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Copositive approximation by rational functions with prescribed numerator degree

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Applied Mathematics(A Journal of Chinese Universities) 2009年第4期24卷 411-416页

作者： YU dan-sheng ZHOU Song-ping Department of Mathematics Hangzhou Normal University Hangzhou 310036 China Department of Mathematics Statistic and Computer Science St. Francis Xaiver University Antigonish Nova Scotia Canada B2G 2W5 Institute of Mathematics Zhejiang Sci-Tech University Hangzhou 310028 China

The paper proves that, if f（x） ∈ L^p[-1,1],1≤p〈∞ ,changes sign I times in （-1, 1）,then there exists a real rational function r（x） ∈ Rn^（2μ-1）l which is eopositive with f（x）, such that the following Jackson type estimate ｜｜f-r｜｜p≤Cδl^2μωφ（f,1/n）p holds, where μ is a natural number ≥3/2＋1/p, and Cδ is a positive constant depending only on δ.

关键词： copositive approximation rational functions approximation rate

Seismic response analysis of damper-connected adjacent structures with stochastic parameters

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第6期11卷 402-414页

作者： Dong-dong GE Hong-ping ZHU dan-sheng WANG Min-shui HUANG School of Civil Engineering and Mechanics Huazhong University of Seience and Technology Wuhan 430074 China Hubei Key Laboratory of Control Structure Huazhong University of Science and Technology Wuhan 430074 China Transportation Research Center Wuhan Institute of Technology Wuhan 430073 China

Dynamic response analysis of damper connected adjacent multi-story structures with uncertain parameters is carried out.A formula of the multi degree of freedom(MDOF) for the structure-damper system with stochastic parameters is *** uncertainties of mass and stiffness are taken into consideration *** ground acceleration is represented by Kanai-Tajimi filtered non-stationary *** mean square random responses of structural displacement and story drift are chosen as the optimization *** variations of mean square responses of top floor displacements and bottom story drifts in neighboring structures with the damper stiffness and damping coefficient are analyzed in *** the parametric study,the acquiring optimum parameters of damper are regarded as numerical ***,a reducing order model of the MDOF system for adjacent structures with mean parameters is *** explicit expressions for determining optimal parameters of Kelvin model-defined damper which is used to connect adjacent single degree of freedom(SDOF) structures subjected to a white-noise excitation are employed to achieve the appropriate damper parameters,which are called theory *** a comparative study,it can be found that the theory values of damper parameters are consistent with the results based on extensive parametric *** analytical results can be obtained by using the first natural frequencies and the total mass of the adjacent deterministic structures with mean *** analytical formulas can be used to find appropriate parameters of damper between adjacent structures for engineering *** performance of damper is investigated on the basis of mitigations of mean square random responses of inter-story drifts,displacements and accelerations in adjacent *** numerical results demonstrate the robustness of coupled building control strategies.

关键词： Adjacent structures Passive control Stochastic parameters Seismic response

Synthesis,Structure and Optical Properties of Cerium(Ⅲ) Triphosphate CeP_3O_9

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Chinese Journal of Structural Chemistry 2007年第3期26卷 338-346页

作者： TONG Hua-Nan ZHANG Hao CHENG Wen-dan WU Dong-sheng GONG Ya-Jing ZHU Jing HUANG Shu-Ping ZHAO dan State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The single crystal and crystallized powder of triphosphate CeP3O9 have been synthesized, and the space group of CeP3O9has been determined to be C2221 with the cell parameters ofa = 8.6059, b = 11.2437, c = 7.3518 A, V= 711.4（3） A^3, Z= 4, D,. = 3.520 g/cm^3, F（000） = 700, R = 0.0377 and wR = 0.0930. The absorption and emission spectra have been measured, for which the strongest absorption and emission peaks are located at 280 and 320 nm, respectively. The density of state （DOS） and dielectric function have been calculated by the DFT method. The crystal is transparent provided the wavelength is larger than 341 nm, and the observed ultraviolet cut-off edge is at about 350 nm for a polycrystalline power sample. It is possible that the triphosphate CeP3O9 will become an ultraviolet emission material.

