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Impulsive control of unstable neural networks with unbounded time-varying delays

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Science China(Information Sciences) 2018年第1期61卷 219-232页

作者： Xiaodi LI Shiji song jianhong wu School of Mathematics and Statistics Shandong Normal University Institute of Data Science and Technology Shandong Normal University Department of Automation Tsinghua University Department of Mathematics and Statistics York University

This paper considers the impulsive control of unstable neural networks with unbounded timevarying delays, where the time delays to be addressed include the unbounded discrete time-varying delay and unbounded distributed time-varying delay. By employing impulsive control theory and some analysis techniques, several sufficient conditions ensuring μ-stability, including uniform stability,(global) asymptotical stability, and(global) exponential stability, are derived. It is shown that an unstable delay neural network,especially for the case of unbounded time-varying delays, can be stabilized and has μ-stability via proper impulsive control strategies. Three numerical examples and their simulations are presented to demonstrate the effectiveness of the control strategy.

关键词： unstable neural networks impulsive control unbounded discrete time-varying delay unbounded distributed time-varying delay μ-stability

Enhanced kernel-based fuzzy local information clustering integrating neighborhood membership

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The Journal of China Universities of Posts and Telecommunications 2021年第6期28卷 65-81页

作者： song Yue wu Chengmao Tian Xiaoping song Qiuyu School of Communication and Information Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China School of Electronic and Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

To enhance the segmentation performance and robustness of kernel weighted fuzzy local information C-means(KWFLICM) clustering for image segmentation in the presence of high noise, an improved KWFLICM algorithm aggregating neighborhood membership information is proposed. This algorithm firstly constructs a linear weighted membership function by combining the membership degrees of current pixel and its neighborhood pixels. Then it is normalized to meet the constraint that the sum of membership degree of pixel belonging to different classes is 1. In the end, normalized membership is used to update the clustering centers of KWFLICM algorithm. Experimental results show that the proposed adaptive KWFLICM(AKWFLICM) algorithm outperforms existing state of the art fuzzy clustering-related segmentation algorithms for image with high noise.

关键词： image segmentation fuzzy clustering combined membership degree local information factor

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Theoretical Calculations of Optical Spectra and Their Pressure-Induced Shifts of MgAl_2O_4:Cr^(3+)

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Communications in Theoretical Physics 2008年第5期49卷 1339-1344页

作者： wu Fei ZHANG ji-Ping College of Physical Science and Technology Sichuan University Chengdu 610065 China

The energy levels of spectrum, wavefunetions and crystal-field parameters of MgAl2O4：Cr^3＋ at normal pressure have been calculated by the means of diagonalizing the complete d^3 energy matrix （DCEM）. With these results, the g factor of the ground state at normal pressure and the pressure-induced shift （PS） of the spectra1 levels are also calculated uniformly, and the calculated results are all in good agreement with the experimental ones. And the contributions of various crystal-field parameters to the energy levels at normal pressure and the variational rates of the R1 line shifting with the pressure are calculated, from which the physical origin of the red shift of the R1 line shifting with increasing pressure have been clearly shown.

关键词： crystal fields energy spectrum g factor high-pressure effect

The Maximum Principle for One Kind of Stochastic Optimization Problem and Application in Dynamic Measure of Risk

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2189-2204页

作者： Shao Lin ji Zhen wu School of Mathematics and Systems Science Shandong University Jinan 250100 P. R. China

The authors get a maximum principle for one kind of stochastic optimization problem motivated by dynamic measure of risk. The dynamic measure of risk to an investor in a financial market can be studied in our framewor... 详细信息

关键词： backward stochastic differential equation perturbation method Ekeland's variational principle dynamic measure of risk

Gaussian particle filter based pose and motion estimation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1604-1613页

作者： wu Xue-dong song Zhi-huan State Key Lab. of Industrial Control Technology Institute of Industrial Process Control Zhejiang University Hangzhou 310027 China Department of Electronic Information and Electrical Engineering Fujian University of Technology Fuzhou 350014 China

