Sökresultat:
2182 Uppsatser om Hydropower reservoirs; dam safety; erosion protection; waves; simulation; MIKE 21 Spectral Wave - Sida 65 av 146
Fluid Simulation for Visual Effects
This thesis describes a system for dealing with free surface fluid simulations, and the components needed in order to construct such a system. It builds upon recent research, but in a computer graphics context the amount of available literature is limited and difficult to implement. Because of this, the text aims at providing a solid foundation of the mathematics needed, at explaining in greater detail the steps needed to solve the problem, and lastly at improving some aspects of the animation process as it has been described in earlier works. The aim of the system itself is to provide visually plausible renditions of animated fluids in three dimensions in a manner that allows it to be usable in a visual effects production context. The novel features described include a generalized interaction layer providing greater control to artists, a new way of dealing with moving objects that interact with the fluid and a method for adding source and drain capabilities..
EAS-tagg med fuktsensor : Design och utvärdering av EAS-alarmteknologi för fuktdetektering
Electronic article surveillance (EAS) is widely used in shops and libraries together with an RF-tag attached to the goods or books in order to prevent shoplifting. By implementing the addition of a moisture sensor to the RF-tag, other functions become possible, including the ability to use as an alarm with regards to frozen goods, which have been shipped but which have melted and have, subsequently, refrozen. In- relation to care for the elderly, one time-consuming step involves checking whether there is the necessity for a change of diaper and this can, instead, be based on an RF-tag with an EAS-system alarm. A preliminary investigation was made using the moisture sensors, which involved how the resistance changes when liquid and/or heat is applied. A simulation of the LCCR circuit (RF-tag with the sensor) was conducted in order to determine how the resonance frequency changes for different resistances levels.
Säkerhetsbrytare för Gräsklippare
This thesis describes teh solution of two problems regarding safety on powered lawnmowers; protectning the users from injury when using the lawnmower in slopes, and when cleaning the cutting blade.The task was carried out through initial studies on a representative lawnmower. A generation of ideas followed with an evaluation to select the best solution. The winning concept was further developed to reach acceptable performance. The word resulted in a functioning prototype utilising an original way of detecting inclinations without incorrect signals. It c an serve as a platform for further development into a product.The work gives insightful experience of solving real-world problems, and especially to deal with situations where several variables and their effects are unknownPlease note that several parts of the work are confidential, and have therefore been removed from the thesis..
Analys av nivåproblematik i dränagetank på Ringhals 1
The focus of this project has been on the drainage tank of the reheater on Ringhals 1. This tank has on two previous occasions received such a high water level that the system automatically emergency stopped. For this reason, events and various readings from these two occasions has been specifically studied and analyzed. In order to prove theories about what causes these problems a model of the system was created in the program Dymola. Using simulation results from the model, we have been able to demonstrate how the system's measured values should look likeunder normal conditions with respect to flows, pressures, temperatures, valve positions and water level in the drainage tank.
Borrning och gängning av laxkilar till vågkraftverk med industrirobot
To make wave power more competitive on the market Uppsala University leads projects that examine how to accomplish better efficiency in the production. One of these projects is described in this report and examines whether it is possible to make the production of dovetails more efficient by using an industry robot of type ABB IRB6000 S3 M91. This project is using an already presented working method, from a previous project, which involves that the robot picks up the dovetail and moves against fixed cutting machines where the dovetail will be drilled, threaded and milled. Drilling and threading are the sub operations that will be examined in this project where experiments are made with the presented working method and with equipment from Uppsala University.Experiments show whether it is possible to drill the holes in the dovetail within specifications by using the specific robot and the presented working method. The threading operation is examined theoretically if it is possible to accomplish by using the same working method.
CE-ma?rkning av produkter under byggproduktfo?rordningen
The purpose of this study is to achieve an understanding of how a CE- marking process is conducted and to identify the relevant factors that must be considered in such a process. We have conducted our study at Lo?vhults Svets & Smide AB (Lo?vhults) in Skruv, Sma?land Sweden, which are manufacturing brackets for small covering constructions.To understand how a CE-marking process is conducted several documents and provisions have been reviewed to achieve a basic understanding and insight of the subject. It thus led to that guideline ETAG 015 were studied and the factors to be considered in the CE-marking of brackets were identified. Together with Jan-A?ke Johansson at Lo?vhults we agreed on four different brackets to investigate for a potential CE-marking.
Dynamisk simulering med hjälp av RPS-beräkningar för radiovågors utbredning i urban miljö
Militära insatser i urban miljö kommer troligen att öka alltmer. Detta kräver soldater till fots eftersom dessa lättare kan förflytta sig via och mellan byggnader. Varje deltagande soldat kommer att behöva egen radioutrustning. Då stadsmiljö är ett relativt outforskat område vad gäller militär radiokommunikation är det viktigt att öka förståelsen för radiovågors utbredning i stadsmiljö. Härtill har institutionen för Informationsöverföring på FOI köpt in programmet Radiowave Propagation Simulator (RPS).
Säkerheten i trådlösa nätverk
The number of wireless networks has increased rapidly among both home users and companies in just a few years. That has brought a lot of good things with it, for example the possibility to connect wireless equipment to the network or Internet from an arbitrary position within range of the accesspoint. But since the transmissions take place through the air some new security risks appear. It?s difficult to restrict the signals to a specific space and thereby a lot easier for unauthorized to eavesdrop or disturb the signals compared to a traditional wired network.
