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363 Uppsatser om Signal - Sida 12 av 25

Windbelt

Radio Frequency Identification, RFID, is a convenient way to enable contactless identification which does not require any physical nor optical contact. As with any radio-based communication the Signal can be intercepted, thus making the technology vulnerable to several kinds of attacks. Interception of communication is not the only threat. Since RFID tags might contain personal information or information that will grant the owner access to secure areas, skimming and spoofing attacks are also major threats against this technology. In this thesis report,  the perspective of an adversary is portrayed in an RFID-enabled environment by presenting where RFID is used and how it could be abused.

Analys av säkerheten av RFID i inpasseringssystem

Radio Frequency Identification, RFID, is a convenient way to enable contactless identification which does not require any physical nor optical contact. As with any radio-based communication the Signal can be intercepted, thus making the technology vulnerable to several kinds of attacks. Interception of communication is not the only threat. Since RFID tags might contain personal information or information that will grant the owner access to secure areas, skimming and spoofing attacks are also major threats against this technology. In this thesis report,  the perspective of an adversary is portrayed in an RFID-enabled environment by presenting where RFID is used and how it could be abused.

Passive acoustic diver detection

This report discusses a method to detect divers in harbour environments usingpassive acoustic detection. The goal was to achieve as high detection as possiblewithout having too high false alarm rate. A short execution time was also desirable.By using the characteristic of an inhalation a band-pass filter was applied to the Signalto improve the Signal to noise ratio. After the filtering an energy estimation of theSignal was made. This energy estimation was later used in a frequency analysis, whichcould tell us if there were enough energy in the frequencies that correspond to adivers breathing frequency.

Testprogram till hårdvara på en viktindikator

Radio Frequency Identification, RFID, is a convenient way to enable contactless identification which does not require any physical nor optical contact. As with any radio-based communication the Signal can be intercepted, thus making the technology vulnerable to several kinds of attacks. Interception of communication is not the only threat. Since RFID tags might contain personal information or information that will grant the owner access to secure areas, skimming and spoofing attacks are also major threats against this technology. In this thesis report,  the perspective of an adversary is portrayed in an RFID-enabled environment by presenting where RFID is used and how it could be abused.

Adaptiv temperaturreglering av bostadshus

The control of indoor temperature must be able to handle large time constants and both measureable disturbances like outdoor temperature, and non-measurable disturbances, like waste heat from appliances. Due to cheaper microcontrollers (small computers with designated tasks) with better performance, more advanced and computation-demanding methods for control can be used.In this thesis, Generalized Predictive Control (GPC) has been implemented and tested on a theoretically derived model of a house. GPC states that a model of the system is estimated in every sample, and the control is carried out simultaneously, based on predictions of the model. Disturbances like solar radiation can be estimated and used in the control as well. The control Signals are determined by quadratic programming, which makes it possible to consider conditions, for example limitations on the control Signals.GPC requires a number of parameters to be defined, like model order and control Signal penalty, but is relatively robust for variations in them.

Inlösen eller extrautdelning?: En studie av sambandet mellan valet av kapitalåterföringsmetod och värdeskapande för aktieägarna

This thesis studies the stock price reaction around 68 announcements of special dividends and share redemptions on the Swedish stock market between the years of 2003 and 2007. We show that for the Swedish private investor, the tax effect of a share redemption is lower than that of a special dividend. Moreover, a share redemption could be interpreted as a Signal of undervaluation. These two factors lead us to assume that the stock market would react more positively in connection to the announcement of a share redemption. We test this hypothesis through an analysis of the risk-adjusted abnormal return for the observations in the sample.

Priming av självrelevanta ord : Kan attributionsstil påverkas av omedvetna signaler?

Människor tenderar att attribuera framgångar till sig själva och misslyckanden till externa källor, fenomenet kallas för Self-serving bias. Hur individer attribuerar kan enligt forskning påverkas av bland annat graden av självkontroll samt självkänsla. Enligt forskning kan intentioner eller beteendemål aktiveras automatiskt och omedvetet av en utlösande Signal, så kallad priming, och därmed aktivt guida en persons självreglering. Denna studie har genom ett experiment, med 56 högskolestudenter, undersökt om priming av självkontroll och självförtroende kan påverka hur en individ attribuerar vid framgång och misslyckande. Resultatet visade ingen signifikant skillnad mellan priminggrupperna.

Mjukvaruverktyg för loggning och analys avindustriella processer

This report discusses developing a software log tool for analysis of industrial processes. The target was to develop software that can help electro Engineers for monitor and fault finding in industrial processes. The tool is called PLS (Process log server), and is developed in Visual Studio.NET Framework 2005. PLS works as a client with Beijer Electronics OPC Server. The program is able to read data from PLC (Programmable Logic Controller), trough the OPC Server.

Automatisk nivåreglering av strålkastare

To be allowed to sell Z-suspended vehicles with dipped beam Xenon or LED lighting, Scania have to develop automatic headlight level control. This master?s thesis aims to be the foundation to that development.The thesis consists of several parts; a market analysis of how competitors to Scania and the general vehicle industry solve this problem; several available principles for detecting the amount of control needed; the construction of a test station for sensors, a control unit and components connected controlled by the control unit; a further theoretical and practical development of one principle ? one rotational sensor connected between the chassis and the back drive axis; a state flow model programmed in Simulink that produces the control Signal for the headlight leveling from the sensor input.Lastly the thesis gives some recommendations to the further development and implementation of automatic headlight level control on Scania vehicles..

