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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.
11

Support Maintenance of Design Automation Systems - A Framework to Capture, Structure and Access Design Rationale

Poorkiany, Morteza January 2015 (has links)
The ability to innovate and launch customized products that are well matched to customer demands is a competitive factor for many manufacturing companies. Development of highly customized products requires following an engineer-to-order business process to allow the products to be modified or adapted to new customers’ specifications, which brings more value to the customer and profit to the company. Design of a new product variant involves a large amount of repetitive and time consuming tasks but also information handling activities that are sometimes beyond human capabilities. Such work that does not rely so much on creativity can be carried out more efficiently by applying design automation systems. Design automation stands out as an effective means of cutting costs and lead time for a range of well-defined design activities and is mainly considered as a computer-based tool that processes and manipulates the design information. Adaptation and variant design usually concern generating a new variant of a basic design, which has been developed and proved previously, according to new customer’s demands. In order to efficiently generate a new variant, a deep understanding of the previous design is essential. Such understanding can be achieved by access to the design rationale explaining the reasons and justifications behind the design. Maintenance of design automation systems is essential to retain their usefulness over time and adapt them to new circumstances. New circumstances are, for example, introduction of new variants of existing products, changes in design rules in order to meet new standards or legislations, or changes in technology. To maintain a design automation system, updating the design knowledge (e.g. design rules) is required. Use of design rationale will normally become a necessity to allow a better understanding of the knowledge. Consequently, there is a need of principles and methods to enable capture, structure, and access design rationale. In this study, a framework for modeling design knowledge and managing design rationale in order to support maintenance of design automation systems is presented. Managing of design rationale concerns enabling capture, structure, and access to design rationale. In order to evaluate the applicability of the framework, the findings are tested through design automation systems in two case companies. / Impact / Adapt
12

Managing design rationale in the development of product families and related design automation systems

Poorkiany, Morteza January 2017 (has links)
As the markets’ needs change rapidly, developing a variety of products that meet customers’ diverse needs is a competitive factor for many manufacturing companies. Development of highly customized products requires following an engineer-to-order business process to allow the products to be modified or adapted to new customers’ specifications, which brings more value to the customer and profit to the company. The design of a new product variant involves a large amount of repetitive and time-consuming tasks but also information handling activities that are sometimes beyond human capabilities. Such work that does not rely so much on creativity can be carried out more efficiently by applying design automation systems. Design automation stands out as an effective means of cutting costs and lead time for a range of well-defined design activities and is mainly considered as a computer-based tool that processes and manipulates the design information. Variant design usually concern generating a new variant of a basic design, that has been developed and proved previously, according to new customer’s demands. To efficiently generate a new variant, a deep understanding of the intention and fundamentals of the design is essential and can be achieved through access to design rationale—the explanation of the reasons and justifications behind the design. The maintenance of product families and their corresponding design automation systems is essential to retaining their usefulness over time and adapting them to new circumstances. Examples of new circumstances can include the introduction of new variants of existing products, changes in design rules to meet new standards or legislations, or changes in technology. To maintain a design automation system, updating the design knowledge (e.g. design rules) is required. The use of design rationale will normally become a necessity for allowing a better understanding of the knowledge. Consequently, there is a need for principles and methods that enable the capture and structure of the design rationale and sharing them with the users. This study presents methods and tools for modeling design knowledge and managing design rationale in order to support the utilization and maintenance of design automation systems. Managing design rationale concerns enabling the capturing, structuring, and sharing of design rationale. The results have been evaluated through design automation systems in two case companies. / Att kunna erbjuda kundanpassade produkter har blivit allt viktigare för många tillverkande företag. Utformningen av en ny produktvariant involverar en stor mängd repetitiva och tidskrävande uppgifter men även informationshanteringsaktiviteter som ibland är bortom mänskliga möjligheter. Sådant arbete som inte förlitar sig så mycket på kreativitet kan genomföras mer effektivt genom att använda designautomatiseringssystem. Designautomatisering framstår som ett effektivt sätt att minska kostnader och ledtid för en rad väldefinierade designaktiviteter och betraktas huvudsakligen som ett datorbaserat verktyg som analyserar och syntetiserar designinformationen. Variantdesign handlar vanligtvis om att skapa en ny variant av en grundläggande design, som har utvecklats och bevisats tidigare enligt nya kunders krav. För att effektivt skapa en ny variant är en djup förståelse för designens avsikt och grundläggande uppbyggnad avgörande och kan uppnås genom tillgång till ”design rationale”- förklaringen av skälen och motiveringarna bakom designen. Underhållet av produktfamiljer och deras motsvarande designautomatiseringssystem är viktigt för att behålla användbarheten över tid och anpassa dem till nya omständigheter. Exempel på nya omständigheter kan innefatta införande av nya varianter av befintliga produkter, ändringar av designregler för att uppfylla nya standarder, lagstiftningar eller tekniska ändringar. För att upprätthålla ett designautomatiseringssystem krävs uppdatering av designkunskapen (t ex designregler). Användningen av design rationale kommer normalt att bli en nödvändighet för att ge en bättre förståelse av kunskapen. Följaktligen finns det ett behov av principer och metoder som möjliggör fångande och strukturering av design rationale och dela dem med användarna. Denna studie presenterar metoder och verktyg för modellering av designkunskap och hantering av design rationale för att stödja utnyttjande och underhåll av designautomatiseringssystem. Vid hantering av design rationale gäller det att göra det möjligt att fånga, strukturera och dela med sig av design rationale. Resultaten har utvärderats genom att undersöka effekterna av dem i designautomationssystem i två företag.
13

