Дисертації з теми "Code distance"
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Ketkar, Avanti Ulhas. "Code constructions and code families for nonbinary quantum stabilizer code." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/2743.
Повний текст джерелаMiller, John. "High code rate, low-density parity-check codes with guaranteed minimum distance and stopping weight /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2003. http://wwwlib.umi.com/cr/ucsd/fullcit?p3090443.
Повний текст джерелаFilho, Nelson Whitaker. "Aircraft Distance Measurement System." International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/611674.
Повний текст джерелаThe Aircraft Distance Measurement System (ADMS) could be used in Flight Test application to determine the aircraft position and speed during takeoff, landing and acceleration-stop performance test within runway limits using a microwave link.
Nordström, Markus. "Automatic Source Code Classification : Classifying Source Code for a Case-Based Reasoning System." Thesis, Mittuniversitetet, Avdelningen för informations- och kommunikationssystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-25519.
Повний текст джерелаRivas, Angel Esteban Labrador. "Coordination of distance and overcurrent relays using a mathematical optimization technique." Universidade Estadual de Londrina. Centro de Tecnologia e Urbanismo. Programa de Pós-Graduação em Engenharia Elétrica, 2018. http://www.bibliotecadigital.uel.br/document/?code=vtls000218372.
Повний текст джерелаProtection of power transmission has an important role in power systems. To improve protection is common to combine different types of relays, which combination of overcurrent and distance relays is a well-known protection scheme. A slow operational speed of overcurrent relay forces application of distance relay as the main protection device. Overcurrent relays are used as backup protection to main distance protection system. To achieve this aim, coordination between primary and backup protection systems should be performed developing an objective function with both parameters. Speed, selectivity, and stability are constraints, which must be satisfied by performing coordination. The coordination of directional overcurrent relays (DOCRs) problem is a nonlinear programming problem (NLP), usually solved with a linear programming technique (LP) only considering the time dial setting (TDS) as a decision variable, without dealing with the non-linear problem of plug setting (PS), or solving the PS component using a heuristic technique. A metaheuristic algorithm method presented to solve the optimization problem is an ant colony optimization (ACO) algorithm. The ACO used is an extension of the ACO algorithm for continuous domain optimization problems implemented to mixed variable optimization problems, condensed in two types of variables both continuous and categorical. In this work, both TDS and PS are decision variables, TDS is considered continuous and PS categorical. Normally, the initial solution is random generated, in addition, those results are compared by using the same random PS values for solving a relaxation of the DOCRs problem with LP to obtain new TDS values. Including distance relays in the formulation will add an additional variable continuous type, but with linear (barely constant) characteristics making no changes in DOCRs formulation for this NLP problem. For this methodology, five transmission systems (3, 6, 8, 9, and 15 Bus accordingly) were evaluated to compare classical DOCR coordination, distance relays introduction and model response to high-quality initial solutions within a hybrid method using LP.
Toste, Marisa Lapa. "Distance properties of convolutional codes over Z pr." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17953.
Повний текст джерелаNesta tese consideramos códigos convolucionais sobre o anel polinomial [ ] r p ′ D , onde p é primo e r é um inteiro positivo. Em particular, focamo-nos no conjunto das palavras de código com suporte finito e estudamos as suas propriedades no que respeita às distâncias. Investigamos as duas propriedades mais importantes dos códigos convolucionais, nomeadamente, a distância livre e a distância de coluna. Começamos por analisar e solucionar o problema de, dado um conjunto de parâmetros, determinar a distância livre máxima possível que um código convolucional sobre [ ] r p ′ D pode atingir. Com efeito, obtemos um novo limite superior para esta distância generalizando os limites obtidos no contexto dos códigos convolucionais sobre corpos finitos. Além disso, mostramos que esse limite é ótimo, no sentido em que não pode ser melhorado. Para tal, apresentamos construções de códigos convolucionais (não necessariamente livres) que permitem atingir esse limite, para um certo conjunto de parâmetros. De acordo com a literatura chamamos a esses códigos MDS. Definimos também distâncias de coluna de um código convolucional. Obtemos limites superiores para as distâncias de coluna e chamamos MDP aos códigos cujas distâncias de coluna atingem estes limites superiores. Além disso, mostramos a existência de códigos MDP. Note-se, porém, que os códigos MDP apresentados não são completamente gerais pois os seus parâmetros devem satisfazer determinadas condições. Finalmente, estudamos o código dual de um código convolucional definido em (( )) r p ′ D . Os códigos duais de códigos convolucionais sobre corpos finitos foram exaustivamente investigados, como é refletido na literatura