• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.1033-1037
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• 2008

A copper cyclam-type complex was successfully immobilized onto mesoporous silica SBA-16. Characterization by NIR spectroscopy and TGA analysis confirmed that copper cyclam complex is immobilized onto mesoporous SBA-16. The Cu(II)-Cyclam-SBA-16 was proven to be a good catalyst for oxidation reaction of cyclohexene with conversion up to 77.8% after 13 h reaction and providing a high selectivity to cyclohexenol and 3-hydroperoxycyclohex-1-ene. The results suggest that the copper species play a major role as catalyst via reversible redox cycles as proven by cyclic voltammetry analysis.

• 한국전산유체공학회:학술대회논문집
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• 1999.05a
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• pp.171-176
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• 1999

In the present paper, three types of the flow solvers were used to investigate the influence on the airfoil shape optimization. The adopted equations, i.e., Euler , thin layer Navier- Stokes and full Navier-Stokes ones, are solved using implicit LU-ADI decomposition scheme. The feasible direction algorithm with the sinusoidal function was used as an optimization algorithm. The present numerical method was applied to the drag minimization problems under the initial shape of NACA0012 airfoils.

• Solar Energy
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• v.6 no.2
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• pp.76-85
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• 1986

The study on the characteristics of heat transfer by various working fluid and wick structure is an important subject in order to design low temperature heat pipe. The purpose of this research was to study the heat transfer characteristics of heat pipe according to various working fluid and wick thickness by ADI method and experimental results. As the results the heat transfer by various working fluid could improve by good heat conductivity of fluid and small ratio t/k. The working fluid could be selected in close vicinity to boiling temperature among fluid properties the value of ratio little influenced heat transfer of heat pipe. In case of distilled water, the response of the effect in heat recovery was more rapidly showed than response of other working fluid. The maximum heat flux increased in proportion to the characteristics of working fluid but the pore and wick permeability among wick characteristic was little effect in the wetting state.

• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.685-694
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• 2005

Korean practices in tolerance setting of pesticide residues on food crops were compiled with an effort to harmonize with international standards. Based on scientific data including historical background, limit setting protocols, adoption of ADI values, food factors, nation's body weights, and regulatory margins which are required for the setting of maximum residue limits, necessary measures to be taken by Korean regulatory authorities were proposed.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.2
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• pp.313-324
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• 1992

Two-dimensional Navier-Stokes code has been developed for analysis of turbomachinery blade rows and other internal flows. The Navier-Stokes equations are written in a Cartesian coordinate system, then mapped into a generalized body-fitted coordinate system. All direction of viscous terms are incorporated and turbulent effects are modeled using the Baldwin-Lomax algebraic model. Equation are discretized using finite difference method on the C-type grids and solved using implicit LU-ADI decomposition scheme. Calculations are made at a VKI turbine cascade flow in a transonic wind-tunnel and compared to experimental data. Present numerical scheme is shown to be in good agreement with the previous experimental results and simulates the two-dimensional viscous flow phenomena.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1998.05a
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• pp.315-320
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• 1998

n명의 사용자들 중 k명 이상이 모이면 시스템의 비밀정보가 재구성 되는 시스템을 threshold cryptosystem 이라고 한다. 1979년 Adi Shamir에 의해 threshold 개념이 제안된 이래로, 그 현실적인 효용성때문에 많은 연구들이 이루어져 왔다. Threshold cryptosystem을 구성하기 위해서는 n명의 사용자들이 각자의 share를 가지고 있어서 그 중 k명 이상이 자신의 share를 밝히면 시스템의 비밀정보가 재구성된다. 그러나, 시스템의 비밀정보가 재구성 된 후에는 각 사용자들의 share를 재분배해야 한다. 이러한 특성은 반복적으로 전자서명과 같은 비밀연산을 수행해야 하는 응용에서는 비현실적이 된다. 이러한 경우에 적용시키기 위한 암호시스템이 threshold signature이다. (t, n)-threshold signature 시스템에서는 n명의 사용자들 중 k명 이상이 자신의 share를 이용한 부분서명을 수행하면 전체 시스템 서명이 생성된다. 그러나, 시스템의 비밀정보는 재구성 되지 않으므로 아무도 알 수 없고, 따라서 재분배 할 필요가 없다. 본 논문에서는 이러한 threshold signature 시스템에 대한 연구결과들을 살펴본다.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.625-628
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• 1998

