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Weighted weak type (1,1) estimate for the Christ-Journé type commutator

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science China Mathematics 2018年第3期61卷 517-534页

作者： Yong Ding Xudong lai school of Mathematical sciences Beijing Normal University Beijing 100875 China Institute for Advanced study in Mathematics Harbin Institute of Technology Harbin 150001 China

Let k be the Calderón-Zygmund convolution kernel on R^d(d≥2).Christ and Journé defined the commutator associated with k and a∈L~∞(R^d)by T_af(x)=p.v.∫_(R^d)k(x-y)m_x,y^a·f(y)dy,which is an extension of the classical Calderón commutator. In this paper, we show that T_a is weighted weak type(1,1) bounded with A,1 weight for d≥2.

关键词： Christ-Journe type commutator weighted weak type(1 1) A1 weight

DNA-chip-based dynamic broadcast encryption scheme with constant-size ciphertexts and decryption keys

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science China(Information sciences) 2014年第9期57卷 126-135页

作者： FANG XiWen lai XueJia Department of Computer science and Engineering Shanghai Jiao Tong University

In this paper we present DNA-DBE,a DNA-chip-based dynamic broadcast encryption *** our scheme,new users can join dynamically without modification of other users’decryption *** the ciphertext or the decryption key is of *** secrecy is achieved in DNA-DBE:if new users join the system dynamically,they will not be able to retrieve past *** security of our scheme relies on hard biological problems,which are immune to attacks of new computing technologies in the *** exists a special feature in DNA–based cryptosystems,*** set of encryption keys and the set of decryption keys have a many-to-many *** implementation of more complicated DNA cryptosystems taking advantage of this special feature has been previously left as an open *** DNA-DBE system is a solution to this open problem,which is also the first exploration of DNA based group-oriented encryption system.

关键词： DNA cryptography dynamic broadcast encryption group oriented cryptography DNA chip cryptology

synthesis, Characterization and Control of Proportion of Polymorph C in ITQ-16 and ITQ-17 Films

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Chemical Research in Chinese Universities 2016年第6期32卷 895-901页

作者： CHEN Yanli FENG lai College of Physics Optoelectronics and Enevgy Soochow University Suzhou 215006 P. R. China school of Materials science and Engineering Tianjin University of Technology Tianjin 300384 P. R. China

Continuous ITQ-16 and ITQ-17 films on silicon wafer were prepared in fluoride media using TEAOH asorganic structure-directing agent. The proportion ofpolymorph C in the as-synthesized ITQ-16 and ITQ-17 films wasdetermined via X-ray diffraction characterization. The proportion of polymorph C in the ITQ-16 and 1TQ-17 filmswas controlled via optimizing the compositions of the reaction mixtures and reaction conditions, such as varyingthe si/Ge molar ratio and adding n-propyl alcohol as a solvent in the reaction mixture, The Ge atoms in the reactionmedia strongly increased the crystallization of polymorph C in ITQ-16 and ITQ-17 films. Moreover, the stabilizingand buffering effect of n-propyl alcohol on crystal growth further enhanced the proportion of polymorph C in theITQ-16 and ITQ-17 films. For potential catalytic applications, A1 was incorporated into the framework ofpolymorphC, and a pure phase of polymorph C in Al-ITQ-17 film was achieved from the synthesis gel in the n-propyl alcohol phase.

关键词： Zeolite beta ITQ-16 ITQ-17 Polymorph C

Low cycle fatigue properties and cyclic deformation behavior of as-extruded AZ31 magnesium alloy

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Transactions of Nonferrous Metals society of China 2010年第B07期20卷 533-539页

作者： s.kWON k.sONG k.s.sHIN s.I.kWUN Department of Materials science and Engineering Korea University school of Materials science and Engineering Seoul National University

The low cycle fatigue(LCF)properties of as-extruded AZ31 Mg alloy were investigated under total strain amplitudes in the range of 0.4%-1.2%with strain rate of 1×10- 2s -*** to the twinning effect in compression during loading and the detwinning effect during unloading,the alloy showed an asymmetric hysteresis *** cyclic stress response exhibited cyclic hardening at high total strain *** cyclic deformation behaviors were discussed using the Coffin-Manson plot,which divided the plastic strain amplitudes into the tension side and the compression *** the LCF tests that were started from either tension or compression under a total strain amplitude of 1.0%,the interaction between the twinning effect and dislocation was *** twinning effect during the LCF test and the variation of the dislocation density were investigated using optical microscopy and transmission electron microscopy,respectively.

