• Journal of the Korea Safety Management & Science
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• v.9 no.2
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• pp.149-159
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• 2007

This paper is to propose two computation procedures of reliability measures for large interval data. First method is efficient to verify the relationship among four reliability measures such as F(t), R(t), f(t) and $\lambda(t)$. Another method is effective to interpret the concept of various reliability measures. This study is also to reinterpret and recompute the errors of four reliability measures discovered in the reliability textbooks. Various numerical examples are presented to illustrate the application of two proposed procedures.

• Journal of the Korean Society for Railway
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• v.4 no.1
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• pp.40-56
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• 2001

지난해 6.15 남북공동선언을 계기로 남북간의 교류와 협력의 분위기가 조성되고 남북정상회담의 가시적 성과의 하나로 이산가족상봉과 남북철도 연결사업이 시작되어 경의선의 남쪽구간은 상당한 공사진척도를 보이고 있다. 그러나 최근의 상황은 북쪽은 아직 공사조차 시작하지 않고 있는 입장이다. 그러나 이와는 별도로 남북철도의 연결과 이의 대륙철도와의 연결은 '철의 실크로드' 구성과 함께 시베리아횡단철도(TSR)의 이용이 그간의 논의 수준을 넘어 구체화 되었다. 게다가 수교이후 러시아가 가장 적극적으로 접근하고 있는 시베리아횡단철도(TSR)의 활성화 논의는 남북관계가 한러관계 나아가 남·북·러 삼각협력의 복잡한 구도 속에서 논의되고 있는 현실이다. (중략)

• Journal of Korean Society of Transportation
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• v.20 no.4
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• pp.213-222
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• 2002

교통사고가 중요한 사회 문제로 대두되어 정부는 교통안전대책의 실질적인 추진 방안으로 "교통사고 잦은 곳"과 "위험도로" 개선사업을 제시·시행하고 있다. 이에 "교통사고 잦은 곳" 개선사업은 추진현황에 따라 각 년도별 기본 개선계획의 평가 및 경제적 타당성에 대한 효과분석이 이루어지고 있다. "위험도로"'의 경우 모든 사업을 건설교통부 산하 국도유지사무소에서 진행을 하고 있으나, 광범위한 사업으로 인한 업무과중 및 개선사업비 조달 등의 문제로 개선된 현황의 체계적인 효과분석이 이루어지지 못하고 있는 실정이다. 이에 따라 본 연구에서는 "위험도로" 개선사업에 대한 효과분석을 수행하여 보다 비용-효율적인 개선사업이 될 수 있는 기반을 마련하고자 한다. 이를 위해 전체 위험도로 구간 중에서 '광주국도유지사무소' 및 '순천국도유지사무소' 관할 구역 내의 "위험도로"로 선정(1995년)된 도로구간 중 1999년 이전에 도로개선공사가 완료된 후 현재 교통소통이 원활하게 진행되는 18개 도로구간을 연구 대상으로 선택하였다. 선택되어진 18개 구간에 대한 도로개선공사 전후의 교통사고건수 및 교통사고율을 효과척도로 삼고 각 사고에 대한 소요비용을 기준으로 경제성 평가를 실시하였다. 이를 근거로 "위험도로" 개선사업에 대한 타당성조사 및 효과분석을 실시한 결과 "위험도로" 개선사업의 타당성이 입증되었다. 연구 분석결과가 전라도 권역의 사업을 중심으로 진행되어져 전국적인 개선사업에 대한 대표성을 가지고 있다고 볼 수는 없으나, 체계적인 분석을 통한 개선사업의 효과를 구체화 할 수 있는 대안을 제시할 수 있을 것으로 사료된다. 더불어 공사 완료된 도로구간에 대한 상세한 공사비 내역과 다수의 개선방안별 자료가 갖추어지면 위험도로의 사고율과 개선방안별 상관관계를 관련 비용을 중심으로 도출함으로서 비용-효율적인 개선 방안을 제시할 수 있을 것이다. 또한 비용-효율적인 개선 방안을 기반으로 한 각각의 사업 투자우선 순위 결정방안에 관한 지속적 인 연구가 요망된다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.3
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• pp.39-49
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• 2017

Standards suitable for local conditions on deciding one-way road are desperately required to solve traffic congestions at the backside roads in the old downtown areas which were not designated as a road by urban planning. Therefore, this study intends to re-establish a standard to decide one-way road which is regarded to be of the greatest effect among traffic system control methods in order to control one-way road system more efficiently. Also, this paper suggests a standard for such decision to improve efficiency of using backside roads and expand designation of one-way road. AHP (analytic hierarchy process) was carried out among the traffic experts to find out the factors to decide one-way road system. Its result reveals that importance of causing accident to walking quantity and traffic was high. 10,000 cases out of all the possible scenarios of accident by combining detailed evaluation items and scales were extracted to draw the outcomes of analyzing the scenarios, which were schematized in a graph. As a result, division by three sections of point of inflection was verified into $1{\leq}$ section A<1.91, 1.9$1{\leq}$ section B<2.08, and $2.08{\leq}$ section C<3. In other words, priority of deciding one-way road should be given to section C, the highest total point, while posterior to section A, where relatively low points are distributed. The standard on deciding one-way road suggested in this paper may be used for designating one-way road and basic data to re-establish the relevant system in the future.

