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Condition-Based Spare Ordering Model for a Two-Stage Degrading System

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Journal of Systems Science and Systems Engineering 2020年第1期29卷 85-99页

作者： cheng Wang Jianxin Xu Zhenming Zhang Hongjun Wang School of Mechanical Engineering Xi'an Aeronautical UniversityXi'an 710077China School of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072China Key Laboratory of Modern Measurement and Control Technology Ministry of EducationBeijing Information Science and Technology UniversityBeijing 100192China

Proper supply of spares is critical to guarantee safe operation,improve service quality and reduce maintenance *** paper proposes a condition-based spare ordering model for a two-stage degrading system,which consists of inflection point transfer process and two-stage degradation process with continuous degradation process and random external *** shocks itself does not directly lead to system failure,but it will speed up the degradation *** turn,degradation can also make the system more vulnerable to *** general,the degradation rate at the defective stage is greater than that at the normal *** proposed model depends on system degradation process and spare *** order to achieve accurate maintenance and deal with emergency maintenance caused by system rapid degradation after inflection point transfer time,the model considers both the regular lead-time and expedited *** inflection point transfer time,regular spare ordering policy is *** inflection point transfer time,expedited spare ordering policy is *** decision variable of the model is the ordering *** objective of this study is to determine the optimal ordering time such that the expected cost rate is ***,a numerical example is presented to illustrate the proposed model and sensitivity analysis on critical parameters is carried out.

关键词： Condition-based spare ordering inflection point two-stage degradation random external shocks random lead-time

Barrier Lyapunov Function-Based Finite-Time Dynamic Surface Control for Output-Constrained Nonstrict-Feedback Systems

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Journal of Systems Science & Complexity 2023年第2期36卷 524-539页

作者： YU Jinpeng FU cheng LIU Jiapeng MA Yumei The College of Automation Qingdao UniversityQingdao 266003China Shandong Key Laboratory of Industrial Control Technology Qingdao UniversityQingdao 266003China The School of Control Science and Engineering Shandong UniversityJinan 250100China

This paper investigates a finite-time tracking problem for the uncertainty nonlinear systems in nonstrict-feedback form,in which the output signal is restricted in a *** on the barrier Lyapunov function and dynamic surface control scheme,a novel adaptive neural controller is proposed by using the finite-time Lyapunov *** the aforementioned literature on finite time tracking control,the violation of system output constraint is avoided by combining the barrier Lyapunov function method with finite-time *** structural characteristics of neural network is introduced to expand the adaptive neural finite-time backstepping method to the uncertainty nonlinear systems in the non-strict ***,the dynamic surface control is introduced to cope with the problem of“explosion of complexity”inherent in conventional backstepping *** is shown that the designed controller can achieve finite-time tracking control and all the variables in the closed-loop system are bounded with output constraint guaranteed form stability analysis and simulation results.

关键词： Adaptive neural network control explosion of complexity finite-time tracking nonstrictfeedback form

Small ubiquitin-like modifier protein-specific protease 1 and prostate cancer

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Asian Journal of Andrology 2009年第1期11卷 36-38页

作者： Yong Zuo Jin-Ke cheng Laboratory for Cell Signal Transduction Institute of Medical Sciences Shanghai Jiao Tong University School ofMedicine Shanghai 200025 China

Small ubiquitin-like modifier protein （SUMO） modification is a highly dynamic process, catalyzed by SUMO- specific activating （El）, conjugating （E2） and ligating （E3） enzymes, and reversed by a family of SUMO-specific proteases （SENPs）. There are six members of the human SENP family, and each SENP has different cellular locations and substrate specificities. However, the precise roles of SENPs in cellular processes have not been elucidated to date. This brief review will focus on recent advances pertaining to the identified targets of SENP 1 and its potential role in prostate cancer.

关键词： SUMO SUMO-specific protease prostate cancer androgen receptor HIF 1α

ST-Trader:A Spatial-Temporal Deep Neural Network for Modeling Stock Market Movement

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IEEE/CAA Journal of Automatica Sinica 2021年第5期8卷 1015-1024页

作者： Xiurui Hou Kai Wang cheng Zhong Zhi Wei the Department of Computer Science New Jersey Institute of TechnologyNewarkNJ 07102 USA the School of Business Stevens Institute of TechnologyHobokenNJ 07030 USA

