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A Multi-Stage Pipeline for Date Fruit Processing: Integrating YOLOv11 Detection, Classification, and Automated Counting
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作者 Ali S.Alzaharani Abid Iqbal 《Computers, Materials & Continua》 2026年第1期1327-1353,共27页
In this study,an automated multimodal system for detecting,classifying,and dating fruit was developed using a two-stage YOLOv11 pipeline.In the first stage,the YOLOv11 detection model locates individual date fruits in... In this study,an automated multimodal system for detecting,classifying,and dating fruit was developed using a two-stage YOLOv11 pipeline.In the first stage,the YOLOv11 detection model locates individual date fruits in real time by drawing bounding boxes around them.These bounding boxes are subsequently passed to a YOLOv11 classification model,which analyzes cropped images and assigns class labels.An additional counting module automatically tallies the detected fruits,offering a near-instantaneous estimation of quantity.The experimental results suggest high precision and recall for detection,high classification accuracy(across 15 classes),and near-perfect counting in real time.This paper presents a multi-stage pipeline for date fruit detection,classification,and automated counting,employing YOLOv11-based models to achieve high accuracy while maintaining real-time throughput.The results demonstrated that the detection precision exceeded 90%,the classification accuracy approached 92%,and the counting module correlated closely with the manual tallies.These findings confirm the potential of reducing manual labour and enhancing operational efficiency in post-harvesting processes.Future studies will include dataset expansion,user-centric interfaces,and integration with harvesting robotics. 展开更多
关键词 Date fruit cultivation YOLOv11 precision agriculture real-time processing automated fruit counting deep learning agricultural productivity
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HUANNet: A High-Resolution Unified Attention Network for Accurate Counting
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作者 Haixia Wang Huan Zhang +2 位作者 Xiuling Wang Xule Xin Zhiguo Zhang 《Computers, Materials & Continua》 2026年第1期1722-1741,共20页
Accurately counting dense objects in complex and diverse backgrounds is a significant challenge in computer vision,with applications ranging from crowd counting to various other object counting tasks.To address this,w... Accurately counting dense objects in complex and diverse backgrounds is a significant challenge in computer vision,with applications ranging from crowd counting to various other object counting tasks.To address this,we propose HUANNet(High-Resolution Unified Attention Network),a convolutional neural network designed to capture both local features and rich semantic information through a high-resolution representation learning framework,while optimizing computational distribution across parallel branches.HUANNet introduces three core modules:the High-Resolution Attention Module(HRAM),which enhances feature extraction by optimizing multiresolution feature fusion;the Unified Multi-Scale Attention Module(UMAM),which integrates spatial,channel,and convolutional kernel information through an attention mechanism applied across multiple levels of the network;and the Grid-Assisted Point Matching Module(GPMM),which stabilizes and improves point-to-point matching by leveraging grid-based mechanisms.Extensive experiments show that HUANNet achieves competitive results on the ShanghaiTech Part A/B crowd counting datasets and sets new state-of-the-art performance on dense object counting datasets such as CARPK and XRAY-IECCD,demonstrating the effectiveness and versatility of HUANNet. 展开更多
关键词 Accurate counting high-resolution representations point-to-point matching
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eDNA enhances detection efficiency but reveals lower waterbird diversity:A comparison with point counting method
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作者 Hongming Shuai Xiaoru Liu +3 位作者 Yigui Zhang Yuqi Sun Hao Li Zhongqiu Li 《Avian Research》 2025年第2期221-229,共9页
