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282 Uppsatser om Feature extraction - Sida 2 av 19

Filtrering av e-post ? Binär klassifikation med naiv Bayesiansk teknik

In this thesis we compare how different strategies in choosing attribute values affects junk mail filtering. We used two different variants of a naïve Bayesian junk mail filter. The first variant classified an e-mail by comparing it to a feature vector containing all attribute values that were found in junk mails in the part of the e-mail collection we used for training the filter. The second variant compared an e-mail to a feature vector that consisted of the attributes that was found in ten or more junk mails in the part of the e-mail collection we used for training the filter. We used an e-mail collection that consisted of 300 e-mails, 210 of these were junk mails and 90 were legitimate e-mails.

Automatisk detektering av diken i LiDAR-data

Den här rapporten har utrett möjligheten att automatiskt identifiera diken frånflygburet insamlat LiDAR-data. Den metod för identifiering som har valts harförst skapat en höjdbild från LiDAR-data. Därefter har den tagit fram kandidatertill diken genom att vektorisera resultatet från en linjedetektering. Egenskaper-na för dikeskandidaterna har sedan beräknats genom en analys av höjdprofilerför varje enskild kandidat, där höjdprofilerna skapats utifrån ursprungliga data.Genom att filtrera kandidaterna efter deras egenskaper kan dikeskartor med an-vändarspecificerade mått på diken presenteras i ett vektorformat som underlättarvidare användning. Rapporten beskriver hur algoritmen har implementerats ochpresenterar också exempel på resultat.

Evaluation of preanalytic methods in order to shorten the processing time before identification of fungal microorganisms by the MALDI-TOF MS

Identification of fungi is based on macroscopic observations of morphology and microscopic characteristics. These conventional methods are time-consuming and requires expert knowledge. For the past years Matrix-assisted laser desorption ionization-time of flight mass spectrometry has been used for routine bacterial identification in clinical laboratories but not yet in the same extension for fungi. In this study three preanalytic preparation methods for fungi were evaluated in order to shorten the processing time in routine laboratory performance.Clinically relevant strains (n=18) of molds and dermatophytes were cultivated on agar plates and prepared according to the different preparation methods for protein extraction. Each strain was analyzed in quadruplicate by the MALDI Biotyper and the database Filamentous Fungi Library 1.0.The results showed that the genus and species identification rates of the least time-consuming direct extraction method were 33% and 11% respectively.

Media and the priming of stereotypes: Direct effect of news articles racial stereotypes on individuals judgements of people of foreign extraction.

The present research examined both automatic and controlled processes in newpapers ability of priming racial stereotypes via the portrayals of people of foreign extraction. The automatic process were examined through articles which; a) involved an illegal act or b) the act was not illegal but morally questionable. Swedish-born subject?s explicit opinions against foreign people were also measured through ?The Modern Racial Prejudice Scale?. In the experiment participants read four different articles which included; Swedish person/noncrime, foreign person/noncrime, Swedish person/crime and foreign person/crime.

Fördelar och nackdelar med utematematik : Lärares, föräldrars och elevers inställning till arbetsformen

Aligning parallell terms in a parallell corpus can be done by aligning all words and phrases in the corpus and then performing term extraction on the aligned set of word pairs. Alternatively, term extraction in the source and target text can be made separately and then the resulting term candidates can be aligned, forming aligned parallell terms. This thesis describes an implementation of a word aligner that is applied on extracted term candidates in both the source and the target texts. The term aligner uses statistical measures, the tool Giza++ and heuristics in the search for alignments. The evaluation reveals that the best results are obtained when the term alignment relies heavily on the Giza++ tool and Levenshtein heuristic..

Implementation och utvärdering av termlänkare i Java

Aligning parallell terms in a parallell corpus can be done by aligning all words and phrases in the corpus and then performing term extraction on the aligned set of word pairs. Alternatively, term extraction in the source and target text can be made separately and then the resulting term candidates can be aligned, forming aligned parallell terms. This thesis describes an implementation of a word aligner that is applied on extracted term candidates in both the source and the target texts. The term aligner uses statistical measures, the tool Giza++ and heuristics in the search for alignments. The evaluation reveals that the best results are obtained when the term alignment relies heavily on the Giza++ tool and Levenshtein heuristic..

Jämförande tidsstudie vid riskörning med kompakteringsskotare och traditionell ?lätt? modifierad skotare :

This report is a thesis work for a B.Sc. in Forestry exam at the School for Forest Engineers, SLU. The work was an assignment from Sydved Energy AB. The aim of the work was to compare the operational productivity between two kinds of forwarders for extraction of harvesting residues, one forwarder with a special compression device and one ordinary, slightly modified forwarder. Two sites were studied for each forwarder. The study shows that the annual production was about 11,000 m3 higher for the traditional forwarder. The cost for the traditional forwarder was SEK 0.9 lower per m3.

Support Vector Machines for Classification applied to Facial Expression Analysis and Remote Sensing

The subject of this thesis is the application of Support Vector Machines on two totally different applications, facial expressions recognition and remote sensing.The basic idea of kernel algorithms is to transpose input data in a higher dimensional space, the feature space, in which linear operations on the data can be processed more easily. These operations in the feature space can be expressed in terms of input data thanks to the kernel functions. Support Vector Machines is a classifier using this kernel method by computing, in the feature space and on basis of examples of the different classes, hyperplanes that separate the classes. The hyperplanes in the feature space correspond to non linear surfaces in the input space.Concerning facial expressions, the aim is to train and test a classifier able to recognise, on basis of some pictures of faces, which emotion (among these six ones: anger, disgust, fear, joy, sad, and surprise) that is expressed by the person in the picture. In this application, each picture has to be seen has a point in an N-dimensional space where N is the number of pixels in the image.The second application is the detection of camouflage nets hidden in vegetation using a hyperspectral image taken by an aircraft.

