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COSINE多相场子通道程序格架模型开发与评估
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作者 陈林 张昊 +4 位作者 段秉祺 马齐超 周帆帆 杨燕华 赵萌 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第4期761-770,共10页
格架模型作为子通道程序中的重要模块,对大破口事故中再淹没工况下热工水力学参数的计算具有重要意义,COSINE多相场子通道程序包括格架的压降模型、壁面传热增强模型、相间传热增强模型、液滴破裂模型、格架再湿模型、格架温度模型等。... 格架模型作为子通道程序中的重要模块,对大破口事故中再淹没工况下热工水力学参数的计算具有重要意义,COSINE多相场子通道程序包括格架的压降模型、壁面传热增强模型、相间传热增强模型、液滴破裂模型、格架再湿模型、格架温度模型等。本研究选取棒束传热实验装置(RBHT)典型再淹没工况进行建模分析,评估格架模型对再淹没工况下热工水力学参数计算的影响。计算结果表明:采用格架模型后,程序计算的通道换热能力显著增强,格架模型可提高计算的骤冷前沿速度,加快包壳冷却及蒸汽温度的下降,并显著降低燃料包壳峰值温度(PCT),程序计算结果与实验数据符合良好;程序计算的格架温度变化趋势与实验值符合良好;程序中采用的液滴破裂模型可模拟格架前后的液滴尺寸变化,可精准预测液滴直径散射比;程序预测的格架附近液滴速度随时间的变化与实验趋势符合良好。COSINE多相场子通道程序中采用的格架模型可有效提高程序对再淹没工况下热工水力学参数的预测能力,程序中采用的格架模型是有效且合理可靠的。 展开更多
关键词 COSINE软件包 多相场子通道程序 格架模型 再淹没现象
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CAW-YOLO:Cross-Layer Fusion and Weighted Receptive Field-Based YOLO for Small Object Detection in Remote Sensing
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作者 Weiya Shi Shaowen Zhang Shiqiang Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3209-3231,共23页
In recent years,there has been extensive research on object detection methods applied to optical remote sensing images utilizing convolutional neural networks.Despite these efforts,the detection of small objects in re... In recent years,there has been extensive research on object detection methods applied to optical remote sensing images utilizing convolutional neural networks.Despite these efforts,the detection of small objects in remote sensing remains a formidable challenge.The deep network structure will bring about the loss of object features,resulting in the loss of object features and the near elimination of some subtle features associated with small objects in deep layers.Additionally,the features of small objects are susceptible to interference from background features contained within the image,leading to a decline in detection accuracy.Moreover,the sensitivity of small objects to the bounding box perturbation further increases the detection difficulty.In this paper,we introduce a novel approach,Cross-Layer Fusion and Weighted Receptive Field-based YOLO(CAW-YOLO),specifically designed for small object detection in remote sensing.To address feature loss in deep layers,we have devised a cross-layer attention fusion module.Background noise is effectively filtered through the incorporation of Bi-Level Routing Attention(BRA).To enhance the model’s capacity to perceive multi-scale objects,particularly small-scale objects,we introduce a weightedmulti-receptive field atrous spatial pyramid poolingmodule.Furthermore,wemitigate the sensitivity arising from bounding box perturbation by incorporating the joint Normalized Wasserstein Distance(NWD)and Efficient Intersection over Union(EIoU)losses.The efficacy of the proposedmodel in detecting small objects in remote sensing has been validated through experiments conducted on three publicly available datasets.The experimental results unequivocally demonstrate the model’s pronounced advantages in small object detection for remote sensing,surpassing the performance of current mainstream models. 展开更多
关键词 Small object detection attention mechanism cross-layer fusion discrete cosine transform
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Enhanced Differentiable Architecture Search Based on Asymptotic Regularization
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作者 Cong Jin Jinjie Huang +1 位作者 Yuanjian Chen Yuqing Gong 《Computers, Materials & Continua》 SCIE EI 2024年第2期1547-1568,共22页
In differentiable search architecture search methods,a more efficient search space design can significantly improve the performance of the searched architecture,thus requiring people to carefully define the search spa... In differentiable search architecture search methods,a more efficient search space design can significantly improve the performance of the searched architecture,thus requiring people to carefully define the search space with different complexity according to various operations.Meanwhile rationalizing the search strategies to explore the well-defined search space will further improve the speed and efficiency of architecture search.With this in mind,we propose a faster and more efficient differentiable architecture search method,AllegroNAS.Firstly,we introduce a more efficient search space enriched by the introduction of two redefined convolution modules.Secondly,we utilize a more efficient architectural parameter regularization method,mitigating the overfitting problem during the search process and reducing the error brought about by gradient approximation.Meanwhile,we introduce a natural exponential cosine annealing method to make the learning rate of the neural network training process more suitable for the search procedure.Moreover,group convolution and data augmentation are employed to reduce the computational cost.Finally,through extensive experiments on several public datasets,we demonstrate that our method can more swiftly search for better-performing neural network architectures in a more efficient search space,thus validating the effectiveness of our approach. 展开更多
