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Deep Learning Based Efficient Crowd Counting System
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作者 Waleed Khalid Al-Ghanem Emad Ul Haq Qazi +1 位作者 Muhammad Hamza Faheem Syed Shah Amanullah Quadri 《Computers, Materials & Continua》 SCIE EI 2024年第6期4001-4020,共20页
Estimation of crowd count is becoming crucial nowadays,as it can help in security surveillance,crowd monitoring,and management for different events.It is challenging to determine the approximate crowd size from an ima... Estimation of crowd count is becoming crucial nowadays,as it can help in security surveillance,crowd monitoring,and management for different events.It is challenging to determine the approximate crowd size from an image of the crowd’s density.Therefore in this research study,we proposed a multi-headed convolutional neural network architecture-based model for crowd counting,where we divided our proposed model into two main components:(i)the convolutional neural network,which extracts the feature across the whole image that is given to it as an input,and(ii)the multi-headed layers,which make it easier to evaluate density maps to estimate the number of people in the input image and determine their number in the crowd.We employed the available public benchmark crowd-counting datasets UCF CC 50 and ShanghaiTech parts A and B for model training and testing to validate the model’s performance.To analyze the results,we used two metrics Mean Absolute Error(MAE)and Mean Square Error(MSE),and compared the results of the proposed systems with the state-of-art models of crowd counting.The results show the superiority of the proposed system. 展开更多
关键词 Crowd counting EfficientNet multi-head attention convolutional neural network transfer learning
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A multi-source information fusion layer counting method for penetration fuze based on TCN-LSTM
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作者 Yili Wang Changsheng Li Xiaofeng Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期463-474,共12页
When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ... When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of layers.To address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent network.By leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration process.The analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,respectively.The model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target plates.The maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed model.Moreover,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves. 展开更多
关键词 Penetration fuze Temporal convolutional network(TCN) Long short-term memory(LSTM) Layer counting Multi-source fusion
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Lightweight Res-Connection Multi-Branch Network for Highly Accurate Crowd Counting and Localization
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作者 Mingze Li Diwen Zheng Shuhua Lu 《Computers, Materials & Continua》 SCIE EI 2024年第5期2105-2122,共18页
Crowd counting is a promising hotspot of computer vision involving crowd intelligence analysis,achieving tremendous success recently with the development of deep learning.However,there have been stillmany challenges i... Crowd counting is a promising hotspot of computer vision involving crowd intelligence analysis,achieving tremendous success recently with the development of deep learning.However,there have been stillmany challenges including crowd multi-scale variations and high network complexity,etc.To tackle these issues,a lightweight Resconnection multi-branch network(LRMBNet)for highly accurate crowd counting and localization is proposed.Specifically,using improved ShuffleNet V2 as the backbone,a lightweight shallow extractor has been designed by employing the channel compression mechanism to reduce enormously the number of network parameters.A light multi-branch structure with different expansion rate convolutions is demonstrated to extract multi-scale features and enlarged receptive fields,where the information transmission and fusion of diverse scale features is enhanced via residual concatenation.In addition,a compound loss function is introduced for training themethod to improve global context information correlation.The proposed method is evaluated on the SHHA,SHHB,UCF-QNRF and UCF_CC_50 public datasets.The accuracy is better than those of many advanced approaches,while the number of parameters is smaller.The experimental results show that the proposed method achieves a good tradeoff between the complexity and accuracy of crowd counting,indicating a lightweight and high-precision method for crowd counting. 展开更多
关键词 Crowd counting Res-connection multi-branch compound loss function
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Counting of alpha particle tracks on imaging plate based on a convolutional neural network 被引量:1
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作者 Feng-Di Qin Han-Yu Luo +5 位作者 Zheng-Zhong He Ke-Jun Lu Chuan-Gao Wang Meng-Meng Wu Zhong-Kai Fan Jian Shan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第3期52-63,共12页
