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重疊法應用於蛋白質質譜儀資料 / Overlap Technique on Protein Mass Spectrometry Data徐竣建, Hsu, Chun-Chien Unknown Date (has links)
癌症至今已連續蟬聯並高居國人十大死因之首,由於癌症初期病患接受適時治療的存活率較高,因此若能「早期發現,早期診斷,早期治療」則可降低死亡率。本文所引用的資料庫,是經由「表面強化雷射解吸電離飛行質譜技術」(SELDI-TOF-MS)所擷取建置的蛋白質質譜儀資料,包括兩筆高維度資料:一筆為攝護腺癌症,另一筆則為頭頸癌症。然而蛋白質質譜儀資料常因維度變數繁雜眾多,對於資料的存取容量及運算時間而言,往往造成相當沉重的負擔與不便;有鑑於此,本文之目的即在探討將高維度資料經由維度縮減後,找出分錯率最小化之分析方法,希冀提高癌症病例資料分類的準確性。
本研究分為實驗組及對照組兩部分,實驗組是以主成份分析(Principal Component Analysis,PCA)進行維度縮減,再利用支持向量機(Support Vector Machine,SVM)予以分類,最後藉由重疊法(Overlap)以期改善分類效果;對照組則是以支持向量機直接進行分類。分析結果顯示,重疊法對於攝護腺癌症具有顯著的改善效果,但對於頭頸癌症的改善效果卻不明顯。此外,本研究也探討關於蛋白質質譜儀資料之質量範圍,藉以確認專家學者所建議的質量範圍是否與分析結果相互一致。在攝護腺癌症中的原始資料,專家學者所建議的質量範圍以外,似乎仍隱藏著重要的相關資訊;在頭頸癌症中的原始資料,專家學者所建議的質量範圍以外,對於研究分析而言則並沒有實質上的幫助。 / Cancer has been the number one leading cause of death in Taiwan for the past 24 years. Early detection of this disease would significantly reduce the mortality rate. The database adopted in this study is from the Protein Mass Spectrometry Data Sets acquired and established by “Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry” (SELDI-TOF-MS) technique, including the Prostate Cancer and Head/Neck Cancer Data Sets. However, because of its high dimensionality, dealing the analysis of the raw data is not easy. Therefore, the purpose of this thesis is to search a feasible method, putting the dimension reduction and minimizing classification errors in the same time.
The data sets are separated into the experimental and controlled groups. The first step of the experimental group is to use dimension reduction by Principal Component Analysis (PCA), following by Support Vector Machine (SVM) for classification, and finally Overlap Method is used to reduce classification errors. For comparison, the controlled group uses SVM for classification. The empirical results indicate that the improvement of Overlap Method is significant in the Prostate Cancer case, but not in that of the Head/Neck case. We also study data range suggested according to the expert opinions. We find that there is information hidden outside the data range suggested by the experts in the Prostate Cancer case, but not in the Head/Neck case.
