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The results of the spark channel expansion simulation in various gases such as hydrogen, oxygen and nitrogen have been presented. Difference in thermodynamic properties of the various gases has been taken into account. Influence of a type of gas on the discharge current, the spark resistance, the energy deposited in the spark and the spark gas-dynamic expansion has been found out. Influence of initial species concentration in mixture of nitrogen, hydrogen and oxygen on detonation initiation by spark discharge has been discussed.

Despite the widespread occurrence of ischemic diseases of the lower extremities, including atherosclerosis and diseases with an autoimmune component of their pathogenesis, the pathohistological signs of damage and concomitant chronic ischemia, compensatory tissue responses as intracellular and cellular regeneration remain out of the field of vision in researchers.To assess the signs of damage (the extent of necrosis and apoptosis, capillary density (CD)) and regeneration (the cross-sectional muscle fiber area (CSMFA), the proportion of centrinucleated muscle fibers (CNMFs), and that of connective tissue), by using the gastrocnemius medial head biopsy specimens obtained from patients with heterogeneous forms of chronic lower limb obliterating diseases (CLLODs).The investigation included the biopsy specimens obtained from 44 men under 65 years of age (their mean age was 54±9.8 years) with Stage IIB-IV chronic limb ischemia (according to the A.V. Pokrovsky-Fontaine classification) with its history of at least six months. The nosological entities were atherosclerotic lesion in 33 patients (distal atherosclerosisIt was found that there was a statistically significant difference between the nosological entities, as compared to the control in terms of CD and CSMFA (a decrease), the proportion of CNMFs and that of connective tissue (an increase). No substantial differences were found in the studied parameters between the nosological entities.The findings may suggest the universal mechanism for damage to striated muscle tissue because of circulatory hypoxia, regardless of its etiology and the common character of tissue compensatory-adaptive responses (regeneration).Несмотря на широкое распространение ишемических заболеваний нижних конечностей, включающих атеросклероз и болезни с аутоиммунным компонентом патогенеза, патогистологические признаки повреждения и сопутствующие хронической ишемии компенсаторные тканевые реакции в виде внутриклеточной и клеточной регенерации остаются вне поля зрения исследователей.На материале биопсий медиальной головки икроножных мышц, полученных от пациентов с гетерогенными формами хронических облитерирующих заболеваний нижних конечностей, оценить признаки повреждения (выраженность некроза и апоптоза, капиллярная плотность — КП) и регенерации (площадь поперечного сечения мышечных волокон — ППСМВ, доля центральноядерных мышечных волокон — ЦЯМВ, доля соединительной ткани).В исследование включены биоптаты, полученные от 44 мужчин с хронической ишемией IIБ—IV степени (по Покровскому — Фонтейну) в возрасте до 65 лет (средний возраст составил 54±9,8 года), страдающих заболеванием не менее 0,5 года. Нозологическая структура: атеросклеротическое поражение у 33 пациентов (дистальный атеросклероз — 13, «многоэтажное поражение» — 8, синдром Лериша — 12); аутоиммунное поражение сосудов у 11 пациентов (болезнь Бюргера — 7, неспецифический аортоартериит — 4). В качестве контроля исследованы аналогичные фрагменты мышц, полученные в ходе аутопсии у умерших без выраженных признаков заболеваний сердечно-сосудистой системы.Установлено, что статистически значимая разница между нозологиями по сравнению с контролем имеется по показателям КП и ППСМВ (уменьшение), доля ЦЯМВ и доля соединительной ткани (увеличение). Значимых различий в исследованных показателях между нозологическими формами не обнаружено.Полученные сведения позволяют предположить универсальность механизма повреждения поперечнополосатой мышечной ткани в связи с циркуляторной гипоксией вне зависимости от ее этиологии и общность тканевых компенсаторно-приспособительных реакций (регенерации).

