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Novos descritores de textura para localização e identificação de objetos em imagens usando Bag-of-Features / New texture descriptors for locating and identifying objects in images using Bag-of-FeaturesCarolina Toledo Ferraz 02 September 2016 (has links)
Descritores de características locais de imagens utilizados na representação de objetos têm se tornado muito populares nos últimos anos. Tais descritores têm a capacidade de caracterizar o conteúdo da imagem em dados compactos e discriminativos. As informações extraídas dos descritores são representadas por meio de vetores de características e são utilizados em várias aplicações, tais como reconhecimento de faces, cenas complexas e texturas. Neste trabalho foi explorada a análise e modelagem de descritores locais para caracterização de imagens invariantes a escala, rotação, iluminação e mudanças de ponto de vista. Esta tese apresenta três novos descritores locais que contribuem com o avanço das pesquisas atuais na área de visão computacional, desenvolvendo novos modelos para a caracterização de imagens e reconhecimento de imagens. A primeira contribuição desta tese é referente ao desenvolvimento de um descritor de imagens baseado no mapeamento das diferenças de nível de cinza, chamado Center-Symmetric Local Mapped Pattern (CS-LMP). O descritor proposto mostrou-se robusto a mudanças de escala, rotação, iluminação e mudanças parciais de ponto de vista, e foi comparado aos descritores Center-Symmetric Local Binary Pattern (CS-LBP) e Scale-Invariant Feature Transform (SIFT). A segunda contribuição é uma modificação do descritor CS-LMP, e foi denominada Modified Center-Symmetric Local Mapped Pattern (MCS-LMP). O descritor inclui o cálculo do pixel central na modelagem matemática, caracterizando melhor o conteúdo da mesma. O descritor proposto apresentou resultados superiores aos descritores CS-LMP, SIFT e LIOP na avaliação de reconhecimento de cenas complexas. A terceira contribuição é o desenvolvimento de um descritor de imagens chamado Mean-Local Mapped Pattern (M-LMP) que captura de modo mais fiel pequenas transições dos pixels na imagem, resultando em um número maior de \"matches\" corretos do que os descritores CS-LBP e SIFT. Além disso, foram realizados experimentos para classificação de objetos usando as base de imagens Caltech e Pascal VOC2006, apresentando melhores resultados comparando aos outros descritores em questão. Tal descritor foi proposto com a observação de que o descritor LBP pode gerar ruídos utilizando apenas a comparação dos vizinhos com o pixel central. O descritor M-LMP insere em sua modelagem matemática o cálculo da média dos pixels da vizinhança, com o objetivo de evitar ruídos e deixar as características mais robustas. Os descritores foram desenvolvidos de tal forma que seja possível uma redução de dimensionalidade de maneira simples e sem a necessidade de aplicação de técnicas como o PCA. Os resultados desse trabalho mostraram que os descritores propostos foram robustos na descrição das imagens, quantificando a similaridade entre as imagens por meio da abordagem Bag-of-Features (BoF), e com isso, apresentando resultados computacionais relevantes para a área de pesquisa. / Local feature descriptors used in objects representation have become very popular in recent years. Such descriptors have the ability to characterize the image content in compact and discriminative data. The information extracted from descriptors is represented by feature vectors and is used in various applications such as face recognition, complex scenes and textures. In this work we explored the analysis and modeling of local descriptors to characterize invariant scale images, rotation, changes in illumination and viewpoint. This thesis presents three new local descriptors that contribute to the current research advancement in computer vision area, developing new models for the characterization of images and image recognition. The first contribution is the development of a descriptor based on the mapping of gray-level-differences, called Center-Symmetric Local Mapped Pattern (CS-LMP). The proposed descriptor showed to be invariant to scale change, rotation, illumination and partial changes of viewpoint and compared to the descriptors Center-Symmetric Local Binary Pattern (CS-LBP) and Scale-Invariant Feature Trans- form (SIFT). The second contribution is a modification of the CS-LMP descriptor, which we call Modified Center-Symmetric Local Mapped Pattern (MCS-LMP). The descriptor includes the central pixel in mathematical modeling to better characterize the image content. The proposed descriptor presented superior results to CS-LMP , SIFT and LIOP descriptors in evaluating recognition of complex scenes. The third proposal includes the development of an image descriptor called Mean-Local Mapped Pattern (M-LMP) capturing more accurately small transitions of pixels in the image, resulting in a greater number of \"matches\" correct than CS-LBP and SIFT descriptors. In addition, experiments for classifying objects have been achieved by using the images based Caltech and Pascal VOC2006, presenting better results compared to other descriptors in question. This descriptor was proposed with the observation that the LBP descriptor can gene- rate noise using only the comparison of the neighbors to the central pixel. The M-LMP descriptor inserts in their mathematical modeling the averaging of the pixels of the neighborhood, in order to avoid noise and leave the more robust features. The results of this thesis showed that the proposed descriptors were robust in the description of the images, quantifying the similarity between images using the Bag-of-Features approach (BoF), and thus, presenting relevant computational results for the research area.
