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A Novel Product Remaining Useful Life Prediction Approach Considering Fault Effects

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IEEE/CAA Journal of Automatica Sinica 2021年第11期8卷 1762-1773页

作者： Jingdong lin zheng lin Guobo Liao Hongpeng Yin School of Automation Chongqing UniversityChongqing 400044China

In this paper,a novel remaining useful life prediction approach considering fault effects is *** Wiener process is used to construct the degradation process of single performance characteristic with the fault *** first passage time based remaining useful life distribution is calculated by assuming fault occurrence moment is a random variable and follows a certain *** maximization algorithm is employed to estimate model parameters,where the fault occurrence moment is considered as a missing ***,a Copula function is used to describe the dependence between the multiple performance characteristics and derive joint remaining useful life(RUL)distribution of product with the fault *** effectiveness of the proposed approach is verified by the experiments of turbofan engines.

关键词： Degradation process fault effects fault occurrence moment(FOM) performance characteristic(PC) remaining useful life(RUL)

Macroblock-level decoding and deblocking method and its pipeline implementation in H.264 decoder SOC design

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 36-41页

作者： WANG Shu-hui lin Tao lin zheng-hui Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200030 China

This paper presents a macroblock-level (MB-level) decoding and deblocking method for supporting the flexible macroblock ordering (FMO) and arbitrary slice ordering (ASO) bit streams in H.264 decoder and its SOC/ASIC implementation. By searching the slice containing the current macroblock in the bit stream and switching slices correctly, MBs can be decoded in the raster scan order, while the decoding process can immediately begin as long as the slice containing the current MB is available. This architectural modification enables the MB-level decoding and deblocking 3-stage pipeline, and saves about 20% of SDRAM bandwidth. Implementation results showed that the design achieves real-time decoding of 1080HD (1920×1088@30 fps) at a system clock of 166 MHz.

关键词： Flexible macroblock ordering (FMO) Arbitrary slice ordering (ASO) System-on-chip (SOC) Raster scan order Pipeline

THE GLOBAL EXISTENCE AND UNIQUENESS OF SMOOTH SOLUTIONS TO A FLUID-PARTICLE INTERACTION MODEL IN THE FLOWING REGIME

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Acta Mathematica Scientia 2024年第5期44卷 1877-1885页

作者： lin zheng Shu WANG College of Mathematics and Statistics North China University of Water Resources and Electric PowerZhengzhou450046China School of Mathematics Statistics and MechanicsBeijing University of TechnologyBeijing100124China

This paper is concerned with the Cauchy problem for a 3D fluid-particle interaction model in the so-called flowing regime inℝ*** the smallness assumption on both the external potential and the initial perturbation of the stationary solution in some Sobolev spaces,the existence and uniqueness of global smooth solutions in H3 of the system are established by using the careful energy method.

关键词： fluid-particle flowing regime global existence

Co-strengthening contribution of δ′and T_1 precipitates in Al-Li alloys 2090 and 2090+Ce

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Rare Metals 2006年第3期25卷 197-201页

作者： ZHAO Zhilong LIU lin CHEN zheng School of Mechatronic Engineering Northwestern Polytechnic University Xi＇an 710072 China

The microstructure of dislocation in two kinds of ahiminum-lithium alloys 2090 and 2090 ＋ Ce was observed by means of TEM technology. The contributions of δ＇ and T1 precipitates to strength were separately calculated by using the results of quantitative metallography and analysis of micro-deformation behavior; the co-strengthening effect of δ＇ and T1 precipitates was studied. The results show that the adding relationship of co-strengthening of δ＇ and T1 is in accordance with q = 1.4 form at the near peak-aged condition, i.e., △τ^1.4δ = △τ^1.4δ＋ △τ^1.4T1, but the adding relationship is approximately a linear relation （q = 1） at the under-aged condition and becomes the parabola form when over-aged （q = 2）. The adding relationship of co-strengthening contribution of δ＇ and T1 is obviously dependent on aging time.

关键词： metal materials aluminum-lithium alloy precipitates strengthening

Marine renewable energy in China: Current status and perspectives

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Water Science and Engineering 2014年第3期7卷 288-305页

作者： Yong-liang ZHANG zheng lin Qiu-lin LIU State Key Laboratory of Hydro-Science and Engineering Tsinghua University

Based on a general review of marine renewable energy in China, an assessment of the development status and amount of various marine renewable energy resources, including tidal energy, tidal current energy, wave energy, ocean thermal energy, and salinity gradient energy in China＇s coastal seas, such as the Bohai Sea, the Yellow Sea, the East China Sea, and the South China Sea, is presented. We have found that these kinds of marine renewable energy resources will play an important role in meeting China＇s future energy needs. Additionally, considering the uneven distribution of China＇s marine renewable energy and the influences of its exploitation on the environment, we have suggested several sites with great potential for each kind of marine energy. Furthermore, perspectives on and challenges related with marine renewable energy in China are addressed.

