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Charged Top-Pion Production at Hadron Colliders

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Communications in Theoretical Physics 2009年第12期52卷 1036-1040页

作者： HOU hong-sheng Department of Physics Hangzhou Normal University Hangzhou 310036 China

We studied the charged top-pion in the topcolor assisted technicolor model(TC2).If the charged top-pionsare heavy,m_(πt)>m_t+m_b,they will decay mainly via the channel π_t^+→tb^-.We also calculated the production of chargedtop-pion at the Tevatron and *** cross section can reach to 100 fb at the Tevatron and dozens of pb at the LHCdepending on the mass of the top-pion.

关键词： EW symmetry breaking charged top-pion hadron colliders

Empirical analysis on risk of security investment

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Applied Mathematics(A Journal of Chinese Universities) 2009年第2期24卷 127-134页

作者： AN Peng LI sheng-hong Antai College of Economics & Management Shanghai Jiao Tong Univ. Shanghai 200052 China Dept. of Math. Zhejiang Univ. Hangzhou 310027 China

The paper analyzes the theory and application of Markowitz Mean-Variance Model and CAPM model. Firstly, it explains the development process and standpoints of two models and deduces the whole process in detail. Then 30 stocks are choosen from Shangzheng 50 stocks and are testified whether the prices of Shanghai stocks conform to the two models. With the technique of time series and panel data analysis, the research on the stock risk and effective portfolio by ORIGIN and MATLAB software is conducted. The result shows that Shanghai stock market conforms to Markowitz Mean-Variance Model to a certain extent and can give investors reliable suggestion to gain higher return, but there is no positive relation between system risk and profit ratio and CAPM doesn＇t function well in China＇s security market.

关键词： Markowitz Mean-Variance Model Capital Asset Pricing Model time series analysis regressive analysis securities market

Analytical Method for the Wave Diffraction of Asymmetrically Arranged Breakwaters

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China Ocean Engineering 2024年第5期38卷 797-808页

作者： ZHOU Pei-xin ZHANG hong-sheng College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China Bureau of Transport of Beilun District of Ningbo Zhejiang 315800China

The layout forms of several breakwater structures can be generalized as asymmetrical arrangements in actual ***,the problem of wave diffraction around asymmetrically arranged breakwaters has not been adequately *** this study,we propose an analytical method of wave diffraction for regular waves passing through asymmetrically arranged breakwaters,and we use the Nyström method to obtain the analytical solution *** compared the results of this method with those of previous analytical solutions and with numerical results to demonstrate the validity of our *** also provided diffraction coefficient diagrams of breakwaters with different layout ***,we described the analytical expression for the problem of diffraction through long-wave incident breakwaters and presented an analysis of the relationship between the diffraction coefficients and the widths of breakwater *** analytical method presented in this study contributes to the limited literature on the theory of wave diffraction through asymmetrically arranged breakwaters.

关键词： regular waves breakwaters analytical method wave diffraction

The maximal Lyapunov exponent of a co-dimension two-bifurcation system excited by a bounded noise

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Acta Mechanica Sinica 2012年第2期28卷 511-519页

作者： sheng-hong Li Xian-Bin Liu State Key Lab of Mechanics and Control for Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics210014 NanjingChina School of Mathematics and Physics Jiangsu University of Science and Technology212003 ZhenjiangChina

In the present paper, the maximal Lyapunov ex- ponent is investigated for a co-dimension two bifurcation system that is on a three-dimensional central manifold and subjected to parametric excitation by a bounded noise. By using a perturbation method, the expressions of the invari- ant measure of a one-dimensional phase diffusion process are obtained for three cases, in which different forms of the matrix B, that is included in the noise excitation term, are assumed and then, as a result, all the three kinds of singular boundaries for one-dimensional phase diffusion process are analyzed. Via Monte-Carlo simulation, we find that the an- alytical expressions of the invariant measures meet well the numerical ones. And furthermore, the P-bifurcation behav- iors are investigated for the one-dimensional phase diffusion process. Finally, for the three cases of singular botmdaries for one-dimensional phase diffusion process, analytical ex- pressions of the maximal Lyapunov exponent are presented for the stochastic bifurcation system.