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A study of consumers' use of shopping bags at hypermarketsChen, Chun-kai 17 September 2004 (has links)
In order to cut down the overuse of plastic bags, the Taiwan government had implemented a restriction policy for the use of plastic shopping bags. Under this policy, hypermarkets, department stores, supermarkets and many other stores are prohibited from offering free plastic shopping bags. They can only sell them. Meanwhile, since their goods are cheap, various, and many hypermarkets have become a main shopping place and the kind of store where Taiwanese spend most of their money. This study was aimed to find out the variables affecting shoppers¡¦ bag-use behaviors¡Xwhich included bringing one¡¦s own bag and requesting bags from the salesperson¡Xat hypermarkets.
A bag-use model was proposed for these variables. It included six variables and was based on Hines, Hungerford and Tomera¡¦s (1986) model of responsible environmental behavior and Cheng¡¦s (2004) integrated model of environmental behavior. The variables were environmental concern, environmental responsibility, attitude toward the behavior, self-efficacy, response efficacy and situational factors. Results showed that the bag-use model could predict both kinds of environmental behaviors (Nagelkerke R2 = .68, .60). Self-efficacy was the main variable that determined whether shoppers would bring their bags to shopping, whereas situational variables determined whether shoppers would request bags from the salesperson. Implications of these results and suggestions for the authorities were discussed.
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Designens betydelse vid val av boxvin : En studie om konsumenters preferenser av designfaktorer på bag-in-box-vin. / The significance of design in the choice of box wine : A study on consumer preferences of design factors on bag-in-box wine.Dahlqvist, Sofia, Hedén, Marie January 2015 (has links)
På den svenska marknaden står bag-in-box-vin för över 50 procent av allt vin som säljs och Sverige är det land där bag-in-boxen fått starkast fäste i världen (Fremin, 2012). Det gör att bag-in-box-förpackningen är en stor och betydelsefull produkt för vintillverkare och att ha kunskap om säljande design är viktigt för grafiska formgivare samt övriga involverade företag. Den föreliggande studiens syfte var att undersöka vilka designfaktorer på bagin- box-förpackningar som påverkar konsumenternas val av vin i Sverige. Studien innefattade en visuell kartläggning som ämnade ge en överblick av utbudet på ett Systembolag. Detta genomfördes för att skapa en grund till den webbaserade enkätundersökningen som genomfördes under våren 2015. Resultaten visade att majoriteten av respondenterna valde vin baserat på förpackningens utseende och ansåg att de påverkades främst av färg, typsnitt, illustrationer och varumärken. Resultaten visade också att ju högre vinkunskap konsumenterna hade desto mindre påverkade designen deras val. Kvinnor och män hade generellt olika åsikter angående hur stor påverkan de olika designfaktorerna hade vid valet av bag-in-box-vin. Denna studie är endast ett avstamp till ett ämne som innefattar många påverkande faktorer. Det betyder att mer forskning krävs inom ämnet innan helt sanningsenliga resultat kan fastställas. / In the Swedish market the bag-in-box wine stands for over 50 percent of all wine that sells and Sweden is the country where the bag-in-box have the strongest hold in the world (Fremin, 2012). This makes bag-in-box packaging a major and significant product for winemakers. Therefore having knowledge about selling design is important for graphic designers and other involved companies. This study included a visual content analysis of the bag-in-box wine in a liquor store in Sweden in order to get an overview of the supply. With the results, a web-based survey was created and implemented in the spring of 2015. The results showed that the majority of the respondents chose the wine based on the appearance of the package and felt that they were mainly effected by the colour, font, illustrations and brand. Consumers with higher knowledge about wine were less effected by the design in their choice of wine. Women and men had generally different opinions about how much impact the different design factors had in the choice of bag-in-box wine. This study is only a starting point for a subject that includes many influencing factors. Further research is therefore needed before completely truthful results can be established.
