Mary E. Ahern, P.E., - Specializes in Traffic Engineering and Traffic Signal System Design and Optimization. As an Expert Witness, Ms. Ahern has experience in determining causes of vehicle accidents, investigating pavement markings, assisting in case direction and traffic solutions, preparing sight distance calculations and accident site photography analysis. She also teaches traffic engineering and geometrics as an adjunct instructor for Northwestern University.

Areas of Expertise:Red Light Cameras

Traffic Engineering Traffic Counts Traffic Warrant Studies Traffic Signal and System Design Video Vehicle Detection Audible Pedestrian Signal Design Emergency Vehicle Preemption Design Accident Analysis

Red and Amber Clearance Interval Calculations Accident Site Photography Accident Site Video Production Sight Distance Calculations Dilemma Zone Issues Procedure Development Sales Roadway Design

Degrees: Stanford Ph.D. in Engineering Mechanics (Mechanical Engineering).

Specialties: Reconstruction of vehicular accidents; mechanical failure analysis; tire failure analysis; analysis of vehicle collisions and vehicle response to operator input; dynamics, impact and vibration; computer analyses of solids, fluids, and one-of-a-kind engineering mechanics problems; applied physics.

Qualifications:

Fifteen years of litigation experience.

Registered professional mechanical engineer in California.

List of 23 technical publications available.

Fluent speaker of Spanish.

Have worked for Failure Analysis, Exxon Production Research, the Uniroyal Tire Research Center, and Lockhead Missiles and Space.

Have taught engineering at Santa Clara University.

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Steven R. Graboff, M.D. is a Diplomate of the American Board of Orthopaedic Surgery, a Diplomate of the American Board of Forensic Examiners, and a Diplomate of the American Board of Forensic Medicine. He is a member of the American College of Forensic Examiners and a Certified Forensic Physician. He has had an active Orthopaedic Surgery practice in Huntington Beach, California, since 1985, and he brings considerable expertise and experience to the forensic medical legal community.

With over 20 years of litigation support experience, Dr. Graboff has qualified and testified as an orthopedic expert witness over 400 times for both the plaintiff and defense in cases throughout the United States.

Dr. Graboff received his medical degree from the University of California, Irvine in 1980. He did a general surgery internship at the University of California Irvine Medical Center and affiliated hospitals from 1980 - 1981, and he completed his Orthopaedic Surgery training in 1985 from Harbor-UCLA Medical Center and affiliated hospitals, Los Angeles, California.

Dr. Graboff was first certified by the American Board of Orthopaedic Surgeons in 1987. He has been re-certified by the Board in January 1998 and most recently re-certified effective January 2008. He is a Diplomate of the National Board of Medical Examiners and is appointed by the State of California as a Qualified Medical Examiner.

Dr. Graboff is a member of the American College of Forensic Examiners, the American Medical Association, the California Medical Association, the Orange County Medical Association, the California Orthopaedic Association, the Association of University Professors, the California Faculty Association, and the California Teachers Association. He has volunteered his services as the team physician for the Garden Grove School District for 10 years and participated in the CIF Southern Section Athletic Safety Commission.

Dr. Graboff has been teaching Orthopedics, differential diagnosis, and musculoskeletal radiology in the Department of Physical Therapy, California State University, Long Beach, College of Health and Human Services, for over 10 years. He is a guest lecturer at the University Of California Irvine School Of Medicine and an Instructor in the Clinical Foundations teaching program. He is a medical specialist and advisor for the City of Huntington Beach Emergency Operations Center, and he volunteers his services with the Medical Reserve Corps, Orange County, California.

Ralph Aronberg, P.E., has reconstructed over 1,500 accidents and has testified in over 150 jury trials, since founding the firm in 1983. He provides Expert Witness services in the areas of:

Traffic accident reconstruction (cars, trucks, motorcycles and pedestrians).

Vehicle occupant kinematics (seatbelts)

Biomechanics

Traffic engineering design (geometrics, signing, markings, signals and lighting)

Sight distance analysis

Hazardous roadway conditions

Work Zone Traffic Control evaluation

Evaluation of roadway curvature

Traffic signal operations

Pedestrian safety

Computerized accident reconstruction and simulation

Vehicle "black box" data retrieval (certified>

Mr. Aronberg is published in the fields of pedestrian / bicycle / motorcycle accident reconstructions, and 3 Dimensional Animations and Scientific Visualizations through the Society of Automotive Engineers. Mr. Aronberg is a Fellow member of the National Academy of Forensic Engineers, and certified as a Diplomat in forensic Engineering.

Dr. Richard Collins, Former University Professor of Biomedical and Human Factors Engineering, Professor of Medicine, Professor of Mechanical and Aerospace Engineering. Dr. Collins has Demonstrated Accuracy in Research and Scientific Analysis in Mechanical and Biomechanical Engineering and Regulatory Assessments.

His work has been Extensively Published in National and International peer-reviewed Literature. He is an Internationally recognized engineering and medical expert, having earned his Ph.D. from the University of California, Berkeley. Dr. Collins is qualified as an expert witness in civil and criminal courts.

