Pub Date : 2023-09-26DOI: 10.3846/transport.2023.18334
Izabela Kalbarczyk, Anna Kwasiborska, Sylwester Gładyś
Airlines strive to minimize the waiting time for passenger service at the airport. Modification of the passenger service process at check-in stands can be carried out by modelling and then simulating various scenarios in order to obtain time benefits. The organization of service for departing passengers is the most complex system, which includes numerous maintenance activities aimed at preparing them and their luggage for transport by aircraft. Therefore, this article aims to present a few scenarios to improve the passenger service process. Based on the research, assumptions were made for each check-in scenario. Then, the models were implemented in the SIMIO simulation program. In the next step, the passenger distribution for individual desks was modified and a comparison was made with the level of passenger service defined by International Air Transport Association (IATA). The simulation results for individual scenarios are presented and the benefits to be achieved after introducing the proposed changes are indicated. The simulations carried out showed 2 important elements in the current and proposed layout of the ticket and luggage service stations and the introduction of changes to the baggage desks. Article presents the specification of the time spent in the system and waiting in the queue. The conducted analyses have shown that the proposed concept will allow for taking over 40% of passengers using the adjacent Fast Bag Drop (FBD) stands. Research has shown that adding more machines for use will fully cover the demand for FBD. The conclusions presented in the article are valuable when introducing modernization of the passenger and baggage handling process. For future researches, it would be beneficial to test other simulation tools and other scenarios to compare these results with those presented in this article.
{"title":"THE DECISION SUPPORT FACILITATING THE CHECK-IN SERVICE AT THE CHOPIN AIRPORT WITH THE USE OF COMPUTATIONAL EXPERIMENTS IN SIMIO","authors":"Izabela Kalbarczyk, Anna Kwasiborska, Sylwester Gładyś","doi":"10.3846/transport.2023.18334","DOIUrl":"https://doi.org/10.3846/transport.2023.18334","url":null,"abstract":"Airlines strive to minimize the waiting time for passenger service at the airport. Modification of the passenger service process at check-in stands can be carried out by modelling and then simulating various scenarios in order to obtain time benefits. The organization of service for departing passengers is the most complex system, which includes numerous maintenance activities aimed at preparing them and their luggage for transport by aircraft. Therefore, this article aims to present a few scenarios to improve the passenger service process. Based on the research, assumptions were made for each check-in scenario. Then, the models were implemented in the SIMIO simulation program. In the next step, the passenger distribution for individual desks was modified and a comparison was made with the level of passenger service defined by International Air Transport Association (IATA). The simulation results for individual scenarios are presented and the benefits to be achieved after introducing the proposed changes are indicated. The simulations carried out showed 2 important elements in the current and proposed layout of the ticket and luggage service stations and the introduction of changes to the baggage desks. Article presents the specification of the time spent in the system and waiting in the queue. The conducted analyses have shown that the proposed concept will allow for taking over 40% of passengers using the adjacent Fast Bag Drop (FBD) stands. Research has shown that adding more machines for use will fully cover the demand for FBD. The conclusions presented in the article are valuable when introducing modernization of the passenger and baggage handling process. For future researches, it would be beneficial to test other simulation tools and other scenarios to compare these results with those presented in this article.","PeriodicalId":23260,"journal":{"name":"Transport","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135719313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-04DOI: 10.3846/transport.2023.18291
Celestino Sánchez Martín, David Calonge Cases, M. Milenković
Despite the increasing relevance of Open Science (OS) in the European research landscape, very few publications have addressed the analysis of its role within the European rail context. To this effect, the present paper aims at contributing to shed light on the topic by setting the cornerstone for a differentiated analysis of OS in this sector. In order to do so, the analysis is divided into 2 main sections. The 1st provides an overview of initiatives and experiences regarding OS, which have been recently carried out in the sector. The analysis of initiatives and scientific publications has shown that Open Data (OD) is the area attracting more attention and with more potential for expansion mainly due to the commercial interest of the data. As expected, the use of Open Tools (OT) is common but, interestingly, a growing interest in the development of OT in the sector has been detected. The creation of Open Standards (OSt), developed by specific rail stakeholders’ groups or by coalitions of different stakeholders is increasing in the last years. Amongst the OS areas analysed, Open Access (OA) and Citizen Science (CS) have shown less progress. However, tendencies toward an increasing interest in these areas within the sector has been also detected. The 2nd section aims to uncover the issues or barriers preventing a wider spread of OS specifically in the rail sector and suggest regulatory avenues and actions to overcome them. The identified issues revolve around 3 topics: the lack of initiative on behalf of the European Union (EU) to a) engage other stakeholders beyond the field of research, and b) leverage untapped OS potential in sector-specific situations, which could contribute to its development; and finally, the absence of a sector-specific OS framework. The establishment of such a framework could have a significant positive impact in OD, which is the most appealing area and thus contributing to the uptake of OS as a whole in the sector. In view of such issues, the present paper suggests the establishment of: (1) a European Rail Open Science Policy Platform in order to create a forum-like space in which to align the stakeholder’s positions, and (2) a Joint Rail Data Action Plan to design an OS governance framework, with the aim to ensure the usability, quality, and reliability of data. After identifying the state of OS in the rail sector and the uncovering of several issues that are hindering its development, this paper concludes that the constant further monitoring with regards to needs, challenges and interests (or lack of such) of the different rail stakeholders is key to ensure the continuous development of OS.
