Ergonomics and human factors: the paradigms for science,engineering, design,technology and management of human-compatible systems

This paper provides a theoretical perspective on human factors and ergonomics (HFE), defined as a unique and independent discipline that focuses on the nature of human-artefact interactions, viewed from the unified perspective of the science, engineering, design, technology and management of human-compatible systems. Such systems include a variety of natural and artificial products, processes and living environments. The distinguishing features of the contemporary HFE discipline and profession are discussed and a concept of ergonomics literacy is proposed. An axiomatic approach to ergonomics design and a universal measure of system-human incompatibility are also introduced. It is concluded that the main focus of the HFE discipline in the 21st century will be the design and management of systems that satisfy human compatibility requirements.     

Human and program factors affecting the maintenance of programs with deployed design patterns

Context

Practitioners may use design patterns to organize program code. Various empirical studies have investigated the effects of pattern deployment and work experience on the effectiveness and efficiency of program maintenance. However, results from these studies are not all consistent. Moreover, these studies have not considered some interesting factors, such as a maintainer’s prior exposure to the program under maintenance.

Objective

This paper aims at identifying what factors may contribute to the productivity of maintainers in the context of making correct software changes when they work on programs with deployed design patterns.

Method

We performed an empirical study involving 118 human subjects with three change tasks on a medium-sized program to explore the possible effects of a suite of six human and program factors on the productivity of maintainers, measured by the time taken to produce a correctly revised program in a course-based setting. The factors we studied include the deployment of design patterns and the presence of pattern-unaware solutions, as well as the maintainer’s prior exposure to design patterns, the subject program and the programming language, and prior work experience.

Results

Among the factors under examination, we find that the deployment of design patterns, prior exposure to the program and the presence of pattern-unaware solutions are strongly correlated with the time taken to correctly complete maintenance tasks. We also report some interesting observations from the experiment.

Conclusion

A new factor, namely, the presence of pattern-unaware solutions, contributes to the efficient completion of maintenance tasks of programs with deployed design patterns. Moreover, we conclude from the study that neither prior exposure to design patterns nor prior exposure to the programming language is supported by sufficient evidences to be significant factors, whereas the subjects’ exposure to the program under maintenance is notably more important.     

The aesthetic and the ethic dimensions of human factors and design

This article discusses the relationship between aesthetics, ethics, and the traditional research issues in human factors, and argues that it is important and beneficial both to the human society and to the human factors profession that we incorporate the aesthetic and the ethic dimensions explicitly and consciously in human factors research and practice. These two dimensions can help us put the current human factors research in a larger context. We can see more clearly the limitations of current research and the needs and challenges for research in new areas. The two dimensions also offer some new perspectives from which we can examine the current work systems and products, explain the demise of old work systems and products, and predict the possible emergence of new work systems and products.     

Timeliness and task specification in designing for human factors in railway operations

Human error is often related to flaws in system design which might have been avoided had greater attention been paid to human factors knowledge and methods as the system was developed. The paper considers the role of human factors in system design and argues that adopting an operational perspective in identifying human factors issues ensures that subsequent human factors advice is focused upon real needs and is consistent with how managers and engineers choose to manage their systems. It also considers the issue of timeliness of human factors input. Failure to consider human factors issues at a time when other design decisions are being taken often means that it is less straightforward to accommodate changes. Thus, managers and engineers may resist dealing effectively with potential human factors problems for reasons of cost and delay in meeting project milestones.     

Evaluating design guidelines for reducing user disorientation in a desktop virtual environment

Navigation in virtual environments can be difficult. One contributing factor is user disorientation. Two major causes of this are the lack of navigation cues in the environment and problems with navigating too close to or through virtual world objects. Previous work has developed guidelines, informed by cinematography conventions, for the construction of virtual environments to aid user comprehension of virtual space to reduce user disorientation. To validate these guidelines, two user studies have been performed where users of a desktop virtual environment are to complete a navigation task in a virtual maze. In an initial study [12], collision detection with the maze walls was not enabled and the results indicated that the guidelines were effective for reducing disorientation but not for developing the users awareness of the environment space. A second study has been performed where collision detection was enabled. Results suggest that the use of the guidelines can help reduce the incidences of user disorientation and aid navigation tasks. However, the guidelines have little impact on users ability to construct cognitive maps of the desktop virtual environment.