sobre o tema. Estes códigos são relevantes pois fornecem informação sobre a distribuição dos pesos do código e é neste sentido a inclusão deste assunto no âmbito desta tese. Outra razão importante para o estudo de códigos duais é a sua utilidade para o desenvolvimento de algoritmos de descodificação quando consideramos um erasure channel. Nesta tese são analisadas algumas propriedades fundamentais dos duais. Em particular, mostramos que códigos convolucionais definidos em (( )) r p ′ D admitem uma matriz de paridade. Para além disso, apresentamos um método construtivo para determinar um codificador de um código dual. keywords Convolutional codes, finite rings, free distance, column distance, MDS, MDP, dual code abstract In this thesis we consider convolutional codes over the polynomial ring [ ] r p ′ D , where p is a prime and r is a positive integer. In particular, we focus in the set of finite support codewords and study their distances properties. We investigate the two most important distance properties of convolutional codes, namely, the free distance and the column distance. First we address and fully solve the problem of determining the maximum possible free distance a convolutional code over [ ] r p ′ D can achieve, for a given set of parameters. Indeed, we derive a new upper bound on this distance generalizing the Singleton-type bounds derived in the context of convolutional codes over finite fields. Moreover, we show that such a bound is optimal in the sense that it cannot be improved. To do so we provide concrete constructions of convolutional codes (not necessarily free) that achieve this bound for any given set of parameters. In accordance with the literature we called such codes Maximum Distance Separable (MDS). We define the notion of column distance of a convolutional code. We obtain upper-bounds on the column distances and call Maximum Distance Profile (MDP) the codes that attain the maximum possible column distances. Furthermore, we show the existence of MDP codes. We note however that the MDP codes presented here are not completely general as their parameters need to satisfy certain conditions. Finally, we study the dual code of a convolutional code defined in (( )) r p ′ D . Dual codes of convolutional codes over finite fields have been thoroughly investigated as it is reflected in the large body of literature on this topic. They are relevant as they provide value information on the weight distribution of the code and therefore fit in the scope of this thesis. Another important reason for the study of dual codes is that they can be very useful for the development of decoding algorithms of convolutional codes over the erasure channel. In this thesis some fundamental properties have been analyzed. In particular, we show that convolutional codes defined in (( )) r p ′ D admit a parity-check matrix. Moreover, we
In this thesis we consider convolutional codes over the polynomial ring [ ] r p ′ D , where p is a prime and r is a positive integer. In particular, we focus in the set of finite support codewords and study their distances properties. We investigate the two most important distance properties of convolutional codes, namely, the free distance and the column distance. First we address and fully solve the problem of determining the maximum possible free distance a convolutional code over [ ] r p ′ D can achieve, for a given set of parameters. Indeed, we derive a new upper bound on this distance generalizing the Singleton-type bounds derived in the context of convolutional codes over finite fields. Moreover, we show that such a bound is optimal in the sense that it cannot be improved. To do so we provide concrete constructions of convolutional codes (not necessarily free) that achieve this bound for any given set of parameters. In accordance with the literature we called such codes Maximum Distance Separable (MDS). We define the notion of column distance of a convolutional code. We obtain upper-bounds on the column distances and call Maximum Distance Profile (MDP) the codes that attain the maximum possible column distances. Furthermore, we show the existence of MDP codes. We note however that the MDP codes presented here are not completely general as their parameters need to satisfy certain conditions. Finally, we study the dual code of a convolutional code defined in (( )) r p ′ D . Dual codes of convolutional codes over finite fields have been thoroughly investigated as it is reflected in the large body of literature on this topic. They are relevant as they provide value information on the weight distribution of the code and therefore fit in the scope of this thesis. Another important reason for the study of dual codes is that they can be very useful for the development of decoding algorithms of convolutional codes over the erasure channel. In this thesis some fundamental properties have been analyzed. In particular, we show that convolutional codes defined in (( )) r p ′ D admit a parity-check matrix. Moreover, we provide a constructive method to explicitly compute an encoder of the dual code.
Papadimitriou, Panayiotis D. "Code design based on metric-spectrum and applications." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1365.
Повний текст джерелаKacan, Denis, and Darius Sidlauskas. "Information Visualization and Machine Learning Applied on Static Code Analysis." Thesis, Blekinge Tekniska Högskola, Avdelningen för programvarusystem, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3033.
