深部调剖剂YG聚合物微球性能评价与应用

为考查深部调剖剂YG型聚合物微球在中原油田高温高矿化度油藏中的性能,通过透射电镜显微照相、吸水膨胀实验、岩心驱替实验和现场先导试验对其进行了性能评价与矿场应用。性能评价结果表明：该聚合物微球体积微小,可均匀分散在溶液中,与地层水表现出良好的配伍性;在95℃文留油田回注污水中,吸水膨胀倍数达40倍以上,具有较好的耐温抗盐和吸水膨胀性能;向中、低渗透率岩心注入微球体系过程中,呈现开始压力迅速上升、然后趋于稳定、压力略有下降的波动过程,具有较好的注入性;向中、高渗透率岩心注入微球体系过程中,随溶胀时间的延长,封堵率逐步增加,第10天达到最大,为17.14%。采用YG型微球在文留油田文10东块进行了深部调剖先导试验,取得了较好的开发效果。图6表4参5     

固相反应法制备Nd:YAG透明陶瓷

以Y(NO₃)₃和NH₃·H₂O为原料,并在Y(NO3)3溶液中添加少量(NH₄)₂SO₄,采用沉淀法制备出化学组成为Y₂(OH)₅(NO₃)·nH₂O的先驱沉淀物.先驱沉淀物在1100℃下煅烧4h,得到了平均粒径为60nm的氧化钇原料粉体.Y₂O₃粉体与Al₂O₃、Nd₂O₃超细粉球磨混合后,采用固相反应工艺,经1700℃真空烧结5h,制备出透明的Nd:YAG陶瓷,同时对Nd:YAG透明陶瓷的光学性能进行了研究.     

自然色彩在机电产品设计中的应用研究

产品色彩处理将使机电产品的形态、结构、审美等各个方面都提高一层次,有助于产品设计的渐趋完美。在机电产品的设计中色彩应具有主动的、引人入胜的感染力,能先于造型而影响人们情绪、心理的变化,这样才能在市场中提高自身的竞争能力。     

低分辨雷达目标分类的最小代价拒判算法

为解决低分辨雷达目标自动识别中,干扰目标、虚假目标的存在以及不同类别目标样本集混叠的问题,提出了一种基于最小代价的拒判K近邻识别算法.该算法根据雷达识别系统最小代价的原则,利用Fisher判别函数,确定拒判门限.设计了基于两类拒判域的K近邻识别算法,第一类拒判根据训练样本集特征值的波动范围,对干扰目标和虚假目标进行拒判;第二类拒判根据测试样本与最近邻、次近邻的距离差,实现混叠区域的目标样本拒判.算法先对测试样本进行拒判分析,再利用K近邻算法识别分类.实验结果表明,基于以上算法的低分辨雷达目标识别系统具有较好的鲁棒性和识别性能.     

一种新型的两级指纹分类方法

提出了一种利用隐马尔可夫模型(HMM)和支持向量机(SVM)的两级指纹分类新方法.该方法采用指纹编码(FingerCode)作为指纹的特征表述,在对分类器进行训练之后,首先用5个伪二维HMM对待分类指纹进行类别初选,确定最可能的两种指纹分类结果,再用相应的SVM分类器做最终判决.最后使用NIST-4数据库中的2000幅指纹和CQU-VERIDICOM数据库的1000幅指纹对该方法进行了实验,其分类的准确性为91%,连续性为93.7%,这证明了该方法的有效性.     

离散事件系统的混合型Petri网控制器

考虑由具有不可控变迁的受控Petri网建模的DES的控制器综合问题.提出了兼具DES的逻辑型和结构型二种控制器优点的混合型Petri网控制器:在系统状态的获取和跟踪上具有结构型控制器的优点,而在控制作用的实施上则具有逻辑型控制器的优点.全文通过实例说明了混合型Petri网控制器的设计方法.     

Query reformulation for dynamic information integration

The standard approach to integrating heterogeneous information sources is to build a global schema that relates all of the information in the different sources, and to pose queries directly against it. The problem is that schema integration is usually difficult, and as soon as any of the information sources change or a new source is added, the process may have to be repeated.The SIMS system uses an alternative approach. A domain model of the application domain is created, establishing a fixed vocabulary for describing data sets in the domain. Using this language, each available information source is described. Queries to SIMS against the collection of available information sources are posed using terms from the domain model, and reformulation operators are employed to dynamically select an appropriate set of information sources and to determine how to integrate the available information to satisfy a query. This approach results in a system that is more flexible than existing ones, more easily scalable, and able to respond dynamically to newly available or unexpectedly missing information sources.This paper describes the query reformulation process in SIMS and the operators used in it. We provide precise definitions of the reformulation operators and explain the rationale behind choosing the specific ones SIMS uses. We have demonstrated the feasibility and effectiveness of this approach by applying SIMS in the domains of transportation planning and medical trauma care.     

Discovering regularities from knowledge bases

Knowledge bases open new horizons for machine learning research. One challenge is to design learning programs to expand the knowledge base using the knowledge that is currently available. This article addresses the problem of discovering regularities in large knowledge bases that contain many assertions in different domains. the article begins with a definition of regularities and gives the motivation for such a definition. It then outlines a framework that attempts to integrate induction with knowledge. Although the implementation of the framework currently uses only a statistical method for confirming hypotheses, its application to a real knowledge base has shown some encouraging and interesting results. © 1992 John Wiley & Sons, Inc.     

结合红外传感器的室内输电线路老化监测系统

本文针对目前老旧房屋建成使用年份较早,线路老化十分严重,极易引发电气火灾的现状,结合可见光传感器、红外传感器和电磁感应装置,设计了一套室内输电线路热老化监测系统.电磁感应装置用于探测墙体内输电线缆的位置,红外传感器采用多点测温的方式监测墙体内导线或配电箱内导线的温度,可见光传感器用于监测点视频监控和对异常部位拍摄照片.如果发现数据异常等问题,本装置通过以太网通信模块将异常数据和照片传输至上位机.用户可以通过手机APP或PC客户端查看当前监测点温度、当前监测点实时视频监控和设置温度及电磁力阈值.一旦监测温度和电磁力数据超过阈值,系统将发出线路老化预警,用户可以收到手机APP和PC客户端的报警推送和异常部位的图片信息,及时处理老化线缆,避免因线路老化引发电气火灾.