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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.
51

Analýza a návrh rozšiřitelnosti MES řešení v potravinářské společnosti / MES Solution in Food Company: Analysis and Expansion Proposal

Soukup, Milan January 2012 (has links)
The effective use of information system MES (Manufacturing Execution System) in the food company is the main topic of this master's thesis. The modularly built system provides valuable support of the production process on operational level. The thesis concentrates on the analysis of already implemented standard solution in the company's factory. Main goal is to propose expansion of the functioning area to the already existing solution, aiming for effective use of energy resources. It was necessary, in order to be able to achieve the goal, to get familiar with the complex corporate IT/ICT construction in alignment with the company's energy concept. The proposed solution is leaning on application of internal MES project methodology, leading to exact specification of energy component in the factory production frame. The thesis conclusions, besides the proposed solution itself should serve as an argument about the efficiency of starting MES system in other production factories of the company.
52

Planejamento e Políticas Públicas: uma análise sobre a Gestão Energética Descentralizada em âmbito municipal no Brasil. / Planning and Public Policy: an analysis of the Decentralized Energy Management at the municipal level in Brazil.

Collaço, Flavia Mendes de Almeida 30 January 2015 (has links)
A Gestão Energética Descentralizada é uma forma de gestão dos recursos energéticos cujas primeiras publicações referentes ao tema datam dos anos 1980, no entanto, foi verificado um crescimento do desenvolvimento de estudos e aplicações do conceito na prática de forma substancial somente em tempos recentes (anos 2000). A Gestão Energética Descentralizada é tratada sob uma infinidade de termos e conceitos, e também pode ser aplicada com graus diferentes de descentralização como em vilas, quarteirões, bairros, distritos e estados. Tal conceito está fortemente atrelado ao combate das emissões de Gases de Efeito Estufa, busca pela inserção das fontes de energia renováveis nas matrizes, conservação de energia e eficiência energética, e pela associação entre planejamento urbano, ou das cidades, ao dos sistemas energéticos. Ainda, cabe destacar que nesse modelo de gestão descentralizado- a participação popular e o engajamento dos cidadãos nos processos decisórios e na busca por cidades sustentáveis veem sendo colocado, por muitos pesquisadores do tema, como requisitos indispensáveis ao seu adequado funcionamento. Esta dissertação tem como foco de pesquisa a Gestão Energética Descentralizada em âmbito municipal e seu desenvolvimento nas cidades do Brasil. Dessa forma, foi realizada uma revisão bibliográfica sobre o estado da arte do desenvolvimento da Gestão Energética Descentralizada Municipal no Brasil e no mundo, abarcando principalmente questões do planejamento e de políticas públicas como transparência e participação popular no desenvolvimento dos Planejamentos Energéticos Locais. O resultado da pesquisa mostra que existe Gestão de Energia Descentralizada Municipal no Brasil com desenvolvimento de Planejamentos Energéticos Municipais, os quais têm como principal instrumento incentivador o subprograma PROCEL-GEM, foco de estudo de caso também desenvolvido nessa pesquisa, que demonstrou que os planejamentos realizados dentro do subprograma estão restritos as unidades consumidoras de energia elétrica dos órgãos e serviços públicos, além disso, foram observados indícios de falta de transparência e participação popular nos processos de planejamento, assim como falta de recursos para a implementação dos projetos formulados em tais documentos. / Early publications on Decentralized Energy Management, which is a form of energy resources management, date back to the 1980s, however, a substantial increase in the development of such studies and applications of the concept was verified only in recent times (2000s). The Decentralized Energy Management is treated under a multitude of terms and concepts, and can also be applied with varying degrees of decentralization such as in villages, blocks, neighborhoods, districts and states. This concept is close linked to themes like Greenhouse Gases mitigation, integration of renewable energy sources in the energy matrix, energy conservation, energy efficiency and the relationship between urban planning and the energy system. It is noteworthy that in this management model decentralized the communitys participation and engagement in the decision making in the development of sustainable cities is being pointed out, by many researchers, as an indispensable requirement for the proper functioning of this kind of model. This dissertation focuses on Decentralized Energy Management at the municipal level and its development in the cities of Brazil. Thus, this work performs a state of art review on Decentralized Municipal Energy Management in Brazil as well as in the world, covering mainly planning and public policy issues such as transparency and community participation in the development of local Energy Planning. The results shows that there are Decentralized Municipal Energy Management projects in Brazil which develop Municipal Energy Planning, mostly supported by the PROCEL GEM-subprogram, that is also the case study of this research. Additionally, the results demonstrated that the planning made within this subprogram is restricted to the electricity consumption of public agencies or services. Moreover, were observed indications of a lack of transparency and community participation in the planning process as well as the lack of resources for the implementation of such projects.
53

Planejamento e Políticas Públicas: uma análise sobre a Gestão Energética Descentralizada em âmbito municipal no Brasil. / Planning and Public Policy: an analysis of the Decentralized Energy Management at the municipal level in Brazil.

