the inner decoder (G.975) from deteriorating the error-rate of the optical link, when it is overwhelmed by severe channel-conditions. The evaluation of this hybrid coding-method took place at a transmissionrate of 10.66 Gb/s (SDH STM-64 x 15/14) in a purely optical wavelength conversion device, which consists of two silicon optical amplifiers (SOA-based MZI). In the above wavelengthconversion device, the following measurements were obtained: a) the reduction of sensitivity of the optical wavelength converter to the (random) phase-changes of the two input signals, and b) the net contribution of “FOCUS”, when acting as a “safety valve”. “FOCUS” has many innovative aspects, both in its conception and the implementation of its prototypes. All conclusions of the above two-phased experimental evaluation have been published in international journals and conferences.
232

Jiří Kotalík a Spojené státy americké / Jiří Kotalík and the United States of America

Červená, Veronika January 2022 (has links)
The main focus of this diploma thesis is Jiří Kotalík, his relationship with the United States of America and projects in which he participated as the director of the National Gallery in Prague. To understand projects, it was necessary to clarify the broader circumstances, especially the relationship of the Czechoslovak Socialist Republic to the United States of America and the cultural policy of both states. Therefore, the time frame was extended, both in the historical introduction and the first exhibition of American art in Czechoslovakia in 1947. It was also necessary to put into context the purpose for which large traveling exhibitions and other US cultural projects were organized and what reception they caused in the Czechoslovak Socialist Republic. The six largest exhibitions of American art, which took place in the Czechoslovak Socialist Republic in the years 1967-1990, were selected as a sample. In the end, other forms of cooperation of the National Gallery, respectively Jiří Kotalík with American institutions were indicated but also other forms of promotion of Czechoslovak art in the United States of America were indicated. Key words: Jiří Kotalík, National Gallery in Prague, Czechoslovak Socialist Republic, USA, Thomas Messer, Solomon R. Guggenheim Museum, propaganda, cultural policy,...
233

300 MBPS CCSDS Processing Using FPGA's

Genrich, Thad J. 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper describes a 300 Mega Bit Per Second (MBPS) Front End Processor (FEP) prototype completed in early 1993. The FEP implements a patent pending parallel frame synchronizer (frame sync) design in 12 Actel 1240 Field Programmable Gate Arrays (FPGA's). The FEP also provides (255,223) Reed-Solomon (RS) decoding and a High Performance Parallel Interface (HIPPI) output interface. The recent introduction of large RAM based FPGA's allows greater high speed data processing integration and flexibility to be achieved. A proposed FEP implementation based on Altera 10K50 FPGA's is described. This design can be implemented on a single slot 6U VME module, and includes a PCI Mezzanine Card (PMC) for a commercial Fibre Channel or Asynchronous Transfer Mode (ATM) output interface module. Concepts for implementation of (255,223) RS and Landsat 7 Bose-Chaudhuri-Hocquenghem (BCH) decoding in FPGA's are also presented. The paper concludes with a summary of the advantages of high speed data processing in FPGA's over Application Specific Integrated Circuit (ASIC) based approaches. Other potential data processing applications are also discussed.
234

The artistic discovery of Assyria by Britain and France 1850 to 1950

Esposito, Donato January 2011 (has links)
This thesis provides an overview of the engagement with the material culture of Assyria, unearthed in the Middle East from 1845 onwards by British and French archaeologists. It sets the artistic discovery of Assyria within the visual culture of the period through reference not only to painting but also to illustrated newspapers, books, journals, performances and popular entertainments. The thesis presents a more vigorous, interlinked, and widespread engagement than previous studies have indicated, primarily by providing a comprehensive corpus of artistic responses. The artistic connections between Britain and France were close. Works influenced by Assyria were published, exhibited and reviewed in the contemporary press, on both sides of the English Channel. Some artists, such as Gustave Doré, successfully maintained careers in both London and Paris. It is therefore often meaningless to speak of a wholly ‘French’ or ‘British’ reception, since these responses were coloured by artistic crosscurrents that operated in both directions, a crucial theme to be explored in this dissertation. In Britain, print culture also transported to the regions, away from large metropolitan centres, knowledge of Assyria and Assyrian-inspired art through its appeal to the market for biblical images. Assyria benefited from the explosion in graphical communication. This thesis examines the artistic response to Assyria within a chronological framework. It begins with an overview of the initial period in the 1850s that traces the first British discoveries. Chapter Two explores the different artistic turn Assyria took in the 1860s. Chapter Three deals with the French reception in the second half of the nineteenth century. Chapter Four concludes the British reception up to 1900, and Chapter Five deals with the twentieth century. The thesis contends that far from being a niche subject engaged with a particular group of artists, Assyrian art was a major rediscovery that affected all fields of visual culture in the nineteenth century.
235