{"title":"AN OVERVIEW ON OPEN SCIENCE IN THE EUROPEAN RAIL SECTOR","authors":"Celestino Sánchez Martín, David Calonge Cases, M. Milenković","doi":"10.3846/transport.2023.18291","DOIUrl":"https://doi.org/10.3846/transport.2023.18291","url":null,"abstract":"Despite the increasing relevance of Open Science (OS) in the European research landscape, very few publications have addressed the analysis of its role within the European rail context. To this effect, the present paper aims at contributing to shed light on the topic by setting the cornerstone for a differentiated analysis of OS in this sector. In order to do so, the analysis is divided into 2 main sections. The 1st provides an overview of initiatives and experiences regarding OS, which have been recently carried out in the sector. The analysis of initiatives and scientific publications has shown that Open Data (OD) is the area attracting more attention and with more potential for expansion mainly due to the commercial interest of the data. As expected, the use of Open Tools (OT) is common but, interestingly, a growing interest in the development of OT in the sector has been detected. The creation of Open Standards (OSt), developed by specific rail stakeholders’ groups or by coalitions of different stakeholders is increasing in the last years. Amongst the OS areas analysed, Open Access (OA) and Citizen Science (CS) have shown less progress. However, tendencies toward an increasing interest in these areas within the sector has been also detected. The 2nd section aims to uncover the issues or barriers preventing a wider spread of OS specifically in the rail sector and suggest regulatory avenues and actions to overcome them. The identified issues revolve around 3 topics: the lack of initiative on behalf of the European Union (EU) to a) engage other stakeholders beyond the field of research, and b) leverage untapped OS potential in sector-specific situations, which could contribute to its development; and finally, the absence of a sector-specific OS framework. The establishment of such a framework could have a significant positive impact in OD, which is the most appealing area and thus contributing to the uptake of OS as a whole in the sector. In view of such issues, the present paper suggests the establishment of: (1) a European Rail Open Science Policy Platform in order to create a forum-like space in which to align the stakeholder’s positions, and (2) a Joint Rail Data Action Plan to design an OS governance framework, with the aim to ensure the usability, quality, and reliability of data. After identifying the state of OS in the rail sector and the uncovering of several issues that are hindering its development, this paper concludes that the constant further monitoring with regards to needs, challenges and interests (or lack of such) of the different rail stakeholders is key to ensure the continuous development of OS.","PeriodicalId":23260,"journal":{"name":"Transport","volume":"18 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87445672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-20DOI: 10.3846/transport.2023.19084
J. Brezinová, J. Hašuľ
The article is the result of research evaluating the quality of fillet welds used in the production of rear seat backrests for passenger cars and manufactured robotically by Cold Metal Transfer (CMT) robotic Metal Active Gas (MAG) welding. When robotizing the process, parameters such as the speed of the process itself, accuracy and quality of the welded joints are important. Dual-phase ferritic-martensitic steel HCX 590X was used for the experiment and four weld nodes were evaluated. The quality of welded joints was evaluated by visual and capillary methods. Based on the metallographic analysis, the weld depth of the weld root was evaluated. The measured values were subsequently processed by statistical method ANalysis Of Variance (ANOVA). The research confirmed that the final quality of the welds depends on the depth of the weld root weld into the Base Material (BM). This parameter has the greatest effect on the welds made and results in the entire product being taken out of service.
