A methodology for evaluating the usability of audiovisual consumer electronic products

Usability evaluation is now considered an essential procedure in consumer product development. Many studies have been conducted to develop various techniques and methods of usability evaluation hoping to help the evaluators choose appropriate methods. However, planning and conducting usability evaluation requires considerations of a number of factors surrounding the evaluation process including the product, user, activity, and environmental characteristics. In this perspective, this study suggested a new methodology of usability evaluation through a simple, structured framework. The framework was outlined by three major components: the interface features of a product as design variables, the evaluation context consisting of user, product, activity, and environment as context variables, and the usability measures as dependent variables. Based on this framework, this study established methods to specify the product interface features, to define evaluation context, and to measure usability. The effectiveness of this methodology was demonstrated through case studies in which the usability of audiovisual products was evaluated by using the methods developed in this study. This study is expected to help the usability practitioners in consumer electronics industry in various ways. Most directly, it supports the evaluators' plan and conduct usability evaluation sessions in a systematic and structured manner. In addition, it can be applied to other categories of consumer products (such as appliances, automobiles, communication devices, etc.) with minor modifications as necessary.     

Ecological performance of electrical consumer products: the influence of automation and information-based measures

Being concerned with the environmental impact of electrical consumer products, this article examines possibilities of influencing ecological user performance through design features. Furthermore, it looks at the relationship of user characteristics and ecological performance. The impact of level of automation and type of control labelling on ecological user performance was examined in a lab-based experimental scenario with 36 users. In addition to performance indicators, a range of user variables (e.g., self-reported domestic behaviour, environmental knowledge and attitude) was measured to assess their influence on user behaviour. The results showed that low-level automation improved ecological performance whereas no such positive effect was observed for enhanced display-control labelling. Furthermore, the results suggested that the user's mental model of ecological performance was rather limited. No relationship was found between environmental knowledge, attitude and performance. The findings pointed at the strong prevalence of habits in the domestic domain. The implications of the results for designers of consumer products are discussed.     

一种基于缴费积极性的电力客户信用评估模型

对客户进行电信用评估是电力公司实现营销精益化管理的重要任务,现有相关方法较多地依赖经验规则确定评估模型,研究提出了基于电力客户缴费积极性的信用值定量化评估新模型。首先提出以加权正则化付费周期值衡量客户缴费积极性,随后基于理论分析及客户真实缴费数据推断获得评估模型,不依赖主观经验地实现了电力客户缴费信用值的连续量化评估。理论及实验分析表明,新方法具备较好的理论依据及真实数据分析结果的支撑,能够合理有效地量化反映客户的电力消费信用。     

Visual product evaluation: exploring users' emotional relationships with products

This paper discusses an industrial designer's approach to eliciting user perceptions and emotional responses to products through visual evaluation and stimuli. Whilst the authors accept that product functionality is crucial for product success, the appearance, use of materials, shape and form provide the most immediate product data for the user. Less tangible issues such as emotional bonding of users with products, cultural perceptions and social value systems, provide valuable insights for the product developer to help expand knowledge and understanding of the users' need beyond the functional. This paper presents product personality profiling as a new technique for design researchers/designers, and discusses it alongside other emerging approaches such as mood boards and visual product evaluation. The authors have used these techniques during focus group sessions with users to elicit individuals' needs and aspirations towards products. Such a user-centred approach is fundamental to applied ergonomics. Experiences, benefits, and limitations of these techniques are outlined as well as the opportunities for further development.     

Survey instrument for the universal design of consumer products

Universal design is a process intended to include all user groups in product or environmental design. The objective of this study was to develop a usability testing survey instrument to inform how well consumer products complied with established principles of universal design. Thirty-six adults, aging adults and adult wheelchair users performed standardized tasks with pens, food storage containers, pliers and calculators, and for each task responded to a preliminary set of survey items and rated task difficulty. Factor analysis of the survey responses produced an eleven-factor solution that accounted for 67% of the variance in scores and corresponded fairly closely to the principles of universal design. Analysis of scale scores developed from each factor showed that some of the scales were sensitive to product feature and user group differences, and were negatively associated with perceived task difficulty. Such a tool may aid designers who intend their products for user groups of diverse abilities and preferences.     