Environmental DNA(e DNA)methods have emerged as a promising tool for studying a broad spectrum of biological taxa.However,metabarcoding studies of avian biodiversity using e DNA have received little attention.In this ... Environmental DNA(e DNA)methods have emerged as a promising tool for studying a broad spectrum of biological taxa.However,metabarcoding studies of avian biodiversity using e DNA have received little attention.In this study,we compared waterbird biodiversity derived from e DNA metabarcoding with that obtained from traditional point counting surveys at 23 sites in Tai Lake of eastern China and evaluated the accuracy of e DNA metabarcoding for waterbird community studies.The point counting method recorded a higher total number of waterbird species(22)compared to the e DNA technique(16).While e DNA achieved a 74.5%detection rate for waterbird species and was able to identify a significantly greater number of species(12.48±1.97)at each sampling site than point counting method(6.13±2.69),particularly highlighting several rare and elusive species,it failed to detect some species commonly observed by the point counting method.The alpha diversity analysis revealed no significant differences in waterbird diversity between the e DNA method and the point counting method,except that the e DNA method exhibited lower Pielou evenness.Waterbird e DNA sequencing abundance correlated significantly with species occurrence,whereas Spearman's analysis indicated no significant difference between e DNA sequence abundance and species abundance from the point counting method.e DNA method detected no significant difference in waterbird composition between sampling sites,while the point counting method revealed significant differences.Consequently,e DNA is an effective complementary tool for assessing the diversity of wintering waterbirds in lakes,though it is unable to capture the full diversity of waterbird communities.It is crucial to develop sampling strategies that comprehensively monitor species composition and integrate e DNA with traditional survey methods for accurate evaluation of community structure. 展开更多
关键词 Environmental DNA Metabarcoding Point counting Species abundance Tai lake Waterbird diversity
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Delayed covering causes the accumulation of motile sperm, leading to overestimation of sperm concentration and motility with a Makler counting chamber
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作者 Lin Yu Qing-Yuan Cheng +4 位作者 Ye-Lin Jia Yan Zheng Ting-Ting Yang Ying-Bi Wu Fu-Ping Li 《Asian Journal of Andrology》 2025年第1期59-64,共6页
According to the World Health Organization(WHO)manual,sperm concentration should be measured using an improved Neubauer hemocytometer,while sperm motility should be measured by manual assessment.However,in China,thous... According to the World Health Organization(WHO)manual,sperm concentration should be measured using an improved Neubauer hemocytometer,while sperm motility should be measured by manual assessment.However,in China,thousands of laboratories do not use the improved Neubauer hemocytometer or method;instead,the Makler counting chamber is one of the most widely used chambers.To study sources of error that could impact the measurement of the apparent concentration and motility of sperm using the Makler counting chamber and to verify its accuracy for clinical application,67 semen samples from patients attending the Department of Andrology,West China Second University Hospital,Sichuan University(Chengdu,China)between 13 September 2023 and 27 September 2023,were included.Compared with applying the cover glass immediately,delaying the application of the cover glass for 5 s,10 s,and 30 s resulted in average increases in the sperm concentration of 30.3%,74.1%,and 107.5%,respectively(all P<0.0001)and in the progressive motility(PR)of 17.7%,30.8%,and 39.6%,respectively(all P<0.0001).However,when the semen specimens were fixed with formaldehyde,a delay in the application of the cover glass for 5 s,10 s,and 30 s resulted in an average increase in the sperm concentration of 6.7%,10.8%,and 14.6%,respectively,compared with immediate application of the cover glass.The accumulation of motile sperm due to delays in the application of the cover glass is a significant source of error with the Makler counting chamber and should be avoided. 展开更多
关键词 concentration improved Neubauer hemocytometer Makler counting chamber MOTILITY SPERM
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Commentary on“Delayed covering causes the accumulation of motile sperm,leading to overestimation of sperm concentration and motility with a Makler counting chamber”
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作者 Elisabetta Tosti 《Asian Journal of Andrology》 2025年第1期135-136,共2页
The analysis of the ejaculate,better known as spermiogram,represents the first and main step to identify whether a series of sperm quality parameters are within the norm and therefore are consistent with normal sperm ... The analysis of the ejaculate,better known as spermiogram,represents the first and main step to identify whether a series of sperm quality parameters are within the norm and therefore are consistent with normal sperm fertilizing capacity.Among these,sperm concentration and motility are the first parameters to be evaluated through an estimation carried out by expert examiners. 展开更多
