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各种各样的“开”法
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作者 乐伟国 《英语辅导(初一年级)》 2003年第2期3-3,共1页
1.Would you open the door?清你开门好吗?2.Let's turn on the TV and watch it together.我们打开电视机一起看吧!3.Mr Wang drives his car to work.王先生开小汽车上班。4.Who can fly a plane?谁会开飞机?
关键词 “开”法 初中 英语 教学
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艾儒棣教授运用“开鬼门”法治疗皮肤病经验 被引量:5
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作者 周林 陈娟 +1 位作者 朱霞俊 艾儒棣 《内蒙古中医药》 2021年第1期89-90,共2页
皮肤病的发生与皮肤毛窍闭塞休戚相关,运用发汗开窍的"开鬼门"法治疗皮肤病有重要意义。从上述两方面论述了艾教授重视发汗开窍法的缘由,并介绍常用药及临床应用案例。
关键词 皮肤病 “开鬼门”法 中医药疗 经验 艾儒棣教授
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Band Structure of Three-dimensional Phononic Crystals 被引量:3
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作者 颜琳 赵鹤平 +2 位作者 王小云 黄国盛 彭秀艳 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期155-158,共4页
By using the plane-wave-expansion method, the band structure of three-dimension phononic crystals was calculated, in which the cuboid scatterers were arranged in a host with a face-centered-cubic (FCC) structure.The... By using the plane-wave-expansion method, the band structure of three-dimension phononic crystals was calculated, in which the cuboid scatterers were arranged in a host with a face-centered-cubic (FCC) structure.The influences of a few factors such as the component materials, the filling fraction of scatterers and the ratio (RHL) of the scatterer's height to its length on the band-gaps of phononic crystals were investigated.It is found that in the three-dimension solid phononic crystals with FCC structure, the optimum case to obtain band-gaps is to embed high-velocity and high-density scatterers in a low-velocity and low-density host. The maximum value of band-gap can be obtained when the filling fraction is in the middle value. It is also found that the symmetry of the scatterers strongly influences the band-gaps. For RHL>1, the width of the band-gap decreases as RHL increases. On the contrary, the width of the band-gap increases with the increase of RHL when RHL is smaller than 1. 展开更多
关键词 Phononic crystals Band-gap Face-centered-cubic (FCC) Plane wave expansion method
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A model for extracting large deformation mining subsidence using D-InSAR technique and probability integral method 被引量:22
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作者 范洪冬 顾伟 +2 位作者 秦勇 薛继群 陈炳乾 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1242-1247,共6页
Due to the difficulties in obtaining large deformation mining subsidence using differential Interferometric Synthetic Aperture Radar (D-InSAR) alone, a new algorithm was proposed to extract large deformation mining ... Due to the difficulties in obtaining large deformation mining subsidence using differential Interferometric Synthetic Aperture Radar (D-InSAR) alone, a new algorithm was proposed to extract large deformation mining subsidence using D-InSAR technique and probability integral method. The details of the algorithm are as follows:the control points set, containing correct phase unwrapping points on the subsidence basin edge generated by D-InSAR and several observation points (near the maximum subsidence and inflection points), was established at first; genetic algorithm (GA) was then used to optimize the parameters of probability integral method; at last, the surface subsidence was deduced according to the optimum parameters. The results of the experiment in Huaibei mining area, China, show that the presented method can generate the correct mining subsidence basin with a few surface observations, and the relative error of maximum subsidence point is about 8.3%, which is much better than that of conventional D-InSAR (relative error is 68.0%). 展开更多
关键词 D-INSAR genetic algorithm probability integral method mining subsidence
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醒脑开窍针法对非痴呆性血管认知障碍的影响 被引量:22
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作者 张任 荣兵 +1 位作者 李建 李欣同 《中医杂志》 CSCD 北大核心 2019年第12期1046-1050,共5页
目的观察醒脑开窍针法治疗非痴呆性血管认知障碍(VCIND)的疗效并探讨其可能的作用机制。方法82例VCIND患者基于Zelen’s设计分为针刺组46例和西药组36例,两组患者均给予口服拜阿司匹林肠溶片、阿托伐他汀钙片作为基础治疗;西药组加用口... 目的观察醒脑开窍针法治疗非痴呆性血管认知障碍(VCIND)的疗效并探讨其可能的作用机制。方法82例VCIND患者基于Zelen’s设计分为针刺组46例和西药组36例,两组患者均给予口服拜阿司匹林肠溶片、阿托伐他汀钙片作为基础治疗;西药组加用口服盐酸多奈哌齐片5 mg,每日1次;针刺组加用醒脑开窍针法治疗,每日2次,每周6天,两组均治疗8周。治疗前及治疗4、8周后评价两组患者蒙特利尔认知评估量表(MoCA)、日常生活能力量表(ADL)评分结果,并观察血清降钙素基因相关肽(CGRP)、淀粉蛋白前β位分解酶1(BACE1)及其mRNA水平。治疗4、8周后评价临床疗效。结果针刺组治疗4、8周后总有效率分别为64.86%(24/37)、89.19%(33/37),均高于西药组的54.84%(17/31)、80.65%(25/31)(P<0.05)。两组患者治疗4、8周后MoCA、ADL评分均较治疗前显著改善,且针刺组优于西药组(P<0.05)。两组患者治疗4、8周后血清CGRP及其mRNA均升高,BACE1及其mRNA均降低,且针刺组治疗4、8周改善均优于西药组(P<0.05)。结论醒脑开窍针法可显著改善VCIND患者临床症状,其机制可能涉及调节神经中枢血管舒张因子CGRP和神经元损害蛋白标志物BACE1表达。 展开更多
