Ergonomic parameters of word processors in use

Through a questionnaire survey completed by 342 respondents and detailed interviews within 26 organizations a number of findings have emerged about the design and use of the word processors currently available. Though there is a high level of general satisfaction with what is currently available, there is no room for complacency. For example, one in five operators do not prefer their word processors to a typewriter and most organizations only use their word processors for a limited range of special applications. Dissatisfaction is strongest in respect of the design and use of the desk and chair, especially because of the lack of appropriate storage space and facilities. The noise created by the printer is also a frequent cause of complaint. At present the great majority of operators are new to their word processors. They are using them for limited purposes and do not have any experience of other machines. They typically therefore use their word processors as best they can in their particular circumstances without too much concern for improvement. Because of the power of the equipment currently available they are reasonably happy with their lot.     

Action graphs and user performance analysis

A user operating an interactive system performs actions such as “pressing a button” and these actions cause state transitions in the system. However to perform an action, a user has to do what amounts to a state transition themselves, from the state of having completed the previous action to the state of starting to perform the next action; this user transition is out of step with the system's transition. This paper introduces action graphs, an elegant way of making user transitions explicit in the arcs of a graph derived from the system specification. Essentially, a conventional transition system has arcs labeled in the form “user performs action A” whereas an action graph has arcs labelled in the form “having performed action P, the user performs Q.” Action graphs support many modelling techniques (such as GOMS, KLM or shortest paths) that could have been applied to the user's actions or to the system graph, but because it combines both, the modelling techniques can be used more powerfully.Action graphs can be used to directly apply user performance metrics and hence perform formal evaluations of interactive systems. The Fitts Law is one of the simplest and most robust of such user modelling techniques, and is used as an illustration of the value of action graphs in this paper. Action graphs can help analyze particular tasks, any sample of tasks, or all possible tasks a device supports—which would be impractical for empirical evaluations. This is an important result for analyzing safety critical interactive systems, where it is important to cover all possible tasks in testing even when doing so is not feasible using human participants because of the complexity of the system.An algorithm is presented for the construction of action graphs. Action graphs are then used to study devices (a consumer device, a digital multimeter, an infusion pump) and results suggest that: optimal time is correlated with keystroke count, and that keyboard layout has little impact on optimal times. Many other applications of action graphs are suggested.     

Graphical versus textual software measurement modelling: an empirical study

Model-driven Engineering (MDE) has attained great importance in both the Software Engineering industry and the research community, where it is now widely used to provide a suitable approach with which to improve productivity when developing software artefacts. In this scenario, measurement models (software artefacts) have become a fundamental point in improvement of productivity, where MDE and Software Measurement can reap mutual benefits. MDE principles and techniques can be used in software measurement to build more automatic and generic solutions, and to achieve this, it is fundamental to be able to develop software measurement models. To facilitate this task, a domain-specific language named “Software Measurement Modelling Language” (SMML) has been developed. This paper tackles the question of whether the use of SMML can assist in the definition of software measurement models. An empirical study was conducted, with the aim of verifying whether SMML makes it easier to construct measurement models which are more usable and maintainable as regards textual notation. The results show that models which do not use the language are more difficult—in terms of effort, correctness and efficiency—to understand and modify than those represented with SMML. Additional feedback was also obtained, to verify the suitability of the graphical representation of each symbol (element or relationship) of SMML.     

System-level performance evaluation of reconfigurable processors

Reconfigurable architectures that tightly integrate a standard CPU core with a field-programmable hardware structure have recently been receiving increased attention. The design of such a hybrid reconfigurable processor involves a multitude of design decisions regarding the field-programmable structure as well as its system integration with the CPU core. Determining the impact of these design decisions on the overall system performance is a challenging task. In this paper, we first present a framework for the cycle-accurate performance evaluation of hybrid reconfigurable processors on the system level. Then, we discuss a reconfigurable processor for data-streaming applications, which attaches a coarse-grained reconfigurable unit to the coprocessor interface of a standard embedded CPU core. By means of a case study we evaluate the system-level impact of certain design features for the reconfigurable unit, such as multiple contexts, register replication, and hardware context scheduling. The results illustrate that a system-level evaluation framework is of paramount importance for studying the architectural trade-offs and optimizing design parameters for reconfigurable processors.     

