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基于多核SVR集成模型与主动学习的结构可靠性分析方法

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工程力学 2024年

作者：杜尊峰樊涛赵亚琦温家朋天津大学复杂管理系统实验室天津大学水利工程智能建设与运维全国重点实验室

目前基于代理模型与蒙特卡洛模拟（Monte Carlo Simulation，mcs）相结合的可靠性分析方法大多依赖于Kriging模型，而基于其他代理模型的可靠性分析方法仍然较少。本文将多种不同核函数下的支持向量机回归（Support Vector Regression，... 详细信息

目前基于代理模型与蒙特卡洛模拟（Monte Carlo Simulation，mcs）相结合的可靠性分析方法大多依赖于Kriging模型，而基于其他代理模型的可靠性分析方法仍然较少。本文将多种不同核函数下的支持向量机回归（Support Vector Regression，SVR）模型进行集成，结合主动学习与mcs提出了一种新的结构可靠性分析方法；该方法利用四分位距（Inter Quartile Range，IQR）对多核SVR集成模型的预测值的局部不确定性进行估计，并基于IQR给出的预测不确定性值，构建主动学习函数开展SVR集成模型的自适应更新直至满足收敛条件；通过3个算例验证了所提方法的有效性与准确性，计算结果表明，该方法对多失效域、非线性、高维度问题具有较好的适用性和高效性，虽然集成模型相较于单一模型在建模成本上有所增加，但在面对高维问题时，所提方法整体计算效率与计算精度均优于基于Kriging模型的可靠性分析方法。

关键词：结构可靠性主动学习函数核函数 SVR模型 mcs

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现阶段中尺度对流系统的识别方法浅析

农业灾害研究 2024年第1期14卷 133-135页

作者：刘婉清内蒙古自治区乌海市气象局内蒙古乌海016000

通过比较分析中尺度对流系统中的雷达资料和卫星资料,对国内外现有的mcs研究方法进行阐述,得出结论:从资料完整性、目标云团的尺度覆盖、资料的获取方法、软件识别手段等来看,基于卫星资料的识别mcs相较传统的雷达资料具有分析更为准确... 详细信息

通过比较分析中尺度对流系统中的雷达资料和卫星资料,对国内外现有的mcs研究方法进行阐述,得出结论:从资料完整性、目标云团的尺度覆盖、资料的获取方法、软件识别手段等来看,基于卫星资料的识别mcs相较传统的雷达资料具有分析更为准确、便捷和高效的特点,值得推广。

关键词： mcs 雷达静止卫星强对流自动追踪红外云图

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Joint Energy Predication and Gathering Data in Wireless Rechargeable Sensor Network

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Computer Systems Science & Engineering 2023年第3期44卷 2349-2360页

作者： I.Vallirathi S.Ebenezer Juliet Department of Computer Science and Engineering PET Engineering CollegeVallioor627117India Department of Computer Science and Engineering VV College of EngineeringThisayanvilai627657India

Wireless Sensor Network(WSNs)is an infrastructure-less wireless net-work deployed in an increasing number of wireless sensors in an ad-hoc manner.As the sensor nodes could be powered using batteries,the development of WSN energy constraints is considered to be a key issue.In wireless sensor networks(WSNs),wireless mobile chargers(mcs)conquer such issues mainly,energy shortages.The proposed work is to produce an energy-efficient recharge method for Wireless Rechargeable Sensor Network(WRSN),which results in a longer lifespan of the network by reducing charging delay and maintaining the residual energy of the sensor.In this algorithm,each node gets sorted using the K-means technique,in which the data gets distributed into various clusters.The mobile charges execute a Short Hamiltonian cycle opposite direction to reach each cluster’s anchor point.The position of the anchor points is calculated based on the energy distribution using the base station.In this case,the network will act as a spare MC,so that one of the two mcs will run out of energy before reaching the BS.After the current tours of the two mcs terminate,regression analysis for energy prediction initiates,enabling the updating of anchor points in the upcoming round.Based on thefindings of the regression-based energy prediction model,the recommended algorithm could effectively refill network energy.

关键词： WSNs mcs WRSN K-means algorithm shortest hamiltonian cycle regression analysis

Spatiotemporal dynamics of cell abundance,colony size and intracellular toxin concentrations of pelagic and benthic Microcystis in Lake Caohai,China

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Journal of Environmental Sciences 2019年第10期31卷 184-196页

作者： Bing Feng Chunbo Wang Xingqiang Wu Cuicui Tian Meng Zhang Yingying Tian Bangding Xiao Key Laboratory of Algal Biology of Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072China Jiangxi Academy of Environmental Sciences Nanchang 330039 China Henan institute of technology Henan 453003 China

