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Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
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作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order three-Point Boundary Value Problem Sign-Changing Green’s function Fixed Point Index Iterative Technique Monotone Positive Solution EXISTENCE
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Generalized thermoelastic interaction in functional graded material with fractional order three-phase lag heat transfer 被引量:3
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作者 Ibrahim A.Abbas 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1606-1613,共8页
The present work is concerned with the solution of a problem on thermoelastic interactions in a functional graded material due to thermal shock in the context of the fractional order three-phase lag model. The governi... The present work is concerned with the solution of a problem on thermoelastic interactions in a functional graded material due to thermal shock in the context of the fractional order three-phase lag model. The governing equations of fractional order generalized thermoelasticity with three-phase lag model for functionally graded materials(FGM)(i.e., material with spatially varying material properties) are established. The analytical solution in the transform domain is obtained by using the eigenvalue approach.The inversion of Laplace transform is done numerically. The graphical results indicate that the fractional parameter has significant effects on all the physical quantities. Thus, we can consider the theory of fractional order generalized thermoelasticity an improvement on studying elastic materials. 展开更多
关键词 three-phase lag model fimctionally graded materials fractional calculus generalized thermoelasticity
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Three-dimensional visualization of the functional fascicular groups of a long-segment peripheral nerve 被引量:3
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作者 Jian Qi Wei-Ya Wang +7 位作者 Ying-Chun Zhong Jia-Ming Zhou Peng Luo Ping Tang Cai-Feng He Shuang Zhu Xiao-Lin Liu Yi Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第8期1465-1470,共6页
The three-dimensional(3D) visualization of the functional bundles in the peripheral nerve provides direct and detailed intraneural spatial information. It is useful for selecting suitable surgical methods to repair ... The three-dimensional(3D) visualization of the functional bundles in the peripheral nerve provides direct and detailed intraneural spatial information. It is useful for selecting suitable surgical methods to repair nerve defects and in optimizing the construction of tissue-engineered nerve grafts. However, there remain major technical hurdles in obtaining, registering and interpreting 2D images, as well as in establishing 3D models. Moreover, the 3D models are plagued by poor accuracy and lack of detail and cannot completely reflect the stereoscopic microstructure inside the nerve. To explore and help resolve these key technical problems of 3D reconstruction, in the present study, we designed a novel method based on re-imaging techniques and computer image layer processing technology. A 20-cm ulnar nerve segment from the upper arm of a fresh adult cadaver was used for acetylcholinesterase(ACh E) staining. Then, 2D panoramic images were obtained before and after ACh E staining under the stereomicroscope. Using layer processing techniques in Photoshop, a space transformation method was used to fulfill automatic registration. The contours were outlined, and the 3D rendering of functional fascicular groups in the long-segment ulnar nerve was performed with Amira 4.1 software. The re-imaging technique based on layer processing in Photoshop produced an image that was detailed and accurate. The merging of images was accurate, and the whole procedure was simple and fast. The least square support vector machine was accurate, with an error rate of only 8.25%. The 3D reconstruction directly revealed changes in the fusion of different nerve functional fascicular groups. In conclusion. The technique is fast with satisfactory visual reconstruction. 展开更多
关键词 nerve regeneration peripheral nerve ulnar nerve three-dimensional reconstruction functional fascicular group REGISTRATION segmentation locating spots auto-registration ACETYLCHOLINESTERASE neural regeneration
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Three-dimensionally ordered macroporous cross-linked polystyrene incorporating functional group via hydrophilic spacer arm 被引量:1
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作者 Li Xia Yuan Xiao Mei Wang Xu Zhang Pan Ge Liu Wei Dong Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1493-1496,共4页
A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.Th... A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.The 3DOM CLPS with pore size 865 nm was prepared by sacrifice template method.The hydrophilic spacer arm(polyethylene glycol,molecular weight is 600) was grafted to the 3DOM CLPS via nucleophilic substitution reaction.The other side of active hydroxyl can be further converted into a lot of other functional groups.In this report,the chelating ligand 2-mercaptobenzothiazole(MBZ) group was introduced on the end of the PGE chain to evidence the versatile functionalization approach.The functionalized ordered macroporous materials were characterized by FT-IR,element analyzer,SEM.The results reveal that the pores were successfully bonded with 2-mercaptobenzothiazole groups via hydrophilic spacer arms and the original morphology of ordered macroporous materials were remained after functionalization.The MBZ group density is 0.052 mmol/m^2.The functionalized 3DOM CLPS are expected to application as heavy metal ions adsorbent. 展开更多
关键词 three-dimensionally ordered macroporous polymer functionALIZATION Hydrophilic space arm Heterocyclic functional group
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Meromorphic Functions Sharing Three Values
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作者 Changjun Li Limei Wang 《Applied Mathematics》 2011年第6期718-724,共7页
In this paper, we prove a result on the uniqueness of meromorphic functions sharing three values counting multiplicity and improve a result obtained by Xiaomin Li and Hongxun Yi.
