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During our modern era, there are various types and numbers of chemically dangerous objects in the territory of our Republic, and they are constantly in operation. Thus, during the operation of these objects, significant reserves of dangerous chemicals of an emergency nature are used in a certain amount. According to information, thousands of tons of hazardous chemical substances are transported from one area to another in the Republic of Azerbaijan every year. So, the vehicles carrying those types of chemically dangerous substances have to pass through areas inhabited by people. Also, in case of accidents during the transportation, there may be a large number of people in the chemical contamination zone. As we know, as a result of the spillage of dangerous chemicals, the environment, living beings, people, and animals are damaged in a huge amount. In order to prevent this, a plan of various measures should be implemented. In this article, special parameters were mainly used in the study of the dispersion of dangerous chemicals as a result of an accident and risk assessment, which are used for the main work: 1. Toxodose of dangerous chemicals according to distance and effect. 2. The average concentration of dangerous chemical substances entering the human body by inhalation. 3. Site of accidental spillage of chemical hazardous substances. 4. Area coefficient of distribution of known types of hazardous chemicals. 5. Infiltration [ABSTRACT FROM AUTHOR]

With the increase of hazardous materials (Hazmat) demand and transportation, frequent Hazmat road transportation accidents had arisen the widespread concern in the community. Thus, it is necessary to analyze the risk factors’ implications, which would make the safety of Hazmat transportation evolve from “passive type” to “active type”. In order to explore the influence of risk factors resulting in accidents and predict the occurrence of accidents under the combination of risk factors, 839 accidents that have occurred for the period 2015–2016 were collected and examined. The Bayesian network structure was established by experts’ knowledge using Dempster-Shafer evidence theory. Parameter learning was conducted by the Expectation-Maximization (EM) algorithm in Genie 2.0. The two main results could be likely to obtain the following. (1) The Bayesian network model can explore the most probable factor or combination leading to the accident, which calculated the posterior probability of each risk factor. For example, the importance of three or more vehicles in an accident leading to the severe accident is higher than less vehicles, and in the absence of other evidences, the most probable reasons for “explosion accident” are vehicles carrying flammable liquids, larger quantity Hazmat, vehicle failure, and transporting in autumn. (2) The model can predict the occurrence of accident by setting the influence degrees of specific factor. Such that the probability of rear-end accidents caused by “speeding” is 0.42, and the probability could reach up to 0.97 when the driver is speeding at the low-class roads. Moreover, the complex logical relationship in Hazmat road transportation accidents could be obtained, and the uncertain relation among various risk factors could be expressed. These findings could provide theoretical support for transportation corporations and government department on taking effective measures to reduce the risk of Hazmat road transportation. [ABSTRACT FROM AUTHOR]

Route optimization of hazardous materials transportation is one of the basic steps in ensuring the safety of hazardous materials transportation. The optimization scheme may be a security risk if road screening is not completed before the distribution route is optimized. For road screening issues of hazardous materials transportation, a road screening algorithm of hazardous materials transportation is built based on genetic algorithm and Levenberg–Marquardt neural network (GA-LM-NN) by analyzing 15 attributes data of each road network section. A multi-objective robust optimization model with adjustable robustness is constructed for the hazardous materials transportation problem of single distribution center to minimize transportation risk and time. A multi-objective genetic algorithm is designed to solve the problem according to the characteristics of the model. The algorithm uses an improved strategy to complete the selection operation, applies partial matching cross shift and single ortho swap methods to complete the crossover and mutation operation, and employs an exclusive method to construct Pareto optimal solutions. Studies show that the sets of hazardous materials transportation road can be found quickly through the proposed road screening algorithm based on GA-LM-NN, whereas the distribution route Pareto solutions with different levels of robustness can be found rapidly through the proposed multi-objective robust optimization model and algorithm. [ABSTRACT FROM AUTHOR]

Discusses the possibility of the occurrence of tunnel fire in the transportation of spent nuclear waste to a repository at Yucca Mountain, Nevada through railways. Information on a fire tunnel in Baltimore, Maryland on July 18, 2001 that involved a train with hazardous materials; Hypothetical consequences of a Baltimore-like accident that involves spent nuclear fuel; Routes being considered for the transportation of spent nuclear fuel to Yucca Mountain.

