Multiobjective Optimization for Hazardous Materials Transportation

2005 ◽  
Vol 1906 (1) ◽  
pp. 64-73 ◽  
Author(s):  
Bo Huang ◽  
Pierre Fery ◽  
Liangpei Zhang
Keyword(s):  
Hazardous Materials ◽  
Efficient Solutions ◽  
Geographical Information ◽  
Population Exposure ◽  
Hazardous Materials Transportation ◽  
Shortest Path Problems ◽  
Trade Offs ◽  
Conflicting Objectives

This research attempted to build a framework for determining optimal routes for hazardous materials transportation. Previous work has suggested the incorporation of many conflicting objectives in the analysis, such as travel cost, population exposure, environmental risk, and security concerns. Multiplying the number of objectives leads to complex shortest path problems that often have several efficient solutions. The present study emphasizes an overview of possible trade-offs among routes without generating all of them. A simple characterization of the efficient routes is used to select the best ones with no need for input from the decision maker. A case study with eight objective functions was performed on a road network in Singapore. A geographical information system was used to quantify road link attributes, which are assumed linear and deterministic for the sake of simplicity. The proposed algorithm derives four significantly different routes, which conform to intuition.

Tackling uncertainties in infrastructure sectors through strategic planning: the contribution of discursive approaches in the urban water sector

Water Policy ◽  
2010 ◽  
Vol 13 (3) ◽  
pp. 299-316 ◽  
Author(s):  
Damian Dominguez ◽  
Bernhard Truffer ◽  
Willi Gujer
Keyword(s):  
Strategic Planning ◽  
Planning Process ◽  
Qualitative Assessment ◽  
Urban Water ◽  
Strategic Decisions ◽  
Existing Structures ◽  
Conflicting Objectives ◽  
Planning Approaches

Several strategic planning approaches have been proposed for dealing with future uncertainties in the urban water infrastructure sector. We identify three well established perspectives that address uncertainties in strategic decisions: an adaptive perspective, focusing on an incremental adaptation of existing structures as a reaction to unforeseen developments, a modeling perspective, focusing on an improved characterization of future context conditions and a managerial perspective, focusing on increasing the flexibility of the infrastructure organization. Despite their virtues, these approaches have definite weaknesses in their approach to uncertainty: they often consider a restricted scope of alternatives, they face substantial difficulties in predicting context conditions over time periods of decades and often consider objectives and tradeoffs only implicitly. We elaborate and illustrate with a case study a fourth perspective that may compensate for these specific weaknesses and complement the established strategic planning approaches. This perspective is based on a discursive, qualitative assessment of key elements in the strategic planning process among a selected set of local stakeholders and decision makers. We maintain that this approach leads to a more explicit and reflexive treatment of future uncertainty, conflicting objectives and a broadening of the considered alternatives and therefore to a more robust decision-making process.

Minimax Population Exposure in Routing Highway Shipments of Hazardous Materials

1997 ◽  
Vol 1602 (1) ◽  
pp. 93-100 ◽  
Author(s):  
Erhan Erkut ◽  
Theodore Glickman
Keyword(s):  
United States ◽  
Nuclear Waste ◽  
Hazardous Materials ◽  
The United States ◽  
Population Exposure ◽  
Spent Fuel ◽  
Trade Offs ◽  
Total Travel Time ◽  
Multiple Routes ◽  
High Level

A routing model for hazardous materials with two objectives—to minimize maximum population exposure and to minimize total travel time—is introduced. The population exposure is quantified by the number of people in an impact circle of a selected radius. To solve this two-objective problem, the focus is placed on the second objective, with a constraint on the first objective. This results in a problem that is easy to solve and has a solution that is easy to interpret. To demonstrate the use of this model, a case of nuclear waste shipments (i.e., spent fuel) in the United States in considered. The model is applied, with two bounds on high-level population exposure, to 10 nuclear waste origins. The results of this application are reported. The model behaves in a predictable (and desirable) way, avoiding major population centers via detours. With its ability to quantify trade-offs between competing objectives, and its capacity to generate multiple routes for a shipment, the model has the potential to serve in a decision-support role for planning hazardous materials routes.

scholarly journals Risk Assessment of Hazmat Road Transportation Considering Environmental Risk under Time-Varying Conditions

