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Transportation Safety Performance Of Us Bus Transit Agencies And Population Density: A Cross-Sectional Analysis (2008-2014), Ilker Karaca, Peter T. Savolainen Jul 2019

Transportation Safety Performance Of Us Bus Transit Agencies And Population Density: A Cross-Sectional Analysis (2008-2014), Ilker Karaca, Peter T. Savolainen

Ilker Karaca

The paper examines the transportation safety performance of transit agencies providing public bus service in the US by using data from the National Transit Database (NTD)

Uses NTD data for a seven-year period from 2008 to 2014 • 3,853 observations for 651 public transportation agencies in 50 states

Seven types of bus transit fatalities and injuries (including passengers, operators, pedestrians, bicyclists)

Main explanatory variable: urban density obtained from the US Census figures

Other explanatory variables: total agency revenue miles, unlinked passenger trips, agency fleet size, and urban population


Nchrp Synthesis 499: Alternate Design/Alternate Bid Process For Pavement-Type Selection. A Synthesis Of Highway Practice, Douglas D. Gransberg, Ashley F. Buss, Ilker Karaca, Michael C. Loulakis Jul 2019

Nchrp Synthesis 499: Alternate Design/Alternate Bid Process For Pavement-Type Selection. A Synthesis Of Highway Practice, Douglas D. Gransberg, Ashley F. Buss, Ilker Karaca, Michael C. Loulakis

Ilker Karaca

Highway administrators, engineers, and researchers often face problems for which information already exists, either in documented form or as undocumented experience and practice. This information may be fragmented, scattered, and unevaluated. As a consequence, full knowledge of what has been learned about a problem may not be brought to bear on its solution. Costly research findings may go unused, valuable experience may be overlooked, and due consideration may not be given to recommended practices for solving or alleviating the problem. There is information on nearly every subject of concern to highway administrators and engineers. Much of it derives from research …


Top-Down Construction Cost Estimating Model Using An Artificial Neural Network, Douglas D. Gransberg, H. David Jeong, Ilker Karaca, Brendon Gardner Jun 2019

Top-Down Construction Cost Estimating Model Using An Artificial Neural Network, Douglas D. Gransberg, H. David Jeong, Ilker Karaca, Brendon Gardner

Ilker Karaca

This report contains the information and background on top-down cost estimating using artificial neural networks (ANN)_to enhance the accuracy of MDT early estimates of construction costs. Upon conducting an extensive review of MDT’s budgeting and cost estimating efforts, and following a survey of agency experts on the identification of the most salient project attributes with the dual-objectives of low effort and high accuracy, a rational method for top-down variable selection is proposed. Selected variables were further tested in their explanatory power of construction costs through the application of two cost estimating methodologies—multiple regression and artificial neural network methodologies. Both methods …


Not-So-Risky Business? Assessing The Risk Of Integrating Large Rpvs Into The Current Air Traffic System, Hans-Joachim K. Ruff-Stahl, Steven Esser, Dirk Farsch, Thomas Graner, Robert Klein, Christian Schneidt, Stefan Schoenborn Jul 2018

Not-So-Risky Business? Assessing The Risk Of Integrating Large Rpvs Into The Current Air Traffic System, Hans-Joachim K. Ruff-Stahl, Steven Esser, Dirk Farsch, Thomas Graner, Robert Klein, Christian Schneidt, Stefan Schoenborn

Hans-Joachim Ruff-Stahl

In spite of considerable efforts to commercialize large remotely piloted vehicles (RPV), an integration of these RPVs into the existing Air Transportation System (ATS) and Airspace Structure is pending. The purpose of this paper was to assess the risks of an exemplary integration of a Heron 1 type RPV into the existing European air space structure within the current regulatory framework and without the availability of sense and avoid technology. Six incident occurrence scenarios were investigated, based on a modified Fault Tree Analysis and Eurocontrol’s risk matrix. It was found that without the implementation of technological or procedural changes, an …


High Consequence Scenarios For North Korean Atmospheric Nuclear Tests With Policy Recommendations For The U.S. Government, Thomas S. Popik, Jordan T. Kearns, George H. Baker Iii, Henry F. Cooper, William R. Harris May 2018

