To obtain a good tracking performance in an optical disk drive servo system, it is essential to attenuate periodic disturbances caused by eccentric rotation of the disk. As an effective control scheme for enhancing disturbance attenuation performance, disturbance observers (DOBs) have been successfully applied to the track-following servo system of optical disk drives. In disk drive systems, th...

Abstract The relationships among rangeland management practices and ecosystem on soil nutrient processes are complex. Simulation models can provide valuable insight into this complexity to guide future research decisions for sustainable grazing systems. objective of analysis was evaluate the combinations (continuous vs. rotational), stocking rate (low, moderate, or high), burning (none annual s...

a determination of the genetic variation of the fungus isolated from graminous weeds which is highly beneficial to know probable genetic recombination in the fungus populations was done for the first time in iran through pcr reaction. the isolates of fungus “magnaporthe grisea” from graminous weed hosts and from rice were analyzed through rapd-pcr to assay the mating type and genetic diversity....

This article presents a robust and almost global feedback attitude tracking control scheme in conjunction with a robust deterministic estimator that constructs state estimates for feedback. These control and the estimation schemes use the natural and globally unique representation of rigid body attitude provided by rotation matrices. Attitude and angular velocity state estimates are constructed...

Many local breeds of farm animals have small populations and, consequently, are highly endangered. The correct genetic management of such populations is crucial for their survival. Managing an animal population involves two steps: first, the individuals who will be permitted to leave descendants are to be chosen and the number offspring they will be permitted to produce has to be determined; se...

This paper presents a generic five-axis postprocessor system for various five-axis machine tools. The generalized kinematics model of common five-axis machines is constructed by combining two rotational degrees of freedom on the fixture table and two rotational degrees of freedom on the spindle. The complete analytical equations for NC data are obtained through homogeneous coordinate transforma...

Efficient population transfer by adiabatically chirping through a multiphoton resonance in microwave driven and kicked Rydberg atoms has recently been reported both experimentally and theoretically. Here we report on our simulations in which we have exploited this mechanism to vibrationally excite a diatomic molecule up to |ν = 4, J 〉 from the ground state by chirping through a four-photon reso...

For charged three-body systems, we discuss the configurations and orientations that are admissible for given values of conserved total energy angular momentum. The discussed on a configuration space is reduced by translational, rotational dilation symmetries systems. We consider examples systems helium atom (two electrons nucleus) compound two one positron. comparison, well known example Newton...

mycosphaerella graminicola, the causal agent of septoria tritici blotch (stb), is a widespread and significant pathogen of wheat. to determine mating types, 89 isolates were collected randomly from wheat fields of khuzestan, east azerbaijan, ardebil, kermanshah and golestan provinces of iran, during 2006-7. dna was extracted based on standard protocols. multiplex pcr was conducted using two pai...