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81.
根据相似性原理,选择不同的相似材料模拟双侧挤压作用下含盐不均匀基底变形对盖层构造的影响。实验表明:(1)双侧挤压背景下,受硬泡沫和凡士林代表的不同性质的基底的影响,上覆细沙盖层中形成的构造样式不同;(2)尽管模型的基底结构左右两侧基本对称,但上覆盖层的变形样式并不完全对称;(3)变形后期,盐脊顶部上覆沙层出现明显的塌陷构造;(4)实验最终结果显示的整个背冲构造的形成是由两个分割开的次级构造逐步合并而成的。 相似文献
82.
83.
A thermodynamic modeling of GaN was carried out to describe the thermodynamic behavior of native defects, dopants, and carriers
(free electrons and holes) in GaN semiconductors. The compound energy model (CEM) was used. An unintentionally doped GaN was
taken as an example. Oxygen was introduced into the model as the unintentionally doped impurity, according to the practical
experimental phenomena. The energies of component compounds in the model were defined based on the results of the ab initio
calculations and adjusted to fit experimental data. The thermodynamic properties of the defects and the oxygen doped were
calculated to show the facility of the model. 相似文献
84.
Inaki Arrazola Agn s Plainfoss Henri Prade Claudette Testemale 《Information Systems》1989,14(6):487-492
This paper presents different approaches which enable a data base management system to obtain a plausible fuzzy estimate for an attribute value of an item for which the information is not explicitly stored in the data base. This can be made either by a kind of analogical reasoning from information about particular items or by means of expert rules which specify the (fuzzy) sets of possible values of the attribute under consideration, for various classes of items. Another kind of expert rules enables the system to compute an estimate from the attribute value of another item provided that, in other respects, this latter item sufficiently resembles the item, the value of which we are interested in; then these expert rules are used either for controlling the analogical reasoning process or for enlarging the scope of application of the first kind of expert rules. The different approaches are discussed in the framework of possibility theory. 相似文献
85.
区域防空联合预警体系探测效能分析 总被引:6,自引:0,他引:6
将联合预警体系划分为不同的子系统,按照系统集成的方法,分析和计算了区域防空条件下联合预警装备体系的探测效能;结合防空兵部队联合预警系统发展的需求,以定量的形式为联合预警体系的构建提供决策依据。 相似文献
86.
The physical gestures that operate music instruments are responsible for the qualities of the sound being produced in a performance.
Gestural information is thereby crucial for a model of music performance, paired with a model of sound synthesis where this
information is applied. The highly constrained nature of performers gestures makes this task suitable to be modeled via a
constraint-based approach, coupled with a strategy aimed at maximizing the gestural comfort of performers. We illustrate the
problem representation, the search strategy and a validation of the model against human performance. 相似文献
87.
The requirements on an object-oriented DBMS for management of information in a large, complex enterprise are presented. These requirements aid in the achievement of an environment characterized by data sharing, open architectures, application and data portability, and assurance of data integrity. They were defined from the point of view of a user of the DBMS; therefore they describe the expected functionality of the DBMS and do not specify the method of implementation to achieve this functionality. They encompass requirements on the data model, query and data manipulation languages, the system architecure, interfaces to the system, change management, and transaction management. 相似文献
88.
化工软测量技术研究进展 总被引:2,自引:0,他引:2
详细说明了软测量技术的含义以及软测量系统的组成。在此基础上,介绍了软测量技术中基于机理分析建模、应用状态观测器建模、应用统计分析建模、神经元网络、模糊技术、以及支持向量机的智能建模等软测量建模理论方法和最新研究成果,之后介绍了小波分析、推断控制算法在软测量数据处理中的应用,最后介绍了基于虚拟仪器开发平台的软测量系统实现技术。 相似文献
89.
90.
Omar Snchez Estrella Asp María C Martí Marlene Roeckel 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(11):1261-1267
Most of the kinetic studies on nitrification have been performed in diluted salts medium. In this work, the ammonia oxidation rate (AOR) was determined by respirometry at different ammonia (0.01 and 33.5 mg N‐NH3 L?1), nitrite (0–450 mg N‐NO2? L?1) and nitrate (0 and 275 mg N‐NO3? L?1) concentrations in a saline medium at 30 °C and pH 7.5. Sodium azide was used to uncouple the ammonia and nitrite oxidation, so as to measure independently the AOR. It was determined that ammonia causes substrate inhibition and that nitrite and nitrate exhibit product inhibition upon the AOR. The effects of ammonia, nitrite and nitrate were represented by the Andrews equation (maximal ammonia oxidation rate, rAOMAX, = 43.2 [mg N‐NH3 (g VSSAO h)?1]; half saturation constant, KSAO, = 0.11 mg N‐NH3 L?1; inhibition constant KIAO, = 7.65 mg N‐NH3 L?1), by the non‐competitive inhibition model (inhibition constant, KINI, = 176 mg N‐NO2? L?1) and by the partially competitive inhibition model (inhibition constant, KINA, = 3.3 mg N‐NO3? L?1; α factor = 0.24), respectively. The rAOMAX value is smaller, and the KSAO value larger, than the values reported in diluted salts medium; the KIAO value is comparable to those reported. Process simulations with the kinetic model in batch nitrifying reactors showed that the inhibitory effects of nitrite and nitrate are significant for initial ammonia concentrations larger than 100 mg N‐NH4+ L?1. Copyright © 2005 Society of Chemical Industry 相似文献