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981.
V. G. Rifert Yu. V. Putilin V. L. Podbereznyi 《Journal of Engineering Physics and Thermophysics》1988,54(5):490-492
Experimental data are presented for the local heat liberation coefficient for flow of a liquid film on a smooth horizontal tube, permitting refinement of the concept of the heat exchange mechanism.Notation , , ,a
kinematic viscosity, thermal conductivity, density, and thermal diffusivity of liquid
-
liquid film thickness
-
irrigation density
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 54, No. 5, pp. 736–739, May, 1988. 相似文献
982.
V. P. Trushechkin Yu. A. Balashov V. S. Senin V. V. Podnebesnov 《Strength of Materials》1988,20(4):422-425
1. | The combined theoretical and experimental investigation of the thermal and stress state of the nozzle vane of a gas turbine confirmed the possibility of using the newly devised experimental strain gauges in the range of working temperatures 293–973°K. |
2. | In modeling the pin system of the outlet channel by thin continuous baffles we obtained satisfactory agreement of calculation and experiment at all points of measurement uniformly distributed over the surface of the vane. |
983.
This paper describes the synthesis and cation-radical polymerization of 1,5-bis(1-naphthoxy)-3-oxapentane. This monomer contains a flexible diethylene oxide unit between two 1-naphthalene rings. The FT-IR analysis of the resulted polymer indicates that it contains 1,4-disubstituted naphthalene structural units, i.e. 4,4-disubstituted-1,1-binaphthalene units. The polymer is crystalline with a melting point of 236 °C.Part IX: V. Percec and J. H. Wang: J. Mater. Chem., in press 相似文献
984.
I. N. Razuvaeva V. N. Kopylov N. M. Dobrodeeva G. V. Medvedeva Yu. D. Khesin 《Metal Science and Heat Treatment》1992,34(1):57-63
1. | Deformation of pseudo--alloy in the upper part of the (+)-region (from tm to tp.t –50°C) which provides occurrence of dynamic recrystallization independent of the deformation scheme leads to preparation of a multicomponent texture. Here the structure consists of recrystallized -grains with a lamellar intergranular structure and individual round -grains with toothed boundaries. This structure provides quasi-anisotropy of properties in the plane of the sheet, and also high and isotropic values for corrosion-mechanical strength. |
2. | Deformation in the lower part of the (+)-region (from tp.t –100°C to tp.t –150°C), which does not provide occurrence of dynamic recrystallization processes, leads independent of the deformation scheme to preparation either of a predominantly prismatic texture, or a texture of the inclined basal type with a structure consisting mainly of -phase plates. In alloy with this texture and a predominantly prismatic texture marked anisotropy of strength properties and a reduction in low-cycle fatigue endurance in a corrosive medium is observed for transverse specimens. |
985.
I. E. Mikhailov Yu. V. Polikarpov A. K. Fink 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(11):724-727
1. | The installation of a conical transitional segment between a tower (shaft)-type water intake-outlet and penstock affects a significant reduction in head loss in the pump mode, but has virtually no effect on the magnitude of the latter in the pump mode. |
2. | The existence of a conical transitional element in the pump mode appreciably lowers the discharge velocities of the flow and increases the effective height of the water-passing openings by 1.5–1.7 times when the height of the intake openings h0.5dp. |
3. | The head losses in the intake-outlet decrease in the pump mode of operation with increasing degree of expansion of the transitional diffusor segment. |
986.
提出并研制成一种新型硅三端负阻器件。该器件由一n沟耗尽型MOS管、一横向pnp双极晶体管和一个电阻集成而得。它具有“双负阻”特性和正阻区阻值易于控制等特点。由理论计算出的器件I_c—V_(CB)特性和负阻参数与实验结果符合良好。 相似文献
987.
A. P. Gurin V. P. Mikhailov Yu. A. Bagdasarov 《Soil Mechanics and Foundation Engineering》1992,29(2):58-62
Results are presented for tests on 27 foundations in punched (tamped-out) trenches (including some tested under repeated loading and when a long period had elapsed after their construction), which showed high technical-economic indices. Experience with their operation permits recommending wider use of this foundation construction method.Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 2, pp. 18–21, March–April, 1992. 相似文献
988.
曝光数据流优化问题的蒙特卡罗算法 总被引:1,自引:0,他引:1
集成工艺中控制图形发生器产生掩模图形的数据流文件的数据排列顺序优化,是一个其结点数可达数千个之多的大规模旅行商问题(从镜头架的位置,即每个矩形的矩心为结点),常规算法早已不适用。本文采用多阶段蒙特卡罗算法并加以改进,补充了“分层优化模式”,邻接结点的预合并和在各个阶段末提取共同子路径并删去相关结点等一系列逐步缩小问题规模的措施,形成了一个实用的优化算法。相应的软件已成功地应用于薄膜磁头的数据流文件的优化。 相似文献
989.
Yu. I. Mityaev Yu. I. Tokarev I. N. Sokolov É. É. Pakkh V. I. Abramov 《Atomic Energy》1992,73(1):558-563
Scientific-Research Construction Institute of Power Engineering. Russian Scientific Center Kurchatov Institute. Special Design Office of Industrial Organization Izhorskii Plant. All-Union Scientific-Research and Design Institute of Power Engineering Scientific-Industrial Organization. Translated from Atomnaya Énergiya, Vol. 73, No. 1, pp. 13–19, July, 1992. 相似文献
990.
多星观测调度是一个复杂的组合优化问题,且为NP难题.目前常用解决方法是采用智能搜索算法在搜索空间寻找近似最优解.针对上述问题,首先探讨了国内外成像侦察卫星调度算法的研究现状,然后阐述了传统微粒子群优化算法与免疫粒子群优化算法的特点,并对带有多个时间窗口约束的多星观测问题建立了数学模型.在此基础上,提出一种用于解决多星观测调度问题的免疫粒子群算法.实验结果表明,免疫算法收敛速度快,可以很好地逼近精确解,并具有较强的搜索能力. 相似文献