Kniha Píseň písní jako odpověď na Kazatelovu marnost / The Book Song of Songs as an Answer to Qohelet's Vanity

FILIPOVÁ, Anna January 2019 (has links)
This thesis is concerned with, in the words of Song of Songs, finding an appropriate answer to Qohelet's vanity - vanity of a human life and things that inherently come with it, as Qohelet himself proclaims in his book. The first chapter introduces the Book of Qohelet and aims to capture the main themes of vanity and transience, while also providing the ways out from this situation, as presented by Qohelet. The second chapter introduces the reader to the Song of Songs book while also describing its content which concerns the interpretation of love between a man and a woman. The third chapter brings forward efforts of the author and the main themes and conclusions of the book are analysed. This allows - in the conclusion of this thesis - to answer the question of whether the love in the Songs of Songs is a possible answer to Qoheleth's vanity - the transience of a human life, as brought out by Qohelet in his work.
236

Décodage des codes algébriques et cryptographie

Augot, Daniel 07 June 2007 (has links) (PDF)
Je traite du décodage de deux grandes familles de codes algébriques :<br />les codes cycliques binaires et les codes de Reed-Solomon sur un<br />alphabet $q$-aire (ainsi que les codes géométriques). En ce qui<br />concerne les codes cycliques, ceux-ci n'ont pas d'algorithme générique<br />de décodage, mis à part les codes BCH ou assimilés (bornes de<br />Hartman-Tzeng, de Roos). Au premier rang des codes intéressants pour<br />lesquels on ne connaît pas d'algorithme de décodage {\em générique}<br />figurent les {\em codes à résidus quadratiques}, qui ont de bons<br />paramètres. J'étudie une mise en équation du problème du décodage par<br />syndrôme de ces codes, que l'on peut résoudre avec des outils de base<br />de Gröbner. On obtient ainsi des algorithmes de décodage de complexité<br />raisonnable pour ces codes. Ces travaux ont fait l'objet d'une partie<br />de la thèse de Magali Bardet.<br /><br /><br />En ce qui concerne les codes de Reed-Solomon, ceux-ci peuvent être vus<br />comme des {\em codes d'évaluation}, et le problème de décodage associé<br />revient à approcher une fonction par des polynômes de base degré. De<br />grands progrès ont été réalisés par Guruswami et Sudan, qui ont trouvé<br />un algorithme qui décode bien au delà des rayons classiques de<br />décodage, en relaxant l'hypothèse que la solution doit être unique. Je<br />propose d'améliorer certaines étapes de cet algorithme, en le rendant<br />plus rapide et déterministe (notamment en évitant une factorisation de<br />polynôme sur un corps fini), dans le cas des codes Reed-Solomon, et<br />dans le cas des codes géométriques. Ces travaux ont été effectués en<br />encadrant Lancelot Pecquet.<br /><br />Du point de vue théorique, j'ai étudié des généralisations<br />multivariées, qui correspondent à certains codes: les codes produits<br />de Reed-Solomon, et les codes de Reed-Muller. On obtient ainsi un bon<br />rayon de décodage, dans le cas des codes de petit taux. Dans le cas de<br />codes de Reed-Muller sur l'alphabet binaire, Cédric Tavernier, dans sa<br />thèse sous ma direction, a produit et implanté un algorithme efficace,<br />plus que ceux basés sur l'algorithme de Guruswami-Sudan.<br /><br /><br /><br />J'ai étudié les aspects négatifs du problème de décodage par syndrôme<br />des codes linéaires, et du décodage des codes de Reed-Solomon, quand<br />le nombre d'erreurs est élevé, en but d'application en cryptographie.<br />Dans le premier cas, j'ai construit une fonction de hachage<br />cryptographique à réduction de sécurité, c'est-à-dire que trouver une<br />faiblesse dans le fonction de hachage revient à résoudre un problème<br />réputé difficile de codage. J'ai aussi construit une nouvelle<br />primitive de chiffrement à clé publique, reposant sur la difficulté de<br />décoder les codes de Reed-Solomon.<br /><br />Dans un domaine plus appliqué, j'ai proposé avec Raghav Bhaskar un<br />nouvel algorithme d'échange de clé multi-utilisateurs, fondé sur le<br />problème du logarithme discret. Raghav Bhaskar a fourni une preuve de<br />sécurité de ce protocole, pendant sa thèse sous ma direction. Nous<br />avons aussi étudié comment adapter ce protocole aux pertes de<br />messages, car notre protocole est un des seuls qui est robuste à ces<br />pertes.
237

