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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
601

Development of an Interactive E-learning Management System (e-LMS) for Tanzanian Secondary Schools

Kalinga, Ellen January 2010 (has links)
e-Learning, defined as the use of information and communications technology (ICT) for supporting the educational process, has motivated Tanzania to apply ICT in its education systems. Tanzanian secondary schools which are geographically and socially isolated face a number of problems, including a way to get learning materials. The impact of these problems is poor performance in National Examinations. This poor performance however is most noted in science and mathematics. The problem in get- ting learning materials can be reduced by employing ICT. This research developed an interactive e-learning management system (e-LMS) to be used by Tanzanian secondary schools. Tanzania Secondary Schools e-Learning (TanSSe-L) system is the name adopted for an interactive e-LMS developed. The re- search is aimed at supporting teaching and learning functions by allowing for the creation and storage of learning materials, making them available, easily accessed and sharable by students from different secondary schools in Tanzania. It is a context- driven research work of knowledge production in a specific context for application. Initially, the research work focused on two selected pilot schools; Kibaha Secondary School and Wali-ul-Asr Girls’ Seminary in Kibaha town, Pwani region. Features of the TanSSe-L system represent the standard form of any secondary school registered by the Ministry of Education and Vocational Training. The development of the TanSSe-L system made use of software engineering discipline. The research used Unified Modelling Language (UML) and integrated Object-Orient- ed System Analysis and Design (OOSA&D) and Model Driven Architecture (MDA) to address the System Development Life Cycle (SLDC) in a systemic way. UML design class diagram (DCD) is a Platform Independent Model (PIM) that was transformed into a Platform Specific Model (PSM) in MDA for implementation. Implementation made use of open source LMS to help generate a timely solution to TanSSe-L system development. In this specific context, focus group discussion as inspired by action re- search methodology was used. The research evolved into a triple helix process in close cooperation with other stakeholders. Finally, it is considered that replication and mirroring will make learning materials highly available to end-users.
602

Development of E-learning Content and Delivery for Self Learning Environment : Case of Selected Rural Secondary Schools in Tanzania

Lujara, Suzan January 2010 (has links)
The effective use of Information and Communications Technology (ICT) in devel-oping countries like Tanzania is crucial in order to overcome the challenges that are faced countrywide in many sectors, and to reduce the digital divide and improve the economy. ICT is becoming more and more integrated in societies worldwide, its effects are clearly seen in people’s lives as well as on countries’ economy as it opens doors for new opportunities and change the attitude of people towards learning. Secondary schools in Tanzania are facing many problems which hamper students’ learning. This in turn affects their performance in the National examinations hence reducing the growth of a learned society. This research specifically addresses the prob- lem of lack of learning and teaching materials by using ICT tools for the development and delivery of e-Learning content. The research focused on two secondary schools, namely, the Wali-Ul-Asr Seminary and Kibaha Secondary School as pilot schools in Kibaha district Pwani region. The research used courseware engineering methodology which integrated instructional design and software engineering. The research was also inspired by the concepts of participatory action research, Mode 2 knowledge production and triple helix, which incorporated stakeholders’ participation throughout the research. The main stakeholders are researchers, students, teachers, head teachers, and Ministry of Education and Vocational Training officials. This is an applied type of research addressing a practical problem in society. The out- come is a pilot package of e-Learning material comprised of sample chapters of Mathematics form III at the pilot site. Blended mode of delivery has been considered using Compact Disc/Digital Versatile Disc Read Only Memory, the Tanzania Secondary Schools e-Learning (TanSS-L) System, a customized Moodle platform and by using face to face learning.
603

Etude des propriétés magnétiques des sédiments non consolidés : anisotropie et erreurs d'inclinaison paléomagnétique

