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车站──刺激城市发展的动力源 被引量:1
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作者 Siegfried Tenner 胡晓嘉 《城市轨道交通研究》 2001年第3期89-91,共3页
关键词 城市发展 火车站 车站规划 车站设计 地铁车站 莱比锡车站
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DCT域图像水印:嵌入对策和算法 被引量:292
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作者 黄继武 Yun Q.SHI 程卫东 《电子学报》 EI CAS CSCD 北大核心 2000年第4期57-60,共4页
DCT域的隐形水印应嵌入哪里 ,水印才足够稳健 ?尽管许多关于DCT域水印算法的文献赞成水印应放在对视觉效果重要的分量 ,但DC分量总是被无一例外地排除在外 .本文提出了一个DCT域隐形水印的嵌入对策和一个应用该对策的自适应水印算法 .... DCT域的隐形水印应嵌入哪里 ,水印才足够稳健 ?尽管许多关于DCT域水印算法的文献赞成水印应放在对视觉效果重要的分量 ,但DC分量总是被无一例外地排除在外 .本文提出了一个DCT域隐形水印的嵌入对策和一个应用该对策的自适应水印算法 .基于对图像DCT系数振幅的定量分析 ,我们指出 :DC分量比任何AC分量有更大的感觉容量 ,从稳健性的角度 ,DC分量最适合用来嵌入水印 .应用这个对策 ,本文提出了一个把视觉系统纹理掩蔽特性结合到水印编码过程的自适应水印算法 .实验结果有效地支持了这个结论 ,所产生的隐形水印体现了很好的稳健性 . 展开更多
关键词 图像水印 嵌入对策 DCT域 加密算法
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基于匹配滤波的有意义图像水印算法 被引量:16
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作者 黄继武 G.F.Elmasry +1 位作者 程卫东 Yun Q.Shi 《电子学报》 EI CAS CSCD 北大核心 2001年第4期447-451,共5页
图像隐形水印是解决数字媒体版权保护的有效手段 .目前的大多数水印算法采用伪随机序列构成水印 ,因而只能给出“Yes”(有水印 )或“No”(无水印 )的回答 .嵌入有意义的水印在一些应用场合更加重要 ,但同时也带来了更多的困难 .嵌入有... 图像隐形水印是解决数字媒体版权保护的有效手段 .目前的大多数水印算法采用伪随机序列构成水印 ,因而只能给出“Yes”(有水印 )或“No”(无水印 )的回答 .嵌入有意义的水印在一些应用场合更加重要 ,但同时也带来了更多的困难 .嵌入有意义的水印必须解决二个问题 :(1)嵌入的水印具有一定的数据量 ;(2 )从有失真的水印图像中正确地提取嵌入的水印 .本文应用数字通信的理论和方法 ,提出了一个嵌入有意义字符串的DCT域隐形水印算法 .该算法采用BCH编码和匹配滤波来降低误码率 .应用所提出的算法 ,把一个 32个字符组成的水印嵌入到 2 5 6× 2 5 6的图像中并达到了较好的稳健性 .在水印图像信噪比受Gaussian加性噪声干扰下降到 2 6dB时 ,仍实现了对嵌入水印零错误概率的检测 . 展开更多
关键词 图像隐形水印 伪随机序列 匹配滤波 算法
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Long-term Coordination of Transmission and Storage to Integrate Wind Power 被引量:15
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作者 Antonio J.Conejo Yaohua Cheng +1 位作者 Ning Zhang Chongqing Kang 《CSEE Journal of Power and Energy Systems》 SCIE 2017年第1期36-43,共8页
A power system with a high wind power integration requires extra transmission capacity to accommodate the intermittency inherent to wind power production.Storage can smooth out this intermittency and reduce transmissi... A power system with a high wind power integration requires extra transmission capacity to accommodate the intermittency inherent to wind power production.Storage can smooth out this intermittency and reduce transmission requirements.This paper proposes a stochastic optimization model to coordinate the long-term planning of both transmission and storage facilities to efficiently integrate wind power.Both longterm and short-term uncertainties are considered in this model.Long-term uncertainty is described via scenarios,while shortterm uncertainty is described via operating conditions.Garver’s 6-node system and a system representing Northwest China in 2030 are used to illustrate the proposed model.Results indicate that storage reduces transmission requirement and the overall investment,and allows the efficient integration of wind power. 展开更多
关键词 Long-term planning STORAGE TRANSMISSION uncertainty wind power
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金属-半导体-金属(MSM)结构4H-SiC紫外光电探测器的研制 被引量:9
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作者 吴正云 XIN Xiao-bin +1 位作者 YAN Feng ZHAO Jian-hui 《量子电子学报》 CAS CSCD 北大核心 2004年第2期269-272,共4页
MSM结构探测器具有结构与工艺简单、制备成本低、量子效率高等特点而在探测器应用中得到重视。本文制备了采用镍作为肖特基接触形成的MSM 4H—SiC紫外光电探测器,并测量和分析了在不同的偏压下其光电特性。结果表明,该探测器的暗电流非... MSM结构探测器具有结构与工艺简单、制备成本低、量子效率高等特点而在探测器应用中得到重视。本文制备了采用镍作为肖特基接触形成的MSM 4H—SiC紫外光电探测器,并测量和分析了在不同的偏压下其光电特性。结果表明,该探测器的暗电流非常小,在偏压为15V的时候,漏电流密度约为70 nA/cm2,光电流比暗电流高约2个数量级,其光谱响应表明,其最高光谱响应与380 nm的比值约为1000倍,说明该探测器具有良好的紫外可见比。 展开更多
关键词 MSM 紫外光电探测器 4H-SIC 紫外可见比 宽禁带半导体
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Intelligent Wireless Communications Enabled by Cognitive Radio and Machine Learning 被引量:11
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作者 Xiangwei Zhou Mingxuan Sun +1 位作者 Geoffrey Ye Li Biing-Hwang (Fred) Juang 《China Communications》 SCIE CSCD 2018年第12期16-48,共33页
