信号

But, in the natural and artificial signal, a lot of signal phases don\'tvary linearly with time, for example, we usually use chirp signal in the radar technology,frequency step signal, linear modulation component of the ground echo in the SARtechnology, linear modulation component of the moving target echo, linear modulationcomponent while the airborn radar detecting the moving target, etc.

在自然界和人工信号中，许多信号的相位变化并不是随时间一次方变化，如雷达技术中常用的线性调频信号，频率步进信号，另外，SAR 技术中，地面回波所含有的线性调频分量，ISAR技术中，运动目标的回波所含有的线性调频分量，机载雷达探测运动目标时的线性调频分量，等等；傅里叶变换对此类信号分析所得的结果是信号在不同频率点上的能量分布，即信号在基函数上的投影。

Third, the discussion of the corresponding relationship of the real angles to the apparent real angles is performed, the asymptotic bias and MSE of real angles are given. Fourth, based on above conclusions, the analysis of two typical cases is made by numerical analysis and computer simulation: Case A when the impinging signals are divided into desired signals and interfering signals: it is shown that similar to Cyclic estimation of DOA, the smaller the separation between interfering direction and signal direction, in general, the smaller the estimation variance.

首先，研究了无穷快拍时信号数目有误的最大似然估计，引入了视在真实角度的概念；其次，导出了视在真实角度最大似然估计大样本时的分布以及渐近均方误差的解析表达式，而且还证明了：Stoica性能分析结果是现在的分析结果在信号数目准确时的特例；第三，讨论了真实角度与视在真实角度的关系，给出了真实角度的渐近偏和渐近均方误差；第四，依据前面的结果，利用数值分析和模拟实验的方法对两种典型情况做了分析： 1 在入射信号被分为干扰信号和所需信号情况下：结果表明：与CyclicDOA估计一样，干扰方向与所需信号方向靠的越近，所需信号估计的方差越小，越远离，方差越大。

The signal test table is established where the Labview signal collection system collects the concrete exit pressure signals, the piston displacement signals of concrete cylinder and the main hydraulic signals. The real measured signals are processed through arithmetic equilibrant filter of the data signal processing method. The pumping efficiency and relative error of real time output are measured by two output calculation methods.

搭建了实测信号试验台，通过Labview信号采集系统现场采集混凝土出口压力信号、混凝土缸活塞位移信号和主液油信号，采用算术平均滤波法的数字信号处理方法对实测信号进行处理，通过两种排量计算方案检测泵车实时排量的泵送效率和相对误差。

It is the key factor regulating programmed cell death in pathogen,evocator and hormone responses.H_2O_2 has also been proved to play the signal role in defensive response to environmental stresses.H_2O_2 is known of directly regulating the expressions of numerous genes and some of these genes relate to plant defense and hypersensitive response.H_2O_2 also interacts with other signal systems,especially hormone signal system,and forms upstream or downstream components of hormone-mediated signal-transmitting passageways;more importantly,H_2O_2 also work to exert influence on or modify other secondary signals such as calcium signal between which and H_2O_2 many interactions take place;and both of these two signals regulate interactive tolerances of plants.

已知H2O2直接调节无数基因的表达，其中有些基因与植物防御和超敏反应有关。H2O2还与其它信号系统特别是激素信号相互作用，是激素介导的信号传导通路上的上游或下游组分；更重要的是H2O2还影响和修饰其它第二信使如钙信号的作用，在H2O2信号和钙信号之间发生众多的交互作用且这两种信号分子都调节植物对多种胁迫的交互耐性。

The CC MRI findings are characterized mainly by:(1)frequently-encountered multiple circular foci during the cysticercus survival:small excentric spotty images of the mural cysticercus scolex :slightly high signs on T1WI and middle-lower signs on T2WI;lower signs on T1WI and high signs on T2WI of the capsular liquid;lower signs of the cerebrospinal fluid but relatively high signs of the capsular liquid on FLAIR;and unremarkable peripheral edema;(2)scolex disappearance,enlarged capsular cavity and remarkable peripheral edema during cysticercus degeneration and necrosis;(3)lower signs on T1WI and T2WI and peripheral edema disappearance after the focal calcification;(4)findings shown by the enhanced scanning:strengthened (24/36) or non-strengthened (12/36) cyst-wall circular images;strengthened (22/36) or non-strengthened (14/36) small intracapsular spotty images;(5)cerebral-ventricular type often occurring in the third and fourth ventricles:one case in the third ventricle (1/36) and three cases in the fourth ventricle (3/36),all of suffered from obstructive hydrocephalus;(6)hydrocephalus caused by arachnoid adhesion (2/36) in meningeal type.

结果 脑实质型18例，脑室型4例，脑膜型3例，混合型11例，主要MRI特点：(1)囊虫存活期，病灶呈圆型，多发常见，附壁囊虫头节呈偏心型小点状影，T1WI呈略高信号，T2WI呈中低信号；囊液T1WI呈低信号，T2WI呈高信号；在FLAIR上脑脊液呈低信号，而囊液呈相对高信号；周围水肿不明显。(2)囊虫退变坏死期，头节消失，囊腔扩大，周围水肿明显。(3)病灶钙化后，T1WI及T2WI均呈低信号，周围水肿消失。(4)增强扫描表现为：囊壁环状增强(24/36)，或不增强(12/36)；囊内小点状影增强(22/36)，或不增强(14/36)。(5)脑室型：常发生于第三、四脑室，其中第三脑室1例(1/36)，第四脑室3例(3/36)，均引起阻塞性脑积水。(6)脑膜型：因蛛网膜粘连，而引起脑积水(2/36)。

Interference is most difficult to be avoided while measuring the weak signal, Especially when the signal is only at microvolt level.X9313 is a kind of digitally controlled dissurbacne potentiometer produced by Xicor company.We succeed in using it to solve the problem that the signal is too strong, and get the useful signal in a weak signal measurement device.

