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Specific Energy Consumption Analysis Model and Its Application in Typical Steel Manufacturing Process

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Journal of Iron and Steel Research International 2010年第10期17卷 33-37页

作者： SUN Wen-qiang CAI Jiu-ju DU Tao zhang Da-wei The State Environmental Protection Agency Key Laboratory on Eco-Industry Northeastern UniversityShenyang 110819 Liaoning China

Theoretical minimum and actual specific energy consumptions （SEC） of typical manufacturing process （SMP） were studied. Firstly, a process division of a typical SMP in question was conducted with the theory of SEC analysis. Secondly, an exergy analysis model of a subsystem consisting of several parallel processes and a SEC analysis model of SMP were developed. And finally, based on the analysis models, the SEC of SMP was analyzed by means of the statistical significance. The results show that the SEC of typical SMP comprises the theoretical minimum SEC and the additional SEC derived from the irreversibility~ and the SMP has a theoretical minimum SEC of 6.74 GJ/t and an additional SEC of 19.32 GJ/t, which account for 25.88% and 74.12% of the actual SEC, respectively.

关键词： steel manufacturing process theoretical minimum specific energy consumption additional specific energy consumption actual specific energy consumption specific energy consumption analysis exergy analysis

Surface Modification for WSe2 Based Complementary Electronics

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Chinese Physics Letters 2020年第11期37卷 110-113页

作者： Ming-liang zhang Xu-Ming Zou Xing-qiang liu Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China

High-performance WSe2 complementary transistors are demonstrated on an individual flake by ozone exposure,which relies on the charge transfer *** technology is readily feasible for modulating the conductivity type in WSe2,and the p–n junction presents a high on-off ratio of *** on robust p-type transistors and matched output current of n-type WSe2 transistors,the complementary inverter achieves a high voltage gain of ***,this strategy may provide an avenue for development of high-performance complementary electronics.

关键词： complementary inverter matched

A study on performance influences of airfoil aerodynamic parameters and evaluation indicators for the roughness sensitivity on wind turbine blade

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Science China(Technological Sciences) 2011年第11期54卷 2993-2998页

作者： HUANG ChenWu YANG Ke liU qiang zhang Lei BAI JingYan XU JianZhong Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The roughness increase on horizontal axis wind turbine(HAWT) blade surface,especially on the leading edge,can lead to an aerodynamic performance degradation of blade and power output loss of HAWT,so roughness sensitivity is an important factor for the HAWT blade ***,there is no criterion for evaluating roughness sensitivity of blade *** this paper,the performance influences of airfoil aerodynamic parameters were analyzed by the blade element momentum(BEM) method and 1.5 MW wind turbine *** showed that airfoil lift coefficient was the key parameter to the power output and axial thrust of ***,the evaluation indicators of roughness sensitivity for the different spanwise airfoils of the pitch-regulated HAWT blade were *** respectively were the lift-to-drag ratio and lift coefficient without feedback system,the maximum lift-to-drag ratio and design lift coefficient with feedback system for the airfoils at outboard section of blade,and lift coefficient without feedback,maximum lift coefficient with feedback for the airfoils at other sections under the pitch-fixed and variable-speed *** is not necessary to consider the roughness when HWAT can be regulated to the rated power output by the pitch-regulated and invariable-speed operation.

关键词： HAWT blade airfoil aerodynamic performance roughness sensitivity evaluation indicator

Time-varying sliding mode control of missile based on suboptimal method

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Journal of Systems Engineering and Electronics 2021年第3期32卷 700-710页

作者： li Zongxing zhang Rui Beijing Institute of Electronic System Engineering Beijing 100854China

This paper proposes a time-varying sliding mode control method to address nonlinear missile body kinematics based on the suboptimal control *** analytical solution of suboptimal time-varying sliding surface and the corresponding suboptimal control law are obtained by solving the state-dependent Riccati equation ***,the Lyapunov method is used to analyze the motion trend in sliding surface and the asymptotic stability of the closed-loop system is *** suboptimal control law is transformed to the form of pseudo-angle-of-attack *** simulation results indicate that the satisfactory performance can be obtained and the control law can overcome the influence of parameter errors.