关键词： renewable energy tidal energy tidal current energy wave energy ocean thermalenergy salinity gradient energy

Mechanism study of Cu(Ⅱ) adsorption from acidic wastewater by ultrasonic-modified municipal solid waste incineration fly ash

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Chinese Journal of Chemical Engineering 2024年第3期67卷 157-165页

作者： Shunda lin Yang Lu lin zheng ling Long Xuguang Jiang Jianhua Yan State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China Zhejiang University Qingshanhu Energy Research Center Hangzhou 310027China Hangzhou Xiaoshan Jinjiang Green Energy Co. Ltd.XiaoshanHangzhou 310000China

High concentrations of copper ions(Cu(Ⅱ)) in water will pose health risks to humans and the ecological environment. Therefore, this study aims to utilize ultrasonic-cured modified municipal solid waste incineration(MSWI) fly ash for Cu(Ⅱ) adsorption to achieve the purpose of “treating waste by waste.” The effects of p H, adsorption time, initial concentration, and temperature on the modified MSWI fly ash’s adsorption efficiency were systematically studied in this article. The adsorption performance of the modified MSWI fly ash can be enhanced by the ultrasonic modification. At pH = 2, 3 and 4, the adsorption capacity of the modified MSWI fly ash for Cu(Ⅱ) increased by 2.7, 1.9 and 1.2 times, respectively. Furthermore, it was suggested that the adsorption process of the modified MSWI fly ash can be better simulated by the pseudo-second-order kinetic model, with a maximum adsorption capacity calculated by the Langmuir model of 24.196 mg.g-1. Additionally, the adsorption process is spontaneous,endothermic, and chemisorption-dominated from the thermodynamic studies(ΔH and ΔS > 0, ΔG < 0).Finally, the enhanced adsorption performance of the modified MSWI fly ash for Cu(Ⅱ) may be attributed to electrostatic interaction and chelation effects.

关键词： Ultrasound MSWI fly ash Cu(Ⅱ) Wastewater Adsorption

MIMO-FSK non-coherent detection with spatial multiplexing in fast-fading environment

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The Journal of China Universities of Posts and Telecommunications 2020年第5期27卷 47-54页

作者： zheng lin Wang Zhen Chen Jianmei lin Mengying Deng Xiaofang Guangxi Key Lalxiralory of Wireless Wideband Communications and Signal Processing Guilin University of Electronic TechnologyGuilin 541004China Science and Technology on Communication Networks Laboratory Shijiazhuang 050081China

Accurate estimationand real-time compensation for phase offset and Doppler shift are essential for coherent multi-input multi-output(MIMO)***,a spatial multiplexing MIMO scheme with non-coherent frequency-shift keying(FSK)detection is *** is immune to random phase interference and Doppler shift while increasing *** is valuable that the proposed spatial multiplexing MIMO based on energy detection(ED)is equivalent to a linear system,and there is no mutual interference caused by the product of simultaneous signals in square-law *** equivalent MIMO channel model is derived as a real matrix,which remains maximal multiplexing capacity and reduces the channel estimation *** results show that the proposed scheme has outstanding performance over Rician flat fading channel,and experimental system obtains four times the capacity through 4 antennas on both transmitter and receiver.

关键词： non-coherent MIMO MIMO-FSK spatial multiplexing experimental system

Dual-sided symmetric crystalline orientation of covalent organic framework membranes for unidirectional anhydrous proton conduction

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Science China Chemistry 2022年第12期65卷 2548-2557页

作者： Shujing Liu zheng lin Changchun Wang Jia Guo State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science and Lab of Advanced MaterialsFudan UniversityShanghai200438China

Two-dimensional covalent organic frameworks(2D COFs)have sparkled wide-ranging research to explore proton-conducting ***,the powder-pressed pellets or continuous membranes of 2D COFs are composed of randomly arranged crystallites,which are undesirable for proton transport via a shortcut *** report a controlled strategy for preparing a conformably oriented free-standing COF membrane to address the critical challenge.A monofunctional aldehyde precursor is used as a modulator to enhance reversible association and optimize growth orientation in an interfacial polymerization *** preferred face-on alignment is achieved throughout the membrane from its flat side to the nanoflake-standing side and,in turn,generates the unidirectional pore channels for accommodating 1,2,4-triazole as proton *** composite merges distinctive features including orientation,crystallinity,porosity,and mechanical strength into one system,exhibiting ultrafast and stable anhydrous proton conduction at high operating temperatures with low activation *** findings offer an innovative strategy for the oriented crystallization of free-standing COF membranes for energy conversion applications.

关键词： covalent organic frameworks oriented crystallization anhydrous proton conduction interfacial polymerization membranes

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DEM Modeling of Particle Breakage in Silica Sands under One-Dimensional Compression

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Acta Mechanica Solida Sinica 2016年第1期29卷 78-94页

作者： Danda Shi lin zheng Jianfeng Xue Jing Sun School of Ocean Science and Engineering Shanghai Maritime University School of Engineering and Information Technology Federation University Australia

A Discrete Element Method （DEM） model is developed to study the particle break- age effect on the one-dimensional compression behavior of silica sands. The ＇maximum tensile stress＇ breakage criterion considering multiple contacts is adopted to simulate the crushing of circular particles in the DEM. The model is compared with published experimental results. Com- parison between the compression curves obtained from the numerical and experimental results shows that the proposed method is very effective in studying the compression behavior of silica sands considering particle breakage. The evolution of compression curves at different stress levels is extensively studied using contact force distribution, variation of contact number and particle size distribution curve with loading. It is found that particle breakage has great impact on com- pression behavior of sand, particularly after the yield stress is reached and particle breakage starts. The crushing probability of particles is found to be macroscopically affected by stress level and particle size distribution curve, and microscopically related to the evolutions of contact force and coordination number. Once the soil becomes well-graded and the average coordination number is greater than 4 in two-dimension, the crushing probability of parent particles can reduce by up to 5/6. It is found that the average contact force does not always increase with loading, but increases to a peak value then decreases once the soil becomes more well-graded. It is found through the loading rate sensitivity analysis that the compression behavior of sand samples in the DEM is also affected by the loading rate. Higher yield stresses are obtained at higher loading rates.

关键词： particle breakage silica sand particle breakage criterion one-dimensional com-pression Discrete Element Method (DEM)