• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2002년도 금형가공 심포지엄
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• pp.95-102
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• 2002

With recent trends leaning towards product miniaturization, the advent of new material and speedy delivery times, old style conventional trial-and-error methods have been only serving to weaken corporate competitiveness. Reliant on tiny increments of time-consuming experience, this antiquated approach begets a delayed delivery of product development, cost loss and quality depreciation. To solve such problems, the Dedicated Injection Molding CAPA (Computer Aided Plastics Application) performs a preliminary examination on problems rising from every stage of creation - from appropriate material selection and mold design to mass production - through a computer system. Thus, it determines the optimum design variables and process conditions while diagnosing and solving defective molds.

• Corrosion Science and Technology
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• 제7권3호
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• pp.158-161
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• 2008

It is well known that iron is one of the most common impurity elements found in aluminum and its alloys. Iron in the aluminum forms an intermetallic compounds such as $FeAl_3$. The $FeAl_3$ particles on the aluminum surface are one of the most detrimental phases to the corrosion process and anodizing procedure for aluminum and its alloys. Trial and error surface treatment will be carried out to find the preferential and effective removal of $FeAl_3$ particles on the surfaces without dissolution of aluminum matrix around the particles. One of the preferable surface treatments for the aim of getting $FeAl_3$ free surface was an electrochemical treatment such as cathodic current density of $-2kAm^{-2}$ in a 20-30 mass% $HNO_3$ solution for the period of 300s. The corrosion characteristics of aluminum surface with $FeAl_3$ free particles are examined in a $0.1kmol/m^3$ NaCl solution. It is found that aluminum with free $FeAl_3$ particles shows higher corrosion resistance than aluminum with $FeAl_3$ particles.

• 대한기계학회논문집
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• 제18권5호
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• pp.1338-1346
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• 1994

The objective of this study is to investigate the effect of various parameters, such as temperature, mean current density and voltage on the performance of phosphoric acid fuel cell (PAFC) by numerical analysis. Two types of flow passages, which are Z-parallel type and Z-counter type, are evaluated to obtain the best current density and temperature distribution. Parametric studies and sensitivity analysis of the PAFC system's operation in single cell are accomplished. A steady state simulation of the entire system is developed using nonlinear ordinary differential equations. The finite difference method and trial and error procedures are used to obtain a solution.

• 한국항해항만학회지
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• 제36권2호
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• pp.131-140
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• 2012

Since 2000, S. Korea is building yachts through government supported localization, cooperation between industry and educational organizations, or partnerships with foreign firms but the yacht building has yet only accomplished trial manufactured ships and one-time production. Because of a lack of mass production, the industry assesses the domestic technical skills to an average 50~60% of developed countries and its market share is less than 1% in the world. In addition, domestic marine equipment is heavily depending on imports and the industry is experiencing shortage of technology and experts, small-sized companies, insufficient industry and educational organizations' cooperation networks, inadequate legislation and policies, deficient domestic market vitalization, and scarce international information. Thus, this study focuses on the alternative plans to strengthen competitiveness and to cope with problems in the southeast marine leisure equipment industry.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.101-103
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• 1994

This report describes CRDCM(Counter Rotating DC Motor) that we have designed, manufactured and tested. CRDCM have two rotating rotors: one is a outer rotor as field set, another is a inner rotor as armature set. One of the most difficult problem is an elimination of the centrifugal force acting on brush when outer rotor is rotated. We solved a problem for centrifugal force of commutation brush by compensation set of counter mass through trial and error. It was verified the performance of motor at present.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2023년도 춘계학술대회
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• pp.263-264
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• 2023

본 연구는 자율운항선박의 실제 해상에서의 성능 검증하기 위한 실험을 진행하였다. 먼저 SAS(Samsung Autonomous System)을 활용하여 시뮬레이션을 진행하였다. 시뮬레이션은 Imazu 조우 모델을 기반으로 실험을 진행하였다. 시뮬레이션에서 조우 선박은 2-4척으로 정면, 횡단, 추월 등이 뒤섞인 상황을 가정하였다. 결과 분석은 6가지 항목(속력, Heading, Rate of Turn, Collison Risk Index, DCPA, TCPA, Closest Distance, XTD(Cross-Track Distance))을 분석하였다. 2 차례의 실해역 실험을 진행하였다. 목포-제주도 구간에서 실해역 실험을 진행 후 목포-이어도-독도 항로에서 실해역 실험을 진행하였다. 실해역 실험 결과 Imazu 모델 기반 시뮬레이션과 비슷한 결과를 보였다.

