• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.297-299
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• 2014

Petroleum coke has high heating value and low price. Due to the steadily increasing demand for heavy oil processing, the production volume of petroleum coke tends to be expanded. The high availability and low price of petroleum coke have been strongly considered as candidate fuel for power generation facilities. However the high carbon content, high sulfur content and nitrogen content of petroleum fuel are known to produce relatively large quantity of CO2, high NOx and SO2 emission. In this work, a series of numerical simulations have been carried out in order to investigate the effects of swirl flow intensity on combustion furnace, which is most important operating condition. Results show that the temperature distribution was spatially uniform at about 1600K but high temperature region are located quite differently depending on swirl number. In addition, numerical temperature data was compared with experimental temperature data and its temperature difference shows less than 10%. On the other hand, discrepancy between numerical and experimental emission data were slightly large with necessities of improved emission model.

• Korean Journal of Geomatics
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• 제2권1호
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• pp.7-15
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• 2002

Recent development of ultra-high and high degree Earth geopotential model opens new avenues to determine the Earth gravity field through spectral techniques to a very high accuracy and resolution. However, due to data availability, quality, and type, the performance of these new EGMs needs to be validated in regional or local scale geoid modeling. For establishing the best reference surface of geoid determination, recent geopotential models are evaluated using GPS/Leveling-derived geometric geoid and the Korean gravimetrical GEOID (KGEOID98) developed by National Geography Institute in 1998. Graphical and statistical comparisons are made for EGM96, GFZ97, PGM2000A and GPM98A models. The mean and standard deviation of difference between geometric height and geoid undulation calculated from GFZ97 are $1.9\pm{46.7}\;cm$. It is shown that the GFZ97 and the GPM98A models are better than the others in the Korean peninsula because the GFZ97 has a smaller bias. It means that the KGEOID98 needs some improvement using the GFZ97 instead of EGM96.

• Asian Journal of Innovation and Policy
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• 제7권1호
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• pp.55-78
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• 2018

This paper investigates the linkage between the mode of transformation of entrepreneurial learning into outcomes and the subsequent impact of these learning outcomes in enhancing the survival of high-tech startups in India. The study uses data from 45 high-tech startups headquartered across different locations in India for the purpose of analysis. Survival Analysis of the data is conducted to determine which mode of learning transformation and what type of en trepreneurial decision making preference have a significant influence on the survival of Indian high-tech startups and to what extent do they impact their survival. The results indicate that entrepreneur's prior startup experience, explorative mode of learning transformation, causal decision making of the entrepreneur and availability of funding for the startup as the key factors that reduce the time to survival of Indian high-tech startups. They also provide key insights on how these factors impact the startup survival in this region.

• 농업과학연구
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• 제45권3호
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• pp.325-353
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• 2018

Agricultural systems in South Asian countries are dominated by smallholder farmers. Additionally, these farmers have limited access to pre- and post-harvest technologies due to their high initial cost. The lack of these technologies in postharvest handling is responsible for 20% to 44% of fruit and vegetable losses. These high losses are largely the result of a generally weak basic postharvest infrastructure for the preservation of products, which avoids damage from improper handling, transportation, packaging, and storage. High postharvest losses of products negatively affect food availability, food security, and nutrition, as the producer is able to sell less of the farm yield and the net availability of these food commodities for consumption is reduced. An underlying cause of these postharvest losses is the limited awareness and knowledge bases of stakeholders (researchers, farmers, governments, non-governmental organizations, and merchants) in the traditional supply chains in which these losses occur. The analysis presented in this paper explores the state of postharvest practice in South Asian countries and discusses options for low-cost postharvest technologies in the region that can support small-scale farmers and provide a viable pathway for supply to the market, joining with modern value chains and bringing about individual and regional reduction in postharvest losses of fruits and vegetables. The improvement of basic and simple low-cost technologies through precise research efforts has the potential to prevent such huge losses of products, and help meet the ever-increasing demand for food in South Asian countries.

