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1.
《Journal of The Franklin Institute》2023,360(9):6566-6584
This work concentrates on the control design of interval type-2 (IT2) T–S fuzzy systems under probabilistic saturation constraints. The actual control signals are allowed to exceed some preset thresholds with a certain frequency. Meanwhile, the sensors are governed by the multi-node round-robin scheduling protocol, which permits more than one sensors to transmit their information at every moment. The main objective is to synthesize a fuzzy controller such that the closed-loop system is locally stochastically stable under probabilistic saturated constraints and the multi-node round-robin scheduling protocol. To this end, the probabilistic saturation constraints are characterized by a Bernoulli-distributed stochastic process, and the received state at the controller side is formulated based on an updating rule and a compensation strategy. By constructing new membership functions, a token-dependent control law is subsequently designed. The stability analysis is facilitated by a modified sector condition dealing with the saturation nonlinearities. With suitable selection of initial states, sufficient conditions are derived to achieve the local stochastic stability of the closed-loop IT2 T–S fuzzy system. A larger domain of stochastic stability can be obtained via a searching algorithm. Finally, the proposed method is illustrated via a simulation example. 相似文献
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《Journal of The Franklin Institute》2023,360(10):6783-6803
Fault or anomaly detection is one of the key problems faced by the chemical process industry for achieving safe and reliable operation. In this study, a novel methodology, spectral weighted graph autoencoder (SWGAE) is proposed, wherein, the problem of anomaly detection is addressed with the help of graphs. The proposed approach entails the following key steps. Firstly, constructing a spectral weighted graph, where each time step of a process variable in the multivariate time series dataset is modelled as a node in an appropriately tuned moving window. Subsequently, we propose to monitor the weights of the edges between two nodes that make a connection. The faulty instances are identified based on the discrepancy in the weight pattern compared to normal operating data. To this end, once the weights are determined, they are fed to the auto-encoder network, where reconstruction loss is calculated, and faults are identified if the reconstruction loss exceeds a threshold. Further, to make the proposed approach comprehensive, a fault isolation methodology is also proposed to identify the faulty nodes once the faulty variables are identified. The proposed approach is validated using Tennessee-Eastman benchmark data and pressurized heavy water nuclear reactor real-time plant data. The results indicate that the SWGAE method, when compared to the other state-of-the-art methods, yielded more accurate results in correctly detecting faulty nodes and isolating them. 相似文献
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在采用带精英保留策略的进化算法求解多目标优化问题时,我们需要一个文档来保存在进化过程中产生的不被占优的解。当互不占优的解的数量超过文档的大小时,如何在互不占优的解之间取舍将变得非常重要。针对传统的文档更新策略只考虑解的分布性的情况,提出了一种能够同时保证分布性和收敛性的文档更新策略。该文档更新策略以超体积为基础,与目前经典算法NSGA-Ⅱ进行比较,结果表明新算法拥有良好的分布性,同时也较好地保证了收敛性。 相似文献
4.
《Journal of The Franklin Institute》2022,359(6):2737-2754
The robust fault estimation problem for linear discrete time-varying (LDTV) systems subject to multiplicative noise is investigated by means of finite impulse response (FIR) filter. A novel analytical redundancy, expressed via all states of the previous time window, is originally established to construct the fault estimator. To ensure the satisfactory fault estimation accuracy in stochastic sense under the interference of random uncertainty, a new performance index in forms of matrix trace function is proposed. An easy-to-check necessary and sufficient condition is presented to obtain the optimal filter gain via minimizing the performance index at each time instant. It is analytically demonstrated that, the newly proposed fault estimation algorithm enjoys obvious computational advantages in updating the filter gain, especially as the length of the time window increases for time-varying systems. Simulation results are finally provided to verify its feasibility and superiority. 相似文献
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Peng Yun Panlong Wu Xingxiu Li Shan He Kai Wu 《Journal of The Franklin Institute》2021,358(8):4503-4527
For target tracking systems, the probability of detecting a target is difficult to determine, and the process noise often has non-Gaussian heavy-tailed characteristics owing to interference from outliers. To address the issues associated with single target tracking within clutters in scenarios with an unknown detection probability and heavy-tailed process noise, this paper presents a variational Bayesian-based adaptive probabilistic data association filter (VB-APDAF). The beta distribution, Pearson type VII distribution and multinomial distribution are used to model the detection probability, the process noise, and the association events, respectively. To guarantee the conjugation, a novel parameter estimation strategy is employed. In this strategy, the previous state is introduced in the state update process to construct the joint probability density function of parameters to be estimated and data set. The VB framework is used to estimate the target state, detection probability, and associated events. An experiment was performed under simulated conditions to demonstrate the effectiveness of the proposed filter. 相似文献
7.
