Detta arbete är en jämförande studie mellan mätningar inom användbarhet. Studien jämför en heuristisk utvärdering med ett användartest, med inriktning på ekonomi och resultat. Syftet är att belysa den ekonomiska aspekten mellan de två metoderna. Samtidigt undersöker studien om heuristisk utvärdering är en metod som lämpar sig som beslutsunderlag. Studien är genomförd på ett tryckeri där tryckeriets IT-system har testats och utvärderats utifrån de två metoderna. Studien baseras på kvalitativa och kvantitativa metoder så som strukturerade och ostrukturerade intervjuer, observationer och enkäter.Arbetet behandlar användbarhet som begrepp och metoder för hur användbarhet mäts. Relevant teori presenteras i teoridelen och behandlas i diskussionen. De båda metoderna var relativt lika varandra. Den stora skillnaden ligger i att användartestet gav mätbara resultat medan den heuristiska utvärderingen resulterade i en givande diskussion. Ur ett ekonomiskt perspektiv var den heuristiska utvärderingen betydligt billigare att genomföra. Undersökningen visar att den heuristiska utvärderingen fungerar bra. Dock bör metoden undersökas ytterligare för att styrka påståendet. / Resource-saving methods in usability This essay is a comparative study of measuring usability. The study compares a heuristic evaluation with a usability test, with focus on economy and performance. The aim is to highlight the economic aspect between the two methods, also if the study of heuristic evaluation is a method suitable for decision-making. The study is conducted on a printing company where the company’s IT systems have been tested and evaluated on the basis of the two methods. The study is based on qualitative and quantitative methods such as structured and unstructured interviews, observation and questionnaires.The study deals with usability as a concept and different methods for measuring usability. Relevant theory is presented in the theoretical part and is discussed and addressed in the discussion.Both methods were relatively similar. The major difference is that the user test yielded measurable results, while the heuristic evaluation resulted in a fruitful discussion. From a financial perspective, the heuristic evaluation is significantly cheaper to implement. The study shows that the heuristic evaluation works well. However, the method should be further investigated to prove the claim.

Recent research suggests that financial system development is important for economic development and for reducing financing constraints of firms (Levine, 2005). Consequently, researchers started investigating the factors that determine financial system development. A group of factors that have been identified are institutional factors. Many researchers have investigated the theoretical and empirical links among historical institutional factors, current institutional factors, and financial system development (Beck and Levine, 2005). There are, however, few studies that have investigated extensively the theoretical and empirical links among institutional factors and financial system development within the African context. Africa provides an interesting context to empirically validate and refine many of the theories that have been postulated to explain the relationships among historical and current institutional factors and financial system development. This is because Africa is in the process of developing its institutions and reforming existing ones and offers an opportunity to examine the impact of institutional factors on financial system development in nascent contexts. Therefore, this dissertation investigated the following research question: To what extent are institutional factors determinants of financial system development in Africa? To answer this research question, this study empirically evaluated the effects on financial system development of historical institutional factors that have been identified by four theories: legal origins theory, disease endowment theory, religion-based theory, and ethnic fractionalisation theory. Moreover, current institutional factors identified by the law and finance theory as possible determinants of financial system development were empirically examined. Furthermore, the links among historical and current institutional factors were empirically studied. The results show that the disease endowment variables are the only historical institutional factors that explain cross-country variation in financial system development in Africa. Additionally, this study finds that the institutional enforcement quality and efficiency of the judicial system are the only current institutional factors that explain cross-country variation in financial system development in Africa. Current institutional factors such as the efficiency of the legal property system and the quality of the credit information infrastructure do not appear to have effects on financial system development. Moreover, the institutional enforcement quality seems to be one of the possible channels through which disease endowment affects financial system development in Africa. This study also reveals that there are few statistically significant links among historical and current institutional factors within the African context. To my knowledge, this is the first study to show some of these empirical links among historical institutional factors, current institutional factors, and financial system development for the African context. The main conclusion of this dissertation is that institutional factors seem not to be determinants of financial system development in Africa to a large extent. In essence, institutional factors appear to matter for financial system development in Africa, but not as much as might have been expected judging from many calls for institutional reforms from the World Bank and others. The theoretical and policy implications of the findings of this dissertation are discussed, and future areas of research are also proposed.