Flavia Mendes de Almeida Collaço 30 January 2015 (has links)
A Gestão Energética Descentralizada é uma forma de gestão dos recursos energéticos cujas primeiras publicações referentes ao tema datam dos anos 1980, no entanto, foi verificado um crescimento do desenvolvimento de estudos e aplicações do conceito na prática de forma substancial somente em tempos recentes (anos 2000). A Gestão Energética Descentralizada é tratada sob uma infinidade de termos e conceitos, e também pode ser aplicada com graus diferentes de descentralização como em vilas, quarteirões, bairros, distritos e estados. Tal conceito está fortemente atrelado ao combate das emissões de Gases de Efeito Estufa, busca pela inserção das fontes de energia renováveis nas matrizes, conservação de energia e eficiência energética, e pela associação entre planejamento urbano, ou das cidades, ao dos sistemas energéticos. Ainda, cabe destacar que nesse modelo de gestão descentralizado- a participação popular e o engajamento dos cidadãos nos processos decisórios e na busca por cidades sustentáveis veem sendo colocado, por muitos pesquisadores do tema, como requisitos indispensáveis ao seu adequado funcionamento. Esta dissertação tem como foco de pesquisa a Gestão Energética Descentralizada em âmbito municipal e seu desenvolvimento nas cidades do Brasil. Dessa forma, foi realizada uma revisão bibliográfica sobre o estado da arte do desenvolvimento da Gestão Energética Descentralizada Municipal no Brasil e no mundo, abarcando principalmente questões do planejamento e de políticas públicas como transparência e participação popular no desenvolvimento dos Planejamentos Energéticos Locais. O resultado da pesquisa mostra que existe Gestão de Energia Descentralizada Municipal no Brasil com desenvolvimento de Planejamentos Energéticos Municipais, os quais têm como principal instrumento incentivador o subprograma PROCEL-GEM, foco de estudo de caso também desenvolvido nessa pesquisa, que demonstrou que os planejamentos realizados dentro do subprograma estão restritos as unidades consumidoras de energia elétrica dos órgãos e serviços públicos, além disso, foram observados indícios de falta de transparência e participação popular nos processos de planejamento, assim como falta de recursos para a implementação dos projetos formulados em tais documentos. / Early publications on Decentralized Energy Management, which is a form of energy resources management, date back to the 1980s, however, a substantial increase in the development of such studies and applications of the concept was verified only in recent times (2000s). The Decentralized Energy Management is treated under a multitude of terms and concepts, and can also be applied with varying degrees of decentralization such as in villages, blocks, neighborhoods, districts and states. This concept is close linked to themes like Greenhouse Gases mitigation, integration of renewable energy sources in the energy matrix, energy conservation, energy efficiency and the relationship between urban planning and the energy system. It is noteworthy that in this management model decentralized the communitys participation and engagement in the decision making in the development of sustainable cities is being pointed out, by many researchers, as an indispensable requirement for the proper functioning of this kind of model. This dissertation focuses on Decentralized Energy Management at the municipal level and its development in the cities of Brazil. Thus, this work performs a state of art review on Decentralized Municipal Energy Management in Brazil as well as in the world, covering mainly planning and public policy issues such as transparency and community participation in the development of local Energy Planning. The results shows that there are Decentralized Municipal Energy Management projects in Brazil which develop Municipal Energy Planning, mostly supported by the PROCEL GEM-subprogram, that is also the case study of this research. Additionally, the results demonstrated that the planning made within this subprogram is restricted to the electricity consumption of public agencies or services. Moreover, were observed indications of a lack of transparency and community participation in the planning process as well as the lack of resources for the implementation of such projects.
54

Power consumption optimization based on controlled demand for smart home structure / Optimisation de la consommation d'électricité basée sur la demande contrôlée pour la structure de la maison intelligente