Toward the gestural interface: comparative analysis between touch user interfaces versus gesture-based user interfaces on mobile devices

Universal Access in the Information Society - Human–computer interaction is transformed as well as the technology used to achieve it. This paper discusses the ease of use of a classic touch...     

Speech technology for automatic teller machines: an investigation of user attitude and performance

Despite the success and widespread use of Automatic Teller Machines (ATMs), a significant proportion of bank customers can not or will not use them, or experience difficulties in their interactions. Speech technology has been suggested as a means by which non-users might be encouraged to use ATMs, while simultaneously improving usability for all. The potential advantages of speech interfaces include hands-free and eyes-free use for physically- and visuallyimpaired users, and improved ease and speed of use through increased ‘naturalness’ of the interaction. This study investigated user attitudes to the concepts of a speech-based ATM, via large-scale survey and a series of focus groups. Objective performance was also considered in user trials with a prototype speech-driven ATM. The idea of using speech for ATM transactions led to a number of concerns. Privacy (the concern over one's personal financial details being overheard) and security (the fear of potential attackers hearing the user withdraw cash) were the major reasons given. The user trials confirmed that possible solutions, such as the adoption of a hood over the ATM or the use of a telephone handset as the speech input/output device, were ineffective. Groups of impaired users, particularly visually-impaired subjects, were more positive about the concept of speech, citing various difficulties with current visual-manual interactions. Most non-users, however, would not be encouraged to use ATMs with the addition of speech. The paper discusses these and other issues relating to the likely success of using speech for ATM applications.     

Graphical user interface (GUI) testing: Systematic mapping and repository

ContextGUI testing is system testing of a software that has a graphical-user interface (GUI) front-end. Because system testing entails that the entire software system, including the user interface, be tested as a whole, during GUI testing, test cases—modeled as sequences of user input events—are developed and executed on the software by exercising the GUI’s widgets (e.g., text boxes and clickable buttons). More than 230 articles have appeared in the area of GUI testing since 1991.ObjectiveIn this paper, we study this existing body of knowledge using a systematic mapping (SM).MethodThe SM is conducted using the guidelines proposed by Petersen et al. We pose three sets of research questions. We define selection and exclusion criteria. From the initial pool of 230 articles, published in years 1991–2011, our final pool consisted of 136 articles. We systematically develop a classification scheme and map the selected articles to this scheme.ResultsWe present two types of results. First, we report the demographics and bibliometrics trends in this domain, including: top-cited articles, active researchers, top venues, and active countries in this research area. Moreover, we derive the trends, for instance, in terms of types of articles, sources of information to derive test cases, types of evaluations used in articles, etc. Our second major result is a publicly-accessible repository that contains all our mapping data. We plan to update this repository on a regular basis, making it a “live” resource for all researchers.ConclusionOur SM provides an overview of existing GUI testing approaches and helps spot areas in the field that require more attention from the research community. For example, much work is needed to connect academic model-based techniques with commercially available tools. To this end, studies are needed to compare the state-of-the-art in GUI testing in academic techniques and industrial tools.     

Procedural versus content‐related hints for word problem solving: an exploratory study

For primary school students, mathematical word problems are often more difficult to solve than straightforward number problems. Word problems require reading and analysis skills, and in order to explain their situational contexts, the proper mathematical knowledge and number operations have to be selected. To improve students' ability in solving word problems, the problem solving process could be supported by procedural and content specific guidance or with only procedural support.. This paper evaluates the effect of two types of hints, procedural only and content‐procedural, provided by a computer programme presented in two versions. Students of grade 6 were randomly assigned to these two versions, which offered five lesson units consisting of eight word problems each. The results indicate that on average the students in the procedural‐content hints group (n = 54) finished about just as many problems in the programme as their counterparts in the procedural‐only condition (n = 51). However, the participants in the first group solved more problems correctly and improved their problem‐solving skills more as indicated by the scores on the problem‐solving post‐test. Apart from presenting our analysis of the findings of this study, also its limitations and its possible implications for future research are discussed in this paper.     

