• 한국신뢰성학회지:신뢰성응용연구
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• 제17권3호
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• pp.246-255
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• 2017

Purpose: This study proposes the optimal PM (preventive maintenance) policy of leased equipment for lessee's decision-making using two types of reliability condition. Methods: We consider reliability threshold based PM model. Equipment reliability is estimated and used as condition variable. The effect of repair for maintenance is imperfect and represented by age reduction factor. Results: We provide two PM policies. Policy 1 is focused on minimized total cost. This policy guarantees reliability threshold until last maintenance action. Policy 2 focus on maintaining reliability threshold during leased period. The proposed approach provides optimal reliability threshold under number of PM. Through result, we finally construct decision-making process for lessee using reliability threshold and end of reliability. Conclusion: This study provides two PM policy for lessee's decision-making. Through numerical example, we get a result of optimal reliability threshold, number of PM, optimum alternative under lessee's reliability condition.

• 한국의류학회지
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• 제45권2호
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• pp.253-270
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• 2021

This survey provides research into developing knee braces to protect the knee against damage, reduce knee pain, and strengthen the knee. A total of 235 surveys were conducted from December 2019 to January 2020. The subjects were adults in their 20s and over who lived in the Seoul metropolitan area and had experience of using knee braces. In terms of age differences, subjects over 60 years of age purchased knee braces mostly to secure a reduction of pain (ROP), whereas subjects in their 20s and 30s purchased knee braces for physical shock protection (PSP). Subjects in their 40s and 50s purchased knee braces for improvement of muscle movement (IMM). There was no significant difference in shape, material, and locking method based on the reason for wearing the knee brace. These results show that it is conceivable and maybe preferable to produce different knee braces-with a variety of shapes, materials, and locking materials-according to the reason behind wearing a knee brace. Knee braces are worn currently without any differentiation despite the findings of this study. In particular, we argue the need for functional and differentiated development of knee braces specifically for PSP, ROP, and IMM.

• 한국의류학회지
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• 제47권1호
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• pp.110-122
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• 2023

The COVID-19 pandemic increased people's time at home and caused an 80% increase in noise disputes between floors. The purpose of this study is to propose suitable materials for making indoor shoes (insoles) to minimize noise between floors. Subjects without back pain and leg-related disease (e.g. arthritis, etc.) from three different age groups (childhood, adolescence, and adulthood) were recruited for the study. Five polymer insole materials were considered: Chloroprene Rubber (CR foam), Ethylene Propylene Diene Monomer (EPDM foam), Natural Latex foam, Ethylene Vinyl Acetate (EVA foam), and Polyurethane (PU foam). From these materials, 20 combinations were prepared and randomly tested for noise and vibration. The results revealed a significant difference in noise and vibration levels based on the type of material used and the age of the subject. Nevertheless, all materials under consideration successfully reduced noise and vibration; in particular, type A-C greatly decreased. The CR foam material was especially effective at noise and vibration reduction (p<.01). This study suggests that adding insoles into socks that children wear at home could reduce noise vibration and disputes between floors.

• 한국유기농업학회지
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• 제31권4호
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• pp.327-341
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• 2023

The Ministry of Agriculture, Food and Rural Affairs, Hanwoo Association and Nonghyup have discussed proactive reduction measures for cows in response to concerns about an oversupply of hanwoo to ensure supply stability. This study aims to empirically analyze whether the cow fattening support program is being implemented in line with its objectives. Based on the analysis of beef traceability data, the slaughter age of participating cows was reduced by 7.6 to 14.7 months compared to non-participating cows. And heifer was reduced 1.5 months in their slaughter age. In case of parity, participating cows showed a reduction of 1.4 compared to non-participating cows. Through the SUR model, an analysis was conducted to examine the effect of the cow fattening support program on the suppression of calf production numbers. The analysis results showed that the calf production numbers are positively influenced by the number of fertile cow and the quantity of semen sales. Furthermore, it is estimated that calf production decreased as the fat index increased, and during the period when the cow fattening support program was implemented, an average monthly suppression of 3,558 calves was observed.