Amer, Motaz 27 November 2015 (has links)
Cette thèse propose un concept d'optimisation de la consommation d'énergie dans les maisons intelligentes basées sur la gestion de la demande qui repose sur l'utilisation de système d e gestion de l'énergie à la maison (HEMS) qui est en mesure de contrôler les appareils ménagers. L'avantage de ce concept est l'optimisation de la consommation d'énergie sans réduire les utilisateurs vivant confort. Un mécanisme adaptatif pour une croissance intelligente système de gestion de l'énergie de la maison qui a composé des algorithmes qui régissent l'utilisation des différents types de charges par ordre de priorité pré-sélectionné dans la maison intelligente est proposé. En outre, une méthode pourl'optimisation de la puissance générée à partir d'un hybride de systèmes d'énergie renouvelables (HRES) afin d'obtenir la demande de charge. particules technique d'optimisation essaim (PSO) est utilisé comme l'optimisation algorithme de recherche en raison de ses avantages par rapport à d'autres techniques pour réduire le coût moyen actualisé de l'énergie (LCE) avec une plage acceptable de la production en tenant compte des pertes entre la production et la demande. Le problème est défini et la fonction objective est introduite en tenant compte des valeurs de remise en forme de sensibilité dans le processus d’essaim de particules. La structure de l'algorithme a été construite en utilisant un logiciel MATLAB et Arduino 1.0.5 du logiciel.Ce travail atteint le but de réduire la charge de l'électricité et la coupure du rapport pic-moyenne (PAR). / This thesis proposes a concept of power consumption optimization in smart homes based on demand side management that reposes on using Home Energy Management System (HEMS) that is able to control home appliances. The advantage of the concept is optimizing power consumption without reducing the users living comfort. An adaptive mechanism for smart home energy management system which composed of algorithms that govern the use of different types of loads in order of pre-selected priority in smart home is proposed. In addition a method for the optimization of the power generated from a Hybrid Renewable Energy Systems (HRES) in order to achieve the load demand. Particle Swarm Optimization Technique (PSO) is used as optimization searching algorithm due to its advantages over other techniques for reducing the Levelized Cost of Energy (LCE) with an acceptable range of the production taking into consideration the losses between production and demand sides. The problem is defined and the objective function is introduced taking into consideration fitness values sensitivity in particle swarm process. The algorithm structure was built using MATLAB software and Arduino 1.0.5 Software. This work achieves the purpose of reducing electricity expense and clipping the Peak-toAverage Ratio (PAR). The experimental setup for the smart meter implementing HEMS is built relying on the Arduino Mega 2560 board as a main controller and a web application of URL http://www.smarthome-em.com to interface with the proposed smart meter using the Arduino WIFI Shield.
55

An Energy Management Oriented Analysis: Case Study of a Waste to Energy Plant in Lecco, Italy