Transportation of dangerous goods (DGs) is generally associated with significant levels of risk. In the context of DG transportation, risk refers to the likelihood of incurring the undesirable consequences of a possible accident. Since the probability of an accident in a link of a route might depend on a variety of factors, it is necessary to find a way to combine the pieces of evidence/probabilities to estimate the composite probability for the link. Instead of using the Bayesian approach, commonly used in the literature, which requires decision-makers to estimate prior and conditional probabilities and cannot differentiate uncertainty from ignorance, this paper presents a novel approach based on the extended Dempster-Shafer theory of evidence by constructing an adaptive robust combination rule to estimate the accident probability under conflicting evidence. A case study is carried out for the transportation of liquefied petroleum gas in the road network of Hong Kong. Experimental results demonstrate the efficacy of the proposed approach. [ABSTRACT FROM AUTHOR]

Transportation has a great role in logistics. Many researchers have studied on transportation and vehicle routing problems. Transportation of hazardous materials (hazmat) is a special subject for logistics. Causalities due to the accidents caused by trucks carrying hazardous materials will be intolerable. Many researchers have studied on risk assessment of hazmat transportation to find ways for reducing hazardous material transportation risks. Some researchers have studied routing of hazmat trucks. The emergency response models and network design problems for hazmat transportation were also studied by some researchers. The transportation of hazmats can also be classified according to the mode of transport. Mainly roads are used for hazmat transportation but some shipments are intermodal. There has been a great amount of effort spent to find convenient ways for hazmat transportation. In this study, a literature survey for the articles about hazmat transportation is prepared. After pointing out the importance of hazmat transportation by the example of US hazmat transportation data, the studies on hazmat transportation since 2005 have been examined. Totally 88 articles are classified as risk, routing, routing and scheduling, emergency response, network design and accident analysis. What can be studied in future researches is pointed out. [ABSTRACT FROM AUTHOR]

In the Serbian Armed Forces, oil and petroleum products are transported primarily for military units and institutions. The route for the movement of vehicles is selected during the transportation planning process. This paper describes a methodology for the selection of a route for the transport of dangerous goods and its application on one particular case in the Serbian Armed Forces. [ABSTRACT FROM AUTHOR]

This article describes a project sponsored by the Hazardous Materials Cooperative Research Program to determine the most promising emerging technologies for the safety and security of hazardous materials (hazmat) shipments. The project's focus was on hazmat transportation of all modes (i.e., highway, rail, marine, air, and pipeline). A requirements-based gap analysis methodology was utilized to screen and down-select an initially large number of potential candidate technologies. The methodology resulted in the identification of most promising emerging technology areas for further examination. Each of these technology areas was further characterized in terms of its applicability to hazmat transportation safety and security and its outlook for deployment. In addition to describing project activities and findings, the article offers a commentary on overarching considerations influencing the development and deployment of technologies with the potential to enhance hazmat transportation safety and security within the coming decade. [ABSTRACT FROM AUTHOR]

Transport route optimization of dangerous goods makes lower transportation risk and cost of the enterprise, meanwhile it provides basis reference for the government decision. On the basis of urban master planning, the characteristics of transport of dangerous goods was analyzed, and then the index system on transport of dangerous goods was established. In order to implement this research and quantify the indicators, road characteristics and nature of land along the section has been used to evaluate the risk, simultaneously, the emergency response capacity was considered as the correction factor to improve the risk model, and the BPR impedance function was applied to calculate the transportation costs, then the calculation process of transportation risk and costs was given with an example of Pingxiang, Jiangxi. On this basis, a bi-objective optimization model was created with the target of risk and cost, and method of solving the model was discussed. This model provides a theoretical basis for the transport network of dangerous goods planning and design for its simplicity, practicality and operability. [ABSTRACT FROM AUTHOR]

Transport of dangerous goods are regulated activities, they take place under the direction and control of the authorities and specialized bodies in an institutional framework determined by national and international law. Of economic, transport infrastructure is the crucial element without which both production and trade would become meaningless, it is an essential element of a civilization, is also a necessary accessory of other economic activities [ABSTRACT FROM AUTHOR]

