Line Planning Research Articles

Combined line planning and train timetabling for strongly heterogeneous railway lines with direct connections

Rail systems have been developing rapidly in recent years aiming at satisfying the growing passenger demand and shortening passenger travel time. The line planning problem (LPP) and train timetabling problem (TTP) are two key issues at the strategic level and tactical level, laying the foundation of a high-level service quality for railway operation. In this paper, a multi-frequency LPP (MF-LPP) model and a multi-period TTP (MP-TTP) model are introduced for direct connections, with consideration of both periodic and aperiodic nature to meet strongly heterogeneous train services and reduce the capacity loss of train operating companies. A combined LPP and TTP method is designed considering timetable robustness, timetable regularity, and passenger travel time. For a given line pool, a multi-objective mixed integer linear programming model for the MF-LPP is formulated to obtain a line plan with multiple line frequencies by minimizing travel time, empty-seat-hour and the number of lines. Using the acquired line plan from the previous step, a MP-TTP model is proposed to achieve the minimal travel time, the maximal timetable robustness and the minimal number of overtakings. The two models work iteratively with designed feedback constraints to find a better plan for the rail transport system. Numerical experiments are applied to verify the performance of the proposed model and solution approach.

An Integrated Model for Demand Forecasting and Train Stop Planning for High-Speed Rail

Studying the interaction between demand forecasting and train stop planning is important, as it ensures the sustainable development of high-speed rail (HSR). Forecasting the demand for high-speed rail (HSR), which refers to modal choice or modal split in this paper, is the first step in high-speed rail (HSR) planning. Given the travel demand and the number of train trips on each route, the train stop planning problem (TSPP) of line planning involves determining the stations at which each train trip stops, i.e., the stop-schedule of each train trip, so that the demand can be satisfied. To integrate and formulate the two problems, i.e., the modal choice problem (MCP) and train stop planning problem (TSPP), a nonlinear model is presented with the objective of maximizing the total demand captured by a high-speed rail system. To solve the model, a heuristic iterative algorithm is developed. To study the relationship between the demand and the service, the Beijing–Shanghai high-speed rail (HSR) corridor in China is selected. The empirical analysis indicates that combining modal choice and train stop planning should be considered for the sustainable design of high-speed rail (HSR) train services. Furthermore, the model simulates the impact of the number of stops on its mode share by reflecting changes in travelers’ behaviors according to HSR train stop planning, and it also provides a theoretical basis for the evaluation of the adaptability of the service network to travel demand.

A Multiobjective Integer Linear Programming Model for the Cross-Track Line Planning Problem in the Chinese High-Speed Railway Network

In China, cross-track high-speed trains (CTHSTs) play an important role in railway passenger transportation, with an increasing number of cross-track passengers sourced from the expansion of high-speed railway (HSR) network. The CTHST generally has long travel times, so running CTHSTs is not beneficial for train rescheduling work and plan’s periodicity in the periodic operation context. Thus, the main challenge in cross-track line planning is looking for a symmetry point between passenger transportation and disadvantages of running CTHSTs, which are two conflicting aspects. In this study, we developed a multiobjective integer programming model to produce a balanced cross-track line plan by combining individual-track high-speed trains (ITHSTs) into CTHSTs, which is a discrete optimization problem. This strikes a balance among four goals: the periodicity of the line plan, CTHST quantity, CTHST mileage, and CTHST stops in the context of periodic operation, while satisfying the constraints of passenger demand and the number of available ITHSTs. Numerical experiments are conducted based on a real-world network and optimal solutions were quickly obtained. We analyzed impacts of each goal and parameter on the result and influencing factors of computation. Comparisons with existing methods and real-life plans were also presented to show improvements made by proposed model.