Comparison of Wireless Communication Technologies used in a Smart Home : Analysis of wireless sensor node based on Arduino in home automation scenario

Horyachyy, Oleh January 2017 (has links)
Context. Internet of Things (IoT) is an extension of the Internet, which now includes physical objects of the real world. The main purpose of Internet of Things is to increase a quality of people’s daily life. A smart home is one of the promising areas in the Internet of Things which increases rapidly. It allows users to control their home devices anytime from any location in the world using Internet connectivity and automate their work based on the physical environment conditions and user preferences. The main issues in deploying the architecture of IoT are the security of the communication between constrained low-power devices in the home network and device performance. Battery lifetime is a key QoS parameter of a battery-powered IoT device which limits the level of security and affects the performance of the communication. These issues have been deepened with the spread of cheap and easy to use microcontrollers which are used by electronic enthusiasts to build their own home automation projects. Objectives. In this study, we investigated wireless communication technologies used in low-power and low-bandwidth home area networks to determine which of them are most suitable for smart home applications. We also investigated the correlation between security, power consumption of constrained IoT device, and performance of wireless communication based on a model of a home automation system with a sensor node. Sensor node was implemented using Arduino Nano microcontroller and RF 433 MHz wireless communication module. Methods. To achieve the stated objectives of this research following methods were chosen: literature review to define common applications and communication technologies used in a smart home scenario and their requirements, comparison of wireless communication technologies in smart home, study of Arduino microcontroller technology, design and simulation of a part of  home automation project based on Arduino, experimental measurements  of execution time and power consumption of Arduino microcontroller with RF 433 MHz wireless module when transmitting data with different levels of security, and analysis of experimental results. Results. In this research, we presented a detailed comparison of ZigBee, WiFi, Bluetooth, Z-Wave, and ANT communication technologies used in a smart home in terms of the main characteristics. Furthermore, we considered performance, power consumption, and security. A model of a home automation system with a sensor node based on Arduino Nano was described with sleep management and performance evaluation. The results show that the battery lifetime of Arduino in a battery-powered sensor node scenario is determined by the communication speed, sleep management, and affected by encryption. Conclusions. The advanced communication strategy can be used to minimize the power consumption of the device and increase the efficiency of the communication. In that case, our security measures will reduce the productivity and lifetime of the sensor node not significantly. It’s also possible to use symmetric encryption with smaller block size.
14

Inteligentní dům pro seniory / Intelligent house for elderly people

Piši, Daniel January 2010 (has links)
Tato diplomová práce se zabývá systémem automatizace domácnosti umožňujícím ovládání domácích spotřebičů prostřednictvím běžné televize. Systém využívá standardu X10 a bezdrátové technologie ZigBee. Řídicí software staví na OS GNU/Linux a systému domácího kina MythTV. V rámci této diplomové práce byla vyvinuta aplikace zprostředkující komunikaci mezi MythTV a hardwarem. Modulární koncept postavený na dynamicky zaváděných modulech dělá tuto aplikaci snadno rozšiřitelnou a použitelnou i mimo předkládaný automatizační systém. Za účelem testování a demonstrace funkčnosti byl dále navržen bezdrátový teploměr a převodník VGA na SCART.
15