{"title":"EVALUATION OF FILLET WELDS PROPERTIES PERFORMED BY COLD METAL TRANSFER ROBOTIC METAL ACTIVE GAS WELDING TECHNOLOGY","authors":"J. Brezinová, J. Hašuľ","doi":"10.3846/transport.2023.19084","DOIUrl":"https://doi.org/10.3846/transport.2023.19084","url":null,"abstract":"The article is the result of research evaluating the quality of fillet welds used in the production of rear seat backrests for passenger cars and manufactured robotically by Cold Metal Transfer (CMT) robotic Metal Active Gas (MAG) welding. When robotizing the process, parameters such as the speed of the process itself, accuracy and quality of the welded joints are important. Dual-phase ferritic-martensitic steel HCX 590X was used for the experiment and four weld nodes were evaluated. The quality of welded joints was evaluated by visual and capillary methods. Based on the metallographic analysis, the weld depth of the weld root was evaluated. The measured values were subsequently processed by statistical method ANalysis Of Variance (ANOVA). The research confirmed that the final quality of the welds depends on the depth of the weld root weld into the Base Material (BM). This parameter has the greatest effect on the welds made and results in the entire product being taken out of service.","PeriodicalId":23260,"journal":{"name":"Transport","volume":"26 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89594943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-06DOI: 10.3846/transport.2023.19181
A. Jaržemskis, Darius Bazaras, Ilona Jaržemskienė
This article presents a study conducted in the Town of Šiauliai with a population of 100 thousand, located in the Republic of Lithuania, where the market economy has been operating for 32 years and which is a member of the European Union for 20 years. In the town, the share of commuting travels by car is significantly higher than by public transport. Since the availability of the public transport network is identified in scientific publications as one of the many criteria for choosing public transport, it was decided to conduct a study and check to what extent the availability of the public transport network determines the choice to travel by bus or car. The research hypothesizes that residents who live in neighbourhoods with worse access to bus routes and stops choose more cars than those who live in neighbourhoods with better access to public transport. The results of the study showed that residents choose to travel by bus or car regardless of the availability of the route network. It was found that the origin–destination pairs and relative proportions of those commuting to work match both those traveling by car and by bus. The results of this study may not necessarily be the same in Western European cities or towns. The main limitation of this article is that the trip matrices were compiled from population survey data, as statistical information on origin–destination pairs in Town of Šiauliai is not regularly collected.
{"title":"COMMUTING PREFERENCES IN EASTERN EUROPE: CASE STUDY IN TOWN OF ŠIAULIAI","authors":"A. Jaržemskis, Darius Bazaras, Ilona Jaržemskienė","doi":"10.3846/transport.2023.19181","DOIUrl":"https://doi.org/10.3846/transport.2023.19181","url":null,"abstract":"This article presents a study conducted in the Town of Šiauliai with a population of 100 thousand, located in the Republic of Lithuania, where the market economy has been operating for 32 years and which is a member of the European Union for 20 years. In the town, the share of commuting travels by car is significantly higher than by public transport. Since the availability of the public transport network is identified in scientific publications as one of the many criteria for choosing public transport, it was decided to conduct a study and check to what extent the availability of the public transport network determines the choice to travel by bus or car. The research hypothesizes that residents who live in neighbourhoods with worse access to bus routes and stops choose more cars than those who live in neighbourhoods with better access to public transport. The results of the study showed that residents choose to travel by bus or car regardless of the availability of the route network. It was found that the origin–destination pairs and relative proportions of those commuting to work match both those traveling by car and by bus. The results of this study may not necessarily be the same in Western European cities or towns. The main limitation of this article is that the trip matrices were compiled from population survey data, as statistical information on origin–destination pairs in Town of Šiauliai is not regularly collected.","PeriodicalId":23260,"journal":{"name":"Transport","volume":"39 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79151071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-28DOI: 10.3846/transport.2023.17074
A. Tubis, S. Werbińska-Wojciechowska
Reliable and effective selection of logistic handling operator is a particularly demanding process due to the short reaction time or high level of accompanying stress. Moreover, diversification of transported cargo makes use of classical indicators and methods of carrier selection highly unsatisfactory for decision-makers. To solve this problem, managers are seeking multi-criteria decision methods that improve the decision-making process related to the selection of the carrier and reduce the risk indicator related to the incorrect implementation of the transport order. Thus, in this paper, we present a Multi-Criteria Decision-Making (MCDM) approach for selecting logistic handling operators under partial or incomplete information (uncertainty) and taking into account the different type of transported cargo. The proposed approach comprises 2 main steps. In the 1st step, we identify the input parameters, mainly connected with criteria for carrier selection depending on the type of transported cargo. In the 2nd step, experts provide linguistic ratings to the potential alternatives against the selected criteria and the best alternative is chosen. At this stage, the fuzzy Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) approach is used. Later, the applicability of the developed method is presented based on the chosen case company. The comparison of classical and fuzzy approaches to decision-making process is also given.
