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A simple method of weighting emissions data to provide a relation between source mass emissions and the resulting impact on air pollution is proposed. The importance of the following factors are considered: chemical severity of the pollutant species, source effectiveness, population exposure, and area severity. The selection of these factors is described with particular attention to the obtaining of chemical severity factors from air quality standards. Qualifications upon the use of this weighting scheme are outlined. Application to the Los Angeles and San Francisco bay areas show that weighted emissions of transportation sources are less than their mass emissions, while weighted emissions of all other pollutant sources are greater than their mass emissions. In both cases, transportation remains the dominant pollution source category.

The presently used laboratory hypoid gear scoring tests are described and the deficiencies are noted. The inadequacies of these tests led to the development of a test device and a procedure designed to evaluate gear lubricants more accurately. An account of the development of the test system with the cooperation of the Coordinating Research Council, Inc. (CRC) is given. The unique design features of the gearbox and the test gears are described. An account is given of the steps in the test development and the use of the CRC reference oils in this development. The test is capable of evaluating the scoring resistance of hypoid gear oils covering a range of performance levels from RGO 104 to RGO 110. Data on repeatability are presented.

A testing technique has been evolved using typical United States and European production multicylinder gasoline engines to assess the effect of quantity and type of lubricant ash on surface ignition. Results indicate that, for a given metal type of additive, high-ash lubricants have a greater propensity to surface ignition than corresponding low-ash blends. Tests at a constant ash level show magnesium-based lubricants to be less prone to such problems than barium- or calcium-based lubricants.

The cold pumpability characteristics of a group of commercial premium crankcase oils were evaluated at 0 and -20 F in a test stand engine. A test procedure was developed for these evaluations which gave results that compared favorably with those obtained in two popular makes of test cars at 0 F. In a second, more detailed, phase of this study, the effects of fourteen factors on the cold pumpability of several crankcase oils were investigated. The data from both phases were then analyzed to determine if an oil's cold pumpability in an engine could be predicted from its CCS viscosity, Brookfield viscosity, GM pour time, or ASTM pour point.

Tests were conducted throughout the temperature range of -65-0 F with a truck axle equipped with observation windows and temperature-measuring equipment. Twenty-one test lubricants encompassing a wide range of physical properties were employed in the investigation. Based upon this study, the flow characteristics of satisfactory sub-zero gear lubricants have been identified. Correlations of the truck axle flow results with several commonly specified tests for fluidity were attempted and discussed. The development of a small axle flow simulator is described, and its correlations with full-scale axle flow results are discussed.

The performance characteristics of a naturally aspirated two-cycle engine can be predicted with an unsteady gas dynamics analysis of flow through the crankcase and cylinder; such an analysis provides values of volumetric efficiency and trapping pressure at any given engine speed. The predictions of the volumetric efficiency and trapping pressure are compared with experimental values from a high-specific-output engine and further amplified with theoretical/experimental comparisons of pressure-time histories taken in the exhaust, transfer, and inlet systems at several engine speeds. The theoretical derivation of unsteady gas dynamic cylinder to pipe boundary conditions is presented so that they become both economical of computer time and mathematically stable.

Maximum temperature is a critical parameter in the control of any thermodynamic cycle. Fast and precise temperature control means improved specific fuel consumption and increased engine life by making it possible to maintain the engine at or near its maximum temperature, yet not exceeding it. The fluidic temperature sensor is the first direct measuring sensor that offers both long life and fast response. It is applicable to mass production techniques and is ideally suited to vehicular and commercial gas turbine usage, as well as other types of heat engines.

A market existed in the 2-cycle engine field for an internal combustion engine in the 1-1/2 to 2-1/2 in3 displacement range for the original equipment manufacturer. The engine had to be lightweight, compact, low in manufacturing costs, and yet offer high power output and continuous operation. For this market, O & R Engines, Inc. designed the 2-CID Model 20 engine. The design filled a further requirement of the OEM by providing the flexibility of component design and arrangement. This paper discusses these design aspects.

A computer program has been developed which predicts the sound pressure level and the frequency spectrum produced by simple engine exhaust systems. The program utilizes unsteady flow gas dynamic theory to predict the pressure-time history in the exhaust system and the velocity-time history at the open end of the system. Acoustic theory is then used to predict the sound pressure levels and frequency spectrum in free space. The work was carried out on a twin-cylinder four-cycle engine, but the theory can be applied to any internal combustion engine.

This paper presents the results of a study to determine the factors required to monitor visual range. Equations are presented that indicate that it is possible to monitor visual range by using measurements of scene luminance, atmospheric backscatter, and ambient light levels. The concept of a device that could monitor a driver's visual range using these measurements is also described.