The problem of designing reliable on-board radio electronic equipment is a priority for the development of aerospace instrumentation in Russia. The search for new concepts of the design of on-board equipment architectures is aimed at satisfying the requirements of modularity, regularity, uniformity, multi functionality, fault tolerance and reconfigurability on the basis of integrated structures of standard hardware-software modules. As a rule, through the organization of parallel design together with the equipment a tool for functional monitoring of its condition is created. The implementation of a diagnostic monitoring of the on-board equipment condition without a reference standard by means of an invariant approach is proposed in this paper. The essence of this approach is to identify characteristics, which remain unchanged with the equipment normal functioning and change when defects appear in its operation. The monitoring of the onboard equipment condition is carried out by reconfiguring its architecture for the observation time. The on-board equipment configuration change consists in its division into duplicated pairs of homogeneous subsystems, blocks or standard modules. The state monitoring is made by a comparative analysis of the subsystems characteristics in the formed pairs. The diagnostic procedure is performed only for those pairs that have mismatched states. The addresses of the found systems with deviations are identified by the subsequent reconfiguration of the on-board equipment.

UniTESK (UNIfied TEsting and Specification toolKit) is a testing technology based on formal models (or specifications) of requirements to behavior of software or hardware components. It was created with experience gained during development of the framework for automated testing of a real-time operating system kernel during 1994-2000. Software contracts were the main kind of models in the first version of the technology. Automata models were also implemented to support generation of complicated test sequences. UniTESK was first used in 2000 in the development of the test suite for IPv6 implementation. It was the first experience of using contract specifications in testing of implementations of telecommunication protocols. This project demonstrated that contract specifications in combination with the technique of testing software systems with asynchronous interface developed within UniTESK are very effective. Applications of UniTESK to testing software components in Java include the project on testing of implementation of standard library for Java runtime support and the project on testing of infrastructure of information system for one of large mobile operators in Russia. The most significant application of UniTESK happened in 2005-2007 in the Open Linux Verification project. Formal specifications and tests for interfaces of the Linux Standard Base were created during the project. These results then were used in development of the test suite for Russian avionics real-time operating system. Positive lessons learned during development and using UniTESK include effective application of model based testing methods in large industrial projects, high level of test coverage achieved by the generated tests, applicability of model based testing to critical systems and applications. Negative lessons include the lack of well-defined and detailed models and specifications, extra development expenses caused by creation of test specific models, problems with introduction of model based testing technologies using bilingual test generation systems and specific notations.

The decay φ → η ′ γ has been observed by the CMD-2 detector at the e + e − collider VEPP-2M at Novosibirsk. Of 5.5 million produced φ 's, six events of the φ → η ′ γ decay were selected with the expected background less than one event. The corresponding branching ratio is B( φ → η ′ γ )=1.2 +0.7 −0.5 ·10 −4 . It is the first observation of this radiative decay.

A search for φ radiative decays has been performed using a data sample of about 2.0 million φ decays collected by the CMD-2 detector at VEPP-2M collider in Novosibirsk. From the selected e + e − → π + π − γ events the following results were obtained: B( φ → f 0 (980) γ ) −4 for destructive and B( φ → f 0 (980) γ ) −4 for constructive interference with the Bremsstrahlung process respectively, B( φ → γ → π + π − γ ) −5 for E γ >20 MeV, B( φ → ργ ) −4 . From the selected e + e − → μ + μ − γ events B( φ → μ + μ − γ )=(2.3±1.0)×10 −5 has been obtained for E γ >20 MeV. The upper limit on the P,CP-violating decay η → π + π − has also been placed: B( η → π + π − ) −4 . All upper limits are at 90% C.L.

Results of the measurement of the φ meson parameters with the general purpose detector CMD-2 at the upgraded e + e − collider VEPP-2M at Novosibirsk are presented. This is the first measurement of the four major φ decay modes in a single e + e − experiment. The results based on about 55,600 identified hadronic events are consistent with previous measurements, and have precision comparable to the current world average.

