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有阻隔情况下土地定级因素因子作用分值算法研究 被引量:4
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作者 林先成 周介铭 《四川师范大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第1期102-107,共6页
城镇土地定级中定级因素因子作用分值计算难度较大、情况复杂、计算量大,特别是有阻隔存在情况下更是如此.作用分值计算直接影响定级成果的精度.以达州市城市土地定级为例,讨论栅格数据空间分析方法在定级因素作用分值计算中的应用.结... 城镇土地定级中定级因素因子作用分值计算难度较大、情况复杂、计算量大,特别是有阻隔存在情况下更是如此.作用分值计算直接影响定级成果的精度.以达州市城市土地定级为例,讨论栅格数据空间分析方法在定级因素作用分值计算中的应用.结果表明,栅格数据空间分析方法可以用于计算定级要素作用分值;特别在有阻隔存在的情况下,能够提高定级效率和定级成果的精度. 展开更多
关键词 阻隔 定级因素 作用分计算 栅格数据空间
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A simplified approach for settlement calculation of pile groups considering pile-to-pile interaction in layered soils 被引量:5
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作者 杨明辉 张小威 赵明华 《Journal of Central South University》 SCIE EI CAS 2011年第6期2131-2136,共6页
A simplified approach is presented for the analysis of the settlement of vertically loaded pile groups. In order to simulate the nonlinear pile-to-pile interaction in pile groups, the soils along the piles are assumed... A simplified approach is presented for the analysis of the settlement of vertically loaded pile groups. In order to simulate the nonlinear pile-to-pile interaction in pile groups, the soils along the piles are assumed to behave as a series of nonlinear springs subjected to the shaft shear stress at the pile/soil interface. Considering the displacement reduction induced by the pile-to-pile interaction, the shear-deformation method is adopted to approximate the displacement field of the layered soils around the piles, and the equivalent stiffness of the springs is obtained. Furthermore, the load-settlement response of pile groups is deduced by modifying the load-transfer functions to account for the pile-to-pile interaction. The settlements of a laboratory pile groups computed by the presented approach are in a good agreement with measured results. The analysis on Contrastive parameters shows that the settlements of pile group decrease with the increase of the pile space and pile length, and the part of piles exceeding the critical pile length has little contribution to the beating capacity of the pile groups. 展开更多
关键词 pile groups SETTLEMENT pile-to-pile interaction load transfer shear-deformation method
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Diffraction of Oblique Water Waves by Small Uneven Channel-bed in a Two-layer Fluid
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作者 Smrutiranjan Mohapatra 《Journal of Marine Science and Application》 2014年第3期255-264,共10页
Obliquely incident water wave scattering by an uneven channel-bed in the form of a small bottom undulation in a two-layer fluid is investigated within the frame work of three-dimensional linear water wave theory. The ... Obliquely incident water wave scattering by an uneven channel-bed in the form of a small bottom undulation in a two-layer fluid is investigated within the frame work of three-dimensional linear water wave theory. The upper fluid is assumed to be bounded above by a rigid lid, while the lower one is bounded below by a bottom surface having a small deformation and the channel is unbounded in the horizontal directions. Assuming irrotational motion, perturbation technique is employed to calculate the first-order corrections to the velocity potentials in the two fluids by using Fourier transform approximately, and also to calculate the reflection and transmission coefficients in terms of integrals involving the shape function representing the bottom deformation. Consideration of a patch of sinusoidal ripples shows that the reflection coefficient is an oscillatory function of the ratio of twice the component of the wave number along x-axis and the ripple wave number. When this ratio approaches one, the theory predicts a resonant interaction between the bed and interface, and the reflection coefficient becomes a multiple of the number of ripples. High reflection of incident wave energy occurs if this number is large. 展开更多
关键词 oblique waves two-layer fluid bottom undulation linear water wave theory reflection coefficient transmission coefficient perturbation technique Fourier transform
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Limit equilibrium stability analysis of slopes under external loads 被引量:4
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作者 DENG Dong-ping ZHAO Lian-heng LI Liang 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2382-2396,共15页
