• 천문학회보
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• 제35권1호
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• pp.87.2-87.2
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• 2010

Near-Earth asteroid-comet transition object 4015 Wilson-Harrington is a possible target of the joint European Space Agency (ESA) and Japanese Aerospace Exploration Agency (JAXA) Marco Polo sample return mission. 4015 W-H was discovered showing cometary activity by Albert G. Wilson and Robert G. Harrington at Palomar Observatory in 1949. After recovered in 1979, 4015 W-H has been observed at every apparition, it always was seen as a point source. We made time series observations for 4015 W-H using the 1.8m telescope with 2K CCD at Bohyunsan Observatory, on the nights of 2009 November 17-19. The geocentric distance of 4015 H-W was about 0.38 AU at that time. No trace of cometary activity is seen from our images. From the light curve analysis, we find a double-peaked rotational period of 2.2 hours with amplitude of 0.4 magnitude. Our result is much shorter than previous measurements of 3.6 hours (Harris & Young 1983) and 6.1 hours (Osip et al 1995). We will discuss possible origin of the period variations.

• International Journal of Automotive Technology
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• 제7권3호
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• pp.369-375
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• 2006

This paper describes a simple proportional and integral control algorithm for a swirl motor controller and its application. The control algorithm may be complicated in order to have desired performance, such as low steady state errors, fast response time, and relatively low overshoot. At the same time, it should be compact so that it can be easily implemented on a low cost microcontroller, which has no floating-point calculation capability and low computing speed. These conflicting requirements are fulfilled by the proposed control algorithm which consists of a gain scheduling proportional controller and an anti-windup integral controller. The mechanical friction, which is caused by gears and a return spring, varies very nonlinearly according to the angular position of the system. This nonlinear static friction is overcome by the proportional controller, which has a two-dimensional look up gain table. It has error axis and angular position axis. The integral controller is designed not only to minimize the steady state error but also to avoid the windup effect, which may be caused by the saturation of a motor driver. The proposed control algorithm is verified by use of a commercial product to prove the feasibility of the algorithm.

• 한국국방경영분석학회지
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• 제26권1호
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• pp.89-99
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• 2000

This paper deals with a heuristic algorithm for the vehicle routing-scheduling problem to minimize the total travel distance and the total cost. Because the aim of the Clarke-Wright method, one of famous heuristic methods, is to minimize the total travel distance of vehicles, it cannot consider the cost if the cost and the travel distance is not proportional. In the Clarke-Wright method, the route of each vehicle is found by using the saving matrix which is made by an assumption that the vehicle comes back to the starting point. The problem dealt with in the paper, however, does not need the vehicle to come back because each vehicle has its hoping-start-points and hoping-destination-points. Therefore we need a different saving matrix appropriate to this occasion. We propose a method to find an initial solution by applying network simplex method after transforming the vehicle routing-scheduling problem into the minimum cost problem. Moreover, we propose a method to minimize the total travel distance by using the modified saving matrix which is appropriate to no-return occasion and the method for the case of plural types of vehicles and freights.

• Membrane and Water Treatment
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• 제15권3호
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• pp.107-115
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• 2024

This study proposes the recycling of MVS as a value-added product for the removal of phosphate from aqueous solutions. By comparing the phosphate adsorption capacity of each calcined adsorbent at each temperature of MVS, it was determined that the optimal heat treatment temperature of MVS to improve the phosphate adsorption capacity was 800 ℃. MVS-800 suggests an adsorption mechanism through calcium phosphate precipitation. Subsequent kinetic studies with MVS-800 showed that the PFO model was more appropriate than the PSO model. In the equilibrium adsorption experiment, through the analysis of Langmuir and Freundlich models, Langmuir can provide a more appropriate explanation for the phosphate adsorption of MVS-800. This means that the adsorption of phosphate by MVS-800 is uniform over all surfaces and the adsorption consists of a single layer. Thermodynamic analysis of thermally activated MVS-800 shows that phosphate adsorption is an endothermic and involuntary reaction. MVS-800 has the highest phosphate adsorption capacity under low pH conditions. The presence of anions in phosphate adsorption reduces the phosphate adsorption capacity of MVS-800 in the order of CO 3 2-, SO 4 2-, NO 3- and Cl-. Based on experimental data to date, MVS-800 is an environmentally friendly adsorbent for recycling waste resources and is considered to be an adsorbent with high adsorption capacity for removing phosphates from aqueous solutions. This paper combines the advantages of gray predictor and AI fuzzy. The gray predictor can be used to predict whether the bear point exceeds the allowable deviation range, and then perform appropriate control corrections to accelerate the bear point to return to the boundary layer and achieve.

