• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.12
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• pp.1322-1328
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• 2009

This paper presents vibration analysis of maskless exposure module in printed circuit board(PCB) manufacturing system. In order to complete exposure process in PCB, masking type module has been widely used in electronics industries. However, masking process confronts some limitations of application due to higher production cost for masking as well as lower printing resolution. Therefore, maskless exposure module is started to be in the spotlight for flexible production system to meet the needs of fabrication in variable patterns at low cost. Since maskless exposure process adopts direct patterning to PCB, vibration problems become more critical compared to conventional masking type process. Moreover, movements of exposure engine as well as stage generate vibration sources in the system. Thus, it is imperative to analyze the vibration characteristics for the maskless exposure module to improve the quality and accuracy of PCB. In this study, vibration analysis using the finite element analysis is conducted to identify the critical structural parts deteriorating vibration performance. Also, Experimental investigations are conducted by single/dual encoder measurement process under the operating module speed. Measurement points of vibration are selected by three places, which are base of stage, exposure engine and top of stage, to check the effect of vibration from the exposure engine. Comparisons between analysis results and experimental measurement are conducted to confirm the accuracy of analysis results including the developed FE model. Finally, this studies show feasibility of optimal design using the developed FE analysis model.

• Advances in aircraft and spacecraft science
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• v.7 no.6
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• pp.553-570
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• 2020

To address the problems caused by the strong coupling of an airbreathing hypersonic vehicle's airframe and propulsion to the integrated control system design, an integrated airframe-propulsion model is established, and the coupling characteristics between the aircraft and engine are analyzed. First, the airframe-propulsion integration model is established based on the typical nonlinear longitudinal dynamical model of an air-breathing hypersonic vehicle and the one-dimensional dual-mode scramjet model. Thrust, moment, angle of attack, altitude, and velocity are used as transfer variables between the aircraft model and the engine model. The one-dimensional scramjet model can accurately reflect the working state of the engine and provide data to support the coupling analysis. Second, owing to the static instability of the aircraft model, the linear quadratic regulator (LQR) controller of the aircraft is designed to ensure attitude stability and height tracking. Finally, the coupling relationship between the aircraft and the engine is revealed through simulation examples. The interaction between vehicle attitude and engine working condition is analyzed, and the influence of vehicle attitude on engine safety is considered. When the engine is in a critical working state, the attitude change of the aircraft will not affect the engine safety without considering coupling, whereas when coupling is considered, the attitude change of the aircraft may cause the engine unstart, which demonstrates the significance of considering coupling characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.107-116
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• 1984

In order to obtain an information for the improvement of wives' meal management especially in dual-income families, the survey was carried out through questionaires to 159 married women teachers(employed wives: EW) and 157 housewives(HW) in Daejeon city, from the Sep. 20 to 30, 1983. Most of the two groups' wives did not plan menu(74.7 %), and considered taste firstly when meal preparation and food buying. In EW, time was more considered than the other points for meal preparation and cookbook was more used than other sources of cooking methods, while in HW, cost, and, the mass media (p<0.01). Among 6 convenience foods, sausage, ham were used more frequently in EW and instant noo-dles and fried fish cake, in EW. Both the two groups' dietary pattern of three meals was similar, but much more of the EW(56.1 %) purchased foods for between meals rather than prepared at home in comparision with the HW. Almost all the HW prepared three meals themselves but the EW did not so. In the EW, husband and mother-in-law often assisted with meal-related activities, but in the HE, daughters (p<0.01) . HE spent more time on meal-related activities than do EW (Hw: 4.1 hrs/day, Ew·: 3.2 hrs/day) . The preparation time for supper was longest among three meals. As the problems of meal management, both the two groups' wives pointed 'too much time' (43.1 %), 'lack of nutrition knowledge '(42.8 %), but EW' husbands, 'no variety of cooking method'(42.8 %), while HW' husbands, 'lack of nutrition knowledge'(34.3 %).