Yihong Zhou Yanjiao Wang Fengying Ma Feng Ding Tasawar Hayat 《Journal of The Franklin Institute》2021,358(4):2576-2595
This paper focuses on the parameter estimation for radial basis function-based state-dependent autoregressive models with moving average noises (RBF-ARMA models). An extended projection algorithm is derived based on the negative gradient search. In order to reduce the sensitivity of the algorithm to noise and reduce the fluctuations of the parameter estimation errors, a modified extended stochastic gradient algorithm is proposed. By introducing a moving data window, a modified moving data window-based extended stochastic gradient algorithm is further developed to improve the parameter estimation accuracy. The simulation results show that the proposed algorithms can effectively estimate the parameters of the RBF-ARMA models. 相似文献
8.
《Information processing & management》2016,52(4):682-697
Object matching is an important task for finding the correspondence between objects in different domains, such as documents in different languages and users in different databases. In this paper, we propose probabilistic latent variable models that offer many-to-many matching without correspondence information or similarity measures between different domains. The proposed model assumes that there is an infinite number of latent vectors that are shared by all domains, and that each object is generated from one of the latent vectors and a domain-specific projection. By inferring the latent vector used for generating each object, objects in different domains are clustered according to the vectors that they share. Thus, we can realize matching between groups of objects in different domains in an unsupervised manner. We give learning procedures of the proposed model based on a stochastic EM algorithm. We also derive learning procedures in a semi-supervised setting, where correspondence information for some objects are given. The effectiveness of the proposed models is demonstrated by experiments on synthetic and real data sets. 相似文献
9.
随着信息化进程的推进,在很多重要应用领域发现了大量的不确定性数据,概率是解决不确定信息的比较适用的方法。经典关系数据库处理不了具有概率的数据,所以要对此种数据库在这方面加以推广,也就是概率数据模型。在概率数据库中使用传统的查询方法会使查询结果出现偏差,不能满足用户的需求。因此,基于不确定数据的查询处理受到了越来越多的关注。对此进行了研究。 相似文献
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《Journal of The Franklin Institute》2021,358(15):7900-7915
A novel analytical algorithm called Principal Discriminative Component Analysis (PDCA) is proposed to implement just-in-time feature extraction, so that the deviation between the online monitored data and the normal operating dataset can be timely uncovered. Instead of extracting representative signature inherited in the dataset given from the normal operating condition, the PDCA algorithm can always force the extracted latent features to be extremely discriminative to the inconsistency between the online sampled data and the given dataset. Therefore, the application of the PDCA algorithm in Multi-variate Statistical Process Monitoring (MSPM) can consistently guarantee its salient efficiency in contrast to the counterparts. The superiority and effectiveness of the PDCA-based MSPM approach are demonstrated through comparisons in monitoring both static and dynamic processes. 相似文献
13.
In this paper, a practical technology or solution of quality-related fault diagnosis is provided for nonlinear and dynamic process. Unlike traditional data-based fault diagnosis methods, the alternative approach is focused more on identifying the propagation path that combines diagnostic information and process knowledge. The new method addresses the quality-related fault detection issue with developed nonlinear dynamic latent variable model for extracting nonlinear latent variables that exhibit dynamic correlations, then the advantage of relative reconstruction based contribution approach is followed to analyze the potential root-cause variables. Meanwhile, a new partitioned Bayesian network methodology is proposed for propagation path identification of quality-related faults. Finally, the whole proposed framework is applied to a real hot strip mill process, where the effectiveness is further demonstrated from real industrial data. 相似文献
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本文基于华为公司的创新实践,运用案例研究方法,深入探讨了后发高新技术企业创新能力演化规律和提升机制。研究发现：（1）从资源管理的视角,后发高新技术企业在初级生产阶段、国际化开拓阶段、全球化扩张阶段、创新引领阶段发展历程中创新能力沿着资源建构能力——资源拼凑能力——资源整合能力——资源治理能力的轨迹演化;（2）战略对机会窗口的匹配性决策是后发高新技术企业创新能力能够实现提升的前提和基础,是创新能力提升的先导机制,战略决策对机会窗口的识别、拦截、预测、创造决定着整个组织的发展方向,也决定了创新能力发展;（3）后发高新技术企业创新能力提升的深层机制是,不同阶段的知识结构及学习模式形成一个螺旋递进的上升机制。初级生产阶段实现了积累性学习模式下的组织显性知识积累,国际化开拓阶段达到忘却性学习主导下的组织显性知识的质变,全球化扩张阶段实现积累性学习模式主导下的显隐性知识并重的知识体系,创新引领阶段在积累性学习与忘却性学习的平衡中实现知识的开发与创新。 相似文献
15.