关键词 UNIQUENESS MEROMORPHIC functions SHARING three VALUES
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Three-talk决策模式干预对急性脑梗死病人神经功能恢复和心理状态的影响
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作者 刘伟 倪木兰 《蚌埠医学院学报》 CAS 2024年第5期669-673,共5页
目的:探讨Three-talk决策模式干预对急性脑梗死病人神经功能恢复和心理状态的影响。方法:选取急性脑梗死病人80例,随机分为对照组和观察组,各40例。对照组给予常规护理,观察组在常规护理基础上给予Three-talk决策模式(包括团队会谈、选... 目的:探讨Three-talk决策模式干预对急性脑梗死病人神经功能恢复和心理状态的影响。方法:选取急性脑梗死病人80例,随机分为对照组和观察组,各40例。对照组给予常规护理,观察组在常规护理基础上给予Three-talk决策模式(包括团队会谈、选择会谈、决策会谈)干预,比较2组病人干预前和干预1个月后的负性情绪、肢体肌力、运动功能、吞咽功能和自我护理能力(ESEA)评分。结果:干预前,2组病人焦虑、抑郁、肢体肌力、运动功能、吞咽功能和ESEA评分差异均无统计学意义(P>0.05);干预1个月后,观察组焦虑、抑郁和吞咽功能评分均明显低于对照组(P<0.01),肢体肌力、运动功能、ESEA评分均明显高于对照组(P<0.01)。结论:Three-talk决策模式干预有助于缓解急性脑梗死病人的焦虑、抑郁情绪,帮助病人实现肢体肌力、运动及吞咽功能的恢复,进而提高其自我护理能力。 展开更多
关键词 急性脑梗死 three-talk决策模式 负性情绪 肢体肌力 运动功能
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THREE-DIMENSIONAL ANALYSIS OF FUNCTIONALLY GRADED PLATE BASED ON THE HAAR WAVELET METHOD 被引量:2
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作者 Zhang Chun Zhong Zheng 《Acta Mechanica Solida Sinica》 SCIE EI 2007年第2期95-102,共8页
A three-dimensional analysis of a simply-supported functionally graded rectangular plate with an arbitrary distribution of material properties is made using a simple and effective method based on the Haar wavelet. Wit... A three-dimensional analysis of a simply-supported functionally graded rectangular plate with an arbitrary distribution of material properties is made using a simple and effective method based on the Haar wavelet. With good features in treating singularities, Haar series solution converges rapidly for arbitrary distributions, especially for the case where the material properties change rapidly in some regions. Through numerical examples the influences of the ratio of material constants on the top and bottom surfaces and different material gradient distributions on the structural response of the plate to mechanical stimuli are studied. 展开更多
关键词 functionally graded material rectangular plate Haar wavelet three-dimensional analysis
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Study on Prediction Method of Structural Three-parameter Power Function P-S-N Curve
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作者 LIU Yujie DAI Zongmiao 《International Journal of Plant Engineering and Management》 2018年第2期65-70,共6页
This paper applies weighted least square method to estimate the three-parameter power function equation of the fatigue life curve, and uses comprehensive fatigue life coefficient to correct the equation, and at the sa... This paper applies weighted least square method to estimate the three-parameter power function equation of the fatigue life curve, and uses comprehensive fatigue life coefficient to correct the equation, and at the same time combines probability statistics method to bring out the prediction method of structure's three- parameter power function P-S-N curve, finally applies the prediction method to a ship's frame-type elevate, based on the fatigue test data of it's material-SA06 aluminium alloy, to obtain it's structure's three-parameter power function P-S-N curve. Compared with the conventional least square method, the presented method can give 展开更多
关键词 P-S-N curve comprehensive fatigue life coefficient three-parameter power function fatigue life
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Three-dimensional elasticity solutions for bending of generally supported thick functionally graded plates
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作者 张鹤 蒋吉清 张治成 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第11期1467-1478,共12页