Lake Caohai has experienced extensive Microcystis blooms in recent years,and to improve its water quality,the local government carried out a series of water control measures.To better understand the dynamics of both pelagic and benthic Microcystis and their characteristics in Lake Caohai,we conducted a 1-year investigation from December 2015to December 2016 to gain a seasonal outlook on the distribution and dynamics of cell abundance,colony size and intracellular microcystins(mcs)of Microcystis.The results indicated that the Microcystis bloom occupied primarily the northeastern region and then moved gradually from lakeshore to lake center.The perennial southwesterly winds and the water inflow from northeast to southwest in Lake Caohai determined the spatiotemporal distribution of pelagic Microcystis.Benthic Microcystis was mainly distributed in the northeastern region in summer,occupied the lake center in autumn and then occupied the southeastern region in winter,determined by the sedimentation of pelagic Microcystis and the death of benthic Microcystis.Small colonies(20-60μm)overwintered more easily in both water column and sediment.The concentrations of intracellular toxin of benthic Microcystis were observed to be significantly higher than those of pelagic Microcystis.This might be because Microcystis synthesized large amount of mcs to acclimate to an unfavorable benthic environment.This knowledge on the dynamics of Microcystis expands our understanding of mechanisms underpinning the formation of Microcystis blooms.

关键词： Spatiotemporal dynamics Pelagic Microcystis Benthic Microcystis Cell abundance Colony size Intracellular mcs

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World Journal of Gastroenterology 2012年第36期18卷 5114-5121页

作者： Pei-Xian Chen Lu-Nan Yan Wen-Tao Wang Department of Liver and Vascular Surgery West China Hospital of Sichuan University Chengdu 610041 Sichuan Province China Department of Liver and Vascular Surgery West China Hospital of Sichuan University Chengdu 610041 Si- chuan Province China

AIM:To investigate health-related quality of life(HRQoL) and psychological outcomes in 256 adults who had undergone liver transplantation(LT).METHODS:A stratified random sampling method was used in this follow-up multicenter study to select a representative sample of recipients undergoing either living donor liver transplantation(LDLT) or deceased donor liver transplantation(DDLT).HRQoL was measured by using the Chinese version of Medical Outcome Study Short Form-36(SF-36),and psychological outcomes by using the beck anxiety inventory(BAI) and the self-rating depression scale(SDS).Clinical and demographic data were collected from the records of the Chinese Liver Transplant Registry and via questionnaires.RESULTS:A total of 256 patients were sampled,including 66(25.8%) receiving LDLT and 190(74.2%) undergoing DDLT;15(5.9%) recipients had anxiety and four(1.6%) developed severe depression after the operation.Compared with LDLT recipients,DDLT patients had higher scores in general health(60.33 ± 16.97 vs 66.86 ± 18.42,P = 0.012),role-physical(63.64 ± 42.55 vs 74.47 ± 36.46,P = 0.048),roleemotional(61.11 ± 44.37 vs 78.95 ± 34.31,P = 0.001),social functioning(78.60 ± 22.76 vs 88.16 ± 21.85,P = 0.003),vitality(70.30 ± 15.76 vs 75.95 ± 16.40,P = 0.016),mental health(65.88 ± 12.94 vs 71.85 ± 15.45,P = 0.005),physical component summary scale(PCS,60.07 ± 7.36 vs 62.58 ± 6.88,P = 0.013) and mental component summary scale(mcs,52.65 ± 7.66 vs 55.95 ± 10.14,P = 0.016).Recipients > 45 years old at the time of transplant scored higher in vitality(77.33 ± 15.64 vs 72.52 ± 16.66,P = 0.020),mental health(73.64 ± 15.06 vs 68.00 ± 14.65,P = 0.003) and mcs(56.61 ± 10.00 vs 54.05 ± 9.30,P = 0.037) than those aged ≤ 45 years.mcs was poorer in recipients with than in those without complications(52.92 ± 12.21 vs 56.06 ± 8.16,P = 0.017).Regarding mcs(55.10 ± 9.66 vs 50.0 ± 10.0,P < 0.05) and PCS(61.93 ± 7.08 vs 50.0 ± 10.0,P < 0.05),recipients scored better than the Sichuan general and had improved overall QoL compared to patients with chr

关键词：心理健康生活质量肝移植收件人分层随机抽样物理作用人口统计学 mcs

Performance analysis of microcantilever array sensing

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Science China(Technological Sciences) 2017年第11期60卷 1674-1680页

作者： ZHOU XiaRong LIU Hong WU ShangQuan ZHANG QingChuan WU XiaoPing Key Laboratory of Mechanical Behavior and Design of Material Chinese Academy of SciencesDepartment of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China Department of ChemicalPhysics University of Seienee and Technology of ChinaHefei 230026China

Array sensing is increasingly important in the development of microcantilever(MC) sensors, and response consistency is the foundation for MC array sensing. In the present work, we investigated the response consistency of MC array sensing. The responses of two types of commercially available MC arrays were studied under conditions of temperature change, solution replacement and biochemical molecular interaction. For the thermal response, the deflections of both arrays were found to be proportional to temperature, and the responses of the mcs in both arrays were consistent with each other. The thermal response sensitivity for each MC during temperature increase and decrease also showed good consistency. Moreover, the MC array showed good consistency for the response induced by solution replacement. Finally, we also demonstrated that the MC array had good consistency in biochemical detection, exemplified by aflatoxin antibody-anti gen binding. The good response consistency makes this technology reliable and accurate for biochemical sensing.

