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Full-Text Articles in Civil Engineering

Assessing The Perceived Safety Of Cyclists With Virtual Reality, Vahid Balali Mar 2025

Assessing The Perceived Safety Of Cyclists With Virtual Reality, Vahid Balali

Mineta Transportation Institute

In 2022, 7,522 pedestrians and 1,084 bicyclists were killed and approximately 67,000 pedestrians and 46,195 bicyclists injured in motor vehicle crashes on public roadways in the United States, according to the Insurance Institute for Highway Safety (IIHS). The transportation industry is faced with a pressing need to bolster the safety of these vulnerable road users. This research develops models of design and environmental factors that influence bicyclists’ and pedestrians’ perception of safety using Virtual Reality (VR) technology and ultimately informs transportation infrastructure design to better accommodate nonmotorized travelers. The goal of the bicycle element of this research is to develop …


Safety Investigation Of Crash Rates During Hurricane Evacuations, Amelia K. Lawson Mar 2024

Safety Investigation Of Crash Rates During Hurricane Evacuations, Amelia K. Lawson

Doctoral Dissertations and Master's Theses

This study aimed to investigate crash rates across four distinct periods—evacuation, re-entry, emergency, and non-emergency—during Hurricanes Matthew (2016), Irma (2017), and Michael (2018). A notable gap in existing research pertains to understanding crash rates during these critical phases of hurricane events. By addressing this gap, this research contributes to a deeper comprehension of evacuation transportation safety. The methodology employed ArcMap to construct an interactive map for data collection, encompassing key variables such as the number of crashes, traffic volumes, duration of each period under analysis, and roadway segment lengths for each hurricane. Evaluating the crash rate per million vehicular miles …


Evaluation Of Driveway Assistance Device (Dad) Systems In One-Lane Two-Way Work Zone, Mm Shakiul Haque, Aemal J. Khattak, Li Zhao Jan 2024

Evaluation Of Driveway Assistance Device (Dad) Systems In One-Lane Two-Way Work Zone, Mm Shakiul Haque, Aemal J. Khattak, Li Zhao

Mid-America Transportation Center: Final Reports and Technical Briefs

Lane closure on two-lane highways due to the presence of work zones negatively impacts traffic safety and operational efficiency. Additionally, traffic from access points (e.g., commercial and residential driveways, or minor side roads) within work zones make operations more complicated and inefficient. Deploying a driveway assistance device (DAD) system can enable more efficient traffic control for work zones with access points. While traffic agencies are becoming interested in DAD deployments, research on such systems is relatively sparse. This research was the first in-depth operational investigation of the DAD system under different signal strategies, traffic conditions, and work zone characteristics. This …


Performance Reliability And Safety Index For Region Vii Highways, Aemal J. Khattak, Mm Shakiul Haque, Li Zhao Jan 2024

Performance Reliability And Safety Index For Region Vii Highways, Aemal J. Khattak, Mm Shakiul Haque, Li Zhao

Mid-America Transportation Center: Final Reports and Technical Briefs

Roadway performance measures are used for operating, planning, and design purposes to improve services for road users. Simple statistics of the performance metrics such as measures of central tendency (e.g., mean, median) are often used for making operational and planning decisions. Even though such statistics are useful, they are, more than often, not comprehensive enough for making insightful operational and planning decisions. Consequently, performance reliability measures, which attempt to capture the day-to-day variability in performance, have the potential to benefit the areas of operation, planning, and design. Traffic data from Intelligent Transportation System facilitates the measurement of the reliability of …


Application Of Machine Learning Models To Predict Driver Left Turn Destination Lane Choice Behavior At Urban Intersections, Mohammed Moinuddin, Logan Proffer, Matthew Vechione, Aaditya Khanal Dec 2023

Application Of Machine Learning Models To Predict Driver Left Turn Destination Lane Choice Behavior At Urban Intersections, Mohammed Moinuddin, Logan Proffer, Matthew Vechione, Aaditya Khanal

Civil Engineering Faculty Publications and Presentations

When there are multiple lanes to choose from downstream of a turning movement, drivers should choose the innermost lane so that drivers at other approaches of the intersection may make concurrent turning movements in the outermost lane(s). However, human drivers do not always choose the innermost lane, which could lead to crashes with other vehicles. Therefore, predicting human driver behaviors is vital in reducing crashes, as the need to share the roadways with automated vehicles (AVs) continues to grow. In this research, various machine learning models have been used to predict the left turn destination lane choice of human-driven vehicles …


