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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.
381

Utveckling av skyddsväst för jakthundar mot rovdjursangrepp / Development of a protective vest for hunting dogs against predators attack

Richter, Håkan January 2011 (has links)
Varje år skadas eller dödas hundar av rovdjur i samband med framförallt jakt. Olyckorna leder till debatter angående rovdjurens vara eller inte vara. Detta arbete utreder möjligheterna till skydd för dessa hundar. Skyddsmetoden som utreds är en väst som utlöser en elektrisk puls vid ett angrepp. Tanken är att oavsett var på västen ett angrepp sker så ska en spänningsstöt utlösas vilket ska få angriparen att släppa taget. Arbetet är en vidareutveckling av ett koncept som tagits fram av Prodelox AB i Linköping. Konceptframtagandet följer en systematisk konceptutveckling där arbetet delas in i olika faser för att på ett överskådligt sätt komma fram till en prototyp. Första fasen undersöker hur marknaden ser ut på liknande produkter och mynnar ut i en kravkriterielista där produktens funktionalitet specificeras. Andra fasen delar upp huvudprodukten i mindre grenar som åskådliggörs i ett funktion/medels- träd. Sista fasen genererar ett antal olika koncept som utvärderas varav ett koncept går vidare till prototyptillverkning. Rapporten beskriver arbetet fram till en prototyp där önskade funktioner är implementerade, prototypen kommer ligga till grund för beslut om produkten ska utvecklas vidare fram till en färdig produkt. / Every year dogs are injured or killed by predators in relation to particular hunting. These accidents lead to debates about predators existence. This work investigates the possibilities of protection for these dogs. Protection method that is investigated is a vest that triggers an electric pulse when an attack occurs. The idea is that irrespective of where on the vest the attack takes place a voltage shock is released which will get the attacker to get away. The work is a further development of a concept early developed by Prodelox AB in Linköping. The concept development follows a methodology where the work is divided into different phases in order to clarify the work and finally it ends up with a prototype. The first phase examines how the market looks to similar products and leads up to a specification of requirements where the functionality of the product is specified. Second phase divides the main product in smaller pieces which is illustrated in a function/method-tree. The last phase generates a number of different concepts that is evaluated and one concept goes further to making a prototype. The report describes the work up to a prototype in which the required functions are implemented and the prototype will form the basis for decisions about the products future.
382

High temperature fatigue crack propagation in Inconel718

Sharifimajd, Babak January 2010 (has links)
In this work, three different series of fatigue experiments on INCONEL718 will be discussed. For each type of fatigue experiment, the method of evaluation the raw data obtained at the matrial laboratory will be mentioned. Morover, from the obtained results, the fatigue properties of INCONEL718 will be presented in detail. Subsequently, a discussion of the modeling of the fatigue properties of the material in an isothermal condition will be permormed. For that, three different type om models will be investigated and compared. Furthermore, a FEM model of a specific specimen used for TMF-testing (not to be discussed here) will be presented by which the stress intensity factor values can be evaluated.
383

Implementering av ögonspårning i en virtuell arbetsbänk / Implementation of eye tracking to an immersive workbench

Gottfarb, Jonas January 2010 (has links)
Examensarbetet har omfattat en komplett produktutveckling. Detta har lett till en nyprodukt som företaget SenseGraphics ska vidareutveckla och förhoppningsvis producera. Jobbet har kantats av utmaningar vad det gäller tekniken och de begränsningar företaget satt på projektet. Arbetet inleddes med en förstudie för att skapa förståelse för de produkter som skulle sammanfogas. Sedan to s olika koncept fram och därefter valdes det bästa konceptet ut. Detta koncept modellerades sedan i CAD och ritningarna från det användes för att bygga en prototyp. Examensarbetet avslutades med en presentation hos de inblandade företagen. / This thesis has included a complete product development. It has led to a whole newproduct that SenseGraphics probably will further enhance and in the future take toproduction. The job has been full of obstacles regarding both technical problems andlimitations set by the companies active in the project. The thesis started out with a pilotstudy of the two products that was about to merge together. After that a number ofconcepts emerged and the best one was chosen with some help from different matrices.This concept was then created first as a 3D-model and at last as a full scale prototype. Thethesis was ended by a presentation on both the companies and at Linköpings universitet.
384

