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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.
31

Experiment Design for Closed-loop System Identification with Applications in Model Predictive Control and Occupancy Estimation

Ebadat, Afrooz January 2017 (has links)
The objective of this thesis is to develop algorithms for application-oriented input design. This procedure takes the model application into account when designing experiments for system identification. This thesis is divided into two parts. The first part considers the theory of application-oriented input design, with special attention to Model Predictive Control (MPC). We start by studying how to find a convex approximation of the set of models that result in acceptable control performance using analytical methods when controllers with no closed-form control law, for e.g., MPC are employed. The application-oriented input design is formulated in time domain to enable handling of signals constraints. The framework is extended to closed-loop systems where two cases are considered i.e., when the plant is controlled by a general but known controller and for the case of MPC. To this end, an external stationary signal is designed via graph theory. Different sources of uncertainty in application-oriented input design are investigated and a robust application-oriented input design framework is proposed. The second part of this thesis is devoted to the problem of estimating the number of occupants based on the information available to HVAC systems in buildings. The occupancy estimation is first formulated as a two-tier problem. In the first tier, the room dynamic is identified using temporary measurements of occupancy. In the second tier, the identified model is employed to formulate the problem as a fused-lasso problem. The proposed method is further developed to be used as a multi-room estimator using a physics-based model. However, since it is not always possible to collect measurements of occupancy, we proceed by proposing a blind identification algorithm which estimates the room dynamic and occupancy, simultaneously. Finally, the application-oriented input design framework is employed to collect data that is informative enough for occupancy estimation purposes. / <p>QC 20170620</p>
32

Softwarově definovaná domácí automatizace / Software Defined Home Automation

Stupka, Dominik January 2016 (has links)
This thesis is about development and construction of systems for building automation. At the beginning it´s focused on usage of building automation. Short describe used topology of installation and available systems on the market. The second chapter is about designing of hardware’s elements systems. Then it’s describing control unit Raspberry Pi 3, microprocessors for communication and slave modules. For my thesis I am also engaged in interface communication and designing of I/O systems. The third and fourth chapter is describing software equipment’s of the system. The parts of microprocessor firmware and manner of control logic creating and visualization in control unit module are described in details. Last chapter contains the description of construction of testing module and measuring of system parameters.
33

Experimental Study on Low Power Wireless Sensor Network Protocols with Native IP Connectivity for BuildingA utomation

Zhu, Shaoling January 2015 (has links)
The recent development of wired and wireless communication technologiesmake building automation the next battlefield of the Internet of Things. Multiplestandards have been drafted to accommodate the complex environmentand minimize the resource consumption of wireless sensor networks. This MasterThesis presents a thorough experimental evaluation with the latest Contikinetwork stack and TI CC2650 platform of network performance indicators,including signal coverage, round trip time, packet delivery ratio and powerconsumption. The Master Thesis also provides a comparison of the networkprotocols for low power operations, the existing operating systems for wirelesssensor networks, and the chips that operate on various network protocols. Theresults show that CC2650 is a promising competitor for future development inthe market of building automation.
34

Säkerhetsfrågor beträffande Sakernas Internet med fokus på fastighetsinfrastruktur / Security Issues concerning Internet of Things with a focus on Real Estate Infrastructure

Pathan, Sakib, Stenström, Erik January 2015 (has links)
I detta examensarbete görs en analys av säkerheten hos några av de driftundercentraler som används i fastigheter som Riksbyggen förvaltar. Driftundercentralerna används för att kontrollera olika delar i en fastighet, exempelvis belysning och temperatur. I de flesta fall nås respektive driftundercentral via en egen publik IP-adress, medan vissa tillverkare har en molntjänst för sina driftundercentraler. Syftet med examensarbetet har varit att undersöka de olika driftundercentralernas säkerhet, upptäcka brister och ge förbättringsförslag till dessa. Därutöver ges också exempel på hur smarta hem kan byggas upp. Undersökningen har gjorts på flera sätt, dels med hjälp av kontrollerade attacker men även genom att samla information om driftundercentralerna och hur de fungerar. Utifrån de undersökningar som gjorts har ett antal brister kunnat konstateras, bl.a. när det gäller lösenordens styrka och kryptering av dessa. Generella förslag på förbättringar har getts för att minska sårbarheten för eventuella attacker som kan ske i framtiden. / This project presents an analysis of the security regarding some of the controllers which are used in real estates managed by Riksbyggen. The controllers are used to control different parts of a property, such as lighting and temperature. In most cases, the controllers are reached via their own public IP address, while some manufacturers have a cloud service for their controllers. The purpose with this project has been to examine the different controllers’ security, discover weaknesses and provide suggestions for improvements to these. In addition, examples are also given on how smart homes can be built. The study has been made in several ways, partly with the help of controlled attacks but also by gathering information about the controllers and how they operate. Based on the studies that were made, a number of weaknesses have been observed, including passwords’ strength and encryption of these. General suggestions for improvements have been given to reduce the vulnerability for possible attacks that may occur in the future.
35

