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Prévalence, description et facteurs de risque de l’antibiorésistance dans les fermes québécoises de bovins laitiersMassé, Jonathan 10 1900 (has links)
La résistance aux antimicrobiens (RAM) est un problème de santé publique mondial avec des répercussions importantes en médecine vétérinaire et humaine. Elle est classiquement associée à une surutilisation des antimicrobiens. Les bactéries commensales des animaux et des humains, tel Escherichia coli, sont souvent utilisées comme bactéries indicatrices pour surveiller la RAM. Parmi les mécanismes de résistance de E. coli, la production de β-lactamases à spectre étendue (BLSE) ou de type AmpC est particulièrement inquiétante. Ces enzymes peuvent inactiver une classe d’antimicrobien de très haute importance en santé humaine également utilisée en médecine vétérinaire : les céphalosporines de 3e génération. La prévalence générale de la RAM ainsi que la présence de E. coli producteur de BLSE/AmpC dans les troupeaux laitiers québécois sont inconnues. De plus, la transmission de ces bactéries résistantes et les facteurs de risque associés à leurs excrétions par les bovins laitiers sont actuellement peu documentés. L’objectif général de cette thèse était d’explorer la RAM par une étude transversale observationnelle sur des fermes québécoises de bovins laitiers sélectionnées aléatoirement (n = 101). La première étape du projet constituait à décrire la prévalence de cette RAM pour la bactérie E. coli isolée des matières fécales des animaux (vaches en lactation, veaux pré-sevrage) et de l’environnement (fosse à fumier). La prévalence de RAM observée pour les E. coli indicateurs était faible (<5%) pour les antimicrobiens de très haute importance en médecine humaine (céphalosporines de 3e génération et fluoroquinolones). Cependant, il y avait une prévalence élevée (85%) de fermes avec la présence d’au moins un E. coli producteur de BLSE/AmpC. La RAM était particulièrement importante pour les E. coli isolés chez les veaux pré-sevrage. Pour la deuxième étape, cette RAM était analysée au niveau génétique par le séquençage du génome entier des E. coli les plus résistants. La grande majorité de la RAM (>95%) était expliquée par des mutations ou des gènes de résistance. Certains de ceux-ci étaient à proximité l’un de l’autre et leur configuration laissait supposer qu’une partie de ces gènes étaient présents sur des éléments génétiques mobiles. De plus, il y avait une dissémination clonale de E. coli résistant entre les fermes. La dernière étape constituait à déterminer des facteurs de risque (utilisation des antimicrobiens ou pratiques à la ferme) de la RAM. Grâce à des analyses multivariées utilisant l’intelligence artificielle, il a été possible d’observer des facteurs de risque significatifs associés à la taille de la ferme et à la santé des animaux. Bref, un portrait de la situation de la RAM est maintenant établi dans les troupeaux de bovins laitiers du Québec pour 2017. Il s’agit d’un phénomène complexe qui ne se limite pas simplement à un lien direct avec l’utilisation des antimicrobiens. Ces travaux serviront de bases pour suivre l’évolution temporelle de la RAM. De plus, des études prospectives pourraient être réalisées afin de confirmer les impacts des observations notées dans cette thèse. L’ensemble de ces informations seront déterminantes en vue d’établir des mesures concrètes pour tenter de limiter cette importante problématique. / Antimicrobial resistance (AMR) is a global public health problem with major repercussions in both veterinary and human medicine. It is classically associated with the overuse of antimicrobials. Animal and human commensal bacteria, such as Escherichia coli, are often used as indicator bacteria to monitor AMR. Among the resistance mechanisms of E. coli, the production of an extended-spectrum β-lactamase (ESBL) or AmpC-type is of particular concern. These enzymes can inactivate a class of antimicrobials of great importance in human health also used in veterinary medicine: third-generation cephalosporins. The overall prevalence of AMR and the presence of ESBL/AmpC-producing E. coli are unknown in Québec dairy herds. Furthermore, the transmission of these resistant bacteria and the risk factors associated with their excretion by dairy cattle are currently poorly documented. The overall objective of this thesis was to explore AMR through an observational cross-sectional study on randomly selected Québec dairy farms (n = 101). The first step of the project was to describe the prevalence of AMR for E. coli isolated from animal feces (lactating cows, pre-weaned calves) and the environment (manure pit). The prevalence of AMR observed for indicator E. coli was low (<5%) for antimicrobials of very high importance in human medicine (third-generation cephalosporins and fluoroquinolones). However, there was a high prevalence (85%) of farms with at least one ESBL/AmpC-producing E. coli. AMR was particularly high for E. coli isolated from pre-weaned calves. In the second step, AMR was analyzed at the genetic level by whole genome sequencing of the most resistant E. coli isolates. The vast majority of AMR (>95%) was explained by mutations or resistance genes. Some of these were in close proximity to each other, and their configuration suggested that some of these genes were present on mobile genetic elements. In addition, there was clonal dissemination of resistant E. coli between farms. The final step was to identify risk factors (antimicrobial use or farm practices) for AMR. Using artificial intelligence methods for multivariate analyses, it was possible to identify significant risk factors associated with farm size and the health of animals. In summary, our results provide a portrait of the AMR situation in Québec dairy herds. This complex phenomenon is not simply limited to a direct link with antimicrobial use. This work will serve as a baseline for monitoring the temporal evolution of AMR. In addition, prospective studies could be carried out to confirm the impacts of the observations noted in this thesis. All this information will be decisive in establishing concrete measures to try and limit this major problem.
