• Title/Summary/Keyword: Intersection control

Search Result 264, Processing Time 0.026 seconds

Operation Analysis of Downstream Intersections at Urban Freeway Off-ramps (도시고속도로 진출램프 하류부교차로 운영 분석 (중동 IC 사례 분석을 중심으로))

  • Jeon, Jae-Hyeon;Kim, Young-Chan;Jeoung, Young-Je
    • Journal of Korean Society of Transportation
    • /
    • v.26 no.4
    • /
    • pp.7-16
    • /
    • 2008
  • Severe congestion is happening at urban freeway off-ramps in Seoul. Major causes of congestion at off-ramps are a shortage of capacity and inefficient signal operations at the downstream intersection at off-ramps. It is necessary to control congestion by improving design or operations in the downstream intersection. In this study, the authors analyzed the case of the Jungdong interchange that was improved for design in the downstream intersection. When a freeway and an arterial road cross, diamond interchanges are usually selected with a single-point urban interchange (SPUI) as an alternative. To compare the effectiveness of a diamond interchange with a SPUI, the authors applied these two configurations to the Jungdong interchange using a simulation. The result of the analysis shows that congestion at off-ramps in diamond interchanges can be reduced by improving signal operations such as the application of "4 phase with overlaps" and that diamond interchanges are more efficient than a SPUI with a frontage road. Efficient operation of the downstream intersection by these findings can minimize congestion of not only the downstream intersection but also the freeway mainline.

Properties of object composition operations for object-oriented CAD database systems

  • Chang, Tae-Soo;Tanaka, Katsumi
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1989.10a
    • /
    • pp.1016-1021
    • /
    • 1989
  • In this paper, we introduce a recursively-defined natural join operation as well as well-known object composition operations (union, intersection) for composing CAD database objects. Then, we will discuss how to realize these operations by the message passing computing mechanism. Next, we will discuss what kind of behaviours (methods) are preserved under our natural join operations. Finally, we investigate mathematical properties about the relationships among several object composition operations (natural join, union and intersection).

  • PDF

Three-Dimensional Positioning Using EROS A Stereo Pairs

  • Teo, Tee-Ann;Chen, Liang-Chien
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.606-608
    • /
    • 2003
  • This paper investigates the accuracy of three-dimensional positioning for EROS A stereo pairs when different numbers of ground control points are employed. The major works of the proposed schemes include: (1) initialization of orientation parameters (2) preliminary orbit fitting, (3) orbit refinement using the least squares filtering technique, and (4) space intersection. The experiment includes validation of positioning accuracy for an EROS A in-track stereo pair when different number of check points are employed.

  • PDF

Design of prevention spillback agorithm using fuzzy rule

  • Hong, Yousik;Cho, Hyungki;Park, Chongkug
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1996.10a
    • /
    • pp.32-35
    • /
    • 1996
  • Traffic signal cycle optimization is one of the most efficient ways for reducing fuel consumption and improving vehicle waiting time of highsaturated traffic conditions. But most research focused on lowsaturated traffic conditions. Only a few studies have researched traffic control for highsaturated traffic conditions. In this paper reviews the problem of conventional traffic signal system and creates optimal traffic cycle of at the bottom traffic intersection using 27 fuzzy rules. Moreover, to prevent spillback, it can adapt control even though upper traffic intersection has a different saturation rate, road length, road slope and road width.

  • PDF

Evolutionary Design of Fuzzy Classifiers for Human Detection Using Intersection Points and Confusion Matrix (교차점과 오차행렬을 이용한 사람 검출용 퍼지 분류기 진화 설계)

  • Lee, Joon-Yong;Park, So-Youn;Choi, Byung-Suk;Shin, Seung-Yong;Lee, Ju-Jang
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.16 no.8
    • /
    • pp.761-765
    • /
    • 2010
  • This paper presents the design of optimal fuzzy classifier for human detection by using genetic algorithms, one of the best-known meta-heuristic search methods. For this purpose, encoding scheme to search the optimal sequential intersection points between adjacent fuzzy membership functions is originally presented for the fuzzy classifier design for HOG (Histograms of Oriented Gradient) descriptors. The intersection points are sequentially encoded in the proposed encoding scheme to reduce the redundancy of search space occurred in the combinational problem. Furthermore, the fitness function is modified with the true-positive and true-negative of the confusion matrix instead of the total success rate. Experimental results show that the two proposed approaches give superior performance in HOG datasets.

Bitmap Intersection Lookup (BIL);A Packet Classification's Algorithm with Rules Updating

  • Khunkitti, Akharin;Promrit, Nuttachot
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.767-772
    • /
    • 2005
  • The Internet is a packet switched network which offers best-effort service, but current IP network provide enhanced services such Quality of Services, Virtual Private Network (VPN) services, Distribute Firewall and IP Security Gateways. All such services need packet classification for determining the flow. The problem is performing scalable packet classification at wire speeds even as rule databases increase in size. Therefore, this research offer packet classification algorithm that increase classifier performance when working with enlarge rules database by rearrange rule structure into Bitmap Intersection Lookup (BIL) tables. It will use packet's header field for looking up BIL tables and take the result with intersection operation by logical AND. This approach will use simple algorithm and rule structure, it make classifier have high search speed and fast updates.

