768 research outputs found

    An examination of the weaknesses in current online help systems and a proposed solution using an integrated information base

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    This thesis reports results of a research study into the usefulness of On-line Help Systems for application software users. The main objective of the research was to examine existing On-line Help systems, identify their weaknesses, and propose a means of rectifying the problems identified. A study of the available relevant literature revealed that both users and designers have divergent views as to the overall usability and efficacy of On-line Information, and this diversity has contributed to the problems inherent in On-line Help systems. An initial user survey was conducted with a group of computer users who were professionals in their own areas, many of whom also have considerable experience in the applications examined. The results are in agreement with the hypothesis that in spite of the long history of software development and the existence of research in the area, users of On-line Help Systems still find them unsatisfactory. The results also revealed that even experienced users find some aspects of existing Online Help Systems difficult to use, and that, in general current versions are not well received. A set of exploratory experiments has been carried out with users interacting with Microsoft Excel, using the On-line Help system at one sitting and the User Manual at another. These investigations revealed the existence of design and accessibility problems. Three terms best describe the problems identified - Vocabulary, Compartmentalisation, and the lack of an Integrated Base. An optimal approach to the design of On-line Help systems that will overcome these problems is proposed and a prototype system implemented and evaluated. The research has achieved its aim of providing a contribution to the design and implementation of On-line Help Systems that should enhance both the usability and efficacy of On-line support systems

    The evaluation of a novel haptic machining VR-based process planning system using an original process planning usability method

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    This thesis provides an original piece of work and contribution to knowledge by creating a new process planning system; Haptic Aided Process Planning (HAPP). This system is based on the combination of haptics and virtual reality (VR). HAPP creates a simulative machining environment where Process plans are automatically generated from the real time logging of a user’s interaction. Further, through the application of a novel usability test methodology, a deeper study of how this approach compares to conventional process planning was undertaken. An abductive research approach was selected and an iterative and incremental development methodology chosen. Three development cycles were undertaken with evaluation studies carried out at the end of each. Each study, the pre-pilot, pilot and industrial, identified progressive refinements to both the usability of HAPP and the usability evaluation method itself. HAPP provided process planners with an environment similar to which they are already familiar. Visual images were used to represent tools and material whilst a haptic interface enabled their movement and positioning by an operator in a manner comparable to their native setting. In this way an intuitive interface was developed that allowed users to plan the machining of parts consisting of features that can be machined on a pillar drill, 21/2D axis milling machine or centre lathe. The planning activities included single or multiple set ups, fixturing and sequencing of cutting operations. The logged information was parsed and output to a process plan including route sheets, operation sheets, tool lists and costing information, in a human readable format. The system evaluation revealed that HAPP, from an expert planners perspective is perceived to be 70% more satisfying to use, 66% more efficient in completing process plans, primarily due to the reduced cognitive load, is more effective producing a higher quality output of information and is 20% more learnable than a traditional process planning approach

    A study of novice programmer performance and programming pedagogy.

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    Identifying and mitigating the difficulties experienced by novice programmers is an active area of research that has embraced a number of research areas. The aim of this research was to perform a holistic study into the causes of poor performance in novice programmers and to develop teaching approaches to mitigate them. A grounded action methodology was adopted to enable the primary concepts of programming cognitive psychology and their relationships to be established, in a systematic and formal manner. To further investigate novice programmer behaviour, two sub-studies were conducted into programming performance and ability. The first sub-study was a novel application of the FP-Tree algorithm to determine if novice programmers demonstrated predictable patterns of behaviour. This was the first study to data mine programming behavioural characteristics rather than the learner’s background information such as age and gender. Using the algorithm, patterns of behaviour were generated and associated with the students’ ability. No patterns of behaviour were identified and it was not possible to predict student results using this method. This suggests that novice programmers demonstrate no set patterns of programming behaviour that can be used determine their ability, although problem solving was found to be an important characteristic. Therefore, there was no evidence that performance could be improved by adopting pedagogies to promote simple changes in programming behaviour beyond the provision of specific problem solving instruction. A second sub-study was conducted using Raven’s Matrices which determined that cognitive psychology, specifically working memory, played an important role in novice programmer ability. The implication was that programming pedagogies must take into consideration the cognitive psychology of programming and the cognitive load imposed on learners. Abstracted Construct Instruction was developed based on these findings and forms a new pedagogy for teaching programming that promotes the recall of abstract patterns while reducing the cognitive demands associated with developing code. Cognitive load is determined by the student’s ability to ignore irrelevant surface features of the written problem and to cross-reference between the problem domain and their mental program model. The former is dealt with by producing tersely written exercises to eliminate distractors, while for the latter the teaching of problem solving should be delayed until the student’s program model is formed. While this does delay the development of problem solving skills, the problem solving abilities of students taught using this pedagogy were found to be comparable with students taught using a more traditional approach. Furthermore, monitoring students’ understanding of these patterns enabled micromanagement of the learning process, and hence explanations were provided for novice behaviour such as difficulties using arrays, inert knowledge and “code thrashing”. For teaching more complex problem solving, scaffolding of practice was investigated through a program framework that could be developed in stages by the students. However, personalising the level of scaffolding required was complicated and found to be difficult to achieve in practice. In both cases, these new teaching approaches evolved as part of a grounded theory study and a clear progression of teaching practice was demonstrated with appropriate evaluation at each stage in accordance with action researc

