Software applications for design and creation typically contain hundreds or thousands of commands, which collectively give users enormous expressive power. Unfortunately, rich feature sets also take a toll on usability. Current interfaces to feature-rich software address this dilemma by adopting menus, toolbars, and other hierarchical schemes to organize functionality—approaches that enable efficient navigation to specific commands and features, but do little to reveal how to perform unfamiliar tasks. We present an alternative task-centric user interface design that explicitly supports users in performing unfamiliar tasks. A task-centric interface is able to quickly adapt itself to the user’s intended goal, presenting relevant functionality and required procedures in task-specific customized interfaces. To achieve this, task-centric interfaces (1) represent tasks as first-class objects in the interface; (2) allow the user to declare their intended goal (or infer it from the user’s actions); (3) restructure the interface to provide step-by-step scaffolding for the current goal; and (4) provide additional knowledge and guidance within the application’s interface. Our inspiration for task-centric interfaces comes from a study we conducted, which revealed that a valid use case for feature-rich software is to perform short, targeted tasks that use a small fraction of the application’s full functionality. Task-centric interfaces provide explicit support for this use. We developed and tested our task-centric interface approach by creating AdaptableGIMP, a modified version of the GIMP image editor, and Workflows, an iteration on AdaptableGIMP’s design based on insights from a semi-structured interview study and a think-aloud study. Based on a two-session study of Workflows, we show that task-centric interfaces can successfully support a guided-and-constrained problem solving strategy for performing unfamiliar tasks, which enables faster task completion and reduced cognitive load as compared to current practices. We also provide evidence that task-centric interfaces can enable a higher-level form of application learning, in which the user associates tasks with relevant keywords, as opposed to low-level commands and procedures. This keyword learning has potential benefits for memorability, because the keywords themselves are descriptive of the task being learned, and scalability, because a few keywords can map to an arbitrarily complex set of commands and procedures. Finally, our findings suggest a range of different ways that the idea of task-centric interfaces could be further developed.

In this work, I present empirically validated techniques to realize gesture and touch interaction using a novel near touch tracking system. This study focuses on identifying the intended center of action for grab and release gestures close to an interactive surface. Results of this experiment inform a linear model that can approximate the intended location of grab and release actions with an accuracy of R^2 = 0.95 for horizontal position and R^2 = 0.84 for vertical position. I also present an approach for distinguishing which hand was used to perform the interaction. These empirical model data and near touch tracking system contributions provide new opportunities for natural and intuitive hand interactions with computing surfaces. / Graduate

A comprehensive study of accident records which have occured in Coal Mining Industries of Europe and U. S. A are analysed. The intention of the research was to establish relationships between the various accidents and prevention methods adopted by each country are evaluated and to assess the impact of industrial legislation in these various countries on accident rate are examined. The study analyses in paricular the fatal accident rate, and major and minor rate. The Major health hazards associated with coal mining are described in detail and discusses together with the Measurement of safety performance and its application in the Safety field. The study also examines the role of human factors in accidents also includes a summaries of fatal and major injury rates for 46 countries. Arising from the research a number of recommendations for improving safety are requires further research are indentified.

Generic airspace, or air traffic control sectors with similar operational characteristics, is an operational concept being proposed as a means of increasing staffing flexibility and reducing training times as part of the Federal Aviation Administration’s (FAA’s) Next Generation (NextGen) air traffic control (ATC) modernization efforts. A key need for implementing generic airspace is identifying groups of similar sectors with respect to training required for controllers to make transitions between those sectors. Through the development and validation process of the studies performed in this thesis, a structure-based classification scheme was found to be an effective way to classify sectors in order to support a minimal differences training approach to generic airspace. The resulting classes of sectors are expected to have fewer transition barriers and support increased staffing flexibility. In order to assess similarities of airspace sectors, factors affecting how easily a controller makes a transition from one sector to another were identified using semi-structured interviews with experienced air traffic controllers. The most important factors appear to reflect familiarity with types of operations and common traffic patterns, providing a basis for classifying groups of sectors. The controllers identified some techniques that are easily transferable as well. Some factors that are very specific to transitions were identified as well, such as “knowing the neighbor sectors” and “coastal area” factors. Based on the most important factors, traffic patterns in 404 high-altitude National Airspace System (NAS) sectors were examined for common traffic patterns. These traffic patterns were used as the basis for two classification approaches, a holistic classification approach and a decompositional classification approach. These approaches are used to classify current air traffic control sectors into classes with common structural characteristics. The results identify existing sectors with near-term potential as being generic sectors that support a minimal differences training approach to generic airspace. Further analysis with the sector classification results identified that the number of factors incorporated in the classification methods are directly associated with the method's effectiveness. In order to examine the validity of the developed classification methods and to assess the relative importance of the factors involving transitions identified by the interviews, an online survey was conducted with 56 air traffic controllers. The results indicated that the classification methods developed support controllers' perception of airspace similarities. Some qualitative data gained from the survey provides an insightful aspect for future steps continuing this study such as additional important factors to be considered. Some of these factors are considered as part of the classification schemes developed in this thesis while some are yet to be incorporated. Some of these additional factors were found to be more feasible to be incorporated into future classification schemes than other factors.

