Network traffic identification in packet sampling environment

With the rapid growth of network bandwidth,traffic identification is currently an important challenge for network management and security.In recent years,packet sampling has been widely used in most network management systems.In this paper,in order to improve the accuracy of network traffic identification,sampled NetFlow data is applied to traffic identification,and the impact of packet sampling on the accuracy of the identification method is studied.This study includes feature selection,a metric correlation analysis for the application behavior,and a traffic identification algorithm.Theoretical analysis and experimental results show that the significance of behavior characteristics becomes lower in the packet sampling environment.Meanwhile,in this paper,the correlation analysis results in different trends according to different features.However,as long as the flow number meets the statistical requirement,the feature selection and the correlation degree will be independent of the sampling ratio.While in a high sampling ratio,where the effective information would be less,the identification accuracy is much lower than the unsampled packets.Finally,in order to improve the accuracy of the identification,we propose a Deep Belief Networks Application Identification(DBNAI)method,which can achieve better classification performance than other state-of-the-art methods.

Modelling of vehicle interaction behavior during discretionary lane-changing preparation process on freeway

In order to increase the accuracy of microscopic traffic flow simulation,two acceleration models are presented to simulate car-following behaviors of the lane-changing vehicle and following putative vehicle during the discretionary lanechanging preparation( DLCP) process, respectively. The proposed acceleration models can reflect vehicle interaction characteristics. Samples used for describing the starting point and the ending point of DLCP are extracted from a real NGSIM vehicle trajectory data set. The acceleration model for a lanechanging vehicle is supposed to be a linear acceleration model.The acceleration model for the following putative vehicle is constructed by referring to the optimal velocity model,in which optimal velocity is defined as a linear function of the velocity of putative leading vehicle. Similar calibration,a hypothesis test and parameter sensitivity analysis were conducted on the acceleration model of the lane-changing vehicle and following putative vehicle,respectively. The validation results of the two proposed models suggest that the training and testing errors are acceptable compared with similar works on calibrations for car following models. The parameter sensitivity analysis shows that the subtle observed error does not lead to severe variations of car-following behaviors of the lane-changing vehicle and following putative vehicle.

Torque effect on vibration behavior of high-speed train gearbox under internal and external excitations

The high-speed train transmission system,experiencing both the internal excitation originating from gear meshing and the external excitation originating from the wheel-rail interaction,exhibits complex dynamic behavior in the actual service environment.This paper focuses on the gearbox in the high-speed train to carry out the bench test,in which various operat-ing conditions(torques and rotation speeds)were set up and the excitation condition covering both internal and external was created.Acceleration responses on multiple positions of the gearbox were acquired in the test and the vibration behavior of the gearbox was studied.Meanwhile,a stochastic excitation modal test was also carried out on the test bench under different torques,and the modal parameter of the gearbox was identified.Finally,the sweep frequency response of the gearbox under gear meshing excitation was analyzed through dynamic modeling.The results showed that the torque has an attenuating effect on the amplitude of gear meshing frequency on the gearbox,and the effect of external excitation on the gearbox vibration cannot be ignored,especially under the rated operating condition.It was also found that the torque affects the modal param-eter of the gearbox significantly.The torque has a great effect on both the gear meshing stiffness and the bearing stiffness in the transmission system,which is the inherent reason for the changed modal characteristics observed in the modal test and affects the vibration behavior of the gearbox consequently.

Identification of traffic object's motion behavior based on track

To extract the track parameters of a traffic object in traffic video and identify its motion behavior,a new method is proposed based on CamShift(Continuously Adaptive Mean Shift)and HMM(Hidden Markov Model).First,an object entering the video scene is located and tracked by the CamShift based algorithm,then its track parameters are obtained.Next,the track parameters are processed to form the observation sequence of HMM,and the motion behavior modeling and probability evaluation are implemented based on HMM.At last,the behavior identification and behavior statistics of the tracked traffic object in video are achieved.Experiments show that this method can be used to sort and recognize the motion behavior of the traffic object by its corresponding behavior track,and to do some statistics or corresponding process schemes.

Abnormal driving behavior identification based on direction and position offsets

Abnormal driving behavior identification( ADBI) has become a research hotspot because of its significance in driver assistance systems. However,current methods still have some limitations in terms of accuracy and reliability under severe traffic scenes. This paper proposes a new ADBI method based on direction and position offsets,where a two-factor identification strategy is proposed to improve the accuracy and reliability of ADBI. Self-adaptive edge detection based on Sobel operator is used to extract edge information of lanes. In order to enhance the efficiency and reliability of lane detection,an improved lane detection algorithm is proposed,where a Hough transform based on local search scope is employed to quickly detect the lane,and a validation scheme based on priori information is proposed to further verify the detected lane. Experimental results under various complex road conditions demonstrate the validity of the proposed ADBI.

