• Title/Summary/Keyword: car following

Search Result 238, Processing Time 0.024 seconds

Analysis of Emission Gas Characteristics for Gasoline Vehicles using the Inspection Results of Car Emission (운행차 배출가스 정밀검사 결과를 이용한 가솔린 차량에 대한 배출가스 특성 분석)

  • Roh, Hyun Gu
    • Journal of ILASS-Korea
    • /
    • v.23 no.3
    • /
    • pp.128-135
    • /
    • 2018
  • In this study, the following conclusions could be obtained from the analysis of emissions contribution rates and features for contaminated emissions by 13,456 gasoline vehicles passed in the vehicle load test (ASM-idle) under the inspection year 2013 to 2017. It was confirmed that the contamination of the CO, HC, NOx by the displacement is reduced on over 3L engine. As a result of comparing the exhaust gas in the low speed idle mode and the AS2525 mode, the exhaust gas in the low speed idle mode was measured high. It is estimated that if ISG function is applied, emissions from idle condition will be reduced. NOx emissions were reduced when the engine power was above 200HP. It has been confirmed that the amount of exhaust emissions are significantly reduced for vehicles manufactured after 2004. As a result of analyzing the exhaust gas according to the season, it is judged that there is a correlation between HC and NOx according to the ambient temperature. The concentration of exhaust emission in vehicles with high accumulated distance increases, which is considered to be the result of aging of the vehicle.

Boundary Line Extract for Moving Object Tracking (이동 물체 추적을 위한 경계선 추출)

  • Kim, Tea-Sik;Lee, Ju-Shin
    • Journal of the Korean Institute of Telematics and Electronics T
    • /
    • v.35T no.2
    • /
    • pp.28-34
    • /
    • 1998
  • In this paper, I'd like to make a suggestion for boundary line detect algorithm which is used 3-D image processing system in order to track moving object. Through this study, more than anything else, difference image method was adopted to detect moving object in input image. To detect moving object, I made use of detect windows constructed by 4's predictive areas and object area for the purpose of reducing processing time and its size was determined by the size of moving object and prediction parameter directed center position. And also, tracking camera was movable toward the direction of X, Y by DC motor. As a conclusion of the study proposed algorithm, I found out the following results that tracking error was less than 6% of total moving object size and maximum tracking time 2 seconds by toy-car simulation.

  • PDF

Surgical Repair of Rostral Hemimandibular Fractures with Canine Tooth Luxation in a Dog (개에서 견치 탈구를 동반한 앞쪽 하악골 골절의 수술적 정복 1례)

  • Yoon, Hun-Young;Kang, Myung-Gon;Jeong, Soon-Wuk
    • Journal of Veterinary Clinics
    • /
    • v.26 no.4
    • /
    • pp.359-361
    • /
    • 2009
  • A sexually intact female Alaskan Malamute, 5-year-old weighing 25.2 kg presented to the Hangang Animal Hospital, following hit-by-car. On initial presentation, the dog had severe salivation and the right canine tooth luxation. Radiographs revealed fractures of the right rostral hemimandible with the right canine tooth luxation and symphyseal separation. Surgical repair of fractures was performed by use of an interdental wiring technique and external fixation technique that included pins, an acrylic connecting bar, and polymethyl methacrylate bone cement. Post-operative radiographs revealed that bridging callus was well formed over cortices of the fracture area. Pins and an acrylic connecting bar were removed 7 weeks post-operatively. The dog exhibited evidence of normal mastication.

A Methodology for Providing More Reliable Traffic Safety Warning Information based on Positive Guidance Techniques (Positive Guidance 기법을 응용한 실시간 교통안전 경고정보 제공방안)

  • Kim, Jun-Hyeong;O, Cheol;O, Ju-Taek
    • Journal of Korean Society of Transportation
    • /
    • v.27 no.2
    • /
    • pp.207-214
    • /
    • 2009
  • This study proposed an advanced warning information system based on real-time traffic conflict analysis. An algorithm to detect and analyze unsafe traffic events associated with car-following and lane-changes using individual vehicle trajectories was developed. A positive guidance procedure was adopted to provide warning information to alert drivers to hazardous traffic conditions derived from the outcomes of the algorithm. In addition, autoregressive integrated moving average (ARIMA) analyses were conducted to investigate the predictability of warning information for the enhancement of information reliability.

