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Recursive Projected Filter Algorithm with Binary-Valued Observations

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Journal of Systems Science & Complexity 2024年第5期 1832-1860页

作者： ZHANG Xiaoyan WANG Ying XUE Wenchao zhao yanlong Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper focuses on the state estimate for a class of systems with both process noise and measurement noise under binary-valued observations, in which the Gaussian assumption on the predicted density of the state is not required. A recursive projected filter algorithm with time-varying thresholds is constructed to estimate the state under binary-valued observations. The time-varying thresholds are designed as the prediction value of the measurement, which can provide more information about the system state. The convergence property is established with some suitable stability,boundedness and observability conditions. In particular, the estimation error between state and estimate is proved to be asymptotically bounded in the mean-square sense, whose upper bound is related to the variance of process noise. Finally, the theoretical results are demonstrated via numerical examples of first-order and high-order systems.

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MOF基材料吸附去除食品污染物研究进展

北京工业大学学报 2024年第6期50卷 763-776页

作者：赵砚珑黄光灿陈强北京工业大学环境与生命学部北京100124

食品安全不仅直接关系到人民群众的生命健康,而且还是社会和谐稳定的重要基础。食品在生产、加工、储存等过程中均可能产生或引入各种类型的污染物,例如重金属、有机农药、染料、真菌毒素和持久性有机污染物等。去除被污染食品中的污染... 详细信息

食品安全不仅直接关系到人民群众的生命健康,而且还是社会和谐稳定的重要基础。食品在生产、加工、储存等过程中均可能产生或引入各种类型的污染物,例如重金属、有机农药、染料、真菌毒素和持久性有机污染物等。去除被污染食品中的污染物是保证食品安全和人类健康的重要举措,目前主要的处理手段包括催化降解、化学氧化、萃取、酶降解、微生物降解及吸附去除等方法。其中吸附法较其他方法来说具有工艺简便、能耗低、操作灵活等优势,是处理食品污染物最具前景的方式之一。金属有机框架(metal-organic frameworks,MOFs)是一类新兴的多孔材料,比表面积大、孔隙率高、孔道可修饰等特点使其在吸附去除食品污染物方面具有广阔的研究与应用前景。介绍了近年来MOF基吸附剂吸附去除各类食品污染物的主要研究进展;从静电作用、酸碱/配位作用、π-π堆积作用、氢键作用以及协同作用等方面系统总结了MOF基吸附剂对食品污染物的各类吸附机理;对该类研究所面临的挑战及未来发展趋势进行了总结与展望,旨在为食品安全领域MOF基吸附剂的研究提供实例借鉴与理论指导。

关键词：金属有机框架(MOFs) 吸附吸附剂吸附机理食品安全食品污染物

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基于转移概率分布的组合信用转移风险参数估计与压力测试

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系统工程理论与实践 2024年第3期44卷 893-911页

作者：史若诗何寅杰赵延龙包莹中国工商银行博士后科研工作站北京100140 中国科学院数学与系统科学研究院系统控制重点实验室北京100190 中国科学院大学数学科学学院北京100049 中国工商银行总行风险管理部北京100140

近年来,压力测试因其衡量金融危机等极端环境下风险的特性在现代银行风险管理中发挥着越来越重要的作用.准确衡量组合风险受系统性因素的驱动作用,是有效控制金融风险,防范金融危机的关键.本文研究了组合信用风险参数估计与压力测试问题... 详细信息

近年来,压力测试因其衡量金融危机等极端环境下风险的特性在现代银行风险管理中发挥着越来越重要的作用.准确衡量组合风险受系统性因素的驱动作用,是有效控制金融风险,防范金融危机的关键.本文研究了组合信用风险参数估计与压力测试问题,建立了包含系统性因子和多级相关性系数的Vasicek信用转移模型,分析了相关性系数对各评级间信用转移概率的影响,给出了使得评级单调一致的相关性系数条件,保证了信用评级转移概率的单调一致性;构造了基于降级概率分布的参数估计方法,利用转移概率矩阵推导出市场均衡状态下的评级寿命分布,进而给出了相关性系数和系统性因子的估计算法.与已有算法相比,本文提出的方法减弱了系统性因子固定偏差的影响,克服了算法对系统性因子分布的依赖,在降低计算代价的同时提高了估计的精确度.仿真实验结果表明,本文提出的方法有效提高了计算速度,对系统性因子、相关系数及组合损失的估计效果都显著优于已有方法;利用该方法估计的极端损失可以更充分地覆盖样本外组合损失,使得在压力测试中能够更好地预判和防范金融风险,维护金融市场稳定.

