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A Binary Vulnerability Similarity Detection Model Based on Deep Graph Matching
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作者 Yangzhi Zhang 《Journal of Electronic Research and Application》 2025年第5期291-298,共8页
To enhance network security,this study employs a deep graph matching model for vulnerability similarity detection.The model utilizes a Word Embedding layer to vectorize data words,an Image Embedding layer to vectorize... To enhance network security,this study employs a deep graph matching model for vulnerability similarity detection.The model utilizes a Word Embedding layer to vectorize data words,an Image Embedding layer to vectorize data graphs,and an LSTM layer to extract the associations between word and graph vectors.A Dropout layer is applied to randomly deactivate neurons in the LSTM layer,while a Softmax layer maps the LSTM analysis results.Finally,a fully connected layer outputs the detection results with a dimension of 1.Experimental results demonstrate that the AUC of the deep graph matching vulnerability similarity detection model is 0.9721,indicating good stability.The similarity scores for vulnerabilities such as memory leaks,buffer overflows,and targeted attacks are close to 1,showing significant similarity.In contrast,the similarity scores for vulnerabilities like out-of-bounds memory access and logical design flaws are less than 0.4,indicating good similarity detection performance.The model’s evaluation metrics are all above 97%,with high detection accuracy,which is beneficial for improving network security. 展开更多
关键词 Network security Word vectors Graph vector matrix Deep graph matching Vulnerability similarity
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A Fingerprint Minutiae Matching Method Based on Line Segment Vector 被引量:2
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作者 Jian-Wei Zhong Mei Xie 《Journal of Electronic Science and Technology of China》 2007年第3期260-263,共4页
Minutiae-based fingerprint matching is the most commonly used in an automatic fingerprint identification system. In this paper, we propose a minutia matching method based on line segment vector. This method uses all t... Minutiae-based fingerprint matching is the most commonly used in an automatic fingerprint identification system. In this paper, we propose a minutia matching method based on line segment vector. This method uses all the detected minutiae (the ridge ending and the ridge bifurcation) in a fingerprint image to create a set of new vectors (line segment vector). Using these vectors, we can determine a truer reference point more efficiently. In addition, this new minutiae vector can also increase the accuracy of the minutiae matching. By experiment on the public domain collections of fingerprint images fvc2004 DID set A and DB4 set A, the result shows that our algorithm can obtain an improved verification performance. 展开更多
关键词 FINGERPRINT line segment vector matching minutiae.
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Research on Vector Road Data Matching Method Based on Deep Learning
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作者 Lin Zhao Yanru Liu +3 位作者 Yuefeng Lu Ying Sun Jing Li Kaizhong Yao 《Journal of Applied Mathematics and Physics》 2023年第1期303-315,共13页
