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A chaotic hierarchical encryption/watermark embedding scheme for multi-medical images based on row-column confusion and closed-loop bi-directional diffusion
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作者 张哲祎 牟俊 +1 位作者 Santo Banerjee 曹颖鸿 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期228-237,共10页
Security during remote transmission has been an important concern for researchers in recent years.In this paper,a hierarchical encryption multi-image encryption scheme for people with different security levels is desi... Security during remote transmission has been an important concern for researchers in recent years.In this paper,a hierarchical encryption multi-image encryption scheme for people with different security levels is designed,and a multiimage encryption(MIE)algorithm with row and column confusion and closed-loop bi-directional diffusion is adopted in the paper.While ensuring secure communication of medical image information,people with different security levels have different levels of decryption keys,and differentiated visual effects can be obtained by using the strong sensitivity of chaotic keys.The highest security level can obtain decrypted images without watermarks,and at the same time,patient information and copyright attribution can be verified by obtaining watermark images.The experimental results show that the scheme is sufficiently secure as an MIE scheme with visualized differences and the encryption and decryption efficiency is significantly improved compared to other works. 展开更多
关键词 chaotic hierarchical encryption multi-medical image encryption differentiated visual effects row-column confusion closed-loop bi-directional diffusion transform domain watermark embedding
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Enhancing visual security: An image encryption scheme based on parallel compressive sensing and edge detection embedding
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作者 王一铭 黄树锋 +2 位作者 陈煌 杨健 蔡述庭 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期287-302,共16页
A novel image encryption scheme based on parallel compressive sensing and edge detection embedding technology is proposed to improve visual security. Firstly, the plain image is sparsely represented using the discrete... A novel image encryption scheme based on parallel compressive sensing and edge detection embedding technology is proposed to improve visual security. Firstly, the plain image is sparsely represented using the discrete wavelet transform.Then, the coefficient matrix is scrambled and compressed to obtain a size-reduced image using the Fisher–Yates shuffle and parallel compressive sensing. Subsequently, to increase the security of the proposed algorithm, the compressed image is re-encrypted through permutation and diffusion to obtain a noise-like secret image. Finally, an adaptive embedding method based on edge detection for different carrier images is proposed to generate a visually meaningful cipher image. To improve the plaintext sensitivity of the algorithm, the counter mode is combined with the hash function to generate keys for chaotic systems. Additionally, an effective permutation method is designed to scramble the pixels of the compressed image in the re-encryption stage. The simulation results and analyses demonstrate that the proposed algorithm performs well in terms of visual security and decryption quality. 展开更多
关键词 visual security image encryption parallel compressive sensing edge detection embedding
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A Linked List Encryption Scheme for Image Steganography without Embedding
