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Classified VPN Network Traffic Flow Using Time Related to Artificial Neural Network
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作者 Saad Abdalla Agaili Mohamed Sefer Kurnaz 《Computers, Materials & Continua》 SCIE EI 2024年第7期819-841,共23页
VPNs are vital for safeguarding communication routes in the continually changing cybersecurity world.However,increasing network attack complexity and variety require increasingly advanced algorithms to recognize and c... VPNs are vital for safeguarding communication routes in the continually changing cybersecurity world.However,increasing network attack complexity and variety require increasingly advanced algorithms to recognize and categorizeVPNnetwork data.We present a novelVPNnetwork traffic flowclassificationmethod utilizing Artificial Neural Networks(ANN).This paper aims to provide a reliable system that can identify a virtual private network(VPN)traffic fromintrusion attempts,data exfiltration,and denial-of-service assaults.We compile a broad dataset of labeled VPN traffic flows from various apps and usage patterns.Next,we create an ANN architecture that can handle encrypted communication and distinguish benign from dangerous actions.To effectively process and categorize encrypted packets,the neural network model has input,hidden,and output layers.We use advanced feature extraction approaches to improve the ANN’s classification accuracy by leveraging network traffic’s statistical and behavioral properties.We also use cutting-edge optimizationmethods to optimize network characteristics and performance.The suggested ANN-based categorization method is extensively tested and analyzed.Results show the model effectively classifies VPN traffic types.We also show that our ANN-based technique outperforms other approaches in precision,recall,and F1-score with 98.79%accuracy.This study improves VPN security and protects against new cyberthreats.Classifying VPNtraffic flows effectively helps enterprises protect sensitive data,maintain network integrity,and respond quickly to security problems.This study advances network security and lays the groundwork for ANN-based cybersecurity solutions. 展开更多
关键词 VPN network traffic flow ANN classification intrusion detection data exfiltration encrypted traffic feature extraction network security
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浅谈3ds Max中Thinking Particles和Particle Flow的区别 被引量:2
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作者 魏玲 《数字技术与应用》 2014年第11期215-216,共2页
Thinking Particles和Particle Flow是3ds Max中两大粒子系统,是动画师制作动画特效的两大利器,本文分别介绍了Thinking Particles和Particle Flow两个粒子系统的优缺点,并且从两个不同的方面讲述了两者的区别。
关键词 THINKING PARTICLES PARTICLE flow 3ds max 粒子系统
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Extraction Kinetics of Lanthanum in Chloride Medium by Bifunctional Ionic Liquid [A336][CA-12] Using a Constant Interfacial Cell with Laminar Flow 被引量:3