High Consequence Scenarios For North Korean Atmospheric Nuclear Tests With Policy Recommendations For The U.S. Government, Thomas S. Popik, Jordan T. Kearns, George H. Baker Iii, Henry F. Cooper, William R. Harris

George H Baker

The government of North Korea has declared high-altitude EMP-capability to be a “strategic goal” and has also threatened an atmospheric test of a hydrogen bomb. Atmospheric nuclear tests have the potential to cripple satellites and the undersea cable networks critical to communication, and navigation necessary for trans-Pacific trade among the U.S., China, and other nations. When a nuclear warhead is detonated at high altitude, a series of electromagnetic pulses radiate downward within the line of sight of the blast. These pulses can disable equipment with miniature electronics and long conductors. Electric grid controls and transmission systems are especially vulnerable. Intense …


Hispanic Maternal And Children's Perceptions Of Neighborhood Safety Related To Walking And Cycling, Norma Olvera, Dennis W. Smith, Chanam Lee, Jian Liu, Jay Lee, Stephanie Kellam, Jun-Hyun Kim Sep 2017

Hispanic Maternal And Children's Perceptions Of Neighborhood Safety Related To Walking And Cycling, Norma Olvera, Dennis W. Smith, Chanam Lee, Jian Liu, Jay Lee, Stephanie Kellam, Jun-Hyun Kim

Jian Liu

This study examined neighborhood safety as perceived by children (mean age=10 years) and their mothers, and its association with children's physical activity. For all eight safety items examined, children perceived their environment as less dangerous than mothers (p<0.05). None of the multiple regression models predicting children's physical activity by safety perceptions were significant (p>0.10). The maternal perception model explained the highest percentage of variance (R2=0.26), compared to the children's perception model (R2=0.22). Findings suggest that future studies should explore relations between self-reported and objectively measured safety barriers to Hispanic youth walking and cycling.


A Review Focujsed On The Psychological Effectiveness Of Tai Chi On Different Populations, Long Zhang, Thomas Lowder, Jian Liu Sep 2017

A Review Focujsed On The Psychological Effectiveness Of Tai Chi On Different Populations, Long Zhang, Thomas Lowder, Jian Liu

Jian Liu

No abstract provided.


Aging Effect On Foot Dynamics During Unexpected Slips, Jian Liu, Thurmon E. Lockhart Sep 2017

Aging Effect On Foot Dynamics During Unexpected Slips, Jian Liu, Thurmon E. Lockhart

Jian Liu

Slip-induced fall accidents have been recognized as a serious threat to the health of the elderly.The objective of the current study was to investigate the aging effect on the biomechanical reactions of both perturbed foot and unperturbed foot to the unexpected slips. Nineteen younger (mean age: 25.0 years old) and twenty-one older (mean age: 71.2 years old) adults were involved in a laboratory study,in which slippery surface was induced during walking without their awareness.The reactive responses of both slipping foot and unperturbed foot were quantified by optical motion capture system and force platforms.The results indicate a characteristic toe-touch strategy by …


Processus De Décision Et Complexité: Le Feu De Yarnell Hill Du 30 Juin 2013 [Decision-Making Processes And Complexity: The Yarnell Hill Fire Of June 30th, 2013], Karim Hardy, Louise K. Comfort Aug 2017

Processus De Décision Et Complexité: Le Feu De Yarnell Hill Du 30 Juin 2013 [Decision-Making Processes And Complexity: The Yarnell Hill Fire Of June 30th, 2013], Karim Hardy, Louise K. Comfort

Karim Hardy

Re-forming the information stream in decision processes after severe accidents allows scientists aRecréer les flux d’information au sein des processus de décision après une catastrophe permet aux chercheurs ainsi qu’aux décideurs d’identifier les points à partir desquels une action défaillante débute ainsi que les écarts dans les processus d’information qui pourraient être corrigés afin de réduire les futurs lors de futurs incidents. Le 30 juin 2013, le feu de Yarnell Hill en Arizona (Etats-Unis) évolue rapidement dans des conditions environnementale et managériale très difficiles menant à l’effondrement de la stratégie de lutte et à la perte de dix-neuf sapeurs-pompiers de …