Use Of Harsh-Braking Data From Connected Vehicles As A Surrogate Safety Measure, Nathaniel Patrick Edelmann Dec 2022

Use Of Harsh-Braking Data From Connected Vehicles As A Surrogate Safety Measure, Nathaniel Patrick Edelmann

Boise State University Theses and Dissertations

Traffic safety may be analyzed with the use of surrogate safety measures, measures of safety that do not incorporate collision data but rather rely on the concept of traffic conflicts. Use of these measures provides several benefits over use of more traditional analysis methods with historical crash data. Surrogate measures eliminate the need to wait for crashes to occur to conduct a safety analysis. The amount of time required for enough crash data to accumulate can be significant, delaying safety analyses. Similarly, these measures allow for safety analysis to be conducted prior to crashes occurring, potentially calling attention to hazardous …


Fault Tolerance Analysis Of An Adaptive Neuro-Fuzzy Inference System For Mandatory Lane Changing Decisions In Automated Driving, Matthew Vechione, Ruey Long Cheu Jun 2022

Fault Tolerance Analysis Of An Adaptive Neuro-Fuzzy Inference System For Mandatory Lane Changing Decisions In Automated Driving, Matthew Vechione, Ruey Long Cheu

Civil Engineering Faculty Publications and Presentations

Past research has developed a binary decision model for mandatory lane changes based on the Adaptive Neuro-Fuzzy Inference System (ANFIS). This ANFIS Decision Model (simply called ADEM), developed and tested with the Next Generation Simulation (NGSIM) data, mimics the sensory inputs and decisions of human drivers. This research assumed that ADEM will be implemented as part of the automated lane changing system in Automated Vehicles (AVs). The system in AVs will depend on active radar sensors to make measurements. The sensor outputs will be converted into the input parameter values of ADEM. This research tested ADEM's performance when the sensors …


Risk And Safety Associated With Hazardous Materials Transport In Rural And Native American Communities: A Case Study Of Thurston County, Nebraska, Sydney James May 2021

Risk And Safety Associated With Hazardous Materials Transport In Rural And Native American Communities: A Case Study Of Thurston County, Nebraska, Sydney James

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Rural counties and Native American Reservations often lack the resources and planning to respond to a hazardous material release which can cause catastrophic results. Many rural counties and Native American Reservations do not have close access to a fire department or medical facility, which would increase response times during a time of crisis. Jurisdiction issues further complicate the matter since Native American Reservations are sovereign nations,.

Thurston County, home to two Native American Reservations, served as a case study to perform a safety analysis for vehicles transporting hazardous material. Stakeholders within the county from tribal, county, and state levels were …


Adaptive Signal System Safety Impacts Final Report, Mashrur Chowdhury, Weiman Jin, M. Sabbir Salek, Sakib Mahmud Khan, Katherine Brunk, Patrick Gerard, Nathan Huynh, Mohammad Torkjazi Feb 2021

Adaptive Signal System Safety Impacts Final Report, Mashrur Chowdhury, Weiman Jin, M. Sabbir Salek, Sakib Mahmud Khan, Katherine Brunk, Patrick Gerard, Nathan Huynh, Mohammad Torkjazi

Publications

The research team conducted a literature review and a nation-wide survey at the beginning of the research. The literature review revealed that Adaptive Signal Control System (ASCS) was effective in reducing crashes in some studies, while in other studies, the crash reduction due to ASCS was not statistically significant. Twenty-eight states participated in the nation-wide survey and helped the research team identify corridor characteristics, such as the design speed and Annual Average Daily Traffic (AADT) of an ASCS corridor, which would allow for the best operational and safety outcomes. Then, to determine the safety effects of ASCS, the research team …


Effective Communication Message Strategy For Enhancing Traffic Safety In Fresno County: The Role Of Time Horizon, Regulatory Focus, And Perceived Personal Control, Samer Sarofim Jun 2020

Effective Communication Message Strategy For Enhancing Traffic Safety In Fresno County: The Role Of Time Horizon, Regulatory Focus, And Perceived Personal Control, Samer Sarofim

Mineta Transportation Institute

This research empirically investigated the differential effect of message framing on message recipients’ attitudes and intended behaviors related to pedestrian, cyclist, and motorist traffic safety practices. The framework empirically investigated time horizon (expansive vs. limited) and regulatory focus (prevention vs. promotion) message framing.

