The concept of universal design has recently emerged as an important aspect of product design. Universal design is considerably analogous to ergonomic design in a way that it takes the capabilities and limitations of users into consideration during the product development process. However, relatively few studies have been devoted to reflect the practical use of ergonomic principles on universal design. This research attempts to develop a universal design index for automobile interior design to quantify how well a product complies with principles of universal design. The research also emphasizes on ergonomic principles as a basis of evaluation. A generation of the index was done by cross-checking among the personal, activity and product components drawn from the scenarios of vehicle use. Personal components consist of human characteristics including age, physique, perceptual capacity, reach, etc.. Activity components were derived from those scenarios of vehicle use while product components were composed of interior parts to which a user interacts. Further analysis systematically generated an universal index from relationship matrices among the three components. The index was then used to test its suitability by applying to the evaluation of passenger cars currently on the market. This study demonstrates a development process through which evaluations can be made possible for universal design. The research suggests an improved approach to the appraisal of how well cars are universally designed based on ergonomic principles.

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To provide ready-to-use information for wheelchair users accessing Kamakura, an internationally famed tourist city, accessibility of streets and shops along three main tourist streets was studied. The study comprised three stages: (a) investigation of the accessibility of streets and shops along them, (b) interviews of wheelchair users about their experiences, and (c) design of a new barrier-free road map for wheel-chaired visitors. In addition to the street conditions such as unevenness, road signs and multi-purpose toilets, the accessibility of the entrance conditions of all the shops along these streets was investigated in 2003 and 2005. Height differences of 2cm or more at the entrance were found in over 60% of shops along the two of the three routes. The rate of shops accessible for wheelchair visitors along two shop streets was only 31 and 34%, respectively, compared with 50% along a main avenue. Shops becoming accessible during the period from 2003 accounted for only 4%, 0% and 3%, respectively. The wheelchair users interviewed confirmed the low level of accessibility of streets and shops in the city. Based on the results. a barrier-free road map indicating conditions of individual shops along these streets was designed for use by wheel-chaired visitors. It is suggested to make wider use of such maps with the cooperation of local shops and volunteers.

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Since the Wellbeing Life-care service station with the Ubiquitous Computing Network (UCN) allows for wellbeing and healthcare systems to be used in the patients' living space environments, it is crucial to develop a life-care system that is equipped with both synchronous vital data transmission and interactive multimodal user interface. This study proposes the development of a Wellbeing Life-care service system with interactive multimodal interface system that uses smart objects, such as wellbeing life-care space ¹and smart-table², in the ubiquitous computing life. The major functions of this service system are the unrestricted vital data acquisition and its manipulation, as well as an interactive multimodal interface acquired by smart-table including the interactive visual, acoustic, smell and touch modality functions for the related user interface technologies. The smart station is designed for the life-care required users who are not accustomed to the current smart spaced community computing environment; an usability model was designed on the convenience of operating the services. Furthermore, a supporting service application was developed to the Point of Care System³ and was installed in this healthcare service system to provide the patient's health information to the doctor directly. This system assists in ubiquitously providing the users' health information to the medical agents or institutes as well as communicating with community users who are involved with Ubiquitous technology and UCN environments.

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This study was designed to quantitatively evaluate the level of decline of muscle strength of elderly people who are over 70's. For the experiment, twenty elderly males and females who do regular exercise (mainly walking) and another twenty elderly males and females who do not exercise were recruited. Ten young males and females at their 20's were also recruited as control group subjects. The isometric maximum strengths of shoulder, wrist, hip, knee and ankle joint were measured by using Cybex machine. ANOVA and Duncan analysis were used to examine the statistical difference among groups. In results, significant differences among groups were found at the shoulder flexion and extension, the wrist supination, the hip flexion and extension, the knee flexion and extension. Moreover, the decline rate of the maximum strength was compared between exercising elderly and the non-exercising elderly group. In conclusion, this study quantitatively showed the level of decline of muscle strength on individual joints due to either ageing or the lack of exercise. Such data can be applied to design an ergonomic working environment for elderly people. Moreover, this data can be used for trainer to design an exercise program to compensate the lack of those physical abilities.

