• Journal of Biosystems Engineering
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• v.28 no.4
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• pp.305-314
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• 2003

The ROPS of an agricultural tractor is designed to protect its driver when the tractor overturns. Although the current OECD tests to determine whether the ROPS meets the requirements of the OECD regulation are desirable, they need long time to test. We experimental time and effort by using CAE. We conducted a finite element analysis for the ROPS design of a Dae-Dong tractor cabin in an attempt to reduce the design and manufacturing time. This study shows the interpretative skill using MARC(v.2000) for designing ROPS and difference between the results of testing and FEA. Design process is generally divided into two phases: a concept and a detail design. The concept design uses simple analysis to predict structural behavior, whereas the detail design involves a finite element analysis performed by the results of the concept design. This study focused on the detail design and used Patran(v.2000r2) and MARC(v.2000) of the MSC software corporation. The model consisted of 4812 elements and 4582 nodes. Four tests. specified in the OECD standards, were performed: (1) longitudinal loading test (2) rear crushing test (3) side loading test (4), and front crushing test. Independent analyses were also performed for each test, along with a sequential analysis. When compared, the results of the independent and sequential analyses were found to be similar to the test results.

• Korean Journal of Community Nutrition
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• v.25 no.4
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• pp.267-279
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• 2020

Objectives: This study investigated the utilization and satisfaction of lunchbox by considering the dietary lifestyle of the consumer, in order to refine the purchasing behavior of adults with experience in using lunchboxes, and to provide basic data for efficient menu configuration and direction towards improvement. Methods: A total of 600 adults in Seoul and Gyeonggi-do answered a self-administered questionnaire designed to investigate general characteristics, utilization, menu preference, satisfaction, prospection, and improvement of lunchbox, according to the dietary lifestyle. Results: The study subjects were classified into 5 groups: 'taste seeking group', 'safety seeking group', 'health seeking group', 'economic seeking group' and 'convenience seeking group. Considering purchase value of the lunchbox, the 'taste seeking group' had a high utilization rate (35.1%) for prices less than 4,000 won (P < 0.05). Lunchboxes were mainly purchased at the lunchbox store (43.3%) and convenience store (37.7%). The important factor that contributed to purchasing a lunchbox was taste (61.3%), which was highest in the 'taste seeking group' (P < 0.01). The 'health seeking group' showed the highest preference for the low-salt diet lunchbox menu (26.0%) (P < 0.05). The satisfaction of 'health seeking groups' was lowest when considering addition of condiments (2.34%), origin of ingredient (2.59%), and provided calorie (2.81%) (P < 0.05). The overall response indicated future use of the lunchbox (69.6%) (P < 0.01); 35.8% respondents recommended the purchase of lunchbox, where convenience of purchase was the highest factor contributing to recommendation (50.2%) (P < 0.05). Conclusions: Taken together, our results indicate that taste was emphasized in every group purchasing the lunch box. Convenience of purchase was the highest factor contributing to satisfaction, which was relatively low when considering addition of condiments, nutrition and origin of ingredients. We propose that it is necessary to improve the development of various menus for increasing satisfaction by selecting the right ingredients contributing to good health of the consumer.

• Journal of the Korean Society of Clothing and Textiles
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• v.5 no.2
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• pp.41-48
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• 1981

The purpose of this study is to examine the responses of males and females to the woman's clothing behaviors and its relationship with their family values. This paper deals with four items such as aesthetics, modesty, fashion, extravagance in clothing behavior, and six items for family values such as influence of family and family government, woman's spheres of activity, economic responsibility, relationships with relatives, organizational activity, and care of the aged. The guestionnaires were given to 470 adult males and females in Seoul-Kyunggi area. Date were analyzed statistically by correlation, t-test. The results were as follows : 1. The females scored significantly higher on the four aspects of woman's clothing behaviors the aesthetics, the modesty, the fashion, the extravagance than did the males. It was found that the females were much interested in woman's clothing behaviors than werethe males. 2. But there were no differences between males and females in order of scoring on the woman's clothing behaviors. 3. The responses of males and females to the woman's clothing behaviors were significantly related to their family values. i) Both the males and females respondents who had greater traditionalism in family values put greater emphasis to the modesty among the woman's clothing behaviors, ii) The males respondents who had great traditionalism in family values put great emphasis to the extravagance among the woman's clothing behaviors, while the females who had great traditionalism in family values put great emphasis to the aesthetics.