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Αποδοτικές τεχνικές προσαρμοστικής ισοστάθμισης διαύλου βασισμένες στη μέθοδο Conjugate Gradient / Efficient techniques for channel equalization based on the Conjugate Gradient methodΛάλος, Αριστείδης 16 May 2007 (has links)
Η χρήση επαναληπτικών τεχνικών προσαρμοστικής ισοστάθμισης διαύλου αποτελεί μια σχετικά πρόσφατη και πολλά υποσχόμενη μέθοδο αντιμετώπισης του φαινομένου της διασυμβολικής παρεμβολής που εισάγεται από το κανάλι λόγω του φαινομένου της πολυδιόδευσης. Ο αλγόριθμος που έχει επικρατήσει στις περισσότερες προσαρμοστικές εφαρμογές είναι ο ελαχίστων μέσων τετραγώνων (LMS). Διακρίνεται για την απλότητά του, έχει όμως φτωχές ιδιότητες σύγκλισης. Η μέθοδος των αναδρομικών ελαχίστων τετραγώνων (RLS) είναι επίσης αρκετά διαδεδομένη και κατέχει υπερέχουσες ιδιότητες σύγκλισης. Ωστόσο παρουσιάζει μεγάλη υπολογιστική πολυπλοκότητα και αυξημένες απαιτήσεις σε μνήμη. Στα πλαίσια της εργασίας αυτής εγίνε μια προσπάθεια ανάλυσης των τεχνικών που βασίζονται στη μέθοδο των συζυγών παραγώγων (Conjugate Gradient), χρησιμοποιούνται σε προβλήματα προσαρμοστικού φιλτραρίσματος και πιο ειδικά στο πρόβλημα της προσαρμοστικής ισοστάθμισης διαύλου. Οι τεχνικές αυτές επεξεργάζονται τα δεδομένα και ανά μπλοκ. Είναι ικανές να παρέχουν ιδιότητες σύγκλισης συγκρίσιμες με αυτές της (RLS) μεθόδου, εισάγοντας υπολογιστική πολυπλοκότητα ενδιάμεσων απαιτήσεων μεταξύ των μεθόδων LMS και RLS χωρίς να παρουσιάζουν προβλήματα αριθμητικής ευστάθειας. / The use of iteration methods for adaptive equalization has received considerable attention during the past several decades. The Least Mean Squares (LMS) method, which has found widespread use owing to its simplicity, has poor convergence properties. The Recursive Least Squares (RLS) method possess superior convergence properties, but it is computationally intensive and has high storage requirements for matrix manipulations. In this MSc thesis the technique of conjugate gradients is applied for the adaptive filtering problem. Conjugate gradient algorithms for adaptive filtering applications suitable for efficient implementation has been developed and has been applied for the design of an adaptive transversal equalizer. Low cost block algorithms using the preconditioned conjugate gradient method are also discussed. The algorithms are capable of providing convergence comparable to RLS schemes at a computational complexity between the LMS and the RLS methods and does not suffer from any known instability problems.
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Estrutura e ecologia trófica da Ictiofauna da microbacia do córrego Beija-Flor, Estação Ecológica de Jataí, Luiz Antônio, SPLuiz, Tatiane Ferraz 06 June 2014 (has links)
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Previous issue date: 2014-06-06 / Universidade Federal de Sao Carlos / The objective of this study was to analyze the structure, composition, trophic ecology and food items shared by the fish fauna in the stream Beija -Flor, located in Jataí Ecological Station ( 21 ⁰ 36'32 .8 " S 47 ⁰ 48'0 .54 " W ), besides characterizing the trophic ecology of the species Hemigrammus marginatus, one of the most abundant in the Beija-Flor stream. The samples of fish were collected monthly from August 2011 to July 2012, using gill nets, trawl nets and baited traps in five sampling stations distributed along the Beija-Flor stream. The fish were fixed in 10% formalin in the field and in the laboratory were identified and subjected to biometric measurements. The stomachs were weighed and transferred to 70% alcohol and stomach contents were examined under a stereomicroscope to the lowest possible taxonomic level. Forty four fish species belonging to 33 genera, 16 families and 5 orders were collected. Most species were accidental ( 43.18 % ), followed by constant species ( 38.64 % ) and accessory (18.18 % ). The diet of 30 species was analyzed. The main dietary habit was insectivorous, followed by omnivorous habits, herbivorous, piscivorous and detritivore. The dietary overlap was high in several species during periods of dry and flood. Hemigrammus marginatus was classified as an insectivore. Food items of autochthonous origin of the orders Ephemeroptera and Trichoptera were more important during the dry season, while the items of allochthonous origin of the order Hymenoptera, were more important in the rainy season. The increase in the quantity and variety of food items during the flooding causes some species of fish to become more generalist and share food resources. Hemigrammus marginatus, Astyanax altiparanae, Metynnis maculatus, Serrapinnus notomelas and Oligosarcus pintoi, have complex of interactions with the food items and can be considered key species for stream Beija- Flor. The results showed that the stream Beija-Flor is a preserved, with high species