Integrating human factors in freight interoperability safety design

According to European Directives, it would be necessary to develop freight interoperability, defined as crossing borders from one country to another without changing either locomotive or driving crew. This project is a challenge for the railway companies that control infrastructures and traffic. The interoperability implementation implies changes in work techniques, regulation and organisation, that may affect the reliability of the systems involved, giving rise to risky situations in terms of production, regularity and safety. The purpose of this paper is to describe a proactive ergonomic approach used for the integration of human factors and safety at the early stages of design for future interoperable situations. Ergonomic analysis has been oriented within a socio-technical frame where a workstation is viewed in its technical and organisational dimensions. Three methods have been used: observations in marshalling yards and driving cabin in other countries, staff interviews and analyses of incidents and hazards. Results formed the basis for developing “a methodological guide for integrating human factors”. In a more general way, some principles for an ecological design of a safe organisational system are provided in the last section of this paper.

Supporting a distributed execution of clinical guidelines

Clinical guidelines (GL) play an important role in medical practice: the one of optimizing the quality of patient care on the basis of evidence based medicine. In order to achieve this goal, the interaction between different agents, who cooperate in the execution of the same GL, is a crucial issue. As a matter of fact, in many cases (e.g. in chronic disorders) the GL execution requires that patient treatment is not performed/completed in the hospital, but is continued in different contexts (e.g. at home, or in the general practitioner's ambulatory), under the responsibility of different agents. In this situation, the correct interaction and communication between the agents themselves is critical for the quality of care, and human resources coordination is a key issue to be addressed by the managers of the involved healthcare services. In this paper we describe how GLARE (Guideline Acquisition, Representation, and Execution), a computerized GL management system, has been extended in order to support such a need. In particular, we have provided: (i) an extension to GL actions representation languages, (ii) proper scheduling and (iii) querying services. By means of these enhancements we aimed at guaranteeing (1) treatment continuity and (2) responsibility assignment support in the various steps of a coordinated and distributed patient care process. We illustrate our approach by means of a practical case study.     

A systematic approach to the development of research-based web design guidelines for older people

This paper presents a systematic approach to the development of a set of research-based ageing-centred web design guidelines (SilverWeb Guidelines). The approach included an initial extensive literature review in the area of human–computer interaction and ageing, the development of an initial set of guidelines based on the reviewed literature, a card sorting exercise for their classification, an affinity diagramming exercise for the reduction and further finalisation of the guidelines, and finally a set of heuristic evaluations for the validation and test of robustness of the guidelines. The 38 final guidelines are grouped into eleven distinct categories (target design, use of graphics, navigation, browser window features, content layout design, links, user cognitive design, use of colour and background, text design, search engine, user feedback and support).     

Evidence-based guidelines for the wise use of computers by children: Physical development guidelines

Computer use by children is common and there is concern over the potential impact of this exposure on child physical development. Recently principles for child-specific evidence-based guidelines for wise use of computers have been published and these included one concerning the facilitation of appropriate physical development. This paper reviews the evidence and presents detailed guidelines for this principle. The guidelines include encouraging a mix of sedentary and whole body movement tasks, encouraging reasonable postures during computing tasks through workstation, chair, desk, display and input device selection and adjustment and special issues regarding notebook computer use and carriage, computing skills and responding to discomfort. The evidence limitations highlight opportunities for future research. The guidelines themselves can inform parents and teachers, equipment designers and suppliers and form the basis of content for teaching children the wise use of computers.

Statement of Relevance: Many children use computers and computer-use habits formed in childhood may track into adulthood. Therefore child–computer interaction needs to be carefully managed. These guidelines inform those responsible for children to assist in the wise use of computers.     

