• 대한관절경학회지
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• 제6권1호
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• pp.37-42
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• 2002

목적 : 관절경적 반월상 연골 봉합술시 인대 손상 동반 여부에 따른 결과를 분석하였다. 대상 및 방법 : 20례를 대상으로 하였으며 평균 추시 기간은 59.7개월이었다. 환자의 연령은 평균 32.3세였다. 동반 인대 손상이 없는 경우와 동반 손상인대를 치료한 17례를 안정 관절군으로, 동반 손상을 치료하지 않은 3례를 불안정 관절군으로 비교하였다. 안정 관절군은 급성기와 만성기로 분류하였다. 결과는 Lysholm 및 IKDC 평가법으로 판정하였다. 정상 및 아정상군은 만족으로, 비정상 및 장애군은 불만족으로 구분하였다. 통계적인 방법은 Wilcoxon rank sum test, fisher's exact test(p<0.05)를 이용하였다. 결과 : 동반 손상인대를 동시에 치료한 8례는 만족 $87.5\%$, Lysholm score는 평균 90.9을 보였고, 동반 손상을 치료하지 않은 3례는 만족 $66.7\%$, Lysholm score는 평균 77.7을 보였다 동반 인대 손상이 없는 9례는 만족 $88.9\%$, Lysholm score는 평균 91.4을 보였다. 급성기에 치료한 12례는 만족 $91.7\%$, Lysholm score는 평균 92.5를 보인 반면, 만성기의 5례는 만족 $80\%$, Lysholm score는 평균 88.6을 보였다. 결론 : 수상 후 급성기에 파열된 반월상 연골 및 동반 손상인대의 관절경적 복원술을 동시에 시행하는 것이 좋은 결과를 얻을 수 있을 것으로 사료된다.

• 한국실내디자인학회논문집
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• 제14권5호
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• pp.218-225
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• 2005

In this apartment market, many apartments are being reconstructed within even less than 20 years from their first construction. This entails many problems in environmental and economical facets, for which many researches are under way in several institutions and universities. International cases show that the international trend goes for remodeling of maintenance, management, and repairing rather than new building. The purpose of this study is to investigate the factors of cost evaluation for establishing the time period of apartment based on durability of material and equipment while considering the economic feasibility of apartment, when remodeling as a concept of sustainability regarding building is being vitalized. This study investigates the proper period of remodeling in consideration of weight accruing to the LC(Life Cycle) and cost based on the standardized durability. The weight of cost, period establishment analysis, and LC according durability varies the data values of remodeling periods. The physical durability and cost from this data enable the investigation into not only the repair period of individual materials of the apartment but also remodeling period.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.446-459
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• 2000

This study was carried out in order to find out an effective machinery utilization strategy by conducting a survey on utilization and maintenance of agricultural machinery. The survey showed that the no. of utilization hours for power tiller in a year was 190.2hrs, 208.6hrs for tractor, 59.1hrs for rice transplanter, 74.0 hrs for combine, 44.6 cultivator and 254.4hrs for 4.4hrs for grain dryer. The period covered the time the machine was until it became unserviceable. The results are as follows: 10.0yrs for power tiller, 7.5yrs for tractor, 7.4yrs for rice transplanter and 5.4yrs for combine. This indicate that the actual period of use for power tiller and rice transplanter was longer than the expected period of duration years so there is a need for adjustment. The factors considered by the farmers for purchasing agricultural machine were: farm size(32%), machine operation (26.0%), performance(l4.0%) and post or after sales service(12.6%), according to the survey. It showed that repair cost rate in a year was classified into major agricultural machine; 4.8% for combine; 3.9% for tractor; 3.5% for rice transplanter; 2.0% for power tiller; 1.6% for grain dryer; and 1.2% for cultivator. The reasons for poor maintenance were insufficient after sales service(25%) and difficulty in buying parts(75%) because of the unavailability of parts in local shops(55%), imported models(30%) and outmoded model(15%).

