Surface Transportation Systems Research Articles

A Dynamic Decision Approach for Risk Analysis in Complex Projects

Underground metro tunnels present a popular solution to relieve the pressure of surface transportation systems worldwide. However, tunnel construction inevitably generates soil displacements and deformations, which may affect the safety performance of the surface road operation. This paper presents a systemic dynamic decision approach based on dynamic Bayesian networks (DBNs), aiming to provide guidelines for the dynamic safety analysis of the tunnel-induced road surface damage over time. The potential uncertainty and randomness underlying tunnel construction is modeled by following a discrete-time Markov chain process. A detailed step-by-step procedure is proposed, including risk/hazard identification, and DBN-based predictive and diagnostic analysis. A case study concerning the dynamic safety analysis in the construction of the Wuhan Yangtze Metro Tunnel is presented. Results demonstrate the feasibility of the proposed approach, as well as its application potential. The relationships between the DNB-based and BN-based approaches are further discussed based on the results. The proposed approach can be used as a decision tool to provide support for safety assurance in tunnel construction, and thus increase the likelihood of a successful project in a dynamic environment.

6th ACM SIGSPATIAL International Workshop on Computational Transportation Science

The 6th International Workshops on Computational Transportation Science was held in conjunction with the 21st ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems (ACM SIGSPATIAL GIS 2013) on November 5, 2013 in Orlando, FL. It brought together communities interested in the computation, knowledge discovery and technology policy aspects of surface transportation systems and the workshop series has become a platform for interdisciplinary dialog, reflected again in this year's proceedings.

A Security Based Greedy Method (SGMA) for VANETs in City Environment using Score Point Technique

The vehicular Ad-Hoc Networks (VANET) is constrained by high mobility of vehicles and frequent disconnections. The emerging adoption of wireless communications on surface transportation systems has generated extensive interest among researchers over the last several years. This research work deals with the crucial problems associated with routing in both city and urban environment due to false message receive from Vehicles. The main objectives of research, is to avoid the problem of false message attacks in VANET. To address this problem, the authors propose a Security Based Greedy Method (SGMA) specifically for a VANET and evaluate the performance using the NS2 simulator, which is used to add the functionality to validate message of each and every vehicle is secure and reliable. Results show that the proposed scheme will provide the score points of each vehicles, list the fake vehicles id and also SGMA operates properly in terms of packet delivery ratio. With the help of the score point received, the base station should identify the message is fake or not. The score point of vehicles is initialized in the Base station and the score point is stable or decreased depends on the feedback from receiver vehicle. The authors conclude that, the proposed work SGMA to make the network message more securable.

A Security Based Greedy Method SGMA for VANETs in City Environment using Score Point Technique

The vehicular Ad-Hoc Networks VANET is constrained by high mobility of vehicles and frequent disconnections. The emerging adoption of wireless communications on surface transportation systems has g...

U.S. Public Preferences for Weather and Road Condition Information

In 2008, the American Meteorological Society (AMS) Board on Enterprise Planning (BEP) established the Committee on Mobile Observations to discuss the application and utilization of mobile weather and road condition data in the context of supporting the weather and transportation communities and how these data could be used to improve safety and mobility across the nation's surface transportation system. The goal of the committee is to articulate a clear vision for mobile data that captures the immense opportunities for these data to improve road weather services and transportation safety and mobility. The Committee on Mobile Observations is engaged in numerous activities to accomplish its goal, which includes a nationwide survey of the traveling public to obtain better information on their preferences for and interests in obtaining weather and road condition information, their willingness to share vehicle data, and their willingness to pay for enhanced services. This paper outlines the results of the surv...

