Line Route Research Articles

Assumptions for the mathematical model investigating the effect of railway line route parameters on the average speed of railway vehicles

Rail transport is the most efficient alternative to road transport. The popularity of this branch is constantly growing. As a consequence, it is noticed that key terminals, railway routes and HUB stations are constantly being overloaded, resulting in a reduction in the available capacity. This necessitates the passage of higher priority trains (mainly passenger trains), which requires the introduction of additional stops for freight trains and consequently reduces commercial speeds. A railway line is characterized, m.in, by parameters such as: electrification, maximum speed, railway line class, track width, etc. Each of these parameters can have an impact on the average speed of rail vehicles in rail transport. An additional factor determining speed is the capacity of railway lines. Due to the lower capacity and the consequent low average commercial speed, alternative routes for trains are being sought. The aim of the article is to analyze the assumptions for the mathematical model of the influence of technical parameters of routes and capacity of railway lines on the average speed of rail vehicles. In order to achieve this goal, the article is divided into five sections. The first section is an introduction to the article. The second section describes theoretical issues related to modelling in transport. The third section describes the issues of mathematical modeling using graph theory. The practical application of graph theory on the selected example is described in the fourth section. A summary of the article and preliminary research is presented in the last section.

The influence of a Tunnel Boring Machine on a building in Sofia City Center, located above the route of the third Metro line

The construction of the third line of Sofia underground railway (Sofia Metro) used to be one of the major priorities of the geotechnical engineers in the Bulgarian capital for a period of at least two years. Since the first and second lines pass under the existing streets and parks, the third line is designed to go under some buildings erected in the last century. These buildings have been part of the architectural cityscape for years. Such is the case described in the present paper. The underground railway is designed to pass under a building in the Sofia city center. It is a five-story skeletal building, constructed on single and strap foundations. The purpose of the study is to establish whether the settlement due to the passing of the Tunnel Boring Machine (TBM) will adversely affect the structure of the building. The solution is for a single plane task. Data given in the manual of the TBM and the subsoil geotechnical properties are used in order to define the behavior of the soil massif. After the calculations have been made, the relative settlement of the building is determined to be much smaller (1/1662) than the allowable one (1/500). Then the maximum relative settlement is calculated to be 1/1054, which is higher than the average settlement for the whole building, but much less than the allowable. The calculations and comparisons are confirmed in practice.

A COMPARATIVE STUDY OF HEADWAY-BASED AND TRANSPORT SYSTEM-BASED ASSIGNMENTS OF PUBLIC TRANSPORT IN VISUM: THE CITY OF KRYVYI RIH CASE

Many researchers have explored public transport assignment methodologies employing transport modelling software. Nevertheless, there remains a gap in evaluating real-world public transit networks utilizing diverse assignment procedures within Visum software. This paper introduces a thorough comparison of algorithms involved in public transport assignment processes, using the transport model of the city of Kryvyi Rih in Ukraine. The three scenarios of the model were developed depending on the public transport assignment procedure: headway-based, transport system-based utilized to all links, turns, and major turns in the network graph, and transport system-based applied only to the links, turns, and major turns traversed by the active public transport lines. The model of the network comprises 13 transport systems, 7 transport modes, 27598 links, 10097 nodes, 83270 turns, 238 zones, 1748 connections for private transport, 3013 connections for public transport, 534 stops, 1165 stop areas, 1190 stop points, 130 lines and 218 line routes. The transport demand model encompassed 14 demand segments. Compared to the outputs of the model calculation using the headway-based procedure, in the scenarios with transport system-based assignment, passenger flows on rail tram lines significantly decreased. Also, the results of scenarios with transport system-based assignment showed that the passengers extremely use parallel streets for travel from an origin to a destination. The modelling outputs for an actual urban network illustrate that the choice of the shortest route in the transport system-based assignment is closely linked to the main urban roads. This circumstance could potentially result in a rise in the number of transfers needed to sustain accessibility to districts residing far from the central highway.

A Comparation Study of Transmission Line Routing Based on A* and RRT Algorithms

Transmission line design is an important part of power grid engineering design, and transmission line path selection is the basis of line design. Transmission line route selection is to select a line path that can not only meet the requirements of power transmission and consumption, but also consider the cost control of the line, and avoid the farmland, highways, ecological exclusion zone between the start and end of the transmission line. The path scheme is constrained by geographical factors, project cost, construction conditions, operation and maintenance conditions, which makes the path selection show the characteristics of comprehensive diversity, spatial complexity, policy influence and so on. In the traditional route selection of transmission lines, line design specialists need to go through blind route selection, site survey and other steps to determine the path scheme, but because of insufficient effectiveness of the map, it is difficult to reflect the real environmental information, resulting in repeated route selection work to determine the final path scheme. In this paper, the selection principle of transmission line path is introduced first. Then, two path optimization algorithms, i.e. A* algorithm and rapidly expanding random tree (RRT) algorithm, are used to select transmission lines respectively. Finally, the advantages and disadvantages of these two algorithms in practical engineering line selection design are comparatively analyzed. Compared with the way of A* algorithm, RRT algorithm is more suitable for practical application of power system. It aims to provide a reference for the method of intelligent line selection in subsequent transmission design.