Most of the existing vector data matching methods use traditional feature geometry attribute features to match, however, many of the similarity indicators are not suitable for cross-scale data, resulting in less accur... Most of the existing vector data matching methods use traditional feature geometry attribute features to match, however, many of the similarity indicators are not suitable for cross-scale data, resulting in less accuracy in identifying objects. In order to solve this problem effectively, a deep learning model for vector road data matching is proposed based on siamese neural network and VGG16 convolutional neural network, and matching experiments are carried out. Experimental results show that the proposed vector road data matching model can achieve an accuracy of more than 90% under certain data support and threshold conditions. 展开更多
关键词 Deep Learning vector matching SIMILARITY VGG16 Siamese Network
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基于FFT-Matching Pursuit的心电身份识别算法研究 被引量:8
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作者 赵治栋 杨雷 陈甸甸 《传感技术学报》 CAS CSCD 北大核心 2013年第3期307-314,共8页
研究了心电信号在身份识别中的应用,提出了基于快速傅里叶变换的匹配追踪心电特征提取算法。在预处理阶段,对心电信号进行消噪、标准化和质量检测等预处理,有效去除了心电信号中的噪声和心率变异所带来的干扰。特征提取阶段,对心电模板... 研究了心电信号在身份识别中的应用,提出了基于快速傅里叶变换的匹配追踪心电特征提取算法。在预处理阶段,对心电信号进行消噪、标准化和质量检测等预处理,有效去除了心电信号中的噪声和心率变异所带来的干扰。特征提取阶段,对心电模板进行基于快速傅里叶变换的匹配追踪稀疏分解,原子的时频参数和投影值作为特征参数,然后构建支持向量机分类器,实现了身份识别。最后利用MIT-BIH的ST Change、PTB、QT等数据库测试了算法性能,获得了较高的识别率。 展开更多
关键词 心电 生物识别 匹配追踪 支持向量机
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FAST IMAGE ENCODING ALGORITHM BASED ON MEAN-MATCH CORRELATION VECTOR QUANTIZATION 被引量:1
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作者 徐润生 许晓鸣 张卫东 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第1期40-43,共4页
A mean-match correlation vector quantizer (MMCVQ) was presented for fast image encoding. In this algorithm, a sorted codebook is generated regarding the mean values of all codewords. During the encoding stage, high co... A mean-match correlation vector quantizer (MMCVQ) was presented for fast image encoding. In this algorithm, a sorted codebook is generated regarding the mean values of all codewords. During the encoding stage, high correlation of the adjacent image blocks is utilized, and a searching range is obtained in the sorted codebook according to the mean value of the current processing vector. In order to gain good performance, proper THd and NS are predefined on the basis of experimental experiences and additional distortion limitation. The expermental results show that the MMCVQ algorithm is much faster than the full-search VQ algorithm, and the encoding quality degradation of the proposed algorithm is only 0.3~0.4 dB compared to the full-search VQ. 展开更多
关键词 image coding vector quantization mean match method
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A new parallel algorithm for image matching based on entropy
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作者 董开坤 胡铭曾 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第4期399-402,共4页
