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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.
401

BSR Prestandaverktyg / BSR Performance tool : Prestandamätning via diagnosuttag över CAN / Performance measure via diagnostic socket over CAN

Sjöberg, Andreas January 2009 (has links)
This abstract describes the bachelor degree thesis in computer technology at Växjö University. The company BSR in Växjö has requested an application that can measure a cars performance, with attributes like acceleration times and engine power estimation. The communication between car and computer is via the USB port on the computer and the OBD-II socket on the car with the network protocol CAN, controller area network. Cars from VAG have been the primary focus group and the application has been tested on a Volkswagen Passat CC from 2009. The system is developed in the programming language C# in the environment Visual Studio with the framework .NET. This report describes the network protocol CAN, which is an essential part in understanding how thecommunication works. Also approach, analyze and implementation is described. / Denna rapport beskriver ett examensarbete för högskoleingenjörsexamen i datorteknik vid Växjö universitet. Företaget BSR i Växjö har önskat ett program som kan mäta en bils prestanda, med attribut som accelerationstider och effektuppskattning. Kommunikationen mellan bil och dator sker via USB-port på datorn och OBD-II-uttag på bilen med protokollet CAN, controller area network. Bilar från VAG har i första hand varit målgruppen och programmet har testats på en Volkswagen Passat CC från 2009. Systemet har utvecklats i programspråket C# och i utvecklingsmiljön Visual Studio med ramverket .NET. Rapporten beskriver nätverksprotokollet CAN, vilket är en väsentlig del i att förstå hur kommunikationen går till. Även tillvägagångssätt, analys och implementering beskrivs.
402

Nätverksövervakning av trådlösa accesspunkter / Network monitoring of wireless access points

Heino, Felix January 2016 (has links)
Syftet med examensarbetet är att analysera, implementera och utvärdera metoder för nätverksövervakning av trådlös kommunikationsutrustning i företaget Fibras nätverk. I dag sköts driften av cirka 2300 accesspunkter i Västerås stads trådlösa nätverk av Fibra. I nätverket ingår ett antal Wireless LAN Controller (WLC), vars uppgift är att hantera och konfigurera alla accesspunkter. Varje WLC kan hantera upp till 400 accesspunkter och sköter exempelvis autentiseringen av användarna. Dessutom finns det en Whats Up Gold server, vars uppgift är att samla in information om det trådlösa nätverket. Själva nätverksövervakningen presenteras i ett webbgränssnitt för drift personalen på Fibra. Examensarbetet utvärderar vilka delar av nätverket som bör övervakas, vilken information som ska samlas in och hur resultatet av övervakningen ska presenteras för drift personalen på Fibra. Dessutom görs en utvärdering av hur kommunikationen mellan Whats Up Gold servern och WLC sker bäst. Det nätverksövervakningsprogram som Fibra valt använda är Whats Up Gold. Examensarbetet inkluderar dock samtliga aspekter av nätverksövervakningsproblemet, inte bara de som ingår i programmet Whats Up Gold. Resultatet av implementationen innebär att driftpersonalen på Fibra får en särskild vy i Whats Up Gold webbgränssnitt. Den används för att felsöka och för att få en översikt av det trådlösa nätverket. Personalen får också tillgång till en larmvy, där WLC och berörda accesspunkter visas vid eventuella driftstörningar. Larmfunktionen i WLC skickar automatiskt SMS och e-mail till personal som har beredskap. Lösningen för att göra kommunikationen möjlig mellan server och WLC görs med en PBR (Policy Based Routing). En PBR är en teknik för att göra routing beslut baserat på diverse kriterier som är konfigurerade av en administratör. Genom att Fibra inför bra nätverksövervakning kommer antalet oplanerade driftstopp minska och tillgängligheten öka. Det innebär också att eventuella nätverksfel upptäcks snabbare och felsökningen i nätverket blir betydligt lättare. Nätverksövervakning sparar följaktligen både pengar och tid för ett företag som Fibra. / The purpose of this study is to analyse, implement and evaluate methods for network monitoring of wireless communication in the company Fibra. Today, Fibra managed the operation of around 2,300 access points in Västerås. The network includes a number of Wireless LAN Controller (WLC), whose task is to manage and configure all access points. Each WLC can have up to 400 access points and manage, for example, authentication of users. A servers job is to collect information from the wireless network and monitoring the result and present it in a web interface for the administrators. The thesis evaluates which parts of the network that should be monitored and what information should be gathered and how the results of the monitoring will be presented to the user. There should also be an evaluation of how the communication between the server and the WLC should be done. The network monitoring tools Fibra select to use is Whats Up Gold. The work, however, includes all aspects of the network management problem, not just those included in the program Whats Up Gold. The result of implementation means that the operating staff at Fibra received a special view of Whats Up Gold's web interface, used to troubleshoot and get an overview of the wireless network. The staff will also have access to an alarm view, where the WLC and the access points displayed on any incident. The alarm function of the WLC automatically sends SMS and e-mail to personal on duty. The solution to make communication possible between the server and the WLC is made with a PBR (Policy Based Routing). A PBR is a technology to make routing decisions based on various criteria that are configured by an administrator. By implementing network monitoring, the number of unplanned downtime is reduced and availability increased. It also means that any network failure is detected faster and troubleshooting the network becomes much easier. Network Monitoring consequently saves both money and time to a company such as Fibra.
403

