Superposition method for analysis of free-edge stresses

Superposition techniques were used to transform the edge stress problem for composite laminates into a more lucid form. By eliminating loads and stresses not contributing to interlaminar stresses, the essential aspects of the edge stress problem are easily recognized. Transformed problem statements were developed for both mechanical and thermal loads. Also, a technique for approximate analysis using a two dimensional plane strain analysis was developed. Conventional quasi-three dimensional analysis was used to evaluate the accuracy of the transformed problems and the approximate two dimensional analysis. The transformed problems were shown to be exactly equivalent to the original problems. The approximate two dimensional analysis was found to predict the interlaminar normal and shear stresses reasonably well

Heat and Mass Transfer to Unsteady MHD Viscoelastic Slip Flow through a Porous Medium with Chemical Reaction

In the present paper, an analysis is carried out to heat and mass transfer to unsteady flow of an electrically conducting incompressible non-Newtonian viscoelastic fluid filled in a vertical channel in the presence of transverse magnetic field through porous medium with heat source. The fluid and the channel rotate as a solid body with constant angular velocity, about an axis perpendicular to the planes of the plates. The effects of thermal radiation and chemical reaction are taken into account embedded with slip boundary condition. The momentum, energy and concentration equations are solved by using closed-from of analytical solution. The influences of the various parameters entering into the problem are illustrated with the help of graphs. Possible applications of the present study include engineering science and applied mathematics in the context of aerodynamics, geophysics and aeronautics

Water distribution rules and water distribution performance: a case study in the Tambraparani Irrigation System

Irrigation management / Irrigation systems / Performance / Irrigation operation / Irrigation scheduling / Water distribution / Water allocation / Water delivery / Water users' associations / Legislation / Large-scale systems / Bananas / Case studies / India / Tamil Nadu / Tambraparani Irrigation System

Effectiveness of lending for vocational education and training: lessons from World Bank experience

This paper reviews the Bank involvement in the vocational education and training (VET) sub-sector in the 1990s. The paper aims to do just that, by mainly seeking answers to the following questions: 1) How has the Bank performed in its lending services to its clients in VET? 2) How have VET projects performed in terms of meeting stated objectives? 3) What factors led to the success, or failure of Bank operations? Based on what has been learned, the paper provides suggestions about how the performance of future VET interventions can be improved. This review concerns itself primarily with implementation performance, and proposes measures to improve project outcomes.ICT Policy and Strategies,Health Economics&Finance,Health Monitoring&Evaluation,Teaching and Learning,Banks&Banking Reform

Residual thermal and moisture influences on the strain energy release rate analysis of edge delamination

A laminated plate theory analysis is developed to calculate the strain energy release rate associated with edge delamination growth in a composite laminate. The analysis includes the contribution of residual thermal and moisture stresses to the strain energy released. The strain energy release rate, G, increased when residual thermal effects were combined with applied mechanical strains, but then decreased when increasing moisture content was included. A quasi-three-dimensional finite element analysis indicated identical trends and demonstrated these same trends for the individual strain energy release rate components, G sub I and G sub II, associated with interlaminar tension and shear. An experimental study indicated that for T300/5208 graphite-epoxy composites, the inclusion of residual thermal and moisture stresses did not significantly alter the calculation of interlaminar fracture toughness from strain energy release rate analysis of edge delamination data taken at room temperature, ambient conditions

A new look at numerical analyses of free-edge stresses in composite laminates

The edge stress problem for a + or - 45 deg graphite/epoxy laminate was examined. The reliability of the displacement formulated finite element method in analyzing the edge stress problem was investigated. Analyses of two well known elasticity problems, one involving a stress discontinuity and one a singularity, showed that the finite element analysis yields accurate stress distributions everywhere except in two elements closest to the stress discontinuity of singularity. Stress distributions for a + or - 45 deg laminate showed the same behavior near the singularity found in the well known problems with exact solutions. The displacement formulated finite element method appears to be a highly accurate technique for calculating interlaminar stress in composite laminates. The disagreement among the numerical methods was attributed to the unsymmetric stress tensor at the singularity

A Novel IP Traceback Scheme for Spoofing Attack

Internet has been widely applied in various fields, more and more network security issues emerge and catch people\u27s attention. However, adversaries often hide themselves by spoofing their own IP addresses and then launch attacks. For this reason, researchers have proposed a lot of trace back schemes to trace the source of these attacks. Some use only one packet in their packet logging schemes to achieve IP tracking. Others combine packet marking with packet logging and therefore create hybrid IP trace back schemes demanding less storage but requiring a longer search. In this paper, we propose a new hybrid IP trace back scheme with efficient packet logging aiming to have a fixed storage requirement for each router in packet logging without the need to refresh the logged tracking information and to achieve zero false positive and false negative rates in attack-path reconstruction

Power Flow Control/Limiting Short Circuit Current Using TCSC

This paper presents the various advantages of Thyristor Controller Series Capacitor (TCSC), both as a Power Flow Controller, as well as a Short Circuit limiter during faults. The results have been derived and verified from the software PSCAD, and the graphs and calculations are included in the paper. The results and information included in the paper are sufficiently accurate. Keywords: Modelling, power system dynamic stability