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1

Scott, Davidson Arthur. "Cost and performance impacts of optical amplifier technology on fiber-optic communication networks." Master's thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-02162010-020236/.

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2

Venter, Petrus Johannes. "Feasibility of CMOS optical clock distribution networks." Diss., University of Pretoria, 2009. http://hdl.handle.net/2263/26440.

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CMOS is well known for its ability to scale. This fact is reflected in the aggressive scaling on a continual basis from the invention of CMOS up to date. As devices are scaled, device performance improves due to shorter channel lengths and more densely packed functions for the same amount of area. In recent years, however, the performance gain obtained through scaling has begun to suffer under the degradation of the associate interconnect performance. As devices become smaller, interconnects need to follow. Unlike transistors, the scaling of interconnects results in higher capacitances and resistances, thereby limiting overall system performance. Trying to alleviate the delay effects results in increased power consumption, especially in global structures such as clock distribution networks. A possible solution to this problem is the use of optical interconnects, which are fast and much less lossy than the electrical equivalents. This dissertation describes an investigation on what future technology nodes will entail in terms of power consumption of clock networks, and what is required for an optical alternative to become feasible. A common clock configuration is used as a basis for comparison, where both electrical and optical networks are designed to component level. Optimisation is done on both to ensure a reasonable comparison, and the results of the respective power consumption components are then compared in order to find the criteria for a feasible optical clock distribution scheme. Copyright<br>Dissertation (MEng)--University of Pretoria, 2009.<br>Electrical, Electronic and Computer Engineering<br>unrestricted
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3

Pimpalkhare, Mangesh S. "Linearly repeatered communication systems using optical amplifiers." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-05042010-020243/.

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4

O'Byrne, V. A. "Optical communications : FSK repeatered transmission using an injection locked laser." Thesis, Bangor University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380028.

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5

Wang, Y. "Linecoded digital pulse position modulation for repeatered optical fibre telecommunications." Thesis, University of Essex, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376832.

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6

Ozadam, Hakan. "Repeated-root Cyclic Codes And Matrix Product Codes." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615304/index.pdf.

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We study the Hamming distance and the structure of repeated-root cyclic codes, and their generalizations to constacyclic and polycyclic codes, over finite fields and Galois rings. We develop a method to compute the Hamming distance of these codes. Our computation gives the Hamming distance of constacyclic codes of length $np^s$ in many cases. In particular, we determine the Hamming distance of all constacyclic, and therefore cyclic and negacyclic, codes of lengths p^s and 2p^s over a finite field of characteristic $p$. It turns out that the generating sets for the ambient space obtained by torsional degrees and strong Groebner basis for the ambient space are essentially the same and one can be obtained from the other. In the second part of the thesis, we study matrix product codes. We show that using nested constituent codes and a non-constant matrix in the construction of matrix product codes with polynomial units is a crucial part of the construction. We prove a lower bound on the Hamming distance of matrix product codes with polynomial units when the constituent codes are nested. This generalizes the technique used to construct the record-breaking examples of Hernando and Ruano. Contrary to a similar construction previously introduced, this bound is not sharp and need not hold when the constituent codes are not nested. We give a comparison of this construction with a previous one. We also construct new binary codes having the same parameters, of the examples of Hernando and Ruano, but non-equivalent to them.
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7

Öhlén, Peter. "Transmisison limitations of 2R reshaping repeaters and applications of high-speed wavelength conversion in optical networking." Doctoral thesis, KTH, Electronic Systems Design, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2992.

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8

Cole, James Jacob. "Assessing Nonlinear Relationships through Rich Stimulus Sampling in Repeated-Measures Designs." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/dissertations/1587.

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Explaining a phenomenon often requires identification of an underlying relationship between two variables. However, it is common practice in psychological research to sample only a few values of an independent variable. Young, Cole, and Sutherland (2012) showed that this practice can impair model selection in between-subject designs. The current study expands that line of research to within-subjects designs. In two Monte Carlo simulations, model discrimination under systematic sampling of 2, 3, or 4 levels of the IV was compared with that under random uniform sampling and sampling from a Halton sequence. The number of subjects, number of observations per subject, effect size, and between-subject parameter variance in the simulated experiments were also manipulated. Random sampling out-performed the other methods in model discrimination with only small, function-specific costs to parameter estimation. Halton sampling also produced good results but was less consistent. The systematic sampling methods were generally rank-ordered by the number of levels they sampled.
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9

Mungan, Murat Can. "Optimal Procedures in Criminal Law: Five Essays." Thesis, Boston College, 2010. http://hdl.handle.net/2345/1744.