Assessing the value of human factors initiatives

This paper examines the effectiveness of human factors initiatives and addresses some difficulties reported in calculating the value of such interventions. Company representatives and researchers applied a novel probabilistic assessment tool to estimate the financial impact of two macro-ergonomic projects. Key benefits of the company intranet project include reduced administrative and operational costs compared to a paper-based system; time savings for users asking for, providing and receiving information; and improved system usability and higher levels of usage. The communities of practice project demonstrates value through more efficient distribution and retrieval of information; reduced duplication by re-using technical knowledge to solve similar problems and improved sharing of good working practices, lessons and resources. The strengths of the tool include transparency, being quick and easy to learn and the collaborative workshop format, involving researches and key representatives from the organization. It makes a useful contribution to the challenge of assessing the financial value of ergonomic interventions, and, by exploiting its diagnostic and planning capabilities, could be extended to other domains.     

Towards a capabilities database to inform inclusive design: experimental investigation of effective survey-based predictors of human-product interaction

A key issue in the field of inclusive design is the ability to provide designers with an understanding of people's range of capabilities. Since it is not feasible to assess product interactions with a large sample, this paper assesses a range of proxy measures of design-relevant capabilities. It describes a study that was conducted to identify which measures provide the best prediction of people's abilities to use a range of products. A detailed investigation with 100 respondents aged 50-80 years was undertaken to examine how they manage typical household products. Predictor variables included self-report and performance measures across a variety of capabilities (vision, hearing, dexterity and cognitive function), component activities used in product interactions (e.g. using a remote control, touch screen) and psychological characteristics (e.g. self-efficacy, confidence with using electronic devices). Results showed, as expected, a higher prevalence of visual, hearing, dexterity, cognitive and product interaction difficulties in the 65-80 age group. Regression analyses showed that, in addition to age, performance measures of vision (acuity, contrast sensitivity) and hearing (hearing threshold) and self-report and performance measures of component activities are strong predictors of successful product interactions. These findings will guide the choice of measures to be used in a subsequent national survey of design-relevant capabilities, which will lead to the creation of a capability database. This will be converted into a tool for designers to understand the implications of their design decisions, so that they can design products in a more inclusive way.     

Developing human factors/ergonomics as a design discipline

This paper deals with internal challenges that the human factors/ergonomics (HFE) research faces when wishing to strengthen its contribution to development of work systems. Three established characteristics of high-quality HFE, i.e., HFE takes a systems approach, HFE is design-driven, and HFE focuses on two closely related outcomes, performance and well-being, are taken as a starting point of a methodological discussion, in which conceptual innovations, e.g. adopting the technology-in-use perspective, are proposed to support development of HFE towards the high-quality aims. The feasibility of the proposed conceptual choices is demonstrated by introducing a naturalistic HFE analysis approach including four HFE functions. The gained experience of the use of this approach in a number of complex work domains allows the conclusion that becoming design-driven appears as that most difficult quality target for HFE to reach. Creating an own design discipline identity in a multi-voiced collaboration is the key internal challenge for human factors/ergonomics.     

Workplace design guidelines for asymptomatic vs. low-back-injured workers

While numerous efforts have attempted to provide quantitative guidelines for the prevention of initial low back disorders during material handling tasks, none have appeared in the literature that address the issue of recurrent low back disorders due to materials handling when returning to the workplace. A study comparing the spine loads of low back pain patients and asymptomatic controls was conducted. Subjects lifted weights varying from 4.5-11.4 kg at four vertical heights, two horizontal distances and five task asymmetries collectively representing common industrial lifting situations. Spine loading was calculated using a validated EMG-assisted biomechanical model. Spine loads observed during lifting tasks were compared to spine tolerance values believed to initiate low back injuries. In addition, the percentage of patients successfully performing the lift was noted and used as an indication of the willingness of the subject to perform the task. These evaluations are summarized in a series of three lifting guidelines indicating safe, medium risk and high risk lifting tasks for low back patients as well as asymptomatic workers. It is believed that adherence to these guidelines can minimize the risk of recurrent low back disorders due to occupational lifting.     