The ability to intelligently utilize resources to meet the need of growing diversity in services and user behavior marks the future of wireless communication systems. Intelligent wireless communications aims at enabli... The ability to intelligently utilize resources to meet the need of growing diversity in services and user behavior marks the future of wireless communication systems. Intelligent wireless communications aims at enabling the system to perceive and assess the available resources, to autonomously learn to adapt to the perceived wireless environment, and to reconfigure its operating mode to maximize the utility of the available resources. The perception capability and reconfigurability are the essential features of cognitive radio while modern machine learning techniques project great potential in system adaptation. In this paper, we discuss the development of the cognitive radio technology and machine learning techniques and emphasize their roles in improving spectrum and energy utility of wireless communication systems. We describe the state-of-the-art of relevant techniques, covering spectrum sensing and access approaches and powerful machine learning algorithms that enable spectrum and energy-efficient communications in dynamic wireless environments. We also present practical applications of these techniques and identify further research challenges in cognitive radio and machine learning as applied to the existing and future wireless communication systems. 展开更多
关键词 COGNITIVE RADIO energy EFFICIENCY machine learning RECONFIGURATION spectrum EFFICIENCY
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FD-MIMO距离高分辨雷达及其旁瓣抑制 被引量:8
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作者 戴喜增 许稼 +1 位作者 彭应宁 夏香根 《电子与信息学报》 EI CSCD 北大核心 2008年第9期2033-2037,共5页
为了提高距离分辨率而又不增加对发射/接收机带宽的要求,该文提出了频分多入多出(Frequency-Divided Multiple Input Multiple Output,FD-MIMO)雷达。该雷达利用同时发射的多路窄带信号合成宽带波形,进而得到目标的高分辨距离像。由于... 为了提高距离分辨率而又不增加对发射/接收机带宽的要求,该文提出了频分多入多出(Frequency-Divided Multiple Input Multiple Output,FD-MIMO)雷达。该雷达利用同时发射的多路窄带信号合成宽带波形,进而得到目标的高分辨距离像。由于持续时间短,合成高分辨距离像具有很好的多普勒容限。此外,针对由合成频谱不连续性造成的近区高旁瓣和由子带间耦合造成的远区高旁瓣,该文分别提出使用倒数谱滤波器和对子带信号加带外衰减的方法予以抑制。最后,理论分析和数值仿真证明了旁瓣抑制方法的有效性。 展开更多
关键词 频分多入多出雷达 模糊函数 高分辨距离像 倒数谱滤波
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Prediction of flyrock distance induced by mine blasting using a novel Harris Hawks optimization-based multi-layer perceptron neural network 被引量:9
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作者 Bhatawdekar Ramesh Murlidhar Hoang Nguyen +4 位作者 Jamal Rostami XuanNam Bui Danial Jahed Armaghani Prashanth Ragam Edy Tonnizam Mohamad 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第6期1413-1427,共15页
In mining or construction projects,for exploitation of hard rock with high strength properties,blasting is frequently applied to breaking or moving them using high explosive energy.However,use of explosives may lead t... In mining or construction projects,for exploitation of hard rock with high strength properties,blasting is frequently applied to breaking or moving them using high explosive energy.However,use of explosives may lead to the flyrock phenomenon.Flyrock can damage structures or nearby equipment in the surrounding areas and inflict harm to humans,especially workers in the working sites.Thus,prediction of flyrock is of high importance.In this investigation,examination and estimation/forecast of flyrock distance induced by blasting through the application of five artificial intelligent algorithms were carried out.One hundred and fifty-two blasting events in three open-pit granite mines in Johor,Malaysia,were monitored to collect field data.The collected data include blasting parameters and rock mass properties.Site-specific weathering index(WI),geological strength index(GSI) and rock quality designation(RQD)are rock mass properties.Multi-layer perceptron(MLP),random forest(RF),support vector machine(SVM),and hybrid models including Harris Hawks optimization-based MLP(known as HHO-MLP) and whale optimization algorithm-based MLP(known as WOA-MLP) were developed.The performance of various models was assessed through various performance indices,including a10-index,coefficient of determination(R^(2)),root mean squared error(RMSE),mean absolute percentage error(MAPE),variance accounted for(VAF),and root squared error(RSE).The a10-index values for MLP,RF,SVM,HHO-MLP and WOA-MLP are 0.953,0.933,0.937,0.991 and 0.972,respectively.R^(2) of HHO-MLP is 0.998,which achieved the best performance among all five machine learning(ML) models. 展开更多
