College of Science

Physical, Biological, Mathematical and Computational Sciences

College of Science Seminars

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Geography Seminar

Understanding Human Dimension of Climate Change Using Participatory Research Technique with Reference to Jharkhand a Newly Created State of India

Wednesday, March 26, 2008 - 2:00pm
Speaker:
Vivek Prasad, PhD student, Environmental Science and Policy George Mason University
Location:
SUB II Ballroom 2Mid

Abstract

Of late, understanding different aspects of human induced Global Climate Change (GCC) has been gaining momentum. GCC is impacting human society on different scales. This impact is more conspicuous and complex to understand when it comes to indigenous and rural community. Almost all aspects of life of these communities are interwoven with the natural processes. Participatory research method is one of the ways to understand the human dimensions of GCC. In this method, stakeholder of the knowledge sharing process is community themselves. Speaker will share his experience working in a newly created state of India; Jharkhand (a land of forest).

[i]The Geography Seminar Series is organized by the Geographical Honors Society Gamma Theta Upsilon Eta Omicron Chapter.[/i]

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ESGS Seminars

Multi-Sensor Satellite Data to Understand Lithosphere-Hydrosphere-Atmosphere Coupling

Wednesday, March 26, 2008 - 4:30pm
Speaker:
Ramesh P. Singh, Department of ESGS/COS/GMU
Location:
Room 301 Building Research I

Abstract

In the last four decades, multi sensor satellites provide information about land, ocean and atmospheric parameters. Earth processes, though complex phenomena, require knowledge of various parameters to understand the strong coupling between Lithosphere-Hydrosphere-Atmosphere which is important to understand various kinds of natural hazards. Physics of remote sensing related with land, ocean and atmospheric parameters associated with earth systems will be discussed.

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Space Sciences Seminar

The role of bulk and thermal Comptonization in producing the time lags observed in X-ray pulsars

Wednesday, March 26, 2008 - 3:00pm
Speaker:
Juan C Luna, George Mason University
Location:
Res. I, Room 301

Abstract

Fourier analysis of X-ray pulsar data reveals the presence of time
lags between hard and soft channels in millisecond pulsars. There is
currently no consistent theoretical explanation for this effect based
on a fundamental physical model for pulsar sources. In the proposed
research, a new theoretical model is developed from first principles
based on the bulk and thermal Comptonization occurring in the gas
inside the accretion column above one (or both) of the magnetic poles
on a rotating neutron star. The model utilizes a combination of
Fourier and Laplace transformation in order to obtain quantitative
predictions for the time lags. This approach will be used to make
predictions about the possible presence of time lags in the spectra of
bright pulsars such as Her X-1. Theoretical interpretation of the time
lags can provide detailed information about the size and properties of
the scattering plasma and also the spatial density profile of the
scattering electrons.

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