成双的

along with the development of digital technology,digital filters are widely used in many fields,this paper introduces how to design a iir digital notch filters in matlab environment.the design of digital notch filters can be achieved through three steps:firstly,the design of analog lowpass filter; secondly,it is analog lowpass to analog band stop filter conversion;at last,using the bilinear transformation make the analog notch filters change into digital notch filters.the paper also introduces how to design the transfer function of the digital notch filters using all the zeros and farthest points at the same time,it also introduces the program of the digital notch filters under butterworth analog lowpass prototype.

摘 要：随着数字技术的发展，数字滤波器在许多领域得到广泛的应用。研究一种在matlab语言环境下设计iir数字陷波滤波器的方法，在数字陷波滤波器设计过程中，先进行模拟低通滤波器的设计，然后进行模拟低通/模拟带阻滤波器转换，最后采用双线性变化法将模拟陷波滤波器转化成数字陷波滤波器。提出一种用所有零点和极点来表达数字陷波器传递函数的方法，同时给出以巴特沃斯模拟低通为原型设计数字陷波滤波器的程序。关键词：无限冲激响应；巴特沃斯滤波器；数字陷波滤波器；matlab；双线性变换

Used in shaping process of brick production , the treated clay will be plastic extruded by up stage then via vacuum room into down stage, estruding into solid or hollow clay column of required cross section and shape which then cut into greenbrecks by green breck cutter.

JKR40/40型双级真空挤砖机适用于砖瓦生产成型工段，可将经过处理的原料经过上级增塑挤出后落入真空室抽取空气后再经过下级挤成规定断面的实心或空心坯条，再经过切坯机制成一定规格的砖坯。

Clinical trials show a tendency for those with Cyclothymic Disorder, particularly those with an early onset, to develop bipolar disorder over time.

由於症状轻微，常常没有被诊断出来常常诊断为双极性二型的病人回想起他们早有可以诊断为轻度躁郁症的症状临床试验显示轻度躁郁症尤其是早发型的经过时间会转变成躁郁症15% to 50%会转变成躁郁症

In Zhong Shan's artworks,"Double images" art has man's appearance and figure as the subject, and expresses in the form of "diptych". The two works are placed side by side, and can be compared and observed, expressing the meaning of two in one and the relationship between concepts such as the internal and the external, ego and alter ego, real image and virtual image, sense and sensibility, spirit and material, double image and corresponding and so on. His art shows that the artist is reflecting the contemporary society from a special view angle and that the symbols bearing the weight of human social and historical culture and contemporary ideology occur in various changing characters, showing the colorful world of today.

在艺术家钟山的艺术中，"双相艺术"是指以人物等容貌、外形为表现主体，以双联成对形式这种新的阐释方式呈现，它们相互并列对置，可进行比较、审视，共同表达一体两面、内在与外在、本我与异我、实象与虚象、理性与感性、精神与物质、双像与对应等理念的关系，传达出艺术家以另类视角审视当代社会，体现那承载着人类社会和历史文化脉络及当代流行意识形态的符码，形形色色交织演绎在万千变化的形象上，展现着今天这个缤纷万象的世界。

The approach is based on the principle that the a pa rticle will form double points on the image plane when the particle is out of fo cus in an optical system with a two pinhole lens.

该方法是当利用双孔透镜成像时，单点粒子在离焦光学成像系统中会形成包含粒子空间信息的两点像，根据粒子像在像平面上的位置和间距可以获取空间粒子的三维空间位置。

0M/s.(4) The barchans dunes developed in narrow un-modal wind regime, the value of RDP/DP is greater than 0.8; the compound longitudinal dunes mainly developed in modal wind regime whose value of RDP/DP is about 0.55; the dome dunes developed in those areas that have directional winds and their force is balanced; and the star dunes mainly distributed in areas which have wavy terrain or approach mountains.

4塔克拉玛干沙漠新月形沙丘及沙丘链主要是在窄单峰风环境中发育而成，RDP/DP值一般都在0.8以上；复合型纵向沙垄主要是在双峰风况条件下发育而成的，RDP/DP值在0.55左右：穹状沙丘形成于均衡的多风向地区；而金字塔沙丘一般都形成于下伏地面微有起伏或邻近山岭的地带。

The barchans dunes developed in narrow un-modal wind regime, the value of RDP/DP is greater than 0.8; the compound longitudinal dunes mainly developed in modal wind regime whose value of RDP/DP is about 0.55; the dome dunes developed in those areas that have directional winds and their force is balanced; and the star dunes mainly distributed in areas which have wavy terrain or approach mountains.

塔克拉玛干沙漠新月形沙丘及沙丘链主要是在窄单峰风环境中发育而成，RDP/DP值一般都在0.8以上；复合型纵向沙垄主要是在双峰风况条件下发育而成的，RDP/DP值在0.55左右；穹状沙丘形成于均衡的多风向地区；而金字塔沙丘一般都形成于下伏地面微有起伏或邻近山岭的地带。

In this paper, we report the calculation of single line-image and double lineimage for various configuration of diffractive optical element, which were designed as one- dimensional plane configuration of bar- shaped pure- phase from the principle of the optical equal- path compensation.

报道以一维平面阶梯条形纯位相结构，用等光程补偿的物理概念出发，计算了单线与双线象的衍射光学元件的多种构形，获得了与理想衍射线象符合的光强分布；同时发现双线象时会出现噪音光强小峰，这在精确成象时仍是要设法避免的。

As the maneuverability of the model of 800 t ship with double tail fins didn′t meet the design standard,this article turned the twin skeg of the models into tail-shaft strut,and then made tur-ning tests and Z shape tests.

针对某一采用双尾鳍形式的800 t级排水船在进行自航模试验时出现操纵性能不能满足设计要求的情形，文中将其尾部的双尾鳍改成轴支架，并在某露天操纵性水池中，对改进后的自航模进行了回转和Z形操纵试验，通过对实验结果进行比较发现合理设计轴支架的大小和安装位置能够较好地改善800 t级排水船的操纵性能，并能够满足给定的船舶操纵性能设计要求。

For double jet method, effects of used solvent, shape of stirrer, adding reactant position, reaction temperature, excessive silver ion concentration in reaction solution and adding rate on the nucleus formation, and growth of silver behenate crystal were systematically studied.

本文分别采用单注沉淀法和双注沉淀法制备了山嵛酸银晶体，通过对两种制备方法的对比及优选，最后确定双注沉淀法更适合制备细粒径的山嵛酸银，通过采用SEM、TEM等对山嵛酸银晶体形貌的表征发现，制备山嵛酸银所使用的溶剂、搅拌方式、加料的位置、反应温度、反应初始液中银离子浓度及加料速度等，均对山嵛酸银的晶体成核与生长有一定的影响。

She gently rebuff ed him, but agreed that they could be friends

她婉言拒绝了，但同意作为朋友相处。

If in the penal farm, you were sure to be criticized.

要是在劳改农场，你等着挨绳子吧！