Influence of Intra-cell Traffic on the Output Power of Base Station in GSM

In this paper we analyze the influence of intracell traffic in a GSM cell on the base station output power. It is proved that intracell traffic increases this power. If offered traffic is small, the increase of output power is equal to the part of intracell traffic. When the offered traffic and, as the result, call loss increase, the increase of output power becomes less. The results of calculation are verified by the computer simulation of traffic process in the GSM cell. The calculation and the simulation consider the uniform distribution of mobile users in the cell, but the conclusions are of a general nature

Management Measures in Brown Hare Population in Various Habitats in Serbia

Brown hare in Serbia lives in various habitats although the best brown hare habitats are lowland areas and river valleys. Brown hare has successfully adapted to agroecosystems in agricultural areas. In the last two decades in Serbia a number of studies was conducted associated with the analysis of themanagement measures in brown hare population, which recorded some cyclic oscillations in population abundance, density,age structure and exploitationrate. These measures are key elements in management of wildlife population so their implementation should be enforced. Problems related to brown hare population management in Serbia arise because there are neither proper guidelines to determine hare hunting productive areas nor how to define the solvency and capacities of hunting grounds that are not adapted to newly created habitat conditions in certain hunting grounds. Methodology of conducting and defining the number of hare population in various types of hunting grounds does not match given habitat conditions. Taking into account various habitat conditions in hunting grounds of Vojvodina and central Serbia it is very important to define in a correct manner population spring abundance, population density, age structure and exploitation rate for the purpose of sustainable management in hare population

OLEDs with enhanced high temperature operational stability

Temperature dependence of electroluminescence degradation is studied in organic light emitting devices containing an emitting layer composed of a mixture of different hole transport molecules and tris(8-hydroxyquinoline)aluminum (AlQ(3)) electron transport and emitter molecule. The emitting layer is sandwiched between hole and electron transport layers. Devices containing the hole transport molecule N,N'-di(naphthalene-1-yl)-N,N'-diphenyl-benzidine (NPB), doped with quinacridone (DMQ) green emitter showed remarkable temperature stability. For these devices, a half-life of about 78,500 hours, 18,700 hours, and 8,600 hours can be projected for operating temperatures of 22degreesC, 700degreesC and 100degreesC, respectively, at an initial device luminance of 100 cd/m(2). Activation energies for device degradation were determined for devices with different hole transport molecules and it was found that devices with higher activation energy show better high temperature stability. These results are consistent with the recently proposed degradation mechanism based on the unstable cationic AlQ(3) species

Millimeter and submillimeter wave technology developments for the next generation of fusion devices

There is increasing demand for compact watt-level coherent sources in the millimeter and submillimeter wave region. The approach that we have taken to satisfy this need is to fabricate two-dimensional grids loaded with oscillators, electronic beam steerers, and frequency multipliers for quasioptical coherent spatial combining of the outputs of a large number of low-power devices

Screening of drought oxidative stress tolerance in Serbian melliferous plant species

This study was designed to examine and compare antioxidant and free-radical scavenging activities of leaves of six different melliferous plant species (Populus alba, Robinia pseudoacacia, Sophora japonica, Euodia hupehensis, Tilia sp., Fraxinus sp.) from Serbia in order to evaluate their drought oxidative stress tolerance. Experiment was conducted during June, July and August. In this study, we reported the results concerning proline accumulation, soluble protein content, quantities of malonyldialdehyde,total antioxidant capacity determined by FRAP method and scavenger activity determined by DPPH method. According to our results, all melliferous plant species were subjected to drought oxidative stress during July when soil humidity decreased. During July, proline content and MDA quantity increased and soluble proteins decreased in all investigated species. High and permanent antioxidant activity during the whole investigated period was observed in P. alba, but insufficient to protect itsleaves from oxidative injury during the period of drought in July. The highest ability to accumulate proline and highest protein content under severe drought stress in July was observed in Fraxinus sp. Other investigated antioxidant parameters (total antioxidant and DPPH radical scavenger capacities) were high and accumulation of MDA was low which indicate high drought oxidative stress tolerance. Therefore, highest ability to adapt under severe drought stress and highest drought oxidative stresstolerance were observed in Fraxinus sp.Key words: Melliferous trees, lipid peroxidation, DPPH, FRAP, proline accumulation

Lattice dynamics of FeSb2

The lattice dynamics of FeSb2 is investigated by the first-principles DFT calculations and Raman spectroscopy. All Raman and infra-red active phonon modes are properly assigned. The calculated and measured phonon energies are in good agreement except for the B3g symmetry mode. We have observed strong mixing of the Ag symmetry modes, with the intensity exchange in the temperature range between 210 K and 260 K. The Ag modes repulsion increases by doping FeSb2 with Co. There are no signatures of the electron-phonon interaction for these modes

Influence of antiferromagnetic spin ordering on the far-infrared active optical phonon modes of alpha-MnSe

The effects of spin-phonon interaction and magnetic anisotropy on the temperature dependence of the infrared optical phonon modes in the antiferromagnetic alpha-MnSe are investigated by use of Green’s function formalism within 1/z perturbation framework. The renormalization effects are calculated explicitly as a function of temperature, phonon-phonon, and spin-phonon interaction constants. Temperature dependence of the renormalized LO phonon frequencies of the F1u infrared active and combinational phonon modes are calculated and compared with experimental data. We have shown that the inclusion of anisotropy is necessary in order to get a good quantitative agreement with the experiment

An Integrated Circuit for Signal Processing of the AMS RICH Photmultipliers Tubes

An analog integrated circuit has been designed, in a BiCMOS 0.8 micron technology, for the feasability study of the signal processing of the AMS RICH photomultiplier tubes. This low power, three channel gated integrator includes its own gate and no external analog delay is requiered. It processes PMT pulses over a dynamic range of more than 100. A logic output that indicates whether the analog charge has to be considered is provided. This gated integrator is used with a compact DSP based acquisition system in a 132 channels RICH prototype. The charge calibration of each channel is carried out using a LED. The pedestal measurement is performed on activation of a dedicated input. The noise contribution study of the input RC network and amplifiers is presented.Comment: IEEE symp. on Nucl. Sci. and Med. Imaging, Toront

The Path Integral Monte Carlo Calculation of Electronic Forces

We describe a method to evaluate electronic forces by Path Integral Monte Carlo (PIMC). Electronic correlations, as well as thermal effects, are included naturally in this method. For fermions, a restricted approach is used to avoid the ``sign'' problem. The PIMC force estimator is local and has a finite variance. We applied this method to determine the bond length of H$_2$ and the chemical reaction barrier of H+H$_2\longrightarrow$H$_2$+H. At low temperature, good agreement is obtained with ground state calculations. We studied the proton-proton interaction in an electron gas as a simple model for hydrogen impurities in metals. We calculated the force between the two protons at two electronic densities corresponding to Na ($r_s=3.93$) and Al ($r_s=2.07$) using a supercell with 38 electrons. The result is compared to previous calculations. We also studied the effect of temperature on the proton-proton interaction. At very high temperature, our result agrees with the Debye screening of electrons. As temperature decreases, the Debye theory fails both because of the strong degeneracy of electrons and most importantly, the formation of electronic bound states around the protons.Comment: 18 pages, 10 figure