Efficiency and Spatial Equity Impacts of High-Speed Rail on the Central Plains Economic Region of China

Efficiency impacts can be assessed based on improvements in accessibility promoted by the high-speed rail (HSR) project, focusing mainly on major urban areas. Spatial equity impacts originate from changes in the distribution of accessibility levels observed across such cities. This study uses the weighted average travel time and coefficient of variation to explore the impact of HSR on efficiency and spatial equity within the Central Plains Economic Region (CPER) and to build an “efficiency-equity” model to identify optimal upgrading of conventional rail (CR) lines to improve the accessibility of the CPER and mitigate regional disparities. The results indicate that since the operation of HSR, accessibility levels across the CPER have improved by roughly 24.56%, and the spatial distribution of gains has been uneven since the most significant improvements have occurred in HSR cities and large cities. Inequality in regional accessibility has increased by 28.12%, creating a more heterogeneous pattern of accessibility. With goals of “efficiency” and “equity”, an examination of the upgrading of CR as an approach shows that “Xinxiang-Jiaozuo” and “Xinxiang-Jiaozuo-Sanmenxia-Yuncheng” are the best upgraded lines for improving the efficiency of the CPER and limiting regional disparities. The results of this study serve as supportive information for the planning and construction of HSR lines and networks and for underdeveloped regional transport system policymaking.

The Role of trade Transport Routes in Economic Growth throughout History in Bisha Province: A Historical and Analytical Study

Background/Objectives: To identify the role of trade transport routes in economic growth throughout history in Bisha Province. Methods/Statistical Analysis: The study followed two approaches; the first one is the historical approach, which seeks to study the ancient and historical phenomena and linking them with the current problems. The second approach is the analytical approach to analyze the documents that related to the subject matter of the study, and data extraction that may contribute in answering the main question of the study. The study concluded that ‘Asir Region publically and Bisha Province privately were linked together with a strong cultural linkage with the kingdoms of South Arabian Peninsula. Bisha Province has an important historical presence, as it is one of the richest places with heritage and archaeological places. Two trade routes were famous in Arabian Peninsula that connects eastern and western sides of Asia; these trade routes are Incense trade route and Al Hareer Route. Bisha was one of the most important trade routes passages that came from south to north in its way to the civilization of Mesopotamia, The Levant, Egypt and the Mediterranean Sea. The paper used 26 of previous studies as references. Findings: We found on the sides of the trade routes of Wadi Bisha the emergence of stations and trade centers that have been developed into villages and cities where people were aggregated along the trade route to provide service to the conveys in terms of food and drink also they act as a trade guide. Researchers mentioned that Bisha Province and its villages and cities, were an old and thriving Arab town, because it is located along the southern sector of the path of the historical Incense pathway that was linking the cultural centers at the south and the north of Arabian Peninsula together. The region seems to get a great benefit from this trade so markets are spread. People got rich and they got benefit from this in reclamation and cultivation of their lands. They build dams and facilitate the methods to get benefits from valleys’ water, however most of them extinct as a result of time factors where future archaeological scans may result in a clearer picture of these sites. Bisha has an important role in successive Islamic ages due to its strategic location on the trade routes and on Yemeni Hajj routes, it is known by highest Yemeni Hajj route or known by Najdian Hajj route that links between San’a in Yemen with Makkah in Hejaz. Bisha and its cities related closely to transportation and tribe’s movement even it is a trade tribe or a Hajj tribe, the fertile soil and abundant water in the tribe stations had been helped in the flourishing of these routes. Improvements/Applications: The study had recommended the importance of studying historical economic diversity in Bisha Province, as well as the possibility of benefiting from this study in the future planning of the railway lines that could be operated in the region, based on the old routes that have been tracked according to its facility and simplicity. Keywords: ‘Asir Region, Bisha Province, Historical Approach, Trade in Ancient Times, Trade Routes, Wadi Bisha

Menentukan Nilai Penggantian Wajar Lahan Terdampak Pekerjaan Reaktifasi Jalur Kereta Api Trase Muaro Logas, Kabupaten Sijunjung, Provinsi Sumatera Barat