关键词 identify whether series sperm quality parameters within delayed covering accumulation MOTILITY OVERESTIMATION makler counting chamber motile sperm sperm concentration
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Accurate counting of RNA in tissues with highly denoising amplified imaging
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作者 Xiaowen Cao Yuheng Zhu +2 位作者 Siyue Fan Feng Chen Yongxi Zhao 《Chinese Chemical Letters》 2025年第12期463-466,共4页
Characterization of the distribution and accurate counting of RNA molecules in the context of tissues is necessary to understand their complexity and heterogeneity.Single-molecule fluorescence in situ hybridization re... Characterization of the distribution and accurate counting of RNA molecules in the context of tissues is necessary to understand their complexity and heterogeneity.Single-molecule fluorescence in situ hybridization reveals the abundance and distribution of RNA and resolves different cell types in complex tissues.Especially,off-target binding and nonspecific adsorption of probes are prone to producing nonspecific amplification.Herein,we present highly de-noising amplified imaging,which leverages a sitespecific cleavage-amplifying design to achieve accurate counting of RNA in tissues.Our method avoids adding probe as primer,decreases nonspecific spots of single cells from 7 to nearly zero,and enables RNA imaging in uncleared tissue sections with nearly zero noise.We demonstrate the efficacy of this method on various thickness of mouse tissue sections.We envision this approach will serve as a tool to revealing the information content from patient samples for biomedical purpose. 展开更多
关键词 Nucleic acid amplification RNA endonuclease RNA counting Single-cell imaging Tissue sections
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A Method for Small Target Detection and Counting of the End of Drill Pipes Based on the Improved YOLO11n
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作者 Miao Li Xiaojun Li Mingyang Zhao 《Computers, Materials & Continua》 2025年第10期1917-1936,共20页
Aiming at problems such as large errors and low efficiency in manual counting of drill pipes during drilling depth measurement,an intelligent detection and counting method for the small targets at the end of drill pip... Aiming at problems such as large errors and low efficiency in manual counting of drill pipes during drilling depth measurement,an intelligent detection and counting method for the small targets at the end of drill pipes based on the improved YOLO11n is proposed.This method realizes the high-precision detection of targets at drill pipe ends in the image by optimizing the target detection model,and combines a post-processing correction mechanism to improve the drill pipe counting accuracy.In order to alleviate the low-precision problem of YOLO11n algorithm for small target recognition in the complex underground background,the YOLO11n algorithm is improved.First,the key module C3k2 in the backbone network was improved,and Poly Kernel Inception(PKI)Block was introduced to replace Bottleneck in it to fully integrate the target context information and the model’s capability of feature extraction;Second,within the model’s neck network,a new feature fusion pyramid ISOP(Improved Small Object Pyramid)is proposed,SPDConv is introduced to strengthen the P2 feature,and CSP and OmniKernel are combined to integrate multi-scale features;Finally,the default loss function is substituted with Powerful-IoU(PIoU)to solve the anchor box expansion problem.On the self-built dataset,experimental verification was conducted.The findings showed that the Recall rose by 6.4%,mAP@0.5 increased by 4.5%,and mAP@0.5:0.95 improved by 6%compared with the baseline model,effectively solving the issues of false detection and missed detection problems in small target detection task.Meanwhile,we conducted counting tests on drilling videos from 5 different scenarios,achieving an average accuracy of 97.3%,which meets the accuracy needs for drill pipe recognition and counting in coal mine drilling sites.The research findings offer theoretical basis and technical backing for promoting the intelligent development of coal mine gas extraction drilling sites. 展开更多
关键词 YOLO11n drill pipe counting small target PKI Block PIoU loss function
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Cluster counting algorithm for the CEPC drift chamber using LSTM and DGCNN
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作者 Zhe-Fei Tian Guang Zhao +7 位作者 Ling-Hui Wu Zhen-Yu Zhang Xiang Zhou Shui-Ting Xin Shuai-Yi Liu Gang Li Ming-Yi Dong Sheng-Sen Sun 《Nuclear Science and Techniques》 2025年第7期14-23,共10页
