• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.514-520
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• 2000

Numerical simulation is conducted to clarify the heat transfer and fluid flow characteristics of HVAC(Heating, Ventilating and Air-Conditioning) for Mugunghwa passenger car. The HVAC system is installed under the floor of carbody. This new HVAC system has a lot of merits in respect of the center of gravity of carbody, flow induced noise and reduction of condensation water etc. The standard k-epsilon turbulent model and SIMPLEC algorithm based on finite volume method are used to solve the physical HVAC model. To assure convergence, QUICK scheme for momentum equation and the first order upwind scheme for turbulent equations are used. From the results of simulation, the temperature and velocity magnitude are also distributed uniformly in the interior of car.

• 한국정밀공학회지
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• 제17권9호
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• pp.122-132
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• 2000

A simplified modeling approach of forced vibration for occupied car seats was demonstrated by using a mathematical model presented in 'Free Vibration of Car seat and Mannequin System' nonlinear and linear equations of motions were rederived for forced vibration and the transfer function was used to calculate the frequency response function. The experimental apparatus were set up and hydraulic shaker was used to obtain the system responses. Through the tests mannequin's head had a lot of problems and the responses with a head and without a head were measured. To explore the effects of linear dampings and friction moments at the joints linear analyses were performed. New sets of linear spring and damping coefficients and torsional dampings at the joints were calculated through parameter study to match up with experimental results. Good agreement between experimental and simulation frequency response estimates were obtained both in terms of locations of resonances and system deflection shapes at resonance indicating that this is a feasible method of modeling seated occupants.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1997년도 추계학술대회논문집
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• pp.109-113
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• 1997

The purpose of this study is to survey colors of background, marker, and pointer being used in passenger car's display panel, and to suggest ergonomic design guidelines of car's display panel to enhance driver's visibility. An experiment was conducted, in which reading time of display was measured as dependent variable, and colors of black, white, blue and green were selected as background colors of display, and black, white, yellow, and green as marker's colors, and black white, yellow, green and red as pointer's colors. The results showed that reading time of display with white background, yellow marker and pointer was shortest. It was expected that this results could be used as valuable design guidelines in car's display panel.

• Asia pacific journal of information systems
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• 제29권4호
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• pp.673-689
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• 2019

The Internet enables businesses to acquire a great deal of information, including prices in the open markets. In this study, we investigate what the value of reference price information is to a company in the market and how the company can make use of such information. Using business analytics, we were able to estimate prices of used cars for a rent-a-car company. The results show that a smart pricing information system is useful for collecting online reference price information and for estimating future prices of used cars and rental prices.

• 한국ITS학회 논문지
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• 제12권6호
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• pp.22-28
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• 2013

본 연구에서는 대전광역시를 대상으로 향후 카쉐어링 서비스를 제공할 경우를 가정하고 위치 선정방안을 제시하는 것을 목적으로 한다. 이를 위해 GIS Arc/Info 10 소프트웨어를 활용하여 대전광역시 전역을 $500m{\times}500m$ 크기의 셀로 구분하고 카쉐어링 서비스에 영향을 미칠 것으로 예상되는 요인들을 선정하고 각 요인들의 값을 표준화하는 과정을 거쳤다. AHP 기법을 도입하여 각 요인별 가중치를 전문가 설문을 통해 결정하고 모든 셀($500m{\times}500m$ 크기)별로 적합도 지수를 산정하였으며, 네트워크 분석(Network Analysis)모듈에 내장되어있는 입지배분모델(Location-allocation Model)을 이용하여 서비스 시설의 위치를 30개의 권역으로 선정하는 방안을 제시하였다. 본 연구에서 제안한 카쉐어링 서비스 위치선정을 위한 방안은 향후 카쉐어링 서비스가 도입될 때 기초 자료로 활용할 수 있을 것으로 기대되며, 향후 적정한 수요의 추정과 경제성 검토 등에 대한 추가연구가 필요할 것으로 판단된다.

• The Korean Journal of Physiology and Pharmacology
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• 제24권1호
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• pp.27-37
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• 2020

Neuroinflammation is an important process underlying a wide variety of neurodegenerative diseases. Carvacrol (CAR) is a phenolic monoterpene commonly used as a food additive due to its antibacterial properties, but it has also been shown to exhibit strong antioxidative, anti-inflammatory, and neuroprotective effects. Here, we sought to investigate the effects of CAR on inflammation in the hippocampus and prefrontal cortex, as well as the molecular mechanisms underlying these effects. In our study, lipopolysaccharide was injected into the lateral ventricle of rats to induce memory impairment and neuroinflammation. Daily administration of CAR (25, 50, and 100 mg/kg) for 21 days improved recognition, discrimination, and memory impairments relative to untreated controls. CAR administration significantly attenuated expression of several inflammatory factors in the brain, including interleukin-1β, tumor necrosis factor-α, and cyclooxygenase-2. In addition, CAR significantly increased expression of brain-derived neurotrophic factor (BDNF) mRNA, and decreased expression of Toll-like receptor 4 (TLR4) mRNA. Taken together, these results show that CAR can improve memory impairment caused by neuroinflammation. This cognitive enhancement is due to the anti-inflammatory effects of CAR medicated by its regulation of BDNF and TLR4. Thus, CAR has significant potential as an inhibitor of memory degeneration in neurodegenerative diseases.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.259-262
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• 2008

This paper introduces a simplified method to consider forming effects in a car crash analysis. Representative value was used to consider forming effects simply. Four representative values, which are the mean value of thicknesses and effective plastic strains at nodes, the median of thicknesses and effective plastic strains at nodes, were evaluated. A crash analysis of a front side member shows that analysis results from the suggested methods are similar to those from the conventional method to consider forming effects. Use of the mean effective plastic strain shows the best results. A car crash analysis for a ULSAB/AVC model under the condition of US SINCAP were carried out to demonstrate the validity of the suggested method. Analysis results show that the error of suggested method is less than 1.5%.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1816-1821
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• 2003

The thermoelectric device was applied to a car-seat to control the hot temperature in summer and cold temperature in the winter. The characteristics of the device used to a car-seat were analyzed. The air conditioning structure was designed to regulate the hot side of the thermoelectric device. To control the temperature of the car-seat, a robust control algorithm based on the sliding mode control was applied, and a controller using one-chip microprocessor was developed. The performance of the proposed controller through experiments was shown.

• 한국정밀공학회지
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• 제33권4호
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• pp.317-324
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• 2016

Stress tests were conducted in the carbody of the railroad car to check the structural strength of the body of the railroad car. The objective of this study was to evaluate safety of the carbody of a railroad car under the maximal strength. The carbody of rolling stock is a principal structure that supports major equipment of the underframe and the freight. Therefore, the strength evaluation of this structure is important. This study was carried out to analyze the structure of carbody and evaluate safety under maximum vertical load, compressive load, and torsional load. Accordingly, stress tests were conducted on the carbody to measure the stress on each of their parts. Before the load test, a structural-analysis program was used for the stress distribution analysis of the body structure.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권5호
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• pp.344-350
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• 2004

This paper proposes the train control system for the LRT(light rail transit). With regard to information processing in car, we build a computer network in the car, turned the hardware required for train control into software, and developed the train control monitoring system(TCMS) and ATC. Drive type of train control system car can drive with driverless mode basically, and this paper applied special communication type for car control, data analysis, the propulsion efforts and breaking effort can control the cars. It is used vector control in propulsion control and proposed operating pattern for propulsion control thinking operating data of rubber tire LRT.