Decoherence of quantum states and its suppression in ensemble large-scale solid state NMR quantum computers

It is discussed the decoherence problems in ensemble large-scale solid state NMR quantum computer based on the array of P donor atoms having nuclear spin I = 1/2. It is considered here, as main mechanisms of decoherence for low temperature (< 0.1 K), the adiabatic processes of random modulation of qubit resonance frequency determined by secular part of nuclear spin interaction with electron spin of the basic atoms, with impurity paramagnetic atoms and also with nuclear spins of impurity diamagnetic atoms. It was made estimations of allowed concentrations of magnetic impurities and of spin temperature whereby the required decoherence suppression is obtained. It is discussed the random phase error suppression in the ensemble quantum register basic states.Comment: LaTeX 7 pages. Submitted to Proceedings of SPIE. International Symposium Quantum Informatics (QI-2002), October 2002, Zvenigorod, Russi

The controlled indirect coupling between spatially-separated qubits in antiferromagnet-based NMR quantum registers

It is considered the indirect inter-qubit coupling in 1D chain of atoms with nuclear spins 1/2, which plays role of qubits in the quantum register. This chain of the atoms is placed by regular way in easy-axis 3D antiferromagnetic thin plate substrate, which is cleaned from the other nuclear spin containing isotopes. It is shown that the range of indirect inter-spin coupling may run to a great number of lattice constants both near critical point of quantum phase transition in antiferromagnet of spin-flop type (control parameter is external magnetic field) and/or near homogeneous antiferromagnetic resonance (control parameter is microwave frequency).Comment: Latex 5 pages, 1 figure. Presented at International Symposium "Quantum Informatics 2004" Moscow, October 5-8, 2004. Will be published in Proc. SPI

Fuzzy neural networks' application for substation integral state assessment

This paper addresses the problems connected with fuzzy neural networks' application in equipment technical state assessment problems at electrical substations. This paper discusses the main principles of fuzzy neural network formation and its construction algorithm. Also, the case study for the determination of fuzzy neural network synaptic weights for the unit "disconnector" on the basis of technical diagnostic statistical data and tests is presented. © 2014 WIT Press.International Journal of Safety and Security Engineering;International Journal of Sustainable Development and Planning;WIT Transactions on Ecology and the Environmen

Проблема подклассовых признаков в судебно-баллистической идентификации

The Russian school of forensic firearms investigation traditionally recognizes common and individual features of traces on bullets and cartridge cases. The first are characteristics inherent in all weapons of the same model and describing their details in general: shape, size, location, relative position. The second type are individual characteristics, which are unique and present only in one firearm. The individual features are used for forensic identification, while the common can be used only for the identification of a firearm’s type and model.  The Western (West Europe and the USA) methodology of forensic ballistic identification recognizes the third type of traits – subclass characteristics. These marks are the result of manufacturing processes and can be present in a group of sequentially produced parts. Conventionally they can be placed between class and individual characteristics. One of the problems in contemporary firearms identification is the wrong recognition of subclass marks as individual marks and, as a result, giving false-positive conclusions of identification.  The article discusses the problem of subclass features, gives examples, presents a review of the literature. The influence of various technological processes on the possibility of showing up of these marks is described.  В российской школе судебно-баллистической идентификации в следах оружия на пулях и гильзах принято выделять общие и частные признаки. Первая группа – это признаки, присущие всем экземплярам оружия одной модели и характеризующие их детали в целом: форма, размеры, расположение, взаиморасположение. Вторая группа – это частные (индивидуальные) признаки, ко­торые уникальны и проявляются только в одном экземпляре оружия. Частные признаки использу­ются для криминалистической идентификации, в то время как общие признаки могут применяться только для определения типа и модели огнестрельного оружия.  В западной методологии (Европа и США) судебно-баллистической идентификации выделяется еще и третий тип признаков – подклассовые. Эти признаки являются результатом производственных процессов и могут быть представлены в их следах в группе последовательно изготовленных де­талей. Условно их можно расположить между общими и частными признаками. Одной из проблем современной идентификации огнестрельного оружия является ложное восприятие подклассовых признаков как частных и, как результат, формулирование ошибочного положительного вывода о тождестве.  В статье рассмотрена проблема подклассовых признаков, приведены примеры и обзор литературы. Описано влияние различных технологических процессов на возможность проявления этого типа признаков.