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162 Uppsatser om Neighbor Unreachability Detection - Sida 3 av 11
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.
Validation of a tetraplex assay for detection of antibodies in poultry serum using Luminex 200 platform.
Background: As a part of a national health control program, Statens VeterinärmedicinskaAnstalt performs diagnostics to screen flocks for certain pathogens causing high mortality,morbidity and/or serious economical losses. There are several viruses in the programincluding IBDV (infectious bursal disease virus), IBV (infectious bronchitis virus) and NDV(Newcastle disease virus). Method: 96 serum samples were collected from different poultryflocks in Sweden and analyzed by ELISA, which are currently used in the health controlprogram as well as by a commercial prototype of a multiplex immunoassay manufactured byLuminex Corp., which is currently under evaluation at the United States Department ofAgriculture USDA. This 4-plex assay detects antibodies for the three above-mentionedviruses as well as antibodies of avian reovirus. In the context of this study the ELISAs run inroutine diagnostics as well as a REO ELISA were used as the standard for comparison.Result: The antibody concentration in serum from vaccinated chickens was high while theantibody concentration level in serum from not vaccinated chickens was low.
Identifikation av icke-representativa svar i fra?geunderso?kningar genom detektion av multivariata avvikare
To United Minds, large-scale surveys are an important offering to clients, not least the public opinion poll Va?ljarbarometern. A risk associated with surveys is satisficing ? sub-optimal response behaviour impairing the possibility of correctly describing the sampled population through its results. The purpose of this study is to ? through the use of multivariate outlier detection methods - identify those observations assumed to be non-representative of the population.
En explorativ studie om människors förmåga att uppfatta bilförares mentala arbetsbelastning
Under de senaste åren har olika former av kognitiv distraktion, till exempel att tala i mobiltelefon med handsfree, relaterats till en betydande mängd olyckor i trafiken. Av den anledning finns det ett stort intresse i att ta fram olika tekniska system för att upptäcka förare som är distraherade. Målet med denna studie var att ta ett steg tillbaka och undersöka människors förmåga och metoder för att avgöra distraktion hos andra. Då det saknas tidigare forskning är upplägget en explorativ förstudie bestående av två delar. Under den första delen samlades material in på distraherade bilförare i simulerad förarmiljö.
Quantitative thermal perception thresholds, comparison between methods
Skin temperature is detected through signals in unmyelinated C-fibers and thin myelinated A?-fibers in the peripheral and central nervous system. Disorders in thin nerve fibres are important and not rare but difficult to diagnose by the most common neurophysiological methods. In this pilot study different methods for quantitative sensory testing, QST, were compared to give some ideas about which method could be the most efficient to use in order to point out injuries of the sensory system in clinical practice. The comparison was made between Békésy (separate warmand cold thresholds) and Marstock test (combined warm and cold thresholds).
Development of real-time RT-PCR for the detection of human sapovirus in foods
Food-poisoning is a major health problem and an estimated half a million Swedes are food-poisoned annually, with acute gastroenteritis as a consequence. One of the major causes of contaminated foods is related to food- and waterborne viruses. To be able to trace back the source of contaminant, the method of detecting viruses must be specific and sensitive. No standardized method for detecting foods for sapovirus exists today.
The aim of the work described in this bachelor thesis is to implement and opti-mize a real-time RT-PCR method for the detection of all genogroups of human sapovirus in foods.
Detection of interesting areas in images by using convexity and rotational symmetries
There are several methods avaliable to find areas of interest, but most fail at detecting such areas in cluttered scenes. In this paper two methods will be presented and tested in a qualitative perspective. The first is the darg operator, which is used to detect three dimensional convex or concave objects by calculating the derivative of the argument of the gradient in one direction of four rotated versions. The four versions are thereafter added together in their original orientation. A multi scale version is recommended to avoid the problem that the standard deviation of the Gaussians, combined with the derivatives, controls the scale of the object, which is detected.