关键词 非痴呆性血管认知障碍 醒脑窍针 认知能力 血清降钙素基因相关肽 淀粉蛋白前β位分解酶1
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《明史》商屯臆想补论 被引量:5
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作者 罗冬阳 《史学集刊》 CSSCI 北大核心 2019年第3期34-42,共9页
《明史·食货志》将明前期开中法等同于商屯的主张,影响深远,但究其根据,实是未做任何直接论证的臆想。洪永年间,开中法在九边未曾持续稳定展开,且禁止收购本地粮食用于开中,盐业资源亦未尝全部用于九边开中,商屯土地产权也无保障... 《明史·食货志》将明前期开中法等同于商屯的主张,影响深远,但究其根据,实是未做任何直接论证的臆想。洪永年间,开中法在九边未曾持续稳定展开,且禁止收购本地粮食用于开中,盐业资源亦未尝全部用于九边开中,商屯土地产权也无保障。尽管宣德正统以后开中全面展开,但九边军事—经济社会名义上国有,实际上边将和权贵私自占有。在盐粮开中的刺激下,无法为外来客商发展商屯提供必要条件,反而为边将和权贵私役军士开垦土地提供了强大激励。 展开更多
关键词 明史食货志 商屯
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Landscape Design Methods of Urban Sponge Park 被引量:2
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作者 陈晓刚 朱智 杨昆 《Agricultural Science & Technology》 CAS 2016年第4期938-941,共4页
Urban rain-caused floods can not be well resolved with rising urban problem. Hence, construction of sponge park is born at the right moment. The research reviewed the concept, content and value of sponge parks and pro... Urban rain-caused floods can not be well resolved with rising urban problem. Hence, construction of sponge park is born at the right moment. The research reviewed the concept, content and value of sponge parks and proposed theory and principle of landscape design in order to seek the method of landscape design of sponge parks, improve urban eco-environment and advance harmony development between human and nature. 展开更多
关键词 Sponge park Low impact development Design method
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Exploration of Methods for Preparation of Cattle Eyeball Paraffin Sections 被引量:1
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作者 邓立新 郭延俭 +4 位作者 王绿林 王朝阳 董海聚 李杨 贺丛 《Agricultural Science & Technology》 CAS 2014年第1期71-73,共3页
[Objective] This study aimed to establish a new method for preparing paraffin sections of cattle eyebal s. [Method] The conventional method was used to prepare paraffin sections for cattle eyebal s in the control and ... [Objective] This study aimed to establish a new method for preparing paraffin sections of cattle eyebal s. [Method] The conventional method was used to prepare paraffin sections for cattle eyebal s in the control and a new method termed&quot;opening a window on cornea and refixation&quot; was used to prepare paraffin sections for cattle eyebal s in the treatment group. [Result] After the prepared specimens in the treatment group were fixed, it could be macroscopical y observed that retina and choroid were closely connected, with detachment occurring at a smal portion be-tween the two. According to the paraffin sections, it was microscopical y observed that the continuity of trabecular meshwork was intact, as wel as the continuity be-tween different layers of eyebal wal , without detachment between them, no retinal detachment, no shrinkage of each layer of tissue cells. [Conclusion] This study pro-vides a foundation for the basic research and pathological study of eyebal s. 展开更多
关键词 CATTLE EYEBALL Paraffin sections "Opening a window on cornea andrefixation" method
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Calculation of Valence Subband Structures for Strained Quantum-Wells by Plane Wave Expansion Method Within 6×6 Luttinger-Kohn Model
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作者 国伟华 黄永箴 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第6期577-581,共5页
The valence subband energies and wave functions of a tensile strained quantum well are calculated by the plane wave expansion method within the 6×6 Luttinger Kohn model.The effect of the number and period of pla... The valence subband energies and wave functions of a tensile strained quantum well are calculated by the plane wave expansion method within the 6×6 Luttinger Kohn model.The effect of the number and period of plane waves used for expansion on the stability of energy eigenvalues is examined.For practical calculation,it should choose the period large sufficiently to ensure the envelope functions vanish at the boundary and the number of plane waves large enough to ensure the energy eigenvalues keep unchanged within a prescribed range. 展开更多