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The proportion of people aged 60 and over to entire population is forecasted to exceed 30% in developed countries by the year 2050. Accessibility is being studied extensively since it is crucially important that the elderly access to the resources of modern economical and social life. A web application was developed in the study to examine the applicability of fundamental motor behavior laws to the elder users. Fitts' law has been believed a reliable and robust model in various human-computer interactions such as scrolling, selection of menu item, editing of documents, etc. However, movement times of the aged persons were not explained properly by Fitts' law. Target size and experience significantly affected the movement time, while distance to the target did not significantly affect the movement time. We also found that target size, age, and experience would affluence the error. Hick's law is another important principle applied to the choice response and it was inapplicable to the elderly. Target size and age except for the number of targets significantly affect choice selection time. We suggested efficient size of control objects (20-40 pixels) for senior users to minimize the performance time and error.

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Basic human body measurements (BHBMS), maximum voluntary contraction (MVC), manual strength (MS), range of motion (ROM), joint passive resistance (JPR), and physical strength (PS) were measured in a healthy Japanese population (approximately 1000 subjects, 20-84 years old) in 2001-2002, and the data of these have already been released on the NITE web page (http://www.tech.nite.go.jp/human/) as the “Human characteristics database”. BHBMS were measured at 18 measure sites. MVC, ROM, and JPR were measured in regard to the limb joints (hand, elbow, shoulder, ankle, knee and hip). MS mean the force required to push a door open, pull a door shut, turn a door knob, and all what could the subject use either arm or hand. PS was included measurement of grip strength, sitting trunk flexion, vertical jump height, jumping reaction time, and single- leg-standing time with eyes closed. The database has search and statistical analysis function, which makes it possible to retrieve data by searching for any factor and statistics (e. g., mean, standard deviation, scatterplot).

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The purpose of the study is to extract typical body shapes of Koreans based on their three-dimensional anthropometric data measured through 5^th national anthropometric survey known as SizeKorea and to examine the suitability of the 3D human shape data for vehicle interior packaging. 36 three-dimensional anthropometric variables that are related to the interior design of vehicles were considered for the generation of typical body shapes. Major factors were extracted by the factor analysis and factor scores were calculated for all subjects with respect to age groups and gender. Typical or standard drivers of Korean, who must be tested for the suitability of design during the design process, were selected by the minimum deviation criteria for the major factor scores with respect to 5^th, 50^th, and 95^th percentiles, respectively. Since human models such as HUMAN are frequently used in vehicle design, it is of great importance to make sure that its dimensions conform to those of real Korean drivers. There exist critical differences between selected anthropometric data of Korean and modeling data provided by HUMAN. This suggests that comparative research about these differences need to be undertaken and any modeling data provided by computer human models should not be applied to the ergonomic evaluation for the vehicle design without a careful review. It is also expected that anthropometric data of a set of typical drivers extracted from the study help designers conduct package layouts and improve the suitability of ergonomic evaluation for Korean customers.

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The reactor protection system (RPS) in nuclear power plants plays the roles of generating the reactor trip signal and the engineered safety features (ESF) actuation signal when the monitored plant processes reach the predefined limits. The cabinet of the RPS is used for the RPS integrity testing and monitoring by maintenance operators and is equipped with a flat panel display (FPD) with a touch screen capability as a main user interface for the RPS operation. This paper describes the human factors activities involved in the development process of the RPS: conceptual design, design guidance, and evaluation.

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For the purpose of evaluating color vision characteristic to the elderly, we made an experiment to measure calibrated brightness of a stimulus light circle comparing to white reference light circle on LCD display, corresponding to both the normal state and the cataract goggle-equipped state. In this experiment, the HSV color model was adopted because HSV model is dominant in the field of computer graphics.
From the result of the experiment, when equipped with cataract experiencing goggles, reduction of the visibility is observed for all HSV hues. And, the gap of HSV brightness between the normal and the goggles equipped state is maximum at B (blue: 240 degree), minimum at Y (yellow: 60 degree).
To characterize the experimental results, we define the sensitivity as a reciprocal of the gap. By representing sensitivities for 12 HSV hues using HSV polar coordination, it becomes clear that the sensitivity is relatively high at the right half region: from R (red: 0 degree) to C (cyan: 180 degree).