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Escalonamento em grids computacionais: estudo de caso / Computational grid scheduling: a case studyValéria Quadros dos Reis 23 August 2005 (has links)
Esta dissertação tem por objetivo apresentar a proposta de uma política de escalonamento para grids computacionais. Essa política, intitulada Dynamic Max-Min2x, é orientada ao escalonamento de aplicações cujas tarefas não realizam comunicação entre si e visa a redução do tempo de resposta dessas aplicações através da utilização de atribuição dinâmica de tarefas e replicação das mesmas. Experimentos, feitos através de simulação, mostram que o tempo médio de resposta de aplicações utilizando-se a Dynamic Max-Min2x é inferior ao de outras políticas da literatura. Análises dos resultados desses experimentos apontam que esse tempo tende a ser mais atrativo principalmente quando as tarefas necessitam de muito processamento e quando há grande variação de carga no sistema, caracteristicas comuns em grids computacionais. Além disso, esta dissertação apresenta a implementação de um framework utilizando-se o Globus Toolkit, onde é possível a inserção de políticas de escalonamento para a submissão inteligente de tarefas em um grid computacional. / This Master thesis proposes a new grid scheduling policy called Dynamic Max-Min2x. This policy focuses on applications in which tasks do not communicate among themsenves and targets a response time reduction of these applications through the use of dynamic task distribution and replication techniques. Experiments, done using simulations, have shown that the response time related to Dynamic Max-Min2x is smaller than others policies found in literature. Analysis of the results have demonstrated that this time tends to become more attractive when tasks do not need much processing power and when there is a great load variation in the system, characteristics frequently found in grids. Furthermore, this thesis presents the implementation of a framework using Globus Toolkit, which makes possible the new scheduling policies insertion to provide an intelligent submission tasks in a computational grid system.
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Segmentação de iris utilizando bag of keypointsBrandão, Fábio Nascimento 10 August 2011 (has links)
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Previous issue date: 2011-08-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Biometrics is a study field which objective is the person recognition using physical and behavioural traits. These traits can be acquired by specific sensors or by cameras. The biometric systems are used for criminal identification, private areas access or document access. The iris recognition is reliable because the iris does not change in the lifetime and rarely it can be changed accidentally or intentionally since the iris is protected inside the human eye. This master thesis verify the possibility of usage the Bag of Keypoints technique for image parts classification, using SURF points inside these parts to use as seeds of the region growing technique and segment iris for a posterior recognition. Obtained results are of the order of 7% segmentation error and, although less than the state of the art (of the order of 3%), these results indicate the possibility of a more detailed verification of this technique, that can be easily adapted to other uses. / A biometria é uma área de estudo que tem como objetivo a identificação de pessoas através de características físicas e comportamentais. Estas características podem ser capturadas por sensores específicos, ou por câmeras. Os sistemas biométricos são utilizados, por exemplo, na identificação criminal, concessão de acesso à áreas privadas ou documentos. O reconhecimento de uma pessoa através da íris é confiável pois a íris não é alterada com o passar dos anos e são raros os casos de alteração acidental ou intencional uma vez que a íris está protegida dentro do olho humano. Esta dissertação explora a possibilidade do uso da técnica de Bag of Keypoints para classificação de partes de imagens, utiliza pontos SURF dentro destas partes para fazer crescimento de região e segmentar a íris para uma etapa posterior de identificação. Os resultados obtidos são da ordem de 7% de erro em termos de segmentação e, embora inferiores ao estado da arte (da ordem de 3%), indicam a possibilidade de uma exploração mais detalhada desta técnica, que pode ainda ser facilmente adaptada para outros usos.
