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Privatisation Methods and Economic Growth in Transition Economies
In low-income countries privatization, if implemented appropriately, may play an
important role in generating growth. Using data recently available from Central and
Eastern Europe, we therefore investigate the impact of alternative methods of
privatization on economic growth. Our analysis suggests that the use of conventional
privatization methods to match owners with firms can be inefficient in economies
with underdeveloped capital markets, particularly if wealth is poorly correlated with
managerial and entrepreneurial ability. In these circumstances mass privatization,
with firms being given away or sold at a nominal price, may be the appropriate policy
choice
Constructing N-qubit entanglement monotones from anti-linear operators
We present a method to construct entanglement measures for pure states of
multipartite qubit systems. The key element of our approach is an antilinear
operator that we call {\em comb} in reference to the {\em hairy-ball theorem}.
For qubits (or spin 1/2) the combs are automatically invariant under
SL(2,\CC). This implies that the {\em filters} obtained from the combs are
entanglement monotones by construction. We give alternative formulae for the
concurrence and the 3-tangle as expectation values of certain antilinear
operators. As an application we discuss inequivalent types of genuine
four-qubit entanglement.Comment: 5 pages, revtex4; more detailed illustration of the metho
Hydrogen-methane fuel control systems for turbojet engines
Design, development, and test of a fuel conditioning and control system utilizing liquid methane (natural gas) and liquid hydrogen fuels for operation of a J85 jet engine were performed. The experimental program evaluated the stability and response of an engine fuel control employing liquid pumping of cryogenic fuels, gasification of the fuels at supercritical pressure, and gaseous metering and control. Acceptably stable and responsive control of the engine was demonstrated throughout the sea level power range for liquid gas fuel and up to 88 percent engine speed using liquid hydrogen fuel
Hadronic light-by-light scattering contribution to the muon anomalous magnetic moment revisited
We discuss hadronic light-by-light scattering contribution to the muon
anomalous magnetic moment a_\mu^{\rm lbl}, paying particular attention to the
consistent matching between the short- and the long-distance behavior of the
light-by-light scattering amplitude. We argue that the short-distance QCD
imposes strong constraints on this amplitude overlooked in previous analyses.
We find that accounting for these constraints leads to approximately 50 per
cent increase in the central value of a_\mu^{\rm lbl}, compared to existing
estimates. The hadronic light-by-light scattering contribution becomes
a_\mu^{\rm lbl}=136(25) \times 10^{-11}, thereby shifting the Standard Model
prediction closer to the experimental value.Comment: 16 pages, 2 figure
Propeller propulsion integration, phase 1
A bibliography was compiled of all readily available sources of propeller analytical and experimental studies conducted during the 1930 through 1960 period. A propeller test stand was developed for the measurement of thrust and torque characteristics of full scale general aviation propellers and installed in the LaRC 30 x 60 foot full scale wind tunnel. A tunnel entry was made during the January through February 1980 period. Several propellers were tested, but unforseen difficulties with the shaft thrust torque balance severely degraded the data quality
Computer program offers new method for constructing periodic orbits in nonlinear dynamical systems
Computer program uses an iterative method to construct precisely periodic orbits which dynamically approximate solutions that converge to precise dynamical solutions in the limit of the sequence. The method used is a modification of the generalized Newton-Raphson algorithm used in analyzing two point boundary problems
Control means for a gas turbine engine
A means is provided for developing a signal representative of the actual compressor casing temperature, a second signal representative of compressor inlet gas temperature, and a third signal representative of compressor speed. Another means is provided for receiving the gas temperature and compressor speed signals and developing a schedule output signal which is a representative of a reference casing temperature at which a predetermined compressor blade stabilized clearance is provided. A means is also provided for comparing the actual compressor casing temperature signal and the reference casing temperature signal and developing a clearance control system representative of the difference. The clearance control signal is coupled to a control valve which controls a flow of air to the compressor casing to control the clearance between the compressor blades and the compressor casing. The clearance control signal can be modified to accommodate transient characteristics. Other embodiments are disclosed
Method for constructing periodic orbits in nonlinear dynamic systems
Method is modification of generalized Newton-Ralphson algorithm for analyzing two-point boundary problems. It constructs sequence of solutions that converge to precise dynamic solution in the sequence limit. Program calculates periodic orbits in either circular or elliptical restricted three-body problems
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