• 한국공간정보시스템학회 논문지
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• 제6권1호
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• pp.3-17
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• 2004

웹을 통해 위치기반 서비스 등과 같은 다양한 지리정보 서비스를 사용하려는 사용자가 급격하게 증가하면서, 웹 지리정보시스템도 많은 다른 인터넷 정보시스템들과 같이 클러스터 기반 아키텍쳐로의 변화가 요구되고 있다. 즉, 사용자의 수에 상관없이 양질의 지리정보 서비스를 지속적이며 빠르게 제공하기 위해서는 비용대비 효율, 가용성과 확장성이 높은 클러스터 기반의 웹 지리정보시스템이 필요하다. 본 논문에서는 가용성과 확장성이 높은 클러스터 기반의 웹 지리정보시스템을 설계한다. 이를 위해 메모리 상주 공간 데이터베이스들을 클러스터의 각 노드로 구성하고 전체 데이터 영역 중 일부만을 복제 처리함으로써, 각 노드가 공간 질의에 대해 공간적 근접성을 이용한 캐시 역할을 수행하도록 한다. 또한, 제안된 시스템은 단순 영역 질의외에 연산 비용이 큰 공간 조인 연산을 효율적으로 처리한다. 본 논문에서는 성능평가를 통해 제안된 기법이 기존 기법에 비해 데이터 양이 많고, 클러스터의 노드 수가 증가할수록 각각 약 23%, 30%의 향상된 성능을 갖음을 보인다.

• 재활간호학회지
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• 제5권1호
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• pp.27-37
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• 2002

During acute stages of hospitalized stroke patients, family caregivers face many challenges. They often experience emotional distress, social isolation, and financial constraints. However, the burden of caregiving of stroke patients in acute stages has never been studied properly. The purpose of this study was to investigate the factors related to the caregivers' burden with acute stroke. The subjects were 123 acute stroke patients and their caregivers who were admitted to neurology and neurosurgery units at Dan Kook University Hospital in Chung-Nam area. An interview was performed with the use of standardized questionnaire which included data pertaining to the patients/caregivers characteristics, caregiver burden (Modified Zarit's Burden Scale), and social support (Personal Resource Questionnaire). Our results showed that the mean burden score was 3.11, indicating high level of burden. Among the sub-domain scores, financial burden was the highest. In univariate analysis, the factors related to caregiver burdens were: inability to communicate between patients and caregiver(p<.001); low cognitive function of the patients(p<.001); low level of ADL(p<.001); the gender of caregiver(p<.001); the current employment status of caregivers(p<.01); the presence of social support for caregiver(p<.001); and the availability of alternative caregivers(p<.001). In multiple regression analysis, social support for family caregivers (87%), low level of patient's cognition (2%), availability of 2nd caregiver (1%), and gender of caregiver (female, 0.4%) were significant explanatory factors of overall burden. The caregivers' burden in acute stages during hospitalization following stroke was high. Recognition of high levels of caregivers' burden and those relating factors affecting caregiver burden may allow us to develop different nursing strategies to unload the level of burden for caregivers in acute stages of stroke.

• 한국정보통신학회논문지
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• 제20권12호
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• pp.2267-2273
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• 2016

본 논문에서는 OSMU (One Source Multi Use) N-스크린 멀티캐스트 서비스를 위한 무선 통신 MAC 구조로서, WiMedia Distributed-MAC 프로토콜을 적용하였다. 그러나, 채널 에러율이 가변적인 무선 통신환경을 고려하면, N-스크린 고속 데이터가 손실될 가능성이 높다고 할 수 있다. 이러한 문제에 대해, WiMedia Distributed-MAC 프로토콜을 분석하여, 멀티캐스트 릴레이 기술을 제안하였다. 제안하는 멀티캐스트 릴레이 기술은 Multicast-free DRP Availability IE 기술과 결합되어, 멀티캐스트 통신에 대해 릴레이노드를 선정하고 에러율이 높은 채널을 회피하여 통신할 수 있다. 시뮬레이션을 통해 제안하는 멀티캐스트 릴레이 기술과 기존 WiMedia Distributed-MAC 멀티캐스트 기술을 멀티캐스트 노드 수에 따라 수율과 에너지 소모량을 비교 하였고, 다양한 BER (Bit Error Rate) 채널 환경에서 수율 성능을 비교하였다. 이를 통해, OSMU N-스크린 멀티캐스트 서비스에서 멀티캐스트 릴레이 기술이 적용되어야 함을 설명하였다.