Rollen som verksamhetscontroller i statliga myndigheter

Cehaja Lundqvist, Carina January 2016 (has links)
I problemdiskussionen lyfts att litteraturen och forskningen utgår från att en controller är en ekonom som arbetar med ekonomistyrning. Enligt min erfarenhet stämmer inte detta för verksamhetscontrollers i statliga myndigheter. Syftet med uppsatsen är att öka kunskapen om rollen som verksamhetscontroller i statliga myndigheter. Forskningsfrågorna är vilka krav ställer myndigheterna vid rekrytering av verksamhetscontrollers och hur beskriver de arbetsuppgifterna? Vad innehåller tertialuppföljningarna? Metoden har varit att genom en diskursanalys studera innehållet i tertialuppföljning på Socialstyrelsen, Statens institutionsstyrelse och Tullverket. Dessutom har myndigheternas rekryteringsannonser som avser verksamhetscontroller analyserats. Slutsatsen är att arbetsuppgifterna för verksamhetcontrollers på myndighetsnivå är likartade och det ingår inte ekonomiska arbetsuppgifter. De förefaller dock ha olika mandat. Arbetsuppgifterna på avdelnings-/ kompetenscenternivå skiljer sig mellan och inom myndigheterna och inte heller dessa verksamhetscontrollers har ekonomiska arbetsuppgifter. Kraven som ställs på utbildning och erfarenhet har stor spännvidd och ibland har man krav på att den sökande ska ha ekonomisk bakgrund. Min slutsats är att rollen som verksamhetscontroller på avdelnings-/ kompetenscenternivå är under utveckling och att rollen på myndighetsnivå är tydligare. / In literature and research the definition of a controller is an economist working with financial control. According to my knowledge this is not correct for controllers focused on operations management in government agencies The purpose of this thesis is to increase the knowledge of the role as a controller focused on operations management in state agencies. The questions to be answered are what demands does government agencies have when they recruit operations management controllers and how do they describe the  assignments? What is included in the four month follow ups? The method has been by discourse analysis study the content in the four month follow ups at the National Board of Health and Welfare, the National Board of Institutional Care and the Swedish Customs. In the thesis the agencies recruitment ads for controllers focused on operations management is also analyzed. The conclusion is that the assignments for controllers focused on operational management on the agency-wide level is similar between the agencies and few financial assignments are included. The assignments for the lower levels differ within and between the agencies and financial assignment are not included. The controllers at the agency-wide level seem to have different mandates between the agencies. The agencies demands for education and experience varies widely and some of the ads have demands for a background in  finances. My conclusion is that the controller at the department level is under development and the role at the agency-wide level is more distinct.
404

Optimal demand response from home energy management system : modeling and benefits for distribution networks

Althaher, Sereen January 2015 (has links)
The increasing levels of renewable generation and the electrification of transport and heating as parts of the movement towards low-carbon energy systems to cope with climate change will place significant challenges on the electricity system to facilitate the way towards future low carbon energy systems in a cost effective way and ensure secure power delivery. New solutions and higher levels of flexibility are required than currently exist in order to reduce the integration costs of low carbon generation and demand technologies. Price-based demand response in residential sector is considered as one of these potential solutions. However, a certain level of automation is required to reduce both the uncertainty in the consumer response and the complexity for consumers to react to the price signal. This thesis presents a comprehensive and general residential optimization-based Automated Demand Response (ADR). The modelling of home appliances has been extensively developed to include all the classifications proposed in the literature, namely, deferrable and thermal in addition to new groups of critical and fully curtailable loads. The operations of the appliances are controlled in response to dynamic price signals to reduce the consumer’s electricity bill whilst minimizing the daily volume of curtailed energy and therefore considering the user’s comfort level. To avoid shifting most portion of consumer demand towards the least price intervals, which could create network issues due to loss of diversity, higher prices are applied when the consumer’s demand goes beyond a power threshold level. The arising mixed integer nonlinear optimization problem is solved in an iterative manner rolling throughout the day to follow the changes in the anticipated price signals and the variations in the controller inputs while information is updated. The results from different case studies show the effectiveness of the proposed controller to minimize the household’s daily electricity bill while preserving comfort level as well as preventing creation of new least-price peaks. This thesis also proposes a two-stage distribution-planning framework to assess the benefits of the proposed ADR models in response to a location-specific time of use Distribution Use of Systems Charge (DUoSC) on the required investments to connect future low-carbon technologies. The network investments and the satisfaction of consumers in terms of energy curtailment are both quantified. The first stage aims to generate location-specific time of use price signals for all users in the network, which represents their contributions in future network investments due to congestion and security constraints. The second stage relates to a group of ADR controllers at residential premises that aims to minimise the daily energy payment whilst maximising consumer comfort in response to the corresponding price signal produced from the first stage.
405

