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In this paper,a design method of two dimensional Linear Phase Nearly Perfect Reconstruction filter banks based on a new class of cosine modulation systems is presented,which can be described as follow: firstly,the Parks-McClellan algorithm is adopted for designing the prototype filter,then by employing cosine modulation,a series of analysis and synthesis filters can be obtained,accordingly a one-dimensional LP-NPR filter banks can be constructed;Secondly,cascading two one-dimensional LP-NPR filter banks in the form of tree structure and using the unimodular transformation,a two dimensional nonseparable LP-NPR filter banks can be obtained.

提出了一种基于一类新余弦调制系统的二维线性相位-近似完全重构滤波器组的设计方法，设计过程分为两个步骤：首先采用Parks-McClellan算法来计原型滤波器，再经过余弦调制能到一系列的线性相位分析和综合滤波器，从而可以构造一维LP-NPR滤波器组；然后利用树状结构来结合两个一维LP-NPR滤波器组，并运用单位模变换，可以得到二维不可分离LP-NPR滤波器组。

Methods Two methods,ADAPCO's RAMP System and MAS's VecTest kits were selected. The sensitivity and accuracy of these two methods and its cross-reaction with Japanese Encephalitis virus were tested. These two methods also were used to detect WNV in wild mosquitoes.

选择两种快速检测方法VecTest试剂盒和Ramp系统，对其检测WNV的敏感性、精确性以及与流行性乙型脑炎病毒的交叉反应进行研究，同时对采自北京市野外的蚊虫进行WNV检测。

There are fourteen chapters, including introduction, plane stress and plane strain, two-dimensional problems in rectangular coordinates, two-dimensional problems in polar coordinates, photoelastic and moire experimental methods, two-dimensional problems in curvilinear coordinates, analysis of stress and strain in three dimensions, general theorems, torsion, bending of bars, axisymmetric stress and deformation in a solid of revolution, thermal stress, the propagation of waves in elastic solid media, at last there is an appendix on the application of finite-difference equations in elasticity.

全书共十四章，包括绪论、平面应力和平面应变、直角坐标中的二维问题、极坐标中的二维问题、光弹性与云纹实验方法、曲线坐标中的二维问题、三维应力和应变问题、一般定理、简单的三维弹性问题、扭转、杆的弯曲、回转体中的轴对称应力和变形、热应力、弹性固体介质中波的传播，最后有一附录，讲述差分方程在弹性理论中的应用。

When propagating light\|ray passes through two fixed points in the gradient index mediums and a cuspidal variable\|point （at this point the trace equation of propagating light\|ray is non\|differentiable） at the borderline of two different GRIN mediums, the mathematical relationship, which the trace equation of propagating light\|ray and borderline equation of two different GRIN mediums should satisfy, is derived by the Fermat's principle and calculus of variation.

当光线通过梯度折射率介质中两个固定点和两个GRIN介质界线上的可动尖点（光线轨迹方程的不可微点）时，由费马原理和变分法运算推得传输光线的轨迹方程与两种不同GRIN介质的界线方程应满足的微分关系式。

Two ferrocenyl and trimethylsilyl substituted cyanohydrin ethers have been prepared by the addition of trimethysilyl cyanide to two acetyl-substituted ferrocenes: 1-(1-cyano-1-trimethylsilyloxyethyl)-ferrocene (1) and 1, 1'-bis(l-cyano-1-trimethylsilyloxyethyl)ferrocene (2). The structures of these two compounds were characterized by elemental analysis, IR, 1H NMR and X-ray crystallography.

通过两种取代的乙酰基二茂铁与三甲基氰硅烷的加成反应，得到两种取代二茂铁基三甲基硅烷基氰醇醚的晶体：1-（1-氰基－1-三甲基硅烷氧基乙烷基）二茂铁(1)，1，1-二（1-氰基－1-三甲基硅烷氧基乙烷基）二茂铁(2)，用X射线单晶衍射、元素分析、红外光谱和核磁共振氢谱对分子结构进行了表征。

The optical source device includes a flexural luminous tube used to produce optical source and can compensate the brightness of the two ends by the flexural structure of the two ends, and a shroud component installed on flexural part of the two ends of luminous tube to defilade part of light from luminous tube.

