Spatial straight line mechanisms are a class of spatial mechanisms whose end-effectors generate the trajectory with the form of exact straight lines, which have potential applications in many industrial sectors. This ...Spatial straight line mechanisms are a class of spatial mechanisms whose end-effectors generate the trajectory with the form of exact straight lines, which have potential applications in many industrial sectors. This study aims to synthesis the spatial straight line mechanisms with only revolute joints, meaning that no prismatic joints are included. According to the generalized function sets and the law of one dimensional rotation, the type of compositions of characteristic and the corresponding conditions are derived. Furthermore, some novel symmetrical and asymmetrical spatial straight line mechanisms are synthesized through assembling specific kinematic chains under the corresponding conditions. Finally, several synthesized spatial straight line mechanisms are illustrated to show the effectiveness of the synthesis methodology.展开更多
Various kinds of Riemann boundary value problems (BVPs) for analytic functions on closed curves or on open arc, doubly periodic Riemann BVPs, doubly quasi-periodic Riemann BVPs, and BVPs for polyanalytic functions hav...Various kinds of Riemann boundary value problems (BVPs) for analytic functions on closed curves or on open arc, doubly periodic Riemann BVPs, doubly quasi-periodic Riemann BVPs, and BVPs for polyanalytic functions have been widely investigated in [1-8]. The main ap- proach is to use the decomposition of polyanalytic functions and their generalization to transform the boundary value problems to their corresponding boundary value problems for analytic functions. Recently, inverse Riemann BVPs for generalized analytic functions or bianalytic functions have been investigated in [9-12]. In this paper, we consider a kind of Riemann BVP of non-normal type on the infinite straight line and discuss the solvable conditions and the general solution for it.展开更多
根据2 k W直筒型集鱼灯的实测配光分布,以大型光诱鱿钓渔船"新世纪52号"为例,对该船的水中照度分布进行了计算。结果表明:渔船集鱼灯总功率为360 k W时,10.000 lx的等照度曲线水平方向最远约为80 m,水深方向为32 m;0.100 lx...根据2 k W直筒型集鱼灯的实测配光分布,以大型光诱鱿钓渔船"新世纪52号"为例,对该船的水中照度分布进行了计算。结果表明:渔船集鱼灯总功率为360 k W时,10.000 lx的等照度曲线水平方向最远约为80 m,水深方向为32 m;0.100 lx照度最深可约至50 m,最远约为260 m;当总功率减为180 k W时,等照度曲线所在水层仅减少约5 m。以0.010 lx为诱集鱿鱼的最低照度,集鱼灯功率从180 k W增加到360 k W,有效诱集距离从620 m增加到750 m,约能增加21.1%;如能将该船的灯高增大0.5 m,则可增加12.0%的有效水体体积;如能将灯距增大0.05 m,则可增加4.4%的有效水体体积。展开更多
基金National Basic Research Program of China (973 Program,No.2006CB705402)National Science and Technology Major Project,China(No.2009ZX04013-021)National Natural Science Foundation of China (No.51008288)
文摘Spatial straight line mechanisms are a class of spatial mechanisms whose end-effectors generate the trajectory with the form of exact straight lines, which have potential applications in many industrial sectors. This study aims to synthesis the spatial straight line mechanisms with only revolute joints, meaning that no prismatic joints are included. According to the generalized function sets and the law of one dimensional rotation, the type of compositions of characteristic and the corresponding conditions are derived. Furthermore, some novel symmetrical and asymmetrical spatial straight line mechanisms are synthesized through assembling specific kinematic chains under the corresponding conditions. Finally, several synthesized spatial straight line mechanisms are illustrated to show the effectiveness of the synthesis methodology.
文摘Various kinds of Riemann boundary value problems (BVPs) for analytic functions on closed curves or on open arc, doubly periodic Riemann BVPs, doubly quasi-periodic Riemann BVPs, and BVPs for polyanalytic functions have been widely investigated in [1-8]. The main ap- proach is to use the decomposition of polyanalytic functions and their generalization to transform the boundary value problems to their corresponding boundary value problems for analytic functions. Recently, inverse Riemann BVPs for generalized analytic functions or bianalytic functions have been investigated in [9-12]. In this paper, we consider a kind of Riemann BVP of non-normal type on the infinite straight line and discuss the solvable conditions and the general solution for it.
文摘根据2 k W直筒型集鱼灯的实测配光分布,以大型光诱鱿钓渔船"新世纪52号"为例,对该船的水中照度分布进行了计算。结果表明:渔船集鱼灯总功率为360 k W时,10.000 lx的等照度曲线水平方向最远约为80 m,水深方向为32 m;0.100 lx照度最深可约至50 m,最远约为260 m;当总功率减为180 k W时,等照度曲线所在水层仅减少约5 m。以0.010 lx为诱集鱿鱼的最低照度,集鱼灯功率从180 k W增加到360 k W,有效诱集距离从620 m增加到750 m,约能增加21.1%;如能将该船的灯高增大0.5 m,则可增加12.0%的有效水体体积;如能将灯距增大0.05 m,则可增加4.4%的有效水体体积。