Three-dimensional elasticity solutions for static bending of thick functionally graded plates are presented using a hybrid semi-analytical approach-the state-space based differential quadrature method (SSDQM). The p... Three-dimensional elasticity solutions for static bending of thick functionally graded plates are presented using a hybrid semi-analytical approach-the state-space based differential quadrature method (SSDQM). The plate is generally supported at four edges for which the two-way differential quadrature method is used to solve the in-plane variations of the stress and displacement fields numerically. An approximate laminate model (ALM) is exploited to reduce the inhomogeneous plate into a multi-layered laminate, thus applying the state space method to solve analytically in the thickness direction. Both the convergence properties of SSDQM and ALM are examined. The SSDQM is validated by comparing the numerical results with the exact solutions reported in the literature. As an example, the Mori-Tanaka model is used to predict the effective bulk and shear moduli. Effects of gradient index and aspect ratios on the bending behavior of functionally graded thick plates are investigated. 展开更多
关键词 functionally grade material thick plate three-dimensional solution semianalytical approach
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Preliminary Clinical Study of Real-time Three-dimensional Echo-cardiographic Volume-time Curve in Evaluating Left Ventricular Diastolic Function
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作者 费洪文 何亚乐 +3 位作者 侯跃双 许燕 黄新胜 冯碧霞 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第4期475-478,共4页
The volume-time curve change in patients with normal left ventricular (LV) diastolic function and diastolic dysfunction was evaluated by real-time three-dimensional echocardiography (RT3DE). LV diastolic dysfuncti... The volume-time curve change in patients with normal left ventricular (LV) diastolic function and diastolic dysfunction was evaluated by real-time three-dimensional echocardiography (RT3DE). LV diastolic dysfunction was defined by E'〈A' in pulse-wave tissue Doppler for inter-ventricular septal (IVS) of mitral annulus. In 24 patients with LV diastolic dysfunction, including 12 patients with delayed relaxation (delayed relaxation group) and 12 patients with pseudo-normal function (pseudo-normal group) and 24 normal volunteers (control group), data of full-volume image were acquired by real-time three-dimensional echocardiography and subjected to volume-time curve analysis. EDV (end-diastolic volume), ESV (end-systolic volume), LVEF (left ventricular ejection fraction), PER (peak ejection rate), PFR (peak filling rate) from RT3DE were examined in the three groups. Compared to the control group, PFR (diastolic filling index of RT3DE) was significantly reduced in the delayed relaxation group and pseudo-normal group (P〈0.05). There were no significant differences in EDV, ESV, LVEE PER (P〉0.05). It is concluded that PFR, as a diastolic filling index of RT3DE, can reflect the early diastolic function and serve as a new non-invasive, quick and accurate tool for clinical assessment of LV diastolic function. 展开更多
关键词 real-time three-dimensional echocardiography left ventricular diastolic function volume-time curve
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Three-dimensional Analysis of Functionally Graded Piezoelectric Plate with Arbitrarily Distributed Material Properties
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作者 刘五祥 MA Shaokun 吴昊 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第4期712-720,共9页