Collombat, Héléne 09 February 1993 (has links) (PDF)
L'acquisition de l'aimantation dans les sédiments est régit par une somme de processus complexes et souvent interactifs, pouvant introduire des biais directionnels lors de la reconstitution du signal géomagnétique, en particulier des erreurs d'inclinaison. De telles erreurs peuvent mettre en doute l'utilisation de la paléovariation séculaire présumée du champs géomagnétique, révélée par l'ARN des sédiments. Les phénomènes à l'origine de ces erreurs sont principalement liées aux processus de dépôt des particules magnétiques et/ou à la compaction. Ces phénomènes affectent parallèlement la fabrique du sédiment et son anisotropie magnétique. Grâce à l'utilisation de l'anisotropie de susceptibilité anhystérétique (ASA). couplée à la technique plus classique d'anisotropie de susceptibilité magnétique (ASM), une méthode de détection et de correction des erreurs d'inclinaison a été mise au point. L'étude a porté sur un certain nombre de carottes océaniques et continentales présentant des anomalies d'inclinaisons de l'aimantation rémanente naturelle par rapport à la valeur attendue du champ géomagnétique. Des études de minéralogie magnétique ainsi qu'une technique expérimentale de resédimentation sous champ a permis d'estimer les rôles respectifs des propriétés intrinsèques au sédiment (nature, taille, et forme des particules magnétiques) et des influences perturbatrices extérieures (bioturbation, taux de sédimentation, etc ... ) sur l'acquisition de la fabrique et la création des erreurs d'inclinaison de l'ARN. Par ailleurs, l'utilisation de l'ASM sur des sédiments déformés provenant de la région du point triple du Chili a permis de détecter les directions des axes principaux de la déformation. L'origine et l'évolution de l'anisotropie sont discutées en fonction du contexte géodynamique régional.
604

Étude de complexes ribonucléoprotéiques impliqués dans la régulation de l'expression des protéines au cours de l'initiation de la traduction

Ménade, Marie 18 September 2007 (has links) (PDF)
L'expression génique est régulée à de nombreuses étapes de la vie cellulaire. La synthèse des protéines ou traduction, étape ultime de cette expression, est finement régulée. Elle comporte trois phases: l'initiation, l'élongation et la terminaison. L'initiation commence par l'établissement de la sous-unité ribosomique 40S sur cet ARNm qu'elle balaye ensuite jusqu'au codon initiation. Pour cela, des facteurs canoniques sont impliqués. Parmi eux, le facteur eIF3 interagit directement avec celle-ci. Au cours de mes travaux, j'ai étudié dans une première partie l'interaction putative entre le facteur eIF3 et la petite sous-unité ribosomique 40S. Le ribosome est constitué par deux types d'entités : des protéines ribosomiques et l'ARNr. Le facteur eIF3, contient au moins 13 sous-unités, dont deux possèdent un RRM, et sont potentiellement capables de lier cet ARNr via leur RRM: p44 et p116. eIF3p44 a montré auparavant qu'elle pouvait lier l'ARNr 18S. J'ai effectué un criblage d'une banque de fragments de cet ARNr pour identifier un site de liaison de p44 sur la sous-unité 40S. Les ARNm néo-synthétisés sont transportés et localisés afin de permettre l'expression des protéines au moment opportun et en un lieu précis de la cellule. Dans une deuxième partie, j'ai étudié des interactions impliquées dans le contrôle de l'initiation de la traduction d'un ARNm localisé chez la levure S. cerevisiae pendant son transport : l'ARNm ASH1. Il est régulé par Khd1p, protéine à trois domaines KH, qui lie directement un de ses éléments de localisation. Cette interaction est abolie par la phosphorylation de Khd1p lorsque l'ARNm est correctement localisé.
605