The particle identification(PID)of hadrons plays a crucial role in particle physics experiments,especially in flavor physics and jet tagging.The cluster counting method,which measures the number of primary ionizations... The particle identification(PID)of hadrons plays a crucial role in particle physics experiments,especially in flavor physics and jet tagging.The cluster counting method,which measures the number of primary ionizations in gaseous detectors,is a promising breakthrough in PID.However,developing an effective reconstruction algorithm for cluster counting remains challenging.To address this challenge,we propose a cluster counting algorithm based on long short-term memory and dynamic graph convolutional neural networks for the CEPC drift chamber.Experiments on Monte Carlo simulated samples demonstrate that our machine learning-based algorithm surpasses traditional methods.It improves the K/πseparation of PID by 10%,meeting the PID requirements of CEPC. 展开更多
关键词 Particle identification Cluster counting Machine learning Drift chamber
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GENERALIZED COUNTING FUNCTIONS AND COMPOSITION OPERATORS ON WEIGHTED BERGMAN SPACES OF DIRICHLET SERIES
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作者 Min HE Maofa WANG Jiale CHEN 《Acta Mathematica Scientia》 2025年第2期291-309,共19页
In this paper,we study composition operators on weighted Bergman spaces of Dirichlet series.We first establish some Littlewood-type inequalities for generalized mean counting functions.Then we give sufficient conditio... In this paper,we study composition operators on weighted Bergman spaces of Dirichlet series.We first establish some Littlewood-type inequalities for generalized mean counting functions.Then we give sufficient conditions for a composition operator with zero characteristic to be bounded or compact on weighted Bergman spaces of Dirichlet series.The corresponding sufficient condition for compactness in the case of positive characteristics is also obtained. 展开更多
关键词 generalized counting function Dirichlet series composition operator weighted Bergman space
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Dynamic regional population counting and localization method based on high resolution fusion
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作者 ZHANG Jiaojiao CHEN Yong 《Journal of Measurement Science and Instrumentation》 2025年第4期515-525,共11页
Aiming at the problem of inaccurate crowd counting and location in dense scenes,a dynamic region-sensing crowd counting and location method based on high-resolution fusion was proposed.Firstly,U-HRNet was used as the ... Aiming at the problem of inaccurate crowd counting and location in dense scenes,a dynamic region-sensing crowd counting and location method based on high-resolution fusion was proposed.Firstly,U-HRNet was used as the main backbone to extract highresolution features of the population and enhance the ability of feature extraction with different resolutions.Then,the dynamic regional awareness attention module was designed to make full use of the global and local feature information,refine the differentiated learning of target feature and background feature,reduce the interference of background feature,and improve the positioning performance of the model.Finally,the predicted threshold map and confidence map were input into the binarization module to output the prediction and counting results of the crowd independent individual target.Experimental results showed that the proposed method achieved good performance of counting and positioning in different scenarios. 展开更多
关键词 deep learning dense crowd count high-resolution fusion dynamic regional awareness crowd location
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Preparation of the Ag_2O_2-PbO_2 Modified Electrode and Its Application towards Escherichia coli Fast Counting in Water 被引量:3
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作者 JingGU WenZHANG +3 位作者 YuFengYANG LeiZHENG ZiRongWU LiTongJIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第5期635-638,共4页
A novel nano crystalline Ag2O2-PbO2 film chemically modified electrode (CME) was prepared and the CME was characterized by X-ray diffractometer (XRD) and atomic force microscope (AFM). By chronoamperometry, the nano A... A novel nano crystalline Ag2O2-PbO2 film chemically modified electrode (CME) was prepared and the CME was characterized by X-ray diffractometer (XRD) and atomic force microscope (AFM). By chronoamperometry, the nano Ag2O2-PbO2 CME was used as bioelectro- chemical sensor to determine the population of Escherichia coli (E. coli) in water. Compared with conventional methods, it is found that the technique we used is fast and convenient in counting E. coli. 展开更多
关键词 Ag2O2-PbO2 modified platinum electrode Escherichia coli fast counting.
