论网络环境下专业图书馆的创新服务

论述了专业图书馆的服务现状,分析了专业图书馆创新服务方面存在的问题,指出专业图书馆面对网络技术的挑战,必须在服务理念、服务内容、服务手段、服务模式、服务对象、服务队伍等方面进行创新,为读者提供更加优质的服务。     

鄂尔多斯盆地NL油田延9流动单元研究

从国内外流动单元研究现状出发,结合研究区实际的岩心、地质、测井和生产动态资料,根据流动带指标和岩性-物性划分法划分流动单元.研究中遵循单井、剖面到平面的思路,开展了流动单元特征参数优选、取心井流动单元分析、非取心井的流动单元划分工作.运用动态资料验证流动单元划分的合理性,进行了流动单元剖面、平面特征研究及流动单元生产能力分析.研究表明,所选用的渗透率、孔隙度和流动层带指标IFZ3个参数可满足本区流动单元划分要求,研究区延9储层流动单元可划分为Ⅰ、Ⅱ、Ⅲ、Ⅳ类.     

无人直升机局部H∞最优LPV 速度控制器设计

针对无人直升机的大范围鲁棒控制问题, 提出局部H_∞最优线性变参数(liner parameter varying, LPV)速度(local H_∞optimal LPV velocity, LHOV)控制方法。首先将无人直升机系统简化成含有干扰的LPV 系统，接着针对各个固定飞行模式独立设计H_∞静态输出反馈（H_∞static output feedback, HSOF）控制器，然后采用插补控制技术，针对每一种飞行模式下的线性系统设计一个只含有不可控部分和不可观部分的插补控制器，进而将所有模式下的控制器融合成一个LHOV控制器，从而既保证模式之间鲁棒转换，又使得系统进入任意一个模式后能达到H_∞性能最优。最后，仿真结果表明，采用此方法设计的控制器能够获得大范围良好的稳定性和鲁棒性。     

工程监理委托代理关系中激励约束 与参与约束的研究

基于委托－代理理论对工程监理委托－代理关系中的激励约束与参与约束进行若干拓展研究,与参 与约束（IR）相比,激励相容约束（IC）更为重要,一个机制不满足激励约束,那将是一个无效机制。业主想要 提高工程监理制度的运作效率,就必须通过相应的激励措施诱使工程师努力工作,使“道德风险”得以抑制, 为我国工程监理制度的健康发展提供了有益的启示。     

汽车自适应巡航系统中电子节气门的精确控制

在改装的捷达GTX轿车上研究ACC系统中电子节气门的控制策略.在控制方法中综合应用了多种PID算法,针对直流力矩电机机械特性对控制策略进行了优化,通过单片机的输出比较通道产生PWM以控制电机.通过实验台和实车试验,证明基于该控制策略开发电子节气门控制器的控制效果良好.     

复合絮凝剂应用于废水重金属去除效率的因素影响及其动力学研究

对PAC＋PAM复合絮凝剂应用于废水重金属去除效率的因素影响及其动力学进行了研究,通过考察PAC投加量、PAM投加量、PAC及PAM复合絮凝剂作用时最佳投加量、pH值、反应时间等因素对该实验室废水中铜的去除率影响,确定了反应的最佳条件,在此条件下铜的去除率可达96.7%。     

柴油机EGR温度的智能控制策略

利用改进的BP神经网络算法,建立了样本柴油机排气温度的神经网络模型,通过柴油机台架实验采集柴油机转速、负荷、油耗、排气温度等参数作为神经网络模型学习样本,使用实验数据对所建立模型进行训练,并对该神经网络模型进行了误差分析,结果表明,所建神经网络模型反映了实验样机的排气温度变化规律,在测试数据范围内,排气温度辨识误差小于...     

Evaluation of humic acid removal by a flat submerged membrane photoreactor

A flat submerged membrane combined with a TiO 2 /UV photocatalytic reactor (FSMPR) was employed in batch mode to remove humic acid (HA). HA removal efficiency was characterized by UV 254 absorbance, UV-vis spectra, dissolved organic carbon (DOC) concentration, specific UV absorbance (SUVA), and trihalomethane formation potential (THMFP). The FSMPR process was effective in removing more than 86% of DOC and nearly 100% of UV 254 absorbance, while the THMFPs of samples were reduced to < 19 μ g/L after 150 min of treatment. In addition, changes in transmembrane pressure (TMP) with and without UV were evaluated; TiO 2 /UV was effective at controlling membrane fouling by HA. Analysis of the molecular weight (MW) distributions and three-dimensional excitation-emission matrix (EEM) fluorescence spectra of HAs revealed that the effectiveness in membrane fouling control is a result of changes in HA molecular characteristics. The TiO 2 /UV photocatalytic reactor caused the degradation of high MW, hydrophobic humic-like molecules to low MW, hydrophilic protein-like molecules, although this fraction was not completely removed during 150 min of treatment and was less responsible for membrane fouling.     

Preparation of three-dimensionally ordered macroporous perovskite materials

In this paper,we use La0.8Sr0.2MnO3 and La0.7Ca0.2Sr0.1MnO3 as examples to demonstrate a preparation method for threedimensionally ordered macroporous(3DOM) perovskite thermochromic materials.Polystyrene spheres with an average diameter of 220 nm were self-assembled into a three-dimensionally ordered colloidal crystal template.A mixed metal nitrate solution prepared using La(NO3) 3·6H2O,Ca(NO3) 2·4H2O,Sr(NO3) 2,Mn(CH3COO) 2·4H2O and an ethanol precursor was used to fill the interstitial voids of the polystyrene colloidal crystal templates.3DOM La0.8Sr0.2MnO3 and La0.7Ca0.2Sr0.1MnO3 materials were then obtained after the sphere templates were removed via drying and calcination.The results show that the framework of the 3DOM materials can have different thicknesses and pore shrinkage rates by varying the filling times.In addition,the Curie temperatures of the 3DOM and bulk La0.8Sr0.2MnO3 materials can be varied by altering the preparation method.     

非自治吊桥方程的一致吸引子

作者讨论了非自治吊桥面方程的长时间动力学行为.通过应用一些新的结果和能量估计技巧,获得了能量的一致衰退估计.当外力项f满足条件（C*）（而非平移紧）时,作者证明了一致吸引子在H20（Ω）×L2(Ω)上的存在性,此结果推广和改进了一些已有结果.