ROBUST OPTIMIZATION MODEL OF CONTAINER LINER ROUTES IN FEEDER LINE NETWORK

The universal application of the hub-and-spoke maritime network makes feeder line network key to restricting the quality and efficiency of maritime transportation. However, container liner routes in feeder line network are susceptible to the changes in shipment demand and international fuel prices. Therefore, based on the hub-and-spoke maritime network, this paper constructs a robust optimization model of container liner routes in feeder line network. Under the capacity and time constraints, routes optimization and ship equipment under uncertain environment are analysed. An improved tabu search algorithm was designed based on the characteristics of the model. The example analysis proves that the model can still ensure the robustness of routes under uncertain environment, which is more applicable than the deterministic model.

Corrosion failure of stainless-steel in caustic soda lines

Abstract The paper deals with the case studies of stainless steel piping corrosion in caustic soda transfer lines at a hydrocarbon processing plant, in the Asian region. The lines were in service of transferring the caustic soda solution from the storage tank farm to different process units, for subsequent use in reaction vessels. To maintain a minimum temperature of the fluid to avoid its precipitation, the lines were accompanied by a steam heat-tracer, throughout the line route. The material of construction (MOC) of the line was stainless steel type 316. After a period of about 3.5 years, 2” caustic line suffered fluid leakage, which was noticed through significant salt accumulation over insulation at one location. A valve was also noticed to leak through a weld at a 1.5” distribution line. The affected components were removed from service and subjected to detailed inspection and laboratory investigation, using advanced tools of metallurgical analysis and characterization. It was found that leakage in 2” line had occurred due to poor workmanship used during the repair of a manufacturing defect at the affected location and leakage of the valve had taken place due to the use of improper welding practice (in the case of subjected weld). In addition, the significant role of metallurgical defects in the parent metal was also disclosed to result in the observed failures. In addition, the contribution of process excursions can’t be completely ruled out. Finally, remedial measures are given to avoid the recurrence of such failure.

Carbon and cost accounting for liner shipping under the European Union Emission Trading System

Excessive CO2 emissions and increased total costs of liner shipping are the two main problems affecting the environmental and economic benefits of liner companies under the European Union Emission Trading System (EU ETS). To address the upcoming EU ETS, we propose a carbon and cost accounting model for liner shipping that accurately calculates CO2 emissions and total cost of liner shipping. We conduct a case study that a containership operates on the liner route from the Far East to Northwest Europe. The results show that the sailing stage plays a pivotal role in CO2 emissions from liner shipping, accounting for 94.70% of CO2 emissions. Among four types of fuel, CO2 emissions from liner shipping using MGO is the largest, while CO2 emissions from liner shipping using methanol is the smallest. Methanol, as an alternative fuel, proves to be a better choice than LNG for CO2 control of liner shipping. The relationship between sailing speed and CO2 emissions follows a U-shaped curve for the selected containership. Notably, speed reduction is effective in carbon control of liner shipping only when the sailing speed exceeds 8.29 knots. Under the EU ETS, sailing speed is a key variable affecting the total cost of liner shipping. Speed reduction may not always be cost-effective. When keeping the total cost of liner shipping unchanged, sailing speed should be reduced as the EU allowance (EUA) price rises within a certain range. For the selected containership using MGO and HFO, the most economical sailing speed is 8.29 knots, corresponding to the increase in EUA price of 304.95% and 261.21%, respectively. If EUA price continues to rise, speed reduction will become ineffective in controlling the total cost of liner shipping. This model can enhance the environmental and economic benefits of liner companies, meet compliance requirements of the EU ETS, and provide a new perspective for carbon and cost control of liner shipping.