• 한방비만학회지
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• 제11권1호
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• pp.1-14
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• 2011

Objectives This trial was conducted to evaluate the efficacy of Red Ginseng by oriental medical obesity syndrome differentiation on obese women as compared to placebo. Methods 50 obese women were recruited and randomized to receive Korean Red Ginseng(n=24) or placebo(n=26) for 8 weeks. Anthropometric factors, serum lipid, glucose, blood pressure, pulse rate, resting metabolic rate, Korean version of obesity-related quality of life(KOQOL) scale and oriental medical obesity syndrome differentiation questionnaire were measured at baseline and 8 weeks. Adeverse events and safety outcomes variables were also checked during trials. Results and Conclusion There was significant efficacy of Red Ginseng on obese women in body weight, body fat mass, waist-hip ratio, food intake, KOQOL as compared with baseline. But there was no efficacy as compared with placebo group except KOQOL. There was no difference of efficacy compared with the oriental medical obesity syndrome differentiation.

• 한방비만학회지
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• 제10권1호
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• pp.1-16
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• 2010

Objectives The clinical trial was designed to investigate the safety and effects of Bofu-tsusho-san extracts on the change of the weight, body compositions, serum in obese patients. Methods This study was a 4-weeks, double blind, comparative clinical trial. Eligible subjects had a body mass index(BMI) greater than $25\;kg/m^2$ and waist circumference(WC) longer than 85 cm in woman or 90 cm in man. Among 38 subjects, 36 subjects were randomized either to Bofu-tsusho-san or placebo. After 4 weeks of treatment, we measured anthropometric factors(weight, height, WC, BMI etc.), abdominal fat area by CT scanning, serum lipid(total cholesterol(TC), triglyceride(TG), HDL cholesterol, LDL cholesterol), blood level of variety(glucose, adiponectine, leptin, C-reactive protein(CRP) etc.), blood pressure(BP). Adverse events also evaluated. Results BMI, BP, TG, CRP were reduced and weight, WC, score of KOQOL(Korean version of obesity-related QOL scale), SRI(Stress response inventory) were significant changed in Bofu-tsusho-san. But there were no considerable difference between Bofu-tsusho-san and placebo. there were no serious adverse events in either group. Conclusion There were limitations in this study that it conducted within a short period of 4 weeks. but its weight and WC loss effect was significant and it had few adverse events.

• 대한한방내과학회지
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• 제35권2호
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• pp.157-174
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• 2014

Objectives : The aims of this study were to evaluate the diagnostic values of tongue coating thickness and sterno-costal angle as the quantitative diagnostic indicators in functional dyspepsia. Methods : We surveyed 60 functional dyspepsia patients recruited by the clinical trial, 'Clinical Trial for Evaluation on Availability of tongue diagnosis system (CTS-1000) : a Pilot study'. The patients were classified into three groups according to Rome III criteria for functional dyspepsia, and categorized into five groups according to Instrument of pattern identification for functional dyspepsia. Nepean dyspepsia index-Korean version (NDI-K) score, tongue coating thickness (percentage of tongue coating by tongue diagnosis system (CTS-1000), and weight of tongue coating by microbalance), sterno-costal angle, duration of illness and body mass index (BMI) were investigated. Results : Among the 5 types by instrument of pattern identification for functional dyspepsia, a significant difference of percentage of tongue coating was found. Percentage of tongue coating and weight of tongue coating showed significant correlation with total NDI-K score. Sterno-costal angle showed strong positive correlation with BMI and also showed significant difference between the non-overweight (BMI<23, n=32) and overweight ($BMI{\geq}23$, n=28) groups. Conclusions : Tongue coating thickness showed its potential as a new quantitative diagnostic indicator of functional dyspepsia. Further studies on the sterno-costal angle are anticipated to evaluate its potential as a new quantitative diagnostic indicator.

• Journal of Microbiology and Biotechnology
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• 제25권10호
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• pp.1761-1767
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• 2015

Sevenband grouper, Epinephelus septemfasciatus, is becoming an important aquaculture species in Korea. However, viral nervous necrosis disease is a large problem causing mass mortality in sevenband grouper aquaculture. Recombinant protein vaccines are one of the best methods to reduce these economic losses. However, the cell-based expression method mainly produces inclusion bodies and requires additional procedures. In this study, we expressed a recombinant viral coat protein of sevenband grouper nervous necrosis virus (NNV) using a cell-free protein synthesis system. The purified recombinant NNV coat protein (rNNV-CP) was injected into sevenband grouper at different doses followed by a NNV challenge. Nonimmunized fish in the first trial (20 μg/fish) began to die 5 days post-challenge and reached 70% cumulative mortality. In contrast, immunized fish also starting dying 5 days postchallenge but lower cumulative mortality (10%) was observed. Cumulative morality in the second trial with different doses (20, 4, and 0.8 μg/fish) was 10%, 40%, and 50%, respectively. These results suggest that rNNV-CP can effectively immunize sevenband grouper depending on the dose administered. This study provides a new approach to develop a recombinant vaccine against NNV infection for sevenband grouper.