Abstract: Often, the carrier/shipper of hazardous materials is interested in a collection of routes with approximately the same performance so that they can switch between different routes to avoid exposing the same population and potentially as a security measure. We develop a K shortest path algorithm for which the performance of each highway facility, with respect to each objective, can be stochastic and can vary over time. We also devise a mixed integer program to identify a subset of paths, which represents an acceptable trade-off between geographic diversity and performance. These models are then applied to a realistic case study. [Copyright &y& Elsevier]

This article describes a methodology to model the degree of remedial action required to make short stretches of a roadway suitable for dangerous goods transport (DGT), particularly pollutant substances, using different variables associated with the characteristics of each segment. Thirty-one factors determining the impact of an accident on a particular stretch of road were identified and subdivided into two major groups: accident probability factors and accident severity factors. Given the number of factors determining the state of a particular road segment, the only viable statistical methods for implementing the model were machine learning techniques, such as multilayer perceptron networks (MLPs), classification trees (CARTs) and support vector machines (SVMs). The results produced by these techniques on a test sample were more favourable than those produced by traditional discriminant analysis, irrespective of whether dimensionality reduction techniques were applied. The best results were obtained using SVMs specifically adapted to ordinal data. This technique takes advantage of the ordinal information contained in the data without penalising the computational load. Furthermore, the technique permits the estimation of the utility function that is latent in expert knowledge. [Copyright &y& Elsevier]

The article presents abstracts on transportation topics including bulk shipping and freight weights, hazardous material transportation, and express shipping services.

Dangerous-goods shipments remain regulated despite the widespread deregulation of the transportation industry. This is mainly due to the societal and environmental risks associated with these shipments. One of the common tools used by governments in mitigating transport risk is to close certain roads to vehicles carrying hazardous materials. In effect, the road network available to dangerous goods carriers can be determined by the government. The associated transport risk, however, is determined by the carriers' route choices. We provide a bilevel programming formulation for this network design problem. Our approach is unique in terms of its focus on the nature of the relationship between the regulator and carriers. We present an application of our methodology in Western Ontario, Canada. [ABSTRACT FROM AUTHOR]

The engineering concepts necessary for fully describing contaminant transport processes in soil and groundwater have been largely neglected by traditional civil engineering curricula in the United States. New lecture and laboratory modules have been developed and integrated into the undergraduate soil mechanics course for civil engineering students at the Colorado School of Mines. The lecture module includes theoretical development of the advection-dispersion equation and a set of practical example problems designed to clarify the relative importance of advection, dispersion, and molecular diffusion in realistic contaminant transport scenarios. The laboratory experiment is developed using relatively inexpensive soil permeability testing equipment common to most academic and industrial geotechnical engineering laboratories. Unlike conventional chemical transport testing, which requires relatively complicated, time consuming, and expensive analytical instrumentation, the new laboratory exercise relies on the use of simple colored dye for simulating the movement of a contaminant through a one-dimensional soil column. The key soil parameters governing the transport of the dye, including the diffusion coefficient, hydraulic conductivity, dispersion coefficient, and retardation coefficient, are quantified by observing the location and color intensity of the dye as it moves through the column. Emphasis is placed on maximizing the simplicity and visual impact of the experimental exercise. The effectiveness of the lecture and laboratory modules is assessed through a student survey. [ABSTRACT FROM AUTHOR]

This article presents a methodology for assessment of the hazardous materials transport risk in a multicommodity, multiple origin – destination setting. The proposed risk assessment methodology was integrated with a Geographical Information System (GIS), which made large-scale implementation possible. A GIS-based model of the truck shipments of dangerous goods via the highway network of Quebec and Ontario was developed. Based on the origin and destination of each shipment, the risk associated with the routes that minimize (1) the transport distance, (2) the population exposure, (3) the expected number of people to be evacuated in case of an incident, and (4) the probability of an incident during transportation was evaluated. Using these assessments, a government agency can estimate the impact of alternative policies that could alter the carriers’ route choices. A related issue is the spatial distribution of transport risk, because an unfair distribution is likely to cause public concern. Thus, an analysis of transport risk equity in the provinces of Quebec and Ontario is also provided. [ABSTRACT FROM AUTHOR]

