7,906 research outputs found
Approach to the assessment of the hazard
An overview of the carbon fiber hazard assessment is presented. The potential risk to the civil sector associated with the accidental release of carbon fibers from aircraft having composite structures was assessed along with the need for protection of civil aircraft from carbon fibers
Perspective on the results
The results of studies on the risk due to the use of carbon fibers in aircraft are assessed. Assumptions such as additional fire protection in the aircraft, new structural concepts, and the development of unique carbon composites are evaluated. Some findings from the national risk profile including equipment vulnerability and economic impact are discussed
Risk analysis approach
The assessment of the carbon fiber hazard is outlined. Program objectives, requirements of the risk analysis, and elements associated with the physical phenomena of the accidental release are described
Carbon Fiber Risk Analysis: Conclusions
It was concluded that preliminary estimates indicate that the public risk due to accidental release of carbon fiber from air transport aircraft is small. It was also concluded that further work is required to increase confidence in these estimates
A basis for the analysis of surface geometry of spiral bevel gears
Geometrical procedures helpful in the fundamental studies of the surface geometry of spiral bevel gears are summarized. These procedures are based upon: (1) fundamental gear geometry and kinematics as exposited by Buckingham, et al; (2) formulas developed from differential geometry; and (3) geometrical concepts developed in recent papers and reports on spiral bevel gear surface geometry. Procedures which characterize the geometry so that the surface parametric equations, the principal radii of curvature, and the meshing kinematics are systematically determined are emphasized. Initially, the focus in on theoretical, logarithmic spiral bevel gears as defined by Buckingham. The gears, however, are difficult to fabricate and are sometimes considered to be too straight. Circular-cut spiral bevel gears are an alternative to this. Surface characteristics of crown circular cut gears are analyzed
Surface geometry of circular cut spiral bevel gears
The tooth surface principal radii of curvature of crown (flat) gears were determined. Specific results are presented for involute, straight, and hyperbolic cutter profiles. It is shown that the geometry of circular cut spiral bevel gears is somewhat simpler than a theoretical logarithmic spiral bevel gear
A wind-tunnel and analytical study of the conversion from wing lift to rotor lift on a composite-lift V/TOL aircraft
Wind tunnel and analytical study of conversion from wing lift to rotor lift on composite lift VTOL aircraf
Ideal spiral bevel gears: A new approach to surface geometry
The fundamental geometrical characteristics of spiral bevel gear tooth surfaces are discussed. The parametric representation of an ideal spiral bevel tooth is developed based on the elements of involute geometry, differential geometry, and fundamental gearing kinematics. A foundation is provided for the study of nonideal gears and the effects of deviations from ideal geometry on the contact stresses, lubrication, wear, fatigue life, and gearing kinematics
Summary of Working Group I: Hadron Structure
A summary is given on the main aspects which were discussed by the working
group. They include new results on the deep inelastic scattering structure
functions and and their parametrizations, the
measurement of the gluon density, recent theoretical work on the small
behavior of structure functions, theoretical and experimental results on
, the direct photon cross section, and a discussion of the event
rates in the high range at Tevatron and the high range at HERA, as
well as possible interpretations.Comment: 22 pages latex, including 8 figures (ps,eps), to appear in the
Proceedings of the International Conference on Deep Inelastic Scattering,
Chicago, April 1997, AI
Tooth profile analysiis of circular-cut, spiral-bevel gears
An analysis of tooth profile changes in the transverse plane of circular-cut, spiral-bevel crown gears is presented. The analysis assumes a straight-line profile in the mid-transverse plane. The profile variation along the centerline is determined by using expressions for the variation of the spiral angle along the tooth centerline, together with the profile description at the mid-transverse plane. It is shown that the tooth surface is a hyperboloid and that significant variations in the pressure angle are possible
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