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控制理论与应用（英文版） 2013年第2期11卷 180-185页

作者： Ruijie zhao Xiaoping LAI School of Mechanical Electrical and Information Engineering Shandong University at Weihai Institute of Information and Control Hangzhou Dianzi University

This paper focuses on the design of two-dimensional （2D） quadrantally symmetric finite impulse response （FIR） filters, and presents three very efficient algorithms for the weighted least squares （WLS） design with a weight matrix that assigns four different weights to four different frequency bands. The first algorithm seeks for iterative solutions to the matrix equation describing the optimality condition of the design problem. The second algorithm aims at the limit solution of the solution sequence to the first algorithm, analytically obtained by using matrix diagonalization techniques. The third algorithm belongs to the category of iterative reweighting techniques. It uses the second algorithm as its iteration core, and aims at reducing the maximum magnitude error of the filter by iteratively adjusting the four entry values of the weight matrix. Design examples are provided to demonstrate the performance of the proposed algorithms.

关键词： 2D FIR filters Diagonalization Quadrantal symmetry WLS design

Regulation of hematopoietic stem cells in the niche

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Science China(Life Sciences) 2015年第12期58卷 1209-1215页

作者： zhao Meng LI LinHeng Stowers Institute for Medical Research Department of Pathology & Laboratory Medicine University of Kansas Medical Center

Hematopoiesis provides a suitable model for understanding adult stem cells and their niche. Hematopoietic stem cells(HSCs) continuously produce blood cells through orchestrated proliferation, self-renewal, and differentiation in the bone marrow(BM). Within the BM exists a highly organized microenvironment termed "niche" where stem cells reside and are maintained. HSC niche is the first evidence that a microenvironment contributes to protecting stem cell integrity and functionality in mammals. Although multiple models exist, recent progress has principally elucidated the cellular complexity of the HSC niche that maintains and regulates HSCs in BM. Here we introduce the development and summarize the achievements of HSC niche studies.

关键词： hematopoietic stem cells niche regeneration

On the Cauchy Problem of Evolution p-Laplacian Equation with Nonlinear Gradient Term

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Chinese Annals of Mathematics,Series B 2009年第1期30卷 1-16页

作者： Mingyu CHEN Junning zhao School of Science Quanzhou Normal University Quanzhou 362050Fujian China Department of Mathematics Xiamen University Xiamen 361005 Fujian China

The authors study the existence of solution to p-Laplacian equation with nonlinear forcing term under optimal assumptions on the initial data, which are assumed to be measures. The existence of local solution is obtai... 详细信息

关键词： p-Laplacian equation Nonlinear gradient term Measures initial data Local solution

Evaluation of earthquake signal characteristics for early warning

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 435-443页

作者： Kong Qingkai zhao Ming Building Engineering Department Tongji UniversityShanghai 200092China

This paper evaluates different characteristics for earthquake early warning. The scaling relationships between magnitude, epicenter distance and calculated parameters are derived from earthquake event data fi＇om USGS. The standard STA/LTA method is modified by adding two new parameters to eliminate the effects of the spike-type noise and small pulsetype noise ahead of the onset of the P-wave. After the detection of the P-wave, the algorithm extracts 12 kinds of parameters from the first 3 seconds of the P-wave. Then stepwise regression analysis of these parameters is performed to estimate the epicentral distance and magnitude. Six different parameters are selected to estimate the epicentral distance, and the median error for all 419 estimates is 16.5 krn. Four parameters are optimally combined to estimate the magnitude, and the mean error for all events is 0.0 magnitude units, with a standard deviation of 0.5. Finally, based on the estimation results, additional work is proposed to improve the accuracy of the results.

关键词： earthquake early warning epicentral distance estimation magnitude estimation

Robust current and speed control of a permanent magnet synchronous motor using SMC and ADRC

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Control Theory and Technology 2019年第2期17卷 190-199页

作者： Yang zhao Lili DONG Department of Electrical Engineering and Computer Science Cleveland State UniversityClevelandOH 44115U.S.A.

A second-order ordinary differential equation model is originally constructed for the phase q current system of a permanent magnet synchronous motor(PMSM).The phase q current model contains the effect of a counter electromotive force(CEMF),which introduces nonlinearity to the *** order to compensate the nonlinearity and system uncertainties,a traditional sliding mode controller(SMC)combined with a low-pass filter(also known as a modified SMC)is designed on the phase q current *** low-pass filter overcomes chattering effects in control efforts,and hence improves the performance of the *** phase q current control system is proved to be stable using Lyapunov *** addition,an alternative activedisturbance rejection controller(ADRC)with a reduced-order extended state observer(ESO)is applied to control the speed output of *** SMC and ADRC are simulated on the PMSM *** simulation results demonstrate the effectiveness of these two controllers in successfully driving the current and speed outputs to desired values despite load disturbances and system uncertainties.