A System for Visual-Based Automated Storage Robots

Roll, Jakob January 1999 (has links)
Automated storage systems often rely on that the positions of the pallets are known with high precision. In this thesis, a turnable camera mounted on the robot has been used for handling the situation of approximately known pallet positions. The robot is given the approximate location of a pallet, and its objective is to locate the pallet with a precision that is high enough to be able to approach it from the correct direction and then lift it. For this, a precision of a few centimetres in each direction is needed. A system for locating the pallet from single images, based on rotational symmetry filters, has been developed, and a simple program for controlling the robot has been implemented. These could very well be extended and improved, e.g. by considering multiple images and improving the path planning. The main part of the thesis deals with the image processing part. Other parts of the project, apart from the controller, include implementation of servers controlling the camera and the frame grabber. Some tests have been made, which show fairly promising results.
385

Automatisering av förpackningsprocess

Ottosson, Andreas, Aneros, Johan January 2006 (has links)
The production rate at Octapharma AB, Stockholm is about to increase. The factory will be able to handle 1000 tonne human plasma a year instated of today’s capacity of 350 tonne. Today product packaging is carried out manually, which will be highly inefficient in a larger production scale. To analyze the automation demands a lot of pre-studies. Octapharma AB has given us the opportunity to do a pre-study for a future change within the packing department. The aim of the degree project is: • To study the total material flow for packaging of pharmaceuticals. • Automation of present manually packed pharmaceutical. • Determent if present equipment can be used in automation. • Increase the packaging and controls efficiency. The objective of the degree project is: • Find appropriate suggestions for new machines in pharmaceutical product packaging. • To find a suitable placement for machines in allotted area. • Achieve a short and efficient process time. • Suggest a material flow. • The report shall contain a Swedish user requirements specification. High quality products are very important in pharmaceutical industry and failure is not an option. Packaging demands accuracy. There might be a risk of error in human control performances with devastating consequences if failure occurs. Products may not be packed with the wrong leaflet or stamped with the wrong label. The degree project results in a pre-study to an upcoming project for Octapharma AB. The report contains a Swedish and an English user requirements specification (URS). The report also contains a proposition of logistic on the packaging department. The logistics includes machine placements, a storage and handling of order documentation. Other materials concerning the project are attached as appendixes with the final report. Highly important advantages with the project are: • Considerable capacity increase. • Possible future extension of the packaging line. A two gears secondary bulk packaging line can be connected to the existing machines. • The quality control will improve and fulfil GMP-requirements. • Octapharma AB will be able to increase there production capacity considerably. / På Octapharma AB i Stockholm ska produktvolymen ökas. Fabriken ska kunna hantera upptill 1000 ton plasma istället för dagens 350 ton per år. En del av begränsningen idag är att paketeringen sker manuellt. Lösningen för att öka kapaciteten är en automatisering av förpackningsprocessen. Att genomför en automatisering kräver mycket förstudier vilket är tidskrävande. Av den orsaken har Octapharma AB givit oss möjligheten att genomföra en förstudie för kommande förändringar på paketeringsavdelningen. Syftet med examensarbetet är: • Studera det totala materialflödet för paketeringen av läkemedel. • Automatisering av den nuvarande manuella förpackningen av läkemedel. • Undersöka om nuvarande utrustning går att använda i automationen. • Effektivisera paketeringen och kontrollen. Målet med examensarbetet är: • Ge förslag på nya maskiner för paketering av läkemedel. • Hitta lämpligt förslag för placering av maskiner på tilldelad yta. • Få en kort och effektiv processtid. • Föreslå ett materialflöde. • Arbeta fram en kravspecifikation för automatiserad produktion. Produkter med hög kvalitet är ett måste i läkemedelsbranschen, fel får absolut inte förekomma. Paketering kräver väldigt stor noggrannhet och många kontroller. När människan kontrollerar finns risk för en felkälla vilket bör undvikas. Människan kan fela någon gång och då kan det få förödande konsekvenser. Produkt får absolut inte paketeras med fel bipack eller etiketteras med felaktig etikett. Examensarbetet resulterar i en förundersökning till ett projekt för Octapharma AB i Stockholm. Rapporten innehåller en kravlista och en URS (User requirements specification). Rapporten innehåller även ett förslag om hur logistiken kan se ut på packavdelningen. Logistiken infattar maskinplaceringar, närlager samt dokumentationshantering. Övrigt material rörande projektet bifogas som bilagor med slutrapporten. Viltigaste fördelarna med projektet är: • Kapaciteten ökas avsevärt. • Förslaget möjliggör vidareutbyggnad i framtiden. Med två växlar kan en sekundär bulkpaketering kopplas in med befintliga maskiner. • Kvalitetskontrollen skulle bli bättre och även uppfylla GMP-kraven. • En effektivisering av denna grad skulle betyda att Octapharma kan öka produktionstakten avsevärt.
386

