• 한국해양공학회지
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• 제28권2호
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• pp.160-166
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• 2014

Because of industrial development, industrial facilities are becoming more complex and diversified. Plant industries are focused on productivity improvement, cost reduction, and product uniformity by simplifying production processes using automated control. Furthermore, plant industries require higher pressures and temperatures to improve energy efficiency. For this reason, the valves used in plants are operated under harsh conditions. Globe valves and gate valves are mainly used for high pressure these days. However, these valves have various problems, including low maintainability and high cost, due to structural problems. Therefore, butterfly and ball valve applications are increasing in industrial plants. This paper suggests a quadruple-offset butterfly valve that is applicable to bi-direction use, and the principle design parameters are suggested. The selected design parameters are an eccentric flange center line and shaft centerline(Offset 1), an eccentric seat centerline and disc shaft centerline(Offset 2), the angle between the flange centerline and seat wedge angle(Offset 3), the angle between the vertical direction of the disc shaft centerline and seat centerline(Offset 4), and the seat engagement angle. To analyze the interaction effect of the design parameters, ANOM and ANOVA were performed with an orthogonal array. The parameters were found to have effects in the following order: Offset 2, Offset 1, engagement angle, Offset 3, and Offset 4. The interaction between the parameters was insignificant.

• Smart Structures and Systems
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• 제26권3호
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• pp.345-360
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• 2020

Modern swarm intelligence heuristic search methods are widely applied in the field of structural health monitoring due to their advantages of excellent global search capacity, loose requirement of initial guess and ease of computational implementation etc. To this end, a hybrid strategy is proposed based on butterfly optimization algorithm (BOA) and differential evolution (DE) with purpose of effective combination of their merits. In the proposed identification strategy, two improvements including mutation and crossover operations of DE, and dynamic adaptive operators are introduced into original BOA to reduce the risk to be trapped in local optimum and increase global search capability. The performance of the proposed algorithm, hybrid butterfly optimization and differential evolution algorithm (HBODEA) is evaluated by two numerical examples of a simply supported beam and a 37-bar truss structure, as well as an experimental test of 8-story shear-type steel frame structure in the laboratory. Compared with BOA and DE, the numerical and experimental results show that the proposed HBODEA is more robust to detect the reduction of stiffness with limited sensors and contaminated measurements. In addition, the effect of search space, two dynamic operators, population size on identification accuracy and efficiency of the proposed identification strategy are further investigated.

• 한국해안·해양공학회논문집
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• 제26권6호
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• pp.359-366
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• 2014

본 연구에서는 버터플라이밸브의 고유 유량 특성을 개선하기 위해 회색 관계분석을 이용한 디스크 형상 최적화 방안을 도입하였다. Class 150의 200A 버터플라이밸브에 대해 적용하여 그 유용성을 확인하였다. 부가물 형상 파라미터의 영향 분석을 위해 직교 배열을 이용한 실험계획법을 실시하였으며, 파라미터의 영향을 회색 관계 분석과 평균 분석을 이용하여 분석하였다. 최적화를 위한 목적함수는 유량 계수를 선정하였으며, 기존 디스크 모델과 부가물 부착 모델에 대해 유동 해석을 수행하였다. 회색 관계 등급을 이용하여 평균 분석을 실시하였으며, 그 결과를 토대로 최적 형상을 결정하였다.

• 한국경제지리학회지
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• 제14권2호
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• pp.99-115
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• 2011

본 연구는 우리나라에서 개최되고 있는 지역축제의 공간분포를 거시적으로 파악하고, 사례연구를 통해 지역축제가 지역경제에 미치는 파급효과를 미시적으로 고찰하였다. 2009년 현재 전국에서 893개의 지역축제 개최되고 있고, 이들 축제의 대부분은 1995년 이후에 발굴된 신생축제이다. 지역축제의 공간분포는 뚜렷한 지역적 차이를 보이고 있는데, 제주, 경남, 울산, 충남의 기초지자체에서는 축제가 많이 개최된 반면, 경북, 전남, 광주, 경기 등은 상대적으로 적었다. 문화관광 부가 선정한 우수축제인 문화관광축제는 1997년 10개에서 2009년 57개로 증가하였고, 우수축제 1개가 지역경제에 미친 파급효과도 2002년 142.5억 원에서 2008년 333.4억 원으로 확대되었다. 금산인삼축제, 무주반딧불축제, 함평나비 축제를 사례로 지역경제에 파급효과를 분석한 결과, 이들 3개 축제는 관광객 유인에 성공하였고, 지역경제에 미치는 파급효과가 매우 높게 나타났다. 금산인삼축제는 우리나라의 대표적인 산업축제로, 반딧불축제와 나비축제는 생태관광축제로 평가받고 있다.

• International Journal of Industrial Entomology and Biomaterials
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• 제28권1호
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• pp.1-4
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• 2014

The effect of an artificial diet on developmental rate, a life history parameter, was examined for the swallowtail butterfly Papilio xuthus. Artificial insect diets are an essential component of many insect rearing systems that produce insects for research purposes. Complex agar-gelled diets are generally prepared in large batches and used shortly after preparation because the degradation of perishable diet ingredients, such as vitamins and fatty acids, can adversely affect insect quality (Brewer 1984). However, the timing of diet preparation may be inconvenient, and large batches wasteful, if the unused excess is discarded. The percentage of pupation varied considerably, with no significant differences among diets, on which a maximum pupation percentage of 83% was observed. Pellet-type diets were investigated with the aim of developing a more easily prepared diet. The extrusion of the artificial diet under high temperature and pressure may induce desirable chemical and physical changes in the extruded product. The purpose of the present study was to develop an artificial diet for rearing P. xuthus.