Two calculation modes for the effect of external load on slope stability, i.e., mode I in which the external load is thought to act on slope surface, and mode II in which the external load is thought to act on slip su... Two calculation modes for the effect of external load on slope stability, i.e., mode I in which the external load is thought to act on slope surface, and mode II in which the external load is thought to act on slip surface along the force action line, were considered. Meanwhile, four basic distribution patterns of external load were used, of which complex external loads could be composed. In analysis process, several limit equilibrium methods, such as Swedish method, simplified Bishop method, simplified Janbu method, Spencer method, Morgenstern-Price(M-P) method, Sarma method, and unbalanced thrust method, were also adopted to contrast their differences in slope stability under the external load. According to parametric analysis, some conclusions can be obtained as follows:(1) The external load, with the large magnitude, small inclination angle, and acting position close to the slope toe,has more positive effect on slope stability;(2) The results calculated using modes I and II of external load are similar, indicating that the calculation mode of external load has little influence on slope stability;(3) If different patterns of external loads are equivalent to each other, their slope stability under these external loads are the same, and if not, the external load leads to the better slope stability,as action position of the resultant force for external load is closer to the lower sliding point of slip surface. 展开更多
关键词 slope stability calculation mode of external load distribution pattern of external load limit equilibrium slip surface factor of safety (FOS)
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AIM Study on the Reaction of CH2SH Radical with Fluorine Atom
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作者 Cui-hong Suna Yan-li Zeng +1 位作者 Ling-peng Meng Shi-jun Zheng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第2期123-130,共8页
The reaction of CH2SH radical with fluorine atom was studied at the levels of B3LYP/6-311G(d,p) and MP2(Full)/6-311G(d,p). The computational results show that the reaction has three channels and proceeds by the ... The reaction of CH2SH radical with fluorine atom was studied at the levels of B3LYP/6-311G(d,p) and MP2(Full)/6-311G(d,p). The computational results show that the reaction has three channels and proceeds by the addition of fluorine atoms on carbon or sulfur sites of CH2SH, forming initial intermediates. The calculated results show that the channel, in which fluorine attaches to the carbon atom to form CH2S and HF, is the most likely reaction pathway. Topological analysis of electron density was carried out for the three channels. The change trends of the chemical bonds on the reaction paths were discussed. The energy transition states and the structure transition regions (states) of the three channels were found. The calculated results show that the structure transition regions are broad in unobvious exothermic reactions or unobvious endothermic reactions, and are narrow in obvious exothermic reactions or obvious endothermic reactions. 展开更多
关键词 Radical reaction Energy transition state Structure transition state Structure transition region Topological analysis of electronic density
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Limit analysis of vertical anti-pulling screw pile group under inclined loading on 3D elastic-plastic finite element strength reduction method 被引量:11
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作者 董天文 郑颖人 《Journal of Central South University》 SCIE EI CAS 2014年第3期1165-1175,共11页
Based on the functional theory, catastrophe theory, simultaneity principle and the idea of strength reduction method (SRM), the bearing capacity functional anti SRM of pile group foundation were established, and the... Based on the functional theory, catastrophe theory, simultaneity principle and the idea of strength reduction method (SRM), the bearing capacity functional anti SRM of pile group foundation were established, and the criteria of ultimate load and the concept of safety storage coefficient (Css) were advanced. The inclined ultimate loads by the static loading test, load increment method (LIM) and SRM are compared. Theoretically, the ultimate load of piles does not change with the loading levels when it is calculated by SRM. When the one strength reduction parameter is applied in the calculation boundary, there are calculating errors because the bearing capacity action of soils happened in the finite zone. The inclined 10adings are 108, 132 and 144 kN, and SSC are 1.07, 0.94 and 0.79, respectively, so the calculation values of ultimate loads are about 115.56, 124.08 and 113.76 kN, respectively. The error between calculations and observation values is less than 6%. But .the error between calculations of LIM and observations is 20%. Because of the effect of inclined loading, the push-rotation phenomenon of screw pile group appears. Under this testing, the ultimate bearing capacity of piles is mostly determined by the horizontal ultimate bearing capacity, and the effect of the vertical component of inclined load should also be considered. 展开更多
关键词 strength reduction method screw pile group ultimate load inclined loading
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Two-dimensional Numerical Simulation of an Elastic Wedge Water Entry by a Coupled FDM-FEM Method
