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Research on the Distribution of Network Nodes Based on Multiple Measurement Points
基于多点测量的网络节点度分布研究

LI Chao,ZHAO Hai,ZHANG Xin,GE Xin,
李超
,赵海,张昕,葛新

计算机科学 , 2008,
Abstract: Sampling bias caused by few points was first present,and by increasing the measurement points can reduce the omission of network edge.Based on the giant data samples authorized by CAIDA,the distribution of network nodes was analyzed respectively.The distribution of frequency-degree presents that the nodes of network follows power-law,and the distribution of network nodes exists heterogeneity confirmed by the degree-rank distribution.Cumulative function indicates that Weibull distribution may be more suitabl...
Red Shift Determination and Spectral Line Identification Based on Knowledge
基于知识的红移测量和谱线证认方法

Liu Rong,Duan Fu-qing,Liu San-yang,Wu Fu-chao,
刘 蓉
,段福庆,刘三阳,吴福朝

电子与信息学报 , 2006,
Abstract: A novel method for redshift determination and spectral line identification of celestial spectra is presented, which is based on the knowledge of feature spectral lines. Firstly, definition of redshift candidate and feature spectral line candidate is given, and the candidates are cross-validated according to the definition; Secondly, the density is estimated at every redshift candidate by using the Parzen window technique; Finally, the average of redshift candidates in Parzen window of the redshift candidate with maximum density is the redshift, and the feature spectral line candidates corresponding to those redshift candidates are feature spectral lines. Compared with other methods of the same kind, this method has a lower dependence on the quality of spectral line extraction. Experiments show that this method is robust and the correct rate is encouraging.
SENSOR OF OPTICAL WAVEGUIDE WITH LIQUID CORE FOR LIQUID DENSITY MEASUREMENT
液芯光波导溶液浓度传感器

Mat Yongxian,Zhou Zuoping,Fan Shiliang,
麦咏贤
,周佐平,范仕良

红外与毫米波学报 , 1995,
Abstract: A new system of large-diameter waveguide with liquid core for the measurement of liquid density is presented.The main advantage of this system is the relatively high measuring sensitivity. The principle of this system and the effect of construction parameters of the system on the sensitivity are discussed.The results of measurements are nearly in agreement with the theoretical analysis.
Chinese Internet router-level hop count measurement and analysis
中国Internet路由级跳数测量与分析*

MA Jian-guo,XI Ming-xian,LIN Yi-min,LI You-ping,
马建国
,席明贤,林益民,李幼平

计算机应用研究 , 2008,
Abstract: Measured sampled 6 754 active hosts at 7 measure sources with technology of distributed active measurement at the same time. The measurement returned 32 893 effective datas totally.After analyzing these datas,gave the Chinese Internet router-level hop count distribution and calculated the un-weighted average hop count was 14.938 89 and the weighted average hop count was 15.613 73.
The Methods of Water Spectra Measurement and Analysis Ⅰ:Above-Water Method
水体光谱测量与分析Ⅰ:水面以上测量法

TANG Jun-wu,TIAN Guo-liang,WANG Xiao-yong,WANG Xiao-mei,SONG Qing-jun,
唐军武
,田国良,汪小勇,王晓梅,宋庆君

遥感学报 , 2004,
Abstract: 水色遥感的基础之一是水体光谱特征测量与分析。水体光谱特性包括两个方面 :表观光学特性(AOPs)和固有光学特征 (IOPs)。该文主要讨论与水色遥感基本参数直接相关的表观光学量的测量与分析。现场表观光谱的测量从方法上可分为两类 :剖面测量法和水表面以上测量法。两种方法相对独立 ,适用范围上具有互补性。该文主要针对水面以上测量法进行讨论。水色遥感一般要求表观光谱特性的测量必须能够导出离水辐射率LW、归一化离水辐射率LWN、遥感反射率Rrs、和刚好处于水面以下 0 -深度的辐照度比R等。国际上有关水色的测量规范中 ,仅有针对大洋一类水体的。中国的近岸水体和湖水绝大部分是二类水体 ,因此该文也将对二类水体光谱测量的有关参数化问题进行讨论。同时 ,对数据分析处理中的一些关键参数的确定 ,提出新方法
Density Measurement of Liquid Metals Using Dilatometer
Lianwen WANG,Qingsong MEI,
Lianwen WANG and Qingsong MEI Shenyang National Laboratory for Materials Science
,Institute of Metal Research,Chinese Academy of Sciences,Shenyang,China