目前資訊系統之建置多為求速成而以採購所謂解決方案的套裝系統或元件拼裝為主，雖然此舉帶來軟體再用效益使建置成本降低但由於實施過程抽象化不足使得欲讓系統適應用戶環境時客製化困難且各套裝系統詞彙標準不一也造成資料整合時語意混淆，導致空有外殼讓系統與組織扞格不入而無法帶來實質效益。本研究所提之系統發展方法即是為解決上述情況以本體論為概念描述基礎分從靜態資料觀點、動態流程觀點及資訊技術觀點出發進而彙整發展具彈性與再用性之資訊系統。 本研究過程是植基於設計科學的系統發展研究方法論，將資訊系統開發流程分為五個階段，並根據設計科學的定義，驗證研究結果的四項產出：構件、模型、方法與實例，希從學術的嚴謹面提昇產出結果的品質。並藉著探討分析運用本研究之發展方法建置出的個案，其所得到之結果足以供後繼者建置或改善知識管理相關系統做參考。 / In these few decades, many organizations pursued of e-Solutions by selecting so-call off-the-shelf packages or mixed 3rd party components to promote the reusing value and reduce the cost of implementation. However, there is no single solution suitable for all types of organization and customized or hybrid system must be inevitable to face the consistency problem. We believe the proper abstraction and ontological commitment can help in these situations. From this point of view, we propose the information system development methodology which is aiming to implement the flexible and reusable ontology driven information system from the view of static domain data, dynamic workflow and abstract technology. In this study, we conduct the system development research methodology based on design science. In order to easily note, we divide the research process into five stages. According to the criteria of design science, we will examine the research results: constructs, models, methods and instantiations for consolidating the quality of research outputs. Besides, we will show the cases which are implemented by proposed methodology for further study and suggestion of improving present system development issues.

This study investigated the use of systems development methodologies in Web-based application development in South Africa. Web-based systems differ from traditional information systems by integrating different media for knowledge representation and utilizing hypertext functionality. By doing this, Web-based systems not only support creation, integration, analysis, and distribution but also storage and transfer of knowledge of business transactions within a structured information system. There are numerous methodologies available to develop Web-based systems. In this study five of these methodologies were discussed. The methodologies include Web IS Development Methodology (WISOM), Internet Commerce Development Methodology (ICOM), Web Engineering, Extreme Programming and the Relationship Management Methodology (RMM). In this study a qualitative research approach was followed. Case studies were done on three different organizations in the South African marketplace. Semi-structured interviews were used for data collection at each organization. The interviews were transcribed, and the data were analysed using content analysis and cross-case analysis. One of the main goals of this research was to determine "how" system development methodologies are used in practice to develop Web-based systems, and to what extent it is used. The research pointed out that those organizations who participated in this study in South Africa mainly use in-house developed methodologies to develop Web-based systems, and that these organizations adhere strictly to their methodology. The main reasons organizations choose to use methodologies are that methodologies aid in the delivery of a better quality Web-based system, and also act as a good project management mechanism within the organization. / Thesis (M.Com. (Computer Science))--North-West University, Potchefstroom Campus, 2007

傳統 PC市場在歷經高速成長後，已逐漸歷經高原期而邁入衰退期。面對這個連上下游都競爭十分激烈的環境，所有PC品牌商都面臨生存保衛戰，只是基於各自不同的競爭力而往不同的方向調整。個案公司透過觀察上游作業平台所建構之生態系統找出一個有別於傳統價值鏈垂直上下游整合的零和方法。經由盤點自身的核心能力，配合外部策略機會，找出了有別於其他PC品牌商的策略定位。透過建立平台，架構有利於自己的生態系統，再透過併購，策略投資，策略聯盟，合組合資公司的方法將擁有關鍵核心能力的廠商整合進這個生態系統，強化生態系統的競爭力。在以此吸引更多具有關鍵核心能力的廠商加入，壯大生態系統，產生正向循環。透過打群架的方法與其他生態系統合作或對抗。如此將可協助企業快速獲得轉型所需要培養的人才與能力，爭取時間度過轉型期，邁向新的事業高峰。