Stocks that are fundamentally connected with each other tend to move *** such common trends is believed to benefit stock movement forecasting ***,such signals are not trivial to model because the connections among stocks are not physically presented and need to be estimated from volatile *** by this observation,we propose a framework that incorporates the inter-connection of firms to forecast stock *** effectively utilize a large set of fundamental features,we further design a novel ***,we use variational autoencoder(VAE)to reduce the dimension of stock fundamental information and then cluster stocks into a graph structure(fundamentally clustering).Second,a hybrid model of graph convolutional network and long-short term memory network(GCN-LSTM)with an adjacency graph matrix(learnt from VAE)is proposed for graph-structured stock market *** on minute-level *** market data demonstrate that our model effectively captures both spatial and temporal signals and achieves superior improvement over baseline *** proposed model is promising for other applications in which there is a possible but hidden spatial dependency to improve time-series prediction.

关键词： Graph convolution network long-short term memory network stock market forecasting variational autoencoder(VAE)

Predicting surgical site infections using a novel nomogram in patients with hepatocelluar carcinoma undergoing hepatectomy

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World Journal of Clinical Cases 2019年第16期7卷 2176-2188页

作者： Tian-Yu Tang Yi Zong Yi-Nan Shen cheng-Xiang Guo Xiao-Zhen Zhang Xiu-wen Zou Wei-Yun Yao Ting-Bo Liang Xue-Li Bai Department of Hepatobiliary and Pancreatic Surgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina The 5^th Department of Hepatic Surgery Eastern Hepatobiliary Surgery Hospitalthe Second Military Medical UniversityShanghai 20000China Department of Surgery Changxing People’s HospitalHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Surgical site infections (SSI) remain a major cause of morbidity after hepatectomy for hepatocellular carcinoma (HCC).AIM To identify the risk factors associated with SSI,and develop a nomogram to predict SSI among patients undergoing *** We retrospectively reviewed the data of patients diagnosed with HCC undergoing hepatectomy at two academic institutions in China,and evaluated the occurrence of *** risk factors for SSI were identified using univariate and multivariate *** on these independent risk factors,a nomogram was established using the data of patients in the first institution,and was validated using data from an external independent cohort from the second *** The nomogram was established using data from 309 patients,whereas the validation cohort used data from 331 *** operation duration,serum albumin level,repeat hepatectomy,and ASA score were identified as independent risk *** concordance index (C-index) of the nomogram for SSI prediction in the training cohort was 0.86;this nomogram also performed well in the external validation cohort,with a C-index of ***,we stratified patients into three groups,with a distinct risk range based on the nomogram prediction,to guide clinical *** Our novel nomogram offers good preoperative prediction for SSIs in patients undergoing hepatectomy.

关键词： Surgical site infection Nomogram Hepatectomy Risk factors

Preparation of a novel chelating resin for the removal of Ni^(2+)from water

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Chinese Chemical Letters 2014年第2期25卷 265-268页

作者： Yuan-Hui Peng Jin-Nan Wang Xin Yang cheng cheng Thomas Wintgens State Key Laboratory of Pollution Control and Resource Reuse ε School of the Environment University of Applied Sciences Northwestern Switzerland(FHNW)

A new chelating resin DVB-MA-HDA modified with hydroxamic acid groups was prepared for the fast removal of Ni2＋ from water. SEM, BET, elemental analysis, FT-IR spectroscopy and XPS were used to characterize this new adsorbent. Batch adsorption experiment indicated that the equilibrium adsorption capacity of DVB-MA-HD for Ni2＋ was more than 130mg/g, and the adsorption isotherm can be well fitted by the Langmuir model. The adsorption kinetic curve indicates that more than 60% of the adsorption amount of Ni2＋ at equilibrium occurred within the initial 20 rain. 0.1 mol/L EDTA solution could desorb Ni2＋ from DVB-MA-HDA effectively.

关键词： jChelating resin Adsorption Ni2+

Experiments on Channel Evolution Caused by Check-dam Failure

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Journal of Mountain Science 2012年第2期9卷 175-184页

作者： wen-Hsiao TSENG Hsiao-wen WANG Shih-Chieh CHOU Yu-Lin KAO Chjeng-Lun Shieh Department of Hydraulic and Ocean Engineering National Cheng Kung University

A 10 m long,0.2 m wide flume was employed to simulate the channel bed evolution of check-dam *** experiment longitudinal profiles,the gradient of channel bed,head-cutting propagation distance and deposition length were compared with the theoretical solution derived from a sediment transport diffusion *** contrast with the theoretical solution,two different gradients were obtained upstream and downstream of the *** theoretical solution provides a good description of the changes upstream of the check-dam. The ratio of clear water depth to sediment moving layer thickness in the experiment was analyzed and showed that high concentration sediment laden flow was taken in the incipient of check-dam failure,which may be the reason why the experiment result was slightly different from the theoretical solution in the downstream of check-dam.