Optimization of Western Blot for detection of cellspecific localization of DNA binding protein fromstarved cells (Dps) in Nostoc punctiforme
Cyanobacteria belong to the oldest organisms of our planet. They use photosynthesis to produce ATP and gain biomass from carbon dioxide. The cyanobacteria Nostoc punctiforme is a filamentous bacterium that consists of two different types of cells, vegetative cells and heterocysts. The type of cell it differentiates into depends on the media they grow in. In an ammonium-rich medium, the N.punctiforme consists of vegetative cells that differentiate into heterocysts when in the medium is changed to a low-concentration ammonium medium.
Kvantitativ RT-PCR-analys för detektion av pigmentrelaterade transkript i hårrötter från hund :
Malignant melanoma represents 4-7% of all canine neoplasms and they are the most common malignant tumors of the oral cavity and digits. These tumors are often aggressive and metastasize quickly. To date there is no effective treatment and survival times are short. Most dogs are euthanized due to complications caused by metastases. Melanin pigment is a hallmark of melanomas and is usually present in large amounts in these tumors.
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.
Övergången till IPv6: Säkerhetsrisker
Den 21 januari 2011 delades de sista tillgängliga blocken av IPv4-adresser ut. Detta gör att dess efterträdare IPv6 är aktuellare än någonsin, då det snart inte finns några adresser kvar. IPv6 för med sig mer inbyggd säkerhet, men också nya säkerhetsrisker. Detta arbete undersöker vilka säkerhetsrisker gällande tillgänglighet som finns vid en övergång från IPv4 till IPv6 och vilken medvetenhet systemadministratörer har om dessa. Resultaten tyder på att det finns en mängd olika säkerhetsrisker vid övergången till IPv6.
Induktiv provning av ferritiskt rostfritt stå
The report examines the factors which may be a contributing cause to the problems that are present when ferritic stainless steel are eddy current tested in a warm condition. The work is carried out at Fagersta Stainless AB in Fagersta which manufactures stainless steel wire. In the rolling mill there is an eddy current equipment for detection of surface defects on the wire. The ferritic stainless steels cause a noise when testing and this noise complicates the detection of defects.Because of this, a study was made of how the noise related to factors such as steel grade, temperature, size and velocity. By observing the signal and with the possibilities to change the equipment settings the capability to let a signal filter reduce the noise level were evaluated.
Optimization of immunoassay parameters in multiplex in the high throughput protein detection technique Proximity Extension Assay
The ability to detect protein-based biomarkers, which are linked to different diseases like colorectal cancer, is very important as a diagnostic tool. Usually complex biological samples like blood are studied which will contribute to different technical issues when performing an assay. The aim with the project is to optimize and develop the high throughput protein detection technique Proximity Extension Assay, PEA, into a 96-plex panel, in hopes of discovering an expression profile for colorectal cancer. PEA was developed by Olink Bioscience and allows specific proteins in a sample to be quantitatively transformed into nucleic acid sequences that are subsequently detected and quantified with real-time PCR. Two proximity probes containing oligonucleotide sequences bind pairwise to target protein and when brought in proximity, a DNA polymerase will extend a hybridization arm from one probe over to the second forming a double-stranded DNA sequence that can serve as a template in real-time PCR.
Initial evaluation of the Meritas Troponin I test for measurement of equine cardiac troponin I
Cardiac troponin I (cTnI) is considered a specific and a sensitive biomarker of cardiac disease, and due to a high inter-species sequence homology; human cTnI assays can often be used in veterinary medicine. The main aim of this study was to perform an initial evaluation of a human cTnI test, the Meritas Troponin I test, for measurement of equine plasma cTnI, in order to investigate whether the test could be a possible subject for a more comprehensive validation. The hypothesis was that the test could measure equine cTnI, as there is a good homology between equine cTnI and human cTnI.
The evaluation included a dilution parallelism, an intra-assay precision study and measurement of plasma cTnI healthy horses. In the dilution parallelism and the intra-assay precision study, equine plasma with previously established high cTnI concentration, according to another cTnI assay, was used. In addition, cTnI concentration was measured in plasma, collected from 19 horses, without signs of disease at physical and ECG examinations.
The obtained curve in the dilution parallelism was linear, indicating that the Meritas Troponin I test can be used to measure different concentrations of equine cTnI in plasma.