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作者 Pengbiao Zhao Qi Zhong +3 位作者 Jingxue Chen Xiaopei Wang Zhen Qin Erqiang Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期331-352,共22页
Information steganography has received more and more attention from scholars nowadays,especially in the area of image steganography,which uses image content to transmit information and makes the existence of secret in... Information steganography has received more and more attention from scholars nowadays,especially in the area of image steganography,which uses image content to transmit information and makes the existence of secret information undetectable.To enhance concealment and security,the Steganography without Embedding(SWE)method has proven effective in avoiding image distortion resulting from cover modification.In this paper,a novel encrypted communication scheme for image SWE is proposed.It reconstructs the image into a multi-linked list structure consisting of numerous nodes,where each pixel is transformed into a single node with data and pointer domains.By employing a special addressing algorithm,the optimal linked list corresponding to the secret information can be identified.The receiver can restore the secretmessage fromthe received image using only the list header position information.The scheme is based on the concept of coverless steganography,eliminating the need for any modifications to the cover image.It boasts high concealment and security,along with a complete message restoration rate,making it resistant to steganalysis.Furthermore,this paper proposes linked-list construction schemeswithin theproposedframework,which caneffectively resist a variety of attacks,includingnoise attacks and image compression,demonstrating a certain degree of robustness.To validate the proposed framework,practical tests and comparisons are conducted using multiple datasets.The results affirm the framework’s commendable performance in terms of message reduction rate,hidden writing capacity,and robustness against diverse attacks. 展开更多
关键词 STEGANOGRAPHY ENCRYPTION steganography without embedding coverless steganography
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Identification of partial differential equations from noisy data with integrated knowledge discovery and embedding using evolutionary neural networks
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作者 Hanyu Zhou Haochen Li Yaomin Zhao 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第2期90-97,共8页
Identification of underlying partial differential equations(PDEs)for complex systems remains a formidable challenge.In the present study,a robust PDE identification method is proposed,demonstrating the ability to extr... Identification of underlying partial differential equations(PDEs)for complex systems remains a formidable challenge.In the present study,a robust PDE identification method is proposed,demonstrating the ability to extract accurate governing equations under noisy conditions without prior knowledge.Specifically,the proposed method combines gene expression programming,one type of evolutionary algorithm capable of generating unseen terms based solely on basic operators and functional terms,with symbolic regression neural networks.These networks are designed to represent explicit functional expressions and optimize them with data gradients.In particular,the specifically designed neural networks can be easily transformed to physical constraints for the training data,embedding the discovered PDEs to further optimize the metadata used for iterative PDE identification.The proposed method has been tested in four canonical PDE cases,validating its effectiveness without preliminary information and confirming its suitability for practical applications across various noise levels. 展开更多
