scholarly journals On the impact of connected automated vehicles in freeway work zones: a cooperative cellular automata model based approach

2018 ◽  
Vol 1 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Yun Zou ◽  
Xiaobo Qu
Keyword(s):  
Cellular Automata ◽  
Travel Time ◽  
Traffic Congestion ◽  
High Speed ◽  
Work Zones ◽  
Automated Vehicles ◽  
Cellular Automata Model ◽  
Content Type ◽  
Freeway Work Zones ◽  
The Impact

Purpose Freeway work zones have been traffic bottlenecks that lead to a series of problems, including long travel time, high-speed variation, driver’s dissatisfaction and traffic congestion. This research aims to develop a collaborative component of connected and automated vehicles (CAVs) to alleviate negative effects caused by work zones. Design/methodology/approach The proposed cooperative component is incorporated in a cellular automata model to examine how and to what scale CAVs can help in improving traffic operations. Findings Simulation results show that, with the proposed component and penetration of CAVs, the average performances (travel time, safety and emission) can all be improved and the stochasticity of performances will be minimized too. Originality/value To the best of the authors’ knowledge, this is the first research that develops a cooperative mechanism of CAVs to improve work zone performance.

scholarly journals Modeling and simulation of intersection quasi-moving block speed guidance based on connected vehicles

2020 ◽  
Vol 3 (2) ◽  
pp. 67-78
Author(s):  
Qing Xu ◽  
Jiangfeng Wang ◽  
Botong Wang ◽  
Xuedong Yan
Keyword(s):  
Traffic Congestion ◽  
High Speed ◽  
Connected Vehicles ◽  
Content Type ◽  
Communication Range ◽  
Proposed Model ◽  
Simulation Results ◽  
The Impact ◽  
Block Section ◽  
Guidance Model

Purpose This study aims to propose a speed guidance model of the CV environment to alleviate traffic congestion at intersections and improve traffic efficiency. By introducing the theory of moving block section for high-speed train control, a speed guidance model based on the quasi-moving block speed guidance (QMBSG) is proposed to direct platoon including human-driven vehicles and connected vehicles (CV) through the intersection coordinately. Design/methodology/approach In this model, the green time of the intersection is divided into multiple block intervals according to the minimal safety headway. Connected vehicles can pass through the intersection by following the block interval using the QMBSG model. The block interval is assigned dynamically according to the traveling relation of HV and CV, when entering the communication range of the intersection. To validate the comprehensive guidance effect of the proposed model, a general evaluation function (GEF) is established. Compared to CVs without speed guidance, the simulation results show that the GEF of QMBSG model has an obvious improvement. Findings Compared to CVs without speed guidance, the simulation results show that the GEF of QMBSG model has an obvious improvement. Also, compared to the single intersection speed guidance model, the GEF value of the QMBSG model improves over 17.1%. To further explore the guidance effect, the impact of sensitivity factors of the CVs’ environment, such as intersection environment, communication range and penetration rate (PR) is analyzed. When the PR reaches 75.0%, the GEF value will change suddenly and the model guidance effect will be significantly improved. This paper also analyzes the impact of the length of block interval under different PR and traffic demands. It is found that the proposed model has a better guidance effect when the length of the block section is 2 s, which facilitates traffic congestion alleviation of the intersection in practice. Originality/value Based on the aforementioned discussion, the contributions of this paper are three-fold. Based on the traveling information of HV/CV and the signal phase and timing plans, the QMBSG model is proposed to direct platoon consisting of HV and CV through the intersection coordinately, by following the block interval assigned dynamically. Considering comprehensively the indexes of mobility, safety and environment, a GEF is provided to evaluate the guidance effect of vehicles through the intersection. Sensitivity analysis is carried out on the QMBSG model. The key communication and traffic parameters of the CV environment are analyzed, such as path attenuation, PR, etc. Finally, the effect of the length of block interval is explored.

