• Analytical Science and Technology
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• v.25 no.3
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• pp.190-196
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• 2012

The human exposure of lead has usually detected the amount of lead in the whole blood, however, this method has a shortcoming to give the information on the short-term exposure to lead. In that sense, it is desirable to estimates the level of lead in plasma to draw the chronic bio-marker of lead exposure even though it is difficult to measure lead of several ng/L. An inductively coupled plasma-mass spectrometry (ICP-MS) method was developed for determining lead in plasma as the chronic bio-marker of lead of workers. To minimize the contamination of lead from the environment, we constructed class 1,000 clean room and compared the amount of floating dust before and after the operation of the clean room. The limit of detection (LOD) and the limit of quantification (LOQ) of lead in fetal bovine serum were 4.3 ng/L and 12.2 ng/L by NIOSH method (statistical calculation method) and 7.0 ng/L and 22.1 ng/L by signal/noise ratio, respectively. The accuracy was in a range of 92.3-101.3%, and the precision of the assay was less than 4% in the samples spiked in the concentration of 20 ng/L and 2,000 ng/L. The method was simple, reproducible and sensitive enough to permit reliable analysis of lead to the ng/L level in plasma and/or serum. The method was also useful for the biological monitoring of chronic exposure to lead.

• Korea Trade Review
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• v.48 no.2
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• pp.217-243
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• 2023

This study revealed practical implications by analyzing the clauses and disputable issues of the Korea Service Contract. Korea introduced Servcie Contract in the container part since Hanjin Shipping's bankrupcy and distributed the standard form(2019). After that, the standard form was revised during the supply chain crisis(2022). In the standard form, there are clause that require agreement due to conflicting interests of shipper and carrier. Therefore, the main clauses of the standard form were analyzed to derive the practical meaning to the both parties. In addition, in the process of introducing the standard form, the most disputable issues, liquidated damages and minimum quality commitment, were deeply analyzed to explain how shipper and carriers' benefit and loss differ as the clause changes. In conclusion, both parties must set LD at a very reasonable level so that they do not proceed separately with penalty. In addition, 'evenly' is a much more important than quantity for carrier in the establishment of MQC, so extra box option for shipper even during the peak season is needed to accommodate with service contract.

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

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.1B
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• pp.49-55
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• 2002

IMT-2000 mobile system will provide many application services such as mobile internet, wireless electronics commerce applications using air interface with high data rate. These applications require high data integrity, data confidentiality, user authentication, user identity confidentiality and non-repudiation. In this study, we analyze new security threats and air interface traffic performance for IMT-2000 mobile systems. Signal traffic for network access security services requires 0.2kbps~4.5kbps with the conditions of 246~768bits/massage, 0.2~1.0 basic services/sec and the security services of the rate 0.2~1.0 times compared with basic services.

• Journal of Korea Multimedia Society
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• v.4 no.6
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• pp.562-569
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• 2001

IMT-2000 mobile system will provide many application services such as mobile internet, wireless electronics commerce applications using air interface with high data rate. These applications require high data integrity, data confidentiality, user authentication, user identity confidentiality and non-repudiation. In this study, we analyze air interface performance for network access security services in IMT-2000 mobile systems. Signal traffic for network access security services requires 0.2kbps ∼ 4.5kbps with the conditions of 246∼768bits/message, 0.2 ∼ 1.0 basic service/sec and the security services of the rate of 0.2∼ 1.0 times compared with basic services.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.451-453
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• 2001

제스쳐(gesture)는 마우스 또는 스타일러스의 난일 표시(single mark)를 이용하여 객체들과 기능들을 식별하는 문서 편집 도구의 강력한 방법들 주 하나이다. 마우스를 위한 제스쳐는 주로 데스크 팁 기반의 환경을 위해 개발되어지고 스타일러스를 위한 제스쳐는 보통 휴대용 컴퓨터를 위해 개발되어진다[2]. 현대는 PDA(Personal Digital Assistant)시스템의 스타일러스를 위한 제스쳐 개발이 활발하게 이루어지고 있다.[3]. 하지만 PDA 시스템에서는 인식에 의한 문자 입력의 보조 도구 정도의 수준에서 제스쳐가 사용되어진다. 본 논문에서는 PDA 시스템에서 사용되는 키보드의 키 역할을 하는 기존의 제스쳐와는 달리 사용자 입력과 제스쳐에 차별을 두지 않고 한 화면에서 직접적이 제스쳐가 가능한 환경을 개발하고 다양한 제스쳐 인식 방법을 제안한다. PDA 시스템에서의 제약을 최소화하기 위해 펜 기반의 입력에서 각 스트록을 간략화시켜 정보를 최소호 한 뒤 각 스트록을 양방향 연결 리스트를 이용해 연결하였다. 제스쳐(gesture)는 삽입, 삭제의 기본적인 것들을 비롯하여 이동, 복사, 붙임과 같은 제스쳐도 포함되어 있다. 제스쳐(gesture)의 인식은 각 스트록의 바운딩 박스와 점들의 위치 정보, 스트록 생성 순서에 기반하여 이루어지기 때문에, 이로 인해 펜 기반의문서 에디터 사용에서 요구되는 다른 제약 없이 오로지 펜만으로 모두 편집 환경을 구현할 수 있다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.04a
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• pp.31-31
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• 1998

