The quarter-circular caisson breakwater （QCB） is a new type of breakwater, and it can be applied in deepwater. The stability of QCB under wave force action can be enhanced, and the rubble mound engineering can be le...The quarter-circular caisson breakwater （QCB） is a new type of breakwater, and it can be applied in deepwater. The stability of QCB under wave force action can be enhanced, and the rubble mound engineering can be less than that of semi-circular breakwaters in deepwater. In order to study the wave force distribution acting on the QCB, to find wave force formula for this type of breakwater, firstly in this paper, the distribution characteristics of the horizontal force, the downward vertical force and the uplift force on the breakwater were gotten based on physical model wave flume experiments and on the analysis of the wave pressure experimental data. Based on a series of physical model tests acted by irregular waves, a kind of calculation method, which was modified by Goda formula, was proposed to carry out the wave force on the QCB. Secondly, the reliability method with correlated variables was adopted to analyze the QCB, considering the high correlation between wave forces or moments. Utilizing the observed wave data in engineering field, the reliability index and failure probability of QCB were obtained. Finally, a factor Q=0.9 is given to modify the zero pressure height above SWL of QCB, and wave force partial coefficient 1.34 to the design expressions of QCB for anti-sliding, as well as 1.67 for anti-overturning, were presented.展开更多
By constructing the index system of " four forces" and adopting the fuzzy comprehensive evaluation model under the new membership function,this paper makes an empirical analysis on the safety of agricultural...By constructing the index system of " four forces" and adopting the fuzzy comprehensive evaluation model under the new membership function,this paper makes an empirical analysis on the safety of agricultural industry in Hunan Province from 2001 to 2013. The results show that the safety degree of Hunan agricultural industry is always in the range of " basically safe" and above,it was in the range of " safe" in 2010 and 2011,in the range of " very safe" in 2013,and in the range of " basically safe" in the other years; the indices of productive force,competitiveness and dependency of agricultural industry is always in the state of " basically safe" or above,while the index of control force of agricultural industry is in the trend of changing from " basically safe" to " unsafe". Therefore,it is necessary to accelerate the innovation process of agricultural industry and improve the export quality of agricultural products,especially to establish a stricter market mechanism for foreign capital entry and foreign capital merger and acquisition,improve the control power of agricultural industry,and provide favorable guarantee for the safety of agricultural industry.展开更多
Capillary interactions are fundamentally important in many scientific and industrial fields. However, most existing models of the capillary bridges and capillary forces between two solids with a mediated liquid, are b...Capillary interactions are fundamentally important in many scientific and industrial fields. However, most existing models of the capillary bridges and capillary forces between two solids with a mediated liquid, are based on extremely simple geometrical configurations, such as sphere-plate, sphere-sphere, and plate-plate. The capillary bridge and capillary force between two axisymmetric power-law profile particles with a mediated constant-volume liquid are investigated in this study. A dimensionless method is adopted to calculate the capillary bridge shape between two power-law profile particles based on the Young-Laplace equation. The critical rupture criterion of the liquid bridge is shown in four forms that produce consistent results. It was found that the dimensionless rupture distance changes little when the shape index is larger than 2. The results show that the power-law index has a significant influence on the capillary force between two power-law particles. This is directly attributed to the different shape profiles of power-law particles with different indices. Effects of various other parameters such as ratio of the particle equivalent radii, liquid contact angle, liquid volume, and interparticle distance on the capillary force between two power-law particles are also examined.展开更多
基金Supported by the Natural Science Foundation of Hebei Province （Grant No. E2012201057） the Scientific and Technological Projects of Hebei Province （Grant No. 2009056） the Natural Science Foundation of Tianjin （Grant No. 10JCYBJC03700）
文摘The quarter-circular caisson breakwater （QCB） is a new type of breakwater, and it can be applied in deepwater. The stability of QCB under wave force action can be enhanced, and the rubble mound engineering can be less than that of semi-circular breakwaters in deepwater. In order to study the wave force distribution acting on the QCB, to find wave force formula for this type of breakwater, firstly in this paper, the distribution characteristics of the horizontal force, the downward vertical force and the uplift force on the breakwater were gotten based on physical model wave flume experiments and on the analysis of the wave pressure experimental data. Based on a series of physical model tests acted by irregular waves, a kind of calculation method, which was modified by Goda formula, was proposed to carry out the wave force on the QCB. Secondly, the reliability method with correlated variables was adopted to analyze the QCB, considering the high correlation between wave forces or moments. Utilizing the observed wave data in engineering field, the reliability index and failure probability of QCB were obtained. Finally, a factor Q=0.9 is given to modify the zero pressure height above SWL of QCB, and wave force partial coefficient 1.34 to the design expressions of QCB for anti-sliding, as well as 1.67 for anti-overturning, were presented.
基金Supported by Key Research and Development Plan of Hunan Science and Technology Program in 2015(2015ZK3030)
文摘By constructing the index system of " four forces" and adopting the fuzzy comprehensive evaluation model under the new membership function,this paper makes an empirical analysis on the safety of agricultural industry in Hunan Province from 2001 to 2013. The results show that the safety degree of Hunan agricultural industry is always in the range of " basically safe" and above,it was in the range of " safe" in 2010 and 2011,in the range of " very safe" in 2013,and in the range of " basically safe" in the other years; the indices of productive force,competitiveness and dependency of agricultural industry is always in the state of " basically safe" or above,while the index of control force of agricultural industry is in the trend of changing from " basically safe" to " unsafe". Therefore,it is necessary to accelerate the innovation process of agricultural industry and improve the export quality of agricultural products,especially to establish a stricter market mechanism for foreign capital entry and foreign capital merger and acquisition,improve the control power of agricultural industry,and provide favorable guarantee for the safety of agricultural industry.
文摘Capillary interactions are fundamentally important in many scientific and industrial fields. However, most existing models of the capillary bridges and capillary forces between two solids with a mediated liquid, are based on extremely simple geometrical configurations, such as sphere-plate, sphere-sphere, and plate-plate. The capillary bridge and capillary force between two axisymmetric power-law profile particles with a mediated constant-volume liquid are investigated in this study. A dimensionless method is adopted to calculate the capillary bridge shape between two power-law profile particles based on the Young-Laplace equation. The critical rupture criterion of the liquid bridge is shown in four forms that produce consistent results. It was found that the dimensionless rupture distance changes little when the shape index is larger than 2. The results show that the power-law index has a significant influence on the capillary force between two power-law particles. This is directly attributed to the different shape profiles of power-law particles with different indices. Effects of various other parameters such as ratio of the particle equivalent radii, liquid contact angle, liquid volume, and interparticle distance on the capillary force between two power-law particles are also examined.