Presents a new parallel image matching algorithm based on the concept of entropy feature vector and suitable to SIMD computer, which, in comparison with other algorithms, has the following advantages:(1)The spatial in... Presents a new parallel image matching algorithm based on the concept of entropy feature vector and suitable to SIMD computer, which, in comparison with other algorithms, has the following advantages:(1)The spatial information of an image is appropriately introduced into the definition of image entropy. (2) A large number of multiplication operations are eliminated, thus the algorithm is sped up. (3) The shortcoming of having to do global calculation in the first instance is overcome, and concludes the algorithm has very good locality and is suitable for parallel processing. 展开更多
关键词 image matching entropy feature vector parallel algorithm SIMD
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A Robust Template Matching Algorithm Based on Reducing Dimensions
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作者 Y. M. Fouda 《Journal of Signal and Information Processing》 2015年第2期109-122,共14页
Template matching is a fundamental problem in pattern recognition, which has wide applications, especially in industrial inspection. In this paper, we propose a 1-D template matching algorithm which is an alternative ... Template matching is a fundamental problem in pattern recognition, which has wide applications, especially in industrial inspection. In this paper, we propose a 1-D template matching algorithm which is an alternative for 2-D full search block matching algorithms. Our approach consists of three steps. In the first step the images are converted from 2-D into 1-D by summing up the intensity values of the image in two directions horizontal and vertical. In the second step, the template matching is performed among 1-D vectors using the similarity function sum of square difference. Finally, the decision will be taken based on the value of similarity function. Transformation template image and sub-images in the source image from 2-D grey level information into 1-D information vector reduce the dimensionality of the data and accelerate the computations. Experimental results show that the computational time of the proposed approach is faster and performance is better than three basic template matching methods. Moreover, our approach is robust to detect the target object with changes of illumination in the template also when the Gaussian noise added to the source image. 展开更多
关键词 Image Processing TEMPLATE matching vector SUM SUM of SQUARE DIFFERENCE
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Smart Clothing Fabric Color Matching with Reference to Popular Colors
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作者 ZHANG Yani ZHUANG Jianqiang +2 位作者 HUANG Rong DONG Aihua YUAN Haodong 《Journal of Donghua University(English Edition)》 CAS 2022年第4期317-324,共8页
Color economy and market fashion trend have an increasing impact on clothing fabric color matching.Therefore,a smart clothing fabric color matching system with reference to popular colors is designed to realize the di... Color economy and market fashion trend have an increasing impact on clothing fabric color matching.Therefore,a smart clothing fabric color matching system with reference to popular colors is designed to realize the diversification of clothing color matching,which includes a palette generation module