The Graphics Processing Units (GPUs), or Graphics Cards, were originally designed to perform dedicated tasks to the computer graphics operations. Recently, however, NVIDIA has developed an extension of the C language ...
详细信息
ISBN:
(纸本)9781617820663
The Graphics Processing Units (GPUs), or Graphics Cards, were originally designed to perform dedicated tasks to the computer graphics operations. Recently, however, NVIDIA has developed an extension of the C language for programming GPUs, called CUDA (Compute Unified Device Architecture). Density Functional Theory (DFT) is one of the most used iterative methods to find an approximate solution to the Schrödinger equation. However, the calculations in DFT are computationally intensive because of the exchange and correlation electronic integrals, integrals to calculate the Hartree and kinetic energies, which require more computational effort as the number of electrons in the simulation increases. The development of the GPU and tools focused on the concept of General-Purpose computation on Graphics Processing Units (GPGPU) is an alternative to accelerate the energy calculation in the DFT method. This research aimed to study the DFT calculations and identify parts of the algorithm that, if changed, could represent performance benefits to be executed on GPU. The SIESTA (Spanish Initiative for Electronic Simulations with Thousands of Atoms) is a DFT method that uses pseudopotencial for ionic core representation, numerical atomic orbitals and localized basis set. In this research, some functions of this method ware parallelized and used to calculate the physical properties of nanotubes in order to prove the efficiency of GPUs. It was found that the implementation of SIESTA GPU parallel version is able to achieve gains in performance, in individual functions, of one or even two orders of magnitude, making it promising employment of GPUs to speed up the processing of the Density Functional Theory.
The volume of energy loss that Brazilian electric utilities have to deal with has been ever increasing. The electricity concessionaries are suffering significant and increasing loss in the last years, due to theft, me...
详细信息
The volume of energy loss that Brazilian electric utilities have to deal with has been ever increasing. The electricity concessionaries are suffering significant and increasing loss in the last years, due to theft, measurement errors and many other kinds of irregularities. Therefore, there is a great concern from those companies to identify the profile of irregular customers, in order to reduce the volume of such losses. This paper presents the proposal of an intelligent system, composed of two neural networks ensembles, which intends to increase the level of accuracy in the identification of irregularities among low tension consumers. The data used to test the proposed system are from Light S.A. Company, the Rio de Janeiro concessionary. The results obtained presented a significant increase in the identification of irregular customers when compared to the current methodology employed by the company.
The huge performance superiority of quantum computers for some specific problems lies in their direct use of quantum mechanical phenomena (e.g. superposition of states) to perform computations. This has motivated the ...
详细信息
The huge performance superiority of quantum computers for some specific problems lies in their direct use of quantum mechanical phenomena (e.g. superposition of states) to perform computations. This has motivated the creation of quantum-inspired evolutionary algorithms (QIEAs), which successfully use some quantum physics principles to improve the performance of evolutionary algorithms (EAs) for classical computers. This paper proposes a novel QIEA (Quantum-Inspired Linear Genetic Programming - QILGP) for automatic synthesis of machine code (MC) programs and aims to present a preliminary evaluation of applying the quantum-inspiration paradigm to evolve programs by using two symbolic regression problems. QILGP performance is compared to AIMGP model, since it is the most successful genetic programming technique to evolve MC. In the first problem, the hit ratio of QILGP (100%) is greater than the one of AIMGP (77%). In the second problem, QILGP seems to carry on a less greedy search than AIMGP. Since QILGP presents some satisfactory results, this paper shows that the quantum-inspiration paradigm can be a competitive approach to evolve programs more efficiently, which encourages further developments of that first and simplest QILGP model with multiple individuals.
In the last years, with a more realistic vision of a possible limit for miniaturization of components with conventional CMOS technology, a new technology has surfaced - the Molecular Electronics which, from the bottom...
详细信息
ISBN:
(纸本)0769523994
In the last years, with a more realistic vision of a possible limit for miniaturization of components with conventional CMOS technology, a new technology has surfaced - the Molecular Electronics which, from the bottom-up approach, aims at the construction of electrical devices to implement computation using individual or small collection of molecules, offering an alternative way to build nanoscale circuits. These circuits have the potential to reduce device size and fabrication costs by several orders of magnitude relative to conventional CMOS. Recently, some mechanisms have been considered as a basis to molecular electronic systems design. Two terminal molecular devices that work as diodes have been synthesized, with similar behavior to rectifying and tunnel diodes. In this article, a study on the synthesis of molecular circuits is presented, integrating simulated molecular devices as the Molecular Tour-Reed Diode based on the Evolvable Hardware (EHW) paradigm.
