• 한국가구학회지
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• 제16권2호
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• pp.59-65
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• 2005

As physical condition of students improves, there is a need to develop human body-friendly desk and chair for students. In this study, desks and chairs were manufactured with curved veneer lamination under high frequency heating and pressing, using ten wood species such as Japanese red pine, Korean pine, pitch pine, Japanese larch, yellow poplar, black locust, oak, radiata pine, beech, and birch. The performance of these products were evaluated. The results obtained were summarized as follows; With high frequency heating, the turned lamination of veneers with full size sheet ($3{\times}6\;feet$) prepared by rotary lathe peeling was successfully applied for making the members of desk top, leg frames of desk and chair. Bending strengths of desk tops were relatively greater for yellow poplar, black locust and red pine, which were similar to those of beech and birch. Bending strengths of desk legs were classified into greater species group (red pine, yellow poplar, larch) and lower species group (radiata pine, Korean pine, pitch pine). Compressive strengths of chair legs in parallel direction to the lamination were greater in black locust and larch. On the other hand, differences between outer and inner gap at the top and drawer bottom of desk top were rather larger for the laminations of birch and beech, and less for those of yellow poplar and pitch pine, showing greater stability of open drawer space. In results, yellow poplar, larch, pitch pine and red pine showed good appearance and strength properties at the curved veneer lamination. Accordingly, it was believed that these domestic woods were able to substitute for birch which was being imported for the use of veneer-laminates type furniture.

• 대한산업공학회지
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• 제35권1호
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• pp.1-14
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• 2009

The efficiency of transportation requests fulfillment can be increased through extending the problem of vehicle routing and scheduling by the possibility of subcontracting a part of the requests to external carriers. This problem extension transforms the usual vehicle routing and scheduling problems to the more general integrated operational transportation problems. In this contribution, we analyze the motivation, the chances, the realization, and the challenges of the integrated operational planning and report on experiments for extending the plain Vehicle Routing Problem to a corresponding problem combining vehicle routing and request forwarding by means of different sub-contraction types. The extended problem is formalized as a mixed integer linear programming model and solved by a commercial mathematical programming solver. The computational results show tremendous costs savings even for small problem instances by allowing subcontracting. Additionally, the performed experiments for the operational transportation planning are used for an analysis of the decision on the optimal fleet size for own vehicles and regularly hired vehicles.

• 산업경영시스템학회지
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• 제42권4호
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• pp.1-7
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• 2019

The customer of massage chair is expanding day by day from middle age to all ages. In 2018, the market size was 700 billion KRW, an increase of 30 times over 10 years. However, most related SMEs suffer from excessive competition by the market monopoly of some major companies. In this situation, in order for a related company to survive, it is necessary to steadily research and develop new products. Founded in 2009, company L produces massage chairs for health and relaxation of customers. L's products use a sound wave vibration module that is favorable for human body, unlike other products that use vibration motor type. However, frequent breakdowns of massage chair due to the vulnerability of plate (leaf) springs, which play an important role in sound wave vibration modules, made sap its competitiveness. In this paper, we propose a method to design desirable plate spring structure by sequentially experimenting with five different plate springs. The results of this study are expected to contribute to improve the quality of plate spring and the reliability of sound wave vibration module. In the future, it is necessary to find a way to use it in the development of foot massage or scalp management device as well as continuous research to find optimal plate spring structure through various analysis.

• 한국간호교육학회지
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• 제22권4호
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• pp.485-494
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• 2016

Purpose: The present research is a descriptive study aimed at understanding clinical nurses' Video display terminal (VDT) syndrome and identifying the factors that affect their VDT syndrome. Methods: Data were collected from 239 clinical nurses working in two metropolitan cities. Research tools included subject's VDT syndrome assessing musculoskeletal, ophthalmic, dermal, psychiatric, and whole body syndromes. The data were analyzed using frequency analysis, average and standard deviation, t-test, One-way ANOVA, and multiple regression analysis with the SPSS/WIN 20.0 program. Results: The subjects' VDT syndrome score was 1.34 out of 5. There were significant differences in participating subjects' VDT syndrome, hospital's size, working unit, health status, diagnosis of illness, having an Order Communication System (OCS), having an Electronic Medical Record (EMR) System, continuous VDT working for more than one hour, break time during VDT use, VDT use time, comfort of the chair, adjustability of the height of the chair, size of the VDT's desk, distance between the monitor and the user's eyes, resolution of the monitor, and frequency of eye exercise during VDT use. According to the research, influencing factors on VDT syndrome in clinical nurses included size of the VDT's desk, frequency of eye exercise during VDT use, having an EMR system, break time during VDT use, diagnosis illness, and having an OCS' system. Conclusion: The findings from this study can be used as a basis for future VDT syndrome prevention education and programs for clinical nurses.