关键词 Differentiable architecture search allegro search space asymptotic regularization natural exponential cosine annealing
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Machine-Learning Based Packet Switching Method for Providing Stable High-Quality Video Streaming in Multi-Stream Transmission
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作者 Yumin Jo Jongho Paik 《Computers, Materials & Continua》 SCIE EI 2024年第3期4153-4176,共24页
Broadcasting gateway equipment generally uses a method of simply switching to a spare input stream when a failure occurs in a main input stream.However,when the transmission environment is unstable,problems such as re... Broadcasting gateway equipment generally uses a method of simply switching to a spare input stream when a failure occurs in a main input stream.However,when the transmission environment is unstable,problems such as reduction in the lifespan of equipment due to frequent switching and interruption,delay,and stoppage of services may occur.Therefore,applying a machine learning(ML)method,which is possible to automatically judge and classify network-related service anomaly,and switch multi-input signals without dropping or changing signals by predicting or quickly determining the time of error occurrence for smooth stream switching when there are problems such as transmission errors,is required.In this paper,we propose an intelligent packet switching method based on the ML method of classification,which is one of the supervised learning methods,that presents the risk level of abnormal multi-stream occurring in broadcasting gateway equipment based on data.Furthermore,we subdivide the risk levels obtained from classification techniques into probabilities and then derive vectorized representative values for each attribute value of the collected input data and continuously update them.The obtained reference vector value is used for switching judgment through the cosine similarity value between input data obtained when a dangerous situation occurs.In the broadcasting gateway equipment to which the proposed method is applied,it is possible to perform more stable and smarter switching than before by solving problems of reliability and broadcasting accidents of the equipment and can maintain stable video streaming as well. 展开更多
关键词 Broadcasting and communication convergence multi-stream packet switching advanced television systems committee standard 3.0(ATSC 3.0) data pre-processing machine learning cosine similarity
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Fault Diagnosis Method of Rolling Bearing Based on ESGMD-CC and AFSA-ELM
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作者 Jiajie He Fuzheng Liu +3 位作者 Xiangyi Geng Xifeng Liang Faye Zhang Mingshun Jiang 《Structural Durability & Health Monitoring》 EI 2024年第1期37-54,共18页
Incomplete fault signal characteristics and ease of noise contamination are issues with the current rolling bearing early fault diagnostic methods,making it challenging to ensure the fault diagnosis accuracy and relia... Incomplete fault signal characteristics and ease of noise contamination are issues with the current rolling bearing early fault diagnostic methods,making it challenging to ensure the fault diagnosis accuracy and reliability.A novel approach integrating enhanced Symplectic geometry mode decomposition with cosine difference limitation and calculus operator(ESGMD-CC)and artificial fish swarm algorithm(AFSA)optimized extreme learning machine(ELM)is proposed in this paper to enhance the extraction capability of fault features and thus improve the accuracy of fault diagnosis.Firstly,SGMD decomposes the raw vibration signal into multiple Symplectic geometry components(SGCs).Secondly,the iterations are reset by the cosine difference limitation to effectively separate the redundant components from the representative components.Additionally,the calculus operator is performed to strengthen weak fault features and make them easier to extract,and the singular value decomposition(SVD)weighted by power spectrum entropy(PSE)can be utilized as the sample feature representation.Finally,AFSA iteratively optimized ELM is adopted as the optimized classifier for fault identification.The superior performance of the proposed method has been validated by various experiments. 展开更多