diversity by being located within the Jataí Ecological Station, but is highly threatened by being surrounded by sugar cane plantations. / O Córrego Beija-Flor, localizado na Estação Ecológica de Jataí (21⁰36 32.8 S 47⁰48 0.54 W), é formado pelos córregos da Bandeira, do Jordão e das Cabaças, e deságua no rio Mogi-Guaçu, bacia do alto Paraná. O objetivo deste trabalho foi analisar a estrutura, a composição, a ecologia trófica, e o compartilhamento de itens alimentares pela ictiofauna e caracterizar a ecologia trófica da espécie Hemigrammus marginatus, uma das espécies mais abundantes do córrego Beija-Flor. As coletas de peixes foram realizadas mensalmente no período de agosto de 2011 a julho de 2012, utilizando-se redes de espera, rede de arrasto e armadilhas iscadas do tipo covo, em cinco estações de coleta distribuídas ao longo do córrego Beija-Flor. Os peixes foram fixados em formol 10% no campo e em laboratório foram identificados e submetidos a medidas biométricas. Os estômagos foram pesados e transferidos para álcool 70% e o conteúdo estomacal foi analisado em estereomicroscópio até o menor nível taxonômico possível. Foram coletadas 44 espécies de peixes pertencentes a 33 gêneros, 16 famílias e 5 ordens. A maioria das espécies foi de ocorrência acidental (43,18 %), seguida pelas espécies constantes (38,64 %) e acessórias (18,18 %). A dieta de 30 espécies foi analisada. O principal hábito alimentar foi insetívoro, seguido pelos hábitos onívoro, herbívoro, piscívoro e detritívoro. A sobreposição alimentar foi alta em diversas espécies nos períodos de seca e cheia. Hemigrammus marginatus foi considerado insetívoro. Os itens alimentares de origem autóctone das ordens Ephemeroptera e Trichoptera foram mais importantes no período de seca, enquanto os itens de origem alóctone, da ordem Hymenoptera, tiveram maior importância no período de cheia. O aumento na quantidade e variedade de itens alimentares no período de cheia faz com que algumas espécies de peixes se tornem mais generalistas e partilhem os recursos alimentares. Hemigrammus marginatus, Astyanax altiparanae, Metynnis maculatus, Serrapinnus notomelas e Oligosarcus pintoi, possuem um complexo de interações com os itens alimentares e podem ser consideradas espécies chaves para o córrego Beija- Flor. Os resultados mostraram que o córrego Beija-Flor é um riacho preservado, com alta diversidade de espécies por estar localizado dentro da Estação Ecológica de Jataí, mas encontra-se fortemente ameaçado por estar cercado por plantações de cana de açúcar.
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Estudo espectroscópico de Cristais Eu3+:TR2O2S (TR=Y, La, Gd, Lu) através de modelos de campo cristalinoSilva, Janaelson Abilio da 29 July 2016 (has links)
In this paper we present a study of the energy position and splitting of the 7F1 and 5D1 mutiplets of the Eu3+ ion in the TR2O2S (TR = La, Gd, Y and Lu) compounds. Three models were used, namely, the point charge electrostatic model, the simple overlap model and the method of equivalent nearest neighbours. Using the coordinates of the luminescent- site, predictions of the crystal field parameters and the crystal field strength parameter and position and splitting of energy levels were performed. The electrostatic model presented good predictions only from a qualitative point of view, as expected. The same behaviour was observed when using the simple overlay model, if the charge factors entered are equal to the valence of the nearest neighbours. Using the method and a phenomenological fitting of the charge factors, in addition to satisfactorily reproduction of the data in the literature, it was observed that the dependency charge factor versus distance follows the model of Malta et al 2000, and shows increase or decrease according to the signal of the BB02parameter. / Os elementos terras raras vêm ganhando notoriedade nas mais diversas áreas de interesse tecnológico e cientifico, principalmente em função das suas características luminescentes. Nesse trabalho foi realizado um estudo do desdobramento dos mutiplitos de energia 7F1 e 5D1 dos compostos Eu:TR2O2S (TR = La, Gd, Y e Lu). Foram utilizados três modelos: o eletrostático de cargas pontuais (PCEM), de recobrimento simples (SOM) e o método dos vizinhos equivalentes (MENN). Utilizando os dados das coordenadas da estrutura do sítio luminescente. Foram realizadas previsões utilizando os modelos citados, dos parâmetros de força e campo cristalino, fatores de carga e recobrimento, intensidades dos níveis de energia e desdobramento para ambos os multipletos. O PCEM apresentou para todas estruturas resultados discrepantes em relação aos valores desejados, o mesmo comportamento observamos quando utilizado o SOM. O MENN, usando dados fenomenológico, para todos os compostos, foi o modelo que reproduziu satisfatoriamente os valores encontrados na literatura.