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Thesis advisor: Hideo Konishi<br>Becker (1968) provides a formal framework for analyzing various policies in criminal law. Within this framework there are potential criminals, who have varying benefits from committing an illegal act. They are subject to sanctions when they are caught and are found guilty for committing such acts. Accordingly, increased expected sanctions lead to greater deterrence. There are also costs associated with achieving such deterrence. Hence, there are optimal policy variables which balance costs and gains associated with increased deterrence. In my dissertation, in five independent but closely related essays, I address various issues related to criminal law by making use of optimal crime and deterrence models, which are similar to Becker (1968). First, I analyze the standard of proof in criminal trials and extend a justification as to why there are higher standards of proof in criminal trials versus civil trials. Next, I introduce the concept of mixed warning strategies, and justify the use of mixed as well as pure warning strategies in law enforcement. In a related essay, I show that it is optimal to punish repeat offenders more severely than first time offenders, provided that offenders gain experience in evading detection by committing offenses. In my fourth essay, I identify reasons as to why it is welfare improving to allow individuals to self-report conduct crimes. Finally, I propose a simple framework to incorporate the concept of remorse in the economic analysis of criminal law, and show that the Beckerian maximal fine result need not hold when some individuals feel remorse<br>Thesis (PhD) — Boston College, 2010<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Economics
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10

Walkenhorst, Brett T. "Achieving near-optimal MIMO capacity in a rank-deficient LOS environment." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29672.

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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.<br>Committee Chair: Ingram, Mary Ann; Committee Member: Durgin, Greg; Committee Member: Kenney, Steve; Committee Member: Landgren, Jack; Committee Member: Li, Ye. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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11

Xu, Ping. "Evaluation of Repeated Biomarkers: Non-parametric Comparison of Areas under the Receiver Operating Curve Between Correlated Groups Using an Optimal Weighting Scheme." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4261.

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Receiver Operating Characteristic (ROC) curves are often used to evaluate the prognostic performance of a continuous biomarker. In a previous research, a non-parametric ROC approach was introduced to compare two biomarkers with repeated measurements. An asymptotically normal statistic, which contains the subject-specific weights, was developed to estimate the areas under the ROC curve of biomarkers. Although two weighting schemes were suggested to be optimal when the within subject correlation is 1 or 0 by the previous study, the universal optimal weight was not determined. We modify this asymptotical statistic to compare AUCs between two correlated groups and propose a solution to weight optimization in non-parametric AUCs comparison to improve the efficiency of the estimator. It is demonstrated how the Lagrange multiplier can be used as a strategy for finding the weights which minimize the variance function subject to constraints. We show substantial gains of efficiency by using the novel weighting scheme when the correlation within group is high, the correlation between groups is high, and/or the disease incidence is small, which is the case for many longitudinal matched case-control studies. An illustrative example is presented to apply the proposed methodology to a thyroid function dataset. Simulation results suggest that the optimal weight performs well with a sample size as small as 50 per group.
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12

Li, Xiaoxi. "Contributions à l'étude des propriétés asymptotiques en contrôle optimal et en jeux répétés." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066231/document.