• The Journal of Engineering Geology
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• v.22 no.2
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• pp.157-171
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• 2012

The slope design of an open-pit mine must ensure slope stability and economic feasibility. The overall slope angle of the pit is therefore the main factor of concern because of limited support or reinforcement options available in such a setting. This study examines the optimal measurement system for monitoring the behavior of the slope in an open-pit mine using displacement measurement, data analysis, and numerical simulations for a coal mine at Pasir, Indonesia. The area of slope to be managed is extensive and the maximum displacement, as calculated by numerical analysis, is about 3,000 mm. The displacement data, measured by inclinometer and GPS, were analyzed, and the applicability of SSR (slope stability radar) was reviewed in comparison with other monitoring systems.

• Health Policy and Management
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• v.30 no.1
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• pp.100-111
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• 2020

Background: Few studies have examined the performance of the public long-term care insurance (LTCI) from the perspective of geographic equity. This study investigated regional variations and associated factors in the supply and utilization of nursing home care within and also between Japan and Korea. Methods: A comparative dataset was developed by extracting data from 2013-2015 LTCI statistics yearbooks and Organization for Economic Cooperation and Development regional statistics, as well as other comparable data in Japan and Korea. The unit of analysis was the prefecture in Japan and the province in Korea. We computed variation indices and conducted regression analyses for regional variations within each country and decomposition analyses to examine the variations between the countries. Results: The overall regional supply and use of nursing home care were higher in Japan, but the regional variations in Korea were larger than in Japan. In both countries, the nursing home supply was negatively associated with the proportion of older people with independent living. Nursing home use was also negatively associated with the supply of hospital beds and home care agencies in Korea; the relationship was the opposite in Japan, however. The country-based differences were more likely to be explained by differences in the distributions of the variables included in the analytical model than country-specific characteristics. Conclusion: Regional-level nursing home supply and use were unequal in both countries, and the contributing factors were not the same. Policy efforts are needed to advance regional equality in long-term care (LTC) and collaboration between health and LTC institutions for frail older people, especially in Korea.

• Journal of the Society of Disaster Information
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• v.13 no.2
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• pp.249-257
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• 2017

Recently, a cable disconnection accident occurred due to a lightning strike at the Seohae Bridge located in Dangjin-Pyeongtaek City. This is a natural occurrence, but it is a recall that it is very important to review the safety issues due to the disconnection of cable bridges. In other words, the role of cables in cable bridges has a profound effect on the safety of the structure, and it has become necessary to grasp the effect on the entire structural system. The cable bridge is an economic bridge that builds the main tower and supports the bottom plate by cable. The influence of the cable is the main member, which is a big influence on the safety of the whole bridge system. In the cable-stayed bridge, the cables exhibit nonlinear behavior because of the change in sag, due to the dead weight of the cable, which occurs with changing tension in the cable resulting from the movement of the end points of the cable as the bridge is loaded. Modal analysis is conducted using the deformed dead-load tangent stiffness matrix. A new concept was presented by using divided a cable into several elements in order to study the effect of the cable vibration (both in-plane and swinging) on the overall bridge dynamics. The result of this study demonstrates the importance of cable vibration on the overall bridge dynamics.

