• 자동차안전학회지
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• 제4권1호
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• pp.5-11
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• 2012

This paper discusses the evaluation of the safety impact of the Adaptive Cruise Control (ACC) system in Korea. To evaluate the safety impact, this paper suggests an analysis method by using the test scenario and field operational test data. The test scenario is composed to represent the main component factor of the ACC system and ACC related accident situation such as rear-end collision, lane-change, and road-curvature, etc. Also, from the field operation test data, the system's potential to increase the safety can be measured ideally. Besides, field operational testdata was used to revise the expected safety impact value as Korean road conditions. By using the proposed evaluation method, enhanced safety impact of the ACC system can be estimated scientifically.

• 제어로봇시스템학회논문지
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• 제21권7호
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• pp.699-708
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• 2015

In the testing of a software component-based robot system, generating test cases for the system is a time-consuming and difficult task that requires the combining of test data. This paper proposes an adaptive combinatorial testing method which is based on the input/output relationship among components and which automatically generates the test cases for the system. The proposed algorithm first generates an input/output relationship graph in order to analyze the input/output relationship of the system. It then generates the reduced set of test cases according to the analyzed type of input/output relationship. To validate the proposed algorithm some comparisons are given in terms of the time complexity and the number of test cases.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.347-349
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• 2014

Model verification and validation (V&V) is a current research topic to build computational models with high predictive capability by addressing the general concepts, processes and statistical techniques. The hypothesis test for validity check is one of the model validation techniques and gives a guideline to evaluate the validity of a computational model when limited experimental data only exist due to restricted test resources (e.g., time and budget). The hypothesis test for validity check mainly employ Type I error, the risk of rejecting the valid computational model, for the validity evaluation since quantification of Type II error is not feasible for model validation. However, Type II error, the risk of accepting invalid computational model, should be importantly considered for an engineered products having high risk on predicted results. This paper proposes a technique named as the response-adaptive experimental design to reduce Type II error by adaptively designing experimental conditions for the validation experiment. A tire tread block problem and a numerical example are employed to show the effectiveness of the response-adaptive experimental design for the validity evaluation.

• 드라이브 ㆍ 컨트롤
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• 제14권3호
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• pp.8-17
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• 2017

With automobiles sharply increasing in numbers worldwide, we are faced with critical social issues such as traffic accidents, traffic jams, environmental pollution, and economic inefficiency. In response, research on ITS is promoted mainly by regions with advanced automotive industry such as the U.S., Europe, and Japan. While Korea is working on moving forward in the global market through developing and turning to global standards systems related to ASV (Advanced Safety Vehicle), the country is not fully prepared for such projects. The purpose of ACC (Adaptive Cruise Control) is to control a vehicle's longitudinal speed and distance and minimize driver workload. Such a system should be valuable in preventing accidents, as it reduces driver workload in the 21st-century world of telematics created by development of the automobile culture industry. In this light, the thesis presents a method to test and evaluate ACC system and a mathematical method to assess distance. For the proposed test and evaluation, theoretical values are tested with vehicle test and a database is acquired, by using vehicles equipped with an ACC system. Theoretical evaluation criteria for developing ACC system may be used and scenario-specific evaluation methods may find useful application through testing the formula proposed by comparing the database and mathematical method.

• 한국전문물리치료학회지
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• 제26권3호
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• pp.106-114
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• 2019

Background: It is difficult to assess whether community-dwelling frail older adults may remain pre-frail status or improve into a robust state without being directly checked by health care professionals. The health information perceived by older adults is considered to be one of best sources of potential concerns in older adult population. An online measurement system combined with item response theory (IRT) and computer adaptive testing (CAT) methods is likely to become a realistic approach to remotely monitor physical activity status of frail older adults. Objects: This article suggests an approach to provide a precise and efficient means of measuring physical activity levels of community-dwelling frail older adults. Methods: Article reviews were reviewed and summarized. Results: In comparison to the classical test theory (CTT), the IRT method is empirically aimed to focus on the psychometric properties of individual test items in lieu of the test as a whole. These properties allow creating a large item pool that can capture the broad range of physical activity levels. The CAT method administers test items by an algorithm that select items matched to the physical activity levels of the older adults. Conclusion: An online measurement system combined with these two methods would allow adequate physical activity measurement that may be useful to remotely monitor the activity level of community-dwelling frail older adults.