关键词 Symplectic geometry mode decomposition calculus operator cosine difference limitation fault diagnosis AFSAELM model
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Modeling a Periodic Signal Using Fourier Series
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作者 Uwaydah Leith 《Journal of Applied Mathematics and Physics》 2024年第3期841-860,共20页
This paper covers the concept of Fourier series and its application for a periodic signal. A periodic signal is a signal that repeats its pattern over time at regular intervals. The idea inspiring is to approximate a ... This paper covers the concept of Fourier series and its application for a periodic signal. A periodic signal is a signal that repeats its pattern over time at regular intervals. The idea inspiring is to approximate a regular periodic signal, under Dirichlet conditions, via a linear superposition of trigonometric functions, thus Fourier polynomials are constructed. The Dirichlet conditions, are a set of mathematical conditions, providing a foundational framework for the validity of the Fourier series representation. By understanding and applying these conditions, we can accurately represent and process periodic signals, leading to advancements in various areas of signal processing. The resulting Fourier approximation allows complex periodic signals to be expressed as a sum of simpler sinusoidal functions, making it easier to analyze and manipulate such signals. 展开更多
关键词 Fourier Series Signal PERIODIC PERIOD Frequency SINE COSINE CONVERGENCE
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A Dimensional Reduction Approach Based on Essential Constraints in Linear Programming
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作者 Eirini I. Nikolopoulou George S. Androulakis 《American Journal of Operations Research》 2024年第1期1-31,共31页
This paper presents a new dimension reduction strategy for medium and large-scale linear programming problems. The proposed method uses a subset of the original constraints and combines two algorithms: the weighted av... This paper presents a new dimension reduction strategy for medium and large-scale linear programming problems. The proposed method uses a subset of the original constraints and combines two algorithms: the weighted average and the cosine simplex algorithm. The first approach identifies binding constraints by using the weighted average of each constraint, whereas the second algorithm is based on the cosine similarity between the vector of the objective function and the constraints. These two approaches are complementary, and when used together, they locate the essential subset of initial constraints required for solving medium and large-scale linear programming problems. After reducing the dimension of the linear programming problem using the subset of the essential constraints, the solution method can be chosen from any suitable method for linear programming. The proposed approach was applied to a set of well-known benchmarks as well as more than 2000 random medium and large-scale linear programming problems. The results are promising, indicating that the new approach contributes to the reduction of both the size of the problems and the total number of iterations required. A tree-based classification model also confirmed the need for combining the two approaches. A detailed numerical example, the general numerical results, and the statistical analysis for the decision tree procedure are presented. 展开更多
关键词 Linear Programming Binding Constraints Dimension Reduction Cosine Similarity Decision Analysis Decision Trees
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Whole Perfect Vectors and Fermat’s Last Theorem
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作者 Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2024年第1期34-42,共9页
A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm de... A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm definition, and some vector-specific structures. 展开更多
关键词 Fermat’s Last Theorem Whole Perfect Vectors Sine and Cosine Functions Natural and Rational Vectors Fermat Vectors
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Sine Cosine Optimization with Deep Learning-Based Applied Linguistics for Sentiment Analysis on COVID-19 Tweets 被引量:1
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作者 Abdelwahed Motwakel Hala J.Alshahrani +5 位作者 Abdulkhaleq Q.A.Hassan Khaled Tarmissi Amal S.Mehanna Ishfaq Yaseen Amgad Atta Abdelmageed Mohammad Mahzari 《Computers, Materials & Continua》 SCIE EI 2023年第6期4767-4783,共17页