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作者 杨华玲 陈继 +3 位作者 王威 崔红敏 张冬丽 刘郁 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第10期1174-1177,共4页
The extraction kinetics of La(III) from aqueous chloride solutions into n-heptane solutions of bifunctional ionic liquid extractant [A336][CA-12](tricaprylmethylammonium sec-octylphenoxy acetic acid) was investigated ... The extraction kinetics of La(III) from aqueous chloride solutions into n-heptane solutions of bifunctional ionic liquid extractant [A336][CA-12](tricaprylmethylammonium sec-octylphenoxy acetic acid) was investigated using a constant interfacial cell with laminar flow. The effects of stirring speed, temperature and specific interfacial area on the extraction rate were examined. The results indicate that mass transfer kinetics of La(III) is a mixed-controlled process influenced by interfacial reaction. On the basis of mass transfer kinetic results in the extraction of La(III) by [A336][CA-12], the extraction rate equation of La(III) is proposed in terms of pseudo-firstorder constants, which is supported by the measured thermodynamic equations. The mass-transfer kinetic model deduced from the rate controlling step is adequate to interpret the experimental data qualitatively. 展开更多
关键词 extraction kinetics BIFUNCTIONAL ionic liquid CONSTANT INTERFACIAL CELL with LAMINAR flow
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Convective heat transfer of water flow in intersected rock fractures for enhanced geothermal extraction 被引量:3
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作者 Yuedu Chen Zhihong Zhao Huan Peng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第1期108-122,共15页
Numerous intersected rock fractures constitute the fracture network in enhanced geothermal systems.The complicated convective heat transfer behavior in intersected fractures is critical to the heat recovery in fractur... Numerous intersected rock fractures constitute the fracture network in enhanced geothermal systems.The complicated convective heat transfer behavior in intersected fractures is critical to the heat recovery in fractured geothermal reservoirs.A series of three-dimensional intersected fracture models is constructed to perform the flow-through heat transfer simulations.The geometry effects of dead-end fractures(DEFs)on the heat transfer are evaluated in terms of intersected angles,apertures,lengths,and the connectivity.The results indicate that annular streamlines appear in the rough DEF and cause an ellipse distribution of the cold front.Compared to plate DEFs,the fluid flow in the rough DEF enhances the heat transfer.Both the increment of outlet water temperatureΔToutand the ratio of heat production Qrpresent the largest at the intersected angle of 90°while decline with the decrease of the intersected angle between the main flow fracture(MFF)and the DEFs.The extension of the length of intersected DEFs is beneficial to heat production while enhancing its aperture is not needed.Solely increasing the number of intersected DEFs induces a little increase of heat extraction,and more significant heat production can be obtained through connecting these DEFs with the MFF forming the flow network. 展开更多
