• 전자공학회논문지A
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• 제32A권9호
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• pp.1167-1176
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• 1995

This paper suggests a method for optimal power assignment of the satellite transponder input carriers in the Multi-level & Multi-bandwidth system. The interference and the noise effects analyzed for the optimal power assignment are intermodulation product caused by the nonlinear transponder characteristics, adjacent channel interference, co-channel interference, and thermal noise in the satellite link. The Fletcher- Powell algorithm is used to determine the optimal input carrier power. The performance criteria for optimal power assignment is classified into 4 categories according to the CNR of destination receiver earth station to meet the requirement for various satellite link environment. We have performed mathematical analysis of objective functions and their derivatives for use in the Fletcher-Powell algorithm, and presented various simulation results based on mathematical analysis. Since the satellite link, it is meaningful to model and analyze these effects in a unified manner and present the method for optimal power assignment of transponder input carriers.

• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2479-2482
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• 2010

Using a pinhole-type glass nozzle equipped for a corona-excited supersonic expansion (CESE), precursor 2,6-dichlorotoluene seeded in a large amount of inert carrier gas helium was discharged to produce jet-cooled but electronically excited benzyl-type radicals. The visible vibronic emission spectrum was recorded with a long-path monochromator to observe vibronic bands in the $D_1{\rightarrow}D_0$ electronic transition of benzyl-type radicals. The spectral analysis revealed the generation of not only the 2,6-dichlorobenzyl radical as a typical product, but also the o-chlorobenzyl radical as an unexpected species, which indicates the possible molecular rearrangement in eliminating a chlorine atom from the benzene ring. A possible mechanism is proposed for the formation of the o-chlorobenzyl radical from the precurs or in the gas phase.

• 대한조선학회논문집
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• 제34권2호
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• pp.48-55
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• 1997

본 논문은 초기설계 단계에서 HPMM시험을 이용하여 조종성능을 추정하기 위해서 Abkowitz와 MMG 수학모델을 비교하였다. 본 논문에서 MMG 해석에 의한 알고리즘은 일본의 MMG 그룹의 해석 방법을 적용하여 연구되었다. 해석 결과는 정유운반선을 대상선박으로 선정하여 Abkowitz 수학모형 및 실선 시운전 결과와 비교 되었다.

• 항공우주시스템공학회지
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• 제10권2호
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• pp.27-33
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• 2016

For the continued airworthiness of aviation products, aviation authority requires that every manufacturer should provide ICA(Instruction of Continued Airworthiness) to their users, and the users should follow it by themselves or using another approved maintenance agent. To reduce the cost and improve performance quality of maintenance activities, lots of users tries to outsource this job. To perform maintenance or repair of other owned air products, an air carrier and aviation maintenance companies should obtain AMO(approval of maintenance organization). It means AMO is a postulation to enter MRO(Maintenance Repair and Overhaul) market. For that, this paper discusses the comparison of requirements and procedures of AMO system between Korea and US to help understand the AMO system, and then, tries to point out what improvement should be made to Korean AMO system to be more effective, efficient and safe.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.797-803
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• 2000

Recently, the singing phenomenon was encountered during the sea trials of high speed catamaran and 46,000 TDW product carrier and remedied after various treatments, which were based on the reduction of vortex shedding strength and the avoidance of resonance, respectively. And, the numerical approach for structure-acoustical problem like singing phenomenon was established using MSC/NASTRAN and SYSNOISE. In this paper, the effectiveness of numerical approach was verified through the control of singing noise. And the results according to the modification were also discussed. Finally, the future works were described to enhance the numerical approach pattern for singing phenomenon.

• Biomolecules & Therapeutics
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• 제7권2호
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• pp.170-177
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• 1999

PEG-hemoglobin SB1 (SB1), which is a hemoglobin-based oxygen carrier, is intended to use as a safe blood substitute against brain ischemia and stroke. The general pharmacological profiles of SB1 were studied. The doses given were 0, 5, 10, 20 ml/kg and drugs were administered intravenously. The animals used for this study were mouse, rat and guinea pig. SB1 showed no effects on general behavior, motor coordination, spontaneous locomotor activity, hexobarbital sleeping time, anticonvulsant activity, analgesic activity, blood pressure and heart rate, left ventricular peak systolic pressure, left ventricular end diastolic pressure, left ventricular developing pressure, double product, heart rate, coronary flow rate, smooth muscle contraction using guinea pig ileum, gastrointestinal transport, gastric secretion, urinary volume and electrolyte excretion at all doses tested except the decrease of body temperature. These findings demonstrated that SB1 possesses no general pharmacological effects at all doses tested.

• 한국영양학회:학술대회논문집
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• 한국영양학회 1995년도 춘계심포지움 및 학술발표논문 초록
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• pp.21-21
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• 1995

Absorption of fat-soluble vi tamin, retinol occurs mainly in the proximal part of small intestine. But its intestinal transport mechanism isn't yet clear. The aim of the present study was to investigate on the mechanism of absorption of retinol by determining a concentration-dependent kinetic of retinol absorption in rats. The study was carried out by applying in vivo technique in which vitamin solution was infused to intestinal lumen and at the same time thoracic duct and choledochus duct were canulated to collect samples. The investigations showed that retinol is absorbed in the small intestine by a saturable, carrier-mediated transport system, i.e. wi thout signi ficant differences between the proximal and distal halves of the small intestine. The transport of retinol taken up by the enterocytes occured via different mechanisms: while the main vitamin A transport via the thoracic duct was saturated by limiting transport factors such as retinol-CRBP-II-complex formation and retinol esterification with increasing substrate concentrations, the transport of retinol metabolite product via the portal vein was proportional to the substrate concentration.ration.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 추계학술대회논문집
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• pp.252-255
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• 2004

Design modification of the stamping die for the upper member of a front end module carrier is carried out in order to improve the feeling qualify of the final product. The small inferiority induced by wrinkling near the wall of the FEM upper member has been inspected after the draw-forming process. The finite element simulation shows that the excess metal is developed by the irregular contact of the blank the tool and it remains after the final stroke. This paper proposes two guidelines for the modification: one is to add the draw-bead; and the other is to modify the tool shape such as the forming shape at the wall. Simulation results show that the proposed guidelines both guarantee the improved feeling quality.

• 한국수소및신에너지학회논문집
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• 제28권5호
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• pp.453-458
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• 2017

A study on the modeling of the methane Chemical Looping Reforming system was carried out. It is aimed to predict the temperature and concentration behavior of the product through modeling of oxygen carrier fixed bed reactors composed of multiple stacks. In order to design the reaction system, first of all, the flow rate of the hydrogen to be produced was calculated. The flow rate ratio of the oxidation/reduction reactor was calculated considering the heat of reaction between adjacent reactors. Finally, in this paper, kinetic model including empirical coefficients was suggested.

• 반도체디스플레이기술학회지
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• 제4권4호
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• pp.27-31
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• 2005

This article contains the development of FPC bonder that used for repair or trial product. Nowadays, in FPO module process (including PDP) accept the thermo-compress bonding method when attach FPC(Flexible Printed Circuit Board), TCP(Tape Carrier Package) and COF(Chip on the FPC) by ACF(Anisotropic Conductive Film). This system consists of ACF attachment part, pre-bonding part, main bonding part, loading / unloading part. This composition is a stand-alone system, not an in-line system. Hereafter, this composition should be developing into in-line system in all area of FPD industry.