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Sistemas neuromodulatórios: implicações fisiopatológicas / Neuromodulatory systems: patophysiologic implicationsDaniel Carneiro Carrettiero 17 April 2008 (has links)
Esta tese está organizada basicamente em quatro capítulos. O Capítulo I aborda as linhas gerais do presente trabalho, onde o sistema nervoso é caracterizado por um mosaico de redes neurais altamente organizadas, as quais promovem o controle e a manutenção das atividades vitais do corpo humano. Redes neurais geneticamente enfraquecidas podem predispor os indivíduos a desenvolver diversas patologias. Moléculas neuromodulatórias podem atuar fortalecendo estas redes, colaborando com o controle destas doenças. O objetivo geral deste trabalho é estudar a ação de duas moléculas neuromodulatórias endógenas, a adenosina e a co-chaperona BAG-2, sobre redes neurais específicas associadas à hipertensão essencial e à doença de Azheimer, contribuindo, assim, para o melhor entendimento, controle e prevenção destas patologias. O Capítulo II analisa os possíveis efeitos da adenosina sobre o controle neural da pressão arterial associado à patologia da hipertensão essencial, especificamente no núcleo do trato solitário (NTS) de ratos normotensos (WKY) e espontaneamente hipertensos (SHR). O primeiro artigo científico do presente trabalho (Capítulo II) demonstra que os receptores A1 de adenosina, além de estarem distribuídos de forma heterogênea dentro do NTS estão aumentados em ratos hipertensos quando comparados a ratos normotensos. Esta diferença parece preceder o desenvolvimento da hipertensão nestes animais. O segundo artigo científico (Capítulo II) descreve que os receptores A1 de adenosina são capazes de aumentar tanto o número como a afinidade dos receptores alfa2-adrenérgicos dentro de núcleos específicos do NTS. Esta ação modulatória é diferenciada em ratos hipertensos quando comparados a ratos normotensos, sugerindo uma importante alteração associada à hipertensão nestes animais. No terceiro artigo científico (Capítulo II) foi observado que a ação modulatória desencadeada pelos receptores A1 de adenosina sobre os receptores alfa2-adrenérgicos é dependente de fosfolipase C (PLC) e parece, também, ser diferenciada em ratos hipertensos quando comparados a ratos normotensos. Neste contexto, os resultados destes três trabalhos sugerem que a ativação dos receptores A1 de adenosina, em certas condições, poderia estar sensibilizando sistemas hipotensores dentro de subnúcleos específicos do NTS através dos receptores alfa2-adrenérgicos utilizando fosfolipase C como mensageiro intracelular. Este mecanismo poderia estar associado ao desenvolvimento da hipertensão essencial. O Capítulo III analisa os possíveis efeitos da co-chaperona BAG-2 sobre a proteína Tau. Agregados desta proteína são uma das características histopatológicas marcantes encontradas no encéfalo de pacientes com mal de Alzheimer. Foi demonstrado no presente trabalho um elegante mecanismo de degradação da proteína Tau fosforilada, uma isoforma considerada tóxica para o ambiente intracelular, através da co-chaperona BAG-2. Esta molécula tem a capacidade de inibir a atividade da chaperona CHIP, uma ligase de ubiquitina, impossibilitando a ubiquitinação e conseqüente degradação da proteína Tau pela via proteossomo ubiquitina-dependente. Foi observado que a proteína BAG-2 se associa fisicamente à proteína Tau, alterando a via de degradação ubiquitina-dependente para uma via não muito usual, ubiquitina-independente. A supressão da proteína BAG-2 leva a um aumento nos níveis de Tau em neurônios e sua superexpressão, uma diminuição. Foi observado, também, que a supressão da proteína BAG-2 pode levar a formação de agregados filamentosos, sugerindo que o efeito modulatório da proteína BAG-2 poderia estar relacionado com a remoção dos agregados