Hazard Mitigation Through A Systemic Model Of Accident To A Socio-Technical System: A Case Study, Karim Hardy, Franck Guarnieri Aug 2017

Hazard Mitigation Through A Systemic Model Of Accident To A Socio-Technical System: A Case Study, Karim Hardy, Franck Guarnieri

Karim Hardy

This paper presents the STAMP (systems-theoretic accident modeling and processes) accident model, based on systems theory, and describes its application in the context of risk prevention related to the remediation of contaminated sediments. The implementation of the model is described, and results are presented both in methodological and technical terms. The goal of this article is to emphasize the need of new approaches to take into account hazards and accidents within socio-technical systems.


Decisions Management During Wildland Fires: Accidents Viewed As A Spatiotemporal Inadequacy, Karim Hardy Aug 2017

Decisions Management During Wildland Fires: Accidents Viewed As A Spatiotemporal Inadequacy, Karim Hardy

Karim Hardy

Extreme situations as wildland fires are a source of stress and pressure. In such events, decision-makers and incident commanders need to address a specific problem: how to manage time and resources to make meaningful decisions? Current models of accidents that exist to explain and manage catastrophes and disasters are inadequate and insufficient to deal with resources and time pressure due to uncertainty within a complex organization. Current incident response structures are incompetent and impotent to handle effectively a dynamic evolution of space and time in order to bring a situation back to stability adequately.


Modelling And Hazard Analysis For Contaminated Sediments Using Stamp Model, Karim Hardy, Franck Guarnieri Aug 2017

Modelling And Hazard Analysis For Contaminated Sediments Using Stamp Model, Karim Hardy, Franck Guarnieri

Karim Hardy

Processes for remediation (removal of pollution or contaminants) of contaminated sediments have been very efficient. These technologies, which are particularly complex, call for a comprehensive approach to risk analysis which characterises all threats (to humans, equipment, local residents, the environment, etc.) . The STAMP accident model (Systems-Theoretic Accident Model and Processes) is an example of such a comprehensive approach, and it has been chosen to characterise the risks associated with Novosol (registered trademark), an innovative remediation process.


Modelling And Hazard Analysis For Contaminated Sediments Using Stamp Model And Stpa Tool, Karim Hardy, Franck Guarnieri Aug 2017

Modelling And Hazard Analysis For Contaminated Sediments Using Stamp Model And Stpa Tool, Karim Hardy, Franck Guarnieri

Karim Hardy

The goal of this article is dual: first, introducing a new model of accident named STAMP (systems-theoretic accident modeling and processes); then applying the model to an innovative process for the treatment of contaminated substances and the re-use of treated substances. This article is a demonstration for a need of a new tool to take into account hazards and safety within socio-technical systems.


Capturing Cognitive Fingerprints From Keystroke Dynamics, J. Morris Chang, Chi-Chen Fang, Kuan-Hsing Ho, Norene Kelly, Pei-Yuan Wu, Yixiao Ding, Chris Chu, Stephen B. Gilbert, Amed E. Kamal, Sun-Yuan Kung Jun 2017

Capturing Cognitive Fingerprints From Keystroke Dynamics, J. Morris Chang, Chi-Chen Fang, Kuan-Hsing Ho, Norene Kelly, Pei-Yuan Wu, Yixiao Ding, Chris Chu, Stephen B. Gilbert, Amed E. Kamal, Sun-Yuan Kung

Morris Chang

Conventional authentication systems identify a user only at the entry point. Keystroke dynamics can continuously authenticate users by their typing rhythms without extra devices. This article presents a new feature called cognitive typing rhythm (CTR) to continuously verify the identities of computer users. Two machine techniques, SVM and KRR, have been developed for the system. The best results from experiments conducted with 1,977 users show a false-rejection rate of 0.7 percent and a false-acceptance rate of 5.5 percent. CTR therefore constitutes a cognitive fingerprint for continuous. Its effectiveness has been verified through a large-scale dataset. This article is part of …


