单通道钻完井技术及其在我国海上油气田应用的可行性

介绍了单通道钻完井技术的基本概念、适用条件及主要特点,并简要介绍了UNOCAL公司在泰国湾应用该项技术取得的成果。UNOCAL公司在泰国湾进行单通钻完井作业时,对许多配套技术和管理理念进行了优化,使该项技术的整体效益更加突出。应用单通道钻完井技术可以大幅度降低钻完井费用。初步分析了单通道钻完井技术在我国海上油气田勘探开发中应用的可行性。     

提高碳三气相加氢催化剂加氢性能的措施

对燕山石化公司乙烯装置气相碳三加氢催化剂中毒失活的原因进行探讨，认为砷是Ｐｄ催化剂失活的最根本因素。采用低温空气氧化法对催化剂进行再生，效果优于传统再生方法，可延长催化剂运行周期。分析了影响催化剂加氢性能的诸因素，提出了提高碳三加氢催化剂加氢性能的措施，经济效益显著。     

涌泉灌技术在陈庄果园的应用

过临猗县闫家庄镇陈庄果园试点,对用涌泉灌、滴灌及微喷灌三种微灌技术进行比较,结果表明涌泉灌具有抗堵塞能力强、投资少、管理方便、使用寿命长等优点,应予优先推广     

Capacity of data collection in randomly-deployed wireless sensor networks

Data collection is one of the most important functions provided by wireless sensor networks. In this paper, we study theoretical limitations of data collection and data aggregation in terms of delay and capacity for a wireless sensor network where n sensors are randomly deployed. We consider different communication scenarios such as with single sink or multiple sinks, regularly-deployed or randomly-deployed sinks, with or without aggregation. For each scenario, we not only propose a data collection/aggregation method and analyze its performance in terms of delay and capacity, but also theoretically prove whether our method can achieve the optimal order (i.e., its performance is within a constant factor of the optimal). Particularly, with a single sink, the capacity of data collection is in order of \Uptheta(W)\Uptheta(W) where W is the fixed data-rate on individual links. With k regularly deployed sinks, the capacity of data collection is increased to \Uptheta(kW)\Uptheta(kW) when k=O(\fracnlogn)k=O\left({\frac{n}{\log n}}\right) or \Uptheta(\fracnlognW)\Uptheta\left({\frac{n}{\log n}}W\right) when k=\Upomega(\fracnlogn)k=\Upomega\left({\frac{n}{\log n}}\right). With k randomly deployed sinks, the capacity of data collection is between \Uptheta(\fracklogkW)\Uptheta\left({\frac{k}{\log k}}W\right) and \Uptheta(kW)\Uptheta(kW) when k=O(\fracnlogn)k=O\left({\frac{n}{\log n}}\right) or \Uptheta(\fracnlognW)\Uptheta\left({\frac{n}{\log n}}W\right) when k=w(\fracnlogn)k=\omega\left({\frac{n}{\log n}}\right). If each sensor can aggregate its receiving packets into a single packet to send, the capacity of data collection with a single sink is also increased to \Uptheta(\fracnlognW)\Uptheta\left({\frac{n}{\log n}}W\right).     

含有损耗双负介质的棱镜波导中古斯汉森位移特性研究

研究含有损耗的双负介质导波层的棱镜波导耦合系统中的古斯汉森(Goos-H?nchen,GH)位移增强效应。采用稳态相位理论得出了GH位移的表达式,并推导出获得较大GH位移的充分条件;通过仿真分析,研究了介电常数、包层和导波层的厚度对GH位移的影响,同时验证了增强GH位移的充分条件的有效性。结果表明,利用双负介质做棱镜波导系统的导波层可以有效克服材料自身带来的损耗,实现较大值的GH位移;同时,系统中的GH位移极大值对包层和导波层的厚度的微弱变化(1纳米)十分敏感,可用来制作高灵敏度的表面平整度探测器。     

车用开关磁阻电机的准线性数学建模与仿真

为研究车用开关磁阻电机系统(SRD),文章建立一种用线性数学模型模拟非线性数学模型的SRD的"准线性数学模型",并以此建立了SRD的MATLAB仿真模型。经过仿真分析可知"准线性数学模型"能从理论上比较准确、完整地描述SRM的电磁力关系及其动态性能,为后续SRD系统的研究奠定了理论基础。     

应用C++ Builder实现实时数据采集、显示的方法

集散控制系统中数据的实时采集和显示是较重要和较难实现的问题。文中针对一个自行设计的集散控制系统,介绍了在W Iindows操作系统下,利用可视化编程语言C Builder中的时间控件Ttimer完成定时作用,产生实时时间信号直接触发处于后台运行的程序,实现生产现场中数据的实时采集和数据动态显示。所用程序由可视化编程语言C Builder编写,给出了相应的程序。     

Improvement of cathode–electrolyte interfaces of tubular solid oxide fuel cells by fabricating dense YSZ electrolyte membranes with indented surfaces

To improve cathode–electrolyte interfaces of solid oxide fuel cells (SOFCs), dense YSZ electrolyte membranes with indented surfaces were fabricated on tubular NiO/YSZ anode supports by two comparable methods. Electrochemistry impedance spectroscopy (EIS) and current–voltage tests of the cells were carried out to characterize the cathode–electrolyte interfaces. Results showed that the electrode polarization resistances of the modified cells were reduced by 52% and 35% at 700 °C, and the maximum power densities of cells were remarkably increased, even by 146.6% and 117.8% at lower temperature (700 °C), respectively. The indented surfaces extended the active zone of cathode and enhanced interfacial adhesion, which led to the major improvement in the cell performance.