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Estudo do campo cristalino em oxihaletos dopados com íons Eu3+Portela, Irlan Marques Cunha 15 March 2013 (has links)
In this work we applied to a series of oxyhalides crystals, namely, GdOBr, LaOI, GdOCl, LaOCl, YOCl and LaOBr, all doped ion Eu3 +, the point charge electrostatic model (PCEM), the simple overlap model (SOM) and method of equivalent nearest neighbors (MENN), with the objective of discussing the magnitude of the charges of the ions in this halogens series. Using the local structure of luminescent site, calculations were made of the crystal field parameters and splitting of the 7F1 level. The point charge electrostatic model, as expected, led to satisfactory predictions only from the qualitative point of view. The simple overlap model and the method gave satisfactory predictions to all quantities uce the experimental splitting energy level 7F1. It is shown that the effect of O2- ions is dominant in the calculation of crystal field parameters and charge factors of the halogens has been always smaller than those of O2- ions, although in some cases the NN charge factors was greater than the their valence, when the SOM is applied. This is not completely understood up to now. / Neste trabalho foram aplicados a uma serie de cristais oxihaletos, a saber, GdOBr, LaOI, GdOCl, LaOCl, YOCl e LaOBr, todos dopados com o ion Eu3+, o Modelo Eletrostatico de Cargas Pontuais, o Modelo de Recobrimento Simples e o Metodo dos Vizinhos Equivalentes, com o objetivo de discutir a magnitude das cargas dos ions halogenios nesta serie. Usando a estrutura local do sitio luminescente, foram feitos calculos de parametros do campo cristalino (Bkq) e do desdobramento do nivel 7F1 ( ´E). O modelo eletrostatico de cargas pontuais, como esperado, levou a resultados satisfatorios apenas do ponto de vista qualitativo. Ja com o modelo de recobrimento simples e com o metodo foi possivel reproduzir ´E. As previsoes mostram que o efeito dos ions O2- e dominante nas previsoes dos Bkq e ´E e os fatores de carga dos halogenios sao muito menores que os dos ions O2-, embora em alguns casos a carga dos primeiros vizinhos tenha sido maior que a valencia respectiva, quando o modelo de recobrimento simples e aplicado, o que ainda nao e completamente entendido.
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Kernel-Based Pathway Approaches for Testing and SelectionFriedrichs, Stefanie 25 September 2017 (has links)
No description available.