and a clothing fabrics-palette color matching network(CF-PCN).Firstly,palette generation module generates palettes referring popular colors while maintains color styles of clothing fabrics.Secondly,CF-PCN generates color matching images containing color information of palettes.The experimental results show that the color matching system has a higher average pixel ratio of palette colors and contains more palette color information.It demonstrates that the system achieves color matching innovation referring popular colors while retaining color style of clothing brands and provides designers with appropriate color matching solutions. 展开更多
关键词 popular color clothing fabric color matching support vector machine(SVM) discrete particle swarm optimization algorithm generative adversarial network
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A semantic vector map-based approach for aircraft positioning in GNSS/GPS denied large-scale environment
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作者 Chenguang Ouyang Suxing Hu +6 位作者 Fengqi Long Shuai Shi Zhichao Yu Kaichun Zhao Zheng You Junyin Pi Bowen Xing 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期1-10,共10页
Accurate positioning is one of the essential requirements for numerous applications of remote sensing data,especially in the event of a noisy or unreliable satellite signal.Toward this end,we present a novel framework... Accurate positioning is one of the essential requirements for numerous applications of remote sensing data,especially in the event of a noisy or unreliable satellite signal.Toward this end,we present a novel framework for aircraft geo-localization in a large range that only requires a downward-facing monocular camera,an altimeter,a compass,and an open-source Vector Map(VMAP).The algorithm combines the matching and particle filter methods.Shape vector and correlation between two building contour vectors are defined,and a coarse-to-fine building vector matching(CFBVM)method is proposed in the matching stage,for which the original matching results are described by the Gaussian mixture model(GMM).Subsequently,an improved resampling strategy is designed to reduce computing expenses with a huge number of initial particles,and a credibility indicator is designed to avoid location mistakes in the particle filter stage.An experimental evaluation of the approach based on flight data is provided.On a flight at a height of 0.2 km over a flight distance of 2 km,the aircraft is geo-localized in a reference map of 11,025 km~2using 0.09 km~2aerial images without any prior information.The absolute localization error is less than 10 m. 展开更多
关键词 Large-scale positioning Building vector matching Improved particle filter GPS-Denied vector map
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Secure Transmission of Compressed Medical Image Sequences on Communication Networks Using Motion Vector Watermarking
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作者 Rafi Ullah Mohd Hilmi bin Hasan +1 位作者 Sultan Daud Khan Mussadiq Abdul Rahim 《Computers, Materials & Continua》 SCIE EI 2024年第3期3283-3301,共19页
Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all whil... Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all while upholding image quality.Moreover,an increasing number of hospitals are embracing cloud computing for patient data storage,necessitating meticulous scrutiny of server security and privacy protocols.Nevertheless,considering the widespread availability of multimedia tools,the preservation of digital data integrity surpasses the significance of compression alone.In response to this concern,we propose a secure storage and transmission solution for compressed medical image sequences,such as ultrasound images,utilizing a motion vector watermarking scheme.The watermark is generated employing an error-correcting code known as Bose-Chaudhuri-Hocquenghem(BCH)and is subsequently embedded into the compressed sequence via block-based motion vectors.In the process of watermark embedding,motion vectors are selected based on their magnitude and phase angle.When embedding watermarks,no specific spatial area,such as a region of interest(ROI),is used in the images.The embedding of watermark bits is dependent on motion vectors.Although reversible watermarking allows the restoration of the original image sequences,we use the irreversible watermarking method.The reason for this is that the use of reversible watermarks may impede the claims of ownership and legal rights.The restoration of original data or images may call into question ownership or other legal claims.The peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)serve as metrics for evaluating the watermarked image quality.Across all images,the PSNR value exceeds 46 dB,and the SSIM value exceeds 0.92.Experimental results substantiate the efficacy of the proposed technique in preserving data integrity. 展开更多
关键词 Block matching algorithm(BMA) compression full-search algorithm motion vectors ultrasound image sequence WATERMARKING
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人工智能算法在滑坡监测与预测技术中的研究与应用
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作者 程刚 吴勇飞 +1 位作者 曹德胜 吴亚熹 《地质科技通报》 北大核心 2025年第5期302-316,共15页
为减轻滑坡灾害风险,进一步保障区域可持续发展,开展有效的滑坡监测与预测研究具有重要的现实意义。通过研究滑坡监测与预测中的关键技术与方法,分析各类算法在滑坡监测与预测场景中的效率和精度,不断提升滑坡灾害防治水平。在特征提取... 为减轻滑坡灾害风险,进一步保障区域可持续发展,开展有效的滑坡监测与预测研究具有重要的现实意义。通过研究滑坡监测与预测中的关键技术与方法,分析各类算法在滑坡监测与预测场景中的效率和精度,不断提升滑坡灾害防治水平。在特征提取技术方面,对比分析了尺度不变特征变换(SIFT)、加速鲁棒特征(SURF)和自适应尺度不变特征变换(ASIFT)3种基于图像特征匹配算法的性能,其中ASIFT在匹配数量、精确率和召回率方面具有显著优势,尤其适用于准确性要求较高的复杂环境场景;在光流分析技术方面,探讨了基于Lucas-Kanade稀疏光流法和Horn-Schunck稠密光流法的应用效果,其中Lucas-Kanade稀疏光流法计算效率高,适合实时应用场景,但存在遗漏重要运动信息风险,Horn-Schunck稠密光流法能够提供全面的光流场信息,适用于环境复杂场景,但存在计算复杂度较高的不足,因而难以用于实时处理;在滑坡易发性预测方面,详细介绍了支持向量机(SVM)、决策树(DT)和随机森林(RF)等经典机器学习方法在滑坡预测中的应用优缺点,并重点研究了基于粒子群优化支持向量机(PSO-SVM)的模型性能,该模型通过优化超参数,显著提高了模型的分类准确度、泛化能力和预测精度。此外,通过引入Faster R-CNN模型,利用其先进的卷积神经网络架构,实现了复杂场景下滑坡事件的自动识别与分类,进一步提升了滑坡监测预警的效率和准确率。研究表明,ASIFT局部特征提取的精确率为0.84,Lucas-Kanade稀疏光流法的跟踪误差为0.12,PSO-SVM模型的均方根误差为0.52,Faster R-CNN模型在滑坡图像自动识别与分类方面的置信度可达0.98,综合性能较其他算法显著提升。综上所述,通过引入人工智能算法,结合多学科技术手段,全方面提升了滑坡监测与预测技术的效率和精度,研究成果为滑坡地质灾害防治提供了更有力的技术保障。 展开更多
关键词 人工智能算法 滑坡监测与预测 特征匹配 光流法 粒子群优化支持向量机(PSO-SVM)
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基于范数限制的更新向量同步扰动随机逼近算法的油藏自动历史拟合研究
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作者 曹静 杨军 《长江大学学报(自然科学版)》 2025年第2期97-103,共7页