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.4
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• pp.229-237
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• 2013

As demand for IT services increase, which are based on SOA and cloud computing, service level agreements (SLAs) have received more attention in the parties concerned. An SLA is usually a paper contract written in natural language. SLA management tools which are commercially available, implement SLAs implicitly in the application with a procedural language. This makes automation of SLA management difficult. It is also laborious to maintain contract management systems because changes in a contract give rise to extensive modifications in the source code. We see the source of the trouble is the existence of documentary SLAs (paper contracts) and corresponding executable SLAs (contracts coded in the procedural language). In this paper, to resolve the current SLA management problems we propose an active SLM (Active Service Level Management) system, which is based on the active SLA (Active Service Level Agreement). In the proposed system, the separated management and processing of dual SLAs can be unified into a single process with the introduction of active SLAs (ASLAs).

• Journal of Korean Medicine Rehabilitation
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• v.19 no.4
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• pp.135-150
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• 2009

Objectives : Osteoporosis is the most common metabolic disease of the bone, and one of the most important public health problems around the world. Obesity rate gradually increases as women grow older. The purpose of the study was to investigate the changes between bond mineral density(BMD) and body mass index(BMI) according to sex and age. Methods : We measured the bone mineral density(BMD) of lumber spine(L2-L4) and femoral neck in 10000 normal adult, using dual energy X-ray absorptiometry (DEXA; DPX-alpha). and also measured the body mass index(BMI) in 9810 normal adult. then we analysed the changes of BMD and BMI according to sex and age. Results : 1. As getting older, male's T-score of lumbar spine(L2-L4) was slowly decreased. On the other hand, female's T-score of lumbar spine was sharply dropped after 46 years old. 2. As getting older, male's T-score of femoral was slowly decreased. On the other hand, female's T-score of femoral was sharply dropped after 49 years old. 3. Irrespective of age, male's BMI keep up the extent within a definite period of numerical value. As getting older, female's BMI continued its upward trend. Conclusions : Much more attention should be needed for female patient suffering from osteoporosis and obesity than male.

• Korean Journal of Social Welfare
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• v.44
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• pp.146-177
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• 2001

One of the difficulties of female-headed families face is economic hardship. Low-income single mothers work long hours, become isolated and feel burdened for dual roles. And many of them don't have relatives to share parenting roles. As a result, children of low-income female-headed families are easy to be neglected and left to form a delinquency-prone group in neighborhood. Traditionally, it has been viewed that children in female-headed families have problems due to the loss of father role. However, study indicates that these children can adjust well if the relationship between mothers and children is consistent and adequate. An Intervention program for low-income female-headed elementary children was developed and delivered in two community social welfare centers. The purpose of the program is to raise self-esteem. Two goals were 1) management of daily living habits and 2) improvement of family relations. Social workers maintained contact with mothers to talk about children's behaviors and to prompt hugging and touching. In addition, workers helped children to form good relationships with peers and school teachers. Children were satisfied with the program. Their family relations were improved statistically significantly after the program(wilcoxon signed rant test z=-2.934 p<.05). However, their self esteem were not improved significantly (wilcoxon signed test z=-1.173 p>.05). Qualitative analysis of each children were also discussed. The implications of the study are the followings: Intervention programs need to be delivered separately for low-grade and high grade elementary children because they have different developmental needs. The program also need to include education on sex and marriage as well as aggression reduction. Society needs to provide more support to single mothers for their personal and parenting needs.

