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131.
简述了专家系统的发展及在塑料加工中的应用特点,介绍了成功地开发PE、PP专家系统的方法、技术及实现功能,并提出了采用压缩库大大节约存贮空间的新途径。 相似文献
132.
133.
郭丽玲 《武汉理工大学学报(材料科学英文版)》2012,27(5):957-961
Layered organic-inorganic hybrids containing bilayer perovsikte (R-NH3)2(CH3NH3)Pb2I7 (where R=C12H25,C6H5C2H4) were synthesized by reactions in solution. The influences of the solvents and the reactant ratio on the structures of the products were investigated. The structures and the properties of the hybrids were characterized using X-ray diffraction (XRD) and ultraviolet and visible (UV) adsorption spectra. For comparing with the bilayer perovskite hybrids in structure and band gap magnitude, the hybrids containing monolayer perovskite (R-NH3)2PbI4 were also synthesized and characterized. The results demonstrate that the thickness of inorganic layer has obvious effect on the tunneling magnitude of the band gap but the organic part can be micro actuator of band gap. 相似文献
134.
An ecophysiological experiment was conducted to examine the biochemical effects of acidified seawater containing elevated concentration of CO(2) (C(CO2) 0.08, 0.20, 0.50 and 1.00%) on the copepod Centropages tenuiremis. AchE, ATPase, SOD, GPx, GST, GSH level and GSH/GSSG ratio of the copepod were analyzed. The results showed that elevated C(CO2) and the duration of culture time significantly influenced several biochemical indices in C. tenuiremis (ATPase, GPx, GST, GSH and SOD). Furthermore, the principal component analysis results indicated that 72.32% of the overall variance was explained by the first three principal components (GPx, SOD and GSH). Changes in GPx and GSH levels may play a significant role in the antioxidant defense of copepods against seawater acidification. The long-term response of copepods to seawater acidification and the synergistic effects of acidification with other environmental factors, such as temperature, salinity and trace metal need further investigation. 相似文献
135.
Yanhui Huang Xing Zhang Yangyu Fan Lijun Yin Lee Seversky James Allen Tao Lei Weijun Dong 《Image and vision computing》2012
3D face scans have been widely used for face modeling and analysis. Due to the fact that face scans provide variable point clouds across frames, they may not capture complete facial data or miss point-to-point correspondences across various facial scans, thus causing difficulties to use such data for analysis. This paper presents an efficient approach to representing facial shapes from face scans through the reconstruction of face models based on regional information and a generic model. A new approach for 3D feature detection and a hybrid approach using two vertex mapping algorithms, displacement mapping and point-to-surface mapping, and a regional blending algorithm are proposed to reconstruct the facial surface detail. The resulting models can represent individual facial shapes consistently and adaptively, establishing facial point correspondences across individual models. The accuracy of the generated models is evaluated quantitatively. The applicability of the models is validated through the application of 3D facial expression recognition using the static 3DFE and dynamic 4DFE databases. A comparison with the state of the art has also been reported. 相似文献
136.
The primary purpose of this paper is to propose a computer aided optimal design system to support a generalized oval–round pass design, which is widely used as both intermediate and final passes in the process of rod rolling. This system, which is based on a hybrid model and the genetic algorithm, is developed to improve the efficiency, to reduce the manufacturing errors, as well as to extend the useful life of rolls through uniform wear design. Generalized parametric equations are established for geometrical modeling, graphic plotting of oval–round passes, as well as calculation of the cross section area, contact area and the lengths of contact arcs along the cross section of round groove in the MATLAB programming environment. Moreover, these equations can also realize the parametric transformation between roll profile and mathematical models for the oval–round pass design and optimization. The genetic algorithm is employed for the optimal design of oval–round passes in this paper. The objective functions are formulated for minimization of power consumption in the rolling process, variances between ideal dimensions and design dimensions, as well as variances between the lengths of contact arcs. To reduce the complexity and computational burden of the system, some reliable empirical formulas for the calculations of contact area and contact arc length are applied. Finally, the proposed approach is applied to an oval–round pass design. Through simulation and comparison of results against experimental data acquired from literature, it is found that this system is reliable, effective and easier to use. 相似文献
137.
A compact genetic algorithm for the network coding based resource minimization problem 总被引:5,自引:3,他引:2
In network coding based data transmission, intermediate nodes in the network are allowed to perform mathematical operations
to recombine (code) data packets received from different incoming links. Such coding operations incur additional computational
overhead and consume public resources such as buffering and computational resource within the network. Therefore, the amount
of coding operations is expected to be minimized so that more public resources are left for other network applications. 相似文献
138.
网页自动化测试框架的设计与实现 总被引:1,自引:0,他引:1
随着软件开发项目的日益庞大,自动化测试技术的重要性日益突出。自动化测试技术的出现,大大提高了软件测试的效率和测试人员的积极性。但是自动化测试,尤其是网页自动化测试还存在不少的缺陷。分析了网页自动化测试中存在的难点,通过对同类软件的分析,提出了解决问题的指导思想和设计原则,并实现了一个网页自动化测试框架—NetAuto。NetAuto在开源项目Selenium的基础上,引入了对象库的概念,实现了测试脚本和测试数据的分离,并通过引入日志,报表,扩展接口等提高了测试的效率。通过实际的应用证明,NetAuto可以极大地提高测试工作的效率,尤其对于回归测试,可以完全替代人工。 相似文献
139.
ETL(Extraction-Transformation-Loading)是建立数据仓库的重要一环。通用应用ETL工具应能够适应不同领域不同需求的业务,无论是针对多样化异构的数据源,还是针对复杂变化的转换逻辑,都能够给予很好的支持。研究ETL工具的技术难点,提出一种通用ETL工具的设计框架,并对每个模块做了详细分析,在所承担项目中给出了具体实现。 相似文献
140.
反向选择模型是人工免疫系统中的经典模型,但存在训练代价高、覆盖率低的问题.危险理论模型是人工免疫系统中新引进的模型,在降低训练代价,提高覆盖率上具有优势.建立人工免疫危险理论模型必须解决的关键问题之一是:在保持人工免疫系统自适应特征的前提下,设计人工抗原提呈细胞.本文从抗原提呈细胞的生物学原理出发,设计了人工免疫系统中的人工抗原提呈细胞,给出单个人工抗原提呈细胞的结构、细胞上Toll样受体的结构,以及人工抗原提呈细胞群体的结构;设计了人工抗原提呈细胞群体的生命周期.初步的实验结果证明所设计的人工抗原提呈细胞具有自适应发现恶意软件的能力. 相似文献