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Remote piloted aircraft systems (RPAS) have become an important tool for the acquisition of geo-referenced information in agriculture. In particular, this technology can be used for land levelling, making agricultural field surveys more efficient and precise. Due to the above, and the need for high resolution cartography, an evaluation of a prototype of RPAS for topographical surveys, based on georeferenced RGB images, including ground control points, was carried out. To this end, an autonomous flight mission was carried out at the experimental field of the Chapingo Autonomous University, Mexico, at an altitude of 20m, with a horizontal speed of 1m/s and winds of no more than 5 km/h, covering an area of 2151 m² (0.23 ha). The RGB images obtained with the RPAS were corrected by means of ground control points and the dense cloud of points generated was compared with a post-processing GPS topographic survey, obtaining absolute and standard errors of 0.020 and 0.024 m, respectively. [ABSTRACT FROM AUTHOR]

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From the principles of agroecology, design was elaborated an integrated agricultural production at the farm located in the village of Cajete, Popayán, this contributed to the certification process of the agricultural and environmental (AE) program proposed by the intercultural indigenous autonomous University (UAIIN), this process is carried topographic survey soil physicochemical analysis, chemical and microbiological water analysis, evaluation of sustainability of the current production system and proposed implementation technique, projecting the system toward sustainability contributing in the process of education to the communities that make up the UAIIN in resource conservation and recovery of species themselves. [ABSTRACT FROM AUTHOR]

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Geography is a discipline that still in a little use to society and the diferents departments, agencies and public and private entities. However, consistently, more geographers operate vocational and technical agencies to promote local development and consultancy specializing in environmental and territorial issues, among others. This situation is mainly due to deficiencies in the university training system, the absence and/or inefficient management practices for students and lack of technical content to enable students to learn and use techniques and tools that can be applied during subsequent activity work. Brazilian geographer M. Santos proposes an important number of his works to the need to launch out a new way to geography. In his view, it should be useful to society and it should be positioned as a discipline to allow spatial geography. [ABSTRACT FROM AUTHOR]

Buenos Aires City is located on an extensive plain region. The recognition of the geomorphic features in such urbanized environments is especially difficult because they have been smoothed or covered by pavement and buildings. Nevertheless, characterizing and locating the geomorphologic features provides valuable information for the management of many of the environmental problems of the city of Buenos Aires, where floods are the main natural environmental problem. The understanding of geomorphology and drainage systems behavior , is essential for the design of structural building works and for contingency plans that will minimize disruptions and economic loses generated during such events. This paper presents a methodology for the study of the topographical and geomorphic features of the city of Buenos Aires, also replicable in similar urban environments. In these environments the recognition of geomorphic units, based on quantitative, morphometric parameters, is possible when these are obtained from high resolution sources such as cartography to a scale of (e.g. 1:5000) or from photogrametric surveys, that do, however, have numerous interferences in urban areas, resulting less efficient. The current study counted on a significant number of data, an essential requirement to achieve the objective of this work, thanks to the existence of previous, detailed, topographic surveys. The mapping of geomorphic main units and subunits of the city of Buenos Aires, was performed by visual interpretation of morphometric parameters derived from a Digital Terrain Model using Geomatic technologies. The Digital Terrain Model (DTM) was constructed from contours of an equidistance of 1 m, originally produced from a vectorial base of digitally enclosed points with an average density of 3.97 points / ha. The non-linear interpolation method 'non-linear rubber sheeting' was used to construct the DTM, on the base of the aforementioned contours. A shaded relief model was generated (Azimuth: 45°, Sun elevation: 45°), that was useful to qualitatively describe the relief. Slope, aspect, and profile convexity models, which contain morphometric values useful for characterizing the surface, were also constructed. Frequency histograms of the models were sliced to produce discrete classes which were then represented on maps. By superimposing these models, interpreting them visually, and digitalization on-screen, a map of the geomorphic units of the city of Buenos Aires was created. The main geomorphic units identified were the Pampean Plain and the Estuaric Plain. The former was subdivided into: interfluves, valley slopes, flood valleys, while the latter it could be recognized two subunits: Paleoseacliff and the almost flat relief of the Estuaric Plain. The main slope of the city's terrain (E, NE, and SE,with 16.40; 15.90 and 14.79 %, respectively) is related to its underlying structure. The paleoseacliff that separates the Pampean Plain from the Estuaric Plain mainly runs NW-SE, reflecting a similar system of internal tectonic faulting. The maximum and minimum- convexity values coincide respectively with the upper and lower edges of the paleoseacliff. These were located on the DTM at average heights of 14.63 (st. deviation = 2.09) m a.s.l. and 6.20 (st. deviation = 1.71) m a.s.l. .The modal slope value for the city is 0.04°. The paleoseacliff is the subunit with the steepest slope (modal value = 1.06°), followed by valley slopes (modal value = 0.61°), whereas none of the other subunits have a modal value greater than 0.04°. [ABSTRACT FROM AUTHOR]