Applied linguistics is an interdisciplinary domain which identifies,investigates,and offers solutions to language-related real-life problems.The new coronavirus disease,otherwise known as Coronavirus disease(COVID-19)... Applied linguistics is an interdisciplinary domain which identifies,investigates,and offers solutions to language-related real-life problems.The new coronavirus disease,otherwise known as Coronavirus disease(COVID-19),has severely affected the everyday life of people all over the world.Specifically,since there is insufficient access to vaccines and no straight or reliable treatment for coronavirus infection,the country has initiated the appropriate preventive measures(like lockdown,physical separation,and masking)for combating this extremely transmittable disease.So,individuals spent more time on online social media platforms(i.e.,Twitter,Facebook,Instagram,LinkedIn,and Reddit)and expressed their thoughts and feelings about coronavirus infection.Twitter has become one of the popular social media platforms and allows anyone to post tweets.This study proposes a sine cosine optimization with bidirectional gated recurrent unit-based senti-ment analysis(SCOBGRU-SA)on COVID-19 tweets.The SCOBGRU-SA technique aimed to detect and classify the various sentiments in Twitter data during the COVID-19 pandemic.The SCOBGRU-SA technique follows data pre-processing and the Fast-Text word embedding process to accomplish this.Moreover,the BGRU model is utilized to recognise and classify sen-timents present in the tweets.Furthermore,the SCO algorithm is exploited for tuning the BGRU method’s hyperparameter,which helps attain improved classification performance.The experimental validation of the SCOBGRU-SA technique takes place using a benchmark dataset,and the results signify its promising performance compared to other DL models. 展开更多
关键词 Applied linguistics deep learning sentiment analysis COVID-19 pandemic sine cosine optimization TWITTER
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基于统计分布信息的上市公司随机缺失数据的KNN插补
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作者 李夏 汪晓云 +1 位作者 丁沈杰 张玥 《安徽工程大学学报》 CAS 2023年第4期90-94,共5页
数据缺失会为上市公司财务状况分析带来挑战。上市公司财务数据是兼具横截面和时间两个维度的面板数据,包含更多的统计分布信息。本文分别从多项式流形、参数假设检验、信息量3个视角,提出基于Cosine距离、HotellingT^(2)统计量、Jensen... 数据缺失会为上市公司财务状况分析带来挑战。上市公司财务数据是兼具横截面和时间两个维度的面板数据,包含更多的统计分布信息。本文分别从多项式流形、参数假设检验、信息量3个视角,提出基于Cosine距离、HotellingT^(2)统计量、Jensen-Shannon散度的3种KNN插补法,并对2021年第3季度至2022年第一季度的财务数据随机缺失状态下的插补性能进行验证。结果表明,缺失率较低时,Cosine距离的插补性能最优;缺失率较高时,HotellingT^(2)度量的插补性能最好。 展开更多
关键词 随机缺失 Cosine距离 HotellingT^(2)统计量 Jensen-Shannon散度
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Incorporating kernelized multi-omics data improves the accuracy of genomic prediction
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作者 Mang Liang Bingxing An +10 位作者 Tianpeng Chang Tianyu Deng Lili Du Keanning Li Sheng Cao Yueying Du Lingyang Xu Lupei Zhang Xue Gao Junya Li Huijiang Gao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期88-97,共10页
Background:Genomic selection(GS)has revolutionized animal and plant breeding after the first implementation via early selection before measuring phenotypes.Besides genome,transcriptome and metabolome information are i... Background:Genomic selection(GS)has revolutionized animal and plant breeding after the first implementation via early selection before measuring phenotypes.Besides genome,transcriptome and metabolome information are increasingly considered new sources for GS.Difficulties in building the model with multi-omics data for GS and the limit of specimen availability have both delayed the progress of investigating multi-omics.Results:We utilized the Cosine kernel to map genomic and transcriptomic data as n×n symmetric matrix(G matrix and T matrix),combined with the best linear unbiased prediction(BLUP)for GS.Here,we defined five kernel-based prediction models:genomic BLUP(GBLUP),transcriptome-BLUP(TBLUP),multi-omics BLUP(MBLUP,M=ratio×G+(1-ratio)×T),multi-omics single-step BLUP(mss BLUP),and weighted multi-omics single-step BLUP(wmss BLUP)to integrate transcribed individuals and genotyped resource population.The predictive accuracy evaluations in four traits of the Chinese Simmental beef cattle population showed that(1)MBLUP was far preferred to GBLUP(ratio=1.0),(2)the prediction accuracy of wmss BLUP and mss BLUP had 4.18%and 3.37%average improvement over GBLUP,(3)We also found the accuracy of wmss BLUP increased with the growing proportion of transcribed cattle in the whole resource population.Conclusions:We concluded that the inclusion of transcriptome data in GS had the potential to improve accuracy.Moreover,wmss BLUP is accepted to be a promising alternative for the present situation in which plenty of individuals are genotyped when fewer are transcribed. 展开更多
