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The Extension Methods and Fecision-making Analysis on the Planting Dtructure of Dlope Garmland in Northern Shaanxi
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作者 李洋 杨茂盛 Mao-sheng 《Agricultural Science & Technology》 CAS 2010年第5期178-181,共4页
Based on the resent research about the planting structure of slope farmland in northern Shaanxi,in order to increase the native's income,we use the theory of the extension methods to analyze the planting structure... Based on the resent research about the planting structure of slope farmland in northern Shaanxi,in order to increase the native's income,we use the theory of the extension methods to analyze the planting structure of slope farmland,so that we can get the extensive strategy,and put them into use for planting of slope farmland to make the native's income higher. 展开更多
关键词 Region in northern Shaanxi Slope farmland The extension methods and Decision-making
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Engineering Geological Zoning of Soft-Soil Foundation Based on Combination Weighting and Extension Methods 被引量:1
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作者 孙明乾 王清 +4 位作者 陈剑平 李严 宋盛渊 鲍硕超 阮云凯 《Journal of Donghua University(English Edition)》 EI CAS 2016年第3期453-461,共9页
Different criteria and factors are used in different methods of soft soil foundation settlement calculation and engineering geological zoning.The methods used are not universally suitable for complex geological enviro... Different criteria and factors are used in different methods of soft soil foundation settlement calculation and engineering geological zoning.The methods used are not universally suitable for complex geological environments.The post-construction settlement of soft soil foundations are especially large and difficult to calculate.In addition,there are many deficiencies in the current methods used for engineering geological zoning.Focusing on the need of establishing engineering geological zoning for areas with soft soil foundations in the Tianjin Marine Economic Area,combination weighting and extension methods were introduced.An evaluation model for the settlement of soft soil foundations was established using multiple factors and large amounts of data.This evaluation model is accurate and objective for delineating engineering geological zoning.These methods eliminate deficiencies by considering both objective and subjective factors,and help obtain an objective and accurate result. 展开更多
关键词 soft soil foundation engineering geological zoning combination weighting method extension method
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New approach to develop a 3D non-isothermal computational framework for injection molding process based on level set method 被引量:2
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作者 Xin Zhuang Jie Ouyang +1 位作者 Chuntao Jiang Qingsheng Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第7期832-842,共11页
The simulation of three-dimensional (3D) non-isothermal, non-Newtonian fluid filling process is an extremely difficult task and remains a challenging problem, which includes polymer melt flow with free surface coupl... The simulation of three-dimensional (3D) non-isothermal, non-Newtonian fluid filling process is an extremely difficult task and remains a challenging problem, which includes polymer melt flow with free surface coupled with transient heat transfer. This paper presents a full 3D non-isothermal two-phase flow model to predict the complex flow in melt filling process, where the Cross-WLF model is applied to characterize the rheological behav- ior of polymer melt. The governing equations are solved using finite volume method with SIMPLEC algorithm on collocated grids and the melt front is accurately captured by a high resolution level set method. A domain exten- sion technique is adopted to deal with the complex cavities, which greatly reduces the computational burden. To verify the validity of the developed 3D approach, the melts filling processes in two thin rectangular cavities (one of them with a cylindrical insert) are simulated. The predicted melt front interfaces are in good agreement with the experiment and commercial software prediction. For a case with a rather complex cavity, the dynamic filling process in a hemispherical shell is successfully simulated. All of the numerical results show that the developed numerical procedure can provide a reasonable orediction for injection molding process. 展开更多
关键词 Injection moldingNon-isothermalFinite voIume/SIMPLEC methodDomain extension techniqueHigh resolution level set method
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A SELF-SIMILAR CRACK EXPANSION METHOD FOR THREE-DIMENSIONAL CRACKS IN AN INFINITE OR SEMI-INFINITE MEDIUM
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作者 Brian Moran Ted Belytschko 《Acta Mechanica Solida Sinica》 SCIE EI 1996年第3期217-235,共19页
The Self-Similar Crack Expansion (SSCE) method is used to calculate stress intensity factors for three-dimensional cracks in an infinite medium or semi-infinite medium by the boundary integral element technique, where... The Self-Similar Crack Expansion (SSCE) method is used to calculate stress intensity factors for three-dimensional cracks in an infinite medium or semi-infinite medium by the boundary integral element technique, whereby, the stress intensity factors at crack tips are determined by calculating the crack-opening displacements over the crack surface. For elements on the crack surface, regular integrals and singular integrals are precisely evaluated based on closed form expressions, which improves the accuracy. Examples shaw that this method yields very accurate results for stress intensity factors of penny-shaped cracks and elliptical cracks in the full space, with errors of less than 1% as compared with analytical solutions. The stress intensity factors of subsurface cracks ate in good agreement with other analytical solutions. 展开更多
