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界理论对语境中英语限定词词组的影响
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作者 邓梦林 《湖南人文科技学院学报》 2011年第5期94-96,共3页
英语的可数或不可数名词能够突破自己默认的词汇意义,被语境暂时"解界"或"限界"成具有相反语义特征的不可数或可数名词,继而影响冠词的选择。英语限定词词组中冠词与名词的搭配受语境约束。
关键词 可数名词 不可数名词 解界 限界 语境
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英语现在进行体认知机制的界限分析
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作者 仇伟 王珊 《活力》 2019年第7期251-251,共1页
“有界-无界”是人类认知机制的一部分,因此理应成为英语现在进行体认知机制之一。在Langacker认知语法理论基础之上,本研究运用划界理论对英语现在进行体的认知机制问题进行探究。研究得出划界解界是英语现在进行体的认知机制之一,给... “有界-无界”是人类认知机制的一部分,因此理应成为英语现在进行体认知机制之一。在Langacker认知语法理论基础之上,本研究运用划界理论对英语现在进行体的认知机制问题进行探究。研究得出划界解界是英语现在进行体的认知机制之一,给出了英语现在进行体认知机制的流程图,从而更全面、更细致地了解英语现在进行体的认知机制问题。 展开更多
关键词 英语现在进行体 划界与解界 认知机制
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Relationship between Al(OH)_3 solubility and particle size in synthetic Bayer liquors 被引量:5
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作者 李小斌 阎丽 +5 位作者 赵东峰 周秋生 刘桂华 彭志宏 杨帅帅 齐天贵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第5期1472-1479,共8页
Surface tension of sodium aluminate solution and the contact angle between Al(OH)3 particles and aluminate solution were measured, then the dependence of Al(OH)3 solubility on its particle size was calculated and ... Surface tension of sodium aluminate solution and the contact angle between Al(OH)3 particles and aluminate solution were measured, then the dependence of Al(OH)3 solubility on its particle size was calculated and thus the variation of the critical nucleus sizes was determined based on the Ostwald ripening formula. The results show that the Al(OH)3 solubility in sodium aluminate solution decreases with the increment of particle size, and the critical nucleus sizes increase with the rise of alkali concentration, caustic ratio and precipitation temperature. The results also imply that the presence of small particles in seeded precipitation system is an important factor to limit the depth of precipitation. 展开更多
关键词 Bayer liquor Al(OH)3 interfacial property SOLUBILITY critical nucleus size
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On the Existence of Periodic Solutions of a Class Nonlinear Differential Systems 被引量:1
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作者 李林 徐琛梅 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期69-77,共9页
One method to show the existence of ω-periodic system is given. This method is based on the ultimately boundedness of the solution of the systems. By using comparing theorem and discussing some one dimensional equati... One method to show the existence of ω-periodic system is given. This method is based on the ultimately boundedness of the solution of the systems. By using comparing theorem and discussing some one dimensional equations the main results are obtained. 展开更多
关键词 differential system periodic solutions BOUNDEDNESS
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Improved Euler method for the interpretation of potential data based on the ratio of the vertical fi rst derivative to analytic signal 被引量:2
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作者 郭灿灿 熊盛青 +1 位作者 薛典军 王林飞 《Applied Geophysics》 SCIE CSCD 2014年第3期331-339,352,共10页
We propose a new automatic method for the interpretation of potential fi eld data, called the RDAS–Euler method, which is based on Euler's deconvolution and analytic signal methods. The proposed method can estimate ... We propose a new automatic method for the interpretation of potential fi eld data, called the RDAS–Euler method, which is based on Euler's deconvolution and analytic signal methods. The proposed method can estimate the horizontal and vertical extent of geophysical anomalies without prior information of the nature of the anomalies(structural index). It also avoids inversion errors because of the erroneous choice of the structural index N in the conventional Euler deconvolution method. The method was tested using model gravity anomalies. In all cases, the misfi t between theoretical values and inversion results is less than 10%. Relative to the conventional Euler deconvolution method, the RDAS–Euler method produces inversion results that are more stable and accurate. Finally, we demonstrate the practicability of the method by applying it to Hulin Basin in Heilongjiang province, where the proposed method produced more accurate data regarding the distribution of faults. 展开更多
关键词 Euler deconvolution analytic signal edge identifi cation structural index
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Lagrangian stability of a class of second-order periodic systems with nonlinear damping term
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作者 江舜君 方芳 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期130-134,共5页