关键词 PDE discovery Gene Expression Programming Deep Learning Knowledge embedding
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TCM-HIN2Vec:A strategy for uncovering biological basis of heart qi deficiency pattern based on network embedding and transcriptomic experiment
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作者 Lihong Diao Xinyi Fan +5 位作者 Jiang Yu Kai Huang Edouard C.Nice Chao Liu Dong Li Shuzhen Guo 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第3期264-274,共11页
Objective:To elucidate the biological basis of the heart qi deficiency(HQD)pattern,an in-depth understanding of which is essential for improving clinical herbal therapy.Methods: We predicted and characterized HQD patt... Objective:To elucidate the biological basis of the heart qi deficiency(HQD)pattern,an in-depth understanding of which is essential for improving clinical herbal therapy.Methods: We predicted and characterized HQD pattern genes using the new strategy,TCM-HIN2Vec,which involves heterogeneous network embedding and transcriptomic experiments.First,a heterogeneous network of traditional Chinese medicine(TCM)patterns was constructed using public databases.Next,we predicted HQD pattern genes using a heterogeneous network-embedding algorithm.We then analyzed the functional characteristics of HQD pattern genes using gene enrichment analysis and examined gene expression levels using RNA-seq.Finally,we identified TCM herbs that demonstrated enriched interactions with HQD pattern genes via herbal enrichment analysis.Results: Our TCM-HIN2Vec strategy revealed that candidate genes associated with HQD pattern were significantly enriched in energy metabolism,signal transduction pathways,and immune processes.Moreover,we found that these candidate genes were significantly differentially expressed in the transcriptional profile of mice model with heart failure with a qi deficiency pattern.Furthermore,herbal enrichment analysis identified TCM herbs that demonstrated enriched interactions with the top 10 candidate genes and could potentially serve as drug candidates for treating HQD.Conclusion: Our results suggested that TCM-HIN2Vec is capable of not only accurately identifying HQD pattern genes,but also deciphering the basis of HQD pattern.Furthermore our finding indicated that TCM-HIN2Vec may be further expanded to develop other patterns,leading to a new approach aimed at elucidating general TCM patterns and developing precision medicine. 展开更多
关键词 Qi deficiency pattern Heart failure Biological basis Network embedding Transcriptome
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Embedding-based approximate query for knowledge graph
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作者 Qiu Jingyi Zhang Duxi +5 位作者 Song Aibo Wang Honglin Zhang Tianbo Jin Jiahui Fang Xiaolin Li Yaqi 《Journal of Southeast University(English Edition)》 EI CAS 2024年第4期417-424,共8页