Impacts of high-speed railway on the industrial pollution emissions in China

Kybernetes ◽  
2020 ◽  
Vol 49 (11) ◽  
pp. 2713-2735 ◽  
Author(s):  
Xiaomin Fan ◽  
Yingzhi Xu ◽  
Yongqing Nan ◽  
Baoli Li ◽  
Haiya Cai
Keyword(s):  
Environmental Effects ◽  
Industrial Pollution ◽  
High Speed ◽  
Assessment Method ◽  
Economic Effects ◽  
High Speed Railway ◽  
Central Cities ◽  
Content Type ◽  
Pollution Emissions ◽  
The Impact

Purpose The purpose of this paper is to analyse the impact of high-speed railway (HSR) on industrial pollution emissions using the data for 285 prefecture-level cities in China from 2004 to 2016. Design/methodology/approach The research method used in this paper is the multi-period difference-in-differences (DID) model, which is an effective policy effect assessment method. To further address the issue of endogeneity, the DID integrated with the propensity score matching (PSM-DID) approach is employed to eliminate the potential self-selection bias. Findings The results show that the HSR has significantly reduced industrial pollution emissions, which is validated by several robustness tests. Compared with peripheral cities, HSR exerts a greater impact on industrial pollution emissions in central cities. In addition, the mechanism test reveals that the optimised allocation of inter-city industries is an important channel for HSR to mitigate industrial pollution emissions, and this is closely related to the location of HSR stations. Originality/value Previous studies have paid more attention to evaluating the economic effects of HSR, however, most of these studies overlook its environmental effects. Consequently, the impact of HSR on industrial pollution emissions is led by using multi-period DID models in this paper, in which the environmental effects are measured. The results of this paper can provide a reference for the pollution reduction policies and also the coordinated development of economic growth and environmental quality.

scholarly journals Examining partial proportional odds model in analyzing severity of high-speed railway accident

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jing Wang ◽  
Yinghan Wang ◽  
Yichuan Peng ◽  
Jian John Lu
Keyword(s):  
High Speed ◽  
Proportional Odds Model ◽  
Impact Factors ◽  
Proportional Odds ◽  
High Speed Railway ◽  
Severity Level ◽  
Content Type ◽  
Factors Affecting ◽  
Partial Proportional Odds Model ◽  
The Impact

Purpose The operation safety of the high-speed railway has been widely concerned. Due to the joint influence of the environment, equipment, personnel and other factors, accidents are inevitable in the operation process. However, few studies focused on identifying contributing factors affecting the severity of high-speed railway accidents because of the difficulty in obtaining field data. This study aims to investigate the impact factors affecting the severity of the general high-speed railway. Design/methodology/approach A total of 14 potential factors were examined from 475 data. The severity level is categorized into four levels by delay time and the number of subsequent trains that are affected by the accident. The partial proportional odds model was constructed to relax the constraint of the parallel line assumption. Findings The results show that 10 factors are found to significantly affect accident severity. Moreover, the factors including automation train protection (ATP) system fault, platform screen door and train door fault, traction converter fault and railway clearance intrusion by objects have an effect on reducing the severity level. On the contrary, the accidents caused by objects hanging on the catenary, pantograph fault, passenger misconducting or sudden illness, personnel intrusion of railway clearance, driving on heavy rain or snow and train collision against objects tend to be more severe. Originality/value The research results are very useful for mitigating the consequences of high-speed rail accidents.

Does opening high-speed railways affect the cost of debt financing? A quasi-natural experiment

2020 ◽  
Vol 10 (4) ◽  
pp. 473-496
Author(s):  
Hongling Guo ◽  
Keping Wu
Keyword(s):  
High Speed ◽  
Geographical Location ◽  
Debt Financing ◽  
Cost Of Debt ◽  
High Speed Railway ◽  
Content Type ◽  
Financing Cost ◽  
Debt Market ◽  
The Cost ◽  
The Impact