By the iteration of the KAM, the following second- order differential equation ( Фp (x′))′ + F(x, x′, t) + ω^PФp (x′) +α│x│^l +e(x, t) =0 is studied, where Фp(S) = │S│^p-2s, p 〉 1, α〉 0... By the iteration of the KAM, the following second- order differential equation ( Фp (x′))′ + F(x, x′, t) + ω^PФp (x′) +α│x│^l +e(x, t) =0 is studied, where Фp(S) = │S│^p-2s, p 〉 1, α〉 0 and ω 〉 0 are positive constants, and l satisfies - 1 〈ω 〈p + 2. Under some assumptions on the parities of F(x, x′, t) and e (x, t), by a small twist theorem of reversible mapping, the existence of quasi-periodic solutions and boundedness of all the solutions are obtained. 展开更多
关键词 reversible system KAM theorem boundedness ofsolutions
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FINITE ELEMENT-ARTIFICIAL TRANSMITTING BOUNDARY METHOD FOR WAVE SCATTERING FROM IRREGULAR CYLINDER 被引量:1
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作者 杨吉生 徐立军 +1 位作者 邢昌玉 杨光 《Transactions of Tianjin University》 EI CAS 1997年第2期36-39,共4页
The finite element artificial transmitting boundary method is employed here to treat the near field scattering of a cylindrical wave from an irregular cylinder. A comparison is made between this method and the analy... The finite element artificial transmitting boundary method is employed here to treat the near field scattering of a cylindrical wave from an irregular cylinder. A comparison is made between this method and the analytical one. And then examples are given to demonstrate the solution of several problems of the irregular object scattering. The method can not only produce clear physical pictures, but can efficiently handle many complicated scattering problems. 展开更多
关键词 finite elements artificial transmitting boundary SCATTERING
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The Estimation for Lower Bounds of the Solutions of Fermat's Equation
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作者 乐茂华 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期52-55,共4页
Let p be a prime with p≡3(mod 4). In this paper,by using some results relate the representation of integers by primitive binary quadratic forms,we prove that if x,y,z are positive integers satisfying x^p+y^p=z^p, p|x... Let p be a prime with p≡3(mod 4). In this paper,by using some results relate the representation of integers by primitive binary quadratic forms,we prove that if x,y,z are positive integers satisfying x^p+y^p=z^p, p|xyz, x<y<z, then y>p^(6p-2)/2. 展开更多
关键词 Fermat's last theorem integer solution lower bound
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Subspaces for weak mild solutions of the second order abstract differential equation
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作者 王梅英 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期313-316,共4页
The topic on the subspaces for the polynomially or exponentially bounded weak mild solutions of the following abstract Cauchy problem d^2/(dr^2)u(t,x)=Au(t,x);u(0,x)=x,d/(dt)u(0,x)=0,x∈X is studied, wher... The topic on the subspaces for the polynomially or exponentially bounded weak mild solutions of the following abstract Cauchy problem d^2/(dr^2)u(t,x)=Au(t,x);u(0,x)=x,d/(dt)u(0,x)=0,x∈X is studied, where A is a closed operator on Banach space X. The case that the problem is ill-posed is treated, and two subspaces Y(A, k) and H(A, ω) are introduced. Y(A, k) is the set of all x in X for which the second order abstract differential equation has a weak mild solution v( t, x) such that ess sup{(1+t)^-k|d/(dt)〈v(t,x),x^*〉|:t≥0,x^*∈X^*,|x^*‖≤1}〈+∞. H(A, ω) is the set of all x in X for which the second order abstract differential equation has a weak mild solution v(t,x)such that ess sup{e^-ωl|d/(dt)〈v(t,x),x^*)|:t≥0,x^*∈X^*,‖x^*‖≤1}〈+∞. The following conclusions are proved that Y(A, k) and H(A, ω) are Banach spaces, and both are continuously embedded in X; the restriction operator A | Y(A,k) generates a once-integrated cosine operator family { C(t) }t≥0 such that limh→0+^-1/h‖C(t+h)-C(t)‖Y(A,k)≤M(1+t)^k,arbitary t≥0; the restriction operator A |H(A,ω) generates a once- integrated cosine operator family {C(t)}t≥0 such that limh→0+^-1/h‖C(t+h)-C(t)‖H(A,ω)≤≤Me^ωt,arbitary t≥0. 展开更多
关键词 second order abstract differential equation polynomially bounded solution cosine operator function
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Optimal Boundary Control Method for Domain Decomposition Algorithm
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作者 闫桂峰 冯恩民 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期113-119,共7页
To study the domain decomposition algorithms for the equations of elliptic type, the method of optimal boundary control was used to advance a new procedure for domain decomposition algorithms and regularization method... To study the domain decomposition algorithms for the equations of elliptic type, the method of optimal boundary control was used to advance a new procedure for domain decomposition algorithms and regularization method to deal with the ill posedness of the control problem. The determination of the value of the solution of the partial differential equation on the interface——the key of the domain decomposition algorithms——was transformed into a boundary control problem and the ill posedness of the control problem was overcome by regularization. The convergence of the regularizing control solution was proven and the equations which characterize the optimal control were given therefore the value of the unknown solution on the interface of the domain would be obtained by solving a series of coupling equations. Using the boundary control method the domain decomposion algorithm can be carried out. 展开更多