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Applications of Adaptive Antennas in Third-Generation Mobile Communications SystemsLau, Buon Kiong January 2002 (has links)
Adaptive antenna systems (AAS's) are traditionally of interest only in radar and sonar applications. However, since the onset of the explosive growth in demand for wireless communications during the 1990's, researchers are giving increasing attention to the use of AAS technology to overcome practical challenges in providing the service. The main benefit of the technology lies in its ability to exploit the spatial domain, on top of the temporal and frequency domains, to improve on transceiver performance. This thesis presents a unified study on two classes of preprocessing techniques for uniform circular arrays (UCA's). UCA's are of interest because of their natural ability to provide a full azimuth (i.e. 360') coverage found in typical scenarios for sensor array applications, such as radar, sonar and wireless communications. The two classes of preprocessing techniques studied are the Davies transformation and the interpolated array transformations. These techniques yield a mathematically more convenient form - the Vandermonde form - for the array steering vector via a linear transformation. The Vandermonde form is useful for different applications such as direction-of-arrival (DOA) estimation and optimum or minimum variance distortionless response (MVDR) beamforming in correlated signal environment and beampattem synthesis. A novel interpolated array transformation is proposed to overcome limitations in the existing interpolated array transformations. A disadvantage of the two classes of preprocessing techniques for UCA's with omnidirectional elements is the lack of robustness in the transformed array steering vector to array imperfections under certain conditions. In order to mitigate the robustness problem, optimisation problems are formulated to modify the transformation matrices. / Suitable optimisation techniques are then applied to obtain more robust transformations. The improved transformations are shown to improve robustness but at the cost of larger transformation errors. The benefits of the robustification procedure are most apparent in DOA estimation. In addition to the algorithm level studies, the thesis also investigates the use of AAS technology with respect to two different third generation (3G) mobile communications systems: Enhanced Data rates for Global Evolution (EDGE) and Wideband Code Division Multiple Access (WCDMA). EDGE, or more generally GSM/EDGE Radio Access Network (GERAN), is the evolution of the widely successful GSM system to provide 3G mobile services in the existing radio spectrum. It builds on the TDMA technology of GSM and relies on improved coding and higher order modulation schemes to provide packet-based services at high data rates. WCDMA, on the other hand, is based on CDMA technology and is specially designed and streamlined for 3G mobile services. For WCDMA, a single-user approach to DOA estimation which utilises the user spreading code and the pulse-shaped chip waveform is proposed. It is shown that the proposed approach produces promising performance improvements. The studies with EDGE are concerned with the evaluation of a simple AAS at the system and link levels. / Results from, the system and link level simulations are presented to demonstrate the effectiveness of AAS technology in the new mobile communications system. Finally, it is noted that the WCDMA and EDGE link level simulations employ the newly developed COST259 directional channel model, which is capable of producing accurate channel realisations of macrocell environments for the evaluation of AAS's.
