• 신재생에너지
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• 제10권3호
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• pp.47-54
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• 2014

Recently, BESS is considered as one of essential countermeasure for demand side management. However, an economic evaluation is critical issue for the introduction of power system because the cost of BESS is very high in present stage. Therefor, this paper presents economic evaluation method for customer use case by considering peak shaving function based on the real time price. From the case study on the model power system and educational customer, it is confirmed that the proposed method is a practical tool for the economic analysis of BESS. and analytical approach for the reliability assessment in radially operated distribution systems. The approach can estimate the expected reliability performance of distribution systems by a direct assessment of the configuration of the systems using the reliability indexes such as NDP (Non-Delivery Power) and NDE (Non-Delivery Energy). The indexes can only consider the number and configuration of the load, but can not consider the characteristics of the load which is the one of the most important factor in the investment cost for the distribution systems. Therefore, this paper presents the new performance indexes for the investment of the distribution facilities considering both the expected interruption cost for the load section and the operation characteristics of Energy Storage System. The results from a case study show that the proposed methods can be a practical tool for the reliability management in distribution systems including Energy Storage System.

• 전기학회논문지
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• 제63권8호
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• pp.1070-1074
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• 2014

With the development of the electronics industry and widespread supply of many different electrical appliances, the factors of the electrical fires are also diversified. For this reason, the fuse, safety-critical component, needs accurate and stable operating characteristics for preventing various fire factor, and also needs various operating characteristics. Especially when the all electrical resistance are dropped by internal short of circuit, high current inrushes and makes the fire. In order to prevent this, very fast acting fuses should be applied. However, existing very fast acting characteristics fuse has less wire dimension of element Ag100% metal than that of fast acting fuse, and it is made of plating with low melting point metals, so it satisfy very fast acting but it can't satisfy durability and safety. For this reason, in this study, through the analyzing fusing characteristics of Ag-Cu alloy composition, the new alloy composition, which implement to very fast acting fuse without decrease of fuse elements dimension, is suggested. And this study classify the operating characteristics changes, a resistance change, and the rated current of the fuse in the overall composition change of Ag-Cu alloying. and it can be utilized for designing fuse.

• Journal of Microbiology and Biotechnology
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• 제16권5호
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• pp.695-703
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• 2006

The dissolved oxygen level of any cell culture environment has a critical effect on cellular metabolism. Specifically, hypoxia condition decreases cell viability and recombinant protein productivity. In this work, to develop CHO cells producing recombinant protein with high productivity, mammalian expression vectors containing a human tissue-type plasminogen activator (t-PA) gene with hypoxia response element (HRE) were constructed and stably transfected into CHO cells. CHO/2HRE-t-PA cells produced 2-folds higher recombinant t-PA production than CHO/t-PA cells in a $Ba^{2+}-alginate$ immobilized culture, and 16.8-folds in a repeated batch culture. In a non-aerated batch culture of suspension-adapted cells, t-PA productivity of CHO/2HRE/t-PA cells was 4.2-folds higher than that of CHO/t-PA cells. Our results indicate that HRE is a useful tool for the enhancement of protein productivity in mammalian cell cultures.

• 경영정보학연구
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• 제9권1호
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• pp.259-282
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• 2007

본 연구는 조달청의 종합성과관리시스템에 대한 사례를 제시하는 것이다. 조달청은 최초 구축한 성과관리시스템의 개선 및 보완 작업을 통해 2006년 초에 BSC 시스템을 구축하였으며, 그 결과 미션과 비전과 전략과제로부터 도출된 CSF와 KPI의 활용을 통해 부서와 개인에 대한 성과측정과 평가를 자동적으로 연계할 수 있게 되었다. 이는 공무원도 기업처럼 성과에 따른 보상을 함으로써 더욱 향상된 고객서비스를 제공하고, 평가 결과를 통하여 인사, 보수 등에 있어서 인센티브와 디스인센티브를 적절히 활용하여 경쟁과 성과보상의 조직으로 확고한 자리를 잡고자 하는 데 기여하였다. 또한BSC 구축은 부서중심의 개인평가체계의 강화, 다양한 평가체계에 대한 통합구성 및 실적주기별 목표관리에 의한 달성률 모니터링 체계의 구축을 가능하게 하였다. 이와 같은 조달청에 대한 사례 제시는 향후 다른 공공조직의 BSC 구축에 대한 방향을 제시할 것이며, 성과관리시스템 구축 방안과 성공요인에 시사점을 줄 수 있을 것으로 기대된다.