Au long des dernières décennies, des importants avancements ont été réalisés dans le domaine de la reconnaissance de la parole à grand vocabulaire. Un des défis à relever dans le domaine concerne la réduction des coûts de développement nécessaires pour construire un nouveau système ou adapter un système existant à une nouvelle tâche, langue ou dialecte. Les systèmes de reconnaissance de la parole à l’état de l’art sont basés sur les principes de l’apprentissage statistique, utilisant l’information fournie par deux modèles stochastiques, un modèle acoustique (MA) et un modèle de langue (ML). Les méthodes standards utilisées pour construire ces modèles s’appuient sur deux hypothèses de base : les jeux de données d’apprentissage sont suffisamment grands, et les données d’apprentissage correspondent bien à la tâche cible. Il est bien connu qu’une partie importante des coûts de développement est dû à la préparation des corpora qui remplissent ces deux conditions, l’origine principale des coûts étant la transcription manuelle des données audio. De plus, pour certaines applications, notamment la reconnaissance des langues et dialectes dits "peu dotés", la collecte des données est en soi une mission difficile. Cette thèse a pour but d’examiner et de proposer des méthodes visant à réduire le besoin de transcriptions manuelles des données audio pour une tâche donnée. Deux axes de recherche ont été suivis. Dans un premier temps, des méthodes d’apprentissage dits "non-supervisées" sont explorées. Leur point commun est l’utilisation des transcriptions audio obtenues automatiquement à l’aide d’un système de reconnaissance existant. Des méthodes non-supervisées sont explorées pour la construction de trois des principales composantes des systèmes de reconnaissance. D’abord, une nouvelle méthode d’apprentissage non-supervisée des MAs est proposée : l’utilisation de plusieurs hypothèses de décodage (au lieu de la meilleure uniquement) conduit à des gains de performance substantiels par rapport à l’approche standard. L’approche non-supervisée est également étendue à l’estimation des paramètres du réseau de neurones (RN) utilisé pour l’extraction d’attributs acoustiques. Cette approche permet la construction des modèles acoustiques d’une façon totalement non-supervisée et conduit à des résultats compétitifs en comparaison avec des RNs estimés de façon supervisée. Finalement, des méthodes non-supervisées sont explorées pour l’estimation des MLs à repli (back-off ) standards et MLs neuronaux. Il est montré que l’apprentissage non-supervisée des MLs conduit à des gains de performance additifs (bien que petits) à ceux obtenus par l’apprentissage non-supervisée des MAs. Dans un deuxième temps, cette thèse propose l’utilisation de l’interpolation de modèles comme une alternative rapide et flexible pour la construction des MAs pour une tâche cible. Les modèles obtenus à partir d’interpolation se montrent plus performants que les modèles de base, notamment ceux estimés à échantillons regroupés ou ceux adaptés à la tâche cible. Il est montré que l’interpolation de modèles est particulièrement utile pour la reconnaissance des dialectes peu dotés. Quand la quantité de données d’apprentissage acoustiques du dialecte ciblé est petite (2 à 3 heures) ou même nulle, l’interpolation des modèles conduit à des gains de performances considérables par rapport aux méthodes standards. / One of the outstanding challenges in large vocabulary automatic speech recognition (ASR) is the reduction of development costs required to build a new recognition system or adapt an existing one to a new task, language or dialect. The state-of-the-art ASR systems are based on the principles of the statistical learning paradigm, using information provided by two stochastic models, an acoustic (AM) and a language (LM) model. The standard methods used to estimate the parameters of such models are founded on two main assumptions : the training data sets are large enough, and the training data match well the target task. It is well-known that a great part of system development costs is due to the construction of corpora that fulfill these requirements. In particular, manually transcribing the audio data is the most expensive and time-consuming endeavor. For some applications, such as the recognition of low resourced languages or dialects, finding and collecting data is also a hard (and expensive) task. As a means to lower the