168 research outputs found
Study of fuel systems for LH2-fueled subsonic transport aircraft, volume 2
For abstract, see N78-31085
Study of fuel systems for LH2-fueled subsonic transport aircraft, volume 1
Several engine concepts examined to determine a preferred design which most effectively exploits the characteristics of hydrogen fuel in aircraft tanks received major emphasis. Many candidate designs of tank structure and cryogenic insulation systems were evaluated. Designs of all major elements of the aircraft fuel system including pumps, lines, valves, regulators, and heat exchangers received attention. Selected designs of boost pumps to be mounted in the LH2 tanks, and of a high pressure pump to be mounted on the engine were defined. A final design of LH2-fueled transport aircraft was established which incorporates a preferred design of fuel system. That aircraft was then compared with a conventionally fueled counterpart designed to equivalent technology standards
NDE Characterization of Metallic Interfaces
In recent years, the process of diffusion bonding has found considerable usage in the aerospace and nuclear power industries [1]. This process entails two surfaces being pressed together at elevated temperatures and high pressures. If ideal conditions are achieved, the bonded interface will have properties identical to those of the matrix metal and the microstructure will be continuous across the interface. There is a fine margin for error in attaining ideal conditions and the ability to characterize the bond nondestructively is highly desirable. The present project is aimed at the development of ultrasonic techniques for the characterization of interfaces between two joined parts. The techniques that are being used have applicability to components joined by diffusion bonding, pinch welding, and friction bonding, and may also be useful in nondestructive measurements of rubbing friction and for bond strength
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J.S. Mill's re-conceptualization of liberty
In this dissertation, I argue that John Stuart Mill does not defend a
classical liberal, Lockean idea of liberty as freedom from coercion, especially
governmental coercion. Rather, I argue that Mill has something much more
radical in mind: for Mill, liberty requires freedom from the much broader idea of
“the moral coercion of public opinion.”
Mill’s so-called “harm principle,” which is at the root of his defense of
liberty, is often common-sensically interpreted according to what I term the
political interpretation of the harm principle. On the political interpretation the
harm principle is intended to restrict the use of coercion, especially governmental
coercion. On the political interpretation the harm principle is intended to draw a
line between those areas of life that are subject to moral sanctions, and those that
are subject to the law. All the mechanisms of moral suasion, including even boycotting, excommunication and shunning, are available to the moral realm; but
when one’s actions harm another, they become subject to legal punishment.
In contrast to the political interpretation, I urge an interpretation I call the
social interpretation of the harm principle. According to the social interpretation,
the harm principle is intended to restrict expressions of disapproval, such as
boycotting or blacklisting. According to the social interpretation, the harm
principle rules out any such notion as private morality/immorality: for something
to be considered immoral, it must harm others.Philosoph
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