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Dual-Stage Hybrid Learning Particle Swarm Optimization Algorithm for Global Optimization Problems

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Complex System Modeling and Simulation 2022年第4期2卷 288-306页

作者： Wei Li Yangtao Chen Qian Cai cancan wang Ying Huang Soroosh Mahmoodi the School of Information Engineering Jiangxi University of Science and TechnologyGanzhou 341000China the School of Mathematical and Computer Science Gannan Normal UniversityGanzhou 341000China the Soroosh Khorshid Iranian Co. Abyek Industrial ZoneQazvin 999067Iran

Particle swarm optimization(PSO)is a type of swarm intelligence algorithm that is frequently used to resolve specific global optimization problems due to its rapid convergence and ease of ***,PSO still has certain deficiencies,such as a poor trade-off between exploration and exploitation and premature ***,this paper proposes a dual-stage hybrid learning particle swarm optimization(DHLPSO).In the algorithm,the iterative process is partitioned into two *** learning strategy used at each stage emphasizes exploration and exploitation,*** the first stage,to increase population variety,a Manhattan distance based learning strategy is *** this strategy,each particle chooses the furthest Manhattan distance particle and a better particle for *** the second stage,an excellent example learning strategy is adopted to perform local optimization operations on the population,in which each particle learns from the global optimal particle and a better *** the Gaussian mutation strategy,the algorithm’s searchability in particular multimodal functions is significantly *** benchmark functions from CEC 2013,DHLPSO is evaluated alongside other PSO variants already in *** comparison results clearly demonstrate that,compared to other cutting-edge PSO variations,DHLPSO implements highly competitive performance in handling global optimization problems.

关键词： particle swarm optimization Manhattan distance example learning gaussian mutation dual-stage global optimization problem

A passive wireless surface acoustic wave(SAW)sensor system for detecting warfare agents based on fluoroalcohol polysiloxane film

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Microsystems & Nanoengineering 2024年第1期10卷 67-78页

作者： Yong Pan cancan Yan Xu Gao Junchao Yang Tengxiao Guo Lin Zhang Wen wang State Key Laboratory of NBC Protection for Civil Beijing 102205China Institute of Acoustics Chinese Academy of SciencesBeijing 100190China The School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China

Long-term monitoring of environmental warfare agengts is a challenge for chemical gas *** address this issue,we developed a 433 MHz passive wireless surface acoustic wave(WSAW)gas sensor for dimethyl methylphosphonate(DMMP)*** WSAW gas sensor includes a YZ lithium niobate(LiNbO_(3))substrate with metallic interdigital transducers(IDTs)etched on it,and an antenna was placed near the IDT.A DMMP-sensitive viscoelastic polymer fluoroalcoholpolysiloxane(SXFA)film was prepared on a LiNbO_(3) substrate,and mode modeling coupling was used to optimize the design *** sensor can function properly in an environments between−30℃ and 100℃ with humidity less than 60%*** the wireless transmission distance was within the range of 0-90 cm,the sensor noise increased with distance,and the stability was less than 32°/*** optimizing the film thickness of SXFA,a relationship was observed between sensor sensitivity and film *** the film thickness of SXFA reached 450 nm,the optimal value was *** a distance of 20 cm between the transmitting and receiving antennas,DMMP was detected at different concentrations with the developed WSAW gas *** lower detection limit of DMMP was 0.48 mg/m^(3),the sensitivity of the sensor was 4.63°/(mg/m^(3)),and repeatable performance of the sensor was confirmed.

关键词： film alcohol passive

Neural Networks Combined with Importance Sampling Techniques for Reliability Evaluation of Explosive Initiating Device

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Chinese Journal of Aeronautics 2012年第2期25卷 208-215页

作者： GONG Qi ZHANG Jianguo TAN Chunlin wang cancan Reliability System Engineering Institute Beihang Universitys Beij ing 100191 China Beijing lnstitute of Spacecraft System Engineering Beijing 100081 China

Concerning the issue of high-dimensions and low-failure probabilities including implicit and highly nonlinear limit state function, reliability analysis based on the directional importance sampling in combination with the radial basis function （RBF） neural network is used, and the RBF neural network based on first-order reliability method （FORM） is to approximate the unknown implicit limit state functions and calculate the most probable point （MPP） with iterative algorithm. For good efficiency, based on the ideas that directional sampling reduces dimensionality and importance sampling focuses on the domain contributing to failure probability, the joint probability density function of importance sampling is constructed, and the sampling center is moved to MPP to ensure that more random sample points draw belong to the failure domain and the simulation efficiency is improved. Then the numerical example of initiating explosive devices for rocket booster explosive bolts demonstrates the applicability, versatility and accuracy of the approach compared with other reliability simulation algorithm.

