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1.
Dielectric measurements and X-ray diffraction studies were made in the system BaTiO3-BaHfO3 for polycrystalline specimens containing from 0 to 30 mole % BaHfO3. The maximum in the dielectric constant for each composition in creased as the BaHfO3 concentration was in creased to 16 mole % and then decreased with further BaHfO3 additions. Room-temperature lattice constants and hysteresis loops were meas ured for all compositions. A partial solid-state phase diagram is suggested for the solid solution area of the system. The phase diagram and the dielectric behavior of the system up to 16 mole % BaHfO3 are explained on the basis of Devonshire's thermodynamic theory. The ferroelectric-paraelectric transition in the composition containing 16 mole % BaHfO3 was essentially of second order and occurred between a ferroelectric rhombohedral phase and a paraelectric cubic phase.  相似文献   
2.
In this paper we present a review of the development of the discrete maximum principle. In the presentation, the emphasis is on a geometrical interpretation. The crucial assumptions in the theory developed are pointed out, and the attempts to overcome the limitation in the resulting theorems ore exposed. Following the review, we present a new approach to optimization of the multi-stage optimization problems called the ’ upper boundary approach ’. The classical methods of solving this problem are shown to fit smoothly into the new approach. Moreover, using this approach a number of new results have been developed, among these a new generalized version of the discrete maximum principle. The new version does not require the assumption of directional convexity.  相似文献   
3.
A great number of organism development processes can be accounted for by the elementary mechanisms of cell partition and cell transformation. In the present article an analytical method is presented which emphasizes the link that exists between the generating word of an organism (in the language consisting of the possible cell transformations) and the successive structures of the developmental process. The viewpoints of analysis (types of structures generated by a given type of word) and of synthesis (type of word generating a given type of structure) are considered. As an illustration of the method models of development are constructed which have already been proposed empirically to account for two types of plant development.  相似文献   
4.
The model for developmental systems used by the present authors in the foregoing eight parts is generalized and compared to biological facts concerning DNA.  相似文献   
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The purpose of this paper is to investigate the problem of finding inputs which generate zero outputs in linear systems whose state equation contains the derivative of the input. The method developed makes use of the simplest matrix generalized inverse, the {1}-inverse.  相似文献   
8.
Abstract

Manufacturing automation has progressed through various stages from simple data transfer to the intelligence-intensive systems. The future of CIM relies heavily on intelligence-intensive systems because manufacturing is no longer confined to one local site and manufacturing systems have become complex because of their global nature. In this article, the authors study the future manufacturing environment as a collaborative effort. The essential characteristics-the requirements for integration from a process and communication perspective-are identified as are steps in the process requiring further study. Finally, Intelligent-Computer Integrated Manufacturing (I-CIM) scenarios are presented for specific problems.  相似文献   
9.
Liquid-liquid equilibrium data for two ternary systems were obtained. The experimental data were measured for cyclohexane-toluene-sulfolane at 17, 25 and 50°C, and for hexane-toluene-sulfolane at 18 and 25°C. The NTRL and UNIQUAC models were used to correlate the experimental results and to calculate the phase compositions of the ternary systems. The agreement between the experimental results and the fitted values was equally good with both of the models.  相似文献   
10.
Recent progress in biology and microscopy has made it possible to acquire multidimensional data on rapid cellular activities. Unfortunately, the data analysis needed to describe the observed biological process still remains a major bottleneck. We here present a novel method of studying membrane trafficking by monitoring vesicular structures moving along a three-dimensional cytoskeleton network. It allows the dynamics of such structures to be qualitatively and quantitatively investigated. Our tracking method uses kymogram analysis to extract the consistent part of the temporal information and to allow the meaningful representation of vesicle dynamics. A fully automatic extension of this method, together with a statistical tool for dynamic comparisons, allows the precise analysis and comparison of overall speed distributions and directions. It can handle typical complex situations, such as a dense set of vesicles moving at various velocities, fusing and dissociating with each other or with other cell compartments. The overall approach has been characterized and validated on synthetic data. We chose the Rab6A protein, a GTPase involved in the regulation of intracellular membrane trafficking, as a molecular model. The application of our method to GFP-Rab6A stable cells acquired using fast four-dimensional deconvolution video-microscopy gives considerable cellular dynamic information unreachable using other techniques.  相似文献   
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