Quantitative evaluation of iron transport processes in the Sea of Okhotsk

Comprehensive observations of the iron (Fe) distribution in the western Sea of Okhotsk were conducted and revealed the existence of two Fe transport processes in the sub-polar marginal sea. One transport process is Fe loading from the Amur River and transport by the East Sakhalin Current (ESC), and the other is Fe transport by the intermediate water (part of which was reported by Nishioka et al., 2007). Here, we report on quantitative evaluations of these two Fe transport processes. The surface dissolved Fe (Diss-Fe) and low salinity water distribution clearly indicate the influence of Fe discharge from the Amur River and the Fe that is transported by the East Sakhalin Current. The amounts of total dissolvable Fe (TD-Fe) and Diss-Fe that cross the surface of the northeast Sakhalin coastal area are estimated at 9.0×108∼1.3×109gyr−1 and 1.0×108∼1.5×108gyr−1, respectively. Although the ESC surface transport system along the Sakhalin coast is effective, the length-scale estimation of TD-Fe transport indicated that only 1.5% of the Fe at the mouth of the Amur River reached 52°N, which may be due to scavenging by biological particulates. High Fe anomalies were observed at the bottom of the continental shelf and the shelf break along the Sakhalin coast. The extremely low temperature and low N* water indicate that Fe resuspension due to the reducing properties of sediment occurred on the shelf and that the Fe was introduced to Dense Shelf Water (DSW) by tidal mixing. We estimate that the amounts of TD-Fe and Diss-Fe involved in the DSW on the continental shelf are 8.8×1010∼2.5×1011gyr−1 and 2.3×109∼6.6×109gyr−1, respectively. Length-scale estimates of TD-Fe transport indicate that 20% of the TD-Fe on the continental shelf remained in the Kuril Basin; thus, the TD-Fe in the intermediate water was efficiently transported to the Kuril Basin. These results indicate that two orders of magnitude more Fe is derived from the continental shelf by the intermediate water than by surface water and that Fe is transported a greater distance by intermediate water than by the surface layer. Additionally, the Fe that reached the Kuril Straits was mixed by intensive tidal mixing and influenced the vertical profiles of the water columns on both sides of the Kuril Straits in the Kuril Basin and the Oyashio region. Our quantitative evaluation also indicates other Fe inputs around the Kuril Strait.

IGF-I Regulates Redox Status in Breast Cancer Cells by Activating the Amino Acid Transport Molecule xC−

Insulin-like growth factors (IGF) stimulate cell growth in part by increasing amino acid uptake. xCT (SLC7A11) encodes the functional subunit of the cell surface transport system xC(-), which mediates cystine uptake, a pivotal step in glutathione synthesis and cellular redox control. In this study, we show that IGF-I regulates cystine uptake and cellular redox status by activating the expression and function of xCT in estrogen receptor-positive (ER(+)) breast cancer cells by a mechanism that relies on the IGF receptor substrate-1 (IRS-1). Breast cancer cell proliferation mediated by IGF-I was suppressed by attenuating xCT expression or blocking xCT activity with the pharmacologic inhibitor sulfasalazine (SASP). Notably, SASP sensitized breast cancer cells to inhibitors of the type I IGF receptor (IGF-IR) in a manner reversed by the reactive oxygen species (ROS) scavenger N-acetyl-L-cysteine. Thus, IGF-I promoted the proliferation of ER(+) breast cancer cells by regulating xC(-) transporter function to protect cancer cells from ROS in an IRS-1-dependent manner. Our findings suggest that inhibiting xC(-) transporter function may synergize with modalities that target the IGF-IR to heighten their therapeutic effects.

Unified Driver Model simulation and its application to the automotive, rail and maritime domains

This paper describes the implementation of a model of a driver into a computerised numerical simulation. The model is developed to capture the essential characteristics and common aspects of cognition and behaviour of a human being in control of a “vehicle” in different surface transport systems, namely trains, cars and ships. The main functions of the simulation are discussed as well as the experiments carried out in different types of driving simulators to support the estimation of the parameters utilised in the numerical simulation. The validation processes carried out in the rail and maritime domains are also discussed together with a critical review of capacities and limitations of the proposed approach.

5th ACM SIGSPATIAL International Workshop on Computational Transportation Science

The 5 th International Workshop on Computational Transportation Science was held in conjunction with the 20th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems (ACM SIGSPATIAL GIS 2012) on November 6, 2012 in Redondo Beach, CA. It has brought together communities interested in the computation, knowledge discovery and technology policy aspects of surface transportation systems. Since the range of topics of a Computational Transportation Science reaches deep into multiple disciplines, such as computer science, urban and regional planning, civil engineering, geography, geoinformatics and related disciplines, the workshop series has become a platform for interdisciplinary dialog, reflected again in this year's proceedings.