下一代網路資訊服務與系統供應商之成功經營模式研究

陳建宏, Chen, Chien Hung Unknown Date (has links)
下一代網路(Next Generation Network,NGN)是因應未來語音、數據、影像等Triple Play之資訊服務對頻寬與網路能力要求日益增加下所提出的一種新網路形態概念。同時,NGN以IP 多媒體子系統(IP Multimedia Subsystem,IMS)為其核心可以降低系統供應商的營運佈建成本。NGN強調的固網行動融合(Fixed Mobile Convergence,FMC)與全IP網路(All IP Network)化以及強化服務品質(Quality of Service,QoS)精神,都使資訊服務與系統供應業者需要思考出一套新的經營模式(Business Model),使其能在NGN上獲利。本研究之主要目的為以NGN的架構與特性為出發,剖析此一網路的數位匯流趨勢與其成功經營模式研究。 本研究採個案研究法(Case Study Method),透過次級資料的蒐集以及與本研究有關之文獻探討的方式,找出未來NGN的經營模式形貌,並透過訪談相關業者來佐證本研究所提出經營模式之合理性。 由於資訊服務產業範圍廣泛,故本研究選定VoIP及IPTV為主要研究對象,期盼能找出一套適合在NGN上獲利的模式。另外針對企業用戶,NGN也能協助企業增加競爭力,在商業情報的取得、溝通成本的降低、資訊管理系統等都能有所貢獻。 / Next Generation Network,NGN, is a new form of internet concept of Triple play informational service integrated voice mail, data and video as the requirements of more wider bandwidth and high internet power increase. Meanwhile, The core of IP Multimedia Subsystem,IMS, NGN targets can lower operational cost to system suppliers. NGN emphasizes the spirit to combine Fixed Mobile Convergence,FMC, all IP network and Enhanced Quality of Service. The spirit makes the suppliers of informational service and system to think a new business model to make profits in NGN. The research of this thesis bases on NGN’s structure and features to analyze the trend of digital convergence in internet and succeeded business model. This essay adopts Case Study Research. By collecting sub data and relative document research figures out future image of NGN business model. Besides, it is interviewed with pertaining businesses to testify the reality of business model offered in this thesis. Owning to the scope of informational service business is unlimited, the thesis is chosen VoIP and IPTV as main targets to find out an appropriate and a profitable business model in this informational field. Furthermore, to business user, NGN can support industries to increase competitive ability and gain useful business information, decrease communicative cost and upgrade the performance of MIS
606

The Development of a Coupled Physics and Kinetics Model to Computationally Predict the Powder to Power Performance of Solid Oxide Fuel Cell Anode Microstructures

Gaweł, Duncan Albert Wojciech 03 October 2013 (has links)
A numerical model was developed to evaluate the performance of detailed solid oxide fuel cell (SOFC) anode microstructures obtained from experimental reconstruction techniques or generated from synthetic computational techniques. The model is also capable of identifying the linear triple phase boundary (TPB) reaction sites and evaluating the effective transport within the detailed structures, allowing a comparison between the structural properties and performance to be conducted. To simulate the cell performance, a novel numerical coupling technique was developed in OpenFOAM and validated. The computational grid type and mesh properties were also evaluated to establish appropriate mesh resolutions to employ when studying the performance. The performance of a baseline synthetic electrode structure was evaluated using the model and under the applied conditions it was observed that the ionic potential had the largest influence over the performance. The model was used in conjunction with a computational synthetic electrode manufacturing algorithm to conduct a numerical powder to power parametric study investigating the effects of the manufacturing properties on the performance. An improvement in the overall performance was observed in structures which maximized the number of reaction sites and had well established transport networks in the ion phase. From the manufacturing parameters studied a performance increase was observed in structures with low porosity and ionic solid volume fractions near the percolation threshold, and when the anodes were manufactured from small monosized particles or binary mixtures comprising of smaller oxygen ion conductive particles. Insight into the anode thickness was also provided and it was observed that the current distribution within the anode was a function of the applied overpotential and an increase in the overpotential resulted in the majority of the current production to increase and shift closer to the electrode-electrolyte interface. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2013-10-01 09:41:47.617
607