• 한국지진공학회논문집
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• 제6권3호
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• pp.53-62
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• 2002

지반조건은 구조물의 지진거동에 매우 큰 영향을 미치고 성능에 기준한 내진설계에 중요한 요소이다. 이 논문에서는 지진에 의한 지반의 비선형성을 포함한 지반의 비선형성이 구조물의 탄성지진거동에 미치는 영향을 지반 구조물 일괄해석 유한요소법과 지반의 비선형성을 구현하기 위해 Ramberg-Osgood 토질모델에 대한 근사선형 반복해석법으로 연구하였다. 연구는 말뚝기초의 유무를 고려한 주기가 변하는 선형 단자유도계에 지표에서 기록된 1940년 EI Centre지진을 적용하여 수행하였다. 연구결과에 의하면 연약지반의 비선형 특성 영향이 구조물의 탄성 지진거동에 매우 중요하곡 성능에 기준한 지반의 비선형성을 고려한 구조물의 내진설계가 필요하다는 것을 잘 보여주고 있다.

• 환경영향평가
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• 제7권2호
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• pp.103-112
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• 1998

일본에서는 자연친화형 하천사업을 많이 시행하고 있다. 바람직한 수환경을 보전하고 복원하기 위해서는 하천내외의 생태계에 대한 수질기준을 정립하여야 한다. 본 논문에서는 생물학적 지표를 사용한 수질 분류 방법을 개발하여 나가사키현의 혼묘하천에 대하여 적용하였다. 이러한 수질 분류를 위하여, 수정된 오염물 지표 분류법을 제안하였다. 비교적 단순한 방법이지만, 가장 많은 종에 대한 3가지 지표만으로 수질을 효과적으로 평가할 수 있었다. 또한, 하천유역의 통합관리를 위하여 다양한 생태계 자료를 포함하는 종합적인 자료관리시스템을 개발하였다. 본 시스템을 사용하여 건전한 수환경을 보전하기 위한 각종 생태계 자료를 쉽게 취득할 수 있다. 본 연구의 결과를 사용하여 수질자료를 개선하고, 시민들의 의식을 고양하며, 하천관리계획을 세울 수 있을 것이다. 일본에서는, 자연친화적 하천복원사업에 있어서 시민들의 의식 및 행동이 가장 중요한 요소이다.

• 대한의용생체공학회:의공학회지
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• 제34권1호
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• pp.14-23
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• 2013

In this study, biomechanical stability of the newly developed revision total knee arthroplasty (rTKA) was evaluated through strain and stress distribution analysis within the implanted proximal tibia using a three-dimensional finite element (FE) analysis. 2000N of compressive load (about 3 times body weight) was applied to the condyle surface on spacer, sharing by the medial (60%) and lateral (40%) condyles simulating a stance phase before toe-off. The results showed that PVMS within the revision total knee arthroplasty and the proximal tibia were less than yield strength considering safe factor 4.0 (rTKA: less than 10%, Cortical bone: less than 70%, Cancellous bone: less than 70%). The materials composed of them and the strain and stress distributions within the proximal tibia were generally well matched with those of a traditional revision total knee arthoplasty (Scorpio TS revision system, Stryker Corp., Michigan, USA) without the critical damage strain and stress, which may reduce the capacity for bone remodeling, leading to bone degeneration. This study may be useful to design parameter improvement of the revision total knee arthoplasty in biomechanical stability point of view beyond structural stability of revision total knee arthoplasty itself.