Identification and Characterization of Putative Virulent Genes in Streptococcus equi ssp. zooepidemicus

Suppression subtractive hybridization (SSH) was performed with virulent strain ATCC35246 and avirulent strain ST171 to identify novel genes associated with virulence in Streptococcus equi ssp. zooepidemicus (SEZ). There were fourteen genomic regions that only presented in virulent strain ATCC35246. These regions encoded 14 proteins, some of them were homologous to proteins associated with cellular surface structure, molecular synthesis, energy metabolism, regulation, transport systems, and other unknown functions. Primers for 6 particular regions were designed from the already published SEZ sequence. Then, we used PCR to evaluate the distribution and conservation of these 6 DNA fragments in various SEZ strains collected from different sources, regions, groups, and times. The results showed that these 6 DNA fragments were widely distributed in SEZ strains, yet they were not existence in the avirulent strain ST171. Moreover, these fragments could not be detected in other Streptococcus groups.

Funding Major Airport Ground Access Projects

Funding projects to improve the intermodal connectivity between the surface transportation system and airports is often complicated by the need to draw on a range of funding programs and sources, each with its own project eligibility requirements and regulations. This paper presents seven case studies of the funding sources used for a range of major intermodal airport ground access projects in the United States that were completed in the past 12 years or were under construction. The case studies were undertaken as part of a recently completed research study that investigated collaborative funding strategies to facilitate airport ground access. The projects included a major intermodal center, two automated people mover links between airports and nearby rail stations, two airport access highway projects, and two extensions of rail transit systems to airports. The funding sources for the seven projects varied widely with the nature and location of the project. All seven projects involved some collaboration between local, state, and federal agencies in developing the funding plan for each project, although the number of agencies involved varied, with the larger projects generally having more agencies involved in providing funding. This experience suggests that developing a funding plan for such projects requires the involvement of a broad range of stakeholder agencies in planning and implementing the project.

A Risk Assessment Framework For Interconnected And Interdependent Surface Transport Networks

The functioning and viability of modern societies is heavily depended upon the continuous and uninterruptible operation of critical infrastructures. Surface transportation systems are in the heart of the daily lives of millions of citizens globally. As such, they are open and freely accessible by design and in the past have been exploited for terrorism attacks. Like many critical infrastructures, different multimodal and heterogeneous transportation networks are interconnected as integral part of larger synergistic systems forming a “network of networks”. These underlying and often concealed interconnections between network assets enable adverse effects to manifest at assets that are initially unaffected by a security incident. The present paper introduces a holistic Risk Assessment Framework for heterogeneous, transportation networks that is applicable at a strategic level, where risk is propagated between interconnected networks through an “Incident Propagation Matrix” taking into account the nature of the interconnection and the type of threat. The proposed methodology views and models the risk analysis process from the perspective of the network operator and emergency responders and emphasizes the reduction of the impacts on business continuity. DOI 10.5592/otmcj.2013.2.6 Research paper

The influence of operating loads on the state of stress and strain in selected load-bearing elements of a tower-type headgear structure / Wpływ obciążeń eksploatacyjnych na stan naprężenia oraz przemieszczenia wybranych elementów nośnych konstrukcji basztowej wieży szybowych

