次波

The paper presents a linear transient solution for the solitary wave generated by a piston-type paddle in a finite flume based on the boundary condition derived by Dean and Dalrymple (1991). The wavemaker problem is simplified by decomposing the wave potential into two parts. One is the evanescent wave and the other is progressive wave. The possible solution for the evanescent wave is expressed in form of the Fourier series.

本文根据Dean与Dalrymple（1991）描述造波水槽内部之线性边界条件，将水槽内部之流速势分为振荡波与前进波以简化问题，再以Fourier级数展开，可将问题化为二非齐次常微分方程式，在给定造波初始条件的情况下即可解析有限长度造波水槽自静止开始造波一段时间后停止之线性暂态解。

In chapter 3,we study the Zakharov-Kuznetsov-Modified Equal-Width equation by employing the extended Jacobi elliptic function expansion method and obtain some new solutions of Jacobi elliptic function type of the ZK-MEW equation.;Secondly,using sn-cn method,we study K(m,n,1) equation and obtained some new exact solutions when k=s=3,especially obtained abundand solitary solutions and trigonometric function solutions when m→0 and m→1;In chapter 4,Painleve singular analysis was applied to nonlinear PDE with variable coefficients.

第四章将Painleve奇性分析方法应用到带阻尼项的变系数Burgers方程中，并得到了该类Burgers方程具有Painleve性质的条件，给出了该类Burgers方程的Backlund变换，用所得Backlund变换得到了若干精确孤立波解，包括奇异孤立波解，这些解不等同于行波型孤立波解；用齐次平衡法得到了对数型DBM方程的Backlund变换，并获得了DBM方程的各种孤立波解，包括尖峰孤立波解和奇异尖峰孤立波解。

Apollo was the god of music and poetry.he could stir up all feelings.these feelings are expressed in lofty songs.with his lyre of gold and the sweet accents of his godlike voice heled the choir of the muses at olympus.the pleasant music from his lyre was so exciting that stones marched into their places in rhythmic time and of their own will when he helped poseidonbuild up the walls of troy.on one occasion,invited to a contest by the human musician marsyas,he won and then flayed him to death for his pride.on another occasion,he lost out topan at a musical contest and turned the ears of the judge ,king midas, into those of an ass.

他可唤起人们倾注于圣歌中的各种情感。在奥林波斯山上，他手拿金质里拉，用悦耳的音调指挥缪斯的合唱。当他帮助波塞冬建造特洛伊城墙时，里拉奏出的音乐如此动听，以致石头有节奏地、自动地各就其位。有一次他接受凡人音乐家马斯亚斯的挑战参加一次竞赛。战胜对方后，他将对手剥皮致死以惩罚他的狂妄自大。在另外一次音乐比赛中，因输给了潘神，他就将裁判迈尔斯国王的耳朵变成了驴耳朵。阿波罗的儿子俄耳甫斯继承了父亲这方面的才能。

Apollo was the god of music and poetry.he could stir up all feelings.these feelings are expressed in lofty songs.with his lyre of gold and the sweet accents of his godlike voice heled the choir of the muses at olympus.the pleasant music from his lyre was so exciting that stones marched into their places in rhythmic time and of their own will when he helped poseidonbuild up the walls of troy.on one occasion,invited to a contest by the human musician marsyas,he won and then flayed him to death for his pride.on another occasion,he lost out topan at a musical contest and turned the ears of the judge,king midas,into those of an ass.

阿波罗是音乐神和诗神。他可唤起人们倾注于圣歌中的各种情感。在奥林波斯山上，他手拿金质里拉，用悦耳的音调指挥缪斯的合唱。当他帮助波塞冬建造特洛伊城墙时，里拉奏出的音乐如此动听，以致石头有节奏地、自动地各就其位。有一次他接受凡人音乐家马斯亚斯的挑战参加一次竞赛。战胜对方后，他将对手剥皮致死以惩罚他的狂妄自大。在另外一次音乐比赛中，因输给了潘神，他就将裁判迈尔斯国王的耳朵变成了驴耳朵。

Apollo was the god of music and poetry.he could stir up all feelings.these feelings are expressed in lofty songs.with 你好s lyre of gold and the sweet accents of 你好s godlike voice heled the choir of the muses at olympus.the pleasant music from 你好s lyre was so exciting that stones marched into their places in rhythmic time and of their own will when he helped poseidonbuild up the walls of troy.on one occasion,invited to acontest by the human musician marsyas,he won and then flayed 你好m to death for 你好s pride.on another occasion,he lost out topan at amusical contest and turned the ears of the judge,king midas,into those of an ass.

