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Détails du magazine
Format
Magazine
eISSN
1407-6179
Première publication
20 Mar 2000
Période de publication
4 fois par an
Langues
Anglais

Chercher

Volume 16 (2015): Edition 2 (June 2015)

Détails du magazine
Format
Magazine
eISSN
1407-6179
Première publication
20 Mar 2000
Période de publication
4 fois par an
Langues
Anglais

Chercher

0 Articles
Accès libre

Portable Telematic System as an Effective Traffic Flow Management in Workzones

Publié en ligne: 18 Apr 2015
Pages: 99 - 106

Résumé

Abstract

Traffic infrastructure localities with temporal restrictions for example due to reconstructions, or modernization, are important aspects influencing the traffic safety and traffic flow. On the basis of our research, we can identify main factors, which generate travel time loses, and which often cause traffic accidents in bottlenecks. First of all, it is improper late merge, speeding, tailgating, lower tolerance and consideration to other road users. Nervousness and ignorance of drivers also play an important role in generation of traffic congestions, lower level of service and resulting external economic loses. One of the tools eliminating the traffic restriction negative impacts is usage of portable telematics systems. In 2011 to 2013,project ViaZONE was in progress, which was to design an intelligent system with the aim to eliminate the mentioned risks and reduce economic losses generated by traffic congestions. Using available data and information, we have proved profitability and cost-effectiveness of dynamic systems for traffic control of work zones. Regarding traffic management, the system showed some problems due to indisciplined drivers and the system proved that speeding in these hazardous road segments is a common practice which caused accidents and congestions.

Keywords

  • Workzones
  • Traffic management
  • accident
  • congestion
  • detectors
  • portable variable message signs
Accès libre

Air Cargo Development in the Regional Airports of the Baltic Sea Region Through Road Feeder Services

Publié en ligne: 18 Apr 2015
Pages: 107 - 116

Résumé

Abstract

As issued in the Competition Policy Brief on the new state aid rules for a competitive aviation industry by the Competition Directorate-General of the European Commission in February 20141, it will be more difficult for unprofitable airports, to obtain financial public subsidies on EU, national or regional level. Although the positive impact of small airports on the regional development and general accessibility was mentioned, still the operating aid to the airports shall be cut out over a maximum of 10 years. It has been further stated that the vast majority of small and regional airports experience problems to cover their running operative costs, as a result from an intensive market competition and overlapping of airports’ catchment areas preventing even some promising airports from growth. Public subsidies are mostly used by the airport management for infrastructural investments, to cover operating losses or to attract price-sensitive airlines. Herewith, among other things, the EU Commission is pointing out at the lack of cooperation structures and network strategies among the regional airports and at rather isolated and individual approach during elaboration of the airport development scenarios. However, the Competition Policy Brief permits public aid to regional airports, among other things if there is sufficient transports need to establish transition periods for small airports; the need for more flexibility of the regional airports in the remote areas has been underlined. The EU Commission is expecting herewith not to close the regional airports, but to stimulate them to operate on cost efficient and profitable basis, and that only the most inefficient airports will be closed.

To cope with the upcoming challenges the regional airports are demanded now to revaluate and reconsider their future development plans. While focusing on the passenger traffic many regional airports ignore or underestimate the benefits of the airfreight market. Although the air cargo has rather a low volume, but very high revenue yield part. Business internationalization is one of the important driving forces for the airfreight nowadays as well as decreasing air transport costs due to improving efficiency and growing competition among the air carriers. Most regional airports in the Baltic Sea region that act totally isolated, do not have a clear picture of the current situation on the international air cargo market, its future perspectives and sustainable development plans. Trying to meet the market demand, the regional airports are making huge and unjustified investments, e.g. improving airport infrastructure. It is not clear till now which elements of the Pan-Baltic cargo market could be managed as an alternative revenue yielding services for consolidated operation by air or what infrastructure is needed to provide the opportunity for an optimal economic mix of road-rail-air-sea transport? Nowadays, to a large degree air cargo traffic relies on scheduled, frequent passenger services in hub-and-spoke as well as in point-to-point traffic. Regional airports are presently suffering from a lack of scheduled uplift capacity. The volume currently transported by air in the regional airports is almost entirely based on the occasional charter flights. However, the growth of the air cargo business is likely to be based not only on cargo charters, but to a larger extend on truck-based services for transit shipments. Onward transportation by truck may occur on road feeder service, so called “flying trucks”, where a real truck substitutes a flight. “Flying trucks” are having flight numbers etc., therefore they must be prioritized in many ways in the BSR transport policy.