intracelulares encontrados em pacientes com a doença de Alzheimer. Concluindo, BAG-2 poderia ser um importante alvo farmacológico para o tratamento desta patologia. Por fim, o capítulo IV encerra o presente trabalho com considerações finais importantes para o estudo, prevenção e controle de patologias multifatoriais como a hipertensão essencial e a doença de Alzheimer. Este estudo sugere que a adenosina e a co-chaperona BAG-2 poderiam ser alvos farmacológicos interessantes, que em conjunto com outras subtâncias, poderiam colaborar com o fortalecimento de redes neurais geneticamente enfraquecidas as quais predispõem os indivíduos a desenvolver tais patologias / Adenosine has been shown to modulate cardiovascular control at the levels of the nucleus tractus solitarii (NTS). This study shows the distribution and density of adenosine A1 receptor within the nucleus tractus solitarii (NTS) of Wistar Kyoto (WKY) and spontaneously hypertensive (SHR) rats from birth to adulthood (1,15,30 and 90 day-old). [3H]DPCPX was used as a ligant for in vitro autoradiography. The NTS shows heterogeneous distribution of adenosine A1 receptor in dorsomedial/dorsolateral, subpostremal and medial/intermediate subnuclei. Adenosine A1 receptor decrease in dorsomedial/dorsolateral according to rostral-caudal levels of 15, 30 and 90 day-old WKY and SHR rats. On the other hand, those receptors increase in subpostremal according to rostral-caudal levels of 30 and 90 days old WKY, and of 15, 30 and 90 day-old SHR. Furthermore, adenosine A1 receptors are increased in SHR as compared with WKY in dorsomedial/dorsolateral of 30 and 90 day-old rats and in subpostremal of 15, 30 and 90 day-old rats. Surprisingly, even in 15 days old SHR rats when hypertension is not yet apparent, [3H]DPCPX values were increased. Finally, adenosine A1 receptors increase from 1 to 30 day-old rats. Medial/intermediate did not show any changes in adenosine A1 receptors according rostral-caudal levels, age or strain. In summary, our result highlights the importance of A1 adenosine system regarding the neural control of blood pressure and the development of hypertension. Adenosine is known to modulate neuronal activity within the nucleus tractus solitarii (NTS). The modulatory effect of adenosine A1 receptors on alpha2-adrenoceptors was evaluated by quantitative radioautography within NTS subnuclei and by neuronal culture using normotensive (WKY) and hypertensive (SHR) rats. Radioautography was used to perform saturation experiment in order to obtain alpha2-adrenoceptors binding parameters (Bmax, KD) in the presence of 3 concentrations of CPA, an adenosine A1 receptor agonist. Neuronal culture was performed to confirm radioautoraphic results. [3H]RX821002, an alpha2-adrenoceptor antagonist, was used as a ligand for both approaches. Dorsomedial/dorsolateral subnucleus of WKY showed an increase in Bmax values (21%) induced by 10nM of CPA. However, subpostremal subnucleus showed a decrease in KD, values (24%) induced by 10nM of CPA. SHR showed the same pattern of changes within the same nuclei as compared with WKY; however the modulatory effect of CPA was induced by 1nM (increased Bmax, 17%; decreased KD, 26%). Cell culture confirmed these results, since 10-[5M and 10[-7M of CPA promoted an increase in [[3[H]RX821002 binding of WKY (53%) and SHR cells (48%), respectively. DPCPX, an adenosine A1 receptor antagonist, was used to block the modulatory effect promoted by CPA on alpha2-adrenoceptors binding. In conclusion, our study show, for the first time, a specific cross talk between adenosine A1 receptors increasing the binding of alpha2-adrenoceptors within the NTS, which might be important to understand the complex autonomic response induced by adenosine within the NTS. In addition, changes in the interaction between receptors might be relevant to understand the development of hypertension. Adenosine acts at many sites to modulate neuronal activity. The nucleus tractus solitarii (NTS) is known as a major brain site in cardiovascular control. Previous studies from our group have shown the adenosine A1 receptors increase the binding of alpha2-adrenoceptors within the NTS, suggesting the important role of adenosine in cardiovascular control. The aim of the present study is to evaluate the intracellular signaling responsible for such process using brainstem cell culture of Wistar (WR) rats by means of binding assay. 