scholarly journals Failure of classical traffic flow theories: Stochastic highway capacity and automatic driving

2016 ◽  
Vol 450 ◽  
pp. 700-747 ◽  
Author(s):  
Boris S. Kerner
Keyword(s):  
Traffic Flow ◽  
Highway Capacity ◽  
Automatic Driving ◽  
Flow Theories

Unsignalized Intersection Analysis: Effect of Overlapping Conflicting Traffic Flow on Minor Movement Potential Capacity

1997 ◽  
Vol 1572 (1) ◽  
pp. 86-98
Author(s):  
Christopher J. Fasching
Keyword(s):  
Traffic Flow ◽  
Level Of Service ◽  
Traffic Flows ◽  
Highway Capacity ◽  
Highway Capacity Manual ◽  
Capacity Estimate ◽  
Potential Capacity ◽  
Count Distribution ◽  
Intersection Analysis ◽  
Poisson Count

A particular component of two-way stop unsignalized intersection analyses as presented in the 1994 Highway Capacity Manual (HCM) is described. Specifically, advantages to minor movement capacity are evaluated where traffic flows overlap in multiple lanes. From vehicular arrival data collected by the author, it was determined that the current HCM can significantly underestimate the true potential capacity of minor movements that face multiple lanes of free-flow conflicting traffic. A modification to the HCM procedure is introduced in which an “effective” conflicting flow is calculated on the basis of “blockage” caused by individual lanes of traffic, assuming a Poisson count distribution. In every case examined (24 total), a more accurate potential capacity estimate resulted relative to that determined by the HCM procedure. The modification also resulted in a more accurate level of service in 8 of the 24 cases.

scholarly journals Analisis Kinerja Simpang Tak Bersinyal Jalan A.H. Nasution dan Jalan Cikadut, Kota Bandung. (Hal. 116-123)

2019 ◽  
Vol 5 (2) ◽  
pp. 116
Author(s):  
Muhammad Daryl Marta Pratama ◽  
Elkhasnet Elkhasnet
Keyword(s):  
Traffic Flow ◽  
Initial Conditions ◽  
Degree Of Saturation ◽  
Residential School ◽  
Highway Capacity ◽  
Highway Capacity Manual ◽  
The Road ◽  
Traffic Jams ◽  
Shopping Area ◽  
The City

ABSTRAKPersimpangan merupakan suatu bagian jalan yang menjadi pusat pertemuan dari berbagai pergerakan arus lalu lintas. Pada tipe simpang tak bersinyal, sering dijumpai titik-titik konflik arus lalu lintas yang mengakibatkan kemacetan arus lalu lintas terutama pada saat jam-jam sibuk. Contoh kasus terdapat di Kota Bandung, terjadi pada persimpangan Jalan A.H. Nasution dan Jalan Cikadut. Lokasi ini dipilih karena selain kemacetan yang disebabkan oleh titik-titik konflik arus lalu lintas yang tidak teratur pada saat jam sibuk, di sekitar jalan pada simpang ini juga merupakan kawasan pertokoan, pemukiman, sekolah dan juga terdapat pom bensin. Berdasarkan permasalahan tersebut, dilakukan perhitungan dan analisis data pada kondisi awal simpang, didapat nilai derajat jenuh (DS) sebesar 0,983 untuk pagi hari dan 0,937 untuk sore hari. Karena hasil perhitungan simpang pada kondisi awal tidak memenuhi syarat MKJI 1997, yaitu DS < 0,85, maka perlu dilakukan perhitungan ulang dengan beberapa alternatif agar nilai DS bisa memenuhi.Kata kunci: persimpangan, kemacetan, derajat jenuh, MKJI 1997. ABSTRACTIntersection is a part of the road that becomes the center concourse of various traffic flow movements. In the type of unsignalized intersection, there are often traffic flow conflict points which cause traffic jams, especially during rush hour. Examples of cases are in the City of Bandung, occurred at the intersection of A.H. Nasution Street and Cikadut Street. This location was chosen because in addition to congestion caused by irregular traffic flow conflict points during rush hour, around the road at the intersection this is also a shopping area, residential, school and gas station. Based on these problems, data calculations and analysis are carried out in the initial intersection condition, obtained saturated degree (DS) values of 0,983 in the morning and 0,937 in the afternoon. Because the results of the intersection calculation in the initial conditions did not comply the requirements of the Indonesian Highway Capacity Manual of 1997 (IHCM 1997), that’s DS < 0,85, it is necessary to recalculate with some alternative that value of DS can comply.Keywords: intersection, congestion, degree of saturation, IHCM 1997.