• 대한디지털의료영상학회논문지
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• 제14권1호
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• pp.13-20
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• 2012

In a normal x-ray examination, the cooperation of a patient in positioning greatly influences the improvement of work performance, the quality of the images and the reduction in time spent on the examination. An attempt was made to discover the connection between an examination information printout and the effects of the examination by informing the patient before the examination on the examination positions in order to increase the level of cooperation by the patient and by surveying the degree of satisfaction of the patient during the examination proceedings. An examination information printout was prepared on five positions that patients consider to be difficult while receiving normal x-ray examinations and were shown to 257 male and female patients between the ages of 30 to 79 who had visited this hospital between January 1 to February 29, 2012 or to a person who had accompanied the patients before the examination to research the degree of satisfaction regarding the printout. In addition, the examination explanation printout was given to Radiologic Technologists with over 1 year experience in this hospital to use while taking the x-rays and the degree of satisfaction was surveyed and it was examined if the increase of the degree of satisfaction had an effect on the reduction in the examination time. The patients who utilized the examination information printout revealed results of approximately a 7.8% higher degree of satisfaction among the patients who had previous experience receiving x-ray examinations compared to those were having an x-ray for the first time. In the age groups between 30 to 70 years of age, the age group in the 30's revealed the lowest level of satisfaction at approximately 69% and the group in the 50's showed the highest degree of satisfaction of 87.94%. In the survey of the Radiologic Technologists, 85% responded that they were satisfied. In the question that stated "Will the examination information printouts reduce the time involved in unnecessary conversations with the patients?," the responses showed a 95% degree of satisfaction. The degree of satisfaction was high over the examination information printout by both the patients and the Radiologic Technologists. Although the effects of examination time reduction varied based on the ages of the patients and physical conditions that they were in and could not be given measurement values, it was able to be seen through the survey that reduction of the unnecessary communication between the patient and the Radiologic Technologists contributed to the increase in the degree of satisfaction. As a result, both the patients and the Radiologic Technologists had an increased degree of satisfaction over the examination information printout and it was possible for improvements to be made in the quality of medical service provided as well. Nevertheless, it is considered that a more developed manual in terms of quality and quantity must be produced using a more systematic approach and design.

• 대한간호학회지
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• 제2권1호
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• pp.237-246
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• 1971

The purpose of this study is to observe the effects of ice-pack application on different body areas and to note which body area produces the best results according to age, room temperature, sex and disease. Seventeen patients, including six men and eleven women, hospitalized at Seoul National University Hospital from May 22 to August 29, 1971, ranging in age from 15 through 60 years with an oral temperature of 38℃ or over, were chosen for this study. They were observed with regard to the effect of the ice-packs after applications for 30, 45 or 60 minutes. Four ice-packs, 7.6inch by 9 inch, were applied on the chest and the abdominal surface in the control group and the same size and number of packs on the axillae and political regions in the experimental group. The study results were reviewed in a statistical method to obtain the following findings 1. There was no significant difference in the change of the body temperature between the control group and the experimental group after applying the packs for 30, 45 or 60 minutes. 2. Individually, there was a significant difference in the change of body temperature between before and after application for 30, 45 or 60 minutes. 3. The difference of room temperature also had no merle influence on the body temperature taken immediately before applying the ice-packs. Even when ice-packs were applied for 30, 45 or 60 minutes, the room temperature did not influence the reduction of temperature in the patient. 4. There was a significant difference in the change of the body temperature, according to the sex, after application for 30, 45 or 60 minutes. Male patient's body temperature decreased far more noticeably than the female patients and the degree of reduction became more pronounced the longer the packs were applied. 5. In regard to age, in adults, the degree of reduction in the body temperature by the application of ice-packs was similar after appling them for 30, 45 or 60 minutes and did not depend upon the length of application. 6. Regardless of the disease, there was no great difference in the reduction of body temperature when the ice-packs were applied for 30 or 45 minutes, except for patients with typhoid fever when a striking decrease in the fever resulted after a 60 minute application of the ice-pack.

