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154 Uppsatser om Detection - Sida 2 av 11

IPv6 - Gatewayredundans : Snabbt nog?

IPv6 har, till skillnad från tidigare versioner av protokollet, inbyggt stöd för redundans hos gatewayenheter. Vid nyttjande av ett flertal gatewayenheter kan det, med hjälp av Neighbor Unreachability Detection, ske automatisk övergång till en ny gatewayenhet utifall att den aktiva skulle gå ur funktion. Innan IPv6 har man varit tvungen att förlita sig på externa lösningar för att uppnå denna redundans. Den huvudsakliga fråga som ställs i rapporten är om det inbyggda stödet för gatewayredundans i IPv6 är tillräckligt snabbt för att kunna nyttjas självständigt, utan att förlita sig på externa lösningar. För att kunna ta fram ett värde om vad som var ?tillräckligt snabbt? har vi, genom att läsa tidigare forskning om användares upplevelse av fördröjningar, kommit fram till att en fördröjning ej får överstiga tio sekunder.

Algoritmer för objektdetektering i SAR och IR-bilder

The first part of the thesis consists of a brief introduction to the general principles of target Detection and the sensor-systems used. In the following part there is a theoretical description of the algorithms this thesis focuses on. The Detection algorithms described in this paper are called Cell Average, Ordered Statistics, 2parameter and Gammadetector. Two different discriminators called Extended Fractal Features and Quadratic Gamma Discriminator are also described. The algorithms are tested on three different types of data, simulated SAR-pictures, authentic SAR-targets and IR-pictures.

Optimering av informationsinsamlingvid prototyptillverkning

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.

Validering av metoder för analys av Cu, Fe och Na i processvatten med AAS-grafitugn

Södra Cell Mörrum is one of the five paper pulp plants that are included in Södra Cell, and the paper pulp that is produced here is not only sold to Swedish paper mills. Most of the paper pulp is exported to different countries in Europe. In the manufacturing process the plant needs different kind of process water and there are guideline values for how much copper, iron and sodium this water is allowed to contain. Analyzes of this water is in the current situation done with an atomic absorption spectrometric instrument (AAS-instrument) with a flame. Measurements done with flame-AAS of samples that have concentrations near the guideline values for copper, iron and sodium, are not reliable. The reason for not being reliable is that the quantitation limits of these metals are higher than the limit values.

Wildlife Detection Network

Traffic accidents where wild animals are involved represents between 60 and 80 percent of all reported accidents, depending on location in Sweden. In a country like Sweden, with a lot of forest, there is always risk of a collision with a wild animal. Imagine if you, as a road user, had the possibility to receive warnings when the risk of an accident according to statistics is extra high.Wildlife Detection Network is a wildlife warning system with an information service, which makes the whole concept unique. When an animal is approaching the road, it is registered by sensors, and warning lights along the road are lit to inform drivers of the potential danger. In conclusion, this is a direct warning to all drivers on the road where the system is placed.When an animal is registered by the sensors, information containing time, date, weather circumstances and coordinates are sent to a database.

Police Science - expansionen av ett kunskapsfält : En studie om vetenskapligt gränsdragningsarbete i 1930-talets Chicago

In 1929, the Scientific Crime Detection Laboratory was established in Chicago?the first of its kind in the United States. The purpose was to engage in practical use of scientific methods in the Detection of crime. In 1930, the institute published its own periodical called The American Journal of Police Science. Applying the theory of boundary-work, this essay analyses how the novelty institute argued its legitimacy as a scientific establishment through the expansion of Police Science as a collective field of knowledge.