We consider the strategic level routing problem of hazardous materials in marine waters over a multicommodity network with multiple origins-destinations. The problem is motivated by the fact that selecting optimal routes by each origin-destination pair or by each type of material is myopic and may result in overloading certain links of the transportation network and, consequently, in poor overall system performance. We employ a network flow model, instead of the traditional shortest path formulation, to capture the multicommodity, multiple origin-destination nature of the problem. An efficient two-phase solution approach is proposed. The proposed solution methodology is illustrated through a single hazmat problem followed by a large scale case study of the marine transportation system of oil products in the Gulf of Mexico. [ABSTRACT FROM AUTHOR]

This paper derives six objectives for routing hazardous material by viewing shipments as a sequence of independent Bernoulli trials. An example that compares these objectives is presented. Suitable approximations toward the use of these objectives in an optimization framework are provided. The paper also discusses the objectives from the viewpoint of their use to make actual hazardous material routing decisions. [ABSTRACT FROM AUTHOR]

In this paper, we consider the problem of determining a path that maximizes a multi-attribute, non-order-preserving value function. The motivating application is the determination of a most preferred path for transporting hazardous materials based on transportation cost and risk to population. A sub-path of an optimal path may not be optimal for a non-order-preserving value function, implying that a traditional application of dynamic programming may intentionally or unintentionally produce sub-optimal paths. We consider two approximation procedures for two general cases, the q = 0 case and the q > 0 case, where q is the number of required intermediate stops between origin and destination. The first approximation procedure involves applying dynamic programming as if a sub-path of an optimal path were always optimal. The second approximation procedure involves determining a linear order-preserving criterion that approximates the non-order-preserving value function and then applying dynamic programming. We use the best-first search algorithm BU* to determine optimal routes for both the q = 0 and q > 0 cases. We examine the frequency and magnitude of the resulting sub-optimalities for a multi-attribute value model based on a six-county road network that includes Cleveland, Ohio. Numerical results show that if one of the two approximations is used, significant sub-optimalities can occur over a wide range of decision maker preferences. Both approximations can produce sub-optimality error magnitudes of over 50%. [ABSTRACT FROM AUTHOR]

This paper is concerned with the development and analysis of a mathematical model for determining a route that attempts to reduce the risk of low probability-high consequence accidents related with the transportation of hazardous materials. The approach adopted considers trade-offs between the conditional expectation of a catastrophic outcome given that an accident has occurred, and more traditional measures of risk dealing with the expected value of the consequence and the accident probability on a selected path. More specifically, the problem we address involves finding a path that minimizes the conditional expectation objective value, subject to the expected value of the consequence being lesser than or equal to a specified value v, and the probability of an accident on the path being also constrained to be no more than some value η. The values v and η are user-prescribed and could be prompted by the solution to the shortest path problems that minimize the respective corresponding linear risk functions. The proposed model is a discrete, fractional programming problem that is solved using a specialized branch-and-bound approach. A numerical example is provided for the sake of illustration, and some computational experience on randomly generated test cases is provided to study the effort required to solve this problem in different instances. The model is also tested using realistic data associated with a case concerned with routing hazardous materials through the roadways of Bethlehem, Pennsylvania. Data acquisition as well as algorithmic computational issues are discussed. [ABSTRACT FROM AUTHOR]

The economic loss associated with the involvement of a hazardous materials truck in an accident can be very high. Although the immediate costs are usually borne by an insurer, the carrier would incur an increase in its future insurance costs as a result. Thus, a hazardous materials carrier can benefit from considering its long-term insurance costs in routing the required shipments. In this paper, we introduce the hazardous materials routing problem under insurance costs. We present a solution methodology that facilitates evaluation of alternative routing policies. The proposed methodology involves solution of a manageable number of shortest path problems in determining the most appropriate route(s). We argue that, for each shipment, the route to be taken by the truck should be determined on the basis of the expected increase in insurance costs due to a possible accident as well as the cost of transportation. [ABSTRACT FROM AUTHOR]

This paper considers integrated location and routing models for minimizing the expected number of hazardous material transport accidents. Two different routing policies are considered: (1) most reliable route planning and (2) multiple routing with random selection. Path reliability measurements are used to derive the expected number of accidents over a given planning horizon, where reliability refers to the probability of completing a journey without accident. Corresponding to the two routing policies, two location models are introduced: the reliable 1-median and a location framework for considering multiple routes. Based on realistic assumptions for assigning accident probabilities to segments created when an edge location is considered, vertex optimality results for both problems are obtained. An example to illustrate reliable routing and location in Massachusetts is provided. [ABSTRACT FROM AUTHOR]