cost required for ASR system development, this thesis proposes and studies methods that aim to alleviate the need for manually transcribing audio data for a given target task. Two axes of research are explored. First, unsupervised training methods are explored in order to build three of the main components of ASR systems : the acoustic model, the multi-layer perceptron (MLP) used to extract acoustic features and the language model. The unsupervised training methods aim to estimate the model parameters using a large amount of automatically (and inaccurately) transcribed audio data, obtained thanks to an existing recognition system. A novel method for unsupervised AM training that copes well with the automatic audio transcripts is proposed : the use of multiple recognition hypotheses (rather than the best one) leads to consistent gains in performance over the standard approach. Unsupervised MLP training is proposed as an alternative to build efficient acoustic models in a fully unsupervised way. Compared to cross-lingual MLPs trained in a supervised manner, the unsupervised MLP leads to competitive performance levels even if trained on only about half of the data amount. Unsupervised LM training approaches are proposed to estimate standard back-off n-gram and neural network language models. It is shown that unsupervised LM training leads to additive gains in performance on top of unsupervised AM training. Second, this thesis proposes the use of model interpolation as a rapid and flexible way to build task specific acoustic models. In reported experiments, models obtained via interpolation outperform the baseline pooled models and equivalent maximum a posteriori (MAP) adapted models. Interpolation proves to be especially useful for low resourced dialect ASR. When only a few (2 to 3 hours) or no acoustic data truly matching the target dialect are available for AM training, model interpolation leads to substantial performance gains compared to the standard training methods.

O início da neurogênese e diferenciação neural no sistema nervoso do embrião é controlado pela expressão orquestrada de fatores de transcrição. A caracterização de novos reguladores transcricionais nestes processos é importante para o entendimento dos mecanismos responsáveis pela formação de neurônios. Neste trabalho, nós investigamos a função do fator de transcrição Scrt2 na medula espinhal do embrião de galinha. Nossos resultados indicam que Scrt2 é expresso imediatamente após a saída do ciclo celular e em conjunto com Ngn2 e NeuroM, sugerindo uma função em neurônios recém-nascidos. Para identificar potenciais alvos de Scrt2, realizamos experimentos de eletroporação in ovo no tubo neural posterior e analisamos os fenótipos transcriptômicos com RNA-Seq. Por fim, apresentamos também uma caracterização do transcriptoma do tubo neural posterior selvagem entre HH18 e HH29 (E6), provendo uma extensa base de dados de expressão gênica para futuras investigações. Com base em nossa experiência, nós discutimos o uso de RNA-Seq em diferentes abordagens experimentais. / The onset of neurogenesis and neural differentiation in the embryonic nervous system is controlled by the coordinated expression of transcription factors. Identification of novel transcriptional regulators in these processes is essential for our understanding of the mechanisms underlying neuronal differentiation. Here, we used the chick embryonic spinal cord to investigate the role of the transcription factor Scrt2. Our results indicate that Scrt2 is expressed in cells that recently exited the mitotic cycle and overlaps with Ngn2 and NeuroM, suggesting a function in newborn neurons. To identify potential gene targets of Scrt2, we performed in ovo electroporation experiments in the posterior neural tube and assessed the transcriptomic phenotypes using RNA-Seq. Finally, we also present the transcriptomic profiles of the wild-type posterior neural tube from HH18 to HH29 (E6), providing an informative gene expression database for future investigations. Based on our experience, we discuss the use of RNA-Seq in distinct experimental approaches.