{"title":"FUZZY TOPSIS IN SELECTING LOGISTIC HANDLING OPERATOR: CASE STUDY FROM POLAND","authors":"A. Tubis, S. Werbińska-Wojciechowska","doi":"10.3846/transport.2023.17074","DOIUrl":"https://doi.org/10.3846/transport.2023.17074","url":null,"abstract":"Reliable and effective selection of logistic handling operator is a particularly demanding process due to the short reaction time or high level of accompanying stress. Moreover, diversification of transported cargo makes use of classical indicators and methods of carrier selection highly unsatisfactory for decision-makers. To solve this problem, managers are seeking multi-criteria decision methods that improve the decision-making process related to the selection of the carrier and reduce the risk indicator related to the incorrect implementation of the transport order. Thus, in this paper, we present a Multi-Criteria Decision-Making (MCDM) approach for selecting logistic handling operators under partial or incomplete information (uncertainty) and taking into account the different type of transported cargo. The proposed approach comprises 2 main steps. In the 1st step, we identify the input parameters, mainly connected with criteria for carrier selection depending on the type of transported cargo. In the 2nd step, experts provide linguistic ratings to the potential alternatives against the selected criteria and the best alternative is chosen. At this stage, the fuzzy Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) approach is used. Later, the applicability of the developed method is presented based on the chosen case company. The comparison of classical and fuzzy approaches to decision-making process is also given.","PeriodicalId":23260,"journal":{"name":"Transport","volume":"102 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75876350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-28DOI: 10.3846/transport.2023.18666
Algimantas Danilevičius, M. Karpenko, V. Krivanek
The noise pollution inside urban areas is one of the common problems for the inhabitants. The different levels of a noise are generated from the large amount of sources, including traffic flow on a road of urban areas. Therefore, it is essential to measure and evaluate the road traffic noise in urban areas and its population exposure in order to obtain models of a traffic noise as well as the noise mapping. The current research includes establishing a traffic noise from the different types of vehicles caused by the speed in urban areas and different road pavements (dry, wet and covered with a snow) with generalising the obtained data for more accurate using in future traffic noise models and the noise mapping. The study region is Vilnius (Lithuania), the speed range for different categories of the vehicles in the collected data is 40…130 km/h, with wide ranges of a noise level 20…180 dB. The approach presented in this research of experimental measurements is based on Statistical Pass-By (SPB) method with data proceeding upon implementation of Pearson correlation coefficient. In course of the analysis of the obtained results, it was found that the level of the curves of noise depends on the vehicles’ speed what corresponds to the best-measured values and can be used in the traffic noise models and the noise mapping.
