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Antibiotic-Resistant Bacterial Group in Field Soil Evaluated by a Newly Developed Method Based on Restriction Fragment Length Polymorphism Analysis 被引量:1
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作者 Katsuji Watanabe Naoto Horinishi Kunimasa Matumoto 《Advances in Microbiology》 2015年第12期807-816,共10页
Spreading of antibiotic resistant bacteria into environment is becoming a major public health problem, implicating affair of the indirect transmission of antibiotic resistant bacteria to human through drinking water, ... Spreading of antibiotic resistant bacteria into environment is becoming a major public health problem, implicating affair of the indirect transmission of antibiotic resistant bacteria to human through drinking water, or vegetables, or daily products. Until now, the risk of nosocomial infection of antibiotic resistant bacteria has mainly been evaluated using clinical isolates by phenotypic method. To evaluate a risk of community-acquired infection of antibiotic resistant bacteria, a new method has been developed based on PCR-RFLP without isolation. By comparing restriction fragment lengths of the 16S rDNA gene from bacterial mixture grown under antibiotic treatment to those simulated from the DNA sequence, bacterial taxonomies were elucidated using the method of Okuda and Watanabe [1] [2]. In this study, taxonomies of polymyxin B resistant bacteria group in field soils, paddy field with organic manure and upland field without organic manure were estimated without isolation. In the both field soils, the major bacteria grown under the antibiotic were B. cereus group, which had natural resistance to this antibiotic. In field applied with organic manure, Prevotella spp., and the other Cytophagales, which were suggested to be of feces origin and to acquire resistance to the antibiotic, were detected. When numbers of each bacterial group were roughly estimated by the most probable number method, B. cereus group was enumerated to be 3.30 × 106 MPN/g dry soil in paddy field soil and 1.32 × 106 MPN/g dry soil in upland filed. Prevotella spp. and the other Cytophagales in paddy field were enumerated to be 1.31 × 106 MPN, and 1.07 × 106 MPN·g-1 dry soil. 展开更多
关键词 POLYMYXIN B Resistant Bacteria Field Soil Microchip ELECTROPHORESIS Multiple Enzyme RESTRICTION FRAGMENT Length Polymorphism analysis the Most PROBABLE Number method
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A Comparison of Weighing Methods Prior to Fusion Preparing Iron Samples for XRF Analysis
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作者 Louis Lefrancois Perreault Mathieu Bouchard 《Journal of Chemistry and Chemical Engineering》 2019年第2期93-100,共8页
Sample preparation by fusion for XRF analysis is all about knowing the exact weights of the sample and the flux (sample-to-flux ratio). The whole analytical chain, including the weighing step in sample preparation pri... Sample preparation by fusion for XRF analysis is all about knowing the exact weights of the sample and the flux (sample-to-flux ratio). The whole analytical chain, including the weighing step in sample preparation prior to fusion, is of crucial importance to get precise and accurate x-ray fluorescence (XRF) results. Consequently, the weighing method will affect the quality of the analytical results given by the spectrometer. In this study, the effects of different weighing methods on the precision (RSD) of the obtained XRF results are compared to determine the best weighing method for sample preparation by fusion in terms of comparable precisions in the XRF results. 展开更多
关键词 WEIGHING method SAMPLE preparation by FUSION tolerance accepted XRF analysis precision accuracy ANALYTICAL method sample-to-flux ratio ANALYTICAL results AUTOMATIC dispensing balance AUTOMATIC WEIGHING instrument
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Bacterial Groups Concerned with Maturing Process in Manure Production Analyzed by a Method Based on Restriction Fragment Length Polymorphism Analysis
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作者 Katsuji Watanabe Naoto Horinishi +2 位作者 Kunimasa Matumoto Akihiro Tanaka Kenichi Yakushido 《Advances in Microbiology》 2015年第13期832-841,共10页
Composting is a biological aerobic decomposition process consisted from different phases. Although the Japanese Standards for manure recommended that it took at least 6 months to complete the maturing phase, there was... Composting is a biological aerobic decomposition process consisted from different phases. Although the Japanese Standards for manure recommended that it took at least 6 months to complete the maturing phase, there was no reliable ground. In order to find out shortening method of the maturing phase, the microorganisms concerned with a progress of the maturing was determined by using the most probable number method (MPN) and PCR-RFLP of the 16S rDNA, which was found effective to provide numbers and taxonomy of polymyxin B resistant bacterial groups in the former paper [1]. Compared to the numbers after thermophilic phase, those of Actinobacteria, δ-proteobacteria, and the other gram negative bacteria increased to 50 times, 20 times, and 105 times, respectively, after maturing phase, while those of Bacillus spp., and α and β-proteobacteria decreased to 1/10, and 1/105 after maturing phase. Numbers of the other Fumicutes, and γ-proteobacteria remained in the same revel. Actinobacteria, δ-proteobacteria, and the other gram negative bacteria might be concerned with a progress of the maturing phase, because these bacterial groups were detected and enumerated due to their proliferation ability. Although number of Acitinobacteria might be underestimated because of a PCR bias, the method was found effective for the purpose to monitor bacteria actively proliferated in culture medium. 展开更多