Abstract The headgear structure allows the conveyance to be moved over the shaft top to the loading (unloading) point, at the same time it keeps in place the rope pulleys while tower-type headgear structures also accommodate the entire winder installations. The headgear is where the final stage of the hoisting installation is located and where the surface transport systems begin. These aspects strongly impact the actual shape of the tower, its height and in some cases determine the design of the entire winding gear. In order that all the headgear functions should be provided, it is required that the ultimate state conditions should be maintained throughout its entire service life. In order to assess the critical service conditions, the computation procedure should be applied based on design loads and fatigue endurance parameters. The computations of characteristic loads acting on the headgear structure use the developed model of the system based on the dynamic analysis carried out for a specific case: a hoisting installation operated in one of the underground collieries in Poland. The maximal and minimal loads acting on a Koepe pulley and those required for the system operation are determined accordingly. The laws of dynamics provide a background for finding the forces and moments of forces acting in the components of the driving system (including the electric motors and pulley blocks) for the specified loading of the Koepe pulley. Underlying the numerical FEM model of the tower-type headgear structure are the technical specifications of the analysed object and FEM calculations followed by endurance analysis to find the state of stress in structural elements of the headgear under the typical service conditions. The results help in assessing how the design of the hoisting installation should impact on safety features of load-bearing elements in the headgear structure.

Investigating Benefits of IntelliDrive in Freeway Operations: Lane Changing Advisory Case Study

Abstract IntelliDrive, the integration of vehicles and the infrastructure through wireless communication, has generated great interest in the transportation community. It is widely expected that IntelliDrive will support significantly improved transportation operations. However, there have been few studies investigating (1) how IntelliDrive will be used to improve operations, and (2) how to estimate expected benefits of IntelliDrive operations applications. In this study, the research team investigated the application of IntelliDrive to address merging conflicts created by freeway on-ramps. Although merging conflicts contribute significantly to freeway congestion, transportation engineers have limited options with existing traffic surveillance and management tools. IntelliDrive offers the potential for more active management of the surface transportation system, providing capabilities that may be of significant benefit in ramp management. In this research, a lane changing advisory algorithm was developed ...

How shall we design the future vehicle for Chinese market

Surface transportation system is developing very fast in China and the number of vehicles is increasing quickly as well. This development creates a lot of problems on traffic safety and the number of accident is also increasing. In this paper, we made deep analysis of different possible causes of safety problems through three aspects: the traffic environment and infrastructure, in-vehicle information system design and the characteristics of drivers. There are many factors in each aspects may contribute to the transportation safety problems. Problems with infrastructure design and traffic design contribute over 50% of the traffic accident. Another important factor is that people has very little traffic safety concept and very weak on understanding the important of right behavior on the road. This paper has pointed the urgent needs to study the human factors in road and transportation system and vehicle HMI design, as there are very few such studies available in literature based on Chinese situation. The paper also proposed the needs to develop proactive educational system that can promote driver's understanding of traffic safety and to take the right action during drive.

Supporting Secure and Resilient Inland Waterways

The U.S. Department of Homeland Security's National Infrastructure Protection Program presents sector-specific planning objectives for protecting the nation's critical infrastructure and key resources. In concert with this objective, researchers at the University of Arkansas and Rutgers University are developing a prototype decision support system that integrates geographic information systems and freight movement models to provide a framework for cargo prioritization and off-loading during a sudden catastrophic closure of the national inland waterway. The project seeks to develop (a) a fundamental understanding of the resiliency of inland waterway transportation systems and the interdependence within and between transportation system components and (b) a decision system that will allow public and private parties to respond quickly to catastrophic waterway events. Researchers reviewed public data, published literature, and aerial imagery to ascertain terminal characteristics indicative of a potential for transferring barge cargo from the inland waterway to freight rail systems. A preliminary framework for assessing terminal suitability for intermodal transfer during a sudden catastrophic closure was developed. Findings suggest that the geographic dispersion of terminals and their commodity-specific nature often limit off-loading operations at certain terminals to their designated commercial purpose only. Other configurations could allow for the off-loading of additional commodities at these terminals. Consideration of alternative terminal uses during a sudden catastrophic closure requires a detailed understanding of terminal capabilities beyond historical commercial use. An investigation of alternative capabilities should be undertaken at each link in the interdependent inland marine and surface transportation systems to develop an effective decision-making framework.