Estudo sobre o emprego de dispositivos sem fios - wireless na automação do ar condicionado e de outros sistemas prediais. / A study of wireless devices technology application for the automation of the air conditioning and other building systems.

Montebeller, Sidney José 10 July 2006 (has links)
Este trabalho apresenta um estudo de tecnologias de comunicação sem fio e suas aplicações na automação predial. A principal motivação para a elaboração deste trabalho é o uso crescente dessas tecnologias em diversas áreas, principalmente em sistemas de automação industrial, comercial, residencial e predial. O uso de equipamentos como telefones celulares e notebooks, que possuem canais de comunicação sem fio (Bluetooth, 802.11b/g WiFi, etc.), também contribuiu para o aumento do interesse na pesquisa de soluções usando redes sem fio. Inicialmente são apresentadas e estudadas, de forma comparativa, as tecnologias existentes de comunicação sem fio. Em seguida, são apresentados os principais sistemas que podem ser automatizados dentro de um edifício inteligente e também exemplos de aplicações de uso das tecnologias sem fio. A demonstração do uso de dispositivos sem fio foi feita a partir de um protótipo. Esse protótipo foi elaborado com o objetivo de substituir sensores de temperatura de um sistema de ar condicionado. O consumo das baterias e a relação custo-benefício do sistema foram os principais itens avaliados. Este estudo pretende demonstrar que dispositivos sem fio podem ser mais uma opção na automação de edifícios e residências, podendo servir como solução, em vários casos, para problemas de infra-estrutura e de integração dos sistemas de automação. / This work presents a study of the wireless communication technologies and their applications to intelligent building automation systems. The main motivation for this work is the increasing use of wireless technologies in several areas, specifically industrial, commercial, residential and building automation. The use of equipments as cellular telephones and notebooks, provided by wireless communication channels (Bluetooth, 802.11b/g WiFi, etc.), has been contributing to the interest in the research of solutions related to this technology. Initially, the existent commercial technologies of some wireless communication systems are presented and studied, in a comparative way. The main systems that exist inside an automated intelligent building and examples of applications of the wireless technologies are presented. The use of wireless devices was depicted by means from a prototype, which was built up with the scope of substituting the sensor of temperature of an air conditioning system. The consumption of the batteries and the cost-benefit relationship of the system were the main items evaluated with the prototype. This study intends to demonstrate that wireless devices can be an interesting option for the automation of buildings and residences. In several cases, the use of these devices can be a solution for some of the infrastructure problems and for the integration of the automation systems.
36

Estudo sobre o emprego de dispositivos sem fios - wireless na automação do ar condicionado e de outros sistemas prediais. / A study of wireless devices technology application for the automation of the air conditioning and other building systems.