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台灣與日本金融危機之比較研究 / Copmartive Study of Financial Crisis Between Taiwan & Japan王建民, Wang, Chien-Min Unknown Date (has links)
一、金融危機的理論模型可分為:1.第一代模型:基本面惡化。2.第二代模型:傳染蔓延效果。3.第三代模型:預期心理效果。
二、台灣發生金融危機的成因為:1.土地投機過深。2.股票持有過多。3.交叉持股,過度融資。4.借殼上市。
三、台灣發生金融危機的後果為: 1.資產價格下跌,影響家計消費。2.經濟成長率下降。3.銀行業逾放比率增加、資產品質惡化、退票比率增加、資產報酬率下降。
四、台灣發生金融危機政府採取的因應對策及其效果為:1.一般性管制。2.選擇性信用管制。3.調降金融業營業稅:降稅所增加的盈餘,幫助銀行沖銷呆帳,降低逾放比率。4.金融業合併:(1)業務同性質很高,將以節省成本為主要目的。(2)官股成分的銀行進行合併。5.展延問題企業本息攤還半年。6.護盤:(1)企業界護盤:釀成母子公司財務危機。(2)財政部成立「股市穩定基金小組」。7.銀行業不動產擔保品需於兩年內處分完畢。8.限制分行設立家數,誘導新銀行承受信用合作社。9.嚴禁抽銀根,以配合政府紓困政策。
五、日本發生金融危機的成因為:1.政界、官員、財界與黑道操縱股價。2.交叉持股,過度融資。3.土地投機過深。4.大藏省及日銀失職。5.決策當局無法適當處理。
六、日本發生金融危機的後果為:1.經濟成長停滯。2.企業部門財務結構惡化、破產家數及債務創新高。3.失業率創新高。4.財政赤字惡化及國民負擔增加。5.金融機構債信評等下降、資本適足性規定與股、匯市重挫導致金融機構惜貸。6.銀行業逾放比率增加、資產品質惡化、資產報酬率下降。7.資產價格下跌,影響家計消費。
七、日本發生金融危機政府採取的因應對策及其效果為:
(一)振興景氣方案成效評析:自1992年起推出多次振興經濟方案,惟未進行制度面及供給面結構改革,銀行龐大呆帳問題一再拖延,財政赤字不斷擴大。
(二)租稅政策成效評析: 1997年提高消費稅稅率並廢除特別減稅措施,且增加醫療保險自負額,同時公共投資減少3兆日圓,被認為是振興經濟的絆腳石。
(三)貨幣政策成效評析:貼現率由1993年8月30日的6%逐漸調降至歷史新低點,但寬鬆貨幣政策的效果,幾乎無法發揮。
(四)金融改革成效評析:1.1996年:實施金融大改革,逐步解除金融市場各項管制,期望在2001年可以與紐約、倫敦的金融市場並駕其驅;但卻在1997年中為金融風暴所阻。2.1997年:(1)通過日銀法修正法案,賦予日銀自主性。(2)大藏省改革法案,可下令銀行停止營業,而不再採行事前指導與保護。3.1998年:實施(1)「新外匯化」、「金融系統改革法」、「金融機能安定化法」、「存款保險修正法案」:以公共資金購買特別股方式挹注銀行資本,由於挹注金額過低,且外界對審查過程質疑甚深。(3)實施「金融再生法」:成立「金融再生委員會」,解決問題銀行;同時合併住專管理公司與處理回收銀行:專司負責處理銀行不良債權;惟面臨適任人選不足的問題。同時與大藏省共同管理,故其「獨立」、「專責」的角色亦受到質疑。 (4)實施「金融早期健全法案」:率先對受困的金融機構提供援助。4.1999年:對大型銀行、地方銀行的官方資金投入期限至2001年3月底止,防金融界的過度依賴。5.2000年:成立金融廳,強化金融體系,確保金融管理的透明化,加強與國際合作為職志。
八、台灣與日本金融危機的比較
(一)相同點:1.外債小於外匯存底。2.內債赤字逐漸擴大。3.貿易收支都有盈餘,惟貿易盈餘與國內投資有趨緩的現象,造成經濟成長率下降,股、匯市下跌。4.有產業及資金外移的現象。5.銀行有特權貸放,造成道德危機與逆選擇。
(二)相異點:1.技術層次不同:日本的研發水準有其獨特之處,台灣OEM較多,大都接美、日訂單,受美、日景氣衰退的影響既大且深。2.政治穩定性不同:日本長達近10年的短命內閣,政策前後無法一致性,責任承擔不明,台灣則無此現象。3.佔世界經濟體的地位不同:日本佔世界經濟體第二大,台灣佔世界經濟體第二十一大,所以日本的產能比台灣大。4.工資與地租成本結構不同:日本的工資與地租成本是台灣的2.5倍,所以景氣下滑較早發生,趨緩的時間亦較長。
九、台灣與日本金融危機經驗給吾人之改革啟示
(一)在銀行制度應有的改革:1.強化金融監理體系,力求金融監理一元化。2.鼓勵金融機構合併。3.設立資產管理公司。4.成立控股公司。
(二)在貨幣市場應有的改革:1.發行票券的公司需經信用評等。2.建立票券業務防火牆及內控制度。3.貨幣市場共同基金與銀行體系進行競爭,可提升競爭力。
(三)在資本市場應有的改革:1.降低股市的財務槓桿比率,適度調低融資成數。2.加強查緝丙種經紀人。3.提高法人投資比重,使市場結構趨於穩定,降低股市的波動性。4.加強取締內線交易。
(四)在外匯市場應有的改革:1.匯率制度儘量尊重市場供需機能。2.如果外債過高,過度引進外資易造成金融機構信用過度膨脹。而企業負債比例過高、若資金過度流向股市及不動產投機市場,金融機構易導致鉅額呆帳或倒閉。3.央行對無本金交割遠期外匯投機交易應有嚴格的規定,避免外匯過度投機。
(五)在產業政策應有的改革:1.未來高科技的發展,不應再依循以往政府專案資助的模式,宜交由市場機制,自行運作。2.政府只要提供良好的投資環境,並建立良好的制度與規範。3.企業界需培植高級人才,提升研發能力。
十、結論:(一)發生金融危機,市場運作偏離常軌,政府的短期救急措施顯得非常重要。(二)就中長期而言,為加速經濟結構的調整,因應泡沫經濟的衝擊,政府由擴大公共投資、貫徹自由化政策及加速產業升級三方面著手。(三)日本振興經濟方案偏重公共投資,且方案執行有時間落後。(四)日本財政赤字嚴重惡化,影響經濟復甦腳步。(五)日本主政者未針對經濟的病因,進行結構性改革。
十一、政策性意含:(一)慎評擴大內需效果。(二)貨幣政策應同時兼顧內需市場與國際市場。(三)政府需研擬整套金融改革方案。(四)日本金融改革給台灣的啟示。
第一章 緒論----------------------------------------------------1
第一節 研究背景與目的--------------------------------------1
第二節 研究內容與架構--------------------------------------4
第三節 研究方法與限制--------------------------------------7
第四節 研究期間與資料來源之限制----------------------------7
第五節 文獻回顧--------------------------------------------7
第二章 台灣金融危機的成因、後果及政府因應對策-----------------15
第一節 台灣金融危機的期間與背景---------------------------15
第二節 台灣金融危機的成因分析-----------------------------19