Síťová komunikace po napájecím vedení / Power-line network communication

Sláčik, Ján January 2016 (has links)
The master’s thesis is dealing with PLC technology and its modem realization based on several types of standards by using commercially available integrated circuits. This projects also describes fundamentals and prerequisites for building the PLC network fulfilling the European standard CENELEC. The work further describes designed system concept, which serves as the automated system for the appliances connected to an electrical network. Components are selected for implementation and then is introduced concrete solution and implementation power-line network. Within the work are then other parts, that together form a system concept. Work includes the hardware and software implementation and a description of the options implemented system.
16

Home Automation System : A cheap and open-source alternative to control household appliances / Automation i hemmet : en ekonomisk lösning med öppen källkod

Ruwaida,, Bassam, Minkkinen, Toni January 2013 (has links)
This project revolves around creating a home automation system prototype with the main focus being the ability to lock/unlock a door through the internet. The system consists of a central device, a server and an Android application.The central device is a microprocessor, in this case, a Raspberry Pi that connects to the Internet and receives an order to control a motor which in turn turns the lock with the help of gears. The ability to rotate the motor in both directions is achieved by the use of an H-bridge. The server manages users and devices, and handles the communication between the application and the central device. Users and devices are stored in a database on the server. The application is a frontend which presents the user with a list of devices to interact with.The main prototype where the Raspberry Pi acted as a central device was abandoned due to time and resource constraints. It was instead used to control the motor directly. This brought up some problems concerning powering the device using batteries. The software of the prototype is mostly working but due to the same time limitations not all planned features could be implemented.
17

Alternativa reglermetoder för en energieffektiv byggnad / Alternative control methods for an energy efficient building

Herrlin, Emma January 2017 (has links)
Ungefär 60 % av den totala energianvändningen för uppvärmning (inklusive varmvatten) i Sverige går åt till att värma upp flerbostäder och lokaler, vilket ger en indikation på att det finns potential att minska energianvändningen ytterligare genom att hitta alternativa metoder för styr- och reglering av befintliga värmesystem. En viktig faktor oberoende av vilken metod som används är att veta byggnadens dynamiska egenskaper. Det finns en rad olika metoder på marknaden för att kunna minska energianvändningen och en del av dem är välbeprövande medan andra fortfarande är på forskningsnivå. Den beprövade metoden är prognosstyrning vilket också utvärderades vidare i examensarbetet genom en studie av tidigare utförda arbeten inom området. En gemensam och viktig faktor för att kunna spara energi för uppvärmning i byggnader är att veta byggnadens tidskonstant, även kallad värmetröghet. För att påvisa dess betydelse utfördes simuleringar i ett program som heter TEKNOsim som är utvecklat av Chalmers tekniska högskola. Resultatet från simuleringarna som utfördes för 6 olika scenarier visade att den stora faktorn som påverkade byggnaden var internvärmen från belysning, apparater och personer. En yttre påverkande faktor som också hade betydelse var solavskärmning för fönsterna vilket gav en jämnare rumstemperatur. Då simuleringarna anpassades till två olika driftfall för ventilationssystemet till ”kontorstid” och ”utanför kontorstid” höll sig rumstemperaturen inom ramen för högsta och lägsta temperatur under tiden då kontoret var bemannat. En annan metod som användes var en litteraturstudie för arbeten inom området prognosstyrning. För de arbeten som valdes ut undersöktes två olika leverantörer som är marknadsledande i Sverige, eGain och Kabona. I snitt visade resultaten en besparing på 10–15% för uppvärmningskostnaderna men den individuella spridningen för eGains prognosstyrning var stor. Vissa fastigheter hade ingen besparing alls medan andra hade en besparing på 26%. Den stora spridningen berodde antagligen på att det nya systemet endast varit igång i 6 månader då studiens utfördes, vilket är för kort tid för att få några tillförlitliga resultat. För Kabonas tjänst Ecopilot var resultaten mer jämna.
18

