• The Journal of Society for e-Business Studies
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• v.6 no.2
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• pp.73-85
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• 2001

Usability is defined by the effectiveness, efficiency and satisfaction with which specified users can achieve specified goal in particular environment. Today, many factors such as software acquisition, business re-engineering and the trend of software market have software industry considers usability as an important quality of software products. Therefore, the specification and measurement method for establishing the acceptable usability level of software is required during software development acquisition and evaluation. To evaluate whether software products is usable or not, we need evaluation method for software usability. This paper is not only to provide a framework for specifying the usability attributes of a product and establishing a comprehensive set of usability criteria, but also assessing usability metrics of the software. The usability metrics and checklist is developed based on the properties of the user interface using ISO standard and general usability principles with product-oriented view which means the Product has attributes contributing to determine the usability. This paper also suggested the way to weight the relative importance of the individual usability item depending on the software categories.

• Journal of Information Technology Services
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• v.7 no.4
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• pp.179-198
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• 2008

It is widely known that usability is a critical quality attribute of IT systems. Many studies have developed various methods for finding out usability problems. Usability professionals have emphasized that usability should be integrated into the development life cycle in order to maximize the usability of systems with minimal cost. To achieve this, it is essential to classify usability problems systematically and connect them into the activities of designing user interfaces and tasks. However, there is a lack of framework or method for these two problems and thus remains a challengeable research issue. As a beginning study, this paper proposes a conceptual framework for addressing the two issues. We firstly summarize usability-related studies so far, including usability factors and evaluation methods. Secondly, we review seven approaches to identifying and classifying usability problems. Based on this review and opinions of usability engineers in real industry as well as the review results, this paper proposes a framework comprising three viewpoints, from which more sound classification scheme of usability problems can be inductively developed.

• Journal of Information Technology Applications and Management
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• v.25 no.3
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• pp.17-28
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• 2018

In this paper, an activity-oriented usability model is proposed. The usability model contains two types of characteristics: special-type characteristics of usability and sub-characteristics of usability. Workability, study-ability, and playability are, but do not exhaust, examples of special-type characteristic of usability. They correspond to working, studying, and playing using the software product, respectively. They represent the goal of using and can overlap each other. They are usability too by themselves. Navigate-ability, data-prepare-ability, data-input-ability, response-wait-ability, output-examine-ability, and output-utilize-ability are typical examples of sub-characteristics of usability. They correspond to navigating, preparing data, inputting data, waiting response, examining output, and utilizing the output data, respectively. They are not usability by themselves. They constitute usability together as a group. Assessing is the fundamental and indispensable aspect of quality. Without assessing, the concept of quality has little practical value. Satisfaction, effectiveness, and efficiency are the most typical sub-characteristics of usability in existing quality models, which correspond to the evaluation criteria of usability. In the activity-oriented usability model, however, only the user's satisfaction is included: Satisfaction is regarded as the operational definition of usability in the user's view. As the result, usability can be interpreted as the 'goodness for using, which is evaluated by the user. 'Three fundamental principles regarding software quality models are proposed too in this paper: Principles of Parsimony, Cohesiveness, and Inheritance. Discussions illustrate well that typical existing usability models violate these basic principles. Many authors have tried to define general usability models which can be applied to most kinds of software. The dream of the general and universal usability model, however, may be an illusion. The activity-oriented usability model is expected to serve as a prototype from which specialized usability models can be derived.

• Science of Emotion and Sensibility
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• v.14 no.1
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• pp.83-92
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• 2011

Because of the development of digital technologies and information-oriented products, the importance of user interface design and usability are increasing in recent year. So we need a systematic and rational way to measure and manage how effective the improvement of user interface is. The purpose of this study is to develop measurable ‘Usability Improvement Index' which signify how much usability has improved in user interface design. First, I made the framework of measuring and evaluating usability through analysis of existing usability metrics and previous studies. Then, I suggested the process of calculating 'Usability Improvement Index' based on categorizing characteristics of measurable usability and definition of usability metrics. The process is as in the following : measuring the present level of usability, analysis of problems, making alternative user interface design, measuring the improved level of usability, calculating Usability Improvement Index. For verification, the case study on application of Usability Improvement Index to usability improvement of application software of digital camcorder presented. This study is expected to assist 'goal oriented user interface design' and to manage usability systematically.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2003.11a
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• pp.1241-1242
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• 2003

본 연구는 Usability의 투자 성과관리(ROI: Return On Investment)를 위한 균형성과지표(BSC: Balanced ScoreCard) 관점에서의 Framework 개발을 목표로 한다. 2000년 이후 Usability에 대한 투자 규모는 높은 증가세를 유지해 왔으나 대규모 투자가 진전되는 가운데 Usability투자의 수익성을 어떻게 확보하고, 그 효과(Effectiveness)는 어떻게 측정할 것인가 하는 문제는 상대적으로 관심을 끌지 못하고 있다. Usability 투자에 대한 시스템적 성과관리를 위해 개발된 Usability BSC Framework은 BSC의 4가지 관점에서 Usability 투자성과관리에 대한 변형된 관점의 모델을 제안한다.

