• 산업기술연구
• /
• 제26권B호
• /
• pp.11-20
• /
• 2006

LNG is a valuable fuel since it offers some environmental, energy security and economic benefits over diesel. It could be used mainly in heavy-duty trucks and buses. Car acceleration induces the slope angle of the liquid fuel in the tank. Slope angle changes the surface area wetted by liquid fuel and consequently heat leak to the tank. This research is a result of numerical simulation of the heat leak with the car acceleration to LNG tank. The "Pro-HeatLeak" Fortran program is developed and the verification test of the developed program is done. The difference between numerical results and calculated results from MathCad verification test is less than 0.07 percent. The smallest heat leak is correspond to the case without oscillation. For the high car acceleration the value of heat leak is greater than that for the small acceleration. The difference between maximum and minimum heat leak for 10 gallons of fuel vapor in the tank is about 10 percent.

• 응용통계연구
• /
• 제29권5호
• /
• pp.835-847
• /
• 2016

공간통계 방법 중 지역에 대한 어떤 집합체 자료나 평균자료들을 분석하는데 일반적으로 공간적 자기회귀(conditionally autoregressive) 모형을 사용한다. 공간적 자기회귀 모형에 정의되는 공간적 이웃 소지역들은 중점의 거리나 근접성으로 정의된다. Kyung과 Ghosh (2010)는 방향에 따라서 이웃간 자기상관성의 크기가 다른 공간적 확장 모형을 제시하였다. 제안된 방향적 조건부 자기회귀(directional conditionally autoregressive) 모형은 고유 이방성을 모형화하여 기존의 CAR과정을 일반화한다. 제시한 방향적 조건부 자기회귀모형의 최대우도 추정량의 특성에 대해 설명하였고, 스코틀랜드 그레이터 글래스고우의 로그변환된 부동산 가격에 적용하여 조건부 자기회귀모형과 비교하였다.

• 대한인간공학회지
• /
• 제32권4호
• /
• pp.381-387
• /
• 2013

Objective: This paper studies the method of measuring whole-body vibration in the car and terms associated. Background: Human exposure to vibration can be broadly classified as localized and whole-body vibration. The whole-body vibration affects the entire body of the exposed person. It is mainly transmitted through the seat surfaces, backrests, and through the floor to an individual sitting in the vehicle. It can affect the comfort, performance, and health of individuals. Method: Human responses to whole-body vibration can be evaluated by two main standards such as ISO 2631 and BS 6841. The vibration is measured at 8 axes - three translations at feet, 3 translations of hip and two translations of back proposed by Griffin. B&K's sensors used in this study are the 3-axes translational acceleration sensor to measure the translational accelerations at the hip, back and foot. Results: The parameters associated with the whole-body vibration in the car are frequency weightings, frequency weighted root-mean-square, vibration dose values, maximum transient vibration value, seat effective amplitude transmissibility, ride values and ride comfort. Conclusion: Studied the evaluating methods of vibration exposure and ride comfort. Application: Evaluation of whole-body vibration in the car.

• 한국철도학회논문집
• /
• 제10권1호
• /
• pp.39-44
• /
• 2007

This rafer explains a durability test of a large train car body made of carbon/epoxy composite material. The composite car body with the length of 23m was manufactured as a sandwich structure composed of an aluminum honeycomb core and CF1263 woven fabric carbon/epoxy faces. In order to evaluate durability of the composite car body, it was excited by two 500kN capacity hydraulic actuators installed underneath the body bolster. The natural frequency of the composite car body under full weight condition was found to be 4.33Hz. Based on this result, the excitation frequency and displacement of 5Hz and ${\pm}1.0mm$, respectively, were used as inputs for the durability test. The test was conducted for $2{\times}10^6$ cycles. During the test, the nondestructive tests using X-ray radiography and dye penetration method was performed to determine the presence of the cracks. Upon completion of the test, no cracks were found.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
• /
• pp.321-324
• /
• 2006

LMTT(Linear Motor based Transfer Technology) is a new type of transfer system used in the maritime container terminal for the port automation, and largely consists of a controller, shuttle car, and rail. The shuttle car is divided into the frame part, the driving part, and wheels. In order to design this system, various researches on each part of it must be conducted. In this study, we dealt with the optimum design for the mover of the shuttle car designed from previous studies on the strength of the frame with respect to the number of cross beams to minimize the weight of the shuttle car and to satisfy design criteria of cargo-handling systems in container terminal. For the optimization of the mover, thicknesses of each beam were adopted as design variables, the weight of the frame as objective function, and stress and deflection per unit length as constraint condition.