关键词：组合信用风险 Vasicek模型信用转移概率矩阵压力测试

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Consensus of switched multi-agent systems with binary-valued communications

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Science China(Information Sciences) 2022年第6期65卷 189-202页

作者： Min HU Ting WANG yanlong zhao The Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper studies the consensus of switched multi-agent systems(MAS) with binary-valued communications. Different from the existing studies on switched MAS considering precise observations,each agent studied in this research only receives binary-valued information with stochastic noises from its neighbors’ states. Further, unlike the existing studies on MAS with binary-valued information in a fixed topology, in this paper, we consider the jointly connected undirected graphs, each of which switches with non-zero probability. The consensus algorithm comprises of two stages: first, the connected agents employ a recursive projection algorithm to estimate their neighbors’ states based on the binary-valued communications;second, the control law of the connected agents is developed based on the estimations to upgrade their *** is proved that both the speed of the estimation convergence to the real states and the consensus speed of the states can achieve O(1/t) when the iteration step is given a proper value. Furthermore, the results indicate that the larger the value of the lowest probability that a graph emerges with, the more easily the consensus could be achieved. Finally, a simulation is presented to demonstrate the theoretical analysis.

关键词： binary-valued system switched multi-agent system recursive projection algorithm consensus jointly connected undirected topologies

System identification under saturated precise or set-valued measurements

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Science China(Information Sciences) 2023年第1期66卷 224-243页

作者： yanlong zhao Hang ZHANG Ting WANG Guolian KANG Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences Institute of Artificial Intelligence University of Science and Technology Beijing Department of Biostatistics St.Jude Children's Research Hospital

This paper considers the system identification problem based on saturated precise or set-valued measurements, which is widely used in various fields and has essential difficulties. Since existing methodologies cannot make full use of the mixed data, this paper is aiming to fill the gap and build a unified framework in dealing with such problems rigorously and comprehensively. New algorithms are introduced and their properties are established. Most significantly, the Cramécr-Rao(CR) lower bound based on the measurements is established, which consists of two parts with respect to the precise data and set-valued data, respectively. This prompts the idea of designing an estimation algorithm by grouping and combining the estimations under two classifications of data. As a result, a CR lower bound-based algorithm(CRBA) is constructed. The convergence properties are theoretically analyzed in terms of consistency and asymptotic efficiency under periodic inputs. For general inputs, an algorithm based on the CRBA that combines the expectation maximization(EM) algorithm for set-valued subsystems and the gradient descent algorithm for precise subsystems is proposed. Numerical simulations validate the superiority of the proposed algorithms.

关键词： system identification Cramér-Rao lower bound truncated data precise measurement set-valued measurement

新时期高等教育教学评价及其高质量发展路径探析

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黑龙江工业学院学报（综合版） 2024年第5期24卷 7-10页

作者：徐亿军赵彦龙哈尔滨学院经济管理学院黑龙江哈尔滨150086

中国式高等教育现代化内涵发展的核心即是提高教育教学质量。而高校教育教学质量评价既是有效实施教学质量管理的重要内容,同时更是高等教育实现高质量内涵发展的重要途径。基于此,论文探讨了新时期中国高等教育高质量发展提出的背景及... 详细信息

中国式高等教育现代化内涵发展的核心即是提高教育教学质量。而高校教育教学质量评价既是有效实施教学质量管理的重要内容,同时更是高等教育实现高质量内涵发展的重要途径。基于此,论文探讨了新时期中国高等教育高质量发展提出的背景及其重要意义,以及高校教育教学评价对高等教育高质量发展的积极推动作用,并着重探究了全面提升高等教育教学评价及其高质量发展的路径,以期为中国式高等教育现代化及高质量发展提供有益的借鉴。