2021 ◽  
Vol 18 (18) ◽  
pp. 9780
Author(s):  
Liping Liu ◽  
Qing Wu ◽  
Shuxia Li ◽  
Ying Li ◽  
Tijun Fan
Keyword(s):  
Risk Assessment ◽  
Environmental Pollution ◽  
Environmental Risk ◽  
Hazardous Materials ◽  
Assessment Model ◽  
Population Exposure ◽  
Model Parameters ◽  
Time Varying ◽  
Road Transportation ◽  
Hazardous Materials Transportation

Hazardous materials shipments are integral to the development of industrial countries. Significant casualties and severe environmental pollution quickly ensue when accidents occur. Currently, relevant research on risk assessment of hazardous materials’ road transportation remains limited when both the population exposure risk and environmental risk are considered, especially in regard to analyzing the differences of accident impacts in different populations and environments. This paper adopts a Gaussian plume model to simulate dynamic areas at three levels of population exposure and assesses the pollution scope of air, groundwater, lakes, and rivers with a variety of diffusion models. Then, we utilize various costs to analyze the differences of accident impacts in population exposure and environmental pollution. Finally, a risk assessment model of hazardous materials road transportation under time-varying conditions is presented by considering the bearing capacity of the assessed area. Furthermore, this model is applied to a case study involving a risk assessment of hazardous materials transportation of a highly populated metropolitan area of Shanghai, China. The resulting analyses reveal that the safety of hazardous materials transportation could be effectively improved by controlling certain model parameters and avoiding road segments with a high risk of catastrophic accident consequences.

scholarly journals A GIS-based framework for addressing conflicting objectives in the context of an ecosystem approach to fisheries management—a case study of the Portuguese sardine fishery

2018 ◽  
Vol 75 (6) ◽  
pp. 2070-2087 ◽  
Author(s):  
D Szalaj ◽  
L Wise ◽  
S Rodríguez-Climent ◽  
M M Angélico ◽  
V Marques ◽  
...  
Keyword(s):  
Fisheries Management ◽  
Fishery Management ◽  
Expert Knowledge ◽  
Ecosystem Approach ◽  
New Paradigm ◽  
Conservation Measures ◽  
Trade Offs ◽  
Spawning Areas ◽  
Conflicting Objectives

Abstract An ecosystem approach to fisheries management (EAFM) is as a new paradigm in fisheries management. In this study, a combination of geographic information systems (GISs) and multi-criteria decision-making method (MCDM) is proposed as a framework supporting an ecosystem approach to European sardine (Sardina pilchardus, Clupeidae) fishery management in Portugal. This case study was chosen due to the recent severe decline shown by the species. To develop an EAFM for the sardine fishery, a set of criteria were defined based on literature review and expert knowledge. To address multiple conflicting objectives, namely conservation and fisheries, five scenarios were considered: (i) baseline; (ii) nurseries protection; (iii) spawning areas protection; (iv) fishery profit driven, and (v) safeguarding dependent fishing communities. Combination of GIS and MCDM methods highlighted important areas to implement spatial conservation measures for sardine. The analyses indicate that some areas are suitable for conservation in several scenarios, such as the area near Aveiro and the area near the Tejo estuary. However, conservation measures implemented in the area near Aveiro would imply higher economic trade-offs when compared with the actions applied in the region near the Tejo estuary. Results also suggested some of the conservation objectives, such as the protection of sardine eggs and juveniles, to not be compatible. The proposed framework is an important tool supporting EAFM by addressing conflicting objectives, trade-offs and identifying areas that could be considered as potential fishery closure sites or subjected to further analyses.

A Path Based Algorithm for Solve the Hazardous Materials Transportation Bilevel Problem

2012 ◽  
Vol 253-255 ◽  
pp. 1082-1088
Author(s):  
José Fernando Camacho Vallejo ◽  
Rafael Muñoz Sánchez
Keyword(s):  
Mathematical Program ◽  
Transportation Network ◽  
Shortest Paths ◽  
Hazardous Materials ◽  
Upper Bounds ◽  
Government Agency ◽  
Population Exposure ◽  
Hazardous Materials Transportation ◽  
Total Cost ◽  
Upper Level

