• Journal of the Ergonomics Society of Korea
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• v.26 no.4
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• pp.91-101
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• 2007

The purpose of this study is to propose an optimal layout for the accelerator and brake pedals in sedan and SUV, and also to compare the pendant-type pedal with organ-type pedal. 12 male subjects participated in the experiment, the subjects were divided into 3 groups according to height percentile(under 50%ile, 50%ile to 75%ile, over 75%ile). Independent variables were seat height (H₃₀), X and Y coordinates of the center of accelerator and brake pedals and the x and y relative distance between two pedals. Dependent variable was subjective ratings for lower body discomfort. The response surface methodology using a central composite design was employed to develop a prediction model for lower body discomfort of each pedal. It is noticeable that the lateral position of the accelerator in all groups was not statistically significant. The optimal locations of both pedals were found to be distinct according to the percentile of subjects. X distance from accelerator to brake of both-type pedals is similar. But Y distance from accelerator to brake of organ-type is less about 2-3cm than that of pedant-type.

• Journal of the Ergonomics Society of Korea
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• v.26 no.4
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• pp.57-64
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• 2007

In the world, the old population is growing fast and many countries went into an advanced age society. Therefore the development of everyday products, electric appliances, and welfare services considering old people is more important than ever. In particular, the complexity of products can cause many problems for old people. Universal design is an approach to create environments and products that recognizes the diversity of users, regardless of their ability or age. Universality evaluation for a product is very important to verify old people's accessibility and usability for the product. Universality means how good a product was designed in view of universal design principles. In this study, UNIX, a method to evaluate the universality of a product was developed. UNIX was based on seven universal design principles; equitable use, flexibility in use, simple and intuitive, perceptible information, tolerance for error, low physical effort, size and space for approach and use. UNIX is a kind of expert evaluation and very simple method. The method is consisted of two steps. In the first step, relative weights for seven principles and subjective ratings on design suitability for each principle are obtained. In the second step, universality index (UNIX) of each product is obtained by weighted average multiplying relative weights and rating scores. As a case study, this method was applied for mouse designs. In conclusion, this method could be effectively applied to evaluate the universality of a product.

• Korean Journal of Clinical Pharmacy
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• v.15 no.2
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• pp.94-99
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• 2005

The aim of this study was to evaluate the safety and efficacy of treatment of mesoglycan. This study was conducted between September 2003 and May 2004. A total of 292 patients with vascular disorders including cerebral infarction were enrolled. The patients were administered with 50-100mg of mesoglycan by an oral route everyday for eight weeks. Subjective physicians' assessments of efficacy had ratings of 'improvement', 'invariability', 'exacerbation' and 'not being able to assess'. An improvement was observed in 241 patients out of 274; 18 patients were rules out. The efficacy rate was influenced statistically significantly by the duration of therapy (p=0.0392) and daily mean drug dose (p<0.0001). The adverse events were reported in 8 patients (9 cases) out of 292 patients: skin/appendages disorders (0.7%), liver/biliary system disorders (0.7%), cardiovascular system disorders (0.7%), neurologic disorders (0.3%). respiratory disorders (0.3%) and gastrointestinal system disorders (0.3%). There showed no serious adverse events. These results indicate that mesoglycan was well tolerated and effective for the prevention of vascular disorders.

• Journal of the Korean Society of Safety
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• v.30 no.6
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• pp.132-138
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• 2015

This study examined the relative effects of feedback frequency and specificity of Eco-IVIS(eco in-vehicle information system) on the fuel-efficiency and workload. Eighty participants randomly assigned into four experimental groups (high frequency/specific, high frequency/global, low frequency/specific, and low frequency/global feedback) and they drove 16.4Km motorway under the each feedback condition. The dependent variable were fuel efficiency and Drive Activity Load Index which measured participants' subjective ratings of driving workload. The results showed that high frequent feedback was more effective for increasing fuel-efficiency than low frequent feedback, however, there was no significant difference of fuel-efficiency between specific and global feedback. Although, overall DALI score was comparable among four experimental conditions, visual demand score was significant higher under the high frequent feedback condition than low frequent feedback.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.9
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• pp.1567-1580
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• 2010

This study investigates the effects of visual texture on color emotion and establishes prediction models for color emotion by both physical color properties and visual texture characteristics. A variety of fabrics including silk, cotton, and flax were colored by digital textile printing according to chromatic hue and tone combinations that are evaluated in terms of color emotion. Subjective visual texture ratings are also obtained for gray-colored same fabrics to those used in color emotion tests. As a result, fabric clusters by visual texture factors showed significant differences in color emotion factors that are primarily affected by physical color properties. Finally prediction models for color emotion factors by both physical color properties and visual texture clusters were established, which has a potential to be used to explain color emotion according to the visual texture characteristics of fabrics.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.04a
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• pp.281-284
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• 2008