Повний текст джерелаMénéxiadis, Géraldine. "Détection à grande distance et localisation du supersonique "Concorde" à partir de signaux infrasonores." Phd thesis, Université de la Méditerranée - Aix-Marseille II, 2008. http://tel.archives-ouvertes.fr/tel-00487912.
Повний текст джерелаAbbara, Mamdouh. "Turbo-codes quantiques." Phd thesis, Ecole Polytechnique X, 2013. http://pastel.archives-ouvertes.fr/pastel-00842327.
Повний текст джерелаGrant, Eugene. "INTERCEPTOR TARGET MISSILE TELEMETRY." International Foundation for Telemetering, 1997. http://hdl.handle.net/10150/607598.
Повний текст джерелаA target missile is a unique piece of test hardware. This test tool must be highly reliable, low cost and simple and must perform any task that the developing interceptor missile planners require. The target missile must have ample power and guidance resources to put the target in a specified place in the sky at a desired time. The telemetry and measurement system for the target missile must have the same requirements as its interceptor missile but must be flexible enough to accept new requirements as they are applied to the target and its interceptor. The United States Army has tasked Coleman Aerospace to design and build this type of target missile. This paper describes and analyzes the telemetry and instrumentation system that a Hera target missile carries. This system has been flying for the past two years, has completed seven out of seven successful test flights and has accomplished all test objectives to date. The telemetry and instrumentation system is an integral part of the missile self-test system. All preflight checks and flight simulations are made with the on-board three-link telemetry system through a radio frequency (RF) link directly through the missile antenna system to a ground station antenna. If an RF transmission path is not available due to test range restrictions, a fiber-optic cable links the pulse code modulator (PCM) encoder to the receiving ground stations which include the bitsync, decommutator and recorders. With this capability, alternative testing is not limited by RF test range availability. The ground stations include two mobile stations and a factory station for all testing including preflight testing of the missile system prior to flight test launches. These three ground stations are built in a single configuration with additional equipment in the mobile units for use at remote locations. The design, fabrication, testing and utilization of these ground stations are reviewed. The telemetry system is a modification of the classical PCM system and will operate with its interceptor missile at least into the first decade from the year 2000.
Fang, Juing. "Décodage pondère des codes en blocs et quelques sujets sur la complexité du décodage." Paris, ENST, 1987. http://www.theses.fr/1987ENST0005.
Повний текст джерелаTujkovic, D. (Djordje). "Space-time turbo coded modulation for wireless communication systems." Doctoral thesis, University of Oulu, 2003. http://urn.fi/urn:isbn:9514269977.
Повний текст джерелаGharaei, Mohammad. "Nouveaux concepts pour les réseaux d'accès optiques." Paris, Télécom ParisTech, 2010. http://www.theses.fr/2010ENST0022.
Повний текст джерелаThis thesis deals with new concepts for future optical access networks. Firstly, optical private networking over PON is studied as it can potentially improve the QoS performance and security issue of conventional internet protocol based virtual private networks. A decentralized private networking traffic from PON traffic is a profitable approach to increase network throughput performance. We study the implementation of multiple optical private networks over PON layout using OCDMA technique via ring as well as star topology. The power budget and the network scalability of these architectures are analyzed and tested experimentally. These two architectures are demonstrated to have a negligible impact on the functionality of PON which proves the efficiency and the feasibility of simultaneous optical PNs over PON layout. Then, capacity performance of WDM/OCDMA networks is analyzed since hybrid networks are considered to improve multiplexing capacity of optical access networks. Physical layer limitations such as multiple access interference (MAI), beat noise and linear interchannel crosstalk are the major reasons for free error rate performance degradation. Crosstalk limitations have been evaluated to optimize user capacity performance. Then teletraffic capacity of WDM/OCDMA systems has been analyzed under the non-zero outage probability constraints to demonstrate a flexible capacity performance. Finally, it has been demonstrated that using WDM (de)multiplexers with lower crosstalk levels accompanying OCDMA encoders/decoders with good correlation properties, causes the teletraffic capacity to be closer to the nominal capacity
Zeh, Alexander. "Algebraic Soft- and Hard-Decision Decoding of Generalized Reed--Solomon and Cyclic Codes." Phd thesis, Ecole Polytechnique X, 2013. http://pastel.archives-ouvertes.fr/pastel-00866134.
Повний текст джерелаKandel, Khagendra. "A Preliminary Numerical Investigation of Heat Exchanger Piles." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1501858241480803.
Повний текст джерелаКравчук, Володимир Вікторович. "Комплекс програм для визначення нероздільних завадостійких кодів". Bachelor's thesis, КПІ ім. Ігоря Сікорського, 2020. https://ela.kpi.ua/handle/123456789/35023.
