Chermakani, Deepak Ponvel


Abstract
We convert, within polynomial-time and sequential processing, NP-Complete Problemsinto a problem of deciding feasibility of a given system S of linear equations with constants and coefficients of binary-variables that are 0, 1, or -1. S is feasible, if and only if, the NP-Completeproblem has a feasible solution. We show separate polynomial-time conversions to S, from the SUBSET-SUM and 3-SAT problems, both of which are NP-Complete. The number of equations and variables in S is bounded by a polynomial function of the size of the NP-Completeproblem, showing that deciding the feasibility of S is strongly-NP-Complete. Wealsoshow how to apply the approach used for the SUBSET-SUM problemtodecidethe feasibility of Integer Linear Programs, as it involves reducing the coefficient-magnitudes of variables to the logarithm of their initial values, though the number of variables and equations are increased. 


Yiyang Gong

Abstract
Quantum Cellular Automata (QCA) is a feasible method of manipulating a system of qubits carrying quantum information, as the same operations are applied to the entire system. With the proper initial conditions and boundaries for a two dimensional lattice, the state of one qubit can be transported to another qubit on the lattice using QCA. Such a phenomenon represents the possibility of a communication channel between different positions on the lattice. Simulations of the two-dimensional lattice using the stabilizer formalism with proper initial and boundary conditions are demonstrated. Furthermore, various errors on the gates of the system are simulated, and error probabilities on the final results are reported. Finally, encoding schemes using qubit arrays are also investigated.

J. Seo, H. Ait-Kaci, R. Nasr

Abstract
This report discusses the implementation of a knowledge base for a library information system. It is done using a typed logic programming language—LOGIN—where type inheritance is built in. The knowledge base is structured in a hierarchical taxonomy of library object classes where each class is represented in a FRAME style knowledge structure and inherits the properties of its parents, and where infrastructural inference rules have been established through typed Horn clauses. Also in this document, some programming techniques aimed at using the power of inheritance as taxonomic inference are discussed.

Böckenhauer, Jens

Abstract
Based on the treatment of the chiral Ising model by Mack and Schomerus, we present examples of localized endomorphisms. It is shown that they lead to the same superselection sectors as the global ones in the sense that unitary equivalence holds. Araki's formalism of the selfdual CAR algebra is used for the proof. We prove local normality and extend representations and localized endomorphisms to a global algebra of observables which is generated by local von Neumann algebras on the punctured circle. In this framework, we manifestly prove fusion rules and derive statistics operators.

Amin, Saurabh; Hante, Falk M.; and Bayen, Alexandre M.

Abstract
We consider stability of an infinite dimensional switching system, posed as a system of linear hyperbolic partial differential equations (PDEs) with reflecting boundaries, where the system parameters and the boundary conditions switch in time. Asymptotic stability of the solution for arbitrary switching is proved under commutativity of the advective velocity matrices and a joint spectral radius condition involving the boundary data.

Pozhela, Yu K; Starikov, E V; and Shiktorov, P N.

Abstract
The frequency dependence of the longitudinal differential mobility of hot electrons is calculated using velocity averaging over the before- and after- scattering ensembles by the single-particle Monte Carlo simulation of the steady state. A dynamic negative differential mobility (NOM), due to the transit-time resonance of hot electrons in the momentum space under the predominant role of spontaneous emission of optical phonons at low lattice temperature, is observed in n-lnP. The frequency- and field-behaviour of the NOM and the noise characteristics, as well as the possibilities to use the effect for amplification and generation of the millimetre-wave radiation, are investigated. The techniques for the experimental investigation of the transit-time resonance are discussed. The noise temperature measurements are shown to be the most suitable tool for this. The transit-time resonance characteristics in n-lnP are compared with the experimentally realized and theoretically calculated parameters of the cyclotron resonance NEMAG in p-Ge. The conditions for the generation and amdification are found to be better in the former case than in the latter one.

Sourour, Essam and Nakagawa, Masao

Abstract
Data exchange among vehicles can improve road safety and capacity. Most of the proposed intervehicle data communication systems require intervehicle synchronization. Synchronization must be done in a decentralized manner. In this paper, we propose a new mutual decentralized synchronization system. Using a devoted carrier frequency, each vehicle transmits a continuous periodic train of pulses. The aim of the synchronization system is to make these periodic pulses synchronous to indicate the start of data slots in slotted ALOHA types of media access protocol. Each vehicle measures the power of pulses of other vehicles as well as the time difference between other pulses and its own pulse. Using this information, each vehicle shifts its own pulse transmission time toward a weighted average of other pulse transmission times. Eventually, all periodic pulse trains are synchronized. The system performance is evaluated in nonfading and fading channels.