Matematisk modellering av industriell luftridå : En jämförelse av effektivitet och elprisets påverkan av driftskostnader / Mathematical Modeling of Industrial Air Curtain : A comparison of efficiency and the electricity price’s affect on running costs

Eriksson, Manne January 2006 (has links)
Det svenska elpriset har de senaste åren stigit kraftigt och förutspås öka ytterliggare under kommande år. Huvudorsaken är avregleringen av den europeiska elmarknaden som påbörjats. Detta har medfört att svenska företag börjat intressera sig för att minska sin elanvändning och på så sätt bevara sin konkurrenskraft gentemot företag på kontinenten. Ett vanligt sätt för att spara energi är att installera en luftridå vid en dörr eller port mot angränsande lokal eller omgivning med annan temperatur. Genom att rikta plana luft¬strömmar med hög hastighet vid porten reduceras möjligheten för de olika luftvolymerna att blandas. Luftridån skyddar därmed mot drag och bevarar lokalens ursprungliga temperatur vilket förbättrar den termiska komforten. En väl fungerande luftridå fyller därmed dubbla funktioner. Den här rapporten är ett examensarbete utförts för Boxholm Stål i samarbete med avdelningen Energisystem, IKP, Linköpings tekniska högskola. Uppgiften är att undersöka flödet och effektiviteten hos en luftridå på en industriell port vid Boxholm Stål. Genom att konstruera en simuleringsmodell baserad på luftridån och validera den ska effektiviteten beräknas. Vidare kommer modellen modifieras för att skapa alternativa konfigurationer vilkas effektivitet kan jämföras med den ursprungliga modellen. Arbetet ska även ge kunskap om hur ett framtida elpris kommer att påverka energikostnaden för driften av luftridån. För att utföra dessa beräkningar användes ett verktyg för matematisk modellering av strömning, CFD. Programvarorna Gambit och Fluent har använts för att skapa modellerna samt utföra och presentera de numeriska beräkningarna. Resultaten visar att en väl konfigurerad luftridå kan både förbättra arbetsklimatet och minska driftkostnader för uppvärmning av lokalen. Jämförelser mellan modellerna visar på stor skillnad i effektivitet beroende på luftridåns placering i förhållande till porten samt den vinkel som luften blåses från inloppet. Enbart genom att modifiera vinkeln för det befintliga inloppet kan driftkostnaderna reduceras med över 60 % jämfört med en oskyddad port utan luftridå. Elprisets påverkan av driftskostnaderna är mycket stor då en dåligt konfigurerad luftridå drar ut stora mängder luft ur lokalen som måste ersättas med uppvärmd luft. En modifierad vinkel på luftridån kan minska driftkostnaderna trots ett framtida ökat elpris. För en luftridå placerad ovanför porten är inloppets vinkel av större betydelse än lufthastigheten. Den optimala vinkeln för inloppet ligger mellan 20 och 30 grader oberoende av en lufthastighet. / The Swedish electricity price has rapidly increased during the last years and is predicted to further increase in the coming years. The main reason is the deregulation of the European electricity market which has begun. As a result Swedish companies have become interested in decreasing their use of electricity to maintain their competitiveness towards foreign companies. A common way to save electricity is to install an air curtain at a door or gate between an adjacent premises or surroundings with different temperature. By aiming plane jets with high velocity at the gate, the different air volumes possibility to mix is reduced. The air curtain therefore protects against draft and maintains the temperature of the premises which improves the thermal comfort. An air curtain working properly can both improve working environment and save energy. This report is a final thesis performed for Boxholm Stål in cooperations with the department of energy systems, IKP, Linköping University. The main goal is to examine the flow and efficiency of an air curtain for an industrial gate at Boxholm Stål. By developing and validating a simulation model based on a real air curtain, the efficiency can be estimated. Furthermore, the model will be modified to create alternative configurations which will be compared with the original model. The thesis will also bring knowledge of how a future electricity price will affect the energy costs for operating the air curtain. To perform these calculations, CFD, a tool for mathematical modeling of fluids was used. The computer programs Gambit and Fluent were used to create the models, perform and present the numerical calculations. The result shows that an air curtain working correctly can both improve the working conditions and reduce the operating costs for heating the premises. Comparisons between the models show large differences in efficiency depending of the positions of the air curtain relative to the gate and the angle at which the air is ejected from the inlet. Solely by modifying the angle for the existing inlet, the operating costs can be reduced by over 60 % compared to a gate without an air curtain. The electricity price’s influence on the operating costs is very large since a poorly operating air curtain is pulling large quantities of air, from the premises to the surroundings, which has to be replaced by heated outdoor air. A modified angle on the air curtain can reduce the operating costs even for a higher electricity price in the future. For an air curtain placed above the gate, the angle of the inlet is of greater importance than the air velocity. The optimal angle for the inlet is between 20 and 30 degrees independent of the air velocity.
387

