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The Superiorities of Bayes Linear Unbiased Estimator in Multivariate Linear Models

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Acta Mathematicae Applicatae Sinica 2012年第2期28卷 383-394页

作者： wei-ping ZHANG Lai-sheng wei Yu chen Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China

In this article, the Bayes linear unbiased estimator （BALUE） of parameters is derived for the multivariate linear models. The superiorities of the BALUE over the least square estimator （LSE） is studied in terms of... 详细信息

关键词： multivariate linear models Bayes linear unbiased estimator least square estimator mean squareerror matrix criterion Bayesian Pitman closeness criterion

Precipitate Behavior in Fe–20Cr–30Ni–2Nb Austenitic Heat-Resistant Steel

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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 424-429页

作者： Hiroki Ishikawa Chi Zhang sheng-wei chen Zhi-Gang Yang School of Materials Science and Engineering Tsinghua University Department of Chemistry and Materials Science Tokyo Institute of Technology

In this study, the precipitation behavior of a new austenitic heat-resistant steel （Fe-20Cr-30Ni-2Nb, in at%） was investigated. The effects of alloying addition of boron （B） and lanthanum （La） on the microstructure of the austenitic steel were scrutinized using SEM, EPMA, TEM, and XRD. The results showed that the addition of B enhanced the precipitation of bar-type Laves phase. A small precipitate with high La concentration was observed at the grain boundary in the alloy without aging; similar precipitates without La also presented in region adjacent to the La single phase. This result indicates that La can exist independently and does not contribute to the formation of new compounds. However, in both B- and La-modified alloy, B appeared in the precipitate free zone. In the alloy containing both B and La, only Fe2Nb Laves- phase precipitates, as indicated by the XRD result.

关键词： Precipitation free zone Grain boundary Phase transformation Microstructure Fe-20Cr-30Ni-2Nb austenitic heat-resistant steel

Observer-based Adaptive Iterative Learning Control for Nonlinear Systems with Time-varying Delays

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International Journal of Automation and computing 2010年第4期7卷 438-446页

作者： wei-sheng chen Rui-Hong Li Jing Li Department of Applied Mathematics Xidian University X{an 710071 PRC

An observer-based adaptive iterative learning control （AILC） scheme is developed for a class of nonlinear systems with unknown time-varying parameters and unknown time-varying delays. The linear matrix inequality （LMI） method is employed to design the nonlinear observer. The designed controller contains a proportional-integral-derivative （PID） feedback term in time domain. The learning law of unknown constant parameter is differential-difference-type, and the learning law of unknown time-varying parameter is difference-type. It is assumed that the unknown delay-dependent uncertainty is nonlinearly parameterized. By constructing a Lyapunov-Krasovskii-like composite energy function （CEF）, we prove the boundedness of all closed-loop signals and the convergence of tracking error. A simulation example is provided to illustrate the effectiveness of the control algorithm proposed in this paper.

关键词： Adaptive iterative learning control (AILC) nonlinearly parameterized systems time-varying delays Lyapunov- Krasovskii-like composite energy function.

The first experience of multi-gripper robot assisted percutaneous coronary intervention in complex coronary lesions

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Journal of Geriatric Cardiology 2023年第8期20卷 608-611页

作者： Pan LI Liang ZHANG Bo LI wei-Po chen wei-sheng chen Zhi-Fu GUO Bi-Li ZHANG Department of Cardiology Changhai HospitalNaval Medical UniversityShanghaiChina Department of Cardiology Shanghai 411 HospitalChina RongTong Medical Healthcare Group Co.Ltd.ShanghaiChina

With advances in the field of interventional cardiology,percutaneous coronary intervention(PCI)has become one of the main treatment methods for patients with coronary artery disease in clinical practice.^([1])Routine interventional therapy is performed under fluoroscopic guidance,and interventional cardiologists are therefore often exposed to *** a result,the risks of cancer,cataract,hair loss and loss of skin pigmentation will be significantly incre-ased after long-term radiation exposure.

关键词： coronary percutaneous lesions

Adaptive Output-feedback Regulation for Nonlinear Delayed Systems Using Neural Network

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International Journal of Automation and computing 2008年第1期5卷 103-108页

作者： wei-sheng chen Jun-Min Li Department of Applied Mathematics,Xidian University,Xi′an 710071,PRC Department of Applied Mathematics Xidian University Xi’an PRC

A novel adaptive neural network （NN） output-feedback regulation algorithm for a class of nonlinear time-varying timedelay systems is proposed. Both the designed observer and controller are independent of time delay. Different from the existing results, where the upper bounding functions of time-delay terms are assumed to be known, we only use an NN to compensate for all unknown upper bounding functions without that assumption. The proposed design method is proved to be able to guarantee semi-global uniform ultimate boundedness of all the signals in the closed system, and the system output is proved to converge to a small neighborhood of the origin. The simulation results verify the effectiveness of the control scheme.

