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183 Uppsatser om Multivariate detection - Sida 1 av 13

Use of dogs as odour detectors : a review of the scientific literture

A lot of various substances can be detected by dogs, as oestrous in cows, endangered species or non-biological substances like accelerants, narcotics, explosives, mines and pollutions and biological substances like identity (suspects), cancer (breast, lung, colorectal and bladder cancer), human remains (cadaver), bacteria and mould in buildings. The dogs are trained using non-scientific methods and not much research in detection training exists. This is a review of different types of dog detection, with focus on new research..

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.

Detektering av sprickor i vägytor med hjälp av Datorseende

This thesis describes new methods for automatic crack detection in pavements. Cracks in pavements can be used as an early indication for the need of reparation.Automatic crack detection is preferable compared to manual inventory; the repeatability can be better, the inventory can be done at a higher speed and can be done without interruption of the traffic.The automatic and semi-automatic crack detection systems that exist today use Image Analysis methods. There are today powerful methods available in the area of Computer Vision. These methods work in higher dimensions with greater complexity and generate measures of local signal properties, while Image Analyses methods for crack detection use morphological operations on binary images.Methods for digitalizing video data on VHS-cassettes and stitching images from nearby frames have been developed.Four methods for crack detection have been evaluated, and two of them have been used to form a crack detection and classification program implemented in the calculation program Matlab.One image set was used during the implementation and another image set was used for validation. The crack detection system did perform correct detection on 99.2 percent when analysing the images which were used during implementation.

Utvärdering av larmsystem för lageroptimering under trendvariation

Very often the interesting variables are explained by several underlying variables and in statistical analyses it is common to study the relationship between variables and groups of variables. Because of this multivariate analysis is commonly used in both science and industry. There are two problem with both univariate and multivariate analyses. One is when the variables are correlated. The other is when the number variables of exceeds the number of observations which makes the matrices algebra used in the analysis impossible to execute.

En jämförelse mellan några multivariata data-analysmetoder

Very often the interesting variables are explained by several underlying variables and in statistical analyses it is common to study the relationship between variables and groups of variables. Because of this multivariate analysis is commonly used in both science and industry. There are two problem with both univariate and multivariate analyses. One is when the variables are correlated. The other is when the number variables of exceeds the number of observations which makes the matrices algebra used in the analysis impossible to execute.

Objektdetektering i SAR- och IR-bilder

This report treats detection in IR-pictures taken from airplanes over the ground. The detection is divided in two parts. First there is a detection with filterkernels with the task to point on targets and objects that look like targets. The second part is a discriminator that demands more calculations and has the task to sort out the false alarms from the discriminator. Both the detector and the discriminator contain thresholds thats been trained from trainingsets of data.

Hur har det svenska handelsmönstret påverkats av ett medlemskap i EU?

Very often the interesting variables are explained by several underlying variables and in statistical analyses it is common to study the relationship between variables and groups of variables. Because of this multivariate analysis is commonly used in both science and industry. There are two problem with both univariate and multivariate analyses. One is when the variables are correlated. The other is when the number variables of exceeds the number of observations which makes the matrices algebra used in the analysis impossible to execute.

Heuristisk detektering av trojaner

The heuristic methods used by the anti-trojan application TrojanHunter have been evaluated. The evaluation shows that the heuristic scan engine of TrojanHunter has a very good detection ratio and that the detection ratio can be even further improved by implementing the suggested improvements, the most important of which is a white list to avoid misidentifying files that are known not to be trojans..

Mapping of clear-cuts in Swedish forest using satellite images acquired by the radar sensor ALOS PALSAR

This study presents results for observing forest changes in Sweden using multi-temporal L-band satellite data and is a part of the JAXA?s ALOS Kyoto and Carbon Initiative. An extensive dataset of images acquired by the Advanced Land Observing Satellite Phased Array type L-band Synthetic Aperture Radar (ALOS PALSAR) is investigated for clear-cut detection in boreal forests in northern Sweden (Lat. 64°14? N, Long.

Ett flervariabelt feldetekteringssystem för övervakning av bärlagertemperaturen i vattenkraftturbiner

The purpose of this thesis work was to develop an automatic fault detection system for surveillance of bearing temperature in hydropower turbines. The parameters used except the bearing temperature were cooling water temperature and cooling water flow. A simple static model based on data sampled every minute was developed to estimate the bearing temperature. Then a detector for detection of change in bearing temperature based on the CUSUM-algorithm was designed. Since the amount of data was very small the developed model was too uncertain to be used in a working system.The designed fault detection system showed to work well for the available data.

Registrering och avel för brunstvisningsförmåga hos mjölkkor

Dairy farmers using artificial insemination (AI) are dependent on effective oestrus detection. In Sweden, AI is used for a majority of all dairy cows and oestrus synchronisation with hormones is not allowed. There are reports of declining ability to express oestrus with higher levels of milk production. This makes oestrus detection more difficult. Several aids for oestrus detection have been developed, for instance pedometers and mounting detectors.

Prognostisering av räntabilitet på eget kapital - En jämförelsestudie av tre regressionsmodellers prognosförmåga applicerat på svenska data

A multivariate cross-sectional model is used in this thesis to proxy for expected earnings and to estimate return on equity for 214 companies over the period 2009-2013, using Swedish data. The model, which has never been tested on Swedish data before, is first confirmed to function as a forecasting model for expected return. Furthermore, the model is evaluated through a comparison with two univariate models based on the assumption that return on equity follows a mean reversion process. Forecast accuracy is calculated as the difference of estimated returns and actual returns. The results show that the univariate models' forecasts are superior to the multivariate model's..

Blinkbeteendebaserad trötthetsdetektering : metodutveckling och validering

Electrooculogram (EOG) data was used to develop, adjust and validate a method for drowsiness detection in drivers. The drowsiness detection was based on changes in blink behaviour and classification was made on a four graded scale. The purpose was to detect early signs of drowsiness in order to warn a driver. MATLAB was used for implementation. For adjustment and validatation, two different reference measures were used; driver reported ratings of drowsiness and an electroencephalogram (EEG) based scoring scale.

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.

Konfigurering av slutartider för ljusdetekterande mjukvara

This project measures the upper bound of exposure time for laser reflection detection in the software DotDetector. Via measurement of the exposure time for which distortion happens in a room lit with everyday light we conclude that the upper bound for exposure times are 100 milliseconds. This value does not change as long as the lighting in the room is the same. As future work this project proposes variable upper bounds depending on secondary lighting in the room. Also we propose automating the colour masking of the detection algorithm..

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