关键词： PMSM SMC ADRC robustness external disturbance system uncertainty

Multi-objective Optimal Operation of Centralized Battery Swap Charging System with Photovoltaic

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Journal of Modern Power Systems and Clean Energy 2022年第1期10卷 149-162页

作者： Yuanzheng Li Yihan Cai Tianyang zhao Yun Liu Jian Wang Lei Wu Yong zhao School of Artificial Intelligence and Automation Ministry of Education Key Laboratory of Image Processing and Intelligence ControlHuazhong University of Science and TechnologyWuhanChina School of Electrical and Electronic Engineering Nanyang Technological UniversitySingaporeSingapore College of Mechatronics and Control Engineering Shenzhen UniversityShenzhenChina Department of Electrical&Computer Engineering Stevens Institute of TechnologyHobokenUSA

Electric vehicles(EVs)are widely deployed throughout the world,and photovoltaic(PV)charging stations have emerged for satisfying the charging demands of EV *** paper proposes a multi-objective optimal operation method for the centralized battery swap charging system(CBSCS),in order to enhance the economic efficiency while reducing its adverse effects on power *** proposed method involves a multi-objective optimization scheduling model,which minimizes the total operation cost and smoothes load fluctuations,***,we modify a recently proposed multi-objective optimization algorithm of non-sorting genetic algorithm III(NSGA-III)for solving this scheduling ***,simulation studies verify the effectiveness of the proposed multi-objective operation method.

关键词： Multi-objective optimization electric vehicle battery swap charging system scheduling photovoltaic

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梯度功能材料非定常热传导的形状效应

机械工程学报 2008年第12期44卷 30-34页

作者：赵军艾兴李艳征山东大学机械工程学院济南250061

采用分离变量法和变量代换法,推导出无限大平板、无限长圆柱体和圆球体3种形状的梯度功能材料构件在第三类边界条件下的量纲一非定常温度场的解析解。3种形状的梯度功能材料构件的组分和热-物理性能分别服从平面对称、轴对称和球对称分... 详细信息

采用分离变量法和变量代换法,推导出无限大平板、无限长圆柱体和圆球体3种形状的梯度功能材料构件在第三类边界条件下的量纲一非定常温度场的解析解。3种形状的梯度功能材料构件的组分和热-物理性能分别服从平面对称、轴对称和球对称分布规律。通过数值计算并与无限大平板、无限长圆柱体和圆球体3种形状的均质构件对比,研究梯度功能材料构件形状以及热-物理性能分布对非定常热传导的影响。计算结果表明,梯度功能材料构件的非定常热传导具有与均质构件相似的形状效应,即圆球体的温度传播速度最快,而无限大平板的温度传播速度最慢。由表及里增大梯度功能材料构件的热导率和热扩散率,可提高温度传播速度。

关键词：梯度功能材料非定常热传导形状效应变热物性

Predicting various outcomes of post-resuscitation comatose survivors： PRCSs Prognostication Score

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Journal of Geriatric Cardiology 2009年第4期6卷 204-208页

作者： Xin-Ke Meng Zhi-Gang zhao Guang-Fen Wu Gang Wei Sun-Ting Su De-Hong Liu Xiao-Ying zhen Shao-Quan Shi Department of Emergency Medicine The Second Shenzhen People＇s Hospital No.3002 SunGang West Road Shenzhen 518020 China Department of Gynecology and Obstetrics The Fifth Affiliated Hospital Sun Yat-sen University Guangzhou 510000 China

Objective To develop a tool capable of early and exactly predicting various outcomes in comatose survivors who restore spontaneous circulation after cardiopulmonary resuscitation （CPR） and validate its performance. Methods Variables that were both readily available and predictive of outcomes were identified by systematically reviewing published literature on resuscitation. A value was assigned to these variables. We used these variables in combination with APACHE II score to devise a multifactorial prediction score system, which we called PRCSs Prognostication Score （PRCSs-PS）. Outcomes in 115 hospitalized comatose survivors after CPR were retrospectively reviewed using PRCSs-PS. Score of patients with different outcomes was compared. The area under the receiver- operating characteristic （ROC） curve was determined to evaluate performance of this tool to identify patients with a poor outcome （CPC4 and 5） and other outcomes （CPC1, 2, and 3）. Results There were differences of PRCSs-PS score among multiple groups with five different outcomes （CPC 1-5）（F=65.91, P=0.000）. Pairwise groups with different CPC were compared： no significant difference was noted between CPC1 and CPC2 （12.41±6.49 vs 17.38±6.91,P=0.092）, but difference between other pairwise CPC groups was statistically significant （CPC2 vs CPC3：17.38±6.91 vs 24.50±5.80, P=0.041, CPC3 vs CPC4：24.50±5.80 vs 32.29±5.24, P=0.006）. The performance of PRCSs-PS to discriminate patients with a poor outcome from patients with other outcomes went as follows： it had 100% sensitivity, 78.6% specificity, and 178.6 diagnostic index at the score cut-off22.5; it had 77.8% sensitivity, 100% specificity and 176.4 diagnostic index at the score cut-off32.5. Score 23 and 33 were two key cut-offpoints. The area under the ROC curve was 0.968, showing excellent discrimination. Conclusions The final outcomes in post-resuscitation comatose survivors can be accurately predicted using PRCSs-PS Score.

