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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Protection of cross-bonded cable systems using non-linear inductive device

Ghani, M. M. Abdul January 1991 (has links)
No description available.
2

Implementation of Ethernet in broadband cable networks

Poon, F. S. January 1987 (has links)
No description available.
3

Structured cabling

Sanchez Martin, Jesus Alberto 01 October 2012 (has links)
This thesis discusses the design and implementation of a structured cabling system. A structured cabling is the way of standardizing the communications like telephony and ISDN in the buildings and facilitate the future scalability. In our case, we study the structured cabling system for a certain University building (in cooperation with Technical Services of University of Patras (Planning & Networks Directorate), University of Patras). The study of structured cabling is based in the necessities of the building. Depends of the building and its purpose the necessities are different. For a University building the structured cabling is design as a work place, so the study will be focus on a professional sphere, based in some defined standards. We need to define the exactly components that will be part of the system and their localization in the building, as well as their cost and installation. For this purpose we use AutoCAD in order to help us to define the needed components and their localization, with the help of some plans of the building. / -
4

Ανάπτυξη διαδραστικού συστήματος τεκμηρίωσης και διαχείρισης της δομημένης καλωδίωσης / Development of an interactive application for the documentation & management of a structured cabling system

Γεωργίου, Παναγιώτης Βασίλης 05 February 2015 (has links)
Η διπλωματική αυτή εργασία εκπονήθηκε με σκοπό την δημιουργία ενός προγράμματος για τη διαχείριση του δικτύου Δομημένης Καλωδίωσης. Μέσω της εφαρμογής αυτής, δίνεται η δυνατότητα στον χρήστη να έχει μία πλήρη εικόνα της εγκατεστημένης δομημένης καλωδίωσης του κτηρίου και να μπορεί να παρέμβει άμεσα και αποτελεσματικά σε κάθε περίπτωση τροποποίησης ή δυσλειτουργίας. Το πρόγραμμα υλοποιήθηκε στη γλώσσα προγραμματισμού AutoLISP, που λειτουργεί μέσα από την πλατφόρμα του σχεδιαστικού προγράμματος AutoCAD. Χρησιμοποιήθηκαν τα σχέδια των ορόφων του κτηρίου των Ηλεκτρολόγων Μηχανικών του Πανεπιστημίου Πατρών, όπου, στα πλαίσια της επίτευξης του στόχου, σχεδιάστηκε το σύστημα δομημένης καλωδίωσης. Στην εργασία αυτή, παρουσιάζονται τα βασικά στοιχεία ενός συστήματος δομημένης καλωδίωσης, καθώς και τα εργαλεία υλοποίησης του προγράμματος όπως το σχεδιαστικό πρόγραμμα AutoCAD, η γλώσσα προγραμματισμού AutoLISP, και η γλώσσα σήμανσης Dialog Control Language (DCL). Αρχικά, παρουσιάζεται η διαδικασία σχεδίασης του συστήματος δομημένης καλωδίωσης στο AutoCAD. Μετέπειτα, δίδεται μια περιγραφή του προγράμματος και των λειτουργιών του, και ο πηγαίος κώδικας που αναπτύχθηκε, σε συνδυασμό με λογικά διαγράμματα για την καλύτερη κατανόηση του. Στο παράρτημα, αναλύονται τα υποπρογράμματα που σχεδιάστηκαν για να προσφέρουν επιπλέον δυνατότητες, και το εγχειρίδιο χρήσης της εφαρμογής. / The aim of this thesis is to create an application software for the management of a Structured Cabling System (SCS). Through this application, the user is able to have a complete picture of the installed structured cabling network of the building and be able to intervene quickly and effectively in any case of modification or malfunction. The program was implemented using the programming language AutoLISP, which operates through the CAD software platform of AutoCAD. The architectural floor plans used were those of the building of Electrical Engineering Department, at the University of Patras, where, in the context of achieving the target, the structured cabling system was designed. This thesis presents the basic elements of a structured cabling system, and the tools for implementing the program, i.e. the CAD program AutoCAD, the programming language AutoLISP, and the markup language Dialog Control Language (DCL). The design process of the structured cabling system in AutoCAD is presented initially. Thereafter, a description of the program and its features are presented, as well as the source code that was developed, in conjunction with logic diagrams for clarity. In the Annexes, the subroutines designed to offer additional features are analyzed and the manual of the application is included.
5

Legendrian and transverse knots and their invariants

Tosun, Bulent 14 August 2012 (has links)
In this thesis, we study Legendrian and transverse isotopy problem for cabled knot types. We give two structural theorems to describe when the (r,s)- cable of a Legendrian simple knot type K is also Legendrian simple. We then study the same problem for cables of the positive trefoil knot. We give a complete classification of Legendrian and transverse cables of the positive trefoil. Our results exhibit many new phenomena in the structural understanding of Legendrian and transverse knots. we then extend these results to the other positive torus knots. The key ingredient in these results is to find necessary and sufficient conditions on maximally thickened contact neighborhoods of the positive torus knots in three sphere.
6