The sustainability of donor funded projects in the health sector / T. Mitchell

Mitchell, Therese January 2013 (has links)
The need for donor funding has increased significantly over the last decade. Without donor funding millions of people wouldn’t be alive today. Thanks either to research finding a cure, successful treatment, funds donated for food, aid toward building infrastructure, or giving people the opportunity to further their education. Donor funding thus facilitates a better future. A literature review was conducted to give background on the health sector and how these funds were distributed, ethical clearance, different types of reporting, the role project managers pays in a project and the sustainability of projects. Expenses in different countries were evaluated by gathering data from the internet, while two international funded projects are also used to state how funders divide their line items into different categories. The empirical study used a qualitative research approach by collecting and analysing data obtained from the MDG 2010 report and other freely available data on the web. The main findings from this thesis are: *The Millennium Development Goals (MDG’s) influence donor funding as it gives donors a guide towards funding needs. Donors are also influenced by their own preferences or what poses a burden to them individually. *The different types of reporting required for funding received, delay a project and the bureaucratic structures thereof are a hindrance. *Ethical clearance plays a fundamental role in the outcome of a project, as without ethical clearance a project cannot commence. *The objectives of a project play a critical role when applying for funding. This can change the focus of a project. *Expenses differ from country to country and funders need to take this into account when giving funding to recipient countries. *Project Managers and community involvement plays a critical role in ensuring sustainability of projects. THE SUSTAINABILITY OF DONOR FUNDED PROJECTS IN THE HEALTH SECTOR *The MDG’s are not on track and aid are focus on singular goals instead of multiple goals, to ensure an overall improved result. There is a major gap between needed funds and given funds. A single injection of funds will not be the solution to our health problem; different sectors need to collaborate together as we are facing a multi-dimensional problem. Trade and reform must also form part of this aid, ensuring a sustainable progression in the life’s of people. Donor funded projects may have a sustainable future, when taking in account the abovementioned findings. With the world trend in reporting changing rapidly, cost and management accountants as well as financial accountants and project managers have to equip them to adhere to the new way of reporting, namely integrated and sustainability reporting. South Africa is way behind and needs to catch up fast if they want to stay competitive in the “global donor funding market”. The limitations in this study were that not all expenses were evaluated and only 15 countries were looked at. An indebt look was taken into Africa with the empirical review, while Asia is also combating poor health issues. Some African countries like Sierra Leone and Zimbabwe did not have sufficient data to compare with other countries. From the research conducted, the following topics were identified that require further research: *Why are most projects in Third World countries not sustainable? *What plans are put into action to ensure that the MDG goals are reached? *Investigate what works for First World countries health systems and consider how that can be applied to Third World countries to ensure that they also get the best health care available. *Do donors take into account the different costs of countries when allocating funding to that specific country? *Establishing models to evaluate the sustainability of pilot projects and normal projects. *Establishing a model on how to distribute donor funds across different needs and not only one specific need. / MCom (Management Accountancy), North-West University, Vaal Triangle Campus, 2013
608

Approche multiéchelle pour le comportement vibratoire des structures avec un défaut de rigidité

Ben Brahim, Nadia 13 June 2014 (has links) (PDF)
Nous considérons un système mécanique en vibration non linéaire, pour lequel nous fournissons une solution approchée par l'utilisation des développements multiples échelles; nous proposons d'abord une étude avec double échelles puis avec triple échelles où nous comparons les deux approches. Une preuve rigoureuse de ces développements a été faite. L'étude de la stabilité de la solution est nécessaire pour montrer la convergence au voisinage de la résonance. Un lien entre l'amplitude de la réponse vibratoire et la fréquence du système en vibration libre a été mis en évidence.
609

Facteurs prédictifs de mutation germinale BRCA1 dans le cancer du sein héréditaire / Prediction of BRCA1 germline mutation status in patients with breast cancer using histoprognosis grade, MS110, Lys27H3, Vimentin and KI67

