scholarly journals Estimation of truck reduction factors applicable to calculation of parameters of a regulated intersection

2021 ◽  
Vol 18 (5) ◽  
pp. 544-553
Author(s):  
V. V. Donchenko ◽  
A. N. Shumskiy
Keyword(s):  
Traffic Flow ◽  
Road Traffic ◽  
Passenger Cars ◽  
Passenger Car ◽  
Calculation Of Parameters ◽  
Significant Difference ◽  
Car Park ◽  
Transport Problems ◽  
Reduction Factors ◽  
Freight Vehicles

Introduction. The rapid growth of the country’s car park and the increasing rate of traffic volume lead to various types of transport problems. This is especially acute in regulated areas located near logistics parks, as well as in industrial zones of cities. Here, in the general traffic flow, trucks prevail, which differ from passenger cars primarily in their overall dimensions and dynamic characteristics. For the uniformity of the traffic flow, a certain difference is compensated by specialized coefficients of converting to a conventional passenger car. The performed research is aimed at establishing the main methods used in bringing freight vehicles to a conventional passenger car and assessing the current coefficients of converting freight vehicles to a conventional passenger car by determining the value of the reduced traffic intensity.Methods and materials. Within the framework of the study performed, natural methods of data collection were used for the subsequent calculation. When analyzing certain parameters, mathematical models have been established that underlie certain values of the coefficients of converting trucks to a conventional passenger car.Results. In the course of the study, the authors classified the methods for determining the coefficients of bringing a truck to a conventional passenger car. The values of the reduction factors for some of them have been established, which can be used when calculating the parameters of the regulated section. The present value of road traffic on the set object of the study - the regulated intersection - has been calculated using different actuation coefficients established earlier. The results obtained are assessed.Conclusion. The analysis of the values obtained as a result of calculations showed their significant difference from each other with a difference of 12%, 53% and 300% of the value of the total (not reduced) intensity. Based on the results obtained, the main tasks of further research are determined.

scholarly journals Analyzing the Impact of Trucks on Traffic Flow Based on an Improved Cellular Automaton Model

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Dewen Kong ◽  
Xiucheng Guo ◽  
Bo Yang ◽  
Dingxin Wu
Keyword(s):  
Cellular Automaton ◽  
Traffic Flow ◽  
Traffic Congestion ◽  
Traffic Volume ◽  
Cellular Automaton Model ◽  
Passenger Cars ◽  
Passenger Car ◽  
Car Following ◽  
Proposed Model ◽  
The Impact

This paper aims to analyze the impact of trucks on traffic flow and propose an improved cellular automaton model, which considers both the performance difference between passenger cars and trucks and the behaviour change of passenger cars under the impact of trucks. A questionnaire survey has been conducted to find out whether the impact of trucks exists and how the behaviour of passenger car drivers changes under the impact of trucks. The survey results confirm that the impact of trucks exists and indicate that passenger car drivers will enlarge the space gap, decelerate, and change lanes in advance when they are affected. Simulation results show that traffic volume is still affected by percentages of trucks in the congestion phase in the proposed model compared with traditional heterogeneous cellular automaton models. Traffic volume and speed decrease with the impact of trucks in the congestion phase. The impact of trucks can increase traffic congestion as it increases. However, it has different influences on the speed variance of passenger cars in different occupancies. In the proposed model, the relative relationship of the space gap between car-following-truck and car-following-car is changeable at a certain value of occupancy, which is related to the impact of trucks.

scholarly journals The effect of the traffic composition on the urban traffic capacity. Passenger car equivalent coefficients

2021 ◽  
Author(s):  
Dmitri Nemchinov ◽  
Dmitri Martiakhin ◽  
Pavel Pospelov ◽  
Tatiana Komarova ◽  
Alexandr Mikhailov
Keyword(s):  
Traffic Flow ◽  
Russian Federation ◽  
Urban Traffic ◽  
Heavy Vehicles ◽  
Passenger Cars ◽  
Passenger Car ◽  
Traffic Capacity ◽  
Equivalent Number ◽  
Passenger Car Equivalent ◽  
Traffic Composition