High frequency performance of structured wire cabling in communication systems

Al-Asadi, Mohammed Mahdi Mohammed January 2000 (has links)
Twisted pan (structured wire) cabling is a principal component in the communications infrastructure, with millions of meters being installed weekly. The rate of increase in upper frequency for this cable appears to be doubling approximately every two years. Clearly, a rigorous approach to the design of these cables is fundamental to achieving data transmission at these frequencies with increasingly stringent performance requirements. This thesis derives a family of equations for the secondary parameters based on an explicit relationship between cable dimensions and materials. These equations have been validated against experimental results and fOWld accurate. Further. equations are developed which calculate the overall S-parameters for cascaded multi.pair cables, the return loss and cross-talk between transmission charmels. In tenns of cable specification. the secondary parameters are the most significant with many of the perfonnance criteria based on these. With designs based largely on the manipulation of physical dimensions, there has been no family of secondary parameter equations given explicitly as functions of cable dimensions and material properties. Similarly, tools have not existed to allow the investigation of design variability or the effects of handling and installation. These are principal requirements in the cable design process. A modelling package, based on Transmission-Line Matrix (TLM) modelling, is developed to a1low the investigation of manufacturing variability and installation handling effects on overall perfonnance of a cable. This modelling technique is validated against both experimental results and analytical results the comparison is excellent. Finally a novel method for the calculation of cross talk between cable pairs is presented. This method is based on a hybrid field·circuit model. Comparisons with measurements show good agreement.
7

A novel phonon-scintillation cryogenic detector and cabling solution for dark matter direct detection

Zhang, Xiaohe January 2015 (has links)
The EDELWEISS experiment is one of the dark matter direct detection experiments. It aims to detect WIMP interactions using an array of cryogenic germanium detectors. In the previous EDELWEISS-II phase, the cables and connectors used have been identified as a major source of neutron background in the experiment, which means that further effort aimed at better WIMP-nucleon interaction detection sensitivity requires a new, different cold cabling solution connecting the detectors to the front-end electronics. Motivated by this, a new two-section cold cabling system based on semi-flexible laminated copper and stainless steel cables has been developed for the EDELWEISS- III phase at Oxford. Batches of prototypes have been tested first in a cryostat at Oxford as part of a phonon-scintillation detector module, and then at the LSM underground laboratory in several EDELWEISS-III commissioning runs. Following that, a final set of cabling has been produced and installed in the EDELWEISS-III setup, which is currently conducting a science run aiming to improve its sensitivity reach compared to the previous results. This new cold cabling system has shown similar electrical performance as the previous coaxial cabling when comparing different cold cabling configurations in a commissioning run at LSM. Also, its background contribution is within the EDELWEISS-III requirements, according to radioactivity level tests and Monte Carlo simulations. In addition, the assembled connectors have allowed hundreds of signal tracks to be installed within a few days and the low material and space budget has made the cables compatible with the compact cryostat design. Besides reading out detectors for dark matter detection, prototypes of this cabling solution for a wider application range have also been produced at Oxford. The next generation dark matter direct detection experiments aim to achieve detection sensitivity better by a few orders of magnitude. This requires a target mass at tonne-scale, which converts to thousands of cryogenic detectors. Cryogenic phonon-scintillation detectors used in current dark matter searches can provide excellent performance but they usually require individual tuning and attention, making operation in large-scale experiments difficult. It is also technically challenging to stably produce such detectors in large quantity. Therefore, a scalable, robust novel detector concept for cryogenic phonon- scintillation detectors to be used in future rare event search experiments has been developed in this work. This detector module consists of a phonon detector based on a CaMoO4 scintillating crystal as the target with an attached NTD-Ge sensor as the thermometer, and a light detector based on a low-temperature PMT. To provide the high voltage necessary for PMT operation while ensuring the detector module can be cooled down and that the performance of the phonon detector is unaffected, a high voltage supply system based on a Cockcroft-Walton generator (CWG), a transformer and a small AC input has been designed and tested in the cryostat. The laminated cabling system is chosen for reading out the phonon channel and connecting the CWG and the PMT. A test run has demonstrated that, the high voltage can be provided to the PMT without causing a problem to the detector operation, and it is feasible to operate the low-temperature PMT at a temperature as low as 17 mK. Testing with a cobalt-57 gamma source, the phonon detector and the light detector have achieved resolutions of 1.07 keV and 34.2 keV for the 122.06 keV peak respectively. This is close to the performance of detectors used in the current dark matter direct searches, proving this detector concept can be applied to future large-scale dark matter direct detection experiments and other rare event searches. Using the light channel in this detector setup, the scintillation properties of CaMoO4 has been studied. In this work, the experimental data of its scintillation decay time constant has been extended from the previous 7 K to milli-Kelvin temperatures. The data are interpreted using a three-level model, confirming the existence of a metastable emission level in CaMoO4, and giving various parameters of its emission centre. This suggests that the work related to producing a high voltage supply and demonstrating the excellent performance of a low-temperature PMT could also be attractive to scintillator studies at cryogenic temperatures.
8