关键词 BLUP Cosine kernel Genomic prediction TRANSCRIPTOME
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A label noise filtering and label missing supplement framework based on game theory
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作者 Yuwen Liu Rongju Yao +4 位作者 Song Jia Fan Wang Ruili Wang Rui Ma Lianyong Qi 《Digital Communications and Networks》 SCIE CSCD 2023年第4期887-895,共9页
Labeled data is widely used in various classification tasks.However,there is a huge challenge that labels are often added artificially.Wrong labels added by malicious users will affect the training effect of the model... Labeled data is widely used in various classification tasks.However,there is a huge challenge that labels are often added artificially.Wrong labels added by malicious users will affect the training effect of the model.The unreliability of labeled data has hindered the research.In order to solve the above problems,we propose a framework of Label Noise Filtering and Missing Label Supplement(LNFS).And we take location labels in Location-Based Social Networks(LBSN)as an example to implement our framework.For the problem of label noise filtering,we first use FastText to transform the restaurant's labels into vectors,and then based on the assumption that the label most similar to all other labels in the location is most representative.We use cosine similarity to judge and select the most representative label.For the problem of label missing,we use simple common word similarity to judge the similarity of users'comments,and then use the label of the similar restaurant to supplement the missing labels.To optimize the performance of the model,we introduce game theory into our model to simulate the game between the malicious users and the model to improve the reliability of the model.Finally,a case study is given to illustrate the effectiveness and reliability of LNFS. 展开更多
关键词 Label noise FastText Cosine similarity Game theory LSTM
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Underwater acoustic signal denoising model based on secondary variational mode decomposition
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作者 Hong Yang Wen-shuai Shi Guo-hui Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第10期87-110,共24页
Due to the complexity of marine environment,underwater acoustic signal will be affected by complex background noise during transmission.Underwater acoustic signal denoising is always a difficult problem in underwater ... Due to the complexity of marine environment,underwater acoustic signal will be affected by complex background noise during transmission.Underwater acoustic signal denoising is always a difficult problem in underwater acoustic signal processing.To obtain a better denoising effect,a new denoising method of underwater acoustic signal based on optimized variational mode decomposition by black widow optimization algorithm(BVMD),fluctuation-based dispersion entropy threshold improved by Otsu method(OFDE),cosine similarity stationary threshold(CSST),BVMD,fluctuation-based dispersion entropy(FDE),named BVMD-OFDE-CSST-BVMD-FDE,is proposed.In the first place,decompose the original signal into a series of intrinsic mode functions(IMFs)by BVMD.Afterwards,distinguish pure IMFs,mixed IMFs and noise IMFs by OFDE and CSST,and reconstruct pure IMFs and mixed IMFs to obtain primary denoised signal.In the end,decompose primary denoising signal into IMFs by BVMD again,use the FDE value to distinguish noise IMFs and pure IMFs,and reconstruct pure IMFs to obtain the final denoised signal.The proposed mothod has three advantages:(i)BVMD can adaptively select the decomposition layer and penalty factor of VMD.(ii)FDE and CS are used as double criteria to distinguish noise IMFs from useful IMFs,and Otsu algorithm and CSST algorithm can effectively avoid the error caused by manually selecting thresholds.(iii)Secondary decomposition can make up for the deficiency of primary decomposition and further remove a small amount of noise.The chaotic signal and real ship signal are denoised.The experiment result shows that the proposed method can effectively denoise.It improves the denoising effect after primary decomposition,and has good practical value. 展开更多
关键词 Underwater acoustic signal DENOISING Variational mode decomposition Secondary decomposition Fluctuation-based dispersion entropy Cosine similarity
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Shape and Size Optimization of Truss Structures under Frequency Constraints Based on Hybrid Sine Cosine Firefly Algorithm
