We show that the unit tangent bundle of S4 and a real cohomology CP 3 admit Riemannian metrics with positive sectional curvature almost everywhere. These are the only examples so far with positive curvature almost everywhere that are not also known to admit positive curvature. AMS Classi cation numbers Primary: 53C20 Secondary: 53C20, 58B20, 58G30

This paper presents a novel module-based software framework for multimedia E-learning. Interface of each module is standardized based on IEEE P1484 LTSA so that it easily communicates and combines with other modules. It can be easily reconfigured to various education models with flexibility and adaptability, since it only needs to change connection status between modules. A user can search othe...

In this paper, the Fourier series expansion of Tangent polynomials higher order is derived using Cauchy residue theorem. Moreover, some variations higher-order are defined by mixing concept with that Bernoulli and Genocchi polynomials, Tangent–Bernoulli Tangent–Genocchi polynomials. Furthermore, expansions these also

In this paper we develop a process modeling framework for the evaluation and formal validation of Panama Canal system operations. Componentand architecture-level processes are organized into a three level hierarchy and modeled in LTSA. Safety and progress requirements are formally expressed as processes that can be evaluated through compositional and search processes, respectively.

A branched structure is observable in draining and irrigation systems, in electric power supply systems and in natural objects like the blood vessels, the river basins or the trees. Recent approaches of these networks derive their branched structure from an energy functional whose essential feature is to favor wide routes. Given a flow s in a river, a road, a tube or a wire, the transportation ...

Compared to the error factors of the Linear Array Digital Sun Sensor (DSS), those of the Area Array DSS are complicated and methods used for error compensation are not valid or simple enough. This paper presents the main error factors of the Area Array DSS and proposes an effective method to compensate them. The procedure of error compensation of Area Array DSS includes three steps. First, the ...

Nonlinear resistive field grading materials are widely used in the electrical and electronic applications, usually researched based on initial nonlinear conductivity characteristics of synthetic materials. However, long-term stability these rarely reported. In this paper, effects thermal ageing material electric distribution DC cone spacers studied. The 30 wt.% SiC/epoxy micro-composites prepar...