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A Filter Line Search Algorithm Based on an Inexact Newton Method for Nonconvex Equality Constrained Optimization

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Acta Mathematicae Applicatae Sinica 2017年第3期33卷 687-698页

作者： zhu-jun WANG De-tong zhu Cun-yun NIE College of Science Hunan Institute of Engineering College of Mathematics and Science Shanghai Normal University

We propose an inexact Newton method with a filter line search algorithm for nonconvex equality constrained optimization. Inexact Newton＇s methods are needed for large-scale applications which the iteration matrix cannot be explicitly formed or factored. We incorporate inexact Newton strategies in filter line search, yielding algorithm that can ensure global convergence. An analysis of the global behavior of the algorithm and numerical results on a collection of test problems are presented.

关键词： nonconvex constrained optimization filter line search inexact Newton method

A Probability Driven Quadri-Stage Contention Protocol for Mobile Ad Hoc Networks

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Chinese Journal of Electronics 2014年第3期23卷 591-597页

作者： LIU yun MA Yongqiang zhu Bocheng School of Electronics Engineering and Computer Science Peking University

The paper proposes a new contention based Time division multiple access(TDMA) Medium access control(MAC) protocol in wireless ad hoc networks,which can be termed Quadri-stage contention protocol(QSCP). The QSCP protocol is free of both the "hidden terminal" and the "exposed terminal" problems. It is distributive and arbitrarily scalable. In the dedicated contention stage, nodes exchange their "Normalized accumulation and dissipation rate of payload(NADROP)" messages in 2-hop neighborhood, and then run a contention probability calculation algorithm to decide the probability of sending a contention frame. The algorithm guarantees that the number of time slot reserved by a node is proportional to its NADROP value, which can remarkably improve the end-to-end throughput when network load is heavy, and is more efficient in energy consumption. The simulation results demonstrate that QSCP performs better than the existing protocols.

关键词： Mobile ad hoc network TDMA MAC Contention probability Data payload QSCP

Determination of Constituents in hair Dyes by Reversed-phase High-Performance Liquid Chromatography

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Chinese Chemical Letters 2000年第6期11卷 471-472页

作者： Bao hai SHAO Jian Wei YAN Xiu zhu XU Xiao yun FU(Department of Chemistry, Zhejiang University, Hangzhou 310027) Department of Chemistry Zhejiang University Hangzhou 310027 China

A reversed-phase high-performance liquid chromatographic method for the separation and quantitation of 1,4-phenylenediamine, 4-aminophenol, 3-aminophenol, 1,3-benzendiol and 2,6-phenylenediamine in hair dyes was developed. The separation was carried out on a mu-Bondapak C-18 column with methanol-water containing 0.1% triethylamine and 0.02 mol/L NH4Ac (pH=5.20) (10:90. vol./vol.) as the mobile phase. Two real samples were analyzed.

关键词： hair dyes 1,4-phenylenediamine 4-aminophenol 3-aminophenol 1,3-benzendiol 2,6-phenylenediamine HPLC

Dimethyl phthalate biodegradation by Dunaliella tertiolecta

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Journal of Environmental Sciences 1998年第3期10卷 41-46页

作者： Yan hai Liu yun xia Research Center for Eco Environmental Sciences Chinese Academy of SciencesBeijing 100085China

unaliella tertiolecta has an ability to biodegrade dimethyl phthalate(DMP) was found in this study, and the average of the biodegradation rates were 113 mg/(L·d) and 305 mg/(L·d), and the average of the phthalic acid (PA) production rates were 15 mg/(L·d) and 36 mg/(L·d), for initial 100 mg/L and 300 mg/L DMP, respectively. The larger amount of accumulation by D. tertiolecta under higher DMP concentration may be responsible for the increase of biodegradation rate, and one of products of DMP biodegradation by D. tertiolecta may be PA. By fitting the process of DMP biodegradation by D. tertiolecta with a kinetic equation newly suggested, the standard deviations between calculated and observed values were 25 mg/L and 57 mg/L, respectively.

关键词： dimethyl phthalate dunaliella tertiolecta biodegradation.

Superior ligand for Pd(Ⅱ)-catalyzed enantioselective arylation of C(sp^3)-H bonds:chiral acetyl protected aminoethyl quinoline

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Science China Chemistry 2017年第2期60卷 165-166页

作者： Zheng-Yang Xu hai-zhu Yu Yao Fu Collaborative Innovation Centre of Chemistry for Energy Materials CAS Key Laboratory of Urban Pollutant Conversion Department of Chemistry University of Science and Technology of ChinaHefei 230026China Department of Chemistry and Centre for Atomic Engineering of Advanced Materials Anhui UniversityHefei 230601China

Enantioselective functionalization of prochiral C-H bonds is a highly attractive strategy for the construction of chiral *** extensive efforts[1],enantioselective C（sp3）-H functionalization still remains challenging at *** instance,although enantioselective C-H functionalization via desymmetrization of two carbon centers has been accomplished with Pd catalysis and a directing group,differenciation of the prochiral C-H bonds on one methylene carbon center has rarely been *** a different front,introduction of a transient chiral directing group is expected to be useful in enantioselective C-H arylation of C（sp2）-H ***,

关键词： Aromatic compounds Catalysis Chemical reactions Computation theory Density functional theory Enantioselectivity Ligands