Parameter identification of hysteretic model of rubber-bearing based on sequential nonlinear least-square estimation

In order to evaluate the nonlinear performance and the possible damage to rubber-bearings （RBs） during their normal operation or under strong earthquakes, a simplified Bouc-Wen model is used to describe the nonlinear hysteretic behavior of RBs in this paper, which has the advantages of being smooth-varying and physically motivated. Further, based on the results from experimental tests performed by using a particular type of RB （GZN 110） under different excitation scenarios, including white noise and several earthquakes, a new system identification method, referred to as the sequential nonlinear least- square estimation （SNLSE）, is introduced to identify the model parameters. It is shown that the proposed simplified Bouc- Wen model is capable of describing the nonlinear hysteretic behavior of RBs, and that the SNLSE approach is very effective in identifying the model parameters of RBs.

变频电流激励下GIS隔离开关机械缺陷的振动非线性行为及其辨识方法

气体绝缘组合电器(gas insulated switchgear,GIS)机械缺陷是导致设备故障的关键因素之一,为此开展了变频电流激励模式下隔离开关底座松动缺陷的时频域振动图谱变化规律研究,进行了波形因子、重心频率等6个振动特征量的量化分析,采用灰狼算法优化的支持向量机研究提出了变频电流激励模式下GIS隔离开关底座松动缺陷严重程度辨识方法。结果表明:GIS隔离开关缺陷振动信号特征量与电流激励频率具有强相关性,与单一工频电流激励模式相比,变频电流激励具备更有效检测GIS设备机械缺陷的优势;基于126 kV真型GIS试验平台验证获得构建的隔离开关底座松动缺陷辨识模型的平均识别准确率达90%以上。该研究成果为揭示GIS设备的非线性机械振动特性及提升其机械缺陷检测水平提供了重要参考。

高绩效工作系统如何影响员工创新行为--组织认同与服务型领导的作用

积极促进员工创新行为对企业发展具有重要意义,高绩效工作系统是影响员工创新行为的重要前因变量,但现有文献对其影响机理的研究尚显不足。基于社会交换理论与社会认同理论,运用多层线性模型探究了组织认同在高绩效工作系统与员工创新行为之间的中介作用以及服务型领导的调节作用。研究结果表明,高绩效工作系统对员工创新行为具有显著正向影响,组织认同在高绩效工作系统与员工创新行为之间发挥部分中介作用,服务型领导在高绩效工作系统与员工创新行为之间发挥正向调节作用,服务型领导在高绩效工作系统与组织认同之间也发挥正向调节作用,服务型领导正向调节组织认同在高绩效工作系统与员工创新行为之间的中介效应,即服务型领导水平越高,中介效应越显著。

因利感恩?旅游利益感知对乡村旅游地社区居民公民行为的影响机制

乡村旅游地的社区居民公民行为在加强社区治理成果、塑造优质的游客体验及展现良好的乡村精神文明风貌中有着重要作用。文章利用社会交换理论,以肇兴侗寨为案例地,以乡村旅游地居民为研究对象,面向社区和游客分别建立两条影响社区居民公民行为的传导路径,探讨理性因素(旅游利益感知)如何通过非理性因素(社区认同和居民感恩)影响乡村旅游地的社区居民公民行为。结果表明:(1)居民的旅游利益感知能够促进居民的社区认同、对游客的感恩和乡村旅游地的社区居民公民行为;(2)居民的社区认同和对游客的感恩对乡村旅游地的社区居民公民行为具有正向影响;(3)居民的社区认同和对游客的感恩在旅游利益感知和社区居民公民行为之间起部分中介作用。文章对乡村旅游目的地的营销管理和社区治理等方面具有一定的理论意义和实践意义。

教师课堂管理行为多模态解码:行为特征、分类识别与时序发展

教师课堂管理行为的智能评估与精准诊断是数智时代教师素养提升和教育实践变革的关键抓手。研究采用多模态数据融合分析法,深度解码了教师课堂管理行为的模式及其特征。为精确捕获和量化教师课堂管理表现,构建了一个四维分析模型,涵盖了9项一级指标和24项二级指标,通过加权融合多模态数据,实现了对教师课堂管理行为的定量评价。研究结果表明:教师课堂管理行为可归纳为教师中心型、常规稳定型及灵活适应型。教师课堂管理行为特征可总结为自我管理一致性、学生管理弹性、内容聚焦性与环境管理恒常性四个维度。时序分析揭示了教师在教学进程中管理行为的动态演变,从初始的引导学生到赋权学生,连续的策略优化映射出教师专业能力的逐渐展现和对课堂生态的灵活适应。研究深化了对教师课堂管理行为的认识与理解,为未来教师课堂管理行为的评估与优化提供了一种新的分析框架和实证基础。

