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	黄海桑沟湾水体及沉积物中微塑料污染特征研究期刊论文 OAI收割海洋环境科学, 2019, 卷号: 38, 期号: 2, 页码: 198-204 作者: 熊宽旭; 赵新月; 周倩; 付传城; 涂晨 \| 收藏 \| 浏览/下载：40/0 \| 提交时间：2020/06/17 桑沟湾微塑料潮滩丰度空间分布 Sanggou bay microplastics tidal flats abundance spatial distribution In recent years,research on microplastics pollution in the marine environment has been increasing,but studies on microplastics in water bodies and sediments of the bay under the influence of high-intensity human activities are still rarely reported. In this study,the pollution characteristics of microplastics in the wayer and sediments of Sanggou bay were investigated in December 2017,after the harvest of large-scale aquaculture,with the aim to study the effects of aquaculture activities and hydrodynamics on pollution characteristics and spatial distribution of microplastics in the bay. The results showed that the types of microplastics in the water and sediments of Sanggou bay were mainly fibers,fragments,films,foams and particles. The microplastic abundances in the water and sediments were 1.8 ~ 31.2 N/L,31.2 ~ 1246.8 N/kg,respectively. The average particle sizes of microplastics in water and sediments were 0.51 0.20 mm and 1.54 1.02 mm,respectively. The results of spatial distribution of microplastics in Sanggou bay showed that the high abundance area mainly appears in the inshore waters,and the abundance of microplastics tends to decrease from the inner areas of estuary to the outshore areas. The heterogeneity of microplastic abundance and spatial distribution in Sanggou bay is mainly affected by human activities such as aquaculture,living and shipping,as well as hydrodynamics. In the future,fine sampling and analysis are needed to fully understand the temporal and spatial distribution of microplastics pollution in the bay areas.
	Boosted Near-miss Under-sampling on SVM ensembles for concept detection in large-scale imbalanced datasets 期刊论文 OAI收割 NEUROCOMPUTING, 2016, 卷号: 172, 页码: 198-206 作者: Bao, Lei; Juan, Cao; Li, Jintao; Zhang, Yongdong \| 收藏 \| 浏览/下载：29/0 \| 提交时间：2019/12/13 Concept learning Large-scale Imbalance Ensmeble learnning Support Vector Machine Boosted Near-miss Under-sampling
	A new digital backend in radio astronomy based on under-sampling technology 会议论文 OAI收割 5th International Conference on Machine Vision (ICMV) - Algorithms, Pattern Recognition and Basic Technologies, Wuhan, PEOPLES R CHINA, 2012-10-20 作者: Dong L(董亮); Wang M(汪敏); Bai, ZY; He, LS; Dong L(董亮) 收藏 \| 浏览/下载：23/0 \| 提交时间：2016/04/08 digital backend radio astronomy under-sampling technology ADCIntroduction
	Applications of digital if receivers and under-sampling technique in ladar 会议论文 OAI收割 international symposium on photoelectronic detection and imaging 2011: laser sensing and imaging; and biological and medical applications of photonics sensing and imaging, beijing, china, may 24, 2011 - may 26, 2013 SongZhi-Yuan; ZhuShao-Lan; DongLi-Jun; FengLi; HeHao-Dong 收藏 \| 浏览/下载：17/0 \| 提交时间：2012/07/09 Ladar Digital IF receiver Under-sampling Digital down-converter
	A high-accuracy parameter estimation algorithm for jointless Frequency-shift track circuit (EI CONFERENCE) 会议论文 OAI收割 ISECS International Colloquium on Computing, Communication, Control, and Management, CCCM 2008, August 3, 2008 - August 4, 2008, Guangzhou, China 作者: Zheng X. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 FSK (Frequency Shift keying) signal which has advantages of narrow-bandwidth strong anti-interference ability long transmission distance and so on is used in jointless Frequency-shift track circuit to send different kinds of control signals. However as FSK is non-linearly modulated parameter estimation with high accuracy is hard to realize. Based on the spectrum analysis complement with time-frequency distribution a highaccuracy FSK signal parameter estimation algorithm is put forward in this paper. According to the signal characteristics under-sampling and ZFFT are used to improve the accuracy of spectrum analysis and the base frequency resolution meets system requirement of 0.02Hz. Wigner-Ville distribution has an excellent time-frequency concentration while serious cross-term interference at the same time. Through the design of kernel function the cross-terms are almost suppressed and the upper/down side frequency resolution meets the system requirement of 0.2Hz. The effectivities of all the methods mentioned above have been proved by MATLAB simulation which pave a solid way for the development of high-accuracy FSK signal parameter estimation devices. 2008 IEEE.
	Abrupt sensor fault diagnosis based on wavelet network (EI CONFERENCE) 会议论文 OAI收割 2006 IEEE International Conference on Information Acquisition, ICIA 2006, August 20, 2006 - August 23, 2006, Weihai, Shandong, China 作者: Li W.; Li W.; Zhang H.; Zhang H. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 The possible faults of a sensor may be classified as abrupt (sudden) faults and incipient (slowly developing) faults. This paper focuses on the abrupt faults of a sensor. Due to the limited number of scales a single wavelet amplitude map has not enough scales to describe all details of the signal. The sampling grid in the scale direction is rather sparse Some of the fault information will be leaked under such sparse grid. To make up for the deficiency of scalar orthogonal wavelet transform in the application of abrupt fault diagnosis multiwavelet packets transform was introduced into the field of abrupt fault diagnosis. The distribution differences of the signal energy on decomposed multiwavelet scales of the signal before and after the fault occurring are extracted as the fault feature and used as the input of multi-dimensional wavelet network. A new model-free diagnostic method for isolating abrupt sensor faults is developed based on a proposed algorithm of multi-dimensional wavelet network constructing. The method has been proved to be quite effective in the detection of sensor abrupt fault. 2006 IEEE.