关键词： neural networks importance sampling explosive initiating device reliability nonlinearity

低能量体外冲击波绘制疼痛地图治疗男性膀胱过度活动症伴盆腔痛的临床疗效分析

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临床泌尿外科杂志 2024年第2期39卷 93-97页

作者：张家奇罗成张新萍王灿灿李厚泽姚淼关永晖新疆医科大学第一附属医院泌尿中心乌鲁木齐830054

目的:探讨低能量体外冲击波绘制盆底肌疼痛地图治疗男性膀胱过度活动症伴盆腔痛的临床疗效。方法:收集2022年6月—2023年5月新疆医科大学第一附属医院泌尿综合治疗区收治的膀胱过度活动症伴随盆腔疼痛的男性患者共92例。根据治疗方式分... 详细信息

目的:探讨低能量体外冲击波绘制盆底肌疼痛地图治疗男性膀胱过度活动症伴盆腔痛的临床疗效。方法:收集2022年6月—2023年5月新疆医科大学第一附属医院泌尿综合治疗区收治的膀胱过度活动症伴随盆腔疼痛的男性患者共92例。根据治疗方式分为研究组和对照组,研究组(49例)采用低能量体外冲击波绘制疼痛地图,对激痛点进行冲击波干预;对照组(43例)采用低能量体外冲击波对患者会阴部位和膀胱部位进行治疗。评估2组患者治疗前及治疗后的随访数据,比较问卷评分:包括膀胱过度活动症症状评分(overactivebladder symptomscore,OABSS)、疼痛评分(numeric rating scale,NRS)、生活质量影响评分和汉密尔顿焦虑量表(Hamilton anxiety rating scale,HAMA)等的变化。结果:与治疗前比较,对照组的OABSS评分、NRS评分、生活质量影响评分、HAMA评分均有显著改善(P0.05)。结论:低能量体外冲击波疗法能够明显改善膀胱过度活动症伴随盆腔疼痛患者的下尿路症状和疼痛症状,且针对疼痛地图中激痛点定位击打的冲击波治疗效果优于直接使用冲击波击打会阴部和膀胱区。

关键词：膀胱过度活动症盆腔痛低能量体外冲击波疼痛地图

Catalytic Thiourea Promoted Electrophilic Thiocyanation of Indoles and Aromatic Amines with NCS/NH4SCN

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Chinese Journal of Chemistry 2016年第11期34卷 1081-1085页

作者： cancan wang Zhonghao wang Liang wang Qun Chen Mingyang He School of Petrochemical Engineering Changzhou University Changzhou Jiangsu 213164 China

A simple and efficient protocol for the electrophilic thiocyanation of indoles and aromatic amines with thiourea/NCS/NH4SCN system has been developed. The major features of the present procedure are the mild conditions, good yields, short reaction times, and the use of inexpensive and readily available organocatalyst. Moreover, N-chlorosueeinimide （NCS） was found to be indispensable, and thiourea could greatly promote the reaction.

关键词： thiocyanation indoles aromatic amines catalytic thiourea N-chlorosuccinimide

3D digital-image correlation insight into generalized relaxation behavior of sandstone under stress and pore pressure coupling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2516-2536页

作者： cancan Chen Heping Xie Jiang Xu Seisuke Okubo Shoujian Peng Cunbao Li Minghui Li State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering Shenzhen UniversityShenzhen518060China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and GreenEnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen518060China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400044China

