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Computer Modeling in Engineering & Sciences 2015年第1期104卷 41-68页

作者： f.Z.Chen h.f.Qiang W.R.Gao 601 Staff Room Xi’an Hi–Tech InstituteXi’anShanxiPRCPC 710025

A coupled method describing gas–solid two-phase flow has been proposed to numerically study the bubble formation at a single orifice in gas-fluidized *** particles are traced with smoothed particle hydrodynamics,whereas gas phase is discretized by finite volume *** force,gas pressure gradient,and volume fraction are used to couple the two *** effect of injection velocities,particle sizes,and particle densities on bubble growth is analyzed using the coupled *** simulation results,obtained for two-dimensional geometries,include the shape and diameter size of a bubble as a function of time;such results are compared with experimental data,previous numerical results,and other approximate model predictions reported in the ***,the flow profiles of gas and particle phases and the temperature distribution by the heat transfer model around the forming bubble are also *** results show that the coupled method efficiently describes of the bubble formation in fluidized *** proposed method is applicable for solving gas–solid two-phase flow in fluidization.

关键词： coupled method smoothed particle hydrodynamics finite volumemethod bubble formation heat transfer fluidization

ANOMALOUS EffECT Of PRESSURE ON ThE CURIE TEMPERATURE IN MEChANICALLY ALLOYED fe-Ni INVAR

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 205-209页

作者： X.h. Wei f. Ono Department of Electronic Science Huizhou University Huizhou 516007 China Department of Physics Okayama University 3-1-1 Tsushima-Naka Okayama 700-8530 Japan

Measurements of magnetic susceptibility in mechanically alloyed fe-Ni Invar alloys were taken under pressures up to 7.5GPa. The rate of decrease in the Curie temperature for 700℃ annealed specimen was larger than that annealed at 1000℃. This result can be explained by considering the fact that the width of the concentration fluctuation becomes larger in the specimen annealed at lower temperature.

关键词： invar alloy fe-Ni, mechanical alloying Curie temperature

PARTIAL REGULARITY fOR OPTIMAL DESIGN PROBLEMS INVOLVING BOTh BULK AND SURfACE ENERGIES

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Chinese Annals of Mathematics,Series B 1999年第2期20卷 137-158页

作者： f.h.LIN R.V.KOhN CourantInstituteofMathematicalSciences USA projectsupportedbytheNationalNaturalSciencefoundationofUSA

This paper studies a class of variational problems which involving both bulk and surfaceenergies. The bulk energy is of Dirichlet type though it can be in very general forms allowingunknowns to be scalar or *** surface energy is an arbitrary elliptic parametric integralwhich is defined on a free interface. One also allows other constraints such as volumes of partitioning sets. One establishes the existence and regularity theory, in particular, the regularityof the free interface of such problems.

关键词： Partial regularity Optimal design problem Nonlinear variational problems

Predicting Soil Moisture Characteristic Curves from Continuous Particle-Size Distribution Data

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Pedosphere 2013年第1期23卷 70-80页

作者： M.h.MOhAMMADI f.MESKINI-VIShKAEE Department of Soil Science Faculty of Agriculture University of Zanjan

Soil moisture characteristic curve （SMC） is a fundamental soil property and its direct measurement is tedious and time consuming. Therefore, various indirect methods have been developed to predict SMC from particle-size distribution （PSD）. however, the majority of these methods often yield intermittent SMC data because they involve estimating individual SMC points. The objectives of this study were 1） to develop a procedure to predict continuous SMC from a limited number of experimental PSD data points and 2） to evaluate model predictions through comparisons with measured values. In this study, an approach that allowed predicting SMC from the knowledge of PSD, parameterized by means of the closed-form van Genuchten model （VG）, was used. Through using Mohammadi and Vanclooster （MV） model, the parameters obtained from fitting of VG to PSD data were applied to predict SMC curves. Since the residual water content （Or） could not be obtained through.f.tting of VG-MV integrated model to PSD data, we also examined and compared four different methods estimating 0r. Results showed that the proposed equation （MV-VG integrated model） provided an excellent fit to all the PSD data and the model could adequately predict SMC as measured in forty-two soils sampled from different regions of Iran. for all soils, the method in which Or Was obtained through parameter optimization procedure provided the best overall predictions of SMC. The two methods estimating Or with Campbell and Shiozawa （CS） model resulted in less accuracy than the optimization procedure. furthermore, the proposed model underestimated the moisture content in the dry range of SMC when the value of 0r was assumed to equal zero. 0r could be attributed to the incomplete desorption of water coated on soil particles and the accurate estimation of 0r was critical in prediction of SMC, especially for fine-textured soils at high suction heads. It could be concluded that the advantages of our approach were the continuity, rob

