• 제목/요약/키워드: shin-huh

검색결과 522건 처리시간 0.043초

Optimum Design of Process Conditions to Minimize Residual Stress and Birefringence in Injection -Molded Parts

  • Sejin Han;Huh, Yong-Jeong;Kang, Shin-il
    • International Journal of Precision Engineering and Manufacturing
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    • 제2권2호
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    • pp.17-25
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    • 2001
  • In this paper, a theoretical study has been made to reduce the residual stress and birefringence in the injection-molded parts. An optimization program has been used to minimize the residual stresses and birefringence calculated from a simulation program. The thermally induced stress has been calculated using a linear viscoelasticity model. The flow stress and birefringence has been calculated using the Leonov's viscoelasticity model. This has been applied to the injection molding of a circular disc and a plate. the optimization has been done either by changing process variables while maintaining the mold temperature constant or by varying the mold-wall temperature with time. This study shows the significant reduction in residual stress and birefringence is possible through the optimization of processing conditions.

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합성 펩타이드 유도체들의 황산화능 (Study of Antioxidant Activities of Synthetic Peptide Analogues)

  • 구자석;허남원;강신원
    • 한국응용과학기술학회지
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    • 제4권2호
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    • pp.19-23
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    • 1987
  • The addition of dipeptides and 1,2-bis (aminoacyl) hydrazine derivatives a level of 250 ppm to corn oil resulted in the retardation of the oxidaitive deterioration of the oil when it was stored in the oven at $70^{\circ}C$ during 5 days. Their antioxidant activities were investigated by UV absorbance of the corn oil at the wavelength of 234nm. 1,2-bis (aminoacyl) hydrazine derivatives showed higher antioxidant activity than normal dipeptides. Dipeptides containing phenyl ring with which is conjugable a-carbon radical showed antioxidant activity.

ET-1 RIA and Immunocytochemistry on EAE-induced lewis rat

  • Bongsu Kang;Park, Youngshim;Inhoi Huh;Taekyun Shin
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1996년도 춘계학술대회
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    • pp.193-193
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    • 1996
  • Endothelin-1, which is a peptide originally isolated from cultured porcine aortic cell, has been found to play a crucial role in potentiating the vasoconstriction mitogenesis, and chemotaxis. In the present study, we examined the level of endothelin-1 in the brain, spinal cord and blood from rat with experimental allergic encephalomyelitis(EAE). At the peak stage of EAE(grade 3), endothelin-1 level in the spinal cord of rat with EAE increased two folds as compared with that of sham-treated rats, and subsequently decreased to the level of control at the recovery stage. In the endothelin-1 immunocytochemistry, endothelin-1 immunopositive cells and ED-1, macrophage marker immunopositive cells observed in the spinal cord of peak stage(grade 3). These Findings suggest that endothelin-1 play the important role in progression of EAE.

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S/MIME을 사용한 양단간 보안기능 제공하는 SIP 시그널링 기법 구현 (Implementation of End­to­End Secure SIP Signaling using S/MIME)

  • 현욱;박선옥;허미영;강신각
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2003년도 가을 학술발표논문집 Vol.30 No.2 (3)
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    • pp.181-183
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    • 2003
  • RFC3261에 정의된 SIP 프로토콜에는 보안 및 인증과정을 위한 동작 메커니즘을 정의하고 있다. 서비스 제공을 위한 인증이나 권한 점검을 위해서는 HTTP Digest방식이 가장 일반적이고 검증된 방식이긴 하나, 보안의 측면을 보았을 때 안전하지는 않으며, 서버와 단말 또는 단말간의 인증에만 사용되므로 완벽한 형태의 보안을 제공한다고 볼 수 없다. 이러한 보안상의 무결성, 안정성에 있어서의 기능을 충족시키기 위해 RFC3261의 후반부에서는 TLS와 S/MIME의 지원을 권장하고 있으며 현재 IETF에서 진행중인 draft나 각종 RFC에서도 보안 문제를 해결하기 위해 S/MIME과 TLS를 필요한 사항으로 정의하고 있다. 본 고에서는 S/MIME기능을 SIP프로토콜에 적용하기 위해 필요한 사항 등을 구현관점에서 바라볼 것이며, 이를 위해 해당 기능의 구현을 위해 사용된 구현구조 및 관련 API의 설명을 통해 접근하고자 한다.

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LDD MOSFET의 유효 채널길이 측정법에 관한 연구 (A Method for Effective Channel Length Extraction on Lightly Doped Drain MOSFET's)

  • 박근영;허윤종;이계신;성영권
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1992년도 하계학술대회 논문집 B
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    • pp.825-828
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    • 1992
  • In this paper, a Hybrid method for an effective channel length($L_{eff}$) on lightly doped drain(LDD) MOSFET's is proposed. In order to investigate the difference of the gate bias and substrate bias defendence of the $L_{eff}$ among various LDD structures, the $L_{eff}$ of the LDD's are extensively examined using simulations and measurement. one group is proposed for conventional MOSFET and the other group Is proposed for LDD MOSFET. It is shown that the $V_{bs}$-dependence of the n-region is different from $V_{gs}$-dependence of it.