This paper investigates the role of Road Feeder Services concept (thereafter named here as “Flying Truck”) as an optional freight value proposition for the development of the regional airports and their possible participation in the air cargo market as a supplement instrument to generate additional revenue, thus making the airports more profitable and attractive.

Keywords

  • Air cargo
  • Road Feeder Services (RFS)
  • regional airports
  • multimodality
  • air-road concept
Accès libre

Satellite Monitoring Systems for Shipping and Offshore Oil and Gas Industry in the Baltic Sea

Publié en ligne: 18 Apr 2015
Pages: 117 - 126

Résumé

Abstract

Shipping activities, oil production and transport in the sea, oil handled in harbors, construction and exploitation of offshore oil and gas pipelines have a number of negative impacts on the marine environment and coastal zone of the seas. In 2004-2014 we elaborated several operational satellite monitoring systems for oil and gas companies in Russia and performed integrated satellite monitoring of the ecological state of coastal waters in the Baltic, Black, Caspian, and Kara seas, which included observation of oil pollution, suspended matter, and algae bloom at a fully operational mode. These monitoring systems differ from the existing ones by the analysis of a wide spectrum of satellite, meteorological and oceanographic data, as well as by a numerical modeling of oil spill transformation and transport in real weather conditions. Our experience in the Baltic Sea includes: (1) integrated satellite monitoring of oil production at the LUKOIL-KMN Ltd. D-6 oil rig in the Southeastern Baltic Sea (Kravtsovskoe oil field) in 2004-2014; (2) integrated satellite monitoring of the “Nord Stream” underwater gas pipeline construction and exploitation in the Gulf of Finland (2010-2013); (3) numerical modeling of risks of oil pollution caused by shipping along the main maritime shipping routes in the Gulf of Finland, the Baltic Proper, and in the Southeastern Baltic Sea; (4) numerical modeling of risks of oil pollution caused by oil production at D-6 oil rig and oil transportation on shore via the connecting underwater oil pipeline.

Keywords

  • the Baltic Sea
  • oil pollution
  • satellite monitoring
  • shipping
  • oil and gas pipelines
  • environmental risk assessment
  • numerical modeling
Accès libre

Braking Deceleration Measurement Using the Video Analysis of Motions by Sw Tracker

Publié en ligne: 18 Apr 2015
Pages: 127 - 137

Résumé

Abstract

This contribution deals with the issue of car braking, particularly with the one of M1 category. Braking deceleration measurement of the vehicle Mazda 3 MPS was carried out by the declerograph XL MeterTM Pro. The main aim of the contribution is to perform comparison of the process of braking deceleration between the decelograph and the new alternative method of video analysis and to subsequently examine these processes. The test took place at the Rosina airfield, the airstrip in a small village nearby the town of Žilina. The last part of this paper presents the results, evlauation and comparison of the measurements carried out.

Keywords

  • braking deceleration
  • braking time
  • braking distance
  • analysis
  • decelograph XL MeterTM Pro
  • SW Tracker
Accès libre

Identifyingy the Utility Function of Transport Services From Stated Preferences

Publié en ligne: 18 Apr 2015
Pages: 138 - 144

Résumé

Abstract

The aim of this study was to analyze the modal shift of passengers by analyzing their preferences. If the preferences of passengers are known it is possible to build up mathematically their utility function. This is the statistically correct way to simulate the modal shift of the investigated area. To capture the preferences of passengers stated preference method was used in online questionnaire. Five key factors were identified (from the point of passengers): travel cost, travel time, comfort, safety and environmental efficiency. In order to decrease the number of questions three levels were predefined these three questions made the base of the choice model. Every replier got three alternatives and they were told to choose the best for themselves. From the results of the questionnaire the formulas and the parameters of the mode choice utility function was derived. With the help of statistical sample an exponential utility function showed the best matching. For the validation process a probability model was set up to be compared to the proportions of the utilities. With this utility function it is possible to handle the changes in possible future transport services. Based on the introduced statistical approach the described method can be used to identify the effect of transport modes on regional development and tourism. The revealed utility function can help to develop proper regional development plans.

