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23 Uppsatser om Antenna arrays - Sida 2 av 2

Automatiskt Nödstopp

In today?s industry it is starting to get more and more interesting with wireless systems and solutions for applications. To be able to reduce the amount of cables drawn to various machines which takes both space and an extra fee for every cable drawn. Some systems might require the user to use a handheld device that is directly connected by a cable which in some machines might be inelegant for the user.The goal with this bachelor thesis is to develop wireless monitoring of the machine operators position that is working with heavy industrial machinery. The thesis started out with researching different techniques for positioning a transmitter indoors, this was done in order to get a better understanding on how to go about.

SafeTool : Implementering av RFID-teknologi i maskiner för byggbranschen

Every year more than 6000 thefts, to a value of 1.5 billion SEK, are reportedwithin the Swedish building trade. Plus all the indirect costs of having theconstruction site standing still.SafeTool is a newly started company that will try to prevent this problem witha modern technology solution.The key to SafeTool?s solution is RFID ? Radio Frequency Identification ? andthe solution looks like this;All tools are stored in a container on the construction site. Every tool isequipped with a RFID-tag that uniquely identifies the tool. With antennas in thecontainer it is possible to detect when a tool is leaving the container and whenit comes back.

Development of Liquid Cooling for PCs

In recent years, existing solutions for cooling personal computer CPUs have been supplemented by a new product category, factory sealed water cooling loops. These systems, consisting of a water block with an integrated pump, a fan and a radiator, perform well compared to the air cooling solutions but are less effective than larger, custom-built water cooling systems.This project aims to explore the most important aspects of a factory sealed system and to identify possible cost-effective enhancements of the performance.The most significant differences between the different groups of water cooling loops are the block design and the pumping power. The performance of both categories is also largely dependent on the fan power, but increasing fan power has a large negative impact on the noise level.Both radiator size and fan model choice appear, in tests, to be relatively unimportant, presuming that the noise level is kept constant. The position and direction of the fan, however, has significant impact on both the temperature and the sound level.Water blocks can be designed in several different ways, both regarding the heatsink design and the flow direction. In simulation, flow with the inlet centered above the heatsink result in considerably lower pressure drop and slightly higher temperatures than flow through the block, for heatsinks with fin arrays.Creating a competitive product in this product segment certainly seems possible, as there are performance-increasing changes to be made that seemingly has little impact on the production cost.

MIMO kanalmodeler

The objective of this diploma work is to investigate a set of Multiple Input Multiple Output (MIMO) channel models compatible with the emerging IEEE 802.11n standard. This diploma work validates also advanced, innovative tools and wireless technologies that are necessary to facilitate wireless applications while maximizing spectral efficiency and throughput. MIMO channel models can be used to evaluate new Wireless Local Area Network (WLAN) proposals based on multiple antenna technologies. The purpose of this thesis is to investigate means of channel models and their implementation in different environments such as: Matlab, C++ and Advanced Design Systems (ADS). The investigation considers also a comparison between the channel models based on theoretical data and parameter setup to the channel models based on statistical characteristics obtained from measured data.

MPD-vågformer för helikopterradar

A helicopter based system equipped with a millimetre-wave fire control radar is studied for improvement of the detection probability for moving ground targets. The system is a pulse doppler radar that sends out the electromagnetic wave in repetitive pulses. The frequency in which radar sends this pulse is called Pulse Repetition Frequency (PRF). The velocity of the moving targets is measured by spectral analysis of the pulses received. With this sort of system some targets will not be possible to detect.

Fördröjning och bortfall av nätverkskorrektioner : osäkerhetskällor för nätverks-RTK

Network RTK is a real-time technique for accurate positioning with Global Navigation Satellite Systems (GNSS). The technology means the use of correction data from a network of GNSS receivers with known positions (reference stations) to reduce the uncertainty in position for the user´s GNSS receiver (rover). However, this requires that the correction data can be transferred seamlessly to the user in real time. Commonly the corrections are transferred via mobile phones. The Swedish National Land Survey operates a nationwide Network RTK service, where users can receive correction data via GSM or mobile Internet (GPRS).

Att skapa en tidningsapplikation till Dreampark AB:s IPTV-portal

Dreampark AB är ett IT-företag som bland annat håller på att utveckla ett Internet Protocoll TeleVission (IPTV) -system. IPTV innebär att TV-signalerna som mottas av TV-apparaten sänds över Internet. Det kan jämföras med kabel-TV där signalerna sänds via en kabel som är nergrävd i marken. I IPTV-systemet, som Dreampark byggt, har det byggts en interaktiv meny med många olika tjänster. Det går t.ex.

Inflytande av sommarväder på kornas val att vara på bete eller inne dagtid i en besättning, samt studier av andningsfrekvens och yttemperatur hos fokaldjur :

SAMMANFATTNING När man i tidigare undersökningar studerat betesgång för mjölkkor har klimatet på betet inte beaktats. En höglakterande ko producerar mycket värme som hon måste avge till sin omgivning för att kunna bibehålla sin kroppstemperatur. De sätt som djuret kan avge värme på är begränsade och påverkas av flera klimatfaktorer samt djurets genetiska och biologiska förutsättningar. Antalet dagar som registreringar gjordes under denna studie blev av flera olika anledningar få, 18 dagar. Klimatet utomhus under studien registrerat som globtemperatur varierade från 22,4 till 34,7ºC. Då djurskyddslagen skall främja djurens hälsa och djurets naturliga beteende fick en grupp 126 höglakterande kor möjlighet att välja uppehållsplats under tiden 26 juli till 11 augusti. 2004. Korna fördes ut på betet vid niotiden på förmiddagen och var därefter fria att gå in och ur stallet efter egen vilja tills de togs in för kvällsmjölkning omkring klockan tre påeftermiddagen.

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