Abstract – The calculation of the value of the Reasonable Land Turnover Terdamapak Job Reaktifasi railway line for arbitration was Muaro Logas was part of the study of the action of liberation/land and buildings for the reform plan of the reaktifasi railway line between Muaro-Logas is part of the planning of the reactivation railway line. This study analyzes regulations and policies, perceived an inventory and survey/census by identifying the affected community land procurement, with regard to the characteristics and the types of harm experienced, agreement agreement between the local government, the province and the Center in funding the acquisition of land; analyze optimum land procurement and analyse livelihood for the population affected by socio-economic factors, analyzing the parameters with the social, cultural, and economic related to population, the impact of the procurement of land and influence implementation of the work against the poor, residents of the tribal minorities, alienated, and other vulnerable groups, including women, as well as the institutional framework in planning the liberation of land and the settlements back including duties and responsibilities each institution. In the calculation of the Reasonable Replacement Value using Standar Penilaian Indonesia306 (SPI 306) about the assessment of the provision of Land for development for the benefit of the public

Accuracy of Location Currency and Processing of Received Data on International Transport Corridors and High-Speed Masters

The main stages of geodetic survey of the railway are considered, both in the new construction and in the reconstruction of existing sites. The analysis of the line plan on curves and direct sections of the railways of Ukrainian international transport corridors is given. Calculations are made on the method of recording the accuracy of measurements at high speed and extra-high speed, confi rmed the need to take into account the type of volumes of work, the establishment of rational parameters of the plan in accordance with the specifi ed levels of maximum speed.

A Line Planning Approach for High-Speed Rail Networks with Time-Dependent Demand and Capacity Constraints

In high-speed rail networks, trains are operated with high speeds and high frequencies, which can satisfy passenger demand with different expected departure times. Given time-dependent demand, this paper proposes a line planning approach with capacity constraints for high-speed rail networks. In this paper, a bilevel optimization model is formulated and the constraints include track section capacity per unit time, train seat capacity, and the gap between the number of starting trains and that of ending trains at a station. In the upper level, the objective is to minimize train operational cost and passenger travel cost, and the decision variables include the line of each train, carriage composition of each train, train stop patterns, train start times, and train arrival and departure times at stops in the line plan. In the lower level, a schedule-based passenger assignment method, which assigns time-varying demand on trains with seat capacity constraints by simulating the ticket-booking process, is used to evaluate the line plan obtained in the upper level. A simulated annealing algorithm is developed to solve the model in which some strategies are designed to search for neighborhood solutions, including reducing train carriages, deleting trains, adding trains, increasing train carriages, and adjusting train start times. Finally, an application to the Chinese high-speed rail network is presented. The numerical results show that (i) the average time deviations between the expected departure times and the actual boarding times of passengers are within 30 min, (ii) the unserved passengers are less than 200, and (iii) the average load factors of trains are about 70%. Hence, line plan solutions meet time-dependent demand well and satisfy the capacity constraints for high-speed rail networks.

Planning in four areas of the Vila Viva Program in the city of Belo Horizonte, Brazil: a documentary analysis.

The Vila Viva Program (PVV), a social policy integrated by activities of urbanization, social development and land regularization of Belo Horizonte in Minas Gerais (BH), has its shares planned through the Specific Global Plan (PGE), instrument of local diagnosis and definition of interventions. The aim of the study was the analysis of PGE of four localities in BH occupied in a disorderly manner by low-income population. The PGE were submitted to documental analysis, consisting of preliminary analysis and documents and content analysis, with evaluation of theoretical dimensions: physical environment, social, housing, community and public facilities, which refer to the conceptual model of the Urban Health and Installment Law, Occupation and use of BH soil. All localities were similar in theoretical dimensions analyzed. The participation of the population was provided in all stages of PGE and the major claims in the four locations were: health environment, opening and street paving, expansion of public transport, improvement of health and education equipment and land regularization. The proposal planning of PGE line is consistent with the theoretical reference of Urban Health and, above all, with the inclusive and integrative character of the PVV.

