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An Improved LeNet-5 Model Based on Encrypted Data
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作者 Huanhuan Ni Yiliang Han +1 位作者 Xiaowei Duan Guohui Yang 《国际计算机前沿大会会议论文集》 2021年第2期166-178,共13页
In recent years,the problem of privacy leakage has attracted increasing attentions.Therefore,machine learning privacy protection becomes crucial research topic.In this paper,the Paillier homomorphic encryption algorit... In recent years,the problem of privacy leakage has attracted increasing attentions.Therefore,machine learning privacy protection becomes crucial research topic.In this paper,the Paillier homomorphic encryption algorithm is proposed to protect the privacy data.The original LeNet-5 convolutional neural network model was first improved.Then the activation function was modified and the C5 layer was removed to reduce the number of model parameters and improve the operation efficiency.Finally,by mapping the operation of each layer in the convolutional neural network from the plaintext domain to the ciphertext domain,an improved LeNet-5 model that can run on encrypted data was constructed.The purpose of using machine learning algorithmwas realized and privacywas ensured at the same time.The analysis shows that the model is feasible and the efficiency is improved. 展开更多
关键词 Paillier homomorphic encryption lenet-5 model Convolutional neural network Privacy protection
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IMPROVED SCHEME OF AXISYMMETRIC TYPHOON BOGUS MODEL AND ITS IMPACT ON NUMERICAL SIMULATION OF TYPHOON NOCKTEN (NO.0405)
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作者 袁金南 刘春霞 《Journal of Tropical Meteorology》 SCIE 2007年第2期181-184,共4页
There is distinct difference in the tangential wind profile between different typhoons in the western North Pacific. At present, only two parameters, maximum wind and radius of maximum wind, are used in NCAR-AFWA bogu... There is distinct difference in the tangential wind profile between different typhoons in the western North Pacific. At present, only two parameters, maximum wind and radius of maximum wind, are used in NCAR-AFWA bogus for MM5 mesoscale numerical model. As a result, sometimes the outer structure of typhoon cannot be described accurately. The tangential wind profile of NCAR-AFWA bogus is improved by introducing radii of 25.7 m/s and 15.4 m/s, and then the track and intensity of Typhoon Nockten (No.0425) are simulated. The results show that the simulations of track and intensity of typhoon both have been improved by simultaneously introducing the radii in the tangential wind profile of typhoon bogus. At the same time, there is improvement in the gale wind range of the typhoon simulated. 展开更多
关键词 improvement of tangential wind profile MM5 model typhoon Nockten (No.0425 simulations oftrack and intensity
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An improved typhoon monitoring model based on precipitable water vapor and pressure
