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应用桑树叶片长宽信息估测叶面积 被引量:5
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作者 孙日彦 梁明芝 +3 位作者 杜建勋 王照红 官力民 王玺明 《蚕桑通报》 2002年第3期32-34,共3页
关键词 应用 桑树 叶片 信息估测 叶面积
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Non-destructive Evaluation of Absolute Stress in Steel Members Using Shear-Wave Spectroscopy
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作者 Liu Diankun He Jingbo +1 位作者 Li Zuohua Teng Jun 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第2期236-243,共8页
Non-destructive measurement of absolute stress in steel members can provide useful information to optimize the design of steel structures and allow the safety of existing structures to be evaluated.This paper investig... Non-destructive measurement of absolute stress in steel members can provide useful information to optimize the design of steel structures and allow the safety of existing structures to be evaluated.This paper investigates the non-destructive capability of ultrasonic shear-wave spectroscopy in absolute stress evaluation of steel members.The effect of steel-member stress on the shear-wave amplitude spectrum is investigated,and a method of absolute stress measurement is proposed.Specifically,the process for evaluating absolute stress using shear-wave spectroscopy is summarized.Two steel members are employed to investigate the relationship between the stress and the frequency in shear-wave echo amplitude spectrum.The H-beam loaded by the universal testing machine is evaluated by the proposed method and the traditional strain gauge method for verification.The results show that the proposed method is effective and accurate for determining absolute stress in steel members. 展开更多
关键词 absolute stress evaluation ultrasonic shear wave spectroscopy amplitude spectrum steel members non destructive testing method
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An Empirical Method for Estimating Background Stratospheric Aerosol Extinction Profiles over China 被引量:2
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作者 Yang Jing-Mei 《Atmospheric and Oceanic Science Letters》 2012年第2期95-101,共7页
The current paper introduces an empirical method for estimating the vertical distribution of background stratospheric aerosol extinction profiles covering the latitude bands of 50±5°N,40±5°N,30... The current paper introduces an empirical method for estimating the vertical distribution of background stratospheric aerosol extinction profiles covering the latitude bands of 50±5°N,40±5°N,30±5°N,and 20±5°N and the longitude range of 75 135°E based on Stratospheric Aerosol and Gas Experiment (SAGE) II aerosol extinction measurements at wavelengths of 1020 nm,525 nm,452 nm,and 386 nm for the volcanically calm years between 1998 2004.With this method,the vertical distribution of stratospheric aerosol extinction coefficients can be estimated according to latitude and wavelength.Comparisons of the empirically calculated aerosol extinction profiles and the SAGE II aerosol measurements show that the empirically calculated aerosol extinction coefficients are consistent with SAGE II values,with relative differences within 10% from 2 km above the tropopause to 33 km,and within 22% from 33 km to 35 km.The empirically calculated aerosol stratospheric optical depths (vertically integrated aerosol extinction coefficient) at the four wavelengths are also consistent with the corresponding SAGE II optical depth measurements,with differences within 2.2% in the altitude range from 2 km above the tropopause to 35 km. 展开更多
关键词 AEROSOL extinction coefficient STRATOSPHERE empirical method
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Real-time lane departure warning system based on principal component analysis of grayscale distribution and risk evaluation model 被引量:4
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作者 张伟伟 宋晓琳 张桂香 《Journal of Central South University》 SCIE EI CAS 2014年第4期1633-1642,共10页
A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and... A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and then each search bar was tracked using Kalman filter between frames. The lane detection performance was evaluated and demonstrated in ways of receiver operating characteristic, dice similarity coefficient and real-time performance. For lane departure detection, a lane departure risk evaluation model based on lasting time and frequency was effectively executed on the ARM-based platform. Experimental results indicate that the algorithm generates satisfactory lane detection results under different traffic and lighting conditions, and the proposed warning mechanism sends effective warning signals, avoiding most false warning. 展开更多
关键词 lane departure warning system lane detection lane tracking principal component analysis risk evaluation model ARM-based real-time system
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Evaluation and analysis on the tourism resources in Hami Region based on GIS mapping technology 被引量:1
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作者 FENG Xian-hua JU Chun-yan 《Ecological Economy》 2010年第4期457-462,共6页
According to the data from the national standard classification and investigation of tourism resources(GB/T 18972-2003) in Hami region,the abundance,quality and dimensional distribution of the tourism resources in Ham... According to the data from the national standard classification and investigation of tourism resources(GB/T 18972-2003) in Hami region,the abundance,quality and dimensional distribution of the tourism resources in Hami region were evaluated based on GIS mapping technology.The evaluation results on the tourism resources in Hami region are described as follows:there are rich tourism resources categories;the quality of tourism resources is ordinary;the resources distribute equably;the number of the historical resources is much more than the natural resources,but the 1atter still has great potential for developing.All the results of the evaluation can provide important references for strategic decision making of Hami region. 展开更多
关键词 Hami region evaluation of tourism resource GIS mapping technology
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Information Technology in Environmental Monitoring for Territorial System Ecological Assessment
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作者 Oleksandr Trofymchuk Dmytro Kreta +3 位作者 Mykyta Myrontsov Viacheslav Okhariev Viktor Shumeiko Snizhana Zagorodnia 《Journal of Environmental Science and Engineering(A)》 2015年第2期79-84,共6页
The environmental monitoring dataset of Rivne region territory (Ukraine) was analyzed using remote sensing technology and statistical analysis. The article reveals approaches to anthropogenic impact specificity asse... The environmental monitoring dataset of Rivne region territory (Ukraine) was analyzed using remote sensing technology and statistical analysis. The article reveals approaches to anthropogenic impact specificity assessment based on methods of correlation analysis. The information technology to assess soil quality based on satellite images decoding was created. 展开更多
关键词 Environmental safety anthropogenic impact environmental monitoring correlation analysis remote sensing.