High frequency Ethernet cabling analysis and optimization

Ogundapo, Olusegun January 2016 (has links)
This thesis provides analytical and forensic tools for data cabling, with particular focus on Ethernet cabling to assist designers and those involved in deployments in analyzing cable performance and the reasons behind the actual performance obtained. The need for higher bandwidth to accommodate increasing demand for multimedia services and data centers network infrastructure led to the formation of IEEE P802.3bq to create standards for 40GBASE-T over twisted pair cables. The 40GBASE-T is expected to offer bandwidth of up to 2000MHz over a maximum channel length of 30m. The research investigated means of predicting key performance parameters in Ethernet cabling standardization using the 40GBASE-T as an example. The performance parameters prediction method provided is equally applicable to ongoing and future high data rate Ethernet cabling standardization such as the 2.5/5GBASE-T and 50/100GBASE-T. Another problem in the Ethernet networking world is the availability of counterfeit and non-standards compliant twisted pair cables in the market. The significant amount of communications cables in the market containing copper clad aluminum cable or other non-standards compliant conductors disguised as Category 6 cables can pose serious problems to companies’ networks, the contractors or the installers. This is in view of the growing demand for internet of things (IOT) services that makes it imperative to have a reliable Ethernet driven communication network to support the required infrastructure. This thesis therefore, provides techniques that can be used to evaluate cables key performance parameters using the Feature Selective Validation method and the Kolmogorov-Smirnov (KS) test. The technique can help engineers avoid subjective judgement and make objective decisions in the selection of cables. The research provided a technique that can be used to reverse engineer impedance profile from the return loss measurement of Ethernet cables using genetic algorithms. The method can be applied in situations where time domain tests are inaccessible or only simple (magnitude) tests in the frequency domain are available and there is the need for impedance profiles of cables to evaluate their performance or physical integrity before or after installation. The method can also be useful where only simple (magnitude) tests are the only historical data available for the cables and facilities for time domain reflectometry measurements are inaccessible. This research also presented a method of evaluating and predicting NEXT in unshielded twisted pair (UTP) using Category 6 cables as an example. The results obtained from the evaluation were used to provide crosstalk parameters for fast NEXT prediction in Category 6 (UTP) cables. The research used the measured NEXT of three Category 6 (UTP) cables from different manufacturers for evaluation and validation. The evaluation and modeling method can thus be useful to engineers investigating NEXT in the design of data communication systems.
9

Návrh realizace počítačové sítě pro střední školu / High School Computer Network Realization Design

Kožiak, Ján January 2018 (has links)
The aim of this thesis is to create a computer network for Secondary Professional School in Tisovec. In the theoretical part we explain the terms connected to our issue. The practical part focuses on the creation of a computer network. This part includes a selection of suitable network components, graphical display of network wiring and data connector arrangement. The thesis deal with the project creation, thus in the practical part we describe computer network from a project management point of view.
10

Výzkum vhodnosti různých aplikací multimediální kabeláže / Research into the appropriateness of diverse multimedia cabling applications

Tichý, Ondřej January 2008 (has links)
The reader can find a summary of metallic structured cabling in this thesis. It means there is described progress of this cabling and the specifications of the cabling systems. There are also described all types of these cables and some of connectors. The types of cable are summed in the table at the end of this part. In another part there are shown some aplications used for structured cabling. In the futher part there are described tests defined in the specifications in more detail. The most importatnt part of this thesis is focused on various tests. Firstly, there were chosen typical representative of the cables. It was: the data cable (Category 6), S/STP and MediaTwist cable. These cables were underwent the standard tests described above and theirs results are appended on the attached CD. In the last part of this thesis there are intrinsic tests of fitness cables to the multimedia signal. Of course, the tests were chosen to measure cable to obtain the most suitable type of cable. However, these tests were not standard measurement. There were simulated occasions from the practise. The goals of this thesis were to achieve the results, to compare them between each other and to make a decision, which cable is the most suitable for the multimedia signal. Definitely, this thesis should be sufficient at least for people who keep track of structured cabling. Eventually, the clear decision was made from these testings. MediaTwist cable is the most suitable type for the multimedia signal, because the signal is being recognized correctly in almost every case even if the long length. The result from the testings in more detail can be found at the very end of this thesis. So, if you are interested, please, continue in reading.

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