• Journal of the KSME
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• v.33 no.10
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• pp.902-911
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• 1993

반능동 현가 시스템의 장점은 능동 및 수동 현가 시스템의 장점을 모두 갖고 있다는 것이다. 즉, 반능동 시스템은 수동 현가장치에 비해 우수한 성능을 제공하면서 대형 액츄에이터나 큰 동력 원을 필요로 하지 않는다. 지금까지는 승차감 및 조향성능을 향상시키기 위한 능동 및 반능동 현가시스템에 관한 연구가 많이 이루어졌으나, 능동 또는 반능동 현가시스템을 이용하여 대형 차량의 주행 안정성을 향상시키고, 대형차량에 의해 주로 발생하는 도로의 파손을 줄이면서 차 량의 수송능력을 향상시키는 연구는 최근에 유럽과 미국의 대형트럭 제조업체와 정부 주도로 활발하게 진행되고 있다. 그러므로 반능동 현가시스템에 의한 대형 트럭의 성능 향상 가능성 및 연구 개발도 승용차용 능동 및 반능동 현가시스템과 함께 앞으로의 주 연구 과제이다. 이글에 서는 우선 가변 댐퍼 및 반능동 현가시스템의 기본 원리를 설명하고, 반능동 현가시스템의 Bilinear Model, 제어방법에 대하여 언급한 후, 컴퓨터 모의 실험결과를 통하여 반능동 현가시 스템에 의한 차량의 동적 성능 향상을 두 가지 측면, 즉, 승용차와 대형트럭의 측면에서 언급될 것이다.

• The Journal of the Korea Contents Association
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• v.16 no.6
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• pp.802-813
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• 2016

This study examined the Japanese and Chinese journalist's views on anti-Korean wave, who are the public and authoritative discourse producers in Japan and China, respectively. In so doing, the study aims to understand the ways in which the phenomena of anti-Korean wave take place and are diffused. According to the findings, anti-Korean wave in north-east Asia is affected by anti-Korea sentiments that have been induced from historical and political relations as well as cultural conflicts. In specific, the anti-Korea sentiments found in both Japan and China are geopolitical particularity and historical relations function to frame their cultural receptions of Korean pop culture. In other words, the phenomena of anti-Korean wave in both countries do not stem directly from local audiences' either discontents or apathy on Korean pop contents. However, while Japanese anti-Korean wave seems to be mere expressions of anti-Korea sentiments, Chinese sentiments of anti-Korean wave are triggered and transferred by, or articulated with their anti-Korea sentiments.

• Applied Chemistry for Engineering
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• v.10 no.8
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• pp.1180-1185
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• 1999

Modispersed silica fine particles were produced from the hydrolysis of $Si(OC_2H_5)_4$ by using batch-semibatch mixed systems. Four types of mixed process, i.e., batch-batch, batch-semibatch, semibatch-batch, semibatch-semibatch, were used in order to measure mean particle size, particle size distribution, yield, and packing density. As a result of the test, silica particles prepared by semibatch-semibatch process were larger than those prodeced from any other systems in particle size and yield. On the other hand, silica particles prepared by batch-semibatch process were better than those produced from any other systems in particle size distribution and packing density. Especially, it was found that particle size of $SiO_2$ prepared by semibatch-batch process decreased with increasing the reaction time. Therefore, batch-semibatch process was a successful method for controlling the size, i.e., a narrow distribution of a particle size which ranges to several microns.

• Journal of Elementary Mathematics Education in Korea
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• v.6 no.1
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• pp.77-96
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• 2002

This study aims at checking up influences imposed on mathematics learning abilities in communication teaching through small group leaning for the sixth grade pupils of elementary schools. Results obtained through the study are as follow: The communication teaching through small group cooperative learning showed an affirmative reaction in terms of mathematics learning achievement degree and mathematical tendency. However, the pupils of the lower group showed a meager effect in terms of mathematics learning achievement degree. It means that such an effect is required to a sustained teaching for a long time by teachers.

• Journal of Korean Institute of Fire Investigation
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• v.6 no.1
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• pp.67-71
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• 2005

화재 발생에 따른 화재조사 시 배전반이나 분전반의 완전 소락에 따른 전기화재 원인규명의 기본적이고도 중요한 증거 소멸로 원인불명 율이 점차 높아가고 있는 실정이다. 공장이나 창고에서 전기화재를 가장한 수 배전반 화재를 시도할 경우 그 증거를 찾기 어렵다. 또한, 수 배전반이 위치한 곳에 사람이 상주하지 않는 곳이 많으며 초기 소화가 원활히 이루어지지 않을 경우 막대한 재산 피해와 통신의 대혼란을 가져올 소지가 다분히 존재하고 있다. 따라서, 수 배전반 및 분전반의 화재로부터 보호하기 위해서는 신뢰성과 안전성이 확보된 자동소화 시스템의 도입이 필요하다.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.552-555
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• 2000