An orthotropic functionally graded piezoelectric rectangular plate with arbitrarily distributed material properties was studied, which is simply supported and grounded(electrically) on its four lateral edges. The st... An orthotropic functionally graded piezoelectric rectangular plate with arbitrarily distributed material properties was studied, which is simply supported and grounded(electrically) on its four lateral edges. The state equations of the functionally graded piezoelectric material were obtained using the state-space approach, and a Peano-Baker series solution was obtained for the coupled electroelastic fi elds of the functionally graded piezoelectric plate subjected to mechanical and electric loading on its upper and lower surfaces. The influence of different distributions of material properties on the structural response of the plate was studied using the obtained solutions. 展开更多
关键词 functionally graded piezoelectric materials peano-baker series three-dimensional analysis state-space approach
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MATLAB/Simulink S-function在三相异步电机教学中的应用研究 被引量:5
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作者 巫庆辉 崔总泽 李琳 《渤海大学学报(自然科学版)》 CAS 2011年第3期249-253,共5页
针对三相异步电动机教学过程中较深的理论知识不利于学生理解与掌握的问题,对MATLAB/Simulink S-function在三相异步电机教学进行了应用研究,MATLAB环境下Simulink与S-function有机结合搭建了三相异步电动机的仿真平台,仿真结果验证了... 针对三相异步电动机教学过程中较深的理论知识不利于学生理解与掌握的问题,对MATLAB/Simulink S-function在三相异步电机教学进行了应用研究,MATLAB环境下Simulink与S-function有机结合搭建了三相异步电动机的仿真平台,仿真结果验证了该方法的有效性。 展开更多
关键词 教学 MATLAB/SIMULINK S—function 电机与拖动 三相异步电动机
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基于三周期极小曲面晶胞梯度支架的设计及力学性能
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作者 朱文博 张旭婧 +1 位作者 许燕 石欣桐 《中国组织工程研究》 CAS 北大核心 2025年第16期3449-3457,共9页
背景:现阶段骨软骨一体化支架的弹性模量与天然骨软骨相差较大,植入人体后会引起应力遮蔽现象,从而导致植入物松动变形,影响骨软骨组织修复。轴向三周期极小曲面晶胞梯度支架可与人体骨软骨组织孔隙率及弹性模量相匹配,为骨软骨支架设... 背景:现阶段骨软骨一体化支架的弹性模量与天然骨软骨相差较大,植入人体后会引起应力遮蔽现象,从而导致植入物松动变形,影响骨软骨组织修复。轴向三周期极小曲面晶胞梯度支架可与人体骨软骨组织孔隙率及弹性模量相匹配,为骨软骨支架设计提供一种新的思路。目的:研究不同晶胞种类和孔径结构对晶胞梯度支架力学性能的影响。方法:使用Gyroid(G)型、Diamond(D)型Primitive(P)型3种基础晶胞,通过三周期极小曲面数学建模,在梯度区域使用不同尺寸、不同种类晶胞,共计构建6种晶胞梯度支架(G-2P-4D、P-2D-4G、D-2P-4D、G-2D-4P、P-2G-4D、D-2G-4P),进行力学实验及仿真模拟实验,评估支架的力学性能,通过计算流体动力学仿真得到了支架内流体的流动性能参数。结果与结论:有限元力学仿真和轴向压缩实验表明,P-2G-4D型与P-2D-4G型梯度支架的弹性模量相较高,分别为148.67 MPa和152.1 MPa,能够承受较高的轴向载荷,提高植入物的力学稳态;D-2P-4G型梯度支架应力分布最为均匀,可有效减少应力集中,使得连接函数区域均能够有效传递应力,减少应力遮蔽;G-2D-4P型梯度支架流动速率变化最小,为0.10-0.48 mm/s,渗透率较高,有利于植入后体液在支架内部流动。基于三周期极小曲面的晶胞梯度支架设计为骨软骨支架设计提供了新思路,仿真分析结果也为支架植入人体后的骨整合预测提供了参考。 展开更多
关键词 三周期极小曲面 晶胞梯度 连接函数 骨软骨支架 力学性能 流体性能
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Revision of Water Function Division and Countermeasures for Water Resources Protection in Jiangjin District of Chongqing City in China
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作者 侯新 《Journal of Landscape Research》 2011年第12期54-57,70,共5页
According to the current situation and development planning of water resources in Jiangjin District of Three Gorge Reservoir Area at the upper reaches of Yangtze River,by combining with social needs,through the survey... According to the current situation and development planning of water resources in Jiangjin District of Three Gorge Reservoir Area at the upper reaches of Yangtze River,by combining with social needs,through the survey on pollution source and analysis of water quality,based on the Report of Water Function Division of Jiangjin District(2005) ,the adjustment and revision have been conducted on water function divisions,and corresponding protection targets and countermeasures for water resources have been proposed,so that the water function division can comply with the development situation of Jiangjin District,providing a reliable reference for the protection and reasonable utilization of water resources,enhancing the unified and effective supervision of water resources,promoting the sustainable use of water resources in Jiangjin District,and ensuring the sustainable development of regional society and environment. 展开更多
关键词 three Gorges Reservoir Area Jiangjin DISTRICT WATER function DIVISION WATER resources protection COUNTERMEASURES
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Green Functions with Pulsating Sources in A Two-Layer Fluid of Finite Depth 被引量:2