关键词 semiconductor optical amplifier strained quantum well plane wave expansion method POLARIZATION
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Three-dimensional orebody modelling and intellectualized longwall mining for stratiform bauxite deposits 被引量:4
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作者 王少锋 李夕兵 +4 位作者 王善勇 李启月 陈冲 冯帆 陈英 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第10期2724-2730,共7页
Acoupled biharmonic spline and linear interpolation algorithm was proposed to create a three-dimensional smooth deposit model with minimal curvature containing grade and position data. To obtain the optimal technical ... Acoupled biharmonic spline and linear interpolation algorithm was proposed to create a three-dimensional smooth deposit model with minimal curvature containing grade and position data. To obtain the optimal technical parameters, such as cuttingheight and drum diameter, a virtual longwall mining procedure was modelled by simulating the actual fully mechanized longwall mining process. Based on the above work, a bauxite deposit in a longwall mining panel was modelled by scattered grade data from ores sampled on the entry wall. The deposit was then demarcated by industrial indexes and sliced according to the virtual longwallmining procedure. The results show that the proposed interpolation algorithm can depict the stratiform structure of bauxite depositsand that the uncovered bauxite deposit has high proportions of high-grade and rich ore. The ranges of optimal cutting height and drum diameters are 1.72-2.84 m and 1.42-1.72 m, respectively. Finally, an intellectualized longwall mining procedure was designed to guide the mining process with the lowest dilution and loss rates. 展开更多
关键词 stratiform bauxite deposit orebodymodelling interpolation algorithm virtual longwall mining cutting height drum diameter
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A General Study of the Number of Assembly Configurations for Multi-Circuit Planar Linkages
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作者 杭鲁滨 金琼 +1 位作者 吴俊 杨廷力 《Journal of Southeast University(English Edition)》 EI CAS 2000年第1期46-51,共6页
This paper presents a general approach for determining the configuration number for any linkage: A kinematic cham (KC) can be divided into some basic kinematic chains (BKCs) and driving joints; there are only 33 kinds... This paper presents a general approach for determining the configuration number for any linkage: A kinematic cham (KC) can be divided into some basic kinematic chains (BKCs) and driving joints; there are only 33 kinds of BKCs with υ =1-4 independent loop, containing only R (revolute) joints and their configuration numbers are given; the configuration number of a KC equals to the multiplication of the configuration numbers of BKCs contained in the KC. 展开更多
关键词 basic kinematic chain configuration number homotopy method
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Nonlinear Auto-Companding Method for Behavioral Modeling of Switched-Current Circuits
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作者 王伟 曾璇 +2 位作者 陶俊 苏仰峰 唐璞山 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第12期1254-1261,共8页
A wavelet collocation method with nonlinear auto companding is proposed for behavioral modeling of switched current circuits.The companding function is automatically constructed according to the initial error distri... A wavelet collocation method with nonlinear auto companding is proposed for behavioral modeling of switched current circuits.The companding function is automatically constructed according to the initial error distribution obtained through approximating the input output function of the SI circuit by conventional wavelet collocation method.In practical applications,the proposed method is a general purpose approach,by which both the small signal effect and the large signal effect are modeled in a unified formulation to ease the process of modeling and simulation.Compared with the published modeling approaches,the proposed nonlinear auto companding method works more efficiently not only in controlling the error distribution but also in reducing the modeling errors.To demonstrate the promising features of the proposed method,several SI circuits are employed as examples to be modeled and simulated. 展开更多