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Cette thèse étudie des propriétés limites de problèmes de contrôle optimal (un joueur, en temps continu) et de jeux répétés à somme nulle (à deux joueurs, en temps discret) avec horizon tendant vers l'infini. Plus précisément, nous étudions la convergence de la fonction valeur lorsque la durée du problème de contrôle ou la répétition du jeu tend vers l'infini (analyse asymptotique), et l'existence de stratégies robustes, i.e. des stratégies ԑ-optimales pour guarantir la valeur limite dans tous les problèmes de contrôle de durée suffisamment longue ou dans tous les jeux répétés de répétition suffisamment large (analyse uniforme). La partie sur le contrôle optimal est composée de trois chapitres. Le chapitre 2 est un article de présentation de la littérature récente sur les propriétés à long terme dans divers modèles d'optimisation dynamique. Dans les deux chapitres suivants, nous nous concentrons sur les problèmes de contrôle optimal où le coȗt de la trajectoire est évalué par une mesure de probabilité générale sur R_+, au lieu de la moyenne de T-horizon (moyenne de Cesàro) ou de la λ-escompté (moyenne d'Abel). Dans le chapitre 3, nous introduisons une condition de régularité asymptotique pour une suite de mesures de probabilité sur R_+ induisant un horizon tendant vers l'infini (en particulier, T tendant vers l'infini ou λ tendant vers zéro). Nous montrons que pour toute suite d'évaluations satisfaisant cette condition, la suite associée des valeurs du problème de contrôle converge uniformément si et seulement si cette suite est totalement bornée pour la norme uniforme. On en déduit que pour des problèmes de contrôle définis sur un domaine invariant compact et vérifiant une certaine condition de non-expansivité, la fonction valeur définie par une mesure de probabilité générale converge quand l'évaluation devient suffisamment régulière. En outre, nous prouvons dans le chapitre 4 que sous les mȇmes conditions de compacité et de non-expansivité, il existe des contrôles ԑ-optimaux pour tous les problèmes où le coȗt de la trajectoire est évalués par une mesure de probailité suffisamment régulières. La partie sur les jeux répétés se compose de deux chapitres. Le chapitre 5 est consacré à l'étude d'une sous-classe de jeux absorbants à information incomplète d'un côté. Le modèle que nous considérons est une généralisation du Big match à information incomplète d'un côté introduit par Sorin (1984). Nous démontrons l'existence de la valeur limite, du Maxmin, du Minmax, et l'égalité du Maxmin et de la valeur limite. Dans le chapitre 6, nous établissons plusieurs résultats concernant des jeux récursifs. Nous considérons d'abord les jeux récursifs avec un espace dénombrable d'états et prouvons que si la famille des fonctions valeur des jeux à n étapes est totalement bornée pour la norme uniforme, alors la valeur uniforme existe. En particulier, la convergence uniforme des valeurs des jeux à n étapes implique la convergence uniforme des valeurs des jeux escomptés. à l'aide d'un résultat dans Rosenberg et Vieille (2000), on en déduit un théorème taubérien uniforme pour les jeux récursifs. Deuxièmement, nous appliquons le résultat d'existence de la valeur uniforme à une classe des modèles général de jeux répétés et nous prouvons que la valeur limite et le Maxmin existent et sont égaux. Ces jeux répétés sont des jeux récursifs avec signaux où le joueur 1 peut toujours déduire le signal du joueur 2 de son propre signal<br>This dissertation studies limit properties in optimal control problems (one-player, in continuous time) and in zero-sum repeated games (two-player, in discrete time) with large horizons. More precisely, we investigate the convergence of the value function when the duration of the control problem or the repetition of the game tends to infinity (the asymptotic analysis), and the existence of robust strategies, i.e. ԑ-optimal strategies to guarantee the limit value in all control problems with sufficiently long durations or in all repeated games with sufficiently large repetitions (the uniform analysis). The part on optimal control is composed of three chapters. Chapter 2 is a survey article on recent literature of long-term properties in various models of dynamic optimization. In the following two chapters, we focus on optimal control problems where the running cost is evaluated by a general probability measure, instead of the usual T-horizon average (Cesàro mean) or the λ-discount (Abel mean). In Chapter 3, we introduce an asymptotic regularity condition for a sequence of probability measures on positive real numbers which induces a horizon tending to infinity (in particular T tending to infinity or λ tending to zero) for the control problem. We prove that for any sequence of evaluations satisfying this condition, the associated sequence of value function of the control problem converges uniformly if and only if this sequence is totally bounded for the uniform norm. We deduce that for control problems defined on a compact invariant domain and satisfying some non expansive condition, the value function defined by a general probability measure converges as the evaluation becomes sufficiently regular. Further, we prove in Chapter 4 that under the same compact and non expansive conditions, there exist ԑ-optimal controls for all problems where the running cost is evaluated by a sufficiently regular probability measure. The part on repeated games consists of two chapters. Chapter 5 is devoted to the study of a subclass of absorbing games with one-sided incomplete information. The model we consider is a generalization of Big match with one-sided incomplete information introduced by Sorin (1984). We prove the existence of the limit value, Maxmin, Minmax, and that Maxmin is equal to the limit value. In Chapter 6, we establish several results for recursive games. We first consider recursive games with a countable state space and prove that if the family of n-stage value functions is totally bounded for the uniform norm, then the uniform value exists. In particular, the uniform convergence of n-stage values implies the uniform convergence of λ-discounted values. Combined with a result in Rosenberg and Vieille (2000), we deduce a uniform Tauberian theorem for recursive games. Second, we use the existence result of uniform value to a class of the generalized models of repeated games and prove that both the limit value and Maxmin exist and are equal. This class of repeated games are recursive games with signals where player 1 can always deduce the signal of player 2 from his own along the play
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13

Jen, Hsiang-Hua. "Theory of light-matter interactions in cascade and diamond type atomic ensembles." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37288.