投桃报李:临时员工助人行为对正式员工隐性知识分享的影响机制

多元雇佣触发的员工内部关系矛盾问题日趋复杂,如何促进多元雇佣聚力发展,已成为零工经济情境下理论和实践领域着力探讨的核心议题。文章基于社会交换理论,引入关系认同和感知义务作为中介变量,将任务相依性作为边界条件,构建临时员工助人行为对正式员工隐性知识分享的双路径机理模型,旨在分析临时员工助人行为对正式员工隐性知识分享的作用效果及潜在机制。通过对三阶段收集的237份纵向数据分析表明:关系认同和感知义务在临时员工助人行为与正式员工隐性知识分享之间起中介作用;任务相依性会强化临时员工助人行为对关系认同和感知义务的影响效应,并且任务相依性能够调节关系认同和感知义务的中介路径,即任务相依性程度越强,临时员工通过关系认同和感知义务对正式员工隐性知识分享的正向影响越强。

企业领导道歉负向影响员工反生产行为机制探究

企业员工由于遭遇领导冒犯所引发的反生产行为因领导道歉改变其负面预期而有所减少。笔者基于资源保存理论,在构建了一个企业领导道歉影响员工反生产行为机制模型的基础上,以分别在两个时间点收集的388份有效追踪数据,运用Mplus软件实证检验了企业领导道歉与员工反生产行为的关系及其变化。检验结果证实:企业领导道歉对员工反生产行为具有显著的负向影响;领导认同和情感承诺分别在领导道歉与员工反生产行为关系间发挥中介作用;领导虚伪感知既负向调节领导道歉对领导认同的影响,也负向调节领导认同在领导道歉与员工反生产行为间的中介作用。本文通过将领导认同、情感承诺和领导虚伪感知等变量尝试性地引入到企业领导道歉影响员工反生产行为模型之中并付诸实证检验,拓展了资源保存理论的应用边际,揭示了企业经营中领导道歉与员工反生产行为二者之间的内在关联,丰富了有关企业管理中领导行为方面的现有文献,研究结论可以为企业领导处理内部人际关系和提高企业治理水平提供理论依据。

适应我国高集中度电力现货市场的发电侧市场力辨识方法

我国电力现货市场发电侧拥有高市场集中度的特点,市场力的滥用辨识变得尤为重要。对美国事前市场力的辨识方法进行了详细综述,分析指出了行为-影响测试方法更适用于我国电力现货市场。在此基础上,进一步研究提出了高市场集中度下的事前-事后市场力辨识方法,包括用于辨识潜在市场力的剩余供给指标测试法和市场模拟仿真法、用于辨识事中市场力的行为-影响测试方法和从市场整体运行情况、用户侧、发电侧和电网侧4个维度进行全面评估的事后市场力辨识方法。最后,通过算例分析,论证了所提市场力辨识方法的合理性和可行性。

失当与适当:价值认同视域下高职学生德育行为的生成逻辑

“立德树人”是高职院校应当秉持的本质使命和历史重任,核心是促进高职学生核心价值观的认同与内化。德育行为借助于高职学生的价值认同来内发生成,其生成机制较为侧重于德育规律的内在生成逻辑,凸显着德育本体论意涵,发挥着德育的价值关切和高职学生发展的意义诉求。高职学生德育行为的生成境遇价值悬置、功能遮蔽、过程偏移和行为失范等失当表现,引发德育工作“失语”风险,造成学生主体出现价值认同危机倾向。高职学生德育行为生成需要从价值复归、功能凸显、过程凝聚和行为内生等方面进行适当调适,最终形成理性僭越、隐而不彰的行为生成图景,建立兼具德育价值认同和行为生成导向的境脉勾勒时空。

数字化背景下供电营业厅服务行为识别研究

为了改善电力服务行业场景复杂,服务行为识别困难的问题,提出了一种供电营业厅服务行为识别融合网络。该网络主要包括时空分割网络模型和改进C3D网络模型。首先,在从视频中提取光流帧和RGB帧。其次,将提取出的光流帧和RGB帧带入时空分割网络和改进C3D网络经过训练,从而有效提取动作特征和图像特征。最后,在分类层,计算每个网络对每类服务动作的识别准确率,通过Softmax公式确定权重,并得到最终动作识别结果。仿真阶段,以南方电网公司提供的服务视频数据集为例,对所提模型进行验证。仿真结果表明,所提方法识别准确率为98.99%,召回率为90.2%,F分数为94.39%。仿真结果进一步验证了所提模型对服务行为具有较高的准确性和稳定的识别率。

