Search Results

In developing a direct injection gasoline engine, the in-cylinder fuel air mixing is key to good performance and emissions. High speed visualization in an optically accessible single cylinder engine for direct injection gasoline engine applications is an effective tool to reveal the fuel spray pattern effect on mixture formation The fuel injectors in this study employ the unique multi-hole turbulence nozzles in a PFI-like (Port Fuel Injection) fuel system architecture specifically developed as a Low Pressure Direct Injection (LPDI) fuel injection system. In this study, three injector sprays with a narrow 40° spray angle, a 60°spray angle with 5°offset angle, and a wide 80° spray angle with 10° offset angle were evaluated. Image processing algorithms were developed to analyze the nature of in-cylinder fuel-air mixing and the extent of fuel spray impingement on the cylinder wall.

Challenges that persons with disabilities face with current modes of transportation have led to difficulties in carrying out everyday tasks, such as grocery shopping and going to doctors’ appointments. Autonomous vehicles have been proposed as a solution to overcome these challenges and make these everyday tasks more accessible. For these vehicles to be fully accessible, the infrastructure surrounding them need to be safe, easy to use, and intuitive for people with disabilities. Thus, the goal of this work was to analyze interview data from persons with disabilities, and their caregivers, to identify barriers to accessibility for current modes of transportation and ways to ameliorate them in pick up/drop off zones for autonomous vehicles. To do this, interview subjects were recruited from adaptive sports clubs, assistive living facilities, and other disability networks to discuss challenges with current public transit stops/stations.

Numerous studies have documented that lower extremity injury is second only to the head and face in automotive accidents. Such injuries are common because the lower extremity is typically the first point of contact between the occupant and the car interior. Of all lower extremity injuries, the knee is the most common site of trauma. This typically results from high speed contact with the instrument panel which can produce fracture and subfracture (contusions, lacerations, abrasions) level injuries. Current Federal safety guidelines use a bone fracture criterion which is based solely on a peak load. The criterion states that loads exceeding 10 kN will likely result in gross bone fracture. However, cadaver experiments have shown that increased contact area (via padding) over the knee can significantly increase the amount of load that can be tolerated before fracture or subfracture injury.

Injuries to the lower extremities are common during car accidents because the lower extremity is typically the first point of contact between the occupant and the car interior. While injuries to the knee, ankle and hip are usually not life threatening, they can represent a large societal burden through treatment costs, lost work days and a reduced quality of life. The aim of the current study was to specifically study injuries associated with the knee and to propose a methodology which could be used to prevent future knee injuries. To understand the scope of this problem, a study was designed to identify injury trends in car crashes for the years 1979-1995. The NASS (National Accident Sampling System) showed that 10% of all injuries were to the knee, second only to head and neck injuries. Most knee injuries resulted from knee-to-instrument panel contact. Subfracture injuries were most common (contusions, abrasions, lacerations) followed by gross fracture injuries.

Internet worms have shown the capability to compromise millions of network hosts in a matter of seconds, thereby precluding human countermeasures. A worm over a vehicular ad hoc network (VANET) can, in addition to the well-known threats, pose a whole new class of traffic-related threats (ranging from congestion to large-scale accidents). To combat these automated adversaries, security patches can be distributed by good worms. An accurate VANET-based worm propagation model is essential to protect from malicious worms and to efficiently utilize good worms for distribution of security patches. This paper derives an approximate closed-form mathematical model of worm propagation over VANETs. Simulation results assert that the proposed model captures the VANET worm propagation dynamics with outstanding accuracy.

This paper describes additional and more recent results from the DaimlerChrysler study of HANS that includes a sensitivity analysis of HANS performance to variations in crash dummy neck length and other impact test conditions. The objective of the tests was to determine the robustness of the HANS concept in a variety of conditions that might occur in actual use. The results show that the variations in test parameters do effect injury measures from the crash dummy, but HANS provides substantial reductions in injury potential in all cases compared to not using HANS. Also, no injuries were indicated with HANS.

This paper presents a review of the core functions and decisions of transportation and traffic management in the automobile industry. Its purpose is to present the concepts within a revised framework which is set in a logistical channels context. Using this approach it easier to see the interdependence which is necessary between shippers and carriers that handle raw materials, component parts, and finished products.

Injury to the lower extremity during an automotive crash is a significant problem. While the introduction of safety features (i.e. seat belts, air bags) has significantly reduced fatalities, lower extremity injury now occurs more frequently, probably for a variety of reasons. Lower extremity trauma is currently based on a bone fracture criterion derived from human cadaver impact experiments. These impact experiments, conducted in the 1960's and 70's, typically used a rigid impact interface to deliver a blunt insult to the 90° flexed knee. The resulting criterion states that 10 kN is the maximum load allowed at the knee during an automotive crash when certifying new automobiles using anthropomorphic dummies. However, clinical studies suggest that subfracture loading can cause osteochondral microdamage which can progress to a chronic and debilitating joint disease.