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941.
Protsko L.B. Sorenson P.G. Tremblay J.P. Schaefer D.A. 《IEEE transactions on pattern analysis and machine intelligence》1991,17(1):10-21
The authors formulate the criteria for drawing dataflow diagrams and describe the placement and routing algorithms used in a system called MONDRIAN. A generalized approach to the question of software diagrams is proposed based on the authors' experience with MONDRIAN and a metasystem approach to the creation of CASE (computer-aided software engineering) environments. A formal approach to the definition of software objects and their graphical representation is given. The use of location constraints as a basis for generalized layout algorithms is discussed 相似文献
942.
943.
S. O. Slesarevskii A. M. Belavskii M. N. Korotenko V. S. Lyubarskii V. P. Pavlenko V. A. Snigerev A. V. Tkachenko 《Atomic Energy》1989,67(5):853-855
Translated from Atomnaya Énergiya, Vol. 67, No. 5, pp. 358–359, November, 1989. 相似文献
944.
945.
A new learning model for real-time, grey-level image segmentation is presented. The model gives excellent results for images with different shapes. 相似文献
946.
WC-(Fe, Ni, C) cemented carbides can be successfully transformation-toughened by careful control of binder composition and
taking into consideration the effect of thermal residual stress on the transformation characteristics of the binder. An additional
degree of control on the metastability of the binder phase can be achievedvia thermomechanical treatments. These treatments consist of transforming an austenitic binder to martensite by cooling in liquid
nitrogen followed by a suitable high temperature heat treatment to reaustenitize it. Thein situ deformation of the binder caused by the large shape and volume changes that accompany its transformation to martensite thus
provides the mechanical component of the thermomechanical treatment. Subsequent heat treatments not only reaustenitize the
binder but also modify its susceptibility to undergo stress-induced transformation. It is shown that the hardness/fracture
toughness behavior of WC-(Fe, Ni, C) cemented carbides can be significantly improved by the application of such treatments.
A qualitative explanation for the enhancements in fracture toughness provided by thermomechanical treatments is offered based
on a careful examination of the changes in phase constitution of the binder that occur during these treatments.
Formerly Manager, Research-Development, Reed Tool Company, Houston, TX. 相似文献
947.
V. V. Tcherdyntsev S. D. Kaloshkin A. I. Salimon E. A. Leonova I. A. Tomilin J. Eckert F. Schurack V. D. Rogozin S. P. Pisarev Yu. P. Trykov 《Materials and Manufacturing Processes》2002,17(6):825-841
Al-Cu-Fe alloys were prepared from elemental powders in a high-energy planetary ball mill. A sequence of solid state reactions resulting in quasicrystal (QC) phase formation takes place during heating of the as-milled powder. These reactions were studied by both differential scanning calorimetry and x-ray diffraction methods. Mechanically alloyed powders were consolidated by cold and hot pressing, as well as by explosive compaction. After annealing at sufficiently high temperatures, the consolidated samples are single-phase QC, except the ones consolidated by explosion. The high reactivity of the as-milled alloys causes the appearance of high porosity of the consolidated samples after the annealing. 相似文献
948.
The basic principles of a new surface acoustic wave (SAW) gas sensor are described. Being essentially a sensor of the sorption type, the proposed device possesses certain features of the thermometric SAW sensors and is not only sensitive to the vapors of volatile substances, but capable of detecting gases by their thermal properties as well. In contrast to the known thermometric SAW sensors, the proposed sensor is characterized by high temperature stability and fast response. A variant of the sensor based on a LiNbO3 SAW delay line is described and some results of the test for detecting propane-butane mixtures are presented. 相似文献
949.
Mathematical simulation is used to study the dependence of the parameters of an electronuclear system with uranium–plutonium mixed fuel on the amount of plutonium and 240Pu admixture in the fuel. As an example, a 10–20 kW(t) experimental system built at Dubna on the basis of a synchrocyclotron with 660 MeV protons is examined. A 2% admixture of 240Pu decreases the neutron multiplication factor from 0.95 to 0.9 and decreases the neutron yield and heat released by almost a factor of 2. This decrease can be compensated by increasing the plutonium content in the mixed fuel from 25 to 27%. 相似文献
950.
An annual report on meetings of the scientific research seminar on computer algebra is presented. 相似文献