16,034 research outputs found
The support of the logarithmic equilibrium measure on sets of revolution in
For surfaces of revolution in , we investigate the limit
distribution of minimum energy point masses on that interact according to
the logarithmic potential , where is the Euclidean distance
between points. We show that such limit distributions are supported only on the
``out-most'' portion of the surface (e.g., for a torus, only on that portion of
the surface with positive curvature). Our analysis proceeds by reducing the
problem to the complex plane where a non-singular potential kernel arises whose
level lines are ellipses
An experimental study on (2) modular symmetry in the quantum Hall system with a small spin-splitting
Magnetic-field-induced phase transitions were studied with a two-dimensional
electron AlGaAs/GaAs system. The temperature-driven flow diagram shows the
features of the (2) modular symmetry, which includes distorted
flowlines and shiftted critical point. The deviation of the critical
conductivities is attributed to a small but resolved spin splitting, which
reduces the symmetry in Landau quantization. [B. P. Dolan, Phys. Rev. B 62,
10278.] Universal scaling is found under the reduction of the modular symmetry.
It is also shown that the Hall conductivity could still be governed by the
scaling law when the semicircle law and the scaling on the longitudinal
conductivity are invalid. *corresponding author:[email protected]: The revised manuscript has been published in J. Phys.: Condens.
Matte
Calculation of electrostatic fields using quasi-Green's functions: application to the hybrid Penning trap.
Penning traps offer unique possibilities for storing, manipulating and investigating charged particles with high sensitivity and accuracy. The widespread applications of Penning traps in physics and chemistry comprise e.g. mass spectrometry, laser spectroscopy, measurements of electronic and nuclear magnetic moments, chemical sample analysis and reaction studies. We have developed a method, based on the Green's function approach, which allows for the analytical calculation of the electrostatic properties of a Penning trap with arbitrary electrodes. The ansatz features an extension of Dirichlet's problem to nontrivial geometries and leads to an analytical solution of the Laplace equation. As an example we discuss the toroidal hybrid Penning trap designed for our planned measurements of the magnetic moment of the (anti)proton. As in the case of cylindrical Penning traps, it is possible to optimize the properties of the electric trapping fields, which is mandatory for high-precision experiments with single charged particles. Of particular interest are the anharmonicity compensation, orthogonality and optimum adjustment of frequency shifts by the continuous SternGerlach effect in a quantum jump spectrometer. The mathematical formalism developed goes beyond the mere design of novel Penning traps and has potential applications in other fields of physics and engineering
Low Power High Speed CMOS Interface for MOS Gas Sensors
AbstractA universal CMOS integrated MOS gas sensor interface for application development and sensor research is presented. Three different integrated heater sources with a maximum output range of 20V and 40mA and the possibility to operate an external transistor as current source with an output range of several hundred mA allow the operation of nearly all kinds of hotplates. Two different readout electronics for the sensor's resistance work within a range of 1 kΩ up to 10 MΩ with a constant voltage or constant current sensor bias. All measurements are digitized with two free configurable high speed low noise analog channels which allow fast and low power measurements. The configuration of the chip and the readout of the measurements are done with a register based SPI interface
Discovery and quantitative spectral analysis of an Ofpe/WN9 (WN11) star in the Sculptor spiral galaxy NGC 300
We have discovered an Ofpe/WN9 (WN11 following Smith et al.) star in the
Sculptor spiral galaxy NGC 300, the first object of this class found outside
the Local Group, during a recent spectroscopic survey of blue supergiant stars
obtained at the ESO VLT. The light curve over a five-month period in late 1999
displays a variability at the 0.1 mag level. The intermediate resolution
spectra (3800-7200 A) show a very close resemblance to the Galactic LBV AG Car
during minimum. We have performed a detailed non-LTE analysis of the stellar
spectrum, and have derived a chemical abundance pattern which includes H, He,
C, N, O, Al, Si and Fe, in addition to the stellar and wind parameters. The
derived stellar properties and the He and N surface enrichments are consistent
with those of other Local Group WN11 stars in the literature, suggesting a
similar quiescent or post-LBV evolutionary status.Comment: 9 pages, 4 figures, 2 tables. Accepted for publication in the
Astrophysical Journal Letter
Chandra HETGS Multi-Phase Spectroscopy of the Young Magnetic O Star theta^1 Orionis C
We report on four Chandra grating observations of the oblique magnetic