Balancing Research And Funding Using Value Of Information And Portfolio Tools For Nanomaterial Risk Classification Jan 2016

Balancing Research And Funding Using Value Of Information And Portfolio Tools For Nanomaterial Risk Classification

Jeffrey Keisler

Risk research for nanomaterials is currently prioritized by means of expert workshops and other deliberative processes. However, analytical techniques that quantify and compare alternative research investments are increasingly recommended. Here, we apply value of information and portfolio decision analysis—methods commonly applied in financial and operations management—to prioritize risk research for multiwalled carbon nanotubes and nanoparticulate silver and titanium dioxide. We modify the widely accepted CB Nanotool hazard evaluation framework, which combines nano- and bulk-material properties into a hazard score, to operate probabilistically with uncertain inputs. Literature is reviewed to develop uncertain estimates for each input parameter, and a Monte Carlo …


Operational Resilience: Concepts, Design And Analysis, Alexander A. Ganin, Emanuelle Massaro, Alexander Gutfraind, Nicholas Steen, Jeffrey Keisler, Alexander Kott, Rami Mangoubi, Igor Linkov Jan 2016

Operational Resilience: Concepts, Design And Analysis, Alexander A. Ganin, Emanuelle Massaro, Alexander Gutfraind, Nicholas Steen, Jeffrey Keisler, Alexander Kott, Rami Mangoubi, Igor Linkov

Jeffrey Keisler

Building resilience into today’s complex infrastructures is critical to the daily functioning of society and
its ability to withstand and recover from natural disasters, epidemics, and cyber-threats. This study
proposes quantitative measures that capture and implement the definition of engineering resilience
advanced by the National Academy of Sciences. The approach is applicable across physical, information,
and social domains. It evaluates the critical functionality, defined as a performance function of time set
by the stakeholders. Critical functionality is a source of valuable information, such as the integrated
system resilience over a time interval, and its robustness. The paper demonstrates the formulation …


Adaptation Of Forward Military Airspace Management For Civilian Uas Emergency Services Operations, John C. Griffith Ph.D., Brent A. Terwilliger Ph.D. Jan 2016

Adaptation Of Forward Military Airspace Management For Civilian Uas Emergency Services Operations, John C. Griffith Ph.D., Brent A. Terwilliger Ph.D.

John Griffith

Potential use of unmanned aircraft system (UAS) to save lives, improve safety, and protect property has generated preliminary research in three major areas of the fire service, including aviation, structure and wildland scenarios.   Roadblocks to the effective use of UAS technology will be discussed with a focus on command, control, and communication (C3) issues and governmental actions to limit the use of UAS due to aviation integration safety concerns.  The results of this research will include presented adaptation of Joint Terminal Air Controller (JTAC) methodology, typically used for military command and control (Deptula & Dahl, 2003), for civilian emergency services …


A Household-Level Approach To Staging Wildfire Evacuation Warnings Using Trigger Modeling, Dapeng Li Oct 2015

A Household-Level Approach To Staging Wildfire Evacuation Warnings Using Trigger Modeling, Dapeng Li

Dapeng Li

Wildfire evacuation trigger points are prominent geographic features (e.g., ridges, roads, and rivers) utilized in wildfire evacuation and suppression practices, such that when a fire crosses a feature, an evacuation is recommended for the communities or firefighters in the path of the fire. Recent studies of wildfire evacuation triggers have used Geographic Information Systems (GIS) and fire-spread modeling to calculate evacuation trigger buffers around a location or community that provide a specified amount of warning time. Wildfire evacuation trigger modeling has been applied in many scenarios including dynamic forecast weather conditions, community-level evacuation planning, pedestrian evacuation, and protecting firefighters. However, …


From Human Reliability To Resilience & System Performance - Adapting To A Changing World, Gesa Praetorius, Fulko C. Van Westrenen Oct 2015

From Human Reliability To Resilience & System Performance - Adapting To A Changing World, Gesa Praetorius, Fulko C. Van Westrenen

Gesa Praetorius

Presentation given at the IALA Human Factors in VTS workshop, 11 October 2015, Gothenburg, Sweden.