油藏自动历史拟合可反演地质模型参数,拟合动态生产数据,为制定油藏生产方案提供关键信息。同步扰动随机逼近(SPSA)算法是自动历史拟合中应用最广泛的无梯度优化方法之一。但SPSA算法在求解优化问题时,当更新向量中的元素随着迭代次数... 油藏自动历史拟合可反演地质模型参数,拟合动态生产数据,为制定油藏生产方案提供关键信息。同步扰动随机逼近(SPSA)算法是自动历史拟合中应用最广泛的无梯度优化方法之一。但SPSA算法在求解优化问题时,当更新向量中的元素随着迭代次数增加而不断增大时,就会存在得到不稳定解的问题,导致目标函数无法收敛到最小值。针对该问题,提出一种基于具有范数限制的更新向量的同步扰动随机逼近(N-L SPSA)算法的自动历史拟合方法。该方法利用N-L SPSA算法不断迭代求解最优控制变量,并且在迭代过程中限制更新向量中元素的增大,避免得到不稳定解,保证最后得到最优油藏模型。与SPSA算法历史拟合结果对比,N-L SPSA算法的历史拟合结果在油藏模型静态参数反演、单井动态生产数据拟合时都更接近真实油藏,验证了该方法的有效性。 展开更多
关键词 同步扰动随机逼近 历史拟合 更新向量 范数限制
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基于多源数据的全球路网融合生产应用研究
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作者 林尚纬 杜晓 +6 位作者 张宏伟 吴晨琛 王艳东 周琦 朱玲 陈家阁 万咏涛 《地理空间信息》 2025年第1期90-94,122,共6页
基于OpenStreetMap (OSM)等开源道路数据,设计了一套多源矢量道路数据获取与预处理、要素匹配融合、名称翻译和属性挂接的生产加工技术流程,从多源路网几何信息和属性信息两个方面进行获取挖掘和补充。对乌拉圭进行道路融合生产应用的... 基于OpenStreetMap (OSM)等开源道路数据,设计了一套多源矢量道路数据获取与预处理、要素匹配融合、名称翻译和属性挂接的生产加工技术流程,从多源路网几何信息和属性信息两个方面进行获取挖掘和补充。对乌拉圭进行道路融合生产应用的结果表明,相较于初始OSM道路,匹配融合加工后的道路几何增长率约为20.31%,准确率约为97%,属性整体增长率约为4.64%,新增属性约为8.91%,准确率约为93%。相关研究成果已应用于境外地理信息资源建设等工程中,可为全球范围核心矢量要素数据产品制作和更新提供借鉴依据。 展开更多
关键词 自发地理信息 OSM 几何匹配 数据融合 矢量要素 路网
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月球可见光和SAR影像特征匹配方法比较研究 被引量:1
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作者 王晨旭 彭嫚 +2 位作者 谢彬 邸凯昌 芶盛 《遥感学报》 北大核心 2025年第2期389-401,共13页
多模态影像匹配方法已在地球多源遥感影像中获得了广泛应用,但月球多模态影像的匹配尚缺少对比性研究。为了实现高分辨率月球光学图像与SAR图像的高精度匹配,本文选择月球中纬度、低纬度、南极、北极等多个实验区影像,使用SIFT (Scale-I... 多模态影像匹配方法已在地球多源遥感影像中获得了广泛应用,但月球多模态影像的匹配尚缺少对比性研究。为了实现高分辨率月球光学图像与SAR图像的高精度匹配,本文选择月球中纬度、低纬度、南极、北极等多个实验区影像,使用SIFT (Scale-Invariant Feature Transform)、基于区域的CFOG (Channel Features of Orientated Gradients)、HOPC (Histogram of Orientated Phase Congruency)和基于结构特征的RIFT (Radiation-variation Insensitive Feature Transform)、 HAPCG (Histogram of Absolute Phase Consistency Gradients)、 HOWP(Histogram of the Orientation of the Weighted Phase descriptor)和深度学习SuperGlue、 LoFTR (Local Feature TRansformer)共8种特征匹配算法进行实验比较研究,通过正确匹配点数、均方根误差、重复率和覆盖度4种指标对匹配结果进行比较分析。结果表明,HAPCG算法使用了各向异性滤波并结合绝对相位方向梯度直方图构成特征向量,匹配效果最优。LoFTR算子使用了自注意层和互注意层机制,对纹理贫乏的月球影像效果次之。HOWP和SuperGlue匹配效果居中。CFOG、HOPC和RIFT效果最差。SIFT未能实现匹配。匹配点的分布和成像光照条件、影像重叠区域相关,中低纬度地区匹配效果优于南北极地区。对HAPCG匹配结果的Stokes第一参数进行了统计分析,雨海和高地实验区的匹配点的散射特性参数的平均值高于南极北极实验区,和地形特征相符。散点图显示出HAPCG匹配点对应的Stokes第一参数和光学影像灰度值存在相关性,证明了HAPCG对非线性辐射差异较大的月球光学影像和SAR影像匹配的稳健性。本研究为月球光学影像和SAR影像匹配方法的选择提供参考,有助于月球多源数据的应用。 展开更多
关键词 月球 多模态匹配 SAR影像 光学影像 Stokes参数
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基于同名实体匹配的控制点自动提取方法
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作者 杨庆生 潘瑜春 潘雨青 《计算机仿真》 2025年第5期513-519,共7页
针对图像与矢量地图的匹配过程中人工选取地面控制点工作量大、实时性差的问题,提出一种利用同名实体特征点转换为匹配控制点的方法。首先对图像进行色彩分割、边缘和直线检测,并对图像中的轮廓分类得到实体对象,然后与矢量地图进行同... 针对图像与矢量地图的匹配过程中人工选取地面控制点工作量大、实时性差的问题,提出一种利用同名实体特征点转换为匹配控制点的方法。首先对图像进行色彩分割、边缘和直线检测,并对图像中的轮廓分类得到实体对象,然后与矢量地图进行同名实体匹配,最后从同名实体中提取特征点转换为控制点。仿真结果表明,上述方法对不同参数获取的图像均能提取到有效实体及空间分布均匀性较好的控制点,基于所选控制点对图像进行多项式变换,其结果与人工选点的RMSE值相近,具有良好的匹配精度。 展开更多
关键词 视频图像 矢量地图 同名实体 图像匹配 控制点
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结合参数辨识和牛顿插值的并网逆变器延时补偿策略
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作者 闫军 胡云鹏 +3 位作者 刘鉴钧 都成刚 姜伟基 李博通 《现代电力》 北大核心 2025年第3期443-450,共8页
随着电力系统“双高”的发展趋势,可再生能源经由并网逆变器接入电网的比例不断增加,而并网逆变器引入的控制延时会改变并网逆变器阻抗特性,使并网系统存在谐振风险,危及电网安全。工程现场并网逆变器内部控制延时参数因保密而未知。针... 随着电力系统“双高”的发展趋势,可再生能源经由并网逆变器接入电网的比例不断增加,而并网逆变器引入的控制延时会改变并网逆变器阻抗特性,使并网系统存在谐振风险,危及电网安全。工程现场并网逆变器内部控制延时参数因保密而未知。针对以上问题,提出一种结合参数辨识和牛顿插值的并网逆变器延时补偿策略。首先利用Loewner矩阵改进矢量匹配,拟合并网逆变器阻抗传递函数,由此实现并网逆变器控制延时参数的正确辨识。并基于此,给出基于牛顿插值的补偿延时方法。通过补偿控制系统中所需要的延时时间,对逆变器阻抗进行重塑,从而有效抑制系统谐振。最后,通过仿真验证所提方法的正确性与有效性。 展开更多