Keywords

  • Stated preference
  • Utility function
  • Modal shift
  • transport and tourism
Accès libre

Numerical Simulation of Moving Load on Concrete Pavements

Publié en ligne: 18 Apr 2015
Pages: 145 - 157

Résumé

Abstract

The knowledge of the development with time of the strain and stress states in pavement structures is needed in the solution of various engineering tasks as the design fatigue lifetime reliability maintenance and structure development. The space computing model of the truck TATRA 815 is introduced. The pavement computing model is created in the sense of Kirchhof theory of the thin slab on elastic foundation. The goal of the calculation is to obtain the vertical deflection in the middle of the slab and the time courses of vertical tire forces. The equations of motion are derived in the form of differential equations. The assumption about the shape of the slab deflection area is adopted. The equations of the motion are solved numerically in the environment of program system MATLAB. The dependences following the influence of various parameters (speed of vehicle motion, stiffness of subgrade, slab thickness, road profile) on the pavement vertical deflections and the vertical tire forces are introduced. The results obtained from the plate computing model are compared with the results obtained by the FEM analysis. The outputs of the numerical solution in the time domain can be transformed into a frequency domain and subsequently used to solve various engineering tasks.

Keywords

  • numerical simulation
  • moving load
  • computing models
  • concrete pavements
  • dynamic
  • tire forces
Accès libre

Cyclic Fracture Toughness of Railway Axle and Mechanisms of its Fatigue Fracture

Publié en ligne: 18 Apr 2015
Pages: 158 - 166

Résumé

Abstract

The main regularities in fatigue fracture of the railway axle material - the OSL steel - are found in this paper. Micromechanisms of fatigue crack propagation are described and systematized, and a physical-mechanical interpretation of the relief morphology at different stages of crack propagation is proposed for fatigue cracks in specimens cut out of the surface, internal and central layers of the axle.

Keywords

  • fatigue
  • fracture
  • mechanisms of damage
  • stress-strain state
  • railway axle
0 Articles
Accès libre

Portable Telematic System as an Effective Traffic Flow Management in Workzones

Publié en ligne: 18 Apr 2015
Pages: 99 - 106

Résumé

Abstract

Traffic infrastructure localities with temporal restrictions for example due to reconstructions, or modernization, are important aspects influencing the traffic safety and traffic flow. On the basis of our research, we can identify main factors, which generate travel time loses, and which often cause traffic accidents in bottlenecks. First of all, it is improper late merge, speeding, tailgating, lower tolerance and consideration to other road users. Nervousness and ignorance of drivers also play an important role in generation of traffic congestions, lower level of service and resulting external economic loses. One of the tools eliminating the traffic restriction negative impacts is usage of portable telematics systems. In 2011 to 2013,project ViaZONE was in progress, which was to design an intelligent system with the aim to eliminate the mentioned risks and reduce economic losses generated by traffic congestions. Using available data and information, we have proved profitability and cost-effectiveness of dynamic systems for traffic control of work zones. Regarding traffic management, the system showed some problems due to indisciplined drivers and the system proved that speeding in these hazardous road segments is a common practice which caused accidents and congestions.

Keywords

  • Workzones
  • Traffic management
  • accident
  • congestion
  • detectors
  • portable variable message signs
Accès libre

Air Cargo Development in the Regional Airports of the Baltic Sea Region Through Road Feeder Services