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The Bantu attribute noun class prefixes and their suffixal counterparts, with special reference to ZuluMohlala, Linkie 15 March 2004 (has links)
The aim of this dissertation is to investigate the attributive noun classes, as well as their suffixal counterparts, firstly in Bantu, and secondly in Zulu. The investigation will be done with reference to aspects such as the following: the general distribution, meaning and function of the attributive noun class prefixes in Bantu. This study will also investigate the distinction between those prefixes which are exclusively used to categorise size and shape deviations, namely those belonging to classes 12/13, 19, 20, 21 and 22; and those class prefixes which have a secondary function of indicating such deviations, namely the prefixes of classes 5/6, 7/8 and 11. The main concern is the way in which these prefixes are often associated with positive or negative emotive perceptions regarding size and shape, and are therefore often used to express amelioration and derogation. In languages such as Zulu and Northern Sotho the existence of possible frozen remnants of such attributive noun class prefixes will be investigated. Some Bantu languages such as Venda that express variations in size and shape as well as the emotive perception by means of suffixes, or by a combination of prefixes and suffixes will be investigated. The possible semantic overlap between the meanings expressed by attributive class prefixes, and/or between the meanings expressed by attributive class prefixes and so-called ‘attributive suffixes’ will also be scrutinized. Apart from the aspects mentioned above, the relationship between augmentative and diminutive suffixes and the notion [+ feminine] in languages such as Zulu and Northern Sotho will be scrutinized. The occurrence of the Zulu suffix -azana/-azane, which is apparently a combination of the diminutive and augmentative suffixes, will also be investigated. This study will firstly provide a typological overview of the various strategies employed in Bantu in order to express variations in shape and size, as well as of the emotive perceptions that accompany such variations. Secondly, this study will provide an insight into the way in which shape and size variations, amelioration and derogation are expressed in Zulu through the utilisation of diminutive and augmentative suffixes. An indication will also be given of the possible diachronic development of attributive categories in this language. This study will make a significant contribution not only to the field of diachronic and comparative Bantu linguistics, but also to Zulu linguistics. This research will furthermore lead to a deeper understanding of the strategies employed in Zulu to express the semantic nuances of amelioration and derogation. / Dissertation (MA (African Languages))--University of Pretoria, 2005. / African Languages / unrestricted
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The validity of value-added measures in secondary schoolsScherman, Vanessa 19 September 2007 (has links)
The issue of quality education is a critical topic of discussion, for South Africa facing the challenge of implementation amidst a plethora of progressive policies. This research project is undertaken in collaboration with the Curriculum, Evaluation, and Management Centre (CEM) at Durham University in the United Kingdom. The Middle Years Information System (MidYIS) project was developed with the aim of providing schools with information on how learners would perform at the end of two national examinations namely Key Stage 3 and General Certificate in Secondary Education, in addition to providing value-added information. The purpose of the research reported here is to describe the procedures undertaken to explore the feasibility of implementing the MidYIS system in the South African context. The research was guided by two main research questions. The first research main research question is how appropriate is the Middle Years Information System (MidYIS) as a monitoring system in the South African context? The word “appropriate” here interrogates the suitability of the MidYIS system for South Africa looking specifically at validity and reliability issues. This non-experimental study used a mixed methods design, rooted in pragmatism, to explore validity and reliability issues of using MidYIS as a possible monitoring system that would provide a balanced view of the school’s contribution to academic gains made by learners. The sample included in the study ranged from National Department of Education officials (two officials from curriculum and assessment), Provincial Department of Education officials (one mathematics specialist, one language specialist and one specialist from the Gauteng Department of Education Office for Standards in Education), specialists in the field of language, mathematics, and psychology as well as 11 schools. In particular content-related validity (including curriculum validity), construct-related validity, and predictive validity were examined while inferences drawn with regard to reliability were done by means of internal consistency reliability. From a curriculum perspective for content-related validity, it was found that there was moderate curriculum validity for language while inferences drawn for mathematics were substantially stronger. For content-related validity from a psychometric perspective, it was found that there was overlap between the domain of developed abilities and the MidYIS assessment. Construct-related validity was explored by means of Rasch analysis and it was found that items in the MidYIS assessment tend to form well-defined constructs. Predictive validity was explored by means of correlation analysis between the MidYIS assessment and school-based results in language and mathematics. The analysis shows that it could be possible to use the MidYIS