Areas of Specialization:

Wrongful Death, Medical Malpractice, Medical Device / Product Liability

Head and Spine Injury Cases in Motorcycle, Bicycle Collisions, Protective Helmet Liability

Accident Reconstruction / Failure Analysis - Serious Personal Injury and Trauma

Analysis / Injury Biomechanics: Automotive, Traffic Safety, Aircraft Crashes, Train Crashes, Forklift Turnovers, Elevator Failures, Sports Impacts, Sports, Recreational and Safety Equipment, Sports and Industrial Injuries, Ergonomics, Repetitive Stress Cases, Slips and Falls

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Bison is a multi-disciplined engineering firm specializing in failure analysis, forensic engineering and fire sciences with a team of P.E.'s who have performed thousands of forensic assignments including in excess of 1,000 fuel gas investigations.

Legal professionals turn to Bison to scientifically conduct investigations to determine the cause of destructive events. Forensic Engineers provide expert testimony and consultation. Investigations include explosions, fires, carbon monoxide incidents, electrical fires and failures, structural failures, mechanical failures, accident reconstruction, specialized testing, and courtroom presentations:

Fuel Gas Incidents: Fire and Explosion Causation; Propane Explosions, Natural Gas Explosion, Gas Delivery Systems; Carbon Monoxide Testing and Evaluation, Production and Migration Investigations; Plant & Pipeline, Piping Evaluation; Operational Analysis; Appliance Evaluation; Code Compliance; Soil Gas Migration; Vapor Dispersion

Fire Investigation and Explosion Analysis: Cause and Origin, Scene Documentation; Collection of Evidence; Certified Fire Investigator

Electrical Engineering: Electrically Related Fires, Electrical Service and Wiring Failures, Production Facility Service and Controls for Chemical, Petroleum, and Distribution Facilities, Electrical Contacts, Electrocutions; Lightning Strikes

Mechanical Engineering: Equipment Design and Operation; High-Pressure Oilfield Equipment; Pump Design and Operation; HVAC Systems; High and Low-Pressure Seals; Plastic Part Design and Manufacture, Industrial Equipment

Accident Reconstruction: Accident Sequence Reconstruction; Speed, Time and Distance Calculations; Crush Damage; Braking; Steering and Mechanical Analysis, including Tires; Electrical System / Electronic Failures; Mechanical and Fuel Systems; Airbag and Seatbelt Fatalities/Injuries; Staged Vehicle Impact

Failure Analysis: Industrial Equipment, Vehicle Impacts, Airbags and Seat Belts; Elevator Failures; Helmet and other Protective Equipment Failures; Infant Crib Design Inadequacies; Carbon Monoxide Investigations, Crane Failures, etc.

Metallurgical Engineering: Metal Fatigue of Gas Compressor Components; Electrical Contact Evaluations; Cracking of Structural Plastics; Chemical Analysis; Corrosion & Stress Evaluation and Analysis; SEM Analysis; Electron/Optical Microscopy; X-ray Examination

Bison's clients argue their cases with confidence, secure in the knowledge that their claims are based on unbiased, scientific data.

Dr. Jeffrey Buckholz is a practicing design engineer with 30 years of experience in Traffic Engineering, Traffic Signal Timing, Signal Design and Signal Construction. He is also proficient in Pavement Marking Design, Roadway Signing, and Work Zone Traffic Control. Dr. Buckholz has authored 3 national training manuals in signal design, construction and inspection. He is a PE in 6 states: FL, GA, CA, MA, MI, OH and is a Professional Traffic Operations Engineer. Dr. Buckholz has been chief engineer of his engineering company for 20 years and has been an Adjunct Professor at the University of North Florida since 2005. He has served as an expert witness in about 50 cases.

Past Project Experience:

Traffic Studies

Traffic Signal and ITS Design

Traffic Signal Timing

Roadway Lighting

Signing and Pavement Marking Design

Work Zone Traffic Control Design

Dennis Wylie is an internationally recognized Human Factors Expert on driver error; inattention and improper lookout; driver fatigue; car, truck and bus driver skill and knowledge requirements; driver and motor carrier standards of care; hours of service violations; circadian rhythms; sleep debt; impaired vigilance, alertness, decision making, reaction time, and control responses.

Mr. Wylie directed the largest study of driver fatigue and alertness conducted in North America, a seven-year multimillion dollar international project that was the main factor in major revision of the federal and state rules governing working hours for commercial automobile, truck, and bus drivers, including an increase in required off-duty time of 25%.

Mr. Wylie and his colleagues also developed the national commercial driver licensing system. He is the principal author of the Commercial Driver's Manual used by all state licensing agencies for licensing commercial automobile, truck, and bus drivers. The information in the Commercial Driver's Manual defines the skill, knowledge and standard-of-care requirements for commercial drivers and is the basis of the commercial driver license (CDL) tests. Mr. Wylie and his colleagues trained the first CDL Examiners in each state, who went on to train the others. All commercial drivers in the United States – more than 20,000,000 so far – have been licensed under the CDL system, which is set out in the Code of Federal Regulations at 49 CFR 383 "Commercial Driver's License Standards."

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