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Quantile-based optimization under uncertainties for complex engineering structures using an active learning basis-adaptive PC-Kriging model

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Chinese Journal of Aeronautics 2025年第1期38卷 340-352页

作者： Yulian GONG Jianguo zhang Dan XU ying HUANG School of Reliability and Systems Engineering Beihang UniversityBeijing 100191China

The Reliability-Based Design Optimization(RBDO)of complex engineering structures considering uncertainties has problems of being high-dimensional,highly nonlinear,and timeconsuming,which requires a significant amount of sampling simulation *** this paper,a basis-adaptive Polynomial Chaos(PC)-Kriging surrogate model is proposed,in order to relieve the computational burden and enhance the predictive accuracy of a *** active learning basis-adaptive PC-Kriging model is combined with a quantile-based RBDO ***,five engineering cases have been implemented,including a benchmark RBDO problem,three high-dimensional explicit problems,and a high-dimensional implicit *** with Support Vector Regression(SVR),Kriging,and polynomial chaos expansion models,results show that the proposed basis-adaptive PC-Kriging model is more accurate and efficient for RBDO problems of complex engineering structures.

关键词： Reliability-based design optimization Quantile-based Basis-adaptive PC-Kriging Complex engineering structures Active learning Uncertainty

Occurrence of phthalate esters in the yellow and Yangtze rivers of china:Risk assessment and source apportionment

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Journal of Environmental Sciences 2025年第3期149卷 628-637页

作者： Qinkui Miao wenxiang Ji Huiyu Dong ying zhang College of Environmental Science and Engineering Nankai UniversityTianjin 300350China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Phthalate esters(PAEs),recognized as endocrine disruptors,are released into the environment during usage,thereby exerting adverse ecological *** study investigates the occurrence,sources,and risk assessment of PAEs in surface water obtained from 36 sampling points within the Yellow River and Yangtze River *** total concentration of PAEs in the Yellow River spans from124.5 to 836.5 ng/L,with Dimethyl phthalate(DMP)(75.4±102.7 ng/L)and Diisobutyl phthalate(DiBP)(263.4±103.1 ng/L)emerging as the predominant *** exhibit a pattern of upstream(512.9±202.1 ng/L)>midstream(344.5±135.3 ng/L)>downstream(177.8±46.7 ng/L).In the Yangtze River,the total concentration ranges from 81.9 to 441.6 ng/L,with DMP(46.1±23.4 ng/L),Diethyl phthalate(DEP)(93.3±45.2 ng/L),and DiBP(174.2±67.6 ng/L)as the primary *** levels follow a midstream(324.8±107.3 ng/L)>upstream(200.8±51.8 ng/L)>downstream(165.8±71.6 ng/L)*** should be directed towards the moderate ecological risks of DiBP in the upstream of HH,and both the upstream and midstream of CJ need consideration for the moderate ecological risks associated with Di-n-octyl phthalate(DNOP).Conversely,in other regions,the associated risk with PAEs is either low or *** main source of PAEs in Yellow River is attributed to the release of construction land,while in the Yangtze River Basin,it stems from the accumulation of pollutants in lakes and forests discharged into the *** findings are instrumental for pinpointing sources of PAEs pollution and formulating control strategies in the Yellow and Yangtze Rivers,providing valuable insights for global PAEs research in other major rivers.

关键词： Phthalates Spatial variation Potential sources Risk assessment

Adsorption of typical NDMA precursors by superfine powdered activated carbon:Critical role of particle size reduction

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Journal of Environmental Sciences 2025年第1期147卷 101-113页

作者： ying Wang Zhichen zhang Zhihang Yin Jun Wang Xiaojian zhang Chao Chen State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Research Institute for Environmental Innovation(Suzhou) TsinghuaSuzhou 215163China

Control of N-nitrosodimethylamine(NDMA)in drinking water could be achieved by removing its precursors as one practical ***,superfine powdered activated carbons with a diameter of about 1μm(SPACs)were successfully prepared by grinding powdered activated carbon(PAC,D50=24.3μm)and applied to remove model NDMA precursors,***(RAN)and nizatidine(NIZ).Results fromgrain diameter experiments demonstrated that the absorption velocity increased dramatically with decreasing particle size,and the maximum increase in k2 was 26.8-folds for RAN and 33.4-folds for ***,kinetic experiments explained that rapid absorption could be attributed to the acceleration of intraparticle diffusion due to the shortening of the diffusion ***,performance comparison experiments suggested that the removal of RAN and NIZ(C_(0)=0.5 mg/L)could reach 61.3%and 60%,respectively,within 5 min,when the dosage of SAPC-1.1(D_(50)=1.1μm)was merely 5 mg/L,while PAC-24.3 could only eliminate 17.5%and 18.6%.The adsorption isotherm was well defined by Langmuir isotherm model,indicating that the adsorption of RAN/NIZ was a monolayer coverage *** adsorption of RAN or NIZ by SAPC-1.1 and PAC-24.3 was strongly pH dependent,and high adsorption capacity could be observed under the condition of pH>pk_(a)+*** coexistence of humic acid(HA)had no significant effect on the adsorption performance because RAN/NIZ may be coupled with HA and removed *** coexistence of anions had little effect on the adsorption *** study is expected to provide an alternative strategy for drinking water safety triggered by NDMA.

