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On the theoretical aspects of multi-carrier spread spectrum systems.January 1996 (has links)
by Tsan-Fai Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 64-68). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Review on spread spectrum communications --- p.1 / Chapter 1.2 --- The spread spectrum techniques --- p.2 / Chapter 1.2.1 --- Direct Sequence (DS) Systems --- p.2 / Chapter 1.2.2 --- Frequency Hopping (FH) Systems --- p.2 / Chapter 1.2.3 --- Time Hopping (TH) Systems --- p.4 / Chapter 1.2.4 --- Hybrid Systems --- p.4 / Chapter 1.3 --- Existing Applications of the spread spectrum systems --- p.5 / Chapter 1.4 --- Organization of the thesis --- p.6 / Chapter 2 --- The Concept of Duality --- p.7 / Chapter 2.1 --- Multi-Carrier Systems - An Overview --- p.7 / Chapter 2.2 --- Orthogonal Frequency Division Multiplexing --- p.8 / Chapter 2.2.1 --- Bandwidth Efficiency --- p.9 / Chapter 2.2.2 --- Spectral Efficiency --- p.10 / Chapter 2.2.3 --- Effects of fading --- p.11 / Chapter 2.3 --- Applications of OFDM in multiple access --- p.13 / Chapter 2.3.1 --- ST-CDMA --- p.13 / Chapter 2.3.2 --- MC-DS-CDMA --- p.14 / Chapter 2.3.3 --- OFDM-CDMA --- p.15 / Chapter 2.4 --- Duality - Time-Frequency Interrelation --- p.16 / Chapter 3 --- Performance of Multi-Carrier CDMA System --- p.17 / Chapter 3.1 --- System Model --- p.17 / Chapter 3.2 --- Performance Analysis --- p.20 / Chapter 3.2.1 --- Gaussian Channel --- p.20 / Chapter 3.2.2 --- Fading Channel --- p.24 / Chapter 3.3 --- Performance with Pulse Shape --- p.33 / Chapter 3.4 --- Appendix --- p.34 / Chapter 4 --- Signal Design Criteria for MC-CDMA System --- p.36 / Chapter 4.1 --- Existence of Signal Distortion --- p.37 / Chapter 4.2 --- Measures of the Signal Envelope Fluctuation --- p.38 / Chapter 4.3 --- Complementary Sequences --- p.41 / Chapter 4.4 --- Crest Factors --- p.42 / Chapter 4.4.1 --- Time-limited Pulse --- p.43 / Chapter 4.4.2 --- Ideally Band-Limited Pulses --- p.43 / Chapter 4.4.3 --- Shaped Pulses --- p.45 / Chapter 4.5 --- Spectrally Efficient Complementary (SEC) Sequences --- p.48 / Chapter 4.6 --- Construction of Spectrally Efficient Complementary(SEC) Sequences --- p.50 / Chapter 4.7 --- Generalized Multiphase Spectrally Efficient Complementary Sequences --- p.55 / Chapter 5 --- Summary and Future Extensions --- p.58 / Chapter 5.1 --- Summary of the Results --- p.58 / Chapter 5.2 --- Topics for Future Research --- p.59 / Appendix / Chapter A --- Exhaustive search of MPSEC sequences --- p.61 / Chapter B --- Papers derived from this thesis --- p.63 / Bibliography --- p.64
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New adaptive transmission schemes for MC-CDMA systems.January 1999 (has links)
by Yin-Man Lee. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 82-[87]). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview of MC-CDMA --- p.1 / Chapter 1.2 --- System Model --- p.3 / Chapter 1.3 --- Receiver Optimization --- p.7 / Chapter 1.4 --- Transmitter Optimization --- p.9 / Chapter 1.5 --- Nonlinearly Constrained Optimization --- p.10 / Chapter 1.6 --- Outline of Thesis --- p.11 / Chapter 2 --- Centralized Transmitter Optimization for MC-CDMA Systems --- p.13 / Chapter 2.1 --- Introduction --- p.13 / Chapter 2.2 --- Problem Development --- p.15 / Chapter 2.3 --- Lagrangian Optimization Approaches --- p.16 / Chapter 2.3.1 --- Penalty Function Method --- p.17 / Chapter 2.3.2 --- Barrier Function Method --- p.19 / Chapter 2.3.3 --- Powell's Method and Augmented Lagrangian Method --- p.21 / Chapter 2.4 --- Optimal FDMA System --- p.23 / Chapter 2.5 --- Modified Centralized Optimization Schemes --- p.25 / Chapter 2.6 --- Performance --- p.27 / Chapter 2.6.1 --- Typical Behavior --- p.27 / Chapter 2.6.2 --- Average Performance --- p.32 / Chapter 2.7 --- Summary --- p.38 / Chapter 3 --- Decentralized Transmitter Optimization for MC-CDMA Sys- tems --- p.39 / Chapter 3.1 --- Introduction --- p.39 / Chapter 3.2 --- System Model --- p.41 / Chapter 3.3 --- Optimization --- p.42 / Chapter 3.3.1 --- Receiver Optimization --- p.43 / Chapter 3.3.2 --- Single-user Transmitter Optimization --- p.44 / Chapter 3.3.3 --- Decentralized Transmission Scheme --- p.45 / Chapter 3.3.4 --- Multirate Transmission with Decentralized Transmission Scheme --- p.47 / Chapter 3.4 --- Performance --- p.48 / Chapter 3.5 --- Summary --- p.57 / Chapter 4 --- Performance Evaluation of Various Adaptive Transmission Schemes --- p.59 / Chapter 4.1 --- Introduction --- p.59 / Chapter 4.2 --- Comparison of Different Adaptive Transmission Schemes --- p.61 / Chapter 4.3 --- Adaptive Transmission Schemes with K > M --- p.64 / Chapter 4.4 --- Modified Adaptive Transmission Scheme with Graceful Degrada- tion in the SNR --- p.68 / Chapter 4.5 --- Summary --- p.71 / Chapter 5 --- Conclusions and Future Work --- p.73 / Chapter 5.1 --- Conclusions --- p.73 / Chapter 5.2 --- Future Work --- p.75 / A The Hungarian Method for Optimal Frequency Assignment --- p.76 / Bibliography --- p.82
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Semidefinite programming, binary codes and a graph coloring problemLi, Chao 29 May 2015 (has links)