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作者 Junyu Li Haojie Li +7 位作者 Lilong Liu Jiaqing Chen Yibin Yao Mingyun Hu Liangke Huang Fade Chen Tengxu Zhang Lv Zhou 《Geodesy and Geodynamics》 EI CSCD 2024年第3期276-290,共15页
The potential of monitoring the movement of typhoons using the precipitable water vapor(PWV) has been confirmed. However, monitoring the movement of typhoon is focused on PWV, making it difficult to describe the movem... The potential of monitoring the movement of typhoons using the precipitable water vapor(PWV) has been confirmed. However, monitoring the movement of typhoon is focused on PWV, making it difficult to describe the movement of a typhoon in detail minutely and resulting in insufficient accuracy. Hence,based on PWV and meteorological data, we propose an improved typhoon monitoring mode. First, the European Centre for Medium-Range Weather Forecasts Reanalysis 5-derived PWV(ERA5-PWV) and the Global Navigation Satellite System-derived PWV(GNSS-PWV) were compared with the reference radiosonde PWV(RS-PWV). Then, using the PWV and atmospheric parameters derived from ERA5, we discussed the anomalous variations of PWV, pressure(P), precipitation, and wind speed during different typhoons. Finally, we compiled a list of critical factors related to typhoon movement, PWV and P. We developed an improved multi-factor typhoon monitoring mode(IMTM) with different models(i.e.,IMTM-I and IMTM-II) in different cases with a higher density of GNSS observation or only Numerical Weather Prediction(NWP) data. The IMTM was evaluated through the reference movement speeds of HATO and Mangkhut from the China Meteorological Observatory Typhoon Network(CMOTN). The results show that the root mean square(RMS) of the IMTM-I is 1.26 km/h based on ERA5-P and ERA5-PWV,and the absolute bias values are mostly within 2 km/h. Compared with the models considering the single factor ERA5-P/ERA5-PWV, the RMS of the IMTM-I is improved by 26.3% and 38.5%, respectively. The IMTM-II model manifests a residual of only 0.35 km/h. Compared with the single-factor model based on GNSS-PWV/P, the residual of the IMTM-II model is reduced by 90.8% and 84.1%, respectively. These results propose that the typhoon movement monitoring approach combining PWV and P has evident advantages over the single-factor model and is expected to supplement traditional typhoon monitoring. 展开更多
关键词 TYPHOON GNSS/ERA5 PWV PRESSURE MONITORING improved model
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Comprehensive evaluation of 5G+smart distribution network based on combined weighting method-cloud model 被引量:9
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作者 Xiufan Ma Ying Wang +1 位作者 Zihao Liu Xiaoyu Feng 《Global Energy Interconnection》 EI CAS CSCD 2022年第6期675-691,共17页