Повний текст джерелаThe bachelors project includes an explanatory note (97 pages, 41 drawings, 7 annexes). In this work, the topics of error correction and error detection coding, finding maximal clique of graph have been researched. Different types of coding were considered, the problem of analytic speed of code was described and Bron-Kerbosh algorithm was analyzed. Based on specifics of equivalents codes and Hamming graph the methods of algorithm optimization for finding maximal undivided error correcting code were suggested. It has been decided to develop a complex of program which will help to calculate and research error correcting codes. The concrete requirements and functionality for the complex were formulated: possibility to search maximal undivided error correcting code according to parameters provided by user, stop work of complex in the moment with saving intermediate data algorithm are working with, loading the saved data and continue work after algorithm had been stopped, the possibility to perform some operations with codes like compute the minimal code distance, compute minimal code distance between a word and a code, sort code, provide simple and understandable graphical user interface for comfortable working with program. The complex of programs is implemented by Java programming language which is supported by all the most popular operation systems using native library JavaFX for developing graphical user interface.
Khalid, Omar. "Quantum accuracy threshold for distance-5 codes." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101149.
Повний текст джерелаOuld, Cheikh Mouhamedou Youssouf. "On distance measurement methods for turbo codes." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100669.
Повний текст джерелаThe reliable determination of a code's error performance at very low error rates using simulations may take months or may not be practical at all. However, the knowledge of dmin and its multiplicities can be used to estimate the error rates at high SNR. This thesis is concerned with efficient and accurate distance measurement methods for turbo codes. Since high values of dmin can be caused by high input weight values, say up to 20 or higher, if a brute force algorithm is used the accurate determination of dmin requires that all possible input sequences of input weight up to 20 be tested. Testing all possible input sequences becomes impractical as the size of the interleaver and the value of input weight increase. Thus, the accurate determination of the distance spectrum, or at least dmin and its multiplicities, is a significant problem, especially for interleavers that yield high dmin. Based on Garello's true distance measurement method, this thesis presents an efficient and accurate distance measurement method for single- and double-binary turbo codes that uses proper trellis termination such as dual-termination or tail-biting. This method is applied to determine the distance spectra for the digital video broadcasting with return channel via satellite (DVB-RCS) standard double-binary turbo codes. It is also used to design new interleavers for DVB-RCS that yield a significant improvement in error performance compared to those in the standard.
This method fits particularly well with tail-biting turbo codes that use structured interleavers. This is because the distance properties repeat and this method can use this knowledge to reduce the search space. The reduction in search space results in significant reduction in complexity (i.e., execution time), which allows the determination of high dmin values in reasonable time. This efficiency is demonstrated for both single- and double-binary turbo codes, using structured interleavers that have high dmin values for various code rates. This method reduces the execution tunes by a factor of 40 to 400.
Sims, Kristian Brian. "Orientable Single-Distance Codes for Absolute Incremental Encoders." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/9067.
Повний текст джерелаZeng, Fanxuan. "Nonlinear codes: representation, constructions, minimum distance computation and decoding." Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/284241.
Повний текст джерелаBilal, Muhammad. "Codes over rings: maximum distance separability and self-duality." Doctoral thesis, Universitat Autònoma de Barcelona, 2012. http://hdl.handle.net/10803/107703.
Повний текст джерелаBounds on the size of a code are an important part of coding theory. One of the fundamental problems in coding theory is to find a code with largest possible distance d. Researchers have found different upper and lower bounds on the size of linear and nonlinear codes e.g., Plotkin, Johnson, Singleton, Elias, Linear Programming, Griesmer, Gilbert and Varshamov bounds. In this dissertation we have studied the Singleton bound, which is an upper bound on the minimum distance of a code, and have defined maximum distance separable (MDS) Z2Z4 additive codes. Two different forms of these bounds are presented in this work where we have characterized all maximum distance separable Z2Z4-additive codes with respect to the Singleton bound (MDSS) and strong conditions are given for maximum distance separable Z2Z4-additive codes with respect to the rank bound (MDSR). Generation of new codes has always been an interesting topic, where one can study the properties of these newly generated codes and establish new results. Self-dual codes are an important class of codes. There are numerous constructions of self-dual codes from combinatorial objects. In this work we have given two methods for generating self-dual codes from 3-class association schemes, namely pure construction and bordered construction. Binary self-dual codes are generated by using these two methods from non-symmetric 3-class association schemes and self-dual codes from rectangular association schemes are generated over Zk. Borges, Dougherty and Fernández-Córdoba in 2011 presented a method to generate new Z2Z4-additive self-dual codes from the existing Z2Z4-additive selfdual codes by extending their length. In this work we have verified whether properties like separability, antipodality and code Type are retained or not, when using this method.
