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Frequent Itemset Mining of User’s Multi-Attribute under Local Differential Privacy

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Computers, Materials & Continua 2020年第10期65卷 369-385页

作者： haijiang Liu Lianwei Cui Xuebin Ma Celimuge Wu College of Computer Science Inner Mongolia UniversityHohhot010020China Inner Mongolia Big Data Development Authority Hohhot010020China Graduate School of Informatics and Engineering the University of Electro-CommunicationTokyo182-8585Japan

Frequent itemset mining is an essential problem in data mining and plays a key role in many data mining ***,users’personal privacy will be leaked in the mining *** recent years,application of local differential privacy protection models to mine frequent itemsets is a relatively reliable and secure protection *** differential privacy means that users first perturb the original data and then send these data to the aggregator,preventing the aggregator from revealing the user’s private *** propose a novel framework that implements frequent itemset mining under local differential privacy and is applicable to user’s *** main technique has bitmap encoding for converting the user’s original data into a binary *** also includes how to choose the best perturbation algorithm for varying user attributes,and uses the frequent pattern tree(FP-tree)algorithm to mine frequent ***,we incorporate the threshold random response(TRR)algorithm in the framework and compare it with the existing algorithms,and demonstrate that the TRR algorithm has higher accuracy for mining frequent itemsets.

关键词： Local differential privacy frequent itemset mining user’s multi-attribute

Physical model test study on shear strength characteristics of slope sliding surface in Nanfen open-pit mine

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International Journal of Mining Science and Technology 2020年第3期30卷 421-429页

作者： Zhigang Tao Yu Shu Xiaojie Yang Yanyan Peng Qihang Chen haijiang Zhang School of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing 100083China State Key Laboratory of Geomechanics and Deep Underground Engineering China University of Mining and Technology-BeijingBeijing 100083China School of Civil Engineering Shaoxing UniversityShaoxing 312000China Key Laboratory of Rock Mechanics and Geohazards of Zhejiang Province Shaoxing 312000China Zhejiang Collaborative Innovation Center for Prevention and Control of Mountain Geologic Hazards Shaoxing 312000China

A physical model for the footwall slope of Nanfen open-pit mine, China was established using a selfdeveloped deep geological engineering disaster model test system. A thermosensitive similar material,paraffin, was selected to simulate a weak structural plane in the slope to reproduce the landslide *** an experimental perspective, the variation trend of shear strength parameters of weak structural plane and the mechanical support characteristics of NPR(negative Poisson’s ratio) anchor cable under the condition of a large landslide deformation and failure were examined. The results of this model test showed that slope failure has four distinct stages:(1) soil compaction stage,(2) crack generation stage,(3) crack propagation stage, and(4) sliding plane transfixion stage. According to the test results, the rock mechanics parameters of weak surface in the footwall slope of Nanfen open-pit mine were *** cohesion is approximately 1.35×10~5 Pa, and the internal friction angle is approximately 6.33°.During slope failure, the NPR anchor cable experiences a large deformation but no damage occurs, indicating that the NPR anchor cable can be continuously monitored and reinforced during the deformation and failure of landslide. The stress characteristics of NPR anchor cables during the test are consistent with the monitoring results of Newtonian force at the landslide site, proving that NPR anchor cables are effective and reasonable in landslide monitoring and early warning.

关键词： Landslide Slope stability Structural plane Model test NPR anchor cable

黄河流域生态状况研究热点迁移与评价方法演变分析

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环境科学研究 2024年第1期37卷 63-72页

作者：赵旭谢慧钰李俊龙马煜刘海江贾世琪王业耀金小伟中国环境科学研究院北京100012 中国环境监测总站北京100012 北京师范大学水科学研究院北京100875

黄河流域是我国重要的生态安全屏障和经济活动区域,其生态环境直接关系到我国西北、华北地区的生态安全和可持续发展.为深入了解黄河流域生态状况研究的发展趋势、研究现状及研究热点,本文基于Web of Science核心合集数据库和中国期刊... 详细信息

黄河流域是我国重要的生态安全屏障和经济活动区域,其生态环境直接关系到我国西北、华北地区的生态安全和可持续发展.为深入了解黄河流域生态状况研究的发展趋势、研究现状及研究热点,本文基于Web of Science核心合集数据库和中国期刊全文数据库CNKI,检索了1981-2022年有关“黄河流域生态状况”的中英文文献,并对9400篇文献进行计量分析,据此整理出该研究领域的发展趋势和研究热点,对不同研究区域在研究内容上的差异进行分析.结果表明:黄河流域生态状况研究正处于高速发展阶段,热点研究内容包括生态环境、水资源和水土保持,热点研究对象包括生态系统、植被和水生生物,研究区域涵盖黄河全流域,影响黄河流域生态状况的重点研究因素包括人类活动、环境因子和时空因素.此外,不同研究区域所涉及的影响因素和研究对象具有差异性:从影响因素看,在黄河上、中、下游地区主要关注人类活动的影响,而在黄河三角洲和黄河河口地区重点关注水质和重金属等环境因子,在黄河全流域和黄河源区更注重时空因素的影响;从研究对象看,在黄河源区主要关注草地生态系统,而在黄河上、中、下游以及黄河三角洲地区主要集中在生态系统和植被方面,黄河河口的研究则更加侧重水生生物群落.根据以上研究结果,未来关于黄河流域及其特定河段的研究需要在选择研究对象和影响因素时考虑研究区域的特点,以确保研究的科学性;同时,统筹发展要求科研工作者不断更新研究方法和评价方法,将环境DNA、遥感等技术手段和综合的环境评价指标应用到流域生态状况评价研究中.