• Journal of Ginseng Research
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• 제28권1호
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• pp.18-26
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• 2004

The effect of Panax ginseng administration in muscle inflammatory process induced after eccentric exercise, that causes myofibrillar disruption, was studied. Changes in lipid peroxidation, inflammation, glycogen levels in muscle and release of myocellular proteins to blood were measured. The analyses were performed immediately after eccentric exercise and over week since this period are necessary for the muscle damage-repair cycle. The ginseng extract (100 mg kg$^{-1}$ ) was orally administered to rats for three months, before the eccentric exercise performance. The results showed the protective role of ginseng against skeletal muscle damage. This effect could be associated with their membrane stabilising capacity since creatine kinase (CK) activity was significantly decreased 96 h post-exercise from 523$\pm$70 to 381$\pm$53 and 120 h post-exercise from 443$\pm$85 to 327$\pm$75 in treated animals. $\beta$-glucuronidase activity, as indicator of inflammation, showed a significant reduction of about 15-25% in soleus, vastus and triceps in these post-exercise times. The lipid peroxidation, measured by malondyaldehyde levels, was significantly decreased in the 24 h post-exercise period in soleus and vastus intermedius muscles and on the recovery period. Finally ginseng administration reduced significantly the decrease of the glycogen levels immediately after exercise and when the regenerative process took place (72-168 h post exercise). Collectively, the results have showed that ginseng did not inhibit the vital inflammatory response process associated with the muscle damage-repair cycle but presumably ameliorate the injury.

• 건축역사연구
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• 제20권1호
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• pp.61-75
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• 2011

This study aims to investigate the changing aspects about research methodology of stone pagoda from the period of Japanese colonial to now. There were the differences in purpose, method and analysis of the research according to each period. In Japanese colonial period, the purpose of research was to make lists of almost stone pagodas in Korea. Following this, Japanese researchers conducted detailed research for academic purpose. They took measurements of stone pagodas and made drawings. After liberation the research was focused on the relics contained in pagodas. They proceeded to investigate the inner relics in order to attract the attention of the people. In the late 1900's, the repair works of cultural heritages were increased. Many reports of the repair works were released and sent to administration offices. The reports contained the change aspects of situation between before work and after with drawings or simple investigation documents. In the 1990's, the restoration works for important stone pagodas were started by the National Research Institute of Cultural Heritage. Since then, researches from various way - architectural and conservational researches about historical interpretation, shape, structure, proportion, technique, etc. - progressed for careful restoration and accurate study. In Recent years, various professional organizations(in the field of structure, physics, chemistry, biology, lithology, etc.) started to join the researches. Researches conducted studies directly with the stone pagodas, as well as conducting indirect studies with the stone pagodas, such as the structural stability of stone pagodas, the characteristics of rock, and conservation chemicals. Today the research project 'The preservation project of stone cultural property' is being conducted by the National Research Institute of Cultural Heritage. The purpose of this project is to gain more detailed and accurate investigation documents to be provided for the people. In conclusion, researches from various fields must be included in the research. Furthermore, a synthetic study should be done through comparing similar characteristics or different characteristics among many research results.

• 산업경영시스템학회지
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• 제41권2호
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• pp.24-31
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• 2018

As a system complexity increases and technology innovation progresses rapidly, leasing the equipment is considered as an important issue in many engineering areas. In practice, many engineering fields lease the equipment because it is an economical way to lease the equipment rather than to own the equipment. In addition, as the maintenance actions for the equipment are costly and need a specialist, the lessor is responsible for the maintenance actions in most leased contract. Hence, the lessor should establish the optimal maintenance strategy to minimize the maintenance cost. This paper proposes two periodic preventive maintenance policies for the leased equipment. The preventive maintenance action of policy 1 is performed with a periodic interval, in which their intervals are the same until the end of lease period. The other policy is to determine the periodic preventive maintenance interval minimizing total maintenance cost during the lease period. In addition, this paper presents two decision-making models to determine the preventive maintenance strategy for leased equipment based on the lessor's preference between the maintenance cost and the reliability at the end of lease period. The structural properties of the proposed decision-making model are investigated and algorithms to search the optimal maintenance policy that are satisfied by the lessor are provided. A numerical example is provided to illustrate the proposed model. The results show that a maintenance policy minimizing the maintenance cost is selected as a reasonable decision as the lease term becomes shorter. Moreover, the frequent preventive maintenance actions are performed when the minimal repair cost is higher than the preventive maintenance cost, resulting in higher maintenance cost.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 2002년도 학술대회지
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• pp.159-175
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• 2002