"Experts in information theory have long been interested in the maximal size, A(n, d), of a binary error-correcting code of length n and minimum distance d, The problem of determining A(n, d) involves both the construction of good codes and the search for good upper bounds. For quite some time now, Delsarte's linear programming approach has been the dominant approach to obtaining the strongest general purpose upper bounds on the efficiency of error-correcting codes. From 1973 forward, the linear programming bound found many applications, but there were few significant theoretical advances until Schrijver proposed a new code upper bound via semidefinite programming in 2003. Using the Terwilliger algebra, a recently introduced extension of the Bose-Mesner algebra, Schrijver formulated a new SDP strengthening of the LP approach. In this project we look at the dual solutions of the semidefinite programming bound for binary error-correcting codes. We explore the combinatorial meaning of these variables for small n and d, such as n = 4 and d = 2. To obtain information like this, we wrote a computer program with both Matlab and CVX modules to get solution of our primal SDP formulation. Our program efficiently generates the primal solutions with corresponding constraints for any n and d. We also wrote a program in C++ to parse the output of the primal SDP problem, and another Matlab script to generate the dual SDP problem, which could be used in assigning combinatorial meaning to the values given in the dual optimal solution. Our code not only computes both the primal and dual optimal variable values, but allows the researcher to display them in meaningful ways and to explore their relationship and dependence on arameters. These values are expected to be useful for later study of the combinatorial meaning of such solutions."
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Conversational code-switching and word borrowing among Libyans speaking the Benghazi Arabic dialect : a sociolinguistic studyElbouri, Sousen Wahbi January 2019 (has links)
No description available.
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A genetic analysis of the secretion of β-lactamaseKoshland, Douglas Elliott January 1982 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Biology, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE / Vita. / Bibliography: leaves 211-223. / by Douglas Elliott Koshland. / Ph.D.
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Binary sequence adaptation for CDMA systems. / CUHK electronic theses & dissertations collection / Digital dissertation consortiumJanuary 2004 (has links)
Kwan Ho-yuet. / "April 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 98-[103]). / 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. / Abstracts in English and Chinese.
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Assessing and improving code transformations to support software evolution / Évaluation et amélioration des transformations de code pour soutenir l'évolution logicielleDe Souza Santos, Gustavo Jansen 28 February 2017 (has links)
Dans le domaine du développement logiciel, le changement est la seule constante. Les logiciels évoluent parfois de façon substantielle et, pendant ce processus, des séquences de transformation de code (par exemple, créer une classe, puis surcharger une méthode) sont systématiquement appliquées dans le système (e.g. à certaines classes dans une même hiérarchie). De par la nature répétitive de ces transformations, il est nécessaire d’automatiser leur support afin d’assurer que ces séquences de transformations sont appliquées de façon consistante sur la globalité du système.Dans cette thèse, nous proposons d’améliorer les transformations de code pour mieux aider les développeurs dans l’application de transformation de code systématiques et complexes. Nous couvrons deux aspects:• Le support automatisé pour composer et appliquer des séquences de transformations de code. Nous réalisons une recherche de l’existence de telles séquences dans de vrais logiciels. Nous proposons un outil pour appliquer automatiquement ces séquences dans les systèmes que nous avons analysés. • La détection de violations de bons principes dans la conception lors d’efforts de transformation. Nous proposons un outil qui recommande des transformations additionnelles pour résoudre les violations de conception qui ont pu être détectées après avoir effectué les transformations de refactoring.Nous évaluons les approches proposées quantitativement et qualitativement sur des cas d’étude issus du monde réel, parfois avec l’aide des experts du système analysé. Les résultats obtenus montrent la pertinence de nos approches. / In software development, change is the only constant. Software systems sometimes evolve in a substantial way and, during this process, sequences of code transformations (e.g., create a class, then override a method) are systematically performed in the system (e.g., to some classes in the same hierarchy). Due to the repetitive nature of these transformations, some automated support is needed to ensure that these sequences of transformations are consistently applied to the entire system.In this thesis we propose to improve source code transformations to better sup- port developers performing more complex and systematic code transformations. We cover two aspects: • The automated support to compose and apply sequences of code transformations. We undergo an investigation on the existence of these sequences in real-world software systems. We propose a tool to automatically apply these sequences in the systems we analyzed. • The detection of design violations during a transformation effort. We undergo an investigation on cases of systematic application of refactoring transformations. We proposed a tool that recommends additional transformations to fix design violations that are detected after performing refactoring transformations.We evaluated the proposed approaches quantitatively and qualitatively in real-world case studies and, in some cases, with the help of experts on the systems under analysis. The results we obtained demonstrate the usefulness of our approaches.