The dynamic mechanical properties of the unclustered cesium neutralized poly(methyl methacrylate-co-methacrylic acid) ionomers plasticized with three different plasticizers of low molecular weight were investigated. It was found that the effectiveness of the plasticization followed the order: glycerol (Gly) 4-decylaniline (4DA) >dioctyl phthalate (DOP). For the ionomer plasticized with Gly, the only effect was a significant decrease in the Tg. Thus it is concluded that the polar plasticizer not only increases the mobility of the ionomer but also dissolves the ionic groups. In the case of the 4DA-plasticized ionomer, both a drastic decrease in the Tg and the appearance of a second glass transition were observed. Therefore, it is suggested that the nonpolar 4DA molecules partition evenly in the poly(methyl methacrylate) matrix and cluster phases via hydrogen bonding between the aniline group of the plasticizer and the carbonyl groups of the ionomer. As a result, the Tg is lowered, multiplets can form, and the material behaves like a clustered ionomer.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1995.11a
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• pp.87-96
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• 1995

인공위성의 궤도진입에 사용되는 액체추진제 로켓엔진의 개발에서 분사기 설계를 적절히 수정, 보완 할 목적으로 수행된 핵심부품별 유동해석의 내용이 기술되었다. 단일 격자계를 구성하기 어려운 복잡한 형상의 분사기 유동장에 대한 격자계 구성을 용이하게 하고, 3차원의 점성 유동해석을 컴퓨터 기억 용량에 제한없이 수행하기 위한 다중블럭 격자기법이 사용되었다. 분사기의 내부유동은 3차원 비압축성 Navier-Stokes 방정식으로 pseudocompressibility 방법을 이용하여 수치모사되었다. 정상상태의 해는 근사 인자분해에 의한 ADI 기법으로 계산되고, 공간미분항에 대해 nonstaggered 격자계에서 2차 중앙차분을 사용하며 수치해의 안정성을 위해 인공점성항을 추가하였다. 난류계산을 위해 Baldwin- Lomax의 대수적 난류모델에 다수의 벽면효과를 고려하였다. 해석결과는 분사기의 성능에 영향을 미칠 수 있는 유동조건에 따라 분석되었다.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.293-302
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• 2021

Being able to survive during the Covid19 pandemic is a big task for a company, as such, empowerment of employees is a must. The sample in this study was 300 employees who worked in Spas throughout Bali. The sampling technique was purposive sampling. Data analysis was using SEM and SMARTS as data processing. The results showed that green communication, namely communication that occurs between employees, superiors, and the environment, has a very good influence on the sustainability of employee performance. To become green management, a green organizational commitment that cares about the safety of employee health and the environment is an important factor as motivation in green dedication or positive employee productivity, but communication between work actors and justice is also a motivating factor. Work safety and job security for employees empower employees (which is a green line), especially for freelance work organizations so that further research in subsequent studies can make samples in a more varied industrial sector.

• Microbiology and Biotechnology Letters
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• v.46 no.4
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• pp.430-433
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• 2018

Hepatitis B is a major health problem in China. However, little is known about the prevalence of hepatitis B virus (HBV) in Kaifeng, the major urban capital of Henan province, China. We found that HBV prevalence increased with age and that chronic HBV was predominant in adult males in Kaifeng. The HBV prevalence remained unchanged over a 5-year period for all age groups. Alarmingly, 25% of the population remained unvaccinated and potentially susceptible to future HBV infection. HBV immunization and health education initiatives should be carried out in this population to further reduce the overall prevalence of HBV.