• Journal of Korea Society of Industrial Information Systems
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• v.20 no.3
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• pp.61-69
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• 2015

This study presents a probabilistic knowledge discovery method to interpret heart rate variability (HRV) based on time and frequency domain indexes, extracted using discrete wavelet transform. The knowledge induction algorithm was composed of two phases: rule generation and rule estimation. Firstly, a rule generation converts numerical attributes to intervals using ROC curve analysis and constructs a reduced ruleset by comparing consistency degree between attribute-value pairs with different decision values. Then, we estimated three measures such as rule support, confidence, and coverage to a probabilistic interpretation for each rule. To show the effectiveness of proposed model, we evaluated the statistical discriminant power of five rules (3 for atrial fibrillation, 1 for normal sinus rhythm, and 1 for both atrial fibrillation and normal sinus rhythm) generated using a data (n=58) collected from 1 channel wireless holter electrocardiogram (ECG), i.e., HeartCall$^{(R)}$, U-Heart Inc. The experimental result showed the performance of approximately 0.93 (93%) in terms of accuracy, sensitivity, specificity, and AUC measures, respectively.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.1 no.1
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• pp.58-69
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• 2002

Most of the traffic accidents are a rear-end collision and a clash generated in the signalized intersection on the local roads. So, it is demanded that the high-quality of signal control and dilemma zone control. According to the cases generated by foreign countries, we established the strategies which are composed of Volume-Density Control, strategy of the dilemma zone control using R-detector (microwave detector) In Japan and EC-DC Control. MOEs(Measure of effectiveness) are car numbers in the dilemma zone , max-out probability in the safe side and the average stopping delay in the progress side. We choose a signalized intersection in rural highway to analyze the effect of the strategies and practiced an on-the-spot survey. The result of the survey is applied to the basic data in the simulator. Consequently, strategy of the dilemma zone control using R-detector(microwave detector) in Japan is the best effective in the safe side and EC-DC control is the best in the progress side. Based on the result, we developed the effective strategy of the signal control . This strategy is composed of the strategy of Japan and the detector on the stopping line used in the EC-DC control. On the result of the analysis, new strategy is the best effective in two sides.

• Journal of the Institute of Convergence Signal Processing
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• v.4 no.2
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• pp.18-24
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• 2003

One of the most important subjects in the implementation of real time speech recognizer is to design both reliable VAD(Voice Activity Detection) and suitable speech feature vector. But, because it is difficult to calculate reliable VAD in the environment having surrounding noise, designed suitable speech feature vector may not be obtained. Solving this problem, in this paper, we implement not only short time power spectrum which is generally used but also two additive parameters, the comparison measure of spectrum density having robust property in noise and linear discriminant function using linear regression, then perform VAD by using the combination of each parameter having apt weight in other magnitudes of surrounding noise and confirm that proposed parameters show a robust characteristic in circumstances having surrounding noise by using DTW(Dynamic Time Waning) in recognition experiment.

• Journal of Korean Society of Transportation
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• v.18 no.2
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• pp.17-26
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• 2000

LOS(Level of Service), the qualitative measure describing operational condition of highway, must be evaluated as quantative index in terms of user service. So, This study is focused on developing the user cost function that user cost is measured in the variation of V/C, MOE(Measure of Effectiveness) of LOS in basic Section of highway. The user cost is calculated as the sum of accident cost, operation cost, travel time cost. The data is collected in the four basic section of Singal-Ansan and Jung bu Highway. As the result of user cost function analysis, the user cost is the lowest When V/C is 0.54. Considering the V/C ratio(0.7) of Basic Section in rural highway suggested in KHCM, We find out that the LOS suggested KHCM increase the user cost of highway.

• Journal of Korean Society of Transportation
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• v.32 no.2
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• pp.119-129
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• 2014

This study aims to evaluate the accident reduction effects of 'Section Speed Enforcement System' (SSES) operation in freeways. In pursuing the above, this study collects the accident data for 5 years (2 years before operation and 3 years after operation) at all 9 sections where SSESs are operated, and evaluates annually the effects before and after operation using the comparison group method (C.G. Method). The measures of effectiveness are total accidents (TAs), fatal and serious accidents (FSAs), total injuries (TIs) and fatal and serious injuries (FSIs). The main results are as follows. First, TAs and TIs are reduced to 41.7 and 17.1%, respectively. Second, FSAs and FSIs are reduced to 41.7 and 32.2%, respectively. Therefore, SSES has more effectiveness at fatal and serious accident. Third, the accident reduction effect has been increasing, and particularly the effect of 'after three years' is evaluated to be notable.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.3
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• pp.73-84
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• 2010

This study presents a novel method to identify hazardous segments of freeway using global positioning system(GPS) based probe vehicle data. A variety of candidate contributing factors leading to higher potential of accident occurrence were extracted from the probe vehicle dataset. The research problem was defined as a classification problem, then a well-known classifier, bayesian neural network was adopted to solve the problem. A binary logistic regression technique was also used for selecting salient input variables. Test results showed that the proposed method is promising in extracting hazardous freeway sections. The outcome of this study will be effectively used for evaluating the safety of freeway sections and deriving countermeasures to prevent accidents.