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Distributed cubature Kalman filter based on observation bootstrap sampling
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作者 胡振涛 Hu Yumei +2 位作者 Zheng Shanshan Li Xian Guo Zhen 《High Technology Letters》 EI CAS 2016年第2期142-147,共6页
Aiming at the adverse effect caused by observation noise on system state estimation precision,a novel distributed cubature Kalman filter(CKF) based on observation bootstrap sampling is proposed.Firstly,combining with ... Aiming at the adverse effect caused by observation noise on system state estimation precision,a novel distributed cubature Kalman filter(CKF) based on observation bootstrap sampling is proposed.Firstly,combining with the extraction and utilization of the latest observation information and the prior statistical information from observation noise modeling,an observation bootstrap sampling strategy is designed.The objective is to deal with the adverse influence of observation uncertainty by increasing observations information.Secondly,the strategy is dynamically introduced into the cubature Kalman filter,and the distributed fusion framework of filtering realization is constructed.Better filtering precision is obtained by promoting observation reliability without increasing the hardware cost of observation system.Theory analysis and simulation results show the proposed algorithm feasibility and effectiveness. 展开更多
关键词 state estimation cubature Kalman filter (CKF) observation bootstrap sampling distributed weighted fusion
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A Model-calibration Approach to Using Complete Auxiliary Information from Stratified Sampling Survey Data
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作者 WU Chang-chun ZHANG Run-chu 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第2期309-316,共8页
In stratified survey sampling, sometimes we have complete auxiliary information. One of the fundamental questions is how to effectively use the complete auxiliary information at the estimation stage. In this paper, we... In stratified survey sampling, sometimes we have complete auxiliary information. One of the fundamental questions is how to effectively use the complete auxiliary information at the estimation stage. In this paper, we extend the model-calibration method to obtain estimators of the finite population mean by using complete auxiliary information from stratified sampling survey data. We show that the resulting estimators effectively use auxiliary information at the estimation stage and possess a number of attractive features such as asymptotically design-unbiased irrespective of the working model and approximately model-unbiased under the model. When a linear working-model is used, the resulting estimators reduce to the usual calibration estimator(or GREG). 展开更多
关键词 model-calibration pseudo empirical likelihood stratified sampling survey complete auxiliary information estimating equations generalized linear models superpopulation
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INFORMATION FUSION STEADY-STATE WHITE NOISE DECONVOLUTION ESTIMATORS WITH TIME-DELAYED MEASUREMENTS AND COLORED MEASUREMENT NOISES
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作者 Sun Xiaojun Deng Zili 《Journal of Electronics(China)》 2009年第2期161-167,共7页
White noise deconvolution or input white noise estimation problem has important appli-cation backgrounds in oil seismic exploration,communication and signal processing.By the modern time series analysis method,based o... White noise deconvolution or input white noise estimation problem has important appli-cation backgrounds in oil seismic exploration,communication and signal processing.By the modern time series analysis method,based on the Auto-Regressive Moving Average(ARMA) innovation model,under the linear minimum variance optimal fusion rules,three optimal weighted fusion white noise deconvolution estimators are presented for the multisensor systems with time-delayed measurements and colored measurement noises.They can handle the input white noise fused filtering,prediction and smoothing problems.The accuracy of the fusers is higher than that of each local white noise estimator.In order to compute the optimal weights,the formula of computing the local estimation error cross-covariances is given.A Monte Carlo simulation example for the system with 3 sensors and the Bernoulli-Gaussian input white noise shows their effectiveness and performances. 展开更多
关键词 Multisensor information fusion White noise estimator DECONVOLUTION Time-delayed measurement Modern time series analysis method
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Evaluating information-seeking approaches to metacognition
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作者 Jonathon D. CRYSTAL Allison L. FOOTE 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第4期531-542,共12页
Metacognition has been divided into information monitoring and control processes. Monitoring involves knowing that you know or do not know some information without taking corrective action. Control involves taking cor... Metacognition has been divided into information monitoring and control processes. Monitoring involves knowing that you know or do not know some information without taking corrective action. Control involves taking corrective action based on the knowledge that you know or do not know some information. In comparative metacognition, considerable attention has been paid toward critically assessing putative evidence for information monitoring in non-human animals. However, less attention has been paid toward critically evaluating evidence for control processes in animals. We briefly review a critique of information-monitoring in animals. Next, we apply these concepts to a number of studies that focus on information seeking in animals. The main type of evidence for control processes in animals come from tube tipping experiments. Before having the opportunity to search for the bait in these experiments, the subject sometimes observes opaque tubes being baited but is sometimes prevented from seeing the baiting. The observations that the subjects look more if baiting was not seen and are more accurate if baiting was seen have been taken as evidence for metacognition in information-seeking experiments. We propose simple alternative hypotheses that are sufficient to explain putative evidence for information seeking in animals without positing metacognition. The alternative explanation focuses on two relatively simple principles: First, an animal has a default "look before you go" response which supersedes random searches in space. Second, spatially guided behavior follows a default rule of "go where something good is." These principles can explain the results of tube tipping experiments without proposing metacognition [Current Zoology 57 (4): 531-542, 2011]. 展开更多
关键词 METACOGNITION Metacognitive control Information seeking Metacognitive monitoring Information monitoring Comparative cognition
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