关键词： Adaptive neural network (NN) output-feedback nonlinear time-delay systems backstepping

多孔苯乙烯-二乙烯基苯共聚物的制备与孔结构

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高分子材料科学与工程 2010年第11期26卷 71-74页

作者：胡友根周志平盛维琛江苏大学材料科学与工程学院江苏镇江212013

以甲苯和正庚烷为混合致孔剂,悬浮法制备多孔苯乙烯-二乙烯基苯共聚物(St-DVB)。在77K低温下,采用氮气吸附法测定了多孔St-DVB共聚物的氮气吸附-脱附等温线。通过改变交联度和致孔剂组分(甲苯与正庚烷配比),研究了它们对共聚物微观孔结... 详细信息

以甲苯和正庚烷为混合致孔剂,悬浮法制备多孔苯乙烯-二乙烯基苯共聚物(St-DVB)。在77K低温下,采用氮气吸附法测定了多孔St-DVB共聚物的氮气吸附-脱附等温线。通过改变交联度和致孔剂组分(甲苯与正庚烷配比),研究了它们对共聚物微观孔结构的影响。结果表明,共聚物的孔体积和平均孔径随甲苯与正庚烷配比的增大而减小,比表面积和微孔体积在甲苯与正庚烷配比为1∶1时最大。交联度对共聚物孔结构的影响显著,比表面积和孔体积随交联度的增大而明显增加,平均孔径随交联度的增大而减小。

关键词：多孔苯乙烯-二乙烯基苯共聚物氮气吸附-脱附等温线比表面积孔体积平均孔径

AB_g型缩聚形成的超支化聚合物的支化度与分子形态

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化学学报 2007年第20期65卷 2343-2348页

作者：周志平孔祥涛盛维琛朱申敏颜德岳江苏大学材料科学与工程学院镇江212013 上海交通大学金属基复合材料国家重点实验室上海200030

用聚合反应动力学模型,详细分析了ABg型缩聚体系中各种结构单元的演变,对超支化聚合物支化度的各种定义作了比较,并对ABg型反应体系的支化度提出了一个改进的定义,使得支化度随g的增加而增加,当g从2增加到无穷大,最大支化度相应地从0.5... 详细信息

用聚合反应动力学模型,详细分析了ABg型缩聚体系中各种结构单元的演变,对超支化聚合物支化度的各种定义作了比较,并对ABg型反应体系的支化度提出了一个改进的定义,使得支化度随g的增加而增加,当g从2增加到无穷大,最大支化度相应地从0.5增加到1-e-1.对均方回转半径的数值计算表明,在确定的A基团转化率(x),z-均均方回转半径几乎与g无关,当x=0.999时,随着g从2增加到无穷大,z-均回转半径只增加0.1%.但是,同样的条件下,z-均聚合度增加到2倍.这一现象表明在任何指定的A转化率,ABg型缩聚中形成的超支化聚合物的分子轮廓与g无关,随着g增大而在超支化聚合物中增加的结构单元(或聚合度)必定分布在分子内部.

关键词：超支化聚合物支化度动力学模型

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金颗粒掺杂对有机-硅光伏电池性能的影响

精细化工 2018年第3期35卷 449-455页

作者：申小娟陈玲钟敏张侃盛维琛江苏大学材料科学与工程学院

将金纳米颗粒（Au NPs）掺入导电聚合物聚3,4-乙烯二氧噻吩∶聚苯乙烯磺酸（PEDOT∶PSS）薄膜中,制备了有机-硅杂化光伏电池。利用TEM和SEM对Au NPs及其掺杂的有机膜进行了表征。考察了金纳米颗粒对有机-硅杂化光伏电池光学和电学性能... 详细信息

将金纳米颗粒（Au NPs）掺入导电聚合物聚3,4-乙烯二氧噻吩∶聚苯乙烯磺酸（PEDOT∶PSS）薄膜中,制备了有机-硅杂化光伏电池。利用TEM和SEM对Au NPs及其掺杂的有机膜进行了表征。考察了金纳米颗粒对有机-硅杂化光伏电池光学和电学性能的影响。电池的电流密度-电压曲线（J-V）、外量子效率（EQE）和电容-电压曲线（C-V）测试结果表明,Au NPs的引入提高了电池的光电性能,与纯PEDOT∶PSS-硅电池相比,掺入金纳米颗粒制备的杂化光伏电池的光电转化效率（PCE）提高了24%,达到12.87%;在金纳米颗粒的等离子共振区域,电池对光的反射性能降低;当V（金纳米颗粒）∶V（PEDOT∶PSS）=0.15∶1.0时,膜的导电率由560 S/cm增加到860S/cm、PEDOT∶PSS-硅光伏电池的内建电场（Vbi）由0.68 V增加到0.78 V,金纳米颗粒与PEDOT∶PSS共同作用,极大地减少了电荷在传输过程中的损失,提高了电池中电荷的传输和收集效率。

关键词：金纳米颗粒聚3 4-乙烯二氧噻吩∶聚苯乙烯磺酸硅基杂化光伏电池表面等离子体效应内建电场有机电化学与工业

Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior

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Neural Regeneration Research 2025年第1期20卷 159-173页

作者： Man Han Deyang Zeng wei Tan Xingxing chen Shuyuan Bai Qiong Wu Yushan chen Zhen wei Yufei Mei Yan Zeng Brain Science and Advanced Technology Institute Wuhan University of Science and TechnologyWuhanHubei ProvinceChina Geriatric Hospital Affiliated to Wuhan University of Science and Technology WuhanHubei ProvinceChina School of Public Health Wuhan University of Science and TechnologyWuhanHubei ProvinceChina

Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral *** studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and *** how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress *** this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of *** focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine *** determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic ***,BDNF might be a biological indicator regulating stress-related processes in various brain regions.

关键词： amygdala chronic mild stress chronic social defeat stress corticolimbic system depression hippocampus medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area