2013 Session: 607

• Robust Dynamic Distribution of Security Assets in Transit Systems
  Abstract: A robust, mixed-integer, multi-stage program is presented that seeks to effectively secure a transit system where risk is considered to be dynamic and varies over time. A time-varying risk measure reflects the unique nature of transit systems, where accumulation of passengers at transfer facilities, stations and transit vehicles is dynamic and increases the vulnerability of the transit users and system to adverse events. The model is robust under uncertainty and better matches security assets at stations in the face of time-varying risk by redistributing them. The volume-dependent risk measure and subsequent deployment of security assets are developed for the transit system in Washington, D.C. demonstrating the variable nature of risk and response. The value of considering a robust solution is demonstrated by comparing the strategies developed from a robust approach to those from an expected value approach. Five scenarios, designed on recent events on the system, replicate the operational conditions of the transit system for the morning rush hour period and show the effectiveness of the developed deployment strategies.
  Authors: Nair, Rahul; Kumi, Jonathan; Denny, Kevin; Miller-Hooks, Elise
  Authors: Nair, Rahul; Kumi, Jonathan; Denny, Kevin; Miller-Hooks, Elise
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors; Security and Emergencies
  Session: 607
  Paper Number: 13-1641
• Investigation of Existing Nonintrusive Inspection Technologies for Port Cargo Inspections by Discrete-Event Simulation Modeling
  Abstract: The quantity of cargo handled by United States ports has increased significantly in recent years. Based on 2004 data, almost 2.7 billion tons of cargo passed through the ports in one year. To protect the U.S., all of this cargo must be inspected by U.S. Customs Border Protection (CBP) officials in the most effective manner possible. Existing non-intrusive inspection (NII) technologies have significant strengths, but they also have some weaknesses, such as a low detection rate and a long inspection time. Fortunately, there are newer and more advanced technologies that can be used to inspect cargo with higher accuracy and less delay. The goal of this research was to identify the most effective and efficient combination of NII technologies for inspecting cargo arriving at U.S. ports. For this purpose, a discrete-event simulation model was developed to simulate the cargo inspection procedure. By simulating the operations of different combinations of NII technologies, the effectiveness and efficiency of the various combinations were evaluated. This information was used to provide recommendations about the most effective and efficient combinations of NII technologies for detecting a wide range of contraband. The results of this research are helpful in making decisions concerning the appropriate choices of NII technologies for use in inspecting cargo that is entering U.S. ports.
  Authors: Qi, Yi; Salehi, Yasamin; Wang, Yubian
  Authors: Qi, Yi; Salehi, Yasamin; Wang, Yubian
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors; Security and Emergencies
  Session: 607
  Paper Number: 13-2083
• Using National Household Travel Survey Data for Assessment of Transportation System Vulnerabilities
  Abstract: This paper describes how the National Household Travel Survey (NHTS) data can be used within the framework of FEMA’s recently promulgated THIRA (Threat Hazard Identification Risk Assessment) approach to assess transportation system vulnerability. Following this five step process for identifying and assessing risks and associated impacts, the purpose of this paper is three-fold. First, the intent of the paper is to find common ground between the Department of Homeland Security, Federal Emergency Management Agency, and the Department of Transportation systems, approaches, and methods of risk assessment. Second, the paper looks specifically at transportation vulnerabilities. Vulnerability has been traditionally associated with the loss of the transportation infrastructure assets or the loss of efficacy of the transportation system. This approach is expanded and improved by shifting the focus of transportation system infrastructure to the travel patterns and attributes of the individuals. Third, using data from Honolulu, the largest county in Hawaii, the vulnerability of transportation assets is evaluated. The findings are useful not just for Hawaii, but the methodological contributions are relevant to broader concerns regarding risk, risk assessment, threat and hazard reduction. The paper first describes how the proposed approach of transportation system vulnerability assessment fits within the THIRA process. A transportation system vulnerability assessment method is then developed and demonstrated using data from the 2001 NHTS Oahu add-on survey and probable coastal inundation scenario caused by hurricane storm surge, inland flooding and sea level rise. A GIS-based approach was used for simulation of travel routes and to assess the transportation system vulnerabilities for individuals and households. In addition to demonstrating the importance and value of NHTS data, recommendations for improving the quality, availability, and usefulness of this important data source for the reduction of risks are provided
  Authors: Kim, Karl; Pant, Pradip; Yamashita, Eric Yukio
  Authors: Kim, Karl; Pant, Pradip; Yamashita, Eric Yukio
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors; Security and Emergencies
  Session: 607
  Paper Number: 13-2527
• Criticality Prioritization of Transportation Infrastructure Under Flooding in Coastal Areas
  Abstract: Climate change is challenging human society with frequent and serious impacts. Transportation infrastructures in the coastal area are especially vulnerable to flood impacts from storm surge, sea level rise, intense precipitation, and so on. Transportation infrastructure maintenance and retrofit plan should give priority to critical infrastructures whose failure will have important impacts on the network performance. In order to better inform decision makers of the criticality of transportation infrastructures in case of flooding, this study explores an accessibility-based criticality prioritization methodology to identify and rank critical transportation infrastructures under flooding risks. In particular, the methodology evaluates the network-wide impacts of infrastructure failure based on the increase in travel cost taking traffic congestion, trip cancellation, and location importance into account. The methodology is applied to the road network of Hillsborough County, Florida. Light detection and ranging elevation data, transportation infrastructure and network, and zone-based population data of the County are processed for the analysis. The approach yields results of not only the criticality prioritization of transportation infrastructures at flooding risks but also the most vulnerable regions as a result of infrastructure inundation. We show that some infrastructures are critical to its surrounding areas, while some become important to a much broader region. The results further demonstrate that an infrastructure is more critical if it serves more people in the study area.
