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STOCHASTIC OPTIMAL CONTROL OF HYSTERETIC SYSTEMS UNDER EXTERNALLY AND PARAMETRICALLY RANDOM EXCITATIONS

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Acta Mechanica Solida Sinica 2003年第1期16卷 61-66页

作者： Ying Zuguang Zhu Weiqiu (department of Mechanics,zhejiang university,hangzhou 310027,china) department of Mechanics Zhejiang University Hangzhou 310027 China

A stochastic optimal control method for nonlinear hysteretic systems under externally and/or parametrically random excitations is presented and illustrated with an example of hysteretic column system. A hysteretic system subject to random excitation is first replaced by a nonlinear non-hysteretic stochastic system. An It$\hat {\rm o}$ stochastic differential equation for the total energy of the system as a one-dimensional controlled diffusion process is derived by using the stochastic averaging method of energy envelope. A dynamical programming equation is then established based on the stochastic dynamical programming principle and solved to yield the optimal control force. Finally, the responses of uncontrolled and controlled systems are evaluated to determine the control efficacy. It is shown by numerical results that the proposed stochastic optimal control method is more effective and efficient than other optimal control methods.

关键词： stochastic optimal control hysteretic systems random vibration stochastic averaging

Strong near-epoch dependence

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Science china Mathematics 2004年第4期47卷 497-507页

作者： LIN Zhengyandepartment of Mathematics, zhejiang university, hangzhou 310028, china department of Mathematics Zhejiang University Hangzhou China

We introduce a new class of dependent sequences of random variables, which is a subclass of near-epoch dependent sequences, but can also be approximated by mixing sequences. For this kind of sequences of random variables, we call them strong nearepoch dependent sequences, a p-order, p ＞ 2, (maximum) moment inequality is established under weaker dependence sizes.

关键词： near-epoch dependence, mixingale, strong near-epoch dependence, moment inequality, convergence.

FOURIER-CHEBYSHEV COEFFICIENTS AND GAUSS-TURAN QUADRATURE WITH CHEBYSHEV WEIGHT

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Journal of Computational Mathematics 2003年第2期21卷 189-194页

作者： Shijun Yang Xinghua Wang (department of Mathematics, zhejiang university, hangzhou 310028, china) department of Mathematics Zhejiang University Hangzhou 310028

The main purpose of this paper is to derive an explicit expression for Fourier-Chebyshevcoefficientwhich is initiated by *** and***.

关键词： Fourier-Chebyshev coefficient Gauss-Turan quadrature

CHEMOENZYMATIC SYNTHESIS OF BIODEGRADABLE POLY(1’-O-VINYLADIPOYL-SUCROSE)

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Chinese Journal of Polymer Science 2002年第6期20卷 579-584页

作者： De-shui Lu Qi Wu Xian-fu Lin department of Chemistry zhejiang university hangzhou 310027, china department of Chemistry Zhejiang University Hangzhou 310027

A novel polymer containing the sucrose group was synthesized by radical polymerization from an enzymatically prepared monomer, 1'-O-vinyladipoyl-sucrose (VAS). Transesterification reaction of sucrose with divinyl adipate in anhydrous pyridine catalyzed by an alkaline protease from Bacillus subtilis at 60degreesC for 7 days gave VAS (yield 55%) without any blocking/deblocking steps. The vinyl sucrose ester could be polymerized with potassium persulfate and H2O2 as initiator to give poly(1'-O-vinyladipoyl-sucrose) with M-n = 33,000 and M-w = 53,200, M-w/M-n = 1.61. The polymer was biodegradable. After 6 days in aqueous buffer (pH 7), this alkaline protease could degrade poly(1'-O-vinyladipoyl-sucrose) to M. of ca. 1080, M-w/M-n = 3.30 (37degreesC), and M-n of ca. 5200, M-w/M-n = 2.44 (4degreesC). The polymer containing the sucrose branch would be a functional material in various application fields.

关键词： divinyladipate sucrose alkaline protease polymerization biodegradation

Start-up strategies of UASB reactor for treatment of pharmaceutical wastewater

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Journal of Environmental Sciences 2002年第2期14卷 250-254页

作者： ZHENG Ping, HU Bao lan (department of Environmental Engineering, zhejiang university, hangzhou 310029, china. department of Environmental Engineering Zhejiang University Hangzhou 310029

Two start up strategies of upflow anaerobic sludge blanket(UASB) reactor for treatment of pharmaceutical wastewater were investigated. The results showed that both of them were workable. Compared with the strategy that started up the reactor directly using chloromycetin wastewater, the strategy that started up the reactor first using mixed wastewater and then using chloromycetin wastewater could save time by 23%. When the latter strategy was adopted the development of sludge activity fluctuated more largely and its final activity was lower, but the sludge grew faster in the course of start up.