A Bus Network Design Model under Demand Variation: A Case Study of the Management of Rome’s Bus Network

This paper proposed a methodology to design bus transit networks that can be consistently adjusted according to demand variations both in level and distribution. The methodology aims to support the activities of service providers in optimizing the service capacity of the bus network according to a system-wide analysis. It stems from the changes imposed by the COVID-19 pandemic. Such an experience has imposed a rethinking of the methodology used for the optimal design of robust transit network services that are easy-to-adapt to demand variations without redesigning the whole network every time. Starting from an existing model, this design methodology is articulated in two parts: the first part for solving the problem with the maximum level of transit demand, aiming at giving an upper bound to the solution, and the second part, where the network is optimized for other specific transit demands. This method has been applied to a real context in the city of Rome, considering two levels of demand taken from COVID-19 experiences. They are characterized by the application of different policies regarding different timings for shopping and schools’ openings as well as by policies on smart working. The results show the effectiveness of the proposed methodology to design robust transit networks suited to comply with large demand variations. Moreover, the procedure is suitable and easy to implement, in order to adapt quickly to changes in demand without having to modify line routes, but adapting them in an optimal way, even when dealing with realistic-sized transit networks.

The Influence of Service Quality and Price on KRL Commuter Line Route Solo – Jogja to Customer Loyalty

Transportation as an important element in human life, plays a role in facilitating daily activities and supporting the economy. But because of the heavy traffic caused by so many motorized vehicles, people are looking for alternate options, including taking the KRL commuter line. This study attempts to determine how customer loyalty is affected by the cost and level of service provided on the KRL Commuter Line Solo-Jogja route. The findings, which emphasize providing excellent service and living up to customer expectations, demonstrate that service quality has a favorable and substantial impact on customer loyalty. However, pricing has little effect on consumer loyalty. This is mostly because workers use the KRL Commuter Line a lot when they are commuting, which may make prices inaccessible to some groups. Customer loyalty is influenced by both price and service quality, according to simultaneous study, which implies that raising prices and enhancing customer service quality can boost customer loyalty. However, this study adds to our understanding of the variables influencing consumer loyalty in the context of public transportation in particular and is significant in relation to the Solo-Jogja route of the KRL Commuter Line.

Gelsari and Lentini marshes (Sicily, Italy), a wetland of extremely high biodiversity. Consequences on avifauna from the crossing of an overhead high-voltage power line

In the Gelsari and Lentini marshes (Sicily, Italy), which constitute a vast and historically well-known wetland on the central eastern coast of Sicily, the crossing of an overhead high-voltage power line surprisingly had been planned and approved. This choice was made despite the high landscape value that these marshes possess, the environmental protection constraints they enjoy, the interest they hold for the biodiversity conservation in Sicily, and their extraordinary ability to attract avifauna. At present, the work, which began in August 2021, has resulted in the placement of all supports. An estimate of the risk of mortality of avifauna that the presence of the power line will produce has been made, limiting the survey to species of high conservation interest, which are among those present in the marshes. It turned out that the risks of collision of avifauna and especially of species considered of high conservation interest, due largely to the characteristics of the power line and especially its route, are extremely high; the damage that is likely to occur does not, therefore, seem to have been properly assessed, neither at the design nor at the approval stages of the project. Given that the impact of the power line does not appear to be mitigable, neither with regard to the landscape nor with regard to avifauna, considering, in the latter case, especially the high mortality risks to which species of high conservation interest would be subjected, it is believed that the only solution to avoid such damage is to make a modification to the route of the power line in the section affecting the marshes.

The Importance of Rail Transport for Transport Services in Peripheral Areas

Abstract This article focuses on the evaluation of the importance of passenger rail transport for transport services in peripheral areas. The term peripheral area is defined, and the different types of peripheral areas and their characteristics are listed. Based on the analysis of these areas in the Czech Republic, the authors generally divide passenger rail transport services in peripheral areas into three categories according to the route of the railway line within the peripheral areas and towards the centre. The authors set out the most important criteria to assess the importance of individual line categories for transport services in peripheral areas. Based on the SWOT analysis and using the TOWS matrix, specific strategies and proposals are presented to address passenger rail services in the peripheral area. The aim of this article is to evaluate the importance of rail transport in peripheral areas using the criteria selected by the authors.

Анализ молниевой активности в Мурманской области в 2022 г.

The article analyses lightning activity in 2022 on the Murmansk region territory according to the data of the non-commercial lightning detection network — Blitzortung. Data on the duration of the thunderstorm season, the number of thunderstorm days, the number of lightning discharges and their distribution over the territory are given. The statistics of emergency failures of overhead power lines caused by lightning strikes in the power grids of the Kola power system are investigated. An example of an analysis of the intensity of lightning activity along the overhead line route is presented.