Parallel algorithms for rounding exact evaluation of sums of products

We propose two parallel algorithms for the rounding exact evaluation of sums of products. The first method transforms products to sums and applies one of the known methods for rounding exact summation in time complexity O(n²) with n processors (n denoting the “length” of the expression). The second method approximates the products as well as the sum and has average time complexity O(ld(n)) for n/2 processors and has average time complexity O(n) viewed as a sequential algorithm.     

‘1966 and all that’: Trends and developments in UK ergonomics during the 1960s

The 1960s represents a key decade in the expansion of ergonomics within the UK. This paper reviews trends and developments that emerged out of the 1960s and compares these with ergonomics research and practice today. The focus in particular is on the expansion of ergonomics as a discipline within industry, as well as more specific topics, such as the emergence of areas of interest, for example, computers and technology, automation and systems ergonomics and consumer ergonomics. The account is illustrated with a detailed timeline of developments, a set of industrial case studies and the contents of important publications during the decade. A key aim of the paper is to provide the opportunity to reflect on the past and the implications this may have for future directions for ergonomics within the UK.

The paper provides practitioners with an insight into the development of ergonomics in the UK during one of the most important decades of its history. This is especially relevant given the fact that in 2009 the Ergonomics Society celebrates its 60th anniversary.     

面向家电产品的人机工程分析与评价系统

结合家电产品的人机特性开发了一个人机工程分析与评价系统．该系统能够建立虚拟人机环境,对舒适度、可及范围、姿势预测、静态受力分析等多个指标进行动态分析和评价．实验结果表明,该系统能够对吸尘器、摩托车以及冰箱等家电产品的人机特性进行定量分析与评价,给设计师提供反馈修改建议,支持产品创新．     

Corporate-internal vs. national standard – A comparison study of two ergonomics evaluation procedures used in automotive manufacturing

Manufacturing corporations sometimes use corporate-internal procedures to evaluate and monitor the ergonomic status of the workplace. This article describes an industrial case study in the Swedish automotive sector, where an internally developed evaluation procedure was compared with a procedure based on a Swedish national standard provision.It was found that the national standard procedure tended to give more severe ratings and statistical support shows that the two evaluation procedures are not equivalent. The ability of the methods to identify body segments at risk was also compared.The quantitative comparison was followed up with interviews, where the influence of professional tasks and objectives became evident, as well as the fact that evaluation criteria are quantified differently by the two procedures. The main finding is that unforeseen differences in analysis procedure, criteria of acceptability and levels of detail can cause use-related difficulties for different professional groups when methods are used interchangeably.

Relevance to industry

Industrial corporations wishing to monitor ergonomics consistently are advised by the authors to ensure that ratings from internal evaluations are interpreted the same way by all involved personnel, and that they at least have criteria levels equivalent to those of a national standard.     

战斗机座舱人机工效评价方法研究

提出了一种基于灰色系统理论多属性群决策方法的战斗机座舱人机工效评价方法,通过建立战斗机驾驶座舱人机工效评价体系,研究了人的因素和机的因素,在对战斗机座舱人机工效分析的基础上,确定了评价因素,建立合适的评价指标体系,结合上述方法确定了合理的评价步骤,并进行了推理和验证。     

Quality disclosure strategy in a decentralized supply chain with consumer returns

We study the quality disclosure strategy of a manufacturer/retailer in a supply chain with consumer returns for new products. In particular, we explicitly model the effect of quality disclosure on the reduction of the returns rate. We identify the condition in which the manufacturer/retailer should reveal product quality in the presence of consumer returns. We find that (1) the manufacturer/retailer has an incentive to choose quality disclosure strategy when the disclosure quality is above a lower bound; (2) if the returns rate of new products is low, the retailer‐disclosure scenario leads to reveal more quality information than that of the manufacturer‐disclosure scenario; otherwise, the manufacturer‐disclosure scenario leads to reveal more quality information; and (3) the manufacturer prefers to reveal a higher level of product quality in the supply chain with a higher refund amount or a lower salvage value per unit of returned product.     