With a more realistic vision of a possible limit for miniaturization of components with conventional CMOS technology, a new technology has surfaced -molecular electronics which, from the bottom-up approach, aims at th...
详细信息
With a more realistic vision of a possible limit for miniaturization of components with conventional CMOS technology, a new technology has surfaced -molecular electronics which, from the bottom-up approach, aims at the construction of electrical devices to implement computation using individual or small collections of molecules, offering an alternative way to build nanoscale circuits. These circuits have the potential to reduce device size and fabrication costs by several orders of magnitude relative to conventional CMOS. Recently, some mechanisms have been considered as a basis to molecular electronic systems design. Two terminal molecular devices that work as diodes have been synthesized, with similar behavior to rectifying and tunnel diodes. In this article, a study on the synthesis of molecular circuits is presented, integrating simulated molecular devices as the molecular Tour-Reed diode based on the evolvable hardware (EHW) paradigm.
This work presents the development of a methodology based on Monte Carlo Simulation, Fuzzy Numbers and in the Real Options Theory to determine the real options value under technical and market uncertainties. The objec...
详细信息
This work presents the development of a methodology based on Monte Carlo simulation, fuzzy numbers and in the real options theory to determine the real options value under technical and market uncertainties. The objec...
详细信息
This work presents the development of a methodology based on Monte Carlo simulation, fuzzy numbers and in the real options theory to determine the real options value under technical and market uncertainties. The objective of the proposed methodology is to substantially reduce the computational time involved, facilitating the decision taking process. The methodology involves: fuzzy numbers, to represent certain types of uncertainties that does not have a known stochastic process that can correctly model them; stochastic processes to represent other uncertainties; and Monte Carlo simulation to generate a good approximation of the real option value. This methodology was evaluated in problems of expansion option in the area of oil exploration and production, attaining the same results provided by conventional techniques but with a significant reduction in the necessary computational time.
This work discusses an Evolvable Hardware (EHW) platform for the intrinsic evolution of analog electronic circuits. The EHW analog platform, named PAMA-NG (Programmable Analog Multiplexer Array-Next Generation), is a ...
详细信息
This paper describes a reconfigurable platform for exploring the intrinsic evolution of analog hardware. The reconfigurable platform consists of integrated circuits whose internal connections can be programmed by the ...
详细信息
ISBN:
(纸本)0780365992
This paper describes a reconfigurable platform for exploring the intrinsic evolution of analog hardware. The reconfigurable platform consists of integrated circuits whose internal connections can be programmed by the user. Automatic reconfiguration may potentially be driven by Evolutionary Computation techniques such as Genetic Algorithms to synthesize complex circuits. Field Programmable Gate Arrays (FPGAs) and Field Programmable Analog Arrays (FPAAs) constitute the state of the art in the technology of reconfigurable chips, referring to digital and analog devices respectively. These devices will become the building blocks of a forthcoming class of hardware, that will encompass important features of self-adaptation and self-repairing through automatic reconfiguration. These are essential features for systems that need to perform for a long time in harsh environments such as those employed in space exploration missions. In this paper, the reconfigurable platform architectural details, concept and some preliminary tests are presented.
This paper describes PAMA (Programmable Analog Multiplexer Array), a reconfigurable platform for exploring the intrinsic evolution of analog hardware. The reconfigurable platform consists of integrated circuits whose ...
详细信息
ISBN:
(纸本)0769511805
This paper describes PAMA (Programmable Analog Multiplexer Array), a reconfigurable platform for exploring the intrinsic evolution of analog hardware. The reconfigurable platform consists of integrated circuits whose internal connections can be programmed by the user. The platform characteristics are discussed, such as it's flexibility, once the discrete components can be of any type (fine or coarse grained). This latest PAMA version described in this paper presents some advantages concerning the prototype platform which was first used to intrinsically evolve circuits. The Analog Reconfigurable Circuit allows more component terminals, allowing the evolution of a great number of circuits and the circuit evaluation time has decreased considerably.
暂无评论