• Proceedings of the Korea Information Processing Society Conference
• /
• 2002.04b
• /
• pp.1139-1142
• /
• 2002

우리 나라의 건설산업은 건설시장 개방으로 외국기업과의 경쟁체제 돌입이 불가피하고, 건설정책과 각종 행정규제의 급변으로 대응전략 수립이 불가피하다. 또한, 건설정보의 지식관리체제의 부재와 건설지식관리정보시스템의 미구축, 그리고 정보 공유와 공공정보 공개 마인드의 미성숙으로 인하여 적극적인 대처가 불가능한 실정이다. 따라서 본 논문에서는 건설업체, 설계사무소, 감리업체 등이 안고 있는 제반 현황을 고찰하여 건설지식관리정보시스템 구현방안을 제시 이를 건설지식관리정보시스템에 적용하여 국내 건설분야 건설지식 맵 활용 실태를 파악하고, 해외 각국에서 지식관리의 활용관련 자료를 분석하여 국제기준 및 국내 건설환경에 적합한 기능규격 및 시스템 개발 건설업체에 적용하였다

• 대한한약신문
• /
• s.121
• /
• pp.1-8
• /
• 2007

국세청, 7월부터 현금거래 신고.확인제 시행/수입한약재 정밀검사품목 90품목 추가/제63차 한약수급조절위원회 회의/서울약령시 한의약문화축제 성황리 폐막/'녹용없는 녹용탕' 유명 프랜차이즈 한의원 '눈속임'/'한약재 포제품' 제법.규격 표준화 추진/세명대, '한방바이오산업 임상지원센터' 설치사업 확정/안궁우황환 사건 관련 한조약 VS 한의협 주장 엇갈려/국내 우수한약제품 해외시장 진출 본격화/"맥문동.시호.황금.백수오 개방 유예"/희귀난치성질환 정보 이용 접근 더 쉬워져/커피, 간암 예방 효과 있어 하루 2잔 이상, 간암 위험 43% 감소/고려 홍삼 중국 진출 '청신호'/아토피 피부염 한약치료 임상시험자 모집/한의약 R&D투자, 과기 전체의 0.13%/생약협 '함양 하고초 마을 약초기행' 실시/중국, 중의약 규범 국제표준화 추진/동의의료원, 양한방협진 강화/'양.한방 협진의 미래 지향적 접근' 세미나/비증 이야기/명칭이 비슷하여 감별하기 어려운 한약재/지부탐방-지부장에게 듣는다/우리 약초를 찾아서-황기

• Journal of Digital Convergence
• /
• v.14 no.1
• /
• pp.181-187
• /
• 2016

Typical Retro-reflectors installed on road have problems such as limiting a driver's visibility at night when it is foggy or rainy. On the other hand, LED illuminated studs, called cat's eye system, extends a driver's visibility under these conditions. In this paper, we present a design of the LED cat's eye system using solar energy that can sustain vehicles with about 30-ton weight and is compliant with the IP68 code for water proof as IEC standard 60529. In addition, we propose a scheme of designing a LED driving circuit consuming low power to take into accounts cold weather or rainy season with limited sunlight. This LED cat's eye studs is currently installed and used on expressway and bike route nationally as well as overseas.

• Proceedings of the KIEE Conference
• /
• 2000.07d
• /
• pp.3151-3153
• /
• 2000

현재 국내에서 사용되는 교통신호등용 전구는 전량 해외에서 수입하는 백열전구로써 발열에 의한 낮은 발광 효율과 짧은 수명으로. 전력의 과소비와 과중한 전력요금 부담. 잦은 유지보수로 관리비용의 증가와 교통환경 악화의 원인이 되고 있으며, 국가적으로는 귀중한 에너지의 낭비, 첨두부하 증가에 따른 전력수요관리의 어려움, 발전용 화석연료 사용증가에 따른 환경오염 유발 등의 문제가 발생하고 있다. 그러나 $8{\sim}12$인치의 원형(또는 사각) PCB 기판에 수백개의 고휘도 LED(반도체 발광 다이오드, Light Emitting Diode)와 구동회로로 구성되는 LED 교통신호등은 발열에 의한 열손실이 거의 없고, 특정 파장대의 단색광을 발광하여 착색렌즈 사용에 따른 빛손실이 없어 80% 이상의 대폭적인 에너지 절약이 가능하며. 또한 긴 수명으로 유지보수비용의 절감 및 교통환경개선 효과가 크게 기대되어 미국, 일본 등 고휘도 LEB 기술 선진국을 중심으로 경쟁적으로 LED 신호등 기술개발에 심혈을 기울이고 있으며, 일부 시범 보급중에 있다. 교통신호등은 특성상 국민의 안전과 직결된 사안으로 엄격한 규격으로 제한하고 있다. 그러나 LED 신호등은 발광 원리 및 발광 방식이 기존의 전구식과 달라 현재 규정된 시험방법으로 직접 평가가 불가능하다. 따라서 우리나라의 경우 LED 제조 기술은 세계적인 수준이나 LED 신호등에 대한 기술개발 및 보급은 현실적으로 어려운 실정이다. 본 논문에서는 에너지절약형 우리나라 환경 특성에 적합한 LED 교통 신호등의 규격 제정 및 국내 보급환경 구축을 위해 LED 신호등에 대한 시제품의 특성을 장시간의 옥외 시험을 통해 평가하고자 한다.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.11 no.5
• /
• pp.60-71
• /
• 2007