8 different concentration of CPA (10[-4 to 10[-11), an A1 adenosine agonist, were used to modulate [[3[H]RX821002 binding, an alpha2-adrenoceptor antagonist. DPCPX, an A1 adenosine antagonist, was used to block the modulatory effect of CPA on [3VH]RX821002 binding. 10-5M of CPA promote an increase in [[3H]RX821002 binding. The intracellular cascade involved in such modulatory process were evaluated using different intracellular signaling molecules inhibitors and two queletors [SQ22536, an adenylyl cyclase (AC) inhibitor, U-73122, an phospholipase C (PLC) inhibitor, Xestospongin C, an IP3 receptor inhibitor, Ro318220, an protein kinase calcium dependent (PKC), BAPTA, an intracellular calcium quelator, EGTA, an extracelular calcium quelator]. U-73122, Xestospongin C, Ro3326 and BAPTA were capable to inhibit the effect promoted by adenosine A1 receptor on [3H]RX821002 binding suggesting a modulation PLC, PKC, IP3 and Ca2+ dependent pathway. In conclusion, our study show, for the first time, that adenosine A1 receptor modulates the alpha2-adrenoceptors through a non-canonical phospholipase C dependent pathway. This result might be important to understand the adenosine role within the NTS in cardiovascular control. Tau inclusions are a prominent feature of many neurodegenerative diseases including Alzheimer\'s disease. Their presence suggests a failure in Tau degradation. The components of a Tau protein triage system consisting of CHIP/Hsc70 and other chaperones and co-chaperones have begun to emerge. However, the site of triage and the master regulatory elements have not yet been described. We have discovered an elegant mechanism of Tau degradation involving the co-chaperone BAG-2. BAG-2 binds to CHIP inhibiting its activity as an ubiquitine ligase preventing Tau ubiquitination. Tau bound to the microtubule and recruits BAG-2 where it clears Tau through an ubiquitin-independent proteossoma 20S dependent pathway. BAG-2 acts on Tau at precisely the site where it undergoes phosphorylation-dependent binding to the microtubule, more importantly, where it becomes vulnerable to misfolding and aggregation. Under conditions of proteasomal 26S blockade, Tau undergoes caspase mediated degradation. BAG-2 represents a critical point in clearing Tau that is prone to assembling into filaments. The suppression of BAG-2 leads to increased phosphorilated tau in neurons and its over-expression decreases phosphorilated tau.
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Studium dekompozice organické hmoty v půdě pomocí metody "čajových sáčků" / Study of decomposition of organic matter in soil using the method of "tea bags"Lišková, Kateřina January 2021 (has links)
The main aim of this master thesis was to introduce an optimal method which could be used for study of a decompostion of an organic matter in a soil. For this purpose was chosen based on a literaly review so-called tea bag method. With regard to the completeness of the work, a physico-chemical characterization of the soil environment and HS isolated from it was also performed. The degraded organic material was then further characterized using thermogravimetric analysis, elemental analysis, FT-IR spectroscopy, and the total content of water-extractable polyphenolic substances in the samples was also determined.