关键词： AZ31 magnesium alloy low cycle fatigue twinning dislocation

Robust N−k security-constrained Optimal Power Flow Incorporating Preventive and Corrective Generation Dispatch to Improve Power system Reliability

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CsEE Journal of Power and Energy systems 2023年第1期9卷 351-364页

作者： Liping Huang Chun sing lai Zhuoli Zhao Guangya Yang Bang Zhong Loi Lei lai school of Automation Guangdong University of TechnologyGuangzhou 510006China school of Automation Guangdong University of TechnologyGuangzhou 510006Chinaand also with the Department of Electronic and Electrical EngineeringBrunel University LondonLondonUB83PHUK Center for Electric Power system and Energy Department of Electrical EngineeringTechnical University of DenmarkKongens Lyngby 2800Demark Zhaoqing Power supply Bureau Guangdong Power Grid CompanyChina Southern Power GridZhaoqing 526020China

As extreme weather events have become more frequent in recent years,improving the resilience and reliability of power systems has become an important area of *** this paper,a robust preventive-corrective security-constrained optimal power flow(RO-PCsCOPF)model is proposed to improve power system reliability under N−k *** the short-term emergency limit(sTL)and the long-term operating limit(LTL)of the post-contingency power flow on the branch are *** with the existing robust corrective sCOPF model that only considers sTL or LTL,the proposed ROPCsCOPF model can achieve a more reliable generation dispatch *** addition,this paper also summarizes and compares the solution methods for solving the N−k sCOPF *** computational efficiency of the classical Benders decomposition(BD)method,robust optimization(RO)method,and line outage distribution factor(LODF)method are investigated on the IEEE 24-bus Reliability Test system and 118-bus *** results show that the BD method has the worst computation *** RO method and the LODF method have comparable ***,the LODF method can only be used for the preventive sCOPF and not for the corrective *** RO method can be used for both.

关键词： Benders cut bender decomposition line outage distribution factor N−k security criterion optimal power flow power system reliability resilience robust optimization

U-Pb Ages and Hf Isotope of Zircons from a Carbonatite Dyke in the Bayan Obo Fe-REE Deposit in Inner Mongolia: its Geological significance

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Acta Geologica sinica(English Edition) 2019年第6期93卷 1783-1796页

作者： lai Xiaodong YANG Xiaoyong school of Environmental and Chemical Engineering Foshan UniversityFoshanGuangdong 528225China CAs key Laboratory of Crust-Mantle Materials and Environments University of Science and Technology of ChinaHefei 230026China

Detailed studies on U-Pb ages and Hf isotope have been carried out in zircons from a carbonatite dyke associated with the Bayan Obo giant REE-Nb-Fe deposit,northern margin of the North China Craton(NCC),which provide insights into the plate tectonic in *** of small amounts of zircons extracted from a large sample of the Wu carbonatite dyke have yielded two ages of late Archaean and late Paleoproterozoic(with mean 207 Pb/206 Pb ages of 2521±25 Ma and 1921±14 Ma,respectively).Mineral inclusions in the zircon identified by Raman spectroscopy are all silicate minerals,and none of the zircon grains has the extremely high Th/U characteristic of carbonatite,which are consistent with crystallization of the zircon from silicate,and the zircon is suggested to be derived from trapped basement *** isotopes in the zircon from the studied carbonatite are different from grain to grain,suggesting the zircons were not all formed in one single *** ofεHf(t)values are compatible with ancient crustal sources with limited juvenile *** Hf data and their TDM2 values also suggest a juvenile continental growth in Paleoproterozoic during the period of 1940–1957 *** data demonstrate the major crustal growth during the Paleoproterozoic in the northern margin of the NCC,coeval with the assembly of the supercontinent Columbia,and provide insights into the plate tectonic of the NCC in Paleoproterozoic.

