Designing a persuasive physical activity application for older workers: understanding end-user perceptions

Among the factors known to encourage healthy ageing is routine physical activity, a behaviour that is not common among the older age group. A Persuasive System Design (PSD) model offers guidelines for designing and evaluating systems aimed at reinforcing, changing or shaping underlying human behaviour and attitudes. The objective of this study was to investigate the perceptions of older workers towards persuasive principles of PSD that was integrated into an application specifically designed to encourage physical activity. Ten older workers aged 50–64 years with different physical activity levels participated in this study. Using a think-aloud technique, the participants interacted with a physical activity application, while verbally expressing their perceptions towards the persuasive elements. The results indicated that the older worker participants had positive views towards persuasive design principles that fell under the categories of primary task, dialogue support and credibility support. However, the persuasive principle of the social support category received contradictory views. Further, it was discovered that the personalisation of persuasive principles, the credibility of tailored contents and the establishment of a sense of similarity are imperative in the designing of effective persuasive physical activity applications targeting older workers.     

Cognitive processes in engineering design: a longitudinal study

Abstract

In this paper we report an empirical study of the cognitive processes of semi-expert electronics engineers pursuing real-world design projects. Extensive diary and interview data were analysed so as to reveal the organization of on-going design activity and the goals that were motivating behaviour. Our analyses indicated that subjects were implementing a highly systematic design strategy which deviated only a small amount (12%) from a top-down, depth-first procedure. Some of this deviation could be accounted for by social demands impinging on the individual designer, and whilst there was also evidence of ‘opportunistic’ deviation from a structured design approach, this did not appear to be a significant feature of our subjects' behaviour. We present a model of the design process as a set of production rules which describe an abstract ‘design schema’ for electronic engineering. This design schema embodies processes which control and co-ordinate problem-understanding and problem-structuring activity as well as the essentially top-down, depth-first pursuit of design solutions. The schema also allows for flexibility in the design process, permitting subjects to cope with contingencies arising through social influences and performance breakdowns. A further aspect of the design schema is that it encapsulates a ‘satisficing’ procedure which reflects a principle that dominated our engineers' solution-search and evaluation activity—they characteristically focused exclusively on initial, satisfactory (but usually sub-optimal) solution concepts rather than comparing alternatives with the aim of optimizing choices. We conclude our discussion by recommending facilities that we feel computer-based design aids should offer users if they are to be genuinely useful adjuncts to design activity.     

Interactive tool for analysis of time-delay systems with dead-time compensators

The problem of controlling delayed systems has been widely studied in the control community. The Smith predictor (SP) scheme was the most famous and efficient technique to cope with this problem. Afterwards, robustness problems and those related to the control of integrating and unstable delayed processes were resolved. This work presents an interactive tool for studying and understanding the different alternatives available for controlling systems with large delays. Interactive tools have provided excellent support for the control community during recent years. In this sense, the tool developed here helps to compare easily the performance of PID controllers and SP approaches for processes with delay, as well as other control structures used to solve different problems that the original SP has when integrator and unstable models are employed. Robustness problems due to presence of model uncertainties can also be analyzed. Furthermore, some real industrial processes are also described as motivation in the study of the problems presented in the paper. The tool incorporates a set of typical transfer functions based on these real industrial processes.     

Evaluation of integrated software development environments: Challenges and results from three empirical studies

Evidence shows that integrated development environments (IDEs) are too often functionality-oriented and difficult to use, learn, and master. This article describes challenges in the design of usable IDEs and in the evaluation of the usability of such tools. It also presents the results of three different empirical studies of IDE usability. Different methods are sequentially applied across the empirical studies in order to identify increasingly specific kinds of usability problems that developers face in their use of IDEs. The results of these studies suggest several problems in IDE user interfaces with the representation of functionalities and artifacts, such as reusable program components. We conclude by making recommendations for the design of IDE user interfaces with better affordances, which may ameliorate some of most serious usability problems and help to create more human-centric software development environments.     

Designing educational software with students through collaborative design games: The We!Design&Play framework

In this paper, we present a framework for the development of collaborative design games that can be employed in participatory design sessions with students for the design of educational applications. The framework is inspired by idea generation theory and the design games literature, and guides the development of board games which, through the use of adequate stimuli, rules and props, facilitate students in extracting and expressing their needs, desires and prospects regarding future educational software. To evaluate the proposed framework three studies were conducted. The first study aimed at the design of a web learning platform with the participation of 62 undergraduate higher education students in 13 design sessions; in the second study, a structured design approach was employed (12 sessions, 54 students) with the same design objective for comparison reasons; in the third study, the framework was deployed for the design of an electronic assessment application so as to examine its applicability in different learning domains (8 design sessions, 28 students). Students were very positive regarding both their participation and experience with the design games, and the needs elicited. The games favored a quick, broad exploration of the design space and facilitated the elicitation of numerous diverse needs and ideas, almost twice as many as produced by the structured approach. They also facilitated the creation of an informal atmosphere and limited the effects of common social influences on idea generation, such as social loafing, evaluation apprehension and production blocking. The three studies indicated that the proposed framework may simplify the development and employment of effective and efficient participatory design sessions in educational settings.     