• Journal of information and communication convergence engineering
• /
• 제9권4호
• /
• pp.447-451
• /
• 2011

Recently, various in-vehicle networks have been developed respectively in order to accomplish their own purposes such as CAN and MOST. Especially, the MOST network is usually adapted to provide entertainment service. The car navigation system is also widely used for guiding driving paths to driver. The position for the navigation system is usually acquired by GPS technology. However, the GPS technique has two serious problems. The first is unavailability in urban canyons. The second is inherent positional error rate. The problems have been studied in many literatures. However, the second still leads to incorrect locational information in some area, especially parallel roads. This paper proposes a performance tuning method of image matching algorithm for the car navigation system. The method utilizes images obtained from in-vehicle MOST network and a real-time image matching algorithm which determines the direction of moving vehicle in parallel section of road. In order to accuracy improvement of image matching algorithm, three conditions are applied. The experimental tests show that the proposed system increases the accuracy.

• 대한안전경영과학회지
• /
• 제14권4호
• /
• pp.93-105
• /
• 2012

The purpose of this study was to investigate drivers' postures in different car pedal systems and skilled levels under fatigue. Twenty four subjects participated in this experiment. For three-dimensional analyses, six cameras (Proreflex MCU-240, Qualisys) were used to acquire raw data. The parameters were calculated and analyzed with Visual-3D. In conclusion, ROAs of two leg-pedal system were less than one leg pedal system by pattern analysis. Through statistical tests, skilled levels have effects on ROAs(X, Y, Z) of ankle joint at breaking a pedal and ROAs(Y, Z) of ankle joint at accelerating a pedal. Also, car pedal systems have effects on ROAs(Y, Z) of ankle joint, and ROA(Z) of knee joint at accelerating a pedal. In addition, skilled levels and car pedal systems (cross effects) have an effect on ROA(Z) of ankle joint. These findings suggested that we should improve a present single pedal system.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2014년도 추계학술대회
• /
• pp.115-117
• /
• 2014

최근 들어, 사람들의 삶의 질을 향상시키기 위해 유비쿼터스 기술을 활용한 서비스들이 다양하게 제공되고 있다. 다양한 서비스 중에서도 특히 교통분야에서는 유비쿼터스 기술 활용이 두드러지게 이루어지고 있는 분야이다. 본 연구에서는 유비쿼터스 기술을 활용한 교통 서비스 중에서도 차량 추적 관리 서비스에 관련하여 비즈니스 모델과 비즈니스 프로세스를 파악하고자 한다. 이를 위해 차량 추적 관리서비스에 대한 정의를 살펴보고 난 후 이를 기반으로 비즈니스 모델을 도출하기 위한 세부 추적관리 서비스를 파악하였다. 연구 결과, 차량 추적관리 서비스에서 2개의 대표 서비스를 도출하였고 도출된 세부 서비스의 이해관계자, 수익자, 수익가치 모델을 도출하여 유비쿼터스를 활용한 U-차량추적관리 서비스의 비즈니스 모델을 파악하였다.

• 한국멀티미디어학회논문지
• /
• 제24권1호
• /
• pp.146-154
• /
• 2021

Conspicuous consumption is often investigated in Korea and consumers purchase a product to publicly display economic power or social status. The existing studies argue that brand loyalty and luxury brand preferences escalate conspicuous consumption, and it is important to identify different visual perception to understand irrational consumers' behavior. Car emblem as brands' visual identity represents the brand's image, mission and message. Irrational consumers thus are expected have different visual perception to the emblem or logo. To understand the impact of irrational consumer behavior on visual perception, this study explored how brand loyalty and luxury brand preferences impact on the visual perception of car emblems between Korean domestic brand and imported brand. This study used eye tracking technology to measure the respondents' attention on an emblem of the cars. Eye tracking tools analyze fixations and measure the attention on a specific area of interests (AOI). This study explored the maintaining time and frequency on AOI, as well as explored the size of pupil to identify the respondents' attention on the AOI. In this experiment, the logos of domestic cars (i.e., Hyundai and Kia) and foreign cars (i.e., Mercedes-Benz and BMW) were swapped to see how irrational consumer behavior impact on visual perception of car emblem.

• 한국인공지능학회지
• /
• 제9권1호
• /
• pp.9-14
• /
• 2021

This paper predicted a model that indicates whether to buy a car based on primary health insurance customer data. Currently, automobiles are being used to land transportation and living, and the scope of use and equipment is expanding. This rapid increase in automobiles has caused automobile insurance to emerge as an essential business target for insurance companies. Therefore, if the car insurance sales are predicted and sold using the information of existing health insurance customers, it can generate continuous profits in the insurance company's operating performance. Therefore, this paper aims to analyze existing customer characteristics and implement a predictive model to activate advertisements for customers interested in such auto insurance. The goal of this study is to maximize the profits of insurance companies by devising communication strategies that can optimize business models and profits for customers. This study was conducted through the Microsoft Azure program, and an automobile insurance purchase prediction model was implemented using Health Insurance Cross-sell Prediction data. The program algorithm uses Two-Class Logistic Regression and Two-Class Boosted Decision Tree at the same time to compare two models and predict and compare the results. According to the results of this study, when the Threshold is 0.3, the AUC is 0.837, and the accuracy is 0.833, which has high accuracy. Therefore, the result was that customers with health insurance could induce a positive reaction to auto insurance purchases.