• Corrosion Science and Technology
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• 제9권3호
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• pp.137-141
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• 2010

Sodium nitrite is widely used as one of the popular corrosion inhibitors for the protection of ferrous metal in closed cooling water system, such as a diesel engine and a chiller. The optimum treatment conditions are studied through laboratory tests using linear polarization resistance (LPR) technique. Corrosion rate of the carbon steel electrode could be maintained less than $2.5{\times}10^{-3}$ mmpy in the test condition of 500 ppm as ${NO_2}^-$, 200 ppm as $Cl^-$, $70^{\circ}C$ and pH 6.8. The pH control is confirmed not to be an important factor in the protection of carbon steel by sodium nitrite inhibitor. The addition of tolyltriazole was needed for the protection of the copper alloy in the sodium nitrite treatment system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.461-462
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• 2011

Overhead lines constitute an unnatural intrusion into the natural environment, and as such have an impact on it. In the case of birds, these impacts can be positive or negative, depending on the context and surrounding circumstances. Most of the negative impacts can be effectively addressed, provided the problem is well understood.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2017년도 춘계학술발표대회
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• pp.1129-1130
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• 2017

본 연구에서는 현대인들의 하루 중 많은 시간을 차지하는 착좌 생활을 관리하기 위한 롤러블(rollable) 스마트패드를 개발하였다. 이를 위해 PVDF(polyvinylidene fluoride) 필름을 이용한 압전센서(piezoelectric sensor)를 제작하였으며, 센서에서 데이터를 획득하고 및 햅틱 피드백(haptic feedback)을 주기 위한 측정시스템을 개발하였다. 또한, 스마트폰 어플리케이션을 통해 착좌 자세에 대한 정보를 실시간으로 제공하도록 하였다. 제작된 시스템의 착좌 자세 구분 정확도는 10명의 피험자를 대상으로 평가되었으며, 4가지 자세(상체를 좌, 우, 앞, 뒤로 기울인 앉은 자세)에 대한 실험결과 제작된 시스템은 92.5%의 정확도로 제시한 4가지의 자세를 구분하였다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2005년도 추계학술대회 및 정기총회
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• pp.217-220
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• 2005

과학기술이 국가경쟁력에서 차지하는 비중이 높아지면서, 국가 차원에서 과학기술역량의 확충을 위한 다양한 정책적 노력이 경주되고 있으며, 그 일환으로 정부연구개발사업과 관련된 예산도 지속적으로 증가하여 왔다. 이와 함께 최근 들어 공공부분에 책무성(accountability)에 대한 논의와 함께 성과주의 제도의 적극적인 도입이 검토되고 있다. 특히 다양한 특성을 가진 많은 정부사업들이 적절하게 추진되고 있는지 그 성과를 측정하고 관리하는 것은 책무성의 이행이라는 측면에서 상당히 중요하다. 이에 따라 성과를 보다 명확히 측정할 수 있는 도구의 필요성과 함께 균형성과표(Balanced Scorecard: BSC)가 새롭게 조명을 받고 있다. 본 연구에서는 BSC의 기본모형을 확장하여 정부연구개발사업에 적용해 보고자 한다.

• 한방안이비인후피부과학회지
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• 제22권2호
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• pp.50-59
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• 2009

Objectives : The aim of this study was conducted that CRE (Coptidis Rhizoma Extract) induces apoptosis in YD-10B cells, human oral squamous carcinoma cell line. Methods : In this study, YD-10B cells were exposed to CRE (0.03-0.30 mg/ml), for 6-24 hours. We measured the effects of CRE on the changes of cell viability and cell membrane, TUNEL assay of CRE-treated YD-10B cell. Results : In this study, CRE caused a decrease of viability in YD-10B cells, human oral squamous carcinoma cell line. When YD-10B cells were treated with CRE, cells showed dose-dependent manner apoptotic cell death. Conclusions : These results suggest that CRE may be potential therapeutic approach in the clinical management of oral squamous cell carcinoma.

• Journal of Welding and Joining
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• 제14권2호
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• pp.57-64
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• 1996

In this paper, authors are trying to find optimum spot weldig conditions to minimize indentation of the plate surface which is crucial to quality of stainless rolling stocks. At first, to derive a simple equation to estimate the depth of indentation, a simplified one-dimensional bar model is proposed and validity of the model is confirmed by experiments. And also, to find proper welding conditions giving satisfied tensile strength of the welded joint, a simple formula is derived referring to the standard spot welding conditions by AWS. Optimization problem is formulated to find welding conditions such as welding current, time and applied force which give minimum indentation and proper tensile strength of joint, and solutions are found out. According to the results, the depth of indentation can be expressed by applied electrode froces and it can be shown that an optimum applied force exists.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 2006년도 제28회 동계학술발표회 논문집
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• pp.187-204
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• 2006

According to increasing dependancy of national competitiveness on her level of science and technology, the Korean Government devote herself to expansion of technological capability in nation-wide. As a result, the numbers and sizes of national R&D programs, one of public technology policies, are abruptly increased. Recently, the government closely examines the introduction of performance-based budgeting regime as well as the accountability issue in public sector. In the fulfillment of accountability, it has considerable importance that the government executes measurement and strategic management of their performances of all the national R&D programs, how they are properly executed in conformity with respective missions and characteristics. It needs a tool for clearly measuring the programs' performances. In this study, the Balanced Scorecard (BSC) is suggested as an alternative. However, the logics of ordinary BSC cannot be directly applied to the program unit. This study reviews the basic concept and principles of BSC and discusses the necessary conditions for proper application of BSC into national R&D programs.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.538-543
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• 2000

The purpose of this study is to develope electrostatic separation system for recycling of mixed waste plastics. The electrostatic separation system is designed and investigated the separation efficiency for separating of mixed waste plastics. Electrostatic separation system consisted of a tribocharger, separator (two electrode), collector (5 tray) and controller (positive/negative high voltage power supply). The tribocharger is a fluidized bed using tribo-electrification mechanism between particles and particles. In experimental results, the tribocharger of the fluidized bed was more effective separation efficiency. It showed the purity of $85{\sim}99\;%$ and the recovery of $80{\sim}98\;%$ from the powder of mixed plastics such as LDPE, HDPE, PP, PS, PET and PVC. Especially, In the separation experiment of Polyvinylchloride(PVC) which generates hazardous hydrogen chloride gas in case of the combustion. its purity was over 99 % and recovery was over 95 %.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.520-525
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• 2000

This research is to analyze the ventilation performance of mechanical ventilation systems for indoor air quality control and management. A ventilation performance with supply sites is evaluated in a test model chamber and office room. A $CO_2$ gas as a tracer gas is used to measure the ventilation performance. The ventilation performance is found to increase with increased the ventilation rate. The ventilation performance is analysed with 55% at the supply air of 570 lpm and with 20% at the supply air of 100 lpm in a test chamber. The ventilation performance is better than 15% comparing with natural decay at the supply of 570 lpm in office room.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1869-1874
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• 2003

Polymeric fibers with nanometer-scale diameters are produced by electrospinning. When the electrical forces at the surface of a polymer solution or melt overcome the surface tension then electrospinning occurs. Polyethylene oxide (PEO), Polycarbonate have been electrospun in our laboratory. Electrospun fibers are observed by optical microscopy or scanning electron microscopy. The average diameters of the electrospun fibers range from 300 nm to 30 nm when the electric field strength increasing from 1 kV/cm to 3 kV/cm. The average diameters of the electrospun fibers range from 200 nm to 30 nm when the concentration decreasing from 10 wt% to 4 wt%.