{"title":"RESEARCH ON THE NOISE POLLUTION FROM DIFFERENT VEHICLE CATEGORIES IN THE URBAN AREA","authors":"Algimantas Danilevičius, M. Karpenko, V. Krivanek","doi":"10.3846/transport.2023.18666","DOIUrl":"https://doi.org/10.3846/transport.2023.18666","url":null,"abstract":"The noise pollution inside urban areas is one of the common problems for the inhabitants. The different levels of a noise are generated from the large amount of sources, including traffic flow on a road of urban areas. Therefore, it is essential to measure and evaluate the road traffic noise in urban areas and its population exposure in order to obtain models of a traffic noise as well as the noise mapping. The current research includes establishing a traffic noise from the different types of vehicles caused by the speed in urban areas and different road pavements (dry, wet and covered with a snow) with generalising the obtained data for more accurate using in future traffic noise models and the noise mapping. The study region is Vilnius (Lithuania), the speed range for different categories of the vehicles in the collected data is 40…130 km/h, with wide ranges of a noise level 20…180 dB. The approach presented in this research of experimental measurements is based on Statistical Pass-By (SPB) method with data proceeding upon implementation of Pearson correlation coefficient. In course of the analysis of the obtained results, it was found that the level of the curves of noise depends on the vehicles’ speed what corresponds to the best-measured values and can be used in the traffic noise models and the noise mapping.","PeriodicalId":23260,"journal":{"name":"Transport","volume":"12 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85453031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-31DOI: 10.3846/transport.2022.17065
Zaigang Chen, Jie Zhang, Kaiyun Wang, Peng-fei Liu
Rail corrugation is usually generated in modern railway transportations, such as high-speed railway, urban railway, and heavy-haul railway. It is one of the major excitations to the wheel–rail dynamic interaction, which will cause extra vibration and noise, failures, or even risk of derailment to the vehicle and its components. A dynamics model of a heavy-haul locomotive considering the traction power from the electric motor to the wheelset through gear transmission is employed to investigate the nonlinear dynamic responses of the locomotive. This dynamics model couples the motions of the vehicle, the track, and the gear transmission together. In this dynamics model, excitations from the rail corrugation, the nonlinear wheel–rail contact, the time-varying mesh stiffness, and the nonlinear gear backlash are considered. Then, numerical simulations are performed to reveal the dynamic responses of the locomotive. The calculated results indicate that different nonlinear phenomenon can be observed under the excitation of the rail corrugation with different amplitude and wavelength. The high frequency vibrations excited by the time-varying mesh stiffness are usually modulated by the low frequency vibrations caused by the rail corrugation. However, this is likely to vanish under the chaotic conditions with some corrugation wavelength. The vibration level of the vehicle and the gear transmission increases generally with the corrugation amplitude. However, some corrugation lengths have been found to be more responsible for the vibration of the dynamics system, which should be concerned greatly during the locomotive operation. Meanwhile, involvement of gear transmission systems will cause different dynamic responses between the wheelsets under rail corrugation and gear mesh excitations.
{"title":"NONLINEAR DYNAMIC RESPONSES OF LOCOMOTIVE EXCITED BY RAIL CORRUGATION AND GEAR TIME-VARYING MESH STIFFNESS","authors":"Zaigang Chen, Jie Zhang, Kaiyun Wang, Peng-fei Liu","doi":"10.3846/transport.2022.17065","DOIUrl":"https://doi.org/10.3846/transport.2022.17065","url":null,"abstract":"Rail corrugation is usually generated in modern railway transportations, such as high-speed railway, urban railway, and heavy-haul railway. It is one of the major excitations to the wheel–rail dynamic interaction, which will cause extra vibration and noise, failures, or even risk of derailment to the vehicle and its components. A dynamics model of a heavy-haul locomotive considering the traction power from the electric motor to the wheelset through gear transmission is employed to investigate the nonlinear dynamic responses of the locomotive. This dynamics model couples the motions of the vehicle, the track, and the gear transmission together. In this dynamics model, excitations from the rail corrugation, the nonlinear wheel–rail contact, the time-varying mesh stiffness, and the nonlinear gear backlash are considered. Then, numerical simulations are performed to reveal the dynamic responses of the locomotive. The calculated results indicate that different nonlinear phenomenon can be observed under the excitation of the rail corrugation with different amplitude and wavelength. The high frequency vibrations excited by the time-varying mesh stiffness are usually modulated by the low frequency vibrations caused by the rail corrugation. However, this is likely to vanish under the chaotic conditions with some corrugation wavelength. The vibration level of the vehicle and the gear transmission increases generally with the corrugation amplitude. However, some corrugation lengths have been found to be more responsible for the vibration of the dynamics system, which should be concerned greatly during the locomotive operation. Meanwhile, involvement of gear transmission systems will cause different dynamic responses between the wheelsets under rail corrugation and gear mesh excitations.","PeriodicalId":23260,"journal":{"name":"Transport","volume":"112 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87799687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-31DOI: 10.3846/transport.2022.18172
Chentong Bian, Guo-dong Yin, Liwei Xu, Ning Zhang
To reduce rear-end collision risks and improve traffic safety, a novel rear-end collision escape algorithm is proposed for intelligent vehicles supported by vehicular communication. Numerous research has been carried out on rear-end collision avoidance. Most of these studies focused on maintaining a safe front clearance of a vehicle while only few considered the vehicle’s rear clearance. However, an intelligent vehicle may be collided by a following vehicle due to wrong manoeuvres of an unskilled driver of the following vehicle. Hence, it is essential for an intelligent vehicle to maintain a safe rear clearance when there is potential for a rear-end collision caused by a following vehicle. In this study, a rear-end collision escape algorithm is proposed to prevent rear-end collisions by a following vehicle considering both straight and curved roads. A trajectory planning method is designed according to the motions of the considered intelligent vehicle and the corresponding adjacent vehicles. The successive linearization and the Model Predictive Control (MPC) algorithms are used to design a motion controller in the proposed algorithm. Simulations were performed to demonstrate the effectiveness of the proposed algorithm. The results show that the proposed algorithm is effective in preventing rear-end collisions caused by a following vehicle.