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作者 Ran Tao Xiaomeng Yang +1 位作者 Huanlin Zhou Zeng Meng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第1期405-428,共24页
Shape and size optimization with frequency constraints is a highly nonlinear problem withmixed design variables,non-convex search space,and multiple local optima.Therefore,a hybrid sine cosine firefly algorithm(HSCFA)... Shape and size optimization with frequency constraints is a highly nonlinear problem withmixed design variables,non-convex search space,and multiple local optima.Therefore,a hybrid sine cosine firefly algorithm(HSCFA)is proposed to acquire more accurate solutions with less finite element analysis.The full attraction model of firefly algorithm(FA)is analyzed,and the factors that affect its computational efficiency and accuracy are revealed.A modified FA with simplified attraction model and adaptive parameter of sine cosine algorithm(SCA)is proposed to reduce the computational complexity and enhance the convergence rate.Then,the population is classified,and different populations are updated by modified FA and SCA respectively.Besides,the random search strategy based on Lévy flight is adopted to update the stagnant or infeasible solutions to enhance the population diversity.Elitist selection technique is applied to save the promising solutions and further improve the convergence rate.Moreover,the adaptive penalty function is employed to deal with the constraints.Finally,the performance of HSCFA is demonstrated through the numerical examples with nonstructural masses and frequency constraints.The results show that HSCFA is an efficient and competitive tool for shape and size optimization problems with frequency constraints. 展开更多
关键词 Firefly algorithm sine cosine algorithm frequency constraints structural optimization
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Deep Learning Based Face Detection and Identification of Criminal Suspects
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作者 S.Sandhya A.Balasundaram Ayesha Shaik 《Computers, Materials & Continua》 SCIE EI 2023年第2期2331-2343,共13页
Occurrence of crimes has been on the constant rise despite the emerging discoveries and advancements in the technological field in the past decade.One of the most tedious tasks is to track a suspect once a crime is co... Occurrence of crimes has been on the constant rise despite the emerging discoveries and advancements in the technological field in the past decade.One of the most tedious tasks is to track a suspect once a crime is committed.As most of the crimes are committed by individuals who have a history of felonies,it is essential for a monitoring system that does not just detect the person’s face who has committed the crime,but also their identity.Hence,a smart criminal detection and identification system that makes use of the OpenCV Deep Neural Network(DNN)model which employs a Single Shot Multibox Detector for detection of face and an auto-encoder model in which the encoder part is used for matching the captured facial images with the criminals has been proposed.After detection and extraction of the face in the image by face cropping,the captured face is then compared with the images in the CriminalDatabase.The comparison is performed by calculating the similarity value between each pair of images that are obtained by using the Cosine Similarity metric.After plotting the values in a graph to find the threshold value,we conclude that the confidence rate of the encoder model is 0.75 and above. 展开更多
关键词 Deep learning OPENCV deep neural network single shot multi-box detector auto-encoder cosine similarity
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A Double Adaptive Random Spare Reinforced Sine Cosine Algorithm
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作者 Abdelazim G.Hussien Guoxi Liang +1 位作者 Huiling Chen Haiping Lin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2267-2289,共23页
Many complex optimization problems in the real world can easily fall into local optimality and fail to find the optimal solution,so more new techniques and methods are needed to solve such challenges.Metaheuristic alg... Many complex optimization problems in the real world can easily fall into local optimality and fail to find the optimal solution,so more new techniques and methods are needed to solve such challenges.Metaheuristic algorithms have received a lot of attention in recent years because of their efficient performance and simple structure.Sine Cosine Algorithm(SCA)is a recent Metaheuristic algorithm that is based on two trigonometric functions Sine&Cosine.However,like all other metaheuristic algorithms,SCA has a slow convergence and may fail in sub-optimal regions.In this study,an enhanced version of SCA named RDSCA is suggested that depends on two techniques:random spare/replacement and double adaptive weight.The first technique is employed in SCA to speed the convergence whereas the second method is used to enhance exploratory searching capabilities.To evaluate RDSCA,30 functions from CEC 2017 and 4 real-world engineering problems are used.Moreover,a nonparametric test called Wilcoxon signed-rank is carried out at 5%level to evaluate the significance of the obtained results between RDSCA and the other 5 variants of SCA.The results show that RDSCA has competitive results with other metaheuristics algorithms. 