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声誉积累优势还是绩效积累优势?政府R&D补贴分配中“粘性”效应探究 被引量:10
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作者 朱桂龙 蔡朝林 陈朝月 《科学学与科学技术管理》 CSSCI CSCD 北大核心 2019年第3期43-55,共13页
通过探究政府R&D补贴分配的持续性问题,有利于减少政府行为失范,提高政府R&D补贴效率。分别从声誉积累优势和绩效积累优势探究影响政府R&D补贴分配中“粘性”效应的因素,采用2010-2013年广东省498家制造业民营企业的面板数... 通过探究政府R&D补贴分配的持续性问题,有利于减少政府行为失范,提高政府R&D补贴效率。分别从声誉积累优势和绩效积累优势探究影响政府R&D补贴分配中“粘性”效应的因素,采用2010-2013年广东省498家制造业民营企业的面板数据,应用转移概率矩阵、Probit回归分析以及PSM方法进行实证检验,结果发现:基于广东的实证数据表明,广东省政府R&D补贴“粘性”效应更有可能是基于绩效积累优势的挑选机制,进一步基于企业创新链视角检验政府R&D补贴“粘性”效应对企业创新的影响发现:政府R&D补贴“粘性”效应有利于企业研发强度提升,对企业不同模式的技术获取战略均存在积极显著的影响,但对企业新产品产值的影响不显著。 展开更多
关键词 “粘性”效应 声誉积累 绩效积累 创新过程
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Coupled effect of viscosity enhancing admixtures and superplasticizers on rheological behavior of cement paste 被引量:5
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作者 元强 刘文涛 +3 位作者 王超 邓德华 刘赞群 龙广成 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第9期2172-2179,共8页
The coupled effect of viscosity enhancing admixtures(VEA)and superplasticizer(SP)on the rheological behavior of cement paste was investigated in this work.Two types of VEAs,including hydroxypropyl methylcellulose(HPMC... The coupled effect of viscosity enhancing admixtures(VEA)and superplasticizer(SP)on the rheological behavior of cement paste was investigated in this work.Two types of VEAs,including hydroxypropyl methylcellulose(HPMC)and Welan gum,and two types of SPs,i.e.polycarboxylate(PCA)and polynaphthalenesulfonate(PNS)were used as admixtures for cement paste.Rheological curves of cement paste and simulated pore solution containing VEA and SP were tested.Simulated pore solution test results show that molecules of different SPs may generate different effects on the viscosity of VEA solutions.Hershel-Bulkley(H-B)model was used to fit rheological curve of cement paste.Strong interaction between PNS and HPMC was observed in this work. 展开更多
关键词 rheology cement viscosity enhancing admixture SUPERPLASTICIZER
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Finite element formulation of active constraining layer damping plate using laminate theory
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作者 邓年春 邹振祝 黄文虎 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第4期351-355,共5页
A new finite element modeling method has been developed using laminate theory in a virtual work principle for active constraining layer damping plate. The frequency dependent modulus of viscoelastic material is descri... A new finite element modeling method has been developed using laminate theory in a virtual work principle for active constraining layer damping plate. The frequency dependent modulus of viscoelastic material is described by introducing a few dissipation coordinates, known as GHM (Golla-Hughes-McTavish) method, a standard linear system with constant coefficient. The effectiveness of this method is validated by experimental model. Compared with conventional methods, this method can reduce a number of degrees of freedom and improve accuracy, provides a good model for analogous configurations. 展开更多
关键词 active constraining layer damping VISCOELASTIC piezoelectric effect
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Bonding Characteristics and Flexural Stiffening Effect of Carbon Fibre Reinforced Plastics Strand Sheets Bonded to Steel Beams 被引量:1
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作者 Masatsugu Nagai Yuya Hidekuma +3 位作者 Takeshi Miyashita Yusuke Okuyama Akiya Kudo Akira Kobayashi 《Journal of Civil Engineering and Architecture》 2015年第2期207-212,共6页
Corrosion of steel structures is unavoidable and the structural performance decreases dramatically due to the corrosion. As a repairing method for corroded steel members, bonding carbon fiber sheets with resin had bee... Corrosion of steel structures is unavoidable and the structural performance decreases dramatically due to the corrosion. As a repairing method for corroded steel members, bonding carbon fiber sheets with resin had been developed. The purpose of this study is to propose the flexural strengthening method for steel members by using CFRP (carbon fiber reinforced polymer) strand sheets. In order to clarify the stiffening effect and the debonding characteristics of CFRP strand sheets, and to optimize the strengthening design specifications, the flexural tests using high tension steel beams strengthened with CFRP strand sheets are performed. Two cases of experiments are carried out. In Experiment 1, the result from previous research is reflected in the strengthening design. Moreover in Experiment 2, the debonding characteristics obtained from Experiment 1 are reflected. As a result, it was clarified that CFRP strand sheets have stiffening effect equivalent to the theoretical value and its debonding property is practically high enough when FRP (fiber reinforcement polymer) sheets have an appropriate bonding length. 展开更多
关键词 CFRP strand sheets corrosion DEBONDING flexural strengthening steel members.