Publié en ligne: 18 Apr 2015
Pages: 107 - 116

Résumé

Abstract

As issued in the Competition Policy Brief on the new state aid rules for a competitive aviation industry by the Competition Directorate-General of the European Commission in February 20141, it will be more difficult for unprofitable airports, to obtain financial public subsidies on EU, national or regional level. Although the positive impact of small airports on the regional development and general accessibility was mentioned, still the operating aid to the airports shall be cut out over a maximum of 10 years. It has been further stated that the vast majority of small and regional airports experience problems to cover their running operative costs, as a result from an intensive market competition and overlapping of airports’ catchment areas preventing even some promising airports from growth. Public subsidies are mostly used by the airport management for infrastructural investments, to cover operating losses or to attract price-sensitive airlines. Herewith, among other things, the EU Commission is pointing out at the lack of cooperation structures and network strategies among the regional airports and at rather isolated and individual approach during elaboration of the airport development scenarios. However, the Competition Policy Brief permits public aid to regional airports, among other things if there is sufficient transports need to establish transition periods for small airports; the need for more flexibility of the regional airports in the remote areas has been underlined. The EU Commission is expecting herewith not to close the regional airports, but to stimulate them to operate on cost efficient and profitable basis, and that only the most inefficient airports will be closed.

To cope with the upcoming challenges the regional airports are demanded now to revaluate and reconsider their future development plans. While focusing on the passenger traffic many regional airports ignore or underestimate the benefits of the airfreight market. Although the air cargo has rather a low volume, but very high revenue yield part. Business internationalization is one of the important driving forces for the airfreight nowadays as well as decreasing air transport costs due to improving efficiency and growing competition among the air carriers. Most regional airports in the Baltic Sea region that act totally isolated, do not have a clear picture of the current situation on the international air cargo market, its future perspectives and sustainable development plans. Trying to meet the market demand, the regional airports are making huge and unjustified investments, e.g. improving airport infrastructure. It is not clear till now which elements of the Pan-Baltic cargo market could be managed as an alternative revenue yielding services for consolidated operation by air or what infrastructure is needed to provide the opportunity for an optimal economic mix of road-rail-air-sea transport? Nowadays, to a large degree air cargo traffic relies on scheduled, frequent passenger services in hub-and-spoke as well as in point-to-point traffic. Regional airports are presently suffering from a lack of scheduled uplift capacity. The volume currently transported by air in the regional airports is almost entirely based on the occasional charter flights. However, the growth of the air cargo business is likely to be based not only on cargo charters, but to a larger extend on truck-based services for transit shipments. Onward transportation by truck may occur on road feeder service, so called “flying trucks”, where a real truck substitutes a flight. “Flying trucks” are having flight numbers etc., therefore they must be prioritized in many ways in the BSR transport policy.

This paper investigates the role of Road Feeder Services concept (thereafter named here as “Flying Truck”) as an optional freight value proposition for the development of the regional airports and their possible participation in the air cargo market as a supplement instrument to generate additional revenue, thus making the airports more profitable and attractive.

Keywords

  • Air cargo
  • Road Feeder Services (RFS)
  • regional airports
  • multimodality
  • air-road concept
Accès libre

Satellite Monitoring Systems for Shipping and Offshore Oil and Gas Industry in the Baltic Sea

Publié en ligne: 18 Apr 2015
Pages: 117 - 126

Résumé

Abstract

Shipping activities, oil production and transport in the sea, oil handled in harbors, construction and exploitation of offshore oil and gas pipelines have a number of negative impacts on the marine environment and coastal zone of the seas. In 2004-2014 we elaborated several operational satellite monitoring systems for oil and gas companies in Russia and performed integrated satellite monitoring of the ecological state of coastal waters in the Baltic, Black, Caspian, and Kara seas, which included observation of oil pollution, suspended matter, and algae bloom at a fully operational mode. These monitoring systems differ from the existing ones by the analysis of a wide spectrum of satellite, meteorological and oceanographic data, as well as by a numerical modeling of oil spill transformation and transport in real weather conditions. Our experience in the Baltic Sea includes: (1) integrated satellite monitoring of oil production at the LUKOIL-KMN Ltd. D-6 oil rig in the Southeastern Baltic Sea (Kravtsovskoe oil field) in 2004-2014; (2) integrated satellite monitoring of the “Nord Stream” underwater gas pipeline construction and exploitation in the Gulf of Finland (2010-2013); (3) numerical modeling of risks of oil pollution caused by shipping along the main maritime shipping routes in the Gulf of Finland, the Baltic Proper, and in the Southeastern Baltic Sea; (4) numerical modeling of risks of oil pollution caused by oil production at D-6 oil rig and oil transportation on shore via the connecting underwater oil pipeline.