{"title":"REAR-END COLLISION ESCAPE ALGORITHM FOR INTELLIGENT VEHICLES SUPPORTED BY VEHICULAR COMMUNICATION","authors":"Chentong Bian, Guo-dong Yin, Liwei Xu, Ning Zhang","doi":"10.3846/transport.2022.18172","DOIUrl":"https://doi.org/10.3846/transport.2022.18172","url":null,"abstract":"To reduce rear-end collision risks and improve traffic safety, a novel rear-end collision escape algorithm is proposed for intelligent vehicles supported by vehicular communication. Numerous research has been carried out on rear-end collision avoidance. Most of these studies focused on maintaining a safe front clearance of a vehicle while only few considered the vehicle’s rear clearance. However, an intelligent vehicle may be collided by a following vehicle due to wrong manoeuvres of an unskilled driver of the following vehicle. Hence, it is essential for an intelligent vehicle to maintain a safe rear clearance when there is potential for a rear-end collision caused by a following vehicle. In this study, a rear-end collision escape algorithm is proposed to prevent rear-end collisions by a following vehicle considering both straight and curved roads. A trajectory planning method is designed according to the motions of the considered intelligent vehicle and the corresponding adjacent vehicles. The successive linearization and the Model Predictive Control (MPC) algorithms are used to design a motion controller in the proposed algorithm. Simulations were performed to demonstrate the effectiveness of the proposed algorithm. The results show that the proposed algorithm is effective in preventing rear-end collisions caused by a following vehicle.","PeriodicalId":23260,"journal":{"name":"Transport","volume":"120 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77419407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-31DOI: 10.3846/transport.2022.18376
M. Keshavarz-Ghorabaee, M. Amiri, E. Zavadskas, Zenonas Turskis, J. Antuchevičienė
Studies related to transportation planning and development have been in the center of activities of many researchers in the past decades. Road congestions issues, economic problems, health problems and environmental problems are some examples of complex problems that can be caused by urban and public transportation in big cities. Evaluating urban and public transportation systems could help to reach effective solutions to overcome these issues. This article presents a short bibliographic review of some recent studies on Multi-Criteria Decision-Making (MCDM) approaches for evaluating urban and public transportation systems. To this aim, Scopus was chosen as the database for making a search on journal articles. Scopus is trusted by major institutions in the world, and all journals covered in this database are inspected for sufficiently high quality each year. The search was made on the journal articles from 2017 to 2022 (July). The analyses presented in this study show that the Analytic Hierarchy Process (AHP) method is the most used method, which has been applied to different studies in the field of urban and public transportation systems based on MCDM approaches. According to the analysis of the number of articles, Turkey is ranked 1st among different countries, and “Budapest University of Technology and Economics” (Hungary) is 1st in the ranking of institutions. Moreover, most of the articles have been published within the “social sciences” subject area. The recent trend in different studies on urban and public transportation systems shows the importance of using MCDM approaches in this field. Moreover, noticeable employment of fuzzy sets in several studies is a point that can shows the significant role of uncertainty in dealing with this type of problems.
