• Proceedings of the Korean Information Science Society Conference
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• 2001.10c
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• pp.856-858
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• 2001

분산 파일 시스템에서 파일을 복제하는 목적의 하나는 파일의 가용성을 높이는 것이다 서버들로 이루어진 시스템에서 가용도 문제는 주로 오류 상황이 대상이다 반면에 데스크탑으로 구성된 경우 각각이 상대적으로 가용도가 낮고 그 편차도 커서 파일의 가용도를 최적화 하도록 복제본을 저장하는 것이 기본적인 문제가 된다. 파일 단위 복제 기법에서는 파일 수가 참여 시스템 수에 따라 기하급수적으로 증가하고 파일 배치 때마다 가용도 최적화를 수행해야 하는 문제가 있다. 본 논문에서는 저장 공간 단위 복제 기법을 제안한다. 데스크탑 시스템의 저 장롱간을 고정 크기의 페이지들로 나누고 이들을 조합해서 일정한 가용도를 가지는 페이지 그룹을 형성한다. 파일들은 이 페이지 그룹에 저장된다. 페이지의 개수가 파일 수가 아닌 시스템 수에 의존하고, 파일 배치 시점과 무관하게 페이지 그룹을 만들 수 있는 장점이 있다. 최종 가용도를 높이고 연산 시간을 줄이기 위해 ILS(Iterated Local Search )방법을 이용만 탐색을 수행한다.

• Journal of the Korea Safety Management & Science
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• v.10 no.3
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• pp.63-71
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• 2008

This study was conducted with respect to the causal factors revealed through the investigation of the recent airlines aircraft crash accident which occurred while aircraft was on the climb-out or on the final approach. This study also highlighted the importance of flight deviation and exceedance occurrences in consideration of Flight Operational Quality Assurance Program(FOQA). Twenty airline pilots participated in the flight experiment to perform ten(10) sets of simulated approaches and landings. As a result, Twelve(12) kinds of deviation events were discovered. In this respect, The FOQA program must be fully implemented to prevent any flight safety incident under the auspices of the Korea domestic aviation community as well.

• Wind and Structures
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• v.7 no.3
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• pp.187-202
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• 2004

Wind tunnel experiments are often performed for the identification of aeroelastic parameters known as flutter derivatives that are necessary for the prediction of flutter instability for flexible structures. Experimental determination of all the eighteen flutter derivatives for a section model facilitates complete understanding of the physical mechanism of flutter. However, work in the field of identifying all the eighteen flutter derivatives using section models with all three degree-of-freedom (DOF) has been limited. In the current paper, all eighteen flutter derivatives for a streamlined bridge deck and an airfoil section model were identified by using a new system identification technique, namely, Iterative Least Squares (ILS) approach. Flutter derivatives of the current bridge and the Tsurumi bridge are compared. Flutter derivatives related to the lateral DOF have been emphasized. Pseudo-steady theory for predicting some of the flutter derivatives is verified by comparing with experimental data. The three-DOF suspension system and the electromagnetic system for providing the initial conditions for free-vibration of the section model are also discussed.

• Asia-Pacific Journal of Business
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• v.3 no.1
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• pp.1-9
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• 2012

The Index of Learning Styles (ILS) instrument based on the Felder-Silverman Learning Style Model was used to determine distribution of learning styles of 125 South Korean business students enrolled in a South Korean institution of higher education. Results show that greater proportion of South Korean business students surveyed in this study prefer sensing over intuitive, visual over verbal, reflective over active, and global over sequential learning styles. The majority of business students have a balanced learning style in all four dimensions of the Felder-Silverman model. Among the students that do not have a balanced learning style, students with sensing, visual, reflective, and global learning styles dominate. Gender difference in learning style preference was not statistically significant for any of the four dimensions.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.50.6-50
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• 2001

This paper deals with a design of nonlinear glide slope capture logic using dynamic model inversion in singular perturbation, which is applicable to the autolanding in ILS. Aircraft dynamics are separated into the fast time-scale variables, related with the inner-loop design, and the slow time-scale variables, related with the outer-loop design. It is assumed that the aircraft starts landing at 1000ft of altitude, -2.5deg of flight path angle, and 250ft/sec of velocity. In the outer-loop design, commands of altitude and velocity are selected and thereby the pseudo-controls of power level and pitch rate are determined. Also the elevator input to the aircraft is determined in the inner-loop design. The final design is evaluated in 6 DOF simulation model of the associated aircraft, in which the actuator models are not included. The results show the satisfactory autolanding ...