The effect of Panax ginseng administration in muscle inflammatory process induced after eccentric exercise, that causes myofibrillar disruption, was studied. Changes in lipid peroxidation, inflammation, glycogen levels in muscle and release of myocellular proteins to blood were measured. The analyses were performed immediately after eccentric exercise and over week since this period are necessary for the muscle damage-repair cycle. The ginseng extract $(100\;mg\;kg^{-1})$ was orally administered to rats for three months, before the eccentric exercise performance. The results showed the protective role of ginseng against skeletal muscle damage. This effect could be associated with their membrane stabilising capacity since creatine kinase (CK) activity was significantly decreased 96 h post-exercise from $523{\pm}70\;to\;381{\pm}53$ and 120 h post-exercise from $443{\pm}85\;to\;327{\pm}75$ in treated animals. ${\beta}-glucuronidase$ activity, as indicator of inflammation, showed a significant reduction of about $15-25\%$ in soleus, vastus and triceps in these post-exercise times. The lipid peroxidation, measured by malondyaldehyde levels, was significantly decreased in the 24 h postexercise period in soleus and vastus intermedius muscles and on the recovery period. Finally ginseng administration reduced significantly the decrease of the glycogen levels immediately after exercise and when the regenerative process took place (72-168 h post exercise). Collectively, the results have showed that ginseng did not inhibit the vital inflammatory response process associated with the muscle damage-repair cycle but presumably ameliorate the injury.

• 한국자동차공학회논문집
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• 제18권1호
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• pp.31-36
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• 2010

Collecting all failures during life cycle of vehicle is not easy way because its life cycle is normally over 10 years. Warranty period can help gathering failures data because most customers try to repair its failures during warranty period even though small failures. This warranty data, which means failures during warranty period, can be a good resource to predict initial reliability and permanence reliability. However uncertainty regarding reliability prediction remains because this data is censored. University of Wuppertal and major auto supplier developed the reliability prognosis model considering censored data and this model introduce to predict reliability estimate further "failure candidate". This paper predicts reliability of telecommunications system in vehicle using the model and describes data structure for reliability prediction.

• Communications for Statistical Applications and Methods
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• 제9권1호
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• pp.21-31
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• 2002

This paper considers a Bayesian approach to determine an optimal replacement policy for a repairable system with warranty period. The mathematical formula of the expected cost rate per unit time is obtained for two cases : RFRW(renewing free-replacement warranty) and RPRW(renewing pro-rata warranty). When the failure time is Weibull distribution with uncertain parameters, a Bayesian approach is established to formally express and update the uncertain parameters for determining an optimal replacement policy. Some numerical examples are presented for illustrative purpose.

• 응용통계연구
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• 제15권1호
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• pp.107-117
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• 2002

본 논문에서는 혼합보증기간이 있는 수리 가능한 시스템에 대하여 보증기간이 종료된 이후의 교체정책을 고려한다. 이러한 교체정책은 보증기간이 재생되는 재생혼합보증과 재생되지 않는 비재생혼합보증에 대하여 고려되며, 최적의 교체정책을 설정하기 위 해서 단위 시간당 기대비용을 사용한다. 재생혼합보증과 비재생혼합보증이 있는 시스템에 대하여 소비자 관점에서의 단위 시간당 기대비용을 구하고, 이를 최소화하는 최적의 보전기간을 결정한다 그리고, 시스템의 고장시간이 와이블분포일 때 수치적 예를 통해서 제안된 최적의 교체정책을 설명한다.