King, Ian David. "Light-cone and short distance aspects of nucleon wavefunctions." Thesis, University of Southampton, 1986. https://eprints.soton.ac.uk/393993/.
Повний текст джерелаWoungang, Isaac. "Distances minimales de certains codes quasi cycliques." Toulon, 1994. http://www.theses.fr/1994TOUL0004.
Повний текст джерелаChan, Evelyn Yu-San. "Heuristic optimisation for the minimum distance problem." Thesis, Nottingham Trent University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324569.
Повний текст джерелаHarney, Isaiah H. "Colorings of Hamming-Distance Graphs." UKnowledge, 2017. http://uknowledge.uky.edu/math_etds/49.
Повний текст джерелаKumar, Santosh. "Upper bounds on minimum distance of nonbinary quantum stabilizer codes." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/2744.
Повний текст джерелаCadic, Emmanuel. "Construction de Turbo Codes courts possédant de bonnes propriétés de distance minimale." Limoges, 2003. http://aurore.unilim.fr/theses/nxfile/default/2c131fa5-a15a-4726-8d49-663621bd2daf/blobholder:0/2003LIMO0018.pdf.
Повний текст джерелаThis thesis is aimed at building turbo codes with good minimum distances and delaying the``error-floor'' which corespond to a threshold of 10-6 for the binary error rate. Under this threshold, the slope of the curve decreases significantly. This problem is alleviated by the use of duo-binary turbo codes [11] which guarantee better minimum distances. In order to obtain good minimum distances with short turbo codes (length inferior to 512), the first construction used and studied is the one proposed by Carlach and Vervoux [26]. It allows to obtain very good minimum distances but its decoding is unfortunately very difficult because of its structure. After identifying the reasons for this problem, we have modified these codes by using some graphicals structures which are the gathering of low complexity components codes. The idea is to realize this change without loosing the minimum distances properties, and consequently we had to understand why minimum distances are good for this familly of codes and define a new criteria to choose ``good'' components codes. This criteria is independent from the minimum distance of the component codes because it is derived from the Input-Output Weight Enumerator (IOWE) of the components codes. It allows us to choose components codes with very low complexity which are combined in order to provide 4-state tail-biting trellises. These trellises are then used to build multiple parallel concatenated and serial turbo codes with good minimum distances. Some extremal self-dual codes have been built in that way
Aghaei, Morteza. "Near maximum distance separable codes over the field of eleven elements." Thesis, University of Sussex, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418400.
Повний текст джерелаMoustrou, Philippe. "Geometric distance graphs, lattices and polytopes." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0802/document.
Повний текст джерелаA distance graph G(X;D) is a graph whose set of vertices is the set of points X of a metric space (X; d), and whose edges connect the pairs fx; yg such that d(x; y) 2 D. In this thesis, we consider two problems that may be interpreted in terms of distance graphs in Rn. First, we study the famous sphere packing problem, in relation with thedistance graph G(Rn; (0; 2r)) for a given sphere radius r. Recently, Venkatesh improved the best known lower bound for lattice sphere packings by a factor log log n for infinitely many dimensions n. We prove an effective version of this result, in the sense that we exhibit, for the same set of dimensions, finite families of lattices containing a lattice reaching this bound. Our construction uses codes over cyclotomic fields, lifted to lattices via Construction A. We also prove a similar result for families of symplectic lattices. Second, we consider the unit distance graph G associated with a norm k _ k. The number m1 (Rn; k _ k) is defined as the supremum of the densities achieved by independent sets in G. If the unit ball corresponding with k _ k tiles Rn by translation, then it is easy to see that m1 (Rn; k _ k) > 1 2n . C. Bachoc and S. Robins conjectured that the equality always holds. We show that this conjecture is true for n = 2 and for several Voronoï cells of lattices in higher dimensions, by solving packing problems in discrete graphs
Gustavsson, Hans-Olof. ""Utan bok är det ingen riktig undervisning" : En studie av skolkulturella referensramar i sfi." Doctoral thesis, Stockholms universitet, Institutionen för undervisningsprocesser, kommunikation och lärande (UKL), 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7113.
Повний текст джерелаBazzi, Louay Mohamad Jamil 1974. "Minimum distance of error correcting codes versus encoding complexity, symmetry, and pseudorandomness." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/17042.