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In this thesis, we investigate the quantum mechanical interaction of light with matter in the form of a gas of ultracold atoms: the atomic ensemble. We present a theoretical analysis of two problems, which involve the interaction of quantized electromagnetic fields (called signal and idler) with the atomic ensemble (i) cascade two-photon emission in an atomic ladder configuration, and (ii) photon frequency conversion in an atomic diamond configuration. The motivation of these studies comes from potential applications in long-distance quantum communication where it is desirable to generate quantum correlations between telecommunication wavelength light fields and ground level atomic coherences. In the two systems of interest, the light field produced in the upper arm of an atomic Rb level scheme is chosen to lie in the telecom window. The other field, resonant on a ground level transition, is in the near-infrared region of the spectrum. Telecom light is useful as it minimizes losses in the optical fiber transmission links of any two long-distance quantum communication device. We develop a theory of correlated signal-idler pair correlation. The analysis is complicated by the possible generation of multiple excitations in the atomic ensemble. An analytical treatment is given in the limit of a single excitation assuming adiabatic laser excitations. The analysis predicts superradiant timescales in the idler emission in agreement with experimental observation. To relax the restriction of a single excitation, we develop a different theory of cascade emission, which is solved by numerical simulation of classical stochastic differential equation using the theory of open quantum systems. The simulations are in good qualitative agreement with the analytical theory of superradiant timescales. We further analyze the feasibility of this two-photn source to realize the DLCZ protocol of the quantum repeater communication system. We provide a quantum theory of near-infrared to telecom wavelength conversion in the diamond configuration. The system provides a crucial part of a quantum-repeater memory element, which enables a "stored" near-infrared photon to be converted to a telecom wavelength for transmission without the destruction of light-atom quantum correlation. We calculate the theoretical conversion efficiency, analyzing the role of optical depth of the ensemble, pulse length, and quantum fluctuations on the process.
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14

Issautier, Amandine. "Préparation et manipulation d'un nuage d'atomes froids de rubidium pour le stockage de l'information quantique." Thesis, Nice, 2014. http://www.theses.fr/2014NICE4097/document.

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La communication quantique vise la génération, la distribution et le stockage de qubits afin d'établir de véritables réseaux quantiques. Le stockage cohérent, efficace et réversible d'états photoniques dans des mémoires atomiques est donc nécessaire et représente actuellement un enjeu majeur de la science de l'information quantique. Ainsi, de nombreux supports de stockage, tels que les ensembles d'atomes froids ou à l'état solide, sont envisagés afin de satisfaire au mieux les propriétés attendues d'une mémoire quantique. Les travaux présentés dans ce manuscrit s'inscrivent dans ce contexte et décrivent la réalisation expérimentale d'une mémoire basée sur le protocole DLCZ dans un ensemble d'atomes froids de 87Rb. Un dispositif de double piège magnéto-optique permet de refroidir et de confiner cet ensemble au sein d'un piège dont le temps de vie est ~15 s, et de le manipuler en vue du stockage quantique. Nous disposons ainsi d'un nuage présentant une épaisseur optique à résonance de l'ordre de 5, et dont les atomes sont refroidis à une dizaine de µK. La mise en place du protocole DLCZ dans cet ensemble atomique consiste à créer des états cohérents de la matière puis à les relire, à partir de diffusions Raman qui s'accompagnent de la génération de photons uniques corrélés en impulsion. Les premiers résultats obtenus montrent des corrélations non-classiques, affichant une violation forte de l'inégalité de Cauchy-Schwarz, pour une efficacité de lecture de l'ordre de 4% et un temps de cohérence de l'état stocké de ~800 ns. Cette mémoire, utilisée comme une source de photons uniques annoncés, fait partie d'un projet pour lequel une interface basée sur de l'optique non-linéaire<br>Quantum communication aims at generating, distributing and storing qubits between distant locations, in view of implementing actual quantum networks. Coherent, efficient and reversible storage of photonic states in atomic memories is thus necessary and represents a major challenge in quantum information science. Several storage medium, such as cold atomic or solid-state ensembles, are considered so as to satisfy at best the different benchmarks of a quantum memory. In this context, the work presented in this manuscript describes the experimental realization of a memory based on the DLCZ protocol in cold atomic ensemble of 87Rb. A double magneto-optical trap system allows cooling and confining this ensemble within a trap showing a lifetime of 15 s, and to manipulate it for quantum storage. This cloud shows a resonant optical thickness of about 5, and atoms are cooled down to 10 µK. The implementation of the DLCZ protocol in this atomic ensemble consists in creating coherent states of matter and then to read them, using Raman scattering events which come along with the generation of pairs of single photons correlated in momentum. First results show non-classical correlations, which exhibit a strong violation of the Cauchy-Schwarz inequality, with a read-out efficiency of about $4\%$ and a coherence time of the stored state on the order of 800 ns. This memory, used as a heralded single photon source, is part of a project in which an interface based on non-linear guided wave optics has been built and caracterized so as to convert the 795 nm single photons generated by the memory to the telecom wavelength of 1560 nm. Both elements, combined with a entangled photon source withi
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15