The startup characteristic of liquid propellant rocket engine should be focused on the stable ignition of combustion chamber and gas generator. Also, to lessen the propellants consumption during this period which doesn't contribute to the flight thrust, the engine has to be transferred to the nominal mode quickly. Because of the risk of test, it is impossible to develop all the startup cyclogram or the specifications of engine by test, so the precedent numerical approach is quite necessary. In this study we developed a mathematical model for the startup phenomena in a liquid rocket engine driven by gas generator-turbopump system based on the commercial 1-D flow system analysis program, Flowmaster. Using this program we proposed a methodology to obtain the specifications of turbine starter and the opening time of shutoff valves for the stable startup of the engine. To verify this methodology we qualitatively compared the analysis results to the typical startup curve of the published engine, then found it is quite well matched.

• Journal of Korea Port Economic Association
• /
• v.25 no.3
• /
• pp.1-20
• /
• 2009

A survey to pallet users was conducted in an aspect of the efficiency and benefit. The questionnaire identified the preference about the main variables such as price, size, conformity, material, which are the criteria of the users' choice. staffs in the capital region was selected as respondents and Cluster Analysis and Simulations was carried out with Conjoint Analysis. The result shows that the variables of material and conformity between facilities and products were more important than the variable of size. The respondents prefer the pallets with a various range of products because warehouses should keep a range of products under various condition of temperature. In accordance, the companies that provide a pallet pool service should set up individual marketing strategy by a type of customers so as to maximize the competitiveness in domestic or international markets. Furthermore, supplying standardized pallets should be consistent with the standardization not for individual logistics units, but for whole logistic systems. To achieve this, it requires the compatibility amongst a range of logistics activity participants by their characteristics.

• Journal of Advanced Navigation Technology
• /
• v.22 no.2
• /
• pp.105-110
• /
• 2018

The North Korea nuclear issue is now posing a serious security threat to the Korea and Northeast Asia. Accordingly, the South Korean military is pushing for the introduction of long-range air-to-surface flights and the development of domestic nuclear facilities that can precisely hit North Korea headquarters building and nuclear facility even hundreds of kilometers above the border. In this paper, we removed the cable braid for securing the weight of the missile among several design elements for long-range air-to-surface missile development and estimated and analyzed the resulting performance. The possibility of braid removal was analyzed in terms of crosstalk inside the cable and CS114, RE101 of MIL-STD-461F.

• Journal of the Microelectronics and Packaging Society
• /
• v.14 no.2 s.43
• /
• pp.23-33
• /
• 2007

The growing environmental regulation governs the use of lead by RoHS, WEEE, and then. The electronic industry is moving to replace Pb-bearing solder with Pb-free solder. To use the Pb-free solder, microelectronic industry needs consequently the new reliability appraisal such as the packaging for high temperature process, various mechanical change caused by new solder, and the development of Pb-free sloder for long life of product. The evaluation of solder bar and mechanical properties of joint were performed compared with international standard, and new appraisal standard was established. The solderability and spread ability of Sn-0.7Cu solder material showed up to the standard. Shear test of solder joint using by the solder resulted that the shear strengths after thermal shock or after aging were not much lower than the shear strength of as-soldered and that they were also up to the standard.

• Aerospace Engineering and Technology
• /
• v.13 no.1
• /
• pp.142-152
• /
• 2014

This paper analyzes the conjunction events of Korea satellites by year or kind of satellite using CSM, which is provided by JSpOC. If multiple CSM for single conjunction event are available, consistency analysis is performed using minimum range of CSM. And this paper presents the contact analysis results with space objects if there is a radar system in Korea. The effectiveness of Korea's radar system is analyzed by calculating the access time or frequency with space objects. Furthermore, we investigate the radar systems of other space agencies and find the specific parameter depending on the operating environment. Using this information, we define the requirements of radar system, which is appropriate the Korea.

• Aerospace Engineering and Technology
• /
• v.6 no.1
• /
• pp.165-172
• /
• 2007

A space launch vehicle is a very complex system composed of many kinds of components. It is necessary for even a small piece of components in it to be free of defects, malfunctions and to operate normally for the sake of the mission success. For these reasous, a variety of tests are carried out. Burn-in test is to detect latent material and workmanship defects which occurs early in the components use. Developed countries for the space technology have considered the burn-in test for flight vehicles in the standard test documents and performed it. Referred to the documents, application methods of burn-in test will be considered for the components of domestic space launch vehicles such as KSLV-I in this document.