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We have synthesized magnetic nanoparticles using the newly developed sonomechanical method with the FeSO 4 . 7H 2 O and characterized crystallographic structural changes, surface morphology, chemical bonding states and magnetic properties. The crystallographic structure of the nanoparticles was characterized with high resolution X-ray powder diffraction (XRD) analysis. The surface morphology of the nanoparticles was observed by scanning electron microscopy. The chemical bonding states of Fe ions in the nanoparticles were examined by X-ray photoelectron spectroscopy (XPS) analysis. The magnetic properties of the nanoparticles were analyzed with vibrating sample magnetometer at room temperature. The XRD patterns and XPS spectra indicated that the synthesized nanoparticles were mixture of magnetite (Fe 3 O 4 ) and maghemite ( -Fe 2 O 3 ). As varying post annealing temperature, it seems that there was occurred transition to magnetite to maghemite and maghemite to magnetite.

Several studies have been performed globally on the construction of integrated systems that are available for the integrated use of 3D geographic information on terrain and oceans. Research on 3D geographic modeling is also facilitated by the

This paper describes an analysis of topographical changes to the Eulsuk-Island at the Nakdong River Estuary using a long-term dataset of high resolution aerial images from 1983 to 2007. Ground control surveying was performed at some feature points using GPS(Global Positioning System) to accomplish AT(Aerial Triangulation) for past aerial images. Even if some still existing feature points appeared on old aerial images were used as GCPs(Ground Control Points) for past aerial images in AT, its accuracy reached at 1m level. Since then, a quantitative analysis of topographical changes was conducted on digital orthophotos produced by a series of aerial images taken by different years. The change volume of total area, construction, vegetation, buildings and roads could be extracted per each period in study area. The total area decreased from 1983 to 1992, but it has not almost changed since 1992. According to the continuous development, the area of vegetation has steadily decreased, while that of buildings and roads has generally increased. The result of this study can provide us with invaluable base data for further topographical change monitoring in Eulsuk-Island and Nakdong River estuary caused by continuous development in this area.