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991.
Tan Guang-ming Wang Zhen-zhong Wuhan University of Hydraulic Electric Engineering Wuhan P.R.China 《水动力学研究与进展(B辑)》1992,(1)
It is mentioned in this paper that the adjustment of flow structure occurs when themain-flow swings.The changes of turbulence structure and flow energy loss in the indoor rivermodel are measured.The experimental data are presented for the first time for the further studyof complicated river flow structure. 相似文献
992.
Postoperative feeding with a special-purpose foodstuff Ovolact proved superior to tube feeding in patients on after treatment following surgical correction of congenital jaw defects. This was evident from assessment of anthropometric and protein metabolism parameters. Nitrogen metabolism underwent positive changes reflecting the product value for maintenance of protein status of the above patients. Therefore, Ovolact can make more effective postoperative rehabilitation in jaw reconstruction. 相似文献
993.
994.
The 320C30 is a fast processor with a large memory space and floating-point-arithmetic capabilities. The authors describe the 320C30 architecture in detail, discussing both the internal organization of the device and the external interfaces. They also explain the pipeline structure, addressing software-related issues and constructs, and examine the development tools and support. Finally, they present examples of applications. Some of the major features of the 320C30 are: a 60-ns cycle time that results in execution of over 16 million instructions per second (MIPS) and over 33 million floating-point operations per second (Mflops); 32-bit data buses and 24-bit address buses for a 16M-word overall memory space; dual-access, 4 K×32-bit on-chip ROM and 2 K×32-bit on-chip RAM; a 64×32-bit program cache; a 32-bit integer/40-bit floating-point multiplier and ALU; eight extended-precision registers, eight auxiliary registers, and 23 control and status registers; generally single-cycle instructions; integer, floating-point, and logical operation; two- and three-operand instructions; an on-chip DMA controller; and fabrication in 1-μm CMOS technology and packaging in a 180-pin package. These facilitate FIR (finite impulse response) and IIR (infinite impulse response) filtering, telecommunications and speech applications, and graphics and image processing applications 相似文献
995.
Dental amalgams are based on a broad spectrum of materials differing in their chemical composition, metallurgical treatment, and in the way the initial alloys powders are prepared. In addition to their chemical composition, amalgams based on various powders differ in both their microstructure and the amount of mercury needed for preparation. All these facts may affect electrochemical processes occurring during their interaction with oral fluids, and also mercury release. While verifying the effect of the technology used for the preparation of the high‐copper ternary alloy powder on the properties of resulting amalgams, this study aimed at the mechanism of their interaction with a model saliva solution as well as mercury release was included. Measurements were done in a model saliva solution using standard electrochemical methods and exposition measurements. The interaction of individual types of amalgams with artificial saliva did not reveal any significant differences. The free corrosion potential of all these amalgams in an aerated solution settled in the range of values in which tin oxidation, resulting in a layer of insoluble corrosion producsts, turned out to be the dominant anodic process. The rate of mercury release was the lowest for amalgams based on a gas‐atomized alloy. The highest rate of mercury release, and also its dependence on time, was exhibited by lathe‐cut powder based amalgam. In addition to different volume fraction of the Ag‐Hg phase and the level of its tin alloying, this different behaviour may be explained by differences in the rate at which a layer of tin corrosion products acting as a barrier to mercury release is formed. 相似文献
996.
As an alternative to a symbolic interpretation of transitivity in the discriminative performance of pigeons, a modified reinforcement theory (value transfer theory) was proposed by L. von Fersen et al (see record 1991-29523-001). Its novel assumption was that the value of the negative member of a pair of stimuli with which an animal is trained is enhanced by the value of the positive member of the pair. In this article, that assumption is shown to be unnecessary. All of the transitivity data for pigeons can be simulated with a simple conditioning model developed for honeybees that retains the conventional independence assumption. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
V. M. Boyarskii L. P. Mikhailov I. S. Sheinin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(10):623-627
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 11–13, October, 1992. 相似文献
998.
999.
N. K. Savant P. S. Ongkingco I. V. Zarate F. M. Torrizo P. J. Stangel 《Nutrient Cycling in Agroecosystems》1991,28(3):323-331
A plunger-type, completely hand-operated applicator prototype, made of polyvinyl chloride (PVC), for deep placement of urea briquettes (UB), i.e., pillow-shaped urea supergranules with edges, in line transplanted rice has been developed for use by small-scale rice farmers. The field evaluation of the applicator was conducted in the Philippines during the 1989 dry season. The applicator consistently placed UB at proper depth (7 to 8 cm), which resulted in low concentrations of urea N (<7 ppm) in about 4 cm of floodwater 1 day after placement. These findings indicated that the prototype worked properly. Average work output of the applicator was 0.20 ha workday–1 and may increase with practice. The yields of irrigated transplanted rice in the field trials show that agronomic efficiencies of hand-placed UB and applicator-placed UB were equal and were superior to those of split-applied prilled urea. 相似文献
1000.
Conclusions The phenomenological model (1) makes it possible to use a single approach to interpreting the phenomena taking place. The theoretical predictions are in agreement with the experimental data so that it can be concluded that the theory of cooperative processes can be used efficiently in the physical mechanics of materials. It is extremely important to take into account the dynamic unity of all collective effects caused both by the nonequilibrium state of the system and by its interaction.Presented at the 9th Conference on Metal Fatigue, Moscow, December 16–18, 1986.Translated from Fiziko-Khimicheskaya Mekhanika Materialov, No. 1, pp. 37–42, January–February, 1988. 相似文献