Imaging plates are widely used to detect alpha particles to track information,and the number of alpha particle tracks is affected by the overlapping and fading effects of the track information.In this study,an experim... Imaging plates are widely used to detect alpha particles to track information,and the number of alpha particle tracks is affected by the overlapping and fading effects of the track information.In this study,an experiment and a simulation were used to calibrate the efficiency parameter of an imaging plate,which was used to calculate the grayscale.Images were created by using grayscale,which trained the convolutional neural network to count the alpha tracks.The results demonstrated that the trained convolutional neural network can evaluate the alpha track counts based on the source and background images with a wider linear range,which was unaffected by the overlapping effect.The alpha track counts were unaffected by the fading effect within 60 min,where the calibrated formula for the fading effect was analyzed for 132.7 min.The detection efficiency of the trained convolutional neural network for inhomogeneous ^(241)Am sources(2π emission)was 0.6050±0.0399,whereas the efficiency curve of the photo-stimulated luminescence method was lower than that of the trained convolutional neural network. 展开更多
关键词 Imaging plate Convolutional neural network Alpha tracks counting
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RPNet: Rice plant counting after tillering stage based on plant attention and multiple supervision network
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作者 Xiaodong Bai Susong Gu +4 位作者 Pichao Liu Aiping Yang Zhe Cai Jianjun Wang Jianguo Yao 《The Crop Journal》 SCIE CSCD 2023年第5期1586-1594,共9页
Rice is a major food crop and is planted worldwide. Climatic deterioration, population growth, farmland shrinkage, and other factors have necessitated the application of cutting-edge technology to achieve accurate and... Rice is a major food crop and is planted worldwide. Climatic deterioration, population growth, farmland shrinkage, and other factors have necessitated the application of cutting-edge technology to achieve accurate and efficient rice production. In this study, we mainly focus on the precise counting of rice plants in paddy field and design a novel deep learning network, RPNet, consisting of four modules: feature encoder, attention block, initial density map generator, and attention map generator. Additionally, we propose a novel loss function called RPloss. This loss function considers the magnitude relationship between different sub-loss functions and ensures the validity of the designed network. To verify the proposed method, we conducted experiments on our recently presented URC dataset, which is an unmanned aerial vehicle dataset that is quite challenged at counting rice plants. For experimental comparison, we chose some popular or recently proposed counting methods, namely MCNN, CSRNet, SANet, TasselNetV2, and FIDTM. In the experiment, the mean absolute error(MAE), root mean squared error(RMSE), relative MAE(rMAE) and relative RMSE(rRMSE) of the proposed RPNet were 8.3, 11.2, 1.2% and 1.6%, respectively,for the URC dataset. RPNet surpasses state-of-the-art methods in plant counting. To verify the universality of the proposed method, we conducted experiments on the well-know MTC and WED datasets. The final results on these datasets showed that our network achieved the best results compared with excellent previous approaches. The experiments showed that the proposed RPNet can be utilized to count rice plants in paddy fields and replace traditional methods. 展开更多
关键词 RICE Precision agriculture Plant counting Deep learning Attention mechanism
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A Deep Learning-Based Crowd Counting Method and System Implementation on Neural Processing Unit Platform
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作者 Yuxuan Gu Meng Wu +2 位作者 Qian Wang Siguang Chen Lijun Yang 《Computers, Materials & Continua》 SCIE EI 2023年第4期493-512,共20页
In this paper, a deep learning-based method is proposed for crowdcountingproblems. Specifically, by utilizing the convolution kernel densitymap, the ground truth is generated dynamically to enhance the featureextracti... In this paper, a deep learning-based method is proposed for crowdcountingproblems. Specifically, by utilizing the convolution kernel densitymap, the ground truth is generated dynamically to enhance the featureextractingability of the generator model. Meanwhile, the “cross stage partial”module is integrated into congested scene recognition network (CSRNet) toobtain a lightweight network model. In addition, to compensate for the accuracydrop owing to the lightweight model, we take advantage of “structuredknowledge transfer” to train the model in an end-to-end manner. It aimsto accelerate the fitting speed and enhance the learning ability of the studentmodel. The crowd-counting system solution for edge computing is alsoproposed and implemented on an embedded device equipped with a neuralprocessing unit. Simulations demonstrate the performance improvement ofthe proposed solution in terms of model size, processing speed and accuracy.The performance on the Venice dataset shows that the mean absolute error(MAE) and the root mean squared error (RMSE) of our model drop by32.63% and 39.18% compared with CSRNet. Meanwhile, the performance onthe ShanghaiTech PartB dataset reveals that the MAE and the RMSE of ourmodel are close to those of CSRNet. Therefore, we provide a novel embeddedplatform system scheme for public safety pre-warning applications. 展开更多