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On faculty of industrial electronics NSTU some years works on creation of all a component of the electronic training environment at the discipline Lt Fundamentals of power electronics Gt are conducted. The electronic textbook with the electronic test, computer versions of laboratory works, electronic databases has been created. The specified stage of education can be executed by the student without the help of the teacher. The following problem in automation of training consists now in clearing the teacher of routine work on check at each student of variants of his practical calculations of electric parameters of converter elements. It can be made by creation of a simulator of mathematical formulas of such calculations. Complex nonsinusoidal forms of voltages and currents in converters cause difficulties in students at construction of settlement formulas of integrated values for such forms. At independent studying bases of power electronics the software realizing functions of a simulator is developed.

The muon anomalous magnetic moment has been measured in a new experiment at Brookhaven. Polarized muons were stored in a superferric ring, and the angular frequency difference, {omega}{sub a} , between the spin precession and orbital frequencies was determined by measuring the time distribution of high-energy decay positrons. The ratio R of {omega}{sub a} to the Larmor precession frequency of free protons, {omega}{sub p} , in the storage-ring magnetic field was measured. We find R=3.707thinsp220(48){times}10{sup {minus}3} . With {mu}{sub {mu}}/{mu}{sub p}=3.183thinsp 345thinsp47(47) this gives a{sub {mu}{sup +}}=1thinsp165thinsp 925(15){times}10{sup {minus}9} ({plus_minus}13 ppm ), in good agreement with the previous CERN measurements for {mu}{sup +} and {mu}{sup {minus}} and of approximately the same precision. {copyright} {ital 1999} {ital The American Physical Society}

The general purpose detector CMD-2 at the VEPP-2M electron-positron collider at Novosibirsk has collected about 11 pb−1 of integrated luminosity in the center-of-mass energy range from 0.36 up to 1.38 GeV. Data in the ρ-meson energy range from 0.61 to 0.96 GeV have been analysed and preliminary results on the e+e−→π+π− cross-section in this energy range are presented.

The integrated luminosity about 4000 inverse nanobarn of around phi meson mass ( 5 millions of phi mesons) has been collected with the CMD-2 detector at the VEPP-2M collider. A latest analysis of the KS KL coupled decays based on 30 % of available data is presented in this paper. The KS KL pairs from phi meson decays were reconstructed in the drift chamber when both kaons decayed into two charged particles. From a sample of 1423 coupled decays a selection of candidates to the CP violating KL into pi+ pi- decay was performed. CP violating decays were not identified because of the domination of events with a KL regenerating at the Be beam pipe into KS and a background from KL semileptonic decays. The regeneration cross section of 110 MeV/c KL mesons was found to be 53 +- 17 mb in agreement with theoretical expectations. The angular distribution of KS mesons after regeneration and the total cross section of KL for Be have been measured., Comment: 14 pages, 8 figures

A new general‐purpose detector CMD‐2 (calorimetric magnetic detector) has started experiments at the upgraded e+e− collider VEPP‐2M (collider for electron‐positron beams) at Novosibirsk. During early runs an integrated luminosity of about 400 inverse nanobarns has been collected in the center of mass energy range 400–1030 MeV.

CMD-2 [1] is currently studying e + e − annihilation in the energy range from 0.36 GeV to 1.4 GeV. The planned upgrade [2] of the VEPP-2M collider facility will increase the luminosity of the machine from 5 × 10 30 cm −2 s −1 up to 2 × 10 31 −10 32 . The expected increase in data rates is beyond the capacity of the operational data acquisition system (DAQ) and necessitates the design of a new system.

The experience gained during four years of operation of the CMD-2 drift chamber is reported. Offline calibration of the DC parameters using a sample of Bhabha scattering events is described. Fine corrections to the Lorentz angle allow one to improve the momentum resolution. The systematic error in the determination of the polar angle was substantially decreased when information from the Z-chamber cathode was used for calibration.