Akinlotan, Morenikeji D. "Within-host dynamics of Chlamydia trachomatis infection: Repeat infections and the immune response." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/119362/1/Morenikeji%20Akinlotan%20Thesis.pdf.

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Chlamydia trachomatis is the most common bacterial sexually transmitted infection worldwide. The control of its incidence is a major public health challenge. It is one of the major preventable causes of disability and mortality. Genital Chlamydia infection is asymptomatic and thus commonly undiagnosed and untreated. In this study, we use ordinary differential equation models to provide qualitative insights into the within-host dynamics of Chlamydia infections, the associated host immune response, and the in vivo control or treatment of the infection. The thesis examines optimal control treatment strategies for acute and chronic genital chlamydial infections, including an investigation of efficacious anti-Chlamydia vaccination strategies. Qualitative results of the presented models provide frameworks for the design of new and improved treatment strategies for genital chlamydial infections.
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16

Min, Liang. "Decomposition algorithms for multi-area power system analysis." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5919.

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A power system with multiple interconnected areas needs to be operated coordinately for the purposes of the system reliability and economic operation, although each area has its own ISO under the market environment. In consolidation of different areas under a common grid coordinator, analysis of a power system becomes more computationally demanding. Furthermore, the analysis becomes more challenging because each area cannot obtain the network operating or economic data of other areas. This dissertation investigates decomposition algorithms for multi-area power system transfer capability analysis and economic dispatch analysis. All of the proposed algorithms assume that areas do not share their network operating and economic information among themselves, while they are willing to cooperate via a central coordinator for system wide analyses. The first proposed algorithm is based on power transfer distribution factors (PTDFs). A quadratic approximation, developed for the nonlinear PTDFs, is used to update tie-line power flows calculated by Repeated Power Flow (RPF). These tie-line power flows are then treated as injections in the TTC calculation of each area, as the central entity coordinates these results to determine the final system-wide TTC value. The second proposed algorithm is based on REI-type network equivalents. It uses the Continuation Power Flow (CPF) as the computational tool and, thus, the problem of voltage stability is considered in TTC studies. Each area uses REI equivalents of external areas to compute its TTC via the CPF. The choice and updating procedure for the continuation parameter employed by the CPF is implemented in a distributed but coordinated manner. The third proposed algorithm is based on inexact penalty functions. The traditional OPF is treated as the optimization problems with global variables. Quadratic penalty functions are used to relax the compatible constraints between the global variables and the local variables. The solution is proposed to be implemented by using a two-level computational architecture. All of the proposed algorithms are verified by numerical comparisons between the integrated and proposed decomposition algorithms. The proposed algorithms lead to potential gains in the computational efficiency with limited data exchanges among areas.
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17

Kunert, Kristina. "Architectures and Protocols for Performance Improvements of Real-Time Networks." Doctoral thesis, Högskolan i Halmstad, Inbyggda system (CERES), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-14082.