关键词 Flyrock Harris hawks optimization(HHO) Multi-layer perceptron(MLP) Random forest(RF) Support vector machine(SVM) Whale optimization algorithm(WOA)
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一次中强磁暴期间低纬电离层响应的CT成像 被引量:8
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作者 徐继生 马淑英 +2 位作者 吴雄斌 林根煌 叶公节 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2000年第2期145-151,共7页
为考察赤道异常区电离层对中等强度磁暴的响应特性,用电离层CT成像方法重建电离层电子密度二维剖面.重建结果表明,暴时低纬电离层电子密度以降低为主,但暴相随纬度和高度而异;磁暴期间,赤道异常峰结构仍然存在,但恢复相期间峰... 为考察赤道异常区电离层对中等强度磁暴的响应特性,用电离层CT成像方法重建电离层电子密度二维剖面.重建结果表明,暴时低纬电离层电子密度以降低为主,但暴相随纬度和高度而异;磁暴期间,赤道异常峰结构仍然存在,但恢复相期间峰的位置向赤道移动;磁暴急始之后约20min,在赤道异常峰区出现电子密度深度耗空,这种耗空遍及从底到顶的整个F区,朝赤道一侧显现水平梯度非常大的陡壁.这种与磁暴急始相联系的电子密度深度耗空现象很有意义,值得进一步研究. 展开更多
关键词 低纬电离层 CT成像 磁暴 电离层暴
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Multimodality Medical Image Fusion Based on Pixel Significance with Edge-Preserving Processing for Clinical Applications
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作者 Bhawna Goyal Ayush Dogra +4 位作者 Dawa Chyophel Lepcha Rajesh Singh Hemant Sharma Ahmed Alkhayyat Manob Jyoti Saikia 《Computers, Materials & Continua》 SCIE EI 2024年第3期4317-4342,共26页
Multimodal medical image fusion has attained immense popularity in recent years due to its robust technology for clinical diagnosis.It fuses multiple images into a single image to improve the quality of images by reta... Multimodal medical image fusion has attained immense popularity in recent years due to its robust technology for clinical diagnosis.It fuses multiple images into a single image to improve the quality of images by retaining significant information and aiding diagnostic practitioners in diagnosing and treating many diseases.However,recent image fusion techniques have encountered several challenges,including fusion artifacts,algorithm complexity,and high computing costs.To solve these problems,this study presents a novel medical image fusion strategy by combining the benefits of pixel significance with edge-preserving processing to achieve the best fusion performance.First,the method employs a cross-bilateral filter(CBF)that utilizes one image to determine the kernel and the other for filtering,and vice versa,by considering both geometric closeness and the gray-level similarities of neighboring pixels of the images without smoothing edges.The outputs of CBF are then subtracted from the original images to obtain detailed images.It further proposes to use edge-preserving processing that combines linear lowpass filtering with a non-linear technique that enables the selection of relevant regions in detailed images while maintaining structural properties.These regions are selected using morphologically processed linear filter residuals to identify the significant regions with high-amplitude edges and adequate size.The outputs of low-pass filtering are fused with meaningfully restored regions to reconstruct the original shape of the edges.In addition,weight computations are performed using these reconstructed images,and these weights are then fused with the original input images to produce a final fusion result by estimating the strength of horizontal and vertical details.Numerous standard quality evaluation metrics with complementary properties are used for comparison with existing,well-known algorithms objectively to validate the fusion results.Experimental results from the proposed research article exhibit superior per 展开更多
关键词 Image fusion fractal data analysis BIOMEDICAL DISEASES research multiresolution analysis numerical analysis
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Analysis of Evolutionary Social Media Activities: Pre-Vaccine and Post-Vaccine Emergency Use 被引量:2
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作者 Haoyue Liu MengChu Zhou +2 位作者 Xiaoyu Lu Abdullah Abusorrah Yusuf Al-Turki 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第4期1090-1092,共3页