Recognition of time-varying patterns of accident rates and exposure parameters can be used to improve routing and scheduling decisions for hazardous materials shipments. An integrated routing/scheduling approach can be used to reduce overall risk, and find preferred solutions in a multiobjective context. We describe a method for performing an integrated routing/scheduling analysis, and illustrate its use in a case study. We also construct estimates of the "value of information" for incorporation of this time-dependent data. [ABSTRACT FROM AUTHOR]

Commercially available tracking systems based on advanced communications and computing technology allow a dispatcher of hazardous material transports to monitor the movement of vehicles on a transportation network in real time. When unexpected events occur, a dispatcher working with this new technology can identify the regions surrounding the transportation network that are affected by these events and determine safe and cost-effective routes for the vehicles that plan to drive through those regions. Four decision models for rerouting hazardous material vehicles in real-time have been assessed in an experimental setting. The first model supports a dispatcher in finding alternative routes (visually), while the second model adds to the display, for each vehicle, an alternative route based on a conservative heuristic. The other two models are based on an ordinal preference and a numerical utility structure to support the dispatcher in determining the impact of the events on transportation safety and costs. The models were embedded into four decision support systems that use multimedia technology to simulate the dispatchers workstations. These systems were then used in an experiment at the dispatching school in Wil, Switzerland, with 32 experienced dispatchers and truck drivers to assess efficiency and accuracy of the four models. The results show that assessing risks and costs with the ordinal preference structure, prior to making routing decisions, is significantly more efficient and accurate than searching directly for new routes. Using a numerical scale for safety and cost assessment was disliked by the subjects and led to inferior results. [ABSTRACT FROM AUTHOR]

This paper considers two new decision-making problems in the context of transporting hazardous materials (HM). These problems are motivated by the fact that many practical situations only have a finite number of shipments of HM to be made and that shipments are likely to be suspended after a threshold number of accidents. Both problems are nonlinear, constrained shortest path problems. Exact solution methods are proposed and computational results are reported for the case where the threshold number of accidents is one. Extension of the methodology for higher values of the threshold number of accidents is also outlined. [ABSTRACT FROM AUTHOR]

This paper considers the problem of determining optimal paths for routing an undesirable vehicle on a network embedded on an Euclidean plane. A typical application is the transporting of hazardous materials. Demand points, or population centers, are discretely distributed at nodes and continuously distributed on straight-line links of the network. The objective is to find, without incorporating the probability of accidental leakage of hazardous material, a path that minimizes the weighted sum of lengths over which this vehicle is within a threshold distance lambda of population centers. By appropriately redefining link lengths, we can use a shortest-path algorithm to solve the problem. Special properties of the objective function allow us to efficiently calculate the modified link lengths. We discuss the properties of the optimal routing strategy and the objective value, and offer an economic interpretation of the case when lambda varies. Operating within the framework of risk analysis, we integrate the probability of accidental release of hazardous material into our basic model. The routing objective becomes the minimization of expected damage, where accidental leakage of hazardous materials can inflict damage within a neighborhood lambda of the accident site. We also discuss our computational experience in using the model. [ABSTRACT FROM AUTHOR]

The article presents information about the contents of the August 1997 issue of the journal "Transportation Science." According to the author, the goal of this focused issue is to present the readers of "Transportation Science" with a collection of papers representing the state-of-the-art in this area as it is seen from an operations research perspective. In his opinion, problems in this area are multiple objective complicated due to many factors: models are data-hungry, the underlying problems are of a combinatorial nature, accounting for risks is not a straightforward matter, and there are multiple objectives. According to the author, the article "Location and Reliable Routing of Hazmats," published in this issue considers integrated location and routing models for minimizing the expected number of hazmat transport accidents. Two different routing policies are considered: most reliable route planning, and multiple routing with random selection. Path reliability measurements are used to derive the expected number of accidents over a given planning horizon, where reliability refers to the probability of completing a journey without accident.