Повний текст джерелаIncludes bibliographical references (leaves 207-214).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
We study the minimum distance of binary error correcting codes from the following perspectives: * The problem of deriving bounds on the minimum distance of a code given constraints on the computational complexity of its encoder. * The minimum distance of linear codes that are symmetric in the sense of being invariant under the action of a group on the bits of the codewords. * The derandomization capabilities of probability measures on the Hamming cube based on binary linear codes with good distance properties, and their variations. Highlights of our results include: * A general theorem that asserts that if the encoder uses linear time and sub-linear memory in the general binary branching program model, then the minimum distance of the code cannot grow linearly with the block length when the rate is nonvanishing. * New upper bounds on the minimum distance of various types of Turbo-like codes. * The first ensemble of asymptotically good Turbo like codes. We prove that depth-three serially concatenated Turbo codes can be asymptotically good. * The first ensemble of asymptotically good codes that are ideals in the group algebra of a group. We argue that, for infinitely many block lengths, a random ideal in the group algebra of the dihedral group is an asymptotically good rate half code with a high probability. * An explicit rate-half code whose codewords are in one-to-one correspondence with special hyperelliptic curves over a finite field of prime order where the number of zeros of a codeword corresponds to the number of rational points.
(cont.) * A sharp O(k-1/2) upper bound on the probability that a random binary string generated according to a k-wise independent probability measure has any given weight. * An assertion saying that any sufficiently log-wise independent probability measure looks random to all polynomially small read-once DNF formulas. * An elaborate study of the problem of derandomizability of AC₀ by any sufficiently polylog-wise independent probability measure. * An elaborate study of the problem of approximability of high-degree parity functions on binary linear codes by low-degree polynomials with coefficients in fields of odd characteristics.
by Louay M.J. Bazzi.
Ph.D.
Baldiwala, Aliasgar M. "Distance Distribution and Error Performance of Reduced Dimensional Circular Trellis Coded Modulation." Ohio University / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1079387217.
Повний текст джерелаSiap, Irfan. "Generalized [Gamma]-fold weight enumerators for linear codes and new linear codes with improved minimum distances /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488193272067477.
Повний текст джерелаLuna, Ricardo, and Hrishikesh Tapse. "An Analysis on the Coverage Distance of LDPC-Coded Free-Space Optical Links." International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606240.
Повний текст джерелаWe design irregular Low-Density Parity-Check (LDPC) codes for free-space optical (FSO) channels for different transmitter-receiver link distances and analyze the error performance for different atmospheric conditions. The design considers atmospheric absorption, laser beam divergence, and random intensity fluctuations due to atmospheric turbulence. It is found that, for the same transmit power, a system using the designed codes works over much longer link distances than a system that employs regular LDPC codes. Our analysis is particularly useful for portable optical transceivers and mobile links.
Ahmed, Naveed, and Waqas Ahmed. "Classification of perfect codes and minimal distances in the Lee metric." Thesis, Linnaeus University, School of Computer Science, Physics and Mathematics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-6574.
Повний текст джерелаPerfect codes and minimal distance of a code have great importance in the study of theoryof codes. The perfect codes are classified generally and in particular for the Lee metric.However, there are very few perfect codes in the Lee metric. The Lee metric hasnice properties because of its definition over the ring of integers residue modulo q. It isconjectured that there are no perfect codes in this metric for q > 3, where q is a primenumber.The minimal distance comes into play when it comes to detection and correction oferror patterns in a code. A few bounds on the number of codewords and minimal distanceof a code are discussed. Some examples for the codes are constructed and their minimaldistance is calculated. The bounds are illustrated with the help of the results obtained.
Edsborg, Karin. "Color Coded Depth Information in Medical Volume Rendering." Thesis, Linköping University, Department of Science and Technology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1823.
Повний текст джерелаContrast-enhanced magnetic resonance angiography (MRA) is used to obtain images showing the vascular system. To detect stenosis, which is narrowing of for example blood vessels, maximum intensity projection (MIP) is typically used. This technique often fails to demonstrate the stenosis if the projection angle is not suitably chosen. To improve identification of this region a color-coding algorithm could be helpful. The color should be carefully chosen depending on the vessel diameter.
In this thesis a segmentation to produce a binary 3d-volume is made, followed by a distance transform to approximate the Euclidean distance from the centerline of the vessel to the background. The distance is used to calculate the smallest diameter of the vessel and that value is mapped to a color. This way the color information regarding the diameter would be the same from all the projection angles.