第三節 台灣金融危機的後果分析-----------------------------32
第四節 台灣金融危機的政府因應對策-------------------------40
第五節 台灣金融危機的政府因應對策效果評析-----------------58
第三章 日本金融危機的成因、後果及政府因應對策-----------------70
第一節 日本金融危機的期間與背景---------------------------70
第二節 日本金融危機的成因分析---------------------------- 78
第三節 日本金融危機的後果分析---------------------------- 85
第四節 日本金融危機的政府因應對策-------------------------89
第五節 日本金融危機的政府因應對策效果評析--------------------103
第四章 台灣與日本金融危機的成因、後果及政府因應對策
之比較----------------------------------------------- 114
第一節 台、日金融危機成因之比較分析----------------------114
第二節 台、日金融危機後果之比較分析----------------------119
第三節 台、日金融危機政府因應對策之比較分析--------------125
第四節 台、日金融危機政府因應對策效果之比較分析----------142
第五章 台灣與日本金融危機經驗給吾人之改革啟示----------------146
第一節 在銀行制度應有的改革------------------------------146
第二節 在貨幣市場應有的改革------------------------------154
第三節 在資本市場應有的改革------------------------------157
第四節 在外匯市場應有的改革------------------------------161
第五節 在產業政策應有的改革----------------------------------163
第六章 結論--------------------------------------------------166
第一節 本文主要發現--------------------------------------166
第二節 本文政策性意涵------------------------------------169
註 釋-----------------------------------------------------174
參考書目-----------------------------------------------------178
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Μελέτη φυσικού επιπέδου τηλεπικοινωνιακών συστημάτων 3ης γενιάς και εξομοίωση καναλιού PRACH ανερχόμενης ζεύξης κατά την προτυποποίηση 3GPPΠαναγιωτακοπούλου, Αγγελική 15 January 2009 (has links)
Η παρούσα διπλωματική εργασία έγινε στα πλαίσια του Προγράμματος Μεταπτυχιακών Σπουδών Ηλεκτρονικής και Υπολογιστών, στο Τμήμα Φυσικής του Πανεπιστημίου Πατρών. Αντικείμενό της αποτελεί η μελέτη του φυσικού επιπέδου συστημάτων κινητής τηλεφωνίας τρίτης γενιάς και η εξομοίωση χαρακτηριστικού καναλιού του φυσικού επιπέδου σύμφωνα με την παγκόσμια προτυποποίηση 3GPP.
Στο πρώτο κεφάλαιο γίνεται ιστορική ανασκόπηση των συστημάτων προηγούμενων γενεών. Αναφέρονται βασικά προβλήματα που πρέπει να αντιμετωπίσει ένα τηλεπικοινωνιακό σύστημα καθώς και η βασική δομή των κυψελοειδών συστημάτων. Γίνεται εισαγωγή στα συστήματα τρίτης γενιάς ως προς τις απαιτήσεις, τις υπηρεσίες που προσφέρουν, την προτυποποίηση και την αρχιτεκτονική τους.
Στο δεύτερο κεφάλαιο μελετώνται οι τρόποι πολλαπλής πρόσβασης με ιδιαίτερη έμφαση στην προσπέλαση με διαίρεση κωδικών. Αναλύονται τα συστήματα διάχυσης φάσματος. Γίνεται εκτενής αναφορά και υλοποίηση προγραμμάτων για τις ψευδοτυχαίες ακολουθίες και τις ακολουθίες Gold.
Στο τρίτο κεφάλαιο μελετάται η δομή δικτύων επικοινωνίας κατά το μοντέλο OSI. Αναφέρονται τα επίπεδα των τηλεπικοινωνιακών συστημάτων με διεξοδική μελέτη του φυσικού επιπέδου και στις διεπαφές που χρησιμοποιεί για επικοινωνία καθώς και στις υπηρεσίες που προσφέρει. Αναλύεται η δομή όλων των φυσικών καναλιών και εξομοιώνεται η διαδικασία ενθυλάκωσης του καναλιού PRACH.
Στο τέταρτο κεφάλαιο αναλύονται οι κώδικες διάχυσης των φυσικών καναλιών ανερχόμενης ζεύξης καθώς και η διαδικασία διάχυσης τους. Δημιουργούνται προγράμματα που παράγουν αυτούς τους κώδικες και γίνεται εξομοίωση της διάχυσης και της αποδιάχυσης του PRACH καναλιού.
Στο πέμπτο κεφάλαιο αναφέρεται η διαδικασία κωδικοποίησης πηγής και μελετάται η PSK διαμόρφωση και αποδιαμόρφωση που χρησιμοποιούν τα συστήματα τρίτης γενιάς. Υλοποιούνται προγράμματα που εξομοιώνουν τη συνολική διαδικασία σε ενθόρυβο κανάλι AWGN μελετώντας την επίδραση του θορύβου σε μεταδιδόμενο σήμα.