展开更多
关键词 Sine cosine algorithm global optimization swarm intelligence meta-heuristic algorithms
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A Large-Scale Scheduling Method for Multiple Agile Optical Satellites
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作者 Zheng Liu Wei Xiong Minghui Xiong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1143-1163,共21页
This study investigates the scheduling problem ofmultiple agile optical satelliteswith large-scale tasks.This problem is difficult to solve owing to the time-dependent characteristic of agile optical satellites,comple... This study investigates the scheduling problem ofmultiple agile optical satelliteswith large-scale tasks.This problem is difficult to solve owing to the time-dependent characteristic of agile optical satellites,complex constraints,and considerable solution space.To solve the problem,we propose a scheduling method based on an improved sine and cosine algorithm and a task merging approach.We first establish a scheduling model with task merging constraints and observation action constraints to describe the problem.Then,an improved sine and cosine algorithm is proposed to search for the optimal solution with the maximum profit ratio.An adaptive cosine factor and an adaptive greedy factor are adopted to improve the algorithm.Besides,a taskmerging method with a task reallocation mechanism is developed to improve the scheduling efficiency.Experimental results demonstrate the superiority of the proposed algorithm over the comparison algorithms. 展开更多
关键词 Multiple agile optical satellites scheduling task merging sine and cosine algorithm task reallocation
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Multi-scale Incremental Analysis Update Scheme and Its Application to Typhoon Mangkhut(2018)Prediction
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作者 Yan GAO Jiali FENG +4 位作者 Xin XIA Jian SUN Yulong MA Dongmei CHEN Qilin WAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期95-109,共15页
In the traditional incremental analysis update(IAU)process,all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time window.This approach effectively reduces high-f... In the traditional incremental analysis update(IAU)process,all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time window.This approach effectively reduces high-frequency oscillations introduced by data assimilation.However,as different scales of increments have unique evolutionary speeds and life histories in a numerical model,the traditional IAU scheme cannot fully meet the requirements of short-term forecasting for the damping of high-frequency noise and may even cause systematic drifts.Therefore,a multi-scale IAU scheme is proposed in this paper.Analysis increments were divided into different scale parts using a spatial filtering technique.For each scale increment,the optimal relaxation time in the IAU scheme was determined by the skill of the forecasting results.Finally,different scales of analysis increments were added to the model integration during their optimal relaxation time.The multi-scale IAU scheme can effectively reduce the noise and further improve the balance between large-scale and small-scale increments in the model initialization stage.To evaluate its performance,several numerical experiments were conducted to simulate the path and intensity of Typhoon Mangkhut(2018)and showed that:(1)the multi-scale IAU scheme had an obvious effect on noise control at the initial stage of data assimilation;(2)the optimal relaxation time for large-scale and small-scale increments was estimated as 6 h and 3 h,respectively;(3)the forecast performance of the multi-scale IAU scheme in the prediction of Typhoon Mangkhut(2018)was better than that of the traditional IAU scheme.The results demonstrate the superiority of the multi-scale IAU scheme. 展开更多
关键词 multi-scale incremental analysis updates optimal relaxation time 2-D discrete cosine transform GRAPES_MESO Typhoon Mangkhut(2018)