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When designing architectures and protocols for data traffic requiring real-time services, one of the major design goals is to guarantee that traffic deadlines can be met. However, many real-time applications also have additional requirements such as high throughput, high reliability, or energy efficiency. High-performance embedded systems communicating heterogeneous traffic with high bandwidth and strict timing requirements are in need of more efficient communication solutions, while wireless industrial applications, communicating control data, require support of reliability and guarantees of real-time predictability at the same time. To meet the requirements of high-performance embedded systems, this thesis work proposes two multi-wavelength high-speed passive optical networks. To enable reliable wireless industrial communications, a framework in­corporating carefully scheduled retransmissions is developed. All solutions are based on a single-hop star topology, predictable Medium Access Control algorithms and Earliest Deadline First scheduling, centrally controlled by a master node. Further, real-time schedulability analysis is used as admission control policy to provide delay guarantees for hard real-time traffic. For high-performance embedded systems an optical star network with an Arrayed Waveguide Grating placed in the centre is suggested. The design combines spatial wavelength re­use with fixed-tuned and tuneable transceivers in the end nodes, enabling simultaneous transmis­sion of both control and data traffic. This, in turn, permits efficient support of heterogeneous traf­fic with both hard and soft real-time constraints. By analyzing traffic dependencies in this mul­tichannel network, and adapting the real-time schedulability analysis to incorporate these traffic dependencies, a considerable increase of the possible guaranteed throughput for hard real-time traffic can be obtained. Most industrial applications require using existing standards such as IEEE 802.11 or IEEE 802.15.4 for interoperability and cost efficiency. However, these standards do not provide predict­able channel access, and thus real-time guarantees cannot be given. A framework is therefore de­veloped, combining transport layer retransmissions with real-time analysis admission control, which has been adapted to consider retransmissions. It can be placed on top of many underlying communication technologies, exemplified in our work by the two aforementioned wireless stan­dards. To enable a higher data rate than pure IEEE 802.15.4, but still maintaining its energy saving properties, two multichannel network architectures based on IEEE 802.15.4 and encompassing the framework are designed. The proposed architectures are evaluated in terms of reliability, utiliza­tion, delay, complexity, scalability and energy efficiency and it is concluded that performance is enhanced through redundancy in the time and frequency domains.
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Lin-Wen-I and 林文義. "Research of optical fiber repeater for using in DVB-T digital TV and antenna design." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/61513604117916521168.

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碩士<br>樹德科技大學<br>電腦與通訊研究所<br>94<br>In this research, we use optical fiber to transfer DVB-T standard signal. First, probe into characteristic and feasibility of transferring digital TV signal with optical fiber repeater. For this research result, when digital TV DVB-T signal enter into the optical transmitter through transferring for 10km with single mode optical fiber to optical receiver and then connecting to the optical transmitter with RF cable to receive digital TV message. Digital TV signal transferring for 10km with single-mode optical fiber, the signal had obviously decayed. We must add on prefixed magnifier in front of the optical transmitter and make it can clearly receive digital TV video to reach long-distance transmission. This thesis was divided into two parts. First part was focused on the research about optical fiber repeater which was suitable for digital TV DVB-T system (including optical transmitter and optical receiver) and relevant criterion testing.
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Chuan-Shu and 陳卷書. "Optimal Predictors on Repeat Prostate Biopsy : A Retrospective Analysis." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/42154860189296333359.

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碩士<br>中山醫學大學<br>醫學研究所<br>98<br>Purpose: The aim of our study was to identify the optimal predictor of prostate cancer among several prostate-specific antigen (PSA) derivatives in repeat prostate biopsy. Methods: We retrospectively assessed the repeat prostate biopsy specimens, obtained between 1999 and 2008, of 212 patients with total PSA (tPSA) of 4-10 ng/ml and normal digital rectal examination (DRE). Using receiver operating characteristic (ROC) analysis, we assessed the predictive power of tPSA, percent free PSA (f/t PSA), PSA density (PSAD), and PSA velocity (PSAV) for detection of prostate cancer. Results: Repeat prostate biopsy specimens were positive for prostate cancer in the case of 26 patients and negative in the case of 186 patients. The areas under the ROC curve for tPSA, f/tPSA, PSAD, and PSAV were 72.7%, 57.9%, 74.4%, and 64.8%, respectively. The ROC curve analysis revealed that PSAD was a better predictor of prostate cancer than f/t PSA. Moreover, when PSAD at an optimal cutoff of 0.18 ng/ml/cc was considered as the predictor, the detection of prostate cancer was found to have a high sensitivity and specificity ( 77% and 69%, respectively). Conclusions: In repeat prostate biopsy, PSAD is superior to f/t PSA as a predictor of prostate cancer and by assessing this predictor, unnecessary repeat biopsy of patients with tPSA of 4-10 ng/ml can be avoided.
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Lee, Yuan-Hsuan. "Longitudinal Data Analysis Using Multilevel Linear Modeling (MLM): Fitting an Optimal Variance-Covariance Structure." Thesis, 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8464.