Politecast : ett nytt kommunikationsprimitiv för trådlösa sensornätverk
Wireless sensor networks have the potential for becoming a huge market. Ericsson predicts 50 billion devices interconnected to the Internet by the year 2020. Before that, the devices must be made to be able to withstand years of usage without having to change power source as that would be too costly. These devices are typically small, inexpensive and severally resource constrained. Communication is mainly wireless, and the wireless transceiver on the node is typically the most power hungry component.
Byggnadens andra skepnad : En anpassning för att möta samhällets behov och krav
Population growth leads to an increased need for new buildings, both residential and commercial. The regulations of structural design also changes with time. From a sustainable community perspective it may be profitable if existing buildings, that no longer performs their original function, are reconditioned. Knowledge and understanding of the surroundings of the residence must be available. Regulations regarding accessibility to all has increased.
Industrilandskapet i Norrköping : Kunskaper, värden och väg till bevarande
This study focuses the development on the protection of landscapes with old industries and how it nowadays is appreciated by the inhabitants. The overall aim of this study is to increase the knowledge about how the so called industrial landscape in Norrköping became a cultural heritage that the citizens want to protect. The study also aims to investigate the citizens´ knowledge about the industrial landscape in Norrköping, and what value they think that the place possesses. Data was collected by an information research and six qualitative interviews. The interviews where analysed by qualitative methods techniques.
Fasta driftställen på internet : Ett koncept på (juridiskt) lös grund?
The purpose of this essay is to examine and compare the news covering of Swedens three biggest cities (the metropolitan areas) and their surrounding areas with the covering of the rest of the country (the provincial areas) in two daily national newspapers, Aftonbladet and Dagens Nyheter. The aim has been to answer the following questions:- What amount of the news coverage in Aftonbladet and Dagens Nyheter concern the metropolitan areas compared to the provincial areas, and how do these two newspapers differ in the news covering of these areas?- Is there a difference in the news articles size and content, depending on weather they concern the metropolitan or the provincial areas?- How has the balance between news concerning metropolitan and provincial areas changed over the recent 20 years?The theories used in this study are News values, the media commercialization and Popular Journalism, and The Agenda Setting Theory. The method that has been used is a Quantitative Content Analysis.Despite the essays hypothesis, that the news coverage in the two newspapers would be dominated by material from the metropolitan areas, the result showed that a majority of the examined articles concern the provincial areas. It also showed that Aftonbladet has a bigger percentage of provincial news than Dagens Nyheter.
Mikroproduktion av solel i flerfamiljshus : Lönsamhetsanalys genom simulering av solcellsanläggningar och explorativ kundundersökning
This thesis is commissioned by the Swedish electricity trading company GodEl with the purpose of evaluate solar electricity in multi-family buildings in the Stockholm region. The prices of solar panels have dropped recently due to the advances in technology, but the installation rate in Sweden remains low. It is therefore interesting to study the profitability of solar electricity today, and if it is profitable enough to install based on profitability alone and not simply due to environmental considerations. Therefore this thesis first studies the profitability of solar panels based on a simulation of electricity production and consumption for multi-family buildings this region. The study concludes that solar electricity can be profitable in the Stockholm region under certain conditions; all of which have to be favourable for profitable solar electricity.The thesis also studies the opinion of the company's costumers concerning solar electricity.
A diagnostic method for oral cancer screening in a Brazilian population. A pilot study.
Inledning:
Oral cancer är ett allvarligt tillstånd med hög dödlighet, särskilt vid sen diagnostisering. Brasilien är ett av de länder i världen som har högst prevalens och dödlighet i oral cancer och det är den femte vanligaste cancerformen I landet. Ett hjälpmedel för tidig diagnostisering är önskvärd.
Syfte:
Att utvärdera skillnaden i diagnostisk tillförlitlighet mellan konventionell oral undersökning och användning av multispektralt ljus (Identafi®) som en metod för tidig upptäckt av potentiellt maligna och maligna lesioner i munslemhinnan i en brasiliansk befolkning.
Material och metod:
Screening av en befolkning med förhöjd risk för att utveckla oral cancer i Goiânia, Goiás, Brasilien, för att upptäcka potentiellt maligna (PML) eller maligna lesioner (ML). Patienter med misstänkta PML eller ML upptäckta under screeningen undersöktes med multispektralt ljus (Identafi®). Tre oberoende observatörer genomförde bedömning med Identafi® och slutgiltig beslut avseende PML/ML togs i konsensus.
Utvärdering av simulationsträning - finns det evidens för lärande? : En litteraturstudie
På uppdrag av Kliniskt Tränings- och Simulerinscentrum (KTC) kom författarna till denna studie i kontakt med ämnet simulationsträning. Simulationsträning introducerades under 50-talet i den medicinska världen. Sedan dess har det gjorts många framsteg och förbättringar på området, i takt med att kraven ökar på sjuksköterskans arbetsuppgifter. Syftet med den här studien var att studera effekter av simulationsträning. Studien baseras på tio vetenskapliga artiklar vilka behandlar simulationsträning och dess effekter.