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A new method for separating complex touching equiaxed and lamellar alpha phases in microstructure of titanium alloy
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作者 吉喆 杨合 +1 位作者 李宏伟 樊晓光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2265-2269,共5页
A new method for separating complex touching equiaxed and lamellar alpha phases in the optical micrograph of titanium alloy was proposed for quantitative characterization. This new method involves three steps. First, ... A new method for separating complex touching equiaxed and lamellar alpha phases in the optical micrograph of titanium alloy was proposed for quantitative characterization. This new method involves three steps. First, concave points of the microstructural feature are identified with a threshold of the concaveness of the comer points which are extracted from the binarized image. Secondly, concave points pairs are selected from the concave points group established by means of marker circle or distance. Third, whether a candidate separation line which connects two concave points within a pair can be accepted or not is determined by the proposed four rules. The obtained results show that this method is effective on separating complex touching microstructural features. 展开更多
关键词 titanium alloy microstructural feature separation method
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On the feasibility of variable separation method based on Hamiltonian system for plane magnetoelectroelastic solids 被引量:5
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作者 侯国林 阿拉坦仓 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2753-2758,共6页
The eigenvalue problem of an infinite-dimensional Hamiltonian operator appearing in the isotropic plane magnetoelectroelastic solids is studied. First, all the eigenvalues and their eigenfunctions in a rectangular dom... The eigenvalue problem of an infinite-dimensional Hamiltonian operator appearing in the isotropic plane magnetoelectroelastic solids is studied. First, all the eigenvalues and their eigenfunctions in a rectangular domain are solved directly. Then the completeness of the eigenfunction system is proved, which offers a theoretic guarantee of the feasibility of variable separation method based on a Hamiltonian system for isotropic plane magnetoelectroelastic solids. Finally, the general solution for the equation in the rectangular domain is obtained by using the symplectic Fourier expansion method. 展开更多
关键词 magnetoelectroelastic solid variable separation method COMPLETENESS general solution
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Solving mKdV-sinh-Gordon equation by a modified variable separated ordinary differential equation method 被引量:4
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作者 谢元喜 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第12期5123-5132,共10页
By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ODE method is developed for solving the mKdV-sinh-Gordon equation. As a result, many explicit and exact sol... By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ODE method is developed for solving the mKdV-sinh-Gordon equation. As a result, many explicit and exact solutions including some new formal solutions are successfully picked up for the mKdV-sinh-Gordon equation by this approach. 展开更多
关键词 modified variable separated ODE method mKdV-sinh-Gordon equation explicit andexact solution
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Extended Group Foliation Method and Functional Separation of Variables to Nonlinear Wave Equations 被引量:9
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作者 QU Chang-Zheng ZHANG Shun-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期577-582,共6页
Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to n... Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to nonlinear wave equations with variable speed and external force. A complete classification for the wave equation which admits functional separable solutions is presented. Some known results can be recovered by this approach. 展开更多
关键词 symmetry group group foliation method nonlinear wave equation functional separation of variables
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Functional Separable Solutions to Nonlinear Diffusion Equations by Group Foliation Method 被引量:5
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作者 HU Jia-Yi QU Chang-Zheng YIN Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期193-199,共7页
We consider the functional separation of variables to the nonlinear diffusion equation with source and convection term: ut = (A(x)D(u)ux)x + B(x)Q(u), Ax ≠ 0. The functional separation of variables to thi... We consider the functional separation of variables to the nonlinear diffusion equation with source and convection term: ut = (A(x)D(u)ux)x + B(x)Q(u), Ax ≠ 0. The functional separation of variables to this equation is studied by using the group foliation method. A classification is carried out for the equations which admit the function separable solutions. As a consequence, some solutions to the resulting equations are obtained. 展开更多
关键词 group foliation method functional separation of variable nonlinear diffusion equation symmetry group
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Neutron-gamma discrimination method based on blind source separation and machine learning 被引量:5
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作者 Hanan Arahmane El-Mehdi Hamzaoui +1 位作者 Yann Ben Maissa Rajaa Cherkaoui El Moursli 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第2期70-80,共11页