• The Journal of Korean Academic Society of Nursing Education
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• v.10 no.1
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• pp.84-93
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• 2004

Purpose: This study was conducted to investigate the subjective degree of fatigue, the degree of fatigue depending on constitution, and the factors related to fatigue in middle-aged women. Method: Data were collected from 51 patients, registered at Oriental Medicine Hospital in J-city and K-city respectively. The instrument used in this study were the Multidimensional Assessment of Fatigue and the Questionnaire of Sasang Constitution Classification Ⅱ. Data analysis was done SPSS Result: The characteristics of constitution in middle-aged women could be divided into three: twenty six people of Soeumin, thirteen people of Taeumin, and twelve people of Soyangin. The degree of fatigue in middle-aged women: the average score 30.61 out of the total score 40. Subdivision of fatigue scores: common fatigue degree 7.71, distress due to fatigue 7.67, degree of daily activity fatigue 7.43, and fatigue frequency in the previous week 7.84. There were significant differences in the degree of fatigue depending on constitution in middle-aged women(p=.033). This study revealed weight, exercise, and drinking are important factors that can exert influence on the degree of fatigue. Also, there was a big difference in the degree of fatigue depending on constitution. Conclusion: In conclusion, fatigue is one of the difficult problems with middle-aged women. And this study revealed that change in the weight(especially loss of weight), physical exercise, and drinking are important factors that can exert influence on the degree of fatigue. Also, there was a big difference in the degree of fatigue depending on constitution. Therefore it is necessary to develop Korean nursing intervention to providing an appropriate environment where there is the harmony of the dual principles of the negative and positive, and patients can be taken care of properly.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.5925-5932
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• 2014

The aim of this study was to develop assessment tools for analyzing society focusing on abilities, not an academic clique. The development of a type of occupational qualification, which is called a working and learning system, for Koreans, can be reliable and acceptable to a variety of society members. This study was conducted by searching for a dual system and examining a qualification system in developed countries. To achieve the goal of this study, the management status according to a type of qualification system was analyzed. In addition, a variety of related laws, related department, testing authority, testing institute, terms of applying for tests, way of testing, committee of testing, testing subjects, criterion for passing tests, a status of qualification test administrated in some developed countries, such as Germany, UK, the USA and Australia, were conducted. The occupational duty of the machine field and education contents are examined by analyzing the occupational duty. In addition, the criterion to solve problems and a way of marking in the field of machines were indicated and an example of written and practical tests is presented. This study makes a blueprint for a qualification system of working and learning at the same time in a national dimension.

• Journal of The Korea Institute of Healthcare Architecture
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• v.23 no.1
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• pp.15-24
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• 2017

Purpose: Korea is expected to enter an aged society in 2018 and then a super-aged society in early 2025. The country's aging is progressing faster than any other country in the world. However, the foundation of the elderly friendly industry is weak, and measures at the government level are urgently needed. Especially, housing problems of the elderly are one of the most urgent measures to be taken. Korea does not have the minimum residential area standard for the elderly, and the current general minimum residential area standard is based on the survey of the housing situation without scientific evidence. Therefore, both standards need to be revised as soon as possible based on scientific evidence. Methods: The minimum residential area standard has been calculated following Karl H. E. Kroemer's Min or Max design also being called as-single cut and dual cut theory- as the maximum population value and minimum population value theory of Ernest J. McCormick. Therefore there is a need for a formula made using a few key factors, such as corresponding dimension, practical dimension, clearance, spare dimension, integrated dimension. These elements can be defined and used as formulas to calculate minimum residential area standards. Results: Assuming the results of the spatial variability in this study showed that it is possible to raise the standard of living in a terms of sustainable minimum size for the young, old and all residents. Implications: The government should set a minimum residential area standard with scientific grounds and set up a policy improving the life of people who live in an needy residential environment.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.123-133
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• 2006

Seoul and many large cities in Korea have implemented Median Exclusive Bus Lane(MEB). But exclusive bus lane in the middle of the road caused new contradictions between left turn movement and through bus movement and several signal operation techniques like 'left turn Protected' and 'overlap phase' couldn't be applied in intersections on MEB. We suggest 'Bus-only Signal for median lane technique as solution of these problems This study presents optimum signal time design process and detailed algorithms for intersections where bus-only signals are installed. As a test field. we took Yang-Je intersection where Median Exclusive Bus Lane go through. and have large gap in volume of left turn in main direction. And we verified that revised optimum signal time including overlap phase can reduce average delay time of vehicle through before and after simulation.