关键词 Maturing Phase MANURE PRODUCTION Microchip ELECTROPHORESIS Multiple Enzyme RESTRICTION Fragment Length Polymorphism analysis The Most PROBABLE Number method
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Study of inter-well interference in shale gas reservoirs by a robust production data analysis method based on deconvolution
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作者 Wen-Chao Liu Cheng-Cheng Qiao +5 位作者 Ping Wang Wen-Song Huang Xiang-Wen Kong Yu-Ping Sun He-Dong Sun Yue-Peng Jia 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2502-2519,共18页
In order to overcome the defects that the analysis of multi-well typical curves of shale gas reservoirs is rarely applied to engineering,this study proposes a robust production data analysis method based on deconvolut... In order to overcome the defects that the analysis of multi-well typical curves of shale gas reservoirs is rarely applied to engineering,this study proposes a robust production data analysis method based on deconvolution,which is used for multi-well inter-well interference research.In this study,a multi-well conceptual trilinear seepage model for multi-stage fractured horizontal wells was established,and its Laplace solutions under two different outer boundary conditions were obtained.Then,an improved pressure deconvolution algorithm was used to normalize the scattered production data.Furthermore,the typical curve fitting was carried out using the production data and the seepage model solution.Finally,some reservoir parameters and fracturing parameters were interpreted,and the intensity of inter-well interference was compared.The effectiveness of the method was verified by analyzing the production dynamic data of six shale gas wells in Duvernay area.The results showed that the fitting effect of typical curves was greatly improved due to the mutual restriction between deconvolution calculation parameter debugging and seepage model parameter debugging.Besides,by using the morphological characteristics of the log-log typical curves and the time corresponding to the intersection point of the log-log typical curves of two models under different outer boundary conditions,the strength of the interference between wells on the same well platform was well judged.This work can provide a reference for the optimization of well spacing and hydraulic fracturing measures for shale gas wells. 展开更多
关键词 Shale gas Inter-well interference DECONVOLUTION Production data analysis Typical curves Multi-stage fractured horizontal well
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Analytical Solution for the Time-Dependent Emden-Fowler Type of Equations by Homotopy Analysis Method with Genetic Algorithm
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作者 Waleed Al-Hayani Laheeb Alzubaidy Ahmed Entesar 《Applied Mathematics》 2017年第5期693-711,共19页
In this paper, Homotopy Analysis method with Genetic Algorithm is presented and used to obtain an analytical solution for the time-dependent Emden-Fowler type of equations and wave-type equation with singular behavior... In this paper, Homotopy Analysis method with Genetic Algorithm is presented and used to obtain an analytical solution for the time-dependent Emden-Fowler type of equations and wave-type equation with singular behavior at x = 0. The advantage of this single global method employed to present a reliable framework is utilized to overcome the singularity behavior at the point x = 0 for both models. The method is demonstrated for a variety of problems in one and higher dimensional spaces where approximate-exact solutions are obtained. The results obtained in all cases show the reliability and the efficiency of this method. 展开更多
关键词 HOMOTOPY analysis method Genetic Algorithm EMDEN-FOWLER EQUATION Wave-Type EQUATION Adomian Polynomials Noise Terms Padé APPROXIMANTS SIMPSON Rule
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Long-term deformation analysis of Shuibuya concrete face rockfill dam based on response surface method and improved genetic algorithm 被引量:12
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作者 Fu-hai Yao Shao-heng Guan +4 位作者 He Yang Yuan Chen Huan-feng Qiu Gang Ma Qi-wen Liu 《Water Science and Engineering》 EI CAS CSCD 2019年第3期196-204,共9页