该光源装置包含：一弯曲灯管，用来产生光源，并藉由两端的弯曲结构补偿两端的亮度；以及一组遮蔽组件，安装于灯管两端弯曲的部分位置来遮蔽该灯管的部分光线。

In Two-Transistor Flyback Converter circuit, a power semiconductor device in Flyback Converting circuit has been replaced by two power semiconductor devices which parallel connected with an ultra-fast diode with soft recovery characteristics. Two-Transistor Flyback Converter can reduce greatly the switching stress of the power switch and does not need to degausser, suitable for high input voltage Switching Power Supply.

反激变换是从Buck-Boost变换演变而来的，将反激变换电路中的单个功率开关管用两个替代，并在每个功率开关管上并联一十箝啦的快恢复二极管而形成的双晶体管反激变换电路，能大大降低功率开关管承受的开关应力，且不需要消磁电路，非常适用于高输入电压的开关电源。

New type of water chemistry for utility drum boiler and its principle and characteristic Two kinds of water chemistry's main principle and characteristic are detailedly analyzed. Against the problem of high eroding speed, high Fe content in feed water and boiler water, high scaling speed, short chemical cleaning interval, needing poisonous chemical deoxidant, etc for drum boiler's deoxidization water chemistry and difficulty of using oxidation water chemistry, a new type of water chemistry is put forward on the basis of analyzing the characteristic of whole power station's water steam cycle system, principle of two kinds of water chemistry and their practical effect in every cycle stage. Considering two water chemistry's merit, a new water chemistry called Limited Oxidation Water Chemistry is put forward, which is a local slight oxidization no-deoxidant water chemistry. And the proposed method's principle, control parameter, applying condition, start-lay up and emergency measures are initially calculated and analyzed.

三、新型汽包炉水化学工况的提出及其原理和特点详细分析了国内外现行两大类水化学工况处理的核心原理和特点，针对现行汽包炉还原性水化学工况处理所存在的系统腐蚀速度相对较大、给水和炉水铁浓度高、锅炉结垢速度快、机组酸洗间隔短、无法避免有毒化学除氧剂的使用以及氧化性水化学工况在汽包炉机组上应用的困难等问题，在详细分析电站整个水蒸汽循环系统的特点、两类水工况处理的原理和对循环中各段处理的实际效果等的基础上，综合两者的优点，提出了一种新型的局部轻微氧化性无除氧剂汽包炉水化学工况－"汽包炉有限氧化性水化学工况"处理原理，并初步计算、分析和确定了该种新型水化学工况的主要工艺控制参数、应用条件、启停与紧急情况处理等。

When the moving-star arrived to the side of another star, both two stars(star-A and star-B) began to move in a circle orbit that the two stars are constantly at the two terminals of a diameter of the circle.

当它移到另一颗星星的一侧时，这两颗星星顺势互相环绕，各绕了半周，移过来的那颗绕到了另一侧。

Lastly, two-phase flow flied is studied under spinning (60n/s and 100n/s) condition, integral calculation of the two-phase flow is completed in the spinning SRM combustion chamber and nozzle, and the behavior and varieties of parameters of different diametric particles are studied in spinning internal flow flied thoroughly. The analysis of result and discussion are presented by comparison to two-phase flow flied of no-spinning case.

最后重点研究旋转情况下(25n/s和60n/s)固体火箭发动机两相流场，进行旋转固体火箭发动机燃烧室—喷管一体化两相流场数值模拟，分析了发动机内不同颗粒的运动及参数变化规律，并与不旋转两相流场对比进行结果分析和讨论。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。