阿波罗是音乐神和诗神他可唤起人们倾泻于圣歌中的各类感情在奥林波斯山上，他手拿金质里拉，用悦耳的音调批示缪斯的合唱当他帮助波塞冬制作特洛伊城墙时，里拉奏出的音乐云云动听，乃至石头有节拍地、自动地各就其位有一次他接管常人音乐家马斯亚斯的挑战参加一次竞赛打败对于方后，他将敌手剥皮致死以惩罚他的傲慢自负在另一次音乐比赛中，因输给了潘神，他就将裁判迈尔斯国王的耳朵变成了驴耳朵

Long-path multiple: A seismic reflection whose travel path is much longer than required for a primary reflection from the deepest interface reached.

全程多次反射波：传播路径比来自最深界面的一次反射波路径长得多的地震反射波。

Through Hilbert transform, a signal's plane trace can be get. There are two frequencies in the tested signal, so the signal's plane trace may be looked as the track of the out pole's end when two poles rotate around parallel axles. Using the knowledge of motion synthesis in theory mechanics, a formula to describing the change of plane trace's step length and angle for two-frequency be get. So we may prolongate the tested signal's plane trace from the echo's initial arriving moment, and get a certain length of the signal's prolongation.

通过Hilbert变换可得到测试信号的平面迹线，测试信号中只含有两个频率成分，视为双频信号，双频信号的平面迹线相当于两连杆绕平行轴转动时外杆杆端迹线，利用理论力学中运动合成和瞬心知识，推导出双频信号平面迹线步长平方满足余弦线性复合函数，而迹线转角可视为线性变化，据此可对回波到来之前的测试信号平面迹线作延长，得到一定长度的信号延展段，信号延展段与实测段作差可得到一次、二次回波的第一个波峰值。

Careful analysis on NBE can facilitate nowcasting of severe weather events and further understanding of their evolution. After detailed study on three cases concerning with NBE, it is concluded:(1) NBE triggered by fast moving echo in upstream is an important indication of disastrous wind;(2) NBE can develop into severe storm under proper conditions. There are often two stages during this kind of growing: the first is developing of initial echo, the second is snap growing of echo core;(3) Doppler radar reflects outflow of downburst as a nearly ringed NBE. Inside look on downburst can be obtained combining NBE with other data.

文章结合发生在上海的3次强对流天气个例，详细分析了弱窄带回波在分析和预报强对流天气中的作用，得出以下结论：（1）上游移动强回波的出流边界导致的弱窄带回波是大风预警的重要判断参考；（2）在合适的层结状态和抬升条件下，弱窄带回波会强烈发展，并导致局地雷雨大风，这类强对流天气的发展有两个比较重要的阶段：弱窄带回波上初始回波的发展和回波跃增；（3）下击暴流造成的地面出流在雷达回波上表现为近似圆弧的弱窄带回波，这种弱窄带回波与其他雷达观测特征以及地面观测相结合，有助于对产生下击暴流的对流云的发生发展过程进行细致分析。

A tripartite array of infrasonic measurement in Changping county of Beijing was arranged using three CSH-1 infrasonic receivers. The infrasonic signals (P-t curve and wave vector) produced by meteor shower from Leo on November 17 in 1998 were observed.

采用三台CSH-1型次声接收器，在北京昌平县布置了一个次声测量三点阵，观测到1998年11月17日狮子座流星雨产生的次声波P-t曲线和波速波向图。

Wave after succeeding in escaping make track for of seal shot once the wave met to compare his shape short and small emperor penguin, they were brave, optimism, love help other people and solidify again very intelligent, they all appreciated a wave very much of dance, they decided to help a wave after knowing wave the career of the wave.

有一次在逃脱海豹的追击后波波遇到了比他身材矮小的帝企鹅，它们勇敢、乐观、爱帮助别人并且团结又很聪明，它们都很欣赏波波的舞蹈，在知道了波波的经历后它们决定帮助波波。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。