Determination of relative three-dimensional （3D） position, orientation, and relative motion between two reference frames is an important problem in robotic guidance, manipulation, and assembly as well as in other fields such as photogrammetry. A solution to pose and motion estimation problem that uses two-dimensional （2D） intensity images from a single camera is desirable for real-time applications. The difficulty in performing this measurement is that the process of projecting 3D object features to 2D images is a nonlinear transformation. In this paper, the 3D transformation is modeled as a nonlinear stochastic system with the state estimation providing six degrees-of-freedom motion and position values, using line features in image plane as measuring inputs and dual quaternion to represent both rotation and translation in a unified notation. A filtering method called the Gaussian particle filter （GPF） based on the panicle filtering concept is presented for 3D pose and motion estimation of a moving target from monocular image sequences. The method has been implemented with simulated data, and simulation results are provided along with comparisons to the extended Kalman filter （EKF） and the unscented Kalman filter （UKF） to show the relative advantages of the GPF. Simulation results showed that GPF is a superior alternative to EKF and UKF.

关键词： Gaussian particle filter (GPF) Pose and motion estimation Line features Monocular vision Extended Kalman filter(EKF) Unscented Kalman filter (UKF) Dual quatemion

Medical imaging for pancreatic diseases:Prediction of severe acute pancreatitis complicated with acute respiratory distress syndrome

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World Journal of Gastroenterology 2022年第44期28卷 6206-6212页

作者： Ling-ji song Bo Xiao Department of Radiology Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina

In this editorial we comment on the article published in the recent issue of the World Journal of Gastroenterology[2022;28(19):2123-2136].We pay attention to how to construct a simpler and more reliable new clinical predictive model to early identify patients at high risk of acute respiratory distress syndrome(ARDS)associated with severe acute pancreatitis(SAP),and to early predict the severity of organ failure from chest computed tomography(CT)findings in SAP *** we all know,SAP has a sudden onset,is a rapidly changing condition,and can be complicated with ARDS and even multiple organ dysfunction syndrome,and its mortality rate has remained *** present,there are many clinical scoring systems for AP,including the bedside index for severity in AP,acute physiology and chronic health evaluation II,systemic inflammatory response syndrome,Japanese severe score,quick sepsis-related organ failure assessment,***,some of these scoring systems are complex and require multiple and difficult clinical parameters for risk *** the aforementioned biomarkers are readily available,their ability to predict ARDS ***,it is extremely necessary to establish a simple and valuable novel model to predict the development of ARDS in *** addition,the extra-pancreatic manifestations of AP patients often involve the chest,among which pleural effusion and pulmonary consolidation are the more common ***,by measuring the semi-quantitative indexes of chest CT in AP patients,such as the amount of pleural effusion and the number of lobes involved as pulmonary consolidation,it has important reference value for the early diagnosis of SAP complicated with ARDS and is expected to provide a basis for the early treatment of ARDS.

关键词： Severe acute pancreatitis Acute respiratory distress syndrome Clinical scoring system Prediction model Semi-quantitative

Next-generation sequencing technology for the diagnosis of Pneumocystis pneumonia in an immunocompetent female:A case report

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World Journal of Clinical Cases 2023年第18期11卷 4425-4432页

作者： jing-ji Huang song-song Zhang Man-Li Liu En-Yu Yang Yu Pan jing wu The Second Clinical Medical College Guizhou University of Traditional Chinese MedicineGuiyang 550000Guizhou ProvinceChina Intensive Care Unit Guizhou Provincial People's HospitalGuiyang 550000Guizhou ProvinceChina

BACKGROUND Pneumocystis pneumonia(PCP)is a serious fungal infection usually seen in patients with human immunodeficiency virus,and it is more frequently found and has a high fatality rate in immunocompromised ***,it rarely occurs in immunocompetent ***,the clinical diagnosis of this pathogen is made more difficult by the difficulty of obtaining accurate microbiological evidence with routine *** case reports a PCP patient with normal immune function who was diagnosed through next-generation sequencing(NGS).CASE SUMMARY A 23-year-old female who had no special disease in the past was admitted to the hospital with a persistent fever and *** on the initial examination results,the patient was diagnosed with bipulmonary pneumonia,and empirical broad-spectrum antibiotic therapy was ***,due to the undetermined etiology,the patient's condition continued to *** was transferred to the intensive care unit because of acute respiratory *** the diagnosis of Pneumocystis jirovecii infection through NGS in bronchoalveolar lavage fluid and treatment with trimethoprim/sulfamethoxazole and caspofungin,the patient gradually recovered and had a good *** This case emphasizes that,for patients with normal immune function the possibility of PCP infection,although rare,cannot be *** plays an important role in the diagnosis of refractory interstitial pneumonia and acute respiratory failure.