The brain is a highly complex structure; neurons extend axons which follow precise paths to make connections with their targets. This extension is guided by a specialised and highly motile structure at the axon tip -the growth cone- which integrates guidance cues to steer the axon through the environment. Aberrant pathfinding is likely to result in developmental impairments causing disruption to brain functions underlying emotion learning and memory. Furthermore, pre-existing connections are constantly remodelled, the ability to do so declines with age, and can have huge impacts on quality of life and well-being. Examining how changes in growth cone behaviour triggered by external cues occurs is crucial for understanding processes in both development and disease. Controlled reorganisation of growth cone cytoskeletal components, such as actin filaments, generate membrane protrusions forming lamellipodia and filopodia. Filopodium formation is commonly associated with sensing the mechanical and chemical environment of the cell. Despite our understanding of the guidance choices that can be made, how filopodia transmit information at a molecular level leading to profound changes in morphology, motility and directionality remains largely unknown. Various actin-binding proteins regulate the number, stability and branching of filopodia. They may therefore have a key role in priming or abrogating the ability of the growth cone to respond to a given guidance cue. I have shown that the actin binding proteins drebrin and cofilin, whilst displaying opposing molecular activities on actin filaments, work synergistically in a temporally regulated manner. A fluorescent membrane marker combined with tagged cofilin and drebrin enabled accurate correlation of cofilin and drebrin dynamics with growth cone morphology and filopodial turnover in live neurons. In contrast to previous in vitro experiments, cofilin was found to enhance the effect of drebrin to promote filopodia formation in intact neurons, and that growth cone spread was significantly constrained when cofilin was knocked down. Importantly, this adds to our understanding of how the two actin binding proteins contribute to directed motility in neuronal growth cone filopodia during guidance. Furthermore, following acute treatment with low concentrations of the repulsive guidance cue semaphorin-3A, neuronal growth cones expressing cofilin displayed increased morphological complexity and filopodial stability. This suggests that traditional collapse signals may serve as pause signals allowing neurons to increase the surface area to sense the environment adequately and enable precise wiring decisions. Remodeling of the cytoskeleton is perturbed in a number of degenerative diseases including Alzheimer's, Huntington's, and Amyotrophic Lateral Sclerosis. These conditions are associated with widespread synaptic loss, resulting in memory loss, cognitive impairment, and movement disorders which leads to severe deterioration in quality of life for those afflicted in addition to wider negative socioeconomic impacts. How widespread synaptic loss occurs is poorly understood. One common characteristic is neuronal stress which can be initiated through different conditions such as neuroinflammation, energetic stress, glutamate excitotoxicity, and accumulation of misfolded proteins, all of which have been associated with perturbation of the actin cytoskeleton and the initiation of the cofilin-actin rod stress response. Dysfunction of the cytoskeleton can lead to the disruption of synaptic activity by blocking the delivery of elements such as organelles and proteins required for maintenance of the synapse. Modulating this stress response offers an approach to protecting the integrity of normal synaptic function. Actin interacting protein-1 is a conserved actin binding protein that enhances the filament disassembly activity of cofilin. I have discovered that AIP-1 has a potent ability to prevent the formation of cofilin rods which are thought to contribute to the neuronal dysfunction in several neurodegenerative disorders, even when they are treated with amyloid-β or subjected to metabolic stress. This is the first study to demonstrate a molecular mechanism for preventing rod formation in the presence of a neuronal stressor and has the potential to protect against rod formation by other stressors associated with disease such as inflammation and excitotoxicity. AIP-1 offers the exciting possibility of a means to reverse cofilin rod formation and the subsequent cytoskeletal pathology associated with dementia and has potential for therapeutic exploitation in human disease. Furthermore, it is the first study to demonstrate that AIP-1 localises to areas of rapid actin remodeling in neuronal growth cones. Exploiting the action of AIP-1 therefore represents an exciting and novel therapeutic avenue to tackle neurodegeneration.