Hassanein, Mohamed 16 December 2010 (has links)
En France, le cancer de sein héréditaire représente environ 2500 nouveaux cas par an, dont prés de la moitié est attribuée à la mutation du gène BRCA1.La recherche de la mutation par biologie moléculaire est un travail fastidieux, coûteux et long (8 mois d’attente environ actuellement).Pour trouver une solution à ce délai, nous avons étudié en immunohistochimie une série initiale de 21 anticorps répartis en 5 groupes : anticorps antiBrca1 du commerce, liés à la perte de l’inactivation de l’X, liés à la signature basale ou myoépithéliale, anticorps dits classiques du cancer de sein et finalement dérivés de signatures établies par cDNAarray.Nous avons utilisé la technique de’ tissue microarrays’ en utilisant de manière comparative une population de 27 cas de cancer de sein présentant une mutation germinale de BRCA1, et 81 cas témoins de cancer de sein sporadiques appariés à l’âge, ainsi qu’à des lignées cellulaires d’origine mammaires. Dans une deuxième série indépendante de validation nous avons appliqué les résultats obtenus de la première série sur 28 cas de cancer mammaire muté, et 28 cas du cancer mammaire sporadique dans les mêmes conditions initiales.Nos résultats montrent pour la première fois sur des tissus tumoraux une probabilité forte d’une association entre la mutation Brca1 et la perte de l’inactivation de l’X ; confirment la valeur de MS110 comme un bon anticorps prédictif d’une mutation de Brca1 ; apportent un argument pour une participation myoépithéliale dans l’oncogenèse de cancer mammaire Brca1 muté; appuient la relation entre ce dernier et les récepteurs RE,RP ainsi que P53 , Bcl2,Ki67 et valident en protéomique la valeur discriminant de CDC47 correspondant à un des gènes de la signature génomique.Après confirmation des mêmes résultats dans la série de validation, nous soutenons en analyses multivariés un modèle qui comprend seulement Grade 3, MS110, Lys27H3 négative, Vimentine et KI67 positive. Cette équation correspond à une sensibilité de 82% et spécificité de 81% et propose une approche rapide économique de pré- ciblage de la mutation Brca1 ; ce qui améliorait la prise en charge préventive, thérapeutique et globale des patients et leurs familles. / Family structure, lack of reliable information, cost and delay are usual concerns faced with when deciding to perform BRCA analyses. Testing the breast cancer tissues with four antibodies (MS110, lys27H3, Vimentin, KI67) in addition to grade evaluation enabled to rapidly select patients to carry out genetic testing identification. We constituted an initial breast cancer tissue micro-array, considered as a learning set comprising 27 BRCA1 and 81 sporadic tumours. A second independent validation set of 28 BRCA1 tumours was matched to 28 sporadic tumours using the same original conditions.We have investigated morphological parameters and 21 markers by immunohistochemistry.A logistic regression model was used to select the minimal number of markers providing the best model to predict BRCA1 status. The model was applied to the validation set to estimate specificity and sensibility.In the initial set, the univariate analysis identified 11 markers significantly associated with BRCA1 status. Then the best multivariate model comprised only Grade 3, MS110, Lys27H3, Vimentin and KI67. When applied to the validation set, BRCA1 tumours were correctly classified with a sensitivity of 83% and a specificity of 81%. The performance of this model was superior when compared to other profiles.This work offers a new rapid and economic method for the pre-screening of patients at high risk of being BRCA1mutation carriers, then to guide genetic testing, and finally to provide appropriate preventive measure, advices and treatments including targeted therapy to patients and their families.
610

Exploring Prospective Entrepreneurial Engagement and Stakeholders’ Involvement in the Circular Economy : An Empirical Study on the Concept of Växjö Reuse Village

Huang, Bin, Plas, Loukas, Salam, Nader January 2016 (has links)
During the search for a thesis topic, the researchers established contact with a civil servant at Växjö Municipality in Sweden who introduced them to the prospective project of the Reuse Village as part of the city’s waste management plan to enhance circular economy. Hence, the researchers’ purpose for this thesis is to explore the determined values and stakeholders’ involvement linked to the engagement of entrepreneurs towards a circular economy. Moreover, a thorough explanation of the literature review is conducted including the environmental, economic and social sustainability, in addition to the entrepreneurial and stakeholders’ involvement and the different sustainable oriented entrepreneurs and the values that could possibly influence the entrepreneurs. The researchers used mixed research methods that comprise of qualitative interviews, secondary research, and case studies based on documentary secondary data to give a deeper explanation of the stakeholders and entrepreneurial involvement and show their position in the field of circular economy especially in the Reuse Village project. The main findings of the thesis elaborate more on the importance of circular economy that governments and local municipalities are pushing for. The outcome presents the directions that stakeholders lean towards, regarding the Reuse Village, and shows how the relationship between the stakeholders plays a major role in the progress of the notion of circular economy.

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