关键词： Pneumocystis pneumonia Pneumocystis jirovecii Next-generation sequencing Immunocompetent Trimethoprim/Sulfamethoxazole Case report

6-DOF Motion Assessment of A Hydrodynamic Numerical Simulation of A Semisubmersible Platform Using Prototype Monitoring Data

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China Ocean Engineering 2022年第4期36卷 575-587页

作者： LI song wu Wen-hua YAO Wei-an Faculty of Vehicle Engineering and Mechanics Dalian University of TechnologyDalian 116024China State Key Laboratory of Structural Analysis of Industrial Equipment Dalian University of TechnologyDalian 116024China Research Institute of Dalian University of Technology in Shenzhen Gaoxin South fourth Road Nanshan DistrictShenzhen 518057China

Hydrodynamic numerical simulations are used to conduct structural analyses and inform the design of engineered marine *** this paper,a hydrodynamic numerical model of“Nanhai Tiaozhan”(NHTZ)FPS platform was established according to its design *** model was assessed with two sets of field monitoring data representing harsh and conventional sea *** motion responses of the platform according to the measured data and the hydrodynamic simulation were compared by reviewing their statistical characteristics,distributions,and spectrum *** comparison showed that the hydrodynamic model could correctly simulate the frequency domain characteristics of the motion responses of the ***,the simulation underestimated the reciprocating motions of the floating body and the influence of slow drift on the motion of the ***,analysis of the monitoring data revealed that the translational degrees of freedom(DOF)and rotational DOF of the platform were coupled,but these coupled motion states were not apparent in the hydrodynamic simulation.

关键词： prototype monitoring hydrodynamic numerical simulation statistical characteristics semisubmersible platform reciprocating motions

Direct detection of a single[4Fe-4S]cluster in a tungsten-containing enzyme:Electrochemical conversion of CO_(2) into formate by formate dehydrogenase

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Carbon Energy 2023年第5期5卷 152-164页

作者： Wenjin Li Yanxin Gao Xuan Sun Lei Wan Haishuo ji Hang Luo Yao Tian Hao song Geng wu Liyun Zhang State Key Laboratory of Medicinal Chemical Biology College of Life ScienceNankai UniversityTianjinPeople's Republic of China State Key Laboratory of Microbial Metabolism The Joint International Research Laboratory of Metabolic&Developmental SciencesSchool of Life Science and BiotechnologyShanghai Jiao Tong UniversityShanghaiPeople's Republic of China Max Planck Institute for Chemical Energy Conversion Mülheim an der RuhrGermany Frontier Science Center for Synthetic Biology Key Laboratory of Systems BioengineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjinPeople's Republic of China

The conversion of CO_(2) into fuels and valuable chemicals is one of the central topics to combat climate change and meet the growing demand for renewable ***,we show that the formate dehydrogenase from Clostridium ljungdahlii(ClFDH)adsorbed on electrodes displays clear characteristic voltammetric signals that can be assigned to the reduction and oxidation potential of the[4Fe-4S]^(2+/+)cluster under nonturnover *** adding substrates,the signals transform into a specific redox center that engages in catalytic electron *** catalyzes rapid and efficient reversible interconversion between CO_(2) and formate in the presence of *** turnover frequency of electrochemical CO_(2) reduction is determined as 1210 s^(-1) at 25℃ and pH 7.0,which can be further enhanced up to 1786 s^(-1) at 50℃.The Faradaic efficiency at−0.6 V(*** hydrogen electrode)is recorded as 99.3%in a 2-h *** experiments and theoretical modeling disclose interesting pathways for CO_(2) entry,formate exit,and OCN−competition,suggesting an oxidation-state-dependent binding mechanism of *** results provide a different perspective for understanding the catalytic mechanism of FDH and original insights into the design of synthetic catalysts.

关键词： bioelectrocatalysis biofuel CO_(2)conversion formate dehydrogenase iron-sulfur cluster