关键词 Heat transfer Fracture intersection Fluid flow Rough fracture Geothermal extraction
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Comparison of Co-Current and Counter-Current Flow Fields on Extraction Performance in Micro-Channels
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作者 Subramaniam Pushpavanam Benny Malengier 《Advances in Chemical Engineering and Science》 2012年第2期309-320,共12页
Several applications such as liquid-liquid extraction in micro-fluidic devices are concerned with the flow of two immiscible liquid phases. The commonly observed flow regimes in these systems are slug-flow and stratif... Several applications such as liquid-liquid extraction in micro-fluidic devices are concerned with the flow of two immiscible liquid phases. The commonly observed flow regimes in these systems are slug-flow and stratified flow. The latter regime in micro-channels has the inherent advantage that separation of the two liquids at the exit is efficient. Recently extraction in a stratified counter-current flow has been studied experimentally and it has been shown to be more efficient than co-current flow. An analytical as well as a numerical method to determine the steady-state solution of the corresponding convection-diffusion equation for the two flow-fields is presented. It is shown that the counter-current process is superior to the co-current process for the same set of parameters and operating conditions. A simplified model is proposed to analyse the process when diffusion in the transverse direction is not rate limiting. Different approaches to determining mass transfer coefficient are compared. The concept of log mean temperature difference used in design of heat exchangers is extended to describe mass transfer in the system. 展开更多
关键词 PLUG flow DIFFUSION extraction CO-CURRENT COUNTER-CURRENT
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粒子巨匠——3ds max粒子系统Particle Flow
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《CG杂志》 北大核心 2004年第2期60-63,共4页
3ds max粒子的发展历史中出现过几款很具有影响力的综合性粒子插件,像早期的Digimation的Particle Studio,Cebas的Matterwaves,Next Limit公司开发的独立粒子系统RealFlow和后来出现的Thinking Particles。
关键词 3ds max 粒子 PARTICLE flow 插件
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粒子巨匠 2——3ds max 粒子系统 Particle Flow
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《CG杂志》 北大核心 2004年第3期58-61,共4页
在上期的[讲经堂]里,我为大家讲解了一些应用Particle Flow的例子,陆陆续续的也收到一些朋友的来信,看来大家对PF的热情还是蛮高的,刚好最近Allan Mckay又发布了新的测试.所以这期带给大家的仍然是3ds max6的粒子系统Particle Flow。
关键词 3ds max 粒子系统 PARTICLE flow 效果展示图 实现过程
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Analyzing History Quality for Routing Purposes in Opportunistic Network Using Max-Flow
