The importance of evaluating the usability of e-commerce websites is well recognised and this area has attracted research attention for more than a decade. Nearly all the studies that evaluated the usability of e-commerce websites employed either user-based (i.e. user testing) or evaluator-based (i.e. heuristic evaluation) usability evaluation methods; but no research has employed softwarebased (i.e. Google Analytics software) in the evaluation of such sites. Furthermore, the studies which employed user testing and/or heuristic evaluation methods in the evaluation of the usability of e-commerce websites did not offer detail about the benefits and drawbacks of these methods with respect to the identification of specific types of usability problems. This research developed a methodological framework for the usability evaluation of e-commerce websites which involved user testing and heuristic evaluation methods together with Google Analytics software. The framework was developed by comparing the benefits and drawbacks of these methods in terms of the specific areas of usability problems that they could or could not identify on ecommerce websites. The framework involves Google Analytics software as a preliminary step to provide a quick, easy and cheap indication of general potential usability problem areas on an e-commerce website and its specific pages. Then, the framework enables evaluators to choose other methods to provide in-depth detail about specific iv problems on the site. For instance, the framework suggests that user testing is good for identifying specific major usability problems related to four areas: navigation, design, the purchasing process and accessibility and customer service, while the heuristic evaluation is good for identifying a large number of specific minor usability problems related to eight areas including: navigation, internal search, the site architecture, the content, the design, accessibility and customer service, inconsistency and missing capabilities. The framework also suggests that the heuristic evaluation is good at identifying major security and privacy problems. The framework was developed based on an extensive evaluation of the effectiveness of the three methods in identifying specific usability problems in three case studies (e-commerce websites) in Jordan. This highlighted the usefulness of the methods and therefore helps e-commerce retailers to determine the usability method that best matches their needs. The framework was tested and the results indicated the usefulness of the suggested framework in raising awareness of usability and usability evaluation methods among e-commerce retailers in Jordan. This will help them address usability in the design of their websites, thus helping them to survive, grow and achieve success.

Call number: LD2668 .T4 1986 Y362 / Master of Science / Civil Engineering

No description available.

This work studies guided wave propagation in pipes coated with thick highly viscoelastic coating materials. The main motivation for this study is the problems associated with Long Range Ultrasonic Testing (LRUT) of coated pipelines. The results reported in the literature show that the proper determination of the optimum LRUT parameters depends strongly on the bulk acoustic properties of the coating materials. The bulk acoustic properties of coating materials reported in the literature show that they could vary significantly depending on the coating material age, temperature and bonding level. The methods for acoustic characterisation of coating materials reported by other researchers, have been studied and it was found that they do not take into account the temperature changes and bonding level variation. In this work, the bulk acoustic properties of two highly viscoelastic bitumen based coating materials are investigated. The conventional methods for acoustic characterisation are studied and a new method for independent measurement of bulk shear properties of bitumen is developed. The bulk acoustic properties of bitumen based coating materials are also studied by two new characterisation methods. The first method derives the bulk coating material properties from experimental data on guided wave reflection coefficients. The second method derives the coating material bulk properties from experimentally measured guided wave attenuation data. It is demonstrated that these new methods deliver much more accurate values for the bulk acoustic properties when compared to the data measured by conventional methods. The second method is used to study the temperature effect on the bulk acoustic properties and it is demonstrated that temperature has a significant effect. The validity of the acoustic properties for the two bitumen materials is investigated through comparison between numerical predictions and experimental data measured for guided wave reflection coefficients and attenuation of the torsional T(0,1) and longitudinal L(0,2) guided wave modes. Good agreement is achieved in the frequency range between 20 kHz and 100 kHz, which is typical for LRUT of pipes.

abstract: The autonomous vehicle technology has come a long way, but currently, there are no companies that are able to offer fully autonomous ride in any conditions, on any road without any human supervision. These systems should be extensively trained and validated to guarantee safe human transportation. Any small errors in the system functionality may lead to fatal accidents and may endanger human lives. Deep learning methods are widely used for environment perception and prediction of hazardous situations. These techniques require huge amount of training data with both normal and abnormal samples to enable the vehicle to avoid a dangerous situation. The goal of this thesis is to generate simulations from real-world tricky collision scenarios for training and testing autonomous vehicles. Dashcam crash videos from the internet can now be utilized to extract valuable collision data and recreate the crash scenarios in a simulator. The problem of extracting 3D vehicle trajectories from videos recorded by an unknown monocular camera source is solved using a modular approach. The framework is divided into two stages: (a) extracting meaningful adversarial trajectories from short crash videos, and (b) developing methods to automatically process and simulate the vehicle trajectories on a vehicle simulator. / Dissertation/Thesis / Video Demonstration / Masters Thesis Computer Science 2019