关键词 self-similar crack expansion stress intensity crack extension method 3-D cracks
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SELF-SIMILAR CRACK EXPANSION METHOD FOR THE STRESS INTENSITY FACTOR ANALYSIS
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作者 Yonglin Xu Ted Belytschko, Dept. of Civil Engineering, Northwestern University, Evanston, IL 60208, U. S. A 《Acta Mechanica Solida Sinica》 SCIE EI 1996年第2期104-123,共20页
The Self-Similar Crack Expansion (SSCE) method is proposed to evaluate stress intensity factors at crack tips, whereby stress intensity factors of a crack can be determined by the crack opening displacement over the c... The Self-Similar Crack Expansion (SSCE) method is proposed to evaluate stress intensity factors at crack tips, whereby stress intensity factors of a crack can be determined by the crack opening displacement over the crack, not just by the local displacement around the crack tip. The crack expansion rate is estimated by taking advantage of the crack self-similarity. Therefore, the accuracy of the calculation is improved. The singular integrals on crack tip elements are also analyzed and are precisely evaluated in terms of a special integral analysis. Combination of these two techniques greatly increases the accuracy in estimating the stress distribution around the crack tip. A variety of two-dimensional cracks, such as subsurface cracks, edge cracks, and their interactions are calculated in terms of the self-similar expansion rate. Solutions are satisfied with errors less than 0.5% as compared with the analytical solutions. Based on the calculations of the crack interactions, a theory for crack interactions is proposed such that for a group of aligned cracks the summation of the square of SIFs at the right tips of cracks is always equal to that at the left tips of cracks. This theory was proved by the mehtod of Self-Similar Crack Expansion in this paper. 展开更多
关键词 self-similar crack expansion stress intensity factor crack extension method
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THE APPLICATION AND EXTENSION OF SACHS METHOD
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作者 宋顺成 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第12期1163-1169,共7页
In this paper,we present the simplification of Sachs formulas for the measurement and calculation of the residual stresses of the cylinder only with the plane stresses. Furthermore, we present the method for the measu... In this paper,we present the simplification of Sachs formulas for the measurement and calculation of the residual stresses of the cylinder only with the plane stresses. Furthermore, we present the method for the measurement and calculation of the residual stresses of the cylinder not only with the finite length but with the longitudinal stress. These can be applied to the investigation on the residual stresses of the autofretted gun tube. 展开更多
关键词 THE APPLICATION AND EXTENSION OF SACHS method LENGTH
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Asymmetric breakup of a droplet in an axisymmetric extensional flow
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作者 Dongming Yu Manman Zheng +1 位作者 Taoming Jin Jingtao Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第1期63-70,共8页
The asymmetric breakups of a droplet in an axisymmetric cross-like microfluidic device are investigated by using a three-dimensional volume of fluid(VOF) multiphase numerical model. Two kinds of asymmetries(droplet lo... The asymmetric breakups of a droplet in an axisymmetric cross-like microfluidic device are investigated by using a three-dimensional volume of fluid(VOF) multiphase numerical model. Two kinds of asymmetries(droplet location deviation from the symmetric geometry center and different flow rates at two symmetric outlets) generate asymmetric flow fields near the droplet, which results in the asymmetric breakup of the latter. Four typical breakup regimes(no breakup, one-side breakup, retraction breakup and direct breakup) have been observed.Two regime maps are plotted to describe the transition from one regime to another for the two types of different asymmetries, respectively. A power law model, which is based on the three critical factors(the capillary number,the asymmetry of flow fields and the initial volume ratio), is employed to predict the volume ratio of the two unequal daughter droplets generated in the direct breakup. The influences of capillary numbers and the asymmetries have been studied systematically in this paper. The larger the asymmetry is, the bigger the oneside breakup zone is. The larger the capillary number is, the more possible the breakup is in the direct breakup zone. When the radius of the initial droplet is 20 μm, the critical capillary numbers are 0.122, 0.128, 0.145,0.165, 0.192 and 0.226 for flow asymmetry factor AS= 0.05, 0.1, 0.2, 0.3, 0.4 and 0.5, respectively, in the flow system whose asymmetry is generated by location deviations. In the flow system whose asymmetry is generated by two different flow rates at two outlets, the critical capillary numbers are 0.121, 0.133, 0.145, 0.156 and 0.167 for AS= 1/21, 3/23, 1/5, 7/27 and 9/29, respectively. 展开更多
