This paper studies the wall-bounded flow around a cylindrical at a high Reynolds numbers body in a determined computational domain, with simulations of the 3-D, turbulent concentric annulus flow in a straight pipe. Nu...This paper studies the wall-bounded flow around a cylindrical at a high Reynolds numbers body in a determined computational domain, with simulations of the 3-D, turbulent concentric annulus flow in a straight pipe. Numerical results show that a reversing zone, appearing as a tongue zone with nested velocities higher than the surrounding area, exists behind the cylindrical body. The annulus space is a region of high velocity and low pressure. The zero velocity, of combined the X- velocity and the Y- velocity, exists in the cross sections and no vortex shedding is formed behind the attaching cylinders. Among all investigated effecting factors, the diameters of the attaching and the main cylinders affect the wake feature behind the cylindrical body while the main cylinder length does not affect the distribution tendency of the flow field. The diameters of the main cylinder and the pipe affect the pressure values and the distribution tendencies on the main cylinder surface. Obviously, the increase of the pipe diameter reduces the drag coefficient of the cylindrical body and the increase of the diameter of the main cylinder increases the drag coefficient greatly. The numerical investigation of the concentric annulus flow provides foundations for further improvements of the intricate flow studies.展开更多
Previous studies on the behavioral implications of recommender systems suggest that consumer preferences after consumption are malleable and tend to shift towards the ratings presented by a recommender system because ...Previous studies on the behavioral implications of recommender systems suggest that consumer preferences after consumption are malleable and tend to shift towards the ratings presented by a recommender system because of the anchoring effects.Drawing upon the literature on consumer satisfaction,we show that such a view on the anchoring effects of recommender systems is incomplete.Apart from the assimilation effects that pull the consumers’preferences towards the anchor,the contrast effects may shift their preferences in the other direction.Therefore,we theoretically hypothesize that the impacts of recommendations on consumers’constructed preferences are dependent on the level of deviation of the presented rating.The hypotheses are validated through a laboratory experiment.Our findings extend the existing literature on behavioral implications of recommender systems and provide a more comprehensive theoretical lens for understanding the anchoring effects,which may offer helpful insights for improving the design and use of recommender systems.展开更多
The effect of dielectric constant contrast and the filling factor to the photonic bandgap in a 2-D square lattice photonic crystal is discussed. The location, width and number of photonic bandgap can be modulated.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51179116,51109155)
文摘This paper studies the wall-bounded flow around a cylindrical at a high Reynolds numbers body in a determined computational domain, with simulations of the 3-D, turbulent concentric annulus flow in a straight pipe. Numerical results show that a reversing zone, appearing as a tongue zone with nested velocities higher than the surrounding area, exists behind the cylindrical body. The annulus space is a region of high velocity and low pressure. The zero velocity, of combined the X- velocity and the Y- velocity, exists in the cross sections and no vortex shedding is formed behind the attaching cylinders. Among all investigated effecting factors, the diameters of the attaching and the main cylinders affect the wake feature behind the cylindrical body while the main cylinder length does not affect the distribution tendency of the flow field. The diameters of the main cylinder and the pipe affect the pressure values and the distribution tendencies on the main cylinder surface. Obviously, the increase of the pipe diameter reduces the drag coefficient of the cylindrical body and the increase of the diameter of the main cylinder increases the drag coefficient greatly. The numerical investigation of the concentric annulus flow provides foundations for further improvements of the intricate flow studies.
基金the TsinghuaUniversity Initiative Scientific Research Program under Grant No.2019THZWYX08the MOE Project of Key Research Institute of Humanities and Social Sciences at Universities No.17JJD630006the Research Center for Interactive Technology Industry TsinghuaUniversity under Grant No.RCITI2022T002.
文摘Previous studies on the behavioral implications of recommender systems suggest that consumer preferences after consumption are malleable and tend to shift towards the ratings presented by a recommender system because of the anchoring effects.Drawing upon the literature on consumer satisfaction,we show that such a view on the anchoring effects of recommender systems is incomplete.Apart from the assimilation effects that pull the consumers’preferences towards the anchor,the contrast effects may shift their preferences in the other direction.Therefore,we theoretically hypothesize that the impacts of recommendations on consumers’constructed preferences are dependent on the level of deviation of the presented rating.The hypotheses are validated through a laboratory experiment.Our findings extend the existing literature on behavioral implications of recommender systems and provide a more comprehensive theoretical lens for understanding the anchoring effects,which may offer helpful insights for improving the design and use of recommender systems.
基金This work was supported by the National Nature Science Foundation of China under grants No. 60225011major state basic research program under grant No. G20000366
文摘The effect of dielectric constant contrast and the filling factor to the photonic bandgap in a 2-D square lattice photonic crystal is discussed. The location, width and number of photonic bandgap can be modulated.