PurposeThis study aims to investigate how opening high-speed railways affects the cost of debt financing based on China's background.Design/methodology/approachUsing panel data on Chinese listed firms from 2008 to 2017, this study constructs a quasi-natural experiment and adopts a difference-in-difference model with multiple time periods to empirically examine the relation between the high-speed railway openings and debt financing cost.FindingsOur results show that opening high-speed railways reduces the cost of debt financing, and this negative correlation is more significant in non-state firms, firms with weaker internal control, and firms that hire non-Big Four auditors. Besides, we explore the impact mechanisms and find that opening high-speed railways improves analyst attention, institutional investor participation, and information disclosure quality, which in turn lowers the cost of debt financing.Research limitations/implicationsThe results imply that the opening of high-speed railways helps to alleviate the information asymmetry and adverse selection between firms and creditors and ultimately reduces the cost of corporate debt financing.Practical implicationsThis paper can inform firms and stakeholders about the impact of opening high-speed railways on debt financing cost: it improves the information environment, reduces the geographical location restrictions of debt financing, ensures the reasonable pricing of corporate debt, and thus promotes the healthy and sound development of the debt market.Originality/valueThis paper provides theoretical support and empirical evidence for the impact of infrastructure construction on the information environment of the debt market in China, which enriches the research on the “high-speed railway economy.” In addition, as an exogenous event, the opening of high-speed railways instantly shortens the time distance between firms and external stakeholders, which gives us a natural environment to conduct empirical research, thus providing a new perspective for financial research on firms' geographical location.

The impact of order imbalance on returns, liquidity, and volatility in agricultural commodity markets

2018 ◽  
Vol 78 (5) ◽  
pp. 571-591 ◽  
Author(s):  
Steffen Volkenand ◽  
Guenther Filler ◽  
Martin Odening
Keyword(s):  
Trading Volume ◽  
High Speed ◽  
Price Volatility ◽  
Agricultural Commodity ◽  
Content Type ◽  
Order Imbalance ◽  
New Information ◽  
Agricultural Futures ◽  
Best Offer ◽  
The Impact

PurposeThe purpose of this paper is to investigate and compare the impact of order imbalance on returns, liquidity and price volatility in agricultural futures markets on an intraday basis. The authors examine whether order imbalance is more powerful to explain variations in asset prices compared to other indicators of trading activity, particularly trading volume.Design/methodology/approachUsing Chicago Mercantile Exchange best bid best offer data, the impact of order imbalance is analyzed via regression analyses. The analyses are carried out for corn, wheat, soy, live cattle and lean hogs in March 2008 and March 2016.FindingsResults confirm the positive relation between order imbalance and returns as well as between order imbalance and price volatility as suggested by market microstructure models. Order imbalance, however, does not generally outperform trading volume as an explanatory variable.Practical implicationsFor some contracts, returns can be predicted using lagged order imbalance. This offers the opportunity to derive profitable trading strategies.Originality/valueThis paper is one of the first attempts to explore the relationship between order imbalance and returns, liquidity and volatility for agricultural commodity futures on an intraday basis, accounting for the increased trading volume and for the high speed at which new information enters the market in an electronic trading environment.

scholarly journals COVID-19 lockdown in Poland – changes in regional and local mobility patterns based on Google Maps data

2020 ◽  
Vol 23 (2) ◽  
pp. 46-55
Author(s):  
Maciej Tarkowski ◽  
Krystian Puzdrakiewicz ◽  
Joanna Jaczewska ◽  
Marcin Połom
Keyword(s):  
Travel Time ◽  
Traffic Congestion ◽  
High Speed ◽  
Spatial Diversity ◽  
Local Context ◽  
Mobility Patterns ◽  
Social Distancing ◽  
Scientific Discussion ◽  
Initial Correlation ◽  
Local Mobility