Applying Fram To Enhance Formal Safety Assessment In The Maritime Domain, Gesa Praetorius May 2015

Applying Fram To Enhance Formal Safety Assessment In The Maritime Domain, Gesa Praetorius

Gesa Praetorius

Presentation given at the Functional Resonance Analysis Method (FRAM) workshop in Olten, Switzerland, 12 June 2015.


The Study Of Safety Governance For Service Robots: On Open-Texture Risk, Yueh-Hsuan Weng May 2014

The Study Of Safety Governance For Service Robots: On Open-Texture Risk, Yueh-Hsuan Weng

Yueh-Hsuan Weng

The emergence of steam and microelectrical machines in society gradually expanded since the era of the Industrial Revolution. Up until now, human beings have already co-existed with these machines for more than two centuries, and contemporary laws have developed preventional regulatory frameworks. These frameworks are based on risk assessments to supervise the safety of microelectrical machines which include automobiles, railway systems, elevators and industrial robots, etc. Regulators, especially South Korea and Japan expect human-robot co-existence societies to emerge within the next decade. These next generation robots will be capable of adapting to complex, unstructured environments and interact with humans to …


La Información A Los Consumidores Sobre La Ausencia O La Presencia Reducida De Gluten En Los Alimentos: El Reglamento De Ejecución (Ue) Nº 828/2014 De La Comisión, Luis González Vaqué Dec 2013

La Información A Los Consumidores Sobre La Ausencia O La Presencia Reducida De Gluten En Los Alimentos: El Reglamento De Ejecución (Ue) Nº 828/2014 De La Comisión, Luis González Vaqué

Luis González Vaqué

The Commission adopted on 30 July 2014 the Implementing Regulation (EU) No 828/2014 on the requirements for the provision of information to consumers on the absence or reduced presence of gluten in food. Information on the presence of gluten in food should help people intolerant to gluten to identify and choose a varied diet when eating inside or outside the home. Wheat, rye and barley have been identified as grains that are scientifically reported to contain gluten. The gluten present in those grains can cause adverse health effects to people with coeliac disease and therefore its consumption should be avoided …


National Infrastructure Protection Priorities For Nuclear Electromagnetic Pulse (Emp) And Solar Storm Geomagnetic Disturbance Catastrophes, George H. Baker Iii Jun 2013

National Infrastructure Protection Priorities For Nuclear Electromagnetic Pulse (Emp) And Solar Storm Geomagnetic Disturbance Catastrophes, George H. Baker Iii

George H Baker

The Commission to Assess the Threat to the United States from Electromagnetic Pulse Attack has provided a compelling case for protecting civilian infrastructure against the effects of EMP and geomagnetic disturbances (GMD) caused by severe solar storms. Similar to protecting critical infrastructure against any hazard, it will be important to take a risk-based priority approach for these two electromagnetic threats, recognizing that it will be fiscally impracticable to protect everything. In this regard, EMP and GMD are particularly challenging in that they interfere with electrical and electronic data, control, transmission, and communication systems organic to nearly all critical infrastructures, simultaneously, …


Risky Removal: Developing A Holistic Understanding Of The Risks Of Redeveloping Sites Contaminated With Unexploded Ordnance, Matthew Bates, Elizabeth Jones, Jeffrey Keisler, Igor Linkov Mar 2013

Risky Removal: Developing A Holistic Understanding Of The Risks Of Redeveloping Sites Contaminated With Unexploded Ordnance, Matthew Bates, Elizabeth Jones, Jeffrey Keisler, Igor Linkov

Jeffrey Keisler

No abstract provided.


