USE OF MERCATOR CARTOGRAPHIC REPRESENTATION FOR LANDSAT 8 IMAGERIES

Nowadays Marine Geographical Information Systems (MGIS) play an essential role in several research activities, the most part of them related to solve Geoscience problems. The nautical maps, containing most of the information used by the marine navigators, are used as cartographic base of MGIS and widely referred to Mercator projection. Remotely sensed images can be introduced in MGIS to improve the study outcomes even if they are in a different cartographic representation (generally Universal Transverse of Mercator, UTM). The adaptation of already georeferred remotely sensed images to Mercator projection requires particular care, moreover when also geodetic data are different (i.e. local datum and global datum). This paper is aimed to offer an easy-to-use work-flow that could be adopted every time remotely sensed images are to be introduced in MGIS and overlaid to nautical maps. Particularly the work addresses the implementation and evaluation of reprojection of Landsat 8 imageries, regarding both the gulfs of Naples and Salerno (Italy): a transformation from UTM WGS84 to Mercator Roma40 is applied. The result accuracy encourages the adoption of the proposed work-flow

BATHYMETRY FROM WORLDVIEW-3 SATELLITE DATA USING RADIOMETRIC BAND RATIO

The use of optical satellite sensors allows to obtain bathymetry data on large area ina short time and in a cheap way. In addition, in particular places where it is difficult to carry out the survey by classic methods, the bathymetry from satellite data can be the only mode to obtain the depth of the backdrop. So, the aim of this research paper is to analyse the potential of the eight bands and the very high resolution of the commercial satellite WorldView-3 (WV-3) in order to obtain bathymetric data. Using WV-3 satellite data and the Stumpf method, the paper intends to investigate the possibility of obtaining bathymetric data in a specific area where the water is not particularly clear. To achieve this goal, in Geographic Information System (GIS) environment, several algorithms have been developed. The comparison between the results and the reference bathymetric data shows a huge potential of the WV-3 satellite data. The area of study concerns the port area of the city of Lisbon and a part of the river Rio Tejo, in Portugal

High Resolution Satellite Images to Reconstruct Recent Evolution of Domitian Coastline

In the last decades, combinations of natural and human factors have resulted in extensive morphological changes to our coastlines and in many cases have amplified erosion. In order to limit these changes and their impact on coastal zone, it is important to plan specific actions; for this purpose detailed cognizance of coastal zone is necessary. Different and heterogeneous data such as historical and recent maps, remotely sensed images and topographic survey result very useful to reconstruct temporal shoreline changes. In this study the attention is focalized on Domitian coastal zone (Italy), which is one of the most emblematic examples of coastal erosion in Europe. Study of the shoreline evolution in this area between 1876 and 2005 was used as the starting point of the present paper that investigates over a span of seven years (2005 to 2012), by using remotely sensed data. The aim is to adapt and integrate geomatics techniques to transform very high resolution satellite images in powerful tools to analyse coastline changes. So, in order to identify eroded and added areas, IKONOS-2 (2005), GeoEye-1 (2011) and WorldView-2 (2012) imageries are compared. These data-sets were re-georeferred to improve the positional accuracy. More over Normalized Difference Water Index (NDWI) was applied to pan-sharpened multispectral images to facilitate coastline vectorising at the same geometric resolution of panchromatic data. In addition, variance propagation was considered to establish the accuracy of the reconstruction of coastal evolution. Added and eroded areas were defined and related to the impact of the defence structures that were built in this zone in 2011

Coastline extraction using high resolution WorldView-2 satellite imagery

AbstractThe aim of this paper is to remark possibilities to use WorldView-2 imagery for coastline extraction. Applications are conducted on a Phlegrean area in the Campania Region (Italy): the considered range of coastline is particularly interesting because it shows two typologies of shoreline including reefs interspersed with segments of sandy beach. Two indices are used: Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI).To enhance geometric resolution of the results pan-sharpening is applied so as to obtain maps with the same pixel dimensions of the panchromatic data. To solve the problem of thresholds determination that typically affects the classification, Maximum Likelihood method based on training sites is adopted to distinguish bare soil and sea water. Best results are given by NDWI and, comparing the resultant coastline with that obtained with visual interpretation of images, shifts of less than 1 m outcome from pan-sharpened data

Increasing Geometric Resolution of Data Supplied by Quickbird Multispectral Sensors