• 한국학교보건학회지
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• 제8권2호
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• pp.219-232
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• 1995

대구지역 중 고등학교 학생들의 학교 책상과 의자의 표준 호수 사용 여부와 그에 따른 신체적 자각 증상 호소율을 조사하기 위하여 1995년 3월 20일에서 4월 19일 사이에 대구지역내에 소재한 남.여, 중 고등학교 전학년 학생 1,201명을 대상으로 설문 조사를 실시하여 분석한 결과는 다음과 같다. 중 고등학교 학생들이 사용하는 책상과 의자는 표준 호수보다 1~3호 정도 높은 것이 대부분이었으며, 희망 호수 역시 조금 높은 것을 선호하는 것으로 나타났다. 표준 호수를 사용하고 있는 학생은 책상 30.5%, 의자 21.0%였고. 표준호수보다 큰 호수를 사용하고 있는 경우는 책상 61.3%, 의자65.2% 였으며 표준 호수 보다 작은 경우는 각각 8.2%, 13.8%였다. 중학교의 표준 호수 사용율은 책상 44.1%, 의자 26.8%로 고등학교의 16.1% 및 14.7%보다 높았고, 남학생은 책상 31.5%, 의자 24.5%로 여학생의 29.6% 및 17.6%보다 높았다. 공립학교의 표준 호수 사용율은 책상 34.2%, 의자 24.5%로 사립학교의 27.1%, 및 17.5%보다 높은 편이지만 양군 모두 표준호수 사용율은 낮았다. 책상 사용시 가장 불편한 점으로는 낡았다, 서랍이 좁다, 낮다, 면이 고르지 않다의 순이었고. 의자 사용시 가장 불편한 점은 의자면이 딱딱하다, 등받이가 딱딱하다, 낡았다, 낮다, 높다, 면이 좁다의 순이었다. 책상 및 의자의 사용으로 인한 신체부위별 통증 호소율은 중학교 남.여학생에선 목 어깨 호소율이 각각 32.2%, 36.0%로 가장 높았고, 고등학교 남.여학생은 허리 호소율이 각각 37.9%, 44.1%로 가장 높았다. 신장이 증가할수록 허리 통증 호소율이 높은 것으로 나타났으며, 목 어깨 통중은 전반적으로 높게 호소했다. 책상 및 의자를 표준 호수로 사용활 경우 목 어깨 통증 호소율은 각각 25.4% 및 23.8%인데 비해 표준 호수보다 큰 책상이나 의자를 사용하는 경우는 각각 31.5% 및 31.8%로 호소율이 높았으며, 작은 경우 역시 26.5% 및 28.9%로 높았다. 표준 호수 보다 크거나 작은 책상 및 의자를 사용하는 경우에 비해 표준 호수를 사용할 경우 허리통증 호소율이 모두 낮았다. 대구지역 중 고등학교 학생들의 책상 및 의자의 표준 호수 사용율은 매우 낮았으며, 사용하는 책상과 의자 호수가 자신이 희망하는 호수와 많은 차이를 보이고 있으며, 이에 따른 신체 부위별 통증 호소율은 비교적 높게 나타났다. 따라서 학생들의 체격조건을 고려하여 책상과 의자를 구입, 배분하는데 최대한의 배려를 하여야 할 것이며, 표준호수와 선호도를 반영한 다양한 호수의 잉여책상과 의자의 보유비율을 높여야 할 것으로 생각한다.

