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The systems approach to transportation planning has proven itself to be sound and effective. To accommodate itself to today's values, however, the planning process must be broadened so that it considers community impacts as fully as economic impacts. While current legislation and regulations mandate such an approach, additional research and data gathering are required to allow the full evaluation of community impacts. Transportation planning must conceive of strategies other than constructing new facilities. These include economic and land development policies and low capital intensive alternatives. More citizen participation and better intergovernmental decision-making on a metropolitan-wide basis are required if urban transportation plans are to gain public support and if their timely implementation is to be realized.

Development of the U.S. Army's 1500-shp advanced technology demonstrator engines was initiated in 1967. Presented are several lessons of a technical and nontechnical nature learned from the program. Several problem areas encountered are highlighted and analyzed. Reflected is the need for standardization within the industry of methods of bookkeeping component efficiencies and of conducting engine performance analysis. Scheduling, development approach, and instrumentation experiences and requirements are also discussed.

To date new transportation systems have failed to avoid the impact of noise on the surrounding community, due to lack of adequate planning in terms of depth of research and analysis, lack of attention to the whole problem of noise pollution, and the lack of coordinated planning of communities and the transport system that serve them. This paper discusses several ways to achieve greater coordination between community planning and transportation planning in order to reduce noise. A systems approach should include the steps of identification of objectives, identification of programs, prediction of effectiveness, and evaluation of alternatives. Several means of doing this are discussed.

Natural science information can be used to more sensitively locate major urbanization components such as new communities and major components of the national transportation system, such as airports. The public decision-maker needs this information displayed in a systematic, usable form so that the consequences of all alternative choices are apparent prior to the final decision. The integration of the natural sciences, evolving operations research techniques and community development tools appear to offer a procedure for producing this vital planning ingredient.

This paper reviews research done by the Systems Research Group at The Ohio State University on the information-seeking behavior of automobile drivers. The effect of sleep deprivation, long-term driving, and low levels of alcohol intoxication on driver eye-movement patterns is discussed. The adaptive behavior which results from loss of peripheral information processing capability under stress is manifested through wider dispersion and less preview by the tired drivers and tunnel vision by the intoxicated drivers. The loss of this information can be expected to result in unsafe performance.

This study explores the application of viscoelastic modeling for characterization of the response of the brain to impulsive loading with the objective of learning whether such models could exhibit the same time dependency of strain or likelihood of injury, as exhibited by the Severity Index, HIC Index, Wayne Tolerance Curve, and other similar representations of tolerance. The mathematical relationships between viscoelastic properties and the corresponding time dependency of tolerance are shown for Newtonian, Bingham plastic, and Pseudo-Bingham, as well as more general behavior. Preliminary static and dynamic tests upon small mammalian material are described with particular attention given to strain in the vicinity of the brainstem as a function of loading profile. Both the theoretical and experimental results show that the falling time dependency of the above indexes can be interpreted in terms of nonlinear viscoelastic response.

A new laboratory test facility for measuring the various understeer influences on complete vehicles is described. The machine actuates the body and suspension in the same manner as it occurs on the road while turning or braking. Changes in steer and camber angles of the wheels are measured as body roll, tire lateral forces, and tire aligning torques are applied to the vehicle separately or simultaneously. It makes a direct measurement of vehicle roll susceptibility (tendency to roll in a turn). Steer caused by braking, called brake steer, is measured by applying brake forces. A description is given of the systems and interacting subsystems of the machine, which provide duplication of a wide range of actual over-the-road conditions while preventing application of unrealistic constraints to the vehicle. Design features that create the capability to obtain the desired accuracies while minimizing test time are also discussed.

The response of material to interfacial friction and abrasive slippage is discussed. Friction is divided into two factors: viscoelastic and adhesive. With slippage, the adhesive factor results ultimately in abrasion. Abrasion has been studied in the laboratory from a mechanistic approach and in the field from a base material approach. At least two mechanisms have been found: a tensile failure and a fatigue oxidative failure. Three major components of the tread (carbon black, oil, and polymer) have been found to have the largest influence on friction and wear. Some properties of carbon black and polymers that have been related to wear are reviewed.

Operating characteristics of a single-cylinder, spark-ignition engine fueled by both methanol and isooctane were determined. Engine output, indicated specific fuel consumption, and specific emissions of hydrocarbon, carbon monoxide, nitric oxide, and aldehydes were measured for both fuels and compared using performance maps. The engine output comparisons showed that lean misfire limits occurred at leaner mixtures with methanol than with isooctane and that maximum engine output levels were nearly equal for both fuels. Comparison of the specific parameters of each fuel at equivalent power levels obtained with maximum power spark timing permits the following conclusions: Use of methanol results in higher indicated specific fuel consumption, greater emission of aldehydes, but lower emissions of hydrocarbon and nitric oxide; the two fuels showed similar trends of carbon monoxide emission.