Predicting the traffic capacity and its elements requires bringing the traffic flow represented by various vehicles to uniformity expressed in the equivalent number of passenger cars, through the use of the passenger car equivalent coefficients (PCE). The currently used in Russian Federation passenger car equivalent coefficients are taken on the basis of studies of the capacity of the Russian Federation, carried out in the 70s - 80s of the last century on rural roads, where most of the vehicles were heavy vehicles. Currently, the traffic flow is mostly represented by passenger cars. The riding qualities of cars, especially trucks, have changed significantly. This situation is especially common to Moscow. In this regard, the question of clarifying the traffic flow composition and revising the passenger car equivalent coefficients becomes relevant. The article presents the methodology and results of studies carried out on the route sections between road crossings to determine the passenger car equivalent coefficients and the traffic composition in Moscow.

A COMPARATIVE STUDY TO DETERMINE THE KNEE JOINT FUNCTIONAL OUTCOME IN PATIENTS WITH FEMUR SHAFT FRACTURES MANAGED OPERATIVELY OR CONSEVATELY AT NDOLA HOSPITAL:complete enumeration (Preprint)

2019 ◽  
Author(s):  
Ripedah Nakana
Keyword(s):  
Knee Joint ◽  
Functional Outcome ◽  
Road Traffic ◽  
Femur Fracture ◽  
Conservative Group ◽  
Femur Fractures ◽  
Shaft Fractures ◽  
Significant Difference ◽  
Femur Shaft ◽  
Femur Shaft Fractures

BACKGROUND According to WHO, It has been reported that there has been a rise in road traffic accidents globally due to many factors. Consequently this has contributed to an increase in fracture of the femur in hospitals. The annual incidence of these Fractures has been estimated to be 10 per 100,000 persons and this incidence has been noticed to be higher among the youths decreasing after the age of 40 and then increasing in the elderly. These fractures are either managed conservatively or operatively. OBJECTIVE the aim of this study was to determine if there is a significant difference in knee joint functional outcome in patients with femur shaft fractures managed operatively and conservatively at Ndola Teaching Hospital at the orthopedics clinic and physiotherapy. This in future might help to place emphasis on government to sensitize the right measures needed to improve on the functional outcome of a knee joint in patients with femur fracture who are treated operatively or conservatively METHODS the method used for the study was a complete enumeration of all patients with femur fractures that were admitted at orthopedic ward, visited the orthopedic clinic and physiotherapy sessions at NTH between the period of July 2019 to September 2019. Data collected will be analyzed using a statistical data software called Statistical Package of Social Sciences (SPSS). The independent variable that will be considered in the study are age, DOI, DOA, femur shaft fractures, treatment and others that that will meet the selection Criteria. The dependent variable will be “Knee Joint Functional Outcome”. RESULTS Results did not show statistically significant difference in knee functional outcome for two methods (conservative or operative). In the current study it was noted that there was much reduction in swelling in the operative in comparison to the conservative group. We may therefore conclude that the operative management promises a better outcome especially when done on time. However it seemed the operative procedure was not preferred for any conservative approach however the study has shown an in depth feasibility study to affirm such findings in order to inform on policy or management paradigim shift. CONCLUSIONS There is need for further intervention in the management of femur fracture which complicates to poor knee joint function

scholarly journals Traffic Inequality and Relations in Maritime Silk Road: A Network Flow Analysis

2021 ◽  
Vol 10 (1) ◽  
pp. 40
Author(s):  
Naixia Mou ◽  
Haonan Ren ◽  
Yunhao Zheng ◽  
Jinhai Chen ◽  
Jiqiang Niu ◽  
...  
Keyword(s):  
Traffic Flow ◽  
Network Flow ◽  
Road Traffic ◽  
Flow Analysis ◽  
Silk Road ◽  
Identification System ◽  
Traffic Network ◽  
Trajectory Data ◽  
Maritime Traffic ◽  
Maritime Silk Road

