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Shumski A.,Training Center
ICETA 2013 - 11th IEEE International Conference on Emerging eLearning Technologies and Applications, Proceedings | Year: 2013

This article highlights Cisco Academy operation experience in multivendor non-government training centre. Article covers analysis of the role Cisco Academy plays in business of the centre which offers short term courses of different vendors as well as academic education programs. © 2013 IEEE.

Momcilovic M.,University of Belgrade | Kovacevic J.,Geological Institute of Serbia | Tanic M.,Training Center | Crossed D Signorcrossed D Signevic M.,University of Nis | And 2 more authors.
Environmental Monitoring and Assessment | Year: 2013

The activity concentrations of natural radionuclides in soils from the area affected by uranium mining at Stara Planina Mountain in Serbia were studied and compared with the results obtained from an area with no mining activities (background area). In the affected area, the activity concentrations ranged from 1.75 to 19.2 mg kg-1 for uranium and from 1.57 to 26.9 mg kg -1 for thorium which is several-fold higher than those in the background area. The Th/U, K/U, and K/Th activity ratios were also determined and compared with data from similar studies worldwide. External gamma dose rate in the air due to uranium, thorium, and potassium at 1 m above ground level in the area affected by uranium mining was found to be 91.3 nGy h-1, i.e., about two-fold higher than that in background area. The results of this preliminary study indicate the importance of radiological evaluation of the area and implementation of remedial measures in order to prevent further dispersion of radionuclides in the environment. © 2012 Springer Science+Business Media B.V.

Duan W.,CAS Institute of Atmospheric Physics | Luo H.,Training Center
Advances in Atmospheric Sciences | Year: 2010

There are three common types of predictability problems in weather and climate, which each involve different constrained nonlinear optimization problems: the lower bound of maximum predictable time, the upper bound of maximum prediction error, and the lower bound of maximum allowable initial error and parameter error. Highly efficient algorithms have been developed to solve the second optimization problem. And this optimization problem can be used in realistic models for weather and climate to study the upper bound of the maximum prediction error. Although a filtering strategy has been adopted to solve the other two problems, direct solutions are very time-consuming even for a very simple model, which therefore limits the applicability of these two predictability problems in realistic models. In this paper, a new strategy is designed to solve these problems, involving the use of the existing highly efficient algorithms for the second predictability problem in particular. Furthermore, a series of comparisons between the older filtering strategy and the new method are performed. It is demonstrated that the new strategy not only outputs the same results as the old one, but is also more computationally efficient. This would suggest that it is possible to study the predictability problems associated with these two nonlinear optimization problems in realistic forecast models of weather or climate. © 2010 Chinese National Committee for International Association of Meteorology and Atmospheric Sciences, Institute of Atmospheric Physics, Science Press and Springer-Verlag Berlin Heidelberg.

Chen Z.,Henan University | Tian Y.,Training Center | Li S.,Henan University | Zheng H.,Henan University | Zhang W.,Henan University
Journal of Alloys and Compounds | Year: 2012

Arborous structure SnO 2 porous films were electrodeposited on Ti substrate using pulse-potential technique. The deposition process of SnO 2 was investigated through cyclic voltammetry, potentiostatic electrolysis and chronoamperometry. It was found that SnO 2 and metallic Sn were codeposited under the low pulse potential (-0.6 V vs. Ag/AgCl). The electrodeposited Sn was anodic oxidized under the subsequent high pulse potential (-0.1 V vs. Ag/AgCl). The formation of SnO 2 possessed an instantaneous nucleation process. Dye-sensitized solar cells were fabricated using the electrodeposited SnO 2 porous films. The photo-electricity conversion efficiency was about 0.47%. © 2011 Elsevier B.V. All rights reserved.

Zhang D.-L.,Chinese Academy of Meteorological Sciences | Zhang D.-L.,University of Maryland University College | Lin Y.,Chinese Academy of Meteorological Sciences | Zhao P.,Chinese Academy of Meteorological Sciences | And 4 more authors.
Geophysical Research Letters | Year: 2013

The heaviest rainfall in 6 decades fell in Beijing on 21 July 2012 with a record-breaking amount of 460 mm in 18 h and hourly rainfall rates exceeding 85 mm. This extreme rainfall event appeared to be reasonably well predicted by current operational models, albeit with notable timing and location errors. However, our analysis reveals that the model-predicted rainfall results mainly from topographical lifting and the passage of a cold front, whereas the observed rainfall was mostly generated by convective cells that were triggered by local topography and then propagated along a quasi-stationary linear convective system into Beijing. In particular, most of the extreme rainfall occurred in the warm sector far ahead of the cold front. Evidence from a cloud-permitting simulation indicates the importance of using high-resolution cloud-permitting models to reproduce the above-mentioned rainfall-production mechanisms in order to more accurately predict the timing, distribution, and intensity of such an extreme event. Key Points Local terrain and echo-training are the causes for the extreme rainfall event High resolution cloud resolving models can predict this extreme rainfall event Operational models provided right guidance but for wrong reasons ©2013 American Geophysical Union. All Rights Reserved.

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