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28
Explicit design of timevarying stabilizing control laws for a class of controllable systems without drift
 Systems and Control Letters
, 1992
"... This paper gives a systematic way to design timevariant feedback control laws for a class of controllable nonlinear systems. This class contains a lot of systems which cannot be stabilized via a timeinvariant feedback control law. The interest of this work lies in the design method since a genera ..."
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Cited by 89 (2 self)
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This paper gives a systematic way to design timevariant feedback control laws for a class of controllable nonlinear systems. This class contains a lot of systems which cannot be stabilized via a timeinvariant feedback control law. The interest of this work lies in the design method since a general existence result is already available. The techniques employed here are basic: they mainly involve classical Lyapunov analysis.
PseudoRandom Functions and Factoring
 Proc. 32nd ACM Symp. on Theory of Computing
, 2000
"... The computational hardness of factoring integers is the most established assumption on which cryptographic primitives are based. This work presents an efficient construction of pseudorandom functions whose security is based on the intractability of factoring. In particular, we are able to constru ..."
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Cited by 13 (2 self)
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The computational hardness of factoring integers is the most established assumption on which cryptographic primitives are based. This work presents an efficient construction of pseudorandom functions whose security is based on the intractability of factoring. In particular, we are able to construct efficient lengthpreserving pseudorandom functions where each evaluation requires only a (small) constant number of modular multiplications per output bit. This is substantially more efficient than any previous construction of pseudorandom functions based on factoring, and matches (up to a constant factor) the efficiency of the best known factoringbased pseudorandom bit generators.
Perfect Matchings Extend to Hamilton Cycles in Hypercubes
"... Kreweras’ conjecture [1] asserts that any perfect matching of the hypercube Qd, d ≥ 2, can be extended to a Hamilton cycle. We prove this conjecture. ..."
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Cited by 10 (1 self)
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Kreweras’ conjecture [1] asserts that any perfect matching of the hypercube Qd, d ≥ 2, can be extended to a Hamilton cycle. We prove this conjecture.
Bhadeshia: ‘Mechanical stabilisation of austenite
 Mater. Sci. Technol
"... A theory has been developed for the mechanical stabilisation of plastically deformed austenite by balancing the force which drives the transformation interface against the resistance from dislocation debris in the austenite. The work has been used to explain why very large strains are required to me ..."
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Cited by 8 (4 self)
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A theory has been developed for the mechanical stabilisation of plastically deformed austenite by balancing the force which drives the transformation interface against the resistance from dislocation debris in the austenite. The work has been used to explain why very large strains are required to mechanically stabilise certain stainless steels, and also to interpret the subunit mechanism of bainite growth.
Matching graphs of Hypercubes and Complete bipartite graphs
"... Kreweras’ conjecture [9] asserts that every perfect matching of the hypercube Qd can be extended to a Hamiltonian cycle of Qd. We [5] proved this conjecture but here we present a simplified proof. The matching graph M(G) of a graph G has a vertex set of all perfect matchings of G, with two vertices ..."
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Cited by 2 (1 self)
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Kreweras’ conjecture [9] asserts that every perfect matching of the hypercube Qd can be extended to a Hamiltonian cycle of Qd. We [5] proved this conjecture but here we present a simplified proof. The matching graph M(G) of a graph G has a vertex set of all perfect matchings of G, with two vertices being adjacent whenever the union of the corresponding perfect matchings forms a Hamiltonian cycle of G. We show that the matching graph M(Kn,n) of a complete bipartite graph is bipartite if and only if n is even or n = 1. We prove that M(Kn,n) is connected for n even and M(Kn,n) has two components for n odd, n ≥ 3. We also compute distances between perfect matchings in M(Kn,n).
The CSL Collapse Model and Spontaneous Radiation: An Update
, 1998
"... A brief review is given of the continuous spontaneous localization (CSL) model, in which a classical field interacts with quantized particles to cause dynamical wavefunction collapse. One of the model’s predictions is that particles ``spontaneously’’ gain energy at a slow rate. When applied to the e ..."
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Cited by 1 (1 self)
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A brief review is given of the continuous spontaneous localization (CSL) model, in which a classical field interacts with quantized particles to cause dynamical wavefunction collapse. One of the model’s predictions is that particles ``spontaneously’’ gain energy at a slow rate. When applied to the excitation of a nucleon in a Ge nucleus, it is shown how a limit on the relative collapse rates of neutron and proton can be obtained, and a rough estimate is made from data. When applied to the spontaneous excitation of 1s electrons in Ge, by a more detailed analysis of more accurate data than given previously, an updated limit is obtained on the relative collapse rates of the electron and proton, suggesting that the coupling of the field to electrons and nucleons is mass proportional. 1.
