• 한국응용과학기술학회지
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• 제35권4호
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• pp.1048-1056
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• 2018

비식용 원료인 Palm Acid Oil, 동물성 폐유지 등은 상대적으로 자유 지방산 함량이 높기 때문에 일반적인 염기 촉매를 이용한 전이에스테르화 반응에 적합하지 않다. 효소 촉매를 이용하면 염기 촉매에서 해결할 수 없는 몇 가지 문제를 해결할 수 있으며, 에너지 소비가 작고, 바이오디젤 부산물인 글리세롤 회수가 쉬우며, 자유 지방산 함량이 높은 트리글리세라이드에 대한 전이에스테르화 반응이 가능하다. 본 연구에서는 고정화 효소 촉매를 이용하여 1 ton/day 용량의 반응기에서 비식용 폐유지를 바이오디젤로 합성하였으며, 반응 공정의 변수를 최적화하였다.

• 한국항만경제학회지
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• 제17권1호
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• pp.53-72
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• 2001

This study focuses on analyzing the economic effects and probes the necessity of establishing a customs free zone at the Port of Busan. It first considers the economic effects of establishing a customs free zone at the Port of Busan, then suggests policy prescriptions for introducing and operating the free zone system and improving the logistics functions of the Port. The timeline of this study is focused on 2007, when all of Busan Port will operate as a customs free zone and the first stage of the New Busan Port and distribution parks will be built and opened for operation. The regression analysis, which was conducted using the inter-industry relations table(input-output table data), provided a quantitative prediction on the effects of making Busan Port into a customs free zone. Regarding the impact of a free zone system on the domestic and regional economy, this research found that the impact of a customs free zone on domestic industries and the regional economy once the customs free zone is established throughout all of Busan Port would be highly positive. The positive economic effects on the domestic and Busan regional economy might be further strengthened if the value-added logistics function of Busan Port could be supplemented by effective linking to the hinterlands.

• 한국수학교육학회지시리즈A:수학교육
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• 제26권1호
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• pp.61-66
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• 1987

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1993년도 춘계공동학술대회 발표논문 및 초록집; 계명대학교, 대구; 30 Apr.-1 May 1993
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• pp.225-225
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• 1993

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1993년도 추계학술대회발표논문집; 서강대학교, 서울; 25 Sep. 1993
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• pp.105-105
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• 1993

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.3941-3942
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• 2012

• Journal of Biosystems Engineering
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• 제20권1호
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• pp.58-65
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• 1995

A numerical study for a two dimensional multi-jet with crossflow of the spent fluid has been carried out. Three different distributions of mass-flow rate at 5 jet exits were assumed to see their effects upon the flow characteristics, especially in the jet-flow region. For each distribution, various Reynolds numbers ranging from laminar to turbulent flows were considered. Calculations drew the following items as conclusion. 1) The development of the free jets issued from downstream jets was hindered by the crossflow formed due to jets. Consequently, the free jet was developed into the channel flow without any evident symptom of impingement jet flow characteristics 2) The crossflow induced the pressure gradient along the cross section of jet exits and the value of the pressure gradient increased as going downstream. The crossflow generated also the turbulent kinetic energy as it collied with the downstream jets. 3) The skin friction coefficient along the impingement plate was affected more by the distribution of mass flow rate at jet exits rather than by the Reynolds number. The skin friction coefficient was inversely proportional to the square root of the Reynolds number, regardless of flow regime when a fully developed flow was formed in the jet flow region. 4) The distribution of the skin friction coefficient along the impingement plate was found to be controlled by adjusting the distribution of mass flow rate at jet exits.

• 유통과학연구
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• 제19권7호
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• pp.19-27
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• 2021

Purpose: Former research has argued that organizations in distribution channels face several issues to make a better team-based system. The purpose of the present research is to measure between employee's job performance and three major issues which disturb a solid team system. Research design, data and methodology: Scant past studies are available to guide for team practitioners which elements should be eliminated to improve team performance. To achieve this goal, the present authors obtained 267 US workers in distribution channels and conducted ANOVA test to measure the relationship between three team issues (Free-rider, Trust, and Communication) and job performance. Results: Our statistical findings clearly suggests that there was a statistically recognizable difference at the significance level of probability between the mean value of employees' job performance and three major issues, showing the high degree of job performance can be occurred by eliminating three major team issues. Conclusions: Therefore, the present research concludes that it is necessary that team-based management in the supply chain should focus on removing free-rider issues and also adopt open communication lines to overcome team-building challenges due to communication. Above all else, the ability to increase trust can be enhanced via task delegation and more team members' engagement.

• Advances in nano research
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• 제11권6호
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• pp.621-640
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• 2021

Effect of thickness stretching on mechanical behavior of functionally graded (FG) carbon nanotubes reinforced composite (CNTRC) laminated nanoplates resting on elastic foundation is analyzed in this paper using a novel quasi 3D higher-order shear deformation theory. The key feature of this theoretical formulation is that, in addition to considering the thickness stretching effect, the number of unknowns of the displacement field is reduced to four, and which is more than five in the other models. Single-walled carbon nanotubes (SWCNTs) are the reinforced elements and are distributed with four power-law functions which are, uniform distribution, V-distribution, O-distribution and X-distribution. To cover various boundary conditions, an analytical solution is developed based on Galerkin method to solve the governing equilibrium equations by considering the nonlocal strain gradient theory. A modified two-dimensional variable Winkler elastic foundation is proposed in this study for the first time. A parametric study is executed to determine the influence of the reinforcement patterns, power-law index, nonlocal parameter, length scale parameter, thickness and aspect ratios, elastic foundation, thermal environments, and various boundary conditions on stresses, displacements, buckling loads and frequencies of the CNTRC laminated nanoplate.

• 산경연구논집
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• 제3권1호
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• pp.25-29
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• 2012

The purpose of this study is to examine the development of the pharmaceutical distribution industry. The pharmaceutical industry is are expected to suffer a heavy blow when the Free Trade Agreement (FTA) is introduced, despite its best efforts. Therefore, adequate solutions must be found. Section II introduces the Korean pharmaceutical distribution system and its current situation; Section III explores the distribution system's strengths and weaknesses. Section IV, identifies the problem and possible solutions for the Korean pharmaceutical distribution system; Section V summarizes and concludes this paper and acknowledges its limitations. Finally, this paper has a clear limitation. The lack of objective information and scientific analysis due to the data being based on interviews with company representatives is its most significant shortcoming. However, it offers implications for new directions for future research.