关键词 domain decomposition methods(DDM) boundary control REGULARIZATION coupling equations
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Oscillation of Unstable Second Order Neutral Differential Equations with Positive and Negative Coefficients
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作者 徐继军 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期72-75,共4页
This paper discusses a class of unstable second order neutral differential equations with positive and negative coeffcients. Sufficient conditions for all bounded solutions of the equations to be oscillatory are obtai... This paper discusses a class of unstable second order neutral differential equations with positive and negative coeffcients. Sufficient conditions for all bounded solutions of the equations to be oscillatory are obtained. 展开更多
关键词 neutral equation UNSTABLE OSCILLATION
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Data mining and well logging interpretation: application to a conglomerate reservoir 被引量:8
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作者 石宁 李洪奇 罗伟平 《Applied Geophysics》 SCIE CSCD 2015年第2期263-272,276,共11页
Data mining is the process of extracting implicit but potentially useful information from incomplete, noisy, and fuzzy data. Data mining offers excellent nonlinear modeling and self-organized learning, and it can play... Data mining is the process of extracting implicit but potentially useful information from incomplete, noisy, and fuzzy data. Data mining offers excellent nonlinear modeling and self-organized learning, and it can play a vital role in the interpretation of well logging data of complex reservoirs. We used data mining to identify the lithologies in a complex reservoir. The reservoir lithologies served as the classification task target and were identified using feature extraction, feature selection, and modeling of data streams. We used independent component analysis to extract information from well curves. We then used the branch-and- bound algorithm to look for the optimal feature subsets and eliminate redundant information. Finally, we used the C5.0 decision-tree algorithm to set up disaggregated models of the well logging curves. The modeling and actual logging data were in good agreement, showing the usefulness of data mining methods in complex reservoirs. 展开更多
关键词 Data mining well logging interpretation independent component analysis branch-and-bound algorithm C5.0 decision tree
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Generation of iPS cells using defined factors linked via the self-cleaving 2A sequences in a single open reading frame 被引量:12
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作者 Lijian Shao Wei Feng +9 位作者 Yan Sun Hao Bai Jun Liu Caroline Currie Jaejung Kim Rafael Gama Zack Wang Zhijian Qian Lucy Liaw Wen-Shu Wu 《Cell Research》 SCIE CAS CSCD 2009年第3期296-306,共11页
Generation of induced pluripotent stem (iPS) cells from somatic cells has been achieved successfully by simultaneous viral transduction of defined reprogramming transcription factors (TFs). However, the process re... Generation of induced pluripotent stem (iPS) cells from somatic cells has been achieved successfully by simultaneous viral transduction of defined reprogramming transcription factors (TFs). However, the process requires multiple viral vectors for gene delivery. As a result, generated iPS cells harbor numerous viral integration sites in their genomes. This can increase the probability of gene mutagenesis and genomic instability, and present significant barriers to both research and clinical application studies of iPS cells. In this paper, we present a simple lentivirus reprogramming system in which defined factors are fused in-frame into a single open reading frame (ORF) via self-cleaving 2A sequences. A GFP marker is placed downstream of the transgene to enable tracking of transgene expression. We demonstrate that this polycistronic expression system efficiently generates iPS cells. The generated iPS cells have normal karyotypes and are similar to mouse embryonic stem cells in morphology and gene expression. Moreover, they can differentiate into cell types of the three embryonic germ layers in both in vitro and in vivo assays. Remarkably, most of these iPS cells only harbor a single copy of viral vector. This system provides a valuable tool for generation of iPS cells, and our data suggest that the balance of expression of transduced reprogramming TFs in each cell is essential for the reprogramming process. More importantly, when delivered by non-integrating gene-delivery systems, this re-engineered single ORF will facilitate efficient generation of human iPS cells free of genetic modifications. 展开更多
