Expertly Speaking

Justin Schorr

How Much of Your Personal Data is Stored by Infotainment Systems?


So, how much of your personal data is stored by infotainment systems and what is recoverable from them?

The investigators at 7 News Boston asked our engineers Robert Kinder, Jr., MS, and Justin P. Schorr, Ph.D., that same question. See the full story here, or contact Justin and Rob via email at or by phone at 215-659-2010, to learn more about our infotainment capabilities.

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retail stores

Why Reading the Safety Guide is Fundamental to Keeping Stores Accident Free

Jerry Birnbach, F.I.S.P., Retail Store Safety Consultant

Retailers produce important documentation such as employee handbooks, merchandising guides, and safety manuals to ensure all known, preventable accidents and issues are communicated to every employee hired to represent the brand. They are developed with care to clearly state procedures and protocols, should something arise as well as the types of safety issues to be on the lookout for. However, many stores continue to face safety-related lawsuits. Find out how “an ounce of prevention is worth a pound of cure” in the newsletter by Jerry Birnbach, F.I.S.P. – Why Reading the Safety Guide is Fundamental to Keeping Stores Accident Free

Jerry Birnbach, F.I.S.P., Retail Store Safety Consultant with DJS Associates, Inc., can be reached via email at or via phone at 215-659-2010.

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Child Seat Safety

Child Passenger Safety Week 2019

John R. Yannaccone, P.E., Senior Mechanical Engineer

September 15th to 21st is Child Passenger Safety Week, a time to make sure children are traveling safely. Every year, motor vehicle crashes rank high on the list of leading causes of injury and fatality for children in most age groups. Here are some points to consider:

  • Children over 4’9” are likely riding in a seatbelt. It is important to make sure the seatbelt fits them properly, as they are generally designed for adults. While there is no single criteria indicating when a child is large enough for a seatbelt without a booster or child’s car seat, there are steps you can take to determine when a child can rely solely on the seatbelt. (Is Your Child Big Enough to Ride in a Seatbelt)
  • If the child is smaller than 4’9”, they should be riding in a car seat. There are two important checks that should be made for safety. First, check the expiration date to confirm the child car seat is not past its allowed lifetime, which is typically 6 years. Second, verify the car seat has no open recalls. To do this you will need the car seat manufacturer, model number and date of manufacture. Checking for recalls can be done on either the manufacturer’s website or on the National Highway Traffic Safety Administration’s (NHTSA) website.
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Slip, SLIDE and Fall

Bryan J. Smith, P.E., Construction Site Safety/Slip, Trip and Fall Consultant

Case Description/Summary: While preparing for an annual festival, the plaintiff, a temporary employee of the property owner, was helping a frozen fish delivery person load the delivered products into an exterior walk-in cooler. The plaintiff loaded frozen fish boxes onto a cart and he intended to pull the cart up the cooler’s interior metal ramp so that he didn’t have to carry each individual box. He never looked down at the ramp floor before stepping upon it.

The plaintiff’s walking actions were not those of a normal pedestrian, just walking upon a flat, level surface. He was on a sloped ramp that was 8.3% sloped from the normal plane (a moderately slight incline from a horizontal plane). Under normal walking conditions, this slope would be considered shallow and far from being excessive – even for pedestrians with walking difficulties. The steeper a slope is, the more a pedestrian standing on it will have his weight (see black arrow in the illustration below) act to affect a slide down the ramp. This is because when weight is applied to a sloped surface, a portion of the weight vector will go “normal” (perpendicular – see yellow arrow) to the ramp’s surface. The remaining force vector of the weight would be applied parallel (see green arrow) to the sloped surface.

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Justin and Steve

The Reconstruction of a Legend

Justin P. Schorr, Ph.D., President, Principal Collision Reconstruction / Transportation Engineer

There are three parts to every collision: the vehicle, the roadway, and the driver. In honor of my father – and following the conceptual writing prompt he loved the most (“let’s see how far we can stretch this analogy”) – this article will take a look at the “great collision of life” and see how our framework applies. Yes, I could use this space, which we are grateful to have been awarded, to gloat about the recent “cease and desist” letter sent to Tesla (which I have been calling for the past 2 years), or to rewrite the ABC’s of the latest trend in crash reconstruction (another one of my father’s favorites). It may not be conventional – but there is no way I am going to pass up the opportunity to gloat about my father to such a distinguished audience.

The Vehicle. My old man was a machine. The vehicle which he drove on a daily basis was 5 foot 10 and 160 pounds – and this was true from the time he was in graduate school until the day he passed away. He used to tell me that he was under 5 feet tall when he graduated high school and then grew 8 inches between high school and college. I held out hope that the same would happen to me, but unfortunately, I am still waiting for 5’8” to turn into anything taller than 5’8”! Not only did his last moments come just after he dismounted his spin bike – but I will always remember the neon yellow runner’s pullover he had been wearing earlier that day. Dad was an athlete. Scratch that, he couldn’t hit a golf ball over 200 yards, and he had the worst wrist shot and slap shot I’ve ever seen. Dad loved to exercise. Much better. At 61 years old, his aerobic endurance was miles beyond my 33-year-old “vehicle,” and he had even completed a marathon (he had run a few) in under 4 hours.

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Surveillance Cameras: Inside Looking Out

Laurence R. Penn, Senior Forensic Animation/Video Specialist



There’s a good chance an interior surveillance camera located close to a window will capture activity or an incident outside of the property it is primarily intended to surveil. Such was the case when a surveillance camera observing the entrance of a store captured a collision where a right turning truck collided with a cyclist traveling the same direction on a narrow city street. In fact, there were many cameras that captured the incident, including three cameras from two different businesses and the dashcam on the truck itself.

Videogrammetry techniques were used to camera match one of the surveillance videos to high resolution 3D scan data of the site. The truck was also documented, and its 3D data used to re-create a trajectory as depicted in the surveillance video. Videogrammetry analysis of the other cameras helped confirm the results of the vehicle tracking.

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