PURPOSES : This study compared two measures of traffic flow effectiveness on roads with roundabouts and signalized intersections and determined the more appropriate measure. METHODS: In addition to average delay time, the conventionally used measure, average travel time was introduced to measure traffic flow effectiveness because it is able to be obtained through field survey and reflect different travel distances and speed limits of roundabouts and signalized intersections. Using the two measures, roundabouts and signalized intersections were compared through simulations in terms of traffic flow effectiveness. RESULTS : For one-way single-lane roads, the two measures indicated consistent results that roundabouts were more effective than were signalized intersections when the traffic volume was less than 300 vphpl but vice versa when it exceeded 450 vphpl; however, the measures yielded inconsistent results when the volume was 350~400 vphpl. For one-way double-lane roads, the two measures indicated consistent results that roundabouts were more effective than were signalized intersections when the volume was less than 200 vphpl but vice versa when it exceeded 400 vphpl; however, the measures yielded inconsistent results when the volume was 250~350 vphpl. The results obtained using the two measures differed substantially for double-lane roads because behaviors such as weaving and lane changing at roundabouts are more common in double-lane roads than in single-lane roads. CONCLUSIONS : The average delay time would be lower on roads with roundabouts, but average travel time would be lower on roads with signalized intersections. Thus, evaluating the relative effectiveness of roads with roundabouts and signalized intersections by using average delay time alone would be inappropriate, whereas using average travel time as the evaluation index would yield fairer results.

PURPOSES : The purposes of this study are to compare the day and night characteristics and to develop the models of traffic accidents. in Rural Signalized Intersections METHODS : To develop day and night traffic accident models using the Negative Binomial Model, which was constructed for 156 signalized intersections of rural areas, through field investigations and casualty data from the National Police Agency. RESULTS : Among a total of 17 variances, the daytime traffic accident estimate models identified a total of 9 influence factors of traffic accidents. In the case of nighttime traffic accident models, 11 influence factors of traffic accidents were identified. CONCLUSIONS: By comparing the two models, it was determined that the number of main roads was an independent factor for daytime accidents. For nighttime accidents, several factors were independently involved, including the number of entrances to sub-roads, whether left turn lanes existed in major roads, the distances of pedestrian crossings to main roads and sub-roads, lighting facilities, and others. It was apparent that if the same situation arises, the probability of an accident occurring at night is higher than during the day because the speed of travel through intersections in rural areas is somewhat higher at night than during the day.

PURPOSES : The control delay in seconds per vehicle is the most important traffic operational index to evaluate the level of service of signalized intersections. Thus, it is very critical to calculate accurate control delay because it is used as a basic quantitative evidence for decision makings regarding to investments on traffic facilities. The control delay consists of time-in-queue delay, acceleration delay, and deceleration delay so that it is technically difficult to directly measure it from fields. Thus, diverse analysis tools, including CORSIM, SYNCHRO, T7F, VISTRO, etc. have been utilized so far. However, each analysis tool may use a unique methodology in calculating control delays. Therefore, the estimated values of control delays may be different by the selection of an analysis tool, which has provided difficulties to traffic engineers in making solid judgments. METHODS: This study was initiated to verify the feasibility of diverse analysis tools, including HCM methodology, CORSIM, SYNCHRO, T7F, VISTRO, in calculating control delays by comparing estimated control delays with that measured from a field. RESULTS : As a result, the selected tools produced quite different values of control delay. In addition, the control delay value estimated using a calibrated CORSIM model was closest to that measured from the field. CONCLUSIONS: First, through the in-depth experiment, it was explicitly verified that the estimated values of control delay may depend on the selection of an analysis tool. Second, among the diverse tools, the value of control delay estimated using the calibrated microscopic traffic simulation model was most close to that measured from the field. Conclusively, analysts should take into account the variability of control delay values according to the selection of a tool in the case of signalized intersection analysis.