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IoT-Cloud Assisted Botnet Detection Using Rat Swarm Optimizer with Deep Learning
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作者 Saeed Masoud Alshahrani Fatma S.Alrayes +5 位作者 Hamed Alqahtani Jaber S.Alzahrani Mohammed Maray Sana Alazwari Mohamed A.Shamseldin Mesfer Al Duhayyim 《Computers, Materials & Continua》 SCIE EI 2023年第2期3085-3100,共16页
Nowadays,Internet of Things(IoT)has penetrated all facets of human life while on the other hand,IoT devices are heavily prone to cyberattacks.It has become important to develop an accurate system that can detect malic... Nowadays,Internet of Things(IoT)has penetrated all facets of human life while on the other hand,IoT devices are heavily prone to cyberattacks.It has become important to develop an accurate system that can detect malicious attacks on IoT environments in order to mitigate security risks.Botnet is one of the dreadfulmalicious entities that has affected many users for the past few decades.It is challenging to recognize Botnet since it has excellent carrying and hidden capacities.Various approaches have been employed to identify the source of Botnet at earlier stages.Machine Learning(ML)and Deep Learning(DL)techniques are developed based on heavy influence from Botnet detection methodology.In spite of this,it is still a challenging task to detect Botnet at early stages due to low number of features accessible from Botnet dataset.The current study devises IoT with Cloud Assisted Botnet Detection and Classification utilizingRat SwarmOptimizer with Deep Learning(BDC-RSODL)model.The presented BDC-RSODL model includes a series of processes like pre-processing,feature subset selection,classification,and parameter tuning.Initially,the network data is pre-processed to make it compatible for further processing.Besides,RSO algorithm is exploited for effective selection of subset of features.Additionally,Long Short TermMemory(LSTM)algorithm is utilized for both identification and classification of botnets.Finally,Sine Cosine Algorithm(SCA)is executed for fine-tuning the hyperparameters related to LSTM model.In order to validate the promising 3086 CMC,2023,vol.74,no.2 performance of BDC-RSODL system,a comprehensive comparison analysis was conducted.The obtained results confirmed the supremacy of BDCRSODL model over recent approaches. 展开更多
关键词 Internet of things cloud computing long short termmemory deep learning sine cosine algorithm feature selection
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HybridWatermarking and Encryption Techniques for Securing Medical Images
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作者 Amel Ali Alhussan Hanaa A.Abdallah +1 位作者 Sara Alsodairi Abdelhamied A.Ateya 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期403-416,共14页
Securing medical data while transmission on the network is required because it is sensitive and life-dependent data.Many methods are used for protection,such as Steganography,Digital Signature,Cryptography,and Waterma... Securing medical data while transmission on the network is required because it is sensitive and life-dependent data.Many methods are used for protection,such as Steganography,Digital Signature,Cryptography,and Watermarking.This paper introduces a novel robust algorithm that combines discrete wavelet transform(DWT),discrete cosine transform(DCT),and singular value decomposition(SVD)digital image-watermarking algorithms.The host image is decomposed using a two-dimensional DWT(2D-DWT)to approximate low-frequency sub-bands in the embedding process.Then the sub-band low-high(LH)is decomposed using 2D-DWT to four new sub-bands.The resulting sub-band low-high(LH1)is decomposed using 2D-DWT to four new sub-bands.Two frequency bands,high-high(HH_(2))and high-low(HL_(2)),are transformed by DCT,and then the SVD is applied to the DCT coefficients.The strongest modified singular values(SVs)vary very little for most attacks,which is an important property of SVD watermarking.The two watermark images are encrypted using two layers of encryption,circular and chaotic encryption techniques,to increase security.The first encrypted watermark is embedded in the S component of the DCT components of the HL_(2)coefficients.The second encrypted watermark is embedded in the S component of the DCT components of the HH2 coefficients.The suggested technique has been tested against various attacks and proven to provide excellent stability and imperceptibility results. 展开更多
关键词 WATERMARKING discrete wavelet transform discrete cosine transform singular value decomposition circular encryption chaotic encryption
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