A multilevel control system for the large space telescope

A multilevel scheme was proposed for control of Large Space Telescope (LST) modeled by a three-axis-six-order nonlinear equation. Local controllers were used on the subsystem level to stabilize motions corresponding to the three axes. Global controllers were applied to reduce (and sometimes nullify) the interactions among the subsystems. A multilevel optimization method was developed whereby local quadratic optimizations were performed on the subsystem level, and global control was again used to reduce (nullify) the effect of interactions. The multilevel stabilization and optimization methods are presented as general tools for design and then used in the design of the LST Control System. The methods are entirely computerized, so that they can accommodate higher order LST models with both conceptual and numerical advantages over standard straightforward design techniques

r(8)

Review on r(8) in hematological malignancies with clinical data, structural dynamics and critical genes involved

Survey of indoor concentrations of radon and thoron in homes in Bangalore, India

Due to the legislation and general concern of radiation levels in dwellings in India, there is a need to continuously monitor the indoor concentrations of radon and Thoron in different geographical areas of Bangalore, which could be of great significance to exposure to occupants, particularly in living places. This paper presents the 222Rn and 220Rn concentrations measured in houses in 10 different locations in Bangalore. The data was continuously obtained for a period of 2 years since 2007, covering more than 150 dwellings. The arithmetic mean values of 222Rn and 220Rn were found to be 35.0 and 21.5 Bqm -. The effective dose rate received by the population in the study area ranged between 0.1-0.5 mSv y -1, the arithmetic mean concentration was 0.2±0.03mSv y -1. The result shows no significant radiological risk for the inhabitants. © SAGE Publications 2010

Global Warming - Its Causes & Effects

One of the most current and widely discussed factors, which could lead to the ultimate end of existence of Earth and man, is global warming and its devastating effects. Scientists have asked how fast the Earth is heating up, and how the warming effects on Earth may affect crops and climatic conditions. Several current trends clearly demonstrate that global warming is directly impacting on; rising sea levels, the melting of icecaps, and significant worldwide climatic changes. This article will i) explains the degree of destruction caused by global warming; contributing factors to warming, and ii) discusses what we can do to prevent the rate of increase in global warming

Volumetric Variations of Indoor Radon and Thoron

The volumetric variations of indoor radon and thoron were measured in rooms ranging in volume from 30-310 m 3 in different dwellings at various locations in Bangalore, India. The rooms selected were similar in quality of construction, age, type of walls, and type of floor. Twin cup plastic track detectors were installed in the rooms of 42 dwellings to record indoor 222Rn and 220Rn levels. Higher concentrations were observed in rooms with lower volumes than in rooms with higher volumes. The 222Rn and 220Rn concentrations in the dwellings ranged from 4.0-93.0 Bq m -3, whereas the concentrations of their daughter products ranged from 0.01-2.5 mWL. When the room volume increased tenfold, the concentration of 222Rn reduced by 23 and that of 220Rn reduced by 13, provided all other conditions remained the same. The concentrations did not increase linearly with the volumes of the rooms. The annual effective exposure dose rate because of 222Rn, 220Rn and their daughter products ranged from 0.1-0.4 mSv year -1 with a mean of 0.2 ± 0.1 mSv year -1. © 2011 King Fahd University of Petroleum and Minerals