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Diglossia and code switching at MokopaneMatji, Raisibe Patricia January 2010 (has links)
Thesis (M.A (Translation studies and linguistics )) --University of Limpopo (Turfloop Campus), 2010. / This research is intended as a tool to survey the state of Sindebele, the speech variety that is predominantly spoken at Mokopane in the Limpopo Province of South Africa. The study will inform the reader, making use of a sociolinguistic approach, about the language situation at Mokopane. The study further provides a factual account as to what is happening at Mokopane concerning the two commonly spoken speech forms, that is, Sepedi and Sindebele. Furthermore, it presents ideas and insights in order to stimulate academic debates on the differences between isiNdebele and Sindebele and how the authorities are approaching the whole idea of Sindebele as a minority language.
The researcher used the qualitative method to have more insight into the language situation of the area. The tool the researcher will use in this research will be the structured interview that will enable her to obtain the required sample of the respondents.
The main aim of the researcher to conduct this research is to analyse the linguistic situation to understand the socio-political situation of the area.
The researcher has found that the issue of Sindebele is more of a political nature than social. The Sindebele speakers’ concern about the revival of their speech form seems to have gone in one ear and out the other, as a result, Sindebele may totally not be given recognition as a subject in schools.
Finally, the researcher gives general recommendations for improving the status of Sindebele.
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Grammatical constraints on child bilingual code mixingSauvé, Deanne. January 2000 (has links)
No description available.
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Preparation, optimisation and characterisation of sequence selective compoundsTaleb, Robin I., University of Western Sydney, College of Health and Science, School of Biomedical and Health Sciences January 2008 (has links)
DNA is the pharmacological target for most platinum drugs; however, the majority of these drugs show little or no specificity for particular base pairs. Considerable progress has been made in the design of sequence selective compounds, such that an antiparallel association of a polyamide can have high affinity for selected DNA base pairs. Hairpin polyamides have distinct advantages as they achieve affinities and specificities that are comparable to that of DNA-binding proteins. Platinum(II) hairpin polyamides are expected to display antitumour activity and target specific sequences of DNA. Five DNA-sequence-selective hairpin polyamide platinum(II) complexes, containing pyrrole (Py) and imidazole (Im) heterocyclic rings, have been synthesised using a combination of solid and solution phase chemistry. One mononuclear sequence selective complex, β-Ala-PyPyPy-L4-ImImIm-L4-Pt (HLSP-6) [β-Ala is β-alanine, L4 is 4-(Fmoc-amino)butyric acid and Pt is transplatin], and two dinuclear sequence selective complexes, β-Ala-PyPyPy-L4-ImImIm-L6'-Pt-(Pt) (DNHLSP-6) [L6' is 2,6-Fmoc-Lysine-(Fmoc)-OH] and β-Ala-PyPyImImIm-L4'-PyPyPyPyPy-L6'-Pt-(Pt) (DNHLSP-10) (L4' is 2-Boc-4-Fmoc-L-diaminobutyric acid), were synthesised entirely using solid phase chemistry. Two mononuclear sequence selective complexes, Pt-L6-β-Ala-Py-L4-Im (HSP-2) and Pt-L6-β-Ala-PyPyPy-L4-ImImIm (HSP-6), were synthesised using a combination of solid and solution phase chemistry. The synthesis of a trinuclear sequence selective polyamide was also attempted using a combination of solid and solution phase chemistry. The polyamides were synthesised in a series of reaction steps. Each heterocyclic ring and linker was coupled through solid phase chemistry using 2-(1H-benzotriazole-1-y1)-1,1,3,3-tetramethyluronium hexafluorophosphate (HBTU). Once the organic components were assembled, the platinum(II) group/s was/were added using either solid or solution phase chemistry. The polyamide sequence of PyPyPy-L4-ImImIm was designed to target the guanine rich telomere region of DNA. The metal complexes reported in this study will span sequences between 2, 5 or 7 DNA base pairs (depending on their length), which include 5'-(A/T)GGG(A/T)-3' and 5'-(A/T)(A/T)(A/T)GGG(A/T)-3'. All complexes were characterised using 1H and 195Pt NMR, high resolution mass spectrometry and elemental analysis. The binding of HLSP-6 and DNHLSP-6 to guanosine was also monitored by 1H NMR. / Doctor of Philosophy (PhD)
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