• 한국양식학회지
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• 제11권4호
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• pp.521-528
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• 1998

자주복 Takifugu rubripes 자어의 섭이상태에 관한 기초 지식을 얻기 위하여 수온 16.5~18.5${\circ}C$ 범위의 급이와 무급이 조건하에서 초기자어의 성장, 생존율 그리고 섭이율 등을 비교, 조사하였다. 자주복 자어는 부화후 5일 전후에서 난황흡수의 내부영양에서 외부영양으로의 전환이 시작되고, 이 시기에 있어 섭이의 유무는 그후 자어의 성장, 생존율에 큰 영향을 미치는 것이 사육실험 결과 밝혀졌다. 무급이 자어는 부화후 16일에 전 개체가 사망하나, 초기사망의 출발점은 유구가 흡수되는 부화후 9일(기아 5일)경부터 추측된다. 급이구와 무급이구 자어의 성장을 비교한 결과, 무급이구에서는 부화후 4일경부터 성장이 정지되고, 부화후 7일이후는 성장 감소를 보였다. 기아상태에 놓여있는 자어의 섭이율 변화는 기아일수 경과에 따른 자어의 유영력과 깊은 관계가 있는 것으로 생각된다. 따라서 자주복 종묘생산시급이 개시시기는 가능한 빨리 결정하는 것이 건강한 종묘의 생산과 높은 생존율을 향상시킬 수 있다.

• 재무관리연구
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• 제26권4호
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• pp.165-189
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• 2009

본 연구는 지분공시와 같은 증권시장의 제도가 투자자의 행태에 미치는 영향에 대하여 분석하였다. 자본시장통합법 개정 이전의 공시규정에 따르면 내부자는 본인의 거래를 공시하는데 있어 매매시점과 공시시점 사이에 공시시차를 가질 수 있다. 따라서 정보거래자는 공시시차를 이용하여 분할매매를 통해 본인의 거래를 은닉할 수 있으며, 분할매매를 용이하게 하기 위해 가능한 공시시차를 길게 가져갈 유인을 갖게 된다. 본 연구에서는 일차적으로 공시시차를 이용한 정보거래자의 전략적 행동이 국내시장에 존재하는가를 살펴보았다. 다음으로 이들의 전략적 행동이 공시일 이후의 초과수익에 미친 영향을 분석하여 이들의 은닉전략이 성공했는가를 분석하였다. 또한 추종거래의 존재를 가정하여 추종거래의 주가 영향력에 대하여도 살펴보았다. 주요 연구결과는 다음과 같다. 즉시공시 의무가 없는 주요주주의 경우 공시시차를 최대한 길게 가져갈 수 있는 월초에 매매를 시작하는 빈도가 다른 시점에 비하여 유의하게 높게 나타났다. 이러한 결과는 정보거래자들이 공시시차를 이용하여 전략적으로 행동한다는 직접적인 증거를 제시해주고 있다. 또한 중규모정보에 있어서 전략변수가 가장 높은 값을 갖는 것으로 나타났다. 그러나 이들이 전략적인 매매를 통하여 초과수익을 실현했다는 실증적 근거는 나타나지 않았다. 한편 매도거래의 경우 매매일 시점에 주가가 과민반응하였으며, 공시일 이후 과도하게 하락한 부분이 회복되는 것으로 나타나 추종거래의 개연성도 있는 것으로 추정된다.

• 안보군사학연구
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• 통권3호
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• pp.121-167
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• 2005

The great strategy of China has been changing depending on the time, change of surrounding environment and personality of leaders of the time. However, the process of the change was not the drastic change but has maintained the consistency through the course of modification and development. The great strategy of Mao Ze-dong was to have the objective in 'World Great Nation' with the facilitation of the 'Surpass Strategy' and 'Autonomy, Independence and Alliance strategy' to successfully build up the political great nation, but he entrapped China's politics and economy into the point of no return by excessive war preparation under 'The Principle of Inevitable World War', striving of rapid communism and other policies. The Deng Xiao-ping era also targeted for ‘World Great Nation’ but, unlike Mao Ze-dong, he had the foundation in the 'The Principle of Evitable World War' and undertook the ‘Peace and Development Strategy’ and ‘Peaceful Coexistence' to build up the advantageous surrounding environment for China to focus on the economic construction as the core of the nation by establishing ‘The Reform and Opening Strategy’ and 'Three-step Development Strategy‘ to have the successful soft landing of the Chinese economy with the astonishing economic development. The system of leader's group of China after Deng Xiao-ping succeeded the practical and realistic spirit of Deng Xia-ping, and based on the drastically grown economic strength, the great strategy of China is on the ‘The Great Reinvigoration of Chinese Nation’. This is one step further from the strategy of 'World Great Nation' of the past that it embraces all the minority races in China, Chinese economic sphere, foreign citizens of Chinese origin as well as Chinese residing abroad. China contemplates the time of making 'The Great Reinvigoration of Chinese Nation’ in 2050, 100 anniversary of the birth of new China.

