车载液压发电机行车发电转速补偿控制

研究了变转速输入和负载扰动下马达稳速输出控制方法。基于欧洲NEDC循环路况构建车辆行驶仿真模型、泵控马达数学模型以及负载数学模型,提出车载液压发电机泵控马达稳速输出控制策略,对系统进行仿真研究。结果表明在变转速输入和负载扰动下,加入转速补偿控制能够极大提高控制精度和鲁棒性。     

Applying reticular synthesis to the design of Cu-based MOFs with mechanically interlocked linkers

The concept of“robust dynamics”describes the incorporation of mechanically interlocked molecules(MIMs)into metal-organic framework(MOF)materials such that large amplitude motions(e.g.,rotation or translation of a macrocycle)can occur inside the free volume pore of the MOF.To aid in the preparation of such materials,reticular synthesis was used herein to design rigid molecular building blocks with predetermined ordered structures starting from the well-known MOF NOTT-101.New linkers were synthesized that have a T-shape,based on a triphenylene tetra-carboxylate strut,and their incorporation into Cu(II)-based MOFs was investigated.The single-crystal structures of three new MOFs,UWCM-12(fof),β-UWCM-13(loz),UWCM-14(lil),with naked T-shaped linkers were determined;β-UWCM-13 is the first reported example of the loz topology.A fourth MOF,UWDM-14(lil)is analogous to UWCM-14(lil)but contains a[2]rotaxane linker.Variable-temperature,²H solid-state NMR was used to probe the dynamics of a 24-membered macrocycle threaded onto the MOF skeleton.     

Holding Pattern

Holding Pattern是Interboro事务所为MoMA PS12011年青年建筑师计划提交的获胜方案,它是为MoMA PS1在2011年6月19日开放的露天庭院而做的一个项目。为了设计Holding Pattern,Interboro向博物馆的邻居们调研了以下问题:有没有什么你们需要的东西我们可以设计,然后将之布置在这个庭院中展览并使用一个夏天,到秋季撤展的时候再捐赠给你们?Interboro询问了出租车公司、图书馆、高中、老年中心和日托中心、社区公园、邮局和很多其他位于纽约长岛的机构,     

Raster to Vector Conversion for Engineering Drawings： Survey and Prospect

1 Introduction Raster to Vector Conversion (RVC) for Engineering Drawings(ED), also known as vectorization, is a procedure to find the vector form of graphic primitives – straight line, circle and arc segments – from the raster engineering drawing. It is an automated process of analyzing and recognizing graphic primitives in the raster engineering drawing, converting them into vector form. A lot of instances need to accomplish the raster to vector recognition and conversion, for example,…     

Research on the measurement of the price change of telecom services in China

1 Introduction The telecom service price (TSP) is the focus of benefit of distribution between telecom enterprises and customers. With the opening of the telecom service market and the increasing competition, the changes in the TSP became more frequent, e…     

基于Agent的电器设备智能测控网络的研究

基于LonWonks的测控网络结构,采用面向Agent的设计思想,结合神经网络和模糊控制的技术特点,提出了一种实现网络电器智能控制的Agent模型。     

Effects of Ta addition on the microstructure and mechanical properties of Ti_(40)Zr_(25)Ni_8Cu_9Be_(18) amorphous alloy

The effects of Ta addition on the microstructure and mechanical properties of Ti40Zr25Ni8Cu9Be18 bulk amorphous alloy were investigated by using X-ray diffraction (XRD), transmission electron microscopy (TEM), scan electron microscopy (SEM) and compressive testing. As a result, the addition of Ta (0-8at%) prompted the successive precipitation of quasicrystalline phase, CuTi2 phase and bcc β-Ti solid solution. Additionally, the addition of less Ta content (3at%-5at%) led to the formation of amorphous ma- trix/nanoquasicrystal/CuTi2 complex phase structure; and nanoquasicrystals, as reinforcement precipitates, improved the fracture strength of Ti-Zr-Ni-Cu-Be-Ta alloys, which led to the high compressive fracture strength 1856 MPa of Ta5 alloy. With increasing Ta content (5at%-8at%), although the ductile dendritic β-Ti solid solution was precipitated, the strength and plasticity decreased to a great extent resulting from the growth of quasicrystalline phase and CuTi2 phase.     

Ultralight X-type lattice sandwich structure (I): Concept,fabrication and experimental characterization

A new type of ultra-lightweight metallic lattice structure (named as the X-type structure) is reported. This periodic structure was formed by two groups of staggered struts in the traditional pyramid structure, and fabricated by folding expanded metal sheet along rows of offset nodes and then brazing the folded structure (as the core) with top and bottom facesheets to form sandwich panels. The out-of-plane compressive and shear properties of the X-type lattice sandwich structure were investigated experimentally and compared to those of the sandwich having a pyramidal truss core. It is found that the formation of the 2-dimensional staggered nodes can effectively make the X-type structure more resistant to inelastic and plastic buckling under both compression and shear loading than the pyramidal lattice truss. Obtained results show that the compressive and shear peak strengths of the X-type lattice structure are about 30% higher than those of the pyramidal lattice truss having the same relative density. Supported by the National Basic Research Program of China (“973” Project) (Grant No. 2006CB601202), the National Natural Science Foundation of China (Grant Nos. 10632060,10825210), the National “111” Project of China (Grant No. B06024) and the National High-Tech Research and Development Program of China (“863” Project) (Grant No. 2006AA03Z519)     

螺内酯治疗慢性充血性心力衰竭的临床观察

目的观察小剂量醛固酮拮抗剂螺内酯治疗慢性充血性心力衰竭(CHF)的有效性和安全性。方法选择各种心血管疾病所致的CHF患者64例,随机分为治疗组(A组32例)和对照组(B组32例),二组均给予常规综合疗法抗CHF治疗,A组联用螺内酯(20mg/d)治疗前和治疗后6个月分别进行心功能(NYHA)分组评估、超声心动图及生化检查,同时观察6min步行试验,并进行对照。结果治疗6个月A、B组心功能分级LVEF、SV、CI)和6min步行距离较治疗前均显著改善(P<0.05)与B组比较,A组改善最显著(P<0.05)。未发现严重高血钾及其他严重不良反应。结论应用螺内脂治疗CHF疗效肯定,安全性高。     

南津渡水电站机组过频保护动作引起停机的技术改进

文章针对南津渡水电站机组过频保护动作引起停机的问题进行分析，并主要从提高机组运行的稳定性方面提出一些解决问题的技术措施和改进方案。