Due to the size effects of rockfill materials, the settlement difference between numerical simulation and in situ monitoring of rockfill dams is a topic of general concern.The constitutive model parameters obtained fr... Due to the size effects of rockfill materials, the settlement difference between numerical simulation and in situ monitoring of rockfill dams is a topic of general concern.The constitutive model parameters obtained from laboratory triaxial tests often underestimate the deformation of high rockfill dams.Therefore, constitutive model parameters obtained by back analysis were used to calculate and predict the long-term deformation of rockfill dams.Instead of using artificial neural networks (ANNs), the response surface method (RSM) was employed to replace the finite element simulation used in the optimization iteration.Only 27 training samples were required for RSM, improving computational efficiency compared with ANN, which required 300 training samples.RSM can be used to describe the relationship between the constitutive model parameters and dam settlements.The inversion results of the Shuibuya concrete face rockfill dam (CFRD) show that the calculated settlements agree with the measured data, indicating the accuracy and efficiency of RSM. 展开更多
关键词 SHUIBUYA ROCKFILL DAM Parameter BACK analysis Response surface method Duncan EB model TIME-DEPENDENT deformation
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Analysis of Office-Teaching Comprehensive Buildings Using a Modified Seismic Performance Evaluation Method
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作者 Hanbo Zhu Changqing Miao Meiling Zhuang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第3期471-491,共21页
Current building design codes allow the appearance of structural and nonstructural damage under design basis earthquakes.The research regarding probabilistic seismic loss estimation in domestic building structure is u... Current building design codes allow the appearance of structural and nonstructural damage under design basis earthquakes.The research regarding probabilistic seismic loss estimation in domestic building structure is urgent.The evaluation in this paper is based on a 11-story reinforced concrete office building,incremental dynamic analysis(IDA)is conducted in Perform 3D program using models capable to simulate all possible limit states up to collapse.Next,the probability distribution of post-earthquake casualties,rebuild costs repair costs and business downtime loss are calculated in PACT software for the studied building considering the modified component vulnerability groups and population flow models.The evaluation procedure can also shed light on other types of buildings in China.For non-typical functional building structures,this article proposes to build a finite element model of structural components and to classify the vulnerability groups based on the construction drawings,and to supply and improve the vulnerability library of appendages in FEMA P-58 according to the actual situation.In this way,the application scope of building seismic performance evaluation can be expanded. 展开更多
关键词 A MODIFIED SEISMIC capacity ASSESSMENT method frame-shear wall structure incremental dynamic analysis(IDA) SEISMIC performance ASSESSMENT analysis software(PACT)
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Method of Phase Diagrams for the Analysis of Seism-Acoustical Spatial-Time Monitoring Data in Oil Wells
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作者 Olga Hachay Oleg Khachay 《Open Journal of Geology》 2018年第9期874-882,共9页
Experimental and theoretical studies of the mechanisms of vibration stimulation of oil recovery in watered fields lead to the conclusion that resonance oscillations develop in fractured-block formations. These oscilla... Experimental and theoretical studies of the mechanisms of vibration stimulation of oil recovery in watered fields lead to the conclusion that resonance oscillations develop in fractured-block formations. These oscillations, caused by weak but long-lasting and frequency-stable influences, create the conditions for ultrasonic wave’s generation in the layers, which are capable of destroying thickened oil membranes in reservoir cracks. For fractured-porous reservoirs in the process of exploitation by the method of water high-pressure oil displacement, the possibility of intensifying ultrasonic vibrations can have an important technological significance. Even a very weak ultrasound can destroy, over a long period of time, the viscous oil membranes formed in the cracks between the blocks, which can be the reason for lowering the permeability of the layers and increasing the oil recovery. To describe these effects, it is necessary to consider the wave process in a hierarchically blocky environment and theoretically simulate the mechanism of the appearance of self-oscillations under the action of relaxation shear stresses. For the analysis of seism acoustic response in time on fixed intervals along the borehole an algorithm of phase diagrams of the state of many-phase medium is suggested. 展开更多
关键词 Phase DIAGRAMS method of analysis SPACE-TIME Monitoring Data Oil WELLS State of the Two Component MEDIUM
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Analytic Solution for Fluid Flow over an Exponentially Stretching Porous Sheet with Surface Heat Flux in Porous Medium by Means of Homotopy Analysis Method