In this work we consider the problem of determining a set of optimal tolls on the arcs of a multicommodity transportation network. The problem is formulated as a bilevel mathematical program where the upper level consists in a government agency that regulate the traffic of the dangerous materials by imposing tolls on arcs of the network trying to minimize the risk for the population in the case when an accident occurs to the carriers, while the lower level is represented by a group of carriers traveling on shortest paths with respect to a generalized travel cost. So, the problem can be seen in a simplistic form as find the equilibrium between tolls that minimize the population exposure to the risk and tolls that are convenient for the shippers. The paper applies a path based algorithm to solve a bi-level multi-commodity optimal toll setting ‘hazmat’ problem. The algorithm consists in find upper bounds for the tolls considering the total cost and the risk associated to a particular path. We made several experiments and the results are shown in this work.

scholarly journals A Bi-Objective Fuzzy Credibilistic Chance-Constrained Programming Approach for the Hazardous Materials Road-Rail Multimodal Routing Problem under Uncertainty and Sustainability

2019 ◽  
Vol 11 (9) ◽  
pp. 2577 ◽  
Author(s):  
Yan Sun ◽  
Xinya Li ◽  
Xia Liang ◽  
Cevin Zhang
Keyword(s):  
Carbon Dioxide ◽  
Carbon Dioxide Emission ◽  
Hazardous Materials ◽  
Mixed Integer ◽  
Programming Approach ◽  
Population Exposure ◽  
Chance Constrained Programming ◽  
Routing Problem ◽  
Multimodal Transportation ◽  
Conflicting Objectives

Hazardous materials transportation involves extensive risk and cannot be avoided in practice. An advanced routing, however, can help to reduce the risk by planning the best transportation routes for hazardous materials that can make effective tradeoffs between the risk objective and the economic objective. In this study, we explore the hazardous materials routing problem in the road-rail multimodal transportation network with a hub-and-spoke structure, in which the risk is measured by the multiplication of population exposure and the associated volume of hazardous materials, and minimizing the total risk of all the transportation orders of hazardous materials is set as the risk objective. It is difficult to estimate the population exposure exactly during the routing decision-making process, which results in its uncertainty. In this study, we formulate the uncertain population exposure from a fuzzy programming perspective by using triangular fuzzy numbers. Moreover, the carbon dioxide emission constraint is formulated to realize the sustainable transportation of hazardous materials. To optimize the problem under the above framework, we first establish a bi-objective fuzzy mixed integer nonlinear programming model, and then develop a three-stage exact solution strategy that the combines fuzzy credibilistic chance constraint, linearization technique, and the normalized weighting method. Finally, a computational experiment is carried out to verify the feasibility of the proposed method in dealing with the problem. The experimental results indicate that tradeoffs between the two conflicting objectives can be effectively made by using the Pareto frontier to the hazardous materials routing problem. Furthermore, the credibility level and carbon dioxide emission cap significantly influence the hazardous materials routing optimization. Their effects on the optimization result are quantified by using sensitivity analysis, which can draw some useful insights to help decision makers to better organize the hazardous materials road-rail multimodal transportation under uncertainty and sustainability.

Construction of plastic contact deformation maps on ceramics: a case study on aluminum nitride

1996 ◽  
Vol 54 ◽  
pp. 636-637
Author(s):  
D. L. Callahan
Keyword(s):  
Plastic Deformation ◽  
Aluminum Nitride ◽  
Mechanical Response ◽  
Three Dimensional ◽  
Bright Field Image ◽  
Perfectly Plastic ◽  
Contrast Analysis ◽  
Deformation Patterns

Modern polishing, precision machining and microindentation techniques allow the processing and mechanical characterization of ceramics at nanometric scales and within entirely plastic deformation regimes. The mechanical response of most ceramics to such highly constrained contact is not predictable from macroscopic properties and the microstructural deformation patterns have proven difficult to characterize by the application of any individual technique. In this study, TEM techniques of contrast analysis and CBED are combined with stereographic analysis to construct a three-dimensional microstructure deformation map of the surface of a perfectly plastic microindentation on macroscopically brittle aluminum nitride.The bright field image in Figure 1 shows a lg Vickers microindentation contained within a single AlN grain far from any boundaries. High densities of dislocations are evident, particularly near facet edges but are not individually resolvable. The prominent bend contours also indicate the severity of plastic deformation. Figure 2 is a selected area diffraction pattern covering the entire indentation area.

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