The discrimination of neutrons from gamma rays in a mixed radiation field is crucial in neutron detection tasks.Several approaches have been proposed to enhance the performance and accuracy of neutron-gamma discrimina... The discrimination of neutrons from gamma rays in a mixed radiation field is crucial in neutron detection tasks.Several approaches have been proposed to enhance the performance and accuracy of neutron-gamma discrimination.However,their performances are often associated with certain factors,such as experimental requirements and resulting mixed signals.The main purpose of this study is to achieve fast and accurate neutron-gamma discrimination without a priori information on the signal to be analyzed,as well as the experimental setup.Here,a novel method is proposed based on two concepts.The first method exploits the power of nonnegative tensor factorization(NTF)as a blind source separation method to extract the original components from the mixture signals recorded at the output of the stilbene scintillator detector.The second one is based on the principles of support vector machine(SVM)to identify and discriminate these components.In addition to these two main methods,we adopted the Mexican-hat function as a continuous wavelet transform to characterize the components extracted using the NTF model.The resulting scalograms are processed as colored images,which are segmented into two distinct classes using the Otsu thresholding method to extract the features of interest of the neutrons and gamma-ray components from the background noise.We subsequently used principal component analysis to select the most significant of these features wich are used in the training and testing datasets for SVM.Bias-variance analysis is used to optimize the SVM model by finding the optimal level of model complexity with the highest possible generalization performance.In this framework,the obtained results have verified a suitable bias–variance trade-off value.We achieved an operational SVM prediction model for neutron-gamma classification with a high true-positive rate.The accuracy and performance of the SVM based on the NTF was evaluated and validated by comparing it to the charge comparison method via figure of merit.The results indicate that the proposed approach has a superior discrimination quality(figure of merit of 2.20). 展开更多
关键词 Blind source separation Nonnegative tensor factorization(NTF) Support vector machines(SVM) Continuous wavelets transform(CWT) Otsu thresholding method
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Preparation of Microcapsules with Liquid Droplet Coalescence Method Followed by Phase Separation 被引量:3
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作者 Yasushi Yokoyama Kiyomi Fuchigami +1 位作者 Yoshinari Taguchi Masato Tanaka 《Journal of Encapsulation and Adsorption Sciences》 2013年第3期93-97,共5页
Novel preparation method of microencapsules was developed on the basis of the liquid coalescence method followed by phase separation. Oil droplets of limonene dissolving expanded polystyrene as a shell material were f... Novel preparation method of microencapsules was developed on the basis of the liquid coalescence method followed by phase separation. Oil droplets of limonene dissolving expanded polystyrene as a shell material were forced to collide and coalesce with the Isopar oil droplets of core material in the continuous wates phase. When two kinds of oil droplets are collided and coalesced with each other, expanded polystyrene dissolved in the limonene oil may be phase-separated in the oil droplets newly formed to form the microcapsule shell, because the Isopar oil was a poor solvent for expanded polystyrene but a good solvent for the limonene oil. In the experiment, the diameter (or number) of limonene oil droplets dissolving expanded polystyrene was mainly changed, because the coalescence frequency between the droplets is strongly dependent on the number of droplets. Favorable core shell types of microcapsules with the shell thickness from 1.0 to 5.0 μm were able to be prepared under all the experimental conditions adopted here. 展开更多
关键词 Core Shell MICROCAPSULE Liquid DROPLET COALESCENCE method Phase separation LIMONENE Oil LIQUID-LIQUID Dispersion
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A Privilege Separation Method for Security Commercial Transactions 被引量:1
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作者 Chen Yasha Hu Jun +1 位作者 Sun Yu Gai Xinmao 《China Communications》 SCIE CSCD 2010年第6期94-99,共6页
Privilege user is needed to manage the commercial transactions, but a super-administrator may have monopolize power and cause serious security problem. Relied on trusted computing technology, a privilege separation me... Privilege user is needed to manage the commercial transactions, but a super-administrator may have monopolize power and cause serious security problem. Relied on trusted computing technology, a privilege separation method is proposed to satisfy the security management requirement for information systems. It authorizes the system privilege to three different managers, and none of it can be interfered by others. Process algebra Communication Sequential Processes is used to model the three powers mechanism, and safety effect is analyzed and compared. 展开更多
关键词 privilege separation fraud management security commercial transactions formal method
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Solving (2+1)-dimensional sine-Poisson equation by a modified variable separated ordinary differential equation method 被引量:1
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作者 苏卡林 谢元喜 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期40-48,共9页
By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ordinary differential equation method is presented for solving the (2 + 1)-dimensional sine-Poisson equa... By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ordinary differential equation method is presented for solving the (2 + 1)-dimensional sine-Poisson equation. As a result, many explicit and exact solutions of the (2 + 1)-dimensional sine-Poisson equation are derived in a simple manner by this technique. 展开更多