Bended Differential Line Routing Adaptive Designed by Periodic Nonuniform Structure With Ultrawideband Mode Conversion Noise Suppression

Bended Differential Line Routing Adaptive Designed by Periodic Nonuniform Structure With Ultrawideband Mode Conversion Noise Suppression

Typification of Projects for Development of High-Speed Rail

The emerging demand for improving consumer parameters of rail passenger transport leads to the need to build a dedicated railway infrastructure for passenger trains with speeds exceeding in some sections 250 km/h. The high capital intensity of dedicated infrastructure development projects imposes significant restrictions on their scope and financial feasibility. The geographically determined location of urban agglomerations in European and Asian countries has led to formation of many approaches to the routing of lines for high-speed passenger transportation.The projects for development of dedicated high-speed railways being developed in various countries differ in their technical, technological, and operational characteristics. The use of different approaches has led to different efficiency of the passenger traffic, expressed in the demand of passengers for transportation.A structural analysis of existing high-speed transportation projects allowed revealing general patterns of their development. By the number of operational tasks arising with regard to movement of trains, the phases of traffic development were divided into linear, tree­like and network stages. Thus, when moving from the linear structure of a high-speed rail, an additional problem arises of trains passing from the main track to the secondary one. The transition to the network stage can result in emergence of parallel passages rail tracks between urban agglomerations.To generalise the experience of operating high-speed systems in the world, the article describes the developed method that allows comparing different projects for organising high-speed rail with each other. The comparison is made according to the main characteristics of traffic: travel time between separation points, the traffic speed, the total length of the railway line. Identification of the patterns inherent in various projects for development of high-speed rail will make it possible to compare their technological parameters, to identify the scope of rational use of high-speed lines and areas of competition with other core types of transport.

Dynamic pricing and competition of container liner shipping services in a duopoly spot market

With the application of online booking technology in the spot market of container liner shipping, dynamic pricing is considered an important tool and development trend to balance container shipping supply and demand from the spot market. This study examines the dynamic pricing and competition of container liner shipping services in a duopoly spot market where two shipping companies compete on liner routes with multiple overlapping origin–destination (O-D) pairs. The demand within the spot market for one shipping company is sensitive to both the freight rate set by the shipping company and its competitor. To tackle this complex challange, a non-linear mixed-integer generalized Nash equilibrium optimization model was formulated for the dynamic pricing and competition problem to maximize the profits of both shipping companies. To effectively reach the optimal solution for the dynamic pricing and competition problem, the proposed model is reformulated as a linear complementary problem with a Karush-Kuhn-Tucker (KKT) conditional system. An optimal response decomposition algorithm is developed to obtain the global optimal solution of the model. Numerical experiments with the Trans-Pacifc shipping network of two oligarchic shipping companies were conducted to demonstrate the efficiency of the solution algorithm and the applicability of the proposed model in improving the two companies’ profits from the spot market.

ANALYSIS OF THE CAUSES OF DEGRADATION PRESTRESSED REINFORCED CONCRETE RAILWAY SLEEPERS

Railway sleepers are a very important component of the transport infrastructure, they are dynamically loaded and subject to many stresses that can cause degradation, shorten their service life and also reduce the safety of rail transport. The subject of the study was damaged-highly cracked prestressed concrete railway sleepers, 10 years old, sampled on the railway line route. The results of the investigations carried out to determine the characteristics of the concrete are presented. In order to determine the cause of the damage, low-frequency fatigue tests were also carried out in the laboratory to measure vibrations and to check for cracks. By checking the microstructure of the concrete with SEM-SEI and EDS electron microscopy, we found that the cracks were caused by chemical reactions in the hydrated concrete. The results of the analyses carried out can improve the criteria for the inspection and assessment of the serviceability of degraded railway sleepers during their service life.

Assessment of AC Corrosion Probability in Buried Pipelines with a FEM-Assisted Stochastic Approach

In this paper, a stochastic approach is combined with field theory and circuit methods to study how the geometrical and electrical properties of holidays (defects or pores in the insulating coating) in a metallic pipeline influence the probability of exceeding the current density limit for corrosion. Three-dimensional FEM simulations are conducted to assess the influence of the shape and electrical resistivity of the pore on the computed spread resistance value. The obtained results are then used to evaluate the probability of exceeding a given current density value for different sizes of pore and soil resistivities. Finally, a case of 50 Hz interference along a pipeline-transmission line routing is examined. The probabilistic approach presented in this paper allows the pipeline sections more subjected to the induced AC corrosion risk to be identified to be used as an auxiliary tool for adopting preventive protection countermeasures. Lastly, unlike most papers devoted to assessing electromagnetic interference on pipelines, the present work uses a probabilistic rather than a deterministic approach, representing its main novelty aspect.