The time horizon in the message can make someone either think of the future (expansive) or the present (limited). For example, an expansive time horizon message communicates that life is long and directs the focus on the future. On the contrary, a limited time horizon message communicates that life is short and directs the focus on the …


Analysis Of The Effects Of Adaptive Ramp Metering On Measures Of Efficiency With A Proposed Framework For Safety Evaluation, Jacky Loh Jun 2019

Analysis Of The Effects Of Adaptive Ramp Metering On Measures Of Efficiency With A Proposed Framework For Safety Evaluation, Jacky Loh

Master's Theses

Adaptive ramp metering (ARM) is a widely popular intelligent transportation system (ITS) tool that boasts the ability to reduce congestion and streamline traffic flow during peak hour periods while maintaining a lower implementation cost than traditional methods such as freeway widening. This thesis explores the effectiveness of ARM implementation on an 18 mile segment of the Interstate 80 (I-80) corridor in the Bay Area residing in northern California. Smaller segments of this particular segment were analyzed to determine the effective length of ARM on efficiency at various lengths originating from a known bottleneck location. Efficiency values were also compared against …


Novel Infrastructure Monitoring Using Multifaceted Unmanned Aerial Vehicle Systems - Close Range Photogrammetry (Uav - Crp) Data Analysis, Surya Sarat Chandra Congress Dec 2018

Novel Infrastructure Monitoring Using Multifaceted Unmanned Aerial Vehicle Systems - Close Range Photogrammetry (Uav - Crp) Data Analysis, Surya Sarat Chandra Congress

Civil Engineering Dissertations - Archive

Remote sensing is a method of collecting data without making any physical contact with the object under inspection. Modern day remote sensing kicked off with the invention of the camera and continued on to the invention of advanced satellite mounted sensors. Photogrammetry is defined as a science that measures distances using one or more images captured remotely. Remote collection of images within a range of 1000 ft is termed close-range photogrammetry (CRP). Unmanned aerial vehicle systems (UAV or UAS) have become a popular means of remotely gathering information and assessing infrastructure conditions due to their versatile nature. Multirotor and fixed-wing …


Measuring And Evaluating Safety Maturity Of Construction Contractors: Multicriteria Decision-Making Approach, Ali A. Karakhan, Sathyanarayanan Rajendran, John Gambatese, Chukwuma Nnaji Jul 2018

Measuring And Evaluating Safety Maturity Of Construction Contractors: Multicriteria Decision-Making Approach, Ali A. Karakhan, Sathyanarayanan Rajendran, John Gambatese, Chukwuma Nnaji

All Faculty Scholarship for the College of the Sciences

Evaluating the safety maturity of construction contractors before awarding the contract is an effective strategy that many owners have started to implement. Given the importance of workplace safety, awarding the contract to safer contractors can enhance project performance outcomes in terms of safety, quality, cost, and schedule. Safety maturity is one quality of a construction organization encompassing interdependent factors that can be used to evaluate expected safety performance. However, there is no formal decision-making framework available in literature that owners can use to evaluate contractor safety maturity. The present study aims to bridge this gap in safety knowledge by proposing …


Transforming Yekaterinburg Into A Safe, Resilient-Smart And Sustainable City, S. A. Timashev, V. N. Alekhin, L. V. Poluyan, I. Fontanals, A. Gheorghe Jan 2018

Transforming Yekaterinburg Into A Safe, Resilient-Smart And Sustainable City, S. A. Timashev, V. N. Alekhin, L. V. Poluyan, I. Fontanals, A. Gheorghe

Engineering Management & Systems Engineering Faculty Publications

The initiative (since 2014) project described in this paper is a product of a joint innovative research and implementation effort of the Civil Engineering and Architecture Institute, Ural Federal University, the Science and Engineering Centre "Reliability and Safety of Large Systems and Machines", Ural Branch Russian Academy of Sciences (both Yekaterinburg), Start-up OptiCits, Barcelona, Spain and the Old Dominion University, Norfolk, VA, USA. The project is based on using the MAICS convergent technology [1] to create a versatile multi-purpose tool for optimizing the science and art of risk based governance of resilience-smart and sustainable city infrastructure and communities operating in …