Instrumentation has been developed to track and record dynamically an automobile driver's voluntary and involuntary eye motions with no encumbrance to the driver's head or eye. This portable eye-tracking system makes possible field studies of the driver's: 1. angle of gaze referenced to the scene. 2. involuntary eye motions as possible indications of physiological state (fatigue, intoxication, etc.). 3. pupil response.

This was an investigation of the relationship between heart rate variability (HRV) and driver performance, and a preliminary test of an Experimental Alertness Indicator (EAI)- a device for measuring HRV. Three drivers drove on a round-the-clock basis for 5 days over a 364 mile (586 km) circuit on a California highway. HRV and driver error frequency were recorded and analyzed to determine effects of driving time, rest breaks, traffic event frequency, and other variables. The results showed that HRV increased markedly with driving time, HRV recovered after rest, HRV might have reflected features of the highway's geometric configuration, HRV dropped substantially after the occurrence of events which realerted the drivers, and HRV was little influenced by traffic event frequency per se. It was concluded that HRV is related to driver alertness/fatigue and that the EAI has promise of being useful for estimating the level of driver alertness.

A new two-speed winch of the traction-drum, storage-drum type for underground or overhead cable installation. Hydraulically driven with efficient planetary and spur-gear reductions, it is capable of levelwinding great lengths of wire or nonconducting rope under heavy-load condition. With uniform input torque and speed, it will exert a constant cable pull and speed throughout any length of pull. It will free-spool for rapid rope removal. It is equipped with an indicating load gage, is fully adjustable for maximum cable pull and of a size compact enough to fit within a utility truck body.

This paper discusses the value and the need for the simulation of relevant driver information processing and control functions. The emphasis is on relevance of simulation to ensure that such a simulation would have the practical utility of helping to reduce some accidents. An overall review is given of accident rate study findings, results of manual control studies, and conclusions based on psychomotor performance skills research. From this review, it can be pointed out that most people who drive a car, even as they are learning to drive, already know how to operate each of the various controls and switches and pedals found in a car. However, the sequence in which these should be operated, and the conditions under which they are operated are the critical factors to be learned and overlearned.

A new winch system has been developed and tested for installation of underground, or overhead, power or communication lines. The system utilizes a hydraulically powered traction winch with emphasis on ease of rope threading on a pair of urethane-coated grooved pulling drums. Engagement force for traction is provided by a separate hydraulically powered storage winch with a hydraulic powered levelwind. The load, speed, and footage are monitored continually. Control, reliability, and ease of maintenance have been the prime objectives throughout this project. Separate components add to the flexibility of the system and permit tailoring of each application.

A new curemeter, called Cone-Rheometer, has been developed. This instrument simultaneously determines changes in pressure and stiffness in elastomeric compounds during the course of vulcanization. The use of the Cone-Rheometer to evaluate extruded, continuously vulcanized, neoprene and EPDM sponge stocks is described. The effects of changes in blowing agent level, blowing agent type, and test temperature are observed and discussed.

Semirigid urethane-foam specimens of various high densities were evaluated when subjected to simulated heavy-mass impacts such as in low-speed automobile collisions. The dynamic test results showed excellent material-energy absorption with essentially no compression sets, even after many repeated impacts of high deflection. These findings, coupled together with the well-known tough physical properties of urethanes, provide an outstanding candidate material that can be used to effectively reduce the damage to support structures and contact surfaces, not only in automotive applications but in any other application requiring a reduction of shock forces.

A new method for determining the spring and damping constants for elastomer materials is presented. The method relies on three concepts-measurement of force and displacement or velocity across the test specimen, precise control of differential phase shift and sensitivity in transducers and electronics over the full operating frequency and amplitude range, and automatic optimal identification of K and C using analog hardware. The technique may be used in conjunction with either a resonant beam or electrohydraulic system, as demonstrated in the paper. Typical error sources are presented for both systems with indications given of their elimination by the new technique. Hardware implementing the concepts is described and calibration test results given. It is concluded that the system provides an automatic test procedure which has the potential to reduce errors and maintain consistent results for rubber properties, relatively independent of the test machines and operators.

Comfort, styling, and durability of automotive seating is largely due to the excellent performance of flexible urethane foam cushioning elements. This paper reviews the production and properties of current molded urethane foam cushioning, and the total assembly seating performance requirements. The newer developments of “full-depth” cushioning and “high-resilience” foams are examined in some detail.

Driver response and performance can be quantified by observing the stimulus-response environment. Yet the driver's inherent adaptability allows him to have seemingly adequate performance in potentially hazardous driving situations even though he may be operating near the acceptable safety limits. Physiological measures of the driver's internal state can provide further quantification of his performance level and can give a measure of his workload or safety performance margin. Measures of driver physiological and control responses have been made under gust disturbance conditions with the subject's car operating at various speeds. The experimental techniques and data are described, and correlations between the situational parameters and driver stress and control response are shown.