scholarly journals Passenger Car Equivalents on Downgrades of Two-Lane Roads

2020 ◽  
Vol 15 (4) ◽  
pp. 152-173
Author(s):  
Marko Subotić ◽  
Željko Stević ◽  
Edis Softić ◽  
Veljko Radičević
Keyword(s):  
Traffic Flow ◽  
Cross Sections ◽  
Negative Influence ◽  
Flow Conditions ◽  
Highway Capacity ◽  
Passenger Car ◽  
Highway Capacity Manual ◽  
Average Value ◽  
Vehicle Structure ◽  
Passenger Car Equivalent

In this paper, empirical research about Passenger Car Equivalents (PCEs) on the longitudinal downgrade of two-lane roads in Bosnia and Herzegovina has been conducted in order to determine the influence of vehicle structure under free traffic flow conditions. The research has been carried out considering the classes of vehicles at cross-sections on the downgrade of two-lane roads. As a result, the negative influence of vehicle structure under free traffic flow conditions using passenger car equivalents (PCEs) has been determined. The results show that on the downgrade of two-lane roads, the value of passenger car equivalent decreases from the level terrain to the boundary minimum value for the determined downgrade g = −3.00%, after which its value starts to increase slightly. Based on the obtained values, the models calibrated with a second-degree polynomial have been developed to determine the average value of passenger car equivalent as a function of its boundary value. The paper also compares the results obtained by the developed models with the models from the Highway Capacity Manual under free traffic flow conditions. In addition, models for the percentage values of PCE15%, PCE50% and PCE85% have been established.

scholarly journals EVALUASI FAKTOR HAMBATAN SAMPING PADA PENENTUAN KAPASITAS JALAN STUDI KASUS: JALAN GATOT SUBROTO

2021 ◽  
Vol 4 (3) ◽  
pp. 783
Author(s):  
Muhamad Faisal ◽  
Najid Najid
Keyword(s):  
Traffic Flow ◽  
Observation Data ◽  
Questionnaire Data ◽  
Highway Capacity ◽  
The Road ◽  
Traffic Performance ◽  
Factor Data ◽  
Side Friction ◽  
Motorized Vehicles ◽  
Drag Factor

