objective(s):the present study reports the development and validation of a sensitive and rapid extraction method beside high performance liquid chromatographic method for the determination of crocetin in human serum. materials and methods:the hplc method was carried out by using a c18 reversed-phase column and a mobile phase composed of methanol/water/acetic acid (85:14.5:0.5 v/v/v) at the flow...

In this paper a comprehensive approach is presented to improve power swings damping based on direct Lyapunov method. The approach combines superconducting magnetic energy storage (SMES) system with static synchronous compensator (STATCOM). Considering the energy absorption/injection ability of SMES, in transient states the combination exchanges both active and reactive powers with power system....

while the oecd test guidelines and mostly animal assays have been used to study the toxic effects of chemicals for many years, very little is known about the potential toxicity of vast majority of inhaled chemicals. considering large number of chemicals and complex mixtures present in indoor and outdoor air, heavy reliance on animal test methods appear to be not adequate. continuing scientific ...

Oscillations of power systems cause instability in power networks. Power system stabilizer (PSS) is used as a conventional method to damp these oscillations . Finding the optimized gain of PSS is one of the major problems in power system stability issue. In this paper, single machine connected to an infinite bus and 10-machines 39-bus network are considered for study. it's shown that finding th...

A direct Ritz method for solving variational problems with fixed and free boundary conditions is demonstrated. Walsh-hybrid method bases are used as the basis functions. It is shown how the form of the operational matrix of integration affects accuracy of the obtained approximate solutions. The properties of the Walsh-hybrid functions with the operational matrix of integration and the cross pro...