• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.2
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• pp.247-264
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• 2023

Objectives: The study was to examine the features of three-dimensional(3D) face dimensions and to develop fit test panels for the labor population using respirators in South Korea. Methods: This study was part of the first-year work of a two-year-project conducted at Occupational Safety and Health Research Institute in 2021. After 3D head dimensions data were collected from Size Korea Center managing Sixth Size Korea databases, 3D face dimensions DB for the South Korean labor population was established for 21 items of face dimensions in line with the ISO/TS 16976-2 and KS A ISO 15535. With the South Korean labor population 3D face dimensions DB, in accordance with the ISO/TS 16976-2, the descriptive statistics of 3D face dimensions were calculated and two fit test panels were developed. Results: A total of 2,752 subjects were finally determined and they were 52.9% for male, 41.2% for the highest age-group of 15-29, and residents in the capital area. Mean and standard deviation were obtained for each of the 21 3D face dimensions items for the South Korean labor population. Among the items, male and female face widths were 137.6±5.7 mm, 133.2±5.0 mm, respectively. Male and female face lengths were 116.6±7.0 mm, 107.8±6.8 mm, respectively. Two new South Korean fit test panels, a bivariate test panel and a principal component analysis test panel, were developed using the 3D face dimensions DB as well. Conclusions: Using the 3D face dimensions DB, the mean and standard deviation were featured for each of the 21 items and also the two fit test panels were newly developed in the study. It is suggested that the study outputs should be utilized practically and effectively in selection, use, and management of respirators at work, expecting that respiratory protection can be furthermore improved for respirator users including labor population across the country.

• IE interfaces
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• v.15 no.2
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• pp.199-208
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• 2002

This study was performed to measure the various dimensions of the head and face for Korean adults. Three hundred and eighteen males and two hundred and sixty females, age ranged 18 to 60, participated for this study. Thirty-six dimensions were selected to measure. Subjects were divided into three age groups - 18 to 29, 30 to 39, and 40 to 60 - for each sex. The data were analyzed ta see the differences between the age groups and sex using SAS program. Also, the results of this study were compared to the data of Japanese and US. army. The results showed that the 'ear length', 'bigonial breadth' and 'bitragion submandibular arc' increased as the age increased(p<0.01). However, not much of differences were shown between the age groups in most of other dimensions. Males were significantly bigger than females in every dimensions. The comparison between Korea and Japanese showed significant differences in many dimensions. Due to this reason, it is considered that more caution has to be exercised in using Japanese data for the Korean. The Americans showed to be significantly bigger than Korean in most dimensions. It showed that Koreans have more roundish face and wider nose ridge than Americans. The results of this study can be used to design the products that related to the head and face.

• Journal of Korean Society for Quality Management
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• v.50 no.3
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• pp.545-570
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• 2022

Purpose: The purpose of this study was to explore dimensions to improve airline non-face-to-face(untact) service quality and identify shadow work dimensions in the digital environment among them. Methods: This study conducted mixed method. First of all, For finding out the dimensions of airline untact service quality, in-depth interviews were conducted from passengers. The collected data through the survey were analyzed using improved importance-performance analysis(IPA). Second, An online survey was conducted to quantitatively analyze user perception about airline untact service quality, and the importance performance of service quality at each dimension was identified through the revised IPA method. Results: The results of this study are as follows; Through in-depth interviews, 11 dimensions found out and 32 measurement items were developed. and then, through the revised IPA analysis, passengers were highly satisfied with "Cleanliness of in-flight service" and "Reliability of self check-in". Also, We found 3 shadow work dimensions such as "Ease of use of self check-in", "Usefulness of self check-in", and "Responsiveness of self check-in". Conclusion: Airline service providers have to keep high-satisfaction services and urgently improve less satisfied services. In particular, the dimensions related to shadow work have to be improved.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.34 no.3
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• pp.279-291
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• 2024

Objective: This was to develop headforms for the labor population, based on a three-dimensional(3D) face dimensions data base(DB) and a principal component analysis(PCA) fit test panel, in selection, use and maintenance of respirators in Korea. Methods: This study was part of a two-year-project initiated in 2021. The study was designed and conducted in line with ISO 16976-2 while subjects were those employed in the development of the PCA fit test panel. The approaches included literature review; examination on conformity of the 3D face dimensions DB; and development of headforms representing the labor population. The mean data were used in order to construct each model of the headforms through a way of 3D modeling and 3D printing technology. Results: A total of 2,752 subjects were determined. Five models of headforms(small, medium, large, long-narrow, short-wide) were completely constructed for the labor population. For example, means of the 10 face dimensions for medium headform model were: minimum frontal breadth 106 mm, face width 136 mm, jaw width 127 mm, face length 111 mm, interpupillary distance 69 mm, head breadth 164 mm, nose protrusion 12 mm, nose breadth 34 mm, nasal root breadth 35 mm, and nose length 50 mm. Conclusions: Five models of headforms were newly constructed using the study data. It is likely desirable that the constructed headforms, together with the 3D face dimensions DB as well as the PCA fit test panel, can be utilized more effectively in selection, use and maintenance of respirators for users including the labor population.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.32 no.2
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• pp.124-134
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• 2024