The purposes of this study were to make clear the present condition of indoor thermal environment in apartment units and to analyze the relation of the living factors with indoor thermal elements. The field surveys consisted of measurements on physical elements and observations on living factors and interview on resident's subjective responses were carried out in 20 apartment units. The field surveys were carried out during the $January{\sim}March$ 2007. Measuring elements were air temperature, globe temperature, and relative humidity. As results, the averages of indoor temperature each houses were $21.2{\sim}27.2^{\circ}C$, the number of houses exceed the comfort zone were 4. The averages of globe temperature each houses were $21.3{\sim}27.5^{\circ}C$, 6 houses exceeded the comfort zone. The means of relative humidity were $19.5{\sim}58.8%$, relatively dry condition. The clothing value of residents were $0.39{\sim}0.89$ clo(average 0.68 clo). The average of thermal sensation ratings each room were $4.2{\sim}4.8$, 'neutral'$\sim$'slightly warm'. The results of regression analysis on relations of living factors with the thermal elements are as follow; ventilation time(outdoor air exchange), door opening time with balcony, and gas cooker use time had significant effect on indoor temperature.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.2
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• pp.326-332
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• 1996

In this paper, a method to design the sending loudness rating(SLR) is proposed and the desirable transmission characteristics are considered in order to specify the transmission quality, based on the loudness ratings, for the digital telephone system that is a terminal for digital speech communication. To specify the desirable SLR for digital telephone system, the subjective test defining the preferred range of inout level for CODEC was performed. From the test results, it was identified that the optimal input level for CODEC is -15dB and the range not to cause the quantization noise and the distortion of CODEC fall within -12dB and -18dB.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.25-33
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• 2014

This study has intended to build a rural landscape evaluation model based on an integrated landscape assessment paradigm of rural region using an additive integration index method and applied the model to the Seondong Region of Gochang-gun, Jeollabuk-do, Korea. To reach this goal, this study developed a model to calculate Integrated Landscape Assessment Index. The model has employed the Objective Landscape Index, the Subjective Landscape Index, and the weighted values, and was applied to the Seondong region. This study has found the following results: 1) forests and water spaces were assessed with relatively better visual preferences and better landscape ecosystem; 2) the historic cultural area and scenic agriculture as well as general farm land were assessed with moderate ratings; and, 3) the villages included in development plan, their adjacent arable farming land, and the village watercourses were forming relatively poorer landscape.

• Nuclear Engineering and Technology
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• v.52 no.5
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• pp.984-994
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• 2020

It is reported that about 20% of accidents at nuclear power plants in Korea and abroad are caused by human error. One of the main factors contributing to human error is fatigue, so it is necessary to prevent human errors that may occur when the task is performed in an improper state by grasping the status of the operator in advance. In this study, we propose a method of evaluating operator's fitness-for-duty (FFD) using various parameters including eye movement data, subjective fatigue ratings, and operator's performance. Parameters for evaluating FFD were selected through a literature survey. We performed experiments that test subjects who felt various levels of fatigue monitor information of indicators and diagnose a system malfunction. In order to find meaningful characteristics in measured data consisting of various parameters, hierarchical clustering analysis, an unsupervised machine-learning technique, is used. The characteristics of each cluster were analyzed; fitness-for-duty of each cluster was evaluated. The appropriateness of the number of clusters obtained through clustering analysis was evaluated using both the Elbow and Silhouette methods. Finally, it was statistically shown that the suggested methodology for evaluating FFD does not generate additional fatigue in subjects. Relevance to industry: The methodology for evaluating an operator's fitness for duty in advance is proposed, and it can prevent human errors that might be caused by inappropriate condition in nuclear industries.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.7
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• pp.2399-2413
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• 2021

A recommendation system is an information filter tool, which uses the ratings and reviews of users to generate a personalized recommendation service for users. However, the cold-start problem of users and items is still a major research hotspot on service recommendations. To address this challenge, this paper proposes a high-efficient hybrid recommendation system based on Fuzzy C-Means (FCM) clustering and supervised learning models. The proposed recommendation method includes two aspects: on the one hand, FCM clustering technique has been applied to the item-based collaborative filtering framework to solve the cold start problem; on the other hand, the content information is integrated into the collaborative filtering. The algorithm constructs the user and item membership degree feature vector, and adopts the data representation form of the scoring matrix to the supervised learning algorithm, as well as by combining the subjective membership degree feature vector and the objective membership degree feature vector in a linear combination, the prediction accuracy is significantly improved on the public datasets with different sparsity. The efficiency of the proposed system is illustrated by conducting several experiments on MovieLens dataset.