关键词： Adsorption NDMA Kinetics Superfine powdered activated carbon Intraparticle diffusion Drinking water

Bistable switch molecule DPACdCl_(4) showing four physical channels and high phase transition temperature

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Chinese Chemical Letters 2025年第1期36卷 591-596页

作者： ying-Yu zhang Jia-Qi Luo Yan Han Wan-ying zhang Yi zhang Hai-Feng Lu Da-Wei Fu Institute for Science and Applications of Molecular Ferroelectrics Key Laboratory of the Ministry of Education for Advanced Catalysis MaterialsZhejiang Normal UniversityJinhua 321004China Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and applications of Molecular FerroelectricsSoutheast UniversityNanjing 211189China

Multiple switchable physical channels within one material or device,encompassing optical,electrical,thermal,and mechanical pathways,can enable multifunctionality in mechanical-thermal-opto-electronic *** integrated encryption and enhanced performance in storage and sensing presents a formidable challenge in the synthesis and functionality of new *** an effort to overcome the complexities associated with these multiple physical functions,this study investigates the large-size crystal of DPACdCl_(4)(DPA=diisopropylammonium),revealing significant features in rare multi-channel *** compound demonstrates the ability to switch between"OFF/0"and"ON/1"states in the mechanical-thermal-opto-electronic ***,DPACd Cl_(4)possesses four switchable physical channels,characterized by a higher phase transition temperature of 440.7 K and a competitive piezo-electric coefficient of 46 pC/***,solid-state NMR analysis indicates that thermally activated molecular vibrations significantly contribute to its multifunctional switching capabilities.

关键词： Organic-inorganic hybrid Phase transition Crystal Perovskite Piezoelectricity

Experimental demonstration of 220-GHz terahertz signals wireless transmission over 4.6 km

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Science China(Information Sciences) 2025年第1期68卷 386-388页

作者： Yi WEI Jianjun YU Mingxu WANG Xiongwei YANG Qiutong zhang Jingwen TAN Bing zhang ying WU Yang HAN Peng TIAN wen ZHOU Kaihui WANG Feng ZHAO State Key Laboratory of ASIC and System Key Laboratory for Information Science of Electromagnetic Waves (MoE)School of Information Science and Technology Fudan University School of Electronic Engineering Xi'an University of Posts and Telecommunications

The advancement of terahertz (THz) communication technology drives the evolution of wireless communication systems,offering novel pathways and technical means for the development of future 6G communication *** wireless communication systems are often constrained by bandwidth limitations of electronic devices in high frequency ***,THz communication technology leverages the characteristics of electromagnetic waves to transcend these limitations,enabling communication athigher frequencies and wider bandwidths.

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A Comparison between Volume Responsiveness Predicted by Changes in Pulse Pressure and by Changes in Stroke Volume Induced by Passive Leg Raising

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麻醉与监护论坛 2011年第2期18卷 114-118,121页

作者： Lei Huang Wei-xing zhang wen-xun Cai ying-qun Cheng ying-xin Lin Department of Intensive Care Unit Peking University Shenzhen Hospital Shenzhen Guangdong 518036 China

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数据仓库技术在昆明电网电量分析中的应用

电网技术 2005年第14期29卷 40-44页

作者：张文英束洪春张叶昆明理工大学电力工程学院云南省昆明市650093 昆明供电局云南省昆明市650011

数据仓库技术对操作型数据转化成全面、集成的信息,以及对海量数据的查询和统计提供了有效的途径。文章在介绍数据仓库、联机分析处理概念和技术的基础上,分析了面向主题的多维数据库的建立和多维视图的展现等技术,针对昆明电网负荷管... 详细信息

数据仓库技术对操作型数据转化成全面、集成的信息,以及对海量数据的查询和统计提供了有效的途径。文章在介绍数据仓库、联机分析处理概念和技术的基础上,分析了面向主题的多维数据库的建立和多维视图的展现等技术,针对昆明电网负荷管理系统,基于微软的SQLServer2000和SQLAnalysisServices2000构建了面向电量主题的数据仓库,在数据可视化方面弥补了AnalysisServices2000的不足。同时讨论了数据仓库技术在完成电量数据的查询、统计、分析、生成各种统计报表方面的具体应用。