Dear Editor,In this letter,we analyze the public discourse sentiments over time and seek to understand the salient patterns around COVID-19 vaccines and vaccination from social media data.Globally,more than 373 millio... Dear Editor,In this letter,we analyze the public discourse sentiments over time and seek to understand the salient patterns around COVID-19 vaccines and vaccination from social media data.Globally,more than 373 million people have been diagnosed with COVID-19 and 5.66 million have died from this disease by 2022.It continues to have a negative impact on human daily life and the global economic development till now,due to the lack of effective treatment of COVID-19 induced issues and prevention of transmission methods. 展开更多
关键词 DISCOURSE methods PREVENTION
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Efficient Communication in Wireless Sensor Networks Using Optimized Energy Efficient Engroove Leach Clustering Protocol
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作者 N.Meenakshi Sultan Ahmad +5 位作者 A.V.Prabu J.Nageswara Rao Nashwan Adnan Othman Hikmat A.M.Abdeljaber R.Sekar Jabeen Nazeer 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2024年第4期985-1001,共17页
The Wireless Sensor Network(WSN)is a network that is constructed in regions that are inaccessible to human beings.The widespread deployment of wireless micro sensors will make it possible to conduct accurate environme... The Wireless Sensor Network(WSN)is a network that is constructed in regions that are inaccessible to human beings.The widespread deployment of wireless micro sensors will make it possible to conduct accurate environmental monitoring for a use in both civil and military environments.They make use of these data to monitor and keep track of the physical data of the surrounding environment in order to ensure the sustainability of the area.The data have to be picked up by the sensor,and then sent to the sink node where they may be processed.The nodes of the WSNs are powered by batteries,therefore they eventually run out of power.This energy restriction has an effect on the network life span and environmental sustainability.The objective of this study is to further improve the Engroove Leach(EL)protocol’s energy efficiency so that the network can operate for a very long time while consuming the least amount of energy.The lifespan of WSNs is being extended often using clustering and routing strategies.The Meta Inspired Hawks Fragment Optimization(MIHFO)system,which is based on passive clustering,is used in this study to do clustering.The cluster head is chosen based on the nodes’residual energy,distance to neighbors,distance to base station,node degree,and node centrality.Based on distance,residual energy,and node degree,an algorithm known as Heuristic Wing Antfly Optimization(HWAFO)selects the optimum path between the cluster head and Base Station(BS).They examine the number of nodes that are active,their energy consumption,and the number of data packets that the BS receives.The overall experimentation is carried out under the MATLAB environment.From the analysis,it has been discovered that the suggested approach yields noticeably superior outcomes in terms of throughput,packet delivery and drop ratio,and average energy consumption. 展开更多
关键词 wireless sensor networks energy efficient engroove leach protocol meta inspired Hawks fragment optimization heuristic wing antfly optimization
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QCA with reversible arithmetic and logic unit for nanoelectronics applications
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作者 Gade Mary Swarna Latha S.Rooban 《International Journal of Intelligent Computing and Cybernetics》 EI 2023年第1期139-157,共19页
Purpose-In this research work,brief quantum-dot cellular automata(QCA)concepts are discussed through arithmetic and logic units.This work is most useful for nanoelectronic applications,VLSI industry mainly depends on ... Purpose-In this research work,brief quantum-dot cellular automata(QCA)concepts are discussed through arithmetic and logic units.This work is most useful for nanoelectronic applications,VLSI industry mainly depends on this type of fault-tolerant QCA based arithmetic logic unit(ALU)design.The ALU design is mainly depending on set instructions and rules;these are maintained through low-power ultra-functional tricks only possible with QCA-based reversible arithmetic and logic unit for nanoelectronics.The main objective of this investigation is to design an ultra-low