TRANSMISSION SUITABILITY ROUTE MAP USING THE LEAST COST PATH ANALYSIS (LCPA)

This study uses a Least Cost Path Analysis (LCPA) to create a transmission suitability route map. Environmental issues including electromagnetic pollution, habitat fragmentation, forest clearing, and the sight of pylons and power lines, and electromagnetic pollution are just a few that may come up during the planning and construction phases. The study's objectives are to define the criteria for a suitable transmission route, map the current transmission from Kidurong to Kemena in Bintulu, Sarawak, and suggest a new, LCPA-based transmission route that meets these criteria. It is necessary to determine the criteria that influence the construction of the route. There are three main categories for the proposed routes. There are technical, human health, and natural environments. The road layer and slope layer are combined for the technical group. The residential layer is part of the human health group, and land use is associated with the natural environment. During the planning of a potential power line route, weight was assigned to the criterion maps. The outcome demonstrates that the suggested route was built based on most flat sections, with only a little portion passing through the sharpest sector because there is no other way to depart from the path to avoid it. The output route is nearly straight from the source location to the destination point. The route also curves in a couple of places to go around the step area. The proposed transmission line is inside the buffer zone, and there are no other routes in the area that are more than 1 km from the road. Class 1 has a low dwelling density; therefore, the route passes through it for the residential evaluation. Additionally, there are a few places where the route passes through class 2 because only class 2 has a lower housing density.

Reduction of tram noise by using a rail lubrication device

Tram noise is a source of environmental pollution, especially in urbanized areas. The main source of such noise comes from the interaction between wheels and rails. For this reason, the route of the tram line can run along tight bends, and the particular lines end up in loop-shaped tram depots. Such geometric solutions cause a characteristic squeak and a significant increase in noise level in comparison to trams passing along a straight part of tramway. The article undertakes the task of assessing the impact of a lubrication device mounted in the tramway on the reduction of environmental noise. The article concerns the tests of a track surface made of wooden sleepers and rails. The obtained results indicate that the reduction of sound level due to the use of a lubrication device reaches up to 26.6 dB (A) for the loudest tram carriages.

Оценка видового разнообразия растительности, произрастающей на территориях линейных инфраструктурных объектов Центральной России

When form protective forest stands along linear infrastructure facilities, the problem of subsequent spontaneous reproduction of trees and shrubs arises, littering the territories of the above facilities and creating a threat to the safety of their operation. Works on cleaning the territories of infrastructure facilities from unwanted tree and shrub vegetation are often organized without a sufficiently clear idea of the characteristics of the said vegetation to be removed, which negatively affects the quality of the performance of these works.The purpose of the research is to determine the species composition of undesirable plant communities that form on the territories of linear infrastructure facilities in order to increase the efficiency of their removal and draw up recommendations for the proper maintenance of these territories. It was revealed that most types of undesirable vegetation growing on the territories of linear infrastructure facilities in the Central part of Russia belong to Magnoliophyta (flowering, about 97 %) and Pinophyta (gymnosperms, about 3 %).It was revealed that most types of undesirable vegetation growing on the territories of linear infrastructure facilities in the Central part of Russia belong to Magnoliophyta (flowering, about 97 %) and Pinophyta (gymnosperms, about 3 %). About 54 % of the protection zones of power lines and right of way of roads, as well as about 33 % of the right of way of railways in the Central part of Russia have a similar species composition of unwanted vegetation, however, the maximum similarity is not ensured by the location of sections of infrastructure facilities in close proximity to each other. For the protection zones of power lines, it is possible to determine the species composition of growing undesirable vegetation in one of these areas, followed by dissemination of the results of the study to another nearby area. For railroad right of way, such dissemination of the study results is inappropriate. In fact, on each of the sections of the right of way of roads and railways, as well as the routes of power transmission lines in Central Russia, such types of unwanted vegetation grow as ash-leaved maple (Acer negundo L., with a share of participation in the studied plant communities from 6.3 % to 98.1 %) and smooth elm (Ulmus laevis Pall, with a share of 1.1 % to 41.1 %). Among the types of unwanted trees and shrubs most expected to grow in these territories, about 36 % are prone to their renewal by stump growth, about 42 % – by root offspring, about 22 % – by other means. To increase the efficiency of removing unwanted vegetation in order to properly maintain the territories of infrastructure facilities, it is recommended to apply methods and methods that provide for either mechanical removal of the specified vegetation along with its roots (for example, its uprooting), or a combined effect on it: removal of above-ground parts of vegetation in the fall with a mandatory subsequent spring herbicide treatment of emerging young stumps and root offspring.