PURPOSES : The present paper is to compare vehicles' CO2 emissions in roundabouts and signalized intersections. METHODS : The present paper uses the SIDRA software with variables of traffic and road conditions. RESULTS : The results of the study are as follows : First, when entering traffic volumes are more than 1600pcph, vehicle's CO2 emissions in roundabouts are lower than those of signalized intersections regardless of the left turn ratio. Second, When entering traffic volumes are more than 2800pcph, vehicles's CO2 emissions in 2-lane approaches are lower than those of 1-lane approaches in signalized intersection. Third, when entering traffic volumes are more than 1600pcph, vehicle's CO2 emissions of CASE B are lowest. (CASE B is the condition with one exclusive left-turn lane and one exclusive straight lane and one shared straight lane with right-turn.) Also, CASE A is the condition that vehicle's CO2 emissions in roundabouts are lower than those of signalized intersections between 1600pcph and 3600pcph. (CASE A is the condition with one exclusive left-turn lane and one shared straight lane with right-turn.) But, when entering traffic volumes are more than 4000pcph, vehicle's CO2 emissions in signalized intersections is lower than those of roundabouts. CONCLUSIONS : It may be concluded that vehicle's CO2 emissions on roundabouts are much lower than those of signalized intersections, especially, when entering traffics volumes are between 1600pcph and 3600pcph in 1-lane or 2-lane approaches.

PURPOSES: Though the situation that the roundabouts are actively constructed, researches on the effect of the roundabouts focus mainly on the analysis of the expected effects of using only traffic simulation on the operation. Considering such problems, this study is conducted to analyze the effects of the various aspects based on field observation studies. METHODS: This study evaluated and analyzed the effects from the aspects of traffic operation, traffic safety, and traffic behavior by performing field observation studies with six roundabouts with/without signal controls on the pilot project areas for the roundabouts installed in 2010. RESULTS: Through the study results, it was found that the average travel time decreases by 14.7% and 2.4% on the signalized intersections and unsignalized intersections, respectively. The average travel speed increases by 9.7 and 5.8km/h on the roundabouts with/without signal lights. Regarding traffic safety, the speed deviation among individual vehicles decreases by approximately 18.4 to 32.7km/h, thus confirming the safety effects. As the decrease of the number of conflicts, it might be explained that car crashes and collision with pedestrians decreased by 62.2% and 66.7%. Also the result shows that the lowest point of speed in roundabouts appears near the yield line on the entry area on the roundabouts. When passing through the roundabouts, vehicles enter at a speed of 20-30km/h, which is the design speed of the circulatory lane and drive out the roundabout with a higher speed than the entry speed. CONCLUSIONS: When a roundabout is introduced at the intersections below certain traffic volume there are effects of traffic operation, traffic safety, and traffic behavior.

이 연구는 회전교차로의 운영효율을 다루고 있다. 회전교차로는 일반적으로 높은 용량, 지체감소, 안전개선 등의 장점을 가지고 있다. 원형교차로는 통행우선권에 따라 로터리와 회전교차로로 나눌 수 있다. 이 연구의 목적은 시나리오에 따른 로터리와 회전교차로의 운영효율을 비교 분석하는데 있다. 이를 위해 이 연구는 진입교통량과 방향별 교통량에 따른 256개의 시나리오를 설정하고, VISSIM을 사용하여 지체를 분석하는데 중점을 두고 있다. 주요 결과는 다음과 같다. 첫째, 로터리의 평균지체가 회전교차로의 차량지체보다 1.56-8.74배 높은 것으로 분석되었다. 둘째, 주도로와 부도로의 교통량 비율의 차이가 클수록 운영효율이 더 좋은 것으로 분석되었다. 셋째, 4지 교차로의 평균지체가 3지 교차로보다 1.77-11.70배 높은 것으로 평가되었다. 마지막으로 2차로(3지와 4지) 교차로가 1차로(3지와 4지) 교차로에 비해 2.02-2.23배 많은 교통량을 수용할 수 있는 것으로 분석되었다.