关键词：高等教育高质量发展教学质量教育教学评价

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高密度超长碳纳米管的可控制备:进展与展望

化工学报 2024年第4期75卷 1355-1369页

作者：刘恺轩姜沁源汪菲李润朱平王康康臧永路赵彦龙张如范清华大学化学工程系清洁能源化工技术教育部工程研究中心北京100084

碳纳米管因其优异的力学、电学、热学和光学性能,在碳基集成电路、超强超韧纤维、机械储能、柔性可穿戴设备等众多尖端领域拥有广阔的应用前景。碳纳米管的单体结构和微观形貌(如长度、取向度、缺陷浓度、洁净程度等)对其基础物理性质... 详细信息

碳纳米管因其优异的力学、电学、热学和光学性能,在碳基集成电路、超强超韧纤维、机械储能、柔性可穿戴设备等众多尖端领域拥有广阔的应用前景。碳纳米管的单体结构和微观形貌(如长度、取向度、缺陷浓度、洁净程度等)对其基础物理性质有显著的影响。在各类碳纳米管中,只有具有宏观长度、低缺陷浓度和高取向度的超长碳纳米管才能充分体现和发挥其本征的性能优势并满足很多尖端领域对其结构和性能的严格要求。实现超长碳纳米管实际应用的关键在于实现其大规模制备,然而其目前的产率远远无法满足应用需求,因而其在高密度、高产率制备方面依然面临很多挑战。深入讨论了超长碳纳米管的生长机理,分析了超长碳纳米管产率低的原因,系统总结了高密度超长碳纳米管的制备方法,并介绍了目前在超长碳纳米管实际应用方面的最新进展。另外,还总结了超长碳纳米管制备领域所面临的科学和技术挑战,并对未来的发展方向进行了深入的讨论。

关键词：超长碳纳米管高产率可控制备

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System identification with binary-valued observations under both denial-of-service attacks and data tampering attacks:the optimality of attack strategy

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Control Theory and Technology 2022年第1期20卷 127-138页

作者： Jin Guo Xuebin Wang Yanling Zhang Wenchao Xue yanlong zhao School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Knowledge Automation for Industrial Processes Ministry of EducationBeijing100083China Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China

With the development of wireless communication technology,cyber physical systems are applied in various fields such as industrial production and infrastructure,where lots of information exchange brings cyber security threats to the *** the perspective of system identification with binary-valued observations,we study the optimal attack problem when the system is subject to both denial of service attacks and data tampering *** packet loss rate and the data tampering rate caused by the attack is given,and the estimation error is *** the optimal attack strategy to maximize the identification error with the least energy is described as a min–max optimization problem with *** explicit expression of the optimal attack strategy is *** examples are presented to verify the effectiveness of the main conclusions.

关键词： System identification Binary-valued observations Denial-of-service attacks Data tampering attacks

米诺环素联合丁香油对可复性牙髓炎患者牙髓活力、疼痛程度及炎性因子的影响

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药品评价 2024年第4期21卷 486-489页

作者：赵延龙董新新周清许昌市中心医院河南许昌461000

目的研究可复性牙髓炎患者使用米诺环素联合丁香油对牙髓活力、疼痛程度及炎性因子的影响。方法选入许昌市中心医院的126例可复性牙髓炎患者,将使用米诺环素联合丁香油治疗的63例患者作为联合组,将仅使用丁香油治疗的63例患者作为单一组... 详细信息

目的研究可复性牙髓炎患者使用米诺环素联合丁香油对牙髓活力、疼痛程度及炎性因子的影响。方法选入许昌市中心医院的126例可复性牙髓炎患者,将使用米诺环素联合丁香油治疗的63例患者作为联合组,将仅使用丁香油治疗的63例患者作为单一组,对比两组牙髓活力、疼痛程度、炎性因子、疗效。结果治疗后,联合组牙髓活力冷诊法测试结果整体优于单一组,差异有统计学意义(P<0.05);联合组牙髓活力热诊法测试结果优于单一组,差异有统计学意义(P<0.05);联合组整体疼痛程度优于单一组,差异有统计学意义(P<0.05);联合组炎性因子四项均比单一组低,差异有统计学意义(P<0.05)。联合组总有效率比单一组高,差异有统计学意义(P<0.05)。结论可复性牙髓炎患者运用米诺环素联合丁香油能够提升牙髓活力冷热诊法测试结果,能够提升牙髓活力,减轻疼痛程度,降低炎性因子的影响。

关键词：米诺环素丁香油可复性牙髓炎影响