关键词： crystal structure phosphate optical properties density of states

Quantile Regression for Thinning-based INAR(1)Models of Time Series of Counts

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Acta Mathematicae Applicatae Sinica 2021年第2期37卷 264-277页

作者： dan-shu sheng De-hui WANG Kai YANG Zi-ang WU School of Mathematics Jilin UniversityChangchun 130012China School of Economics Liaoning UniversityShenyang 110036China School of Mathematics and Statistics Changchun University of TechnologyChangchun 130012China

In this paper,we develop the quantile regression(QR)estimation for the first-order integer-valued autoregressive(INAR(1))models by defining the smoothing INAR(1)*** method is used to derive the QR estimators for the autoregressive coefficient and the quantile of *** consistency and asymptotic normality of the proposed estimators are *** performances of the proposed estimation procedures are evaluated by Monte Carlo *** results show that the proposed procedures perform well for simulations and a real data application.

关键词： INAR(1)process quantile regression parameter estimation jittering

Preface to the special issue on aluminum alloys for transportation

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Journal of Central South University 2022年第3期29卷 741-743页

作者： YU Hai-liang LIU sheng-dan CAO Ling-fei GUO Ming-xing Light Alloy Research Institute Central South UniversityChangsha 410083China School of Materials and Engineering Central South UniversityChangsha 410083China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

Aluminum alloys have been used widely as structural materials in the field of aerospace,high speed train and car *** to their advantages such as low density,high strength,and good corrosion *** properties of these materials can increase the reliability,durability and life of the structural components,and decrease the cost and CO_(2) *** special issue focuses on the recent development of advanced aluminum alloys applied in the transportation field,particularly aerospace,train and car.

关键词： alloys corrosion strength

Low-dose clozapine-related seizure: A case report and literature review

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World Journal of Clinical Cases 2021年第20期9卷 5611-5620页

作者： dan-sheng Le Heng Su Zheng-Luan Liao En-Yan Yu The Second Clinical Medical College Zhejiang Chinese Medicine UniversityHangzhou 310051Zhejiang ProvinceChina Department of Psychiatry Zhejiang Provincial People’s HospitalHangzhou 310000Zhejiang ProvinceChina Department of Psychiatry The Cancer Hospital of the University of Chinese Academy of Sciences(Zhejiang Cancer Hospital)Institute of Basic Medicine and CancerChinese Academy of SciencesHangzhou 310022Zhejiang ProvinceChina

BACKGROUND Treatment-resistant schizophrenia is a severe form of schizophrenia characterized by poor response to at least two antipsychotic drugs and is typically treated with ***,clozapine lowers the epileptic threshold,leading to seizures,which are severe side effects of antipsychotics that result in multiple ***-related seizures are generally considered to be dose-dependent and especially rare in the low-dose(150-300 mg/d)clozapine treated *** to clinical rarity,little is known about its clinical characteristics and *** SUMMARY A 62-year-old Chinese man with a 40-year history of treatment-resistant schizophrenia presented to the Emergency Department with symptoms of myoclonus,consciousness disturbance and vomiting after taking 125 mg *** admission,the patient had a suddenly generalized tonic-clonic seizure lasting for about half a minute with persistent disturbance of consciousness,fever,cough and bloody sputum,which was considered to be low-dose clozapine-related *** antiepileptic and multiple anti-infection treatments,the patient was discharged without epileptic or psychotic *** Our aim is to highlight the early prevention and optimal treatment of clozapine related seizure through case analysis and literature review.