Value of energy storage for transmission investments

This paper investigates joint investment planning of transmission lines and energy storage. Energy storage can be seen as a complement to transmission infrastructure and can be used for transmission deferral. On the other hand, under certain conditions, when the expected profit of both sectors depends on congestion in the system, transmission and energy storage can be seen as competitors. The transmission sector is in this study assumed to be a natural monopoly and operation and planning of transmission lines is performed by an independent company whereas the energy storage owner company operates and invests under competitive market rules. Three main questions are addressed in this paper. First of all, will additional energy storage capacity contribute to the growth of social welfare? Second, how will incentive regulation of the transmission network affect the need for energy storage? Third, how will the choice of incentive regulation affect the value of energy storage. This paper first provides an overview of incentive regulation which can be applied to transmission investments. Then case studies based on a 6-node power system network and the IEEE 118-node system are proposed in order to answer the aforementioned questions. The results of the case studies show that energy storage investments complement transmission expansion and contribute to higher social welfare values. The benefits from energy storage investments are significantly higher under two investigated incentive regulations as compared to the case without incentive regulation. Thus, the transmission investment planning process should consider energy storage options.

Relationship between the anatomic structures and mandibular posterior teeth for endodontic surgery in a Turkish population: a cone-beam computed tomographic analysis.

The purpose of this study is to evaluate the relationship between anatomic structures and mandibular posterior region using cone-beam computed tomography (CBCT) in terms of endodontic surgery. A total of 150 CBCT images were used to investigate the proximity of the anatomical structures and the mandibular posterior teeth. The buccal and lingual bone thickness overlying each root, buccolingual, and mesiodistal dimension of the roots were measured at the level of 3mm apical resection, and the mental foramen (MF) distance to the premolar teeth and the distance of the mandibular canal (MC) to all the posterior teeth were measured. The thinnest part of the buccal cortical bone was measured in the first premolar teeth (1.70mm) and in the mesial root of the first molar (2.25mm) while the thickest region was measured in the distal root of the second molar tooth (6.95mm). The maximum amount of substance to be removed was measured at the distal root of the second molar tooth (11.26mm), and at least the first premolar tooth (5.52mm) was measured for buccal resection. The distal root of the second molar tooth was found to be the closest tooth root to the MC with a mean of 2.75mm, and the closest distance was measured as 0mm. It is important to evaluate the parameters such as mandibular buccal and lingual bone thickness, location of the MC and the MF, and root size for atraumatic endodontic surgical approach. Evaluation of these data before endodontic surgery provides guidance to the clinician in the planning of endodontic surgery. The mandibular posterior region, which is difficult to reach with traditional surgical approach, is now easily reached using an operation microscope. For this reason, endodontic surgical procedures have become popular in mandibular posterior teeth. Therefore, the relationship between the mandibular posterior teeth and anatomical structures that are important in the planning of surgical access line is examined in this study.

Exposure level control of power frequency electric field near angle tower of 500kV transmission lines

The distortion of power frequency electric field in the roof space near the angle tower of EHV line is serious, which is an important factor to be considered in transmission line planning and design. This paper establishes a three-dimensional electric field simulation model near the angle tower of 500 kV transmission line and verifies the validity of the simulation by field measurement. Based on this, the factors affecting the spatial electric field level on the roof of the house near the angle tower are analysed. Finally the control distance of the house near the angle tower is calculated according to the electric field exposure limitation in Chinese standards. The results show that the electric field near the transmission line is distorted and elevated by the house, and the electric field level of the roof decreases with the increase of the distance between the house and the line, and decreases with the decrease of the height of the house and the angle of the line.

