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排序方式: 共有2233条查询结果,搜索用时 15 毫秒
51.
A. A. Lempert D. N. Sidorov A. V. Zhukov G. L. Nguyen 《Automation and Remote Control》2016,77(11):1883-1893
We propose an approach for solving the task prioritization problem in road surface repair under bounded resources; the idea is to use a combination of defect recognition and classification methods based on statistical analysis and machine learning (random forests) with original methods for solving infinite-dimensional optimization problems (optical-geometric analogy). We show the results of a computational experiment that indicate high performance of the developed algorithms, and the resulting solutions were evaluated highly by experts in road facilities management. Our results may encourage more efficient use of resources to improve the quality of motorways. 相似文献
52.
BM Mytskan BV Shchutka VA Shakhlamov MA Mytskan 《Canadian Metallurgical Quarterly》1993,116(8):208-210
Under increased muscular activity in some muscular fibers disintegration areas of myofibrillar apparatus has been revealed. Migration of myonuclei into these microregions starts the mechanism of their segregation due to plasmolemma produced from the reticulum sarcoplasmaticum and triad systems surface. After plasmolemma production in "sarcocytes" intensive development and differentiation of organellae occur. As a result of differentiation "sarcocytes" transform in to myosatellitocytes of type-2 and migrate under lamina externa muscular fibers. So, a hypothesis about formation of myogenic tissue's cellular phase from the myosymplastic one has been confirmed. 相似文献
53.
GM Roshchina EB Lishnevskaia IA Sizova VA Orlova IM Tereshin 《Canadian Metallurgical Quarterly》1980,25(11):850-854
The technique of accumulating preparation of the mucosa and "turned out sac" was used to show that levorin, a polyenic antibiotic in a concentration of 10(-6) M, lowered the transport rate and accumulation of glucose by the epithelial cells of the rat thin intestine under conditions of oxygenation. Suppression of the glucose transport in the first stages resulted in partial inhibition of the transmembrane transfer. It is suggested that levorin suppression of the glucose transport through the erythrocyte apical membrane in the thin intestine is associated with a decrease in the electrochemical gradient of Na+. 相似文献
54.
V. S. Sidorov 《Journal of Engineering Physics and Thermophysics》1981,41(3):1032-1035
An analytical solution of the thermal conductivity problem with boundary conditions of the third kind and arbitrary coordinate and time dependence of the Biot number is found in the form of a converging series of quadratures.Notation , z
dimensionless coordinates
-
dimensionless temperature
- Q
dimensionless volume heat-liberation density per unit time
- Fo=/2
Fourier number
- Bi1(, Fo)=(, Fo) · /
Biot number
-
thermal diffusivity coefficient
-
plate thickness
-
time
- (, Fo)
heat-liberation coefficient
-
thermal conductivity coefficient
- i
summation index
- Jo
zero order Bessel function of the first kind
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 41, No. 3, pp. 536–540, September, 1981. 相似文献
55.
beta-Ionone is found to stimulate considerably carotinoids synthesis in Blakeslea trispora. The stabilization of carotene-synthesizing ability of B. trispora in the presence of beta-ionine under prolonged incubation time is observed. Stabilization of polyribosomes in the presence of beta-ionine is observed when studying polyribosome content in B. trispora. A hypothesis is expressed on the existence of biochemical "receptors" as a linkage between synthesized protein and destroying mRNA. 相似文献
56.
VA Belitser TV Varetskaia SN Tsynkalovskaia LA Tsariuk LI Shevchenko 《Canadian Metallurgical Quarterly》1976,48(4):521-532
A new diagnostic method to determine fibrinogen and fibrin splitting products is based on the fact that high-molecular fragments acting as specific inhibitors of fibrin self-assembly compose these products. Fibrinogen and fibrin splitting products are detected and determined quantitatively by prolongation of coagulation time in the test with the standard monomeric fibrin. The number of units of anticoagulating activity in the studied urine are the results of the determinations. Sensitivity of the method if necessary may be increased by adding of a certain amount of the fibrinogen and fibrin splitting products to the test that makes a favourable background for the action of the products. The method is rather sensitive, reliable and simple. It may be used in ordinary clinical laboratories. The method proved to be quite satisfactory when testing renal diseases at the clinic. It is of great significance for early detection of the transplanted kidney rejection. The new method is compared with the known immunological method which consist in determination of the inhibitory effect of the fibrinogen and fibrin splitting products on agglutination of erythrocytes of specific antibodies; the erythrocytes being subjected to "tanning" and "loading" with fibrinogen. A satisfactory correlation is found between the results of two methods. 相似文献
57.
E. A. Ekimov V. A. Sidorov A. V. Rakhmanina N. N. Mel’nik M. A. Timofeev R. A. Sadykov 《Inorganic Materials》2006,42(11):1198-1204
Microcrystalline boron-doped diamond powders consisting of octahedrally faceted crystals have been synthesized in the C-H-B system at a pressure of 8 GPa and temperatures above 2000 K. The presence of boron has been shown to reduce the parameters of diamond synthesis compared to the binary system C-H (naphthalene). One possible reason for the reduction in synthesis parameters is the formation of less perfect graphite in the boron system in an intermediate step of diamond synthesis. At B/(C + B) ratios of about 5–10 at % in the C-H-B (naphthalene + boron) system, superconducting diamond microcrystals have been synthesized. 相似文献
58.
The results of experiments on the nonlinear optical confinement of microsecond pulses of CO2 laser radiation in a composite material comprising a potassium iodide matrix containing dispersed silver chloride nanoparticles coated by an island film of metallic silver are presented. The energy threshold for the laser radiation confinement is 15 mJ/cm2 and the dynamic range of confinement amounts to 103. 相似文献
59.
60.
Albagachiev A. Yu. Stavroskii M. E. Sidorov M. I. 《Journal of Machinery Manufacture and Reliability》2020,49(1):57-63
Journal of Machinery Manufacture and Reliability - This article discusses wear-preventive tribological coatings that increase the operational life of artillery, tank, and rifle barrels. Studies... 相似文献