Maritime traffic can reflect the diverse and complex relations between countries and regions, such as economic trade and geopolitics. Based on the AIS (Automatic Identification System) trajectory data of ships, this study constructs the Maritime Silk Road traffic network. In this study, we used a complex network theory along with social network analysis and network flow analysis to analyze the spatial distribution characteristics of maritime traffic flow of the Maritime Silk Road; further, we empirically demonstrate the traffic inequality in the route. On this basis, we explore the role of the country in the maritime traffic system and the resulting traffic relations. There are three main results of this study. (1) The inequality in the maritime traffic of the Maritime Silk Road has led to obvious regional differences. Europe, west Asia, northeast Asia, and southeast Asia are the dominant regions of the Maritime Silk Road. (2) Different countries play different maritime traffic roles. Italy, Singapore, and China are the core countries in the maritime traffic network of the Maritime Silk Road; Greece, Turkey, Cyprus, Lebanon, and Israel have built a structure of maritime traffic flow in the eastern Mediterranean Sea, and Saudi Arabia serves as a bridge for maritime trade between Asia and Europe. (3) The maritime traffic relations show the characteristics of regionalization; countries in west Asia and the European Mediterranean region are clearly polarized, and competition–synergy relations have become the main form of maritime traffic relations among the countries in the dominant regions. Our results can provide a scientific reference for the coordinated development of regional shipping, improvement of maritime competition, cooperation strategies for countries, and adjustments in the organizational structure of ports along the Maritime Silk Road.

scholarly journals Key Challenges in the Status Analysis for the Sustainable Urban Mobility Plan in Podgorica, Montenegro

2021 ◽  
Vol 13 (3) ◽  
pp. 1037
Author(s):  
Radoje Vujadinović ◽  
Jelena Šaković Jovanović ◽  
Aljaž Plevnik ◽  
Luka Mladenovič ◽  
Tom Rye
Keyword(s):  
Traffic Accidents ◽  
Road Traffic ◽  
Motor Vehicles ◽  
Urban Mobility ◽  
Passenger Cars ◽  
Study Program ◽  
Wide Range ◽  
The Status ◽  
Sustainable Urban Mobility ◽  
Status Analysis

The paper presents the results of the application of a practical approach for collecting data, which provides a simple, cost efficient, and easily reproducible method that was applied to obtain the necessary data for the status analysis of the Sustainable Urban Mobility Plan (SUMP) for Podgorica, the capital of Montenegro. Important data for the estimation of the existing condition of the traffic system were collected through desk research from the appropriate institutions and organizations. Several surveys and focus group interviews were conducted, in which about 5000 residents of Podgorica participated. In addition to answering questions, residents made numerous suggestions, confirming the correctness of a participatory approach in the new traffic planning paradigm that provides the SUMP with crucial advantages. A manual cordon count of traffic on five bridges for the traffic of the motor vehicles, as well as on two pedestrian-only bridges, was performed by students from the study program Road Traffic, and there are plans to repeat this in the coming years in order to enable more reliable monitoring and evaluation of the obtained data. Contemporary quality management tools such as BYPAD and ParkPAD were also used to assess the status of cycling and parking policy, respectively. It is especially important to emphasize that Podgorica is the first city in the West Balkans, and the fourth city in Europe, in which the ParkPAD tool was applied. A wide range of negative phenomena and trends was identified, like a rapid increase in the number of registered vehicles, an increase in the motorization rate and the number of traffic accidents, increased non-compliance with traffic rules, excessive use of passenger cars and auto-taxi vehicles, insufficient use of unattractive public transport, walking and cycling, etc. Based on the data collected, key challenges in status analysis in Podgorica were identified, which the SUMP should try to overcome.

scholarly journals Exploring the Distribution of Traffic Flow for Shared Human and Autonomous Vehicle Roads

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3425
Author(s):  
Huanping Li ◽  
Jian Wang ◽  
Guopeng Bai ◽  
Xiaowei Hu
Keyword(s):  
Traffic Flow ◽  
Autonomous Vehicles ◽  
Flow Model ◽  
Road Traffic ◽  
Autonomous Vehicle ◽  
Transformation Model ◽  
Hydrodynamic Theory ◽  
Traffic Flow Model ◽  
Traffic System ◽  
The Stability