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作者 MANYANGA D.O 段文洋 《China Ocean Engineering》 SCIE EI 2011年第4期609-624,共16页
The derivation of Green function in a two-layer fluid model has been treated in different ways. In a two-layer fluid with the upper layer having a free surface, there exist two modes of waves propagating due to the fr... The derivation of Green function in a two-layer fluid model has been treated in different ways. In a two-layer fluid with the upper layer having a free surface, there exist two modes of waves propagating due to the free surface and the interface. This paper is concerned with the derivation of Green functions in the three dimensional case of a stationary source oscillating. The source point is located either in the upper or lower part of a two-layer fluid of finite depth. The derivation is carried out by the method of singularities. This method has an advantage in that it involves representing the potential as a sum of singularities or multipoles placed within any structures being present. Furthermore, experience shows that the systems of equations resulted from using a singularity method possess excellent convergence characteristics and only a few equations are needed to obtain accurate numerical results. Validation is done by showing that the derived two-layer Green function can be reduced to that of a single layer of finite depth or that the upper Green function coincides with that of the lower, for each case. The effect of the density on the internal waves is demonstrated. Also, it is shown how the surface and internal wave amplitudes are compared for both the wave modes. The fluid in this case is considered to be inviscid and incompressible and the flow is irrotational. 展开更多
关键词 Green function two-layer fluid three dimensions singularities method
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THE APPLICATION OF SPLINE FUNCTION IN THE GEOMETRIC REPRODUCTION OF LOG SHAPE
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作者 于龙梅 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第3期75-78,共4页
The paper introduces a method to get three-dimensional reproduction of log shape by adopting Spline Function in fitting the curve of the finite log data. The method has ad-vantages of higher accuracy, less acquired da... The paper introduces a method to get three-dimensional reproduction of log shape by adopting Spline Function in fitting the curve of the finite log data. The method has ad-vantages of higher accuracy, less acquired data, easier to use, etc. Making use of high-precision drawing function of computer, the graphs of log geometric shape in different visual angles can be achieved easily with this method. It also provided a firm foundation for the determination of optimum saw cutting scheme. 展开更多
关键词 Computer Spline function three-dimensional reproduction Log shape Optimum saw cutting
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“城乡两栖”视角下农村宅基地“三权分置”问题研究 被引量:2
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作者 郑雄飞 刘婕 《华东师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第2期110-119,180,181,共12页
“三权分置”改革有助于化解“城乡两栖”背景下宅基地的制度困境。在我国城镇化进程和乡村振兴过程中,城乡人口双向流动以及异地居住的“城乡两栖”现象日益明显。人口迁居带来了宅基地及其地上房屋所承载的居住功能弱化,而它们的财产... “三权分置”改革有助于化解“城乡两栖”背景下宅基地的制度困境。在我国城镇化进程和乡村振兴过程中,城乡人口双向流动以及异地居住的“城乡两栖”现象日益明显。人口迁居带来了宅基地及其地上房屋所承载的居住功能弱化,而它们的财产功能和社会情感功能则逐渐增强。总体来看,现有部分制度抑制了宅基地的产权权能开发和资产价值挖掘,造成了闲置、低效利用与隐性流转共存的困局,需要合理推进“三权分置”改革。宅基地“三权分置”改革受到乡村治理机制不完善、产权边界不清晰、农民宅基地权属观念模糊等因素掣肘,面临所有权主体虚置、过度“资本化”等诸多问题,阻碍了相关体制机制创新。为此,“三权分置”改革需要清晰界定“三权”边界,明确宅基地的法权属性,在保障农户资格权的基础上适度拓展宅基地使用权,推动实现宅基地的财产价值;引入市场机制多元盘活闲置宅基地,进而提高土地资源利用效率。 展开更多
关键词 宅基地 “三权分置” 功能演变 “城乡两栖”
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THREE-DIMENSIONAL ANALYSIS OF THE FLOW IN THE CYCLONES