关键词： Maximal Lyapunov exponent Perturbationmethod. Bounded noise. Diffusion process

A REVISED SOLUTION OF EQUIVALENT PERMEABILITY TENSOR FOR DISCONTINUOUS FRACTURES

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Journal of Hydrodynamics 2012年第5期24卷 711-717页

作者： HE Ji CHEN sheng-hong SHAHROUR Isam State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University 430072Wuhan China Laboratoire Genie Civil et geo-Environnement University Lille 1 59650 Villeneuve d Ascq France

The equivalent permeability tensor is essential to the application of the equivalent porous media model in the numerical seepage simulation for fractured rock masses. In this paper, a revised solution of the equivalent permeability tensor is proposed to represent the influence of the fracture connectivity in discontinuous fractures. A correction coefficient is involved to reflect the com- plex seepage flow type through the rock bridge. This correction coefficient is back analyzed from single-hole packer tests, based on the Artificial Neural Network （ANN） back analysis and the Finite Element Method （FEM） seepage simulation. The limitation of this back analysis algorithm is that the number of single-hole packer tests should be equal or greater than the number of fracture sets, and three is the maximum number of the fracture sets. The proposed solution and the back analysis algorithm are applied in the permea- bility measurement and the seepage simulation for the Xiaowan arch dam foundation.

关键词： discontinuous fractures permeability tensor back analysis packer test Artificial Neural Network (ANN)

SURFACE FUNCTIONALIZATION OF POLYSTYRENE TO BIND WITH FMRF PEPTIDES FOR NOVEL BIOCOMPATIBILITY

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Chinese Journal of Polymer Science 2010年第6期28卷 895-902页

作者： Yong Chen hong-sheng Lu Peng Wang Department of Applied Chemistry School of Chemical & Environmental Engineering Shandong University of Science and Technology Qingdao 266510 China Department of Environmental Science and Technology School of Chemical & Environmental Engineering Shandong University of Science and Technology Qingdao 266510 China

A generic method was described to change surface biocompatibihty by introducing reactive functional groups onto surfaces of polymeric substrates and covalently binding them with biomolecules.A block copolymer with protected carboxylic acid functionality,poly（styrene-b-tert-butyl acrylate）（PS-PtBA）,was spin coated from solutions in toluene on a bioinert polystyrene（PS） substrate to form a bilayer structure：a surface layer of the poly（tert-butyl acrylate）（PtBA） blocks that order at the air-polymer interface and a bottom layer of the PS blocks that entangle with the PS *** thickness of the PtBA layer and the area density of tert-butyl ester groups of PtBA increased linearly with the concentration of the spin coating solution until a 2 nm saturated monolayer coverage of PtBA was achieved at the concentration of 0.4%W/*** protected carboxylic acid groups were generated by exposing the tert-butyl ester groups of PtBA to trifluoroacetic acid （TFA） for bioconjugation with FMRF peptides via amide *** yield of the bioconjugation reaction for the saturated surface was calculated to be 37.1%based on X-ray photoelectron spectroscopy（XPS） *** success of each functionalization step was demonstrated and characterized by XPS and contact angle *** polymer functionalization/modification concept can be virtually applied to any polymeric substrate by choosing appropriate functional block copolymers and biomolecules to attain novel biocompatibility.