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Thermal Effects on Bond Properties of GFRP Rebars Embedded in Concrete
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作者 Radhouane Masmoudi Abdelmonem Masmoudi +1 位作者 Atef Daoud Mongi Ben Ouezdou 《Journal of Civil Engineering and Architecture》 2010年第3期1-5,共5页
This paper presents the results of an experimental study on the thermal effects on glass fibre reinforced polymer (GFRP) bars embedded in concrete. The pullout test specimens were subjected to temperatures of 40℃,... This paper presents the results of an experimental study on the thermal effects on glass fibre reinforced polymer (GFRP) bars embedded in concrete. The pullout test specimens were subjected to temperatures of 40℃, 60℃ and 80℃ during a continuous four months-period of time. The results were compared to the reference specimens (room temperature). It was found that up to 60℃, the loss in bond strength due to the temperature is not significant, whereas for the 80℃-temperature a reduction of 14% in the bond strength is observed. Also, the bond-slip relationship was modelled using the CMR-model and new coefficients are proposed for the bond-slip behaviour of GFRP bars. 展开更多
关键词 Ageing bond behaviour CONCRETE glass fibre reinforced polymer (GFRP) pullout tests.
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Analysis on effective stress formula and consolidation of gassy muddy clay
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作者 徐浩峰 应宏伟 +1 位作者 谢新宇 谢康和 《Journal of Central South University》 SCIE EI CAS 2014年第4期1594-1599,共6页
In order to found an applicable equation of consolidation for gassy muddy clay, an effective stress formula of gas-charged nearly-saturated soils was introduced. And then, a consolidation equation was derived. Subsequ... In order to found an applicable equation of consolidation for gassy muddy clay, an effective stress formula of gas-charged nearly-saturated soils was introduced. And then, a consolidation equation was derived. Subsequently, supposing soils were under tangential loading, the expressions of pore water pressure were presented. The analytic solution of pore water pressure was attempted to be validated by the measured values in a real embankment. The parameters in the expressions of pore water pressure were gotten by the method of trial. The result shows that the consolidation model is rational and the analytic solution of pore water pressure is correct. The following conclusions can be made: 1) the influence of bubbles on the compressibility of pore fluid should be considered; 2) the effective stress would be influenced by bubbles, and the consolidation would depend on the compressibility of soil skeleton: the softer the soils are, the more distinct the influence of bubbles is; for normal clay, the influence of bubbles on the effective stress may be commonly neglected. 展开更多
关键词 muddy clay gas bubble consolidation effective stress unsaturated soil
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Hyperbolic structure and stickiness effect: A case of a 2D area-preserving twist mapping
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作者 ZHOU LiYong LI Jian +1 位作者 CHENG Jian SUN YiSui 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第9期1737-1750,共14页
The stickiness effect suffered by chaotic orbits diffusing in the phase space of a dynamical system is studied in this paper.Previous works have shown that the hyperbolic structures in the phase space play an essentia... The stickiness effect suffered by chaotic orbits diffusing in the phase space of a dynamical system is studied in this paper.Previous works have shown that the hyperbolic structures in the phase space play an essential role in causing the stickiness effect.We present in this paper the relationship between the stickiness effect and the geometric property of hyperbolic structures.Using a two-dimensional area-preserving twist mapping as the model,we develop the numerical algorithms for computing the positions of the hyperbolic periodic orbits and for calculating the angle between the stable and unstable manifolds of the hyperbolic periodic orbit.We show how the stickiness effect and the orbital diffusion speed are related to the angle. 展开更多
关键词 stickiness effect hyperbolic structure stable and unstable manifolds
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Experimental Study of the Viscous Pump with a Helical Channel Rotor:Torsion Effect of the Channel
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作者 Yasutaka HAYAMIZU Kyoji YAMAMOTO +3 位作者 Shinichiro YANASE Toru HYAKUTAKE Shinichi MORITA Shigeru OHTSUKA 《Journal of Thermal Science》 SCIE EI CAS CSCD 2010年第2期154-159,共6页