A parameter-tuned genetic algorithm for statistically constrained economic design of multivariate CUSUM control charts: a Taguchi loss approach

In this research, the main parameters of the multivariate cumulative sum (CUSUM) control chart (the reference value k, the control limit H, the sample size n and the sampling interval h) are determined by minimising the Lorenzen–Vance cost function [Lorenzen, T.J., and Vance, L.C. (1986), ‘The Economic Design of Control Charts: A Unified Approach’, Technometrics, 28, 3–10], in which the external costs of employing the chart are added. In addition, the model is statistically constrained to achieve desired in-control and out-of-control average run lengths. The Taguchi loss approach is used to model the problem and a genetic algorithm, for which its main parameters are tuned using the response surface methodology (RSM), is proposed to solve it. At the end, sensitivity analyses on the main parameters of the cost function are presented and their practical conclusions are drawn. The results show that RSM significantly improves the performance of the proposed algorithm and the external costs of applying the chart, which are due to real-world constraints, do not increase the average total loss very much.     

Systems scenarios: a tool for facilitating the socio-technical design of work systems

Abstract

The socio-technical systems approach to design is well documented. Recognising the benefits of this approach, organisations are increasingly trying to work with systems, rather than their component parts. However, few tools attempt to analyse the complexity inherent in such systems, in ways that generate useful, practical outputs. In this paper, we outline the ‘System Scenarios Tool’ (SST), which is a novel, applied methodology that can be used by designers, end-users, consultants or researchers to help design or re-design work systems. The paper introduces the SST using examples of its application, and describes the potential benefits of its use, before reflecting on its limitations. Finally, we discuss potential opportunities for the tool, and describe sets of circumstances in which it might be used.

Practitioner Summary: The paper presents a novel, applied methodological tool, named the ‘Systems Scenarios Tool’. We believe this tool can be used as a point of reference by designers, end-users, consultants or researchers, to help design or re-design work systems. Included in the paper are two worked examples, demonstrating the tool’s application.     

The influence of a knowledge-based system on designers' cognitive activities: a study involving professional web designers

Over the last few decades, several usability knowledge-based systems have been developed to provide user interface designers with usability knowledge (e.g. heuristics, usability guidelines, standards). Such systems are intended to assist designers during the design process, and to improve the usability of the user interface being designed. However, the assumption that such systems actually improve the usability of the resulting user interface remains to be demonstrated: virtually no systems have been empirically tested by designers who create products. In order to confirm this assumption, we conducted an experimental study in which professional web designers had to create webpages, either using a knowledge-based system – MetroWeb – or without it. This study was intended to determine the influence of MetroWeb on the professional web designers' cognitive activity, and to find out whether MetroWeb actually assists them to develop a user-centred design. The results show that the web designers did not very often use MetroWeb while designing webpages; however, rather surprisingly, the designers who did use MetroWeb more often exhibited a user-centred activity than those working without MetroWeb. We conclude this paper by discussing these findings, and suggesting future possible ways of research intended to assist designers to adopt a user-centred approach to their activity.     

Motivation in software engineering industrial practice: A cross-case analysis of two software organisations

ContextThe research about motivation in software engineering has provided important insights into characterizing factors and outcomes related to motivation. However, the complex relationships among these factors, including the moderating and mediating effects of organisational and individual characteristics, still require deeper explanatory investigation.ObjectiveOur general goal is to build explanatory theories of motivation in different software organisations and to integrate these local theories towards a comprehensive understanding of the role of motivation in the effectiveness of the individuals and the teams in which they work. In this article, we describe the integrative synthesis of the results of two case studies performed with software organisations in different business contexts.MethodWe performed two case studies using a multiple-case, replication design, focusing on the software engineers as the unit of analysis. For 13 months, we conducted semi structured interviews, diary studies, and document analyses, and analysed the collected data using grounded theory procedures. The results of the two cases were synthesized using a meta-ethnography supported process.ResultsWe built translations of the concepts and propositions from the two studies into one another. We then used the translations to build a central story of motivation that synthesizes the individual stories. This synthesis is contextualized by the differences in organisational and individual characteristics.ConclusionThe differences in organisational contexts and in the characteristics of the software engineers in each study provided rich explanations for contrasts in perceptions and feelings about motivation in both organisations. The theory that emerged from the synthesis, supported by these explanations, provides a deeper understanding of the interplay between motivators and outcomes, and the needs and personal goals of the software engineers. This theory also characterises the role of team cohesion in motivation, advancing previous models about motivation in software engineering.     