A Novel Fuzzy Logic Based Controller For Power System Stabilizers And FACTS Devices

Majumder, Ritwik 07 1900 (has links) (PDF)
No description available.
406

Arduino Based Hybrid MPPT Controller for Wind and Solar

Assaad, Michael 12 1900 (has links)
Renewable power systems are becoming more affordable and provide better options than fossil-fuel generation, for not only the environment, but a benefit of a reduced cost of operation. Methods to optimize charging batteries from renewable technologies is an important subject for off-grid and micro-grids, and is becoming more relevant for larger installations. Overcharging or undercharging the battery can result in failure and reduction of battery life. The Arduino hybrid MPPT controller takes the advantage of solar and wind energy sources by controlling two systems simultaneously. The ability to manage two systems with one controller is better for an overall production of energy, cost, and manageability, at a minor expense of efficiency. The hybrid MPPT uses two synchronous buck DC-DC converters to control both wind and solar. The hybrid MPPT performed at a maximum of 93.6% efficiency, while the individual controller operated at a maximum 97.1% efficiency when working on the bench test. When designing the controller to manage power production from a larger generator, the inductor size was too large due to the frequency provided by the Arduino. A larger inductor means less allowable current to flow before the inductor becomes over saturated, reducing the efficiency of the controller. Utilizing a different microcontroller like the PIC16C63A produces a much faster frequency, which will reduce the inductor size needed and allow more current before over saturation.
407

