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1.
The formation of public opinion on the network is a hot issue in the field of complex network research, and some classical dynamic models are used to solve this problem. The signed network is a particular form of the complex network, which can adequately describe the amicable and hostile relationships in complex real-world systems. However, the methods for studying the dynamic process of public opinion propagation on signed networks still require to be further discussed. In this paper, the authors pay attention to the influence of negative edges in order to design a two-state public opinion propagation mechanism suitable for signed networks. The authors first set the interaction rules between nodes and the transition rules of node states and then apply the model to synthetic and real-world signed networks. The simulation results show that there is a critical value of the negative edge ratio.When the negative edge ratio exceeds this critical value, the evolutionary result of public opinion will change from a consistent state to a split state. This conclusion is also consistent with the distribution result of opinions within communities in the signed network. Besides, the research on the network structural balance shows that the model makes the network evolve in a more balanced direction. 相似文献
2.
随着信息技术发展,设备健康数据与知识图谱技术结合为设备健康发展带来新的发展机遇,知识图谱利用其多种特异性优势,使企业系统中积累的海量设备维修数据得到有效整合利用.本文提出基于知识图谱的核电设备健康管理知识建模与分析方法,并根据实体关系模型构建维修知识图谱本体框架,同时基于核电企业实际的维修工单数据,从统计分析和关联分析两方面取得良好的实践效果.研究结果表明,知识图谱能够在设备维修知识的集成上解决传统的数据孤岛问题,同时能基于故障的可视化分析为维修人员和管理人员提供决策和知识支持. 相似文献
3.
在恒定的法向载荷下,使用Rockwell C 120°金刚石压头对聚碳酸酯(PC)、熔融石英、紫铜和镁合金AZ31进行微米划痕测试,研究滑动速度对试样划痕响应的影响.压入深度小于压头的球锥转变深度,确保仅有压头顶端的圆球部分与试样接触.结果表明:随着滑动速度的增加,压入深度、残余深度和划痕沟槽的宽度均非线性减小,划痕硬度和弹性恢复率均非线性增大;PC和紫铜的划痕摩擦系数先增大后减小,PC的黏弹性行为对其摩擦响应有显著影响;熔融石英的划痕摩擦系数先增大后减小,最后趋于稳定;镁合金AZ31的划痕摩擦系数先减小后增大.熔融石英、紫铜和镁合金AZ31的划痕摩擦系数的变化趋势可通过几何接触模型进行解释. 相似文献
4.
In this era of big data, data are often collected from multiple sources that have different reliabilities, and there is inevitable conflict with respect to the various information obtained when it relates to the the same object.One important task is to identify the most trustworthy value out of all the conflicting claims, and this is known as truth discovery. Existing truth discovery methods simultaneously identify the most trustworthy information and source reliability degrees and are based on the idea that more reliable sources often provide more trustworthy information,and vice versa. However, there are often semantic constrains defined upon relational database, which can be violated by a single data source. To remove violations, an important task is to repair data to satisfy the constrains,and this is known as data cleaning. The two problems above may coexist, but considering them together can provide some benefits, and to the authors knowledge, this has not yet been the focus of any research. In this paper, therefore, a schema-decomposing based method is proposed to simultaneously discover the truth and to clean the data, with the aim of improving accuracy. Experimental results using real world data sets of notebooks and mobile phones, as well as simulated data sets, demonstrate the effectiveness and efficiency of our proposed method. 相似文献
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6.
基于偏振复用原理和反射式半导体光放大器RSOA(reflective semiconductor optical amplifier)的再调制特性,融入了光载无线RoF(radio over fiber)技术,设计了一种新型的可以实现多种信号混传的波分复用无源光网络WDM-PON(wavelength division multiplexing passive optical network)系统。在中心站,无线信号和有线信号同时调制到两个偏振态正交的光载波上,并耦合到标准单模光纤中传输。在基站,将两个偏振态正交的信号分离后,一方面可以探测得到四倍频毫米波信号和有线信号,另一方面还可以通过RSOA实现载波重用。通过Optisystem软件对该系统进行模拟仿真,得到了调制信号的光谱和接收端信号的眼图,分析了传输信号误码率与接收光功率的关系,结果表明,该系统传输性能良好。 相似文献
7.
In this paper, the optimal maintenance policy is investigated for a system with stochastic lead time and two types of failures. The system has two types of failures, one type is repairable, when the repairable failure occurs, the system will be repaired by repairman, and the system after repair is not "as good as new". The other type of failure is unrepairable, and when the unrepairable failure occurs the system must be replaced by a new and identical one. The spare system for replacement is available only by order, and the lead time for delivering the spare system is stochastic. The successive survival times of the system form a stochastically decreasing geometric process, the consecutive repair times after failures of the system form a renewal process. By using the renewal process theory and geometric process theory, the explicit expression of the long-run average cost per unit time under ordering policy(N-1) is derived, and the corresponding optimal can be found analytically. Finally,the numerical analyses are given. 相似文献
8.
It is shown that the collapse dynamics in the CSL model will entangle two independent systems under certain conditions, and their state after collapse may be an entangled superposition of spatially separated states. However, since the conditions can hardly be satisfied in reality, the occurrence of such superpositions is very improbable, and thus collapse theories still provide a promising solution to the measurement problem. 相似文献
9.
In this paper, influences on the reservoir permeability, the reservoir architecture and the fluid flow pattern caused by hydraulic fracturing are analyzed. Based on the structure and production fluid f... 相似文献
10.
为定量解决非支配解排序问题,并兼顾多目标粒子群优化算法(multi-objective particle swarm optimization,MOPSO)的收敛性和多样性,提出了一种基于 Pareto 云隶属度的 MOPSO 算法。利用 Logistic 混沌映射优化种群的初始空间分布并融合布谷鸟搜索(cuckoo search,CS)指导粒子跳出局部陷阱,以增强算法的全局寻优能力。首次提出云向量评价 Pareto 最优解集方法,采用云隶属度评价准则对粒子适应度值进行量化评价。依据云隶属度选取个体最优和群体最优,平衡全局开发与开采,进而实现外部档案维护。测试函数集 ZDT 的实验结果表明,改进算法在收敛性和多样性方面较 MOPSO 和 NSGA-Ⅱ有一定优势。 相似文献