Όλες οι εξομοιώσεις υλοποιήθηκαν με το πρόγραμμα Matlab 7.1. / This master thesis is a part of the post-graduate course of the Physics department of the University of Patras, on Electronics and Computers. Its main objective is the study of the physical layer of 3rd generation telecommunication systems and the simulation of a particular channel, in accordance to 3GPP specifications.
In the first chapter we review telecommunication systems of previous generations. We also refer to major problems that need to be dealt with and also the basic structure of cellular networks. 3rd generation telecommunication systems, their requirements, offered services, standardisation and architecture are all introduced.
In the second chapter we study multiple access methods, emphasising CDMA methods. Moreover, spread spectrum systems are analysed. Finally we refer to pseudorandom and Gold sequences. Programs are created which generate these sequences.
In the third chapter we look into the structure of communication networks according to the OSI model. The layers of telecommunication systems are mentioned, laying emphasis on the physical layer, the interfaces used for communication as well as the offered services. We report all physical channels and we simulate the encapsulation of the PRACH channel.
In the fourth chapter we analyse the spreading and scrambling codes referring to the uplink channels. Next we point out the code allocation process. Programs are created which generate these spreading and scrambling codes and we finally simulate the spreading and de-spreading process of the PRACH channel.
In the fifth chapter we outline the source coding process using PCM, and we study PSK modulation and demodulation which are used by 3rd generation telecommunication systems. We create programs that simulate the whole procedure in a noisy channel, and we study the effect of AWGN.
The programs were created and the simulations were run using Matlab version 7.1.
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Remediation of instability in Best Linear Unbiased PredictionEatwell, Karen Anne January 2013 (has links)
In most breeding programmes breeders use phenotypic data obtained in breeding trials
to rank the performance of the parents or progeny on pre-selected performance criteria.
Through this ranking the best candidates are identified and selected for breeding or
production purposes. Best Linear Unbiased Prediction (BLUP), is an efficient selection
method to use, combining information into a single index. Unbalanced or messy data is
frequently found in tree breeding trial data. Trial individuals are related and a degree of
correlation is expected between individuals over sites, which can lead to collinearity in
the data which may lead to instability in certain selection models. A high degree of
collinearity may cause problems and adversely affect the prediction of the breeding
values in a BLUP selection index. Simulation studies have highlighted that instability is
a concern and needs to be investigated in experimental data. The occurrence of
instability, relating to collinearity, in BLUP of tree breeding data and possible methods
to deal with it were investigated in this study. Case study data from 39 forestry
breeding trials (three generations) of Eucalyptus grandis and 20 trials of Pinus patula
(two generations) were used. A series of BLUP predictions (rankings) using three
selection traits and 10 economic weighting sets were made. Backward and forward
prediction models with three different matrix inversion techniques (singular value
decomposition, Gaussian elimination - partial and full pivoting) and an adapted ridge
regression technique were used in calculating BLUP indices. A Delphi and Clipper
version of the same BLUP programme which run with different computational numerical precision were used and compared. Predicted breeding values (forward
prediction) were determined in the F1 and F2 E. grandis trials and F1 P. patula trials and
realised breeding performance (backward prediction) was determined in the F2 and F3 E.
grandis trials and F2 P. patula trials. The accuracy (correlation between the predicted
breeding values and realised breeding performance) was estimated in order to assess the
efficiency of the predictions and evaluate the different matrix inversion methods. The
magnitude of the accuracy (correlations) was found to mostly be of acceptable
magnitude when compared to the heritability of the compound weighted trait in the F1F2
E. grandis scenarios. Realised genetic gains were also calculated for each method used.
Instability was observed in both E. grandis and P. patula breeding data in the study, and
this may cause a significant loss in realised genetic gains. Instability can be identified by examining the matrix calculated from the product of the phenotypic covariance
matrix with its inverse, for deviations from the expected identity pattern. Results of this
study indicate that it may not always be optimal to use a higher numerical precision
programme when there is collinearity in the data and instability in the matrix
calculations. In some cases, where there is a large amount of collinearity, the use of a
higher precision programme for BLUP calculations can significantly increase or
decrease the accuracy of the rankings. The different matrix inversion techniques
particularly SVD and adapted ridge regression did not perform much better than the full
pivoting technique. The study found that it is beneficial to use the full pivoting
Gaussian elimination matrix inversion technique in preference to the partial pivoting
Gaussian elimination matrix inversion technique for both high and lower numerical
precision programmes. / Thesis (PhD)--University of Pretoria, 2013. / gm2014 / Genetics / unrestricted
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The efficacy of teaching practice implemented by the University of ZambiaLuchembe, Musonda 11 November 2020 (has links)
Abstract in English, Zulu and Venda / For many years, the process of training a teacher has been extensively studied and debated in the scientific and academic community worldwide. However, the literature reviewed for the study revealed that few studies have been conducted on teaching practice in Zambia. The aim of this study was to determine the efficacy of the teaching practice programme of the University of Zambia, to identify its challenges and to propose improvements. This study was therefore guided by the following main research question: How effective is teaching practice conducted by the University of Zambia for the preparation of teachers to teach in secondary schools in Zambia?