Large-scale ecological red line planning in urban agglomerations using a semi-automatic intelligent zoning method

Ecological red line (ERL) planning is an effective measure for ecological protection and management. Although many attempts have been made in this field, most have targeted a single city. The task of ERL planning will become particularly difficult in large regions, given the complexity of city networks. Another concern is that ERL schemes cannot be easily coordinated with pre-existing land-use plans and may even conflict with one another, since every plan has its own boundaries, management policies, and other constraints. To address these problems, this study presents a novel framework for large-scale ERL planning whose contributions are twofold. First, we developed a top-down planning strategy that could ensure both the consistency of ecological management and equality for every city within large regions. Second, we propose a semi-automatic intelligent zoning method based on a modified genetic algorithm. The difference between “semi-automatic” and “automatic” is that the former allows users to manually identify some key protected areas. This integrated framework was applied to ERL planning in an urban agglomeration. Three groups of evaluations indicated that the planning schemes generated via the proposed framework are more practical and closer to reality than the results of traditional methods. For example, the comparison between semi-automatic and automatic methods suggested that the former can generate zoning schemes that are easily coordinated with previous land-use plans. Therefore, this comprehensive framework could facilitate large-scale ecological management and planning and will be helpful for the design of environmentally sustainable cities.

Automated design of multi-station assembly lines

Automated assembly lines are a fundamental part of today’s manufacturing industry. Due to shortening product life cycles and an increasing number of product variants, assembly lines have to be designed with increasing frequency. Currently, all design decisions are based on the knowledge and expertise of engineers and the design process results in a high amount of manual effort. This paper therefore presents an approach to making the knowledge of these experts explicit and using it as the basis for the automated planning of multi-station assembly lines. The proposed planning method includes the scheduling of the assembly line and the selection of resources and their positioning into a feasible layout.

Multi-Level Planning and Scheduling for Parallel PCB Assembly Lines Using Hybrid Spider Monkey Optimization Approach

Printed circuit board (PCB) assembly lines are significant to produce a variety of electronic products. PCB manufacturing industries tend to move towards automated and complex manufacturing system due to an increase in the customer demand for more sophisticated products. PCB assembly process involves highly interrelated levels of planning and scheduling problems. Therefore, the current research investigates multi-level planning and scheduling of PCB assembly lines, which include line assignment to the PCB models, component allocations to machines, and component placement sequencing by machines on PCB boards. A mixed integer-programming model is developed to integrate the planning and scheduling problem of parallel PCB assembly lines to maximize the net profit. A hybrid spider monkey optimization (HSMO) algorithm is proposed to solve the multi-level planning and scheduling problem. The performance of the proposed HSMO algorithm is compared to artificial bee colonial (ABC), genetic algorithm (GA), particle swarm optimization (PSO), and simulated annealing (SA) algorithms. Moreover, the proposed HSMO algorithm is validated against ABC, GA, PSO, and SA algorithms with the case problem taken from well-reputed PCB manufacturing industry in China. The computation experiments indicate that the proposed HSMO algorithm can achieve good near-optimal solutions when compared with the other-mentioned four algorithms based on performance and efficiency for benchmark problems and real case problem.

Automatic layout generation of robotic production cells in a 3D manufacturing simulation environment

Facing an increasing demand for flexible and reconfigurable production lines, the development and implementation of extensive simulation tools for faster planning of robot cells or entire production lines continue to gain importance. Simulation tools offer the opportunity to test robotic applications before the physical existence of the system, to ensure reachability and feasibility of the actual cell implementation and examine compliance with the desired cycle time during process execution. During simulation analysis, extracting data from the given layout and building the corresponding simulation model takes a considerable amount of time. To reduce the required time, one applicable approach is to automate the generation of the simulation model using data from tools used prior to the simulation analysis, such as layout planning tools. So far, data representation limits the straightforward data exchange between planning and simulation tools and constitutes a time-consuming task during simulative ramp up. This paper focuses on the automatic layout generation in a 3D simulation environment. To enable automatic layout generation, a suitable representation of the imported layout data is derived. For this purpose, available data exchange formats are compared and their suitability for automatic model generation is evaluated. As a result of the evaluation, AutomationML is identified to meet the requirements best. Using this format, the development of an interface is described, which makes it possible to import layout data into the simulation environment of Visual Components and automatically generate a simulation-model of the complete robotic cell layout.

