A robust ant colony metaheuristic for urban freight transport scheduling using passenger rail network

Consolidating passenger and freight transportation in an urban–rural transit system

In order to solve the optimization of new energy bus line network, a new energy bus line network based on ant colony algorithm and low-carbon concept is proposed. Firstly, the model of public transport network is established combined with OD matrix, and the improved ant colony algorithm is used to iteratively optimize the initial suboptimal route set, optimize the objective function, and finally obtain the optimal public transport route set. Secondly, the improved ant colony algorithm based on simulated annealing solves the design of public transport network, and the optimization scheme greatly reduces the number of passenger transfers and the total travel time of passengers. Finally, simulated annealing algorithm, basic ant colony algorithm, and simulated annealing improved ant colony algorithm are used to optimize the objective function. It is proved that the improved ant colony algorithm of simulated annealing can find the optimal solution of the three algorithms when solving the problem of public transport network design, which is better than the solution of basic ant colony and simulated annealing algorithm. The solution efficiency is 10.6 times that of simulated annealing algorithm and 3.5 times that of basic ant colony algorithm.

VIVER -- A Sustainable Transport Vision for Germany

The cutting and sewing process is a traditional flow shop scheduling problem in the real world. This two-stage flexible flow shop is often commonly associated with manufacturing in the fashion and textiles industry. Many investigations have demonstrated that the ant colony optimization (ACO) algorithm is effective and efficient for solving scheduling problems. This work applies a novel effective ant colony optimization (EACO) algorithm to solve two-stage flexible flow shop scheduling problems and thereby minimize earliness, tardiness, and makespan. Computational results reveal that for both small and large problems, EACO is more effective and robust than both the particle swarm optimization (PSO) algorithm and the ACO algorithm. Importantly, this work demonstrates that EACO can solve complex scheduling problems in an acceptable period of time.

Network Optimization of RPTB Express based on Ant Colony Algorithm

The three metropolitan regions, including Jing-Jin-Ji (JJJ), Yangtze River Delta (YRD) and Pearl River Delta (PRD), are the most developed regions of China. This study focuses on these three metropolitan regions and tries to estimate and analyze the structure and influencing factors of CO2 emissions from transport sector, including passenger and freight transport, simultaneously covering road, rail, and water transport. The results suggest that in the period of 2000–2013, the CO2 emissions from transport sector increased from 27.8 to 198.8 Mt in JJJ, from 29.7 to 163.5 Mt in YRD, and from 13.1 to 74.0 Mt in PRD. Comparatively speaking, JJJ had the highest CO2 emission intensity of freight and urban passenger transport as well as highest transport CO2 emissions per capita and per unit GDP, while PRD had the highest transport CO2 emissions per hectare. The main challenge of reducing CO2 emissions from transport sector in these regions stemmed from freight transport and road transport. Based on decomposition analysis, economic welfare was the most important driving force of the CO2 emissions growth in all three regions, followed by transport type mix, transport dependence and modal energy intensities. In the future, low-carbon transport strategies about controlling the growth of transport demand, adjusting the transport modal structure and improving the modal energy efficiency and fuel emission efficiency are needed in all three regions, and each region should have slightly different focus. The JJJ region needs to emphasize adjusting transport modal structure, the YRD region needs to emphasize improving modal energy efficiency, and the PRD region needs to focus more on controlling the growth of transport dependence.

Based on the associated network of passenger and freight transport in the New Western Land-Sea Corridor, the structure and characteristics of passenger and freight transport network in different years are analyzed using passenger volume and freight volume, and the resilience of the network is analyzed using the disturbance model. Finally, the coordinated development of passenger transport and logistics is discussed by applying a coupling coordination model. The results show that, from 2000 to 2018, the New Western Land-Sea Corridor has realized the evolution of the spatial pattern of passenger transport network from “two center and numerous branches” to “three centers and three auxiliaries”. Moreover, the evolution of the spatial pattern of the freight transport network changed from “two centers and one auxiliary” to “one center and multiple auxiliaries”. In terms of network tenacity, the disturbance strategy based on node degree value has the strongest damage to the performance of passenger and freight transport networks. The coupling coordination value is gradually rising from a low level and finally develops to an ordered trend. Therefore, it is proposed that passenger transport development could be supported from the “growth pole” and “zone” development modes, while the logistics development would adopt the “axis” development pattern and focus on the protection of the vital city nodes in the corresponding network. In this way, it can realize the effective connection of multiple paths, improve the tenacity of network and boost hub economy, consummate the regional coordination mechanism, and finally promote the advancement of the New Western Land-Sea Corridor.