• Asia Marketing Journal
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• 제15권2호
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• pp.175-194
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• 2013

The purpose of this study is to investigate the effects of the locomotion orientation on salespeople' sales performance with the mediating effect of selling behavior(adaptive selling behavior, SOCO). And we figure out the relationship between customer-oriented selling behavior and adaptive selling behavior because those relationships are not clear. The authors infer research hypotheses based on literature review. We have confirmed the reliability and validity test and those results can be acceptable. Hypotheses test were conducted with structural equation modeling, AMOS. All paths in the research model reasoned by authors have been supported statistically at the significant level. This study with the theoretical implications is as follows. First, this study is the first attempt to investigate the path between locomotion orientation and adaptive selling behavior and SOCO. Secondly, there is an empirical conflict between our study and Franke and Park(2006)'s study. Our study was contradictory to Franke and Park(2006)'s consequences. And so, figuring out clearly those causal paths remains. This study with practical implications are as follows. First of all, the salespeople' selling performance was affected by adaptive selling behavior, customer-oriented selling behavior, and sales-oriented activities, such as the importance of selling behavior once again proven. It is necessary to enhance the capabilities that can be transformed into action appropriate to the needs of customers each sales step-by-step in the process of salespeople for various system through education and incentives, and to interact with customers and understand their customers relative to salespeople will. In order to enhance adaptive selling behavior, the company needs to do educational program and monitoring system with the positional promotion when salespeople get the high adaptive selling behavior. Secondly, the locomotion orientation of the salespeople is to cause this selling behavior. Management style to increase locomotion orientation is needed, which means, salespeople' superior about something should be conducted. In order to stimulate the selling behavior of the salespeople, most supervisors should use some managerial tools such as feedback, engagement, and rewards.

• 응용통계연구
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• 제34권2호
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• pp.205-223
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• 2021

본 논문에서는 adaptive lasso 방법을 이용하여 단위근의 존재 여부를 판단하는 방법에 대해 연구하였다. 최근 원 시계열에 상수항과 선형 추세가 포함된 ADF-회귀모형식을 adaptive lasso로 추정하여 단위근을 식별하는 방법이 제안되었으나, 미지의 선형 추세가 존재할 때 검정력이 떨어지는 것으로 나타났다. 이 문제를 해결하기 위해 본 논문에서는 ADF-회귀모형식을 적합시킬 때 원 시계열 대신 선형 추세가 제거된 시계열을 사용하는 수정안을 제안하였다. 그리고 수정안에서는 일차적으로 선형 추세를 제거한 후 모형식을 적합시키기 때문에 ADF-회귀모형식 중 상수항과 선형 추세를 모두 포함하지 않는 모형식을 사용하였다. 기존의 방법보다 수정안을 사용할 때 단위근의 존재를 판단하는 검정력이 향상되는지 모의실험을 통해 검토하였으며, ADF 검정과 DF-GLS 검정과의 비교 실험도 진행하였다. 모의실험 결과 adaptive lasso를 이용하여 단위근의 존재를 판단할 때 원 시계열보다 추세가 제거된 시계열을 사용하는 경우가 높은 정확도를 가지며, 자료의 개수가 충분히 많을 때 단위근을 잘 판단함을 확인할 수 있었다.

• 한국정보과학회논문지:소프트웨어및응용
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• 제32권5호
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• pp.438-448
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• 2005

본 논문에서는 학습자들의 학습 특성 및 학습 능력에 따라 학습내용을 동적으로 구성하여 제공하는 적응형 교수 시스템을 제안한다. 본 논문에서 제안한 시스템은 학습 단계와 평가 단계를 연계함으로써 평가 단계에서 추정된 학습자의 능력에 따라 차기 학습 단계에서 수준별 학습내용을 동적으로 구성하여 학습자에게 제공함으로서 개인화된 교수${\cdot}$학습을 지원하고 있다. 이를 위해 먼저 학습자들의 학습 능력을 정확하게 평가할 수 있도록 문항반응이론에 의한 컴퓨터 적응적 평가를 이용하여 평가 단계를 구현하였으며, 또한 추정된 각 학습자의 능력 수준에 맞는 학습내용을 제공하기 위해 퍼지 개념을 이용하여 퍼지 수준 집합을 구성한 후 제공함으로써 학습자에 따른 수준별 학습이 가능하도록 학습 단계를 구현하였다.

• Journal of Mechanical Science and Technology
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• 제14권1호
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• pp.103-112
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• 2000

Numerical simulations of unsteady opposed-flow flames are performed using an adaptive time integration method designed for differential-algebraic systems. The compressibility effect is considered in deriving the system of equations, such that the numerical difficulties associated with a high-index system are alleviated. The numerical method is implemented for systems with detailed chemical mechanisms and transport properties by utilizing the Chemkin software. Two test simulations are performeds hydrogen/air diffusion flames with an oscillatory strain rate and transient ignition of methane against heated air. Both results show that the rapid transient behavior is successfully captured by the numerical method.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.636-639
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• 1997

In this paper, a dynamic control scheme is proposed which not only compensates for the lateral dynamics and longitudinal dynamics but also deal with the yaw motion dynamics. Using the dynamic control technique, adaptive and learning algorithm together, the proposed controller is not only robust to disturbance and parameter uncertainties but also can learn the inverse dynamics model in steady state. Based on the proposed dynamic control scheme, a dynamic vehicle simulator is contructed to design and test various control techniques for 4-wheel steering vehicles.