关键词 并网逆变器 控制延时 矢量匹配 牛顿插值
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基于隐马尔科夫模型的中文分词优化方法探讨
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作者 张富 张璇 《测绘科学》 北大核心 2025年第2期43-48,共6页
针对目前在自然语言处理中存在中文语义歧义性的问题,该文提出了一种通过优化中文分词来消除语义歧义的研究方法,在正向最大匹配算法基础上,通过Word2Vec模型将分词文本转换为词向量,并与相对应字符输入至隐马尔科夫模型,以此优化中文... 针对目前在自然语言处理中存在中文语义歧义性的问题,该文提出了一种通过优化中文分词来消除语义歧义的研究方法,在正向最大匹配算法基础上,通过Word2Vec模型将分词文本转换为词向量,并与相对应字符输入至隐马尔科夫模型,以此优化中文分词的准确性和稳定性。将Word2Vec词向量融入隐马尔科夫模型中,显著提高了中文分词的准确率,一定程度上能有效消除部分中文语义歧义问题,提升自然语言处理效果。本方法在中文自然语言处理中的应用具有重要意义,能够为复杂文本的分词和歧义消除提供有效支持。 展开更多
关键词 自然语言处理 中文分词 分词组合 正向最大匹配 Word2Vec词向量模型 隐马尔可夫模型
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基于四元数BFM的图像Copy-Move篡改检测算法
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作者 赵杰 景雪 李亚文 《信息技术》 2025年第6期40-45,共6页
有效地检测和防止图像的篡改和伪造,成为数字图像取证领域的研究热点之一。Copy-Move篡改是一种常见的图像篡改方式。文中提出了一种基于四元数贝塞尔傅里叶矩(BFM)的篡改检测算法。首先将图像进行重叠分块,然后计算各分块的四元数贝塞... 有效地检测和防止图像的篡改和伪造,成为数字图像取证领域的研究热点之一。Copy-Move篡改是一种常见的图像篡改方式。文中提出了一种基于四元数贝塞尔傅里叶矩(BFM)的篡改检测算法。首先将图像进行重叠分块,然后计算各分块的四元数贝塞尔傅里叶矩来作为每个分块的特征向量,并使用改进的PatchMatch算法对特征向量进行初步匹配,再去除误匹配块,得到最终篡改区域。实验仿真结果表明,该算法可以有效地检测图像中的Copy-Move篡改,并且对JPEG压缩、旋转、缩放和加噪等篡改区域后处理操作具有较好的鲁棒性。 展开更多
关键词 篡改 贝塞尔傅里叶矩 四元数 特征向量 特征匹配
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矢量网络分析仪与史密斯圆图的应用
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作者 张海 《电声技术》 2025年第5期133-136,共4页
随着射频技术和微波技术在无线通信、卫星通信、雷达及医学成像等领域的广泛应用,射频系统的设计和优化愈发依赖精确的测试工具。矢量网络分析仪(Vector Network Analyzer,VNA)和史密斯圆图是射频测试中的关键工具,二者结合有助于系统... 随着射频技术和微波技术在无线通信、卫星通信、雷达及医学成像等领域的广泛应用,射频系统的设计和优化愈发依赖精确的测试工具。矢量网络分析仪(Vector Network Analyzer,VNA)和史密斯圆图是射频测试中的关键工具,二者结合有助于系统性能评估、阻抗匹配和反射损耗优化。探讨VNA的工作原理、测量方法与应用领域,分析史密斯圆图的概念与应用,并阐述二者的结合应用。通过案例应用,验证其在射频系统调试和维护中的重要性。 展开更多
关键词 矢量网络分析仪(VNA) 史密斯圆图 射频测量 反射系数 阻抗匹配 S参数 驻波比 射频系统优化
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Design of Ballistic Consistency Based on Least Squares Support Vector Machine and Particle Swarm Optimization
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作者 张宇宸 杜忠华 戴炜 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第5期549-554,共6页
In order to improve the firing efficiency of projectiles,it is required to use the universal firing table for gun weapon system equipped with a variety of projectiles.Moreover,the foundation of sharing the universal f... In order to improve the firing efficiency of projectiles,it is required to use the universal firing table for gun weapon system equipped with a variety of projectiles.Moreover,the foundation of sharing the universal firing table is the ballistic matching for two types of projectiles.Therefore,a method is proposed in the process of designing new type of projectile.The least squares support vector machine is utilized to build the ballistic trajectory model of the original projectile,thus it is viable to compare the two trajectories.Then the particle swarm optimization is applied to find the combination of trajectory parameters which meet the criterion of ballistic matching best.Finally,examples show the proposed method is valid and feasible. 展开更多
关键词 ballistic matching least squares support vector machine particle swarm optimization curve fitting
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