Traumatic ventricular septal defect in a 4-year-old boy after blunt chest injury

  • Kim, Yun-Mi;Yoo, Byung-Won;Choi, Jae-Young;Sul, Jun-Hee;Park, Young-Hwan
    • Clinical and Experimental Pediatrics
    • /
    • v.54 no.2
    • /
    • pp.86-89
    • /
    • 2011
  • Traumatic ventricular septal defect (VSD) resulting from blunt chest injury is a very rare event. The mechanisms of traumatic VSD have been of little concern to dateuntil now, but two dominant theories have been described. In one, the rupture occurs due to acute compression of the heart; in the other, it is due to myocardial infarction of the septum. The clinical symptoms and timing of presentation are variable, so appropriate diagnosis can be difficult or delayed. Closure of traumatic VSD has been based on a combination of heart failure symptoms, hemodynamics, and defect size. Here, we present a case of a 4-year-old boy who presented with a traumatic VSD following a car accident. He showed normal cardiac structure at the time of injury, but after 8 days, his repeated echocardiography revealed a VSD. He was successfully treated by surgical closure of the VSD, and has been doing well up to the present. This report suggests that the clinician should pay great close attention to the patients injured by blunt chest trauma, keeping in mind the possibility of cardiac injury.

The Effect of $Mg^#$, $Ca^#$, $Na^+$, $K^+$ and Creatine Phosphate on the ATPase Activity of Microsomal Fraction from Rabbit Uterus (가토자궁근(家兎子宮筋)에서 분리(分離)한 Microsome 분획내(分劃內) Adenosinetriphosphatase 활성도(活性度)에 미치는 $Mg^#$, $Ca^#$, $Na^+$, $K^+$ 및 Creatine phosphate의 영향(影響))

  • Choi, Sin-Jyoung
    • The Korean Journal of Pharmacology
    • /
    • v.2 no.2
    • /
    • pp.35-42
    • /
    • 1966
  • The author investigated the effect of $Mg^#$, $Ca^#$, $Na^+$, $K^+$ and creatine phosphate on the ATPase activity of microsomal fraction isolated from rabbit uterus and obtained the following results : 1) The uterine microsomal fraction contained the $Na^+-$ and $K^+-$ activated ATPase in the presence of $Mg^#$. The ATPase activity increased with protein content in the fraction. 2) The maximum ATPase activity was obtained at $Na^+$ and $K^+$ concentraction of 100 mM respectively. 3) In the absence of $Mg^#$, the ATPase was not activated by $Na^+$ and $K^+$, but inhibited. 4) Car stimulated the $Na^+-$ and $K^+-$ activated ATPase in the presence of $Mg^#$. However, in the absence of $Mg^#$, the ATPase was not activated by $Ca^#$. 5) The $K^+-$ activated ATPase activity was greater than the $Na^+-activated$ ATPase under all conditions. 6) The $Na^+-$ and $K^+$ activated ATPase activity was increased by addition of creatine phosphokinase and creatine phosphate to the reaction mixture.

  • PDF

A Study on Purchasing Agricultural Products of Re-visitors In Traditional Market Using Double Hurdle Model (더블허들 모형을 이용한 전통시장 재방문객의 농산물 구입결정 요인에 관한 연구)

  • Yi, Hyangmi
    • Journal of Korean Society of Rural Planning
    • /
    • v.21 no.2
    • /
    • pp.137-147
    • /
    • 2015
  • In this study, consumers who have experience of visiting Jeongsun Arirang Market has been selected as samples to understand the characteristics of agricultural products purchase. For this, double hurdle model was used in order to resolve sample selection problem and obtain consistent estimator. The key points are the following. First, as the age increases(up to 59.8 years), chances of purchasing the products at traditional market increase as income increases. Second, when the residence area is outside of Gangwon-province, the purchase amount of the products increased compared to those from visitors within the Gangwon province. Also, visitors who use public transportations purchase less products compared to those who use their own car. Third, probability of agricultural products increase as the visitors consider positive effect the product purchase leads to the local farmers. Fourth, if the visitors consider the quality of the agricultural products, probability of purchasing agricultural product at the site increases. However, if the visitors consider the freshness of the agricultural products, the purchase amount rather drops. Fifth, the probability of purchase increases as visitors consider the brand of traditional market.