The viscous pump,which has a rotor with a helical square channel,is studied experimentally.The non-dimen-sional channel curvature is taken to be about 0.1.Three types of torsion of the channel are made to investigate ... The viscous pump,which has a rotor with a helical square channel,is studied experimentally.The non-dimen-sional channel curvature is taken to be about 0.1.Three types of torsion of the channel are made to investigate the torsion effect on the flow characteristics.We measure the flux through the channel at a constant rotor speed by changing the pressures at the entrance and exit of the pump.We also observe the secondary flow at a cross-section of the channel.Some of the results obtained are shown as follows:The friction factor along the channel to get the same flux is large for large channel torsion at a constant rotation,and becomes small when the favorable rotation of the rotor to the flow is applied.As for the secondary flow in a cross-section,there appear several types of vortex.When there is no rotation,the secondary flow is almost a symmetric two-vortex type for small flux as is the ordinary Dean vortex,but it changes to a four-vortex type when the flux is large.The secondary flow becomes asymmetric as the rotation is applied.We have unsteady flow patterns at large flux and rotation. 展开更多
关键词 Viscous Pump Helical Channel Torsion Effect Secondary Flow Flow Visualization Dean Number Taylor Number
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Heat transfer analysis of bi-viscous ciliary motion fluid 被引量:1
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作者 Noreen Sher Akbar Z. H. Khan 《International Journal of Biomathematics》 2015年第2期219-231,共13页
The impulsion system of cilia motion is deliberated by biviscosity fluid model. The problem of two-dimensional motion of biviscosity fluid privileged in a symmetric channel with ciliated walls is considered. The feat... The impulsion system of cilia motion is deliberated by biviscosity fluid model. The problem of two-dimensional motion of biviscosity fluid privileged in a symmetric channel with ciliated walls is considered. The features of ciliary structures are resolute by the supremacy of viscous effects above inertial possessions by the long-wavelength and low Reynolds approximation. Closed-form solutions for the longitudinal pressure gradient, temperature and velocities are obtained. The pressure gradient and volume flow rate for different values of the biviscosity are also premeditated. The flow possessions for the biviscosity fluid resolute as a function of the cilia and metachronal wave velocity. 展开更多
关键词 Ciliary motion symmetric channel biviscosity fluid heat transfer exact solutions.
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MHD peristaltic flow in an inclined channel with heat and mass transfer
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作者 Maryiam Javed T. Hayat A. Alsaedi 《International Journal of Biomathematics》 2016年第1期191-205,共15页
This paper addresses the peristaltic flow of magnetohydrodynamic viscous fluid in an inclined compliant wall channel. Different wave amplitudes and phases ensure asymme- try in the channel flow configuration. Simultan... This paper addresses the peristaltic flow of magnetohydrodynamic viscous fluid in an inclined compliant wall channel. Different wave amplitudes and phases ensure asymme- try in the channel flow configuration. Simultaneous effects of heat and mass transfer are also considered. Viscous dissipation effect is present. The flow and heat transfer are investigated under long wavelength and low Reynolds number assumption. The expres- sions for stream function, axial velocity, temperature and concentration are obtained. The solution expressions for physical quantities are sketched and discussed. It is found that Brinkman and Hartman numbers have reverse effect on the temperature. 展开更多
关键词 Inclined channel compliant wall viscous dissipation MHD.
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Advanced Study of Unsteady Heat and Chemical Reaction with Ramped Wall and Slip Effect on a Viscous Fluid
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作者 Ayesha Sohail K.Maqbool +1 位作者 Noreen Sher Akbar Muhammad Younas 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第3期301-308,共8页
This paper investigate the effect of slip boundary condition, thermal radiation, heat source, Dufour number,chemical reaction and viscous dissipation on heat and mass transfer of unsteady free convective MHD flow of a... This paper investigate the effect of slip boundary condition, thermal radiation, heat source, Dufour number,chemical reaction and viscous dissipation on heat and mass transfer of unsteady free convective MHD flow of a viscous fluid past through a vertical plate embedded in a porous media. Numerical results are obtained for solving the nonlinear governing momentum, energy and concentration equations with slip boundary condition, ramped wall temperature and ramped wall concentration on the surface of the vertical plate. The influence of emerging parameters on velocity,temperature and concentration fields are shown graphically. 展开更多
关键词 free convection thermal radiation MHD viscous dissipation chemical reaction heat source Dufour number porous media
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