Recent decades have been witness to explosive leaps in manufacturing productivity. Advances in communication technology, computing speed, control theory, and sensing technology have been significant contributors toward the increased productivity and efficiency that industry has exhibited. The continued growth of technological equipment and engineering knowledge challenges engineers to fully utilize these advancements in more sophisticated and useful automation systems. One such application involves enhancing bridge and gantry crane operation. These systems are used throughout the globe, and are critical aspects of industrial productivity. Consequently, improving the operational effectiveness of cranes can be extremely valuable. Effective control of cranes can be largely attributed to two distinct, but related aspects crane manipulation: 1) the expertise of operators, which are responsible for issuing commands to the structures, and 2) the dynamic properties of cranes, which influence how the structures respond to issued commands. Accordingly, the operational efficiency of cranes can be influenced by changing both the way that operators issue commands to cranes, and also how the crane responds to issued commands. This thesis is concerned with dynamic control theory of flexible machines, and human/machine interaction, especially as these areas relate to industrial crane control. In the area of dynamic control, this thesis investigates control strategies that are specifically suited for use on systems that possess common actuator nonlinearities, like saturation, rate limiting, dead-zone, backlash, and finite-state actuation. In the area of human/machine interaction, this thesis investigates the effects of different crane interface devices on the operational efficiency of cranes.

A framework for understanding the social responses to virtual humans suggests that human-like characteristics (e.g., facial expressions, voice, expression of emotion) act as cues that lead a person to place the agent into the category "human" and thus, elicit social responses. Given this framework, this research was designed to answer two outstanding questions that had been raised in the research community (Moon&Nass, 2000): 1) If a virtual human has more human-like characteristics, will it elicit stronger social responses from people? 2) How do the human-like characteristics interact in terms of the strength of social responses? Two social psychological (social facilitation and politeness norm) experiments were conducted to answer these questions. The first experiment investigated whether virtual humans can evoke a social facilitation response and how strong that response is when participants are given different cognitive tasks (e.g., anagrams, mazes, modular arithmetic) that vary in difficulty. They did the tasks alone, in the company of another person, or in the company of a virtual human that varied in terms of features. The second experiment investigated whether people apply politeness norms to virtual humans. Participants were tutored and quizzed either by a virtual human tutor that varied in terms of features or a human tutor. Participants then evaluated the tutor's performance either directly by the tutor or indirectly via a paper and pencil questionnaire. Results indicate that virtual humans can produce social facilitation not only with facial appearance but also with voice recordings. In addition, performance in the presence of voice synced facial appearance seems to elicit stronger social facilitation (i.e., no statistical difference compared to performance in the human presence condition) than in the presence of voice only or face only. Similar findings were observed with the politeness norm experiment. Participants who evaluated their tutor directly reported the tutor's performance more favorably than participants who evaluated their tutor indirectly. In addition, this valence toward the voice synced facial appearance had no statistical difference compared to the valence toward the human tutor condition. The results suggest that designers of virtual humans should be mindful about the social nature of virtual humans.

In order to investigate the etiology of and evaluate interventions for work-related back injuries, researchers need efficient, accurate occupational exposure assessment methods suitable for large samples. The chapters in this thesis examine critical decisions using electromyography (EMG): How should exposure be measured? For what duration? Who should be measured, and how many times? Low-back EMG, or muscle activity data, was collected during 138 full-shift field measurements over 30 different job titles at 50 different worksites in 5 heavy industries: forestry, transportation, wood products, construction, and warehousing. Observations and self-reports of posture, manual materials handling (MMH), and driving exposures were collected concurrently. 1) Variability of EMG calibration measurements was investigated on right/left sides, multiple trials, 4 positions, and pre/post-shift. Position accounts for the majority of explained variability; there is little to gain by measuring multiple trials or pre- and post-shift, but measuring both sides and multiple positions is worthwhile. 2) Observation and self-report data were easier to collect and cheaper than the EMG direct measure. Costs and successful field performance need to be weighed against the added data detail when making choices about exposure assessment techniques for epidemiological studies. 3) Observed and self-reported exposures were used to predict EMG exposure metrics using mixed multiple linear regression models. Regression models using observed variables predicted 43-50% of the variability in the EMG metrics, while self-reported variables predicted 21%-36%. The observation exposure model provides a low-cost alternative to direct measurement. The self-reported exposure model should be considered with more caution. 4) Full-shift EMG data was resampled for 4, 2, and 1 hour, and for 10 and 2 minute durations to determine the optimal sampling duration. Bias was consistently low, but shorter durations had higher absolute error, percentage error, and limits of agreement. Durations of 4 and 2 hours may be acceptable but those less than 1 hour had large errors. 5) Components of EMG variance were calculated between- and within-subject, and between- industry, company, job, and post hoc grouping. Resolution, contrast, and exposure-response relationship attenuation were calculated for each grouping scheme. The post hoc scheme had the highest contrast and lowest resolution.

