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The purpose of this paper is to estimate quick and low-cost processes for surface runoff potential on the basis of natural environmental attributes.

An approach based on the natural environmental attributes and on the Cook’s method was used for maximal peak flows of surface runoff, as well as for assigning weights to the considered attributes. Used attributes are as follow: steepness, bedrock (lithology), soil (texture, genesis, thickness, and permeability coefficient), drainage density, and favorable features to surface storage.

Using natural environmental attributes from previous available studies, adapted from different scales, the authors obtain a low-cost potential surface runoff chart, which can be useful for planning, impact and hazard analysis, and decision purposes in an area without large financial resources, like small communities in developing countries. Despite the common scarcity of data in these communities, often regional basic studies of soil and bedrock are available, making this kind of analysis possible.

The highlights are quick and low-cost procedures in characterizing the natural environment for planning activities, providing the basis for further detailing, which focus on solving local problems. This approach to runoff estimation allows for the definition of the criteria, considering the potential geodynamic processes. Thus, this kind of study may be very useful for land use planning in developing countries.

The purpose of this paper is to present an adaptive finite element procedure that improves the quality of convection dominated mid‐ocean ridge (MOR) and subduction zone (SZ) simulations in geodynamics.

The method adapts the mesh automatically around regions of high‐solution gradient, yielding enhanced resolution of the associated flow features. The approach utilizes an automatic, unstructured mesh generator and a finite element flow solver. Mesh adaptation is accomplished through mesh regeneration, employing information provided by an interpolation‐based local error indicator, obtained from the computed solution on an existing mesh.

The proposed methodology works remarkably well at improving solution accuracy for both MOR and SZ simulations. Furthermore, the method is computationally highly efficient.

To date, successful goal‐orientated/error‐guided grid adaptation techniques have, to the knowledge, not been utilized within the field of geodynamics. This paper presents the first true geodynamical application of such methods.

This paper aims to describe two Web-based technologies of geographic information systems (GIS) to be used in monitoring and analysis of environmental processes, proposed by the authors. The technologies analyze the temporal aspect of the process together with the spatial aspect, which defers them from most other works on environmental processes, as these are usually limited either to spatial statistics or to temporal statistics. The approach is instrumental in dynamically finding the relationships between the processes and predicting critical incidents.

Often, the study of natural processes is limited to the analysis of their spatial properties presented by individual time series. The principal idea of this approach consists in supplementing this traditional analysis with the analysis of time fields. In this way, the authors are able to analyze temporal and spatial properties of environmental processes together.

The paper presents two technologies which provide the analysis of spatial and temporal data obtained in natural environment monitoring. The discussed spatio-temporal data mining methods are shown to enable the research into environmental processes, and the solution of practical issues of critical situation forecasts.

The paper discussed Web-based GIS technologies for the analysis of the temporal aspect of the environmental process together with the spatial aspect. Application examples demonstrate the ability of this approach to find the relationships in dynamics of the processes and to predict critical incidents.

Earthworks are the embankments and cuttings that allow a railway to maintain a certain line, level and grade through the landscape. Earth embankments consist of an engineered bank of earth that carries the railway above the natural ground. A cutting is used to carry the railway through ground with a natural level above the line of the railway. Modern (post 1960s) earthworks are carefully engineered to perform well. However, many railways run on earthworks that were constructed over 100 years ago without the use of mechanised plant. The quality of construction of older earthworks was often poor compared with present-day engineering practice. Ageing of the earthwork structures, and the greater demands of heavier and faster trains and climatic change, means that earthworks suffer ultimate and serviceability failures that can present operational difficulties. Older earthworks that fail or do not perform well require maintenance and repair, and sometimes complete replacement. This chapter explores the main engineering considerations for modern earthworks, and the challenges associated with older earthworks including their modes of failure and upgrade and repair.

This paper aims to provide a method for obtaining physically sound temperature fields to be used in geophysical inversions in the presence of immersed essential conditions.

The method produces a thermal field in agreement with a given location of the interface between the Lithosphere and Asthenosphere. It leverages the known location of the interface to enforce the location of a given isotherm while relaxing other constraints known with less precision. The method splits the domain: in the Lithosphere the solution is immediately obtained by standard procedures, while in the Asthenosphere a minimization problem is solved to fulfill continuity of temperatures (strongly imposed) and fluxes at the interface (weakly imposed).

