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Elektrisk lastprognostisering för byggnader / Electrical load prediction for buildingsBojestig, John January 2019 (has links)
Om världen ska kunna ställa om till förnyelsebara energikällor krävs det nya och bättre tekniklösningar. En liten del av lösningen på balanseringsproblematiken på elnätet som icke-reglerbara energikällor som sol- och vindkraft står för kan vara att sköta en del av balanseringen lokalt i byggnader med hjälp av batterilager. För att kunna styra den balanseringen på ett optimalt sätt behöver styrningen ha prognoser för hur stor den elektriska lasten i byggnaden kommer vara framöver. Syftet med denna studie har varit att utföra en elektrisk lastprognostisering för en byggnad över ett dygn. Modellen som utförde elektrisk lastprognostisering för en byggnad har baserats på neurala nätverk. Istället för att ha ett neuralt nätverk som prognostiserar över hela dygnet har 24 olika neurala nätverk prognostiserat varsin timma. Varje neuralt nätverk har valts efter tester mellan ett flertal neurala nätverk med variationer i parametrar som har tagits fram med hjälp av en klusteralgoritm. Resultatet visade att modellen som tagits fram i studien prognostiserade den elektriska lasten i en byggnad över ett dygn med en felmarginal enligt mean average percentage error på 5.67%. Det gick även att se fördelar med att dela upp prognostiseringen i mindre delar och testa olika parametrar för varje timma som skulle prognostiseras. Med avseende på jämförelser med andra studier och att bostadshus är ett välkänt svårt prognostiseringsproblem bör resultatet anses som godkänt. Det mesta tyder på att prognostiseringsmodellen är tillräckligt bra för att kunna assistera en smart styrning av ett batteri i en byggnad med användbar information / If the world should be able to convert to renewable energy sources, new and better technical solutions is required. A small part of the solution to the balancing problem on the electricity grid, as non-controllable energy sources such as solar and wind power is highly responsible for, can be to handle part of the balancing locally in buildings using battery storage. In order to be able to control this balancing in the optimal way, the control system needs to have forecasts of how large the electric load in the building will be in the future. The aim of this study has been to carry out electrical load prediction for a building over one day. The model that carried out electrical load forecasting for a building has been based on neural networks. Instead of having one neural network that predicts the whole day, 24 different neural networks have been forecasting each hour. Each neural network has been selected after testing between several neural networks with variations in parameters that have been selected using a cluster algorithm. The result showed that the model developed in the study predicted the electric load in a building over one day with a mean average percentage error of 5.67%. It was also possible to see the advantages of dividing the prediction into smaller parts and testing different parameters for each hour that would be forecast. With regard to comparisons with other studies and that residential buildings are a well-known difficult forecasting problem, the result should be considered as acceptable. Most indications show that the forecasting model is good enough to be able to assist a smart control of a battery in a building with useful information.
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System Designs for Diabetic Foot Ulcer Image AssessmentWang, Lei 07 March 2016 (has links)
For individuals with type 2 diabetes, diabetic foot ulcers represent a significant health issue and the wound care cost is quite high. Currently, clinicians and nurses mainly base their wound assessment on visual examination of wound size and the status of the wound tissue. This method is potentially inaccurate for wound assessment and requires extra clinical workload. In view of the prevalence of smartphones with high resolution digital camera, assessing wound healing by analyzing of real-time images using the significant computational power of today’s mobile devices is an attractive approach for managing foot ulcers. Alternatively, the smartphone may be used just for image capture and wireless transfer to a PC or laptop for image processing. To achieve accurate foot ulcer image assessment, we have developed and tested a novel automatic wound image analysis system which accomplishes the following conditions: 1) design of an easy-to-use image capture system which makes the image capture process comfortable for the patient and provides well-controlled image capture conditions; 2) synthesis of efficient and accurate algorithms for real-time wound boundary determination to measure the wound area size; 3) development of a quantitative method to assess the wound healing status based on a foot ulcer image sequence for a given patient and 4) design of a wound image assessment and management system that can be used both in the patient’s home and clinical environment in a tele-medicine fashion. In our work, the wound image is captured by the camera on the smartphone while the patient’s foot is held in place by an image capture box, which is specially design to aid patients in photographing ulcers occurring on the sole of their feet. The experimental results prove that our image capture system guarantees consistent illumination and a fixed distance between the foot and camera. These properties greatly reduce the complexity of the subsequent wound recognition and assessment. The most significant contribution of our work is the development of five different wound boundary determination approaches based on different computer vision algorithms. The first approach employs the level set algorithm to determine the wound boundary directly based on a manually set initial curve. The second and third approaches are the mean-shift segmentation based methods augmented by foot outline detection and analysis. These two approaches have been shown to be efficient to implement (especially on smartphones), prior-knowledge independent and able to provide reasonably accurate wound segmentation results given a set of well-tuned parameters. However, this method suffers from the lack of self-adaptivity due to the fact that it is not based on machine learning. Consequently, a two-stage Support Vector Machine (SVM) binary classifier based wound recognition approach is developed and implemented. This approach consists of three major steps 