• 한국가스학회지
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• 제25권3호
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• pp.53-58
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• 2021

노년층뿐만 아니라 청년층에 속하는 성인들 사이에서도 병원 외 심장정지(OHCA)를 겪는 심장질환자의 수가 증가하고 있다. 자동심장충격기(AED)는 병원 외 심장정지 환자의 생존율을 개선하는 데 있어 긴요하다. 심장정지 생존율은 제세동 시간에 대하여 지수적으로 감소(decline exponentially)하는 것으로 밝혀졌으나, 자동심장충격기의 최적 배치에 있어 심장정지 생존율의 이러한 특성을 반영한 국내 연구가 미미한 상황이다. 본 연구에서는 자동심장충격기의 최적 입지를 결정하기 위하여 exponential decay coverage 함수를 갖는 최대 gradual coverage 입지 모델에 대하여 고찰하였다. exponential decay coverage 함수는 심장정지 환자의 생존율에 대한 과다추정을 완화한다. 향후 시뮬레이션을 통하여 랜덤한 행인 위치 및 이동을 반영함으로써 행인의 심정지 대응에 있어 창발적인(emergent) 특징을 식별할 수 있는 시설 입지 모델이 개발될 것으로 예측된다.

• 한국군사과학기술학회지
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• 제19권4호
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• pp.443-452
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• 2016

Current low-altitude radar system often fails to detect small unmanned aerial vehicles (UAV) because of their small radar cross section (RCS) compared with larger targets. As a potential alternative, a passive bistatic radar system has been considered. We study an optimal deployment problem for the passive bistatic radar system. We model this problem as a covering problem, and develop an integer programming model. The objective of the model is to maximize coverage of a passive bistatic radar system. Our model takes into account factors specific to a bistatic radar system, including bistatic RCS and transmitter-receiver pair coverage. Considering bistatic RCS instead of constant RCS is important because the slight difference of RCS value for small UAVs could significantly influence the detection probability. The paired radar coverage is defined by using the concept of gradual coverage and cooperative coverage to represent a realistic environment.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1603-1607
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• 2012

The effects of plating process on the surface coverage of the accelerator were investigated in terms of Cu superfilling for device metallization. When a substrate having 500 nm-wide trench patterns on it was immersed in an electrolyte containing poly (ethylene glycol) (PEG)-chloride ion ($Cl^-$)-bis(3-sulfopropyl) disulfide (SPS) additives without applying deposition potential for such a time of about 100s, voids were generated inside of the electrodeposit. In time-evolved electrochemical analyses, it was observed that the process (immersion without applying potential) in the electrolyte led to the build-up of high initial coverage of SPS-Cl on the surface, resulting in the fast saturation of the coverage. Repeated experiments suggested that the fast saturation of SPS-Cl failed in superfilling while a gradual increase in the SPS-Cl coverage through competition with initially adsorbed PEG-Cl enabled it. Consequently, superfilling was achievable only in the case of applying the plating potential as soon as the substrate is dipped in an electrolyte to prevent rapid accumulation of SPS-Cl on the surface.

• Archives of Reconstructive Microsurgery
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• 제20권1호
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• pp.68-73
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• 2011

Traditional management of comminuted tibia fractures with massive bone and soft tissue defect includes soft tissue coverage and bone grafting. However, this method requires a large flap and a substantial amount of bone graft. Acute shortening can reduce the amount of required soft tissue and bone graft. We report a case of open tibia and fibula fracture with severe bone and soft tissue defect that was successfully treated by acute shortening of the tibia with immediate fibular strut bone graft and then by gradual lengthening of the tibia at its proximal metaphysis.

• Industrial Engineering and Management Systems
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• 제13권1호
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• pp.29-42
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• 2014

Extensive research has been conducted on supplier evaluation and selection as a strategic and crucial component of supply chain management in recent years. However, few articles in the previous literature have been dedicated to the use of fuzzy inference systems as an aid in decision-making. Therefore, this essay attempts to demonstrate the application of this method in evaluating suppliers, based on a comprehensive framework of qualitative and quantitative factors besides the effect of gradual coverage distance. The purpose of this study is to investigate the applicability of the numerous measures and metrics in a multi-objective optimization problem of the supply chain network design with the aim of managing the allocation of orders by coordinating the production lines to satisfy customers' demand. This work presents a dynamic non-linear programming model that examines the important aspects of the strategic planning of the manufacturing in supply chain. The effectiveness of the configured network is illustrated using a sample, following which an exact method is used to solve this multi-objective problem and confirm the validity of the model, and finally the results will be discussed and analyzed.

• 보건행정학회지
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• 제10권1호
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• pp.57-94
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• 2000

Korea's social health insurance system was introduced in 1977, which has made a universal coverage possibly by July 1989. Korean government had pursued a single objective for the last decade to put the whole population under the coverage of medical security, and the objective was achieved within 12 years. The rapid accomplishment is primarily due to such factors as limited benefits, high copayment rate, low contributions as well as rapid economic growth. There are several sources of pressure for the implementation of social health insurance such as health professional group, labor unions, politicians, international organizations etc.. However it is important to look at the feasibility of social health insurance. Among other things, it is necessary to identify the administrative infrastructure of insurance system and to assess income for source of fund. As many developed countries, Korea began to apply health insurance to the employees of the large firms, and the expansion based on employment status. Thus the several funds system was inevitable according to the gradual expansion strategy. However many persons had criticized several funds system in respect with equity and efficiency aspects. In the short history of the Korean health insurance, whether one fund or sever or funds had been the most controversial issue. In Febrary 1999, the National Assembly passed the act of one fund system. From July 2000 separate funds will be unifed under new health insurance scheme. In this study we will analyze the policy making process on implementation, expansion and integration of health insurance system of Korea. And also analyse problems related to policy making.

