Novel Reversible TSG Gate and Its Application for Designing Components of Primitive Reversible/Quantum ALU

In recent years, reversible logic has emerged as a promising computing paradigm having application in low power CMOS, quantum computing, nanotechnology, and optical computing. The classical set of gates such as AND, OR, and EXOR are not reversible. This paper utilizes a new 4 * 4 reversible gate called TSG gate to build the components of a primitive reversible/quantum ALU. The most significant aspect of the TSG gate is that it can work singly as a reversible full adder, that is reversible full adder can now be implemented with a single gate only. A Novel reversible 4:2 compressor is also designed from the TSG gate which is later used to design a novel 8x8 reversible Wallace tree multiplier. It is proved that the adder, 4:2 compressor and multiplier architectures designed using the TSG gate are better than their counterparts available in literature, in terms of number of reversible gates and garbage outputs. This is perhaps, the first attempt to design a reversible 4:2 compressor and a reversible Wallace tree multiplier as far as existing literature and our knowledge is concerned. Thus, this paper provides an initial threshold to build more complex systems which can execute complicated operations using reversible logic.Comment: 5 Pages; Published in Proceedings of the Fifth IEEE International Conference on Information, Communications and Signal Processing (ICICS 2005), Bangkok, Thailand, 6-9 December 2005,pp.1425-142

Membrane Computing as a Modeling Framework. Cellular Systems Case Studies

Membrane computing is a branch of natural computing aiming to abstract computing models from the structure and functioning of the living cell, and from the way cells cooperate in tissues, organs, or other populations of cells. This research area developed very fast, both at the theoretical level and in what concerns the applications. After a very short description of the domain, we mention here the main areas where membrane computing was used as a framework for devising models (biology and bio-medicine, linguistics, economics, computer science, etc.), then we discuss in a certain detail the possibility of using membrane computing as a high level computational modeling framework for addressing structural and dynamical aspects of cellular systems. We close with a comprehensive bibliography of membrane computing applications

Simulating the Fredkin Gate with Energy-Based P Systems

Reversibility plays a fundamental role when the possibility to perform computations with minimal energy dissipation is considered. Many papers on reversible computation have appeared in literature, the most famous of which is certainly the work of Bennett on (universal) reversible Turing machines. Here we consider the work of Fredkin and Toffoli on conservative logic, which is a mathematical model that allows to describe computations which reflect some properties of microdynamical laws of physics, such as reversibility and conservation of the internal energy of the physical system used to perform the computations. The model is based upon the Fredkin gate, a reversible and "conservative" (according to a definition given by Fredkin and Toffoli) three-input/three-output boolean gate. In this paper we introduce energy{based P systems as a parallel and distributed model of computation in which the amount of energy manipulated and/or consumed during computations is taken into account. Moreover, we show how energy-based P systems can be used to simulate the Fredkin gate. The proposed P systems that perform the simulations turn out to be themselves reversible and conservative