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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

Faraday current sensing using chromatic modulation

Li, Gongde January 1997 (has links)
No description available.
2

Análise de soluções tecnológicas para comunicações Power Line Carrier (PLC)

Soares, Pedro Hugo Anselmo January 2010 (has links)
Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores (Telecomunicações). Universidade do Porto. Faculdade de Engenharia. 2010
3

Design of Lighting Control System Using Power Line Carrier Communication

Lin, Yang-Jing 25 August 2010 (has links)
This thesis develops an automatic lighting supervisory system (ALSS) which integrates the broadband power line communication (BPLC). The microprocessor, power line communication module and other hardware/firmware are applied in the ALSS to execute the optimal electric energy and lighting control to improve the energy usage efficiency. The ALSS consists of energy control module, BPLC module, and terminal control center. Energy control module provides the functions of electric power measurement, on/off control and lighting control. Furthermore, bidirectional communication between energy control unit and control center is possible via the usage of BPLC communication module. In this thesis, a terminal control center supports the functions of monitoring, recording and alarming. Also, it can allow users to adjust the setting values of the energy control module. Finally, the proposed ALSS is installed to a real lighting system to verify its effectiveness and value.
4

Development of a distance protection system based on the transputer

Minns, Peter David January 1992 (has links)
A Distance Protection System based on the Transputer has been developed in which the Distance Protection Scheme is modelled in Occam, a parallel processing language designed to support the concept of communicating sequential processes running on the Transputer. Two Data Acquisition arrangements have been investigated, one controlled by an Interfacing Transputer via Link Adaptors, the other making use of existing Protection Data Acquisition equipment controlled by the Interfacing Transputer through Dual Port RAM. In both cases other similar additional Transputer modules are interconnected with the Interfacing Transputer to form a parallel processing system for a Distance Protection Scheme. The Occam model of the Protection System has been developed around a central control program (Harness) which can be easily modified to accommodate different Protection algorithms. In addition the Occam Protection Harness incorporates features to allow it to fail safely or run on a single Transputer version of the Harness should the Transputer network fail. This arrangement provides a new approach in the development of Protection systems using multiple processing elements with an Occam Protection Harness that can accommodate different algorithms and Trip logic schemes. The Thesis describes the design of the system and indicates its performance capabilities and limitations. This research indicates that a full three phase distance protection scheme can be realised using four Transputers running simple short data window impedance calculating algorithms, together with post impedance processing and Trip logic. More complex algorithms will require additional faster Transputers but can be realised using the same Occam Protection Harness.
5

Theoretical prediction of rime ice accretion and snow loading on overhead transmission lines using free streamline theory

Larcombe, P. J. January 1984 (has links)
No description available.
6

3D Reconstruction of 138 KV Power-lines from Airborne LiDAR Data

Xiang, Qing January 2014 (has links)
Due to infrequent and imprecise maintenance inspection in power-line corridors, accidents can be caused by interferences, for instance, surrounding trees. Transmission power-line inspection conventionally relies on the participation of ground personnel and airborne camera to patrol power-lines, and is limited by intensive labour, and difficult working conditions and management. Airborne light detection and ranging (LiDAR) has proven a powerful tool to overcome these limitations to enable more efficient inspection. Active airborne LiDAR systems directly capture the 3D information of power infrastructure and surrounding objects. This study aims at building a semi-automatic 3D reconstruction workflow for power-lines extracted from airborne LiDAR data of 138 kV transmission line corridors (500 m by 340 m) in Nanaimo, BC, Canada. The proposed workflow consists of three components: detection, extraction, and fitting. The power-lines are automatically detected with regular geometric shape using a set of algorithms, including density-based filtering, Hough transform and concatenating algorithm. The complete power-lines are then extracted using a rectangular searching technique. Finally, the 3D power-lines are reconstructed through fitting by a hyperbolic cosine function and least-squares fitting. A case study is carried out to evaluate the proposed workflow for hazard tree detection in the corridor. The results obtained demonstrate that power-lines can be reconstructed in 3D, which are useful in detection of hazard trees to support power-line corridor management.
7

Investigation of broadband over power line channel capacity of shipboard power system cables for ship communications networks

Akinnikawe, Ayorinde 15 May 2009 (has links)
Broadband over Power Line (BPL) technology has garnered significant attention lately due to recent advancements in solid state technologies and channel coding schemes. The successful application of BPL technology for in-home automation and networking has led to suggestions of applying BPL in other systems including ships. The application of BPL technology using the Shipboard Power System (SPS) as a potential communications network for ship automation systems has been proposed, to achieve recent U.S. Navy ship management concepts geared toward reducing ship manning while improving operational efficiency. This thesis presents an analytical model developed to examine the channel response characteristics and estimated throughput capacity of SPS cables. The work used a multiconductor transmission line theory based approach to model the channel response of SPS distribution lines and estimated the channel throughput capacity using a “water-filling” communication technique. This work found that BPL using the SPS holds a strong potential for use as a communications network for ship communication systems.
8

Communication Network Analysis in Smart Grid

Lohani, Satyendra Nath January 2012 (has links)
With the world suffering from energy crisis, Smart Grid is the expanding research topic that deals vigorously with the current problems. It promotes decentralized renewable energy generation system, participate many local energy producers to energy market, adds vehicle to grid (V2G), minimize the energy loss in the electrical system, and participate many active consumers to the real market. It is an emerging project that needs an expert from many fields, thus it opens door of opportunities for many people around the globe. The present thesis deals with the communication scenario in smart grid. Communication is the backbone of Smart Grid and the thesis tries to highlight the available communication technologies for smart grid application. The thesis discuss most profitable communication technologies used for this purpose which are power line communication and wireless communication, in which power line communication aspects and characteristics are covered more than wireless communication for its use are seen more in upcoming days. In all the thesis will outline the opportunities and challenges of power line communication and wireless communication for smart grid application.
9

Investigation of broadband over power line channel capacity of shipboard power system cables for ship communications networks

Akinnikawe, Ayorinde 15 May 2009 (has links)
Broadband over Power Line (BPL) technology has garnered significant attention lately due to recent advancements in solid state technologies and channel coding schemes. The successful application of BPL technology for in-home automation and networking has led to suggestions of applying BPL in other systems including ships. The application of BPL technology using the Shipboard Power System (SPS) as a potential communications network for ship automation systems has been proposed, to achieve recent U.S. Navy ship management concepts geared toward reducing ship manning while improving operational efficiency. This thesis presents an analytical model developed to examine the channel response characteristics and estimated throughput capacity of SPS cables. The work used a multiconductor transmission line theory based approach to model the channel response of SPS distribution lines and estimated the channel throughput capacity using a “water-filling” communication technique. This work found that BPL using the SPS holds a strong potential for use as a communications network for ship communication systems.
10

Investigation of machine vision and path planning methods for use in an autonomous unmanned air vehicle

Williams, Matthew January 2000 (has links)
No description available.

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