• 가정과삶의질연구
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• 제28권3호
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• pp.27-41
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• 2010

In this study, based on the current curriculum of consumer education in high school with the advent of Web 2.0 age, I analyzed both the curriculum used by new information tools related with Web 2.0 age and the one used by traditional tools to find out the degree of necessity of consumer education for the high school students in proportion to the level of their informational ability. First, compared with the education of food, clothes and shelter in the curriculum of manual training and domestic science, the necessity, importance, and availability were low and the students had a lower level of interest than they had with the three factors mentioned above. Second, after dividing the sector of consumer education in the curriculum into three fields such as reasonable purchase and use, solution and prevention of consumer problems and forming a new consumer trend, I looked into the necessity of the teaching method using conventional tools and the one using new informational tools following Web 2.0 age respectively. Traditional tools were favored for the education of consumption-related laws and policies, consumers' rights for the general cause of consumer problem solving and preventing. For the generation of the new comsumer trend, the new information tools were preferred in the appreciation of consuming culture and the issues of consuming environment. Third, it was revealed that students' level of informational ethics was the highest at 5.55 while their level of information creation and processing was the lowest at 3.96 from the research of six categories of their informational ability.

• 정보처리학회논문지D
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• 제10D권6호
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• pp.949-960
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• 2003

기존 디스크 기반 데이터베이스 관리 디스트를 주저장 장치로 활용하는 특징적 환경 때문에 주기억 상주 데이터베이스 관리 시스템의 메모리 관리, 인덱스 관리, 자료저장 관리 기능 등에 대한 설계 및 구현 기술이 기본적으로 다르다. 본 논문에서는 현재 상용 시스템으로 사용되고 있는 $ALTIBASE^{TM}$ 주기억 상주 DBMS 의 설계 및 구현 내용을 기술한다. 특히 자료저장 관리기의 세부 구성요소에 대한 구조적 특징가 주요 기능인 트랜잭션 처리 기법과 회복 관리 기법에 대하여 기존 DBMS 의 기능가 비교 설명하며, 고가용성을 위한 데이터베이스 이중화 기능 및 이중화 작업 시 발생하는 트랜잭션 충돌 해결 방법에 대하여 설명한다. 또한 $ALTIBASE^{TM}$ 시스템의 성능을 측정하기 위하여 다양한 환경에서 실험된 TPS 결과를 보인다.

• 대한지역사회영양학회지
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• 제8권6호
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• pp.867-875
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• 2003

The purpose of this study was to investigate the psychosocial factors influencing dairy product consumption of female university students in Daejeon. The Theory of Planned Behavior provided the basis for this study. As a result of the pilot-study, 18 behavioral beliefs, 8 normative beliefs, and 12 control beliefs were identified. The subjects (n=236) were grouped into a high-consumption group (1 serving/day, n=117) and a low consumption group (< 1 serving/day, n=119). The data were analyzed using t-tests or $\chi$$^2$-tests. Among the general characteristics, there were significant differences in the amount of pocket money spent per month, residence type (p<0.01), weight, frequency of exercise and perceived health status (p<0.05) of the subjects. With respect to the 18 behavioral beliefs, the high consumption group responded less negatively on ‘eating dairy foods would not be convenient’ than the low consumption group (p<0.05). None of the subjective normative items were significantly different between the two groups. However, notable differences were found in regard to the control beliefs (8 out of 12 control beliefs). These included overall control over consuming dairy products (p< 0.001), as well as specific beliefs regarding barriers such as easy spoilage of dairy products, the cost, eating them for snacks and dislike for them (p<0.05). In addition, specific situations, such as ‘when I want them I get them’ (p<0.01), eating out and the availability of dairy foods at home (p<0.05) were significantly different between the two groups. The high consumption group showed more control over these barriers or situations. These results suggest that nutritional education for young female adults should incorporate strategies to increase their perceived control over the consumption of dairy products by removing barriers and including environmental approaches which address the availability issues.