Tempura-like carbon/carbon composite as advanced anode materials for K-ion batteries

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Journal of Energy Chemistry 2021年第8期30卷 589-598,I0012页

作者： Hao-Jie Liang Zhen-Yi Gu Xue-Ying Zheng Wen-Hao Li Ling-yun zhu Zhong-Hui Sun yun-Feng Meng hai-Yue Yu Xian-Kun Hou Xing-Long Wu MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China Key Laboratory of Preparation and Application of Environmental Friendly Materials(Jilin Normal University) Ministry of EducationChangchun 130103China Institute of New Energy for Vehicles Tongji University201804 ShanghaiChina CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology100190 BeijingChina Center for Advanced Analytical Science School of Chemistry and Chemical EngineeringMOE Key Laboratory for Water Quality and Conservation of the Pearl River DeltaGuangzhou UniversityGuangzhou 510006China National&Local United Engineering Laboratory for Power Batteries Faculty of ChemistryNortheast Normal UniversityChangchun 130024China

Graphite as a promising anode candidate of K-ion batteries(KIBs)has been increasingly studied currently,but corresponding rate performance and cycling stability are usually inferior to amorphous carbon *** protect the layer structure and further boost performance,tempura-like carbon/carbon nanocomposite of graphite@pitch-derived S-doped carbon(G@PSC)is designed and prepared by a facile and low-temperature modified molten salt *** robust encapsulation structure makes their respective advantages complementary to each other,showing mutual promotion of electrochemical performances caused by synergy *** a result,the G@PSC electrode is applied in KIBs,delivering impressive rate capabilities(465,408,370,332,290,and 227 m A h g^(-1)at 0.05,0.2,0.5,1,2,and 5 A g^(-1))and ultralong cyclic stability(163 m A g^(-1)remaining even after 8000 cycles at 2 A g^(-1)).On basis of ex-situ studies,the sectionalized K-storage mechanism with adsorption(pseudocapacitance caused by S doping)-intercalation(pitch-derived carbon and graphite)pattern is ***,the exact insights into remarkable rate performances are taken by electrochemical kinetics tests and density functional theory *** a word,this study adopts a facile method to synthesize high-performance carbon/carbon nanocomposite and is of practical significance for development of carbonaceous anode in KIBs.

关键词： K-ion batteries Anode materials Carbon/carbon composite S doping Cyclic stability DFT calculation

Exact relations for two-photon-exchange effect in elastic ep scattering by dispersion relation and hadronic model

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Chinese Physics C 2021年第7期45卷 74-81页

作者： Hui-yun Cao hai-Qing Zhou School of Physics Southeast UniversityNanjing 211189China

The two-photon-exchange(TPE)effect plays a key role in extracting the form factors(FFs)of the *** this work,we discuss several exact properties of the TPE effect in the elastic ep *** taking four low energy interactions as examples,we analyze kinematical singularities,asymptotic behaviors,and branch cuts of TPE *** analytical expressions clearly indicate several exact relations between the dispersion relation(DR)and hadronic model(HM)*** suggests that the two methods must be modified to general forms,while novel forms yield the same *** the modification,new DRs include a non-trivial term with two ***,new DRs automatically include contributions due to the seagull interaction,meson-exchange effect,contact interactions,and off-shell *** analyze the elastic e^(±)}p scattering data sets,the new forms must be used.

关键词： dispersion relation form factor two-photon-exchange

Iterative learning control of SOFC based on ARX identification model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1921-1927页

作者： HUO hai-bo zhu Xin-jian TU Heng-yong Fuel Cell Research lnstitute Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

This paper presents an application of iterative learning control (ILC) technique to the voltage control of solid oxide fuel cell (SOFC) stack. To meet the demands of the control system design, an autoregressive model with exogenous input (ARX) is established. Firstly, by regulating the variation of the hydrogen flow rate proportional to that of the current, the fuel utilization of the SOFC is kept within its admissible range. Then, based on the ARX model, three kinds of ILC controllers, i.e. P-, PI- and PD-type are designed to keep the voltage at a desired level. Simulation results demonstrate the potential of the ARX model applied to the control of the SOFC, and prove the excellence of the ILC controllers for the voltage control of the SOFC.

关键词： Autoregressive model with exogenous input (ARX) lterative learning control (ILC) Solid oxide fuel cell (SOFC) Identification

Simulation of three-phase flow and lance height effect on the cavity shape

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International Journal of Minerals,Metallurgy and Materials 2014年第6期21卷 523-530页

作者： Kai Dong Rong zhu Wei Gao Fu-hai Liu School of Mechanical Engineering University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing Shougang Design Institute

A three-dimensional computational fluid dynamics （CFD） model was developed to simulate a 150-t top-blown converter. The ef-fect of different lance heights on the cavity shape was investigated using the volume of fluid （VOF） method. Numerical simulation results can reflect the actual molten bath surface waves impinged by the supersonic oxygen jets. With increasing lance height, the cavity depth de-creases, and the cavity area, varying like a parabola, increases and then decreases. The cavity area maximizes at the lance height of 1.3 m. Under the three different lance heights simulated in this study, all of the largest impact velocities at the molten bath surface are between 50 m/s and 100 m/s.

关键词： metallurgical furnaces basic oxygen converters lance height cavity shape computational fluid dynamics computer simulation