Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2008. Includes bibliographical references (leaves 67-72). / Distributed wireless sensor networks (DWSNs) are applied in a variety of applications that can enhance the quality of human life or even save lives, such as in fire monitoring, where DWSN microsensors relay the exact location of the fire to water sprinkler actors to automatically extinguish the fire. Batteries are currently the predominant source of energy in DWSNs. one of the key obstacles in the adoption of DWSN technology is the limited lifetime of batteries in microsensors. Recharging or replacing depleted batteries can significantly increase costs in DWSNs. The aim of this study is to address the power challenge in DWSNs by proposing a sixteen-element equiangular spiral rectenna to ahrvest ambient microwave energy to supply indoor DWSNs. The study concludes that this rectenna model has the potential to generate power that enables long periods of operation of the DWSNs without human intervention in the power manageement process, thus reducing maintenance and administration costs. The efficiency of the rectenna model was tested in an anechoic chamber. Efficiency test results indicated that the highest efficiency of 2% for the rectenna model was achieved as 2 GHz for an ambient power of -6 dBm across a 1 K ohm load resistence. The study further concludes that the current rectenna model size of sixteen elements is a limiting factor for the deployment of DWSNs.

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Smart home automation is the dwelling bridge of smart grid technology, as it integrates the modern home appliances power consumption information over communication networks in the smart grid system. Among all the appliances, Heating, Ventilation and Cooling (HVAC) systems is one of the most primary concerns. Since a great amount of power consumption is contributed by these HVAC systems. Traditionally, HVAC systems run at a fixed schedule without automatic monitoring and control systems, which causes load variation, fluctuations in the electricity demand and inefficient utility operation. In this thesis, we propose a Finite State Machine (FSM) system to model the air condition working status to acquire the relationship between temperature changing and cooling/heating duration. Finally, we introduce the Zigbee communciation protocol into the model, the performance analysis of the impact of end-to-end delay over HVAC systems is presented.

In order to improve simulation performance and integrate simulation resources among geographically distributed locations, the concept of distributed simulation is proposed. Several types of distributed simulation standards, such as DIS and HLA are established to formalize simulations and achieve reusability and interoperability of simulation components. In order to implement these distributed simulation standards and manage the underlying system of distributed simulation applications, Grid Computing and Cloud Computing technologies are employed to tackle the details of operation, configuration, and maintenance of the simulation platforms in which simulation applications are deployed. However, for modelers who may not be familiar with the management of distributed systems, it is challenging to create a simulation-run-ready environment that incorporates different types of computing resources and network environments. In this thesis, we propose a new multi-layered cloud-based scheme for enabling modeling and simulation based on different distributed simulation standards. The scheme is designed to ease the management of underlying resources and achieve rapid elasticity, providing unlimited computing capability to end users; energy consumption, security, multi-user availability, scalability and deployment issues are all considered. We describe a mechanism for handling diverse network environments. With its adoption, idle public resources can easily be configured as additional computing capabilities for the local resource pool. A fast deployment model is built to relieve the migration and installation process of this platform. An energy conservation strategy is utilized to reduce the energy consumption of computing resources. Security components are also implemented to protect sensitive information and block malicious attacks in the cloud. In the experiments, the proposed scheme is compared with its corresponding grid computing platform; the cloud computing platform achieves a similar performance, but incorporates many of the cloud's advantages.

This work embraces two different manufacturing processes: pultrusion androtational moulding. One (pultrusion) is concerned with manufacture with athermosetting composite while the other is concerned with manufacture of anunfilled thermoplastic. The connecting theme is one of energy usage in manufacturewith these processes. While a large number of comprehensive computer models of pultrusion havebeen generated, most are focussed on the prediction of the temperature andconversion distributions within the profile; by contrast, the analysis presented here isdirected towards the prediction of the duty cycle of the mould heaters as a first stepin recognising the significance of the energy consumed in the process. The results ofthe model are compared with experimental measurements of the duty cycle of anindustrial machine. The nature of this particular investigation was predominantlyapplied and in particular directed towards industrial use. For this reason, the modelwas created in MATLAB, a software package which is relatively more accessible tothe reinforced plastics industry than FE packages. The project involved extensivemodelling and experimentation. It is shown that the line speed could be increased significantly by preheatingthe profile before it enters the die. For example, line speed for one particular profilewas increased from 0.4m/min to 0.5 m/min by using a pre-heater set at 80°C. Thiswork also showed that the specific energy consumption of the process was 0.2kWh/kg to 0.3 kWh/kg; under different line speeds and operating conditions. Thiswas achieved by measuring the duty cycle of the heaters on the die. This increase inline speed means a saving of up to 30 % of the specific energy consumption in thepultrusion. The energy theme continues through the work on rotational moulding. It isshown that the specific energy consumption in rotational moulding can be reducedby up to 70% by direct heating of the mould by using electrical resistance heatersinstead of current method of using hot air to heat the mould. The finite elementmodel showed that this alternative heating method is capable of producing asuniform a heat distribution on the surface of the mould as the current heating systemby using cyclic heating.

This thesis presents tha findings of an investigation into the use of energy, between the years 1975 and 1984, in five of the major energy-intensive industries in South Africa. Energy use in all economic sectors, from 1964 to 1974, was surveyed in the report "Energy Utilisation in South Africa", published by the Department of Planning and the Environment in 1978. As this report showed the major primary industries to be the largest single users of energy in South Africa, it was decided to isolate a number of major energy-intensive industries for investigation in this study. The 1979 Census of Manufacturing showed five industrial sectors to have consumed 41% by value of the total industrial energy consumption in that year, and it is those with which this thesis is concerned. The five industries are: The Structural Clay Products Industry, The Portland Cement Industry, The Glass Making Industry, The Iron and Steel Industry, The Pulp and Paper Industry.

This report is aim to compared building standard of Chengdu city and Stockholm, as well as find out the suitable energy-saving scenario for two places. To simulate the total energy consumption of logistics building, energy software named design builder will be introduce to calculate. Some of other analysis will be implemented at the same time, including economic analysis, environment analysis and thermal comfort analysis.