The problem of aerodynamic and rolling resistance characteristics of cars and trucks is of considerable importance to vehicle engineers as the two major contributions to external vehicle drag. Many testing methods have been developed including wind tunnel testing of scale models, testing of full-size production cars, and coast-down testing. The advantages and disadvantages of each method are discussed and analyzed.

The dynamic responses of the human skull and facial bones have been determined by a series of impact experiments. A preliminary report was issued on this subject with particular reference to three impact sites of the skull-the frontal, temporo-parietal, and zygomatic. This work has been extended to include more experiments in these areas to delineate further the nature and reliability of the earlier data. In addition, new data have been obtained for the maxilla, mandible, and zygomatic arch in order to include additional anatomic sites that are frequently involved in accidental impacts. Relationships to impulse duration, peak force, and various anatomic characteristics have been studied and will also be presented. Additional data have been obtained for unembalmed anatomic specimens to provide new information to supplement and expand the tolerance base reported in the preliminary study.

The effective fit concept for involute splines, as documented in the American National Standard B92.1-1970, is described. The flexibility of the concept is demonstrated, and examples in both English and metric (SI) units of measure are given. The paper reflects the latest (1970) revision to the B92.1 standard, which was developed in the '40s and first published under the designation B5.15.

A test bed electric vehicle was developed to provide a most favorable operating environment for state-of-the-art lead-acid storage batteries. Performance data were acquired using portions of SAE J227, Electric Vehicle Test Procedure. Test results illustrate the performance potentials for special purpose road vehicles designed around this power source.

The need for balancing a high-speed rotor in a manner that accounts for its speed-dependent deformations is discussed. The influence coefficient method of flexible rotor balancing is described with reference to the balancing of an advanced gas turbine engine rotor. This engine rotor-bearing system is then studied in detail as an application of flexible rotor balancing, using the influence coefficient method. The relative effectiveness of various combinations of balance speeds and numbers of balance planes is compared.

A new clad metal system has been developed as a material for hydraulic brake line tubing. The material consists of a 1008 LCS/304 SS/1008 LCS composite in the ratio 45%/10%/45%. Laboratory experimental tests, accelerated life tests, and field tests were performed on brake tubing formed from this material. The results show that the brazed and ternecoat low-carbon steel/stainless steel/low-carbon steel tubing has excellent corrosion resistance and high mechanical strength. The results are compared with those obtained with conventional brazed and ternecoat LCS brake tubing.

This paper presents conclusions of a study of rollover collisions and the injuries resulting from them. The injury severity, the type of injury, the body region injured, the frequency of injury, and the injury mechanism are all indicated. The study includes statistics on both restrained and unrestrained occupants, and shows that ejected occupants usually sustain more severe injury than contained occupants. Several conclusions are presented as to automobile structures in relation to injury.

A new Jaguar engine, incorporating 12 cylinders in 60 deg Vee formation and using aluminum for most of its construction, was announced in conjunction with a new “E”-type, Series “3” sports car in March 1971. This paper is intended to describe this engine and to discuss some of the more interesting design features. The background history of the previous XK engine is presented, together with the reasons for designing the new engine. The design features single camshafts per cylinder bank, with valves in line in a flat combustion chamber, together with a new Lucas transistorized ignition system. A technical specification, together with relevant illustrations, is contained in the Appendixes.

Acceleration-time data in 25 squirrel monkeys subjected to controlled sagittal plane head motions are presented. In 12 of the 25 animals subjected to pure translation of the head at peak positive g levels ranging between 665-1230 g (6-8 ms duration), cerebral concussion was not obtainable. In contrast, 13 of the animals subjected to head rotations at peak positive tangential (at c.g.) g levels ranging between 348-1025 g (5.5-8 ms duration) were all concussed. Visible brain lesions were noted in both translated and rotated groups but with a greater frequency and severity after rotation. An analysis of the lesions produced in both groups is presented, along with our preliminary data on the use of the evoked somatosensory response as an objective, quantifiable index for the onset and severity of brain damage in head injury.

The BP-399-T and other engines of this family were planned as snowmobile and ATV engines with particular regard to balancing. They show shaking forces of 14-30% of those of conventional designs. Engine balance becomes a major factor, wherein vibrational forces should be considered in two classes: those which are symmetrical about the c.g. and cause translations of the c.g. through space, and those forces which are unsymmetrical and cause the body to rotate or rock. The mechanics of design and development are discussed, along with installation problems.