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作者 Muhammad Arshad Islam Marcel Waldvogel 《Wireless Engineering and Technology》 2012年第3期132-141,共10页
Most of the existing opportunistic network routing protocols are based on some type of utility function that is directly or indirectly dependent on the past behavior of devices. The past behavior or history of a devic... Most of the existing opportunistic network routing protocols are based on some type of utility function that is directly or indirectly dependent on the past behavior of devices. The past behavior or history of a device is usually referred to as contacts that the device had in the past. Whatever may be the metric of history, most of these routing protocols work on the realistic premise that node mobility is not truly random. In contrast, there are several oracles based methods where such oracles assist these methods to gain access to information that is unrealistic in the real world. Although, such oracles are unrealistic, they can help to understand the nature and behavior of underlying networks. In this paper, we have analyzed the gap between these two extremes. We have performed max-flow computations on three different opportunistic networks and then compared the results by performing max-flow computations on history generated by the respective networks. We have found that the correctness of the history based prediction of history is dependent on the dense nature of the underlying network. Moreover, the history based prediction can deliver correct paths but cannot guarantee their absolute reliability. 展开更多
关键词 OPPORTUNISTIC NETWORKS Delay TOLERANT NETWORKS ROUTING Protocols max-flow Simulation Modified Dijk-Stra Algorithm
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基于孤立森林算法的弹性光网络异常流量自动识别方法 被引量:3
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作者 李橙 何孙秦 +1 位作者 卫星 张国华 《激光杂志》 CAS 北大核心 2024年第1期179-183,共5页
弹性光网络流量传输受到时间波动导致异常,为了提高网络传输稳定性,提出基于孤立森林算法的弹性光网络异常流量自动识别算法。根据流量的异常分布特征和正常数据的差异性进行波谱密度检测,构建弹性光网络流量的谱特征提取模型,通过低通... 弹性光网络流量传输受到时间波动导致异常,为了提高网络传输稳定性,提出基于孤立森林算法的弹性光网络异常流量自动识别算法。根据流量的异常分布特征和正常数据的差异性进行波谱密度检测,构建弹性光网络流量的谱特征提取模型,通过低通滤波器卷积向量重组,实现对异常流量的谱特征筛选,采用孤立森林算法实现对网络流量异常检测的自适应寻优控制,结合多维空间结构重组方法实现对弹性光网络异常流量检测和识别。结果表明,漏检率及误检率较低,分别为3.16%,1.03%。检测用时较少,仅用16秒。在进行检测时,外部入侵率未超过1%,抗扰性较强。 展开更多
关键词 孤立森林算法 弹性光网络 异常流量 谱特征提取
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基于车载点云的道路三维实景建模方法研究 被引量:1
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作者 徐辛超 丁雪 《测绘与空间地理信息》 2024年第2期17-20,共4页
传统的基础测绘存在组织管理固化、服务模式落后、产品形式单一等问题,在新型基础测绘体系下形成了全要素三维实景模型这一成果。本文探讨基于车载点云进行城市道路三维实景建模方法研究,并以某城市主干路为试验对象,对道路及道路两侧... 传统的基础测绘存在组织管理固化、服务模式落后、产品形式单一等问题,在新型基础测绘体系下形成了全要素三维实景模型这一成果。本文探讨基于车载点云进行城市道路三维实景建模方法研究,并以某城市主干路为试验对象,对道路及道路两侧部件点云数据进行矢量化得到道路全要素地形数据,以部件点云数据为参考结合外业调绘尺寸用3ds Max软件制作道路部件模板库,并结合点云数据和矢量数据对各类要素进行单体化,最后将道路模型和部件模型融合。结果表明,基于车载点云数据构建的城市道路全要素实景模型不仅可以保证场景的完整性和真实性,还减少了作业时间和成本,实现了各类模型之间的无缝结合,制作完成的模型精度也能满足项目精度要求。 展开更多
