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Viewing 164041 to 164070 of 183200
1967-02-01
Technical Paper
670666
E. P. Trott
There are many problems encountered in taking a mechanized mathematical/logic model from the concept and “toy” problem stage to the production capability stage. The problems encountered in developing the production capability of the MARCEP technique are indicative of the types of problems that can be expected for any large program of this type. The problem areas can be classified as Program Logic Problems and Computer Limitation Problems. Program Logic Problems include describing basic system components to ensure logical results, forcing the computer to select redundant configurations which have been predetermined as necessary, establishing a rationale for investigating crew survival and mission success, and methods of handling components with short wear lives.
1967-02-01
Technical Paper
670664
Vernon L. Grose
Reliability and maintainability of both terrestrial and space systems have too long been needlessly sacrificed because man's role within each system has been an afterthought. To overcome this short-sighted approach, man's capabilities as well as limitations must be clearly understood at the outset of system development by those who are responsible for design. This paper presents the results of recent research in human engineering which should aid system designers to optimize man's role as a control element in space systems. In particular, five human characteristics necessary for spacecraft control are shown to exceed the capabilities of any known or planned machines. The maximum role of which man is capable should be defined for each particular space system. When this maximum role is known, then tradeoffs become possible between human and automatic control.
1967-02-01
Technical Paper
670670
A. Hevesh
Phased planar array radars represent a class of equipment employing hundreds or thousands of individually steerable radiating and receiving elements. In the operation of such systems, it is necessary to keep continually ahead of an advancing failure accumulation through maintenance policies geared to replacement-while-in-operation concepts. Several practical maintenance polices are considered: Immediate maintenance Delayed maintenance Cyclic maintenance The effects of these policies on the outage availability are considered and it is shown that each has certain advantages. Immediate maintenance yields the highest system availability, but requires the continued presence of a moderate size maintenance force. Increasing the number of maintenance crews increases the availability of phased array systems, but the added contribution to satisfactory system states shrinks rapidly with the growth of crews.
1967-02-01
Technical Paper
670672
John E. Snyder
An idealized approach to developing design criteria for a ground support system, assessing the system effectiveness, and improving system design is described. System design starts with mission objectives and performance requirements. As the flight system is designed the assembly, test, and checkout functions are identified. These generate requirements to be satisfied by the ground system. Requirements are allocated to the system elements as design criteria and provide the basis for ground system design and procurement. The system is designed and fabricated to these criteria. Since typical space programs include a very limited number of space vehicles of high cost and complexity, it is important to assess and ensure system performance before the hardware is operational. Computer simulation of system operation, including reliability and maintainability, provides a system effectiveness prediction and identifies soft spots so that early remedial action is possible.
1967-02-01
Technical Paper
670668
Rex B. Gordon
A FUNDAMENTAL ASPECT of the System Safety Engineering concept which requires attention and improvement is that of defining the more subtle safety requirements of a complex system. It is suggested that safety requirements must be presented in measurable terms and expressions if they are to be consistantly and effectively incorporated in design.
1967-02-01
Technical Paper
670812
J. G. Hayes
The parameters of time, temperature, and turbulence affect the efficiency of incinerators in the control of organic solvent emissions from stationary equipment. Fuel costs are a problem, however, on which more data are needed. For example, for a large incinerator with no heat recovery features, the installed cost may be as low as $1.75/cfm for a 23,000 cfm unit with a fuel cost as low as $23/hr. A small unit without heat recovery but using no external combustion air might cost $11/cfm. The cost of equipment and operation is directly proportional to the exhaust volume to be handled.
1967-02-01
Technical Paper
670808
Louis J. Fuller
Aside from emissions from motor vehicles, organic solvents were the last remaining major hydrocarbon contribution to photochemical smog in Los Angeles County. Rule 66 was formulated to control these organic solvent emissions.
1967-02-01
Technical Paper
670813
H. E. Sipple
The Los Angeles Air Pollution Control District Rule 66 restricts the emission of photochemically reactive organic solvents to the atmosphere. The rule has affected more segments of industry in Los Angeles County than any one of the many preceeding air pollution rules, because organic solvents are used in nearly all manufacturing establishments. Solvent suppliers are making a major effort to develop suitable exempt material for unrestricted use. This paper reviews trends in the development of nonphotochemically reactive solvents. Prototype examples are given of some of the new materials now commercially available.
1967-02-01
Technical Paper
670807
Warren M. Dorn
The part Rule 66 plays in total air pollution control in Los Angeles County is explained. Background material on the control of visible emissions, sulfur, hydrocarbons, and motor vehicle emissions is presented. Finally, the background and acceptance of Rule 66 is described.
1967-02-01
Technical Paper
670810
Robert G. Lunche
Compliance with Los Angeles County solvent control legislation can be achieved by treatment of the organic emissions resulting from solvent usage, converting to less photochemically reactive solvents, or changing the process. An engineering permit system and an enforcement inspection program ensure that control equipment to treat the effluent is designed for the required efficiency and operated in compliance with the law.