关键词： suboptimal control Riccati equation analytic solution sliding mode control nonlinear control

Remote Data Auditing for Cloud-Assisted WBANs with Pay-as-You-Go Business Model

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Chinese Journal of Electronics 2023年第2期32卷 248-261页

作者： li Yumei zhang Futai School of Computer Science Hubei University of Technology Fujian Provincial Key Laboratory of Network Security and Cryptology College of Computer and Cyber SecurityFujian Normal University

As an emerging technology, cloud-assisted wireless body area networks(WBANs) provide more convenient services to users. Recently, many remote data auditing protocols have been proposed to ensure the data integrity and authenticity when data owners outsourced their data to the cloud. However, most of them cannot check data integrity periodically according to the pay-as-you-go business model. These protocols also need high tag generation computation overhead, which brings a heavy burden for data owners. Therefore, we construct a lightweight remote data auditing protocol to overcome all above drawbacks. Our work can be deployed in the public environment without secret *** makes use of certificate-based cryptography which gets rid of certificate management problems, key escrow problems, and secret channels. The security analysis illustrates that the proposed protocol is secure. Moreover, the performance evaluation implies that our work is available in cutting down computation and communication overheads.

关键词： Wireless communication Performance evaluation Protocols Computational modeling Data integrity Data models Computational efficiency

A High Order Accurate Bound-Preserving Compact Finite Difference Scheme for Two-Dimensional Incompressible Flow

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Communications on Applied Mathematics and Computation 2024年第1期6卷 113-141页

作者： Hao li Xiangxiong zhang Department of Mathematics Purdue University150 N.University StreetWest LafayetteIN47907-2067USA

For solving two-dimensional incompressible flow in the vorticity form by the fourth-order compact finite difference scheme and explicit strong stability preserving temporal discretizations,we show that the simple bound-preserving limiter in li et al.(SIAM J Numer Anal 56:3308–3345,2018)can enforce the strict bounds of the vorticity,if the velocity field satisfies a discrete divergence free *** reducing oscillations,a modified TVB limiter adapted from Cockburn and Shu(SIAM J Numer Anal 31:607–627,1994)is constructed without affecting the bound-preserving *** bound-preserving finite difference method can be used for any passive convection equation with a divergence free velocity field.

关键词： Finite difference Monotonicity Bound-preserving Discrete maximum principle Passive convection Incompressible flow Total variation bounded limiter

Coseismic surface deformation of the 2014 Napa earthquake mapped by Sentinel-1A SAR and accuracy assessment with COSMO-SkyMed and GPS data as cross validation

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International Journal of Digital Earth 2017年第12期10卷 1197-1213页

作者： Yinghui Yang qiang Chen Qian Xu Yijun zhang Qi Yong Guoxiang liu School of Civil Engineering and Architecture Southwest Petroleum UniversityChengduPeople’s Republic of China Department of Remote Sensing and Geoinformation Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China

The new land observation satellite Sentinel-1A was launched on 25 April 2014 with a C-band synthetic aperture radar(SAR)sensor,which has the significant enhancements in terms of revisit period and high *** Mw 6.1 Napa,California earthquake occurring on 24 August 2014,almost 4 months after the launch,is the first moderate earthquake imaged by the *** provides an opportunity to map the coseismic deformation of the event and evaluate the potential of Sentinel-1A SAR for earthquake *** techniques including the interferometric SAR(InSAR)and pixel offset-tracking(PO)are,respectively,employed to map the surface deformation along the radar line of sight(LOS),azimuth and slant-range *** cross comparison between Sentinel-1A InSAR LOS deformation and GPS observations indicates good agreement with an accuracy of∼2.6 *** further estimate the earthquake source model with the external COSMO-SkyMed InSAR and GPS data as constraints,and forward calculate the surface deformation as cross validation with the Sentinel-1A *** comparison between the observed and modeled deformation shows that the Sentinel-1A measurement accuracy can achieve 1.6 cm for InSAR technique along LOS direction,and 6.3 and 6.7 cm for PO along azimuth and range directions,respectively.