关键词 Crowd counting CSRNet dynamic density map lightweight model knowledge transfer
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A new software for automated counting of glistenings in intraocular lenses in vivo
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作者 Nick Stanojcic Christopher C.Hull +2 位作者 Eduardo Mangieri Nathan Little David O’Brart 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第8期1237-1242,共6页
AIM:To assess the performance of a bespoke software for automated counting of intraocular lens(IOL)glistenings in slit-lamp images.METHODS:IOL glistenings from slit-lamp-derived digital images were counted manually an... AIM:To assess the performance of a bespoke software for automated counting of intraocular lens(IOL)glistenings in slit-lamp images.METHODS:IOL glistenings from slit-lamp-derived digital images were counted manually and automatically by the bespoke software.The images of one randomly selected eye from each of 34 participants were used as a training set to determine the threshold setting that gave the best agreement between manual and automatic grading.A second set of 63 images,selected using randomised stratified sampling from 290 images,were used for software validation.The images were obtained using a previously described protocol.Software-derived automated glistenings counts were compared to manual counts produced by three ophthalmologists.RESULTS:A threshold value of 140 was determined that minimised the total deviation in the number of glistenings for the 34 images in the training set.Using this threshold value,only slight agreement was found between automated software counts and manual expert counts for the validating set of 63 images(κ=0.104,95%CI,0.040-0.168).Ten images(15.9%)had glistenings counts that agreed between the software and manual counting.There were 49 images(77.8%)where the software overestimated the number of glistenings.CONCLUSION:The low levels of agreement show between an initial release of software used to automatically count glistenings in in vivo slit-lamp images and manual counting indicates that this is a non-trivial application.Iterative improvement involving a dialogue between software developers and experienced ophthalmologists is required to optimise agreement.The results suggest that validation of software is necessary for studies involving semi-automatic evaluation of glistenings. 展开更多
关键词 new software automated counting glistenings intraocular lenses slit-lamp images
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A Computer Vision-Based System for Metal Sheet Pick Counting
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作者 Jirasak Ji Warut Pannakkong Jirachai Buddhakulsomsiri 《Computers, Materials & Continua》 SCIE EI 2023年第5期3643-3656,共14页
Inventory counting is crucial to manufacturing industries in terms of inventory management,production,and procurement planning.Many companies currently require workers to manually count and track the status of materia... Inventory counting is crucial to manufacturing industries in terms of inventory management,production,and procurement planning.Many companies currently require workers to manually count and track the status of materials,which are repetitive and non-value-added activities but incur significant costs to the companies as well as mental fatigue to the employees.This research aims to develop a computer vision system that can automate the material counting activity without applying any marker on the material.The type of material of interest is metal sheet,whose shape is simple,a large rectangular shape,yet difficult to detect.The use of computer vision technology can reduce the costs incurred fromthe loss of high-value materials,eliminate repetitive work requirements for skilled labor,and reduce human error.A computer vision system is proposed and tested on a metal sheet picking process formultiple metal sheet stacks in the storage area by using one video camera.Our results show that the proposed computer vision system can count the metal sheet picks under a real situation with a precision of 97.83%and a recall of 100%. 展开更多
关键词 Computer vision manual operation operation monitoring material counting
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Lightweight Fish Bait Particle Counting Method Based on Pruning and Shift Quantization
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作者 Siyue Hou Yaqian Wang +2 位作者 Bingqian Zhou Dong An Yaoguang Wei 《Journal of Beijing Institute of Technology》 EI CAS 2023年第3期313-327,共15页
