M. Tech. (Department of Process Control and Computer Systems, Faculty of Engineering and Technology), Vaal University of Technology. / The telecommunication and utility cable monitoring system was implemented to protect the cable tampering. Cable tampering occurs despite the fact that methods have been developed, to solve and decrease cable tampering cases such as cable tampering prevention campaigns at the national and international level, organizing security patrols, replacing existing cable with fiber cables and I-Watch system installation. The objective of the research was to design and implement a cable tampering monitoring system which is able to monitor, detect, pinpoint the location and give the distance from the sensor at which the cable tampering took place. The system is an improvement on the traditional cable anti-theft monitoring system, the method of tracking resonance signal frequency was implemented. The system incorporates a sensing circuit which detects a change on the capacitance value of the cable and converts it into an equivalent frequency value, Field-Programable Gate Array (FPGA) board is utilized to convert the frequency into the cable length (the distance from sensor of cable which was taken away), after detecting an anomaly on the cable (tampered with) the output of the system is divided into two parts which are display mode and messaging mode. For display mode, the system uses a Liquid Crystal Display (LCD) which displays the GPS Coordinates of the location where the cable tampering took place and the distance from sensor of the cable which has been tampered with. In the messaging mode, the FPGA activates the GSM module and the module sends alert flag message to the user when the cable is tampered with.

Les robots parallèles à câbles sont une variante originale des robots parallèles. L'utilisation de câbles en lieu et place des segments rigides procure à ce type de robots un espace de travail potentiellement très grand car des longueurs importantes de câbles peuvent être déroulées. Toutefois, dans la plupart des études sur les robots à câbles, un modèle de câble sans masse non élastique est utilisé. Si dans le cas de robots de faibles dimensions soumis à de faibles efforts, ce modèle est valide, lorsque l'on considère des applications de très grande dimension pour lesquels la masse des câbles et l'élasticité ne peuvent plus être négligées, ces modèles simples ne sont plus valables. Ces travaux de thèse proposent des nouvelles méthodes d'étude des robots parallèles à câbles de grande dimension. Dans un premier temps, des tests de traction réalisés sur différents câbles permettent de proposer différents modèles élastiques. La modélisation d'un câble par une caténaire élastique est ensuite rappelée, et l'erreur importante obtenue en négligeant la masse des câbles est mise en exergue. La modélisation par caténaire élastique bien que précise, nécessite la résolution d'un système d'équations couplées non-linéaires. Un modèle simplifié de câble pesant est alors présenté. Il permet, sous l'hypothèse de faible déflection du câble, de simplifier la résolution de l'équilibre statique d'un robot à câble. Ce modèle permet également de développer des outils utiles à la détermination de l'ensemble des torseurs d'efforts admissibles à la plate-forme d'un robot parallèle à câbles. La vérification de l'inclusion de l'ensemble des torseurs nécessaires à la réalisation d'une tâche dans l'ensemble des torseurs admissibles est finalement utilisée comme critère d'optimisation pour une méthode de conception de robots à câbles de grandes dimensions. / Cable-driven robot is an original variation of parallel robots. Replacing rigid bodies by cables provides new capabilities to these robots, and particularly large-size workspaces, since long cable lengths can be deployed. In the literature, cables are usually supposed to be inextensible and massless. If this modeling is valid for small robots with moderate payloads, this cable model is not accurate enough to be used for large dimension cable-driven robots. The work presented here focuses on the modeling of such large cable robots. First, from a set of traction tests applied to various cables, elastic models are proposed. Then, the well-know elastic catenary model is recalled, and its effects on the modeling of large dimension cable robots is shown. However, when using this cable model, solving the platform static equilibrium require the resolution of a non-linear coupled equation system. Assuming a low sagging of the cable, some simplifications can be made to this model. The resulting simplified hefty cable model is then presented and the new expression of the static equilibrium is shown to be close to the one obtained with the massless cable model. Thus, it allows us to determine the set of admissible mobile platform wrenches at a given pose. By comparing this set to the set of required wrenches for a specific task a cost function is finally defined and used in a design procedure dedicated to large dimension cable-driven robots.