To solve the low efficiency of approximate queries caused by the large sizes of the knowledge graphs in the real world,an embedding-based approximate query method is proposed.First,the nodes in the query graph are cla... To solve the low efficiency of approximate queries caused by the large sizes of the knowledge graphs in the real world,an embedding-based approximate query method is proposed.First,the nodes in the query graph are classified according to the degrees of approximation required for different types of nodes.This classification transforms the query problem into three constraints,from which approximate information is extracted.Second,candidates are generated by calculating the similarity between embeddings.Finally,a deep neural network model is designed,incorporating a loss function based on the high-dimensional ellipsoidal diffusion distance.This model identifies the distance between nodes using their embeddings and constructs a score function.k nodes are returned as the query results.The results show that the proposed method can return both exact results and approximate matching results.On datasets DBLP(DataBase systems and Logic Programming)and FUA-S(Flight USA Airports-Sparse),this method exhibits superior performance in terms of precision and recall,returning results in 0.10 and 0.03 s,respectively.This indicates greater efficiency compared to PathSim and other comparative methods. 展开更多
关键词 approximate query knowledge graph embedding deep neural network
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Insider threat detection approach for tobacco industry based on heterogeneous graph embedding
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作者 季琦 LI Wei +2 位作者 PAN Bailin XUE Hongkai QIU Xiang 《High Technology Letters》 EI CAS 2024年第2期199-210,共12页
In the tobacco industry,insider employee attack is a thorny problem that is difficult to detect.To solve this issue,this paper proposes an insider threat detection method based on heterogeneous graph embedding.First,t... In the tobacco industry,insider employee attack is a thorny problem that is difficult to detect.To solve this issue,this paper proposes an insider threat detection method based on heterogeneous graph embedding.First,the interrelationships between logs are fully considered,and log entries are converted into heterogeneous graphs based on these relationships.Second,the heterogeneous graph embedding is adopted and each log entry is represented as a low-dimensional feature vector.Then,normal logs and malicious logs are classified into different clusters by clustering algorithm to identify malicious logs.Finally,the effectiveness and superiority of the method is verified through experiments on the CERT dataset.The experimental results show that this method has better performance compared to some baseline methods. 展开更多
关键词 insider threat detection advanced persistent threats graph construction heterogeneous graph embedding
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Thin-Shell Wormholes Admitting Conformal Motions in Spacetimes of Embedding Class One
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作者 Peter K. F. Kuhfittig 《International Journal of Astronomy and Astrophysics》 2024年第3期162-171,共10页
This paper discusses the feasibility of thin-shell wormholes in spacetimes of embedding class one admitting a one-parameter group of conformal motions. It is shown that the surface energy density σis positive, while ... This paper discusses the feasibility of thin-shell wormholes in spacetimes of embedding class one admitting a one-parameter group of conformal motions. It is shown that the surface energy density σis positive, while the surface pressure is negative, resulting in , thereby signaling a violation of the null energy condition, a necessary condition for holding a wormhole open. For a Morris-Thorne wormhole, matter that violates the null energy condition is referred to as “exotic”. For the thin-shell wormholes in this paper, however, the violation has a physical explanation since it is a direct consequence of the embedding theory in conjunction with the assumption of conformal symmetry. These properties avoid the need to hypothesize the existence of the highly problematical exotic matter. 展开更多