위성체의 보조추진시스템은 임구궤도까지의 궤도진입 및 임무궤도상에서의 속도 또는 자세제어에 필요한 임펄스를 제공한다. 단일하이드라진 추력기는 하이드라진(H$_2$H$_4$)과 자발적 촉매(Shell 405)의 발열 및 흡열 열분해 반응에 의해 발생하는 질소($N_2$), 수소(H$_2$), 암모니아(NH$_3$), 혼합가스를 노즐을 통해 방출하므로써 요구되는 impulse를 얻는다. 단일하이드라진 추력기 설계는 주입기, 촉매대, 노즐과 기타 설계 형태에 따른 다지관, 링, 스크린, 지지판 등의 부수적인 부품으로 구성된다. 추력기 제작 과정은 크게 piece-parts 기계가공, HEA(Head End Assembly)와 TCA(Thrust Chamber Assembly)로 구성되고 각 세부공정마다 전수시험 및 검사를 가진다. 연소시험설비는 최소 모사진 공 수준이 고도 100,000 ft(8.4 torr)를 만족시킬 수 있는 진공설비, 시험제어부, 성능변수 측정 및 처리부, 추진제 가압 공급부, 기타 환경 안전 및 부대 설비로 구성된다. 추력기 연소성능시험 절차는 추진제 충전 및 오염 여부 표본 검사, 가압 및 공급 라인 이상여부 확인, 추력기 장착, 추진제 가압 및 공급, 시험장치 보정, 진공 모사 및 연소성능시험, data 처리 등으로 구성된다.

• The Korean Journal of Food And Nutrition
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• v.17 no.4
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• pp.436-441
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• 2004

As the production of agricultural products showing high quality and environmental safety is required increasingly these days, it is really necessary to study on technology for producing agricultural products which are safe microbiologically. Among several sanitizing reagents contacted easily, we investigated the most effective and useful method for reducing microorganisms by sanitizer treatment. From this study, it was showed that treatment of 3% hydrogen peroxide solution over 1 minute, which decreased microbiological level less than one tenth of natural state(no sanitizer treatment) in all microorganisms tested, was the most effective sanitizing method to green vegetables, especially raw lettuce used in this study, for reducing microorganisms. By utilizing this sanitizing method in farming step, the improvement of safety and added value of agricultural products, especially raw green vegetables, is expected.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.23-26
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• 2002

The generation of wastewood is currently about 40% level of the amount of domestic wood use. When the rate of wood self-supply is considered, the recycling of wastewood in wood panel products industry should be encouraged. This study was evaluated the performance of particleboard (PB) made from wastewood. PBs were manufactured with the synthesized urea-formaldehyde resin at 5 minutes hot-press time, and at 162℃ press temperature with 6 percent resin solids level on an ovendry wastewood particle weight basis. The PBs were tested by the procedure of ASTM D 1037. Test results exceeded the minimum strength requirement according to KS F 3104 Particleboard type 8.0. The PB's performance showed that wastewood is suitable raw material for PB.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.2
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• pp.169-179
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• 2010

Satisfying the same probability of loss of control and essentially two fail operative performance with a triplex computer architecture requires a lot of modification of the conventional redundancy management design techniques, previously employed in quadruplex digital flight control computer. T-50 FCS for triplex redundancy management design applied an advanced digital flight control architecture with an I/O controller which is functionally independent of the digital computer to achieve the same reliability and special failure analysis and isolation schemes for fail operational goals with a triplex configuration. The analysis results indicated that the triplex flight control system is to satisfy the safety requirement utilizing the advanced flight control techniques and the system performance of the implemented flight control system was verified by failure mode effect test.