• 한국정보시스템학회지:정보시스템연구
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• 제20권4호
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• pp.49-72
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• 2011

Business Process Change(BPC) is regarded as a salient factor to improve an organizations' efficiency in the current fast-changing business environment. Despite the tremendous popularity and great potential, the field of BPC adoption is littered with remarkable failures. Consequently, there have been many studies that have tried to identify the environmental factors that lead to successful BPC. However, most of them have not considered the effect of the interaction between the environmental factors on BPC success. According to Klempa(1995), the fit between environmental factors of a company may have the impact on its BPC success. Under this background, this paper empirically examines the effects of the fit between the type of BPC and the organization's culture on the success of BPC. Organization's cultures, organizational learning, as well as knowledge sharing are the dominant causes that have impact on the innovation characters of organization. Whether an organization has safety-oriented homogeneous culture or it has the change-oriented heterogeneous culture may have impact on its implementation of BPC. Also the implementation of BPC may be affected by whether the organization adopts the improvement project which accompanies only small changes or it adopts the innovation project which leads to critical changes. Thus, we analyzed the effect of the fit between the organization's culture and its BPC type on BPC success by using the survey data collected from the companies that have adopted BPC. The findings presented in this paper show that the organization having heterogeneous culture practicing innovation project and the organization having homogeneous culture practicing the improvement project resulted in the excellent BPC success.

• 폴리머
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• 제37권4호
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• pp.449-454
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• 2013

본 연구에서는 무전해 니켈도금에 따른 탄소나노튜브의 표면특성변화가 알루미나강화 에폭시 복합재료의 열전도도 및 파괴인성에 미치는 영향에 대하여 살펴보았다. 무전해 니켈도금된 탄소나노튜브의 표면특성은 주사전자현미경(SEM), X-선 광전자분광기(XPS), X-선 회절분석(XRD)을 통하여 알아보았다. 열전도도는 열전도율 측정 시스템으로 측정하였고, 파괴인성은 만능시험기(UTM)를 이용한 임계응력세기인자($K_{IC}$)를 측정하여 분석하였다. 실험결과, 무전해 니켈도금은 탄소나노튜브의 표면특성의 변화를 가져오며, 니켈도금된 MWCNTs(Ni-MWCNTs)가 들어있는 경우 미처리 MWCNTs와 비교하여 우수한 열전도도 및 파괴인성을 보였다. 이는 Ni-MWCNTs와 에폭시수지와의 분자간 상호작용의 향상 때문이라 판단된다.

• 한국학교보건학회지
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• 제34권1호
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• pp.62-75
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• 2021

Purpose: Smoking among adolescents is a critical healthcare concern that needs to be tackled with respect to not only intrapersonal and interpersonal factors but also socio-cultural factors. This study was to identify the smoking behaviors and amount of tobacco consumption among adolescents, and to investigate the factors associated with the behaviors and amount. Methods: A cross-sectional study was conducted based on the theory of triadic influence using a nationally representative secondary data set, the 2018 Korea Youth Risk Behavior Survey (N=60,040). The analysis was performed by dividing smoking behaviors into lifetime, current, and daily smoking, and smoking amount into light, moderate, and heavy smoking. Descriptive statistics and multinomial logistic regression analyses were conducted. Results: Overall, 8.2%, 3.2% and 3.4% of the adolescents were involved in lifetime, current, and daily smoking, respectively. In addition, 5.3%, 0.8%, and 0.6% of the adolescents were involved in light, moderate, and heavy smoking, respectively. The factor associated with smoking behaviors and the amount of tobacco consumed were gender, academic achievement, depression, living with family, close friend's smoking, violent victimization, household economic status, and school level (all ps<.05). Conclusion: A considerable number of adolescents are engaged in risky smoking behaviors and consume large amounts of tobacco. Adolescents who said yes to peer smoking, violent victimization, not living with their family, and depressive emotions were more likely to engage in risky smoking behaviors and consume large amounts of tobacco. Tailored interventions to decrease smoking should be planed and provided, while considering the school and home environment and individual needs of adolescents.