Creation and God as One, Creator, and Trinity in early theology through Augustine and its theological fruitfulness in the 21st century

Ellingwood, Jane January 2015 (has links)
My primary argument in this thesis is that creation theologies significantly influenced early developments in the doctrine of the Trinity, especially in Augustine of Hippo’s theology. Thus this is a work of historical theology, but I conclude with proposals for how Augustine’s theologies of creation and the Trinity can be read fruitfully with modern theology. I critically analyse developments in trinitarian theologies in light of ideas that were held about creation. These include the doctrine of creation ‘out of nothing’ and ideas about other creative acts (e.g., forming or fashioning things). Irenaeus and other early theologians posited roles for God (the Father), the Word / Son, the Spirit, or Wisdom in creative acts without working out formal views on economic trinitarian acts. During the fourth century trinitarian controversies, creation ‘out of nothing’ and ideas about ‘modes of origin’ influenced thinking on consubstantiality and relations within the Trinity. Basil of Caesarea and others also presented ideas about trinitarian acts of creation and the Trinity in hexaemeral works. I will argue that in Augustine’s views of trinitarian acts of creation, he attributes roles to God (the Father), the Word / Son, and the Spirit. In his mature theology, he attributes the giving of formless existence, differentiated existence, and perfected existence to the three Persons respectively, while depicting shared roles. He also attributes to the Spirit the giving of the capability of ‘dynamic abiding’ to creatures, which gives them agency in continuing their existence. Augustine’s theologies of creation and the Trinity were significantly influenced by his exegesis of Gen. 1, John 1. 1-3, Wisdom, and other scriptures, and his ideas resonate with the hexaemeral works of Basil and Philo of Alexandria. I argue that scholars should examine these sources and Augustine’s own hexaemeral commentaries to gain a deeper understanding of his trinitarian theology.
238

Systém pro rozpoznávání čárových kódů / Barcode recognition system

Pribula, Wojciech January 2015 (has links)
This thesis describes barcodes which are used in postal services. Specifically, it is concerned with Intelligent Mail Barcode, the GS1-128 code, the C128 code of Ceska posta (Czech Postal Services) and the QR code. The thesis attempts to analyze methods of encoding information into barcodes and error detection algorithms used for error correction during the decoding processes. Most importantly, there is described Reed-Solomon error correction in the QR code. There are presented and evaluated different methods of code detecting which are suggested by authors of various academic articles. The thesis also describes the method of creating test sets of images and proposed appearances of the scanning scene. Additionally, there are described algorithms for detection and decoding barcodes GS1-128, C128 and IMB in the image which was created during the work on this thesis. Finally, there is the evaluation of the percentage success of algorithms.
239