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The evaluation of the information requirement and the workload is a part of Periodic Safety Review (PSR) for Nuclear Power Plants (NPPs). The information requirement means detail elements of the essential information during performing some tasks. And also, the workload can be defined as the amount of work per hours during the operation of those tasks.
The purpose of this study is to estimate the correlation among the basic factors for working conditions, which include the information requirement and the workload, and to offer basic information of working environments. The basic factors include the frequency of task, the importance of task, number of working person, the time consumption for working, the working environment, the assistant of tool, and the requirement level of training to perform the task. The basic factors of working conditions were composed by technical references. We used 179 tasks (in 3 sites) which were selected from the officially managed procedures and related to the safety and representation of each division.

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According to the growth of the system integrity and the technical enhancement in industries, human errors have become afford to get more attentions in the aspect of the technological liability as well as the safety, performance and efficiency. There are too various methods and approaches to the human error studies to catch out the most effective one from them in one industrial field. Many trials without more careful technical criteria could be out of the ultimate target of human error studies in spite of their sincere devotions for the causal investigation and the fairly long struggling processes for the recurrence prevention. I will propose a set of new considerations for the industrial establishment of a more effective approach to the human errors in practice.

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The objective of this study is to investigate the perceived discomfort for the external load added postures which are combined with shoulder flexion/extension and elbow flexion. 12 healthy male undergraduate and graduate students participated in this experiment. Independent variables were the shoulder flexion/extension angle (-20°, 0, 45°, 90°, 135°), the elbow flexion angle (0, 45°, 120°), and the external load (0, 1.5Kg, 3Kg). Dependent variable was a whole body perceived discomfort using Borg's CR10. The subjects rated the perceived discomfort after they had maintained the given posture for 60 seconds. The ANOVA results showed that main factors and three two-way interactions were statistically significant at α=0.05. The regression analyses were performed to quantify the effect of external loads on the perceived discomfort. The perceived discomfort linearly increased as the external loads increased. The effect of the external loads to the perceived discomfort was quantified and classified into three levels based on the result of regression analyses.

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When music performers purchase the musical instrument, the good quality of the timbre is the standard of first rank and the following standard is the easiness to perform. This paper shows a scientific method to inspect whether truth or superstition for “mythical common sense” of Stradivarius called “Exquisite Instrument” using listening tests and the sound analysis of Stradivarius.

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This study aims to develop a model of ride comfort for high speed rail launched out in Korea (KTX: The Korea Train eXpress). To evaluate and to quantify the impacts and scores of each qualitative factor on the overall ride comfort, Structural Equation Model (SEM) was used. In order to construct a comprehensive ride comfort model, both the qualitative and quantitative factors were included. The influences of qualitative factors of passengers such as fatigue and medical symptoms were considered in addition to the factor of the interior, seat, and tunneling effect. Analysis results showed that the SEM model had a high level of fitness (GFI=0.928), to assure statistically acceptable reliability and validity. Among the candidate factors from conceptual model, the seat, fatigue, interior related factors showed significant effects to ride comfort of KTX. The ride comfort was most affected by the seat factors (including forward and backward seat) which could drastically increase ride comfort of passengers among all others. The results could be useful for the improvement of ride comfort in next generation KTX.

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When choosing, the girl children value externals more than the material and functions. However, we have no color image investigation of the girl children. Then, we investigated girl children's color image structure was clarified. The result both of value and chroma got high score on high tone. Moreover, it has been understood that yellow and blue receive the high appraisal in hue. Then, we propose that it is preferable that the keynote of the color used for the commodity intended for the girl children is a color with high value (especially, yellow, green hue).

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