1967-02-01
Technical Paper
670809
Walter J. Hamming
The need for an appraisal of the potential contribution of organic solvent usage to the photochemical smog problem in Los Angeles County had gradually become apparent and was confirmed by the results of surveys to determine the kinds and quantities of solvents used. The need for control of emissions resulting from various uses of organic solvents could be determined only by investigation and evaluation of the relative photochemical reactivity of such emissions The studies and criteria utilized to assess both such needs are described as well as the sresults of the studies into a functional, purposeful rule for the control of organic solvent emissions.
1967-02-01
Technical Paper
670804
S. E. Ingels, W. H. Kinney
The deformation and mechanical joining of beryllium and beryllium-aluminum alloys is discussed with respect to a typical aerospace structure utilizing normal cross-rolled sheet, characterized by a maximum BeO content of 2.0% ingot sheet rolled directly from high purity cast billets, and 62% beryllium-SS'Yo aluminum alloy. Selection and application of material types is determined on the basis of mechanical properties, manufacturing considerations, and availability. Surface imperfections induced by manufacturing procedures are shown to be greatly reduced or eliminated by proper stress relief and etching. Examples of simple unidirectional bends and complex forming, requiring severe multidirectional material flow, are given. Mechanical joints resulting in net tension values equal to the yield strength of the beryllium are shown to be possible with proper choice of fasteners and joint geometry.
1967-02-01
Technical Paper
670803
G. Raymond Paul
Familiarity with beryllium metal machining and handling characteristics places the material in favorable perspective with conventional materials. The stability, coefficient of expansion, and thermal conductivity of beryllium are very favorable to achieving and maintaining size control. Extensive use in the aerospace industry has assisted in development of allied processes that further enhance the achievements in fabrication techniques. This paper shows the evolution of fabrication considerations from procurement through completion of parts. Interim processes and surface treatments will be discussed, featuring some applications.
1967-02-01
Technical Paper
670806
S. Smith Griswold
1967-02-01
Technical Paper
670750
R. J. Boyd, C. L. Nalezny
A lumped parameter model consisting of a spring and coulomb friction is developed to simulate soil cutting by a plow blade vibrating horizontally. The spring represents blade and soil elasticity; the coulomb friction represents soil strength. Predicted instantaneous and average forces agree favorably with those obtained experimentally for a sinusoidally vibrating blade in a compacted silty sand. Results indicate that, for a given cutting speed, average force can be reduced by increasing frequency, displacement amplitude, and/or system stiffness. For practical design values of these parameters, the force can be reduced to 25% of the nonvibrating cutting force. Further reductions can be achieved only by large increases in the parameters.
1967-02-01
Technical Paper
670805
George D. Cremer, James R. Woodward, Larry A. Grant
New developments in braze-joining are presented. This technology will extend practical utilization of beryllium in fabrication of lightweight, exceptionally stiff components. Consideration of structural beryllium brazements is discussed. Some examples are monocoque cylindrical and conical shapes, radiator assemblies, sheet metal brackets, and sandwich structures. Beryllium exhibits attractive properties up to 1200 F. Special fabrication techniques are necessary, however, due to its metallurgical and mechanical peculiarities. Data presented show the effect of filler metal interactions on stress levels attainable in properly brazed joints. Beryllium is extremely versatile and is an unparalleled material of construction where strength/weight at elevated temperature is the criterion.
1967-02-01
Technical Paper
670749
A. G. Bodine
A new earth working technique has been developed as an outgrowth of experiments in sonic power transmission, whereby a tool combination having an elastic resonance is set against the resistance of earthen material, much as an electronic power circuit deals with its load. An essential element in this, for accomplishment of maximum performance, is the provision of a unique type of mechanical oscillator which automatically uses “feedback” from the resonator. Use of circuit concepts in the design of sonic equipment results in very simple, reliable, and rugged mechanisms. Typical ones are applied in earthmoving machinery. These design concepts also have a surprising degree of operational simplicity.
1967-02-01
Technical Paper
670802
Don L. Hedges
The toxic properties of beryllium have been known for many years. New developments in the fields of industrial hygiene and manufacturing have greatly reduced the hazard in fabrication of beryllium components. These new methods of control have also reduced the cost of process control. This paper describes the techniques used by North American Rockwell to control the toxic effects of fabricating beryllium. Also discussed are the medical controls.
1967-02-01
Technical Paper
670751
E. T. Selig
Full scale field tests on soil compaction were undertaken to evaluate the effectiveness of various methods of achieving compaction and to examine techniques for compaction control. The test variables included type of soil, moisture content, lift thickness, type of compactor, compactive effort, and number of roller coverages. Vibratory, pneumatic, segmented pad, and sheepsfoot rollers were investigated. Measurements of soil strength and density were made after a prescribed number of roller coverages. A comparison of results between the vibratory method and the other methods was made to provide insight into the role of vibration in compaction. The basic concepts of vibratory compaction are also discussed.
