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New automotive trends for multiple fuel usage and low permeability are requiring new technical advancements as the traditional nitrile polymers fail to meet engineering demands. Data for nitrile polymers with acrylonitrile content in the 35% to 50% range have been developed with various fuels for various testing times. The improvement in fuel impermeability and fuel resistance at a very high acrylonitrile content is demonstrated. The ultra-high acrylonitrile polymer has been compared with hydrogenated nitrile. The thermal stability and the response to fuels and permeability of these two systems were investigated to establish the most economical engineering solution to meet automotive demands.

Radical processes are key reactions in the photodegradation of polymers. Electron Spin Resonance (ESR) provides a sensitive tool for measuring these paramagnetic substances. The ultrashort time weathering method developed at Bayer AG measures the concentration of radicals generated in a bulk polymeric sample as a function of irradiation time. In less than three hours, quantification of the number of radicals formed in a polymeric sample when exposed to a specific spectrum of light provides an assessment of the light stability or weatherability of the resin. Correlation studies (predicted ESR to real-time weathering) are underway. Evaluation of the type of radicals and their behavior as a function of temperature provides insight into the degradation mechanism. Addition of special radical-scavengers is not required with this method.

Armco's process for finishing a continuous hot-dip zinc coating on steel to achieve a surface finish comparable to that of cold-rolled steel is described. The process excludes oxygen from the jet nozzle finishing operation by enclosing the jet nozzles and strip within a chamber and supplying high purity nitrogen as the wiping media to the jet nozzles. After leaving the coating chamber, the strip passes through a steam mist which minimizes the spangle formation. All grades of ULTRASMOOTH are temper rolled to meet the surface texture requirements characteristic of automotive Class 1 cold rolled steel. The coated surface is free of ripples, dross and oxide patches. Coating uniformity is excellent. The spot welding characteristics are the same as other continuously hot-dip galvanized steels. The consistency and uniform reactivity of the coating surface results in even deposition of chemical pretreatments and uniform paint adherence.

The notion of a hybrid system is centered on a composition of discrete and continuous dynamics. Although the difficulty in modeling hybrid systems comes from the diversity of these systems, the most promising approach to mitigate this issue is developing expressive and precise modeling languages. Nevertheless, the developing of expressive and precise modeling languages does not necessarily mean the emergence of a new language, on the contrary, this paper proposes a precise semantics for a subset of existent languages. In this paper, we introduce hybrid fUML that blends synchronous features for controlling discrete behaviors, and differential algebraic equations (DAEs) into the standardized fUML (foundational subset for executable UML models). Synchronous features focused on discrete behaviors come from synchronous languages, which have been established as a technology of choice for specifying, modeling and verifying real-time systems, e.g., Lustre.

This paper discusses techniques developed and used by the Biosciences Group at the University of Michigan Transportation Research Institute (UMTRI) for measuring three-dimensional head motion, skull bone strain, epidural pressure, and internal brain motion of repressurized cadavers and Rhesus monkeys during head impact. In the experimental design, a stationary test subject is struck by a guided moving impactor of 10 kg (monkeys) and 25 or 65 kg (cadavers). The impactor striking surface is fitted with padding to vary the contact force-time characteristics. The experimental technique uses a nine-accelerometer system rigidly affixed to the skull to measure head motion, transducers placed at specific points below the skull to record epidural pressure, repressurization of both the vascular and cerebrospinal systems, and high-speed cineradiography (at 1000 frames per second) of radiopaque targets.

The use of two or three FID hydrocarbon analysers for the determination of condensable or liquid unburned fuel is described. Each FID has upstream pumps and filters in separate sample conditioning systems operating at three different temperatures of 180C, 50C and 2C. The 50C system could operate at any temperature up to 100C, the use of 50C was because this was the temperature used for sampling diesel particulates. The difference in the three hydrocarbon readings was used to determined on a mass basis the condensable UHC over the sample temperature difference of either 180C to 2C or 180C to 50C. The latter hydrocarbon difference was shown to be close to the particulate fuel fraction of the SOF. A range of applications of this technique to both diesel and spark ignition engines are described, including the warm-up of a Ford CVH SI engine and the influence of nozzle sac volume on condensable hydrocarbon emissions in a Perkins 4-236 diesel.