关键词： fine-textured soils modeling residual water content soil hydraulic properties van Genuchten model

Detailed Description of Mixed Symmetry States in ^94Mo Using Interacting Boson Model

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Communications in Theoretical Physics 2002年第6期37卷 699-705页

作者： f.h.Al－Khudair LONGGui－Lu DepartmentofPhysics TsinghuaUniversityBeijing100084China

We have investigated the low-lying collective states and electromagnetic transitions in 94Mo within the framework of the interacting boson model. The influence of model parameters on the energy levels and electromagnetic properties has been investigated. The analysis of the obtained results and the parameter values predict that the 23+state is the lowest mixed symmetry state with pure f = fmax - 1 in this nucleus. The calculated results predicate that the 25+ (two-Q-phonon) mixed symmetry state is closed to the J = 2+ at 2.870 MeV in the experimental data, and the 2.965 MeV state is the lowest mixed symmetry with J = 3+.

关键词：核物理 ^94Mo混合对称态相互作用玻色子模型

DYNAMIC COMPACTION Of PURE COPPER POWDER USING PULSED MAGNETIC fORCE

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 277-283页

作者： h.P. Yu C.f. Li National Key Laboratory for Precision hot Processing of Metals Harbin Institute of Technology Harbin 150001 China

The compaction of pure Cu powder was carried out through a series of experiments using dynamic magnetic pulse compaction, and the effects of process parameters, such as discharge energy and compacting direction, on the homogeneity and the compaction density of compacted specimens were presented and discussed. The results indicated that the compaction density of specimens increased with the augment of discharge voltage and time. During unidirectional compaction, there was a density gradient along the loading direction in the compacted specimen, and the minimum compaction density was localized to the center of the bottom of the specimen. The larger the aspect ratio of a powder body, the higher the compaction density of the compacted specimen. And high conductivity drivers were beneficial to the increase of the compaction density. The iterative and the double direction compaction were efficient means to manufacture the homogeneous and high-density powder parts.

关键词： magnetic pulse compaction copper powder compaction density electromagnetic forming

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化学反应器设计

化学反应器设计

Ab-Initio Study of Cobalt Impurity Effects on Phonon Spectra, Mechanical and Thermal Properties of Single Wall Carbon Nanotube （5,0）

作者： (美)h.f.·雷斯(h.f. Rase)

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Chinese Physics Letters 2014年第4期31卷 110-113页

作者： h. Tashakori B. Khoshnevisan f. Kanjouri faculty of Physics University of Kashan Kashan Iran faculty of Physics Kharazmi University Karaj Iran

We use density functional perturbation theory based on the pseudo-potential to calculate the phonon spectrum, phonon density of states, specific heat capacity and mechanical properties of pristine and cobalt doped （5,0） single wall carbon nanotube （CNT）. In the calculations, we consider one Co atom in the center of the unit cell of the tube and it is shown that the pristine （5~0） CNT is nonmagnetic while the Co-doped tube becomes magnetic. Young＇s modulus for both systems is about 1 TPa （＇after Co-doping it goes slightly higher） and the Poisson ratio for the pristine tube becomes quite a bit larger than the doped one. On the other hand, the calculated value of radial breath mode for the pristine CNT is in good agreement with the experimental reports while after Co-doping it is increased. In addition, heat capacity of the doped CNT is reduced, which leads to some important empirical applications.