Product lines for digital information products

The growth of the Web has fueled the creation, storage, and exchange of digital information products (DIPs), whose main purpose is the delivery of information, entertainment, education, or training. Very often, after their initial creation, the growing amount of content also leads to a more complicated maintenance, since updates typically occur rather often and the potential variability of modifications is not limited in advance. Moreover, commonalities between different parts of similar information products are not exploited, which often leads to redundancy. At the moment, there is hardly any attempt to compose information products from different sources and to produce more complex information products in a coordinated way. To help remedy this situation, this paper introduces the Product Lines for digitAl iNformation producTs (PLANT) approach, which applies the concept of software product lines to DIPs. The PLANT approach explicitly manages the commonalities of similar DIPs by defining common requirements, limiting variability in advance, as well as planning and coordinating reuse. This article focuses on the modeling of such product lines. In particular, the developed general concepts will be exemplified throughout the paper in the area of e-learning, in which DIPs play an important role. The application of PLANT in other areas and an implemented tool that supports the creation of information products in a product line are outlined as well.     

The process evaluation of two alternative participatory ergonomics intervention strategies for construction companies

To gain insight into the process of applying two guidance strategies – face-to-face (F2F) or e-guidance strategy (EC) – of a Participatory Ergonomics (PE) intervention and whether differences between these guidance strategies occur, 12 construction companies were randomly assigned to a strategy. The process evaluation contained reach, dose delivered, dose received, precision, competence, satisfaction and behavioural change of individual workers. Data were assessed by logbooks, and questionnaires and interviews at baseline and/or after six months. Reach was low (1%). Dose delivered (F2F: 63%; EC: 44%), received (F2F: 42%; EC: 16%) were not sufficient. The precision and competence were sufficient for both strategies and satisfaction was strongly affected by dose received. For behavioural change, knowledge (F2F) and culture (EC) changed positively within companies. Neither strategy was delivered as intended. Compliance to the intervention was low, especially for EC. Starting with a face-to-face meeting might lead to higher compliance, especially in the EC group.

Practitioner Summary: This study showed that compliance to a face-to-face and an e-guidance strategy is low. To improve the compliance, it is advised to start with a face-to-face meeting to see which parts of the intervention are needed and which guidance strategy can be used for these parts.

Trial registration: ISRCTN73075751     

Portability of three consumer products

Three consumer products (a television set, a personal computer and a typewriter), all considered portable by their respective manufacturers, were evaluated experimentally for portability. Products were not considered portable if the physical and subjective workloads resulting from carrying them over specified distances were excessive. Twenty-two males and six females participated in the experimental investigation and carried the three products for distances of 45·72, 91·44. 137·16 and 182·88 m. Their pulse and ratings of perceived exertion (RPE) of the arms and whole body were recorded and used as measures of physical and perceived workloads. Both physiological and subjective responses to carrying products were significantly influenced by the type of product and carrying distance, regardless of the gender of the person performing the carrying. The results of this study and the design guidelines provided in the literature for one-handed and two-handed carrying tasks led to the conclusion that, of the three products, only the television set could be considered portable.     

Representing older and disabled people in virtual user trials: data collection methods

A database was developed to support the creation of a computer-based tool which will support design teams in evaluating the usability of a design during early prototyping and indicate which individuals are effectively excluded or designed out. Methods are described for the collection of multivariate data on 100 real individuals covering a range of physical characteristics and capabilities. These data were tested to ensure a breadth of representation of individuals (particularly older and disabled people) in terms of anthropometry, joint constraints, postural capabilities and task behaviours. The concept of the design tool itself is explored by conducting virtual user trials in the computer-aided design environment. The novel approach of the research encourages empathy with individual users and allows generic abilities, such as bending, reaching and lifting to be assessed.     

考虑消费者效用的电商平台信用支付决策研究

考虑由两个生产不同质量产品的制造商和一个电商平台组成的供应链,基于消费者剩余理论,研究电商平台的信用支付服务决策问题。基于消费者选择不同支付方式购买产品的消费者效用,建立电商平台收益模型,进一步分析得到平台的信用支付服务决策。研究表明,当消费者对质量一般产品的接受程度较高、信用支付服务对消费者带来的负效应较大时,推出信用支付可以提高平台收益,增加消费者剩余;当消费者对质量一般产品的接受程度较低、信用支付服务的负效应较小时,推出信用支付服务且设置较长的延迟支付期可提高平台收益,增加消费者剩余,否则将产生较大资金成本,使平台利益受损。电商平台可通过制定合理的信用支付策略提高平台收益。     

