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991.
E. I. Gurin 《Measurement Techniques》1998,41(12):1146-1152
By analyzing the components of the instrumental error of vernier instruments, it is suggested that the action of this error
should be regarded as a displacement in time of the limits of the time intervals. Experimental data of an investigation of
the instrumental error of practical measuring instruments are presented.
Translated from Izmeritel'naya Tekhnika, No. 12, pp. 38–41, December, 1998. 相似文献
992.
993.
The aim this study was to report findings on the concentrations of mean triiodothyroxine (T3), thyroxin (T4), thyroid stimulating hormone (TSH) and prolactin (Prl) in patients with benign mastopathy and in control group. All of the examined subjects were clinically euthyroid. The mean T4 concentrations in women with mastopathy (78.25 +/- 15.27 ng/ml) were significantly lower than in control group 88.73 +/- 15.27). The mean TSH and PRL concentration in women with mastopathy were higher, but not significantly, than in control women. This results indicate, that benign mastopathy seems to be connected with thyroid functions. 相似文献
994.
995.
On the Finite-Time Stabilization of Uncertain Nonlinear Systems With Relative Degree Three 总被引:1,自引:0,他引:1
This technical note discusses a finite-time stabilization problem in a nonlinear, uncertain, environment. The main result of the present note is presented making reference to a triple integrator affected by bounded uncertainties and subject to ldquohardrdquo measurement nonlinearities such that the sign of the state variables is the only reliable information available for feedback. We propose a discontinuous control scheme guaranteeing the practical finite-time annihilation of the three state variables. Constructive proof and computer simulations, as well as guidelines for practical implementations, are provided throughout this technical note. 相似文献
996.
E. O. Adamov B. A. Gabaraev I. Kh. Ganev A. V. Dzhalavyan A. V. Lopatkin E. V. Murav’ev V. V. Orlov 《Atomic Energy》2007,103(1):490-500
The results of investigations performed by specialists at Research and Design Institute of Electrical Technology together
with other enterprises, institutes, and organizations concerning the formulation of a strategy for the development of nuclear
power in Russia in the first half of the 21st century are presented. The individual stages of the work, key assumptions, ideas,
and recommendations, on which the strategy is based, the initiatives which the President of the Russian Federation advanced
at the millennium summit held at the United Nations, and the international INPRO project initiated by Russia are examined.
It is concluded that innovative development and a transition to building as quickly as possible nuclear power objects that
meet the requirements and demands of the new century are necessary.
__________
Translated from Atomnaya énergiya,Vol. 103, No. 1, pp. 5–15, July, 2007. 相似文献
997.
998.
M.-C. Clochard T.L. Wade E. Balanzat 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,265(1):325-329
By combining low-energy ion irradiation with asymmetric etching, conical nanopores of controlled geometry can be etched in polycarbonate (PC). Cone bases vary from 0.5 to 1 μm. Top diameters down to 17 nm are reached. When etching from one side, the pH on the other side (bathed in neutral or acidic buffer) was monitored. Etching temperature ranged from 65 °C to 80 °C. Pore shape characterization was achieved by electro replication combined with SEM observation. The tip shape depended on whether an acidic buffer was used or not on the stopped side. 相似文献
999.
Martinez S. Bullo F. Cortes J. Frazzoli E. 《Automatic Control, IEEE Transactions on》2007,52(12):2214-2226
This paper analyzes a number of basic coordination algorithms running on synchronous robotic networks. We provide upper and lower bounds on the time complexity of the move-toward-average and circumcenter laws, both achieving rendezvous, and of the centroid law, achieving deployment over a region of interest. The results are derived via novel analysis methods, including a set of results on the convergence rates of linear dynamical systems defined by tridiagonal Toeplitz and circulant matrices. 相似文献
1000.
A. G. Radyuk A. E. Titlyanov E. M. Samedov 《Russian Journal of Non-Ferrous Metals》2007,48(3):227-230
The fabrication and properties of the surface layer on copper are investigated after deposition and thermal treatment of the aluminum gas-thermal coating. This process leads to the formation of a protective diffusion layer having high physical, mechanical, and performance characteristics. 相似文献