查询词典 sampling location

Excepting the conventional methods of surveying samples, such as simple random sampling, stratified sampling, cluster sampling, systematic sampling, liner regression sampling, ratio estimator, two-stage sampling, double sampling, rotate sampling, non-probability sampling, there is sequential sampling and mark-recapture, particularly mark-recapture was introduced in detail.

针对生物资源的调查，除了一般抽样方法如：简单随机抽样、分层抽样、整群抽样、系统抽样、双重抽样、二阶抽样、样本轮换、比率估计、线性回归抽样和不等概抽样，还有序贯抽样和标记-重捕获方法，这里特别详细介绍了标记-重捕获方法。

Firstly,the sampling design has great impact on the accuracy of remote sensing classification.There exists great randomicity on the result of points and cluster sample verification on the different Sampling design.On the same sampling design,the stability of point sample verification is higher than that of Cluster sample verification.Secondly,the average accuracy of different sampling designs of multi-point and multi-cluster sample verification can reflect the accuracy characteristic.During the course of point sample verification,stratified sampling's error is lower than others'.During the course of cluster sample verification,systematic sampling and stratified sampling's accuracy are prior to simple random sampling's.

研究结果表明：（1）抽样方式对遥感分类精度评价结果的影响是客观存在的，不同抽样方式下的点样本和群样本检验结果都存在一定的随机性，但同一种抽样方式下，点样本检验精度评估结果的波动幅度小于群样本检验，稳定性比群样本检验要好；（2）不同抽样方式下的多次点样本和群样本检验的平均精度检验结果基本上都能够反映分类图像的精度特征，其中，点样本检验中，分层随机抽样点样本检验效果较好；群样本检验中，系统抽样群样本检验和分层随机抽样群样本检验的效果优于简单随机抽样群样本检验。

First, from the point of view of production and management, the importance for developing TTU is pointed out.the status in quo of technology,The direction of progress,The demand of practical and fundamentality in Distribution Automation are analyzed for Transformer Terminal Unit. The function of equipment and technical specification which meet demand of practical duty are indicated; Second, the scheme of synchronous sampling,quasi-synchronous sampling,non-integer cycle sampling,nonsynchronous sampling and algorithm are analyzed in detail. Then,the scheme of nonsynchronous sampling and multi-chunnel is ascertained. Moreover, the method of disposal sampling data for increasing precision which calculate the number of sampling per cycle dramatic by searching zero is introduced. The technique for analyzing data,stating data,storage data for Electrical Power Quality and control scheme for compensation capacitor are explained also. Finally, The scheme and structure of hardware,key circuitry using 80C196 singlechip,the scheme and ideology of software and flow chart of part software is introduced simply.

文中首先从电力生产、管理角度出发，指出了研制配变监测终端的重要意义，分析了配变监测终端的技术现状、发展趋势、现场需求以及在配网自动化中的基础地位，提出了满足实际运行要求的装置功能、技术要求；然后对目前常用的同步采样、准同步采样、非整周期采样、非同步采样的方案和算法进行了详细的分析、比较、筛选，确定了非同步采样和顺序采样的方案，并提出了一种寻找过零点从而动态计算每周采样点数的提高精度的采样数据处理方法，文中对装置中电能质量分析、统计、存储的方法以及补偿电容器的控制方案和投切原则也做了重点说明；最后，对应用80C196单片机系统研制的装置的硬件方案、结构以及关键电路和软件设计思路、方案、部分主要软件模块的流程图做了介绍。

In this review, historical background of sampling theory and development of forest inventories are presented. Application and research status of sampling methodology and technology in forest inventory in China and abroad are analyzed and reviewed, which includes sampling with probability proportional to frequency or to size, sampling based on remote sensing and sampling for rare population. Finally, both development trends and some problems of sampling methodology are discussed.

本文介绍了抽样理论的发展和国内外森林抽样调查发展过程，论述了森林调查中主要抽样方法的特点和研究现状，其中包括等概和不等概抽样、基于遥感的抽样、针对稀疏总体分布的抽样调查技术方法，并对这些抽样技术在国内外森林资源调查中的应用进行了综述，概括了抽样调查技术方法的发展趋势，最后总结了抽样技术方法还存在的一些问题。

Based on the design of deepsea microplankton concentrated and gas-tight sampler, the following sampling techniques are lucubrated: pollution-free sampling technique, pressure-jump-free sampling technique and in-situ concentrated sampling technique; deepsea highprecision gas-tight sampling technique; sealing technique of superpressure seawater hydraulic system; reliability design technique of deepsea high pressure cabin.