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作者 Azhar Ali H. Zaman +1 位作者 M. Z. Abidin S. I. A. Shah 《American Journal of Computational Mathematics》 2015年第2期224-238,共15页
In this paper, the analytical solution of a viscous and incompressible fluid towards an exponentially stretching porous sheet with surface heat flux in porous medium, for the boundary layer and heat transfer flow, is ... In this paper, the analytical solution of a viscous and incompressible fluid towards an exponentially stretching porous sheet with surface heat flux in porous medium, for the boundary layer and heat transfer flow, is presented. The equations of continuity, momentum and the energy are transformed into non-linear ordinary differential by using similarity transformation. The solutions of these highly non-linear ordinary differential equations are found analytically by means of Homotopy Analysis Method (HAM). The result obtained by HAM is compared with numerical results presented in the literature. The accuracy of the HAM is indicated by close agreement of the two sets of results. By this method, an expression is obtained which is admissible for all values of effective parameters. This method has the ability to control the convergence of the solution. 展开更多
关键词 EXPONENTIALLY STRETCHING SHEET Suction/Blowing Variable Surface Heat Flux POROUS Medium Analytical Solution HOMOTOPY analysis method
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FURTHER RESEARCH ON THE SPLINE MODEL METHOD OF KED ANALYSIS IN A PLANAR FLEXIBLE LINKAGE
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作者 管伯良 张程 《Journal of China Textile University(English Edition)》 EI CAS 1994年第1期66-74,共9页
This paper relates to the deep research on the Splinc Model Method of KED analysis. With the use of cubic B-splinc function as a link’s transverse deflection interpolation function, the principle of virtual displacem... This paper relates to the deep research on the Splinc Model Method of KED analysis. With the use of cubic B-splinc function as a link’s transverse deflection interpolation function, the principle of virtual displacement is presented as a basic theory for the general formulation of the equations of motion, and thus abandoned the kinematic assumption and the instantaneous structure assumption which arc used in the Spline Model Method. In thc same time, the nonlinear terms sue as coupling terms between thc rigid body motion and elastic deformation arc included. New member’s spline models are established. Mass matrix, Coriolis mass matrix, normal and tangential mass matrix, linear stiffness matrix, nonlinear stiffness matrix and rotation matrix arc derived. The kinematic differential equations of a member and system are deduced in the end. The Newmark direct integration method is used as the solution scheme of the kinematic differential equations to get the periodic response. 展开更多
关键词 link mechanisms SPLINE functions elastic deformation SPLINE MODEL method KED analysis SPLINE model PLANAR flexible linkage.
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Modified slow-fast analysis method for slow-fast dynamical systems with two scales in frequency domain 被引量:2
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作者 Zhengdi Zhang Zhangyao Chen Qinsheng Bi 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第6期358-362,共5页
A modified slow-fast analysis method is presented for the periodically excited non-autonomous dynamical system with an order gap between the exciting frequency and the natural frequency.By regarding the exciting term ... A modified slow-fast analysis method is presented for the periodically excited non-autonomous dynamical system with an order gap between the exciting frequency and the natural frequency.By regarding the exciting term as a slow-varying parameter,a generalized autonomous fast subsystem can be defined,the equilibrium branches as well as the bifurcations of which can be employed to account for the mechanism of the bursting oscillations by combining the transformed phase portrait introduced.As an example,a typical periodically excited Hartley model is used to demonstrate the validness of the method,in which the exciting frequency is far less than the natural frequency.The equilibrium branches and their bifurcations of the fast subsystem with the variation of the slow-varying parameter are presented.Bursting oscillations for two typical cases are considered,which reveals that,fold bifurcation may cause the the trajectory to jump between different equilibrium branches,while Hopf bifurcation may cause the trajectory to oscillate around the stable limit cycle. 展开更多
关键词 TWO scales in frequency domain MODIFIED slow-fast analysis method BURSTING oscillations Bifurcation mechanism
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Optimization of Tribological Performance of Al-6061T6-15% SiCp-15% Al<sub>2</sub>O<sub>3</sub>Hybrid Metal Matrix Composites Using Taguchi Method &Grey Relational Analysis
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作者 Ashok Kr. Mishra Vinod Kumar Rajesh Kr. Srivastava 《Journal of Minerals and Materials Characterization and Engineering》 2014年第4期351-361,共11页