On board of Quickbird satellite two types of sensors are present: panchromatic and multispectral. The first acquires earth images within spectral range 0.405 mm - 1.053 mm; the second acquires simultaneously four images of the same scene, each of them within shorter range of spectrum (Blue, Green, Red, Near-Infrared). Panchromatic images present geometric resolution 0.60 m while multispectral ones 2.40 m. For many applications, detailed data are welcome, so in the last decades several methods have been elaborated in Remote Sensing to transfer pixel dimensions of pan images into multispectral images. Included in data fusion techniques, they are named pan-sharpening methods and one of the principal problems they are called to resolve is to define weights to attribute to each multispectral component in fusion operations. The aim of this paper is to consider the application to Quickbird imagery of two efficient pan-sharpening methods, IHS and Brovey transformation, demonstrating that multispectral weights can be easily derived by analysis of sensors relative spectral radiance response

Orthorectification and Pan-Sharpening of WorldView-2 Satellite Imagery to Produce High Resolution Coloured Ortho-Photos

In the last decade VHR (Very High Resolution) images from satellite, because of the reduced dimensions of pixel (less than 1 meter) and the availability in different acquisition bands (4 or more), have had major dffusion in many application fields of remote sensing. They can be used also to produce high resolution coloured ortho-photos, but adequate levels of positional accuracy as well as small pixel dimensions are necessary. The aim of this paper is to demonstrate that WorldView-2 (WV-2) images satisfy totally these requirements if firstly submitted to high accurate rectification and Pan-Sharpening processes. Using Rational Polynomial Functions (RPFs), original dataset can be better overlapped to cartographic maps at medium or great scale; multispectral images (cell size: 2 m) can be resampled to meet geometric resolution of pan one (cell size: 0.5 m), so detailed and attendible RGB composition results. Applications are carried out on one sample of WV-2 imagery concerning a scene within the Province of Caserta (Italy) that includes vegetated as well as urban areas. Finally RGB composition with pixel dimensions of 0.5 m, positional accuracy less than 1 meter and likely colors are achieved, confirming the possibility to use this type of images for coloured ortho-photos at scale 1:5.000 at least

Global geoid adjustment on local area for GIS applications using GNSS permanent station coordinates

Orthometric heights, useful for many engineering and geoscience applications, can be obtained by GPS (Global Positioning System) surveys only when an accurate geoid undulation model (that supplies the vertical separation between the geoid and WGS84 ellipsoid) is available for the considered topic area. Global geoid height models (i.e., EGM2008), deriving from satellite gravity measurements suitably integrated with other data are free available on web, but their accuracy is often not sufficient for the user’s purposes. More accurate local models can nevertheless be acquired, but often only for a fee. GPS/levelling surveys are suitable for determining a local, accurate geoid model, but may be too expensive. This paper aims to demonstrate that GNSS (Global Navigation Satellite System) Permanent Station documents (monographs), freely available on the web and supplying orthometric and ellipsoidal heights, permit to calculate precise geoidal undulations useful to perform global geoid modelling on a local area. In fact, in this study 25 GNSS Permanent Stations (GNSS PS), located in North-Western Italy are considered: the differences between GNSS PS geoidal heights and the corresponding EGM2008 1′ × 1′ ones are used as a starting dataset for Ordinary Kriging applications. The resulting model is summed to the EGM2008 1′ × 1′, obtaining a better-performed model of the interest area. The accuracy tests demonstrate that the resulting model is better than EGM2008 grids to produce contours from a GPS dataset for large-scale mapping

O Diferencial do Constituinte Cearense na Criação do Conselho Estadual de Justiça

This article reflects on the creative and innovative spirit of the constituent of Ceará, which had the bold initiative to create a state body for external control of the Judiciary during the 1989 Constituent Assembly.Este artigo faz uma reflexão acerca do espírito criativo e inovador do constituinte cearense, que teve a iniciativa ousada de criar um órgão estadual de controle externo do Poder Judiciário durante a Assembléia Estadual Constituinte de 1989

Historical review of neutron spectrometry and diffraction in Brazil – 50 years

Neutron Spectrometry and Diffraction techniques began to be studied in Brazil with the construction of the first research reactors in the years 50 and 60, and were developed with the participation of national and international scientists. In particular, we note the perseverance of the Brazilian pioneer of nuclear energy, Dr. Marcello Damy de Souza Santos_, and from that time, with the involvement of some of the early pioneers, such as the physicist Roberto Stasiulevicius_, who had the privilege of working in all three Brazilian nuclear research reactors. All these scientists shared half a century of acquired knowledge, helping in the training of a number of experts who are now working in national and international nuclear institutes. The present work reviews in chronological order, the testimony of the historical facts associated with the development and application of experimental techniques using neutrons as a tool for materials analysis and studies for many areas of the sciences and also with the training of personnel. IPEN, IEN and CDTN, all institutes of the CNEN-Brazil, are important in the national and international scene as a result of the research carried out there and the large number of publications produced in the field of neutron spectrometry and diffraction from experimental work carried out using the IEA (5MW), Argonauta (5kW) and more recently, the IPR (250kW) research reactors. An extensive bibliography is also presented and this can be disseminated to everyone interested