Orientadores: Alberto Luiz Francato, Carlos Alberto Mariotoni / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-18T13:32:01Z (GMT). No. of bitstreams: 1 Barbosa_CarlosDavidFranco_D.pdf: 7182306 bytes, checksum: 6a8fd84aba169e2fceffb93e27a4c5b5 (MD5) Previous issue date: 2011 / Resumo: Esta tese tem como objetivo estudar métodos de planejamento da expansão da transmissão de energia elétrica em mercados de eletricidade re-estruturados, tanto em um ambiente tradicional quanto com a adoção de inovações tecnológicas. No trabalho são estudados procedimentos de campo para as linhas de transmissão, considerando economia e confiabilidade, principalmente em emendas a compressão para cabos ACSR (Aluminum Core Steel Reinforced). O trabalho descreve os resultados de pesquisas efetuadas com fabricantes e concessionárias usuárias das emendas a compressão e ainda sugere alguns procedimentos e rotinas de inspeções para melhorar a confiabilidade do sistema. Os resultados dos testes com as emendas, realizados em laboratório, serviram para dar suporte para a analise de falhas, subsidiando a avaliação das causas de falhas mais frequentes no ambiente competitivo. Por fim foram apresentadas tecnologias emergentes com possibilidade de redução da taxa de falhas nos sistemas de transmissão de energia elétrica bem como as recomendações de boas praticas para o setor / Abstract: This thesis has as objective to study electricity transmission expansion planning In re-structured markets, both traditional as well as with technological innovations. In the work are studied transmission lines field procedures considering economy and reliability, mainly ACSR (Aluminum Core Steel Reinforced) compression splices. The work describes compression splices field surveys with suppliers and users concessionaries and also suggest some procedures and inspections routines to improve system reliability. The results of laboratory splice tests helped the failure analysis and frequently failure causes on competitive environment. Finally it is presented emerging technologies with failure reduction possibilities for the electricity transmission systems and good practices recommendations for sector / Doutorado / Recursos Hidricos, Energeticos e Ambientais / Doutor em Engenharia Civil

Diploma thesis focuses on a problematics of an optical networks in terms of an optical cables laying and a work with individual fibers. Thesis contains an basic physical properties which are used in a fiber optics. Methodology of correct working procedures used in fiber optics is discussed at the same time. Thesis also contains detailed documentation of realized optical connections including scheme of realized outdoor connection. 3D design of an rack case is also part of the thesis. Rack case provides an option to simulate plenty of different lengths of optical routes. Rack case is designed in 6U variant.

This master’s thesis is concerned with analysis of cabling and cabling systems in data center and with their projection as follows. The part of the work is aimed at the measurement parameters of metal cables which are used in data center with noise. The first part is focused on analyzing the structure of the data center and cabling used in it. The structure of the data center is based on the TIA-942 and consists of an entrance room, main distribution area MDA, horizontal distribution area HDA , zone distribution area ZDA and the equipment distribution area EDA. Divided into backbone cabling and horizontal cabling and use standard and pre-terminated cabling. The measurement results of structured metal cabling with noise are discussed in the next part. There were used these types of cables UTP, FTP and S/FTP. The measurement was performed in the electricity substation and in the laboratory of electromagnetic compatibility. The third part of this work deals with the actual design of structured cabling for the data center. In the first design we use the standard installation, the second preterminated cabling. For both types of installation cost statement is processed (CAPEX). Thesis is also completed with DC design drawings and rack drawings.

My work focuses on taking waste wire-grade PVC = poly(vinyl chloride) and waste XLPE = cross-linked polyethylene and recycle them into small wire/cable spool technology in order to reduce waste cost and reduce cost of spool production. The PVC and XLPE were provided by Encore Wire Corp. of McKinney, TX; they have also defined the standard to which I am comparing my results. The end goal is to incorporate as much PVC and XLPE into the spools while maintaining material toughness, impact resistance, as well as cost-effectiveness in the implementation of the waste materials. The work has been divided into two primary sections, the first is focused on improving material strength through the addition of ceramic fillers. The second section is focused on adding PVC and XLPE into a stronger and highly cohesive polymer matrix and optimizing the concentration of the waste products. Since XLPE is non-polar while PVC is strongly polar, compatibilizers such as CPE (chlorinated polyethylene) and MA-DCP (maleic anhydride with dicumyl peroxide) were used to improve interactions between polar and non-polar constituents. Testing involved the tensile mechanical properties, tribology and thermal properties, namely dynamic mechanical analysis (DMA) and evaluation of thermal degradation by thermogravimetric analysis (TGA). Combining PVC and XLPE together is not economically feasible with current compatiblizers. At the same time, introduction of PVC waste or XLPE waste with sufficient properties of the resulting composites is doable.