• 한국환경보건학회지
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• 제34권2호
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• pp.124-130
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• 2008

This study investigated the age dependencies in ambient air pollution-associated asthma hospitalization from 2003 to 2005 in Seoul. For all ages and the age groups of 0-14, 15-64, and 65+years, the Generalized Additive Model (GAM) was used to estimate the relative risks of daily asthma hospitalization associated with changes in particulate matter and ozone. The time-trends, seasonal variances, day effects, temperature, humidity, and pressure at sea level were controlled in the models. Significant associations were observed between asthma hospitalization and the levels of $PM_{10}$ and $O_3$. The relative risks (RRs) of asthma hospitalization for every 10 unit increases in $PM_{10}({\mu}g/m^3)$ and $O_3$(ppb) were 1.008 (95% CI 1.005-1.012), and 1.012 (95% CI 1.003-1.020), respectively. Evaluated over $10\;{\mu}g/m^3$ increase in $PM_{10}$, we found the relative risks of asthma hospitalization to be 1.009 (95% CI 1.004-1.014) in 0-14 age group, and 1.015 (95% CI 1.008-1.022) in 65+ age group. Considering 10 ppb increase in $O_3$, those were 1.014 (95% CI 1.003-1.024) in 0-14 age group, and 1.025 (95% CI 1.009-1.041) in 65+ age group. It was concluded that current levels of ambient air pollution in Seoul make a significant contribution to the variation in daily asthma hospitalization. Further reduction in air pollution is necessary to protect the health of the community, especially that of the higher risky groups including children and elderly population.

• 한국심리학회지 : 문화 및 사회문제
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• 제17권4호
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• pp.365-380
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• 2011

본 연구는 연령대를 확대한 경우에도 서두름 행동의 구조가 안정적으로 유지되는지 확인하고, 성과 연령에 따른 서두름 행동의 특성을 파악하기 위해 진행되었다. 이를 위해 602명의 성인이 서두름 행동 질문지에 응답하였으며, 불성실한 응답자를 제외한 591명의 자료를 분석하였다. 요인분석 결과, 서두름 행동은 5개 요인으로 이루어져 있었으며, 이것은 다시 2구조를 재구성하는 것으로 나타났다. 즉, 연령을 확대해도 서두름 행동의 구성요인과 구조는 유지되는 것으로 나타났다. 한편, 남녀의 서두름 행동을 비교한 결과, 전반적으로 여성의 서두름 행동 수준이 남성의 서두름 행동 수준보다 높은 것으로 나타났다. 끝으로 서두름 행동은 연령이 증가함에 따라 감소하는 것으로 나타났다. 논의를 통해 남녀의 서두름 행동 차이의 의미를 해석하였으며, 연령이 증가할수록 서두름 행동 수준이 낮아지는 것을 연령이 증가함에 따라 나타나는 속도저하가 신체적 기능뿐만 아니라 심리적 기제와도 관련되어 있음을 보여주는 단서로 제시하였다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제44권2호
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• pp.73-78
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• 2018

Objectives: The goal of this study was to evaluate the rates of complications, morbidity, and safety with the transparotid approach. Materials and Methods: A retrospective study was conducted and consisted of 53 surgically treated patients in the past five years for low condylar neck and subcondylar fractures. Only patients with malocclusion and who underwent open reduction with internal fixation with the retromandibular transparotid approach were included. The examined parameters were postoperative suboptimal occlusion, deflection, saliva fistula, and facial nerve weakness. Results: Fifty-three patients had an open reduction with internal fixation on 55 sides (41 males, 77.4%; mean age, 42 years [range, 18-72 years]). Four patients (7.5%) experienced transient facial nerve weakness of the marginal mandibular branch, but none was permanent. Four patients had a salivary fistula, and 5 patients showed postoperative malocclusion, where one needed repeat surgery after one year. One patient showed long-term deflection. No other complications were observed. Conclusion: The retromandibular transparotid approach is a safe procedure for open reduction and internal fixation of low condylar neck and subcondylar fractures, and it has minimal complications.

• 동아시아식생활학회지
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• 제6권3호
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• pp.381-391
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• 1996

The main purpose of this study is to investigate the effect of housewives' dietary awareness and habits on the reduction and recycling of food waste products. We have done statistical analyses of 501 questionnaires answered by housewives living in Taegu city. The results are as follows: The dietary awareness is significantly different according to the housewives' ages. The group of above 50's age and the group of housewives and their husbands with a lower education level have a more traditional awareness and eating up habits. Also the younger group, and those with a higher education level who grew up in a big city have a more progressive dietary awareness. But the younger, higher income, small family, higher education level groups, and also employed housewives, produced more food waste products than the other groups, The groups thsose have traditional or rational awareness concerning dietary awareness, and those with good eating up and accurate cooking habits turned out to have more affirmative effects on the reduction and recycling of food waste products.