关键词 wavelet collocation method behavioral modeling switched current circuits nonlinear auto companding
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Similar material simulation of time series system for induced caving of roof in continuous mining under backfill 被引量:9
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作者 高峰 周科平 +1 位作者 董卫军 苏家红 《Journal of Central South University of Technology》 EI 2008年第3期356-360,共5页
With the help of similar material simulation test,time series system for induced caving of roof in continuous mining under complex backfill in ore body No.92 of Tongkeng Tin Mine was studied. According to the similari... With the help of similar material simulation test,time series system for induced caving of roof in continuous mining under complex backfill in ore body No.92 of Tongkeng Tin Mine was studied. According to the similarity theory,a two-dimensional similar simulation test-bed was constructed. The stress and displacement that change along with the advance of mining were acquired and analyzed automatically by data system. The processes of continuous mining of ore-block in 5 intervals and artificial induced caving of roof were simulated. The results of the test show that ore body remained as safety roof in thickness of 15 m guarantees the safe advance of stoping work face. Caving of safety roof puts in practice at the first two mining intervals when the third interval of continuous mining is finished,and one interval as the safety distance should be kept all the time between stopping and caving. While mining in the last interval,pre-slotting should be implemented first of all,and the roof of the last two mining intervals is caved simultaneously. Only this kind of time series system can be an efficient and safe way for induced caving of roof in continuous mining. 展开更多
关键词 continuous mining induced caving similar material simulation safety roof SLOTTING
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Application of Modified G'/G-Expansion Method to Traveling Wave Solutions for Whitham-Broer-Kaup-Like Equations 被引量:5
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作者 ZHOU Yu-Bin LI Chao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期664-670,共7页
A modified G′/G-expansion method is presented to derive traveling wave solutions for a class of nonlinear partial differential equations called Whitham -Broer- Kaup-Like equations. As a result, the hyperbolic functio... A modified G′/G-expansion method is presented to derive traveling wave solutions for a class of nonlinear partial differential equations called Whitham -Broer- Kaup-Like equations. As a result, the hyperbolic function solutions, trigonometric function solutions, and rational solutions with parameters to the equations are obtained. When the parameters are taken as special values the solitary wave solutions can be obtained. 展开更多
关键词 Whitham-Brover-Kaup-like equations G′/G-expansion solitary wave solution
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Double Symplectic Eigenfunction Expansion Method of Free Vibration of Rectangular Thin Plates 被引量:7
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作者 WANG Hua Alatancang HUANG Jun-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期1087-1092,共6页
The free vibration problem of rectangular thin plates is rewritten as a new upper triangular matrix differential system. For the associated operator matrix, we find that the two diagonal block operators are Hamiltonia... The free vibration problem of rectangular thin plates is rewritten as a new upper triangular matrix differential system. For the associated operator matrix, we find that the two diagonal block operators are Hamiltonian. Moreover, the existence and completeness of normed symplectic orthogonal eigenfunction systems of these two block operators are demonstrated. Based on the completeness, the general solution of the free vibration of rectangular thin plates is given by double symplectie eigenfunction expansion method. 展开更多
关键词 free vibration of rectangular thin plate double symplectic eigenfunction expansion method upper triangular matrix differential system general solution
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Optimized SHA-1 hash function implemented on FPGA 被引量:2
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作者 薛也 胡爱群 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期13-16,共4页