关键词 Asymmetric breakup Droplet Volume of fluid method Axisymmetric extensional flow
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The Convergences Comparison between the Halley’s Method and Its Extended One Based on Formulas Derivation and Numerical Calculations
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作者 Shunji Horiguchi 《Applied Mathematics》 2016年第18期2394-2410,共17页
The purpose of this paper is that we give an extension of Halley’s method (Section 2), and the formulas to compare the convergences of the Halley’s method and extended one (Section 3). For extension of Halley’s met... The purpose of this paper is that we give an extension of Halley’s method (Section 2), and the formulas to compare the convergences of the Halley’s method and extended one (Section 3). For extension of Halley’s method we give definition of function by variable transformation in Section 1. In Section 4 we do the numerical calculations of Halley’s method and extended one for elementary functions, compare these convergences, and confirm the theory. Under certain conditions we can confirm that the extended Halley’s method has better convergence or better approximation than Halley’s method. 展开更多
关键词 Recurrence Formula Newton’s method Halley’s method Extension of Halley’s method Third-Order Convergence
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The Formulas to Compare the Convergences of Newton’s Method and the Extended Newton’s Method (Tsuchikura-Horiguchi Method) and the Numerical Calculations
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作者 Shunji Horiguchi 《Applied Mathematics》 2016年第1期40-60,共21页
This paper gives the extension of Newton’s method, and a variety of formulas to compare the convergences for the extension of Newton’s method (Section 4). Section 5 gives the numerical calculations. Section 1 introd... This paper gives the extension of Newton’s method, and a variety of formulas to compare the convergences for the extension of Newton’s method (Section 4). Section 5 gives the numerical calculations. Section 1 introduces the three formulas obtained from the cubic equation of a hearth by Murase (Ref. [1]). We find that Murase’s three formulas lead to a Horner’s method (Ref. [2]) and extension of a Newton’s method (2009) at the same time. This shows originality of Wasan (mathematics developed in Japan) in the Edo era (1603-1868). Suzuki (Ref. [3]) estimates Murase to be a rare mathematician in not only the history of Wasan but also the history of mathematics in the world. Section 2 gives the relations between Newton’s method, Horner’s method and Murase’s three formulas. Section 3 gives a new function defined such as . 展开更多
关键词 Recurrence Formula Newton-Raphson’s method (Newton’s method) Extension of Newton’s method
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Dynamic properties of fuzzy Petri net model and related analysis 被引量:1
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作者 周恺卿 Azlan Mohd Zain 莫礼平 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4717-4723,共7页
Fuzzy Petri net(FPN) has been extensively applied in industrial fields for knowledge-based systems or systems with uncertainty.Although the applications of FPN are known to be successful,the theoretical research of FP... Fuzzy Petri net(FPN) has been extensively applied in industrial fields for knowledge-based systems or systems with uncertainty.Although the applications of FPN are known to be successful,the theoretical research of FPN is still at an initial stage.To pave a way for further study,this work explores related dynamic properties of FPN including reachability,boundedness,safeness,liveness and fairness.The whole methodology is divided into two phases.In the first phase,a comparison between elementary net system(EN_system) and FPN is established to prove that the FPN is an extensive formalism of Petri nets using a backwards-compatible extension method.Next,current research results of dynamic properties are utilized to analyze FPN model.The results illustrate that FPN model is bounded,safe,weak live and fair,and can support theoretical evidences for designing related decomposition algorithm. 展开更多
关键词 fuzzy Petri net elementary net system backwards-compatible extension method dynamic properties
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HERMITE SCATTERED DATA FITTING BY THE PENALIZED LEAST SQUARES METHOD
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作者 Tianhe Zhou Danfu Han 《Journal of Computational Mathematics》 SCIE CSCD 2009年第6期802-811,共10页
Given a set of scattered data with derivative values. If the data is noisy or there is an extremely large number of data, we use an extension of the penalized least squares method of von Golitschek and Schumaker [Serd... Given a set of scattered data with derivative values. If the data is noisy or there is an extremely large number of data, we use an extension of the penalized least squares method of von Golitschek and Schumaker [Serdica, 18 (2002), pp.1001-1020] to fit the data. We show that the extension of the penalized least squares method produces a unique spline to fit the data. Also we give the error bound for the extension method. Some numerical examples are presented to demonstrate the effectiveness of the proposed method. 展开更多
关键词 Bivariate splines Scattered data fitting Extension of penalized least squares method.
