Technologies for the Disabled

Nowadays computers have taken the dominant role in our society.Most jobs now require access to computers and the Internet. But what happens if a person is blind, deaf or physically disabled? The latest technologies are designed to help them use computers, do their jobs in the office, attend school and university or interact with their families at home. Technologies offers many different ways that can lead to normal life for those people. Computers helpthe disabled people get what they want more than anything else - independence. Devices that help them to perform any activity are called assistive technology

Soil factors of resistance of spruce forest.

Spruce (Picea abies (L.) H. Karst.) is one of the major coniferous species represented in Moscow region. It grows on loam or clay loam soils and it is sensitive to soil moisture. The drought of 2010 adversely affected spruce forest. Weak spruce is further highly influenced by various pathogens and pests, among which the most aggressive is bark beetle (Ips Typographus L.). Many researchers have investigated the role of climatic fluctuations in respect of the development of pathogens; however, soil and hydrological factors are often out of the focus. The aim of our work was to study the soil factors affecting the state and resistance of spruce stands. The object of the study was spruce stands of the Moscow educational-experimental forest unit. Forest inventory data in combination with satellite imagery in a GIS environment allowed us to discover a plot with alive resistant spruce surrounded by dead spruce stands of the same age. During field surveys, we investigated soil in both alive and died spruce plots. The study showed that alive spruce forest has developed on soil with specific alternation of horizons of different texture (contains sand layer of varying thickness, underlain by loam horizons). The surrounding soils with dead spruce do not have such a sandy layer. The combination of layers with different texture support accumulation of soil moisture. This moisture, which is trapped by capillary forces in the small pore layer of the soil. Most probably, the ability of soil to store more water has allowed spruce to survive during the drought. We plan to continue our research and investigate more plots with alive spruce stands, to prove our hypothesis

Пинг-понговая дипломатия: влияние на установление китайско-американских отношений

The relevance of the study is determined by the role and place of sports diplomacy in international relations and foreign policy today. Sport is truly a global phenomenon. In the modern world, it is a tool of political influence with the greatest potential and opportunities. History abounds in examples of how different countries used this tool to realize their goals. The “pingpong diplomacy” confirms this fact, since it was a breakthrough in US-China relations. Thanks to the efforts of the PRC StateАктуальность темы исследования определяется ролью и местом спортивной дипломатии в международных отношениях и внешней политике. Спорт - явление глобального масштаба. В современном мире он является инструментом политического воздействия с мощнейшим потенциалом и возможностями. История знает немало примеров того, как разные страны использовали этот инструмент для реализации поставленных целей. Подтверждением этому является «дипломатия пинг-понга», которая явилась прорывом в американо-китайских отношениях. Благодаря усилиям премьера Госсовета КНР Чжоу Эньлая и госсекретаря США Генри Киссинджера в отношениях Пекина и Вашингтона удалось установить доверие в 1971 г., а в 1979 г. и дипломатические отношения. Это, в свою очередь, способствовало изменению геополитической ситуации в отношениях США - КНР - СССР: упрочило положение США и Китая и ослабило позиции СССР. Предметом исследования статьи является спортивная дипломатия, ее особый случай - «дипломатия пинг-понга», сыгравшая решающую роль в нормализации отношений между КНР и США и их последующем развитии. В данном исследовании авторы применили принципы историзма и объективности, которые предполагают рассмотрение явлений в динамике их изменения, закономерном историческом развитии. Был использован историко-генетический метод исследования, суть которого состоит в последовательном раскрытии свойств, функций и изменений изучаемой реальности в процессе ее исторического движения. По итогам исследования авторы делают вывод, что пинг-понговая дипломатия оказала значительное влияние на установление дипломатических отношений между двумя державами - КНР и США, а также в дальнейшем способна оказывать положительное воздействие на развитие двусторонних отношений, преодоление проблем и конфликтов между сторонами

Hyperfine structure of the ground state muonic He-3 atom

On the basis of the perturbation theory in the fine structure constant $\alpha$ and the ratio of the electron to muon masses we calculate one-loop vacuum polarization and electron vertex corrections and the nuclear structure corrections to the hyperfine splitting of the ground state of muonic helium atom $(\mu\ e \ ^3_2He)$. We obtain total result for the ground state hyperfine splitting $\Delta \nu^{hfs}=4166.471$ MHz which improves the previous calculation of Lakdawala and Mohr due to the account of new corrections of orders $\alpha^5$ and $\alpha^6$. The remaining difference between our theoretical result and experimental value of the hyperfine splitting lies in the range of theoretical and experimental errors and requires the subsequent investigation of higher order corrections.Comment: Talk on poster section of XXIV spectroscopy congress, 28 February-5 March 2010, Moscow-Troitsk, Russia, 21 pages, LaTeX, 8 figure

Cooled ferromagnetic shield as a part hybrid system for isolation of a flux qubit from electromagnetic environment