Color-coded MIPs, where the color represents the maximum distance, are also implemented. The MIP will result in images with contradictory information depending on the angle choice. Looking in one angle you would see the actual stenosis and looking in another you would see a color representing the abnormal diameter.
Mahmudi, Ali. "The investigation into generic VHDL implementation of generalised minimum distance decoding for Reed Solomon codes." Thesis, University of Huddersfield, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417302.
Повний текст джерелаMykhaylyk, O. O. "Structural Characterization of Colloidal Core-shell Polymer-based Nanoparticles Using Small-angle X-ray Scattering." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/34779.
Повний текст джерелаAlkhonini, Omar Ahmed. "CODA CONSONANT CLUSTER PATTERNS IN THE ARABIC NAJDI DIALECT." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/theses/1368.
Повний текст джерелаGaland, Fabien. "Construction de codes Z indice p à la puissance k linéaires de bonne distance minimale et schémas de dissimulation fondés sur les codes de recouvrement." Caen, 2004. http://www.theses.fr/2004CAEN2047.
Повний текст джерелаVaka, Kranthi, and Karthik Narla. "The impact of maturity, scale and distribution on software quality : An industrial case study." Thesis, Blekinge Tekniska Högskola, Institutionen för programvaruteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-15626.
Повний текст джерелаSengupta, Avik. "Redundant residue number system based space-time block codes." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/14111.
Повний текст джерелаDepartment of Electrical and Computer Engineering
Balasubramaniam Natarajan
Space-time coding (STC) schemes for Multiple Input Multiple Output (MIMO) systems have been an area of active research in the past decade. In this thesis, we propose a novel design of Space-Time Block Codes (STBCs) using Redundant Residue Number System (RRNS) codes, which are ideal for high data rate communication systems. Application of RRNS as a concatenated STC scheme to a MIMO wireless communication system is the main motivation for this work. We have optimized the link between residues and complex constellations by incorporating the “Direct Mapping” scheme, where residues are mapped directly to Gray coded constellations. Knowledge of apriori probabilities of residues is utilized to implement a probability based “Distance-Aware Direct Mapping” (DA) scheme, which uses a set-partitioning approach to map the most probable residues such that they are separated by the maximum possible distance. We have proposed an “Indirect Mapping” scheme, where we convert the residues back to bits before mapping them. We have also proposed an adaptive demapping scheme which utilizes the RRNS code structure to reduce the ML decoding complexity and improve the error performance. We quantify the upper bounds on codeword and bit error probabilities of both Systematic and Non-systematic RRNS-STBC and characterize the achievable coding and diversity gains assuming maximum likelihood decoding (MLD). Simulation results demonstrate that the DA Mapping scheme provides performance gain relative to a Gray coded direct mapping scheme. We show that Systematic RRNS-STBC codes provide superior performance compared to Nonsystematic RRNS-STBC, for the same code parameters, owing to more efficient binary to residue mapping. When compared to other concatenated STBC and Orthogonal STBC (OSTBC) schemes, the proposed system gives better performance at low SNRs.
Bogaerts, Mathieu. "Codes et tableaux de permutations, construction, énumération et automorphismes." Doctoral thesis, Universite Libre de Bruxelles, 2009. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210302.
Повний текст джерелаUn code de permutations G(n,d) un sous-ensemble C de Sym(n) tel que la distance de Hamming D entre deux éléments de C est supérieure ou égale à d. Dans cette thèse, le groupe des isométries de (Sym(n),D) est déterminé et il est prouvé que ces isométries sont des automorphismes du schéma d'association induit sur Sym(n) par ses classes de conjugaison. Ceci mène, par programmation linéaire, à de nouveaux majorants de la taille maximale des G(n,d) pour n et d fixés et n compris entre 11 et 13. Des algorithmes de génération avec rejet d'objets isomorphes sont développés. Pour classer les G(n,d) non isométriques, des invariants ont été construits et leur efficacité étudiée. Tous les G(4,3) et les G(5,4) ont été engendrés à une isométrie près, il y en a respectivement 61 et 9445 (dont 139 sont maximaux et décrits explicitement). D’autres classes de G(n,d) sont étudiées.