• Atmosphere
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• v.23 no.4
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• pp.513-517
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• 2013

In this study, it is first intended to simulate the vertical profile of atmospheric flow in a short wind tunnel. In order to accomplish it, proper devices are designed properly to reduce freestream flow momentum and it is confirmed from the measured velocity profile using hot-wire anemometer that momentum flux of the tunnel free stream can be reduced and desired atmospheric boundary can be created. Second, experiments are performed to identify influences of a surrounding structure measuring correct wind velocity by an anemometer, which are located nearby due to area limitation in actual airport and correction factors are proposed from experimental results. One of findings is that in order to limit the velocity attenuation due to a nearby structure under 10%, wind velocity measuring equipment should be installed at least 6 times of the structure height away from the structure of concern.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.4
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• pp.468-476
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• 2018

The Systems Engineering method is increasingly recognized as a central in the Acquisition of Weapon Systems in South Korea. Because of these trends, issues concerned with improving weapon system design are increasingly raised. This paper presents a development of Operational Mode Summary/Mission Profile (OMS/MP) in terms of Weapon Systems Acquisition for application to Systems Engineering method. For a systematic approach, a precise concept of OMS/MP is derived by analyzing the concept of conventional OMS/MP. This paper reviews the results of a series of previously reported examples aiming to develop the OMS/MP of a weapon system. Based on this, the limitations of the conventional OSM/MP applications are investigated. And these limitations can be resolved by the Fundamentals of Systems Engineering. Finally, the OMS/MP framework based on the Fundamentals of Systems Engineering has been proposed and is successfully implemented for the Harbor Underwater Surveillance System.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.19-19
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• 1992

해를 거듭할수록 증가추세에 있는 악성종양은 우리나라의 3대 사망원인 질환의 하나이다. 그러나 현재 암의 화학적 치료법은 40여종의 암치료제가 주종을 이루고 있으나 그 효과면에서 한계점에 도달하고 있어 식물추출물, 해양식물, 미생물 등으로부터 얻어지는 천연물 성분에서 강력하고 부작용이 적은 항암제를 발굴하기 위한 연구가 국내외에서 많이 수행되고 있다. 본 연구는 파푸아뉴기니아산 열대식물 13과 23종의 항암작용을 검색할 목적으로 실시하였는데, 실험동물은 ICR계의 암컷생쥐를 이용하였으며 Sarcoma 180 동물복수암세포에 대한 열대 식물 엑스 투여에 의한 수명 연장 효과를 측정함으로써 항암작용의 지표로 삼았다. 항암작용의 지표는 ILS(Increased Life Span)를 사용하였으며 ILS가 20％이상인 것을 항암성이 있는 것으로 간주하였다. 실험의 결과 Apocynaceae에 속하는 Plumiera rubra의 줄기껍질 및 잎 추출물 Leguminosae과의 Pterocarpus indicus의 잎 추출물과, 같은 과의 Derris trifoliata, Moraceae과의 Artocarpus altilis의 뿌리 및 줄기 껍질, 잎 추출물과 Sterculiaceae과의 Kleinhovia hospita의 잎 추출물, Verbenaceae과의 Vitex trifolia의 5과 5종 8시료가 의의있는 항암작용이 있는 것으로 나타났다.

• The Korean Journal of Quaternary Research
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• v.7 no.1
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• pp.103-111
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• 1993

Apres le Perigordien ancien, les proportions de l'outillage archaique du Prerigordien decroissent progressivement au fur et a mesure que les industries perigordiennes se developpent. Dans le Perigordien superieur ( couche Ⅵ du Flageolet I ) les outils archaiques sont beaucoup moins frequents que dans le Perigordien ancien, mais ils perdurent encore en proportion notable et leur indice atteint 31,23. Par la suite, dans le Perigordien superieur evolue la frequence de l'outillage archaique est naturellement la plus faible pour le Perigordien et 1'indice moyen d'outils archaiques y descend a 17,99.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.479-482
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• 2003

Radiosensitizing and antitumor effects of hot water extract derived from the seed of Benincasae hispida were investigated. The extract showed maximum survival rate of 21% at 0.1 g/kg against L1210 cells implanted in BDF1 mice. Radiosensitivity of human tumor cell line was evaluated through sulforhodamine assay. Inhibition rate of SK-OV-3 cells after 5 Gy radiation by Benincasae hispida seed extract at 2 mg/mL was 86%.