聚类算法在电信客户细分中的应用研究

结合聚类算法的分析,提出了一种解决电信客户细分的应用模型,该模型在实际中得到了较好的应用并为电信服务产品的策划设计提供了依据。同时,通过引入指标区分度的定义,给出了一种聚类方法应用效果评估的方法。该方法结合电信的案例应用与K-Means、SOM、BIRCH等聚类方法结果的分析,得出K-Means方法在电信客户市场细分中的应用优越性。     

Surveying the dimensions and characteristics of Korean ears for the ergonomic design of ear-related products

Six hundred male and female Korean subjects aged 17–89 were selected for this study. Four different points of the outer ear—the lengths of the pinna, the ear connection point, the earhole and the lobule thickness—were measured and analyzed along with demographic data, including age, stature and weight. The results showed that age, sex and different ethnic populations were determinants of ear dimensions as exemplified by the length of the pinna which increases as age increases (r=0.689). The primary objective of this study was to provide product designers with the anthropometric dimensions of Korean ears and recommend appropriate solutions for the ergonomic design of ear-related products. Based on the results of this study, it is recommended that the change in body parts due to aging be considered in the application of anthropometric data when designing such products.

Relevance to Industry

Limited research has been done on the dimensions of ears although an extensive amount of research has been conducted on other parts of the human body. The findings of this study, therefore, can be used as a basis for researching and producing ergonomically designed ear-related products.     

Participatory ergonomics in design processes: the role of boundary objects

The aim of this paper is to introduce the concept of boundary objects in order to better understand the role of objects in participatory ergonomics (PE) design processes. The research question is: What characterizes boundary objects in PE processes? Based on two case studies, we identify eight characteristics of boundary objects and their use, which make them particularly useful in PE design processes. These characteristics go beyond the object itself and extend into the context of their use. We argue that the selection of boundary objects in PE processes is of great importance, since different objects enable workers’ participation and collaborative design in different ways. The framework developed may serve to provide criteria to guide practitioners and intervention researchers in the selection of objects to facilitate a PE process. The paper concludes with a list of recommendations for ergonomic practitioners that are based on the framework.     

Design evaluation and modification of mechanical systems in virtual environments

Design is one of the most important stages in the manufacturing cycle and influences all the subsequent stages of product development. In the context of today’s iterative design methodology, the modification of any design is a process involving many evaluations and improvements to the solutions chosen in earlier stages. For this purpose, in the most recent decade, 3D computer simulations have become common tools used within industry. Whilst virtual reality (VR) technology is seen as the interaction technology of the future, much of the current research in this area is carried out to explore the potential benefits and added value brought by the integration of this into standard software technologies currently used at various stages in manufacturing life cycle. A lot of attention has been given to exploring the usability and benefits of interactive VR for assembly planning, knowledge elicitation and design and simulation. However, little research has focussed on the analytical aspects of the design process, for example in the use of VR as an interface for simulation software in finite element methods and multi-body systems. This paper introduces research focussing on applications of virtual environments (VEs) for interactive design evaluation and modification adapted and used with standard simulation software. The use of such interactive visualisation offers the engineer more realistic real-time representations of the design and advanced facilities to interact with the model during the design process. While design evaluation is based mainly on visualisation; design modification requires interactive changes of the model during the simulation, and the interfaces described here highlights such applications. In this work, two software prototypes have been developed using VR technology. First, a software tool called design evaluation in virtual environments is presented together with an application in civil engineering to illustrate the mode of operation and added value of the use of an interactive visualisation environment. Linking the simulation software with the VE provides real time bi-directional communication of graphical information which can be successfully achieved even within the limits of current computer technology. The tool includes a suite of software modules and a user interface to facilitate the link between the simulation results and the VE. The second tool facilitates the design modification in virtual environments system by providing real time dynamic simulation. Two dynamic approaches are investigated in order to study the real time simulation issues in the context of design modification and system performance: the classic approach based on rigid interconnected bodies, and a new and novel approach developed by the authors based on particles dynamics. Both implementations have been tested and compared on a mechanism application under the same computing conditions. The research applications presented demonstrate the practicality, flexibility and versatility of the visualisation in virtual environment in design evaluation and modification. However, the computer efficiency whilst carrying out real time dynamic simulation is limiting the range of applications to models of moderate size; however, this is an improvement on previous similar applications.