关键词 modified variable separated ODE method (2 1)-dimensional sine-Poisson equation explicit and exact solution
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A SPECIAL METHOD OF FOURIER SERIES WHICH IS EQUAL TO THE METHOD OF SEPARATION OF VARIABLES ON BOUNDARY VALUE PROBLEM
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作者 Yan Xianggan Wu Jike, Department of Mechanics, Peking Unirersity, Bejing 100871. China 《Acta Mechanica Solida Sinica》 SCIE EI 1997年第3期255-261,共7页
By the separation of singularity, a special Fourier series solution of the boundary value problem for plane is obtained, which can satisfy all boundary conditions and converges rapidly. II is proved that the solution ... By the separation of singularity, a special Fourier series solution of the boundary value problem for plane is obtained, which can satisfy all boundary conditions and converges rapidly. II is proved that the solution is equal to the result of separation of variables. As a result, the non-linear characteristic equations resulting from the method of separation of variables are transformed into polynomial equations that can provide a foundation for approximate computation and asymptotic analysis. 展开更多
关键词 separation of singularity series resolution method of separation of variables boundary value problem characteristic equation
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P-and S-wavefield simulations using both the firstand second-order separated wave equations through a high-order staggered grid finite-difference method
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作者 Chao-ying Bai Xin Wang Cai-xia Wang 《Earthquake Science》 2013年第2期83-98,共16页
In seismic exploration, it is common practice to separate the P-wavefield from the S-wavefield by the elastic wavefield decomposition technique, for imaging purposes. However, it is sometimes difficult to achieve this... In seismic exploration, it is common practice to separate the P-wavefield from the S-wavefield by the elastic wavefield decomposition technique, for imaging purposes. However, it is sometimes difficult to achieve this, especially when the velocity field is complex. A useful approach in multi-component analysis and modeling is to directly solve the elastic wave equations for the pure P- or S-wavefields, referred as the separate elastic wave equa- tions. In this study, we compare two kinds of such wave equations: the first-order (velocity-stress) and the second- order (displacement-stress) separate elastic wave equa- tions, with the first-order (velocity-stress) and the second- order (displacement-stress) full (or mixed) elastic wave equations using a high-order staggered grid finite-differ- ence method. Comparisons are given of wavefield snap- shots, common-source gather seismic sections, and individual synthetic seismogram. The simulation tests show that equivalent results can be obtained, regardless of whether the first-order or second-order separate elastic wave equations are used for obtaining the pure P- or S-wavefield. The stacked pure P- and S-wavefields are equal to the mixed wave fields calculated using the corre- sponding first-order or second-order full elastic wave equations. These mixed equations are computationallyslightly less expensive than solving the separate equations. The attraction of the separate equations is that they achieve separated P- and S-wavefields which can be used to test the efficacy of wave decomposition procedures in multi-com- ponent processing. The second-order separate elastic wave equations are a good choice because they offer information on the pure P-wave or S-wave displacements. 展开更多
关键词 Finite-difference method Staggeredgrid First-order separate elastic wave equation Second-order separate elastic wave equation Multiple arrival tracking
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Some discussions about method for solving the variable separating nonlinear models
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作者 阮航宇 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期17-24,共8页
Through analysing the exact solution of some nonlinear models, the role of the variable separating method in solving nonlinear equations is discussed. We find that rich solution structures of some special fields of th... Through analysing the exact solution of some nonlinear models, the role of the variable separating method in solving nonlinear equations is discussed. We find that rich solution structures of some special fields of these equations come from the nonzero seed solution. However, these nonzero seed solutions is likely to result in the divergent phenomena for the other field component of the same equation. The convergence and the signification of all field components should be discussed when someone solves the nonlinear equation using the variable separating method. 展开更多
关键词 variable separating method nonzero seed solution nonlinear equation
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Application of Multi-objective Optimization Method to Extracton Separtion Process
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作者 吴华武 来月英 《Rare Metals》 SCIE EI CAS CSCD 1995年第1期8-12,共5页
A multi-objective decision procedure was proposed to select the optimal precase parameters of extractionseporating zirconium and hafnium from sulphuric acid solution with Alamine-336 as an extractant in this pa-per.Ad... A multi-objective decision procedure was proposed to select the optimal precase parameters of extractionseporating zirconium and hafnium from sulphuric acid solution with Alamine-336 as an extractant in this pa-per.Adaptive Random Search(ARS) algorithm was adopted for optimizing calculation. The results obtainedshow that the multi-objective decision method is much better than sangle-objecive decision method. 展开更多
