ABSTRACT MODELS FOR SYSTEM VIRTUALIZATION

The paper is dedicated to issues of system objects securing (system files and user system or application configuration files) against unauthorized access including denial of service attacks. We have suggested the method and developed abstract system virtualization models, which are used toresearch attack scenarios for different virtualization modes. Estimation for system tools virtualization technology effectiveness is given. Suggested technology is based on redirection of access requests to system objects shared among access subjects. Whole and partial system virtualization modes have been modeled. The difference between them is the following: in the whole virtualization mode all copies of access system objects are created whereon subjects’ requests are redirected including corresponding application objects;in the partial virtualization mode corresponding copies are created only for part of a system, for example, only system objects for applications. Alternative solutions effectiveness is valued relating to different attack scenarios. We consider proprietary and approved technical solution which implements system virtualization method for Microsoft Windows OS family. Administrative simplicity and capabilities of correspondingly designed system objects security tools are illustrated on this example. Practical significance of the suggested security method has been confirmed

Моделирование эволюции переплетенных вихревых нитей методом вихревых элементов

Research paper is devoted to the description of a new modification of the algorithm for calculating the vortex filaments motion. The results of methodological studies showing that this algorithm can correctly simulate the elongation, shortening, bending and reconnection of vortex filaments, as well as known qualitative phenomena arising from the vortex rings interaction are given. Particular attention is paid to the repetition of the calculation recently investigated experimentally the evolution of bound vortices. It is shown that with the developed algorithm can be steadily modeled complex vortex loops evolution. The main advantage of the new algorithm is stability and high-speed computing.Статья посвящена описанию новой модификации алгоритма расчета движения вихревых нитей. Представлены результаты методических исследований, показывающие, что данный алгоритм позволяет корректно моделировать растяжение, сжатие, изгиб и перезамыкание вихревых нитей, а также известные качественные явления, возникающие при взаимодействии вихревых колец. Особое внимание уделено повторению в расчете недавно исследованной экспериментально эволюции переплетенных вихрей. Показано, что с помощью разработанного алгоритма могут быть устойчиво смоделированы сложные эволюции вихревых петель. Главное достоинство нового алгоритма - устойчивость и высокая скорость вычислений

Анализ способов демпфирования колебаний крупногабаритной конструкций КА в магнитном поле земли

It is known that most of today's space vehicles comprise large antennas, which are bracket-attached to the vehicle body. Dimensions of reflector antennas may be of 30 ... 50 m. The weight of such constructions can reach approximately 200 kg.Since the antenna dimensions are significantly larger than the size of the vehicle body and the points to attach the brackets to the space vehicles have a low stiffness, conventional dampers may be inefficient. The paper proposes to consider the damping antenna in terms of its interaction with the Earth's magnetic field.A simple dynamic model of the space vehicle equipped with a large-size structure is built. The space vehicle is a parallelepiped to which the antenna is attached through a beam.To solve the model problems, was used a simplified model of Earth's magnetic field: uniform, with intensity lines parallel to each other and perpendicular to the plane of the antenna.The paper considers two layouts of coils with respect to the antenna, namely: a vertical one in which an axis of magnetic dipole is perpendicular to the antenna plane, and a horizontal layout in which an axis of magnetic dipole lies in the antenna plane. It also explores two ways for magnetic damping of oscillations: through the controlled current that is supplied from the power supply system of the space vehicle, and by the self-induction current in the coil. Thus, four objectives were formulated.In each task was formulated an oscillation equation. Then a ratio of oscillation amplitudes and their decay time were estimated. It was found that each task requires the certain parameters either of the antenna itself, its dimensions and moment of inertia, or of the coil and, respectively, the current, which is supplied from the space vehicle. In each task for these parameters were found the ranges, which allow us to tell of efficient damping vibrations.The conclusion can be drawn based on the analysis of tasks that a specialized control system can be used for damping vibrations of large-size antennas.  In this case the actuating elements can be coils. It is shown that efficient damping is possible when the certain system parameters are taken into consideration.Известно, что в состав многих современных космических аппаратов входят крупногабаритные антенны. Они крепятся к корпусу космического аппарата при помощи кронштейнов. Размеры рефлекторов антенн могут достигать 30…50 м. Масса таких конструкций может достигать около 200 кг.Поскольку габариты антенны существенно превосходят размеры корпуса космического аппарата и места крепление кронштейнов к корпусу имеют малую жесткость, обычные демпферы могут оказаться неэффективны. Предложено рассмотреть возможность демпфирования антенны за счет ее взаимодействия с магнитным полем Земли.Построена простейшая динамическая модель космического аппарата, оснащенного крупногабаритной конструкцией. Космический аппарат представляет собой параллелепипед, к которому с помощью балки крепится антенна.Для решения модельных задач принята упрощенная модель магнитного поля Земли: однородное, линии напряженности параллельны между собой и ориентированы перпендикулярно плоскости антенны.Рассматривались две схемы расположения катушки относительно антенны. Вертикальная схема, в которой ось магнитного диполя перпендикулярна плоскости антенны, и горизонтальная схема, в которой ось магнитного диполя лежит в плоскости антенны. Кроме компоновки исследовались два способа магнитного демпфирования колебаний: за счет управляемого тока, подаваемого от системы электропитания космического аппарата, и за счет самоиндукции тока в катушке. Таким образом, были сформулированы четыре задачи.В каждой задаче составлялось уравнение колебаний. После чего оценивалось отношение амплитуд колебаний и время их затухания. Оказалось, что для каждой задачи нужны определенные параметры, либо самой антенны, ее габаритные размеры и момент инерции, либо катушки и соответственно тока, который подается от космического аппарата. В каждой задаче для этих параметров были найдены диапазоны, при которых можно говорить о том, что демпфирование колебаний будет эффективным.На основе анализа задач можно сделать вывод о том, что для демпфирования колебаний крупногабаритной антенны может быть использована специализированная система управления. Исполнительными органами в этом случае могут быть катушки. Показано, что эффективное демпфирование возможно в том случае, если учитываются определенные параметры системы