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基于Counting Bloom Filter的海量网页快速去重研究
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作者 刘年国 王芬 +2 位作者 吴家奇 李雪 陶涛 《安徽电气工程职业技术学院学报》 2016年第3期92-97,共6页
网页去重是从给定的大量的数据集合中检测出冗余的网页,然后将冗余的网页从该数据集合中去除的过程,其中基于同源网页的URL去重的研究已经取得了很大的发展,但是针对海量网页去重问题,目前还没有很好的解决方案,文章在基于MD5指纹库网... 网页去重是从给定的大量的数据集合中检测出冗余的网页,然后将冗余的网页从该数据集合中去除的过程,其中基于同源网页的URL去重的研究已经取得了很大的发展,但是针对海量网页去重问题,目前还没有很好的解决方案,文章在基于MD5指纹库网页去重算法的基础上,结合Counting Bloom Filter算法的特性,提出了一种快速去重算法IMP-CBFilter。该算法通过减少I/O频繁操作,来提高海量网页去重的效率。实验表明,IMP-CBFilter算法的有效性。 展开更多
关键词 网页去重 MD5指纹库 counting BLOOM Filter IMP-CBFilter算法
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VitSeg-Det&Trans Tra-Count:Networks for Robust Crack Detection and Measurement in Dynamic Video Scenes
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作者 Langyue Zhao Yubin Yuan Yiquan Wu 《Computers, Materials & Continua》 2026年第4期1965-1995,共31页
Regular detection of pavement cracks is essential for infrastructure maintenance.However,existing methods often ignore the challenges such as the continuous evolution of crack features between video frames and the dif... Regular detection of pavement cracks is essential for infrastructure maintenance.However,existing methods often ignore the challenges such as the continuous evolution of crack features between video frames and the difficulty of defect quantification.To this end,this paper proposes an integrated framework for pavement crack detection,segmentation,tracking and counting based on Transformer.Firstly,we design theVitSeg-Det network,which is an integrated detection and segmentation network that can accurately locate and segment tiny cracks in complex scenes.Second,the TransTra-Count system is developed to automatically count the number of defects by combining defect tracking with width estimation.Finally,we conduct experimental verification on three datasets.The results show that the proposed method is superior to the existing deep learning methods in detection accuracy.In addition,the actual scene video test shows that the framework can accurately label the defect location and output the number of defects in real time. 展开更多
关键词 Crack detection multi object tracking semantic segmentation counting transformer
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营养状态与心血管疾病关系的研究进展
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作者 赵鹏飞 《临床医学进展》 2026年第1期2236-2245,共10页
营养不良与多种疾病的不良预后相关,近些年在心血管疾病中也有许多研究发现营养不良与心血管疾病预后相关,但目前心血管疾病并无公认的营养不良金标准,本文梳理了营养不良与心血管疾病之间的关系,并且探讨了多种营养不良评估工具目前在... 营养不良与多种疾病的不良预后相关,近些年在心血管疾病中也有许多研究发现营养不良与心血管疾病预后相关,但目前心血管疾病并无公认的营养不良金标准,本文梳理了营养不良与心血管疾病之间的关系,并且探讨了多种营养不良评估工具目前在心血管疾病关系的研究,特别是客观营养状态评分工具COUNT、GNRI及PNI评估为营养不良的患者在多种心血管疾病预后不佳,同时部分营养状态评分意义仍有争议。 展开更多
关键词 营养状态 COUNT GNRI PNI 心血管疾病 研究进展
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A deep-junction single-photon detector with field polysilicon gate structure for increased photon detection efficiency and reduced dark count noise
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作者 Zhentao Ni Dajing Bian +2 位作者 Haoxiang Jiang Xiaoming Huang Yue Xu 《Journal of Semiconductors》 2026年第1期65-71,共7页
A high-sensitivity,low-noise single photon avalanche diode(SPAD)detector was presented based on a 180 nm BCD process.The proposed device utilizes a p-implant layer/high-voltage n-well(HVNW)junction to form a deep aval... A high-sensitivity,low-noise single photon avalanche diode(SPAD)detector was presented based on a 180 nm BCD process.The proposed device utilizes a p-implant layer/high-voltage n-well(HVNW)junction to form a deep avalanche multiplication region for near-infrared(NIR)sensitivity enhancement.By optimizing the device size and electric field of the guard ring,the fill factor(FF)is significantly improved,further increasing photon detection efficiency(PDE).To solve the dark noise caused by the increasing active diameter,a field polysilicon gate structure connected to the p+anode was investigated,effectively suppressing dark count noise by 76.6%.It is experimentally shown that when the active diameter increases from 5 to 10μm,the FF is significantly improved from 20.7%to 39.1%,and thus the peak PDE also rises from 13.3%to 25.8%.At an excess bias voltage of 5 V,a NIR photon detection probability(PDP)of 6.8%at 905 nm,a dark count rate(DCR)of 2.12 cps/μm^(2),an afterpulsing probability(AP)of 1.2%,and a timing jitter of 216 ps are achieved,demonstrating excellent single photon detection performance. 展开更多