• The Korean Journal of Health Service Management
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• v.8 no.2
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• pp.197-208
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• 2014

This study examined the relationship between social support and depressive symptom among the middle and old-aged people, using dataset of the Korean Longitudinal Study of Ageing(KLoSA 3rd). The subjects were 7,874 persons aged 45 and over. Using this data, social support variables and its relation to depressions was observed based on social network model. A multiple regression model was used to study an association between social support and depressive symptom, controlling for socio-economic characteristics, health status and behavior. Also, this paper run two subgroup regression models based on gender of subjects (male, female), controlling for confounding variables. Authors found that there was lower the number of meetings with friends (1~3 times in a week: b=0.597, p<0.0001; 1~2 times in a month: b=0.609, p<0.0001; 1~6 times in a year or under: b=1.598, p<0.0001) and negative relationship between spouse satisfaction (b=-0.007, p=0.0237), children satisfaction (b=-0.019, p<0.0001) and depressive symptom. Also quantitative effect differences were compared according to gender and its effect on depression. Compared to the male group, female group showed significant difference in quantitative effect with number of meetings with friends and spouse satisfaction, but children satisfaction didn't show clear differences according to gender. This study suggested the importance of social support for promoting mental health among the middle and old-aged people.

• Steel and Composite Structures
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• v.35 no.4
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• pp.599-609
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• 2020

The tension-only braced frames (TOBFs) are widely used as a lateral force resisting system (LFRS) in low-rise steel buildings due to their simplicity and economic advantage. However, the system has poor seismic energy dissipation capacity and pinched hysteresis behavior caused by early buckling of slender bracing members. The main concern in utilizing the TOBF system is the determination of appropriate performance factors for seismic design. A formalized approach to quantify the seismic performance factor (SPF) based on determining an acceptable margin of safety against collapse is introduced by FEMA P695. The methodology is applied in this paper to assess the SPFs of the TOBF systems. For this purpose, a trial value of the R factor was first employed to design and model a set of TOBF archetype structures. Afterwards, the level of safety against collapse provided by the assumed R factor was investigated by using the non-linear analysis procedure of FEMA P695 comprising incremental dynamic analysis (IDA) under a set of prescribed ground motions. It was found that the R factor of 3.0 is appropriate for safe design of TOBFs. Also, the system overstrength factor (Ω₀) was estimated as 2.0 by performing non-linear static analyses.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.2
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• pp.19-28
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• 1999

While the codifying works or the earthquake resistant design codes for buildings and bridges have been carried out progressively, such works for tank structures are still at the beginning steps. In case of the collapse of tank structures under seismic actions, substantially severe damages are expected due to the spillage of tank contents in addition to the direct economic losses of tanks and contents. Therefore not only the analysis and verification methods for the dynamic behavior of tank structures but also the measures of minimizing the damage propagation should be included in the codes for tank structures. In this paper the design concepts and principles, the analysis and verification methods as well as the measures against the damage propagation are set forth, which are mandatory for the preparation of the earthquake resistant design codes for cylindrical liquid-storage steel tanks.

• Structural Engineering and Mechanics
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• v.37 no.6
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• pp.671-684
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• 2011

Deciding on an optimal sensor placement (OSP) is a common problem encountered in many engineering applications and is also a critical issue in the construction and implementation of an effective structural health monitoring (SHM) system. The present study focuses with techniques for selecting optimal sensor locations in a sensor network designed to monitor the health condition of Dalian World Trade Building which is the tallest in the northeast of China. Since the number of degree-of-freedom (DOF) of the building structure is too large, multi-modes should be selected to describe the dynamic behavior of a structural system with sufficient accuracy to allow its health state to be determined effectively. However, it's difficult to accurately distinguish the translational and rotational modes for the flexible structures with closely spaced modes by the modal participation mass ratios. In this paper, a new method of the OSP that computing the mode shape matrix in the weak axis of structure by the simplified multi-DOF system was presented based on the equivalent rigidity parameter identification method. The initial sensor assignment was obtained by the QR-factorization of the structural mode shape matrix. Taking the maximum off-diagonal element of the modal assurance criterion (MAC) matrix as a target function, one more sensor was added each time until the maximum off-diagonal element of the MAC reaches the threshold. Considering the economic factors, the final plan of sensor placement was determined. The numerical example demonstrated the feasibility and effectiveness of the proposed scheme.