Optimisation of a laparoscopic tool handle dimension based on ergonomic analysis

The techniques of Minimally Invasive Surgery (MIS) have quickly entered everyday surgical practice, and are steadily displacing traditional procedures. The reason is the advantages they have for the patient, both during surgery and in postoperative recovery. However, poor ergonomic design of the instruments used in MIS causes surgeons muscle fatigue and injuries (such as paraesthesia, etc.), forcing them to refrain from performing operations for several days or even weeks, which supposes costly losses of time and money.The objective of the present study was to optimize the handle size of a laparoscopic grasper tool. The study was conducted with the participation of 135 surgeons. Each participant performed a series of trials in which they executed the same action several times with the same tool (same in terms of the geometrical form of the handle) but of different dimensions (size) in order to determine the optimal diameter. The results were then subjected to a statistical analysis to study the relationship between the size of the surgeon's hand and the perceived optimal diameter of the handle from an ergonomic point of view.There stands out among the conclusions drawn from the study that there is indeed a relationship between the size of a surgeon's hand and the optimal handle size for them to use in surgery. In this sense, one of the most relevant results is that it is necessary to consider four different handle sizes groups (XS, S, M and L) instead of the three groups proposed by Greiner (1991). Another interesting result is that all surgeons in the smallest handle size group (XS) were women, and in the L group were men. Also it was interesting to note that, for the intermediate hand sizes (S and M), the sex of the surgeon conditioned the optimal handle size, and that the surgeon's experience and surgeon's handedness were not factors affecting the optimal diameter of the handle.Relevance to industryThe results of this work can assist designers of grasping tools in developing better handles and provide required sizing for improved comfort, performance and lowering the risk of cumulative traumatic disorders. It is important to note that it is not necessary to design the handle of the grasper tool for each surgeon hand, but also with four hand size categories is possible to offer an appropriate handle size for all surgeons independently of their hand sizes.     

Simple mappings,expressive movement: a qualitative investigation into the end-user mapping design of experienced mid-air musicians

In a New Interface for Musical Expression (NIME), the design of the relationship between a musician’s actions and the instrument’s sound response is critical in creating instruments that facilitate expressive music performance. A growing body of NIMEs expose this design task to the end performer themselves, leading to the possibility of new insights into NIME mapping design: what can be learned from the mapping design strategies of practicing musicians? This research contributes a qualitative study of four highly experienced users of an end-user mapping instrument to examine their mapping practice. The study reveals that the musicians focus on designing simple, robust mappings that minimize errors, embellishing these control gestures with theatrical ancillary gestures that express metaphors. However, musical expression is hindered by the unintentional triggering of musical events. From these findings, a series of heuristics are presented that can be applied in the future development of NIMEs.     

The design and development of a computerized tool support for conducting senior projects in software engineering education

This paper presents a computerized tool support, the Meetings-Flow Project Collaboration System (MFS), for designing, directing and sustaining the collaborative teamwork required in senior projects in software engineering (SE) education. Among many schools’ SE curricula, senior projects serve as a capstone course that provides comprehensive training in collaborative project development. With the focus on collaboration training, instructors of senior projects often address issues that include how to encourage collaboration and ensure that collaborative efforts are sustained throughout the project’s development. In order to help resolve these issues, the MFS takes a holistic approach. The meetings-flow concept that undergirds the MFS introduces a novel macro-level and meeting-oriented group process to guide the proceeding of the project’s collaborative work. The design of the MFS facilitates a computerized environment that helps to institutionalize and monitor such a group process. In introducing the MFS, we focus initially on the elaboration of the concept and design, after which we present and validate the system implementation and usage. We also evaluate the MFS and receive a positive result with respect to the educational issues raised in this paper. Finally, we comparatively summarize the MFS to discuss its values and the role it plays in CSCL (computer supported collaborative learning) and PBL (project-based learning) of SE education.     

Relational database as a tool in industrial design. Experience from a human factors engineering analysis of a module for manned space-flight

A human factors engineering analysis was carried out to verify that the CUPOLA—a module developed by the European Space Agency for the International Space Station—complies with an extensive set of human factors requirements. Analysis was carried out in three steps: task analysis, computer simulation of tasks and empirical test of tasks in a physical mock up. In advance to each step the method of assessment and type of information to be obtained were determined in detail and the way of documentation was established as input forms to a relational database. Advantages and drawbacks of this early formalisation as seen by project members are discussed in the present paper.

Relevance to industry

The method of early formalisation by a relational database used throughout the project showed to be a suitable tool in this human factors analysis of a working place under design. Early formalisation of the results and documentation served as a quality system supporting a homogeneous high standard of data collection and documentation. In industry, the use of relational databases underlying Product Data Management systems increases. This makes it relevant to try and link human factors work to these methods of documentation in order to promote the integration of human factors work at an early stage of product and production development.     