Modelling objects and simulating them do not always map to each other, and often requires defining additional information outside the scope of the original model to achieve an accurate simulation. For example: cables in \textit{AGX Dynamics} (a simulation library from Algoryx AB) are entirely defined by its physical parameters (e.g. Young's modulus, stiffness, etc.), radius, and the route through which the cables run. This thesis explores two approaches to closing the gap between the modelling of a cable and the creation of one in AGX Dynamics through evaluating current methods applied to generating a route and radius from a mesh. Two methods are identified as being useful in generating a route for a cable from a mesh: one which is a surface simplification algorithm, creating approximations of models using non-manifold meshes with radii defined at each vertex, and another method which creates a skeleton from a model using the surface's curvature to gradually shrink the model into a zero-volume shape. Both methods are evaluated using two different approaches to measuring the closeness to the original mesh from the results: using the metric introduced in the surface simplification method applied along the route, and measuring the mean distance from each point on the surface to the route. We show a clear advantage in the first method's inherent way of approximating the radius of the model but also its lack of detail. We also demonstrate that the second method produces more detailed skeletons, but in turn has issues with skewed routes which do not follow the original mesh. Both methods have their own advantages and disadvantages and with improvements to both radius calculations or adaptions to the fundamental algorithms, they could provide a great way of creating AGX cables from mesh models.

This thesis presents a method for optimizing cable configuration inside a large magnetic cylindrical steel casing, from the total ampacity point of view. The method is comprised of two main parts, namely: 1) analytically calculating the electromagnetic losses in the steel casing and sheathed cables, for an arbitrary cables configuration, and 2) implementing an algorithm for determining the optimal cables configuration to obtain the best total ampacity. The first part involves approximating the eddy current and hysteresis losses in the casing and cables. The calculation is based on the theory of images, which this thesis expands to apply to casings having both high magnetic permeability and high electric conductivity at the same time. The method of images, in combination with approximating the cable conductors and sheaths as multiple physical filaments, is used to compute the final current distributions in the cables and pipe and thus the associated losses. The accuracy of this computation is assessed against numerical solutions obtained using the Maxwell finite element program by Ansoft. Next, the optimal cable configuration is determined by applying a proposed two-level optimization algorithm. At the outer level, a combinatorial optimization based on a genetic algorithm explores the different possible configurations. The performance of every configuration is evaluated according to its total ampacity, which is calculated using a convex optimization algorithm. The convex optimization algorithm, which forms the inner level of the overall optimization procedure, is based on the barrier method. This proposed optimization procedure is tested for a duct bank installation containing twelve cables and fifteen ducts, comprising two circuits and two cables per phase, and compared with a brute force method of considering all possible configurations. The optimization process is also applied to an installation consisting of a single circuit inside a large magnetic steel casing.

This thesis presents a method to obtain the per-unit-length electrical parameters of a given overhead transmission line or underground cable in an unbounded space considering the effect of the ground. This is achieved using a two-dimensional conformal mapping technique, which consists of a modified bilinear transformation to map a semi-open half-space problem into a unit circle. The Helmholtz equations describing the quasi-stationary approximation for the electromagnetic field behaviour are solved using finite element method, with the aid of commonly used commercial software program, COMSOL Multiphysics. The per-unit-length resistance, inductance and capacitance are calculated using the proposed mapping method, the truncation of the original space method and then compared with the analytical solution obtained from Carson's approximation for the overhead lines and Wedepohl's formulation for the underground cables. / October 2016

This thesis introduces a comprehensive methodology to improve electromagnetic transient (EMT) modelling of power cables systems. Several improved modelling and validation techniques are proposed at the parameter estimation, time domain simulation and validation stages of the EMT modelling of transmission lines. A novel approach is developed to model sector-shaped cables in electromagnetic transient type programs. First, the applicability of elemental sub-conductor technique is extended to accurately calculate the frequency dependent impedances of sector-shaped cables. The derived admittance and propagation characteristics of the sector-shaped cable are fitted with rational functions using the method of vector fitting in an EMT-type program. The time domain simulations are validated with the numerical inverse Laplace transform method. A novel frequency domain approach is presented to model cascaded transmission systems. The procedure is based on obtaining four composite propagation functions representing the cascaded system. The performance of the technique does not diminish with increased number of cascaded segments and it preserves the intrinsic details of each line segment. This method is capable of modelling cascaded overhead lines or cables with different characteristic admittances and line lengths. This method can be used to validate EMT models of cascaded transmission systems. An improved generalized transmission line model is introduced which is capable of accommodating time steps greater than the travel time of the line. The time step of the conventional EMT models of transmission lines is constrained by the smallest travel time of the line. When the high frequency transients at the line terminations are not of interest, inaccurate nominal π equivalents are used with large time steps to reduce the computational burden. The proposed model not only is more accurate than the π equivalents, but also degenerates to the conventional frequency dependent EMT model when used with time steps smaller than the travel time. Therefore, the proposed model is highly convenient as it can be used for all types of EMT simulations without resorting to nominal π equivalents when the large simulation time steps must be used to reduce computational burden. / February 2017