이 연구는 회전교차로의 효과를 다루고 있다. 연구의 목적은 로터리를 회전교차로로 전환함에 따른 운영효과를 비교 분석하는데 있다. 이를 위해 이 연구에서는 국내에서 운영되고 있는 로터리 20개 지점을 조사하고, VISSIM을 통해 개선 전 후의 네트워크를 구축하며, 그 효과를 비교분석하는데 중점을 두고 있다. 국내의 로터리는 효과적인 회전교차로 운영을 위하여 기하구조 측면에서 많은 개선이 필요한 것으로 분석되었다. 연구의 주요결과는 다음과 같다. 첫째, 현재 교통량을 적용하였을 경우 로터리의 운영효과는 다소 좋은 것으로 나타나지만 그 차이는 매우 적은 것으로 평가되었다. 둘째, 도시부 로터리의 경우 교통량이 증가할수록 차량당 평균지체가 급격히 증가하는 것으로 분석되었다. 마지막으로 지방부의 경우 도시부에 비해 교통량이 적기 때문에 회전교차로의 평균속도는 로터리에 비해 약 10km/h의 속도저감효과를 갖는 것으로 평가되었다.

한 시대나 사회의 얼굴매력에 대한 관점을 영화배우 등 인기연예인의 얼굴분석을 통해 알 수 있다는 가정 하에 물리적 특징에 기반 한 한국 및 외국 연예인 얼굴 의 교차 문화적 특징 및 추세를 알아보았다. 얼굴인상감성모형을 이용하여 각 연예인얼굴의 물리적 특징을 측정하고 얼굴유형을 분류하였다. 분석대상은 한국의 여자연예인 47명, 남자연예인 47명, 외국 여자연예인 116명과 남자연예인 87명으로 총 297명이었다. 교차문화적인 분석에서 나타난 한국과 외국의 남녀 연예인 얼굴의 공통적인 특징은 날카로운 인상이었다.

The purpose of this study was to compare acupuncture-like transcutaneous electrical nerve stimulation(ALTENS) with conventional transcutaneous electrical nerve stimulation(C-TENS) for crossover effect in healthy subjects. Forty subjects recieved ALTENS(20 persons), C-TENS(20 persons) to one upper extremity. Each technic was applied to the motor point of the wrist extensor muscle group for twenty-minutes. With the subject placed in supine the technics were applied at 80 Hz, 2-10 mA(ALTENS) and 10 Hz, 4-12 mA(C-TENS). Results revealed: (1) a significant difference between the pretreatment and posttreatment in each group(p<.05) (2) no significant difference between ALTENS and C-TENS(p>.05). In conclusion, there was no difference between ALTENS and C-TENS for crossover effect.

In study, we have developed permeable concrete for rotary intersections and tried to compare the basic properties with existing permeable concrete.

골다공증의 진단에서 이중에너지 X선 흡수계수법은 가장 빈번하게 사용되는 검사이다. 외국의 골밀도 장치 제조사인 지이나 홀로직 장치에 대한 교차분석 연구는 다양하나 국내 제조사 이중에너지 X선 흡수골밀도 장치에 대한 비교 분석이 부족하다. 이에 본 연구에서는 국내 제조사의 이중에너지 X선 흡수골밀도 장치와 해외 제조사의 이중에너지 X선 흡수 골밀도 장치의 교차분석을 시행하여 교차식을 수립하였다. 유럽인 척추 팬텀을 이용한 검사에서 가장 높은 표준 편차를 보인 Dexxum T 장치의 경우 상. 중. 하부 척추에서0.030, 0.029, 0.037를 보였고, 홀로직의 Horizon Ci에서는 0.005와 0.004로 하부와 중간 척추에서 가장 낮은 표준편차를 나타냈다. 오스테오 프로맥스 장치의 경우 상부 척추에서 0.005의 표준편자를 나타냈다. 본 연구에서 도출한 국내·외 이중에너지 흡수 골밀도 장치의 교차식은 임상환경에서 골밀도 검사의 추척 검사에 유용한 사례가 될 것이다. 또한 본 연구에서 제시한 국산 이중에너지 X선골밀도 장치에 대해 설정된 교차 방정식에 기초로 임상환경에서 보다 정확한 골밀도 추적 관찰을 위해 보다 다양한 국산 이중에너지 X선 골밀도 장치의 교차 보정을 설정하는 것이 필요하다.