1967-02-01
Technical Paper
670833
J. D. Boulgarides, V. C. San Filippo
This paper defines and discusses technical obsolescence of engineers and scientists. It is concerned with the knowledge explosion in general terms, and in specific areas. The impacting force of the knowledge explosion is considered in terms of organizations and individuals. An approach to assessing the impact of the knowledge explosion is proposed. The responsibility for positive action to avoid technical obsolescence is discussed. The scope of this paper is restricted to the technical obsolescence of engineers and scientists, and does not concern itself with equipment and facilities.
1967-02-01
Technical Paper
670834
C. Wilson Whitston
The interfaces of engineering and management offer an insight into why the engineer, when viewed as in his castle, avoiding constraints, seems out of contact with the facts of business life. His sharing in the benefits and yields, while shunning a full measure of responsibility, appears less than glamourous in final, depersonalized analysis. A view of the engineer as manager, judicious scheduler, and user of resources after regressive analysis of professional antecedents and future expectations; the engineer as participant, delineator, and communicator; as active in the art and science of management as well as in design, innovation, and research, can be projected as faces of an attainable value, with enhanced professional esteem.
1967-02-01
Technical Paper
670828
Richard K. Bowler
The examination of ground transportation conditions at the Los Angeles International Airport (LAX) suggests that while there is still some potential street and freeway capacity left, future problems may arise. Ground transportation limitations require that means must be found either to decentralize departing flights or bring arriving passengers to the airport by other means. The Department of Airports proposes a system of satellite airports and metroports, utilizing flying buses or VTOL/STOL aircraft to transport passengers around the metroport area. To be successful, the system should provide a flat rate fare for all passengers, regardless of their airport destination.
1967-02-01
Technical Paper
670830
Norman E. Nelson
A new type of rotary wing aircraft, the compound aircraft, is currently in development for the armed services. This new method of VTOL flight appears to offer great promise to the commercial VTOL field, particularly as it applies to the interurban mass transportation problem. It has been apparent for some years that fixed wing aircraft, due to airport congestion both in the air and on the ground, cannot fill this requirement. The possibilities of this new type of aircraft in this environment are discussed.
1967-02-01
Technical Paper
670832
E. R. Moyes
Negotiated price of a defense contract indicates the quality/risk level at which engineering must perform. This article describes a method for controlling engineering to the proper quality to insure a profit. It includes a discussion of engineering task breakdown, task cost estimating, scheduling, and status reporting.
1967-02-01
Technical Paper
670732
H. L. Krewson
This paper discusses filtration of the primary air for a gas turbine used as a vehicle prime mover. The design criteria are developed and presented, and physical filter construction and mounting are described. From results presented, it is concluded that inlet air filtration for mobile gas turbines is practical.
1967-02-01
Technical Paper
670731
Barrett G. Rich, O. A. Smith, Lee Korte
The evolution of a formal reliability program, the organization and function of all departments in the reliability division, and some associated accomplishments to date are presented. The total program is discussed, including reliability goal setting, analysis of new and current design, inspection planning, reconciliation of engineering specifications and manufacturing processes, vendor rating, and audit and inspection procedures. Emphasis is placed on proved successful procedures.
1967-02-01
Technical Paper
670729
William R. Gostlin, Frank S. Payerle
Improved and increasingly complex farm, construction and industrial machinery demand improved remote control systems. This paper focuses on one element of the mechanical remote control system which is keeping pace with the industry, the push-pull control cable. Recent improvements in material and construction features of push-pull cables make their use in an ever-increasing variety of applications more attractive from the standpoints of cost, ease of installation, durability, and reliability.
1967-02-01
Technical Paper
670730
Russ Henke
1967-02-01
Technical Paper
670728
R. A. Burt, John P. Connolly
A concept for combining the separate manual controls of a multiaxis system was explored and demonstrated on a Ford backhoe. The four axes of the backhoe system receive their command signal from a single 4 degree-of-freedom controller. The motion of the backhoe then “mimics” that of the controller, generating a followup signal to close the control loop. This control system provides simultaneous, coordinated control of all four axes in response to natural movements of the human operator.
1967-02-01
Technical Paper
670727
Donald J. Fergle
A 300 hp, four speed, forward and reverse, power shifting test box has been designed, fabricated, and tested by the Eaton Yale & Towne Research Center at a rated input speed of 30,000 rpm. The concept incorporates a torque limiting clutch on the input shaft to limit inertia shock loads during shifting, and unique expanding sleeve clutches for changing gear ratios. Expanding clutch material and design were developed through extensive bench testing and computer investigation. A 30,000 rpm high pressure, controlled leakage rotating seal was developed for the input shaft. Limited experience with the vehicle installation is also discussed.

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