关键词：传感阵列微悬臂梁传感器性能分析分子相互作用生化检测温度变化 mcs

桔梗萜类合成途径Pgmcs和PgHDR基因克隆与原核表达分析

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植物生理学报 2022年第3期58卷 533-542页

作者：李景刘梦丽余函纹周卓常相伟王举涛查良平桂双英安徽中医药大学药学院合肥230012 安徽省中医药科学院中药资源保护与开发研究所合肥230012 安徽省中医药科学院药物制剂研究所合肥230012 安徽省教育厅现代药物制剂工程技术研究中心合肥230012 药物制剂技术与应用安徽省重点实验室合肥230012

为了研究桔梗三萜类化合物生物合成途径中的关键酶,根据桔梗转录组数据中的基因序列信息,通过RT-PCR方法从桔梗根中克隆得到了2-C-甲基-D-赤藓糖醇2,4-环二磷酸合酶(2-C-methyl-D-erythritol2,4-cyclodiphosphate synthase,mcs)和1-羟基... 详细信息

为了研究桔梗三萜类化合物生物合成途径中的关键酶,根据桔梗转录组数据中的基因序列信息,通过RT-PCR方法从桔梗根中克隆得到了2-C-甲基-D-赤藓糖醇2,4-环二磷酸合酶(2-C-methyl-D-erythritol2,4-cyclodiphosphate synthase,mcs)和1-羟基-2-甲基-2-(E)-丁烯基4-二磷酸还原酶[1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase,HDR]基因Pgmcs和PgHDR,进行序列分析和原核表达分析。结果表明Pgmcs和PgHDR的开放阅读框(ORF)长度分别为738和1416 bp,分别编码245和471个氨基酸,相对分子质量分别为26277.53和52984.17;Pgmcs和PgHDR蛋白理论等电点分别为7.71和5.92。Pgmcs具有PLN02862(MECDP合酶)家族的保守结构域,PgHDR具有PLN02821(HMBPP还原酶)家族的保守结构域。原核表达结果显示,IPTG均可成功诱导目的蛋白表达,分子质量分别为26和60 kDa。基因表达结果显示,Pgmcs和PgHDR基因的表达水平在叶中最高,其次是茎和根。本文首次克隆并分析了桔梗Pgmcs和PgHDR基因,成功建立原核表达体系,为进一步研究桔梗三萜类化合物生物合成的分子机制提供理论依据。

关键词：桔梗 mcs HDR 基因克隆原核表达

Enhanced PSO Based Energy-Efficient Resource Allocation and CQI Based mcs Selection in LTE-A Heterogeneous System

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China Communications 2016年第11期13卷 197-204页

作者： Jianbo Du Liqiang Zhao Jie Feng Jie Xin Yong Wang State Key Laboratory of Integrated Service Networks Xidian University

In order to maximize system energy efficiency(EE) under user quality of service(Qo S) restraints in Long Term Evolution-Advanced(LTE-A) networks,a constrained joint resource optimization allocation scheme is presented,which is NP-hard. Hence,we divide it into three sub-problems to reduce computation complexity,i.e.,the resource block(RB) allocation,the power distribution,and the modulation and coding scheme(mcs) assignment for user codewords. Then an enhanced heuristic approach GAPSO is proposed and is adopted in the RB and power allocation respectively to reduce computational complexity further on. Moreover,a novel mcs allocation scheme is put forward,which could make a good balance between the system reliability and availability under different channel conditions. Simulation results show that the proposed GAPSO could achieve better performance in convergence speed and global optimum searching,and that the joint resource allocation scheme could improve energy efficiency effectively under user Qo S requirements.

关键词：资源分配异构系统 mcs 能量有效增强算法 CQI 计算复杂度能源效率

Optimizing the Gabor Bandwidth of satellite navigation signals by mcs signal expression

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Science China(Physics,Mechanics & Astronomy) 2011年第6期54卷 1077-1082页

作者： ZHANG XiaoMing YAO Zheng LU MingQuan Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing Global Information Center Beijing 100094China

Satellite navigation is playing an important role in social life.The performances of the services a navigation system provides are the concern of the builders and users.The signal structure determines the inherent ability of a satellite navigation system to provide these services.Therefore,it is necessary and reasonable to optimize the signal in the initial design.The waveforms of signals in satellite navigation chips are an important aspect of the signal's structure,which impact the characteristics of the autocorrelation function and power spectrum in the time domain and frequency domain.The range accuracy of a navigation system is usually described by its Gabor Bandwidth.The Gabor Bandwidth of the Binary Offset Carrier (BOC) modulation in next-generation GNSS signal systems is not optimal.This paper presents a signal expression based on Multilevel Coded Symbol (mcs) signals,which can describe the fine structure of navigation signals.With this expression,we can optimize the Gabor Bandwidth of the signal,and find out the corresponding mcs vector and chip waveform,so as to get higher range accuracy.The method in this paper,in theory,is of great value in the design of next-generation navigation signals.

关键词：卫星导航信号 Gabor 带宽优化 mcs 卫星导航系统全球导航卫星系统信号结构波形信号