The role of human factors engineering in establishing occupational fitness standards

Human factors engineering (HFE) is the study of the impact of workplace design, and workplace environment, on people and includes those issues that have an impact on the body's structure and functioning. The goal of HFE is to assure the personal health, wellness and safety of people in their workplace, while enhancing their productivity. In recent history there have been cases in which an employee has been dismissed from their job for failing the physical requirements test portion of the job. This is particularly prevalent in industries that require significant strength capacities which until recently have been traditionally male dominated. There is still a need to implement test procedures, which define task requirements in terms of psychomotor ability and physiological capacity rather than the limited measures of aerobic power or muscular strength. This paper examines the current practices used to develop job task requirements in the traditionally male-dominated occupations of firefighter, police officer and armed forces personnel and the role of task analysis. A case study of a local firefighting unit is presented in the context of task analysis.     

The design and use of the TMiner component-based data mining framework

This paper provides some practical guidelines for the design of data mining frameworks. It describes the rationale behind some of the key design decisions that guided the design, development, and implementation of the TMiner component-based data mining framework. TMiner is a flexible framework that can be used as a stand-alone tool or integrated into larger business intelligence (BI) solutions. TMiner is a general-purpose component-based system designed to support the whole KDD process into a single framework and thus facilitate the implementation of complex data mining scenarios.     

An evaluation methodology for crowdsourced design

In recent years, the “power of the crowd” has been repeatedly demonstrated and various Internet platforms have been used to support applications of collaborative intelligence in tasks ranging from open innovation to image analysis. However, crowdsourcing applications in the fields of design research and creative innovation have been much slower to emerge. So, although there have been reports of systems and researchers using Internet crowdsourcing to carry out generative design, there are still many gaps in knowledge about the capability and limitations of the technology. Indeed the process models developed to support traditional commercial design (e.g. Pugh’s Total Design, Agile, Double-Diamond etc.) have yet to be established for Crowdsourced Design (cDesign). As a contribution to the development of such a general model this paper proposes a cDesign framework to support the creation of crowdsourced design activities. Within the cDesign framework the effective evaluation of design quality is identified as a key component that not only enables the leveraging of a large, virtual workforce’s creative activities but is also fundamental to almost all iterative optimisation processes. This paper reports an experimental investigation into two different Crowdsourced design evaluation approaches; free evaluation and ‘Crowdsourced Design Evaluation Criteria’ (cDEC). The results are benchmarked against a ‘manual’ evaluation carried out by a panel of experienced designers. The results suggest that the cDEC approach produces design rankings that correlate strongly with the judgements of an “expert panel”. The paper concludes that cDEC assessment methodology demonstrates how Crowdsourcing can be effectively used to evaluate, as well as generate, new design solutions.     

Human factors in information technology: The socio-organisational aspects of expert systems design

This paper looks beyond the mostly technical and business issues that currently inform the design of knowledge-based systems (e.g., expert systems) to point out that there is also a social and organisational (a socio-organisational) dimension to the issues affecting the design decisions of expert systems and other information technologies. It argues that whilst technical and business issues are considered before the design of Expert Systems, that socio-organisational issues determine the acceptance and long-run utility of the technology after it has been implemented. It shows how four issues within the organisation can affect the design or the after-effects of the design and implementation of the technology. It also shows how the four issues can be considered within the structured phases of expert system development.     

Research-based guidelines for warning design and evaluation

During the past two decades, the body of empirical research on warning design and evaluation has grown. Consequently, there are now basic principles and guidelines addressing warning design (e.g., signal words, color, symbols, and text/content), placement (e.g., location within product instructions), and how to enhance the usability of designs by considering factors internal to the user (e.g., beliefs, perceptions of risk, stress). Similarly, evaluation methods have been developed that can be used to measure the effectiveness of warnings such as the degree to which warnings are communicated to recipients and the degree to which they encourage or influence behavioral compliance. An overview of the empirical literature on warning guidelines and evaluation approaches is provided. Researchers, practitioners, and manufacturers can use these guidelines in various contexts to reduce the likelihood that injury and product damage from exposure to a hazard will occur.