In order to meet the needs of higher operation speed and lower energy consumption an optimized SHA-1 algorithm is proposed.It combines two methods loop-unfolding and pre-processing.In the process intermediate variable... In order to meet the needs of higher operation speed and lower energy consumption an optimized SHA-1 algorithm is proposed.It combines two methods loop-unfolding and pre-processing.In the process intermediate variables are introduced in the iterations and pre-calculated so that the original single-threading operation can perform in a multi-threading way.This optimized algorithm exploits parallelism to shorten the critical path for hash operations.And the cycles of the original algorithm are reduced from 80 to 41 which greatly improves the operation speed.Therefore the shortened iterations of the optimized design require a smaller amount of hardware resource thus achieving a lower energy consumption. The optimized algorithm is implemented on FPGA field programmable gate array .It can achieve a throughput rate of 1.2 Gbit /s with the maximum clock frequency of 91 MHz reaching a fair balance between operation speed and throughput rate.The simulation results show that compared with other optimized SHA-1 algorithms this algorithm obtains higher operation speed and throughput rate without compromising the security of the original SHA-1 algorithm. 展开更多
关键词 FPGA hash function loop unfolding pre-processing FPGA
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Characteristics of Gas Emission at Super-Length Fully-Mechanized Top Coal Caving Face 被引量:10
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作者 XU Jia-lin YU Bei-jian +1 位作者 LOU Jin-fu WANG Dong-ping 《Journal of China University of Mining and Technology》 EI 2007年第4期447-452,共6页
Characteristics of gas emission at the K8206 working face in the Third mine of the Yangquan Coal Group were investigated. The effects of strata movement,advancing velocity of working face,production capacity of workin... Characteristics of gas emission at the K8206 working face in the Third mine of the Yangquan Coal Group were investigated. The effects of strata movement,advancing velocity of working face,production capacity of working face and gas extraction capability of strike high-level entry on gas emission at K8206 working face were analyzed. A regression equation,reflecting the relationship between relative gas emission rate and the production capacity of work-ing faces,was established. Another regression equation showing the relationship between the gas emission rate from adjacent layers when the working face was advancing for one metre and advancing velocity was derived. It can be con-cluded that,1) the amount of gas emitted at the K8206 working face is far greater than that of ordinary top coal caving faces with a dip length of 180-190 m; 2) the dynamic process of gas emission from adjacent layers during the initial mining stage is controlled by the movement of key strata; 3) the amount of gas emitted that needs to be forced out by air is greatly affected by the capability of gas extraction; 4) when the advancing velocity is between 3.5-5.5 m/d or when the output is up to 8-12 kt/d,the gas emission from adjacent layers is almost constant. 展开更多
关键词 super-length fully-mechanized top coal caving face characteristics of gas emission strata movement
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A probe into“mining technique in the condition of floor failure”for coal seam above longwall goafs 被引量:4
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作者 冯国瑞 王鲜霞 康立勋 《Journal of Coal Science & Engineering(China)》 2008年第1期19-23,共5页
Targeting at the coal seam with useful value discarded above goafs,attempted to explore the feasibility of'mining technique in the condition of floor failure' from theoretical point of view,and predicted.It in... Targeting at the coal seam with useful value discarded above goafs,attempted to explore the feasibility of'mining technique in the condition of floor failure' from theoretical point of view,and predicted.It indicated that mining technique in the condition of floor failure used above Longwall Goafs in Baijiazhuang Mining is totally feasible.At law,the deformation of the floor in the mining technique by means of probability-integral method.And it is discov- ered that deformed basin can emerge in the footwall of No.6 coal seam and its maximum subsidence was possibly 1 633 mm or so and its maximum positive curvature is 61.74/10^(-3). At last,it therefore suggests appropriate ground pressure control measures as strengthening observation of ground pressure and adopting false slope for exploitation and strengthening support for reasonable push and slide based on the adverse ground pressure behaviors possibly occurring in the mining technique.This serves to gather data and lay sturdy founda- tion for further probe into the mining technique,and offers theoretical and technical grounds for concrete implementation of the mining technique. 展开更多