  • PDF

Robust inference with order constraint in microarray study

  • Kang, Joonsung
    • Communications for Statistical Applications and Methods
    • /
    • v.25 no.5
    • /
    • pp.559-568
    • /
    • 2018
  • Gene classification can involve complex order-restricted inference. Examining gene expression pattern across groups with order-restriction makes standard statistical inference ineffective and thus, requires different methods. For this problem, Roy's union-intersection principle has some merit. The M-estimator adjusting for outlier arrays in a microarray study produces a robust test statistic with distribution-insensitive clustering of genes. The M-estimator in conjunction with a union-intersection principle provides a nonstandard robust procedure. By exact permutation distribution theory, a conditionally distribution-free test based on the proposed test statistic generates corresponding p-values in a small sample size setup. We apply a false discovery rate (FDR) as a multiple testing procedure to p-values in simulated data and real microarray data. FDR procedure for proposed test statistics controls the FDR at all levels of ${\alpha}$ and ${\pi}_0$ (the proportion of true null); however, the FDR procedure for test statistics based upon normal theory (ANOVA) fails to control FDR.

A Study on Operation Methodology of A Signalized Intersection Based on Optimization of Lane-Uses (차로배정 최적화를 고려한 신호교차로 운영방안에 관한 연구)

  • Kim, Ju Hyun;Shin, Eon Kyo
    • International Journal of Highway Engineering
    • /
    • v.15 no.6
    • /
    • pp.125-133
    • /
    • 2013
  • PURPOSES : The purpose of this study is to propose delay-minimizing operation methodology of a signalized intersection based upon optimization of lane-uses on approaching lanes for an intersection. METHODS : For the optimization model of lane-uses, a set of constraints are set up to ensure feasibility and safety of the lane-uses, traffic flow, and signal settings. Minimization of demand to saturation flow ratio of a dual-ring signal control system is introduced to the objective function for delay minimization and effective signal operation. Using the optimized lane-uses, signal timings are optimized by delay-based model of TRANSYT-7F. RESULTS : It was found that the proposed objective function is great relation with delay time for an intersection. From the experimental results, the method was approved to be effective in reducing delay time. Especially, cases for two left-turn lanes reduced greater delays than those for a left turn lane. It is noticed that the cases for different traffic volume by approach reduced greater delays than those for the same traffic volume by approach. CONCLUSIONS : It was concluded that the objective function is proper for lane-uses optimizing model and the operation method is effective in reducing delay time for signalized intersections.

3D Linear and Circular Interpolation Algorithm for CNC Machines (CNC 공작기계의 3차원 직선 및 원호 보간 알고리즘에 관한 연구)

  • Yang, Min-Yang;Hong, Won-Pyo
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.16 no.9
    • /
    • pp.172-178
    • /
    • 1999
  • 3D linear and circular interpolations are a basic part for the machining of complex shapes. Until now, because of the absence of appropriate algorithms for the generation of 3D lines and circles, a full accomplishment for available machine tool resolution is difficult. this paper presents new algorithms for 3D linear and circular interpolation in the reference pulse technique. In 3D space, the line or circle is not expressed as an implicit function, it is only defined as the intersection of two surfaces. A 3D line is defined as the intersection of two planes, and a 3D circle is defined as the intersection of a plane and the surface of a sphere. Based on these concepts, interpolation algorithms are designed to follow intersection curves in 3D space, and a real-time 3D linear and circular interpolator was developed in software using a PC. The algorithm implemented in a PC showed promising results in interpolation error and speed performance. It is expected that it can be applied to the next generation computerized numerical control systems for the machining of 3D lines, circles and some other complex shapes.

  • PDF

Development of Computation Model for Traffic Accidents Risk Index - Focusing on Intersection in Chuncheon City - (교통사고 위험도 지수 산정 모델 개발 - 춘천시 교차로를 중심으로 -)

  • Shim, Kywan-Bho;Hwang, Kyung-Soo
    • International Journal of Highway Engineering
    • /
    • v.11 no.3
    • /
    • pp.61-74
    • /
    • 2009
  • Traffic accident risk index Computation model's development apply traffic level of significance about area of road user group, road and street network area, population group etc.. through numerical formula or model by countermeasure to reduce the occurrence rate of traffic accidents. Is real condition that is taking advantage of risk by tangent section through estimation model and by method to choose improvement way to intersection from outside the country, and is utilizing being applied in part business in domestic. However, question is brought in the accuracy being utilizing changing some to take external model in domestic real condition than individual development of model. Therefore, selection intersection estimation element through traffic accidents occurrence present condition, geometry structure, control way, traffic volume, turning traffic volume etc. in 96 intersections in this research, and select final variable through correlation analysis of abstracted estimation elements. Developed intersection design model taking advantage of signal type, numeric of lane, intersection type, analysis of variance techniques through ANOVA analysis of three variables of intersection form with selected variable lastly, in signal crossing through three class intersection, distinction variable choice risk in model, no-signal crossing risk distinction analysis model and so on develop.

  • PDF