材料科学技术学报 , 2006,
Abstract: The dilatometer method for density measurement of liquid metals was improved to give a high measurement accuracy with simple operation. The density of liquid tin was measured and the results are in agreement with values in literature. The melting point density of liquid Sn was measured to be 6.966×103 Kg·m-3 and the temperature (T) dependence of the density (ρ) for liquid Sn can be well described by a polynomial equation ρ(T)=7.406 - 9.94 × 10-4T 2.12 × 10-7T2.
Damage Detection of Steel Bridge Based on Acceleration Power Spectral Density
加速度功率谱密度在钢桥损伤检测中的应用

LI Yue-bing,XING Shuang,Oshima T,
李曰兵
,邢爽,大岛俊之

实验力学 , 2009,
Abstract: Non-destructive testing of structure with the change of vibration characteristics attracted much attention in recent years. The basic idea of this method is that the vibration characteristics can reflect the state of the structure, and damages can cause changes of bridge vibration parameters. In order to study the method detecting steel bridge damages based on the power spectral density (PSD) of acceleration response, a disused railroad bridge in Japan was adopted as specimen, and six cases of damage were introduced to it in advance. The bridge was actuated by sinusoid sweeping frequency wave, and then the power spectral density differences between the undamaged and damaged bridge were analyzed. Experimental results show that the steel bridge damages can be detected and located by the changes of acceleration PSD.
Stochastic resonance in bistable duffing oscillators and its dynamical
双稳杜芬振子的随机共振及其动力学机制

Kang Yanmei Xu Jianxue Xie Yong,
康艳梅
,徐健学,谢勇

力学学报 , 2004,
Abstract: The method of moments is applied to the bistable Duffing oscillators driven by Gaussian white noise and weak periodic force,and the converging rate of the method is found dependent on the damping size,namely,with the same nonlinear parameter,it converges quicker if the damping coefficient is larger.Since the method of moments can make us disclose more general characteristic than only using numerical simulations,the results derived from the method of moments along with the numerical simulation results can make us to find relations between stochastic resonance and stochastic dynamical behavior.With the method of moments,the mono-peak and double-peak resonant structures in the system are disclosed with the spectral amplification factor for different drive frequencies for the case of the larger damping coefficient.To explain the derived resonant structure,the dependence of nonzero frequency peaks peaked out from fluctuating spectral density on noise intensity is investigated,and the double-peaked resonance is found to be resulted from the intrawell vibrations and the above potential barrier vibrations,which is a modification to the previous result.The study confirms there are three possible resonant sources,i.e.interwell jump,intrawell vibration and above-barrier vibration in the considered system,and the results have importance in statistical mechanics.
A New UWB Pulse Design Algorithm for Inband Interference Suppression
带内干扰抑制的超宽带脉冲设计

Guo Feng,Zhuang Yiqi,
郭锋
,庄奕琪

光子学报 , 2006,
Abstract: Using the combination of Gaussian monocycles pulse wi th different amplitude and different delay,a new ultra-wideband(UWB) pulse desi gn algorithm for Inband(narrowband or wideband) interference suppression is pres ented.With a Wireless Personal Area Network(WPAN) Communications short duration and a simple implement,the obtained UWB pulse not only meet Federal Communicatio ns Commission(FCC)spectral mask,but dramatically suppress the mutual interferenc es and successfully solves the coexistence problem between UWB system and others existing communication system.Compare with other pulse shapes,our pulse can car ry more energy.In the end,the communication performance of the UWB pulse in the paper and the optimal Gaussian-based monocycle is compared,our pulse have an ob vious advantage over the optimal Gaussian-based monocycle.
Study on Bright Band Detection Using Wind Profiler Radar
风廓线雷达探测零度层亮带的试验研究

HUANG Yu-,RUAN Zheng-,GE Run-sheng,CHEN Zhong-rong,
黄钰
,阮征,葛润生,陈钟荣

高原气象 , 2011,
Abstract: L-band wind profile is used in coherent accumulation technology to rise radar sounding sensitivity, vertical measurement precipitation cloud body is applied,which can obtain the entire spectrum information of cloud body return signal of high resolution.The wind profiler is used to continuously detect the bright band appeared in stratiform cloud precipitation process on May 14,2009.The variation and evolution characteristics of return signal spectrum parameter(power,average Doppler velocity,speed spectral wi...
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