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패랭이꽃 N-Butanol 추출물의 자궁수축작용에 관한 연구 (Studies on the Uterotonic Action of N-Butanol Extracts from Dianthi Herba)

  • 허근;류항묵;이상일;박종민;송재웅;신억섭
    • 생약학회지
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    • 제19권4호
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    • pp.256-261
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    • 1988
  • The present studies were investigated to find out the uterus contractive components and action mechanism of contractive components. We observed that the contractive components of Dianthi Herba were extracted with methanol and dissolved in butanol. The butanol extracts of Dianthi Herba increased uterus contractility, and fraction 2 obtained from butanol extract was more powerful than other fractions. This action was not blocked by atropine, papaverine, prazosin, propranolol, chlorpheniramine, methysergide and diltiazem in vitro.

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역(逆)접근 방법에 의한 각막의 물성치 연구와 엑시머 레이저 수술에의 응용 (Inverse Approach to Study the Mechanical Properties of the Human Cornea and its Application to the Excimer Laser Surgery)

  • 허준영;신정욱;한근조
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1994년도 춘계학술대회
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    • pp.127-130
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    • 1994
  • This study is focused on investigating the mechanical properties of the human cornea and its shape through the inverse nonlinear finite element approach using the clinical and experimental data. The results of the inverse approach were used to construct the finite element model of the photorefractive excimer laser surgery for the myopia patients. The results of the finite element model were compared with those of the current clinical experiences and showed good agreements. Finally this study came to the conclusion that the finite element method has potential of the application to the medicine.

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An Investigation into Research Productivity in the Journal of Consumer Behavior

  • Shin, Dong-Jin;Huh, Mooyul
    • 유통과학연구
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    • 제13권2호
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    • pp.45-53
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    • 2015
  • Purpose - This study strives to discern trends in research productivity in the Journal of Consumer Behavior. It will identify prolific authors and institutions in articles over ten years (2004-2013). Research design, data, and methodology - The Journal of Consumer Behavior was chosen and articles over ten years were analyzed. Research productivity was determined by categorizing the data into four themes: number of authors per article, author affiliated institutions, a list of prolific authors over a ten-year period, and author-affiliated countries. Results - Authors have a propensity to collaborate on a research paper, yielding a high frequency of articles with two or three authors in a single publication. In addition, author and institution productivity was highest in North America and Europe. Conclusions - The research productivity of the Journal of Consumer Behavior is unprecedented. The trends and insights from this study will allow academics in the area of consumer behavior to observe leading authors and institutions. Moreover, speculations about the leading countries and institutions, not to mention top prolific authors in consumer behavior, will be elucidated in this study.

A Cost-efficient IPTV Strategy of Replica Placement for $3^{rd}$ Party Content Service

  • Diaz, Maria Elizabeth Aldana;Shin, Young-Rok;Huh, Eui-Nam
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2011년도 한국컴퓨터종합학술대회논문집 Vol.38 No.1(A)
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    • pp.391-394
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    • 2011
  • 3rd party content service is a consumer-based wide selection of contents in which IPTV provider believes will enhance the service considerably extending the variety of contents to finally provide a personalized service. Therefore, the combination of 3rd party content services and the IPTV infrastructure creates a good revenue opportunity but they need to be created. IPTV offers to create personalized channels to distribute 3rd party content service. However, the cost of $3^{rd}$ party content delivery is high when the service is provided from a faraway server. IPTV provider requires an effective strategy of replica placement to minimize the cost without a tradeoff on the performance. We propose a cluster-based strategy of replica placement to find the right balance between cost and performance. The results demonstrate the achievement of an outstanding delivery time and low cost.

지식 추상화와 의미 거리 접근법을 통합한 질의 완화 방법론 (Relaxing Queries by Combining Knowledge Abstraction and Semantic Distance Approach)

  • 신명근;박성혁;이우기;허순영
    • 한국경영과학회지
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    • 제32권1호
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    • pp.125-136
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    • 2007
  • The study on query relaxation which provides approximate answers has received attention. In recent years, some arguments have been made that semantic relationships are useful to present the relationships among data values and calculating the semantic distance between two data values can be used as a quantitative measure to express relative distance. The aim of this article is a hierarchical metricized knowledge abstraction (HiMKA) with an emphasis on combining data abstraction hierarchy and distance measure among data values. We propose the operations and the query relaxation algorithm appropriate to the HiMKA. With various experiments and comparison with other method, we show that the HiMKA is very useful for the quantified approximate query answering and our result is to offer a new methodological framework for query relaxation.