Sidney José Montebeller 10 July 2006 (has links)
Este trabalho apresenta um estudo de tecnologias de comunicação sem fio e suas aplicações na automação predial. A principal motivação para a elaboração deste trabalho é o uso crescente dessas tecnologias em diversas áreas, principalmente em sistemas de automação industrial, comercial, residencial e predial. O uso de equipamentos como telefones celulares e notebooks, que possuem canais de comunicação sem fio (Bluetooth, 802.11b/g WiFi, etc.), também contribuiu para o aumento do interesse na pesquisa de soluções usando redes sem fio. Inicialmente são apresentadas e estudadas, de forma comparativa, as tecnologias existentes de comunicação sem fio. Em seguida, são apresentados os principais sistemas que podem ser automatizados dentro de um edifício inteligente e também exemplos de aplicações de uso das tecnologias sem fio. A demonstração do uso de dispositivos sem fio foi feita a partir de um protótipo. Esse protótipo foi elaborado com o objetivo de substituir sensores de temperatura de um sistema de ar condicionado. O consumo das baterias e a relação custo-benefício do sistema foram os principais itens avaliados. Este estudo pretende demonstrar que dispositivos sem fio podem ser mais uma opção na automação de edifícios e residências, podendo servir como solução, em vários casos, para problemas de infra-estrutura e de integração dos sistemas de automação. / This work presents a study of the wireless communication technologies and their applications to intelligent building automation systems. The main motivation for this work is the increasing use of wireless technologies in several areas, specifically industrial, commercial, residential and building automation. The use of equipments as cellular telephones and notebooks, provided by wireless communication channels (Bluetooth, 802.11b/g WiFi, etc.), has been contributing to the interest in the research of solutions related to this technology. Initially, the existent commercial technologies of some wireless communication systems are presented and studied, in a comparative way. The main systems that exist inside an automated intelligent building and examples of applications of the wireless technologies are presented. The use of wireless devices was depicted by means from a prototype, which was built up with the scope of substituting the sensor of temperature of an air conditioning system. The consumption of the batteries and the cost-benefit relationship of the system were the main items evaluated with the prototype. This study intends to demonstrate that wireless devices can be an interesting option for the automation of buildings and residences. In several cases, the use of these devices can be a solution for some of the infrastructure problems and for the integration of the automation systems.
37

The integration between design and maintenance of office building automation : a decision support approach

Lin, Frank Ching-Shou January 2005 (has links)
This research explores the barriers and limitations of the interaction between building development processes in an attempt of an integrated decision support approach to improve building design for effective maintenance in the field of office building automation. Extensive coverage of literature and practice in office building industry over the last two decades indicates a wide diffusion and application of the information and communication technologies (ICT). While this has resulted in the adoption of advanced system integration in buildings, system redundancy and excessive expenditures are causing a major impact on the overall efficiency and has burdened building owners and occupiers with escalating maintenance costs. This phenomenon stimulates and warrants the re-examination of integrated building development, not just on system integration but also on the interdisciplinary development process integration particularly linking design and maintenance. Studies in this field revealed existing problems such as the inherent professional fragmentation, lack of historical information and service data, the first cost mentality of owners and developers, difficulties in forecasting future conditions and changes early in the design stage. With extensive use of qualitative information, this situation presents a great potential for the development of a decision support system exploring the communication and integration of design and maintenance phases, which has been one of the primary objectives of this research. In addition to literature studies, a questionnaire survey and a case study to identify industry concerns, feasible solutions, and practical procedure oriented approaches through knowledge extractions were carried out. A set of guidelines, a checklist for its implementation and prototype system for computerized decision support to design and maintenance of building automation systems were also produced. These strategic approaches to balance design and maintenance will help facilitate appropriate decision making in the early design stage for sustainable maintenance of buildings.
38

Energianalys av byggnad med installerat ångsystem för matlagningsprocesser : Kan ånga vara mer effektivt än el för matlagning?