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This dissertation focuses on issues related to fitting an optimal variance-covariance structure in multilevel linear modeling framework with two Monte Carlo simulation studies. In the first study, the author evaluated the performance of common fit statistics such as Likelihood Ratio Test (LRT), Akaike Information Criterion (AIC), and Bayesian Information Criterion (BIC) and a new proposed method, standardized root mean square residual (SRMR), for selecting the correct within-subject covariance structure. Results from the simulated data suggested SRMR had the best performance in selecting the optimal covariance structure. A pharmaceutical example was also used to evaluate the performance of these fit statistics empirically. The LRT failed to decide which is a better model because LRT can only be used for nested models. SRMR, on the other hand, had congruent result as AIC and BIC and chose ARMA(1,1) as the optimal variance-covariance structure. In the second study, the author adopted a first-order autoregressive structure as the true within-subject V-C structure with variability in the intercept and slope (estimating [tau]00 and [tau]11 only) and investigated the consequence of misspecifying different levels/types of the V-C matrices simultaneously on the estimation and test of significance for the growth/fixed-effect and random-effect parameters, considering the size of the autoregressive parameter, magnitude of the fixed effect parameters, number of cases, and number of waves. The result of the simulation study showed that the commonly-used identity within-subject structure with unstructured between-subject matrix performed equally well as the true model in the evaluation of the criterion variables. On the other hand, other misspecified conditions, such as Under G & Over R conditions and Generally misspecified G & R conditions had biased standard error estimates for the fixed effect and lead to inflated Type I error rate or lowered statistical power. The two studies bridged the gap between the theory and practical application in the current literature. More research can be done to test the effectiveness of proposed SRMR in searching for the optimal V-C structure under different conditions and evaluate the impact of different types/levels of misspecification with various specifications of the within- and between- level V-C structures simultaneously.
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21

Decrouppe, Andre. "Optimal Incentives to Foster Cross Selling: An Economic Analysis." Thesis, 2014. http://epub.wu.ac.at/4486/1/Dissertation_Andre_Decrouppe_Learn@WU.pdf.

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Cross selling is the practice of selling additional products to an existing customer. It has the potential to boost revenues and can be beneficial for both the company and the customer. For many multi-divisional companies with product or service oriented organizational structures the attempt to realize the benefits of cross selling generates incentive problems. In this thesis, three problems spread over three business levels are identified. Firstly, management needs to (financially) motivate business units in fostering their cross selling efforts. Secondly, in order to make cross selling happen, business units need to cooperate and to exchange product-related information. Finally, in order to increase their short-term benefits business units might act opportunistically by selling products or services of other business units without paying attention to adding value for their customers. These incentive problems are theoretically examined by applying principal-agent theory and the theory of repeated games. Our findings suggest that an optimized incentive structure is required to make both the business units and the management better off. The thesis also analyses the circumstances and necessary prerequisites under which cross selling initiatives are beneficial for all involved parties. Apart from that cross selling sometimes may turn out to be non-beneficial. In addition to the elaborations above, risks and hazards of cross selling are presented in detail and applied for the extension of the underlying model. Bottom line, the work underlines that cross selling is to be realized holistically to ensure durable success. (author's abstract)
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22

Chen, Yu-Hong, and 陳昱宏. "Optimal Energy Allocation for Polar Codes with Hybrid Automatic Repeat Request." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/rwkxbw.

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碩士<br>國立臺灣科技大學<br>電子工程系<br>107<br>With the advancement and convenience of technology, digital transmission has become an indispensable part of human life. Among them, polar code is the most popular one and ready to be applied to the fifth generation mobile communication (5G) coding. Because the transmission process is often influenced by various interferences, noise, and other factors, receiving an erroneous packet could lead the transmission failure. Therefore, in addition to continuously enhancing the coding technology to reduce the error rate, the retransmission mechanism in case of transmission error has become an important part. There are two major types of retransmission mechanisms for polar codes, namely, the Chase Combined Hybrid Automatic Repeat reQuest (CC-HARQ) and Incremental Redundancy Hybrid Automatic Repeat reQuest (IR-HARQ). The former scheme operates in a conventional manner. That is, after receiving the retransmission command, the same packet is retransmitted, and then the observation result is integrated and decoded at the receiver. The latter scheme retransmits part of the extended code word. After the packet is retransmitted, the two observations are merged into the extended polar code, and then decoded. Retransmission will greatly reduce the error rate. Considering the conditions of code length, code rate, and channel environment, this work proposes energy allocation among transmission and retransmission. The goal is to minimizing an indicator that consider the expected energy consumption and the expected throughput. However, in order to do the consumption for the energy allocation, it is necessary to do a lot of simulations to obtain various error rates. This is extremely time-consuming. Therefore, we use Gaussian approximation to quickly estimate the value of reference under different conditions. The error rate thus obtained is then used to achieve a fast optimization for energy allocation.
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Wen-Hsien, Chiu. "Optimal Rate-Diversity Tradeoff Space-Time Codes Based on Irregular Repeat-Accumulate Codes." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-1907200611285300.