In the process of aquaculture,monitoring the number of fish bait particles is of great significance to improve the growth and welfare of fish.Although the counting method based on onvolutional neural network(CNN)achie... In the process of aquaculture,monitoring the number of fish bait particles is of great significance to improve the growth and welfare of fish.Although the counting method based on onvolutional neural network(CNN)achieve good accuracy and applicability,it has a high amount of parameters and computation,which limit the deployment on resource-constrained hardware devices.In order to solve the above problems,this paper proposes a lightweight bait particle counting method based on shift quantization and model pruning strategies.Firstly,we take corresponding lightweight strategies for different layers to flexibly balance the counting accuracy and performance of the model.In order to deeply lighten the counting model,the redundant and less informative weights of the model are removed through the combination of model quantization and pruning.The experimental results show that the compression rate is nearly 9 times.Finally,the quantization candidate value is refined by introducing a power-of-two addition term,which improves the matches of the weight distribution.By analyzing the experimental results,the counting loss at 3 bit is reduced by 35.31%.In summary,the lightweight bait particle counting model proposed in this paper achieves lossless counting accuracy and reduces the storage and computational overhead required for running convolutional neural networks. 展开更多
关键词 AQUACULTURE deep learning feed particles counting model slimming
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Robust Counting in Overcrowded Scenes Using Batch-Free Normalized Deep ConvNet
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作者 Sana Zahir Rafi Ullah Khan +4 位作者 Mohib Ullah Muhammad Ishaq Naqqash Dilshad Amin Ullah Mi Young Lee 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期2741-2754,共14页
The analysis of overcrowded areas is essential for flow monitoring,assembly control,and security.Crowd counting’s primary goal is to calculate the population in a given region,which requires real-time analysis of con... The analysis of overcrowded areas is essential for flow monitoring,assembly control,and security.Crowd counting’s primary goal is to calculate the population in a given region,which requires real-time analysis of congested scenes for prompt reactionary actions.The crowd is always unexpected,and the benchmarked available datasets have a lot of variation,which limits the trained models’performance on unseen test data.In this paper,we proposed an end-to-end deep neural network that takes an input image and generates a density map of a crowd scene.The proposed model consists of encoder and decoder networks comprising batch-free normalization layers known as evolving normalization(EvoNorm).This allows our network to be generalized for unseen data because EvoNorm is not using statistics from the training samples.The decoder network uses dilated 2D convolutional layers to provide large receptive fields and fewer parameters,which enables real-time processing and solves the density drift problem due to its large receptive field.Five benchmark datasets are used in this study to assess the proposed model,resulting in the conclusion that it outperforms conventional models. 展开更多
关键词 Artificial intelligence deep learning crowd counting scene understanding
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Improvement of Counting Sorting Algorithm
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作者 Chenglong Song Haiming Li 《Journal of Computer and Communications》 2023年第10期12-22,共11页
By analyzing the internal features of counting sorting algorithm. Two improvements of counting sorting algorithms are proposed, which have a wide range of applications and better efficiency than the original counting ... By analyzing the internal features of counting sorting algorithm. Two improvements of counting sorting algorithms are proposed, which have a wide range of applications and better efficiency than the original counting sort while maintaining the original stability. Compared with the original counting sort, it has a wider scope of application and better time and space efficiency. In addition, the accuracy of the above conclusions can be proved by a large amount of experimental data. 展开更多
关键词 Sort Algorithm counting Sorting Algorithms COMPLEXITY Internal Features
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Fatigue Safety Assessment of Concrete Continuous Rigid Frame Bridge Based on Rain Flow Counting Method and Health Monitoring Data
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作者 Yinghua Li Junyong He +1 位作者 Xiaoqing Zeng Yanxing Tang 《Journal of Architectural Environment & Structural Engineering Research》 2023年第3期31-40,共10页
The fatigue of concrete structures will gradually appear after being subjected to alternating loads for a long time,and the accidents caused by fatigue failure of bridge structures also appear from time to time.Aiming... The fatigue of concrete structures will gradually appear after being subjected to alternating loads for a long time,and the accidents caused by fatigue failure of bridge structures also appear from time to time.Aiming at the problem of degradation of long-span continuous rigid frame bridges due to fatigue and environmental effects,this paper suggests a method to analyze the fatigue degradation mechanism of this type of bridge,which combines long-term in-site monitoring data collected by the health monitoring system(HMS)and fatigue theory.In the paper,the authors mainly carry out the research work in the following aspects:First of all,a long-span continuous rigid frame bridge installed with HMS is used as an example,and a large amount of health monitoring data have been