The study is informed by the third generation activity theory perspective. It is situated in the qualitative approach and the underlying epistemology is interpretive. The sample population was purposively selected and comprised the „triad‟: 8 teacher educators, 24 student teachers, and 10 supervising teachers. Data were collected from interviews, focus groups and lesson evaluation forms. The data from the interviews and focus groups were analysed thematically, while the data from lesson evaluation forms were analysed using the content analysis method. To present and analyse the participants‟ views, key themes were identified, which included the lack of clarity and consensus on the role of supervising teachers in teaching practice, and that the implementation of teaching practice is beset with many challenges.
The study established that the short period for the implementation of teaching practice was a critical challenge to providing quality training to student teachers. Inadequate funds for teaching and learning materials and a lack of clarity and consensus on the role of supervising teachers in teaching practice were among the challenges. Most of the study‟s findings are consistent with earlier studies. One such finding was that student teachers demonstrated mastery of subject matter but had inadequate knowledge and skills in teaching methodology. Based on the evidence collected and analysed, the researcher established that the teaching practice implemented by the University of Zambia in schools is ineffective. Therefore, this study ends with recommendations to make the implementation of teaching practice by the University of Zambia in schools effective. One of the recommendations is that the School of Education should be separated from other faculties so that more time can be devoted to training and actual teaching practice in schools. / Iminyaka eminingi, inqubo yoqeqesho lothisha sekucwaningwe ngayo kanye nokuxoxisana ngayo ngososayense kanye nama-akhademiki kuwo wonke umhlaba. Imibhalo ebuyekeziwe ngocwaningo lwamanje, kodwa iveze ukuthi, bambalwa abacwaningi abaphenyisise ngezinqubo zokufundisa eZambia. Ucwaningo lwamanje belufuna ukubheka ukusebenza kohlelo lwenqubo yokufundisa, okwenziwa eYunivesithi yaseZambia, ngenhloso yokubona izinselele kanye nokuphakamisa izindlela zokuthuthukisa. Lo msebenzi ubuholelwa ngumbuzo wocwaningo olandelayo: Ngabe isebenza kanjani inqubo yokufundisa eyenziwa yiYunivesithi yeZambia, ukulungiselela othisha ukufundisa kwizikole zamasekondari eZambia?
Ngokuholelwa yi-third-generation activity theory perspective, ucwaningo lusebenzise inqubo ye-qualitative kanye ne-interpretive ngaphansi kohlelo lwe-epistemology. Abantu okuthathwe kubo isampuli, ehlelwe ngenhloso ibiqukethe i-'triad' yabafundisi bothisha, izitshudeni ezifundela ukufundisa kanye nothisha abasuphavayisayo. Kuqoqwe idata (ulwazi) ngokusebenzisa ama-interview, ama-focus group kanye namafomu okuhlola izifundo, ngemuva kwalokho idata etholakele kuqala yahlaziywa ngokulandela izihloko (thematically), kanti idata yakamuva yona kwenziwa uhlaziyo lwengqikithi (content analysis) ngayo. Ukwethula kanye nokuhlaziya imibono yababambiqhaza, kwabonwa izihloko (themes) ezisemqoka, phakathi kwazo kwaba nokungaqiniseki kahle ngendima edlalwa ngothisha abasuphavayisayo kwinqubo yokufundisa, kanye nezihibe ekusebenzeni ngokulandela inqubo yokufundisa.
Imiphumela iveze ukuthi isikhathi esifishane esibekiwe sokusebenzisa inqubo yokufundisa sibangele inselele esemqoka maqondana neqophelo loqeqesho olunikezwa izitshudeni zothisha. Akunamali elingene yokuthola imetheriyali yezinto zokufundisa kanye nokufunda, kanti futhi kunokungacaci kahle kanye nokungavumelani ngendima yothisha abasuphavayisayo kwinqubo yokufundisa, nakho lokhu kwabikwa. Ngisho noma imiphumela yocwaningo ihambelana nemisebenzi yangaphambilini, okutholakele okusemqoka kube wukuthi izitshudeni zothisha zikwazile ukukhombisa ukuqondisisa kwazo ngengqikithi yezifundo (subject matter), kodwa bezingenalwazi olwanele, namakhono ngemetodoloji yokufundisa. Ngokulandela ubufakazi obuqoqiwe bahlaziywa, umcwaningi uthole ukuthi inqubo yokufundisa yabathwebule izifundo eYunivesithi yaseZambiwa, abayisebenzisayo ezikoleni, ayisebenzi ngokufanele. Lolu cwaningo, luphethe ngezincomo zokushintsha lesi simo, esinye sazo wukuthi i-School of Education kumele sihlukaniswe namanye amafakhalthi, ukuze kusetshenziswe isikhathi esiningi kugxilwa kakhulu ekuqeqeshweni kothisha kanye nenqubo yokufundisa ezikoleni. / Ndi miṅwaha minzhi, maitele a u gudisa vhadededzi a tshi khou gudiwa nga vhuroṅwane na u haseledzwa nga zwitshavha zwa saintsi na zwa akademi u mona na ḽifhasi. Maṅwalwa a zwine zwa tea u itwa zwino o bvisela khagala uri, fhedzi, hu na vhaṱoḓisisi vha si gathi vho sengulusaho kufunzele kwa Zambia. Ngudo dza zwino dzo lwela u vhona u vhona u shuma ha mbekanyamushumo ya nḓowenḓowe dza u funza ine ya ṋekedzwa nga Yunivesithi ya Zambia, ho sedzwa u topola khaedu na u dzinginya zwine zwa tea u khwiṋiswa. Zwiito izwi zwo endedzwa nga mbudziso khulwane ya ṱhoḓisiso i tevhelaho: Nḓowenḓowe dza u funza dzine dza khou itwa ngei Yunivesithi ya Zambia dzi khou shuma u swika ngafhi, u lugisela vhadededzi uri vha kone u funza kha zwikolo zwa sekondari zwa Zambia?