关键词： Sentinel-1A SAR Napa earthquake COSMO-SkyMed InSAR source model accuracy assessment

Bacterial spectrum and resistance patterns in corneal infections at a Tertiary Eye Care Center in South China

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International Journal of Ophthalmology(English edition) 2016年第3期9卷 384-389页

作者： Nan Wang qiang Huang Yi-Wei Tan li-Ping lin Kai-li Wu Zhongshan Ophthalmic Center State Key Laboratory of OphthalmologySun Yat-sen University

AIM： To investigate the spectrum and antibiotic susceptibility of bacteria isolated from patients with suspected corneal infections in Zhongshan Ophthalmic Center in South China over the past four years retrospectively. METHODS： Totally 1943 corneal scrapes from patients with corneal infections from 2010 to 2013 were cultured and processed using standard microbiological procedures to identify bacterial isolates. Simultaneously, the bacterial isolates were tested for antibiotic susceptibility to 8 antibiotics （ceftazidime, cefuroxim, cefazolin, levofloxacin, ofloxacin, neomycin, tobramycin, chloramphenicol） using the Kirby-Bauer disc diffusion technique. RESULTS： Of the total 1943 scrapes, 397 （20.43%） were culture-positive, of which 294 （74.06%） were gram- positive （GP） and 103 （25.94%） were gram-negative （GN） bacteria. Of the GP organisms, the most prevalent genera were Staphylococcus spp. （56.17%, n=223）, Kocuria spp. （5.29%, n=21） and Micrococcus spp. （1.26%, n=5）. On the other hand, the most prevalent genera were Pseudomonas spp. （12.85%, n=51）, Burkholderia spp. （2.02%, n=8） and Acinetobacter spp. （1.51%, n =6） for the GN organisms. Among five antibiotics that have eye drop products, the resistant to neomycin of GP （7.82%, 95% Ch 4.72%-10.92%） and GN isolates （9.71%, 95% Ch 4.01%-15.41% ） was lowest, while the resistant to chloramphenicol was highest （GP： 34.35%, 95% Ch 28.92%-39.78%; GN： 60.19%, 95% Ch 50.74%-69.64%）. CONCLUSION： Staphylococcus spp. was the most common bacterial pathogens isolated from patients with corneal infections in this setting. High percentages of GP and GN bacteria were mostly susceptible to neomycin and highly resistant to chloramphenicol.

关键词： antibiotic susceptibility epidemiology corneal infections bacterial spectrum

Dynamic Performance Evaluation of a Redundantly Actuated and Over-constrained Parallel Manipulator

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International Journal of Automation and computing 2019年第3期16卷 274-285页

作者： Hai-qiang zhang Hai-Rong Fang Bing-Shan Jiang Shuai-Guo Wang School of Mechanical.Electronic and Control Engineering Beijing Jiaotong UniversityBeijing 100044China MH Robot&Automation limited Company Wei fang 262200China

This paper presents a redundantly actuated and over-constrained 2 RPU-2 SPR parallel manipulator with two rotational and one translational coupling degrees of *** kinematics analysis is firstly carried out and the mapping relationship of the velocity,acceleration and the independent parameters between the actuator joint and the moving platform are deduced by using the vector dot product and cross product *** employing d′Alembert′s principle and the principle of virtual work,the dynamics equilibrium equation is derived,and the simplified dynamics mathematical model of the parallel manipulator is further ***,the generalized inertia matrix which can characterize the acceleration performance between joint space and operation space is further separated,and the performance indices including the dynamics dexterity,inertia coupling characteristics,energy transmission efficiency and driving force/torque balance are *** analysis results show that the proposed redundantly actuated and over-constrained 2 RPU-2 SPR parallel manipulator in comparison with the existing non-redundant one has better dynamic comprehensive performance,which can be demonstrated practically by the successful application of the parallel kinematic machine head module of the hybrid machine tool.

关键词： Redundantly actuated over-constrained parallel manipulator dynamics performance index