关键词 iPS cells embryonic stem cells self-cleaving 2A sequences somatic cell reprogramming polycistronic lentiviralvector
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Ground states for asymptotically periodic quasilinear Schrdinger equations with critical growth
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作者 张慧 张福保 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期352-354,共3页
For a class of asymptotically periodic quasilinear Schr?dinger equations with critical growth the existence of ground states is proved.First applying a change of variables the quasilinear Schr?dinger equations are r... For a class of asymptotically periodic quasilinear Schr?dinger equations with critical growth the existence of ground states is proved.First applying a change of variables the quasilinear Schr?dinger equations are reduced to semilinear Schr?dinger equations in which the corresponding functional is well defined in H1 RN .Moreover there is a one-to-one correspondence between ground states of the semilinear Schr?dinger equations and the quasilinear Schr?dinger equations.Then the mountain-pass theorem is used to find nontrivial solutions for the semilinear Schr?dinger equations. Finally under certain monotonicity conditions using the Nehari manifold method and the concentration compactness principle the nontrivial solutions are found to be exactly the same as the ground states of the semilinear Schr?dinger equations. 展开更多
关键词 quasilinear Schrodinger equation variationalmethod ground state critical growth
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Some properties and structures of solutions of the swift-Hohenberg equation
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作者 周华 唐健 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期301-306,共6页
Stationary even periodic solutions of the Swift-Hohenberg equation areanalyzed for the critical parameter k = 1, and it is proved that there exist periodic solutionshaving the same energy as the constant solution u = ... Stationary even periodic solutions of the Swift-Hohenberg equation areanalyzed for the critical parameter k = 1, and it is proved that there exist periodic solutionshaving the same energy as the constant solution u = 0. For k ≤ 0, some qualitative properties ofthe solutions are also proved. 展开更多
关键词 shooting technique swift-hohenberg equation critical point PERIODICSOLUTION
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SOLVABILITY RESULTS OF A CONDITIONAL INPUT-OUTPUT EQUATION BASED ON A TYPE OF NONLINEAR LEONTIEF MODEL
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作者 胡问鸣 刘颖范 沙春林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期224-229,共6页
A class of nonlinear and continuous type Leontief model and its corresponding conditional input-output equation are introduced, and two basic problems under the so called positive or negative boundary assumption are p... A class of nonlinear and continuous type Leontief model and its corresponding conditional input-output equation are introduced, and two basic problems under the so called positive or negative boundary assumption are presented. By approaches of nonlinear analysis some solvability results of this equation and continuous perturbation properties of the relative solution sets are obtained, and some economic significance are illustrated by the remark. 展开更多
关键词 conditional Leontief model input-output equation positive (negative) boundary assumption nonlinear analysis SOLVABILITY continuous disturbance
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Solubility of Piperine in Supercritical and Near Critical Carbon Dioxide 被引量:6
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作者 A.C. Kumoro Harcharan Singh Masitah Hasan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第6期1014-1020,共7页
Piperine is a member of the lipids family commonly found in peppercorn, ginger and other natural sources and is grouped as an alkaloid. The solubility of piperine has been determined in carbon dioxide at near critical... Piperine is a member of the lipids family commonly found in peppercorn, ginger and other natural sources and is grouped as an alkaloid. The solubility of piperine has been determined in carbon dioxide at near critical and supercritical conditions in a dynamic extraction apparatus. The conditions studied were at pressures ranging from 10 to 20 MPa and temperatures at 293, 300, 313, 323 and 333 K. The results showed that piperine solubility increased with increasing pressure at all temperatures studied. The solubility of plperme in near critical conditions was slightly higher than that at supercritical conditions only at the low-pressure range. Two semi-empirical density dependent correlations, namely the Chrastil model and the Dilute Solution model, were also used to estimate the solubility data. Although both models showed good correlation with the solubility data, the Dilute Solution model performed better prediction than the Chrastil model. 展开更多