Implementering av Constant Fraction Detection vid avståndsmätning

This thesis is performed at Saab Bofors Dynamics in Karlskoga and investigates a technique for ranging with laser pulses. The investigated technique is called Constant Fraction Detection (CFD). Described briefly, the received laser pulse is split into two equal parts, where one part is delayed half the pulse width and inverted. This signal is added to the original pulse. The resulting curve has the shape of a laying S and the Detection of the zero level is used to stop the time measurement.

detection and quantification of almond (Prunus dulcis) in food with ELISA

Reliable methods to analyze food for the presence of almond are important ? not only for those allergic to almond, but also for monitoring the compliance with labelling regulations (EG directive 2003/89). Until now the Swedish National Food Administration has used methods like rocket immunoelectrophoresis and real-time PCR to detect almond in food. These methods are, however, not sensitive enough for protecting the most sensitive individuals. Therefore, the performance of a commercial ELISA kit was tested with regard to specificity/cross reactivity and limit of Detection for almond both in solution and in different matrixes.The limit of quantitation was at least 3,1 ppm (mg/kg) in solution and similar concentrations were measured in bisquits and chocolate.

Metabolit- och hormonnivåer som tidiga markörer för fruktsamhet och produktionsstörningar hos mjölkkor

During the last decades the fertility of dairy cows has declined in the same rate as the milk yield has increased. This is a result of the negative genetic correlation between milk yield and fertility, failure to show estrous signs and metabolic problems in the cow. The purpose of this review was to investigate the function of metabolites and hormones as markers for disturbances in fertility, health and production in the dairy cow. There are several metabolites that are suggested to indicate the cow?s energy balance.

Improvement of positive strand assay used in detecting positive and negative RNA of hepatitis E virus

Background: Hepatitis E (HEV) is a small, non-enveloped virus that belongs to the viral genus Hepevirus. HEV is a positive sense single-stranded RNA virus and there is insufficient information regarding its replication. This is mainly because the virus has low capacity to grow in normally used cell cultures. Many specific strand assay Detection studies have been done in order to understand more about HEV replication. Unfortunately, these assays have the disadvantage of giving false positive results.Aim: The aim of this project was to improve the positive strand assay to increase specificity and eliminate false positivity which is due to high sensitivity of the polymerase chain reaction (PCR).

Feldetektering för diagnos med differentialgeometriska metoder -en implementering i Mathematica

Diagnosis means Detection and isolation of faults. A model based diagnosis system is built on a mathematical model of the system. The difficulty when constructing the diagnosis system depends om how the model is formulated. In this report, a method is described that rewrites the model on such a form that the construction of the diagnosis algoritm is easy. The model is transformed by two state space transformations and the result will be a system on state space form where one part of the system becomes easy to supervise.

Informationssäkerhet inom grafiska företag

The study shows the current need for security solutions concerning work with information in different areas.Investigations will show important solutions for printers? needs to meet the increasingly harder demands forfast and safe digital communications. Important factors to be analyzed in the investigations are: access todifferent types of information, workers authority of information, access to the data base register internallyand externally, production solutions for an effective fault Detection and data base solutions fororders and distribution.Planned and unplanned stops result in a standard of value in interruptions. Internal data bases areprotected by so-called ?Fire Walls?, ?Watch Dogs? and Virtual Private Networks.

Side Blind Spot Detection : Sensortekniker och hårdvara

Denna rapport är resultatet av ett examensarbete, på 20 högskolepoäng, som har utförts på Scania CV AB, Tekniskt centrum, Södertälje. Examensarbetet behandlar Side Blind Spot Detection och har resulterat i ett prototypsystem som detekterar objekt i döda vinklarna på sidorna av en lastbil. Systemet är ett aktivt säkerhetssystem som syftar till att förhindra olyckor och ge ökad trafiksäkerhet på vägarna. Examensarbetet har varit tvådelat för att uppnå detta mål. Denna rapport behandlar främst val av sensorteknik för att upptäcka objekt i de döda vinklarna på sidan av en lastbil.

Detektering av krypterade filer

In contemporary encryption the vast amount of text subject to cracking has brought about the demand for methods distinguish files more likely to be encrypted. The encryption software Truecrypt can encrypt files that are not possible to identify with a file signature. To solve the Detection problem, an algorithm sensitive to the absence of structure in the very code of files was developed. The program was written in the programming language EnScript which is built into the forensic software suite EnCase. The essential part of the algorithm therefore deployes the statistic of a chi-square test for deviance from a uniform distribution to distinguish files with contents that appear to be random.

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.

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