{"title":"MCDM APPROACHES FOR EVALUATING URBAN AND PUBLIC TRANSPORTATION SYSTEMS: A SHORT REVIEW OF RECENT STUDIES","authors":"M. Keshavarz-Ghorabaee, M. Amiri, E. Zavadskas, Zenonas Turskis, J. Antuchevičienė","doi":"10.3846/transport.2022.18376","DOIUrl":"https://doi.org/10.3846/transport.2022.18376","url":null,"abstract":"Studies related to transportation planning and development have been in the center of activities of many researchers in the past decades. Road congestions issues, economic problems, health problems and environmental problems are some examples of complex problems that can be caused by urban and public transportation in big cities. Evaluating urban and public transportation systems could help to reach effective solutions to overcome these issues. This article presents a short bibliographic review of some recent studies on Multi-Criteria Decision-Making (MCDM) approaches for evaluating urban and public transportation systems. To this aim, Scopus was chosen as the database for making a search on journal articles. Scopus is trusted by major institutions in the world, and all journals covered in this database are inspected for sufficiently high quality each year. The search was made on the journal articles from 2017 to 2022 (July). The analyses presented in this study show that the Analytic Hierarchy Process (AHP) method is the most used method, which has been applied to different studies in the field of urban and public transportation systems based on MCDM approaches. According to the analysis of the number of articles, Turkey is ranked 1st among different countries, and “Budapest University of Technology and Economics” (Hungary) is 1st in the ranking of institutions. Moreover, most of the articles have been published within the “social sciences” subject area. The recent trend in different studies on urban and public transportation systems shows the importance of using MCDM approaches in this field. Moreover, noticeable employment of fuzzy sets in several studies is a point that can shows the significant role of uncertainty in dealing with this type of problems.","PeriodicalId":23260,"journal":{"name":"Transport","volume":"77 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80245883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-22DOI: 10.3846/transport.2022.18331
R. Cieślicki, M. Karpenko
Gear pumps are widely used in transport machines not only in hydraulic drive systems, but also in lubrication and fuel systems. A positive displacement pump converts mechanical energy into pressure energy stored in the liquid, which it transports to the hydraulic cylinder or motor. The efficiency of this process depends on the efficiency of the system components, including the efficiency of the pump, which depends on the amount of internal leakage through the gaps between the high and low pressure sides. The larger the gaps, the lower the volumetric efficiency. This article presents an investigations of impact of pump deformations on circumferential gap height. The article presents a three-dimensional model of an external gear pump using Finite Element Method (FEM) during operating conditions. The model reflects pumping operation at discharge pressures up to 32 MPa and it was validated against strain measurements of pump casing. The simulation results indicate that the pump casing becomes deformed due to pressure, causing a significant increase in the height of the circumferential gap. The increase of the discharge pressure from 8 to 32 MPa causes more than twofold local increase in the height of the circumferential gap. The obtained results indicate that for the correct modelling of the flow generated by gear pumps, it is necessary to consider the change in the size of the gaps resulting from the deformation of the pump.
{"title":"AN INVESTIGATION OF THE IMPACT OF PUMP DEFORMATIONS ON CIRCUMFERENTIAL GAP HEIGHT AS A FACTOR INFLUENCING VOLUMETRIC EFFICIENCY OF EXTERNAL GEAR PUMPS","authors":"R. Cieślicki, M. Karpenko","doi":"10.3846/transport.2022.18331","DOIUrl":"https://doi.org/10.3846/transport.2022.18331","url":null,"abstract":"Gear pumps are widely used in transport machines not only in hydraulic drive systems, but also in lubrication and fuel systems. A positive displacement pump converts mechanical energy into pressure energy stored in the liquid, which it transports to the hydraulic cylinder or motor. The efficiency of this process depends on the efficiency of the system components, including the efficiency of the pump, which depends on the amount of internal leakage through the gaps between the high and low pressure sides. The larger the gaps, the lower the volumetric efficiency. This article presents an investigations of impact of pump deformations on circumferential gap height. The article presents a three-dimensional model of an external gear pump using Finite Element Method (FEM) during operating conditions. The model reflects pumping operation at discharge pressures up to 32 MPa and it was validated against strain measurements of pump casing. The simulation results indicate that the pump casing becomes deformed due to pressure, causing a significant increase in the height of the circumferential gap. The increase of the discharge pressure from 8 to 32 MPa causes more than twofold local increase in the height of the circumferential gap. The obtained results indicate that for the correct modelling of the flow generated by gear pumps, it is necessary to consider the change in the size of the gaps resulting from the deformation of the pump.","PeriodicalId":23260,"journal":{"name":"Transport","volume":"1 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91275202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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