Un système multi-agents à base de composants pour l’adaptation autonomique au contexte – Application à la domotique / Component based multi-agent system for autonomic adaptation to the context - Application to home automation

Hamoui, Mohamad Fady 13 December 2010 (has links)
Les environnements domotiques sont des environnements ubiquitaires dans lesquels des équipements domestiques, disséminés dans une habitation, fournissent des services utilisables à distance au travers d'un réseau. Des systèmes domotiques sont proposés pour permettre aux utilisateurs de contrôler les équipements en fonction de leurs besoins.Idéalement, ces systèmes orchestrent l'exécution des services fournis par les équipements pour réaliser des services complexes. Mieux encore, ces systèmes doivent s'adapter à la variété des environnements en termes d'équipements et des besoins des utilisateurs. Ils doivent également pouvoir s'adapter dynamiquement, si possible de manière autonome, au changement de leur contexte d'exécution (apparition ou disparition d'un équipement, évolution des besoins).Dans cette thèse, nous apportons une réponse à cette problématique avec SAASHA, un système domotique multi-agents à base de composants. La combinaison de ses deux paradigmes permet de gérer l'adaptation à trois niveaux : présentation (interfaces utilisateur),organisation (architecture du système) et comportement (architecture interne des agents).Les agents perçoivent le contexte et ses changements. Les utilisateurs se voient proposer une vue dynamique du contexte leur permettant de définir des scénarios personnalisés sous forme de règles. Les agents se répartissent les rôles pour réaliser les scénarios. Ils modifient dynamiquement leur architecture interne grâce à la génération, au déploiement et à l'assemblage de composants pour se doter de nouveaux comportements de contrôle des équipements et des scénarios. Les agents collaborent ainsi pour exécuter les scénarios. En cas de changement, ces trois niveaux d'adaptation sont mis en oeuvre de manière dynamique et autonome pour maintenir la continuité de service. Un prototype de SAASHA, basé sur les standards industriels UPnP et OSGi, a été développé pour évaluer la faisabilité de notre proposition. / Home automation environments are ubiquitous environments where domestic devices, scattered throughout a home, provide services that can be used remotely over a network. Home automation systems are proposed to enable the users of controlling the devices according to their needs. Ideally, these systems orchestrate the execution of the services provided by the devices to achieve complex services. Even more, these systems must adapt to the variety of environments in terms of devices and users needs. They must also be able to adapt dynamically, if possible in an autonomous manner, to the changes of their execution context (appearance or disappearance of a device, changing needs).In this thesis, we provide an answer to this problematic with SAASHA, a multi-agent home automation system based on components. The combination of these two paradigms enables managing the adaptation on three levels: presentation (user interface), organization (system architecture) and behavior (internal architecture of agents). The agents perceive their context and its changes. The Users are offered a dynamic view of the context allowing them to define custom scenarios as rules. The agents divide the roles among them to realize the scenarios. They modify dynamically their internal architecture throughout the generation, deployment and assembly of components to adopt new device control behaviors and scenarios. The agents collaborate to execute the scenarios. In case of a change, these three levels of adaptation are updated dynamically and autonomously to maintain the service continuity. A SAASHA prototype, based on UPnP and OSGi industry standards, has been developed to assess the feasibility of our proposal.
19