Bodell, Erik, Åhlander, Simon January 2017 (has links)
Det finns ett stort behov av att minska energianvändningen i världen. Igenom att minska energibehovet så minskar den negativa miljöpåverkan. I en ständigt växande värld där det byggs i allt snabbare takt så ökar också energibehovet. Igenom att effektivisera befintliga byggnader kan energibehovet stagnera eller till och med minska trots utbyggnaden. Igenom att energieffektivisera så kan mer av den energi som används nyttjas istället för att den ska stå för onödiga förluster. Fortifikationsverket har en restaurangbyggnad de anser använder för mycket energi. Denna byggnad innehåller en restaurang som använder ett ångsystem för matproduktion, vilket gör byggnadens energisystem unikt. För att kunna minska byggnadens energianvändning kartläggs och analyseras den i denna rapport. Denna fallstudie genomförs med en litteraturstudie för att utveckla kunskaperna inom området. Sedan utförs mätningar i byggnaden som därefter analyseras och presenteras så att eventuella avvikelser och brister påpekas. Under arbetets gång upptäcktes att en säkring var felinstallerad för mätningen av elanvändningen till en av ångpannorna. Igenom att ha åtgärdat detta för att kunna fakturera rätt så spar Fortifikationsverket nästan 170 000 kr per år som den ångpannan går. Utöver detta så analyserades ångsystemet och uppskattningar gjordes för att kunna svara på om ånga är effektivare än el för matlagning. Det visar sig att ångsystemet kan vara effektivt om stor mängd mat tillagas. Med hänsyn till nätter, helger och de dagar då mindre mat tillagas så är el-utrustning effektivare eftersom att det helt stängs av när det inte används. Till skillnad från ångsystemet som måste täcka upp för förlusterna för att behålla temperatur och tryck, även när systemet inte används. Igenom att byta ut ångsystemet till motsvarande utrustning som drivs av el skulle det gå att spara 205 MWh/år, enligt uppskattningar. Ångsystemet står för 35% av byggnadens totala elanvändning och är den största posten för energianvändningen och är därför den del som fokuserats mest på. Utöver ångsystemet så analyserades övrig energianvändning för att kunna ge förslag på besparingar. Många av förslagen är grundade på vissa uppskattningar och antaganden vilket måste beaktas. Några konkreta exempel på besparingar som kan göras är att sänka inomhustemperaturen för att spara 50 MWh/år, installera tilläggsfönster för att spara upp till 140 MWh/år, installera effektivare kylaggregat – 200 MWh/år, installera bättre styrning till ventilationen – 110 MWh/år, installera bättre styrning till belysning – 40 MWh/år. / There is a great need to reduce energy use in the world. By reducing energy demand, this reduces the negative environmental impact. In a constantly growing world, where it is built at an ever faster pace, the energy demand also increases. By increasing energy efficiency inexisting buildings, energy requirements may stagnate or even decrease despite expansion. By increasing energy efficiency, more of the energy demand can be used instead of standing for energy losses. Fortifikationsverket has a building they believe use too much energy. This building contains a restaurant that uses a steam system to heat its food, which makes the building's energy system unique. In order to reduce the energy consumption of the building, an energy audit is completed and analyzed in this report. This case study is conducted with a literature study to develop the knowledge in the field. Then measurements in the building are performed which are subsequently analyzed and presented to indicate any deviations and deficiencies. During the work it was discovered that a fuse was incorrectly installed to measure the electricity consumption of one of the boilers. By correcting this in order to be able to bill correctly, Fortifikationsverket saves almost 170,000 SEK per year as the boiler goes. In addition to this, the steam system was analyzed and estimates were made to respond if steam is more effective than electricity for cooking. It turns out that the steam system can be effective if a large amount of food is cooked. Considering nights, weekends and days when less food is cooked, electrical equipment is more effective because it completely turns off when not in use. Unlike the steam system that has to cover the energy losses to keep temperature and pressure, even when the system is not in use. By replacing the steam system with equivalent electrical equipment, it couldsave 205 MWh/year, according to estimates.The steam system accounts for 35% of the building's total electricity demandand is the largest item for energy use and is therefore the most focused area. In addition to the steam system, other energy usage was analyzed to provide energy savings. Many of the proposals are based on certain estimates and assumptions which must be considered. Some examples of savings that can be made is lowering the indoor temperature to save 50 MWh/year, install additional windows to save up to 140 MWh/year, install more efficient cooling units -200 MWh/year, install better ventilation control systems-50 MWh/year, install better controls for indoor lighting -40 MWh/year.
39

Internet of Things based Smart Homes : Security Risk Assessment and Recommendations

Ali, Bako January 2016 (has links)
The Internet of Things (IoT) is an emerging paradigm focusing on the inter-connection of things or devices to each other and to the users. Over time, the most of connections in IoT are shifting from ‘Human to Thing’ to ‘Thing to Thing’. This technology is anticipated to become an essential milestone in the development of smart homes to bring convenience and efficiency into our lives and our homes. But, by bringing this IoT technology into our homes there will be important implications for security in these technologies. Connecting every smart objects inside the home to the internet and to each other results in new security and privacy problems, e.g., confidentiality, authenticity, and integrity of data sensed and exchanged by objects. These technologies are very much vulnerable to different security attacks that make an IoT-based smart home unsecure to live in and therefore it is necessary to evaluate the security risks to judge the situation of the smart homes. For any technology to be successful and achieve widespread use, it needs to gain the trust of users by providing sufficient security and privacy assurance. As in all sectors, maintaining security will be a critical challenge to overcome. As homes are increasingly computerized and filled with devices, potential computer security attacks and their impact on residents need to be investigated. This report uses OCTAVE Allegro Methodology which focuses mainly on information assets and considers containers (technical, physical and people) and conducts a security risk assessment with the goal of highlighting various security flaws in IoT-based smart home, impacts and proposing countermeasures to the identified issues satisfying most of security requirements. Finally, it comes up with some recommendations to the users. The research findings documented into a thesis paper for secure IoT-based smart home systems and the resulted list and recommendations will be some useful contribution which can be used as a foundation for the specification of security requirements. For future work, the assessment will be extended to include more types of smart home applications rather than just typical one. / <p>Validerat; 20160620 (global_studentproject_submitter)</p>
40