A Hierarchical Modelling Approach For Assessing The Impact Factors Of The Measured Of Mobility And Safety At Intersections, Hiba Eyesha Abou-Kassem Sep 2017

A Hierarchical Modelling Approach For Assessing The Impact Factors Of The Measured Of Mobility And Safety At Intersections, Hiba Eyesha Abou-Kassem

Civil and Environmental Theses

Measuring safety and mobility for various types of intersections is crucial in any transportation study. Many factors contribute to changing the effectiveness of the different types of intersections on mobility and safety. Deciding which type of intersection is most suitable in a particular environ and prevailing traffic conditions depends on the number of crashes, injuries, delay time, etc. This study focuses on two intersection types; signalized intersections and non-signalized intersections (only roundabouts). The aim of this research is to devise a theoretical modeling framework and hence a statistical-based methodology that can be used to assess the safety and mobility measures …


Recommendation Of A New Transit Performance Measure In The National Transit Database, Fatemeh Baratian-Ghorghi, Hossein Ahmadianyazdi Jun 2017

Recommendation Of A New Transit Performance Measure In The National Transit Database, Fatemeh Baratian-Ghorghi, Hossein Ahmadianyazdi

Journal of Public Transportation

The frequency of incidents negatively changes public perception with regard to the public safety in transit systems. The level of safety expressed as performance measures, ensures contractors and users that a quality safety level is maintained. Both the private and public sectors in the U.S. annually report accurate data to the National Transit Database (NTD) to be used in assessing the progress of the nation's public transportation systems. Although they must provide both the annual report and monthly reports including Safety and Security data, measures are only grouped into the indicators of efficiency and effectiveness of a system and there …


Industrial-Grade Monitoring Solution: Hoistcam, Purdue Ect Team Apr 2017

Industrial-Grade Monitoring Solution: Hoistcam, Purdue Ect Team

ECT Fact Sheets Archive

Safety and productivity are top priorities for contractors and industrial operations. Improving either makes a company more profitable and competitive. Technology advancements that can do both are important for every company to consider. HoistCamTM industrial-grade video monitoring solutions can improve employees’ productivity and workplace safety in the construction industries. HoistCam also improves efficiency of operations and reduces job site accidents resulting in substantial cost savings to a contractor.

HoistCam™ is an integrated, wireless video system. The use of HoistCam eliminates blind lifts, blind spots and can share the live video with anyone, anywhere with solid security and easy control. …


Evaluation Of Milwaukee B And Synchronized As New Service Interchange Designs, Amirarsalan Mehrara Molan Jan 2017

Evaluation Of Milwaukee B And Synchronized As New Service Interchange Designs, Amirarsalan Mehrara Molan

Wayne State University Dissertations

These days, alternative interchanges are attracting the attention of transportation

agencies and designers more than ever. Most of the existing interchanges in the U.S

were built in the 1950s and 1960s when traffic volume was much lower, and the type of

vehicles and driving habits were completely different. Moreover, the knowledge of

highway design and safety is more developed now, and this provides an appropriate

situation to increase the efficiency of interchanges regarding traffic operation and safety

using alternative interchanges.

This research evaluated the performance of two proposed service interchange

designs—the synchronized design which is related to a superstreet intersection …


A Comprehensive Safety Analysis Of Diverging Diamond Interchanges, Holly Lloyd May 2016

A Comprehensive Safety Analysis Of Diverging Diamond Interchanges, Holly Lloyd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the implementation of new roadway configurations, there is a great need to study the influence of the roadway design on the crash rate. Utah is one of the leading states in the implementation of the Diverging Diamond Interchange.