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作者 Kangping Liao Changhong Hu Wenyang Duan 《Journal of Marine Science and Application》 2013年第2期163-169,共7页
Hydroelastic behavior of an elastic wedge impacting on calm water surface was investigated. A partitioned approach by coupling finite difference method (FDM) and finite element method (FEM) was developed to analyz... Hydroelastic behavior of an elastic wedge impacting on calm water surface was investigated. A partitioned approach by coupling finite difference method (FDM) and finite element method (FEM) was developed to analyze the fluid structure interaction (FSI) problem. The FDM, in which the Constraint Interpolation Profile (CIP) method was applied, was used for solving the flow field in a fixed regular Cartesian grid system. Free surface was captured by the Tangent of Hyperbola for Interface Capturing with Slope Weighting (THINC/SW) scheme. The FEM was applied for calculating the structural deformation. A volume weighted method, which was based on the immersed boundary (IB) method, was adopted for coupling the FDM and the FEM together. An elastic wedge water entry problem was calculated by the coupled FDM-FEM method. Also a comparison between the current numerical results and the published results indicate that the coupled FDM-FEM method has reasonably good accuracy in predicting the impact force. 展开更多
关键词 elastic wedge water entry coupled FDM-FEM method volume weighted method CIP method THINC/SW scheme hydroelastic behavior
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A Study on Control of Interconnection Inverter with FRT and Islanding Detection Functions
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作者 Shoji Kawasaki Masahiro Ise 《Journal of Energy and Power Engineering》 2018年第1期26-34,共9页
In this study, the authors aim to develop the interconnection inverter ofPV (photovoltaic generation) system with FRT (fault ride thorough) function and islanding detection function, and analyze the interaction be... In this study, the authors aim to develop the interconnection inverter ofPV (photovoltaic generation) system with FRT (fault ride thorough) function and islanding detection function, and analyze the interaction between the both functions during the momentary voltage drop by using an analytical model of distribution system interconnected plural PV systems. Moreover, the authors propose a cooperated control method of the inverters ~vith the islanding detection function and FRT function, and carry out a numerical calculation in order to verify the validity of the proposed method. 展开更多
关键词 Interconnection inverter ISLANDING islanding detection function momentary voltage drop FRT function.
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Calculation of interaction of AlCl, AlCl_2 and AlCl_3 on Al_4C_3(001) Al_4CO_4(001) and Al_2CO(001) planes
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作者 段少飞 陈秀敏 +3 位作者 杨斌 郁青春 徐宝强 刘大春 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期43-58,共16页
To make sure the intermediate products of the carbothermic reduction of Al2O3 process, such as Al4CO4, Al2CO and Al4C3,and the interaction of AlCl, AlCl2, AlCl3 with Al4CO4, Al2CO and Al4C3, respectively, thermodynami... To make sure the intermediate products of the carbothermic reduction of Al2O3 process, such as Al4CO4, Al2CO and Al4C3,and the interaction of AlCl, AlCl2, AlCl3 with Al4CO4, Al2CO and Al4C3, respectively, thermodynamic analyses were used to study the chloride reaction production of them under the vacuum situation. The stable structures and electronic properties of AlCl, AlCl2 and AlCl3 adsorbed on Al4CO4, Al2CO and Al4C3 were calculated by first-principles calculations by the CASTEP module in the Materials Studio program. The results show that the AlCl3 and AlCl2 molecules have decomposed on the plane of Al4C3(001), while there are no obvious decomposition of AlCl3 and AlCl2 on Al4CO4(001) and Al2CO(001) planes. The adsorption of AlCl on the Al4CO4(001)and Al2CO(001) planes is stronger than that on the Al4C3(001) plane. The interaction strength of AlCl3, as well as AlCl2, with Al4CO4,Al2CO and Al4C3 is in the sequence of Al4CO4Al2CO〉Al4C3. 展开更多
关键词 Ab initio chloride reaction carbothermic reduction Al4C3 Al4CO4 Al2CO
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Homogeneous label-free fluorescent assay of small molecule-protein interactions using protein binding-inhibited transcription nanomachine 被引量:4
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作者 ZHOU DianMing, WU YiDan, LIU Pei, BAI HaoTian, TANG LiJuan, YU RuQin & JIANG JianHui State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China 《Science China Chemistry》 SCIE EI CAS 2011年第8期1277-1283,共7页
