the grace mission has provided scientific community time-variable gravity field solutions with high precision and on a global scale. the grace mission was launched on march 2003. this mission consists of two satellites that pursue each other in their orbit. distance between two satellites in orbit is measured continuously to an accuracy of better than 1 micron using kbr system placed in satelli...

Gravity waves are an important driver for the atmospheric circulation and have substantial impact on weather and climate. Satellite instruments offer excellent opportunities to study gravity waves on a global scale. This study focuses on observations from the Atmospheric Infrared Sounder (AIRS) onboard the National Aeronautics and Space Administration Aqua satellite and the Infrared Atmospheric...

As a result of recent developments, global economic centre of gravity has slide to Asia-Pacific region. It is predicted that Asia-Pacific countries will take place at the first row in global trade and nearly a half of the total trade will intensify in this region at the year 2030. On the other hand, the region covers countries from different levels of development. These features of the region p...

We compare new marine gravity fields derived from satellite altimetry with shipboard measurements over a region of more than 120,000 square kilometers in the central South Atlantic. Newly declassified satellite data were employed to construct free-air anomaly maps on 0.05 degree grids [Sandwell and Smith, 1992; Marks et al., 1993]. An extensive gravity and bathymetry dataset from four cruises a...

Coastal Fars gravimetry project in Fars province was carried out to find the buried salt domes and to determine characteristics of faults in this area. The Lavarestan structure was covered by 4203 gravimetry stations in a regular grid of 1000*250 m. Depth structural model of this anticline made in previous studies was based on geological evidences and structural geology measurements. In order t...

We present a technique to fuse inertial and visual information for real-time navigation applications. The combined model exhibits bounded bias, autocalibrates the camera-to-IMU transformation (eliminating the need for precise measurement or construction), and updates an estimate of the gravity vector. We analyze of the observability of the combined system, and discuss the implementation of a fi...

N = 2 closed strings have been recently divided in hep-th/0211147 to two T-dual families denoted by α and β. In (2, 2) signature both families have one scalar in the spectrum. The scalar in the β-string is known to be a deformation of the target space Kähler potential and the dynamics is that of self-dual gravity. In this paper we compute the effective action of the scalar in the α-string. The ...