Musi zwi khou ḓisendeka nga nyito dza murafho wa vhuraru wa kuvhonele kwa thyeori, ngudo dzo shumisa maitele a u sedza ndeme na thyeori ya nḓivho ya kuṱalutshedzele kwa zwi re ngomu. Sambula ya tshitshavha, ye ya nanguludzwa hu na ndivho, yo vha i na „zwigwada zwa vhathu nga vhararu‟ vha vhadededzi, matshudeni a gudelaho vhudededzi na vhalavhelesi vha zwa vhudededzi. Data yo kuvhanganywiwa nga kha inthaviwu, zwigwada zwo sedzwaho na fomo dza u ela ngudo, zwine nga murahu data yo wanalaho kha izwi zwivhili zwa u thoma ya kona u saukanywa u ya nga thero, ngeno data ya zwa u fhedzisela yo livhana na musaukanyo wa zwi re ngomu. U itela u ṋekedza na u saukanya mihumbulo ya vho dzhenelelaho ho topolwa thero dza ndeme, dzine khadzo ha vha na u timatima nga ha mushumo wa vhadededzi vha lavhelesaho kha nyito dza u funza, na zwithithisi zwa tshumiso ya nḓowenḓowe dza u funza.
Mawanwa o bvisela khagala uri tshifhinga tshipfufhi tsho ṋekedzwaho nḓowenḓowe dza u funza tsho ṋekedza khaedu khulwane maelana na ndeme ya vhugudisi vhune ha ṋekedzwa matshudeni a zwa vhudededzi. Masheleni a songo lingana a matheriaḽa wa u funza na u guda, na u shaya u bvela khagala na u tendelana kha mushumo wa vhadededzi vha lavhelesaho ndowenḓowe dza u funa, na zwone zwo vhigiwa. Musi vhunzhi ha mawaṅwa a ngudo a tshi elana na a mishumo ya u rangani, hu na mawanwa a kungaho a uri matshudeni vha zwa vhudededzi vho kona u sumbedzisa u ḓivha mafhungo a thero dzavho, fhedzi vha vha vha si na nḓivho yo linganaho ya zwikili, kha ngona dza u funza. Zwo ḓisendeka nga vhuṱanzi ho kuvhanganyiwaho na u saukanywa, muṱoḓisisi o wana uri nḓowenḓowe dza u funza dzine vhatelwadigirii vha Yunivesithi ya Zambia vha shumisa zwikoloni, a dzi tou shuma. Ngudo dzo khunyeledza uri hu vhe na themendelo dzo vhalaho dza u shandukisa nyimele ya zwithu, zwine zwa sia Tshikolo tsha zwa Pfunzo tshi tshi tea u fhandekanywa na miṅwe mihasho uri hu vhe na tshifhinga tshinzhi tsha vhugudisi na nḓowenḓowe dza u funza zwikoloni. / Curriculum and Instructional Studies / D. Phil. (Education)
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Grassroots Canadian Muslim Identity in the Prairie City of Winnipeg: A Case Study of 2nd and 1.5 Generation Canadian MuslimsHameed, Qamer January 2015 (has links)
What are grassroots “Canadian Muslims” and why not use the descriptor “Muslims in Canada”? This thesis examines the novel concept of locale specific grassroots Canadian Muslim identity of second and 1.5 generation Muslims in the prairie city of Winnipeg, Manitoba. The project focuses on a generation of Muslims that are settled, embedded, and active in a medium sized Canadian metropolis. Locale plays a powerful part in the way people navigate identities, form attachments, find belonging, and negotiate communities and society. In order to explore this unique identity a case study was conducted in Winnipeg. Interviews with 1.5 and second generation Muslims explored the experience of grassroots Canadian Muslim identity. The project does not focus on religious doxy or praxis but rather tries to understand a lived Canadian Muslim identity by exploring discourse and space as well as strategies, social perceptions and expectations. Participant observation, community resources and literature also aid in the understanding of the grassroots Canadian Muslim experience. This study found that the attachments, networks, and experiences in the locale give room for an embedded Canadian Muslim experience and more negotiable identities than most studies on Muslims in Canada describe. These individuals are not foreigners living in Canada. Their worldviews develop out of this particular and embedded grassroots experience. They navigate a new kind of hybrid Canadian Muslim identity that is unique and flexible. This is the Canadian Muslim experience of 2nd and 1.5 generation Winnipeg Muslims.
