14 research outputs found
A Reconfigurable Computing Solution to the Parameterized Vertex Cover Problem
Active research has been done in the past two decades in the field of computational intractability. This thesis explores parallel implementations on a RC (reconfigurable computing) platform for FPT (fixed-parameter tractable) algorithms.
Reconfigurable hardware implementations of algorithms for solving NP-Complete problems have been of great interest for research in the past few years. However, most of the research that has been done target exact algorithms for solving problems of this nature. Although such implementations have generated good results, it should be kept in mind that the input sizes were small. Moreover, most of these implementations are instance-specific in nature making it mandatory to generate a different circuit for every new problem instance.
In this work, we present an efficient and scalable algorithm that breaks out of the conventional instance-specific approach towards a more general parameterized approach to solve such problems. We present approaches based on the theory of fixed-parameter tractability. The prototype problem used as a case study here is the classic vertex cover problem. The hardware implementation has demonstrated speedups of the order of 100x over the software version of the vertex cover problem
Beta Macrophyta Diversity Analysis in the Temporary Pond Habitats of Vettangudi Birds Sanctuary
Three temporary ponds of Vettangudi birds sanctuary situate in very close proximity, located in Sivaganga District, Tamil Nadu state of India. However similar eco-climatic conditions prevailing at these pond habitat, those ponds experience the varying nature of biotic interactions. Since the habitat conditions and their land-use pattern have the major role on the vegetation diversity. Temporary ponds of Vettangudi Birds Sanctuary has the characteristic alternate drying and inundation at varying levels and this environmental condition in addition to the biotic influence over the habitat ecology and its vegetation diversity. Understanding this specific relationship is pivotal in the development of management guidelines in the pond habitat and wildlife management. The aim was to investigate the floristic composition and diversity analysis of the floor vegetation of benthic and shore-line of temporary ponds of Vetttangudi Birds Sanctuary in four different seasons in a year. A wide range of Sorenson’s similarity index was found existed among the experimental ponds. Margleaf’s richness index values were also observed with variations and the occurrence of floristic composition and their diversity variations were attempted to relate with the prevalent habitat conditions, experienced with varying kind of biotic influence
Quantum information processing by NMR using a 5-qubit system formed by dipolar coupled spins in an oriented molecule
Quantum Information processing by NMR with small number of qubits is well
established. Scaling to higher number of qubits is hindered by two major
requirements (i) mutual coupling among qubits and (ii) qubit addressability. It
has been demonstrated that mutual coupling can be increased by using residual
dipolar couplings among spins by orienting the spin system in a liquid
crystalline matrix. In such a case, the heteronuclear spins are weakly coupled
but the homonuclear spins become strongly coupled. In such circumstances, the
strongly coupled spins can no longer be treated as qubits. However, it has been
demonstrated elsewhere, that the energy levels of a strongly coupled N
spin-1/2 system can be treated as an N-qubit system. For this purpose the
various transitions have to be identified to well defined energy levels. This
paper consists of two parts. In the first part, the energy level diagram of a
heteronuclear 5-spin system is obtained by using a newly developed
heteronuclear z-cosy (HET-Z-COSY) experiment. In the second part,
implementation of logic gates, preparation of pseudopure states, creation of
entanglement and entanglement transfer is demonstrated, validating the use of
such systems for quantum information processing.Comment: 23 pages, 8 figure
Hadamard NMR spectroscopy for two-dimensional quantum information processing and parallel search algorithms
Hadamard spectroscopy has earlier been used to speed-up multi-dimensional NMR
experiments. In this work we speed-up the two-dimensional quantum computing
scheme, by using Hadamard spectroscopy in the indirect dimension, resulting in
a scheme which is faster and requires the Fourier transformation only in the
direct dimension. Two and three qubit quantum gates are implemented with an
extra observer qubit. We also use one-dimensional Hadamard spectroscopy for
binary information storage by spatial encoding and implementation of a parallel
search algorithm.Comment: 28 pages, 10 figures. Journal of Magnetic Resonance (In Press
Implementation of a Deutsch-like quantum algorithm utilizing entanglement at the two-qubit level, on an NMR quantum information processor
We describe the experimental implementation of a recently proposed quantum
algorithm involving quantum entanglement at the level of two qubits using NMR.
The algorithm solves a generalisation of the Deutsch problem and distinguishes
between even and odd functions using fewer function calls than is possible
classically. The manipulation of entangled states of the two qubits is
essential here, unlike the Deutsch-Jozsa algorithm and the Grover's search
algorithm for two bits.Comment: 4 pages, two eps figure
Use of Quadrupolar Nuclei for Quantum Information processing by Nuclear Magnetic Resonance: Implementation of a Quantum Algorithm
Physical implementation of Quantum Information Processing (QIP) by
liquid-state Nuclear Magnetic Resonance (NMR), using weakly coupled spin-1/2
nuclei of a molecule, is well established. Nuclei with spin1/2 oriented in
liquid crystalline matrices is another possibility. Such systems have multiple
qubits per nuclei and large quadrupolar couplings resulting in well separated
lines in the spectrum. So far, creation of pseudopure states and logic gates
have been demonstrated in such systems using transition selective
radio-frequency pulses. In this paper we report two novel developments. First,
we implement a quantum algorithm which needs coherent superposition of states.
Second, we use evolution under quadrupolar coupling to implement multi qubit
gates. We implement Deutsch-Jozsa algorithm on a spin-3/2 (2 qubit) system. The
controlled-not operation needed to implement this algorithm has been
implemented here by evolution under the quadrupolar Hamiltonian. This method
has been implemented for the first time in quadrupolar systems. Since the
quadrupolar coupling is several orders of magnitude greater than the coupling
in weakly coupled spin-1/2 nuclei, the gate time decreases, increasing the
clock speed of the quantum computer.Comment: 16 pages, 3 figure