关键词：数据仓库电量管理联机分析多维视图数据挖掘电力系统

基于PI3K/Akt信号通路探讨乌梅丸含药血清对胰腺癌细胞增殖、侵袭、迁移和凋亡的影响

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中国实验方剂学杂志 2022年第6期28卷 34-42页

作者：王熙张莹雯湖北中医药大学武汉430061 武汉市中医医院武汉430014 武汉大学中南医院武汉430071

目的:观察乌梅丸含药血清对人胰腺癌SW1990细胞增殖、侵袭、迁移和凋亡的影响,同时探讨其可能的作用机制。方法:制备乌梅丸含药血清,体外培养胰腺癌细胞株SW1990,采用细胞增殖与活性检测(CCK-8)法筛选乌梅丸含药血清最佳作用时间用于后... 详细信息

目的:观察乌梅丸含药血清对人胰腺癌SW1990细胞增殖、侵袭、迁移和凋亡的影响,同时探讨其可能的作用机制。方法:制备乌梅丸含药血清,体外培养胰腺癌细胞株SW1990,采用细胞增殖与活性检测(CCK-8)法筛选乌梅丸含药血清最佳作用时间用于后续实验;将SW1990细胞分为空白组和乌梅丸低、中、高组(含药血清2%、4%、8%),利用平板克隆实验、细胞划痕实验和细胞侵袭实验分别检测其克隆形成、迁移和侵袭能力;流式细胞术检测乌梅丸含药血清对胰腺癌SW1900细胞凋亡的影响;通过蛋白免疫印迹法(Western blot)检测SW1990细胞中凋亡相关蛋白,B细胞淋巴瘤-2(Bcl-2),Bcl-2相关X蛋白(Bax),细胞色素C(Cyt C),活化的半胱氨酸天冬氨酸蛋白水解酶-3(cleaved Caspase-3)、cleaved Caspase-9,磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/Akt)通路中PI3K,磷酸化(p)-PI3K,Akt,磷酸化(p)-Akt蛋白表达水平。结果:与空白组比较,作用72 h,乌梅丸低、中、高组吸光度A显著降低(P<0.01),与乌梅丸低组比较,乌梅丸中、高组A均显著降低(P<0.01),与乌梅丸中组比较,乌梅丸高组A显著降低(P<0.01),说明乌梅丸作用72 h可呈剂量依赖性抑制SW1990细胞增殖能力,药物最佳作用时间为72 h;与空白组比较,乌梅丸低、中、高组SW1990细胞侵袭能力显著减弱(P<0.01),且呈浓度依赖性;与空白组比较,乌梅丸低、中、高组细胞克隆形成能力、迁移能力均有下降(P<0.05,P<0.01),且呈浓度依赖性;与空白组比较,乌梅丸低、中、高组细胞的总凋亡率显著升高(P<0.01),乌梅丸诱导凋亡作用随给药剂量增加而增强;与空白组比较,乌梅丸低、中、高组Bcl-2蛋白表达显著降低(P<0.01),cleaved Caspase-3,cleaved Caspase-9,Cyt C,Bax蛋白表达升高(P<0.05,P<0.01),且呈现出一定的量效关系;与空白组比较,乌梅丸低、中、高组p-PI3K,p-Akt蛋白表达均有减少(P<0.05,P<0.01),且随着剂量的增加,蛋白表达逐渐降低,p-PI3K/PI3K,p-Akt/Akt明显降低(P<0.05,P<0.01),且随着剂量的增加,比值逐渐降低。结论:乌梅丸能明显抑制胰腺癌SW1990细胞的恶性生物学行为,诱导细胞凋亡,其机制可能与抑制PI3K/Akt信号通路,下调PI3K/Akt通路中的蛋白磷酸化水平有关。

关键词：乌梅丸含药血清胰腺癌增殖侵袭转移磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/Akt)信号通路

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控制系统故障检测与诊断技术的最新进展

系统工程与电子技术 2007年第4期29卷 659-664页

作者：张爱玲张文英张端金郑州大学信息工程学院河南郑州450052

对故障检测与诊断(FDD)技术在控制领域的最新进展进行了综述,内容主要包括三类基本方法,即:基于解析模型的FDD、基于信号处理和基于知识的故障检测与诊断方法。重点评述了近年来发展起来的信息融合方法、多Agent方法、鲁棒故障检测、网... 详细信息

对故障检测与诊断(FDD)技术在控制领域的最新进展进行了综述,内容主要包括三类基本方法,即:基于解析模型的FDD、基于信号处理和基于知识的故障检测与诊断方法。重点评述了近年来发展起来的信息融合方法、多Agent方法、鲁棒故障检测、网络控制系统的故障诊断等。最后介绍了故障检测与诊断技术在控制系统中的若干应用成果,并指出尚待解决的主要问题和值得进一步研究的方向。

关键词：控制系统故障检测与诊断解析模型鲁棒性