Overcrowding often occurs in DKI Jakarta, especially on Jalan Gatot Subroto. This location is one of the biggest business centers in Jakarta. Roadside activities that impede traffic flow are called side friction. Side friction is an impact on traffic performance resulting from road segment activities. Highway capacity is also influential. That happens because the available highway capacity is no longer able to accommodate the increasing traffic flow. Therefore, research was conducted. To calculate the highway capacity, observations were made to see the number of vehicles. It takes the perception of side frictions using questionnaire data. Questionnaire data collected  100 respondents. So, the results show that section is in the VL (Very Low) side obstacle class, which occurs in the morning while the L (Low) side obstacle class occurs in the afternoon and evening. The results estimation of the side drag factor data shows that the volume is greater than the highway capacity. The correlation between observation data and questionnaire results vehicles parked or stopped on the side of the road and vehicles from roadside access have a sequential weight order, while pedestrians and non-motorized vehicles have non-sequential weights. Further research to expand the questionnaire and get more precise results. ABSTRAKKepadatan sering terjadi di DKI Jakarta khususnya di Jalan Gatot Subroto. Lokasi ini salah satu pusat bisnis terbesar di Jakarta. Aktivitas sisi jalan dapat menghambat arus lalu lintas disebut hambatan samping. Hambatan samping merupakan dampak terhadap kinerja lalu lintas yang dihasilkan dari aktivitas segmen jalan. Selain itu, kapasitas jalan juga berpengaruh. Hal ini terjadi karena kapasitas jalan yang tersedia sudah tidak mampu untuk menampung arus lalu lintas yang semakin tertambah kepadatannya. Oleh karena itu dilakukan penelitian. Untuk menghitung kapasitas jalan, dilakukan observasi untuk melihat jumlah kendaraan. Selain itu, dibutuhkan persepsi hambatan samping menggunakan data kuesioner. Data kuesioner terkumpul sebanyak 100 responden. Maka, hasil menunjukan ruas Jalan Gatot Subroto berada di kelas hambatan samping VL (Very Low) terjadi di waktu pagi hari sedangkan kelas hambatan samping L (Low) terjadi di waktu siang dan sore hari. Hasil dari estimasi faktor hambatan samping data menunjukan volume lebih besar daripada kapasitas jalan. Korelasi anatra data observasi dengan hasil kuesioner menunjukan bahwa kendaraan parkir atau berhenti di sisi jalan dan kendaraan dari akses sisi jalan memiliki urutan bobot yang berurutan sedangkan untuk pejalan kaki dan kendaraan tidak bermotor memiliki bobot yang tidak berurutan. Penelitian selanjutnya, diharapkan dapat memperluas kuesioner dan mendapatkan hasil yang lebih tepat.

scholarly journals AFFINITY PROPAGATION CLUSTERING IN DEFINING LEVEL OF SERVICE CRITERIA OF URBAN STREETS

Transport ◽  
2014 ◽  
Vol 29 (4) ◽  
pp. 401-411 ◽  
Author(s):  
Prasanta Kumar Bhuyan ◽  
Smruti Sourava Mohapatra
Keyword(s):  
Traffic Flow ◽  
Heterogeneous Traffic ◽  
Level Of Service ◽  
Highway Capacity ◽  
Highway Capacity Manual ◽  
Urban Streets ◽  
Urban Street ◽  
Indian Context ◽  
Validation Parameters ◽  
Street Segments

Defining Level Of Service (LOS) criteria is very important as this is the first step of LOS analysis but this is not well defined in Indian context. The analysis followed in India is basically adaptation of Highway Capacity Manual (HCM 2000) methodology which is more suitable for developed countries having homogenous traffic pattern. An attempt has been made in this study to define LOS criteria of urban streets for developing countries having heterogeneous traffic flow condition. Defining LOS is basically a classification problem and to solve it Affinity Propagation (AP), a very recently developed cluster algorithm is used. Inventory details and the required speed data are collected from five major street corridors of Greater Mumbai Region in India through the application of Trimble GeoXT Global Positioning System (GPS) receiver. Six validation parameters are used on Free Flow Speed (FFS) data to find the optimal number of clusters, which is required for the classification of street segments into number of classes. After that speed data collected during both peak and off-peak hours are averaged over street segments and clustered into six groups to get the speed ranges of different LOS categories. Using validation parameters, considering the physical and surrounding environmental characteristics it is found that street segments can be classified into four classes in Indian context as mentioned in Highway Capacity Manual 2000. However, the FFS range for urban street class IV (urban design category) is significantly lower because of varying road geometric characteristics. The speed ranges of LOS categories under urban street classes are proportionately lower to that values mentioned in HCM 2000 because of highly heterogeneous traffic flow on urban Indian roads. The travel speed data collection procedure using GPS is simple and accurate. In addition, AP clustering is highly efficient in terms of time saving and provides a very accurate solution to classification problems. Hence, both GPS and AP techniques can be applied in other countries to define the speed ranges of LOS categories considering the local conditions.

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