A service-oriented approach to embedded component-based manufacturing automation

Kaur, Navjot January 2012 (has links)
This thesis is focused on the application of Component-Based (CB) technology to shop floor devices using a Service Oriented Architecture (SOA) and Web Services (WS) for the purpose of realising future generation agile manufacturing systems. The environment of manufacturing enterprises is now characterised by frequently changing market demands, time-to-market pressure, continuously emerging new technologies and global competition. Under these circumstances, manufacturing systems need to be agile and automation systems need to support this agility. More specifically, an open, exible automation environment with plug and play connectivity is needed. Technically, this requires the easy connectivity of hardware devices and software components from different vendors. Functionally, there is a need of interoperability and integration of control functions on different hierarchical levels ranging from field level to various higher level applications such as process control and operations management services. A potential solution is to realise a modular and reconfigurable automation system, based on a platform of reusable components; while simultaneously reducing the number of unique components. For designing such reusable components, a component-based technology has been used in current thesis. The automation components created are active and distributed entities interacting through their data, event and service ports. To communicate these entities, this thesis focuses on applying SOA and WS at device level. SOA and WS have already been proven successful in linking business applications. If SOA can be applied at shop floor using the embedded devices, it can enable entirely new automation architecture based on peer-to-peer interactions between autonomous devices. The adoption of this SOA-WS approach at shop floor level would enable a seamless integration of higher level business applications and shop- floor level system. This will also provide a loosely coupled message-oriented service in embedded device networks and geographically distributed automation system. SOA can be implemented using Web Services on the embedded devices, which will provide even greater exibility and interoperability because WS is platform neutral. This SOA-WS approach will enable end users to operate and maintain the supplied system easily. A key aim of this thesis is to examine if the adoption of SOA-WS at the embedded control devices can provide the same level of message speed and reliability as the current control systems. It is expected that the desired distributed, loosely coupled and reconfigurable automation system can be formed by a network of these collaborative autonomous SOA-WS based devices using an open control platform. This approach has been experimentally evaluated both in terms of quantity and quality using various parameters involved in the design, implementation, evaluation and recon guration of SOA-WS based automation systems. This has been done using the Ford Festo test rig located at the Manufacturing System Integration Research Institute of Loughborough University. The mechanisms on this test rig represent control problems typically associated in engine assembly and handling machines. Therefore, the result of experimental studies performed on this test rig can be considered applicable to real manufacturing applications.
20

Proposta de integração do sistema de automação de subestações retificadoras do sistema metrô-ferroviário brasileiro. / Proposal for the integrated automation of the brazilian subway system rectifier substations.

Sousa, Carlos Alberto de 28 April 2010 (has links)
Esta dissertação apresenta uma proposta de integração sistêmica da automação das subestações retificadoras do sistema metrô-ferroviário brasileiro. Esta dissertação também apresenta os ganhos de confiabilidade que podem ser obtidos, caso a mesma seja implementada, e a priorização da eficiência de operação do sistema em questão. A motivação deste trabalho deve-se à necessidade de atender à perspectiva de aumento de demanda de energia elétrica nos processos de expansão e modernização deste sistema, amplamente usado pela população brasileira. A partir do estudo e análise do atual sistema de automação existente nas subestações do sistema metrô-ferroviário brasileiro, da arquitetura de hardware e software, foi possível investigar como a integração dos dados pertencentes aos sistemas de controle da subestação e do Centro de Controle Operacional CCO - pode permitir o aumento da confiabilidade e da flexibilidade de operação. Para quantificar estes ganhos de confiabilidade é apresentado o desenvolvimento do modelo de confiabilidade de Markov aplicado ao sistema de automação de subestações retificadoras. A metodologia utilizada procedeu ao levantamento e análise das ocorrências abertas nos anos de 2006, 2007 e 2008 nas subestações retificadoras do metrô de São Paulo, calculando o seu MTBF (Mean Time Between Failures). O estudo conclui que o ganho de confiabilidade é significativo no que se refere à melhoria do transporte público com a aplicação da integração da automação das subestações retificadoras. / This dissertation there presents a proposal for the integrated automation of the Brazilian subway system rectifier substations, supported on the gains of reliability which may be obtained in case it is implemented, and in the improvement of the efficiency of operation of the system open to question. The inquiry was supporting in the necessity of paying attention to the perspective of increase of demand of electric energy in the processes of expansion and modernization of this system, widely used by the Brazilian population. From the study and analysis of the current system of existent automation in the substations of the system Brazilian subway, of the architecture of hardware and software, was possible to investigate like the integration of the pertaining data to the systems of control of the substation and of the Centre of Operational Control CCO can allow the increase of the reliability and of the flexibility of operation. To quantify these profits of reliability there is presented the development of the model of reliability of Markov devoted to the system of automation of rectifying substations. The used methodology proceeded to the lifting and analysis of the incidents when they were opened in the years of 2006, 2007 and 2008 in the rectifier substations of the subway of Sao Paulo, calculating the MTBF (Mean Time Between Failures). The study ends that the profit of reliability is significant in what it refers to the improvement of public transport with the application of the integration of the automation of the rectifying substations.

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