Statistical and relaxation properties have been studied on dynamic models of a two-dimensional system consisting of oriented chains with kinetic units formed by rigid segments smaller in size than the statistical chain segment. Depending on the ratio between the energy of thermal motion and the geometric mean of energies that characterize the chain rigidity with respect to bending and the orientational interaction between chains, the dependence of the mean-square dimension of a long but finite section of chain embedded in the ordered matrix on the number of segments can assume several forms. The relaxation times in various modes of motion in the entire system of chains are proportional to the mean-square fluctuation corresponding to the given normal mode.

The conformational properties of dynamic models of three-dimensional systems of different lengths (domains) consisting of orientationally ordered N 2 N 3 planar chains, each of which consists of N 1 rigid segments shorter than the statistical chain segment, are considered. For elongated thin domain ( N 1 → ∞) of finite thickness ( N 2 and N 3 being finite) the correlations of orientation between segments of a particular chain, separated by a spacing p > p 1 , are similar to the correlations in thick persistent chains, but for p 1 > p > p 2 , the correlations are similar to those in extended planar layers. An analysis has been made of the various regions of behaviour of the statistical properties of a domain as a function of the domain thickness, the chain rigidity and the magnitude of the interchain orientational interactions.

Analysis of the statistical properties of a three-dimensioonal system of ordered chains at quite high values of the order parameter has been carried out using a method employed to calculate the fluctuations in the orientation of particles in low-molecular weight nematic single crystals. The degree of order, the mean-square projection of the chain-length vector h in the direction of the axis of order, z , (√〈 h ∥ 2 〉) and on the x , y plane normal to the axis (√〈 h ⊥ 2 〉) have been calculated as functions of the ratio of the energy of thermal motion to the energy constants characterizing the chain rigidity in bending and the interchain orientational interaction. Unfolding of the chain in the direction of the axis of order appears as an increase in 〈 h ∥ 2 〉 and a decrease in 〈 h ⊥ 2 〉 as the degree of order rises. The effective coefficient of translational diffusion of the chain as a whole in the direction of the axis of order increases, and its ability to diffuse transverse to this direction decreases, as the degree of order of the chains increases.

The conformational and dynamic properties of two- (d2) and three- (d3) dimensional “network” systems consisting of polymeric chains orientationally ordered at the level of Gaussian sub-chains have been considered. If the sub-chains have comparatively weak orientation-strain interaction and the flexural regidity of the chain is low, a long chain included in the ordered matrix remains Gaussian. As the constant for the interchain interaction increases, the mean-square dimensions of the sub-chains and chains increase. In both models there is a “critical” point at which the system of Gaussian sub-chains loses its stability. At this point, the mean-square dimensions of the Gaussian sub-chains either become infinitely large (in the d2 model) or remain finite (in the d3 model). On passing through the “critical point”, it is necessary to take account of the finite extensibility of the sub-chains and to go on to a theoretical description based on chains made up of rigid segments.

The characteristic relaxational functions determining the average cosine and average square of the cosine of the angle of rotation of a given chain segment are calculated for a three-dimensional model of planar chains with long-range orientational order. The times of the local motions are inversely related to the increase in order. Two relaxational spectra are determined for the large-scale motions, i.e. τ⊥(ψ) and τ‖(ψ) for lateral and longitudinal (towards the order axis) relaxational processes. For high degree of order τ⊥(ψ) and τ‖(ψ) are inversely related to long-range orientational order, while β(ψ) = τ‖(ψ)/τ⊥(ψ)

A reverse torsion pendulum is described, connected with the “Iskra-1256” computer. The apparatus is suited for measuring the characteristics of viscoelastic behaviour of materials at 77–500 K. From the results of measurement in the glass-transition range, the parameters of the model of a standard linear viscoelastic solid and the activation energy of the glass-transition process can be determined. Temperature control, collection and treatment of accumulating information are performed by the computer in a programmed regime.