• 한국의류학회지
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• 제18권3호
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• pp.387-394
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• 1994

Journal of the Korean Society of Clothing and Textiles Vol. 18, No. 3 (1994) p. 387∼394 In this study, the restriction of slacks (blue jean) versus box pleats skirt was investigated, from the view point of peripheral blood flow at the toe according to motion variation and E.M.G. analysis of leg muscles after walking on the flat or going up and down stairways. Besides, the pressure of slacks on the lower extrimity was measured statically and dynamically. The main results were summerized as follows; 1. The clothing pressure applied by slacks was; each one of thigh and lower leg was 18.2 g/ cm2 and 22.1 g/cm2 in upright, 63.4 g/cm2 and 26.6 g/cm2 in sitting on the chair, on both sides of thigh and lower leg 272.0 g/cm2 over in squatting. 2. When the motion starts from upright, the dynamic clothing pressure reach their peak before the motions end. When the motion ends and the body comes to a still condition, the clothing pressure grow lower and indicate a constant value. but when the body starts moving again to return to upright, the pressures once grow higher and go to zero value after reaching the peak. The pressure on the knee show much greater than those on the hip. This can be because these pressures depend on the degree of skin stretching motion and of its curvature. 3. The surface E.M.G. in leg muscles M. rectus femoris and M. gastrocnemius were recoreded. In the case of wearing slacks, two muscles were activated much more than wearing skirt. 4. The peripheral blood flow at the toe by wearing slacks was lower than wearing skirt. Also the case when squatting, the peripheral blood flow at the toe was low.

• 복식문화연구
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• 제19권2호
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• pp.346-359
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• 2011

The purpose of this study was to examine students' reasons and standards for purchasing their casual upper garments through online shoppin. A questionnaire composed of 26 items in five-point Likert type (14 items for measuring reasons, and 12 items for measuring standards for their purchase) was administered. The subjects were 422 male and female students attending middle schools, high schools and colleges located in the metropolitan region of Daegu. For a statistical analysis, a $3{\times}2$ two way ANOVA design (3 levels of schools: middle school, high school and college and 2 sexes: male and female) was involved, and Turkey's HFD multiple comparisons were made. The results showed that the reasons for students' purchasing casual upper garments through online shopping malls were as follows: quality, availability of discount coupons and points, other benefits such as special promotions, gifts, the easy return of goods and refunds, and also no trial of wearing shirts even at off-line stores. Significant differences in purchasing reasons through online shopping were found among middle schoo, high school and college students. There were also significant differences between male and female students mostly found in three variations of purchasing reasons: ease of availability of garments in contemporary fashion, convenient shopping without any restriction on time, and the decision to purchase with help from consumers' recommendations. Significant differences among middle school, high school and college students were found in the following standards for the students' decision to purchase their casual upper garments through online shopping: affordability, color, design, style, payment safety, and ease of maintenance (cleaning and ironing). Differences between male and female students were found to be significant in the following categories: affordability, fashionable, brand name, free delivery, product quality, coordination with other clothes, and consumers' recommendations on the products concerned.

• 철학연구
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• 제143권
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• pp.87-118
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• 2017

이 논문에서 필자는 피터 싱어의 인간 개념에서 발견되는 몇 가지 이론적인 모순점들을 보여줄 것이다. 싱어는 인간을 한편으로는 자연에 종속된 존재로 간주하면서 다른 한편으로는 초월적인 존재로 간주한다. 이것이 그의 인간개념의 첫 번째 비일관성이다. 그의 두 번째 비일관성은 이성의 능력에 대한 그의 입장과 관련되어 있다. 그는 이성의 능력이 진화의 산물이라고 믿으면서 동시에 이성능력은 진화의 맹목성에 저항할 수 있는 능력이라고 믿기도 한다. 세 번째로, 인간의 도덕능력에 대한 평가에 있어서도 그는 모순적인 태도를 노출하고 있다. 이 세 가지 모순들을 고려한다면, 싱어는 인간과 동물 간에는 질적인 차이가 없다는 자신의 주장을 증명하지 못했다는 사실이 분명해진다. 싱어의 이론이 대중들의 호응을 얻고 있음에도 불구하고, 필자는 그의 동물해방론의 이론적 기초가 꽤나 허약하다고 생각한다. 필자가 싱어 이론의 약점을 드러내는 이유는 인간이 동물을 무자비하게 다루는 관행으로 로 되돌아가기 위함이 아니라, 동물복지의 미명하에서 인간의 존엄성을 파괴하는 것이 잘못임을 보이기 위함이다.