关键词 车载点云 矢量提取 3ds max 道路建模 部件建模
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基于UNet3+生成对抗网络的视频异常检测 被引量:1
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作者 陈景霞 林文涛 +1 位作者 龙旻翔 张鹏伟 《计算机工程与设计》 北大核心 2024年第3期777-784,共8页
为解决传统视频异常检测方法在不同场景下多尺度特征提取不完全的问题,提出两种方法:一种是用于简单场景的基于UNet3+的生成对抗网络方法(简称U3P^(2)),另一种是用于复杂场景的基于UNet++的生成对抗网络方法(简称UP^(3))。两种方法分别... 为解决传统视频异常检测方法在不同场景下多尺度特征提取不完全的问题,提出两种方法:一种是用于简单场景的基于UNet3+的生成对抗网络方法(简称U3P^(2)),另一种是用于复杂场景的基于UNet++的生成对抗网络方法(简称UP^(3))。两种方法分别对连续输入的视频帧生成预测,引入多种损失函数和光流模型学习其外观与运动信息,通过计算AUC进行性能评估。U3P^(2)方法以6.3 M参数量在Ped2数据集的AUC提升约0.6%,而UP^(3)方法在Avenue数据集的AUC提升约0.8%,验证其能够有效应对不同场景下的异常检测任务。 展开更多
关键词 生成对抗网络 视频异常检测 U型卷积网络 全尺度跳跃连接 密集跳跃连接 光流模型 多尺度特征提取
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一种剃须刀外壳注塑模具设计 被引量:1
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作者 白松 《模具技术》 2024年第1期14-19,共6页
以一种剃须刀外壳的设计为基础,通过分析产品结构特征,设计了一模两腔,动、定模多个斜向复杂抽芯的结构,并运用模流分析软件模拟产品的填充、保压、冷却过程。发现该模具结构设计合理,开合模动作准确可靠,多个斜向抽芯之间无干涉,产品... 以一种剃须刀外壳的设计为基础,通过分析产品结构特征,设计了一模两腔,动、定模多个斜向复杂抽芯的结构,并运用模流分析软件模拟产品的填充、保压、冷却过程。发现该模具结构设计合理,开合模动作准确可靠,多个斜向抽芯之间无干涉,产品成型表面质量较好,可以达到客户的需求。模具结构新颖,可以为同类设计提供借鉴。 展开更多
关键词 剃须刀外壳 复杂抽芯 模流分析 模具设计
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非结构化网格下海洋流场的特征提取与种子点选取算法
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作者 李忠伟 宫凯旋 +1 位作者 李永 刘格格 《计算机工程》 CSCD 北大核心 2024年第1期320-328,共9页
对于非结构化网格流场数据,现有研究存在不能定位流场中临界点的具体位置、无法对临界点精细分类以及缺乏适用于非结构化网格的种子点选取算法等问题。针对上述问题,基于非结构化网格流场数据,分别在临界点提取和种子点选取方法上进行... 对于非结构化网格流场数据,现有研究存在不能定位流场中临界点的具体位置、无法对临界点精细分类以及缺乏适用于非结构化网格的种子点选取算法等问题。针对上述问题,基于非结构化网格流场数据,分别在临界点提取和种子点选取方法上进行改进创新。提出非结构化网格中临界点的定位及分类方法,通过庞加莱指数法判断存在临界点的三角网格。构造质心迭代法定位临界点在网格中的准确位置,并设计三角网格内雅克比矩阵的构造方法,将临界点精细分类。基于非结构化网格提出基于最大得分和网格密度的种子点选取算法,先比较相邻格点的标量值大小来计算每个格点的得分,形成“最大得分”标量场,再按照网格密度动态设置阈值,将得分大于阈值的格点选为种子点,接着以种子点为起始点生成流线,生成的流线可以表达出流场的关键特征与全局信息。基于多个海域流场数据的实验结果表明,临界点分类的准确率可达99%以上,证明了临界点提取算法的准确性以及种子点选取算法对提升流场可视化效果的有效性。 展开更多
关键词 非结构化三角网格 临界点提取 种子点选取 最大得分 流场可视化
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在线流动-蒸馏法分析药食同源食品中二氧化硫残留量
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作者 薛峰 《中国食品添加剂》 CAS 2024年第11期201-207,共7页
采用在线流动-蒸馏法测定分析百合、芡实药食同源食品中二氧化硫残留量,采用碱性溶液震荡提取,流动注射法分析了多批次百合、芡实药食同源的二氧化硫残留量,在0.5~10.0 mg/L浓度范围内线性良好,相关系数R2=0.9991,平均回收率97.3%,RSD为... 采用在线流动-蒸馏法测定分析百合、芡实药食同源食品中二氧化硫残留量,采用碱性溶液震荡提取,流动注射法分析了多批次百合、芡实药食同源的二氧化硫残留量,在0.5~10.0 mg/L浓度范围内线性良好,相关系数R2=0.9991,平均回收率97.3%,RSD为2.1%~4.6%,检出限为1.0 mg/kg,定量限为3.0 mg/kg。实验结果与传统蒸馏滴定法比较,两种方法结果没有显著性差异。该方法提取方式简单、耗时短、准确度高,适用于大批量药食同源食品分析检测。 展开更多
关键词 在线流动 蒸馏 药食同源 二氧化硫残留量 震荡提取
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贵州省地热流体资源可开采资源量研究
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作者 易世友 李强 +1 位作者 陈刚 吉勒克补子 《地下水》 2024年第1期85-88,共4页
综合贵州省地热研究相关成果资料,分析贵州省地热流体资源赋存条件及地热水资源分布特征,以此为基础将贵州省划分为110个地热资源量估算区,参照省内地热流体资源主要集中在断裂带周边的实际特点,采用设计布井法、泉(井)流量统计法和比... 综合贵州省地热研究相关成果资料,分析贵州省地热流体资源赋存条件及地热水资源分布特征,以此为基础将贵州省划分为110个地热资源量估算区,参照省内地热流体资源主要集中在断裂带周边的实际特点,采用设计布井法、泉(井)流量统计法和比拟法对贵州地热流体可开采资源量进行估算。结果表明:贵州地热流体资源的形成和分布,受省内地质构造特点及其在全国构造所处部位的控制,地热资源成因类型可划分为沉积盆地传导型地热储和隆起山地断裂对流型地热储,总体热储温度一般小于90℃,为低温地热资源;估算出贵州省地热流体可开采资源总量为23190.37 m^(3)/a,其中设计布井法估算的资源量为15926.22 m^(3)/a,天然温泉可开采资源量1183.34 m^(3)/a,地热井可开采资源量6080.80 m^(3)/a,总热能906933.97 Kw,年开采累计可利用热能量476.68×10^(8)MJ。所估算的地热流体可采资源量可为贵州省地热资源的勘查开发规划提供参考依据。 展开更多
