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91.
针对钻井井控作业特点及传统钻井井控仿真系统的不足之处,提出利用多智能体(Agent)技术,建立一种新型的基于Agent的智能化分布式井控仿真模型。利用Agent的自主性、协作性和反应性,使井控设备的操作在任意状况下都能够及时准确地反映各种井控规律及井控现象。对钻井井控仿真多Agent系统模型、各Agent的内部结构、Agent的知识表示方法及Agent间通信方式进行了详细阐述。给出了基于Agent的正常钻井井控仿真训练实例,较好地解决了传统井控仿真系统中灵活性和并发性较差的问题,增强了井控仿真系统的综合训练能力。 相似文献
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Blends of polyamide and high‐density polyethylene show adequate properties for a large range of applications: they are used for the production of filaments, containers, and molding resins. The effect of the addition of 2 wt % of a compatibilizer, maleic anhydride grafted polyethylene, to the blend was studied and compared to the use of postconsumer polyethylene. The samples were extruded with single‐ and twin‐screw extruders with 25, 50, or 75 wt % f polyethylene, and the test specimens, molded by injection, were characterized by stress–strain tests, thermal properties, and morphologies. Processing the blends with postconsumer polyethylene in both extruders improved the mechanical properties in comparison to the blends processed with high‐density polyethylene and the compatibilizer. The morphologies of these blends showed that there was a decrease in the domain size of the disperse phase with the use of the compatibilizer or postconsumer polyethylene. The results indicate that for this blend, postconsumer polyethylene substituted, with advantages, for the necessity of a compatibilizer and the use of the high‐density polyethylene. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008. 相似文献
94.
脱硫副反应及副盐回收技术研究 总被引:1,自引:0,他引:1
通过例举生成Na2S2O3、Na2SO4、NaCNS的副反应,阐述了碱性水溶液脱除H2S多过程中发生的脱硫副反应,分析了温度、pH值和运转时间与生成物Na2S3O3的关系;简述了副产物对脱硫的影响;论述了回收Na2S3O3、NaCNS、(NH4)2S2O3、NH4CNS以及采用硫酸法和盐酸法精制NaCNS的基本原理和工艺流程;介绍了Na2S2O3等副盐的产品质量标准. 相似文献
95.
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97.
Hybrid finite-element method for discretising cylindrically symmetric parts in electrotechnical models 总被引:1,自引:0,他引:1
In many technical devices such as transformers and electrical machines, large differences in geometric dimensions are observed. As a consequence, the generation of a 3D computational grid for the whole device leads to unacceptably large numbers of elements or can even fail. In addition to the commonly applied cartesian or cylindrical symmetries of the overall geometry, the model can be subdivided into parts featuring translational or cylindrical symmetries. Such parts are discretised separately, accounting for the local symmetry, and are then combined with the surrounding 3D model. Excitations and boundary conditions of the submodels are not necessarily symmetric but are expected to be smooth in the direction of the symmetry. Then, the field distribution at the interface is well approximated by a set of spectral elements along the dimension of symmetry. Coupling between the model parts is carried out by means of Lagrange multipliers. A single-phase transformer with thin insulation sheets is taken as an example to illustrate the proposed hybrid discretisation. The cross-section of the cylindrically symmetric part containing thin sheets, is represented by a fine 2D finite-element mesh so that all the geometrical details can be resolved, and the rest of the structure is discretised by a 3D mesh. Nevertheless, a fully 3D field distribution is calculated in all model parts. Only a small number of harmonic functions is needed to account for the azimuthal field variation at the cylindrical interface. Hence, the number of unknowns in the numerical model is reduced significantly, while a high level of accuracy is maintained 相似文献
98.
GSM技术在配电网故障自动隔离及恢复系统的应用 总被引:1,自引:0,他引:1
为了使配电网故障的隔离和恢复的通讯更加可靠、迅速、经济,设计了一种基于GSM通讯技术,借助移动通讯系统短信业务和数据业务,实现配电网故障的自动隔离与恢复的系统。该系统通过MCU采集数据,判断故障位置与故障类型,经GSM通讯模块上传主站,主站统筹全局,实现故障段的切除,非故障区的供电。阐述了系统的工作原理、硬件结构、通讯协议和软件流程。现场的实际运行情况证明数据上报通讯准确率为100%,多次模拟线路故障,根据故障点的不同,一般在2~3min内系统都能可靠的隔离故障,恢复系统。 相似文献
99.
100.
WANG Ju-hui 《通讯和计算机》2008,5(11):48-52
This paper comes true a system of facial detection and location. Firstly, it realizes the facial detection of candidate region used skin color for the given image, and considers the influence of similar skin. Secondly, it realizes the location for eye region used the gray characteristic of eye and correction of central measurement, and makes further selection for facial candidate region. The end, it normalizes the facial image and makes it as front standard image, so realizes the facial characteristic location. 相似文献