This thesis examines the role of intuition in the way that people operate unfamiliar devices, and the importance of this for designers. Intuition is a type of cognitive processing that is often　non-conscious and utilises stored experiential knowledge. Intuitive interaction involves the use of knowledge gained from other products and/or experiences. Therefore, products that people use intuitively are those with features they have encountered before. This position has been supported by two initial experimental studies, which revealed that prior exposure to products employing similar features helped participants to complete set tasks more quickly and intuitively, and that familiar　features were intuitively used more often than unfamiliar ones. Participants who had a higher level of familiarity with similar technologies were able to use significantly more of the　features intuitively the first time they　encountered them, and were significantly quicker at doing the tasks. Those who were less familiar with relevant technologies required more　assistance. A third experiment was designed to test four different interface designs on a remote control in order to establish which of two variables - a feature's appearance or its location - was more important in making a design intuitive to use. As with the previous experiments, the findings of Experiment 3 suggested that performance is　affected by a person's level of familiarity with similar technologies. Appearance (shape, size and labelling of buttons) seems to be the variable that most affects time spent on a task and intuitive uses. This suggests that the cues that people store in memory about a product's features depend on how the features look, rather than where on the product they are placed. Three principles of intuitive interaction have been developed. A conceptual tool has also been devised to guide designers in their planning for intuitive interaction. Designers can work with these in order to make interfaces intuitive to use, and thus help users to adapt more easily to new products and product types.

The implementation of In-Vehicle Intelligent Transport Systems (ITS) is becoming a common occurrence in modern vehicles. Automobile manufacturers are releasing vehicles with many forms of sophisticated technologies that remove much of the responsibility of controlling an automobile from the driver. These In-Vehicle Intelligent Transport Systems have stemmed from a genuine need in regards to road safety, however there are advantages and disadvantages associated with ITS. Each different form of technology has its own inherent compromises in relation to road safety, driver behaviour and driver comfort. This thesis outlines the benefits and detrimental effects associated with current In-Vehicle Intelligent Transport Systems and details the development and user interface testing of an adaptive brake light. The adaptive brakelight concept aims to provide drivers with the advantages of an In-Vehicle ITS whilst removing the disadvantages. The technology will help drivers judge the braking pattern of the car in front, thus allowing them to react appropriately and potentially reducing the occurrence of rear-end crashes. The adaptive brake light concept was tested in comparison to a standard brake light and BMW inspired brake light in a series of user interface tests. The adaptive brake light was shown overall to be an improved method of displaying the varying levels of deceleration of a lead vehicle. Whilst different age and gender groups responded differently to the adaptive brake light, it was shown to be of benefit to the majority and the most at risk groups responded positively to the adaptive brake light. This research shows that an adaptive brake light can provide a benefit in regards to road safety when compared to a standard brake light interface. It is hoped that further development of variable brake lights will result from this research and possibly lead to the implementation of the technology to automobiles and other forms of transport.

This report recommends a strategy for the introduction of aviation style Crew Resource Management (CRM) to the offshore drilling industry. The purpose of this study was to investigate ways CRM could be applied to the offshore drilling industry as a means of mitigating the risks of human error, and in particular risks to health and safety. Research has been conducted in accordance with accepted social science research methodologies. Key processes involved a formal literature review plus the formation of a Nominal Reference Group and application of the Delphi Technique as the primary data gathering method. Case studies have been used throughout this report to provide examples of key points and to illustrate the need for effective management of human error in both the aviation and drilling industries. Results from this study provided the basis for the development of a preferred implementation plan as a practical means for adopting the principles of CRM to the offshore drilling industry. Recommendations for furthering this work include the need to benchmark training as a means of providing better evidence that CRM leads to improved safety and operational performance, the need to develop a business plan to justify the cost and effort, the need to further involve key stakeholders in the process, and they need to solicit endorsement for this project from influential industry bodies.