• Journal of The Korean Society of Integrative Medicine
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• v.6 no.3
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• pp.83-92
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• 2018

Purpose : The purpose of this study was to develop an index of usability that reflects the needs and characteristics of the elderly. The usability index is used primarily to assess issues in the usability of a product. Methods : In this study, 22 items for mobile toilet usability index were developed by consulting with 12 elderly users, 6 caregivers, and 12 experts. The usability evaluation index was intended to increase reliability through preliminary and main evaluations. In addition, the validity of the items used as the usability evaluation index was verified to prove that the index is effective for the evaluation. Result : The usability index is a welfare tool developed by gathering data from various sources such as previous studies dealing with usability evaluation, characteristics of users, range of use, and environment of product use. Conclusion : The development of the usability index for mobile toilets was useful for the user to quantitatively derive the problem of the product. Consequently, user needs and usability problems can be identified, which can help improve product quality.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.909-917
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• 2006

In the last decade, the research of the usability of mobile phones has been a newly evolving area with few established methodologies and realistic practices that ensure capturing usability in evaluation. Thus, there exists growing demand to explore appropriate evaluation methodologies that evaluate the usability of mobile phones quickly as well as comprehensively. This study aims to develop a task-based usability checklist based on heuristic evaluations in views of mobile phone UI practitioners. A hierarchical structure of UI design elements and usability principles related to mobile phones were developed and then utilized to develop the checklist. In order to demonstrate the practical effectiveness of the proposed checklist, comparative experiments were conducted on the usability checklist and usability testing. Majority of usability problems found by usability testing and additional problems were discovered by the proposed checklist. It is expected that the usability checklist proposed in this study could be used quickly and efficiently by usability practitioners to evaluate the mobile phone UI in the middle of the mobile phone development process.

• Journal of Korean Institute of Industrial Engineers
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• v.32 no.2
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• pp.111-119
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• 2006

In the last decade, the research of the usability of mobile phones has been a newly evolving area with few established methodologies and realistic practices that ensure capturing usability in evaluation. Thus, there exists a growing demand to explore appropriate evaluation methodologies that evaluate the usability of mobile phones quickly as well as comprehensively. This study aims to develop a task-based usability checklist based on heuristic evaluation in views of mobile phone UI practitioners. A hierarchical structure of UI design elements and usability principles related to mobile phones were developed and then utilized to develop the checklist. In order to demonstrate the practical effectiveness of the proposed checklist, comparative experiments were conducted on the usability checklist and usability testing. A majority of usability problems found by usability testing and additional problems were discovered by the proposed checklist. It is expected that the usability checklist proposed in this study could be used quickly and efficiently by usability practitioners to evaluate the mobile phone UI in the middle of the mobile phone development process.

• Journal of the Ergonomics Society of Korea
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• v.29 no.6
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• pp.843-851
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• 2010

This study aims to systematically develop a usability evaluation model using the Structural Equation Model (SEM) from experiment of usability on using vehicle. Vehicle developers have been adding many functions for enhance the user satisfaction. But it will be made the trade-off problem of usability and design elements of vehicle interior from attempt to make best usability satisfaction in a restricted space. To solve the trade-off problem, we set a new solution criterion from usability evaluation model. The usability experiment is based on major activity pool from derived user's acts pattern in vehicle for make more accurate usability evaluation model. And this model was built with twenty-nine measurement variables for the evaluation of usability of vehicle user. As a result, the proposed SEM model showed statistical significance as well as a high level of R Square (0.7144). This model shows the relationships of detailed usability and design elements. According to the result, this study introduces the criterion to secure the best satisfaction of usability and design elements.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.17 no.30
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• pp.177-184
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• 1994

The importance of usability evaluation is increasing in developing the system(or product). Many usability measures and test methods have been developed in the fields of ergonomics and cognitive engineering. A systematic usability effort using established methods may be qualify as usability engineering. In this paper, general aspects of the usability engineering are introduced, and application methods of usability engineering model based on product's life cycle are presented.