This study is based on the Expectation Confirmation Theory (ECT) and categorizes trust types in non-face-to-face boarding services into three dimensions: structural assurance, platform, and service provider. It analyzes the impact of these trust types on users' perceived usefulness, satisfaction, and continuous usage intentions. Using a structural equation model, the study found that the three dimensions of trust positively influence users' satisfaction and perception of usefulness, thereby promoting intentions for continuous use. However, perceived risk weakens the positive relationship between trust and continuous usage intentions. By exploring the moderating role of perceived risk in non-face-to-face boarding services, this study analyzes its impact on user behavior patterns, contributing to the optimization of service design and enhancement of user trust. This study promotes widespread acceptance and continuous use of the service, and is crucial for developing effective non-contact service strategies that meet the needs and expectations of Chinese travelers in the post-pandemic travel environment. The findings provide a new perspective and empirical evidence for understanding user attitudes and behaviors towards non-face-to-face services, holding significant theoretical and practical implications.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.6
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• pp.1163-1177
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• 2020

The purpose of this study is to figure out the information needed to improve the shape and size suitability of face-applied mask sheets. The study analyzed the shape of the mask sheet from the scanned images of 50 products of 37 domestic brands. In addition, each measurement of 42 mask sheets were compared and analyzed multilaterally with the 3D measurement dimensions of the faces of men and women in their 20s from the 6th SizeKorea data. Analysis on the shapes of mask sheets indicated that domestic commercial mask sheets are mainly made of single or dual sheets, with slits for enhancing fitness to the three-dimensional face. In the dimensional analysis of Korean men, women and mask sheets, most of the lengths of the mask sheets were significantly larger or smaller than the actual faces of men and women. The horizontal length and vertical length of the forehead above the eyes are significantly shorter, thereby requiring adjustments in the dimensions of this area. In order to improve the size suitability of the mask, it is necessary to adjust the dimensions of the problem area according to the research results as well as diversify the dimensions considering the target layer.

• International Journal of Contents
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• v.3 no.2
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• pp.1-5
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• 2007

This paper proposes a technique for principal component analysis (PCA) to raise the recognition rate of a front face in a low dimension by hierarchical image and parallel processing structure. The conventional PCA shows a recognition rate of less than 50% in a low dimension (dimensions 1 to 6) when used for facial recognition. In this paper, a face is formed as images of 3 fixed-size levels: the 1st being a region around the nose, the 2nd level a region including the eyes, nose, and mouth, and the 3rd level image is the whole face. PCA of the 3-level images is treated by parallel processing structure, and finally their similarities are combined for high recognition rate in a low dimension. The proposed method under went experimental feasibility study with ORL face database for evaluation of the face recognition function. The experimental demonstration has been done by PCA and the proposed method according to each level. The proposed method showed high recognition of over 50% from dimensions 1 to 6.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.703-708
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• 2009

The present paper describes the application of an improved impression transfer vector method (Sakurai et al., 2007) to transform the three basic dimensions (Evaluation, Activity, and Potency) of higher-order impression. First, a set of shapes and surface textures of faces was represented by multi-dimensional vectors. Second, the variation among faces was coded in reduced parameters derived by applying principal component analysis. Third, a facial attribute along a given impression dimension was analyzed to select discriminative parameters from among principal components with higher sensitivity to impressions, and obtain an impression transfer vector. Finally, the parametric coordinates were changed by adding or subtracting the impression transfer vector and the image was manipulated so that its facial appearance clearly exhibits the transformed impression. A psychological rating experiment confirmed that the impression transfer vector modulated three dimensions of higher-order impression. We discussed the versatility of the impression transfer vector method.

• The korean journal of orthodontics
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• v.24 no.2
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• pp.405-417
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• 1994

The purpose of this study was to investigate proportional characteristics of soft tissue profile in Korean young adults. The sample consisted of 50 young adults(25 males and 25 females) who had pleasing profile and normal occlusion. Soft tissue proportional analysis was performed on lateral cephalograms taken in natural head position. The results were as follows : 1. Mean and standard deviation of proportional analysis were obtained. 2. Horizontal and vertical dimensions were larger in male. But facial proportion had no sexual difference except upper/lower face height (p<0.05). Upper/lower face height was larger in female than in male. 3. Vertical dimensions, except SN-ST, had high correlation with horizontal dimensions. 4. Head positioning error of natural head position was smaller than inter -individual variability of SN line.

• Journal of Preventive Medicine and Public Health
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• v.50 no.6
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• pp.361-368
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• 2017

Objectives: This study aimed to explore dimensions in addition to the 5 dimensions of the 5-level EQ-5D version (EQ-5D-5L) that could satisfactorily explain variation in health-related quality of life (HRQoL) in the general population of South Korea. Methods: Domains related to HRQoL were searched through a review of existing HRQoL instruments. Among the 28 potential dimensions, the 5 dimensions of the EQ-5D-5L and 7 additional dimensions (vision, hearing, communication, cognitive function, social relationships, vitality, and sleep) were included. A representative sample of 600 subjects was selected for the survey, which was administered through face-to-face interviews. Subjects were asked to report problems in 12 health dimensions at 5 levels, as well as their self-rated health status using the EuroQol visual analogue scale (EQ-VAS) and a 5-point Likert scale. Among subjects who reported no problems for any of the parameters in the EQ-5D-5L, we analyzed the frequencies of problems in the additional dimensions. A linear regression model with the EQ-VAS as the dependent variable was performed to identify additional significant dimensions. Results: Among respondents who reported full health on the EQ-5D-5L (n=365), 32% reported a problem for at least 1 additional dimension, and 14% reported worse than moderate self-rated health. Regression analysis revealed a $R^2$ of 0.228 for the original EQ-5D-5L dimensions, 0.200 for the new dimensions, and 0.263 for the 12 dimensions together. Among the added dimensions, vitality and sleep were significantly associated with EQ-VAS scores. Conclusions: This study identified significant dimensions for assessing self-rated health among members of the general public, in addition to the 5 dimensions of the EQ-5D-5L. These dimensions could be considered for inclusion in a new preference-based instrument or for developing a country-specific HRQoL instrument.