• 동력기계공학회지
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• 제7권3호
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• pp.61-68
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• 2003

Steering characteristics is an important factor in the evaluation of vehicle quality. To estimate steering characteristics in the vehicle conceptual design stage, vehicle dynamics simulation methods are very efficient. However, it is often difficult to simulate vehicle dynamics for the specific driving scenarios in open-loop driving environment. An efficient driver-in-the-loop vehicle model will be efficient for this job. A good tire model is also very important for the accurate vehicle dynamics simulation. In this research, a driver model is used to simulate vehicle steering dynamics for a 8-dof vehicle model with STI(Systems Technology, Inc.) tire model. For the demonstration of this model, a SUV(sports utility vehicle) and a sedan were simulated.

• 디자인학연구
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• 제17권3호
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• pp.449-460
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• 2004

최근에 스포츠유틸리티 차량이 점차 대중화되고 있다. 이것은 과거의 단순한 승용차 중심의 자동차 소비구조에서 보다 다양화 된 생활양식에 따라 보다 전문화 된 성능의 차량에 대한 수요가 늘어난 이유에서 인 것으로 보인다. 이러한 수요변화는 주 5일 근무에 의한 여가시간의 증가와 생활수준 향상에 따른 레저활동의 요구 증가 등도 원인이지만, 차량 자체의 성능향상과 차종 다양화 역시 중요한 요인으로 작용하고 있다. 자동차 발전의 역사 초기부터 다양한 유형의 다목적 차량들이 개발되고 사용되어오고 여는데, 이들은 미국의 $\ulcorner$지프$\lrcorner$에서 발전된 차량이 주류를 이루고 있다. 이 차량들은 여러 메이커들을 통해 각각의 기능적 전문성을 살린 다양한 정통적 유형과 복합개념의 차량들로 개발되고 있다. 복합개념의 차량들은 전반적으로 소형화를 추구하는 반면, 정통적 형태의 4륜 구동차량들은 대형화 및 고성능화 되는 양방향의 경향이 동시에 나타나고 있다. 향후에 이러한 경향은 다양한 메이커와 차종에서 확대되어 나타나게 될 것으로 예측된다.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 2006년도 제28회 동계학술발표회 논문집
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• pp.264-297
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• 2006

In this paper, we attempt to analyze consumer preference for the alternative-fuel vehicles based on data from a stated preference using the conjoint analysis. Five possible fuel types (gasoline, diesel, CNG, LPG, Hybrid (electricity+gasoline)) are covered in conjoint cards. To estimate and analyze consumer preference, discrete choice model is used. Specifically, Bayesian mixed logit model is used. Based on estimating results, we discuss the business strategy and policy for the alternative fuel vehicle.

• 대한교통학회:학술대회논문집
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• 대한교통학회 2000년도 제37회 학술발표회논문집
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• pp.25-47
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• 2000

In route guidance systems fastest-path routing has typically been adopted because of its simplicity. However, empirical studies on route choice behavior have shown that drivers use numerous criteria in choosing a route. The objective of this study is to develop computationally efficient algorithms for identifying a manageable subset of the nondominated (i.e. Pareto optimal) paths for real-time vehicle routing which reflect the drivers' preferences and route choice behaviors. We propose two pruning algorithms that reduce the search area based on a context-dependent linear utility function and thus reduce the computation time. The basic notion of the proposed approach is that ⅰ) enumerating all nondominated paths is computationally too expensive, ⅱ) obtaining a stable mathematical representation of the drivers' utility function is theoretically difficult and impractical, and ⅲ) obtaining optimal path given a nonlinear utility function is a NP-hard problem. Consequently, a heuristic two-stage strategy which identifies multiple routes and then select the near-optimal path may be effective and practical. As the first stage, we utilize the relaxation based pruning technique based on an entropy model to recognize and discard most of the nondominated paths that do not reflect the drivers' preference and/or the context-dependency of the preference. In addition, to make sure that paths identified are dissimilar in terms of links used, the number of shared links between routes is limited. We test the proposed algorithms in a large real-life traffic network and show that the algorithms reduce CPU time significantly compared with conventional multi-criteria shortest path algorithms while the attributes of the routes identified reflect drivers' preferences and generic route choice behaviors well.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.141-146
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• 2007