关键词 地热流体 可开采资源量 设计布井法 泉(井)流量统计法 贵州省
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优先提锂湿法工艺回收废旧磷酸铁锂电池
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作者 罗佳 刘勇 +3 位作者 周洋 崔俊葳 陈雨阳 周成乾 《湖南有色金属》 CAS 2024年第5期30-33,65,共5页
文章详细介绍了一种优先提锂湿法回收碳酸锂的工艺流程,先用碱除铝,再酸浸分离磷酸铁,除杂后沉锂,工艺流程简化、试剂消耗量小、锂浸出选择性较高,工艺经济效益相对更好,可以为磷酸铁锂电池回收企业提供一种工艺流程简化、试剂消耗量小... 文章详细介绍了一种优先提锂湿法回收碳酸锂的工艺流程,先用碱除铝,再酸浸分离磷酸铁,除杂后沉锂,工艺流程简化、试剂消耗量小、锂浸出选择性较高,工艺经济效益相对更好,可以为磷酸铁锂电池回收企业提供一种工艺流程简化、试剂消耗量小、锂浸出选择性较高、工艺经济效益相对更好的工艺技术路线。 展开更多
关键词 废旧磷酸铁锂电池回收 优先提锂 电池级碳酸锂 工艺流程
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Kinetics of cerium(Ⅳ) and fluoride extraction from sulfuric solutions using bifunctional ionic liquid extractant(Bif-ILE)[A336][P204] 被引量:7
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作者 杨华玲 陈继 +3 位作者 张冬丽 王威 崔红敏 刘郁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1937-1945,共9页
The extraction kinetics of Ce(Ⅳ) and Ce(Ⅳ)-F^- mixture systems from sulfuric solutions to n-heptane solution containing Bif-ILE[A336][P204]([trialkylmethylammonium][di-2-ethylhewanxylphosphinate]) with a const... The extraction kinetics of Ce(Ⅳ) and Ce(Ⅳ)-F^- mixture systems from sulfuric solutions to n-heptane solution containing Bif-ILE[A336][P204]([trialkylmethylammonium][di-2-ethylhewanxylphosphinate]) with a constant interfacial area cell with laminar flow were studied,just to elucidate the extraction mechanism and the mass transfer models.The data were analyzed in terms of pseudo-first-order constants.The effects of stirring speed,specific interfacial area and temperature on the extraction rate in both systems were discussed,suggesting that the extractions were mixed bulk phases-interfacial control process.Supported by the experimental data,the corresponding rate equations for Ce(Ⅳ) extraction system and Ce(Ⅳ)-F^- mixture extraction system were obtained.The experimental results indicated the rate-controlling step.The kinetics model was deduced from the rate-controlling step and consistent with the rate equation. 展开更多
关键词 Ce(Ⅳ)-F--system Bif-ILE kinetics model extraction kinetics constant interfacial area cell with laminar flow
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InSAR相位解缠最大流/最小割权值改进算法
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作者 高延东 贾义琨 +4 位作者 李世金 陈宇 李怀展 郑南山 张书毕 《测绘学报》 EI CSCD 北大核心 2024年第4期644-652,共9页
InSAR已经在高精度DEM反演中得到了广泛应用,相位解缠技术是影响DEM获取精度的关键步骤之一,然而大梯度变化区域一直是影响解缠结果精度的核心问题。针对该问题,本文提出一种基于势函数改进权值的最大流/最小割相位解缠算法。首先,针对P... InSAR已经在高精度DEM反演中得到了广泛应用,相位解缠技术是影响DEM获取精度的关键步骤之一,然而大梯度变化区域一直是影响解缠结果精度的核心问题。针对该问题,本文提出一种基于势函数改进权值的最大流/最小割相位解缠算法。首先,针对PUMA模型权值设置不合理的问题进行研究,利用外部已有DEM获取相位梯度变化的先验信息,将窗口最大绝对相位梯度值代入相应的势函数公式中获取权值;然后,通过对势函数权值的设置进行阈值调节,解决由于势函数权值设置不合理导致PUMA势函数无法发挥作用引起的解缠错误问题,进而提高大梯度变化区域相位解缠精度;最后,通过仿真数据和真实TanDEM-X InSAR数据对本文算法进行验证,并与已有方法进行对比。结果表明,仿真数据中本文算法可以提高至少44.93%的解缠精度,真实数据中在大梯度变化区域,本文算法较已有算法可以获得更大范围的有效解缠结果。 展开更多