关键词 mining technique in the condition of floor failure Iongwall goafs probability-integral method
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Oblique Wave Motion over Multiple Submerged Porous Bars near a Vertical Wall 被引量:3
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作者 ZHAO Yang LIU Yong +1 位作者 LI Huajun CHANG Anteng 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第4期568-574,共7页
This study examines oblique wave motion over multiple submerged porous bars in front of a vertical wall. Based on linear potential theory, an analytical solution for the present problem is developed using matched eige... This study examines oblique wave motion over multiple submerged porous bars in front of a vertical wall. Based on linear potential theory, an analytical solution for the present problem is developed using matched eigenfunction expansions. A complex dispersion relation is adopted to describe the wave elevation and energy dissipation over submerged porous bars. In the analytical solution, no limitations on the bar number, bar size, and spacing between adjacent bars are set. The convergence of the analytical solution is satisfactory, and the correctness of the analytical solution is confirmed by an independently developed multi-domain BEM (boundary element method) solution. Numerical examples are presented to examine the reflection and transmission coefficients of porous bars, CR and Cv, respectively, for engineering applications. The calculation results show that when the sum of widths for all the porous bars is fixed, increasing the bar number can significantly improve the sheltering function of the bars. Increasing the bar height can cause more wave energy dissipation and lower CR and Cr. The spacing between adjacent bars and the spacing between the last bar and the vertical wall are the key parameters affecting CR and Ct. The proposed analytical method may be used to analyze the hydrodynamic performance of submerged porous bars in preliminary engineering designs. 展开更多
关键词 multiple porous bars oblique wave vertical wall reflection coefficient transmission coefficient
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Design of Stubble-breaking Ditching Colter Based on SolidWorks and Its Strength Analysis
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作者 何磊 周亚立 +1 位作者 刘向新 赵岩 《Agricultural Science & Technology》 CAS 2011年第10期1441-1443,1452,共4页
Stubble-breaking device is a key working part of no-tillage seeder in stub land,and directly affects planting quality of seeder.Based on the current domestic used stubble-breaking device,a new kind of stubble-breaking... Stubble-breaking device is a key working part of no-tillage seeder in stub land,and directly affects planting quality of seeder.Based on the current domestic used stubble-breaking device,a new kind of stubble-breaking ditching colter was designed.To study its strength property and reduce trouble in work,the three-dimensional model of stubble-breaking ditching colter was established based on SolidWorks.By using Cosmos,it was carried out the finite element analysis.The distortion and stress of stubble-breaking ditching colter in work were obtained,and the weak link of strength was found.The result showed that the maximum stress of stubble-breaking ditching colter was 5.862×108 N/m2,and the maximum twisted displacement was 2.648 mm.The stubble-breaking ditching colter was carried out improved design.Based on Cosmos,the static analysis was carried out.It showed that the strength and rigidity of improved stubble-breaking ditching colter were obviously improved.The research provided reference basis for optimal design of the stubble-breaking ditching colter. 展开更多
关键词 Stubble-breaking ditching colter No-tillage sowing Finite element analysis Static analysis
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