关键词 Thin-Shell Wormholes Conformal Symmetry embedding Class One Exotic Matter
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Optimisation of sparse deep autoencoders for dynamic network embedding
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作者 Huimei Tang Yutao Zhang +4 位作者 Lijia Ma Qiuzhen Lin Liping Huang Jianqiang Li Maoguo Gong 《CAAI Transactions on Intelligence Technology》 2024年第6期1361-1376,共16页
Network embedding(NE)tries to learn the potential properties of complex networks represented in a low-dimensional feature space.However,the existing deep learningbased NE methods are time-consuming as they need to tra... Network embedding(NE)tries to learn the potential properties of complex networks represented in a low-dimensional feature space.However,the existing deep learningbased NE methods are time-consuming as they need to train a dense architecture for deep neural networks with extensive unknown weight parameters.A sparse deep autoencoder(called SPDNE)for dynamic NE is proposed,aiming to learn the network structures while preserving the node evolution with a low computational complexity.SPDNE tries to use an optimal sparse architecture to replace the fully connected architecture in the deep autoencoder while maintaining the performance of these models in the dynamic NE.Then,an adaptive simulated algorithm to find the optimal sparse architecture for the deep autoencoder is proposed.The performance of SPDNE over three dynamical NE models(i.e.sparse architecture-based deep autoencoder method,DynGEM,and ElvDNE)is evaluated on three well-known benchmark networks and five real-world networks.The experimental results demonstrate that SPDNE can reduce about 70%of weight parameters of the architecture for the deep autoencoder during the training process while preserving the performance of these dynamical NE models.The results also show that SPDNE achieves the highest accuracy on 72 out of 96 edge prediction and network reconstruction tasks compared with the state-of-the-art dynamical NE algorithms. 展开更多
关键词 deep autoencoder dynamic networks low-dimensional feature space network embedding sparse structure
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联合体与共同体:应用型高校产教融合链式嵌入的两种重要方式 被引量:1
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作者 唐献玲 《教育理论与实践》 北大核心 2025年第3期14-18,共5页
在中国式教育现代化进程中,联合体与共同体是产教深度融合的重要范式,也是统筹推进教育科技人才进一步全面深化改革的关键载体。具体到应用型高校产教融合,基于人才链、创新链、产业链等多链条嵌入式发展视角,一方面,应从空间视角谋划... 在中国式教育现代化进程中,联合体与共同体是产教深度融合的重要范式,也是统筹推进教育科技人才进一步全面深化改革的关键载体。具体到应用型高校产教融合,基于人才链、创新链、产业链等多链条嵌入式发展视角,一方面,应从空间视角谋划推进区域协同多链互嵌,持续打造市域产教联合体,注重区域内嵌耦合,注重结构化协同配合,强化自适性产教服务;另一方面,应从分工视角提升组织逻辑运行的效能,以多链融合为架构、以统筹集约为路径、以创新创业为重心,持续打造行业产教共同体。在此基础上,聚焦产业集群成长曲线,实施伴生式嵌入;聚焦行业特色优势布局,实施专业化嵌入;聚焦资源良性循环运转,实施有组织嵌入,将联合体与共同体建设统一于新质生产力的链式发展要求,有效促进应用型高校产教融合发展。 展开更多
关键词 应用型高校 产教融合 联合体 共同体 内嵌耦合 多链融合
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基于k核分解的网络嵌入
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作者 张和平 张和贵 +3 位作者 谢晓尧 张太华 张思聪 喻国军 《计算机工程》 北大核心 2025年第2期139-148,共10页
近年来,网络嵌入技术受到了广大研究者的关注。不过大多数网络嵌入算法并未考虑到处于相同层级结构的节点间的结构相似性,这些节点在网络中通常具有相同的重要性。因此,提出一种基于网络层级结构的网络嵌入算法,称为KCNE。KCNE算法使用... 近年来,网络嵌入技术受到了广大研究者的关注。不过大多数网络嵌入算法并未考虑到处于相同层级结构的节点间的结构相似性,这些节点在网络中通常具有相同的重要性。因此,提出一种基于网络层级结构的网络嵌入算法,称为KCNE。KCNE算法使用网络节点间的层级结构信息来保持节点之间的结构相似性。该算法首先基于k核(k-core)分解方法将网络中的节点划分为不同的层级,并且使用定制的随机游走方法为每个节点生成游走序列,该序列可以有效捕获节点的一阶邻域及处于同层级中的高阶相似节点,随后将游走序列输入到Skip-gram模型中,使学习到的节点表示具有更好的区分性。基于多个真实数据集的实验结果表明,在链路预测和节点分类任务上,KCNE算法相比于8个基准算法中的次优算法性能提升最高分别约4%和5%。参数敏感性分析实验也表明了KCNE算法具有较好的鲁棒性。此外,该算法在运行效率方面均优于Role2Vec、RARE和GEMSEC算法。 展开更多
关键词 网络嵌入 结构相似性 随机游走 链路预测 节点分类