  Authors: Lu, Qing-Chang; Peng, Zhong-Ren; Zhang, Junyi
  Authors: Lu, Qing-Chang; Peng, Zhong-Ren; Zhang, Junyi
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors; Security and Emergencies
  Session: 607
  Paper Number: 13-3199
• Computational Method for Calculation of Blast Pressure Outside Vented Suppressive Shield Containers
  Abstract: Vented Suppressive shield (VSS) containers have traditionally been used for storage of hazardous materials, especially explosives, and to attenuate the blast effects (pressure and impulse) as well as eliminate primary fragment hazard associated with accidental explosions. Most VSS containers are designed from experience and observation from container test programs. This design process, however, limits the designer’s ability to economize on materials or use suppressive shield configurations other than those used in the test programs. The aim of this study is to investigate the interaction between the blast waves and the structural steel elements used in VSS. This paper investigates the effect of different VSS sections (configurations) in attenuating blast pressure outside the container and to develop semi-empirical equations that can be used to predict blast pressure and impulse outside VSS containers. AUTODYN® - a commercial software package was used to model the explosive detonation process and evolution of blast wave and its interaction with the VSS. Different VSS configurations ranging in complexity and consisting of single and multilayer VSS shields were studied. The single and multilayer VSS shields were compared and used to develop semi-empirical equations to predict the pressure and impulse outside the VSS container. The proposed equations were compared with experimental results obtained from previous experimental test program and showed very good correlation.
  Authors: Abdelalim, Omar; Braimah, Abass; Abd El Halim, Halim Omar
  Authors: Abdelalim, Omar; Braimah, Abass; Abd El Halim, Halim Omar
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors; Security and Emergencies
  Session: 607
  Paper Number: 13-3930
• Spatial Criticality of Transportation Risks from Sea Level Rise, Storm Surge, and Tsunami Hazards in Honolulu, Hawaii
  Abstract: n this paper, the potential effects of sea level rise, coastal storms, flooding and tsunami hazards on communities and transportation assets in Hawaii are described. Beginning with a description of the different hazards and the estimated return periods, the hazard areas are delineated and mapped. Then, three different dimensions of vulnerability are analyzed. The first relates to population characteristics, the second is focused on critical infrastructure, and the third addresses transportation system capabilities and usage. A scoring system for assessing the criticality of these different dimensions of vulnerability is devised and implemented using a uniform grid based geography. In addition to comparing the three different dimensions of vulnerability, an overall aggregate score for each grid cell in the affected area is derived. This allows for the determination of an overall criticality score based on the three different dimensions. In this analysis, the three different dimensions are equally weighted. Using various proposed approaches, weights and sub-weights for each of the dimensions could be derived based on the preferences and values of community members, elected or appointed officials and or emergency managers. Moreover, as data on hazards and vulnerabilities become available, the vulnerability of locations and their supporting transportation infrastructure can be adjusted. Then locations can be readily identified by the existence of routine and extensive flooding, identifiable natural processes such as streams, wetlands, natural areas suitable for buffering and water retention, and key opportunities for sustainable, green development. Criticality can be seen both in terms of the short term reduction of threats and risks as well as in terms of longer term redevelopment and transformation of vulnerable areas.
  Authors: Kim, Karl; Pant, Pradip; Yamashita, Eric Yukio; Ghimire, Jiwnath; Brunner, I Made Indradjaja
  Authors: Kim, Karl; Pant, Pradip; Yamashita, Eric Yukio; Ghimire, Jiwnath; Brunner, I Made Indradjaja
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors; Security and Emergencies
  Session: 607
  Paper Number: 13-4864
• Criticality Prioritization of Transportation Infrastructure Under Flooding in Coastal Areas
  Authors: Lu, Qing-Chang
  Authors: Lu, Qing-Chang
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors; Security and Emergencies
  Session: 607
  Paper Number: 13-3199
• Spatial Criticality of Transportation Risks from Sea Level Rise, Storm Surge, and Tsunami Hazards in Honolulu, Hawaii
  Authors: Kim, Karl
  Authors: Kim, Karl
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors; Security and Emergencies
  Session: 607
  Paper Number: 13-4864
• Using National Household Travel Survey Data for Assessment of Transportation System Vulnerabilities
  Authors: Kim, Karl
  Authors: Kim, Karl
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors; Security and Emergencies
  Session: 607
  Paper Number: 13-2527