• Electric Engineers Magazine
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• v.222 no.2
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• pp.21-29
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• 2001

경보시스템에서 대다수의 출력 변환기는 전기 에너지를 음향 에너지로 전환시키지만 때때로 출력 변환기는 전기 신호를 광에너지로 전환시킬 것이다. 경보 시스템의 출력 음향 장치는 다음의 두기능중 하나 또는 모두를 행하기 위한 것이다.

• Journal of the Korean hospital association
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• v.36 no.1 s.305
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• pp.35-42
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• 2007

• The Science & Technology
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• s.510
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• pp.18-21
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• 2011

• Food Industry And Nutrition
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• v.2 no.1
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• pp.7-9
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• 1997

내열설 미생물, Thermus caldophilus CK24에 대한 탄수화물 생합성을 연구하는 과정에서 다양한 탄수화물 관련효소를 탐색하고 그레 대한 생화학적 및 분자생물학적 연구를 수행하고 있다. 일차로 내열성 미생물내 1) 당핵산염 합성효소와 당전이 효소, 2) 탄수화물 대사효소. 3)탄수화물 분해 및 전환효소의 존재를 HPLC/Bio-LC분석을 통하여 확인하고 이들에 대한 연구를 진행하고 있다. 본 연구발표에서는 포도당을 과당으로 전환하는 이성화효소(xylose isomerase), 그리고 맥아당을 트레할로스로 전환하는 트레할로스 합성효소(trehalose synthase)를 소개하고저 한다. 이성화효소는 이미 산업적 과당 생산에서 대규모적으로 사용되고 있는 식품산업효소이다. 본 연구에서는 Thermus caldophilus GK24, Thermus thermophilus HB8, Thermus flavus AT62 3종의 내열성 미생물에 대한 이성화효소 유전자를 클로닝 하고, 각 재조합하고 이성화효소를 대량생산하였다. 이 내열성 이성화효소는 최적 반응 온도가 8$0^{\circ}C$이고, 포도당을 과당으로 전환하는 수유른 55%이었다. 이러한 과당전환률은 이미 산업적으로 사용되고 있는 이성화효소의 과당전환률(43%)보다 훨씬 높은 것으로 과당 생산공정의 단순화의 생산성 향상에 결정적인 요인이라 할 수 있다. 한편 본 이성화효소의 산업적 특성을 증대하기 위하여 구조-기능관계 연구를 착수하였다. 우선 내열성 이산화 효소의 입체 구조를 결정하였고, 구조조정에 따른 기능적 특성을 조사하기 위하여 특정 위치의 선택적 변이 연구를 진행하고 있다. 끝으로 포도당 전이 효소를 추적하던 과정에서 맥아당을 트레할로스로 전환하는 새로운 효소를 Thermus caldo-philus GK24에서 발견하였다. 그 트레할로스 합성효소는 분자량이 약 110kDa이고 최적 반응온도가 75$^{\circ}C$이면, 조효소없이 맥아당을 트레할로스로 80%이상 전환해 주는 가역효소이었다. 본 연구에서는 효소반응의 조건과 특성을 조사하였고, 효소 아미노-밀단의 서열결정정보를 통하여 효소의 유전자를 클로닝 하고 그 유전자의 구조와 발현연구를 진행하고 있다.

• Journal of Life Science
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• v.18 no.3
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• pp.304-310
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• 2008

Heat shock protein 70 (HSP70) is known as molecular chaperone, the fundamental protein participating in various processes, from nascent protein synthesis to protection of proteins during abiotic stresses and developmental programs. However, their biological functions in plants are not yet well known. Here, NtHSP70-1 (AY372069), HSP70 of Nicotiana tabacum induced by heat stress was investigated. To analyze the protective role of NtHSP70-1, transgenic tobacco plants, which constitutively overexpressed NtHSP70-1 as well as contained either the vector alone or having NtHSP70-1 in the antisense orientation, were constructed. The altered NtHSP70-1 levels in plants were confirmed by western blotting and transgenic sense lines exhibited tolerance to heat stress. Seedlings with the constitutively expressed NtHSP70-1 grew as green or healthy plants after heat stress. In contrast, transgenic vector or antisense lines exhibited yellowing of leaves or some delay in growth, which finally led to death. Evaluation of chlorophyll contents of heat-shocked transgenic tobacco seedlings indicated that NtHSP70-1 contributes to thermotolerance by preventing chlorophyll synthesis in plants.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.1
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• pp.83-93
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• 2017

Recently, the development of multi-purpose tunnel that has functions of roads and waterways has been attention for efficient utilization of underground space. However, there is no study on the multi-functional tunnels behavior for the convert of iterative function and change of water pressure. In this study, the vulnerable section was analyzed due to repeated functional change. A basic review was implemented for the operation of the multi-purpose double-deck tunnel. Also, the vulnerable section for convert of iterative function of multi-functional tunnel has been analyzed by simulation. Management of multi-functional tunnel should considered in various analyzed and some problems. The criteria for management of multi-functional tunnels is proposed.

• Proceedings of the Korea Contents Association Conference
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• 2006.11a
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• pp.26-30
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• 2006

Internet phone service is a new service technology that provides voice call services through Internet not through the pre-existing PSTN. It enables a cheap voice call service regardless of distance. We may expect that the Internet phone service may substitute for the voice call service through the PSTN, but not in a short period. There are several problems to be solved for this transition, such as, voice call quality, numbering scheme, billing, standardization, and support of several functions. In this paper, we provided and designed a UA (User Agent) that can support functions regarding voice call, such as call forwarding, auto-connection, call rejection and restriction of individual call, using SIP (Session Initiation Protocol) which is proposed by SIP-Working Group as the standard Internet phone service management protocol.

• Journal of the Korean Society for Railway
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• v.18 no.4
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• pp.335-343
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• 2015

The role of the turnouts installed on the points of railway branches and intersections is to safely switch the directions of trains. In case of abnormal forces applied to the turnouts due to extreme operating conditions, it is difficult in the current system to conduct accurate diagnosis and measuring. Moreover, the existing measurement devices for turnout switching power are mostly based on foreign technologies, which provide only limited information on the switching power; this information is insufficient for effective monitoring and maintenance. In this paper, through an analysis of the characteristics of the switching and locking function, the problems in turnout power measurements of current electrical point machines in Korea are examined. And based on the results, a new sensor-based method for measuring switching power is proposed.

• 어항어장
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• s.37
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• pp.13-18
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• 1996

• Korea Petroleum Association Journal
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• s.303
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• pp.24-27
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• 2017