Testsystem för utredning av integrerad styrning för RC-helikopter

AbstractThis report is about the creation of a test system for development of a control system for a off the shelf RC-helicopter, which can be bought for about two thousand SEK. The test system consists of both electronics for controlling the helicopter and mechanical constrainer. The constrainer is used for mounting the helicopter so that it won´t crash.A circuit board including processor and sensors was manufactured. This was used for doing test of the different control algorithms. In this way were we able to analyze the quality of the sensors chosen, and what other sensors that could contribute to the control of the system.Basic helicopter control have been studied and presented in the report.

Magnetisk resonanstomografi

Denna rapport behandlar ämnet magnetisk resonanstomografi (MR), och kan sägas vara en orientering i ämnet, då många av de inom MR förekommande begreppen behandlas och systemets grundfunktioner tas upp. Det finns mycket litteratur i ämnet och för den intresserade finns alla möjligheter att fördjupa sig, referenslistan längst bak i detta arbete kan tjäna som boktips och guide till att komma igång med vidare studier. Arbetet tar upp den fysik som ligger till grund för magnetisk resonanstomografi och begrepp som protonspinn, nettomagnetisering och relaxationstider gås igenom. Dessutom görs en genomgång av hårdvaran i MR systemet och de olika varianter av system som finns, det vill säga permanenta-, resistiva- och supraledande magneter. Detta arbete fäster störst vikt vid de supraledande magnetsystemen eftersom de är de klart dominerande kliniskt.

Etnicitet och kön :  Påverkar grupptillhörighet bedömningar av korrekthet i centrala meningar från ett vittnesmål?

Syftet med denna studie var att studera möjligheten att bedöma korrekthet i vittnens utsagor beroende av deltagarnas grupptillhörighet. I studien ingick 120 deltagare som antingen fick se en film med vittnesmål från fyra vittnen med enstaka centrala meningar eller läsa en text med samma meningar. De viktigaste mätningarna i denna studie gjordes efter Signal detection theory (SDT). Resultaten visade att deltagarna inte skattade mycket över slumpnivå och ofta till och med under slumpnivå i sina bedömningar. I en hopslagning av betingelserna (text/film) visade analyserna att män generellt var signifikant sämre än kvinnorna på att bedöma vittnesmål, men att kvinnorna gör fler falska alarm än männen i bedömningen av textversionen.  De funna könsskillnaderna i hur vittnesmål bedöms diskuterades..

Förstudie för kvalitetssäkringav glidande förband vid Hissmoforsvattenkraftsstation : -Specifikt för aggregat G6 och G7

Jämtkraft AB which is a power production company in Sweden has bought two newhydro power units to their station in Hissmofors. The two new generators are using aconcept with sliding stator feet to handle the thermal expansion.The concept with sliding stator feet on hydro electric generators has not beenworking satisfactory on many hydro power stations in Sweden and has caused a lot ofcosts due to long downtimes.The new station in Hissmofors is very important for Jämtkraft AB, and therefore theywant to know how to make sure that the sliding stator feet are working as theyshould. According to theories and a simplified model of the generator the stator feetdisplacement should be around 1 -1,6 mm.The generators are delivered with a surveillance system that will measure thedisplacement of the sliding stator feet. The Signal from the system isn?t accessible forJämtkraft AB but it will alarm when the sliding stator feet are malfunctioning.To secure the function of the sliding feet a logger for the surveillance system or adifferent measurement system must be used; if both systems are used Jämtkraft cansecure the function of the surveillance system..

Ska pappa vara föräldraledig? : Ett naturligt experiment om pappamånadens påverkan på männens löneutveckling.

I denna uppsats undersöker jag om den procentuella löneutvecklingen för de män som fick barn precis efter det att den första pappamånaden infördes, januari 1995, var sämre än för de män som fick barn precis innan reformen genomfördes, december 1994. Med datamaterial från Statistiska centralbyrån, genomförs ett naturligt experiment. Den huvudsakliga slutsatsen då man jämför den procentuella löneutvecklingen av medellönerna är att även då de fäder som fick barn i januari 1995 tog ut mer föräldrapenning har inte deras löneutveckling påverkats. Löneutvecklingen för dessa fäder är densamma som för de fäder som fick barn i december 1994. Därmed finns det inget i denna uppsats som tyder på att om män tar ut en liten andel föräldraledighet sänder det en negativ Signal till arbetsgivaren som justerar lönen nedåt för mannen i fråga..

Basmobilen

Today?s cell phones include more and more functionality, it is no longer uncommon to be able to connect to the Internet or take photos with the cell phone. In this thesis the question is if the cell phone users are interested in this new functionality. Are there people who are interested in a cell phone that in this thesis is called ?Basmobilen? (the entry level phone), which include the following functions; phone call, SMS, phone book, calling lists, clock and the possibility to change the call Signal.

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