    Usability issues and design principles for visual programming languages

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    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Despite two decades of empirical studies focusing on programmers and the problems with programming, usability of textual programming languages is still hard to achieve. Its younger relation, visual programming languages (VPLs) also share the same problem of poor usability. This research explores and investigates the usability issues relating to VPLs in order to suggest a set of design principles that emphasise usability. The approach adopted focuses on issues arising from the interaction and communication between the human (programmers), the computer (user interface), and the program. Being exploratory in nature, this PhD reviews the literature as a starting point for stimulating and developing research questions and hypotheses that experimental studies were conducted to investigate. However, the literature alone cannot provide a fully comprehensive list of possible usability problems in VPLs so that design principles can be confidently recommended. A commercial VPL was, therefore, holistically evaluated and a comprehensive list of usability problems was obtained from the research. Six empirical studies employing both quantitative and qualitative methodology were undertaken as dictated by the nature of the research. Five of these were controlled experiments and one was qualitative-naturalistic. The experiments studied the effect of a programming paradigm and of representation of program flow on novices' performances. The results indicated superiority of control-flow programs in relation to data-flow programs; a control-flow preference among novices; and in addition that directional representation does not affect performance while traversal direction does - due to cognitive demands imposed upon programmers. Results of the qualitative study included a list of 145 usability problems and these were further categorised into ten problem areas. These findings were integrated with other analytical work based upon the review of the literature in a structured fashion to form a checklist and a set of design principles for VPLs that are empirically grounded and evaluated against existing research in the literature. Furthermore, an extended framework for Cognitive Dimensions of Notations is also discussed and proposed as an evaluation method for diagrammatic VPLs on the basis of the qualitative study. The above consists of the major findings and deliverables of this research. Nevertheless, there are several other findings identified on the basis of the substantial amount of data obtained in the series of experiments carried out, which have made a novel contribution to knowledge in the fields of Human-Computer Interaction, Psychology of Programming, and Visual Programming Languages

    An investigation into tacit knowledge management at the supervisory level.

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    An investigation into tacit knowledge management at the supervisory level Objective: The purpose of this study was to investigate how supervisors managed tacit knowledge. Aims: The aims were to understand what tacit knowledge looked like on the shop floor, to understand "experience‟ in terms of tacit knowledge, and to describe the methods and techniques that supervisors used to manage this elusive resource as they went about the task of achieving organisational goals. Method: Qualitative data was collected using a novel iterative participant observation method, where the researcher-as-instrument was embedded as a novice (but privileged) employee for extended periods in four different case study sites. Over the course of the study, the researcher took on the role of laboratory technician, electrical engineer, manufacturing process worker, and aircraft maintenance engineer. A grounded theory approach was taken to the analysis of the various field notes, photographs, video, audio, and found objects. The methodology was augmented with specialist qualitative research software to manage the data. Results: It was found that supervisors' tacit knowledge management activities can be classified according to formal and informal behaviours that correspond with Nonaka and Takeuchi's SECI knowledge life cycle. It was also found that a worker's task related tacit knowledge has seven aspects in five levels of competency, and their experience can be described in terms of 10 categories of tacit knowledge working capital. Insights attributed to the novel method of data collection produced an unexpected finding – the Home Guard model, which describes how the value of an individual's knowledge sharing activities is related to their power distance and self-confidence. Conclusions: The findings provide empirical support for existing knowledge management theory, identify specific supervisory behaviours that support tacit knowledge management on the shop floor, and extend the knowledge management discourse with new theories about knowledge sharing behaviours that have direct application to the supervisory role

    Contextualising simulation: the use of patient-focused hybrid simulation for clinical skills education

