Analogue implementation of a neural network controller for UPSinverter applications

An analogue neural-network controller for UPS inverter applications is presented. The proposed neural-network controller is trained off-line using patterns obtained from a simulated controller, which had an idealized load-current-reference. Simulation results show that the proposed neural-network controller can achieve low total harmonic distortion under nonlinear loading condition and good dynamic responses under transient loading condition. To verify the performance of the proposed NN controller, a hardware inverter with an analogue neural network (NN) controller (using mainly operational amplifiers and resistors) is built. Additionally, for comparison purposes, a PI controller with optimized parameters is built. Experimental results confirm the simulation results and show the superior performance of the NN controller especially under rectifier-type loading condition. Implementing the analogue neural-network controller using programmable integrated circuits is also discussed     

硫对注入YSZ单晶的金属铂在退火过程中结晶的影响

秀卢瑟福背散射－沟道技术（ＲＢＳ－Ｃ）和Ｘ射线衍射技术（ＸＲＤ）研究了Ｐｔ和注入ＹＳＺ（Ｙ２Ｏ３稳定的ＺｒＯ２）后产生的损伤和退火过程中损伤的恢复及注入Ｐｔ的晶化，ＲＢＳ－Ｃ分析表明ＹＳＺ室温下的存在较强自退火效应，ＸＲＤ分析结果示出硫以铂的晶化产生很大影响。     

Synthesis and characterization of block copolymers from D,L-lactide and poly(tetramethylene ether glycol)

The copolymer from D ,L -lactide and poly(tetramethyene ether glycol) (PTMG) was prepared in bulk with an isotributyl aluminum–water–phosphoric acid complex catalyst as the initiator and characterized by H-NMR, GPC, and DSC. The effects of the temperature and the amount of PTMG on the polymerization rate and the molecular weight of copolymers were studied. The behavior of the degradation and delivery rate of Levonorgestrel microspheres in vitro was observed. The results show that the degradation and the delivery rate can be controlled by adjusting the molar rate of hydrophilic and hydrophobic segments of the copolymer © 1995 John Wiley & Sons, Inc.     

两种具有电双稳态的全有机络合物

首次发现两种在室温下即具有电双稳态的全有机（有机-有机）络合物，分别称为MCA＋TCNQ和BBDN＋TCNQ。它们可在真空中制备成薄膜，在数伏电压的作用下，从高电阻至低电阻的跃迁时间小于100ns，因此可作为一次写入的存储器材料。根据我国目前最小刻线宽度的水平，可望在1．6cm2的SiO2平面上做出64Mb的存储器。     

Stochastic TCP friendliness: Expanding the design space of TCP-friendly traffic control protocols

While the current definition of TCP friendliness has enabled a wide variety of traffic control protocols other than TCP, it still considerably restricts the design space of TCP-friendly traffic control protocols. For example, some multimedia streaming applications prefer a smooth sending rate on a time scale of tens of seconds, however, a UDP flow maintaining such a long smoothness time scale is naturally not TCP friendly by the current definition. In this paper, we propose an innovative method to relatively compare the degrees of TCP friendliness of different traffic control protocols, and use it to define a new class of TCP friendliness definitions, called stochastic TCP friendliness (STF). STF greatly expands the design space of TCP-friendly traffic control protocols, while still effectively maintaining the desired fairness of the Internet. To demonstrate the expanded design space, we also develop a new congestion control protocol, called TCP-friendly CBR-Like Rate Control (TFCBR), for multimedia streaming applications which do not require a high sending rate but prefer a smooth sending rate on a time scale of tens of seconds. TFCBR is stochastically TCP friendly, however, it is not TCP friendly by the current definition.     

一种简便的饮用水除铀方法及其机理

本文介绍一种利用原水中含有的无机盐,加入廉价的化学试剂除去饮用水中微量铀的简便方法。并对其除铀机理进行了探讨,证明除铀主要是以软化水过程中产生的氢氧化镁表面吸附共沉淀机理进行的。     

Pd/Mg(OH)2 Heterogeneous Nanocatalysts Synthesized by a Facile One-Pot Hydrothermal Method for CO Direct Esterification to Dimethyl Oxalate

Catalysis Letters - Pd-based heterogeneous nanocatalysts have wide application in chemical industry. However, the traditional synthesis process contains multi-steps such as impregnation, dry,...