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Development and Evaluation of a Road Marking Recognition Algorithm implemented on Neuromorphic Hardware / Utveckling och utvärdering av en algoritm för att läsa av vägbanan, som implementeras på neuromorfisk hårdvaraBou Betran, Santiago January 2022 (has links)
Driving is one of the most common and preferred forms of transport used in our actual society. However, according to studies, it is also one of the most dangerous. One solution to increase safety on the road is applying technology to automate and prevent avoidable human errors. Nevertheless, despite the efforts to obtain reliable systems, we have yet to find a reliable and safe enough solution for solving autonomous driving. One of the reasons is that many drives are done in conditions far from the ideal, with variable lighting conditions and fast-paced, unpredictable environments. This project develops and evaluates an algorithm that takes the input of dynamic vision sensors (DVS) and runs on neuromorphic spiking neural networks (SNN) to obtain a robust road lane tracking system. We present quantitative and qualitative metrics that evaluate the performance of lane recognition in low light conditions against conventional algorithms. This project is motivated by the main advantages of neuromorphic vision sensors: recognizing a high dynamic range and allowing a high-speed image capture. Another improvement of this system is the computational speed and power efficiency that characterize neuromorphic hardware based on spiking neural networks. The results obtained show a similar accuracy of this new algorithm compared to previous implementations on conventional hardware platforms. Most importantly, it accomplishes the proposed task with lower latency and computing power requirements than previous algorithms. / Att köra bil är ett av de vanligaste och mest populära transportsätten i vårt samhälle. Enligt forskningen är det också ett av de farligaste. En lösning för att öka säkerheten på vägarna är att med teknikens hjälp automatisera bilkörningen och på så sätt förebygga misstag som beror på den mänskliga faktorn. Trots ansträngningarna för att få fram tillförlitliga system har man dock ännu inte hittat en tillräckligt tillförlitlig och säker lösning för självkörande bilar. En av orsakerna till det är att många körningar sker under förhållanden som är långt ifrån idealiska, med varierande ljusförhållanden och oförutsägbara miljöer i höga hastigheter. I det här projektet utvecklar och utvärderar vi en algoritm som tar emot indata från dynamiska synsensorer (Dynamic Vision Sensors, DVS) och kör datan på neuromorfiska pulserande neuronnät (Spiking Neural Networks, SNN) för att skapa ett robust system för att läsa av vägbanan. Vi presenterar en kvantitativ och kvalitativ utvärdering av hur väl systemet läser av körbanans linjer i svagt ljus, och jämför därefter resultaten med dem för tidigare algoritmer. Detta projekt motiveras av de viktigaste fördelarna med neuromorfiska synsensorer: brett dynamiskt omfång och hög bildtagningshastighet. En annan fördel hos detta system är den korta beräkningstiden och den energieffektivitet som kännetecknar neuromorfisk hårdvara baserad på pulserande neuronnät. De resultat som erhållits visar att den nya algoritmen har en liknande noggrannhet som tidigare algoritmer på traditionella hårdvaruplattformar. I jämförelse med den traditionella tekniken, utför algoritmen i den föreliggande studien sin uppgift med kortare latenstid och lägre krav på processorkraft. / La conducción es una de las formas de transporte más comunes y preferidas en la actualidad. Sin embargo, diferentes estudios muestran que también es una de las más peligrosas. Una solución para aumentar la seguridad en la carretera es aplicar la tecnología para automatizar y prevenir los evitables errores humanos. No obstante, a pesar de los esfuerzos por conseguir sistemas fiables, todavía no hemos encontrado una solución suficientemente fiable y segura para resolver este reto. Una de las razones es el entorno de la conducción, en situaciones que distan mucho de las ideales, con condiciones de iluminación variables y entornos rápidos e imprevisibles. Este proyecto desarrolla y evalúa un algoritmo que toma la entrada de sensores de visión dinámicos (DVS) y ejecuta su computación en redes neuronales neuromórficas (SNN) para obtener un sistema robusto de seguimiento de carriles en carretera. Presentamos métricas cuantitativas y cualitativas que evalúan el rendimiento del reconocimiento de carriles en condiciones de poca luz, frente a algoritmos convencionales. Este proyecto está motivado por la validación de las ventajas de los sensores de visión neuromórficos: el reconocimiento de un alto rango dinámico y la captura de imágenes de alta velocidad. Otra de las mejoras que se espera de este sistema es la velocidad de procesamiento y la eficiencia energética que caracterizan al hardware neuromórfico basado en redes neuronales de impulsos. Los resultados obtenidos muestran una precisión similar entre el nuevo algoritmo en comparación con implementaciones anteriores en plataformas convencionales. Y lo que es más importante, realiza la tarea propuesta con menor latencia y requisitos de potencia de cálculo.
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Fall Like a ManNorth, Naomi 20 April 2016 (has links)
No description available.
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