关键词： Surface functionalization Biocompatibility Bioconjugation reaction

Integrated fault estimation and fault-tolerant control for a flexible regional aircraft

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Chinese Journal of Aeronautics 2022年第3期35卷 390-399页

作者： Yishi LIU sheng hong Enrico ZIO Jianwei LIU School of Cyber Science and Technology Beihang UniversityBeijing 100191China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Department of Energy Politecnico di MilanoMilano 20133Italy MINES ParisTech PSL Research UniversityCRCSophia Antipolis 06904France Eminent Scholar Department of Nuclear EngineeringCollege of EngineeringKyung Hee UniversitySeoul 02447South Korea

The article focuses on the design and application of an active reconfigurable controller that mitigates the effects of gust load and actuator faults on a flexible aircraft.A novel integrated adaptive output feedback scheme is investigated to address the actuator *** real-time fault values provided by the fault estimation module are considered in the reconfigurable control law to improve the fault-tolerant *** estimate values of faults and control gains are calculated by analyzing the stability of the overall *** proposed controller is simulated using a flexible aircraft model with a discrete‘1-cosine’gust,and the results show that it can effectively mitigate the wing root moments and recover the flight maneuver stability after the aircraft suffered from gusts.

关键词： Adaptive control Fault estimation Fault-tolerant control Flexible aircraft Gust load Integrated strategy

Optical flare events on the RS Canum Venaticorum star UX Arietis

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Research in Astronomy and Astrophysics 2017年第6期17卷 55-66页

作者： Dong-Tao Cao sheng-hong Gu Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China University of Chinese Academy of Sciences Beijing 100049 China

Based on long-term high-resolution spectroscopic observations obtained during five observing runs from 2001 to 2004, we study optical flare events and chromospheric activity variability of the very active RS CVn star UX Ari. By means of the spectral subtraction technique, several optical chromospheric activity indicators （including the He IDa, Na I D1, D2 doublet, Ha and Ca II IRT lines） covered in our echelle spectra were analyzed. Four large optical flare events were detected on UX Ari during our observations, which show prominent He I D3 line emission together with great enhancement in emission of the Ha and Ca II IRT lines and strong filled-in or emission reversal features in the Na ! D1, D2 doublet lines. The newly detected flares are much more energetic than previous discoveries, especially for the flare identified during the 2002 December observing run. Optical flare events on UX Ari are more likely to be observed around two quadratures of the system, except for our optical flares detected during the 2004 November observing run. Moreover, we have found rotational modulation of chromospheric activity in the Ha and Ca II IRT lines, which suggests the presence of chromospherically active longitudes over the surface of UX Ari. The change in chromospherically active longitudes among our observing runs, as well as the variation in chromospheric activity level from 2001 to 2004, indicates a long-term evolution of active regions.

关键词： stars activity - stars chromospheres - stars binaries spectroscopic -stars flare -stars individual (UX Ari)

New correlations for evaluating the equivalent bare charge mass for a cased charge

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Defence Technology（防务技术） 2023年第10期28卷 251-266页

作者： Long-kui Chen sheng-hong Huang hong-jin Chen He-ming Wen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei230026China

Munitions contain casings that consume explosive *** blast load(e.g.,peak overpressure and maximum impulse)intensity generated by ammunition explosion will be lower than that generated by a bare charge with equal *** evaluate the blast load of a cased charge under different conditions,the equivalent bare mass needs to be ***,the accuracy of existing correlations strongly depends on the empirical determination of relevant controlling parameters and lacks theoretical *** this paper,new correlations are proposed based on a more rigorous theoretical derivation,considering both the mechanical behaviors of the casing’s material and the change of the polytropic exponent during the expansion process of the explosion *** controlling parameters are attributed to the rupture radius ratio and the polytropic exponent of detonation products expansion to casing rupture *** reasonability is validated by both comprehensive numerical simulations with dynamic mechanical constitutive model and theoretical *** results calculated by the new correlation show better agreement with the experimental results than those calculated by previous correlations,and the results difference is explained in more consistency with the thermos-physical properties of the charge and mechanical behaviors of casing ***,the correlation of the cased-to-bare impulse ratio is also theoretically improved,providing a more accurate theoretical basis for both the equivalent bare mass and impulse evaluation for a cased charge.

关键词： Cased charge Energy conservation Equivalent bare charge Fracture strain Polytropic exponent