In this investigation, optimization of tribological performance parameters of Al-6061T6 alloy reinforced with SiC (15% by weight) and Al2O3 (15% by weight) particulates having particle size of 37 μm each has been pre... In this investigation, optimization of tribological performance parameters of Al-6061T6 alloy reinforced with SiC (15% by weight) and Al2O3 (15% by weight) particulates having particle size of 37 μm each has been presented. The wear and frictional properties of the hybrid metal matrix composites have been studied by performing dry sliding wear test using pin-on-disc wear tester. A L27 orthogonal array is selected for the analysis of the data. From the test results it is observed that sliding distance has the significant contribution in controlling the friction and wear behaviour of hybrid composites. A confirmation test is also carried out to verify the accuracy of the results obtained through the optimization. In addition an optical micrograph test is also performed on the wear tracks to study the wear mechanism. 展开更多
关键词 Metal Matrix Composites (MMCs) Friction Wear Taguchi method Grey RELATIONAL analysis analysis of Variance (ANOVA)
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Large deformation analysis of a cantilever beam made of axially functionally graded material by homotopy analysis method 被引量:2
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作者 Xin LIN Yixin HUANG +1 位作者 Yang ZHAO Tianshu WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第10期1375-1386,共12页
Large deformation of a cantilever axially functionally graded (AFG) beam subject to a tip load is analytically studied using the homotopy analysis method (HAM). It is assumed that its Young’s modulus varies along the... Large deformation of a cantilever axially functionally graded (AFG) beam subject to a tip load is analytically studied using the homotopy analysis method (HAM). It is assumed that its Young’s modulus varies along the longitudinal direction according to a power law. Taking the solution of the corresponding homogeneous beam as the initial guess and obtaining a convergence region by adjusting an auxiliary parameter, the analytical expressions for large deformation of the AFG beam are provided. Results obtained by the HAM are compared with those obtained by the finite element method and those in the previous works to verify its validity. Good agreement is observed. A detailed parametric study is carried out. The results show that the axial material variation can greatly change the deformed configuration, which provides an approach to control and manage the deformation of beams. By tailoring the axial material distribution, a desired deformed configuration can be obtained for a specific load. The analytical solution presented herein can be a helpful tool for this procedure. 展开更多
关键词 large deformation BEAM AXIALLY functionally GRADED (AFG) material Euler-Bernoulli BEAM HOMOTOPY analysis method (HAM)
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Analysis of Multipath and CW Interference Effects on GNSS Receivers with EMLP Discriminator 被引量:2
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作者 Bo Qu Jiaolong Wei +1 位作者 Shuangna Zhang Liang Bi 《Communications and Network》 2013年第3期80-85,共6页
Multipath and continuous wave (CW) interference may cause severe performance degradation of global navigation satellite system (GNSS) receivers. This paper analyzes the code tracking performance of early-minus-late po... Multipath and continuous wave (CW) interference may cause severe performance degradation of global navigation satellite system (GNSS) receivers. This paper analyzes the code tracking performance of early-minus-late power (EMLP) discriminator of GNSS receivers in the presence of multipath and CW interference. An analytical expression of the code tracking error is suggested for EMLP discriminator, and it can be used to assess the effect of multipath and CW interference. The derived expression shows that the combined effects include three components: multipath component;CW interference component and the combined component of multipath and CW interference. The effect of these components depends on some factors which can be classified into two categories: the receiving environment and the receiver parameters. Numerical results show how these factors affect the tracking performances. It is shown that the proper receiver parameters can suppress the combined effects of multipath and CW interference. 展开更多
关键词 analysis of MULTIPATH and CW interference Effects on GNSS RECEIVERS with EMLP DISCRIMINATOR
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Comparison of Calibration Curve Method and Partial Least Square Method in the Laser Induced Breakdown Spectroscopy Quantitative Analysis 被引量:1
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作者 Zhi-bo Cong Lan-xiang Sun +2 位作者 Yong Xin Yang Li Li-feng Qi 《Journal of Computer and Communications》 2013年第7期14-18,共5页