关键词：黄河流域生态状况评价方法文献计量

胜任力背景下住培师资角色冲突的表征、成因及建议

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现代养生 2024年第20期24卷 1595-1598页

作者：陈皓阳朱虹吴海江河北医科大学医教协同与医学教育研究中心

2013年12月，我国住院医师规范化培训（以下简称“住培”）全面启动，如今已基本完成制度建设，住培工作转向内涵质量提升环节。住培师资是提升住培质量的关键，高素质的师资队伍是住培发展的动力之源。胜任力源自美国，21世纪第三次医... 详细信息

2013年12月，我国住院医师规范化培训（以下简称“住培”）全面启动，如今已基本完成制度建设，住培工作转向内涵质量提升环节。住培师资是提升住培质量的关键，高素质的师资队伍是住培发展的动力之源。胜任力源自美国，21世纪第三次医学教育改革后，国外师资胜任力研究已具有理论基础及实践经验，但当前对住培师资的高胜任力要求和差异化角色使得住培师资面临角色冲突。本研究在角色理论视角下，基于胜任力背景，分析住培师资角色冲突的主要表征及其成因，在此基础上提出相关建议以期为完善相关政策，促进住培师资队伍建设可持续发展提供参考。

关键词：住培师资角色冲突角色理论

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基于零信任的“一机多网”云桌面设计

微型电脑应用 2024年第7期40卷 249-252页

作者：胡钧超黄海江张悦中国信息通信研究院信息管理中心北京100191 北京农村商业银行股份有限公司软件开发中心北京100029

企事业单位内通常使用传统PC作为办公桌面终端,安全性难以保证,容易发生文件泄露、网络攻击等安全事件,同时,系统间被要求网络隔离,导致办公桌需要放置多台PC,严重占用办公桌空间,浪费成本。针对上述问题,以云桌面作为桌面终端,融合零... 详细信息

企事业单位内通常使用传统PC作为办公桌面终端,安全性难以保证,容易发生文件泄露、网络攻击等安全事件,同时,系统间被要求网络隔离,导致办公桌需要放置多台PC,严重占用办公桌空间,浪费成本。针对上述问题,以云桌面作为桌面终端,融合零信任的安全理念,提出一种基于零信任的“一机多网”云桌面架构,此架构在传统云桌面的基础上,使用网络隔离切换器保证网络的传输安全以及强逻辑隔离,并将公网访问端口匿名化,进一步提升桌面终端安全性,同时有效减少传统办公PC的冗余。

关键词：办公终端零信任模型云桌面架构网络安全

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燃料电池空压机气磁悬浮系统的协同控制研究

机床与液压 2024年第9期52卷 73-80页

作者：竺志大韩雨哲孙帅柴青张帆寇海江杨坚曾励扬州大学机械工程学院江苏扬州225127

针对燃料电池空压机目前存在的驱动和支承问题,提出一种箔片动压轴承和动力磁轴承一体化的气磁悬浮型空压机。基于空压机的结构组成,建立空压机磁悬浮支承力、气悬浮支承力以及空压机转子动力学数学模型;基于燃料电池空压机转子系统动... 详细信息

针对燃料电池空压机目前存在的驱动和支承问题,提出一种箔片动压轴承和动力磁轴承一体化的气磁悬浮型空压机。基于空压机的结构组成,建立空压机磁悬浮支承力、气悬浮支承力以及空压机转子动力学数学模型;基于燃料电池空压机转子系统动力学模型的状态空间方程,设计抗干扰强的协同控制器,并对它进行了转速、驱动转矩、转子悬浮位移以及电磁调节力等关键物理量的仿真分析。结果表明:协同控制在响应、抗干扰以及鲁棒性方面的控制优于PID控制。基于协同控制和PID控制建立了控制实验平台,并对空压机转子的气磁悬浮进行分析,进一步验证了协同控制具有优良的控制效果和良好的控制性能。

关键词：燃料电池空压机气浮轴承动力磁轴承协同控制

基于改进DBNet-RNN的声级计读数识别方法

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计量学报 2024年第8期45卷 1191-1199页

作者：汪嘉祝海江王寅初何龙标杨平牛锋北京化工大学信息科学与技术学院北京100029 中国计量科学研究院北京100029

为提高声级计校准工作效率,提出了一种基于深度学习神经网络的声级计图像读数检测与识别方法。读数检测模型以DBNet为基础模型,将ShuffleNetV2作为主干网络,显著降低模型参数量;为提高读数区域检测精度,引入高效通道注意力ECA模块,提高... 详细信息