关键词 single-photon avalanche diode(SPAD) fill factor(FF) photon detection efficiency(PDE) dark count rate(DCR)
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Automated Counting of Rice Planthoppers in Paddy Fields Based on Image Processing 被引量:22
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作者 YAO Qing XIAN Ding-xiang +3 位作者 LIU Qing-jie YANG Bao-jun DIAO Guang-qiang TANG Jian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第8期1736-1745,共10页
A quantitative survey of rice planthoppers in paddy fields is important to assess the population density and make forecasting decisions. Manual rice planthopper survey methods in paddy fields are time-consuming, fatig... A quantitative survey of rice planthoppers in paddy fields is important to assess the population density and make forecasting decisions. Manual rice planthopper survey methods in paddy fields are time-consuming, fatiguing and tedious. This paper describes a handheld device for easily capturing planthopper images on rice stems and an automatic method for counting rice planthoppers based on image processing. The handheld device consists of a digital camera with WiFi, a smartphone and an extrendable pole. The surveyor can use the smartphone to control the camera, which is fixed on the front of the pole by WiFi, and to photograph planthoppers on rice stems. For the counting of planthoppers on rice stems, we adopt three layers of detection that involve the following:(a) the first layer of detection is an AdaBoost classifier based on Haar features;(b) the second layer of detection is a support vector machine(SVM) classifier based on histogram of oriented gradient(HOG) features;(c) the third layer of detection is the threshold judgment of the three features. We use this method to detect and count whiteback planthoppers(Sogatella furcifera) on rice plant images and achieve an 85.2% detection rate and a 9.6% false detection rate. The method is easy, rapid and accurate for the assessment of the population density of rice planthoppers in paddy fields. 展开更多
关键词 insect counting rice planthoppers handheld device AdaBoost classifier SVM classifier image features
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基于Counting Bloom Filter的海量网页快速去重研究 被引量:1
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作者 吴家奇 刘年国 +2 位作者 李雪 谢翔 王涛 《电力大数据》 2018年第12期37-42,共6页
网页去重是从给定的大量的数据集合中检测出冗余的网页,然后将冗余的网页从该数据集合中去除的过程,可以有效地减少检索和存储的压力。其中基于同源网页的URL去重方法、基于网页结构和特征的抽取指纹方法和基于网页内容的聚类方法的研... 网页去重是从给定的大量的数据集合中检测出冗余的网页,然后将冗余的网页从该数据集合中去除的过程,可以有效地减少检索和存储的压力。其中基于同源网页的URL去重方法、基于网页结构和特征的抽取指纹方法和基于网页内容的聚类方法的研究都已经取得了很大的发展,但是针对海量网页去重问题,上述三种方法,目前还是很难解决网页去重的时间和空间问题,本文在基于MD5指纹库网页去重算法的基础上,结合Counting Bloom filter算法的特性,提出一个节省空间的大规模数据表示和快速去重策略,实现了一种快速去重算法IMP-CM Filter,大大降低了网页去重算法的时间复杂度和空间复杂度。该算法通过减少I/0频繁操作,来提高海量网页去重的效率。最后通过实验表明,IMP-CM Filter算法的有效性。 展开更多
关键词 网页去重 MD5指纹库 counting BLOOM filter IMP-CM Filter算法
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Recent progress of SiC UV single photon counting avalanche photodiodes 被引量:9
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作者 Linlin Su Dong Zhou +2 位作者 Hai Lu Rong Zhang Youdou Zheng 《Journal of Semiconductors》 EI CAS CSCD 2019年第12期59-69,共11页
4H-SiC single photon counting avalanche photodiodes(SPADs)are prior devices for weak ultraviolet(UV)signal detection with the advantages of small size,low leakage current,high avalanche multiplication gain,and high qu... 4H-SiC single photon counting avalanche photodiodes(SPADs)are prior devices for weak ultraviolet(UV)signal detection with the advantages of small size,low leakage current,high avalanche multiplication gain,and high quantum efficiency,which benefit from the large bandgap energy,high carrier drift velocity and excellent physical stability of 4 H-SiC semiconductor material.UV detectors are widely used in many key applications,such as missile plume detection,corona discharge,UV astronomy,and biological and chemical agent detection.In this paper,we will describe basic concepts and review recent results on device design,process development,and basic characterizations of 4 H-SiC avalanche photodiodes.Several promising device structures and uniformity of avalanche multiplication are discussed,which are important for achieving high performance of 4 HSiC UV SPADs. 展开更多