In order to determine the effects of the new roadway configuration on the safety of the intersection, this study employs an Empirical Bayes before-after study of the crash rates at selected Diverging Diamond Interchanges in Utah. The results of the Empirical Bayes method were also used to calculate crash modification factors. The total number of crashes at each site were analyzed. …


Mining Big Data To Create A Tool For Empirical Observation Of Continuous Safety Improvement In A Construction Company - A Progressive Case Study In The Lean Environment, Nicolas J. Michuda Apr 2016

Mining Big Data To Create A Tool For Empirical Observation Of Continuous Safety Improvement In A Construction Company - A Progressive Case Study In The Lean Environment, Nicolas J. Michuda

Open Access Theses

In any iterative process, without a system of measurement, controlled improvement cannot be recorded. This is especially true in the construction industry, where error occurs, often with fatal repercussions. As part of a process to facilitate the establishment of this metric, an entirely new application was created. The goal of this application is to measure the causal factors that lead to incidents, which will allow the user and administration to track the circumstances and types of incidents. This enables the company to focus on these problem areas and improve through training. By analyzing these incident trends over time, the company …


Numerical Simulation Of Shock Response And Dynamic Fracture Of A Concrete Dam Subjected To Impact Load, Lu Lu, Xin Li, Jing Zhou, Genda Chen, Dong Yun Mar 2016

Numerical Simulation Of Shock Response And Dynamic Fracture Of A Concrete Dam Subjected To Impact Load, Lu Lu, Xin Li, Jing Zhou, Genda Chen, Dong Yun

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The shock response and dynamic fracture of concrete gravity dams under impact load are the key problems to evaluate the antiknock safety of the dam. This study aims at understanding the effects of impact shock on the elastic response and dynamic fracture of concrete gravity dams. Firstly, this paper uses acceleration records of a concrete gravity dam under impact to establish the correct way to determine the concrete gravity dam of the fundamental frequency and present cut sheets multi-degree-of-freedom dynamic modeling. Under strong impact loading, the constitutive relation of concrete gravity dam and the highest frequency of the impact are …


Child Safety Near Pot Shops In Denver, Jacob Flansberg, Elise Jackson, Amelia Theobald Jan 2016

Child Safety Near Pot Shops In Denver, Jacob Flansberg, Elise Jackson, Amelia Theobald

Engineering Applications of GIS - Laboratory Exercises

Some major factors in deciding where one’s family should live include relative safety of the neighborhood, available green space such as parks and schools, grocery stores, and other commercial retail in the area. With the legalization of marijuana in states such as Colorado, proximity of these marijuana dispensaries has become another factor. The Normalized Difference Vegetation Index (NDVI) can be used as a measure of vegetation, and to determine areas with high levels of irrigated vegetation. Using ArcGIS Modelbuilder, the data from an NDVI analysis can be used to determine the proximity of marijuana shops to these types of greenspaces …


Evaluation Of The Safety Effectiveness Of Clearview Font And Fluorescent Yellow Sheeting On Michigan Freeways And Non-Freeways, Lusanni Mercedes Acosta Rodrieuez Aug 2015

Evaluation Of The Safety Effectiveness Of Clearview Font And Fluorescent Yellow Sheeting On Michigan Freeways And Non-Freeways, Lusanni Mercedes Acosta Rodrieuez

Masters Theses

Halation or irradiation makes guide sign fonts difficult to read. Missing the necessary guide sign information causes anxiety and confusion to drivers, and hence may lead to crashes. In order to avoid or mitigate the situation a newer font, Clearview, is used to provide better readability at long distances. In a similar context the lack of brightness in sheeting material for warning signs reduces conspicuity of sings. Installation of fluorescent yellow sheeting has been done to provide signs with more noticeable and brighter materials. This observational before and after study is an evaluation of the safety and economic benefits of …


Benefits Of A State Driveway Database With Qualitative And Quantitative Crash Analysis, Andrew Bryant Stokes May 2015

Benefits Of A State Driveway Database With Qualitative And Quantitative Crash Analysis, Andrew Bryant Stokes

All Theses

The primary goal of this research is to show how a fully developed driveway database will improve access management practices resulting in a reduction in crashes, injuries, and fatalities on our roadways. The results of this thesis highlight a close relationship between driveway characteristics and the incidence of crashes. Thus, it is critical to be proactive in enforcing access management strategies and policies that are designed to enhance driveway safety without compromising the economic vitality of land use along roads. The analysis identified several significant independent variables that influence crash rates either positively or negatively. The data driven approach to …


The Relationship Between Bicycles And Traffic Safety For All Road Users, Jasmine A. Martin Dec 2014

The Relationship Between Bicycles And Traffic Safety For All Road Users, Jasmine A. Martin

Master's Theses

Over the past twenty years bicycle use as a mode of transportation has grown considerably in the United States. Other studies have examined the individual bicyclist’s risk in proportion to the growth in cycling across cities, a phenomenon referred to as ‘safety in numbers.’ This study expands from that research and examines the effect of cyclists on road safety for all road users.

