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From page 26... ... speeds equal to an OC-3 (45 Mbps, approximately 30 times that of a T-1 connection) ; • A dedicated climate control system with a backup contingency system;26• Remote monitoring alarm system for indication of fire, smoke, intrusion, power outage, climate control failure, hardware failure, water presence, and high temperature; • Elevated flooring system; • High physical security with steel-reinforced structural walls; • Limited personnel accessibility; and • Two 600-ft2 secure data reduction laboratories that house high-end Dell workstations. Read the entire page →
From page 27... ... This system allows researchers and data reductionists to work directly with large databases while providing ease of use and improved accuracy. As shown in Figure 4.3, reductionists can select specific variables and customize the interface of the illustration. Read the entire page →
From page 28... ... Two servers hosted UMTRI data when it was first collected in 2004 through 2005. The first server is a Dell PowerEdge 4600 with a 12-GB system drive, a 546-GB RAID 10 drive containing database data files, and a 124-GB RAID 1 drive containing database log files. Read the entire page →
From page 29... ... If any portion of the road, including turn lanes, were covered in snow, the classification was snow covered. The traffic density was coded using the number of visible traffic counts in the front camera, as shown in Figure 4.5 (1) Read the entire page →
From page 30... ... Specifically, the DAS captured a 5-s video clip every 5 min from the face camera, regardless of the driving situations or driver activity, creating a random sample of driver activity. The triggers (RDCWS alerts generated by the LDWS, CSWS, or a driver comment button pressed by the driver) Read the entire page →
From page 31... ... Data Collected in Project 5 Data Sources Vehicle and driver identifications Vehicle position, heading, and motion: speed, yaw rate, accelerations, pitch and roll angle and rates, GPS (differential and nondifferential) Driver control inputs: steering wheel angle, throttle input, brake switch, turn signal, headlamp state, cruise control state and set speeds, LDWS and CSWS sensitivity settings RDCWS driver displays: LDWS and CSWS alerts and levels, availability icons RDCWS intermediate values: lane position, warning thresholds, road geometry estimates, threat locations, vehicle-centered object map Roadway environment: road type and attributes, urban and rural settings RDCWS and subsystem health and diagnostics information, as well as subsystem version numbers RDCWS radar data: forward radar data, side radar data Video: forward driving scene and driver face views Audio from driver comment button: dictated messages from driver Preset values CAN bus and FOT sensors CAN bus CAN bus CAN bus Onboard digital map via CAN bus, plus postprocessing, Highway Performance Monitoring System (HPMS) Read the entire page →
From page 32... ... ." Crash-relevant events were "any circumstance that requires a crash avoidance response on the part of the subject vehicle or any other vehicle, pedestrian, cyclist, or animal that is less severe than a rapid evasive maneuver, but greater in severity than a ‘normal maneuver' to avoid a crash. A crash avoidance response can include braking, steering, accelerating, or any combination of control inputs.The severities of the valid events were determined based on various criteria, and all required variables were recorded and edited in MySQL databases. Read the entire page →
From page 33... ... The variables are described in Table 4.4.Table 4.4. List of Variables in Reduced Data in Project 6 Classification List of Variables General information Event variables Contributing factors Environmental factors: driving environment Driving environment: infrastructure Driver state variable Driver/Vehicle 2 Vehicle number, epoch number, event severity, trigger type, driver subject number, onset of precipitating factor, and resolution of the event Event nature, incident type, pre-event maneuver, judgment of Vehicle 1 maneuver before event, precipitating factor, evasive maneuver, and vehicle control after corrective action Driver behavior: Driver 1 actions and factors relating to the event, Driver 1 physical or mental impairment, Driver 1 distracted, willful behavior, driver proficiency, Driver 1 drowsiness rating, Driver 1 vision obscured by, and vehicle contributing factors Weather, light, windshield wiper activation, surface condition, and traffic density (level of service) Read the entire page →