Strategic Decision Bias by Role in Failed Technology Projects

Pence, Kenneth Rosson 25 June 2003 (has links)
MANAGEMENT OF TECHNOLOGY STRATEGIC DECISION BIAS BY ROLE IN FAILED TECHNOLOGY PROJECTS KENNETH ROSSON PENCE Thesis under the direction of David M. Dilts This empirical research examines how personnel, from different levels of an organization, reach decisions to terminate technical projects. Termination decisions are often considered failures and this research investigates strategic decision-making using failure as an outcome measure. Upper management personnel (executives) with the authority to cancel a technical project and the middle management (project managers) who manage the day-to-day operations of the project are surveyed in phase one of this research to determine what, if any, biases may have affected the decision to terminate a project under their control. Information gathering (scanning and interpretation) and environmental factors (importance, resources, complexity), leading to the decision to terminate a project, are also examined from an individualistic, not a monolithic, viewpoint among innovative technology organizations. Termination decisions are shown not to be related to the scale of a project but that different levels of the organization use different decision weighting levels with regard to project termination. Additionally, hindsight and sunk-cost biases are clearly shown by the two levels of decision-makers within an organization. Phase two of the research develops a model from two concurrent case studies portraying how bias affects project outcome perceptions.
388

Life Cycle Extension Strategies For Legacy Systems

Sellars, Autumn 15 July 2004 (has links)
This paper examines how the characteristics of a system determine the appropriate method that should be used for its life cycle extension. Such systems are termed legacy systems because they are approaching the end of their useful life, preventing them from maintaining their operational objective. Legacy systems were examined because they are expensive to maintain, can pose environmental hazards, and can hinder an organizations performance if not addressed adequately. My study developed a model to identify characteristics of legacy systems and the methods that should be used to extend the life of a legacy system possessing those particular characteristics. The model was evaluated by examining an example legacy system; a missile system in the defense industry; and noting the characteristics associated with it. These characteristics were then used to compare the method the organization chose to extend the life of its system with the method of life extension our model suggested it use. The study used case study research and pattern matching to evaluate its results; which determined if the model correctly predicted the life extension method the organization should chose. Theses results indicate the model can be used to suggest appropriate methods for life extension of legacy systems.
389

THE EFFECTS OF UNIVERSITY TECHNOLOGY COMMERCIALIZATION PRACTICES ON LICENSING INCOME - A COMPARATIVE STUDY

Lashley, Kisha 22 July 2004 (has links)
This thesis focuses on comparing the effects of university technology commercialization practices on their licensing incomes. "High Output" and "High Activity" universities were selected from top U.S. research universities based on the level of resources that are invested in the technology transfer process, as opposed to the level of income generated as a result of licensing activities. We use the multiple case study method,consisting of four "High Outcome" and four "High Activity" universities. The principles of real options theory are used to compare and contrast the technology commercialization processes of the two groups, based on the premise that universities that employ a real options perspective in their technology transfer decisions, will have greater licensing incomes. Based on interviews with technology transfer directors at the universities in the sample, we conclude that the most critical factors affecting licensing income are faculty involvement in the technology marketing process and the level of evaluation of the feasibility of start-up opportunities, prior to engaging in such investments.
390

Life Cycle Extension Stategies for Legacy Systems

Matthews, Ben 12 December 2004 (has links)
This paper analyzes the characteristics of legacy systems and examines how those characteristics can be used to determine the correct method of life cycle extension. A legacy system is a system that is approaching or already at a point where it is no longer of use to an organization, preventing the group from maintaining its operational objective. Legacy systems are important to study because they are expensive to maintain and can hinder an organizations performance if not addressed adequately. This study developed a model that will identify the characteristics of a legacy system and the methods that should be used to extend the life of that legacy system. The model was evaluated using case study research to analyze an example of a legacy system; a guidance system for a missile from the defense industry. The characteristics of the legacy system were analyzed to predict the appropriate method to use for life extension. The method was compared with the organizations life extension method for the guidance system to determine model accuracy. Evaluating the results using simple pattern matching determined if the model could predict the correct life extension strategy. The results indicated that the model can be used to aid in deciding what method or methods could best be used for life extension of a legacy system.

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