Utilizing high technology: Computer-aided-design and user performance

A recently developed work-sample test was employed to assess individual performance utilizing computer-aided design technology. Overall task performance, as well as perceived difficulty, confidence, and latency, were found to be predicted by a hypothesized set of individual difference variables. Task performance, was found to be associated with perceptual skill and degree of experience. Confidence in judgments was predicted by perceptual skill, attitudes, and sex of the operator. Perceived difficulty was predicted by perceptual skill and attitudes. The final criterion variable, latency, was found to be predicted by attitudes and sex of the operator. Some of the most interesting findings relate to sex differences. Overall, the task performance of males and female subjects did not differ. However, while female subjects accomplished the task in less time, they were less confident in their judgments and found the task to be more difficult. Findings are discussed as they pertain to previous research and employee selection.     

IS service performance: self-perceptions and user perceptions

User evaluation of the quality of an information system (IS) and its service is often a major factor in the performance evaluation of the IS staff. While views of users are critical, user evaluation may be incomplete and prompt inappropriate decisions regarding the delivery of the IS service. Three hundred and sixty degree evaluation techniques strive to avoid unjustified actions by eliciting feedback from multiple stakeholders to calibrate expectations more effectively and set the most appropriate future goals. Evidence from a survey of 193 IS users and IS staff members clarified the helpfulness of the principles in 360° feedback with regard to IS staff performance.     

Secretarial attitudes towards word processors as a function of familiarity and locus of control

The purpose of the present study was to investigate dimensions of secretarial anxiety, eagerness, and curiosity with respect to word processing equipment. Such variables as familiarity, formal training, physical proximity to the equipment, degree of influence in the decision to acquire a word processor, and frequency of use were seen as potential predictors of such attitudes. Additionally, two trait-like dimensions were measured, locus of control and complexity. Questionnaires were sent to 408 secretaries employed at a mid-western university. The response rate was 59 per cent (n = 241). People who had not used word processing equipment were more anxious than those individuals who had. Moreover, frequency of use for people with experience was related to greater change in anxiety levels. While familiarity reduced anxiety, it also tended to reduce curiosity. Frequency of word processor use was related to several variables. For instance, frequency of use was related to how positively the person evaluated the processor as affecting their work capabilities. Heavy users felt that the manuals were less helpful. Internally controlled individuals were more eager, curious and less anxious, while cognitively complex individuals were more curious about word processors. The applied implications of the findings are discussed.     

A structural model of end user computing satisfaction and user performance

The proliferation of end user computing has necessitated the development of reliable and valid instruments that measure satisfaction in this environment and evaluate its success when used in improving user performance. An instrument for measurement of end user computing satisfaction (EUCS) is developed. Using exploratory factor analysis, six attitudinal dimensions for measurement of EUCS are first identified. Structural equation modelling techniques are then used to explore the relationship between EUCS and user performance. It is shown that the six attitudinal dimensions of EUCS account for a significant portion of the variation in user performance.     

Thermal analysis and modeling of embedded processors

This paper presents a complete modeling approach to analyze the thermal behavior of microprocessor-based systems. While most compact modeling approaches require a deep knowledge of the implementation details, our method defines a black box technique which can be applied to different target processors when this detailed information is unknown. The obtained results show high accuracy, applicability and can be easily automated. The proposed methodology has been used to study the impact of code transformations in the thermal behavior of the chip. Finally, the analysis of the thermal effect of the source code modifications can be included in a temperature-aware compiler which minimizes the total temperature of the chip, as well as the temperature gradients, according to these guidelines.     

基于UW帧结构水声通信系统及其性能分析

设计了一种基于UW(Unique Word)帧结构的单载波频域均衡(SC-FDE)水声通信系统框架,论述了系统的基本原理。为解决帧同步过程中出现由水声多径引起的相关峰峰值分裂现象,提出一种基于UW序列的相关同步算法,使系统的同步精度显著提高。同时给出了基于UW序列的多普勒频移的估计和校正、信道估计和频域均衡算法。最后对系统的性能进行了分析。结果表明:采用相关同步算法的基于UW帧结构的单载波频域均衡水声通信系统能够显著提高在较复杂的信道条件下的帧同步精度,对水声信道中严重的多普勒频移和多径信道进行有效的估计,并能够对时变信道进行跟踪,在高信噪比下系统有较低的误码率,对水声通信有良好的应用价值。     

Re-examining information systems user performance: Using data mining to identify properties of IS that lead to highest levels of user performance