Cerra, Noemi January 2019 (has links)
The ISO 50001 standard on energy management systems was released in 2011 with the aim of providing organizations with a standardised guideline for the evaluation and continual improvement of energy performance. Complex structures such as the waste to energy (WTE) sector, which must comply with social, environmental, economic and productivity objectives, can benefit from the development of a compliant energy management system (EnMS). Energy efficiency and energy savings contribute to the mitigation of the heavy cost of such a facility, while the benchmark analysis allows verifying the state of the system and the potential areas for improvement. The energy performance improvements can be valorised on an environmental base, and proper promotion of the process can contribute to the mitigation of social opposition. This thesis reviews the energy performance of a waste to energy facility located in Lecco, Italy, using the information available from the control system already installed in the company. Regression analysis is used to fit linear and polynomial functional forms to the energy consumption data and create the energy baseline for the areas of significant energy use and production with a predictive power of 59 – 92%. The difference among the baseline and the actual energy consumption is proposed as energy performance indicator, in order to appreciate the results of the improvement opportunities, and a set of key performance indicators are evaluated for internal and external benchmarking of the facility. The economic feasibility of a selection of sectorial Best Available Technologies (BATs) and the related energy performance improvement is evaluated, revealing that 2 – 16 M€ can be invested in the system retrofit; the creation of synergies with the facility heating, cooling and electricity demand is also suggested. Lastly, an energy, economic and environmental analysis is suggested as a ranking system for the identified improvement opportunities. The methodology and results of this study are intended to provide a proper energy review for Silea Spa, suggest a review procedure for other WTE facilities willing to develop a compliant EnMS and enrich the literature with a case study on WTE. For the Italian context, which is currently facing difficulties in the modernization of the waste management system (WMS), the ISO 50001 application on WTE facilities offers a unified structure that can be used by the government to map the current status of each facility and develop the legislative framework in accordance to the needs of the WMS, the circular economy and the public opinion. / ISO 50001-standarden för energihanteringssystem släpptes 2011 för att ge organisationer en standardiserad riktlinje för utvärdering och kontinuerlig förbättring av energiprestanda. Komplexa strukturer som sektorn för avfall till energi (WTE), som måste uppfylla målen socialt, miljömässigt, ekonomiskt och produktivt, kan dra nytta av utvecklingen av ett kompatibelt energihanteringssystem (EnMS). Energieffektivitet och energibesparingar bidrar till att mildra den stora kostnaden för en sådan anläggning, medan jämförelseanalysen gör det möjligt att verifiera systemets tillstånd och de potentiella förbättringsområdena. Förbättringen av energiprestanda kan värderas på en miljöbas, och en korrekt främjande av processen kan bidra till att mildra social opposition. Denna avhandling granskar energiprestanda för ett slöseri till en energianläggning i Lecco, Italien, med hjälp av den information som finns tillgänglig från det styrsystem som redan är installerat i företaget. Regressionsanalys används för att passa linjära och polynomiska funktionsformer till energiförbrukningsdata och skapa energigrundnivå för områdena med betydande energianvändning och produktion med en prediktiv effekt på 59-92%. Skillnaden mellan baslinjen och den faktiska energiförbrukningen föreslås som indikator för energiprestanda för att uppskatta resultaten av förbättringsmöjligheterna och en uppsättning nyckelresultatindikatorer utvärderas för intern och extern riktmärkning av anläggningen. Den ekonomiska möjligheten för ett urval av sektorns bästa tillgängliga teknik (BAT) och den därmed sammanhängande förbättringen av energieffektiviteten utvärderas, vilket visar att 2 - 16 miljoner euro kan investeras i systemets eftermontering. skapandet av synergier med anläggningens uppvärmning, kylning och el efterfrågan föreslås också. Slutligen föreslås en energi-, ekonomisk och miljöanalys som ett rankningssystem för de identifierade förbättringsmöjligheterna. Metoden och resultaten av denna studie är avsedda att ge en ordentlig energianalyse för Silea Spa, föreslå ett granskningsförfarande för andra WTE-anläggningar som är villiga att utveckla en kompatibel ENMS och berika litteraturen med en fallstudie om WTE. För det italienska sammanhanget, som för närvarande står inför svårigheter i moderniseringen av avfallshanteringssystemet (WMS), erbjuder ISO 50001-tillämpningen på WTE-anläggningar en enhetlig struktur som kan användas av regeringen för att kartlägga nuvarande status för varje anläggning och utveckla den rättsliga ramen i enlighet med WMS, den cirkulära ekonomins och den allmänna opinionens behov.
56

Developing a dynamic control system for mine compressed air networks / Schalk Willem van Heerden

Van Heerden, Schalk Willem January 2014 (has links)
Mines in general, make use of compressed air systems for daily operational activities. Compressed air on mines is traditionally distributed in two typical fashions. Firstly, direct pipe feed systems for single shafts or compressed air ring networks where multiple shafts are supplied with compressed air from an integral system. These compressed air networks make use of number compressors feeding the ring from various locations in the network. While mines have sophisticated control systems to control these compressors they are not dynamic. Compressors are selected on static priorities for a chosen time period of the day. While this is acceptable for some days it is not always the ideal solution. The compressed air demand of the ring is dynamic and it is difficult to estimate the future need of the system. The Dynamic Compressor Selector (DCS) is described as a solution to this problem. DCS is a computer based control system featuring a Graphical User Interface (GUI). The aim of DCS is to dynamically calculate a control pressure set-point, given the demand for compressed air as well as choose the optimal compressors to supply the given compressed air. This will reduce the power requirement of the compressed air ring as well as reduce compressor cycling. DCS was implemented and tested on a single mine compressed air system. Achieved results were 1.8 MW in electricity savings as well as the added benefit of reduced cycling. This saving results in a cost saving of R3.7 million per annum. The problems and shortfalls of the system are also discussed as well as possible future directions for moving forward. / MIng (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2014
57

Implementing DSM interventions on water reticulation systems of marginal deep level mines / Adriaan Petrus van Niekerk