power and ultra-high-speed ALU design with QCA technology.The following QCA method has been implemented through reversible logic.Design/methodology/approach-QCA logic is the main and critical condition for realizing NANO-scale design that delivers considerably fast integrate module,effective performable computation and is less energy efficiency at the nano-scale(QCA).Processors need an ALU in order to process and calculate data.Faultresistant ALU in QCA technology utilizing reverse logic is the primary objective of this study.There are now two sections,i.e.reversible ALU(RAU),logical(LAU)and arithmetical(RAU).Findings-A reversible 231 multiplexer based on the Fredkin gate(FRG)was developed to allow users to choose between arithmetic and logical operations.QCA full adders are also implemented to improve arithmetic operations’performance.The ALU is built using reversible logic gates that are fault-tolerant.Originality/value-In contrast to earlier research,the suggested reversible multilayeredALU with reversible QCA operation is imported.The 8-and 16-bit ALU,as well as logical unit functioning,is designed through fewer gates,constant inputs and outputs.This implementation is designed on the Mentor Graphics QCA tool and verifies all functionalities. 展开更多
关键词 ALU QCA Fault tolerance Reversible logic
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A Chance-Constrained Wind Range Quantification Approach to Robust SCUC by Determining Dynamic Uncertainty Intervals 被引量:7
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作者 Aditi Upadhyay Bingqian Hu +1 位作者 Jie Li Lei Wu 《CSEE Journal of Power and Energy Systems》 SCIE 2016年第1期54-64,共11页
With increasing penetration of wind energy,the variability and uncertainty of wind resources have become important factors for power systems operation.In particular,an effective method is required for identifying the ... With increasing penetration of wind energy,the variability and uncertainty of wind resources have become important factors for power systems operation.In particular,an effective method is required for identifying the stochastic range of wind power output,in order to better guide the operational security of power systems.This paper proposes a metric to determine accurate wind power output ranges so that the probability of actual wind power outputs being out of the range would be less than a small pre-defined value.A mixed-integer linear programming(MILP)based chance-constrained optimization model is proposed for efficiently determining optimal wind power output ranges,which are quantified via maximum and the minimum wind generation levels with respect to a certain time interval.The derived wind power range is then used to construct dynamic uncertainty intervals for the robust securityconstrained unit commitment(SCUC)model.A comparison with the deterministic SCUC model and the traditional robust SCUC model with presumed static uncertainty interval demonstrates that the proposed approach can offer more accurate wind power variabilities(i.e.,different variability degrees with respect to different wind power output levels at different time periods).The proposed approach is also shown to offer more effective and robust SCUC solutions,guaranteeing operational security and economics of power systems.Numerical case studies on a 6-bus system and the modified IEEE 118-bus system with realworld wind power data illustrate the effectiveness of the proposed approach. 展开更多
关键词 Chance-constrained optimization MILP renewable energy integration SCUC wind power ranges
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Quasi noise-free digital holography 被引量:7
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作者 Vittorio Bianco Pasquale Memmolo +3 位作者 Melania Paturzo Andrea Finizio Bahram Javidi Pietro Ferraro 《Light(Science & Applications)》 SCIE EI CAS CSCD 2016年第1期506-517,共12页