Nesta tese, dois projetos distintos que usaram a técnica do Espalhamento de Luz foram desenvolvidos. Estudou-se a influência de soluções concentradas de uréia sobre agregados supramoleculares de anfifilicos (ASA\'s), através de condutimetria, supressão de fluorescência e espalhamento de luz. A uréia causou aumento da concentração micelar crítica (CMC) em todos os sistemas micelares estudados. A uréia diminuiu a seletividade da ligação iônica entre cloreto e brometo em micelas de haleto de cetil-trimetil-amônio, estudada através de supressão de fluorescência. Este aditivo causou também aumento na segunda CMC de brometo de tetradeciltrimetil- amônio (TTAB) e diminuição do peso molecular das micelas em bastão formadas. Concluiu-se, desta primeira parte, que a uréia tende a interferir nas transições de fase apresentadas em sistemas micelares, provavelmente através da combinação dos mecanismos direto e indireto. A uréia apresenta potencial para uso como aditivo para modulação das propriedades estruturais de sistemas micelares. Na segunda parte da tese desenvolveu-se um sistema, baseado em espalhamento de luz, capaz de monitorar o peso molecular de polímeros durante a polimerização. O sistema foi eficiente no monitoramento da polimerização da N-vinil-pirrolidinona, mostrando que o peso molecular do polímero formado é constante durante a maior parte da reação. As teorias atuais de cinética de polimerização não foram capazes de explicar esse comportamento. / Light scattering techniques (static and dynamic) were used to detenninate the effect of urea on supramolecular aggregates and to monitor on-line molar mass ofpolymerization reactions. For the first set of investigation it was already established that urea increases the CMC and the dissociation degree (α) of ionic micelles (CTABr, TTABr, and SDS). From fluorescence suppression studies it was found that urea diminishes the ionic binding in zwitterionic and cationic micelles as well as in cationic vesicles. Bromide and chloride ionic selectivity in cationic micelles was found to nearly disappear in the presence of urea. Light scattering (static) detenninations showed that the weight averaged molecular weight (Mw) ofboth SDS and CTABr are invariant by the presence of the denaturant. A slight increase in the excluded volume tenn (A2) was detected for CTABr in the presence of 3M urea. In parallel both A2 and the radius of gyration (γ) of two polyelectrolytes (PAA and Hyaluronic acid) were not affected by the presence of urea. Sphere-to-rod concentration transitions (2nd CMC) of TIABr micelles increased in the presence of urea and the MW of rod particles were observed to decrease. For the insoluble mixture of CTABr/Polystyrenesulfonate solubilization was achieved in the presence of 3M urea. These set of results were explained as a result of the dual effect of urea, that is, the indirect effect by changing the properties of the solvent and the direct effect by solvating the hydrophilic domain of the aggregates and contributing with a stronger dipole moment. The second set of experiments was directed towards the real-time, on-line monitoring of Mw of polymerization reactions. This new approach could be succeeded by the coupling a light scattering detector, an UV photometer and a differential refractometer on line with a HPLC system. Mw growth formed in the polymerization of N-vynil-pirrolidone was accomplished with a small inherent error. Within the studied conditions Mw reached a plateau at early polymerization stages, after that only an increase in the number of polymer kinetic chains was observed. Current kinetic models were unable to predict the observed Mw growth pattern. This system is of great importance in basic and technological applications by virtue of its on-line capability.

應用系統的發展從以前的部門資訊系統，到目前的企業整體資源規劃系統(Enterprise Resource Planning, ERP)，更而甚之地橫跨企業組織的供應鏈管理系統(Supply Chain Management, SCM)；從這樣的趨勢發展我們可以輕易地發現應用系統的範圍逐漸擴大，而且對系統品質及穩定度的要求越來越高，因此也讓軟體從業人員面臨了三大挑戰：系統複雜度提高、開發效率的提升及系統品質的確保。 1997年物件管理委員會(Object Management Group, OMG)通過了統一化塑模語言(Unified Modeling Language, UML)成為物件導向塑模語言的標準之後，物件導向開發方法開始被軟體從業人員所重視。 雖然物件導向系統發展方法從分析到設計階段能有效地讓系統具有低耦合力(low coupling)及高內聚力(high cohesion)之特性，而且企業應用框架(Business Framework)在系統設計到實作、測試及維護階段能夠以其標準化的企業物件、系統開發方式及彈性化的架構讓整體成本下降。然而企業應用框架的提供廠商通常欠缺著一套結合了物件導向分析與設計和企業應用框架的系統發展方法，因此本研究的目的在於透過對物件導向塑模語言、軟體工程及專案管理和企業應用框架的研究與了解，試圖將企業應用框架與UML及Unified Process結合，以彙整出一套系統發展指引，稱為以框架為基礎之元件化系統發展方法(Framework-based Componentized System development Process)，以期有效提升軟體的生產力及品質，成為下一代開發應用系統的方法。