A permutation code G(n,d) is a subset C of Sym(n) such that the Hamming distance D between two elements of C is larger than or equal to d. In this thesis, we characterize the isometry group of the metric space (Sym(n),D) and we prove that these isometries are automorphisms of the association scheme induced on Sym(n) by the conjugacy classes. This leads, by linear programming, to new upper bounds for the maximal size of G(n,d) codes for n and d fixed and n between 11 and 13. We develop generating algorithms with rejection of isomorphic objects. In order to classify the G(n,d) codes up to isometry, we construct invariants and study their efficiency. We generate all G(4,3) and G(4,5)codes up to isometry; there are respectively 61 and 9445 of them. Precisely 139 out of the latter codes are maximal and explicitly described. We also study other classes of G(n,d)codes.
Doctorat en sciences, Spécialisation mathématiques
info:eu-repo/semantics/nonPublished
Console, Sarah. "Disturbi Specifici di Apprendimento: come la didattica a distanza influenza l'apprendimento della matematica." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20893/.
Повний текст джерелаChen, Changlin. "The performance analysis and decoding of high dimensional trellis-coded modulation for spread spectrum communications." Ohio : Ohio University, 1997. http://www.ohiolink.edu/etd/view.cgi?ohiou1174616331.
Повний текст джерелаYang, Zhen-Dong, and 楊振東. "The Distance of Cyclic Code." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/72140275379208257516.
Повний текст джерелаChu, Ya-chi, and 祝亞琪. "USING NORMALIZED GOOGLE DISTANCE TO REFINE CODE SEARCH RESULTS." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/90838642351194086617.
Повний текст джерела國立中央大學
資訊管理研究所
98
With the popularity of open source software, many people have the willing to share their projects via internet. In order to enhance the efficiency of software production, program developers try to search the existing open source software on the web. Therefore a new internet service, code search engine, emerged from the network. Although search engines provide a convenient way to assist developers to reuse the existing Application Programming Interfaces, the search results obtained from the search engines do not always satisfy the requirement of developers. Numerous and complex search results make developers hard to reuse the code quickly. We proposed a system architecture which is able to solve the problem we mention above: First, we store the related data which is extracted from the search results of Koders in the local repository. Second, we convert every file into the abstract syntax tree format to get the structural data. Third, we cluster and compute every file’s normalized Google distance value through the structural data. And then we will re-rank the search results according to the Google distance value. Four, we will give some semantic tags to each cluster and hope it can help user to find the right cluster quickly. Finally, we use precision and recall value as an index to evaluate the proposed system architecture’s performance about clustering. Furthermore, we also use a case to explain whether the proposed system architecture can effectively help developers to find the useful source code, and compare with related academic research.
Sun, Shih-Hung, and 孫士烘. "Compare the similarity of C source code using Edit-Distance." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/16239559813427360013.
Повний текст джерела中原大學
資訊工程研究所
90
The differences of source codes are compared by people for a long time , and the useful tools we can find is Diff. But Diff didn’t compare the syntax of source code and get the minimal difference. If we change the source code’s parameters name to difference then we will get difference result from Diff. This small change can be judged by people but without by computer. And these source codes will cost many time to judge. We started to analysis the difference of C source code using Edit-Distance for this state. In this thesis, we design a comparative system to rewrite the syntax of the same means but different expression because their cost of time and space are the same. And we deal with the space’s problems and transduce source codes to temporal files. Then we rewrite file according the code’s data flow, variable’s dependence , and code’s relationship to get the minimal Edit-Distance. Finally , we use string’s match algorithm to get the minimal Edit-Distance ( the source code’s similarity ) to find the same C source code.
Wang, Chih-Kang, and 王志剛. "Minimum Distance Optimization on Signature Code for Uplink Non-orthogonal Multiple Access." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/6u6g64.
Повний текст джерела國立清華大學
通訊工程研究所
107
This thesis studies the design of signature code to support non-orthogonal multiple access (NOMA), called signature coded multiple access (SIGMA). In the current orthogonal frequency division multiple access (OFDMA) system, the number of connection is limited by the number of available resource element. Also, both the scheduling latency and power consumption of the OFDMA system are too high. In SIGMA, each user chooses the codeword from the signature code book, and shares the same time-frequency resources for multiple access. By doing so, SIGMA can allow high user overloading ratio. In grant free SIGMA scheme, which will predefine a contention region let users to share this region. By the predefined contention region, the network does not need to send the control signaling (SG) and the access user does not need to send the scheduling grant signal (SR). The SIGMA scheme constructs the signature code matrix with minimum distance maximization to improve the error performance in multiple access channel. According our design idea, SIGMA uses the suboptimal signature code matrix as codebook for non-orthogonal multiple access. Our results show that SIGMA can achieve better ABER performance than Sparse code multiple access (SCMA) and Multi-user shared access (MUSA).