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Estimating high-spatial resolution surface daily longwave radiation from the instantaneous Global LAnd Surface Satellite(GLASS)longwave radiation product 被引量:1
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作者 Qi Zeng Jie Cheng 《International Journal of Digital Earth》 SCIE 2021年第11期1674-1704,共31页
In this paper,time extension methods,originally designed for clear-sky land surface conditions,are used to estimate high-spatial resolution surface daily longwave(LW)radiation from the instantaneous Global LAnd Surfac... In this paper,time extension methods,originally designed for clear-sky land surface conditions,are used to estimate high-spatial resolution surface daily longwave(LW)radiation from the instantaneous Global LAnd Surface Satellite(GLASS)longwave radiation product.The performance of four time methods were first tested by using ground based flux measurements that were collected from 141 global sites.Combined with the accuracy of daily LW radiation estimated from the instantaneous GLASS LW radiation,the linear sine interpolation method performs better than the other methods and was employed to estimate the daily LW radiation as follows:The bias/Root Mean Square Error(RMSE)of the linear sine interpolation method were−6.30/15.10 W/m^(2)for the daily longwave upward radiation(LWUP),−1.65/27.63 W/m2 for the daily longwave downward radiation(LWDN),and 4.69/26.42 W/m^(2)for the daily net longwave radiation(LWNR).We found that the lengths of the diurnal cycle of LW radiation are longer than the durations between sunrise and sunset and we proposed increasing the day length by 1.5 h.The accuracies of daily LW radiation were improved after adjusting the day length.The bias/RMSE were−4.15/13.74 W/m2 for the daily LWUP,−1.3/27.52 W/m^(2)for the daily LWDN,and 2.85/25.91 W/m^(2)for the daily LWNR.We are producing long-term surface daily LW radiation values from the GLASS LW radiation product. 展开更多
关键词 Surface longwave radiation surface longwave net radiation GLASS time extension method surface radiation budget
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Properties of Solutions to Fractional Laplace Equation with Singular Term
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作者 WANG Xinjing 《Journal of Partial Differential Equations》 CSCD 2023年第2期191-202,共12页
The aim of the paper is to study the properties of positive classical solutions to the fractional Laplace equation with the singular term.Using the extension method,we prove the nonexistence and symmetric of solutions... The aim of the paper is to study the properties of positive classical solutions to the fractional Laplace equation with the singular term.Using the extension method,we prove the nonexistence and symmetric of solutions to the singular fractional equation. 展开更多
关键词 Fractional Laplace equation extension method method of moving planes SYMMETRY
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Model for Evaluating the Ecological Health of Municipal Solid Waste Treatment System
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作者 王艳明 张乾飞 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第5期629-634,共6页
Ecological municipal solid waste (MSW) treatment systems are complex systems engineering concerning with multiple objectives and hierarchical levels. By combining an extension method with fuzzy logic theory, this pape... Ecological municipal solid waste (MSW) treatment systems are complex systems engineering concerning with multiple objectives and hierarchical levels. By combining an extension method with fuzzy logic theory, this paper investigated key technologies required by the comprehensive evaluation of ecological health. The method includes the construction of an evaluation system, quantification of evaluation indices, development of a matter-element model, development of an extension evaluation method, and assignment of a blended weight that combines subjectively and objectively estimated weights. This approach was used to develop a comprehensive model for evaluating the ecological health of an ecological treatment system for MSW. The model was then applied to a case study, and the results demonstrated that the model is a reasonable and effective. 展开更多
关键词 municipal solid waste(MSW) ecological treatment ecological health extension evaluation method comprehensive evaluation
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