关键词： Check-dam failure Diffusion equation Debris flow

A revisit to the role of Mo in an MP35N superalloy:An experimental and theoretical study

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Journal of Materials Science & Technology 2023年第26期157卷 60-70页

作者： Qing cheng Jinyong Mo Xiaoqing Li Xiandong Xu Center for High Resolution Electron Microscopy College of Materials Science and EngineeringHunan UniversityChangsha 410082China Institute of Massive Amorphous Metal Science School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China Department of Materials Science and Engineering Applied Materials Physics KTH-Royal Institute of TechnologyStockholm SE-10044Sweden

Molybdenum(Mo)has been recognized as an essential alloying element of the MP35N(Co_(35.4)Cr_(22.9)Ni_(35.5)Mo_(6.2),at.%)superalloy for enhancing strength and corrosion ***,a full understanding of the addition of Mo on microstructure and mechanical properties of the Mo-free parent alloy is *** this work,we consider five(Co_(37.7)Cr_(24.4)Ni_(37.9))_(100-x)Mo_(x)(x=0,0.7,2.0,3.2,and 6.2)alloys,and reveal that yield/tensile strength and ductility are continuously increased for these alloys with increasing Mo content while a single-phase face-centered cubic structure remains *** is found that strong solid solution strengthening(SSS)is a main domain to the improved yield strength,whereas grain boundaries are found to soften by the Mo *** first-principles calculations demonstrate that a severe local lattice distortion contributes to the enhanced SSS,and the grain boundary softening effect is mostly associated with the decreased shear *** first-principles calculations and scanning transmission electron microscopy observations reveal that the stacking fault energy(SFE)reduces by the Mo *** calculated SFE value decreases from 0.4 mJ/m^(2) to-11.8 mJ/m^(2) at 0 K as Mo content increases from 0 at.%to 6.2 at.%,and experimentally measured values of SFE at room temperature for both samples are about 18 mJ/m^(2) and 9 mJ/m^(2),*** reduction of SFE promoted the generation of stacking faults and deformation twins,which sustain a high strain hardening rate,thus postponing necking instability and enhancing tensile strength and elongation.

关键词： Mo addition Solid solution strengthening Grain boundary softening Local lattice distortion First-principles simulations Stacking fault energy Deformation twin

Novel Selenium-containing Human Single-chain Variable Fragment with Glutathione Peroxidase Activity from Computer-aided Molecular Design

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Chemical Research in Chinese Universities 2011年第5期27卷 813-819页

作者： WANG cheng WAN Pei GONG Ping-sheng LV Li-min XU Ya-wei ZHAO Yang HE Bo ZHAO Gang YAN Gang-lin MU ying LV Shao-wu LUO Gui-min Key Laboratory for Molecular Enzymology and Engineering Ministry of Education College of Life Science Jilin University Changchun 130012 P. R. China State Key Laboratory of Industrial Control Technology Research Center for Analytical Instrumentation Institute of Cyber-systems and Control Zhejiang University Hangzhou 310058 P. R. China Department of Biochemistry School of Basic Medical Sciences Jilin Medical College Jilin 132013 P. R. China

In order to enhance the glutathione peroxidase（GPX） catalytic activity of the selenium-containing single-chain variable fragments（Se-scFv）, a novel human scFv was designed on the basis of the structure of human antibody and optimized via bioinformatics methods such as homologous sequence analysis, three-dimensional（3D） model building, binding-site analysis and docking. The DNA sequence of the new human scFv was synthesized and cloned into the expression vector pET22b（＋）, then the scFv protein was expressed in soluble form in Escherichia coli BL21（DE3） and purified by Ni2＋-immobilized metal affinity chromatography（IMAC）. The serine residue of scFv in the active site was converted into selenocysteine（Sec） with the chemical modification method, thus, the human Se-scFv with GPX activity was obtained. The GPX activity of the Se-scFv protein was characterized. Compared with other Se-scFv, the new human Se-scFv showed similar efficiency for catalyzing the reduction of hydrogen peroxide by glutathione. It exhibited pH and temperature dependent catalytic activity and a typical ping-pong kinetic mechanism.

关键词： Glutathione peroxidase(GPX) Single-chain variable fragment(scFV) Three-dimensional model Selenium