微信号检测中最难避免的就是干扰问题，特别是在信号仅为微伏级时，信号相对于干扰来说，几乎被完全淹没，因此，研究如何在干扰信号很大的情况下尽可能地检测出有用信号有着极其重要的意义。X9313是Xicor公司推出的一种数字电位器，在某微弱信号检测装置中，采用X9313可成功解决干扰信号过大的问题。

The circuit comprises a comparison circuit, a negation gate and a first coincidence gate, wherein the comparison circuit is used to output read screen signals of a storage unit corresponding with bus signals of a second port address, the negation gate is used to inverse the read screen signals of the storage unit which are corresponding with the bus signals of the second port address, one input end of the first coincidence gate receives the read screen signals of the storage unit which are corresponding with the bus signals of the second port address after being inversed, the other input end of the first coincidence gate receives the read enable signals of a second port, and the output end of the first coincidence gate is connected with the read enable end of the second port.

所述电路包括：比较电路，用于输出第二端口地址总线信号对应的存储单元读屏蔽信号；非门，用于对第二端口地址总线信号对应的存储单元读屏蔽信号进行非运算；第一与门，第一与门的一路输入端接收非运算后的第二端口地址总线信号对应的存储单元读屏蔽信号，第一与门的另一路输入端接收第二端口的读使能信号，第一与门的输出端连接第二端口的读使能端。

Positive and negative interval divisions of dynamic pressure signal was proposed. The differences of weighted signal sums,signal mean values,signal peaks of every two successive intervals were selected as the features of leak signal,and their calculations and relative scaling transformations were presented. The feasibility criteria for lengthwise and breadthwise evaluation of leak signal features were presented,and evaluation was done with features extracted from field data and the feasibility was verified.

提出了把动态压力信号作正负区间划分、把相邻区间信号累加值差分、相邻区间信号均值差分和相邻区间信号峰值差分作为泄漏信号识别特征的特征量计算方法和相对量化方法，分析了泄漏信号特征量的横向、纵向合理性评判依据，并以此对从实际泄漏信号中提取得到的特征量进行了检验，验证了特征量提取方法的合理性。

The signals look like noncontinuous beads on the DNA fiber,which consist of multi-copy and arrange tandemly.Fiber-FISH results with 45S rDNA probe showed that an average signal length is about 3～11μm in many tandem copy sequence(measure number,n=8),so we estimated the size of each copy to be approximately 11～30kb in cotton genome.There are dual signals on each end of the mitosis metaphase chromosomes and pachytene chromosomes hybridized with telomere DNA probe.The signals also look like non-continuous beads on the DNA fiber,the length is about 1～9μm,so we estimated the size is about 4～27kb.The signals almost covered the whole mitosis metaphase chromosomes and pachytene chromosomes of G.arboretum Shixiya 1 hybridized with gDNA probe,the euchromatin zone and heterochromatin zone were identified clearly on pachytene chromosomes,and the signals also look like non-continuous beads.Two BAC clones 150-D-24 and 182-F-9 in DNA BAC library of Pima90 were selected as probe to hybridize with mitosis metaphase chromosomes,pachytene chromosomes and DNA fiber of G.raimondii.

棉花FISH技术系统的应用研究。45S rDNA在亚洲棉石系亚1号中期和粗线期染色体上有两对大的信号，在DNA纤维上信号为非连续的念珠状，多个拷贝串联排列，每个拷贝长度大约在3～11μm，推测每个拷贝的实际长度为11～30kb；端粒序列在亚洲棉石系亚1号中期和粗线期染色体端部都有双点信号，在DNA纤维上信号也为非连续的念珠状，不同染色体上信号长度大约在1～9μm不等，推测实际长度为4～27kb；gDNA信号几乎布满整个亚洲棉石系亚1号中期和粗线期染色体，在粗线期染色体上能明显区分出常染色质区和异染色质区，DNA纤维上的信号均为非连续的念珠状。

Results MRI showed symmetric abnormal signals in basal ganglia in 27 patients, in thalami and dentate nucleus in 21 patients, and in corona radiata-centrum ovale in 9 patients. All the lesions were hyperintensity on T1WI. Local hypointensity in basal ganglia was found in 4 patients, while hyperintensity or slight hyperintensity on both T2WI and T2-FLAIR were found in 26 patients, and slight hyperintensity with hypointensity on both T2WI and T2-FLAIR in 1 patient.

结果 27例颅脑MRI表现为双侧基底节区片状对称性异常信号，21例双侧丘脑、齿状核片状异常信号，9例双侧放射冠－半卵圆中心见片状对称性异常信号；27例T1WI上见高信号区，其中4例基底节区病灶内见小片状低信号；26例T2WI及T2-FLAIR见高或稍高信号，1例见稍高、低混杂信号。

If you are unfortunate enough to the lovelorn, please tell me, I will help you out, really, please contact me!

如果你不幸失恋了，请告诉我，我会帮助你摆脱困境，真的，请联系我啦！

China's plan to cut energy intensity by 20 percent and pollutant discharges by 10 percent between 2006 and 2010 is a case in point.

中国计划在2006年到2010间降低20%的能源强度和减少10%的主要污染物排放，就是一个这样的例子。