The author uses some analogies of mechanical things to illustrate the underlying facts that must be considered in connection with electrical ingition, the first being that of an automobile starting under the influence of a constant force, which is analogous mechanically to the old touch-spark ignition circuit in that the velocity of the automobile corresponds with the velocity or speed at which the electricity is moving through the circuit. In similar manner the analogy is extended to include car acceleration and its acquirement of a certain store of energy as an illustration of electrical-energy storage as the current through an induction-coil is increased; and further analogies are made, numerous diagrams being presented. Battery and magneto-ignition similarities are treated in a similar way, short and long sparks are discussed pro and con and spark lag is considered in general terms.

This work presents the first prototype of the zero emission vehicles (ZEV) program in development since 1992 in the Universidade Estadual de Campinas (State University of Campinas) - UNICAMP. This prototype is a electric-type vehicle, for urban utilization, based in the solar/ hydrogen/ electricity energy supply system, tractioned by lead-acid batteries and a motor-generator group adapted to hydrogen usage. The prototype technical characteristics (structure, components, etc.) and of performance (maximum speed, autonomy, etc.) are also presented.

Unikote is a one-side coated hot-dipped galvanized steel made by combination of conventional hot-dip galvanizing with a subsequent electrolytic operation. One surface of the product offers the corrosion resistance of galvanized steel while the other surface offers the appearance and paintability of cold rolled steel. Unikote is more easily welded than regular galvanized steel.

UNIPAC is a new two row tapered roller bearing assembly that has been developed for smaller automobiles that use an independent suspension, and front wheel drive. The new two row assembly offers a complete tapered roller bearing package that is pregreased, preadjusted and sealed. These unique functional characteristics are required of this bearing assembly for the independently sprung driving wheel position. Each functional bearing requirement has been studied and tested to assure satisfactory bearing performance at the most economical bearing price.

Developed by the U.S. National Highway Traffic Safety Administration, the National Advanced Driving Simulator (NADS) has many unique capabilities, including a large excursion envelope motion system with high performance. MTS Systems Corporation was responsible for the manufacture of the thirteen degree of freedom motion system driven by forty-five actuation channels. The motion system features a redundantly actuated ± 10 meter X and Y longitudinal and lateral steel belt drive for high stiffness and smoothness. A Stewart platform hexapod designed for taking advantage of the large X-Y travel rides on top the translation system. The hexapod supports a redundantly actuated ± 330-degree yaw turntable for more effective maneuver simulation and washout coordination. Finally, four high frequency vibration actuators beneath the cab feature self-reaction to minimize vibration to the graphics display dome and the projector support structure.

THE eventual solution to the question: “Shall it be of unit design or shall it have a separate frame?” will be known only when a complete understanding is reached of the ride problem, including car feel and quietness, and a better understanding is obtained of the structure's influence on these performance phases, Mr. Sherman believes. Such knowledge, he predicts, will result eventually in the lightest, least-expensive and best performing automobile, be it unitary in structure, conventional, or something as yet unconsidered. His paper brings out some of these considerations which have proved to be of paramount importance in research work conducted by his company. Pointing out that it is impossible to predict ahead of time just how a new car design will perform, he contends that it will be much easier to adjust the job to the best rigidity range with the separate-frame construction than with the unitary construction.

It is generally true that: - An airplane generates income only when it is flying, and - An increase in airplane utilization will tend to reap more profit for the operator. If airplane utilization can be increased without incurring a deterioration in schedule reliability or a prohibitively high increase in maintenance costs, such an increase in utilization is in the direction of optimization. This paper discusses the factors affecting utilization, particularly of cargo airplanes, and analyzes the effects of variations in elapsed-time allowed for maintenance and for loading (and refueling). The first section discusses the potential benefits to be derived by decreases in each of these variables, while the second section presents a status report on research and development work now in process, the goal of which is to increase airplane utilization through decreasing the ground time for loading and unloading.