Geodesic forms constitute an important family of structural systems. They are efficient and appealing and are employed frequently for dome structures. Data generation for geodesic forms has always been a difficult tas...Geodesic forms constitute an important family of structural systems. They are efficient and appealing and are employed frequently for dome structures. Data generation for geodesic forms has always been a difficult task, from the days of hand data generation using tables of coefficients to today＇s specially written computer programs with many limitations and shortcomings. Formex algebra is a mathematical system which is ideally suited for data generation and configuration processing. The objective of the present paper is to introduce the concepts of formex algebra through which data generation for polyhedric and geodesic forms can be handled with ease and elegance.展开更多
In this paper, a stage-structured predator prey system with birth pulse and disturbed time delay is investigated. The conditions of the prey-extinction periodic solution of the system which are globally attractive hav...In this paper, a stage-structured predator prey system with birth pulse and disturbed time delay is investigated. The conditions of the prey-extinction periodic solution of the system which are globally attractive have been obtained. Furthermore, the sufficient corlditions for the permanence of the system are established. Finally, numerical analysis is given to confirm the theoretical results.展开更多
文摘Geodesic forms constitute an important family of structural systems. They are efficient and appealing and are employed frequently for dome structures. Data generation for geodesic forms has always been a difficult task, from the days of hand data generation using tables of coefficients to today＇s specially written computer programs with many limitations and shortcomings. Formex algebra is a mathematical system which is ideally suited for data generation and configuration processing. The objective of the present paper is to introduce the concepts of formex algebra through which data generation for polyhedric and geodesic forms can be handled with ease and elegance.
文摘In this paper, a stage-structured predator prey system with birth pulse and disturbed time delay is investigated. The conditions of the prey-extinction periodic solution of the system which are globally attractive have been obtained. Furthermore, the sufficient corlditions for the permanence of the system are established. Finally, numerical analysis is given to confirm the theoretical results.