为提高声级计校准工作效率,提出了一种基于深度学习神经网络的声级计图像读数检测与识别方法。读数检测模型以DBNet为基础模型,将ShuffleNetV2作为主干网络,显著降低模型参数量;为提高读数区域检测精度,引入高效通道注意力ECA模块,提高网络对于通道特征的提取能力,优化后的模型在保持精度的同时参数量缩减为原来的15.4%,计算量缩减为原来的67.4%。读数识别模型以CRNN为基础模型,先加入批量规范化层,提高网络训练时的稳定性;然后,引入残差块替换原有的卷积块,提高了网络对于复杂特征的提取能力;将Dropout应用于网络中,提高网络的泛化能力;此外,在合成读数数据集上对读数识别模型进行预训练,有效增加了模型准确率。改进后的方法准确率达到了99.7%,相较原方法提高了2.4%。实验结果表明,该方法对声级计图像中存在的字体多样、光照不均、模糊等影响因素具有较强的鲁棒能力,对声级计图像中的读数具有较高的识别精度。

关键词：声学计量图像识别声级计 DBNet CRNN 注意力模块

Performance improvement for air-cooled open-cathode proton exchange membrane fuel cell with different design parameters of the gas diffusion layer

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Progress in Natural Science:Materials International 2020年第6期30卷 825-831页

作者： Chen Zhao Shuang Xing Wei Liu Ming Chen haijiang Wang Department of Mechanical and Energy Engineering Southern University of Science and Technology

Air-cooled open-cathode LTPEMFC(AO-LTPEMFC) has been developed as a new power source for the portable power supply. The effect of the gas diffusion layer(GDL) on AO-LTPEMFC operation in challenging ambient air conditions was investigated in the present study. The effect of the content of polytetrafluoroethylene(PTFE) on the substrate layer and microporous layer(MPL), the thickness of GDL and the pulse width modulation(PWM) of the fan on cell performance as well as the cathode outlet surface temperature distribution were investigated. The polarization curves, electrochemical impedance spectroscopy(EIS) and dynamic voltage test were used to correlate the structural characteristics of GDL with heat dissipation, oxygen transport and water management in AO-LTPEMFC. The results showed that GDL with appropriate PTFE content in the substrate layer and MPL could significantly optimize cell performance. In addition, the thickness of GDL also had a certain impact on the mass and heat transfer of the fuel cell, while the water management in GDL was affected by PWM of the fan, simultaneously. Combined with the practice process, the optimum values of the substrate layer PTFE content, MPL layer PTFE content and thickness of GDL were identified to be 10%, 40%, and 200 μm, respectively.

关键词： Gas diffusion layer (GDL) MPL Substrate layer PTFE content Thickness Air-cooled open cathode LT- PEMFC

Frequency-dependent rupture process,stress change,and seismogenic mechanism of the 25 April 2015 Nepal Gorkha M_w 7.8 earthquake

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Science China Earth Sciences 2017年第4期60卷 796-808页

作者： YIN JiuXun YAO HuaJian YANG HongFeng LIU Jing QIN WeiZe ZHANG haijiang Laboratory of Seismology and Physics of Earth 's Interior & School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Earth System Science Programme Faculty of Science Chinese University of Hong Kong Shatin NT Hong Kong 999077 China National Geophysical Observatory at Mengcheng University of Science and Technology of China Mengcheng 233500 China State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China

On 25 April 2015,an M_w 7.8 earthquake occurred on the Main Himalaya Thrust fault with a dip angle of^7° about77 km northwest of Kathmandu,*** Nepal Gorkha event is the largest one on the Himalayan thrust belt since *** we use the compressive sensing method in the frequency domain to track the seismic radiation and rupture process of this event using teleseismic P waves recorded by array stations in North *** also compute the distribution of static shear stress changes on the fault plane from a coseismic slip *** results indicate a dominant east-southeastward unilateral rupture process from the epicenter with an average rupture speed of ~3 km s^(-1).Coseismic radiation of this earthquake shows clear frequency-dependent *** lower frequency(0.05-0.3 Hz) radiation mainly originates from large coseismic slip regions with negative coseismic shear stress *** comparison,higher frequency(0.3-0.6 Hz) radiation appears to be from the down-dip part around the margin of large slip areas,which has been loaded and presents positive coseismic shear stress *** propose an asperity model to interpret this Nepal earthquake sequence and compare the frequency-dependent coseismic radiation with that in subduction *** frequency-dependent radiation indicates the depth-varying frictional properties on the plate interface of the Nepal section in the main Himalaya thrust system,similar to previous findings in oceanic subduction *** findings provide further evidence of the spatial correlation between changes of static stress status on the fault plane and the observed frequency-dependent coseismic radiation during large *** results show that the frequency-dependent coseismic radiation is not only found for megathrust earthquakes in the oceanic subduction environment,but also holds true for thrust events in the continental collision zone.

关键词： Pg wave Tomography Crust Velocity Anisotropy Volcano