The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of ***,the idealization boundary condition for constant stress in creep or constant strain in relaxation is not usually attained in natural geological ***,generalized relaxation tests that explore the simultaneous changes of stress and strain with time under different stress levels with constant pore-water pressure are conducted in this *** results show that in area I,area II,and area III,the stress and strain both change synchronously with time and show similar evolutionary laws as the strain-time curve for creep or the stress-time curve for *** the applied stress level surpasses the sci or scd threshold,the variations in stress and strain and their respective rates of change exhibit a significant *** radial deformation and its rate of change exhibit greater sensitivity in response to stress *** apparent strain deforms homogeneously at the primary stage,and subsequently,gradually localizes due to the microcrack development at the secondary ***,interconnection of the microcracks causes the formation of a shear-localization zone at the tertiary *** strain-time responses inside and outside the localization zone are characterized by local strain accumulation and inelastic unloading during the secondary and tertiary stages,*** width of the shear-localization zone is found to range from 4.43 mm to 7.08 mm and increased with a longer *** electron microscopy(SEM)reveals a dominant coalescence of intergranular cracks on the fracture surface,and the degree of physiochemical deterioration caused by water-rock interaction is more severe under a longer *** brittle sandstone’s time-dependent deformation is essentially controlled by microcrack development during generalized relaxation,and its expectancy-life is determi

关键词： Generalized relaxation Stress level Direction coefficient Major-strain field Microcrack damage Stress threshold

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资本市场透明度研究新进展

经济学动态 2022年第6期 131-149页

作者：胡海峰王灿灿北京师范大学经济与工商管理学院 100875

资本市场透明度对于资本市场效率和实体经济发展具有重要意义,是各国政府和学界高度重视的话题。本文从资本市场透明度的概念界定、测度、影响因素、经济后果四个方面对代表性文献进行评述。首先,学界对透明度概念的探讨主要围绕信息内... 详细信息

资本市场透明度对于资本市场效率和实体经济发展具有重要意义,是各国政府和学界高度重视的话题。本文从资本市场透明度的概念界定、测度、影响因素、经济后果四个方面对代表性文献进行评述。首先,学界对透明度概念的探讨主要围绕信息内容、质量、信息使用者等三个方面展开,测度方法主要从信息披露内容、代理指标及综合指标等角度来构建,但未形成统一认识。其次,信息披露相关的内部治理、外部治理、非正式机制、宏观因素四个方面是影响透明度的重要因素。再次,透明度对公司、资本市场、实际经济活动都会产生显著影响。最后,本文认为未来研究重点包括透明度概念和测度体系、激励机制理论及其对透明度的影响、透明度影响因素之间的交叉效应、透明度对社会和实体经济影响的实证研究。

关键词：资本市场透明度信息披露

Symmetry dependent activation and reactivity of peroxysulfates on FeS_(2)(001)surface

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Science Bulletin 2024年第2期69卷 154-158页

作者： cancan Ling Meiqi Li Hao Li Xiufan Liu Guangming Zhan Hongwei Sun Chuan Liang Yaling Li Bing Zhou Jincai Zhao Lizhi Zhang School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Pesticide&Chemical Biology of Ministry of Education Institute of Environmental&Applied ChemistryCentral China Normal UniversityWuhan 430079China

Heterogeneous peroxysulfates-based advanced oxidation processes(AOPs)have garnered significant attention for purifying organic wastewater since they offer many advantages like low cost,safe storage,facile activation and reactive species participation[1].Nonradical and radical pathways have been proposed to be involved in peroxysulfates activation.

关键词： activation radical reactivity

资本市场开放有助于减少内幕交易吗?——基于沪港通准自然实验的证据

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中国经济问题 2023年第4期 149-164页

作者：胡海峰王灿灿北京师范大学经济与工商管理学院

资本市场开放一方面,加快了中国经济融入世界经济的步伐,是推动中国经济发展的重要因素;另一方面,资本的自由流动也可能引发高频投机交易等金融风险问题。本文以“内地与香港地区股票市场交易互联互通机制”启动为背景,利用2010—2015年... 详细信息

资本市场开放一方面,加快了中国经济融入世界经济的步伐,是推动中国经济发展的重要因素;另一方面,资本的自由流动也可能引发高频投机交易等金融风险问题。本文以“内地与香港地区股票市场交易互联互通机制”启动为背景,利用2010—2015年A股上市公司数据,发现资本市场开放短期会引发内幕交易可能性显著上升。对于具有较高透明度、较好治理水平和较严监管环境的公司而言,资本市场开放助长的内幕交易会受到一定遏制。本文研究为推动资本市场开放进程和治理水平协同发展理念提供了经验证据。

关键词：内幕交易资本市场开放自由化沪港通