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Tests are carried out to assess the potential of using SCR DeNOx catalysis, for achieving ultra-low NOx emission levels with heavy-duty diesel engines. A prototype DeNOx catalyst system has been developed which consists of a moderately sized SCR catalyst, upstream of which urea is injected through a heat-shielded nozzle. Downstream of the SCR catalyst a low sulphate oxidation catalyst is used to ensure any ammonia slippage from the SCR stage is oxidized. The system was tested on a standard 2-valve EURO 2 engine over several steady-state and transient test cycles currently under discussion for European use. Over these test cycles NOx emission values of about 2 to 2.5 g/kWh are accomplished, which are sufficient to fulfill future European heavy-duty NOx emissions legislation to be expected around the year 2005.

A very promising use of fiber optics in trucks and buses is the utilization of a cab-mounted plastic optical fiber imaging device as a viewing system for the purpose of enhancing a vehicle's safe operation by minimizing blind spots. This device uses a coherent fiber-optic bundle and lenses to deliver live color images from outside the vehicle to an interior monitor allowing the driver to see the blind spot areas. The advantages over other technologies is that a plastic optical fiber system is a passive device that does not require: power, electronics, controls, or any moving parts.

This study examines the combined effects of the passenger airbag and the seat belt on the occupant impact response. It was found that while an airbag is beneficial in reducing unbelted occupant injury, its restraint force is in general additive to that of the belts in a 30 MPH barrier impact and tends to increase belted occupant response numbers. A number of possible design strategies were discussed and the inherent performance trade-offs among various impact conditions were illustrated. Concepts for two types of Adaptive Restraint System (ARS) are discussed which might achieve even greater levels of occupant protection for both belted and unbelted occupants. For a belted occupant, these ARS designs have embedded logic to determine when and how to use an airbag and/or a belt under various impact conditions. These ARS designs try to utilize the combined strengths of the airbag and the seat belt systems. Possible design strategies for these systems were also discussed.

This Aerospace Standard (AS) establishes the requirements for Heat Treating Accreditation by the National Aerospace and Defense Contractors Accreditation Program (NADCAP). These requirements may be supplemented by additional requirements specified by the NADCAP Heat Treating Task Group. Using the audit checklist (AC7102) will ensure that accredited heat treat suppliers meet all of the requirements in this standard and all applicable supplementary standards. All instructions, procedures, tests and inspection records, etc., referenced herein shall be in writing; distribution of instructions and procedures (including all revisions) shall be recorded and controlled. The NADCAP Heat Treating Task Group recognizes SAE AS7004, SAE AS7106, and SAE AS7107 as equivalent to the systems questions of this document as noted in the NADCAP Auditor Handbook.

Spherical convex auxiliary mirrors are commonly used on commercial vehicles to expand the field of view (FOV) beyond the limited FOV (approximately 10 degrees lefl and 4 degrees right) available in flat mirrors commonly referred to as “West Coast Mirrors”. Unfortunately the tradeoff with the short radius spherical convex mirrors used to obtain the desired FOV is a dramatic reduction (95% or greater) in apparent image size. This much reduced image size provides the vehicle operator with information sufficient to detect the presence or absence of adjacent vehicles, but is of limited use in making the relative speed and relative distance judgements required for lane changes. Considerable efforts are being expended to develop relatively high cost electronics based object detection and warning systems.

This specification covers an aluminum alloy in the form of honeycomb core in a non-hexagonal, flexible cell configuration, the core being treated for increased corrosion resistance and furnished only in the expanded form.

Development of a state of the art facility specifically designed for accelerated endurance testing (AET) of heavy trucks has been completed. The 1 km road features Belgian block, broken concrete, ruts, potholes, sine sweeps, S turns, a turning pad, a curbing event and a frame torsion event. In keeping with modern trends to streamline product development the facility is adjacent to the company's Technical Center and Prototyping facility creating a central, full capability development center. The roughness profiles of the random road surfaces were developed by relative damage calculations using theory of random vibration to establish the proper acceleration factor. A broad range of operating conditions may be simulated by varying speed and event mix. An absolute correlation of the track to other test facilities and field conditions in the USA, Mexico and Canada has been made using a vehicle equipped with 18 transducers. Over 20,000 km of road data has been included in this effort.

At the Naval BioDynamics Laboratory (NBDL) in New Orleans a large series of human volunteer experiments has been conducted by Ewing and Thomas [1]* to determine the dynamic head-neck response. From a number of these experiments Wismans et al. [2] determined omni-directional dummy head-neck performance requirements relative to a non-rotated T1 coordinate system (i.e. the head motions incorporate the influence of the thoracic column flexibility). In 1987, the frontal volunteer head-neck response was compared with the response of postmortem human subject (PMHS) experiments [3]. One of the findings was that the volunteer T1 rotations differ significantly from the PMHS T1 rotations which was explained by measurement “errors” in the T1 instrumentation. The present paper is an extension of the previous work [2,3]. A detailed analysis of the high-speed films revealed that the volunteer T1 instrumentation mount was not firmly mounted to the spine.

This specification covers an aluminum alloy in the form of plate.

A second series of low speed rear end crash tests with seven volunteer test subjects have delineated human head/neck dynamics for velocity changes up to 10.9 kph (6.8 mph). Angular and linear sensor data from biteblock arrays were used to compute acceleration resultants for multiple points on the head's sagittal plane. By combining these acceleration fields with film based instantaneous rotation centers, translational and rotational accelerations were defined to form a sequential acceleration history for points on the head. Our findings suggest a mechanism to explain why cervical motion beyond the test subjects' measured voluntary range of motion was never observed in any of a total of 28 human test exposures. Probable “whiplash” injury mechanisms are discussed.

Alloy: L-605 UNS Number: R30605

The sensitivity of biomechanical models to parameter estimation errors is crucial in determining the reliability of the dynamic estimates provided by these models. For evaluating the risk of head and neck injury from indirect impact (inertial loading), the forces and torques at key anatomical locations are important dynamic quantities. For human volunteers, these variables are estimated using head/neck models incorporating measured kinematic time traces and several indirectly measured mechanical and geometric parameters (e.g., the head center of gravity). In this paper, the sensitivity of estimated forces and torques at the occipital condyles to variations in head/neck geometric and mechanical properties, initial head positioning, and input kinematics is illustrated using a single fixed link model. Using anthropometric X-ray and fitted inertial response data from human volunteers, these forces and torques are estimated for two standard geometric/mechanical datasets.

This specification covers a low-alloy steel in the form of welding wire.

This specification covers a solvent-free cleaner in the form of an aqueous-base liquid concentrate or a ready-to-use liquid.

This specification covers an aluminum alloy in the form of clad sheet.