As competitive pressures increase, managers try to realize every bit of productivity from people, business processes and new information technologies (IT). This leads one to ask, how can managers configure information systems to achieve higher levels of performance from end users? In this regard, managers continually seek advice on how to meet the promises and expectations of continued increases in productivity through the use of IT. However, results from research on how to achieve higher performance through the use of IT in organizations has been mixed. Consequently, it has been difficult for IS researchers to give managers any advice on investing in specific aspects of IS that would lead to the highest performance possible. We focus on this question in this research. We use a data mining approach to tease out information about specific characteristics of IS that managers can manipulate to achieve desired outcomes with regards to individual performance. Our findings offer both researchers and managers significant new knowledge that can make a difference to IT user performance research theory and the practice of user performance management. Further, our research method offers a novel approach to linking theory and practice in IS research, a problem that is of great concern to many IS researchers. The approach is generalized and can be implemented by academic or industry researchers who are interested in generating hypotheses from data for the purpose of theoretical or applied research.     

DSC: scheduling parallel tasks on an unbounded number of processors

We present a low-complexity heuristic, named the dominant sequence clustering algorithm (DSC), for scheduling parallel tasks on an unbounded number of completely connected processors. The performance of DSC is on average, comparable to, or even better than, other higher-complexity algorithms. We assume no task duplication and nonzero communication overhead between processors. Finding the optimum solution for arbitrary directed acyclic task graphs (DAG's) is NP-complete. DSC finds optimal schedules for special classes of DAG's, such as fork, join, coarse-grain trees, and some fine-grain trees. It guarantees a performance within a factor of 2 of the optimum for general coarse-grain DAG's. We compare DSC with three higher-complexity general scheduling algorithms: the ETF by J.J. Hwang, Y.C. Chow, F.D. Anger, and C.Y. Lee (1989); V. Sarkar's (1989) clustering algorithm; and the MD by M.Y. Wu and D. Gajski (1990). We also give a sample of important practical applications where DSC has been found useful     

A methodology for interactive evaluation of user reactions to software packages: an empirical analysis of system performance,interaction, and run time

This study deals with identifying primary factors which determine the usefulness of computer-assisted instruction (CAI). Usefulness is defined as user performance score. The study establishes linear models which explain the effects of CAI modifications designed to improve the utilization of computer facilities as well as users' performance.     

Civilian pepper spray for self defense: Understanding user perception and impact of design on user performance

Pepper spray is widely used in the US, and is marketed as an effective self-defense device. While pepper spray can be useful in deterring an attacker, many pepper spray owners do not have any experience using it. There is a dearth of published studies that focus on civilian pepper-spray use, not to mention first time pepper-spray users. A study to analyze pepper-spray designs with first-time users, to see how the design, specifically the safety mechanism, affects response time and overall performance would be helpful. The study was conducted in 2 parts – a survey to understand user perception, and a lab experiment using a 2 × 2 randomized block design with two designs of pepper sprays (side-slide safety and flip-top safety) and the two starting locations for the pepper spray (purse or pocket) as the manipulated factors. Results revealed a significant difference in response times between the flip-top pepper-spray and the side-slide pepper-spray. There was also a significant difference in response times between using the index or thumb as the trigger finger but no significant difference in response times when the pepper-spray for location (purse or pocket). Overall, participants rated the side-slide device as the most effective self-defense device.Relevance to industryBecause there is no other research in the area of first-time pepper-spray users, let alone civilian pepper-spray users, much can be learned about how well people use these devices in a real-world situation, and when there is a highly stressful situation how well does pepper-spray allow an individual to protect him or herself. This study starts the discussion on some of these topics.     

Testing the performance of spoken dialogue systems by means of an artificially simulated user

This paper proposes a new technique to test the performance of spoken dialogue systems by artificially simulating the behaviour of three types of user (very cooperative, cooperative and not very cooperative) interacting with a system by means of spoken dialogues. Experiments using the technique were carried out to test the performance of a previously developed dialogue system designed for the fast-food domain and working with two kinds of language model for automatic speech recognition: one based on 17 prompt-dependent language models, and the other based on one prompt-independent language model. The use of the simulated user enables the identification of problems relating to the speech recognition, spoken language understanding, and dialogue management components of the system. In particular, in these experiments problems were encountered with the recognition and understanding of postal codes and addresses and with the lengthy sequences of repetitive confirmation turns required to correct these errors. By employing a simulated user in a range of different experimental conditions sufficient data can be generated to support a systematic analysis of potential problems and to enable fine-grained tuning of the system.