One of the main drawbacks of Digital Holography(DH)is the coherent nature of the light source,which severely corrupts the quality of holographic reconstructions.Although numerous techniques to reduce noise in DH have ... One of the main drawbacks of Digital Holography(DH)is the coherent nature of the light source,which severely corrupts the quality of holographic reconstructions.Although numerous techniques to reduce noise in DH have provided good results,holographic noise suppression remains a challenging task.We propose a novel framework that combines the concepts of encoding multiple uncorrelated digital holograms,block grouping and collaborative filtering to achieve quasi noise-free DH reconstructions.The optimized joint action of these different image-denoising methods permits the removal of up to 98%of the noise while preserving the image contrast.The resulting quality of the hologram reconstructions is comparable to the quality achievable with non-coherent techniques and far beyond the current state of art in DH.Experimental validation is provided for both singlewavelength and multi-wavelength DH,and a comparison with the most used holographic denoising methods is performed. 展开更多
关键词 coherent noise reduction digital holography image reconstruction techniques multiplex holography noise in imaging systems SPECKLE
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Using a Software-Defined Air Interface Algorithm to Improve Service Quality 被引量:1
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作者 Madiraju Sirisha P.Abdul Khayum 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期1627-1641,共15页
In the digital era,the Narrowband Internet of Things(Nb-IoT)influ-ences the massive Machine-Type-Communication(mMTC)features to establish secure routing among the 5G/6G mobile networks.It supports global coverage to th... In the digital era,the Narrowband Internet of Things(Nb-IoT)influ-ences the massive Machine-Type-Communication(mMTC)features to establish secure routing among the 5G/6G mobile networks.It supports global coverage to the low-cost IoT devices distributed in terrestrial networks.Its key traffic char-acteristics include robust uplink,moderate data rate/device,extremely high energy efficiency,prolonging device lifetime,and Quality of Service(QoS).This paper proposes a Deep Reinforcement Learning(DRL)combined software-defined air interface algorithm applied on the switching system,satisfying the user require-ment and enabling them with the network resources to extend quality of service by choosing the most appropriate quality of service metric.In this framework,Non-Orthogonal Multiple Accesses(NOMA)and Rate-Splitting Multiple Access(RSMA)are combined to accommodate massive(Nb-IoT)devices that can be uti-lized the entire resource(frequency band)for tackling the unknown dynamics pro-hibitive.The proposed algorithm instantly assigns the network resources per user requirements and enhances selecting the best quality of service metric optimiza-tion.Therefore,it has potential benefits of high scalability,low latency,energy efficiency,and spectrum utility. 展开更多
关键词 DRL NOMA-RSMA nb-IoT mMTC QOS
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Grid Search for Predicting Coronary Heart Disease by Tuning Hyper-Parameters 被引量:2
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作者 S.Prabu B.Thiyaneswaran +2 位作者 M.Sujatha C.Nalini Sujatha Rajkumar 《Computer Systems Science & Engineering》 SCIE EI 2022年第11期737-749,共13页
Diagnosing the cardiovascular disease is one of the biggest medical difficulties in recent years.Coronary cardiovascular(CHD)is a kind of heart and blood vascular disease.Predicting this sort of cardiac illness leads ... Diagnosing the cardiovascular disease is one of the biggest medical difficulties in recent years.Coronary cardiovascular(CHD)is a kind of heart and blood vascular disease.Predicting this sort of cardiac illness leads to more precise decisions for cardiac disorders.Implementing Grid Search Optimization(GSO)machine training models is therefore a useful way to forecast the sickness as soon as possible.The state-of-the-art work is the tuning of the hyperparameter together with the selection of the feature by utilizing the model search to minimize the false-negative rate.Three models with a cross-validation approach do the required task.Feature Selection based on the use of statistical and correlation matrices for multivariate analysis.For Random Search and Grid Search models,extensive comparison findings are produced utilizing retrieval,F1 score,and precision measurements.The models are evaluated using the metrics and kappa statistics that illustrate the three models’comparability.The study effort focuses on optimizing function selection,tweaking hyperparameters to improve model accuracy and the prediction of heart disease by examining Framingham datasets using random forestry classification.Tuning the hyperparameter in the model of grid search thus decreases the erroneous rate achieves global optimization. 展开更多