对流换热边界条件下球体内固液相变过程移动热源法求解 总被引：1，自引：0，他引：1
应用移动热源法求解了对流换热条件下球体内具有明显相变界面的固液相变问题,分析了球体半径、相变材料潜热、外界对流换热条件对相变过程的影响,并进一步考虑实际相变过程存在的变对流边界条件,构造了一实用解法.为求解相变问题的数值方法提供了一校核其可靠性的新途径,还为实验结果提供了相互比较的数据.该方法及其结果对相变材料的分析与设计具有重要的实用价值 相似文献
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Bilić-Zulle L 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2011,21(1):49-52
The comparison of methods experiment is important part in process of analytical methods and instruments validation. Passing and Bablok regression analysis is a statistical procedure that allows valuable estimation of analytical methods agreement and possible systematic bias between them. It is robust, non-parametric, non sensitive to distribution of errors and data outliers. Assumptions for proper application of Passing and Bablok regression are continuously distributed data and linear relationship between data measured by two analytical methods. Results are presented with scatter diagram and regression line, and regression equation where intercept represents constant and slope proportional measurement error. Confidence intervals of 95% of intercept and slope explain if their value differ from value zero (intercept) and value one (slope) only by chance, allowing conclusion of method agreement and correction action if necessary. Residual plot revealed outliers and identify possible non-linearity. Furthermore, cumulative sum linearity test is performed to investigate possible significant deviation from linearity between two sets of data. Non linear samples are not suitable for concluding on method agreement. 相似文献
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《Information processing & management》2016,52(3):430-445
The explosion of online user-generated content (UGC) and the development of big data analysis provide a new opportunity and challenge to understand and respond to public opinions in the G2C e-government context. To better understand semantic searching of public comments on an online platform for citizens’ opinions about urban affairs issues, this paper proposed an approach based on the latent Dirichlet allocation (LDA), a probabilistic topic modeling method, and designed a practical system to provide users—municipal administrators of B-city—with satisfying searching results and the longitudinal changing curves of related topics. The system is developed to respond to actual demand from B-city's local government, and the user evaluation experiment results show that a system based on the LDA method could provide information that is more helpful to relevant staff members. Municipal administrators could better understand citizens’ online comments based on the proposed semantic search approach and could improve their decision-making process by considering public opinions. 相似文献
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在科技是第一生产力,人力资源是第一资源的影响下,我国正大力实施以教育为主要阵地的人力资源开发战略,并针对我国教育的落后状况制定了旨在全面提高我国人口整体素质发展战略。对未来一定时期内从业人口中高学历层次指标进行预测。鉴于此,本文特对我国人力资源开发与高等教育发展战略之数量目标进行探究,力求通过国际同时期从业人口中大专及以上学历人数和同GDP总量时从业人口中大专及以上学历人数进行比较,又通过经济发展与产业结构优化升级为模板对从业人口数量的需求的探讨,提出人事数量配置以有效劳动力数量需求为依据;并认为用绝对数来衡量教育发展成效更优于比率,让市场以效率和效益优先进行人员配置,并以此为基础进行人力资源发展战略数量目标预测。 相似文献
19.
Xiaobo Chi Xinchun Jia Fangqin Cheng Maohong Fan 《Journal of The Franklin Institute》2019,356(6):3661-3691
This paper studies networked H∞ filtering for Takagi–Sugeno fuzzy systems with multi-output multi-sensor asynchronous sampling. Different output variables in a dynamic system are sampled by multiple sensors with different sampling rates. To estimate the signals of such a system, a continuous multi-rate sampled-data fusion method is proposed to design a novel networked filter. By considering a class of decentralized event-triggered transmission schemes, multi-channel network-induced delays, and the updating modes of the MOMR sampled-data, a networked jumping fuzzy filter is proposed to estimate system signals based on the transmitted multi-rate sampled-data of fuzzy system and the multi-rate sampled states of filter, and the jumping among filter modes is governed by a Markov process which depends on the arrival times of sampled output sub-vectors. To deal with asynchronous membership functions, the networked fuzzy filtering system is modeled as an uncertain fuzzy stochastic system with membership function deviation bounds. Based on stability and H∞ performance analysis, several membership-function-dependent conditions are presented to co-design the event-triggered transmission schemes and the fuzzy filter such that the filtering error system is robustly mean-square exponentially stable with a prescribed H∞ attenuation level. Finally, the improvement in estimation performance and comparison with the existing filtering methods are discussed through simulation examples. 相似文献
20.
【目的/意义】当前的信息用户行为特征挖掘方法无法将数据统一整合,且无法准确计算出时间序列内滑动
窗口内的数据均值,导致特征挖掘精度偏低。为此,提出了基于时间特性的信息用户行为特征挖掘方法。【方法/过
程】计算时间序列内滑动窗口内的数据均值,得出起始序列向量,再将用户行为划分成若干等值的时间片,通过取
样统计各种用户群体,得出用户的行为状态定性。以平均查询频率作为标准,观察用户的查询行为特征,输出信息
挖掘结果。【结果/结论】实验结果表明：所提方法挖掘出夜晚用户行为信息多于白天,休息日比工作日多,且在网络
波动下,虽然耗时增加,不过处于合理范围内。与传统方法相比,所提方法具有更低的挖掘误差,应用性较强。以
上实验结果证明了基于时间特性的信息用户行为特征挖掘研究能获取更准确的用户行为意向,提高用户兴趣预测
准确度,优化网络服务效果。【创新/局限】为进一步提高网络信息特征挖掘的效率,后续将重点研究多个网络用户
行为的并行分析,使该方法更适用于网络海量信息处理。 相似文献