关键词 SIC avalanche photodiodes single photon counting ultraviolet detection
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Evolution of the Late Cretaceous Yongfeng-Chongren Basin in Jiangxi Province,southeast China: insights from sedimentary facies analysis and pebble counting 被引量:11
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作者 CHEN Liu-qin GUO Fu-sheng TANG Chao 《Journal of Mountain Science》 SCIE CSCD 2016年第2期342-351,共10页
The Gan-Hang Belt in Southeast China is characterized by several igneous and siliciclastic basins associated with crustal extension during Late Mesozoic. The sedimentary evolution of the red basins is still poorly und... The Gan-Hang Belt in Southeast China is characterized by several igneous and siliciclastic basins associated with crustal extension during Late Mesozoic. The sedimentary evolution of the red basins is still poorly understood. In this study, sedimentary fades analysis and pebble counting were performed on outcrop sections of the Late Cretaceous Guifeng Group in the Yongfeng-Chongren Basin in central Jiangxi Province. Thirty-five conglomerate outcrops were chosen to measure pebble lithology, size, roundness, weathering degree and preferred orientation. Results show that gravels are mostly fine to coarse pebbles and comprise dominantly quartzites, metamorphic rocks, granitoids and sandstones. Rose diagrams based on imbricated pebbles indicate variable paleocurrent directions. Combining with typical sedimentary structures and vertical successions, we suggest that the Guifeng Group were deposited in alluvial fan, river and playa lake depositional systems. The proposed depositional model indicates that the Hekou Formation represents the start-up stage of the faulted basin, accompanied by sedimentation in alluvial fan and braided river environments. Then this basin turned into a stable expansion stage during the deposition of the Tangbian Formation. Except for minor coarse sediments at the basin margin, the other area is covered with fine-grained sediments of lake and river environments. The Lianhe Formation, however, is once again featured by conglomerates, suggesting a probable tectonic event. Therefore, the study region possibly suffered two tectonic events represented by the conglomerates of the Hekou and Lianhe formations in the context of the crustal extension in Southeast China. 展开更多
关键词 Late Cretaceous redbeds Pebble counting Yongfeng-Chongren Basin Gan-Hang Belt Geological evolution
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Filtering Method of Aero⁃engine Load Spectrum Based on Rain Flow Counting 被引量:4
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作者 XU Cong SUN Zhigang +1 位作者 LU Qi SONG Yingdong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第6期947-954,共8页
A filtering method of aero-engine load spectrum based on the rain flow counting is proposed in this paper.Firstly,the original load spectrum is counted through the rain flow method to get the peak and valley values.Th... A filtering method of aero-engine load spectrum based on the rain flow counting is proposed in this paper.Firstly,the original load spectrum is counted through the rain flow method to get the peak and valley values.Then,some data points in the original load spectrum are added between the peak and valley values.Finally,the filtering spectrum is obtained.The proposed method can reflect the path information of the original load spectrum.In addition,it can also eliminate the noise in the signal and improve the efficiency of signal processing,which is of practical significance for the research of aero-engine. 展开更多
关键词 load spectrum FILTERING rain flow counting AERO-ENGINE
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