From Cyber Terrorism To State Actors’ Covert Cyber Operations, Jan Kallberg, Bhavani Thuraisingham Mar 2013

From Cyber Terrorism To State Actors’ Covert Cyber Operations, Jan Kallberg, Bhavani Thuraisingham

Jan Kallberg

Historically, since the Internet started to become a common feature in our lives, hackers have been seen as a major threat. This view has repeatedly been entrenched and distributed by media coverage and commentaries through the years. Instead the first twenty year of the Internet was acceptably secure, due to the limited abilities of the attackers, compared to the threat generated from a militarized Internet with state actors conducting cyber operations. In reality, the Internet have a reversed trajectory for its security where it has become more unsafe over time and moved from a threat to the individual to a …


Nuclear Deterrence In A Second Obama Term, Adam Lowther, Jan Kallberg Mar 2013

Nuclear Deterrence In A Second Obama Term, Adam Lowther, Jan Kallberg

Jan Kallberg

In the months prior to the 2012 presidential election in the United States, members of the Obama administration and sympathetic organizations inside the Beltway began floating the idea that the administration would pursue – after an Obama victory – further reductions in the US nuclear arsenal. With the ink still wet on the New ST ART Treaty, efforts to reduce the American arsenal to 1000 operationally deployed strategic nuclear weapons or, as some suggest, 500, is certainly premature. These efforts illustrate a poor understanding of nuclear deterrence theory and practice and the ramifications of a United States that lacks a …


Scenario Analysis: A Review Of Methods And Applications For Engineering And Environmental Systems, Yousra Tourki, Jeffrey Keisler, Igor Linkov Feb 2013

Scenario Analysis: A Review Of Methods And Applications For Engineering And Environmental Systems, Yousra Tourki, Jeffrey Keisler, Igor Linkov

Jeffrey Keisler

Changing environment, uncertain economic conditions, and socio-political unrest have renewed interest in scenario analysis, both from theoretical and applied points of view. Nevertheless, neither the processes for scenario analysis (SA) nor evaluation criteria and metrics have been regularized. In this paper, SA-reported applications and implementation methodology are discussed in the context of an extensive literature review covering papers published between 2000 and 2010. Over 340 papers were identified through a series of queries in the web of science database. The papers were classified based on the North American Industrial Classification System and SA application goals (environmental, business, and social). SA …


Offensive Cyber: Superiority Or Stuck In Legal Hurdles?, Jan Kallberg Feb 2013

Offensive Cyber: Superiority Or Stuck In Legal Hurdles?, Jan Kallberg

Jan Kallberg

In recent years, offensive cyber operations have attracted significant interest from the non-Defense Department academic legal community, prompting numerous articles seeking to create a legal theory for cyber conflicts. Naturally, cyber operations should be used in an ethical way, but the hurdles generated by the legal community are staggering. At a time when the United States has already lost an estimated $4 trillion in intellectual property as a result of foreign cyber espionage, not to mention the loss of military advantage, focusing on what the United States cannot do in cyberspace only hinders efforts to defend the country from future …


Europe In A ‘Nato Light’ World - Building Affordable And Credible Defense For The Eu, Jan Kallberg, Adam Lowther Jan 2013

Europe In A ‘Nato Light’ World - Building Affordable And Credible Defense For The Eu, Jan Kallberg, Adam Lowther

Jan Kallberg

From an outsider’s perspective, the Common Security and Defense Policy and the efforts of the European Defense Agency are insufficient to provide Europe with the defense it will require in coming decades. While the European Union—particularly the members of the European Monetary Union—struggle to solve prolonged fiscal challenges, viable European security alternatives to an American-dominated security architecture are conspicuously absent from the documents and discussions that are coming from the European Council and at a time when the United States is engaged in an Asia-Pacific pivot. This is not to say that no thought has been given to defense issues. …


Cyber Operations Bridging From Concept To Cyber Superiority, Jan Kallberg, Bhavani Thuraisingham Jan 2013

Cyber Operations Bridging From Concept To Cyber Superiority, Jan Kallberg, Bhavani Thuraisingham

Jan Kallberg

The United States is preparing for cyber conflicts and ushering in a new era for national security. The concept of cyber operations is rapidly developing, and the time has come to transpose the conceptual heights to a broad ability to fight a strategic cyber conflict and defend the Nation in a cohesive way. Richard M. George, a former National Security Agency official, commented on recent developments: “Other countries are preparing for a cyberwar. If we’re not pushing the envelope in cyber, somebody else will.”1 Therefore, increased budgets are allocated to cyber operations research and education. The Defense Advanced Research Projects …