Improving the quality of passenger services provided by mass transit is one of the most important areas in meeting the needs of society. People's standard of living depends on the quality of urban transportation services. In a market economy, mass transit users determine their satisfaction with the transportation services through various surveys. The surveys are a valuable source of information on the urban passenger transportation operational status and are usually organized in the form of questionnaires. At the same time, the questionnaire development errors can affect the study results and lead to incorrect conclusions. Consequently, the questionnaire reliability is important directly from the developing stage. The questionnaire reliability is the reproducibility of the study results and their resistance to the random factors interference. The questionnaire design inaccuracy should be eliminated by using statistical packages to assess the questionnaire content quality and calculate the Cronbach's alpha. From the coefficient values, it is possible to make a decision on the questionnaire internal consistency, its compliance with the purpose, reliability and application in practical work. Thus, the study used well-known statistical data processing packages such as MS Office Excel, Statgraphics Centurion, IBM SPSS and Statistica. A test sample of 20 respondents was used to check the questionnaire reliability and the respondents' opinion related to the passenger transportation quality components. In general, all data processing packages were suitable for calculating the alpha coefficient. From the all software considered, Statistica was the most functional due to wide range of helping tools while improving and evaluating a survey form, and MS Office Excel was the least functional since most calculations had to be performed manually. In the Statistica environment, simulating the number of questions and the value of alpha allows significant increasing the questionnaire quality. The results of the statistical analysis showed the questionnaire was quite reliable – from 0.763 to 0.771. According to passengers, the most important factors to generate the transportation quality were the travel cost, travel time, and passenger safety, and the least important are the service culture and the vehicle appearance. Further research should be aimed at developing and evaluating more comprehensive surveys on other features of passenger and freight transportation, and logistics.

The current socio-economic conditions of some developed and developing countries are not favorable for the development of the public mass transport services. Most of the residents of large and medium-sized cities, but also smaller towns, use their own passenger car on mandatory trips. This phenomenon perfectly reflects the constantly growing of motorization index in such countries. The consequence of this is, of course, the decreasing number of passengers carried by means of public mass transport, in particular operating outside of large urbanized areas. This causes and unfortunately will cause not only further problems of automotive congestion on the transport networks of urban areas, reduction of the road safety level, but also adverse environmental effects in the form of pollution. The authors of the article analyzed the results of transport surveys, which were carried out in recent years among the public transport passengers. The surveys concerned the assessments and postulates and expectations of passengers. The research was carried out in one of the typical in terms of socio-economic conditions of Polish voivodships (a country dynamically developing in the passenger transport sector, in terms of both mobility, as well as the quantitative and qualitative status of transport means and transport infrastructure). The voivodship subjected to such analysis was the Kuyavian-Pomeranian Voivodship, located in the central part of Poland. The respondents were asked to speak on topics related to, among others, transport infrastructure, means of transport, access to services of public transport systems, comfort and safety of traveling. The analysis also included assessments and postulates related to tariff systems, travel information systems, and transport integration systems - functioning in the voivodship. The results of the research were analyzed by the rail passenger transport and bus passenger transport as part of the voivodship public transport system. In the majority of cases, passengers’ assessments were not satisfactory. The most frequently issued evaluations fluctuated only around the average (on a scale from 1 to 10). The authors have thoroughly analyzed the results of the transport survey, confronting the results obtained and trying to find out their causes depending on the characteristics of the area under analysis.

The intensity of traffic flows increases every year and intensifies its impact significantly on urban territory's ecologic situation and natural environment. In Ukrainian cities, the growth of noise pollution is quite a topical problem as it has a significant impact on the environment because of the increase in car numbers. Traffic flow intensity and densification of the built-up area cause the increase of the noise level. As analytical methods of calculation of determination of traffic noise level have several disadvantages, then for assessing the level of noise on arterial streets of Lviv city, research is carried out with consideration of traffic flow indicators. One of the critical criteria that have an impact on noise pollution in the urban environment is traffic flow composition. Conducted research indicates that the speed of traffic flow creates significant noise pollution, especially on those streets where cobblestone is a road pavement. Freight and passenger transport that moves along arterial streets causes the increase of noise level and increases its impact on the city territory. On sections of arterial streets in peak periods of the day with high values of volume-capacity ratio and general share of freight and public transport of more than 30% in a flow, the noise exceeds the acceptable norms and has a harmful impact on the environment. That is why it is necessary to assess noise pollution and the development of protection measures from noise during the planning and construction of some urban regions or residential areas. It is established that to lower the noise level on streets, it is necessary to consider existing intersections of arterial streets and the regime of movement on them. To lower transport noise, it is necessary to distribute freight and transit transport by city streets more rationally, use qualitative public transport, and limit the maximal speed regime on city streets. Further research on the road network will provide an opportunity to assess the noise level distribution of traffic flows in Lviv city. It will help to determine the problem places and propose methods of combating traffic noise.