Healthcare is an important part of life in most societies that attract a significant amount of public investment. Primary healthcare is a fundamental branch of the healthcare system where patients and doctors initially meet. Family Medicine Information Systems are developed in an effort to ease the daily work of family doctors with the help of information technology. Such systems are generally used for handling critical tasks such as managing health records of patients, monitoring pregnancy and keeping track of children&rsquo / s vaccination. Like any medical information technology, the usability of such systems is a vital concern for enabling efficient and effective primary healthcare operations. Family Medicine is a recently established practice in Turkey and there are a number of systems in service to aid the daily work of family doctors. However, none of these systems have been subjected to a systematic usability analysis. In this study, a usability analysis of a popular Family Medicine Information System used in Turkey is conducted. By combining several usability evaluation techniques, the study identified several important usability issues and provided recommendations for further improving the system. The main usability issue observed in the system was the overall complexity of the information presented at the main interface that often confused and misled the users. In order to address this problem, it is suggested that features related to the most frequent family medicine operations should be placed on the main screen, whereas remaining features should be organized under auxiliary pages with clear navigation aids.

Thesis (Ph. D.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 107-124). / Also available by subscription via World Wide Web / x, 124 leaves, bound 29 cm

Ce travail de thèse porte sur l'étude et le développement de stratégies innovantes pour la résolution, basée sur l'utilisation de la simulation et de la théorie de l'apprentissage statistique, de problèmes inverses dans le domaine contrôle non destructif (CND) par méthodes électromagnétiques. L’approche générale adoptée consiste à estimer un ensemble des paramètres inconnus, constituant un sous-ensemble des paramètres décrivant le scénario de contrôle étudié. Dans les cas de CND, les trois applications classiquement visées sont la détection, la localisation et la caractérisation de défauts localisés dans le matériau inspecté. Ce travail concerne d’une part la localisation et la caractérisation des fissures et d’autre part l'estimation de certains paramètres de sonde difficiles à maîtriser ou inconnus. Dans la littérature, de nombreuses méthodes permettant de remonter aux paramètres inconnus ont été étudiées. Les approches d'optimisation standard sont basées sur la minimisation d'une fonction de coût, décrivant l'écart entre les mesures et les données simulées avec un solveur numérique. Les algorithmes les plus répandus se fondent sur des approches itératives déterministes ou stochastiques. Cette thèse considère le problème de l'estimation de paramètres inconnus dans une perspective d'apprentissage statistique/automatique. L’approche supervisée adoptée est connue sous le nom de d’apprentissage par l'exemple (LBE en anglais). Elle se compose d’une première phase, dite hors ligne, pendant laquelle un « modèle inverse » est construit sur la base de la connaissance d’un ensemble de couples entrée/sortie connu, appelé ensemble d’entraînement. Une fois la phase d’apprentissage terminée et le modèle généré, le modèle est utilisé dans une phase dite en ligne pour prédire des sorties inconnues (les paramètres d'intérêt) en fonction de nouvelles entrées (signaux CND mesurés appartenant à un second ensemble dit de test) en temps quasi-réel. Lorsqu’on considère des situations pratiques d'inspection, en raison du grand nombre de variables impliquées, la création d'un modèle précis et robuste n’est pas une tâche triviale (problème connu comme la malédiction de la dimensionnalité). Grâce à une étude approfondie et systématique, l’approche développée dans cette thèse a conduit à la mise en place de différentes solutions capables d’atteindre une bonne précision dans l’estimation des paramètres inversés tout en conservant de très bonnes performances en temps de calcul. Le schéma LBE proposé dans cette thèse a été testé avec succès sur un ensemble des cas réels, en utilisant à la fois des données synthétiques bruitées et des mesures expérimentales. / The research activity of the PhD thesis focuses on the study and development of innovative strategies for the solution of inverse problems arising in the field of Non-Destructive Testing and Evaluation (NDT-NDE), based on the use of statistical learning theory. Generally speaking, the objective of the optimization stage is the retrieval of the unknown parameters within the studied electromagnetic scenario. In the case of NDT-NDE, the optimization problem, in terms of parameters to estimate, is divided into three stages, namely detection, localization and characterization. This work mainly addresses localization and characterization of crack(s) and/or estimation of probe(s) parameters. Unknown parameters, constituting a subset of the parameters set describing the electromagnetic scenario, are robustly estimated using several approaches. Standard optimization approaches are based on the minimization, by means of iterative approaches like stochastic and/or deterministic algorithms, of a cost function describing the discrepancy between measurements and prediction. This thesis considers the estimation problem in a machine learning perspective, adopting well known Learning-By-Example (LBE) paradigm. In a so-called offline phase, a surrogate inverse model is first fitted on a set of known input/output couples, generated through numerical simulations. Then, in a so-called online phase, the model predicts unknown outputs (the parameters of interest) based on new inputs (measured NDT signals) in quasi-real time. When considering practical inspection situations, due to the large number of variables involved (known as curse of dimensionality), obtaining an accurate and robust model is not a trivial task. This thesis carries out a deep and systematic study of different strategies and solutions to achieve simultaneously good accuracy and computational time efficiency in the parameters estimation. Moreover, a particular emphasis is put on the different approaches adopted for mitigating the curse of dimensionality issue. The proposed LBE schema has been tested with success on a wide set of practical problems, using both synthetic noisy data and experimental measurements.