Systemsvagheter och systemstyrkor för användandet och utvecklandet av fastighetsautomation : En explorativ intervjustudie av teknologiska innovationssystem inom byggindustrin

Lindberg, Joakim, Viebke, Adam January 2017 (has links)
Buildings today represent a large part of societies energy consumption. The increasing environmental awareness has sparked an interest in lowering building energy consumption and building automation systems has been recognized as an effective way of contributing to a more sustainable society. The purpose of this report is to identify the blocking and driving forces between actors in the construction industry when implementing and developing building automation systems. By understanding the blocking and driving forces of a technology in a system, an understanding can be developed of how the industry should act to increase the usage and development of certain technology. Building automation systems can be said to be a systemic innovation, that is, an innovation that affects more than one actor. As there is more than one actor affected by the innovation, systemic innovations are characterized by the complexity when enforcing it. A tool for understanding problems that different actors’ face is the technological innovation framework. This framework has laid the foundation for the analysis of the system strengths and system weaknesses when implementing and developing building automation. In addition, a literature study on technological innovation systems and systemic innovation has been conducted. By examining and evaluating collected data from 19 expert interviews based on the following seven functions presented in the technological innovation framework, five system weaknesses and four system strengths have been identified. The five system weaknesses are (1). The construction industry´s structure and working methods, (2). Lack of industrial cooperation, (3). The conservative attitude in the construction industry, (4). Limited access and development of human capital, and (5) Weak market incentives. Based on these system weaknesses, a discussion was conducted regarding the importance of coordination between the construction industry’s actors and its different disciplines. With the understanding of the four system strengths, (1). Established marked and proven technology, (2). Strong digitalization trends and positive knowledge development, (3). Increased environmental awareness and, (4). Strong urbanization trends, creates an understanding of what factors that drives the systems forward. / Byggnader representerar idag en stor del av den totala energiförbrukningen i samhället. I takt med en ökad miljömedvetenhet har intresset för att sänka byggnaders energiförbrukning blivit en allt viktigare fråga och fastighetsautomation har uppmärksammats som ett effektivt sätt för att bidra till ett mer hållbart samhälle. Syfte med denna rapport är att identifiera de systemsvagheter och systemstyrkor som finns mellan aktörerna i byggindustrin vid implementering och utveckling av fastighetsautomation. Genom att förstå systemsvagheterna och systemstyrkorna för en teknologi i ett system kan förståelse skapas för hur en industri skall agera för att kunna öka användandet och utvecklingen av en viss teknik. Fastighetsautomation kan sägas vara en systemisk innovation, det vill säga en innovation som påverkar fler än en part. I och med att flera aktörer påverkas av innovationen kännetecknas systemiska innovationer av dess komplexitet att genomföra. Ett verktyg för att förstå de bakomliggande utmaningarna för ett system är det teknologiska innovationsramverket. Ramverket har legat till grund för analysen kring systemstyrkor och systemsvagheter inom området för fastighetsautomation. Till detta har även en litteraturstudie genomförts kring teknologiska innovationssystem samt systemisk innovation. Genom att ha undersökt insamlade data från 19 expertintervjuer baserade på de sju funktionerna som presenterats i det teknologiska innovationsramverket, har fem systemsvagheter och fyra systemstyrkor kunnat identifieras. De fem systemsvagheterna är (B1). Byggindustrins uppbyggnad och arbetssätt, (B2). Bristande industriell samverkan, (B3). Byggindustrins konservativa attityd, (B4). Begränsad tillgång och utveckling av humankapital, och (B5) Svaga marknadsincitament. Baserat på systemsvagheterna förs en diskussion kring vikten av samordning mellan byggindustrins aktörer och discipliner. Med förståelsen för de fyra systemstyrkorna, (D1). Etablerad marknad och beprövad teknik, (D2). Stark digitaliseringstrend och positiv kunskaps tillförsel, (D3). Ökad miljömedvetenhet och (D4). Stark urbaniseringstrend, skapas en förståelse för faktorer som gynnar byggindustrins arbete med fastighetsautomation.

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