Cutter head is one of the most important components for the full-face rock tunnel boring machine (TBM), in which the layout design of the disc cutters is a key issue. Considering the complex engineering technical requirements, this paper studied an ant colony optimization (ACO) algorithm to solve the disc cutters plane layout problem. The searching space of the design variables (disc cutters’ position) were dispersed by setting several different search steps, then an ACO algorithm was adopted to search the best searching step of each design variable dynamically during the whole optimization process. Finally, the disc cutters layout design instance was solved by the ACO method to demonstrate its feasibility and effectiveness. The computational results showed that that ACO method can provide various disc cutters layout schemes for engineers choosing from.KeywordsFull-face tunnel boring machineDisc cutterslayoutAnt Colony Optimization

Abstract. With the advancement of urbanization, urban-rural public transport issues have become one of the most critical issues in urban development. The paper makes a detailed study on the optimization of urban-rural bus routes in Erqi District of Zhengzhou, China. The factors of bus stop selection are analyzed, and the three categories, including traffic road condition factors, economic benefit factors and waiting number factors, are mainly considered. The analytic hierarchy process is used to determine 35 specific objectives of urban-rural bus stop optimization, 20 of which are selected for simulation experiment with large weight. Then the ant colony optimization (ACO) algorithm in path optimization is analyzed, which has the following two advantages. First, the global pheromone update is combined with the local pheromone update to enhance the algorithm's optimization ability and convergence speed. Second, through the method of spatial contraction transformation, the ant constructs a solution to reduce the number of construction steps and speed up the operation. Based on the actual analysis of urban-rural public transportation in the Erqi District of Zhengzhou, a simulation experiment is executed to show that the ACO algorithm is able to find out the optimal path, which is 15.1% shorter than the ant colony system (ACS) algorithm. The ACO algorithm improved path planning has good time effectiveness and path practicability.

In this work, we present an extension of the generalized covering salesman problem as distance constrained generalized m-covering salesman problem. Given a set of vertices including a depot, facilities, customer locations and demand associated with each customer location, the objective is to determine an optimal tour of each salesman such that the total covered demand is maximized and the tour length is minimized. A bi-objective mixed-integer programming model is formulated for the problem. The proposed model is solved using GUROBI 8.0 solver’s in-built hierarchical optimization approach. However, the computational complexity of the problem demands a specialized solution approach. To solve the problem efficiently, we propose two metaheuristics ant colony optimization (ACO) algorithm and greedy randomized adaptive search procedure (GRASP). Extensive computational experiments were performed using the benchmark instances from the literature. The results of computational experiments show the efficiency and effectiveness of the proposed metaheuristics algorithms. Although, the GRASP metaheuristics outperform the ACO algorithm in case of medium and large size instances.

Vehicle automation is one of the most researched topics in transport studies but much remains uncertain about the speed of adoption and potential impacts, including if and how it can contribute to greater environmental sustainability. This study adopts a Delphi approach to examine the speed with which 15% of new vehicles will be automated (SAE-3, SAE-4 or SAE-5) and what impacts automation may have on motility, mobility, resource use and externalities in both passenger and freight transport. Although challenges with recruitment mean that all findings must be caveated and seen as exploratory, the analysis demonstrates considerable dissensus regarding the expected speed and impacts of vehicle automation in both passenger and freight transport among the participants. For both aspects, a diversity of views remains once participants were informed about the expectations of other panellists. The range of views is organised around the axes of optimism and certainty about what may happen. Considerable differences between passenger and freight transport can be identified for potential impacts of vehicle automation but not for speed of adoption.

Due to the emerging of modern evolution of the Fifth Generation (5G) wireless technology and the growth of data traffic to meet various communication requirements of future applications. Routing and path planning in 5G wireless networks is one of the challenges brought about by the variation of network features like traffic load and topology which may differ in stochastic and time varying manner. However, as the mobile users' growth, there is a need to efficient routing strategy for shortest path to forward user requests to the servers to reach services. To meet this aim, an adaptive Meta-heuristic Ant Colony Optimization (ACO) algorithm has proposed in this paper. ACO based on swarm intelligence techniques that has considered inspired algorithm by imitating the sociological attitude related to ants crowd. ACO like the other evolutionary algorithms based on population; it initiates with random solutions of the population. This work was implemented using NS3 simulation tool with different scenarios and parameters. The computational results have shown that the ACO method is better to find the optimal solution in 5G networks than the traditional inelastic way. The simulation outcome indicates the efficiency of the proposed method where the packet delivery ratio increased while the drop packets ratio and the transmission delay reduced.