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一种基于STM32微控制器的电阻型湿度传感器校准系统设计
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作者 张鹏 殷家璇 +1 位作者 陶佰睿 李会 《传感技术学报》 北大核心 2025年第1期75-81,共7页
提出了一种基于STM32微控制器的电阻型湿度传感器校准系统,旨在提高传感器的工作性能,特别是要减少因湿滞和温度噪声等带来的误差。主要包括基于PID(比例微分积分)算法与PWM(脉宽调制)控制的饱和盐溶液相对湿度参考标准测试环境,干湿球... 提出了一种基于STM32微控制器的电阻型湿度传感器校准系统,旨在提高传感器的工作性能,特别是要减少因湿滞和温度噪声等带来的误差。主要包括基于PID(比例微分积分)算法与PWM(脉宽调制)控制的饱和盐溶液相对湿度参考标准测试环境,干湿球温度计湿度辅助测试定标系统,以及Buck(降压斩波)开关电源和LDO(低压差线性稳压)电路组成的电源电路、恒温电路、气压检测电路、电机驱动电路和输出显示电路等模块的软硬件设计。最后自制GO/ZnO/PCF(氧化石墨烯/氧化锌/植物纤维素薄膜)电阻型湿度传感器,把该电阻型湿度传感器放置在各相对湿度参考标准测试环境中实时记录传感器输出电阻值并对其进行校准测试,经多轮试验和数据处理,运用二分查找算法获取该传感器对应湿度数据。研究结果表明,所设计的校准系统可以将湿度传感器误差控制在±2%RH内,并在标准湿度测试环境中实现10 s内达到90%的稳定响应。此外,经过误差校准后,传感器恢复至新的稳定状态所需的时间不超过30 s。该校准系统具有低成本、简便操作和便携性等显著优势,具有重要的实用价值。 展开更多
关键词 湿度传感器 校准实验箱 嵌入式系统 PID
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嵌入式人工智能系统实验课程改革与探索
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作者 李磊 高学 +1 位作者 秦慧平 余翔宇 《实验室研究与探索》 北大核心 2025年第3期147-152,共6页
为适应人工智能技术的飞速发展,对嵌入式系统课程进行全面、深入的改革、优化并整合课程知识体系。在保障核心知识点教学的前提下,合理调整学时分配,为人工智能实验的顺利开展奠定了坚实基础。通过引入嵌入式人工智能实验项目,构建符合... 为适应人工智能技术的飞速发展,对嵌入式系统课程进行全面、深入的改革、优化并整合课程知识体系。在保障核心知识点教学的前提下,合理调整学时分配,为人工智能实验的顺利开展奠定了坚实基础。通过引入嵌入式人工智能实验项目,构建符合行业技术和人才培养需求的嵌入式人工智能课程体系。采用“基础+综合项目”的教学模式,既实现了嵌入式系统教学的循序渐进与系统性,又以学生兴趣为导向,有效培养学生的嵌入式工程实践能力,激发学生的主动性和创新动力。课程改革经验也可为其他院校提供参考。 展开更多
关键词 人工智能 嵌入式系统 教学改革 工程能力 创新能力
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面向变电站嵌入式设备的指针式仪表识别方法
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作者 胡欣 刘瑞峰 +3 位作者 肖剑 段承志 程鸿亮 罗诗伟 《电子测量与仪器学报》 北大核心 2025年第1期253-263,共11页
针对变电站嵌入式设备在识别指针式仪表时常面临实时性差以及小目标和密集目标场景漏检的问题,提出了一种基于YOLOv5s-BCGS的变电站指针式仪表识别模型。该模型以YOLOv5s为基础网络,首先在其网络颈部引入协调注意力机制,并将路径聚合网... 针对变电站嵌入式设备在识别指针式仪表时常面临实时性差以及小目标和密集目标场景漏检的问题,提出了一种基于YOLOv5s-BCGS的变电站指针式仪表识别模型。该模型以YOLOv5s为基础网络,首先在其网络颈部引入协调注意力机制,并将路径聚合网络替换为加权双向特征金字塔网络,以更好地融合特征图中的位置和细节信息,从而增强模型对目标位置和尺寸的敏感性。其次,原网络中的传统卷积被轻量化的幽灵卷积替代,既加快了推理速度,又减小了模型体积。最后,将原网络中的CIoU损失函数替换为SIoU损失函数,提高了模型训练速度并改善了远距离小目标的推理精度。实验结果表明,改进后的模型在自制变电站指针仪表数据集上的表现优于YOLOv5s,mAP0.5提高了2.2%,mAP0.75提高了3.8%,mAP0.5~0.95提高了6.7%,同时模型体积减少了34.07%。与常用的Faster R-CNN、YOLOv4-tiny、YOLOv7-tiny和YOLOv8n等模型相比,本模型在精度和速度上均具有明显优势,展现了良好的泛化能力和鲁棒性,且模型体积仅为18.0 MB,实现了轻量化部署。在PC和Jetson Xavier NX开发板上的推理速度分别为154.7 FPS和18.7 FPS,能够满足嵌入式设备在变电站指针仪表巡检中的实际工程需求。 展开更多
关键词 变电站 指针式仪表识别 轻量化 协调注意力机制 嵌入式设备
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基于改进YOLOv4的三维点云导盲系统设计
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作者 杜龙龙 陆学斌 罗孝 《计算机应用与软件》 北大核心 2025年第2期94-101,共8页
针对传统导盲系统存在抗环境干扰能力较低,识别准确率低等问题,提出一种基于YOLOv4的激光点云导盲系统。运用高精度激光扫描仪采集路况点云信息,将点云信息转换成包含特征信息的投影图像并建立路况数据集,搭建基于DARKNET的网络模型训... 针对传统导盲系统存在抗环境干扰能力较低,识别准确率低等问题,提出一种基于YOLOv4的激光点云导盲系统。运用高精度激光扫描仪采集路况点云信息,将点云信息转换成包含特征信息的投影图像并建立路况数据集,搭建基于DARKNET的网络模型训练框架识别复杂路况。采用K-means++算法改进YOLOv4模型中原有的聚类算法,提高模型多尺度检测的适应性。实验结果表明,系统识别复杂路况的平均精度为98.12%,与同类产品相比能够准确、稳定识别路况障碍。 展开更多
关键词 激光扫描 深度学习 YOLOv4 嵌入式应用 导盲系统
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基于PLC嵌入式技术的船舶航行自动控制系统设计
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作者 崔源 徐增勇 《舰船科学技术》 北大核心 2025年第6期158-161,共4页
船舶航行控制需适应复杂多变的航行环境扰动,PLC嵌入式技术具备强大的逻辑运算与适应能力,能够达到各种复杂场景的控制要求,为此,设计基于PLC嵌入式技术的船舶航行自动控制系统。通过系统的设备层实时采集船舶航行的位置、舵角、航向等... 船舶航行控制需适应复杂多变的航行环境扰动,PLC嵌入式技术具备强大的逻辑运算与适应能力,能够达到各种复杂场景的控制要求,为此,设计基于PLC嵌入式技术的船舶航行自动控制系统。通过系统的设备层实时采集船舶航行的位置、舵角、航向等数据,传入嵌入式控制层,该层调用其嵌入式微处理器存储与处理此类数据后,调用其所嵌入的BP神经网络PID控制器,以预设的船舶航行舵角为控制目标,对船舶的舵机实施控制,降低舵角偏差,达到船舶航行航向控制目的。结果显示,该系统可针对不同风力与风速航行环境下的船舶实现精准航行控制,控制后船舶在2种航行环境下的航行舵角几乎均能够与预设舵角相吻合,且均可按照预设航向航行,控制效果显著。 展开更多
关键词 PLC嵌入式技术 船舶航行 BP神经网络 PID控制器
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Locally linear embedding-based seismic attribute extraction and applications 被引量:5