关键词 Extractive separation Zirconium and hafnium Multi-objectiveoptimization method
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Separation Method in the Problem of a Beam-Plasma Interaction in a Cylindrical Warm Plasma Waveguide
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作者 Khaled H. El-Shorbagy Abdelrahman S. Al-Fhaid Mohamed A. Al-Ghamdi 《Journal of Modern Physics》 2011年第10期1104-1108,共5页
The stabilization effect of a strong HF electric field on beam-plasma instability in a cylindrical warm plasma waveguide is discussed. A mathematical technique “separation method” applied to the two-fluid plasma mod... The stabilization effect of a strong HF electric field on beam-plasma instability in a cylindrical warm plasma waveguide is discussed. A mathematical technique “separation method” applied to the two-fluid plasma model to separate the equations, which describe the system, into two parts, temporal and space parts. Plasma electrons are considered to have a thermal velocity. It is shown that a HF electric field has no essential influence on dispersion characteristics of unstable surface waves excited in a warm plasma waveguide by a low-density electron beam. The region of instability only slightly narrowing and the growth rate decreases by a small parameter and this result has been reduced compared to cold plasma. Also, it is found that the plasma electrons have not affected the solution of the space part of the problem. 展开更多
关键词 separATION method Beam-Plasma Interaction WARM PLASMA WAVEGUIDE
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A Novel Method for Separation of Tungsten and Molybdenum
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作者 Jiang Anren Pang Zhen Jiang Weizhong Department of Chemistry,Fudan University,Shanghai 《Rare Metals》 SCIE EI CAS CSCD 1989年第3期63-65,共3页
Research on the separation of tungstenand molybdenum is of importance as it is a ba-sic problem in the metallurgy and industry oftungsten.Traditional methods for the separa-tion include precipitation with sulfides and... Research on the separation of tungstenand molybdenum is of importance as it is a ba-sic problem in the metallurgy and industry oftungsten.Traditional methods for the separa-tion include precipitation with sulfides andsolvent extraction.There are,however,certaindisadvantages for these methods.A novelmethod was developed based on another 展开更多
关键词 A Novel method for separation of Tungsten and Molybdenum
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Simplified quantitative analysis method and its application in the insitu synthesized copper-based azide chips
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作者 Jie Ren Yunfeng Li +3 位作者 Mingyu Li Xingyu Wu Jiabao Wang Qingxuan Zeng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期309-316,共8页
Copper-based azide(Cu(N_(3))2 or CuN_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent years.However,the advantages of in-situ ... Copper-based azide(Cu(N_(3))2 or CuN_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent years.However,the advantages of in-situ synthesis method,including small size and low dosage,bring about difficulties in quantitative analysis and differences in ignition capabilities of CA chips.The aim of present work is to develop a simplified quantitative analysis method for accurate and safe analysis of components in CA chips to evaluate and investigate the corresponding ignition ability.In this work,Cu(N_(3))2 and CuN_(3)components in CA chips were separated through dissolution and distillation by utilizing the difference in solubility and corresponding content was obtained by measuring N_(3)-concentration through spectrophotometry.The spectrophotometry method was optimized by studying influencing factors and the recovery rate of different separation methods was studied,ensuring the accuracy and reproducibility of test results.The optimized method is linear in range from 1.0-25.0 mg/L,with a correlation coefficient R^(2)=0.9998,which meets the requirements of CA chips with a milligram-level content test.Compared with the existing ICP method,component analysis results of CA chips obtained by spectrophotometry are closer to real component content in samples and have satisfactory accuracy.Moreover,as its application in miniaturized explosive systems,the ignition ability of CA chips with different component contents for direct ink writing CL-20 and the corresponding mechanism was studied.This study provided a basis and idea for the design and performance evaluation of CA chips in miniaturized explosive systems. 展开更多
关键词 Copper-based azide chips SPECTROPHOTOMETRY separation method Quantitative analysis Ignition ability
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Numerical Simulation Study of Oil-Water Emulsion Separation in an Ultrasonic Field:Effect of Coupling between Acoustic and Flow Field Parameters
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作者 Wang Heping Lin Yinchao +2 位作者 Li Yanggui Zhang Xiaohang Wu Yi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期116-125,共10页
In this study,the separation and coalescence of oil-in-water emulsions are explored in an ultrasonic field using the lattice Boltzmann method.By simulating the propagation of ultrasonic waves,this study focuses on exa... In this study,the separation and coalescence of oil-in-water emulsions are explored in an ultrasonic field using the lattice Boltzmann method.By simulating the propagation of ultrasonic waves,this study focuses on examining the effects of acoustic wave frequency,the ratio of oil to water components,and the aspect ratio of the boundary on the emulsification and separation processes of oil-water mixtures.The following conclusions are drawn.①Frequency affects the speed of oil droplet separation,leading to an increase in droplet size over time.Larger droplets are found near the source,while smaller droplets are distributed throughout the wave web.②As the boundary aspect ratio increases,the emulsification efficiency of the droplets weakens,and the system takes longer to stabilize.③Emulsions with a higher component of oil can better resist acoustic waves.④At the same acoustic frequency,longer wavelength ultrasonic fields promote the formation of uniformly distributed,smaller oil droplets,which is beneficial to the storage of emulsions.These numerical simulation results offer insights for optimizing conditions for oil-in-water separation and serve as a numerical reference for the study of oil-in-water emulsion separation in ultrasonic environments. 展开更多