1) unsupervised super-pixel segmentation, 2) feature descriptor extraction for each super-pixel and 3) supervised classifier based wound boundary determination. The experimental results show that this approach provides promising performance (sensitivity: 73.3%, specificity: 95.6%) when dealing with foot ulcer images captured with our image capture box. In the third approach, we further relax the image capture constraints and generalize the application of our wound recognition system by applying the conditional random field (CRF) based model to solve the wound boundary determination. The key modules in this approach are the TextonBoost based potential learning at different scales and efficient CRF model inference to find the optimal labeling. Finally, the standard K-means clustering algorithm is applied to the determined wound area for color based wound tissue classification. To train the models used in the last two approaches, as well as to evaluate all three methods, we have collected about 100 wound images at the wound clinic in UMass Medical School by tracking 15 patients for a 2-year period, following an IRB approved protocol. The wound recognition results were compared with the ground truth generated by combining clinical labeling from three experienced clinicians. Specificity and sensitivity based measures indicate that the CRF based approach is the most reliable method despite its implementation complexity and computational demands. In addition, sample images of Moulage wound simulations are also used to increase the evaluation flexibility. The advantages and disadvantages of three approaches are described. Another important contribution of this work has been development of a healing score based mechanism for quantitative wound healing status assessment. The wound size and color composition measurements were converted to a score number ranging from 0-10, which indicates the healing trend based on comparisons of subsequent images to an initial foot ulcer image. By comparing the result of the healing score algorithm to the healing scores determined by experienced clinicians, we assess the clinical validity of our healing score algorithm. The level of agreement of our healing score with the three assessing clinicians was quantified by using the Kripendorff’s Alpha Coefficient (KAC). Finally, a collaborative wound image management system between the PC and smartphone was designed and successfully applied in the wound clinic for patients’ wound tracking purpose. This system is proven to be applicable in clinical environment and capable of providing interactive foot ulcer care in a telemedicine fashion.
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Analýza velkých dat v kontextu optimalizace mobilních sítí / Big data analytics in the context of mobile network performance optimizationKlus, Roman January 2019 (has links)
Tato práce se zabývá technologiemi velkých dat v kontextu měření parametrů sítě. Popisuje téma velkých dat a jejich využití, představuje základní parametry sítě, jejich měření a metody zhodnocení. Vyhodnocuje RTR NetTest aplikaci, testovací proceduru a měřené parametry. Byla vytvořena skupina nástrojů pro posouzení základních kvantitativních parametrů mobilní sítě na základě dat z databáze RTR. Rozbor denního efektu shrnuje časovou proměnlivost sítě. Chování v prostoru je posouzeno binováním a shlukovou analýzou, současně se srovnáním řízeného testování a crowdsourcingu.
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Application of machine learning for the clustering of wheat transcription factor proteins into families and sub-familiesSameer, Haleemath Sameena January 2022 (has links)
Wheat plays an important role in ensuring the global food security. Salinity of soil and water poses a major threat to its production and it affects both growth and development of wheat in a negative way. Wheat plants uses certain molecular mechanisms to adapt themselves under the salt stress.Transcription factor proteins are the proteins that control the response of the wheat towards abiotic stress like salinity.There are 56 transcription factor protein families in the wheat genome. However these transcription factor protein families are not classified into subfamilies.The main goal of this research study is to understand how machine learning algorithm can be used to identify and cluster the transcription factor proteins into sub families that can help in associating them with specific biological processes like salt stress. In this project K Mean Clustering method is used to cluster the WRKY transcription factor family into subfamilies. WRKY is identified and clustered into three distinct clusters. Cluster validation is performed using external validation and resulted in 90% validation score. This method can be applied to other transcription factor families also. This can ultimately be helpful in producing salt-tolerant varieties of the wheat that are resistant to abiotic stress like salinity and this can help to improve crop yield.
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Lost in Transcription : Evaluating Clustering and Few-Shot learningfor transcription of historical ciphersMagnifico, Giacomo January 2021 (has links)
Where there has been a steady development of Optical Character Recognition (OCR) techniques for printed documents, the instruments that provide good quality for hand-written manuscripts by Hand-written Text Recognition methods (HTR) and transcriptions are still some steps behind. With the main focus on historical ciphers (i.e. encrypted documents from the past with various types of symbol sets), this thesis examines the performance of two machine learning architectures developed within the DECRYPT project framework, a clustering based unsupervised algorithm and a semi-supervised few-shot deep-learning model. Both models are tested on seen and unseen scribes to evaluate the difference in performance and the shortcomings of the two architectures, with the secondary goal of determining the influences of the datasets on the performance. An in-depth analysis of the transcription results is performed with particular focus on the Alchemic and Zodiac symbol sets, with analysis of the model performance relative to character shape and size. The results show the promising performance of Few-Shot architectures when compared to Clustering algorithm, with a respective SER average of 0.336 (0.15 and 0.104 on seen data / 0.754 on unseen data) and 0.596 (0.638 and 0.350 on seen data / 0.8 on unseen data).
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