acquired,which can provide efficient information for fatigue in terms of equivalent stress range and cumulative number of stress cycles;next,for calculating the cumulative fatigue damage of the bridge structure,fatigue stress spectrum got by rain flow counting method,S-N curves and damage criteria are used for fatigue damage analysis.Moreover,it was considered a linear accumulation damage through the Palmgren-Miner rule for the counting of stress cycles.The health monitoring data are adopted to obtain fatigue stress data and the rain flow counting method is used to count the amplitude varying fatigue stress.The proposed fatigue reliability approach in the paper can estimate the fatigue damage degree and its evolution law of bridge structures well,and also can help bridge engineers do the assessment of future service duration. 展开更多
关键词 Long-span continuous rigid frame bridge Rain flow counting method Fatigue performance Health monitoring system Strain monitoring data
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Modeling the photon counting and photoelectron counting characteristics of quanta image sensors 被引量:1
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作者 Bowen Liu Jiangtao Xu 《Journal of Semiconductors》 EI CAS CSCD 2021年第6期25-34,共10页
A signal chain model of single-bit and multi-bit quanta image sensors(QISs)is established.Based on the proposed model,the photoresponse characteristics and signal error rates of QISs are investigated,and the effects o... A signal chain model of single-bit and multi-bit quanta image sensors(QISs)is established.Based on the proposed model,the photoresponse characteristics and signal error rates of QISs are investigated,and the effects of bit depth,quantum efficiency,dark current,and read noise on them are analyzed.When the signal error rates towards photons and photoelectrons counting are lower than 0.01,the high accuracy photon and photoelectron counting exposure ranges are determined.Furthermore,an optimization method of integration time to ensure that the QIS works in these high accuracy exposure ranges is presented.The trade-offs between pixel area,the mean value of incident photons,and integration time under different illuminance level are analyzed.For the 3-bit QIS with 0.16 e-/s dark current and 0.21 e-r.m.s.read noise,when the illuminance level and pixel area are 1 lux and 1.21μm^(2),or 10000 lux and 0.21μm^(2),the recommended integration time is 8.8 to 30 ms,or 10 to21.3μs,respectively.The proposed method can guide the design and operation of single-bit and multi-bit QISs. 展开更多
关键词 CMOS image sensor quanta image sensor photon counting photoelectron counting signal error rate integration time
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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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Automated Counting of Rice Planthoppers in Paddy Fields Based on Image Processing 被引量:18
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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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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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Recent progress of SiC UV single photon counting avalanche photodiodes 被引量:7
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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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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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Accelerating Packet Classification with Counting Bloom Filters for Virtual Open Flow Switching 被引量:4
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作者 Jinyuan Zhao Zhigang Hu +1 位作者 Bing Xiong Keqin Li 《China Communications》 SCIE CSCD 2018年第10期117-128,共12页
The growing trend of network virtualization results in a widespread adoption of virtual switches in virtualized environments. However, virtual switching is confronted with great performance challenges regarding packet... The growing trend of network virtualization results in a widespread adoption of virtual switches in virtualized environments. However, virtual switching is confronted with great performance challenges regarding packet classification especially in Open Flow-based software defined networks. This paper first takes an insight into packet classification in virtual Open Flow switching, and points out that its performance bottleneck is dominated by flow table traversals of multiple failed mask probing for each arrived packet. Then we are motivated to propose an efficient packet classification algorithm based on counting bloom filters. In particular, counting bloom filters are applied to predict the failures of flow table lookups with great possibilities, and bypass flow table traversals for failed mask probing. Finally, our proposed packet classification algorithm is evaluated with real network traffic traces by experiments. The experimental results indicate that our proposed algorithm outperforms the classical one in Open v Switch in terms of average search length, and contributes to promote virtual Open Flow switching performance. 展开更多
关键词 OpenFlow virtual switching packet classification flow table lookups counting bloom filters
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