Van Niekerk, Adriaan Petrus January 2014 (has links)
Because of a continuous increase in the demand for electricity in South Africa the country’s largest electricity utility (Eskom) has been under strain to provide electricity. An expansion programme to generate more electricity has caused a continuous increase in utility costs. Steep electricity tariff increases have forced large electricity consumers, such as the mining industry, to focus on energy efficiency and demand side management (DSM). More recently, large industrial action has affected the marginality of the mining industry in such a way that mining groups were forced to cut down on production cost and even sell mining shafts. A solution has to be found to improve the marginality of these mines. DSM intervention on mine water reticulation systems has shown great promise in the past and has been implemented on many South African mines with great success. Many mines with smaller systems have not been optimised because the priority of DSM intervention was to achieve the largest saving; therefore, larger systems enjoyed priority over smaller systems. This only added to the increased financial pressure on already marginal mines. In this study the operation of a mine water reticulation system will be studied to identify the most efficient DSM interventions to implement. DSM intervention on dewatering-, refrigeration- and water distribution systems will be investigated to get a better understanding of the functions of these operations. Previous project data will be analysed to create tools that would assist in the decision-making process for DSM intervention regarding saving potential, cost benefit and cost implication. This data would ultimately assist in determining a project’s payback period that is used to prioritise DSM intervention applications. A mining group will be analysed to identify possible DSM intervention potential. The systems will be investigated and the best strategy for DSM intervention will be selected. This study will conclude that it is financially feasible to implement DSM interventions on marginal mines’ dewatering systems. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014
58

A needs assessment of the market for resource efficiency and cleaner production services in the Vaal Triangle / Theunis Christoffel Botha

Botha, Theunis Christoffel January 2014 (has links)
Major energy-consuming countries implemented new laws on energy-efficiency during the course of 2013. The new energy-efficiency law make provision for a 16% reduction in energy intensity by 2015 in China. New law in the United States of America requires new fuel-economy standards. European Union law aims for a cut of 20% in energy demand for the countries forming part of the European Union. Japan, with the country's new energy strategy aims to decrease electricity demand with 10% by 2030 as stipulated in the new energy strategy. South Arica is currently experiencing a shortage in electricity generating capacity and operates within its reserve margin. The construction of new power stations is in process to address the shortage but Eskom must finance these assets by increasing the electricity tariff. Electricity prices are predicted to double from 2013 to 2017. In addition to the tariff increases, the Energy Conservation Scheme (ECS) is also planned by Eskom whereby all electricity consumers have to reduce their electricity consumption by 10% or face penalties. Energy efficiency initiatives in South Africa will help meet some of the country's social, economic, and environmental goals. These initiatives are important as they immediately tackle the problem of electricity shortages and are a cost-effective way of increasing available electricity supply. The aim of this study was to determine the need for businesses in the Vaal Triangle to be resource efficient and practice clean production in order to be able to capitalise on that need. With the current knowledge and technology available, Resource Efficiency and Cleaner Production (RECP) will prove to be a future necessity for industry. To determine the perceived readiness towards a green economy contribution is thus of importance. The study did a review on RECP, energy efficiency, supply of energy in South Africa, focus areas for energy efficiency and the benefits thereof. The study discussed energy efficiency incentive schemes and subsidisation funds available in South Africa. The study assessed the primary fields for RECP, the drivers and barriers to RECP and the willingness to participate in RECP initiatives in the Vaal Triangle. The study concluded that there exists a need in the Vaal Triangle for RECP initiatives and that there exists potential for the start of a green economy in the region. The research indicated the reaction towards RECP initiatives to be very positive in the studied region. / MBA, North-West University, Potchefstroom Campus, 2015
59

An integrated sustainability framework for environmental impact reduction in the gold mining industry/ Hendrik Gideon Brand

