高精度步进压印机热误差的建模分析

为了消除由紫外光曝光所引起的步进压印机的热误差，以提高压印机的套刻对准精度，运用逐步回归分析法选取了压印机上温度测量点的数量，将压印机上布置的温度传感器从15个减少到6个，并建立了压印机温度测量关键点处的温度与压头在x、z方向热误差关系的数学模型．实验结果与模型计算结果的对比分析表明，模型的热误差预测精度在x方向可以达到899／6，而在z方向可以达到939／6．应用表明，该方法是一种在压印机热误差建模中选择温度测量关键点的有效方法，可避免热误差建模过程中的变量耦合问题，从而提高了模型的精确性．     

WHOLLY-AROMATIC COPOLYESTERS CONTAINING IPA, 2.6-NDA, TPA, CLHQA AND PABA MONOMERS

The crystallinities, thermal properties, liquid crystal properties and rheologic properties oftwo series of the aromatic copolyesters are studied. One of them is composed of IPA, 2,6-NDA,CLHQA, PABA and. the other composed of TPA, 2.6-NDA, CLHQA, IPA. The results showthat the crystallinities of the aromatic copolyesters are relatively low and the melting point of thecopolyesters decreases with an increase of the unsymmetrical contents. These two series of aro-matic copolyesters are both suitable for the conventional melt spinning process and have a goodfiber forming property and a good thermal stability. The viscosities of aromatic copolyestermelts are greatly affected by the shear rate, hence the so-called" thinning under shearing" phe-nomenon. The melts have a rather high viscosity flow activation energy and a relatively lowelasticity.     

园艺业在新疆绿洲建设中的作用与可操作性问题的探讨（综述）

概述了新疆绿洲和新疆园艺业的情况,从经济效益、社会效益、生态效益三个方面较全面地论述了园艺业在新疆绿洲建设中的地位和作用,旨在强调其在绿洲中的重要性,同时探讨性地提出了园艺业在新疆绿洲中健康发展的可操作性体系。     

一种基于H∞技术的新型鲁棒励磁控制器

论述了微机励磁控制器硬件电路设计及控制规律,微机励磁控制器硬件采用模块化设计,四种控制规律：比例式、比例式＾＋电力系统稳定器、线性最优控制、基于Ｈ∞技术鲁棒性控制。通过对单机无穷在系统小干扰、大干扰仿真表明,线性最优控制和基于Ｈ∞技术鲁棒控制较前两种控制规律为优,它们不仅能有效的提高系统的静态性能,而且在大干扰情况下,也能够为系统提供阻尼,改善系统的动态品质。     

只用两个偏振态的量子密码术方案

本文提出一种基于海森堡测不准关系的、只用两个非正交偏振态光子的量子密码术新方案,对其原理和防窃听性进行了详细的讨论,并和国际上流行的几种方案进行了比较。     

Inheritance and expression ofEsterase-1 allozymes inPeromyscus leucopus

Summary We analyzed inheritance of 5Es-1 alleles inP. leucopus and found them to be co-dominant and segregating from a single autosomal locus, thereby verifying assumptions of Mendelian inheritance imfield data. We also described an allele that is silent in hemolysate, but is active in liver extract.Acknowledgment. Laboratory analysis was partially supported by a grant-in-aid (No. 0171-02-240-76) to Kaufman from the Research Foundation of State University of New York.     

Periodic fluctuation in burst amplitude during ‘fictive locomotion’ in the cat

Summary In decorticated unanaesthetized and paralysed cats, locomotor bursting may develop spontaneously on hindlimb motor nerves. In defined experimental conditions, the amplitude of successive rhythmic bursts may fluctuate periodically as if a secondary oscillation was superimposed upon the basic locomotor rhythm. The possible meaning of such amplitude fluctuation is discussed in connection with present data about the generation of locomotion.     

Rapid cold hardening process of insects and its ecologically adaptive significance

In contrast to overwintering cold hardening, a rapid cold hardening process has recently been described in insects. This process can rapidly enhance cold tolerance of insects in several hours or even minutes. The characteristics of rapid cold hardening include inducing conditions, cold hardening effects, and fitness costs. Physiological and biochemical mechanisms of rapid cold hardening include rapid changes in the phospholipid composition and the increase in hemolymph osmolalities, polyols production, proline and cold-induced proteins. Moreover, there are different views about the ecologically adaptive significance of rapid cold hardening in insects. This paper reviews research results about rapid cold hardening of insects since 1987, focusing on forms of cold injury, strategies of cold tolerance, and definitions, characteristics, physiological and biochemical mechanisms and adaptive significance of rapid cold hardening.     

IMP在电厂监控系统中的应用

对于电厂数据采集环境比较复杂、信号分散的情况，可采用隔离测量组件（ＩＭＰ）作为分散式数据采集的前瑞，直接安装在传感器或变送器的附近。其具有防磁、防尘、防水、防震等性能。ＩＭＰ还可以对采集的数据就地进行数字化加工及一些预处理，通过Ｓ－网络进行数字量的传输到主计算机。避免了由于信号电平较低，传输距离及较远时带来的信号衰减及噪声干扰。