• 한국의류학회지
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• 제17권2호
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• pp.197-206
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• 1993

We studied relation between the clothing pressure applied by foundations(waist nipper, girdle, body suit) on the waist of bodies and muscular activity, feeling of tightness. The main results were summerized as follows ; 1. Clothing pressure applied by foundations was high in order of girdle>waist nipper>body suit, also clothing pressure was higher back than front and side, sitting on the chair than standing posture, ventral flection than repose. Individual differences, even if size of body was equal, were shown in clothing pressure applied by foundations with subcutaneous fat's amount in measuring region. 2. The muscular activity of rectus abdominis than obliquus externus abdominis was more affected by foundations in all kinds of postures and motions. Amplitude of electromyogram was high sitting on the chair than standing posture, but there was little difference with motion variation. The wearing girdle strongly affected on the muscular activities of rectus abdominis and obliquus externus abdominis as compared with waist nipper and body suit. 3. The value for feeling of tightness by wearing waist nipper was higher than girdle and body suit. Also the case when sitting on the chair and ventral flection, the value for feeling of tightness was high. When the foundations were on the body, most tightened on the region of the body was anterior abdominal region.

• 한국산업보건학회지
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• 제19권1호
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• pp.16-24
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• 2009

This research aims to measure and analyze the dimensions of typical office chairs and desks sold in domestic market, and to suggest the modifications of national guidelines considering Korean peoples' body characteristics. The scope of this study was limited to the desktop type of computer jobs, excluding laptop environment. The dimensions of 24 different office chairs and 7 tables were measured, and their dimensions were analyzed against the Ministry of Labor (MOL) Notification and Korean Standards (KS). At the same time, the data from the Size Korea was also considered. As a result, the KS guidelines were overall fulfilled by the measured products, while the MOL Notification was not. It was found that the guidelines on the chair height, seat pan depth, lumber support height, and armrest height need to be modified. Some inconsistencies between the MOL Notification and KS were also found. It is suggested that the required dimensions specified by both guidelines should be unified.

• 한국가구학회지
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• 제16권1호
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• pp.81-89
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• 2005

A chair is a necessary tool in modern life and people spend a lot of time on it. But there Ere so many chairs which the human body size Is not considered that many users usually feel fatigue. The purpose of this study is to analyze the fundamental items human factors engineering which have to be applied to chairs and then to make user choose chairs, considering them as an index. The extent of this study is limited to chairs for office work used for sitting for a long time to work. We also profoundly analyze functional matters of chairs, user's posture and so on. We'll present all suitable factors and the assumed tentative plan by inferring items', the function chairs have coincides with the human body.

• International Journal of Fluid Machinery and Systems
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• 제6권4호
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• pp.177-187
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• 2013

A scaling method valid for most turbomachines based on first principles is derived. It accounts for axial and centrifugal turbomachines with respect to relative gap width/tip clearance, relative roughness, Reynolds number and/or Mach number for design and off-design operation as well. The scaling method has been successfully validated by a variety of experimental data obtained at TU Darmstadt. The physically based, hence reliable and universal method is compared with previous, empirical scaling methods.

• 한국실내디자인학회논문집
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• 제16권2호
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• pp.262-269
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• 2007

The blur phenomenon obscuring the boundary between the field of designers and that of users may be the key paradigm in the 21st century. However, we observed a number of chair design cases that could be considered as the results of blur pheonomenon in the furniture design field from mid 1960s. The backgrounds include the repulsion against the uniform functionalism, deliberation on the life in the future and the development of plastic materials and their processing methods. Under such backgrounds, the designers pursued the new and futuristic furniture design. In that process, what is about the "freedom" that the consumers as well as the designers should have in using the furniture was the important concept. This concept enabled the creation of chair design inducing the participation of consumers. They created various kinds of shapes, functions and structures that the consumers became interested in as if they had fun with toy blocks by mainly using the new material "plastic". In a formative aspect, the entire shape is classified into the organic shape and geometric shape. The unit types are divided into two kinds; type that the unit of simple shape is repeated only with size difference and irregular combination type of the units comprised of more than two shapes. In the functional aspect, some cases showed the transformation and expansion of the function more variously. Other cases changed the function of chairs to tables, cabinets, or objects. In the structural aspect, on the basis of the method assembling each unit, one method is to assemble using the hardware and the other is to assemble only with intrinsic units of chair. The chair design created by the blur phenomenon between the designers and the users as described above causes the blur phenomenon between the furniture and the space where the furniture is installed. Accordingly, it is expanding the furniture design sphere including the case that the furniture is not selected as the rifle article depending on the characteristics of interior space but it becomes the element leading the characteristics of space. This study aims to estimate the change of interior space and the furniture that my cause the blur phenomenon by examining the cases above appropriate for the paradigm of the 21st century. Furthermore, this study will enable the discussion oil the directions of future furniture design based on its results.