Aggregation techniques for frequency assignment in public transportation

In public transportation, frequency assignment is a sub-problem of line planning which is responsible for assigning each route of a line a certain frequency with which they are serviced by vehicles. Frequency assignment is among the most important decision problems for optimizing the waiting times in a transportation network and is often a very complex matter. This paper focuses on different aggregation techniques for reducing the computational effort to obtain (near-)optimal line frequencies. In detail, the influence of different model formulations and strategies for customer input data aggregation are investigated. For this purpose, six models are provided, their computational complexity is investigated and suitable mixed-integer mathematical programs are developed. These models vary in the levels of line utilization detail and predict the resulting travel times. Both aggregation techniques are evaluated according to their influence on the solution quality, which is determined by the transport suppliers’ point of view as forecast accuracy of the weighted number of customers using the transport. This comprehensive computational study reveals that some model formulations reduce the computational effort considerably by only small losses in line frequency quality. Furthermore, dramatically compressed customer data lead to (near-)optimal line frequencies.

Analysis on Passenger Flow Changes during Holidays—A Case Study of Beijing-Shanghai High-Speed Railway

In China, the number of passengers taking the high-speed train will increase dramatically during the short-term holidays. However, only a few researchers have analysed the characteristics of high-speed railway passenger flow change during the holidays and all of them just focused on the total number change, lacking analysis on different OD types. Therefore, in order to provide specific advice for making and optimizing the holiday high-speed train line plan, this paper studied passenger flow change during holidays based on OD classification, taking Beijing-Shanghai High-Speed Railway (BSHR) as an example. Firstly, we classified OD pairs into different groups according to OD level and OD distance, while the OD level is defined by the station level which was obtained by Hierarchical Clustering Method. Secondly, by counting and calculating the increased number of passengers during each holiday for each OD group, we drew the conclusion that the increased passenger flow of BSHR in holidays is mainly from the 2nd level OD, 1st level OD and [0, 500)km OD. Due to this result, we suggest to increase the service frequency of 1st and 2nd level OD pairs in holidays. Also, we prefer to add short-distance trains and try to avoid adding too many long-distance trains.

The line planning routing game

In this paper, we take a novel perspective on line planning in public transportation: We interpret line planning as a game where the passengers are players who aim at minimizing individual objective functions composed of travel time, transfer penalties, and a share of the overall cost of the solution. We discuss the relation among equilibria of this game and line planning solutions found by optimization approaches. Furthermore, we investigate the algorithmic viability of our approach as a solution method for line planning problems, using a best-response algorithm to find equilibria. We investigate under which conditions a passenger’s best-response can be calculated efficiently and which properties are needed to guarantee convergence of the best-response algorithm.

Determining and Evaluating Alternative Line Plans in Out-of-Control Situations

From time to time, large disruptions cause heavily utilized railway networks to get into a state of out-of-control, in which hardly any trains are able to run as the result of a lack of accurate and up-to-date information available to dispatchers. In this paper, we develop and test disruption management strategies for dealing with these situations. First, we propose an algorithm that finds an alternative line plan that can be operated in the affected part of the railway network. As the line plan should be feasible with respect to infrastructural and resource restrictions, we integrate these aspects in the algorithm in a Benders-like fashion. Second, to operate the railway system within the disrupted region, we propose several local train dispatching strategies requiring varying degrees of flexibility and coordination. Computational experiments based on disruptions in the Dutch railway network indicate that the algorithm performs well, finding workable and passenger-oriented line plans within a couple of minutes. Moreover, we also demonstrate in a simulation study that the produced line plans can be operated smoothly without depending on central coordination.