Recently, Tsai et al., Liao et al. and Li et al. each proposed a multi-server authentication protocol. They claimed their protocols are secure and can withstand various attacks. However, we found some security loopholes in each of their schemes, for example, both Tsai et al.’s and Liao et al.‘s schemes suffers from server spoofing attack by an insider server. Li et al.s’ suffers from the lost s...

We have used liquid exfoliation of hexagonal Boron-Nitride (BN) to prepare composites of BN nanosheets of three different sizes in polyvinylchloride matrices. These composites show low levels of reinforcement, consistent with poor alignment of the nanosheets as-described by a modified version of Halpin-Tsai theory. However, drawing of the composites to 300% strain results in a considerable incr...

The work focuses on the post- buckling behavior of functionally graded graphene platelet (FG-GPL)-reinforced porous thick rings with open-cell internal cavities under a uniform external pressure. generalized rule mixture and modified Halpin–Tsai model are here used to evaluate effective mechanical properties ring. Three types porosity patterns assumed together five different GPL distributions a...

The effect of grain angle (GA) on shear strength of Douglasfi r has been evaluated. Shear block specimens with a GA varying from 0 to 90 ° was loaded in the shear plane, resulting in failure mode transitioning from parallel to grain shear to rolling shear. As expected, shear strength decreased as the GA increased from 0 ° to 90 ° . A root-mean-square equation was found to be suitable to predict...

Tsai and Chan (2003) has recently introduced the Continuous-time AutoRegressive Fractionally Integrated Moving-Average (CARFIMA) models useful for studying long-memory data. We consider the estimation of the CARFIMA models with discrete-time data by maximizing the Whittle likelihood. We show that the quasimaximum likelihood estimator is asymptotically normal and efficient. Finite-sample propert...

Two nuclear signalling pathways for vitamin D. Nature 1993;361: 657-60. (47) Elstner E, Linker-Israeli M, Umiel T, Le J, Grillier I, Said J, et al. Combination of a potent 20-epi-vitamin D3 analogue (KH 1060) with 9-cisretinoic acid irreversibly inhibits clonal growth, decreases bcl-2 expression, and induces apoptosis in HL-60 leukemic cells. Cancer Res 1996;56: 3570-6. (48) Elstner E, Linker-I...

This study aims to investigate whether different player-matching mechanisms in educational multi-player online games (MOGs) can affect students’ learning performance, enjoyment perception and gaming behaviors. Based on the multi-player quiz game, TRIS-Q, developed by Tsai, Tsai and Lin (2015) using a free player-matching (FPM) mechanism, the same game, but incorporating an automatic player-matc...

, A numerical solution to the integro-differential equation describing the energy'distribution of a beam of electrons which has passed through matter, losing energy by radiation only, has been obtained utilizing a finite difference mesh method. Solutions were obtained for thicknesses of up to 0.1 radiation lengths for a complete screening approximation to the energy loss equation. The accuracy ...

Abstract This article re-examines the nonlinear vibration and bending responses of porous sandwich cylindrical panels reinforced by graphene platelets resting on elastic foundations in thermal environments. The platelet-reinforced composite (GPLRC) core is assumed to be multilayers, each layer may have different porosity coefficient values achieve a piece-wise functionally graded pattern. By in...