关键词 Grid search coronary heart disease(CHD) machine learning feature selection hyperparameter tuning
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Survey of UAV motion planning 被引量:6
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作者 Lun Quan Luxin Han +2 位作者 Boyu Zhou Shaojie Shen Fei Gao 《IET Cyber-Systems and Robotics》 EI 2020年第1期14-21,共8页
Motion planning is a vital module for unmanned aerial vehicles(UAVs),especially in scenarios of autonomous navigation and operation.This survey delivers some recent state-of-the-art UAV motion planning algorithms and ... Motion planning is a vital module for unmanned aerial vehicles(UAVs),especially in scenarios of autonomous navigation and operation.This survey delivers some recent state-of-the-art UAV motion planning algorithms and related applications.The logic flow of this survey is divided as the path finding,which is the front-end of most motion planning systems,and the trajectory optimisation,which usually serves as the back-end.Motivation,methodology,problem formulation and derivation are given in this survey,in detail.Finally,a section about real-world applications is given,where roles and effectiveness of most popular motion planning methods are revealed. 展开更多
关键词 MOTION AUTONOMOUS FORMULATION
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COQ定理证明器辅助PLC程序验证和分析 被引量:6
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作者 陈钢 宋晓宇 顾明 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2010年第1期30-34,共5页
使用定理证明器COQ验证和分析PLC抢答器程序的一些性质,证明了原程序的所有可能状态中只有半数是可达状态,揭示了系统在可达状态之间的转移关系。基于这些性质,引入了逻辑自动机的概念作为对PLC程序行为完整抽象的描述。此外,在证明过程... 使用定理证明器COQ验证和分析PLC抢答器程序的一些性质,证明了原程序的所有可能状态中只有半数是可达状态,揭示了系统在可达状态之间的转移关系。基于这些性质,引入了逻辑自动机的概念作为对PLC程序行为完整抽象的描述。此外,在证明过程中,发现该程序中存在着一个很难通过现场测试发现的问题。 展开更多
关键词 可编程序控制器 PLC 嵌入式系统 COQ 定理证明
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Design and Implementation of Hand Gesture Detection System Using HM Model for Sign Language Recognition Development
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作者 Sharmin Akter Milu Azmath Fathima +2 位作者 Tanmay Talukder Inzamamul Islam Md. Ismail Siddiqi Emon 《Journal of Data Analysis and Information Processing》 2024年第2期139-150,共12页
Gesture detection is the primary and most significant step for sign language detection and sign language is the communication medium for people with speaking and hearing disabilities. This paper presents a novel metho... Gesture detection is the primary and most significant step for sign language detection and sign language is the communication medium for people with speaking and hearing disabilities. This paper presents a novel method for dynamic hand gesture detection using Hidden Markov Models (HMMs) where we detect different English alphabet letters by tracing hand movements. The process involves skin color-based segmentation for hand isolation in video frames, followed by morphological operations to enhance image trajectories. Our system employs hand tracking and trajectory smoothing techniques, such as the Kalman filter, to monitor hand movements and refine gesture paths. Quantized sequences are then analyzed using the Baum-Welch Re-estimation Algorithm, an HMM-based approach. A maximum likelihood classifier is used to identify the most probable letter from the test sequences. Our method demonstrates significant improvements over traditional recognition techniques in real-time, automatic hand gesture recognition, particularly in its ability to distinguish complex gestures. The experimental results confirm the effectiveness of our approach in enhancing gesture-based sign language detection to alleviate the barrier between the deaf and hard-of-hearing community and general people. 展开更多
关键词 Hand Gesture Recognition System
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