As no effective treatment or vaccine have yet been developed, the only way to prevent the spread of SARS-Cov-2 is to introduce social distancing measures. Scientific discussion regarding their actual effectiveness and socio-economic consequences has only just begun. Both declining mobility and changes in mobility patterns are obvious effects of social distancing. The main objective of this article is to present spatial diversity of changes in regional and local mobility in Poland with the use of data gathered and provided by Google LCC. As for the regional dimension, the mobility has declined steadily in most of the analysed areas. The regional changes were more visible only in the case of the following categories of areas: grocery & pharmacy and parks. The initial correlation analysis has shown that distribution of those changes more or less reflects spatial voting patterns. Both historical and cultural factors may explain such results, including ingrained habits, collective attitudes towards politics and group values. In the local context, illustrated by the analysis of changes in travel time from housing areas in Gdańsk, Gdynia and Sopot to the business and science centre in Gdańsk-Oliwa, a noticeable yet spatially diversified decrease in drive time (by private car) has been observed. The most significant reduction in travel time was recorded in peripheral areas accessible by high-speed roads which are normally jammed during peak hours. The mobility constraints have led to highly reduced traffic congestion, and consequently, shortened the travel time.

scholarly journals Identify Optimal Traffic Condition and Speed Limit for Hard Shoulder Running Strategy

2021 ◽  
Vol 13 (4) ◽  
pp. 1822
Author(s):  
Fan Yang ◽  
Fan Wang ◽  
Fan Ding ◽  
Huachun Tan ◽  
Bin Ran
Keyword(s):  
Cellular Automata ◽  
Traffic Congestion ◽  
Traffic Management ◽  
Clustering Algorithm ◽  
Mean Shift ◽  
Management Strategies ◽  
Speed Limit ◽  
Clustering Methods ◽  
Traffic Condition ◽  
Cellular Automata Model

Highway system is experiencing increasing traffic congestion with fast-growing number of vehicles in metropolitan areas. Implementing traffic management strategies such as utilizing the hard shoulder as an extra lane could increase highway capacity without extra construction work. This paper presents a method of determining an optimal traffic condition and speed limit of opening hard shoulder. Firstly, the traffic states are clustered using K-Means, mean shift, agglomerative and spectral clustering methods, and the optimal clustering algorithm is selected using indexes including the silhouette score, Davies-Bouldin Index and Caliski-Harabaz Score. The results suggested that the clustering effect of using K-Means method with three categories is optimal. Then, cellular automata model is used to simulate traffic conditions before and after the hard shoulder running strategy is applied. The parameters of the model, including the probabilities of random deceleration, slow start and lane change, are calibrated using real traffic data. Four indicators including the traffic volume, the average speed, the variance of speed, and the travel time of emergency rescue vehicles during traffic accident obtained using the cellular automata model are used to evaluate various hard shoulder running strategies. By using factor analysis and TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) methods, the optimal traffic condition and speed limit of opening hard shoulder could be determined. This method could be applied to highway segments of various number of lanes and different speed limits to optimize the hard shoulder running strategy for highway management.

Design of reversible Feynman and double Feynman gates in quantum-dot cellular automata nanotechnology

Circuit World ◽  
2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sadat Riyaz ◽  
Vijay Kumar Sharma
Keyword(s):  
Cellular Automata ◽  
Quantum Dot ◽  
Cell Count ◽  
High Speed ◽  
Xor Gate ◽  
Content Type ◽  
Quantum Dot Cellular Automata ◽  
Logical Operations ◽  
Feynman Gate ◽  
Exclusive Or

Purpose This paper aims to propose the reversible Feynman and double Feynman gates using quantum-dot cellular automata (QCA) nanotechnology with minimum QCA cells and latency which minimizes the circuit area with the more energy efficiency. Design/methodology/approach The core aim of the QCA nanotechnology is to build the high-speed, energy efficient and as much smaller devices as possible. This brings a challenge for the designers to construct the designs that fulfill the requirements as demanded. This paper proposed a new exclusive-OR (XOR) gate which is then used to implement the logical operations of the reversible Feynman and double Feynman gates using QCA nanotechnology. Findings QCA designer-E has been used for the QCA designs and the simulation results. The proposed QCA designs have less latency, occupy less area and have lesser cell count as compared to the existing ones. Originality/value The latencies of the proposed gates are 0.25 which are improved by 50% as compared to the best available design as reported in the literature. The cell count in the proposed XOR gate is 11, while it is 14 in Feynman gate and 27 in double Feynman gate. The cell count for the proposed designs is minimum as compared to the best available designs.

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