A/D Graphs  A Data Structure For Data Dependence Analysis In Programs With Pointers
"... This paper describes A/D graphsa new structure to determine data dependences in programs with pointers. In contrast to known methods, with A/D graphs we can derive the data dependences of a program statement by a single corresponding graph. Our method uses storage more efficiently and can handle ..."
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Cited by 1 (1 self)
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This paper describes A/D graphsa new structure to determine data dependences in programs with pointers. In contrast to known methods, with A/D graphs we can derive the data dependences of a program statement by a single corresponding graph. Our method uses storage more efficiently and can handle the modules of a program separately. With A/D graphs we can perform a data dependence analysis by solving a monotone data flow system for restricted imperative languages. Based on an intraprocedural analysis using A/D graphs which produce optimal results we developed a method to derive a safe approximation of the data dependences by employing kbounded A/D graphs. Using this method we can perform intraprocedural as well as interprocedural data dependence analysis with storage quadratic in the number of program statements. The use of A/D graphs for data dependence analysis promises a significant improvement over known methods. Though we have constructed an experimental system to obtain preliminary data on the usefulness of our method, we still lack a sound comparison of the results to that of other systems. Currently we are working toward an integration of A/D graphs into the SUIF [1] system. As a further step we are attempting to extend the present research to programs with arbitrary, and in particular recursive, data structures. Our final aim is to be able to analyze any imperative program that does not use pointer arithmetic. Acknowledgements
Power Spectrum Independent Constraints on Cosmological Models †
, 1993
"... A formalism is presented that allows cosmological experiments to be tested for consistency, and allows a simple frequentist interpretation of the resulting significance levels. As an example of an application, this formalism is used to place constraints on bulk flows of galaxies using the results of ..."
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A formalism is presented that allows cosmological experiments to be tested for consistency, and allows a simple frequentist interpretation of the resulting significance levels. As an example of an application, this formalism is used to place constraints on bulk flows of galaxies using the results of the microwave background anisotropy experiments COBE and SP91, and a few simplifying approximations about the experimental window functions. It is found that if taken at face value, with the quoted errors, the recent detection by Lauer and Postman of a bulk flow of 689 km/s on scales of 150h −1 Mpc is inconsistent with SP91 at a 95 % confidence level within the framework of a Cold Dark Matter (CDM) model. The same consistency test is also used to place constraints that are completely modelindependent, in the sense that they hold for any power spectrum whatsoever — the only assumption being that the random fields are Gaussian. It is shown that the resulting infinitedimensional optimization problem reduces to a set of coupled nonlinear equations that can readily be solved numerically. Applying this technique to the abovementioned example, we find that the Lauer and Postman result is inconsistent with SP91 even if no assumptions whatsoever are made about the power spectrum. Submitted to Ap. J. in November 1993, revised in December 1993.
A SelfConsistent Dynamical Model for the COBE Detected Galactic Bar
, 1995
"... A 3D steady state stellar dynamical model for the Galactic bar is constructed with 485 orbit building blocks using an extension of Schwarzschild technique. The weights of the orbits are assigned using the nonnegative least square method. The model fits the density profile of the COBE light distribu ..."
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A 3D steady state stellar dynamical model for the Galactic bar is constructed with 485 orbit building blocks using an extension of Schwarzschild technique. The weights of the orbits are assigned using the nonnegative least square method. The model fits the density profile of the COBE light distribution, the observed solid body stellar rotation curve, the falloff of minor axis velocity dispersion and the velocity ellipsoid at Baade’s window. We show that the model is stable. Maps and tables of observable velocity moments are made for easy comparisons with observation. The model can also be used to set up equilibrium initial conditions for Nbody simulations to study stability. The technique used here can be applied to interpret high quality velocity data of external bulges/bars and galactic nuclei.
Have mirror planets been observed?
, 1999
"... Over the last few years, several close orbiting ( ∼ 0.05 AU) large mass planets (M ∼ MJupiter) of nearby stars have been discovered. Their existence has been inferred from tiny doppler shifts in the light from the star. We suggest that these planets may be made of mirror matter. We also point out th ..."
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Over the last few years, several close orbiting ( ∼ 0.05 AU) large mass planets (M ∼ MJupiter) of nearby stars have been discovered. Their existence has been inferred from tiny doppler shifts in the light from the star. We suggest that these planets may be made of mirror matter. We also point out that some stars such as our sun may also have a similar amount of mirror matter, which has escaped detection due to the effects of a tiny force such as photon mirror photon kinetic mixing or something else.