assessment for prediction purposes. However, additional research would be needed to explore this facet of validity further with a larger sample and using standardised school-based results. The MidYIS assessment was found to be reliable for the sample as a whole as well as for population groups within the sample. The second main research question extends the first research question. If MidYIS is valid, with South African adaptations, and reliable, then what factors on a school, classroom, and learner-level could have an effect on learner performance. Thus, the second main research question is which factors could have an effect on learner performance and therefore inform the design of the monitoring system? In order to explore factors, multilevel analysis was undertaken on the various levels within the school system namely the principals, mathematics and language educators, as well as learners who completed questionnaires. It was found that four learner-level factors (with whom learners live, mother’s level of education, importance of mathematics and importance of English), one educator level factor (challenges to assessment due to lack of in-service training) and two school-level factors (educators make use of monitoring systems and encouraging academic achievement) seem to have an effect on the performance of learners. / Thesis (PhD (Assessment and Quality Assurance in Education and Training))--University of Pretoria, 2007. / Curriculum Studies / PhD / Unrestricted
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Two-dimensional Study of Blade Profiles for a Savonius Wind TurbineSundberg, Johanna, Lundberg, Martina, Solhed, Julia, Manousidou, Aikaterini January 2020 (has links)
A Savonius wind turbine is a self-starting vertical axis rotor. It can be designed to be compact in size and also produces less noise which makes it suitable to integrate into urban spaces such as rooftops and sign-poles. These characteristics make it interesting from a sustainability point of view, especially when aiming to increase the decentralization of electricity production. This thesis aimed to investigate the aerodynamic performance of different two-bladed Savonius profiles by varying the blade arc angle and the overlap ratio. For evaluation, the dimensionless power coefficient and torque coefficient were investigated over different tip speed ratios. The study was conducted numerically with 2D simulations in Ansys Fluent. The partial differential equations describing the characteristics of the flow, including the flow turbulence effects, were solved with the Reynolds-average Navier Stokes in combination with the k-omega SST model. A validation was performed by comparing data from simulated and experimental tests of a semi-circular profile and a Benesh profile. The investigation of the blade arc angle and overlap ratio was performed on a Modified Bach profile. The profile with a blade arc angle of 130 degrees and an overlap ratio of 0.56 generated a maximal power coefficient of 0.267 at a tip speed ratio of 0.9. This blade configuration generated the best performance of all conducted simulations in this project. However, this project contained uncertainties since simulations can never be an exact description of reality. The project was also limited by the computational power available. Nevertheless, according to the conducted simulations, it was observed that a higher blade arc angle and a larger overlap ratio seem to generate higher efficiency. / En Savonius vindturbin är en självstartande vertikalaxlad rotor som kan utformas i en kompakt design samtidigt som den producerar mindre oljud än horisontalaxlade vindkraftverk. Dagens hållbarhetssträvan i kombination med Savonius turbinens karakteristiska egenskaper gör den till ett potentiellt starkt vertyg för vindenergi. Då den kan placeras på exempelvis hustak eller skyltstolpar, utan att störa närliggande omgivning, finns det många möjliga sätt att implementera och integrera den i samhällets infrastruktur. Målet med detta projekt var att undersöka den aerodynamiska prestationen för Savoniusturbiner med två blad genom att variera bladvinkeln och överlappningsförhållandet. För att jämföra de olika profilerna användes den dimensionslösa effektkoefficienten och momentkoefficienten. Dessa koefficienter beräknades i förhållande till löptalet. Studien utfördes numeriskt med 2D-simuleringar i Ansys Fluent. De partiella differentialekvationerna som beskriver flödets egenskaper, inkluderat turbulenseffekterna, löstes med Reynolds-average Navier Stokes i kombination med k-ω SST modellen. En validering utfördes genom att jämföra data med simulerade och experimentella värden av en Semi-circular profil och en Benesh profil. Studien av bladvinkel och överlappningsförhållandet utgick från en Modified Bach profil. Den mest effektiva profilen hade en bladvinkel av 130 grader och ett överlappsförhållande på 0,56. Den genererade en maximal effektkoefficient av 0,267 vid löptal 0,9. Projektet innehöll en del osäkerheter då simuleringar aldrig kan beskriva verkligheten till fullo. Den tillgängliga beräkningskapaciteten begränsade även projektet ytterligare. Trots vissa begränsningar, visar ändå utförda simuleringar att ökad bladvinkel och ökat överlappningsförhållande genererar högre effekt. / <p>This project was conducted within Stand up for wind and Stand up for energy.</p>
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Sací kanály Wankelova motoru / Intake Ports for the Wankel EngineSmělý, Jiří January 2017 (has links)
This master’s thesis deals with design of intake port for turbocharged Mazda 13B-T engine with Wankel-type rotating piston motion aiming for possible modifications leading to increase of performance parameters. The main objective of this thesis is to propose appropriate modifications in order to achieve increased torque in widest possible engine speed range.
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