关键词： cardiopulmonary resuscitation (CPR) coma prognosis score

Single-cell RNA sequencing reveals Nestin+active neural stem cells outside the central canal after spinal cord injury

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Science China(Life Sciences) 2022年第2期65卷 295-308页

作者： Muya Shu Xiaoyu Xue Hu Nie Xianming Wu Minghan Sun Lianyong Qiao xing Li Bai Xu Zhifeng Xiao Yannan zhao Yongheng Fan Bing Chen Jixiang Zhang Ya Shi Yaming Yang Falong Lu Jianwu Dai State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100080China University of the Chinese Academy of Sciences Beijing 100101China Key Laboratory of Organ Injury Aging and Regenerative Medicine of Hunan ProvinceChangsha 410008China

Neural stem cells(NSCs)in the spinal cord hold great potential for repair after spinal cord injury(SCI).The ependyma in the central canal(CC)region has been considered as the NSCs source in the spinal ***,the ependyma function as NSCs after SCI is still under *** used Nestin as a marker to isolate potential NSCs and their immediate progeny,and characterized the cells before and after SCI by single-cell RNA-sequencing(scRNA-seq).We identified two subgroups of NSCs:the subgroup located within the CC cannot prime to active NSCs after SCI,while the subgroup located outside the CC were activated and exhibited the active NSCs properties after *** demonstrated the comprehensive dynamic transcriptome of NSCs from quiescent to active NSCs after *** study reveals that Nestin+cells outside CC were NSCs that activated upon SCI and may thus serve as endogenous NSCs for regenerative treatment of SCI in the future.

关键词： neural stem cell Nestin scRNA-seq Smart-seq2 ependymal cell

Extracellular vesicles derived from mesenchymal stem cells mediate extracellular matrix remodeling in osteoarthritis through the transport of microRNA-29a

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World Journal of Stem Cells 2024年第2期16卷 191-206页

作者： Fan Yang Wan-Qi Xiong Chen-Zhi Li Ming-Jian Wu Xiu-Zhi Zhang Chun-Xiao Ran zhen-Hao Li Yan Cui Bao-Yi Liu De-Wei zhao Department of Orthopedics Affiliated Zhongshan Hospital of Dalian UniversityDalian 116001Liaoning ProvinceChina

BACKGROUND Knee osteoarthritis(KOA)is a common orthopedic condition with an uncertain etiology,possibly involving genetics and *** like changes in chondrocyte microenvironment,oxidative stress,inflammation,and immune responses affect KOA ***-stage treatment options primarily target symptom *** stem cells(MSCs)show promise for treatment,despite *** research highlights microRNAs(miRNAs)within MSC-released extracellular vesicles that can potentially promote cartilage regeneration and hinder KOA *** suggests exosomes(Exos)as a promising avenue for future *** these findings emphasize the need for effective KOA progression management,further safety and efficacy validation for Exos is *** To explore miR-29a’s role in KOA,we’ll create miR-29a-loaded vesicles,testing for early treatment in rat *** Extraction of bone marrow MSC-derived extracellular vesicles,preparation of engineered vesicles loaded with miR-29a using ultrasonication,and identification using quantitative reverse transcription polymerase chain reaction;after establi-shing a rat model of KOA,rats were randomly divided into three groups:Blank control group injected with saline,normal extracellular vesicle group injected with normal extracellular vesicle suspension,and engineered extrace-llular vesicle group injected with engineered extracellular vesicle *** three groups evaluation,histological detection,and immunohistochemical detection to compare and evaluate the progress of various forms of *** General behavioral observation results showed that the extracellular vesicle group and engineered extracellular vesicle group had better performance in all four indicators of pain,gait,joint mobility,and swelling compared to the blank control ***,the engineered extracellular vesicle group had better pain relief at 4 wk and better knee joint mobility at 8 wk compared to the nor

关键词： Exosomes Osteoarthritis Mesenchymal stem cells MicroRNA-29a Intra-articular injection