rotator theta^1 Ori C (O5.5 V) covering a wide range of viewing angles with
respect to the star's 1060 G dipole magnetic field. We employ line-width and
centroid analyses to study the dynamics of the X-ray emitting plasma in the
circumstellar environment, as well as line-ratio diagnostics to constrain the
spatial location, and global spectral modeling to constrain the temperature
distribution and abundances of the very hot plasma. We investigate these
diagnostics as a function of viewing angle and analyze them in conjunction with
new MHD simulations of the magnetically channeled wind shock mechanism on
theta^1 Ori C. This model fits all the data surprisingly well, predicting the
temperature, luminosity, and occultation of the X-ray emitting plasma with
rotation phase.Comment: 52 pages, 14 figures (1 color), 6 tables. To appear in the
Astrophysical Journal, 1 August 2005, v628, issue 2. New version corrects
e-mail address, figure and table formatting problem
James Webb Space Telescope (JWST): The First Light Machine
No abstract availabl
Reconciling the interests of the economic diversification participants in a single-industry town
Рассматриваются проблемы согласования интересов участников процесса диверсификации экономики моногорода в процессе управления развитием моногорода на основе реализации стратегии диверсификации. Целью исследования является разработка инструментов гармонизации интересов участников процесса диверсификации экономики моногорода на основе разработки модели полного согласования интересов и сопоставления ее с моделью отдельно взятого моногорода. Методы исследования: системный подход, анализ и синтез, построение множеств согласования интересов с применением диаграммы Эйлера-Венна, методы комбинаторики, построение экономических показателей и рядов динамики, графический метод представления результатов и построения иерархии согласования интересов. Результаты исследования. Представлена модель полного согласования интересов различных групп лиц, в которой отражены сферы возможного пересечения интересов, а также иерархия числа согласуемых интересов. Предложены основные группы участников процесса диверсификации моногорода, а также разграничено понятие участника и роли (функции) участника в данном процессе. Обосновано и определено число множеств в зависимости от числа участников, чьи интересы одновременно согласуются, на примере моногорода Калтан Кемеровской области. На основе предложенной модели построена модель согласования интересов на примере моногорода Калтана. Полученная модель имеет трапециевидную форму, что свидетельствует о достаточно небольшом числе общих согласуемых интересов. Автор приходит к выводу, что в моногороде сформирован треугольник интересов «администрация города - малый бизнес в роли инвестора - вуз», представляющий основу в иерархии согласования интересов моногорода Калтан. Центральное положение при согласовании интересов с прочими участниками занимает исключительно администрация города. На основе данных выводов внесены предложения по направлениям дальнейшего согласования интересов на примере рассматриваемого моногорода.The article explores the problems of reconciling the interests of single-industry towns, a need that arises from the entire process of industry development management through a diversification strategy. The aim of this study is to develop tools to harmonize the interests of the single-industry towns, based on a model of full harmonization with the model of an individual single-industry town. Methods of the research: system approach, analysis and synthesis, building a set of harmonized interests with the application of the Eulerian-Venn diagram, combinatorics methods, construction of economic indicators and series of dynamics, graphical method of presentation of results and building the hierarchy of interests. Results of the study. The paper introduces the model for fully reconciling the interests of different groups of persons, reflecting the areas of possible intersecting interests and the hierarchy of the number of interests involved. The article proposes the main groups of participants in the diversification process and the differentially concept of participant and the role (function) of the participant in the diversification process. The author justifies and estimates the number of sets depending on the number of participants whose interests are concurrently reconciled in Kaltan case study. The proposed model is used for Kaltan, Kemerovo region case study. The result ing model is of a trapezoidal form, which indicates that there are quite a few common consenting interests. The author concludes that a triangle of interests «city administration - small business as investor - university» is formed. This triangle represents the highest level of harmonization of interests in the hierarchy. The city administration is in central position in reconciling interests with other participants. By the example of the considered single-industry town and based on these findings the suggestion on further harmonization of interests was made
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