关键词 INSAR 势函数 最大流/最小割 相位解缠
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高压氧联合银杏叶提取物治疗老年血管性痴呆疗效观察 被引量:3
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作者 刘莉莉 陈艳芳 王晓宇 《新乡医学院学报》 CAS 2024年第5期477-481,共5页
目的探讨高压氧联合银杏叶提取物治疗老年血管性痴呆的临床疗效。方法选择2019年1月至2022年12月在郑州市第九人民医院就诊的132例老年血管性痴呆患者为研究对象,采用随机数字表法将患者分为观察组和对照组,每组66例。2组患者均给予常... 目的探讨高压氧联合银杏叶提取物治疗老年血管性痴呆的临床疗效。方法选择2019年1月至2022年12月在郑州市第九人民医院就诊的132例老年血管性痴呆患者为研究对象,采用随机数字表法将患者分为观察组和对照组,每组66例。2组患者均给予常规治疗,在此基础上,对照组患者给予高压氧治疗,每日1次;观察组患者给予高压氧联合银杏叶提取物治疗,每日1次;2组患者均连续治疗1个月。分别于治疗前后采用蒙特利尔认知评估量表(MoCA)和Barthel指数评估2组患者的认知功能和日常生活活动能力,并依据MoCA评分和Barthel指数评估2组患者治疗后的临床疗效。分别于治疗前后采用经颅多普勒超声仪检测2组患者大脑前动脉、大脑后动脉、大脑中动脉及椎动脉平均血流速度等脑血流动力学指标。结果治疗前2组患者MoCA评分及Barthel指数比较差异无统计学意义(P>0.05)。治疗后,2组患者MoCA评分及Barthel指数均高于治疗前(P<0.05),且观察组患者的MoCA评分及Barthel指数显著高于对照组(P<0.05)。治疗后,对照组和观察组患者总有效率分别为84.85%(56/66)和95.45%(63/66),观察组患者总有效率显著高于对照组(χ^(2)=4.181,P<0.05)。治疗前2组患者大脑前动脉、大脑后动脉、大脑中动脉及椎动脉平均血流速度比较差异无统计学意义(P>0.05)。治疗后,2组患者大脑前动脉、大脑后动脉、大脑中动脉及椎动脉平均血流速度大于治疗前(P<0.05),且观察组患者大脑前动脉、大脑后动脉、大脑中动脉及椎动脉平均血流速度大于对照组(P<0.05)。治疗期间对照组和观察组患者总不良反应发生率分别为16.67%(11/66)、18.18%(12/66),2组患者总不良反应发生率比较差异无统计学意义(χ^(2)=0.218,P>0.05)。结论高压氧联合银杏叶提取物可更显著地改善老年血管性痴呆患者脑血流状态和认知功能障碍,提高患者日常生活活动能力,总体疗效好,且安全性高。 展开更多
关键词 血管性痴呆 高压氧 银杏叶提取物 认知功能 脑血流速度
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A data-driven model of drop size prediction based on artificial neural networks using small-scale data sets 被引量:1
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作者 Bo Wang Han Zhou +3 位作者 Shan Jing Qiang Zheng Wenjie Lan Shaowei Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期71-83,共13页
An artificial neural network(ANN)method is introduced to predict drop size in two kinds of pulsed columns with small-scale data sets.After training,the deviation between calculate and experimental results are 3.8%and ... An artificial neural network(ANN)method is introduced to predict drop size in two kinds of pulsed columns with small-scale data sets.After training,the deviation between calculate and experimental results are 3.8%and 9.3%,respectively.Through ANN model,the influence of interfacial tension and pulsation intensity on the droplet diameter has been developed.Droplet size gradually increases with the increase of interfacial tension,and decreases with the increase of pulse intensity.It can be seen that the accuracy of ANN model in predicting droplet size outside the training set range is reach the same level as the accuracy of correlation obtained based on experiments within this range.For two kinds of columns,the drop size prediction deviations of ANN model are 9.6%and 18.5%and the deviations in correlations are 11%and 15%. 展开更多
关键词 Artificial neural network Drop size Solvent extraction Pulsed column Two-phase flow HYDRODYNAMICS
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