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作者 刘杏芳 郑晓东 +2 位作者 徐光成 王玲 杨昊 《Applied Geophysics》 SCIE CSCD 2010年第4期365-375,400,401,共13页
How to extract optimal composite attributes from a variety of conventional seismic attributes to detect reservoir features is a reservoir predication key,which is usually solved by reducing dimensionality.Principle co... How to extract optimal composite attributes from a variety of conventional seismic attributes to detect reservoir features is a reservoir predication key,which is usually solved by reducing dimensionality.Principle component analysis(PCA) is the most widely-used linear dimensionality reduction method at present.However,the relationships between seismic attributes and reservoir features are non-linear,so seismic attribute dimensionality reduction based on linear transforms can't solve non-linear problems well,reducing reservoir prediction precision.As a new non-linear learning method,manifold learning supplies a new method for seismic attribute analysis.It can discover the intrinsic features and rules hidden in the data by computing low-dimensional,neighborhood-preserving embeddings of high-dimensional inputs.In this paper,we try to extract seismic attributes using locally linear embedding(LLE),realizing inter-horizon attributes dimensionality reduction of 3D seismic data first and discuss the optimization of its key parameters.Combining model analysis and case studies,we compare the dimensionality reduction and clustering effects of LLE and PCA,both of which indicate that LLE can retain the intrinsic structure of the inputs.The composite attributes and clustering results based on LLE better characterize the distribution of sedimentary facies,reservoir,and even reservoir fluids. 展开更多
关键词 attribute optimization dimensionality reduction locally linear embedding(LLE) manifold learning principle component analysis(PCA)
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嵌入式系统的需求描述综述
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作者 陈小红 刘少彬 金芝 《软件学报》 北大核心 2025年第1期27-46,共20页
随着嵌入式系统的广泛应用,其需求正变得越来越复杂,需求分析成为嵌入式系统开发的关键阶段,如何准确地建模和描述需求成为首要问题.系统地调研嵌入式系统的需求描述,并进行全面的比较分析,以便更深入地理解嵌入式系统需求的核心关注点... 随着嵌入式系统的广泛应用,其需求正变得越来越复杂,需求分析成为嵌入式系统开发的关键阶段,如何准确地建模和描述需求成为首要问题.系统地调研嵌入式系统的需求描述,并进行全面的比较分析,以便更深入地理解嵌入式系统需求的核心关注点.首先采用系统化文献综述方法,对1979年1月–2023年11月间发表的相关文献进行识别、筛选、汇总和分析.通过自动检索和滚雪球等检索过程,筛选出150篇与主题密切相关的文献,力求文献综述的全面性.其次,从需求描述关注点、需求描述维度、需求分析要素等方面,分析现有嵌入式需求描述语言的表达能力.最后,总结现有嵌入式系统软件需求描述所面临的挑战,并针对嵌入式软件智能合成任务,提出对嵌入式系统需求描述方法表达能力的要求. 展开更多
关键词 嵌入式系统 需求描述 需求描述语言 需求分析 系统需求
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基于嵌入式Android系统的实验教学设计与实践
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作者 张世娇 罗新民 杜清河 《实验科学与技术》 2025年第2期62-67,共6页
鉴于嵌入式系统在众多领域的广泛应用,该文将其与生活场景相结合,对嵌入式系统的实践教学进行了改革探索。设计了基于嵌入式Android系统的实验教学体系,全面覆盖了底层硬件操作、上层软件开发、软硬件协同设计以及综合实践项目等多个关... 鉴于嵌入式系统在众多领域的广泛应用,该文将其与生活场景相结合,对嵌入式系统的实践教学进行了改革探索。设计了基于嵌入式Android系统的实验教学体系,全面覆盖了底层硬件操作、上层软件开发、软硬件协同设计以及综合实践项目等多个关键层面。此教学体系不仅系统地传授了嵌入式系统软硬件开发的核心知识和技能,更通过一系列由浅入深的实验内容,有效强化了学生的动手实践能力,锤炼了其解决复杂工程问题的思维和方法,提升了学生的工程素养。该实验教学体系实用性强,对于培养具备创新能力和实践精神的嵌入式人才具有重要的推动作用。 展开更多
关键词 嵌入式系统 实践教学 综合设计 工程
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基于Cortex-M4内核的RT-Thread上下文切换机制剖析
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作者 徐丽华 王宜怀 奚圣鑫 《计算机应用与软件》 北大核心 2025年第1期213-216,302,共5页
RT-Thread是源码公开的国产嵌入式实时操作系统。基于Cortex-M4内核,对RT-Thread通过底层PendSV中断进行上下文切换的过程进行了剖析,从指令级别对上下文切换的实现机制进行了研究,为深入理解内核调度机制的实现提供了参考,也为RT-Threa... RT-Thread是源码公开的国产嵌入式实时操作系统。基于Cortex-M4内核,对RT-Thread通过底层PendSV中断进行上下文切换的过程进行了剖析,从指令级别对上下文切换的实现机制进行了研究,为深入理解内核调度机制的实现提供了参考,也为RT-Thread的应用与推广提供了技术基础。 展开更多
关键词 嵌入式实时操作系统 RT-THREAD 任务调度 上下文切换
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