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Bagarna i den nya och gamla gymnasieskolan; Vägen till akademiska studierSerengil, Volkan January 2012 (has links)
Uppsatsen jämför (a) Restaurang- och livsmedelsprogrammet med inriktningen bageri och konditori (RL-BAG) och (b) Livsmedelsprogrammet mot bageri (LP-BAG) i relation till varandra och fortsatta akademiska studier. Det är motsvarande program från Gy11 respektive Gy2000.Frågeställningen fokuserar på skillnaden mellan RL-BAG och LP-BAG gällande behörigheten och tillgång till akademiska utbildningar vid två lärosäten.Syftet med uppsatsen är att ta reda på hur skillnaden ser ut för de aktuella gymnasieprogrammen. Att det finns en skillnad är redan konstaterad i bl.a. utformningen av den nya gymnasieskolan. En aspekt att se på uppsatsen är att den har en utvärderande funktion av den senaste gymnasieförordningens yrkesprogram (Gy11).Metoderna som används i undersökningen är i huvudsak kvantitativa (i skildringen/resultatet). Den mäter det bivariata förhållandet mellan kombinationer av behörighetsgivande gymnasiala kurser och programtillgången vid de aktuella lärosätena. I metoden används bl.a. SWOT för att definiera skillnaderna.Resultatet visar att det finns en skillnad i urvalet. Den grundläggande behörigheten för Gy11 är betydligt mer fördelaktig än den motsvarande nivån för Gy2000. Även om kärnämnena räknas med i LP-BAG. Däremot har LP-BAG tillgång till fler särskilt behörighetsgivande kurser som i olika kombinationer ger tillgång till fler utbildningar.
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Content based video retrieval via spatial-temporal information discoveryWang, Lei January 2013 (has links)
Content based video retrieval (CBVR) has been strongly motivated by a variety of realworld applications. Most state-of-the-art CBVR systems are built based on Bag-of-visual- Words (BovW) framework for visual resources representation and access. The framework, however, ignores spatial and temporal information contained in videos, which plays a fundamental role in unveiling semantic meanings. The information includes not only the spatial layout of visual content on a still frame (image), but also temporal changes across the sequential frames. Specially, spatially and temporally co-occurring visual words, which are extracted under the BovW framework, often tend to collaboratively represent objects, scenes, or events in the videos. The spatial and temporal information discovery would be useful to advance the CBVR technology. In this thesis, we propose to explore and analyse the spatial and temporal information from a new perspective: i) co-occurrence of the visual words is formulated as a correlation matrix, ii) spatial proximity and temporal coherence are analytically and empirically studied to re ne this correlation. Following this, a quantitative spatial and temporal correlation (STC) model is de ned. The STC discovered from either the query example (denoted by QC) or the data collection (denoted by DC) are assumed to determine speci- city of the visual words in the retrieval model, i:e: selected Words-Of-Interest are found more important for certain topics. Based on this hypothesis, we utilized the STC matrix to establish a novel visual content similarity measurement method and a query reformulation scheme for the retrieval model. Additionally, the STC also characterizes the context of the visual words, and accordingly a STC-Based context similarity measurement is proposed to detect the synonymous visual words. The method partially solves an inherent error of visual vocabulary under the BovW framework. Systematic experimental evaluations on public TRECVID and CC WEB VIDEO video collections demonstrate that the proposed methods based on the STC can substantially improve retrieval e ectiveness of the BovW framework. The retrieval model based on STC outperforms state-of-the-art CBVR methods on the data collections without storage and computational expense. Furthermore, the rebuilt visual vocabulary in this thesis is more compact and e ective. Above methods can be incorporated together for e ective and e cient CBVR system implementation. Based on the experimental results, it is concluded that the spatial-temporal correlation e ectively approximates the semantical correlation. This discovered correlation approximation can be utilized for both visual content representation and similarity measurement, which are key issues for CBVR technology development.
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Porovnání teplotního komfortu spacích pytlů dle normy EN 13 537 / Comparison of thermal comfort of sleeping bag according to EN 13 537Zabilanský, Jiří January 2011 (has links)
Title: Comparison of thermal comfort of sleeping bag according to EN 13537 Objectives: Objectives of the proposed work was to measure the temperature inside the sleeping bag during sleeping. Then to compare it with the information given on the labels of sleeping bags. Methods: This work has a experimental character. In our work we have used methods of experiment and field study. These methods were used to sample 7 sleeping bags from various manufacturers. Results: The information reported by manufacturers always do not correspond to real use of sleeping bags. EN 13537 has primarily orientation character. For the choice of sleeping bags we do not recommend to follow according only to the EN 13537. It is necessary to follow other parameters of sleeping bags (type and weight of insulation material and construction of chambers). Keywords: sleeping bag, EN 13537, thermal comfort
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