With the large-scale application of 5G technology in smart distribution networks,the operation effects of distribution networks are not clear.Herein,we propose a comprehensive evaluation model of a 5G+smart distributi... With the large-scale application of 5G technology in smart distribution networks,the operation effects of distribution networks are not clear.Herein,we propose a comprehensive evaluation model of a 5G+smart distribution network based on the combination weighting and cloud model of the improved Fuzzy Analytic Hierarchy-Entropy Weight Method(FAHP-EWM).First,we establish comprehensive evaluation indexes of a 5G+smart distribution network from five dimensions:reliable operation,economic operation,efficient interaction,technological intelligence,and green emission reduction.Second,by introducing the principle of variance minimization,we propose a combined weighting method based on the improved FAHP-EWM to calculate the comprehensive weight,so as to reduce the defects of subjective arbitrariness and promote objectivity.Finally,a comprehensive evaluation model of 5G+smart distribution network based on cloud model is proposed by considering the uncertainty of distribution network node information and equipment status information.The example analysis indicates that the overall operation of the 5G+smart distribution network project is decent,and the weight value calculated by the combined weighting method is more reasonable and accurate than that calculated by the single weighting method,which verifies the effectiveness and rationality of the proposed evaluation method.Moreover,the proposed evaluation method has a certain guiding role for the large-scale application of 5G communication technology in smart distribution networks. 展开更多
关键词 5G+smart distribution network Comprehensive evaluation improved FAHP Variance minimization Normal cloud model
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基于改进LeNet-5的压印字符识别 被引量:2
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作者 汪志成 何坚强 +1 位作者 翁嘉鑫 苗荣 《计算机仿真》 北大核心 2022年第2期441-446,共6页
针对传统的图像识别算法在压印字符识别领域存在识别精度低、速度较慢的问题,提出了一种基于LeNet-5压印字符识别方法。与传统的LeNet-5不同,在文中网络各卷积层中采用小尺寸卷积核,以提取更多的特征并加快模型的训练速度;使用Inceptio... 针对传统的图像识别算法在压印字符识别领域存在识别精度低、速度较慢的问题,提出了一种基于LeNet-5压印字符识别方法。与传统的LeNet-5不同,在文中网络各卷积层中采用小尺寸卷积核,以提取更多的特征并加快模型的训练速度;使用InceptionV2卷积模块取代C5全连接层,可加深网络宽度,从而提高网络的识别精度;放弃全连接层F6,改用全局平均池化层,并且选用性能优越的Relu函数作为激活函数,以便减少训练参数,提高网络的训练速度。通过实验发现,文中模型的识别精度达到98.57%,与传统LeNet-5模型以及BP神经网络相比识别精度分别提高3%和4%,证明文中模型在压印字符的识别上拥有更大的优势。 展开更多
关键词 压印字符识别 改进模型 卷积神经网络 识别精度 收敛速度
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陕北生态治理对当地降水影响的数值模拟 被引量:11
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作者 郭建侠 杜继稳 郑有飞 《高原气象》 CSCD 北大核心 2005年第6期994-1001,共8页
利用中尺度模式MM5V3.5模拟了陕北地区两种植被改进方案对一次降雨过程的敏感性试验,结果表明,陕北植被改善后,能够使区域性降雨的雨带北移,平均降水量增加,降雨时间延长。另外,还分别从环流、大气稳定性、水汽条件、垂直运动等四个方... 利用中尺度模式MM5V3.5模拟了陕北地区两种植被改进方案对一次降雨过程的敏感性试验,结果表明,陕北植被改善后,能够使区域性降雨的雨带北移,平均降水量增加,降雨时间延长。另外,还分别从环流、大气稳定性、水汽条件、垂直运动等四个方面对上述变化的机理进行了分析,认为植被治理使背景环流的气旋性增强,低层大气不稳定范围向北增强扩展,高空风场辐合汇集的水汽增多,同时垂直上升运动有所增强,导致局地雨带北移、降雨量增加、降雨时间延长。模拟结果同时表明,下垫面生态治理的范围和规模越大,上述影响也越显著。 展开更多
关键词 植被治理方案 局地降水 MM5V3.5模式 敏感性 数值模拟 陕西 环流 大气稳定性 水汽条件 垂直运动
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航天器软件质量度量模型研究与应用 被引量:3
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作者 贺晓洋 金晟毅 +3 位作者 张杨 曹瑞强 苏若曦 彭兢 《航天器工程》 CSCD 北大核心 2022年第1期133-138,共6页
针对当前缺少通用的航天器软件产品质量度量方法、现有的方法难以表征和量化度量软件产品研制全过程的质量结果、难以根据质量度量结果开展针对性质量提升的问题,提出了一套通用的航天器软件产品研制过程质量度量模型。此模型对软件研... 针对当前缺少通用的航天器软件产品质量度量方法、现有的方法难以表征和量化度量软件产品研制全过程的质量结果、难以根据质量度量结果开展针对性质量提升的问题,提出了一套通用的航天器软件产品研制过程质量度量模型。此模型对软件研制过程质量要素9项要求和28条子要求进行了质量定义,设置了质量度量评分标准,基于评分结果可对软件产品开展针对性的质量提升工作。该模型首次应用于嫦娥五号探测器软件产品研制,有效地支撑了嫦娥五号任务的圆满成功,对于航天器型号软件产品研制过程具有参考价值和借鉴意义。 展开更多