Currently, circuits for quantum informatics, communications and measuring equipment containing superconducting flux qubits in a planar design are being created by quantum engineering techniques. To function, such structures must be cooled in a refrigerator down to about 10 mK. The flux qubits have linear size of superconducting circuit of some tens of micrometers and are very sensitive to external magnetic fields and their variations.  The qubit built in the gradiometer-like design has reduced sensitivity to external uniform magnetic fields, but remains quite sensitive to their variations. To protect the qubit from unwanted external magnetic fields, which include the Earth's field, man-made fields, and residual magnetic fields of the cryostat parts, it is necessary to create efficient magnetic shields. Earlier, we proposed a scheme for a single-photon microwave counter, in which a planar flux qubit in a gradiometer version serves as the receiving element. To let it function properly, a 3-layer hybrid magnetic shield composed of two superconducting and one ferromagnetic cylinders, has been designed for installation in a dilution refrigerator at 10 mK temperature. The effectiveness of such a shield depends on the correct design of all three shells. This paper presents the results of calculation and magnetic measurements of a cylindrical ferromagnetic screen made of low-temperature permalloy Cryoperm 10 in dc and low-frequency alternating magnetic fields. Cryoperm 10 keeps high magnetic permeability at liquid helium temperatures and below. It is shown that this shield is able of reducing the absolute value of the magnetic field and its variations by 55-70 dB. Together with superconducting lead magnetic shields, this design will reduce the absolute value of the field by 70 dB, and the field variation by 200 dB, which will provide the necessary conditions for the operation of a single-photon counter based on a flux qubit

Weak decays of the B_c meson to charmonium and D mesons in the relativistic quark model

Semileptonic and nonleptonic decays of the B_c meson to charmonium and D mesons are studied in the framework of the relativistic quark model. The decay form factors are explicitly expressed through the overlap integrals of the meson wave functions in the whole accessible kinematical range. The relativistic meson wave functions are used for the calculation of the decay rates. The obtained results are compared with the predictions of other approaches.Comment: 27 pages, 17 figures, 1 figure and 1 reference added, version to appear in Phys. Rev.

Relativistic Description of Exclusive Semileptonic Decays of Heavy Mesons

Using quasipotential approach, we have studied exclusive semileptonic decays of heavy mesons with the account of relativistic effects. Due to more complete relativistic description of the $s$ quark more precise expressions for semileptonic form factors are obtained. Various differential distributions in exclusive semileptonic decays of heavy mesons are calculated. It is argued that consistent account of relativistic effects and HQET motivated choice of the parameters of quark-antiquark potential allow to get reliable value for the ratio $A_2(0)/A_1(0)$ in the $D\to K^*l\nu_l$ decay as well as the ratio~$\Gamma(D\to K^*l\nu_l)/\Gamma(D\to Kl\nu_l)$. All calculated branching ratios are in accord with available experimental data.Comment: 18 pages, LATEX, 2 figures inclosed + 4 Postscript figure

Properties of heavy quarkonia and B_c mesons in the relativistic quark model

The mass spectra and electromagnetic decay rates of charmonium, bottomonium and B_c mesons are comprehensively investigated in the relativistic quark model. The presence of only heavy quarks allows the expansion in powers of their velocities. All relativistic corrections of order v^2/c^2, including retardation effects and one-loop radiative corrections, are systematically taken into account in the computations of the mass spectra. The obtained wave functions are used for the calculation of radiative magnetic dipole (M1) and electric dipole (E1) transitions. It is found that relativistic effects play a substantial role. Their account and the proper choice of the Lorentz structure of the quark-antiquark interaction in a meson is crucial for bringing theoretical predictions in accord with experimental data. A detailed comparison of the calculated decay rates and branching fractions with available experimental data for radiative decays of charmonium and bottomonium is presented. The possibilities to observe the currently missing spin-singlet S and P states as well as D states in bottomonium are discussed. The results for B_c masses and decays are compared with other quark model predictions.Comment: 31 pages, 2 figures, minor correction

Properties of 15Cr12WNiMoV steel after vacuum activated chromium plating of its surface

In this work, we studied the properties of samples from steel 15Cr12WNiMoV after vacuum activated chromium plating at temperatures of 1070 and 1100 °C for 4 and 10 h. It was found that after chemical-thermal treatment on the samples a diffusion layer with a thickness of 50 to 130 µm is formed, consisting of 56…82 wt.% of chromium, the rest is iron. Metallographic studies were carried out on the samples and tests for heat resistance were carried out at a temperature of T = 900 °C. It was found that chrome-plated samples significantly exceed the initial samples and nitrided ones in terms of heat resistance. Tests of samples for tensile strength after chromium plating showed a significant increase in strength indicators for ultimate strength and yield strength. The plasticity characteristics of these samples are reduced.Проведені дослідження властивостей зразків зі сталі 15Х12ВНМФ після вакуумного активованого хромування при температурах 1070 і 1100 °С протягом 4 і 10 год. Установлено, що після хіміко-термічної обробки на зразках формується дифузійний шар товщиною від 50 до 130 мкм, що складається з 56…82 ваг.% хрому, інше – залізо. На зразках були проведені металографічні дослідження й здійснені випробування на жаростійкість при Т = 900 °С. Установлено, що хромовані зразки по жаростійкості значно перевершують вихідні зразки й азотовані. Проведені випробування зразків на міцність на розрив після хромування показали істотне збільшення міцностних показників для межі міцності й межі текучості. Характеристики пластичності цих зразків зменшуються.Проведены исследования свойств образцов из стали 15Х12ВНМФ после вакуумного активированного хромирования при температурах 1070 и 1100 °С в течение 4 и 10 ч. Установлено, что после химикотермической обработки на образцах формируется диффузионный слой толщиной от 50 до 130 мкм, состоящий из 56…82 вес.% хрома, остальное – железо. На образцах были проведены металлографические исследования и осуществлены испытания на жаростойкость при Т = 900 °С. Установлено, что хромированные образцы по жаростойкости значительно превосходят исходные образцы и азотированные. Проведенные испытания образцов на прочность на разрыв после хромирования показали существенное увеличение прочностных показателей для предела прочности и предела текучести. Характеристики пластичности этих образцов уменьшаются