Evaluation of Different Extraction- and Analysis Methods for Calprotectin in Feces

Background Calprotectin is a protein expressed in the cytoplasm inside the neutrophile granulocytes. During inflammatory bowel disease (IBD), the neutrophile granulocytes are involved in a complex interaction at the inflammatory area where they die and release their content into the intestinal lumen. Therefore, calprotectin in stool is a suitable marker for diagnosis and measurement of the disease-activity in patients with IBD. The most commonly used method to detect calprotectin in stool is ELISA, but the process of manual preparation of stool samples is time-consuming.Aim The objective of the study was to evaluate an extraction method that could replace manual preparation of fecal samples and to compare different methods for measuring Calprotectin in stool using two ELISA-methods from two manufacturers and one rapidtest.Methods For extraction of calprotectin from stool samples we used sample collector tubes from Epitope Diagnostics and fecal preparation kits from Roche. Two different ELISA-kits for measuring calprotectin concentration in stool were compared.

Utveckling av hygienfunktioner i diskmaskiner : Desinfektion med hjälp av UV-ljus och ozon

This thesis within the field of Integrated Product development at the Royal Insitute ofTechnology, performed at Primary Development Dishcare at AB Electrolux, is supposed to finda solution to enhance the hygiene inside an Electrolux dishwasher. The outcomes of this thesisare functional prototypes to evaluate the efficiency of disinfection by the use of Ultra VioletLight and Ozone.The thesis has followed Electrolux Primary Development process, with delivarables andcheckpoints.Ultra violett light with a wavelength of around 264 nm penetrates through the cell wall ofbacteria and micro organisms and causes a molecular rearrangement of the cells DNA. Thisprevent the bacteria from reproducing and it is considered dead. Commonly used UV-C lampstransmits the wavelength 254 nm which is very close to the optimum for germicidal action.A competitive brand have reacently launched a dishwasher claiming to achieve greaterdisinfection with an UV feature. This dishwasher was tested during the thesis and proven tohave a very low effect on the hygienic result.Two prototypes were devolped and tested for UV disinfection of dishware.

Tillvaratagande av GROT i skärgårdsnära miljö :

The main aim of this study was to investigate and compare different methods for the extraction of forest fuel from environments close to an archipelago. The study was based on relevant literature and published reports as well as personal communications. Forestry has traditionally been characterized by intense efforts to rationalize and mechanize the cutting technique used for timber and pulpwood. In line with the increasing importance of forestry, more concentrated efforts can be expected in the area of techniques and methods, especially for the above-mentioned product lines. In Sweden, forestry is of major importance and the Swedish economy and standard of living have mainly been created based on the revenues generated from it. Thus, it is vital that Swedish forests are harvested in an efficient and responsible manner. The demand for biofuel is growing and today accounts for 15% of total Swedish energy production, a share that will probably increase. This study is based on three research questions, which are described under the heading of Aim. The results reveal that the most profitable method for handling forest fuel is the traditional one, which is also the most commonly used method in southern Sweden, namely the stockpiling of logs in a clearing by means of forwarders followed by splintering at the place from where they will be distributed. Today, the high cost of barge transport required for the extraction of forest fuel in an archipelago environment renders such operations unprofitable.

Anpassad skötsel - exempel på hyggesfritt skogsbruk i Mellannorrland :

Total protection is often the option chosen when protecting forests with high environmental values. An alternative to total protection is application of management regimes that do not interrupt continuity of tree cover. This study focuses mainly on continuous cover forestry (CCF) in forest stands already protected. All objects are situated in the county of Jämtland in northwest Sweden. The purpose of the study was to attain a greater knowledge about CCF practices.

Development of a method for determination of pesticide residues in honey using liquid chromatography tandem mass spectrometry

Honey is a product that may contain pesticide residues due to contamination from bees pollinating various plants as well as elimination of vermin inside the hive. Different methods are needed for analysis of pesticides, since the term includes a wide range of different substances. National Food Administration lacks a validated method for determination and quantification of pesticides in honey using liquid chromatography tandem mass spectrometry, LC-MS/MS. The technique is especially important in analysis of polar and non-volatile pesticides, where gas chromatography is not functioning optimally. After investigating what pesticides could be found in honey produced in Sweden, a number of four pesticides suitable for analysis with LC-MS/MS was compiled; boscalid, impidacloprid, tau-fluvalinate and thiacloprid.

Methods for Locating Distinct Features in Fingerprint Images

With the advance of the modern information society, the importance of reliable identity authentication has increased dramatically. Using biometrics as a means for verifying the identity of a person increases both the security and the convenience of the systems. By using yourself to verify your identity such risks as lost keys and misplaced passwords are removed and by virtue of this, convenience is also increased. The most mature and well-developed biometric technique is fingerprint recognition. Fingerprints are unique for each individual and they do not change over time, which is very desirable in this application.

En av grabbarna : En studie av kvinnliga journalisters roll inom TV-sport journalistiken

Syftet med denna uppsats är att undersöka hur svenska dagstidningsredaktioner förhåller sig till featurejournalistik i dag och vilken betydelse feature har för papperstidningens överlevnad. Undersökningen är uppdelad i en kvantitativ och en kvalitativ del. Vi har lagt fokus på fyra tidningar ? Katrineholms-kuriren, Norrköpings tidningar, Sydsvenska dagbladet och Göteborgs-posten. Som kvantitativ metod har vi räknat antalet texter med featurekaraktär i respektive tidning under en vecka i november 2009.

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