关键词： Seizure Treatment-resistant schizophrenia Antipsychotic Antiepileptic Electroconvulsive therapy Case report

Analysis of the Q-T Dispersion and T Wave Alternans in Patients with Epilepsy

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Yangtze Medicine 2017年第2期1卷 109-116页

作者： dan sheng Xianglin Cheng Department of Neurology the Clinical Medicine School of Yangtze University the First Affiliated Hospital of Yangtze

Objectives: There is a high rate of sudden death in epilepsy patients, part of which is sudden cardiac death. By investigating ECG T wave alternans and Q-T dispersion changes of epilepsy patients, we may predict the possibility of the occurrence of sudden death and provide basis for clinical prevention. Methods: Selecting 587 cases of epilepsy patients as the study group, 672 same period cases of healthy persons as the control group;Analyzing the effect of epilepsy on ECG T wave alternans and Q-T dispersion with the standard 12 lead ECG. Results: The study group had a significantly prolonged Q-T dispersion and an increased incidence of T wave alternans than that of the control group;Compared with other seizure types, tonic clonic seizure and absence seizure had a significantly prolonged Q-T dispersion and an increased occurrence rate of T wave alternans. Conclusions: Epilepsy patients ECG T wave alternans and Q-T dispersion has higher abnormal rate, and are prone to sudden cardiac death;Routine ECG(RECG) T wave alternans and Q-T dispersion changes can provide guidance for clinical prevention of sudden unexpected death in epilepsy (SUDEP).

关键词： Epilepsy T Wave Alternans Q-T Dispersion

X-RAY STRUCTURE AND MOLECULAR MECHANICS CALCULA-TIONS OF N-(2-CHLOROPHENYL)-2-PYRIDINECAR-BOTHIOAMIDE

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Chinese Journal of Structural Chemistry 1992年第1期 12-16页

作者： Chen Ming-dan Huang Ming-sheng Hu sheng-ZhiDepartment of Chemistry , Xiamen University , Xiamen 361005

C12H9N2SCl, Mr= 248. 74, monoclinic, P21/n, a = 3. 902(2), b = 11.547(1), c = 25. 132(4)(?), β =93. 71(2)°, V = 1131. 1(?)3, Z = 4, Dc = 1.461, Do= 1. 45gcm-3, λ(MoKα) = 0, 71073A, μ = 4.84cm-1, F(000) = 512, R = 0. 041 for 1755 unique observed reflections. In comparison of the title molecular structure with that of N-(2-methylphenyl)-2-Pyridinecarbothipamide, the difference is insignificant. Intramolecular hydrogen bonds and short contacts are formed to the utmost extent, and the intermolecular hydrogen bonds such as C - H… S and C-H…Cl play an important role in the molecular packing. Molecular mechanics calculations (MMPM) is informative on the feature of the molecular conformation observed.

关键词： X-RAY STRUCTURE AND MOLECULAR MECHANICS CALCULA-TIONS OF N CHLOROPHENYL PYRIDINECAR-BOTHIOAMIDE

Antitumor Compound Identification from Zanthoxylum bungeanum Essential Oil Based on Composition-activity Relationship

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Chemical Research in Chinese Universities 2013年第6期29卷 1068-1071页

作者： LI Zi-dan HAN sheng-nan JIANG Jian-lan ZHANG Xiao-hang LI Yan CHEN Hao YUAN Ying-jin Key Laboratory of Systems Bioengineering Ministry of Education Tianjin Key Laboratory of Biological and Pharmaceutical Engineering Department of Pharmaceutical Engineering School of Chemical Engineering and Technology Tianjin University Tianjin 300072 P.R.China

The chemical composition of Zanthoxylum bungeanum（Z bungeanum） essential oi1（39 batches） was analyzed by gas chromatography-mass spectrometry（GC-MS） analysis（23 ingredients）, and the antitumor activity against HeLa cells was detected via the MTT[3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide] assay. Two composition-activity relationship（CAR） models, generalized regression neural network（GRNN） and support vector regression（SVR） were respectively used to calculate the mean impact value（MIV） so as to identify bioactive com- pounds. Among them 9 ingredients（peaks 4, 15, 7, 8, 13, 3, 16, 9 and 11） were selected due to their high absolute MIVs. All of them have been confirmed with potential antitumor activity by previous researches. The CAR model combined with MIV was expected to be a credible tool for the active compound identification from herbs.

关键词： Zanthoxylum bungeanum essential oil HeLa cell Composition-activity relationship model Active compound identification