论文以深海浮游微生物浓缩保压取样器设计为背景，对深海无污染无压力突变原位浓缩取样技术、深海高精度保压取样技术、超高压海水液压系统密封设计技术和深海高压密封舱可靠性设计技术进行了深入研究。

At the same time, combining with the actual condition of delivery pipeline of our country and some prevalent leak detection and location methods, this paper raised a method, which is based on wavelet analysis and negative- pressure-wave to detect and locate the leakage. Jobs in the paper are as follows:As affected by gas density, pressure, specific heat and pipe material, the velocity of negative-pressure-wave improved depending on the energy conservation. At one time, taking the affection of velocity of gas flow, the location formula was modified in some degree.When locating the leaks with location formula, the iterative approach algorithm was adopted as a new method to increase the location accuracy level of system.Multi-scale decomposition and reconstruction of wavelet transform is utilized to filter the noise of negative-pressure-wave, which was brought by leakage. With the capacity to detect the signal singularity fast and accurately, wavelet transform was used to catch the break point of pressure signal. The work improved the accuracy of At in location formula, accordingly improved the location accuracy.Wavelet is a suitable tool for signal analysis. The distinct character is that the mother-wavelet is of optional. That means choosing different mother-wavelet will get different analysis result. So we studied how to choose mother-wavelet and its scale for signal singularity detection. The method is to choose a wavelet by regularities of the wavelet and the signal.Finally, a plan, which bases on SCADA system for inspection and detection of natural gas leakage, is proposed in the article.

其中，主要进行了以下几方面的工作：针对泄漏产生的负压波在管道中的传播速度受媒介的密度、压力、比热及材质等因素的影响，而非声波在空气中传播的速度，本文利用能量守恒原理，对其进行了修正；考虑到管内气体流速对压力波速的影响，对原始的负压波定位公式进行了一定程度的改进，并在利用定位公式进行泄漏点定位时采用逐步迭代逼近算法，提高了系统的定位精度；利用小波变换的多分辨率分解和重构技术，对采集到的管道发生泄漏时产生的负压波信号进行了降噪处理；并利用小波变换技术对信号奇异点的快速、准确的识别能力，对经上述消噪后的负压波信号进行了奇异点捕捉，精确捕捉的结果提高了定位公式中上下游站点采集到的负压波奇异点的时间差△t的精度，从而进一步提高了定位的精度；考虑到小波变换是一种基波可变的信号分析工具，也就是说，不同的小波基波对信号分析的结果将有很大差别，这势必影响最终的处理结果，因此，我们又对比分析了本课题中小波基及尺度的选择问题，依据规则性系数相似性原理对母小波的选择进行了探索性研究；最后，还提出了基于SCADA的泄漏检测与定位系统的软件开发构想及系统的嵌入方案。

node location is one of the key technologies in wireless sensor network.rssi－based location is a hotspot in nowadays.for resolving biggish error in rssi－based location,the paper presents a new method of location,rssi－based triangle and centroid location,using triangle and centroid method to reduce the error of rssi measurement.simulation experiments prove that this algorithm can obviously improve the location accuracy compared to trilateration.

摘 要：节点定位是无线传感器网络中的关键技术之一。基于rssi的定位技术是现阶段研究的热点，为解决rssi测量方法定位误差较大的问题，提出一种将rssi测量方法与三角形质心算法相结合的新型定位算法，该算法用三角形质心算法减小rssi的测量误差。仿真表明该算法比基于rssi的三边测量法定位算法的定位精度有较大提高。

The computer simulated sampling points with different grid cell sizes were generated and then interpolated into 10000 points with inverse distance weighted. Finally, the original value was compared with the interpolated value for the same grid cell to find the sampling error, and optimal sampling points were determined according to the allowable sampling error.

利用计算机按照不同的网格单元尺寸(如3×3，5×5，7×7等)进行采样，之后利用采样值进行IDW插值处理，将数据点恢复到原始的10000个，并把插值结果与原始值进行比较即可得到采样误差。

The frame lengths may be calculated from a greatest common divisor of a set of sampling rates providing watermarks which are robust against sampling rate conversions between any sampling rates of the set of sampling rates.

帧长度可以从提供水印的一组采样率的第一个公约数计算出来，它们对于这一组采样率中任意采样率之间的采样率转换而言是坚固的。

In this dissertation, digital lock-in detection techniques under integer period sampling and non-integer period sampling are separately investigated (1) Under integer period sampling, digital signal sequence is acquired through sampling the measured signal, but digital reference sequence is acquired through mathematical operation, then digital lock-in detection can be realized by calculating crosscorrelation function of digital signal sequence and digital reference sequence Harmonic measure is also analyzed, and a method of measuring harmonic of a periodic signal under aliasing is put forward.

本文对使用采样ADC把模拟信号转换为数字信号并通过计算数字信号的相关函数来实现锁定检测的技术进行了研究，在此基础上设计了一个多功能的数字LIA并在一些科学实验中进行了应用。本文对整周期采样和非整周期采样时的数字锁定检测技术分别进行了研究。(1)在整周期采样时，对被测信号进行采样得到信号序列，而参考序列由数学运算得到，通过计算信号序列和参考序列的互相关函数就可实现锁定检测。

A backer of an Afghan law that critics say legalizes marital rape has rejected the international outcry as foreign meddling.

饱受批评的一项法律的拥护者说合法化的婚内暴力不会受国际舆论的干涉。

Years ago, a ancient Egyptian fleet went to the Land of punt for seeking a kind of flavor named "myrrh", and aromatic plants which has dense exotic style for the queen Hatshepsut.

3500年前的一个古埃及的舰队到&彭特之地&寻找一种叫没药的香料。