道路交通事故认定的多层次救济机制

道路交通事故认定书中的责任认定结论对当事人是否构成交通肇事罪,是否应当接受行政处罚,是否应当进行民事赔偿以及具体数额多少具有重要影响。目前由于相关法律法规将道路交通事故认定书归为“证据”,若对其认定结论不服只能向上一级公安交通管理部门申请复核,法院仅能从证据规则角度审查其是否具有相应证明效力。而在现实中,司法裁判对道路交通事故认定书中的事实陈述和责任判定具有较强依赖性,但因道路交通事故认定书不完全符合证据特征,所能适用的证据规则十分有限,导致法院提供的司法救济具有较大局限性,对当事人的权益保护非常不利。因此应准确把握道路交通事故认定书的实质内容,即道路交通事故认定行为的属性,明确其属于行政确认行为,并以此为理论基础,形成一套公安内部复核—行政复议—行政诉讼的全面多层次的独立救济机制,达到维护公平正义的目标。

关于虚开增值税专用发票罪之“虚开行为”再探讨

增值税发票犯罪案件数量庞多,严重损害了国家的财政收入和税收管理秩序。司法机关在认定虚开增值税专用发票罪的“虚开行为”过程中,存在着诸多争议。认定虚开行为是否需要具有偷税的目的,是否需要造成税收损失,是否还可以适用“三流一致”标准,实务中对此有不同观点。通过对现行法律法规、司法解释归纳总结,对“虚开行为”展开深入分析,提出了统一虚开行为认定标准、完善虚开行为刑法体系、加强司法与税务行政程序衔接等改革建议,以期充分廓清虚开增值税专用发票罪中的“虚开行为”。

基于自然驾驶数据的驾驶换道风格分析与辨识

为了研究在换道工况下个体驾驶行为及其辨识,基于NGSIM轨迹数据提取532组换道有效数据。分析处理驾驶员换道特征参数,运用K-means算法对驾驶员进行聚类分析,可分为谨慎型、一般型、激进型三类。并对聚类的参数进行统计分析和时频分析验证各类驾驶人的差异性,并提取出有效参数作为辨识模型的输入,基于惯性权重非线性变化和粒子最大速度非线性递减的策略来改进粒子群,建立起基于改进粒子群优化SVM的驾驶人风格辨识模型,对SVM模型的两个关键参数C和g进行优化更新,驾驶人识别准确率可达到96.25%,且与BP神经网络、PSO-SVM、随机森林、KNN算法相比具有更高的识别准确率。

组织文化认同对铁路工程企业员工建言行为的影响研究

为激发铁路工程企业员工建言行为的发生,研究以组织文化认同为切入点,在文献理论分析基础上,基于社会认同理论和自我决定理论,引入情感投入和感知组织支持作为组织文化认同和建言行为间关系的中介变量和调节变量,探究组织文化认同对铁路工程企业员工建言行为影响机理。使用组织文化认同和建言行为等成熟量表,以中国铁道建筑总公司、中国铁路工程总公司,中国交通建设集团有限公司企业员工为研究对象进行问卷调查;运用Mplus8.0和SPSS27.0等分析软件对收集数据进行验证性因子分析、相关性分析;在验证性因子分析和相关性分析的基础上,将建立的结构方程模型通过运用Mplus8.0进行路径假设检验;运用fsQCA3.0进行前因变量对建言行为模糊定性比较分析。结构方程模型检验结果表明,组织文化认同显著正向影响情感投入;情感投入正向影响建言行为;即情感投入在组织文化认同和建言行为影响关系中起中介作用;组织文化认同显著正向影响建言行为;感知组织支持显著正向调节情感投入对建言行为的影响。fsQCA分析结果表明,有5种组态可以发生建言行为,其中组织文化认同3个维度为核心存在条件,与结构方程模型检验结果相符合。以上结果丰富了建言行为边界机制和作用条件,基于“想做”和“能做”二元视角,揭示了组织工作氛围中,组织文化认同对员工产生“想建言”的心理动机产生重要影响,感知组织支持(“能建言”)正向促进了员工将建言的动机转化为实际的建言行为,为铁路工程企业管理者在实践中提供建议和启示。

非法捕捞行为“情节严重”认定因素研究

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