PLM-COMPETENCE FORMATION USING COMPUTATIONAL-GRAPHICAL PRACTICE

The description of a new kind of learning activity “Computational - graphical practice” is presented. This practice aimed at consolidating the knowledge and skills acquired by students in the study of the basic engineering disciplines and bridge the gap in the training of students in the field of PLM-technology. The goals, objectives, program practices and competencies, which should have a student after passing the training practice, are liste

PLATE FOR SURGICAL TREATMENT FOUR-FRAGMENTAL FRACTURES OF THE PROXIMAL HUMERUS

We performed the analysis of proximal humerus fracture surgical treatment results. Reasons of unsatisfactory results of multifragmental fractures surgical reduction revealed. The new construction for multifragmental fractures fixation invented and patented. Our experiments proved this construction to increase the stability of humerus multifragmental fractures fixation

Measurement of the ratio of branching fractions BR(B0 -> K*0 gamma)/BR(Bs0 -> phi gamma)

The ratio of branching fractions of the radiative B decays B0 -> K*0 gamma and Bs0 -> phi gamma has been measured using 0.37 fb-1 of pp collisions at a centre of mass energy of sqrt(s) = 7 TeV, collected by the LHCb experiment. The value obtained is BR(B0 -> K*0 gamma)/BR(Bs0 -> phi gamma) = 1.12 +/- 0.08 ^{+0.06}_{-0.04} ^{+0.09}_{-0.08}, where the first uncertainty is statistical, the second systematic and the third is associated to the ratio of fragmentation fractions fs/fd. Using the world average for BR(B0 -> K*0 gamma) = (4.33 +/- 0.15) x 10^{-5}, the branching fraction BR(Bs0 -> phi gamma) is measured to be (3.9 +/- 0.5) x 10^{-5}, which is the most precise measurement to date.Comment: 15 pages, 1 figure, 2 table

Search for CP violation in D+→K−K+π+D^{+} \to K^{-}K^{+}\pi^{+} decays

A model-independent search for direct CP violation in the Cabibbo suppressed decay $D^+ \to K^- K^+\pi^+$ in a sample of approximately 370,000 decays is carried out. The data were collected by the LHCb experiment in 2010 and correspond to an integrated luminosity of 35 pb$^{-1}$. The normalized Dalitz plot distributions for $D^+$ and $D^-$ are compared using four different binning schemes that are sensitive to different manifestations of CP violation. No evidence for CP asymmetry is found.Comment: 13 pages, 8 figures, submitted to Phys. Rev.

Differential branching fraction and angular analysis of the decay B0→K∗0μ+μ−

The angular distribution and differential branching fraction of the decay B 0→ K ∗0 μ + μ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions

Measurement of the CKM angle γ from a combination of B±→Dh± analyses

A combination of three LHCb measurements of the CKM angle γ is presented. The decays B±→D K± and B±→Dπ± are used, where D denotes an admixture of D0 and D0 mesons, decaying into K+K−, π+π−, K±π∓, K±π∓π±π∓, K0Sπ+π−, or K0S K+K− final states. All measurements use a dataset corresponding to 1.0 fb−1 of integrated luminosity. Combining results from B±→D K± decays alone a best-fit value of γ =72.0◦ is found, and confidence intervals are set γ ∈ [56.4,86.7]◦ at 68% CL, γ ∈ [42.6,99.6]◦ at 95% CL. The best-fit value of γ found from a combination of results from B±→Dπ± decays alone, is γ =18.9◦, and the confidence intervals γ ∈ [7.4,99.2]◦ ∪ [167.9,176.4]◦ at 68% CL are set, without constraint at 95% CL. The combination of results from B± → D K± and B± → Dπ± decays gives a best-fit value of γ =72.6◦ and the confidence intervals γ ∈ [55.4,82.3]◦ at 68% CL, γ ∈ [40.2,92.7]◦ at 95% CL are set. All values are expressed modulo 180◦, and are obtained taking into account the effect of D0–D0 mixing