2.题二图所示为搜索式超外差接收机原理图,其侦察频段为f口f2=10002000MH,中放带宽为4,=2MH。现有载频为1200M,脉冲为lμs的常规雷达脉冲进入接收机 (1)画出频率显示器上画面及信号波形,说明波形包络及宽度与哪些因素有关? (2)中频频率f及本振频率f应取多大,为什么? (3)画出接收机各部分频率关系图

REMINDER: Computer Lab #1 is due on October 8 REMINDER: Quiz 1 will be held from 7: 30-9: 30 p. m. Tuesday, October 14 in Walker Memorial. The quiz will cover material in Chapters 1-3 of o W, Lectures and Recitations

1、(10分)设集合M=123456,789},从中任取3个互异的数排成一个数列,求该数列为等比数列的概率. 2、(10分)从9,-7,0,1,2,5这6个数中,任取3个不同的数,分别作为函数y=ax2+bx+c中的abc的值,求其中所得的函数恰为偶函数的概率

一、试验目的及任务 l、掌握传热膜系数α及传热系数K的测定方法。 2、通过实验掌握确定传热膜系数准数关联式中的系数A和指数m、n的方法。 3、掌握测温热电偶的使用方法

This lecture: Mount pp 1-7, 29-35, 45-48, Next lecture: Mount pp 8-9, 65-89, 96-115, +more TheProteinDataBank(pdb-http.://ww.pdb.org/)isthesingle worldwide repository for the processing and distribution of 3-D biological macromolecular structure data Berman, H. M, J. Westbrook, Z Feng, G. Gilliland, T N. Bhat

1、大小为56~76×36~40m 2、椭圆形,壳薄,无色透明 3、内多含4个细胞,卵壳与卵细胞之间有明显空隙

本部分由 Math Type工具制作,若要修改,请确定安装了 MathType 第二十章重积分 §2重积分化累次积分 313.5(1) k+1 (2)1(3)(4)=a4(5)-(e2-1)(6 (k+1)(m+1+-)

Problem Set 3 Prof. Gene Chang (For Ph. D students, due on Dec. 28th in the class, or TA's office. For M.A. students, due on Dec. 26th, in the class or TA's office. Late turn-in may result in a penalty in the grade) 1. Kland is a Robinson Crusoe type economy. Robinson, as the consumer and the owner of the firm, has the utility function U(x,) =aIn x+ BInI, where is leisure. Robinson's endowment

野外测绘中采取水样必须遵守下列规则: (1)要从水面以下0.2~0.5m处取样 (2)在停滞的水体或水中采取水样,应将死水抽去后,采取新鲜水样;采取河水水祥,应在水流较缓的地段采取; (3)在取祥前应将已洗净的水样瓶用所取之水仔细冲洗2~3次;

轨道:与氢原子类似,其电子运动状态可描述为1s,2s,2px2p2p3s。 能量:与氢原子不同,能量不仅与n有关也与有关;在外加场的作用下,还与m有关