Možnosti kódového zabezpečení stanic s kmitočtovým skákáním / Possibilities of Error Controls in Frequency hopping Stations

Pust, Radim January 2012 (has links)
The doctoral thesis deals with design of coding for frequency hopping stations in band with intensive jamming. In digital modulations erroneous determination of the modulation state occurs due to jam at the receiver side. The result is erroneously transferred symbols of the message. Errors created during the transmission can be eliminated by using error control systems. It is also possible to prevent these errors by using algorithms (techniques) of frequency hopping which select the appropriate channel. Appropriate communication channel is a channel with a lower probability of erroneous symbol in the message. The main contribution of this thesis is to design a new frequency hopping technique with collision avoidance (FH/CA). The station with FH/CA technique measures signal levels in the considered several channels before every jump. Based on the measurements the most appropriate channel with the lowest value of measured signal level is selected. Therefore, it is more probable that a jump to an unoccupied channel with a transmission will occur. Using a mathematical model, the performance of the newly proposed FH/CA technique is compared with the currently used techniques FH and AFH. Comparison criteria are the probability of a collision between an FH/CA communication system and a static (device transmitting continuously at a fixed frequency) or dynamic jammer (i.e. other FH or AFH systems). By comparing the values of the probability of jammed transmission, indisputable theoretical advantages of the new FH/CA technique were found, compared to the currently used FH and AFH techniques. The FH/CA technique always has better or equal results compared with the FH technique in the case of interference by static and dynamic jammers. The FH/CA technique in a band with static and dynamic jammers usually has better results than the AFH technique. A significant contribution of the FH/CA technique can be seen in the case of dynamic jammers. On the other hand, in the case of static jammers the FH/CA technique is in certain situations worse than the AFH technique. The accuracy of the mathematical models were successfully verified on a simulation model that was created as a part of this thesis in the MATLAB environment. Based on the obtained data from the model there was designed coding for frequency hopping stations with the new technique of frequency hopping FH/CA which is designed for small-volume data transfer in a band with intensive jamming.
240

Blackness as the way to and state of salvation: a search for true salvation in South Africa today

Senokoane, B. B. 09 1900 (has links)
The dissertation is titled: “Blackness as the way to and state of salvation: A search for true salvation in South Africa today”. The research was prompted by the question of salvation and what it means for blacks. The provocation arose out of the problem and/or interpretation of classical theology on the subject of soteriology. The biblical text of the Song of Songs 1:5: “I am black and beautiful, O daughters of Jerusalem, like the tents Qedar, like the curtains of Solomon”, is used as key to the argument. Origen (an early Christian theologian, who was born and spent the first half of his career in Alexandria) interpretation of the preceding biblical text is identified as problematic for blackness and African salvation. The problem identified with his interpretation of the said text and its theology and/or soteriology is that, first; he identifies and affirms the “ugliness’ of the black external and physical colour and/or conditions. Secondly, his theology and/or soteriology is identified as dualistic, separating the physical and the soul, which the researcher challenges and is against it as does not reflect the understanding of soteriology and/or theology by Africans. The researcher attacks and argues against the ugliness of blackness and dualism as a white and Eurocentric logic and problem. The researcher in his argument exposes whiteness and eurocentrism as problematic. The problem associated with whiteness is its claim that it is beautiful and positions itself as the way of and to salvation. Moreover, whiteness is problematised as a racial identity, position of power, structural evil and sin, exploitative, oppressive, and as related to capitalism. In response, the researcher, a black theologian argues against the theology of Origen and labelling it as European and white. The researcher exposes blackness as beautiful, powerful, and as a way of life. For the researcher, salvation must be understood as holistic and as here and now, situated in the black conditions. The researcher argues against dualism and individualism in favour of a holistic and a communal African approach that is not exclusive and self-centered. This approach is inclusive of the belief in God, the self, others human beings and the natural environment. He is propagating a black theology that is in favour of blackness as life, beautiful, powerful, liberating, and socialistic. / D. Th. (Systematic Theology)

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