关键词 SOLUBILITY PIPERINE SUPERCRITICAL near critical carbon dioxide
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Some new bound estimates of the Hermitian positive definite solutions of the nonlinear matrix equation X^s+ A~*X^(-t) A = Q 被引量:1
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作者 Cai Jing Chen Jianlong 《Journal of Southeast University(English Edition)》 EI CAS 2019年第1期142-146,共5页
The range and existence conditions of the Hermitian positive definite solutions of nonlinear matrix equations Xs+A*X-tA=Q are studied, where A is an n×n non-singular complex matrix and Q is an n×n Hermitian ... The range and existence conditions of the Hermitian positive definite solutions of nonlinear matrix equations Xs+A*X-tA=Q are studied, where A is an n×n non-singular complex matrix and Q is an n×n Hermitian positive definite matrix and parameters s,t>0. Based on the matrix geometry theory, relevant matrix inequality and linear algebra technology, according to the different value ranges of the parameters s,t, the existence intervals of the Hermitian positive definite solution and the necessary conditions for equation solvability are presented, respectively. Comparing the existing correlation results, the proposed upper and lower bounds of the Hermitian positive definite solution are more accurate and applicable. 展开更多
关键词 nonlinear matrix equation Hermitian positive definite solution solution bound matrix inequality
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Amino Acids Production from Fish Proteins Hydrolysis in Subcritical Water 被引量:9
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作者 朱宪 朱超 +1 位作者 赵亮 程洪斌 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第3期456-460,共5页
The hydrolysis technology and reaction kinetics for amino acids production from fish proteins in subcritical water reactor without catalysts were investigated in a reactor with volume of 400 ml under the conditions of... The hydrolysis technology and reaction kinetics for amino acids production from fish proteins in subcritical water reactor without catalysts were investigated in a reactor with volume of 400 ml under the conditions of reaction temperature from 180-320℃, pressure from 5-26 MPa, and time from 5-60 rain. The quality and quantity of amino acids in hydrolysate were determined by bioLiquid chromatography, and 17 kinds of amino acids were obtained. For the important 8 amino acids, the experiments were conducted to examine the effects of reaction temperature, pressure and time on amino acids yield. The optimum conditions for high yield are obtained from the experimental results. It is found that the nitrogen and carbon dioxide atmosphere should be used for leucine, isoleucine and histidine production while the air atmosphere might be used for other amino acids. The reaction time of 30 rain and the experimental temperature of 220℃, 240℃ and 260℃ were adopted for reaction kinetic research. The total yield of amino acids versus reaction time have been examined experimentally. According to these experimental data and under the condition of water excess, the macroscopic reaction kinetic equation of fish proteins hydrolysis was obtained with the hydrolysis reaction order of 1.615 and the rate constants being 0.0017, 0.0045 and 0.0097 at 220℃, 240℃ and 260℃ respectively. The activation energy is 145.1 kJ·mol^- 1. 展开更多
关键词 BIOMASS subcritical water HYDROLYSIS reaction kinetics amino acids
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Axisymmetric fundamental solutions for a finite layer with impeded boundaries 被引量:2
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作者 程泽海 陈云敏 +1 位作者 凌道盛 唐晓武 《Journal of Zhejiang University Science》 EI CSCD 2003年第4期393-399,共7页
Axisymmetric fundamental solutions that are applied in the consolidation calculations of a finite clay layer with impeded boundaries were derived. Laplace and Hankel integral transforms were utilized with respect to t... Axisymmetric fundamental solutions that are applied in the consolidation calculations of a finite clay layer with impeded boundaries were derived. Laplace and Hankel integral transforms were utilized with respect to time and radial coordinates, respectively in the analysis. The derivation of fundamental solutions considers two boundary value problems involving unit point loading and ring loading in the vertical. The solutions are extended to circular distributed and strip distributed normal load. The computation and analysis of settlements, vertical total stress and excess pore pressure in the consolidation layer subject to circular loading are presented. 展开更多
关键词 CONSOLIDATION Integral transform Finite layer Impeded boundaries
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