中国科学院机构知识库网格系统: 检索

Text-mining-based Fake News Detection Using Ensemble Methods 期刊论文 OAI收割
International Journal of Automation and Computing, 2020, 卷号: 17, 期号: 2, 页码: 210-221
作者: Harita Reddy; Namratha Raj; Manali Gala; Annappa Basava

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收藏 | 浏览/下载：20/0 | 提交时间：2021/02/22

Fake news social media stylometric features word vectors ensemble methods.

Comparison of Ozone Fluxes over a Maize Field Measured with Gradient Methods and the Eddy Covariance Technique 期刊论文 OAI收割
大气科学进展:英文版, 2020, 卷号: 37.0, 期号: 006, 页码: 586
作者: Zhilin ZHU; Xinzhai TANG; Fenghua ZHAO

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收藏 | 浏览/下载：21/0 | 提交时间：2021/03/16

methods. Ozone coefficient

Comparison of Ozone Fluxes over a Maize Field Measured with Gradient Methods and the Eddy Covariance Technique 期刊论文 OAI收割
大气科学进展:英文版, 2020, 卷号: 37.0, 期号: 006, 页码: 586
作者: Zhilin ZHU; Xinzhai TANG; Fenghua ZHAO

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收藏 | 浏览/下载：21/0 | 提交时间：2021/03/16

methods. Ozone coefficient

Evaluation of spatial upscaling methods based on remote sensing data with multiple spatial resolutions (EI CONFERENCE) 会议论文 OAI收割
Satellite Data Compression, Communications, and Processing VIII, August 12, 2012 - August 13, 2012, San Diego, CA, United states
Ren R.; Gu L.; Cao J.; Chen H.; Sun J.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

In most applications of remote sensing data special spatial information is required from a finer to a coarser spatial resolution with appropriate upscaling methods. The purpose of this paper is to compare and evaluate current spatial upscaling methods using MODIS remote sensing data with multiple spatial resolutions. In the research Northeast China was selected as the study area. MODIS data with spatial resolutions of 250 m (2 bands) and 500 m (7 bands) were used as the test data. Through using the selected upscaling methods the Band 1 and Band 2 data of MODIS were scaled up from 250 m to 500 m spatial resolution. On the basis of land cover characteristics of Northeast China the MODIS data located in the study area was classified into the five land cover types including water grasslands forests farmlands and bare lands using maximum likelihood method. The land cover classification results were further compared with MODIS Land Cover Type product. Finally Structural Similarity (SSIM) was selected to evaluate the effects of these upscaling methods. The research can provide more useful information for spatial scaling transformation in remote sensing data applications. 2012 SPIE.

The design of computer-generated holograms for testing unsymmetrical optical surfaces (EI CONFERENCE) 会议论文 OAI收割
2012 International Symposium on Photonics and Optoelectronics, SOPO 2012, May 21, 2012 - May 23, 2012, Shanghai, China
作者: Zhang X.; Zhang Y.; Zhang X.; Zhang X.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

It is a technical difficulty to test the unsymmtrical optical surfaces in non-contact methods. But we can do it using computer-generated holograms (CGH). The principle and design of the CGH have been discussed in the paper. Take the cubic suface as an example The order separation of the CGH is analyzed theoretically and the simulation result of the order separation is given in the paper. We develop the binary process of the continuous CGH phase function and get the sample of the amplitude CGH. A CGH for testing a cubic phase plate with duty cycle 0.5 is fabricated by using e-beam lithographic techniques. In this situation the contrast of the interference fringe pattern can achieve a level of 99.4% by calculation. 2012 IEEE.

Structure buckling load interval analysis of supercavitating projectile (EI CONFERENCE) 会议论文 OAI收割
2011 9th International Conference on Reliability, Maintainability and Safety: Safety First, Reliability Primary, ICRMS'2011, June 12, 2011 - June 15, 2011, Guiyang, China
作者: Zhou L.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

As a result of supercavitating projectiles with high underwater velocity their structures undergo high longitudinal force. It is necessary to perform structure buckling load interval analysis because the uncertainty of structural own parameters should be considered. Critical buckling load of supercavitating projectiles is calculated by Galerkin method. The partial matrixes of critical buckling load implicit function to each uncertainty variable are deduced and the interval of structure critical buckling load is calculated by interval analysis and convex model methods. Numerical results show that the nominal value lower and upper bounds of critical buckling load increase with the increment of the ratio of base diameter to cavitator diameter. And the uncertainty degree of basic variables should be controlled as far as possible in the project for high reliability. 2011 IEEE.

The research on adaptive measurement of angular acceleration for photoelectric servo turntable (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China
作者: Guo J.; Chen J.; Guo J.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

The paper proposes a new measurement method of angular acceleration for photoelectric servo turntable. Piezoelectric angular acceleration sensor is used to measure angular acceleration directly Adaptive FIR filter based on LMS algorithm is established on DSP by which angular acceleration signal can be filtered and corrected errors adaptively then angular acceleration signals can be measured adaptively. This method avoids measurement errors and calculation noise by computing angular acceleration indirectly thus improving measurement precision and making measurement results better than traditional methods. The gotten angular acceleration can be sent to servo control mechanism as feed forward control signals to improve control effects of servo turntable significantly. 2011 IEEE.

Realization of auto-focusing system for cameras based on TMS320F2812 DSP (EI CONFERENCE) 会议论文 OAI收割
2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China
作者: Zhang T.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

Focusing systems play an important role in a variety of optical measurements and detection instruments. In this paper several kinds of auto-focusing methods were described and the relevant focusing evaluation functions were introduced based on image processing methods. An auto-focusing system based on image processing was designed by using the TMS320F2812 digital signal processing chip as a platform. Moreover some problem and solutions about auto-focusing system was demonstrated. The system designed in this paper can find the good image plane in 10 steps (about 5 second) thus it can meet the requirements of practical applications. 2011 IEEE.

Local variance based color image quality assessment method (EI CONFERENCE) 会议论文 OAI收割
2011 2nd International Conference on Advanced Measurement and Test, AMT 2011, June 24, 2011 - June 26, 2011, Nanchang, China
作者: Wang Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

In this paper local variance is used to describe the structural information of a color image in order to assess its quality. The representation method is different from conventional models in that some information that is sensitive to human eyes is enhanced by using local variance distribution. It encodes the local variance distribution of different channels of a color image into the three imaginary parts of a quaternion. The distance between the singular value feature vectors of the source image block and the distorted image block which are described by quaternion matrices is calculated. The experimental results show that the assessment results of the proposed assessment method are more consistent with the Human Visual System than those of the conventional assessment methods.

CCD performance model and noise control (EI CONFERENCE) 会议论文 OAI收割
3rd International Conference on Image Analysis and Signal Processing, IASP 2011, October 21, 2011 - October 23, 2011, Wuhan, China
作者: Sun H.; Wang Z.; Wang Z.; Sun H.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

In this paper we describe the performance models of a Charge Coupling Device (CCD) and discuss the issues in the CCD image sensor that deteriorates the CCD imaging performance. We analyze the cause of noise in the CCD imaging sensor and provide methods to control the CCD noise to improve the CCD's imaging quality. Some simulation results are presented in the paper to show the efficiency of the noise control methods. 2011 IEEE.