Brand, Hendrik Gideon January 2014 (has links)
The gold mining industry pollutes both water and air resources in numerous ways. Of these, air pollution from greenhouse gasses inducing climate change poses the highest threat to human existence, with water scarcity as a result of pollution presenting the third highest risk (Mathews, 2007; Akorede et al., 2012; Jones et al., 1988). Water pollution, indirect air pollution and direct air pollution should be mitigated for sustainable gold mining. Environmental impact reduction is achieved by the implementation of effective Environmental Management Systems (EMSs). These systems aim to achieve ISO 14001-compliance by setting targets and implementing a systematic approach to achieving these targets. However, ISO 14001-compliant systems do not ensure environmental impact reduction and give the mine no competitive edge (Hilson & Nayee, 2002). EMSs available are too generic for implementation on gold mines. Reporting on Key Performance Indicators (KPIs) on gold mines should also be improved as it is unclear exactly what values should be reported on. This is due to a general lack of an environmental reporting standard (Jones, 2010). Manpower and expertise to identify and implement projects is limited and the mines need assistance with the implementation of projects to effect resource pollution. Priority for the mines is an emphasis on production and safety rather than environmental impact reduction, so implementing projects to reduce pollution is often neglected. A novel sustainability framework is developed in this study. In this framework a database of electricity- and environmental impact reduction projects is created that can be implemented in the gold mining industry. Projects are automatically identified by monitoring key operational indicators. By involving a third party in the form of an Energy Services Company (ESCO), project funding for these sustainability projects can be attained. This novel approach to environmental impact reduction creates a situation where ESCOs implement these EMSs at a reduced cost to the mines. This reduces the cost of lowering the mine’s environmental impact, while aiding the ESCO in identifying sustainability projects. KPIs from various studies are consolidated to determine exactly what values should be reported on. These values are incorporated into a successful EMS. This allows the availability of all the necessary data for reporting to the Department of Energy (DoE) and the South African National Energy Development Institute (SANEDI) on electricity-savings. Projects are prioritised based on an integrated electricity- and environmental impact reduction payback approach. This approach allows funding options to be assessed for each project individually, based on both electricity- and environmental impact reduction advantages. This allowed the best funding option for each individual project to be determined. Automatic identification of these projects reduces the required manpower and resources to implement sustainability projects. Projects proposed by this study showed a combined energy efficiency reduction of 11.8 MW and achieved a load shift of 15.6 MW. In addition to electricity reduction, these projects also reduced the water usage by 1135 Ml per annum and the carbon dioxide equivalent production by 214 205 ton per annum. The proposed projects were effective at increasing the sustainability of gold mining. It also streamlined the implementation of these projects on gold mines. By applying this framework, sustainability improvements can now be achieved on gold mines worldwide. / PhD (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014
60

The suitability of WiFi infrastructure for occupancy sensing / Melanie Delport

Delport, Melanie January 2014 (has links)
The focus of this study was to investigate an alternative and more cost effective solution for occupancy sensing in commercial office buildings. The intended purpose of this solution is to aid in efficient energy management. The main requirements were that the proposed solution made use of existing infrastructure only, and provided a means to focus on occupant location. This research was undertaken due to current solutions making use of custom occupancy sensors that are relatively costly and troublesome to implement. These solutions focus mainly on monitoring environmental changes, and not the physical locations of the occupants themselves. Furthermore, current occupancy sensing solutions are unable to provide proximity and timing information that indicate how far an occupant is located from a specific area, or how long the occupant resided there. The research question was answered by conducting a proof of concept study with data simulated in the OMNeT++ environment in conjunction with the MiXiM framework for wireless networks. The proposed solution investigated the fidelity of existing WiFi infrastructure for occupancy sensing, this entailed the creation of a Virtual Occupancy Sensor (VOS) that implemented RSS-based localisation for an occupant’s WiFi devices. Localisation was implemented with three different location estimation techniques; these were trilateration, constrained nearest neighbour RF mapping and unconstrained nearest neighbour RF mapping. The obtained positioning data was interpreted by a developed intelligent agent that was able to transform this regular position data into relevant occupancy information. This information included a distance from office measurement and an occupancy result that can be interpreted by existing energy management systems. The accuracy and operational behaviour of the developed VOS were tested with various scenarios. Sensitivity analysis and extreme condition testing were also conducted. Results showed that the constrained nearest neighbour RF mapping approach is the most accurate, and is best suited for occupancy determination. The created VOS system can function correctly with various tested sensitivities and device loads. Furthermore results indicated that the VOS is very accurate in determining room level occupancy although the accuracy of the position coordinate estimations fluctuated considerably. The operational behaviour of the VOS could be validated for all investigated scenarios. It was determined that the developed VOS can be deemed fit for its intended purpose, and is able to give indication to occupant proximity and movement timing. The conducted research confirmed the fidelity of WiFi infrastructure for occupancy sensing, and that the developed VOS can be considered a viable and cost effective alternative to current occupancy sensing solutions. / MIng (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2014

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