Excited states in the full QCD hadron spectrum on a 163×4016^3 \times 40 lattice

We report the hadron mass spectrum obtained on a $16^3 \times 40$ lattice at $\beta = 5.7$ using two flavors of staggered fermions with $m a = 0.01$. We calculate the masses of excited states that have the same quantum numbers as the $\pi$, $\rho$ and $N$. They are obtained by a combined analysis of the hadron correlators from sources of size $16^3$ and $8^3$. We also report on the hadron spectrum for a wide range of valence quark masses.Comment: Contribution to Lattice 95. 4 pages. Compressed, uuencoded postscript file. Send questions to [email protected]

Observer-Based Controller Design for Systems on Manifolds in Euclidean Space

A method of designing observers and observer-based tracking controllers is proposed for nonlinear systems on manifolds via embedding into Euclidean space and transversal stabilization. Given a system on a manifold, we first embed the manifold and the system into Euclidean space and extend the system dynamics to the ambient Euclidean space in such a way that the manifold becomes an invariant attractor of the extended system, thus securing the transversal stability of the manifold in the extended dynamics. After the embedding, we design state observers and observer-based controllers for the extended system in one single global coordinate system in the ambient Euclidean space, and then restrict them to the original state-space manifold to produce observers and observer-based controllers for the original system on the manifold. This procedure has the merit that any existing control method that has been developed in Euclidean space can be applied globally to systems defined on nonlinear manifolds, thus making nonlinear controller design on manifolds easier. The detail of the method is demonstrated on the fully actuated rigid body system.Comment: SICE Annual Conference, Nara, Japan, September, 201

Some sufficient conditions for infinite collisions of simple random walks on a wedge comb

In this paper, we give some sufficient conditions for the infinite collisions of independent simple random walks on a wedge comb with profile \{f(n), n\in \ZZ\}. One interesting result is that if $f(n)$ has a growth order as $n\log n$, then two independent simple random walks on the wedge comb will collide infinitely many times. Another is that if \{f(n); n\in \ZZ\} are given by i.i.d. non-negative random variables with finite mean, then for almost all wedge comb with such profile, three independent simple random walks on it will collide infinitely many times

Innovations and Experiments in Uses of Health Manpower—The Effect of Licensure Laws

Time-resolved optical spin orientation is employed to study spin dynamics of I * and I-1* excitons bound to isoelectronic centers in bulk ZnO. It is found that spin orientation at the exciton ground state can be generated using resonant excitation via a higher lying exciton state located at about 4 meV from the ground state. Based on the performed rate equation analysis of the measured spin dynamics, characteristic times of subsequent hole, electron, and direct exciton spin flips in the exciton ground state are determined as being tau(s)(h) = 0.4 ns, tau(s)(e) greater than= 15 ns, and tau(s)(eh) greater than= 15 ns, respectively. This relatively slow spin relaxation of the isoelectronic bound excitons is attributed to combined effects of (i) weak e-h exchange interaction, (ii) restriction of the exciton movement due to its binding at the isoelectronic center, and (iii) suppressed spin-orbit coupling for the tightly bound hole