Modeling the Impact of Inclement Weather on Freeway Traffic Speed at Macroscopic and Microscopic Levels

Inclement weather conditions, such as snowy and icy conditions, could have major impacts on driver behavior and on the performance of surface transportation systems. Recently, researchers have had an increased interest in understanding this impact better as well as in modeling it. This study contributes to the emerging literature in the impact of snowy and icy conditions on traffic and driver behavior by modeling the impact of inclement weather on freeway traffic speed, at both the macroscopic and microscopic levels, with data from Buffalo, New York. At the macroscopic level, freeway speed data observed on a Buffalo section of the New York State Thruway were correlated to a set of weather indices introduced by the study; the result was a regression model that could be used to estimate the average freeway speed as a function of weather conditions. At the microscopic level, the study was the first attempt to calibrate a cellular-automata traffic simulation model, specifically, the TRANSIMS model, to inclement weather (i.e., snowy) conditions. For the calibration of TRANSIMS, a vehicle equipped with a Global Positioning System collected second-by-second vehicle dynamics information during both normal and snowy weather conditions. The collected information was the basis for the adjustment of several of the TRANSIMS model parameters. The adjusted parameters enabled the model to closely replicate observed traffic flow parameters at both the macroscopic and microscopic scales.

On the Resilience of Ad Hoc Distributed Simulation of Surface Transportation Systems with Unreliable Communications

The Dynamic Data Driven Application Systems (DDDAS) concept is examined in the context of monitoring and managing surface transportation systems in day-to-day and emergency scenarios. An approach to predicting future system states termed ad hoc distributed simulations is described. This approach uses on-line distributed simulation models that can incorporate real-time data and utilizes rollback operations to update state predictions as new information becomes available. This paper focuses on examining the reliability of ad hoc distributed simulations in mobile computing environments, and specifically, assessing the accuracy of future state predictions in the face of unreliable communications.

Procurement of Sustainable Noise-Reducing Devices: State-of-the-Art Review from EU Project QUIESST

There is a pressing need for the sustainability of noise-reducing devices (NRDs) for transport systems to be considered by procurement agencies, policy makers, and industry professionals/designers in order to be in line with a growing sustainable agenda for surface transport systems including the supporting infrastructure. This need has been recognized by the European Union (EU) and an appropriate research project has recently been commissioned. Quietening the Environment for a Sustainable Surface Transport (QUIESST) is a three-year project funded by the EU that began late in 2009. It is a multidisciplinary project undertaken by 13 EU partners from eight countries. Within the project, the University of Bradford is the specialist research team tasked with assessing the sustainability of noise-reducing devices. These devices are designed to control noise from surface transport (both road and rail) and include noise barriers and absorptive claddings. For the purpose of this research, sustainability was defined as: the optimal consideration of technical, environmental, economical, and social factors during the design, construction, maintenance and repair, and removal/demolition stages of NRD projects. A comprehensive literature review has been carried out of the relevant European standards, design guides used around the world by road and rail authorities, and existing research on NRDs conducted by academics and leading practitioners to identify sustainable practices and gaps in the knowledge base. It became evident that sustainability factors are not being fully considered across the whole life cycle of NRDs. At the present time and based on the available data, it is not possible to quantify and rank NRDs in terms of sustainability for a given site, project, or case study. Clearly this has major implications for the management of the procurement process. Further data collection and analysis are required to provide guidance that can be considered useful for all stakeholders. This is the aim of the further stages of this work package within the QUIESST project. This paper presents an overview of the current state of the art for the sustainability of NRDs, and describes some of the major deficiencies while highlighting knowledge gaps and the further research that is needed.

Identifying Surface Transportation Vulnerabilities and Risk Assessment Opportunities under Climate Change

Transportation departments are beginning to recognize that adaptation for climate change must become an integral part of their planning efforts. However, staff members frequently lack the adequate local data, training, and guidance needed to begin adaptation planning assessments. As a result, planning for adapting to climate change has remained generally abstract and lacks the specificity needed to identify potential system vulnerabilities, assess risk, and prioritize responses. This report outlines a geographic information system–based method with which transportation departments can assess vulnerabilities to climate change in their multimodal surface transportation systems. The city of Portland, Oregon, is used as an illustrative case study. The proposed method allows for preliminary vulnerability identification, prioritization, and impact assessment and can also be used as a basis for more advanced analysis and scenario testing. This research also identifies and describes data gaps and other barriers to climate change adaptation planning for surface transportation.