In order to explore the changes that autonomous vehicles would bring to the current traffic system, we analyze the car-following behavior of different traffic scenarios based on an anti-collision theory and establish a traffic flow model with an arbitrary proportion (p) of autonomous vehicles. Using calculus and difference methods, a speed transformation model is established which could make the autonomous/human-driven vehicles maintain synchronized speed changes. Based on multi-hydrodynamic theory, a mixed traffic flow model capable of numerical calculation is established to predict the changes in traffic flow under different proportions of autonomous vehicles, then obtain the redistribution characteristics of traffic flow. Results show that the reaction time of autonomous vehicles has a decisive influence on traffic capacity; the q-k curve for mixed human/autonomous traffic remains in the region between the q-k curves for 100% human and 100% autonomous traffic; the participation of autonomous vehicles won’t bring essential changes to road traffic parameters; the speed-following transformation model minimizes the safety distance and provides a reference for the bottom program design of autonomous vehicles. In general, the research could not only optimize the stability of transportation system operation but also save road resources.

Long Short-Term Memory-Based Human-Driven Vehicle Longitudinal Trajectory Prediction in a Connected and Autonomous Vehicle Environment

2021 ◽  
pp. 036119812199347
Author(s):  
Lei Lin ◽  
Siyuan Gong ◽  
Srinivas Peeta ◽  
Xia Wu
Keyword(s):  
Traffic Flow ◽  
Short Term Memory ◽  
Road Traffic ◽  
Autonomous Vehicle ◽  
Trajectory Data ◽  
Road Transportation ◽  
Trajectory Prediction ◽  
Short Term ◽  
Term Memory ◽  
Long Short Term Memory

The advent of connected and autonomous vehicles (CAVs) will change driving behavior and travel environment, and provide opportunities for safer, smoother, and smarter road transportation. During the transition from the current human-driven vehicles (HDVs) to a fully CAV traffic environment, the road traffic will consist of a “mixed” traffic flow of HDVs and CAVs. Equipped with multiple sensors and vehicle-to-vehicle communications, a CAV can track surrounding HDVs and receive trajectory data of other CAVs in communication range. These trajectory data can be leveraged with recent advances in deep learning methods to potentially predict the trajectories of a target HDV. Based on these predictions, CAVs can react to circumvent or mitigate traffic flow oscillations and accidents. This study develops attention-based long short-term memory (LSTM) models for HDV longitudinal trajectory prediction in a mixed flow environment. The model and a few other LSTM variants are tested on the Next Generation Simulation US 101 dataset with different CAV market penetration rates (MPRs). Results illustrate that LSTM models that utilize historical trajectories from surrounding CAVs perform much better than those that ignore information even when the MPR is as low as 0.2. The attention-based LSTM models can provide more accurate multi-step longitudinal trajectory predictions. Further, grid-level average attention weight analysis is conducted and the CAVs with higher impact on the target HDV’s future trajectories are identified.

Travel mode recognition of urban residents using mobile phone data and MapAPI

2021 ◽  
pp. 239980832098300
Author(s):  
Zhenghong Peng ◽  
Guikai Bai ◽  
Hao Wu ◽  
Lingbo Liu ◽  
Yang Yu
Keyword(s):  
Urban Planning ◽  
Mobile Phone ◽  
Traffic Flow ◽  
Road Traffic ◽  
Urban Traffic ◽  
Phone Call ◽  
Traffic Information ◽  
Mobile Phone Data ◽  
Urban Residents ◽  
Travel Mode