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Chiu, Wen-Hsien, and 邱文賢. "Optimal Rate-Diversity Tradeoff Space-Time Codes Based on Irregular Repeat-Accumulate Codes." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/61063304437907609553.

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碩士<br>國立臺灣大學<br>電信工程學研究所<br>94<br>The design of smart-greedy space-time (ST) codes for multiple-input multiple-output (MIMO) wireless systems in a variety of mobility conditions is an open problem of great interest. Motivated by the algebraic space-time constructions of Lu and Kumar, which achieve the transmit diversity gain and permit the maximum transmission rate possible, we propose an algebraic method for constructing optimal ST codes in the sense of achieving the rate-diversity tradeoff. We also show that our codes belong to a class of irregular repeat-accumulate codes which can provide the potential of seizing possible temporal diversity. In this thesis, we first present new space-time codes using maximal rank-distance accumulate (MRDA) codes whose encoder consists of a repeater, an edge interleaver, a single parity-check encoder, and a simple accumulator. Based upon their factor graph representations, we employ efficient massage-passing algorithms on the combined graph of a turbo MIMO receiver composed of an inner MIMO detector and an outer MRDA decoder. We show that for rate-1 MRDA codes, the well-known sum-product algorithm suffices. However, it does not work for high rate MRDA codes. The convergence problems are solved by introducing the modification of the code structure and the adaptive sum-product algorithm. From the simulation results, more temporal diversity can be obtained in fast fading channels as the block size increases. The main difficulty in increasing the block size of MRDA codes is that the block size T is the degree of primitive polynomial such that designing codes of large T needs inevitable exhaustive search. Without a exhaustive search for primitive polynomial with large degree, a large size scheme called cascade-interleave maximal rank-distance accumulate (CIMRDA) codes is proposed. Furthermore, based on the binary (CI)MRDA codes, a generalized unified construction which yields ST codes over commonly used constellations such as PAM, QAM, 2k-PSK is discussed.
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"A comparison of flexibility training and the repeated bout effect as priming interventions prior to eccentric training of the knee flexors." Thesis, 2015. http://hdl.handle.net/10388/ETD-2016-06-2283.

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Performance of a series of eccentric contractions produces adverse effects including muscle weakness, delayed onset muscle soreness (DOMS), fluid accumulation and decreased muscle function. The repeated bout effect is a physiological adaptation observed when a single-bout of eccentric exercise protects against muscle damage from subsequent eccentric bouts. Similar to the repeated bout effect, increases in flexibility have been linked to attenuations in acute muscle damage, muscle fatigue and strength loss after eccentric exercise. Purpose: The purpose of this study was to examine the muscle physiological responses to eccentric strength training after first priming the muscles with either a period of static flexibility training or a single intense bout of eccentric exercise performed weeks earlier; and compare these to the responses from eccentric strength training when no prior intervention is administered. Methods: Twenty-five participants were randomly assigned to a flexibility (F) (n=8), a single-bout (SB) (n=9), or a control (C) (n=8) group. The design consisted of two 4-week phases; 1) priming intervention, 2) eccentric training. The priming intervention included static stretching (3x/week; 30mins/day) (F), a single-bout of eccentric exercise (SB) or no priming intervention (C). All groups proceeded to complete eccentric training of the knee flexors using isotonic contractions (%load progressively increased over training period) on a dynamometer following the priming intervention phase. Testing was completed at baseline, post-priming intervention and post-eccentric training, in conjunction with data being collected during the acute eccentric training phase (0hr, 24hr, 48hr; post-bout 1 and 4). Dependent measures included muscle thickness, isometric maximal voluntary contraction (MVC), eccentric and concentric MVC, optimal angle, active range of motion (ROM), passive ROM, maximal power, electromyography (EMG) and delayed onset muscle soreness (DOMS). Results: Acute data during the eccentric training phase revealed a significant reduction in DOMS for both the F and SB groups compared to the C following the first bout of eccentric exercise (p<0.05). The F also had reduced soreness in comparison to both the SB and C post fourth bout of eccentric exercise (p<0.05). The F group demonstrated attenuated loss in isometric strength (post fourth bout) and maximal power (post first bout) during eccentric training compared to the C group (p<0.05). However, there was no significant difference between groups across all dependent variables following the eccentric training phase. Conclusion: This is the first study to directly compare the protective effects observed with static flexibility training to that of a single-bout of eccentric exercise throughout a subsequent eccentric training regime. Although differences in muscle soreness, strength and maximal power occurred during the acute stages of eccentric training, there appeared to be no significant advantage of either protective priming method at the end of eccentric training.
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