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    This thesis documents a research programme into the use of Patient-Focused Hybrid Simulation (PFHS) for clinical skills education. PFHS is an approach to simulating clinical skills that combines a simulated patient (SP) with a part-task trainer (PTT) embedding the simulation of procedural skills within a more holistic clinical context, potentially overcoming some of the shortcomings of single modality simulation. Although promising, there remains limited evidence supporting its use. Two studies were conducted using a mixed-method approach. The first study was based on the simulation of the management of a traumatic skin laceration and consisted of two parts: 1) investigating the use of PFHS as a means of introducing clinical challenge by modifying the clinical context in which a procedure is performed; 2) exploring clinician’s perception of the use of PFHS and PTT for assessing of clinical competence. These findings suggest that by changing the clinical context in which a procedure is performed, PFHS can potentially be used to objectively simulate challenge. It also demonstrated that PFHS when compared to PTT simulations was better able to induce authentic clinical behaviour within the simulation. Central to this is the presence of a human being (SP). The second study compared the use of PFHS to patients for the training and assessment of cardiovascular examination skills. Within the limitations of this study, no significant difference was observed between PFHS and real patient-trained students in terms of their post-training performance of cardiovascular examination on real patients. There also appeared to be degree of concurrent validity between assessment of competency with PFHS and with real patients when conducted as an Objective Structured Clinical Examination (OSCE). The work presented provides additional evidence to the existing literature to support the use of PFHS in clinical skills education. However, it also raises a multitude of questions particularly of how PFHS as well as simulation in general should be used and future directions for simulation research.Open Acces

    Motor learning induced neuroplasticity in minimally invasive surgery

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    Technical skills in surgery have become more complex and challenging to acquire since the introduction of technological aids, particularly in the arena of Minimally Invasive Surgery. Additional challenges posed by reforms to surgical careers and increased public scrutiny, have propelled identification of methods to assess and acquire MIS technical skills. Although validated objective assessments have been developed to assess motor skills requisite for MIS, they poorly understand the development of expertise. Motor skills learning, is indirectly observable, an internal process leading to relative permanent changes in the central nervous system. Advances in functional neuroimaging permit direct interrogation of evolving patterns of brain function associated with motor learning due to the property of neuroplasticity and has been used on surgeons to identify the neural correlates for technical skills acquisition and the impact of new technology. However significant gaps exist in understanding neuroplasticity underlying learning complex bimanual MIS skills. In this thesis the available evidence on applying functional neuroimaging towards assessment and enhancing operative performance in the field of surgery has been synthesized. The purpose of this thesis was to evaluate frontal lobe neuroplasticity associated with learning a complex bimanual MIS skill using functional near-infrared spectroscopy an indirect neuroimaging technique. Laparoscopic suturing and knot-tying a technically challenging bimanual skill is selected to demonstrate learning related reorganisation of cortical behaviour within the frontal lobe by shifts in activation from the prefrontal cortex (PFC) subserving attention to primary and secondary motor centres (premotor cortex, supplementary motor area and primary motor cortex) in which motor sequences are encoded and executed. In the cross-sectional study, participants of varying expertise demonstrate frontal lobe neuroplasticity commensurate with motor learning. The longitudinal study involves tracking evolution in cortical behaviour of novices in response to receipt of eight hours distributed training over a fortnight. Despite novices achieving expert like performance and stabilisation on the technical task, this study demonstrates that novices displayed persistent PFC activity. This study establishes for complex bimanual tasks, that improvements in technical performance do not accompany a reduced reliance in attention to support performance. Finally, least-squares support vector machine is used to classify expertise based on frontal lobe functional connectivity. Findings of this thesis demonstrate the value of interrogating cortical behaviour towards assessing MIS skills development and credentialing.Open Acces

    Human Factors of Integrating Speech and Manual Input Devices: The Case of Computer Aided Design

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    The thesis investigates integrating the use of speech input and manual input devices in human-computer systems. The domain of computer aided design (CAD) is used as a case study. A methodology for empirical evaluation of CAD systems is presented. The methodology is based on a framework that describes the input/output processes presumed to underlie performance in design activities, using behaviour protocols and performance indices as data. For modelling system behaviour, a framework derived from the Blackboard architecture of design is described. The framework employs knowledge sources to represent different behaviour types recruited during CAD performance. Variability in user behaviour throughout the investigation is explained with reference to the model. The problems that expert CAD users experience in using manual input devices are first documented in an observational study conducted at their workplace. This demonstrates that the unitary use of manual input resulted in non-optimal behaviour. Possible solutions to these problems, using speech input for some command and data entry tasks, are explored in three experiments. In each experiment, a comparative analysis of alternative systems is made using data obtained from naive and novice users. In Experiment 1, the use of speech as a unitary solution to the problems of manual input was also found to result in non-optimal behaviour and performance. The solution explored in Experiment 2 was to allocate some commands and alphanumeric data to each input device, using the frequency of use principle. This approach, however, entailed the additional problem of remembering which device to use. Experiment 3 evaluated the separate allocation of commands to speech input and numeric plus graphical data to manual input. Additionally, performance aids and feedback facilities were provided to users. This clear-cut assignment of device to task characteristics and the use of such aids led to an enhancement in speech performance, in addition to improving behaviour. The findings from this research are used to develop guidelines for an integrated CAD system involving speech and manual input. The guidelines, which are intended for use by end users, CAD implementors and system designers, were validated in the workplace by the latter. Lastly, the thesis contextualises the research within an ergonomics framework, mapping the research development from problem specification to application and synthesis. Problems with the investigation are also discussed, and suggestions made as to how these might be resolved
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