본 연구에서는 수직순환식 기계식입체주차설비용 주 구동전도기인 유도전동기를 제어할 수 있는 인버터와 컨버터를 일체화한 165kVA급 인버터장치와 통합 시퀀스제어 및 보조 장치용 전도기 제어를 위한 목적으로 PLC형 제어반을 구성하였고 사용자와의 MMI개선을 위한 목적으로 Pro-Face 터치스크린을 적용한 운전반을 구성하였다 주 구동장치의 제어를 위한 인버터반은 인버터부와 컨버터부 및 입출력부로 구성하였으며 인버터반 내의 제어장치는 병렬통신처리를 하였고 인버터반과 PLC형 제어반 사이는 RS-232C방식 통신체계를 갖추도록 하였다 터치스크린형 운전반과 PLC형 제어반은 RS-422 통신기능을 갖는 C-Net 카드를 적용 하였으며 실험은 55kW급 유도전동기를 대상으로 하였다.

• Korean journal of applied entomology
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• v.57 no.1
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• pp.1-5
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• 2018

Tachinus (Tachinus) javanus Cameron is identified for the first time in the Korean Peninsula. Description, illustrations of habitus and diagnostic characters, and a key to the known species of Korean Tachinus Gravenhorst are provided. Tachinus (Tachinus) yezoensis Li is redescribed with male characteristics.

• Review of KIISC
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• v.14 no.2
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• pp.23-37
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• 2004

지금까지 IETF에서 공개키 기반구조에 대한 표준화 작업은 PKIX 작업반$^{[5]}$에서 주로 수행되었지만, 최근 들어 4개의 새로운 작업반이 만들어졌다. 새로 생성된 작업반은 IPSEC을 위한 공개키 기반구조 표준을 개발하는 PK14IPSEC(PKI for IPSEC) 작업반$^{[36]}$, 장기간 서명 데이터의 존재와 디지털 서명된 데이터의 타당성과 존재성을 증명하기 위한 표준을 개발하고 있는 LTANS(Long-Term Archive and Notary Service) 작업반$^{[32]}$, 공개키/개인키와 인증서 등으로 구성되는 크리덴셜(Credential)을 획득하기 위한 등록 과정에 대한 모델을 표준화하기 위한 ENROLL(Credential and Provisioning) 작업반$^{[41]}$, 그리고 안전하게 크리덴셜을 한 장치에서 다른 장치로 안전하게 전달하기 위한 표준을 개발하는 SACRED(Securely available Credentials) 작업반$^{[28]}$ 등이다. 본 논문에서는 IETF 보안영역에서 수행되고 있는 공개키 기반구조에 바탕을 둔 여러 작업반에서 최근 수행중인 표준화 동향을 분석한다.

• Journal of Gifted/Talented Education
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• v.23 no.6
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• pp.1019-1034
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• 2013

The purpose of this study is to investigate the characteristics of convergence gifted students through the their perception of the differences about scientists between Science class and Convergence class in gifted science education center. Consequently, this article reports that there are differences in the perception about scientists was distinction between applicants of Convergence and Science class. Science class applicants mainly recognized scientists as pure scientists, but Convergence class applicants recognized scientist were including mathematician, artist, architect, etc. Also Convergence class applicants thought that affective domain including 'effort', 'patience', 'interest' was more important that Science class applicants. On the other hand, when they described the scientists, Science class applicants knew their achievements as scientists more specifically than Convergence class. And to conclude, the characteristics were different between Convergence and Science class applicants in gifted science education center. Based on the result of this study, this paper suggests the following: Firstly, conceptual study is urgent about convergence gifted students in their definition and characteristics. Secondly, information regarding the criteria to select student for convergence class in gifted science education center. Finally, when teaching convergence gifted students, attention should be paid to their characteristics such affective domain.

• Journal of the Korean Wood Science and Technology
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• v.43 no.3
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• pp.381-389
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• 2015

In this study, the effects of moisture content and particles size of ground particles of torrefied larch chips on the pelletizing process were investigated depending on torrefaction conditions ($220^{\circ}C$-50 min, $250^{\circ}C$-50 min, $250^{\circ}C$-120 min). The moisture content in the torrefied chip decreased to 0.69~1.75%, while ash content and calorific value increased compared to untreated chip. In addition, weight loss significantly increased during torrefaction due to hemicellulose degradation. The carbon content in torrefied larch chip increased compare to untreated larch chip, while the hydrogen and oxygen contents decreased. The lignin and glucan contents in torrefied larch chip increased with increasing severity of the torrefaction condition, while hemicellulose decreased. In the particle size distribution of ground particles of torrefied larch chip, larch torrefied at severe conditions was found to produce smaller particles (~1 mm) than that of the larch torrefied at mild conditions. Macropore (over $500{\AA}$) in the torrefied particle was produced during torrefaction. During the pelletizing using ground particles of torrefied larch chip, the pressure needed in pelletizing decreased and pellet length increased with increasing moisture content, regardless of the particle size.