• Archives of Plastic Surgery
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• 제46권3호
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• pp.255-261
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• 2019

Cross-leg flaps are a useful reconstructive option for complex lower limb defects when free flaps cannot be performed owing to vessel damage. We describe the use of the extended distally based sural artery flap in a cross-leg fashion for lower extremity coverage in three patients. To maximise the viability of these extended flaps, a delay was performed by raising them in a bipedicled fashion before gradual division of the tip over 5 to 7 days for cross-leg transfer. Rigid coupling of the lower limbs with external fixators was critical in preventing flap avulsion and to promote neovascular takeover. The pedicle was gradually divided over the ensuing 7 to 14 days before full flap inset and removal of the external fixators. In all three patients, the flaps survived with no complications and successful coverage of the critical defect was achieved. One patient developed a grade 2 pressure injury on his heel that resolved with conservative dressings. The donor sites and external fixator pin wounds healed well, with no functional morbidity. The cross-leg extended distally based sural artery flap is a reliable reconstructive option in challenging scenarios. Adequate flap delay, manoeuvres to reduce congestion, and postoperative rigid immobilization are key to a successful outcome.

• 한국환경복원기술학회지
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• 제19권1호
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• pp.61-71
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• 2016

The purpose of the research is to identify the optimal seeding quantity of Lespedeza cyrtobotrya and Indigofera pseudo-tinctoria as leguminous woody plants for the cut-slope revegetation. To investigate the coverage ratio and appearance frequency, we divided Lespedeza cyrtobotrya and Indigofera pseudo-tinctoria into five treatment groups with various quantities of $0.0g/m^2$, $1.0g/m^2$, $2.4g/m^2$, $3.8g/m^2$, and $5.2g/m^2$. For each treatment group, we mixed the identical quantities of herbaceous flowers (Lotus corniculatus var. japonicus, Dianthus sinensis, Aster yomena and Pennisetum alopecuroides) seeds and cool-season turfgrasses (Festuca arundinacea and Poa pratensis) seeds. In this result, as the seeding quantity of Lespedeza cyrtobotrya and Indigofera pseudo-tinctoria increased in the spray, the coverage ratio for leguminous woody plants appeared to increase whereas the coverage ratio decreased in herbaceous flowers and cool-season turfgrasses. However, when the seeding quantity of Lespedeza cyrtobotrya and Indigofera pseudo-tinctoria exceeded $3.8g/m^2$ in the spray, the coverage ratio of leguminous woody plants rather decreased compared to four treatment groups less than $3.8g/m^2$ seeding ratio. Based on the longitudinal data of coverage ratio in five treatment groups, we observed the gradual process of a short-term succession in which the dominant species shifted in the following order: First, cool-season turfgrasses; Second, herbaceous flowers; Third, leguminous woody plants. Comparing the appearance frequency of Lespedeza cyrtobotrya and Indigofera pseudo-tinctoria, Lespedeza cyrtobotrya appeared more frequent in 2014 whereas Indigofera pseudo-tinctoria appeared to be relatively more frequent in 2015. As a result, Indigofera pseudo-tinctoria was discovered to be a dominant species among woody plants. In this study, we observed that the optimal seeding quantity of Lespedeza cyrtobotrya and Indigofera pseudo-tinctoria was $2.4g/m^2{\sim}3.8g/m^2$. Moreover, the coverage ratio of 29.1%~35.4% and appearance frequency of 4.6plants~5.8plants were found in the condition of optimal seeding quantity.

• 통상정보연구
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• 제8권3호
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• pp.99-119
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• 2006

The recent trend in the payment terms of international trade shows the gradual shift toward more diversified payment methods (from L/C to not L/C) in order to cope with the increasingly dynamic international transactions in a more flexible manner. The reasons behind this recent shift are as follows : first, the global trade market is breaking away from the traditional L/C methods based on letters of credit toward a not L/C methods. nother reason for the changing trade payment methods is the increasing volume of intra transactions between headquarters and their foreign subsidiaries based on collection payment methods. Having mentioned the above problems that impede the Korean export insurance system, some suggestions can be put forward through a comparative analysis with foreign export insurance system. First, inducing private investments is one way of strengthening financial health of the KEIC. The KEIC also needs to diversify its insurance coverage adapting to the changing international trade environments.

• Clinical and Experimental Pediatrics
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• 제55권12호
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• pp.455-461
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• 2012

Following the Five Year Measles Elimination Program, measles has been declared eliminated from the Republic of Korea since 2006. However, there remain challenges related to the surveillance of measles in the postelimination phase. Even though the routine surveillance system has revealed a gradual decrease in the number of reported cases since 2002, 4 resurgences have occurred, notably due to outbreaks. Because vaccine-modified measles is becoming widespread due to high vaccination coverage, conducting laboratory confirmation in each case becomes important. Moreover, susceptible individuals with measles have been identified through seroprevalence studies. Lastly, the efforts to improve the timeliness of measles reporting have led to the establishment of an active laboratory-based surveillance network, which has shortened the interval between diagnosis and notification. In these circumstances, searching for more sensitive and effective surveillance measures is important for maintaining the elimination status and preventing future outbreaks of measles in Korea.