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作者 奚致中 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第6期557-564,共8页
This paper gives the detailed mathematical expression of the flow in the spherical coordinates system. Applying the law of conservation of mass, movement theorem of steady flow, and applying the mathematical method of... This paper gives the detailed mathematical expression of the flow in the spherical coordinates system. Applying the law of conservation of mass, movement theorem of steady flow, and applying the mathematical method of stream function with consideration of the axis symmetry, the three components of velocity quantum of the flow are deduced in detail. Here the overall analysis of the flow is presented in the view of the concept of whole, and the paper gives the necessary corrections of some results of Ref.[1] 展开更多
关键词 three-dimensional flow stream function steady flow incompressible fluid
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Quantum Distribution Functions for Dusty Plasma in Saturn’s Rings by Using Curvilinear Coordinates
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作者 Nagat Abd El Rahman Hussein Abd El-Rahim Hassan Ahmed Esraa Gamal Sayed 《International Journal of Astronomy and Astrophysics》 2019年第2期115-132,共18页
This study aims to estimate the quantum Bogoliubov-Born-Green-Kirkwood-Yvon (BBGKY) hierarchy in curvilinear coordinates. We used the results to calculate the quantum binary and triplet distribution functions in curvi... This study aims to estimate the quantum Bogoliubov-Born-Green-Kirkwood-Yvon (BBGKY) hierarchy in curvilinear coordinates. We used the results to calculate the quantum binary and triplet distribution functions in curvilinear coordinates. The analytical form of the quantum distribution functions was obtained for dusty plasma in Saturn’s rings model. We use particles-in-cell (PIC) simulations to find a visualization of dusty three-component plasma phase space in curvilinear coordinates. Our results were compared with others. 展开更多
关键词 DUSTY PLASMA BINARY and TRIPLET Distribution functions three Component PLASMA BBGKY HIERARCHY
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Analysis of dynamic stress intensity factors of three-point bend specimen containing crack
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作者 陈爱军 曹俊俊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第2期203-210,共8页
A new formula is obtained to calculate dynamic stress intensity factors of the three-point bending specimen containing a single edge crack in this study. Firstly, the weight function for three-point bending specimen c... A new formula is obtained to calculate dynamic stress intensity factors of the three-point bending specimen containing a single edge crack in this study. Firstly, the weight function for three-point bending specimen containing a single edge crack is derived from a general weight function form and two reference stress intensity factors, the coefficients of the weight function are given. Secondly, the history and distribution of dynamic stresses in uncracked three-point bending specimen are derived based on the vibration theory. Finally~ the dynamic stress intensity factors equations for three-pointing specimen with a single edge crack subjected to impact loadings are obtained by the weight function method. The obtained formula is verified by the comparison with the numerical results of the finite element method (FEM). Good agreements have been achieved. The law of dynamic stress intensity factors of the three-point bending specimen under impact loadings varing with crack depths and loading rates is studied. 展开更多
关键词 CRACK dynamic stress intensity factor weight function method three-pointbending specimen loading rate
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