The study examines the roles of bicycle modal split, a city wide analysis, and bicycle infrastructure, a site based analysis, in road safety outcomes. For the city based analysis, twenty years of crash data in 12 California …


Development Of Safety Performance Functions For Non-Motorized Traffic Safety, Hamidreza Ahady Dolatsara Jun 2014

Development Of Safety Performance Functions For Non-Motorized Traffic Safety, Hamidreza Ahady Dolatsara

Masters Theses

This study investigates the factors which affect the safety of non-motorized transportation within the influence area of intersections to enhance development of safety performance functions (SPFs). The scope of this study is limited to the four Michigan cities of Ann Arbor, East Lansing, Flint and Grand Rapids. Due to the current lack of research regarding the appropriate size of the influence area, this study investigates the distance of crashes relative to the center of 148 intersections to identify the most probable area of influence for different crash types. For motorized and non-motorized crashes, 240 ft. and 137 ft. are proposed, …


Safety Measures For Trucks: A Comparison Between Eu And U.S., Jan Kapusta Jan 2014

Safety Measures For Trucks: A Comparison Between Eu And U.S., Jan Kapusta

Open Access Theses & Dissertations

Road transportation is playing an important role in almost all of the freight movements and contributes to the economy. It has the highest share in the modal division of transported goods. This situation is not about to change in next years to come. Therefore, it is necessary to change the current situation and create rules and regulations that would lead to decrease in number of accidents either in EU or in U.S. The goal of this research is to analyze selected parameters related to the safety of truck transportation in EU and in U.S. This thesis also identifies and compares …


Driver Fatigue Enforcement Techniques And Their Effect On Crashes, Carrie Mohlman Jul 2013

Driver Fatigue Enforcement Techniques And Their Effect On Crashes, Carrie Mohlman

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Fatigued driving is a type of driver impairment caused by a lack of sleep, sleep disorders, long drive times, etc. Fatigued driving enforcement aims to improve safety by removing impaired drivers from the roadway. While fatigued driving is detrimental to safety, there exists the issue of identifying fatigue. There is a range between being awake and asleep and, in order to improve safety, enforcement officers must be able to identify the point at which drivers are impaired.

This thesis investigates potentially effective fatigued driving enforcement techniques for use by enforcement officers. These techniques were investigated through three primary means: a …


Platooning Safety And Capacity In Automated Electric Transportation, James Fishelson May 2013

Platooning Safety And Capacity In Automated Electric Transportation, James Fishelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Automated Electric Transportation (AET) proposes a system of automated platooning vehicles electrically powered by the roadway via wireless inductive power transfer. This has the potential to provide roadway transportation that is less congested, more flexible, cleaner, safer, and faster than the current system. The focus of this research is to show how platooning can be accomplished in a safe manner and what capacities such an automated platooning system can achieve. To accomplish this, first two collision models are developed to show the performance of automated platoons during an emergency braking scenario: a stochastic model coded in Matlab/Simulink and a deterministic …


New Highway Accident Location Manual For Missouri, Carlos Sun Ph.D., P.E., Jd, Praveen Edara Ph.D., P.E., Ptoe, Henry Brown M.S., P.E. Jan 2013

New Highway Accident Location Manual For Missouri, Carlos Sun Ph.D., P.E., Jd, Praveen Edara Ph.D., P.E., Ptoe, Henry Brown M.S., P.E.

Mid-America Transportation Center: Final Reports and Technical Briefs

The Missouri HAL manual is used to identify, analyze, and correct high crash locations, and has not been updated since 1999. This new edition brings the manual up to date, while incorporating the methodology of the national Highway Safety Manual (HSM). This 4th edition represents a complete re-working of all existing chapters of the manual. The changes are both stylistic and substantive. A contemporary book-style stylesheet was used to improve the appearance of figures, tables, headings, and labels. Even the title of the manual was changed from HAL (Identification, Analysis, and Correction of High-Crash Locations) to S-HAL (Safety Handbook for …