The Laser Induced Breakdown Spectroscopy (LIBS) is a fast, non-contact, no sample preparation analytic technology;it is very suitable for on-line analysis of alloy composition. In the copper smelting industry, analysi... The Laser Induced Breakdown Spectroscopy (LIBS) is a fast, non-contact, no sample preparation analytic technology;it is very suitable for on-line analysis of alloy composition. In the copper smelting industry, analysis and control of the copper alloy concentration affect the quality of the products greatly, so LIBS is an efficient quantitative analysis tech- nology in the copper smelting industry. But for the lead brass, the components of Pb, Al and Ni elements are very low and the atomic emission lines are easily submerged under copper complex characteristic spectral lines because of the matrix effects. So it is difficult to get the online quantitative result of these important elements. In this paper, both the partial least squares (PLS) method and the calibration curve (CC) method are used to quantitatively analyze the laser induced breakdown spectroscopy data which is obtained from the standard lead brass alloy samples. Both the major and trace elements were quantitatively analyzed. By comparing the two results of the different calibration method, some useful results were obtained: both for major and trace elements, the PLS method was better than the CC method in quantitative analysis. And the regression coefficient of PLS method is compared with the original spectral data with background interference to explain the advantage of the PLS method in the LIBS quantitative analysis. Results proved that the PLS method used in laser induced breakdown spectroscopy was suitable for simultaneous quantitative analysis of different content elements in copper smelting industry. 展开更多
关键词 LASER-INDUCED BREAKDOWN Spectroscopy (LIBS) PARTIAL Least SQUARE method (PLS) Matrix Effects Quantitative analysis
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Understanding roof deformation mechanics and parametric sensitivities of coal mine entries using the discrete element method 被引量:11
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作者 Rami Abousleiman Gabriel Walton Sankhaneel Sinha 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第1期123-129,共7页
Although conventional coal mine designs are conservative regarding pillar strength,local failures such as roof-falls and pillar bursts still affect mine safety and operations.Previous studies have identified that disc... Although conventional coal mine designs are conservative regarding pillar strength,local failures such as roof-falls and pillar bursts still affect mine safety and operations.Previous studies have identified that discontinuous,layered roof materials have some self-supporting capacity.This research is a preliminary step towards understanding these mechanics in coal-measure rocks.Although others have considered broad conceptual models and simplified analogs for mine roof behavior,this study presents a unique numerical model that more completely represents in-situ roof conditions.The discrete element method(DEM)is utilized to conduct a parametric analysis considering a range of in-situ stress ratios,material properties,and joint networks to determine the parameters controlling the stability of single-entries modeled in two-dimensions.Model results are compared to empirical observations of roof-support effectiveness(ARBS)in the context of the coal mine roof rating(CMRR)system.Results such as immediate roof displacement,overall stability,and statistical relationships between model parameters and outcomes are presented herein.Potential practical applications of this line of research include:(1)roof-support optimization for a range of coal-measure rocks,(2)establishment of a relationship between roof stability and pillar stress,and(3)determination of which parameters are most critical to roof stability and therefore require concentrated evaluation. 展开更多
关键词 Numerical modeling DISCRETE element method Coal mine ROOF rating analysis of ROOF bolt systems Sensitivity analysis Strain SOFTENING ubiquitous joints DISCRETE fracture network
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A Mathematical Approach Based on the Homotopy Analysis Method: Application to Solve the Nonlinear Harry-Dym (HD) Equation
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作者 Emran Khoshrouye Ghiasi Reza Saleh 《Applied Mathematics》 2017年第11期1546-1562,共17页
In this paper, the homotopy analysis method (HAM) has been employed to obtain the approximate analytical solution of the nonlinear Harry-Dym (HD) equation, which is one of the most important soliton equations. Utilizi... In this paper, the homotopy analysis method (HAM) has been employed to obtain the approximate analytical solution of the nonlinear Harry-Dym (HD) equation, which is one of the most important soliton equations. Utilizing the HAM, thereby employing the initial approximation, variations of the 7th-order approximation of the Harry-Dym equation is obtained. It is found that effect of the nonzero auxiliary parameter on convergence rate of the series solution is undeniable. It is also shown that, to some extent, order of the fractional derivative plays a fundamental role in the prediction of convergence. The final results reported by the HAM have been compared with the exact solution as well as those obtained through the other methods. 展开更多