In this work a system of measure of the topography of objects in axial configuration is implemented. This it is composed of two lens, and photodetectors in arms with confocal working. The object is placed very near the focal plane of the first lens, to the exit of the second lens the beam is split into two paths. A fotodetector is positioned before focal point of the second lens in one paths and in the another after the focal point, of such way that the intensities falling onto each detectors, they can be adjusted to be equal when the object this positioned exactly in the focal plane of the first lens, carried out a design study by means of numeric technical and their results are confronted with some experimental results. Finally the three-dimensional topography of an object is obtained. [ABSTRACT FROM AUTHOR]

The purpose of this study is to present preliminary results of the hydrologic and topographic monitoring of a small stream at the King George Island, Antarctica. Two methods were used in order to measure stream discharge: an area-velocity method using a flow meter and a Parshall flume. Also a topographical survey was made using a total-station theodolite. Great stream discharge fluctuations were identified at the seven stream sections between January 21st and February 13th, 2000. Comparison between 1999 and 2000 topographic survey showed a volumetric decreasing of about 9.450 m3 in one year. This topographic variation could be explained by the erosive capacity of the maximum discharges occurred during the beginning of the austral summer, when a new channel was built. [ABSTRACT FROM AUTHOR]

The modernity and technological changes require that any specialists with out consider their field of knowledge, keep actualizes. By this, the scheme of labor capacities, contained under a project of total quality, support to the institutions, the people, and the education centers to keep itself in the vanguard. These papers show the point of view of the National Institute of Statistics, Geography and Informatics with respect to the Surveying Engineer. [ABSTRACT FROM AUTHOR]

This paper describes the join application of topographical, photogrametrical and satellite (GPS) measurement techniques in the execution of a cadastral surveying. Furthermore, show the characteristics to apply each technique as a function of orography, vegetation, size, location and distribution of the elements to refer in the field; as well as mention the results rich in the application of these techniques in a separate way, and complementation of measurement techniques. [ABSTRACT FROM AUTHOR]

For a long time, geodesists have been discussing which of the height systems is more appropriate for a practical realization of the vertical datum. These discussions are now heating up again in different parts of the world, as individual countries and group of countries are embarking on another wave of modernization of their height networks. This new wave has bean sparked by the advent of GPS ability to measure relatively accurate geodetic height differences. There are two basic concepts of heights that are being seriously considered for adoption in the next of modernization of national height networks. These are the system of orthometric heights or Molodensky's concept of normal heights. In this paper we attempt to throw some light on these to concepts and to answer some of the principal questions arising from the comparison of these two concepts. Both height systems are equally accurate. In our conclusions we present a recommendation that the system of orthometric heights be the one adopted. [ABSTRACT FROM AUTHOR]

The article discusses the benefits of applying an electronic system for the automation of topographical survey. It relates that the system allows to increase the productivity related to topographical surveys and the form of employment such as it saves, time and physical energy for work. It also avoids human errors in the process of gathering data into the computer.