• 경영과학
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• 제15권2호
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• pp.239-257
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• 1998

Facing the globalization of world economy, intense market competition, radical change of information technology, firms are obliged to create a new type of organizations characterized by flexibility and adaptability to new and dynamic environments. This paper reviews the theories of complexity in physics briefly and discusses the implications of them on the management of business organizations. It analogizes the core concepts from complexity theories such as cooperative phenomena, self-organization, adaptation, positive feedback, and butterfly effect, and attempts to identify their implications on business management. Particularly, it suggests principles of 'Fractal' management which apply the fractal structure to the business organization.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.911-914
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• 2003

As high-capacity disk drives pow in track density, the allowable level of PES is becoming smaller. In this paper, some design concept of actuator is introduced to suppress the Butterfly mode that imposes the fundamental limitation on servo bandwidth. The effect of dynamics of proposed actuator on PES is examined by simulation.

• 대한전기학회논문지
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• 제34권10호
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• pp.399-406
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• 1985

In this paper transparent PLZT ceramics for the composition of 9/65/35 (La/Zr/Ti ) are fabricated using hotpress and the possibility of application to optical shutter is examined by obtaining the On-Off characteristics of specimens. The ferroelectric E-P hysteresis loop exhibits slim loop suitable for the quadratic electrooptic effect. Measurements of the electrooptic effect show that specimens have the quadratic electrooptic effect but the light intensities as functions of electric field exhibit butterfly type hysteresis curves because of its slightly large saturation remanent polarization and coercive field. On-Off characteristics are obtained by electric fields of-6 kv/cm and +2kv/cm. As a result of experiments, 9/65/35 PLZT ceramics can be applied to optical shutter but construction with other composition which has more slim hysteresis loop is desired for obtaining the Off state by zero electric field.

• 환경영향평가
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• 제23권5호
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• pp.337-352
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• 2014

본 연구의 목적은 우리나라의 대표적 환경축제인 함평나비축제를 대상으로 환경축제가 지역주민의 충성도 제고라는 측면에서 지향해야 할 방향과 과제를 모색하는 것이다. 이에 지역주민을 대상으로 지역사회 애착도와 같은 축제의 외생적 요인과 축제의 경제 효과, 개최자와 지역주민 간의 의사소통, 그리고 지역주민의 축제 참여의사 같은 내생적 요인이 축제의 만족도 및 충성도에 미치는 영향과 경로를 구조 방정식모형을 통해 분석하였다. 분석 결과 애착도, 참여의사, 의사소통은 축제의 만족도에 정(+)의 영향을 미치고, 이 중 애착도는 충성도에도 정(+)의 영향을 미치며, 만족도는 충성도에 정(+)의 영향을 미칠 것이라는 본 연구의 가설은 유의수준 0.05에서 통계적으로 유의한 것으로 판명되었다. 다만 경제 효과는 연구가설과는 달리 만족도에 별다른 영향을 주지 않는 것으로 분석되었다. 한편 충성도에 미치는 총 영향력은 애착도, 의사소통, 참여의사 보다 만족도가 월등히 높은 것으로 나타났다. 그러므로 충성도 제고를 위해서는 원천적으로 애착도 제고, 의사소통 활성화, 참여의사 제고가 긴요하겠지만 이는 장기적으로 꾸준히 추진해야 할 과제일 것이며 단기적으로는 무엇보다도 만족도 제고에 노력하여야 한다.

• International Journal of Industrial Entomology and Biomaterials
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• 제23권2호
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• pp.215-221
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• 2011

To establish an indoor-rearing system for the Large Copper butterfly, $Lycaena$ $dispar$ and the Small Copper butterfly, $Lycaena$ $phlaeas$, the effect of temperature, photoperiod and host plants on larval development was investigated. The larvae of $Lycaena$ $dispar$ fed on $Rumex$ $crispus$, whereas the larvae of $Lycaena$ $phlaeas$ ate both $Rumex$ $crispus$ and $Rumex$ $acetosa$. The duration of the larval period of $Lycaena$ $dispar$ was 13.8 days on $R.$ $crispus$ and that, of $Lycaena$ $phlaeas$ was 15.9 days and 15.2 days on $R.$ $acetosa$ and $R.$ $crispus$ respectively. Laboratory experiments show that the Large Copper larvae are able to feed on other $Rumex$ species without harming their overall survival and can utilize these alternative host plants at least as efficiently as their natural host plant. This result suggests that plant chemistry is not responsible for their lack of utilization of the alternative host plants in the wild. Host plant choice by ovipositing females was measured with the two alternative hosts. $Lycaena$ $dispar$ preferred $R.$ $crispus$ to $R.$ $acetosa$, wheareas $Lycaena$ $phlaeas$ preferred $R.$ $acetosa$ to $R.$ $crispus$. Temperature has been proposed as an important determinant of developmental rate, lifespan and mortality in invertebrates. As temperature increased, length of the developmental period gradually decreased. The developmental period of the Large Copper larvae was 11.0 days and 28.5 days at $30^{\circ}C$ and $17.5^{\circ}C$, respectively.