Longitudinal Control of Acceleration Lanes and its Impact on Congestion Alleviation (가속차로의 길이 제어와 고속도로 접속부 혼잡저감 효과)

  • Shin, Chi-Hyun;Kim, Kyu-Ok
    • Journal of Korean Society of Transportation
    • /
    • v.23 no.5 s.83
    • /
    • pp.169-176
    • /
    • 2005
  • This paper introduces the dynamic control of acceleration lanes at freeway-ramp junctions. The feasibility of operation with flexible length of acceleration lane was tested with most possible traffic conditions. The operational qualify was also evaluated using average speed and total thru-put at both ramp section and freeway section. A CORSIM microscopic simulation model was used to evaluate the operation quality with a variety or volume conditions and three acceleration lanes, each representing different length categories. In addition, tollgate O-D data including travel times were obtained for two sections on the Gyeong-bu Freeway where an effective merging distance has been largely reduced. Its effect was analyzed and compared to the simulation results. Finally, the effects of acceleration lane are discussed and operational improvement at junctions is presented as research findings.

Calculation of Sidewall Lateral Stiffness of a Radial Tire Using Material Properties of Rubber Compounds (고무배합물의 물성을 이용한 레이디얼 타이어의 사이드월 횡강성 계산)

  • Kim, Yong-Woo;Kim, Jong-Guk
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.27 no.10
    • /
    • pp.1667-1675
    • /
    • 2003
  • This paper has considered the calculation of lateral stiffness of radial tire's sidewall, which consists of cord stiffness and rubber sheet stiffness, by using the material constants of rubber compounds of tire. We have suggested and illustrated how to calculate the rubber sheet lateral stiffness by considering the following aspects. First, the rubber sheet consists of various kinds of rubber compounds with different thickness along the sidewall in the radial direction. Secondly, equivalent Young's modulus of the rubber sheet can be calculated by using available experimental data of rubber compounds. The present method enables us to divide the calculation domain as many as we want, which can reduce numerical error in the calculation of geometrical and mechanical properties. We have illustrated the calculation by using the data of the radial tire for passenger car of P205/60R15.

A Microscopic Analysis on the Fundamental Diagram and Driver Behavior (교통기본도와 운전자 행태에 대한 미시적 분석)

  • Kim, Taewan
    • International Journal of Highway Engineering
    • /
    • v.14 no.6
    • /
    • pp.183-190
    • /
    • 2012
  • PURPOSES : The fundamental diagram provides basic information necessary in the analysis of traffic flow and highway operation. When traffic flow is congested, the density-flow points in the fundamental diagram are widely scattered and move in a stochastic manner. This paper investigates the pattern of density-flow point transitions and identifies car-following behaviors underlying the density-flow transitions. METHODS : From a microscopic analysis of 722 fundamental diagrams of NGSIM data, a total of 20 transition patterns of fundamental diagrams are identified. Prominent features of the transition patterns are explained by the behavior of the leader and follower. RESULTS : It is found out that the average speed and the speed difference between the leader and the follower critically determine the density-flow transition pattern. The density-flow path is very sensitive to the values of vehicle speed and spacing especially at low speed and high density such that most fluctuations in the fundamental diagram in the congested regime is due to the noise of speed and spacing variations. CONCLUSIONS : The result of this study suggests that the average speed, the speed difference between the leader and the follower, and the random variations of speed and spacing are dominant factors that explain the transition patterns of a fundamental diagram.