Obtaining the time and space features of the travel of urban residents can facilitate urban traffic optimization and urban planning. As traditional methods often have limited sample coverage and lack timeliness, the application of big data such as mobile phone data in urban studies makes it possible to rapidly acquire the features of residents’ travel. However, few studies have attempted to use them to recognize the travel modes of residents. Based on mobile phone call detail records and the Web MapAPI, the present study proposes a method to recognize the travel mode of urban residents. The main processes include: (a) using DBSCAN clustering to analyze each user’s important location points and identify their main travel trajectories; (b) using an online map API to analyze user’s means of travel; (c) comparing the two to recognize the travel mode of residents. Applying this method in a GIS platform can further help obtain the traffic flow of various means, such as walking, driving, and public transit, on different roads during peak hours on weekdays. Results are cross-checked with other data sources and are proven effective. Besides recognizing travel modes of residents, the proposed method can also be applied for studies such as travel costs, housing–job balance, and road traffic pressure. The study acquires about 6 million residents’ travel modes, working place and residence information, and analyzes the means of travel and traffic flow in the commuting of 3 million residents using the proposed method. The findings not only provide new ideas for the collection and application of urban traffic information, but also provide data support for urban planning and traffic management.

scholarly journals Traumatic Liver Injury in Hong Kong: The Management Strategy and Outcome

2009 ◽  
Vol 16 (4) ◽  
pp. 208-216 ◽  
Author(s):  
CN Chong ◽  
YS Cheung ◽  
KF Lee ◽  
TH Rainer ◽  
BSP Lai
Keyword(s):  
Hong Kong ◽  
Liver Injury ◽  
Hospital Stay ◽  
Injury Severity ◽  
Road Traffic ◽  
Demographic Data ◽  
Operative Management ◽  
Concomitant Injuries ◽  
Significant Difference ◽  
Non Operative Management

Introduction Management of liver injury is challenging and evolving. The aim of this article is to review the outcome of traumatic liver injury in Chinese people in Hong Kong. Materials & methods Records of 40 patients with hepatic injury who received treatment at the Prince of Wales Hospital between December 2000 and May 2005 were reviewed. Demographic data, severity of liver injury, Injury Severity Score (ISS), haemodynamic status and Glasgow Coma Scale (GCS) score on admission, investigations made, concomitant injuries, management scheme, and outcome of patients were analysed. Results There were 23 male and 17 female patients with a mean age of 31.3 (SD=15.4) years. Road traffic accident was the most common injury mechanism (65%). Half of the patients were treated by non-operative management (NOM). None of them required surgery during subsequent management. Patients in the operative management (OM) group had a significantly higher ISS (p=0.026), but there was no significant difference in the mortality rate between the OM and NOM groups. Patients with stable haemodynamic status and who were treated non-operatively had a significantly shorter hospital stay (p=0.006). High grade liver injury (OR=8.0, 95% CI=1.2 to 53.8, p=0.03) and ISS greater than 25 (OR=21.6, 95% CI=2.0 to 225.3, p=0.01) were independent risk factors for mortality on multivariate analysis. Conclusions Non-operative management of liver injury can be safely accomplished in haemodynamically stable patients, with the possible benefit of a shorter hospital stay.

Measurement of reverberation time of a passenger car utilizing the wavelet filter bank

2005 ◽  
Vol 219 (3) ◽  
pp. 329-336 ◽  
Author(s):  
Sang-Kwon Lee ◽  
Dong-June Yu
Keyword(s):  
Filter Bank ◽  
Bandpass Filter ◽  
Wavelet Filter ◽  
Reverberation Time ◽  
Passenger Cars ◽  
Passenger Car ◽  
Concert Hall ◽  
Low Level ◽  
Wavelet Filter Bank

A few researchers have tried to find the measurement of the reverberation time of a passenger car. However, this has proved to be extremely difficult because the reverberation time of a passenger car is too short to measure using the traditional bandpass filter. If the reverberation time is very short, the product of the reverberation time ( T) and the bandwidth ( B) of the traditional bandpass filter is very small. The low level of the product BT required for the measurement of the reverberation time using the traditional bandpass filter is 16. In order to overcome this problem, the wavelet filter bank has been developed. In the paper, this new wavelet filter is employed to measure the reverberation times of five different classes of passenger car. The low level of the product BT required for the measurement of reverberation time using the wavelet filter is 4. Therefore, it was possible to measure the reverberation times of five passenger cars successfully using the new wavelet filter bank. It is found that the reverberation times measured in most passenger cars are around 0.04. It is a very short reverberation time compared with those of general acoustic rooms like a concert hall.

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