From page 34... ... The crashes and near crashes were parsed into the following 18 conflict categories: • Conflict with a lead vehicle; • Conflict with a following vehicle; • Conflict with oncoming traffic; • Conflict with a vehicle in an adjacent lane; • Conflict with a merging vehicle; • Conflict with a vehicle turning across the subject vehicle path in the same direction; • Conflict with a vehicle turning across the subject vehicle path in the opposite direction; • Conflict with a vehicle turning into the subject vehicle path in the same direction; • Conflict with a vehicle turning into the subject vehicle path in the opposite direction;• Conflict with a vehicle moving across the subject vehicle path through the intersection; • Conflict with a parked vehicle; • Conflict with a pedestrian; • Conflict with a pedal cyclist; • Conflict with an animal; • Conflict with an obstacle or object in the roadway; • Single-vehicle conflict; • Other (specify) ; and • Unknown conflict. Read the entire page →
From page 35... ... are classified as any circumstance that requires a rapid, evasive maneuver, including steering, braking, accelerating, or any combination of control inputs that approaches the limits of the vehicle capabilities, by the subject vehicle or any other vehicle, pedestrian, cyclist, or animal to avoid a crash. Near crashes (no evasive maneuver) Read the entire page →
From page 36... ... After data reduction, 915 safety-relevant events were identified; of these, there were 14 crashes, 14 tire strikes, 98 near crashes, and 789 crash-relevant conflicts. A random sample of 1,072 baseline epochs was also selected to represent normal driving. Read the entire page →
From page 37... ... of % of No. of % of Crashes: Crashes: Near Near Traffic Density Crashes Crashes Tire Strikes Tire Strikes Crashes Crashes LOS A 13 92.9% 9 64.3% 61 62.2% LOS B 1 7.1% 1 7.1% 21 21.4% LOS C 0 0.0% 4 28.6% 11 11.2% LOS D 0 0.0% 0 0.0% 1 1.0% LOS E 0 0.0% 0 0.0% 2 2.0% LOS F 0 0.0% 0 0.0% 2 2.0% Unknown 0 0.0% 0 0.0% 0 0.0% Total 14 100.0% 14 100.0% 98 100.0%Weather conditions were coded as "No adverse conditions," "Rain," "Sleet," "Snow," "Fog," "Rain and fog," "Sleet and fog," "Other," and "Unknown." Table 4.8 shows the numbers and percentages of crashes, crashes: tire strikes, and near crashes associated with each weather condition.Table 4.8. Read the entire page →
From page 38... ... For example, heavy traffic occurs in 10% of the baseline epochs but is present in 20% of the event epochs. Although 20% is not a high percentage, it is a factor worthy to note.Project 11: Naturalistic Teen Driving Study Data reduction procedures in this study included three tasks: initial data reduction, straight road segment data reduction, and event data reduction. Read the entire page →
From page 39... ... of % of No. of % of Crashes: Crashes: Near Near Traffic LOS Crashes Crashes Tire Strikes Tire Strikes Crashes Crashes LOS A 3 60.0% 4 50% 23 37.7% LOS B 2 40.0% 3 37.5% 22 36.1% LOS C 0 0.0% 0 0.0% 13 21.3% LOS D 0 0.0% 0 0.0% 1 1.6% LOS E 0 0.0% 1 12.5% 2 3.3% LOS F 0 0.0% 0 0.0% 0 0.0% Unknown 0 0.0% 0 0.0% 0 0.0% Total 5 100.0% 8 100.0% 61 100.0%Table 4.12. Read the entire page →
From page 40... ... A crash is defined as "any contact with an object, either moving or fixed, at any speed in which kinetic energy is measurably transferred or dissipated. Includes other vehicles, roadside barriers, objects on or off the roadway, pedestrians, cyclists, or animals." A near crash is defined as "any circumstance that requires a rapid evasive maneuver by the subject vehicle or any other vehicle, pedestrian, cyclist, or animal to avoid a crash. Read the entire page →
From page 41... ... 2. University of Michigan Transportation Research Institute. Read the entire page →

From page 26...

... speeds equal to an OC-3 (45 Mbps, approximately 30 times that of a T-1 connection) ; • A dedicated climate control system with a backup contingency system;26• Remote monitoring alarm system for indication of fire, smoke, intrusion, power outage, climate control failure, hardware failure, water presence, and high temperature; • Elevated flooring system; • High physical security with steel-reinforced structural walls; • Limited personnel accessibility; and • Two 600-ft2 secure data reduction laboratories that house high-end Dell workstations.