Quantitative analysis of interactions between small molecules and proteins is a central challenge in chemical genetics, molecular diagnostics and drug developments. Here, we developed a RNA transcription nanomachine b... Quantitative analysis of interactions between small molecules and proteins is a central challenge in chemical genetics, molecular diagnostics and drug developments. Here, we developed a RNA transcription nanomachine by assembling T7 RNA polymerase on a small molecule-labeled DNA heteroduplex. The nanomachine, of which the RNA transcription activity can be quantitatively inhibited by protein binding, showed a great potential for small molecule-protein interaction assay. This finding enabled us to develop a novel homogeneous label-free strategy for assays of interactions between small molecules and their protein receptors. Three small molecule compounds and their protein receptors have been used to demonstrate the developed strategy. The results revealed that the protein-small molecule interaction assay strategy shows dynamic responses in the concentration range from 0.5 to 64 nM with a detection limit of 0.2 nM. Due to its label-free, homogeneous, and fluorescence-based detection format, besides its desirable sensitivity this technique could be greatly robust, cost-efficient and readily automated, implying that the developed small molecule-protein interaction assay strategy might create a new methodology for developing intrinsically robust, sensitive and selective platforms for homogeneous protein detection. 展开更多
关键词 nanomachine small molecule-linked DNA T7 RNA polymerase RNA transcription small molecule-protein interaction malachite green aptamer
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A flexible various-scale approach for soil-structure interaction and its application in seismic damage analysis of the underground structure of nuclear power plants 被引量:5
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作者 QU YongQian ZOU DeGao +2 位作者 KONG XianJing XU Bin YU Xiang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第7期1092-1106,共15页
In simulations of geotechnical engineering, interface elements are versatile tools and are widely used in the modeling of the relative displacements between soils and structures. To consider the case of a local failur... In simulations of geotechnical engineering, interface elements are versatile tools and are widely used in the modeling of the relative displacements between soils and structures. To consider the case of a local failure adjacent to a soil-structure interaction region, a partial mesh refinement should be performed. In this study, a three-dimensional(3 D) interface element with an arbitrary number of nodes is developed as a new technique to reduce the complexity and difficulty of managing the various scales between soil and structure. An asymmetric number of nodes is permissible on the two sliding surfaces. In this manner, soil and structure can be discretized independently, and the various-scale model is established conveniently and rapidly. The accuracy of the proposed method is demonstrated through numerical examples. The various-scale approach is employed in an elasto-plastic seismic damage analysis of a buried concrete drainage culvert of a nuclear power plant. The results indicate that by applying the proposed method, the number of elements decreased by 72.5%, and the computational efficiency improved by 59% with little influence on accuracy. The proposed method is powerful for local damage evolution analyses of both soil and structure and possesses great practical significance and the potential for further application, especially for nonlinear analysis of large-scale geotechnical engineering. 展开更多
关键词 3D interface element soil-structure interaction various-scale underground structure elasto-plastic analysis seismicdamage
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Multiple multicontrol unitary operations: Implementation and applications
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作者 Qing Lin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2018年第4期44-53,共10页
The efficient implementation of computational tasks is critical to quantum computations. In quantum circuits, multicontrol unitary operations are important components. Here, we present an extremely efficient and direc... The efficient implementation of computational tasks is critical to quantum computations. In quantum circuits, multicontrol unitary operations are important components. Here, we present an extremely efficient and direct approach to multiple multicontrol unitary operations without decomposition to CNOT and single-photon gates. With the proposed approach, the necessary twophoton operations could be reduced from O(n^3) with the traditional decomposition approach to O(n), which will greatly relax the requirements and make large-scale quantum computation feasible. Moreover, we propose the potential application to the(n-k)-uniform hypergraph state. 展开更多
关键词 multicontrol unitary operation cross phase modulation c-path gate merging gate hypergraph state
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