A gear whine sound due to the axle system is one of the most important sound qualities in a sport utility vehicle (SUV). In the previous research about the gear whine sound, it was known that it is difficult to evaluate the gear whine sound objectively by using the only A-weighted sound pressure level because of the masking effect. In this paper, for the objective evaluation of the axle-gear whine sound, the characteristics of the axle-gear whine sound is at the first investigated based on the synthetic sound technology and the new objective evaluation method for the axle-gear whine sound is developed by using the sound metrics, which is the psychoacoustics parameters, and the artificial neural network (ANN) used for the modeling of the correlation between objective evaluation and subjective evaluation.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.671-675
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• 2001

Elastomers, which are engine mounts and body mounting rubbers, are traditionally designed for NVH use in vehicles, and they are designed to isolate specific unwanted frequencies. According to the measurement of the characteristics of engine mounts and body mounting rubbers, dynamic stiffness changes with respect to the driving miles accumulated in engine mounts and initial load in body mounting. This study looks at the variability in same engine mount properties, and the desired dynamic stiffness may increased with driving miles accumulated. And the dynamic stiffness of body mounting rubber changes very stiff above 150Hz.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.803-811
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• 2014

The moment when Electrical Vehicle (EV) starts charging or discharging is one of the most important parameters in estimating the impact of EV load on the grid. In this paper, a decision-making problem of determining the start time of charging and discharging during allowed period is proposed and studied under the uncertainty of real-time price. Prospect theory is utilized in the decision-making problem of this paper for it describes a kind of decision making behaviors under uncertainty. The case study uses the parameters of Springo SGM7001EV and adopts the historical realtime locational marginal pricing (LMP) data of PJM market for scenario reduction. Prospect values are calculated for every possible start time in the allowed charging or discharging period. By comparing the calculated prospect values, the optimal decisions are obtained accordingly and the results are compared with those based on Expected Utility Theory. Results show that with different initial State-of-Charge ($SoC_0$) and different reference points, the optimal start time of charging can be the one between 12 a.m. to 3 a.m. and optimal discharging starts at 2 p.m. or 3p.m. Moreover, the decision results of Prospect Theory may differ from that of the Expected Utility Theory with the reference points changing.

• 한국의류학회지
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• 제46권6호
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• pp.1128-1141
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• 2022

Due to increased interest in safety in sports, leisure, industries, and daily life; the demand for products that protect the head is increasing. As a preparatory study for the development of head protection for head injury prevention, this study analyzed patents and utility models related to head protection products such as industrial safety helmets, vehicle helmets, and sports protection gear. For this study, 368 patents and utility models for head protection products searched through WipsOn were selected and analyzed by application year, function, application, protection area, main material, and subject. From the analytic results of this study, the quantitative and qualitative flow and characteristics of developing technology related to head protection products were identified. Through the trend of current technology, it provided data to seek the development direction in the future. The significance of this study is to secure objective data to establish a road map for creating new Intellectual Property for head protection products.

• 한국자동차공학회논문집
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• 제16권4호
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• pp.8-13
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• 2008

Since hundreds thousands of pedestrians are killed or injured in car accidents every year, a variety of research efforts have been performed to protect pedestrians in pedestrian-vehicle crashes. The IHRA reports that injuries on the child head, the adult head, and the adult lower leg/knee are the most critical in the crashes. Identifying the current status of international activities on pedestrian protection, this study, in particular, carries out headform impact test using selected domestic vehicles categorized by three groups - Sedan, SUV (Sport Utility Vehicle), and 1 Box (One Box) Vehicle. According to the valuable findings from the test results, this paper proposes a methodology under which the Korean Technical Regulation for protecting pedestrians in pedestrian-vehicle crashes will be developed.

• 자동차안전학회지
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• 제6권2호
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• pp.12-17
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• 2014

The number of vehicle accidents related to the side impact has increased since 1990 in Korea, thus the side impact test has been performed as one of the major vehicle evaluations of the Korean New Car Assessment Program(KNCAP) in 2003. A total of 77 vehicles of eight different types(compact, small, semi-midsize, midsize, and large sedans and small, midsize, and large sports utility vehicles) were tested in side impact and side pole impact conditions. In this study, the head and thorax injury values(HICs and chest deflections) of the side impact tests performed between 2003 and 2013 were investigated in terms of vehicle type, test year, and test condition. The recent vehicles showed better safety performances(lower injury values) and similar injury patterns were obtained between side impact and pole side impact tests.