Keywords

  • the Baltic Sea
  • oil pollution
  • satellite monitoring
  • shipping
  • oil and gas pipelines
  • environmental risk assessment
  • numerical modeling
Accès libre

Braking Deceleration Measurement Using the Video Analysis of Motions by Sw Tracker

Publié en ligne: 18 Apr 2015
Pages: 127 - 137

Résumé

Abstract

This contribution deals with the issue of car braking, particularly with the one of M1 category. Braking deceleration measurement of the vehicle Mazda 3 MPS was carried out by the declerograph XL MeterTM Pro. The main aim of the contribution is to perform comparison of the process of braking deceleration between the decelograph and the new alternative method of video analysis and to subsequently examine these processes. The test took place at the Rosina airfield, the airstrip in a small village nearby the town of Žilina. The last part of this paper presents the results, evlauation and comparison of the measurements carried out.

Keywords

  • braking deceleration
  • braking time
  • braking distance
  • analysis
  • decelograph XL MeterTM Pro
  • SW Tracker
Accès libre

Identifyingy the Utility Function of Transport Services From Stated Preferences

Publié en ligne: 18 Apr 2015
Pages: 138 - 144

Résumé

Abstract

The aim of this study was to analyze the modal shift of passengers by analyzing their preferences. If the preferences of passengers are known it is possible to build up mathematically their utility function. This is the statistically correct way to simulate the modal shift of the investigated area. To capture the preferences of passengers stated preference method was used in online questionnaire. Five key factors were identified (from the point of passengers): travel cost, travel time, comfort, safety and environmental efficiency. In order to decrease the number of questions three levels were predefined these three questions made the base of the choice model. Every replier got three alternatives and they were told to choose the best for themselves. From the results of the questionnaire the formulas and the parameters of the mode choice utility function was derived. With the help of statistical sample an exponential utility function showed the best matching. For the validation process a probability model was set up to be compared to the proportions of the utilities. With this utility function it is possible to handle the changes in possible future transport services. Based on the introduced statistical approach the described method can be used to identify the effect of transport modes on regional development and tourism. The revealed utility function can help to develop proper regional development plans.

Keywords

  • Stated preference
  • Utility function
  • Modal shift
  • transport and tourism
Accès libre

Numerical Simulation of Moving Load on Concrete Pavements

Publié en ligne: 18 Apr 2015
Pages: 145 - 157

Résumé

Abstract

The knowledge of the development with time of the strain and stress states in pavement structures is needed in the solution of various engineering tasks as the design fatigue lifetime reliability maintenance and structure development. The space computing model of the truck TATRA 815 is introduced. The pavement computing model is created in the sense of Kirchhof theory of the thin slab on elastic foundation. The goal of the calculation is to obtain the vertical deflection in the middle of the slab and the time courses of vertical tire forces. The equations of motion are derived in the form of differential equations. The assumption about the shape of the slab deflection area is adopted. The equations of the motion are solved numerically in the environment of program system MATLAB. The dependences following the influence of various parameters (speed of vehicle motion, stiffness of subgrade, slab thickness, road profile) on the pavement vertical deflections and the vertical tire forces are introduced. The results obtained from the plate computing model are compared with the results obtained by the FEM analysis. The outputs of the numerical solution in the time domain can be transformed into a frequency domain and subsequently used to solve various engineering tasks.

Keywords

  • numerical simulation
  • moving load
  • computing models
  • concrete pavements
  • dynamic
  • tire forces
Accès libre

Cyclic Fracture Toughness of Railway Axle and Mechanisms of its Fatigue Fracture

Publié en ligne: 18 Apr 2015
Pages: 158 - 166

Résumé

Abstract

The main regularities in fatigue fracture of the railway axle material - the OSL steel - are found in this paper. Micromechanisms of fatigue crack propagation are described and systematized, and a physical-mechanical interpretation of the relief morphology at different stages of crack propagation is proposed for fatigue cracks in specimens cut out of the surface, internal and central layers of the axle.

Keywords

  • fatigue
  • fracture
  • mechanisms of damage
  • stress-strain state
  • railway axle