关键词 航天器 软件 度量模型 质量提升 嫦娥五号探测器
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基于深度学习的板栗分级方法研究 被引量:2
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作者 王培福 孙一丹 +2 位作者 鹿子涵 王伟 陈晓峰 《湖北农业科学》 2022年第21期168-175,共8页
板栗品质分级对板栗产品的标准化和均一性有重要影响,精确的分类有助于板栗商品标准化,发挥出各等级板栗的最大价值。针对中国板栗分级分类大多依靠机器与人工,存在效率低、准确度低等问题,提出利用深度学习方法实现板栗分级分类的自动... 板栗品质分级对板栗产品的标准化和均一性有重要影响,精确的分类有助于板栗商品标准化,发挥出各等级板栗的最大价值。针对中国板栗分级分类大多依靠机器与人工,存在效率低、准确度低等问题,提出利用深度学习方法实现板栗分级分类的自动化与智能化。对经典卷积神经网络LeNet-5模型进行了改进,增加5层卷积层和2层池化层以加深网络,从而更准确地提取板栗特征,同时输入层修改为图像大小256×256的彩色图像;激活函数改进为Leaky ReLu,并加入Dropout算法缓解过拟合现象;使用Adam作为优化器对网络参数进行优化。将改进后的LeNet-5模型与初始LeNet-5模型、AlexNet和VGG16模型进行对比,发现改进后的LeNet-5模型在测试集上识别平均精确率为99.68%、准确率为99.34%、召回率为99.35%,优于其他3种模型,且识别1个样本用时仅0.19 s,改进后的LeNet-5模型可以实现对板栗良好的分级分类,满足工厂对板栗自动分级的需要。 展开更多
关键词 板栗分级 深度学习 卷积神经网络 改进lenet-5模型
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Study of Topological Structure of Vacuum by Lattice QCD
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作者 WANG Zi-Qing Lü Xiao-Fu WANG Fan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期535-538,共4页
Overlap fermions and improved 5Li cooling are compared, which exhibits that these two filter methods can produce similar structures. Then the overlap fermions and improved 5Li cooling are combined to calculate the top... Overlap fermions and improved 5Li cooling are compared, which exhibits that these two filter methods can produce similar structures. Then the overlap fermions and improved 5Li cooling are combined to calculate the topological charge and identify the structure of the vacuum. The results are consistent with instanton liquid model . 展开更多
关键词 overlap fermions improved 5Li cooling topological charge structure of the vacuum instanton liquid model
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羟乙基淀粉130/0.4改善大鼠心肌缺血再灌注损伤
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作者 孙海静 刘波 +4 位作者 邹最 王亚华 朱秋峰 袁红斌 石学银 《第二军医大学学报》 CAS CSCD 北大核心 2009年第8期947-949,共3页
目的:观察羟乙基淀粉(HES)130/0.4(万汶)对缺血再灌注(I/R)损伤心肌的干预作用,探讨其可能的作用机制。方法:24只SD大鼠随机均分为4组(n=6):假手术(S)组、缺血再灌注(IR)组、白蛋白-缺血再灌注(A-IR)组、HES-缺血再灌注(H-IR)组。后3组... 目的:观察羟乙基淀粉(HES)130/0.4(万汶)对缺血再灌注(I/R)损伤心肌的干预作用,探讨其可能的作用机制。方法:24只SD大鼠随机均分为4组(n=6):假手术(S)组、缺血再灌注(IR)组、白蛋白-缺血再灌注(A-IR)组、HES-缺血再灌注(H-IR)组。后3组建立在体大鼠心肌I/R模型,分别在缺血25min时股静脉持续泵入生理盐水、5%白蛋白或HES130/0.4,假手术组行开胸手术但不结扎左冠状动脉前降支。再灌注180min处死大鼠,取心肌组织观察病理学改变;处死前颈动脉采血ELISA法测定TNF-α、IL-1β浓度;测定心肌组织NF-κB活性。结果:H-IR组心肌组织损伤病理学改变较IR组、A-IR组减轻。IR组、A-IR组、H-IR组血清TNF-α、IL-1β水平和心肌NF-κB活性明显高于S组(P<0.05),但其中H-IR组血清TNF-α、IL-1β水平及心肌NF-κB活性上升程度不及IR组、A-IR组(P<0.05)。结论:羟乙基淀粉130/0.4能减轻缺血再灌注所致心肌病理损伤,可能与其抑制NF-κB的活性、减少促炎细胞因子的释放有关。 展开更多
关键词 心肌再灌注损伤 肿瘤坏死因子Α 白细胞介素1Β NF-κB 羟乙基淀粉
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应用微型机器人装置对难治性癫痫患者进行脑深部电极植入(英文) 被引量:5
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作者 Dorfer C Minchev G +6 位作者 Czech T Stefanits H Feucht M Pataraia E Baumgartner C Kronreif G Wolfsberger S 《中华神经外科疾病研究杂志》 CAS 2016年第4期308-308,共1页
关键词 癫痫 精确度 深度电极 机器人
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