The numerical methodology, based on the relaxation of the bottom fluxes, correctly recovers the thermal field in the complete domain. To obtain bottom fluxes following geophysical expected values, a constrained minimization strategy is required. The sensitivity of the method could be improved by relaxing other quantities such as lateral fluxes or mantle velocities.

A statement of the energy balance problem in terms of a known immersed condition is presented. A novel numerical procedure based on a domain-splitting strategy allows the solution of the problem. The procedure is tailored to be used within geophysical inversions and provides physically sound solutions.

This paper reports on the successful introduction of a sophisticated online catalogue system at the library of the Scott Polar Research Institute, Cambridge, using the Muscat program package. The system provides to both end‐users and library staff a choice between boolean searching on keywords and access using relevance feedback based on free text in English, mixed with UDC classification numbers. The system is implemented on an IBM 3084 computer. Significant benefits from the application of relevance feedback are reported with 10,000 records on file.

The purpose of this case study is to indicate discrepancies between the guidelines for aeronautical data quality requirements (DQR) and the legal regulations of surveying in Poland. Because of the possible difficulties in determining the original source of geodetic coordinates, it is possible for mistakes to be made, e.g. in aeronautical metadata.

The differences between selected reference data for the ASG-EUPOS network stations were determined and later extended to the entire country using the linear interpolation method. The values were investigated for exceeding the most restrictive limit on the DQR, i.e. 0.50 m for geodetic latitude and longitude and 0.25 m for measured height and geoid undulation.

The lack of an appropriate transformation of geodetic coordinates would result in an error of 0.30 m for the horizontal position, and <0.01 m for ellipsoidal heights. The discrepancies between the Earth Gravitational Model 96 (EGM96) geoid model used in aviation and Polish local quasigeoid model are up to 1 m.

Results prove that a mismatch of coordinate frames could be a severe threat to the aeronautical DQR. Providing complete information about reference systems during the data exchange, including the conversion parameters between selected geoid models, or considering a more accurate geoid model as a reference in aviation is recommended.

To the best of the author’s knowledge, this study is perhaps the first to compare data quality guidelines for surveying and aviation.

Cylindrical components are common in industry assembly areas. It is necessary to obtain their precise positions and orientations for their assemblies. But some measurement approaches relying on measuring targets are not allowed, as they may not meet the efficiency requirement of on-line measurement or may cause surface damages to the components. Thus, this paper aims to provide a precise on-line non-target scanning method based on 3D vision.

First, a laser profile sensor is used to acquire point cloud of the side surface of the measured cylindrical component. Then a composite process is conducted to estimate the pose and position of the axis. Aiming at this purpose, two fitting approaches, i.e., axis fitting and generatrix fitting, are tried respectively to estimate the pose parameters from the point cloud.

The results of Monte Carlo simulations demonstrate that neither the axis fitting nor the generatrix fitting could solely obtain the needed accuracy and precisions roundly. Thus, a new synthesis method is presented. And the results of prototype experiments validate the excellent accuracy and precision of the synthesis method.

This proposed new synthesis method combines the advantages of both the above fitting methods and can be easily integrated into the assembly line to guide the automation assembly process of the cylindrical components precisely.

In order to improve the robustness to noise in point cloud plane fitting, a combined model of improved Cook’s distance (ICOOK) and WTLS is proposed by setting a modified Cook’s increment, which could help adaptively remove the noise points that exceeds the threshold.

This paper proposes a robust point cloud plane fitting method based on ICOOK and WTLS to improve the robustness to noise in point cloud fitting. The ICOOK to denoise the initial point cloud was set and verified with experiments. In the meanwhile, weighted total least squares method (WTLS) was adopted to perform plane fitting on the denoised point cloud set to obtain the plane equation.

(a) A threshold-adaptive Cook’s distance method is designed, which can automatically match a suitable threshold. (b) The ICOOK is fused with the WTLS method, and the simulation experiments and the actual fitting of the surface of the DD motor are carried out to verify the actual application. (c) The results shows that the plane fitting accuracy and unit weight variance of the algorithm in this paper are substantially enhanced.

The existing point cloud plane fitting methods are not robust to noise, so a robust point cloud plane fitting method based on a combined model of ICOOK and WTLS is proposed. The existing point cloud plane fitting methods are not robust to noise, so a robust point cloud plane fitting method based on a combined model of ICOOK and WTLS is proposed.