关键词： start up toxic wastewater UASB

Triptolide Inhibits Cyclooxygenase-2 and Inducible Nitric Oxide Synthase Expression in Human Colon Cancer and Leukemia Cells

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 89-95页

作者： Xiangmin TONG~# Shui'er ZHENG~# Jie JIN Lifen ZHU Yinjun LOU and Hangping YAO Institute of Hematologic Disease,department of Hematology,First Affiliated Hospital,medical school,zhejiang university,hangzhou 310003,china Institute of Hematologic Disease Department of Hematology First Affiliated HospitalMedical School Zhejiang University Hangzhou 310003 China

Triptolide （TP）,a traditional Chinese medicine,has been reported to be effective in thetreatment of autoimmune diseases and exerting antineoplastic activity in several human tumor cell *** investigates the antitumor effect of TP in human colon cancer cells （SW114） and myelocytic leukemia（K562）,and elucidates the possible molecular mechanism ***114 and K562 cells were treatedwith different doses of TP （0,5,10,20,or 50 ng/ml）.The cell viability was assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide （MTT）. Results demonstrated that TP inhibited the proliferation ofboth tumor cell lines in a dose-dependent *** further investigate its mechanisms,the productsprostaglandin E2（PGE2） and nitric oxide （NO） were measured by enzyme-linked immunosorbent assay（ELISA）.Our data showed that TP strongly inhibited the production of NO and PGE2. Consistent with theseresults,the expression of inducible NO synthase （iNOS） and cyclooxygenase-2 （COX-2） was up-regulatedboth at the mRNA level and the protein expression level,as shown by real-time RT-PCR and *** results indicated that the inhibition of the inflammatory factor COX-2 and iNOS activitycould be involved in the antitumor mechanisms of TP.

关键词： triptolide leukemia colon cancer cyclooxygenase-2 inducible nitric oxide synthase

Ground and Excited States of Bipolarons in Two and Three Dimensions

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Communications in Theoretical Physics 2007年第7期48卷 169-174页

作者： RUAN Yong-Hong CHEN Qing-Hu department of Physics,zhejiang university,hangzhou 310027,china department of Physics Zhejiang University Hangzhou 310027 China

The properties of large bipolarons in two and three dimensions are investigated by averaging over therelative wavefunction of the two electrons and using the Lee-Low-Pines-Huybrechts variational *** ground-state(GS)and excited-state energies of the Frhlich bipolaron for the whole range of electron-phonon coupling constantscan be *** energies of the first relaxed excited state(RES)and Franck-Condon(FC)excited state of thebipolaron are also *** is found that the first RES energy is lower than the FC state *** comparisonof our GS and RES energies with those in literature is also given.

关键词： bipolaron ground-state energy excited-state energy Lee-Low-Pines-Huybrechts variational method

Empirical Euclidean likelihood for general estimating equations under association dependence

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Applied Mathematics(A Journal of Chinese Universities) 2010年第4期25卷 437-446页

作者： CHEN You-you ZHANG Li-xin department of Mathematics, zhejiang university, hangzhou 310027, china department of Mathematics Zhejiang University Hangzhou China

Empirical Euclidean likelihood for general estimating equations for association dependent processes is investigated. The strong consistency and asymptotic normality of the blockwise maximum empirical Euclidean likelihood estimator are presented. We show that it is more efficient than estimator without blocking. The blockwise empirical Euclidean log-likelihood ratio asymptotically follows a chi-square distribution.

关键词： Empirical Euclidean likelihood blockwise positive association negative association.

In-situ FTIR studies of dimethyl ether adsorption on H-ZSM-5 zeolites

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Chinese Journal of Chemistry 1996年第6期14卷 497-505页

作者： JIANG, Xuan-Zhendepartment of Chemistry, zhejiang university, hangzhou, zhejiang 310027, china department of Chemistry Zhejiang University Hangzhou Zhejiang 310027 China

In situ infrared spectra of dimethyl ether adsorbed on two H-ZSM-5 zeolites are reported which are different in both lattice and extraframework aluminium contents. A number of dissociatively adsorbed dimethyl ether species associated respectively with the Bronsted acid sites, the external silanol groups and extraframework aluminium species at different temperatures are identified. In particular, dimethyl ether reacts with non acidic hydroxyl species associated with extraframework aluminium to form the third methoxy species. The distributions of hydrocarbons desorbed from a single pulse of dimethyl ether (1.0 mL) onto these zeolite samples are presented. Propene is the major product, and the yield of hydrocarbons correlates with the concentration of Bronsted acid bound methoxy groups.

关键词： In situ FTIR dimethyl ether adsorption extraframework aluminium bound methoxy species hydrocarbon products