The foundations of a theory-aware authoring tool for CSCL design

One of the most useful ways to enhance collaboration is to create scenarios where learners are able to interact more effectively. Nevertheless, the design of pedagogically sound and well-thought-out collaborative learning scenarios is a complex issue. This is due to the context of group learning where the synergy among learners’ interactions affects learning processes and, hence, the learning outcome. Although many advances have been made to support the designing of collaborative learning scenarios through technology, a more systematic approach is lacking. With the limitations of the current designing methods and tools, it is difficult to develop intelligent authoring systems that can guide users in order to produce more effective collaboration. One of the main difficulties with creating a more consistent (computer-understandable) approach to designing collaboration is the necessity of proposing better ways to formalize the group learning processes. In this paper, we present an innovative approach that uses ontologies and concepts from learning theories to create a framework that represents collaborative learning and its processes. Ontologies provide the necessary formalization to represent collaboration, while learning theories provide the concepts to justify and support the development of effective learning scenarios. Such an approach contributes to establish the foundations for the development of the next generation of intelligent authoring systems referred to as theory-aware systems. To verify the viability and usefulness of our proposed ontological framework in the context of systematic design, the development and use of an intelligent authoring tool for CSCL design is presented. This system is able to reason on ontologies to give suggestions that help users to create theory-compliant collaborative learning scenarios. We carried out several experiments with teachers in a geometry drawing course and the results indicate that the system helps teachers to create and interchange their scenarios more easily and facilitates the selection of important pedagogical strategies that influence positively the designing and effectiveness of group activities.     

Contextualising design: Aspects of using usability context analysis and hierarchical task analysis for software design

Usability Context Analysis is part of ISO 9241-11 and, as such, is recommended for use in user-centred design. However, studies involving a critical assessment of usability context analysis within the software domain are scarce; this paper details two small studies that involved the use of usability context analysis (UCA) and hierarchical task analysis (HTA). The first system involved designing a small subsite of a larger website, while the second system was a small database designed as part of an exercise by UK university students. Post-design evaluation suggested that the use of both UCA and HTA, rather than one or the other, was beneficial in gathering and analysing user requirements.     

Contextualising design: Aspects of using usability context analysis and hierarchical task analysis for software design

Usability Context Analysis is part of ISO 9241-11 and, as such, is recommended for use in user-centred design. However, studies involving a critical assessment of usability context analysis within the software domain are scarce; this paper details two small studies that involved the use of usability context analysis (UCA) and hierarchical task analysis (HTA). The first system involved designing a small subsite of a larger website, while the second system was a small database designed as part of an exercise by UK university students. Post-design evaluation suggested that the use of both UCA and HTA, rather than one or the other, was beneficial in gathering and analysing user requirements.     

Macroergonomics: analysis and design of work systems

Attending to the larger system components such as organizational design and management is not novel for ergonomists. In Europe, there has been a strong tradition to investigate ergonomic problems within a holistic, systems context. "Macroergonomics" builds upon this tradition by providing specific methods and tools that yield large-scale results. It is believed that meaningful and large-scale results are needed in today's competitive and turbulent work environments. Macroergonomics is defined, its history is uncovered and focus is given to a key methodology, macroergonomic analysis and design. Case studies are used to validate the method and illustrate that performance results in the 60-90% range can be expected.     

Designing sociotechnical systems with cognitive work analysis: putting theory back into practice

Cognitive work analysis (CWA) is a framework of methods for analysing complex sociotechnical systems. However, the translation from the outputs of CWA to design is not straightforward. Sociotechnical systems theory provides values and principles for the design of sociotechnical systems which may offer a theoretically consistent basis for a design approach for use with CWA. This article explores the extent to which CWA and sociotechnical systems theory offer complementary perspectives and presents an abstraction hierarchy (AH), based on a review of literature, that describes an ‘optimal’ CWA and sociotechnical systems theory design system. The optimal AH is used to assess the extent to which current CWA-based design practices, uncovered through a survey of CWA practitioners, aligns with sociotechnical systems theory. Recommendations for a design approach that would support the integration of CWA and sociotechnical systems theory design values and principles are also derived.     

隧道照明系统辅助设计与优化分析软件研发

为提高公路隧道照明系统设计的效率和节能水平,基于IESNA LM-62标准的灯具配光数据文件,并以逐点法为照度和亮度计算方法,在VB.net平台中开发面向公路隧道的照明系统辅助设计与优化分析软件.软件包括的功能有:基于车流量、洞外亮度和运行车速的三因素动态调光、各照明区段的长度与亮度分析、灯具回路设计与模式搜索法安装参...