关键词： ChEMICAL vapor deposition DENSITY functional theory PERTURBATION (Mathematics) CARBON nanotubes POISSON'S ratio

A new image watermarking framework based on levels-directions decomposition in contourlet representation

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Journal of Central South University 2017年第3期24卷 521-532页

作者： M.f.Kazemi M.A.Pourmina A.h.Mazinan Department of Electrical and Computer Engineering Science and Research BranchIslamic Azad University(IAU)TehranIran Department of Control Engineering Faculty of Electrical EngineeringSouth Tehran BranchIslamic Azad University(IAU)TehranIran

With the development of digital information technologies,robust watermarking framework is taken into real consideration as a challenging issue in the area of image processing,due to the large applicabilities and its utilities in a number of academic and real *** are a wide range of solutions to provide image watermarking frameworks,while each one of them is attempted to address an efficient and applicable *** reality,the traditional techniques do not have sufficient merit to realize an accurate *** to the fact that the main idea behind the approach is organized based on contourlet representation,the only state-of-the-art materials that are investigated along with an integration of the aforementioned contourlet representation in line with watermarking framework are concentrated to be able to propose the novel and skilled *** a word,the main process of the proposed robust watermarking framework is organized to deal with both new embedding and de-embedding processes in the area of contourlet transform to generate watermarked image and the corresponding extracted logo image with high *** fact,the motivation of the approach is that the suggested complexity can be of novelty,which consists of the contourlet representation,the embedding and the corresponding de-embedding modules and the performance monitoring including an analysis of the watermarked image as well as the extracted logo *** is also a scrambling module that is working in association with levels-directions decomposition in contourlet embedding mechanism,while a decision maker system is designed to deal with the appropriate number of sub-bands to be embedded in the presence of a series of simulated *** required performance is tangibly considered through an integration of the peak signal-to-noise ratio and the structural similarity indices that are related to watermarked *** the bit error rate and the normal correlation are considered that are

关键词： contourlet based watermarking framework levels-directions decomposition embedding process de-embedding process peak signal-to-noise ratio structural similarity indices normal correlation bit error rate

Level-direction decomposition analysis with a focus on image watermarking framework

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frontiers of Information Technology & Electronic Engineering 2016年第11期17卷 1199-1217页

作者： M.f.KAZEMI M.A.POURMINA A.h.MAZINAN Department of Electrical and Computer Engineering Science and Research Branch Islamic Azad University Department of Control Engineering Faculty of Electrical Engineering South Tehran Branch Islamic Azad University

This research addresses the new level-direction decomposition in the area of image watermarking as the further development of investigations. The main process of realizing a watermarking framework is to generate a watermarked image with a focus on contourlet embedding representation. The approach performance is evaluated through several indices including the peak signal-to-noise ratio and structural similarity, whereby a set of attacks are carried out using a module of simulated attacks. The obtained information is analyzed through a set of images, using different color models, to enable the calculation of normal correlation. The module of the inverse of contourlet embedding representation is correspondingly employed to obtain the present watermarked image, as long as a number of original images are applied to a scrambling module, to represent the information in disorder. This allows us to evaluate the performance of the proposed approach by analyzing a complicated system, where a decision making system is designed to find the best level and the corresponding direction regarding contourlet embedding representation. The results are illustrated in appropriate level-direction decomposition. The key contribution lies in using a new integration of a set of subsystems, employed based upon the novel mechanism in contourlet embedding representation, in association with the decision making system. The presented approach is efficient compared with state-of-the-art approaches, under a number of serious attacks. A number of benchmarks are obtained and considered along with the proposed framework outcomes. The results support our ideas.

关键词： Level-direction decomposition analysis Watermarking framework Contourlet embedding representation Scrambling module Simulated attacks