关键词 lattice Boltzmann method phase separation ultrasound field
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A New Algorithm of Roundness Error Separation Technique of Three-point Method
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作者 雷贤卿 李济顺 +3 位作者 薛玉君 马伟 崔凤奎 胡东方 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第2期141-145,共5页
Through the analysis of roundness error separation technique of three-point method and based on the invariability and periodicity of the geometrical characteristic of measured round contour, a new matrix algorithm, wh... Through the analysis of roundness error separation technique of three-point method and based on the invariability and periodicity of the geometrical characteristic of measured round contour, a new matrix algorithm, which can be used to solve directly the roundness of the measured round contour without Fourier transform, is presented. On the basis of the research and analysis of the rotation error movement which is separated by using the three-point method, a mathematical equation is derived, which can be used to separate the eccentric motion of least square center of measured round contour and the pure rotation motion error of spindle in rotation motion. The correctness of this method is validated by means of simulation. 展开更多
关键词 信息加工 三点方法 矩阵 偏心运动
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Estimation of non-point source pollution loads with flux method in Danjiangkou Reservoir area,China 被引量:8
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作者 Xiao-kang Xin Wei Yin Ke-feng Li 《Water Science and Engineering》 EI CAS CSCD 2017年第2期134-142,共9页
The estimation of non-point source pollution loads into the Danjiangkou Reservoir is highly significant to environmental protection in the watershed. In order to overcome the drawbacks of traditional watershed numeric... The estimation of non-point source pollution loads into the Danjiangkou Reservoir is highly significant to environmental protection in the watershed. In order to overcome the drawbacks of traditional watershed numerical models, a base flow separation method was established coupled with a digital filtering method and a flux method. The digital filtering method has been used to separate the base flows of the Hanjiang,Tianhe, Duhe, Danjiang, Laoguan, and Qihe rivers. Based on daily discharge, base flow, and pollutant concentration data, the flux method was used to calculate the point source pollution load and non-point source pollution load. The results show that:(1) In the year 2013, the total inflow of the six rivers mentioned above accounted for 95.9% of the total inflow to the Danjiangkou Reservoir. The total pollution loads of chemical oxygen demand(CODMn) and total phosphorus(TP) from the six rivers were 58.20 103 t and 1.863 10~3 t, respectively, and the non-point source pollution loads were 39.82 10~3 t and 1.544 10~3 t, respectively, indicating that the non-point source pollution is a major factor(with a contribution rate of 68.4% for CODMnand 82.9% for TP).(2) The Hanjiang River is the most significant contributor of pollution loads to the Danjiangkou Reservoir, and its CODMnand TP contribution rates reached 79.3% and 83.2%, respectively. The Duhe River took the second place.(3) Non-point source pollution mainly occurred in the wet season in 2013, accounting for 80.8% and 90.9% of the total pollution loads of CODMnand TP, respectively. It is concluded that the emphasis of pollution control should be placed on non-point source pollution. 展开更多
关键词 Danjiangkou RESERVOIR Non-point source POLLUTION Base flow separation Digital FILTERING method (DFM) FLUX method
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Numerical simulation of unsteady interaction of centrifugal impeller with its diffuser using Lagrangian discrete vortex method 被引量:5
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作者 BaoshanZhu KyojiKamemoto 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第1期40-46,共7页
In this study, an advanced Lagrangian vortex- boundary element method is applied to simulate the unsteady impeller-diffuser interactions in a diffuser pump not only for design but also for off-design considerations. I... In this study, an advanced Lagrangian vortex- boundary element method is applied to simulate the unsteady impeller-diffuser interactions in a diffuser pump not only for design but also for off-design considerations. In velocity calculations based on the Biot-Savart law we do not have to grid large portions of the flow field and the calculation points are concentrated in the regions where vorticity is present. Lagrangian representation of the evolving vorticity field is well suited to moving boundaries. An integral pressure equation shows that the pressure distribution can be estimated directly from the instantaneous velocity and vorticity field. The numerical results are compared with the experimental data and the comparisons show that the method used in this study can provide us insight into the complicated unsteady impeller-diffuser interaction phenomena in a diffuser pump. 展开更多
关键词 Rotor-stator interaction Unsteady flow Vortex method Flow separation
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