Optimized maintenance budget planning for DB Cargo locomotives

Niedecken, Timon January 2021 (has links)
In a regional railway signalling system, object controllers are the devices responsible for controlling Track Side Equipment and act as interfaces for TSE with the interlocking computer and the Traffic control system. However, associated cabling (signal and power cabling) and civil works pose a major capital investment and it is a source of significant Capital and Operational expenses, particularly in rural areas, where accessibility andconnectivity to power grid and to the interlocking are a problem. Furthermore, cables/signalling equipment are exposed to sabotage and theft in such areas. This can increase the total Life Cycle Cost even further. The Shift2Rail research programme, which was initiated by the European Union and railway stakeholders, tries to address this issue, and revamp the Object Controller concept through the project “TD2.10 Smart radio connectedwayside object controller”, where the aim is to develop a Smart Wayside Object Controller (SWOC). A SWOC is capable of wireless communication between central interlocking and TSE as well as decentralization of interlocking logic. These innovations can reduce the cabling required, increase the availability of diagnostic data, thus reducing maintenance and operational costs and can lead to power saving by utilizing local power sources. The most important impact of the SWOC is a significant reduction of CAPEX, OPEX and of total LCC for an installation utilizing SWOCs, instead of typical OCS.  This work focuses on estimating the LCC of a SWOC system and to compare it with a conventional OCS by developing an LCC model that covers both cases, as well as to use this model to examine when it is more profitable to implement a SWOC, instead of an OCS system. This is done by utilizing LCC analysis and combining a variety of methods in a parametric study. To that extend, a thorough analysis of a modern regional railway signallingsystem, as well as the basis for LCCA are being discussed. At the same time, both OC and SWOC systems are being described and factors affecting their cost discussed.  The methodology is comprised of the LCC modelling part as well as the collection of methods and techniques used to calculate the LCC of OC/SWOC systems and to estimate the costs of different sub-models and parameters of the process. For the modelling process, the station of Björbo was chosen, which operates under ERTMS-R system, but for the sake of the analysis it is assumed that the typical base system in place is an OCS and together withthe existing track layout and equipment it is used as the basis of the analysis. Finally, the formed LCC model is being used in a parametric study to examine how the LCC is affected by using OC or SWOC as well as how LCC responds to changes in parameters such as number of OC/SWOC, traffic density and local power installation cost for the Björbo station. / I ett regionalt järnvägssignalsystem är utdelar de enheter som ansvarar för att kontrollera spårutrustning och fungerar de som gränsyta för spårutrustning med ställverksdatorn och tågtrafikledning systemet. Dock, tillhörande kablar (signalkablar ock kraftkablar), samt anläggningsinfrastruktur utgör en stor kapitalinvestering och de är en källa till märkbar kapitalkostnad och driftskostnader, särskilt på landsbygdsområden, där tillgänglighet och anslutning till elnätet och ställverket är problematisk. Dessutom, kablar och signalutrustning utsätts för stöld och sabotage i sådana områden. Detta kan öka den totala livscykelkostnaden ytterligare. Shift2rail forskningsprogram, som genomförs av EU och järnvägsintressenter, försöker att ta itu med problemet och modernisera utdelar konceptet genom projektet “TD2.10 Smart Radio Connected Wayside Object Controller”, där målet är att utveckla en Smart Spårutrustning Utdelar, så kallade SWOC. En SWOC har kapacitet för trådlös kommunikation mellan central ställverket och spårutrustning, samt decentralisering av satällverkslogiken. Dessa innovationer kan minska nödvändig kabeldragning, öka tillgängligheten av diagnostiska data, vilket minskar underhålls- och driftskostnader och kan leda till energibesparing genom att använda lokala kraftkällor. Den viktigaste effekten av SWOC är en betydande minskning av kapitalkostnader, driftskostnader och totala livscykelkostnaden för en installation som använder SWOC istället för typiska utdelningsystemet. Detta examensarbete fokuserar på att uppskatta LCC för ett SWOC-system och jämföra det med en konventionell utdelingsystem genom att utveckla en LCC-modell som täcker båda fallen, samt att använda denna modell för att undersöka när det är mer lönsamt att implementera en SWOC istället av ett typiskt utdelingsystem. Detta görs genom att använda LCC-analys och kombinera en mängd olika metoder i en parametrisk studie. För att göradetta genomförs en grundlig analys av ett modernt regionalt järnvägssignalsystem, samt grunden för livscykelanalys. Samtidigt beskrivs både ett typiskt utdelingssystem - och SWOC-system samt faktorer som påverkar deras kostnad deskuteras. Metoden består av LCC-modelleringsdelen samt insamling av metoder och tekniker som används för att beräkna LCC för OC / SWOC-system och för att uppskatta kostnaderna för olika delmodeller och parametrar för processen. För modelleringsprocessen valdes stationen i Björbo, som arbetar under ERTMS-R-systemet, men för analysens skull antas att det typiska bassystemet på plats är en typisk OCS och tillsammans med befintlig planritning ochkabelplan är används som grund för analys. Slutligen används den bildade LCC-modellen i en parametrisk studie för att undersöka hur LCC påverkas genom att använda OC eller SWOC samt hur LCC reagerar på förändringar i parametrar såsom antal OC / SWOC, trafiktäthet och lokala kraftinstallationskostnader för Björbo-stationen.
408

Simulátor dopravních infrastruktur a situací / Simulator of Traffic Infrastructures and Situations

Švaňa, Petr January 2018 (has links)
The aim of this master's thesis is to develop a simulation system using the Siemens sX traffic controllers configurations. The system is composed of two separate applications. The first one uses the existing platform SUMO as a source of simulation data and is also used as a server. The second is a web-based application for creating and editing simulation situations and also for visualisation of simulation data from the server. The introduction to the topic of traffic engineering and the dynamic traffic control is discussed first. The description of the design and implementation of the simulation application directly follows. In the next part the design and implementation of the web-based application  is discussed. The last part of the thesis describes the testing of the whole system.
409

Adaptivní regulátory pro systémy s dopravním zpožděním a jejich porovnání s klasickými pevně nastavenými regulátory. / Adaptive controllers for systems with time delay and its comparison with classical controllers.

Faltus, Ivo January 2013 (has links)
Master thesis is focused on the philosophy of design adaptive controller. In the theoretic part are described parts of the adaptive controller, which belongs parts as online identification by recursive least-squares method and PSD controller, which can set its parameters according to identified system (use Z-N method). The part of control system with transport delay is situated at the conclusion of the theoretic part, there are focused on Smith predictor. Practical part is focused on verification of all algorithms, which was performed on models and real systems.
410

Adaptivní regulátory pro systémy s dopravním zpožděním a jejich porovnání s klasickými pevně nastavenými parametry regulátorů. / Adaptive controllers for systems with time delay and its comparison with classical controllers.

Krykorka, Daniel January 2015 (has links)
Master thesis is focused on the philosophy of design adaptive controller. In the theoretic part are described parts of the adaptive controller, which belongs parts as online identification by recursive least-squares method and PSD controller, which can set its parameters according to identified system (use Z-N method). The part of control system with transport delay is situated at the conclusion of the theoretic part, there are focused on Smith predictor. Practical part is focused on verification of all algorithms, which was performed on models and real systems.

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