关键词 Harry-Dym (HD) EQUATION Soliton HOMOTOPY analysis method (HAM) Auxiliary Parameter Convergence analysis Relative Error
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On the Homotopy Analysis Method and Optimal Value of the Convergence Control Parameter: Solution of Euler-Lagrange Equation
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作者 Jafar Saberi-Nadjafi Reza Buzhabadi Hassan Saberi Nik 《Applied Mathematics》 2012年第8期873-881,共9页
This paper presents, an efficient approach for solving Euler-Lagrange Equation which arises from calculus of variations. Homotopy analysis method to find an approximate solution of variational problems is proposed. An... This paper presents, an efficient approach for solving Euler-Lagrange Equation which arises from calculus of variations. Homotopy analysis method to find an approximate solution of variational problems is proposed. An optimal value of the convergence control parameter is given through the square residual error. By minimizing the the square residual error, the optimal convergence-control parameters can be obtained. It is showed that the homotopy analysis method was valid and feasible to the study of variational problems. 展开更多
关键词 HOMOTOPY analysis method CALCULUS of VARIATIONS VARIATIONAL Problems EULER-LAGRANGE Equation SQUARE Residual Error
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Homotopy Analysis Method for Solving Initial Value Problems of Second Order with Discontinuities
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作者 Waleed Al-Hayani Rasha Fahad 《Applied Mathematics》 2019年第6期419-434,共16页
In this paper, the standard homotopy analysis method was applied to initial value problems of the second order with some types of discontinuities, for both linear and nonlinear cases. To show the high accuracy of the ... In this paper, the standard homotopy analysis method was applied to initial value problems of the second order with some types of discontinuities, for both linear and nonlinear cases. To show the high accuracy of the solution results compared with the exact solution, a comparison of the numerical results was made applying the standard homotopy analysis method with the iteration of the integral equation and the numerical solution with the Simpson rule. Also, the maximum absolute error, , the maximum relative error, the maximum residual error and the estimated order of convergence were given. The research is meaningful and I recommend it to be published in the journal. 展开更多
关键词 HOMOTOPY analysis method Initial Value Problems Heaviside Step FUNCTION DIRAC Delta FUNCTION SIMPSON Rule
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Dynamic Analysis of Soil Structure Interaction Effect on Multi Story RC Frame
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作者 Hailu Getachew Kabtamu Gang Peng Denghong Chen 《Open Journal of Civil Engineering》 2018年第4期426-446,共21页
In this study dynamic analysis of Soil Structure Interaction (SSI) effect on multi story reinforced concrete (RC) frame founded on soft soil (flexible base) is made and compared with fixed base. Two model 2D RC frames... In this study dynamic analysis of Soil Structure Interaction (SSI) effect on multi story reinforced concrete (RC) frame founded on soft soil (flexible base) is made and compared with fixed base. Two model 2D RC frames with 7 and 12 story are selected for analysis. Winkler Spring and half space direct method models are used for flexible base for the frames founded on two types of soft soils with shear velocity Vs < 150 m/s Asper Seismic Codes of Chinese GB50011-2010 Soil IV and Ethiopian ES8-2015 soil D. The frames are subjected to strong ground motion matched to response spectrums of soft soil of Chinese GB50011-2010 and Ethiopian ES8-2015 for linear time history analysis. The dynamic analysis result shows Spring and Fixed base mass participation 90% reaches in 2 or 3 modes but in direct method 11 to 30 modes for story 12 and 7 respectively. However, both flexible base models have bigger fundamental period of vibration and inter story drift but smaller base shear than fixed base. In addition, within the flexible base models the inter-story drift, second order effect (P-Δ) and Story shear distribution are different along the height of frames. The spring model shows larger Story drift and second order effect (P-Δ) at the bottom of Story for both soft soils types. On the other hand, half space direct method model indicates value reverse to spring model;it gives bigger Story drift and P-Δ effect in the top stories than fixed base. Finally, this study concludes that base shear reduction due to SSI may not be always beneficial. Because the gravity load is constant in both fixed and flexible bases that cause bigger P-Δ effect at the bottom stories due to increase, inter story drift and decrease story shear in flexible base. 展开更多
关键词 Soil Structure Interaction Dynamic analysis Fixed BASE Flexible BASE Direct method WINKLER Spring PERIOD of Vibration STORY SHEAR STORY DRIFT and P-Δ Effect
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