关键词： crustal growth zircon U-Pb age Hf isotope Bayan Obo North China Craton

A higher order lattice BGk model for simulating some nonlinear partial differential equations

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science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 1053-1061页

作者： lai HuiLin MA ChangFeng school of Mathematics and Computer science Fujian Normal UniversityFuzhou 350007China

In this paper, we consider a one-dimensional nonlinear partial differential equation that has the form ut + αuux + βunux - γuxx + δuxxx = F(u). A higher order lattice Bhatnager-Gross-krook (BGk) model with an amending-function is proposed. With the Chapman-Enskog expansion, different kinds of nonlinear partial differential equations are recovered correctly from the continuous Boltzmann equation. The numerical results show that this method is very effective.

关键词： nonlinear partial differential equation lattice Boltzmann model multi-scale technique Taylor series expansion Chapman-Enskog expansion

An in situ monitoring method for PECVD process equipment condition

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Plasma science and Technology 2019年第6期21卷 15-22页

作者： G kANG s AN k kIM s HONG Department of Electronic Engineering Myongji University Yongin 17058 Republic of Korea

A key to successful consistent plasma processing is maintaining a consistent process chamber condition over a certain production *** alleviate the concern,in situ process monitoring sensors are employed to investigate the plasma chamber conditions of both the deposition step with direct plasma and the cleaning step with a remote plasma *** situ sensors are optical emission spectroscopy (OEs),optical plasma monitoring sensors (OPMs),voltage current probes (Ⅵ-probes),and self-plasma OEs (sP-OEs).During the deposition,we perform the monitoring of a plasma condition associated with the applied RF power via OEs,OPMs,and a Ⅵ-*** the chamber cleaning step using a remote plasma system does not allow plasma monitoring through the sidewall because the plasma is not formed in the process chamber,thus we employed sP-OEs to monitor the by-product gas chemistry during the chamber cleaning process *** monitoring results with some useful applications,such as arc detection,part failure detection,and cleaning process chemistry analysis,are presented in this *** use of in situ sensors with proper combination can help to understand the plasma process better,to achieve more precise control of plasma processing.

关键词： in situ monitoring sensor advanced equipment control

Rheological fluid motion in tube by metachronal waves of cilia

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Applied Mathematics and Mechanics(English Edition) 2017年第3期38卷 393-410页

作者： s.MAITI s.k.PANDEY Department of Mathematical sciences Indian Institute of Technology (BHU) Department of Mathematics The LNM Institute of Information Technology

This paper presents a theoretical study of a non-linear rheological fluid transport in an axisymmetric tube by cilia. An attempt has been made to explain the role of cilia motion in the transport of fluid through the ductus efferent of the male reproductive tract. The Ostwald-de Waele power-law viscous fluid is considered to represent the rheological fluid. We analyze pumping by means of a sequence of cilia beats from rowto-row of cilia in a given row of cells and from one row of cells to the next(metachronal wave movement). For this purpose, we consider the conditions that the corresponding Reynolds number is small enough for inertial effects to be negligible, and the wavelengthto-diameter ratio is large enough so that the pressure can be considered uniform over the cross section. Analyses and computations of the fluid motion reveal that the time-average flow rate depends on ε, a non-dimensional measure involving the mean radius a of the tube and the cilia length. Thus, the flow rate significantly varies with the cilia ***, the flow rate has been reported to be close to the estimated value 6 × 10ml/h for human efferent ducts if ε is near 0.4. The estimated value was suggested by Lardner and shack(Lardner, T. J. and shack, W. J. Cilia transport. Bulletin of Mathematical Biology, 34, 325–335(1972)) for human based on the experimental observations of flow rates in efferent ducts of other animals, e.g., rat, ram, and bull. In addition, the nature of the rheological fluid, i.e., the value of the fluid index n strongly influences various flow-governed characteristics. An interesting feature of this paper is that the pumping improves the thickening behavior for small values of ε or in free pumping(?P = 0) and pumping(?P > 0) regions.

关键词： non-Newtonian fluid cilia movement metachronal wave volumetric flow flow reversal velocity at wave crest and trough