<p dir="ltr">Learning-based systems (LBS) have become essential in various domains, necessitating the development of testing and evaluation (T&E) procedures specifically tailored to address the unique characteristics and challenges of LBS. However, existing frameworks designed for traditional systems do not adequately capture the intricacies of LBS, including their evolving nature, complexity, and susceptibility to adversarial actions. This study advocates for a paradigm shift in T&E, proposing its integration throughout the entire life cycle of LBS, starting from the early stages of development and extending to operations and sustainment. The research objectives focus on exploring innovative approaches for designing LBS-specific T&E strategies, creating an experimental testbed with multi-fidelity modeling capabilities, investigating the optimal degree of test and evaluation required for LBS, and examining the impact of system knowledge access and the delicate balance between T&E activities and data/model rights. These objectives aim to overcome the challenges associated with LBS and contribute to the development of effective testing approaches that assess their capabilities and limitations throughout the life cycle. The proposed experimental testbed will provide a versatile environment for comprehensive testing and evaluation, enabling researchers and practitioners to assess LBS performance across varying levels of complexity. The findings from this study will contribute the development of efficient testing strategies and practical approaches that strike a balance between thorough evaluation and data/model rights. Ultimately, the integration of continuous T&E insights throughout the life cycle of LBS aims to enhance the effectiveness and efficiency of capability delivery by enabling adjustments and improvements at each stage.</p>

The study reported in this thesis investigated Emirati students’ claims related to experiences of cultural bias of the reading component of the IELTS examination through a critical realist lens. Critical realism posits a layered reality which allows for the conceptualization of experiences as emerging from the interplay of events and mechanisms found in two other realms of reality – the actual and the real. Experiences, therefore, have a different ontological status than the events and the causal mechanisms to which they are attributed. Social realism was used to further explore the depth of the realm of the real through Archer’s construct of analytical dualism. This allowed for the placement of generative mechanisms into three domains: structure, culture, and agency. There were two parts to this investigation: a content analysis and a focus group study. The first part of the content analysis consisted of analyzing 60 reading passages from 20 IELTS examinations for a number of cultural categories. These included such things as cultural objects, social roles, idiomatic expressions, traditions and festivals, superstitions and beliefs, and political and historical settings. The second part of the content analysis focused on the question types and syntactical structure of the 5 different IELTS examinations that the focus groups students sat. All three components of the analysis – the cultural content, question types, and syntactical structure – were conducted at the level of the actual. Findings indicated that on average, an IELTS examination contained 14 cultural references of various kinds. Only 4% of all geographical references pertained to the Middle East with the biggest share being western locations. The most common question types were matching questions, fill in the blank questions, and yes/no questions with more than 50% of all questions requiring some form of higher order thinking due to text reinterpretation. The study also found that the question types were not consistently distributed over the examinations with each consisting of a different variety of questions and some even having repetitive question types on one reading examination. The second part of the study was the focus groups. Here, 21 Emirati students sat 5 different IELTS examinations. Upon test completion, these students underwent a semistructured interview to relate their experiences of the test. These experiences, at the level of the empirical, all shared 7 ideas: reading is hard, the questions are too difficult, the passages are too long and difficult, the topics are unfamiliar, the topics are not interesting, the vocabulary is too difficult, and there is not enough time. When the processes of retroduction and abduction were applied to both the content analysis and these common experiences, numerous structures and discourses at the level of the real were identified as having contributed to the emergence of the feeling of bias at the level of the empirical. These structures included such things as the students’ school system (eg. curriculum, assessment, instructors etc.), religion, literacy practices, and home. In the cultural domain, a number of discourses were found to contribute to the experiences at the level of the empirical. Amongst these were the ‘Unimportance of Reading’, the culture of ‘Obedience’, the rejection of the ‘un-Islamic’, and the students’ sense of ‘Entitlement’.