Selection Of Control Points Research Articles

Control Point Selection for Dimensionality Reduction by Radial Basis Function

This research deals with dimensionality reduction technique which is based on radial basis function (RBF) theory. The technique uses RBF for mapping multidimensional data points into a low-dimensional space by interpolating the previously calculated position of so-called control points. This paper analyses various ways of selection of control points ( regularized orthogonal least squares method, random and stratified selections). The experiments have been carried out with 8 real and artificial data sets. Positions of the control points in a low-dimensional space are found by principal component analysis. We demonstrate that random and stratified selections of control points are efficient and acceptable in terms of balance between projection error ( stress ) and time-consumption. DOI: 10.15181/csat.v4i1.1095

Simulation and optimization of groundwater exploitation for the water supply of Tarnów agglomeration (southern Poland)

This paper presents the application of the simulation-optimization approach to optimize groundwater intake for water supply of Tarnow agglomeration. Tarnow agglomeration is supplied with water from extensively exploited surface and groundwater intakes located at the confluence of the rivers Dunajec and Biala. Groundwater intakes capture water from the Quaternary aquifer, which is recharged by rainfall and direct infiltration from the rivers and irrigation ditches. Hydrogeological conditions occurring within the area under consideration were mapped by using a single-layer numerical model in Processing Modflow software. After calibrating the simulation model, a simulation-optimization approach was developed in the aim to aid the process of searching the best scheme of exploitation of groundwater intake. The unit response matrix method was used to connect the simulation model with the optimization procedure. In the optimization task the objective functions concerning the total volume of groundwater intake discharge and infiltration amount from Dunajec river or irrigation ditches were applied. Several constraints concerned both the maximum and minimum capacity of individual wells and entire intake, as well as desirable or undesirable drawdown values in selected control points and control areas. Finally, twelve variants of optimization tasks, for different boundary conditions and different objective functions, were solved and optimal schemes of well discharge distribution within the intake were calculated. The results of optimization show that, depending on the intended objective and the constraints imposed, the best exploitation scenario under the given conditions may be found.

Simulation and optimization of groundwater exploitation for the water supply of Tarnów agglomeration (southern Poland)

Abstract This paper presents the application of the simulation-optimization approach to optimize groundwater intake for the water supply of Tarnów agglomeration (southern Poland). Tarnów agglomeration is supplied with water from extensively exploited surface and groundwater intakes located at the confluence of the rivers Dunajec and Biała. Groundwater intakes capture water from the Quaternary aquifer, which is recharged by rainfall and direct infiltration from the rivers and irrigation ditches. Hydrogeological conditions occurring within the area under consideration were mapped by using a single-layer numerical model in Processing Modflow software. After calibrating the simulation model, a simulation-optimization approach was developed with the aim of aiding the process of searching for the best scheme of exploitation of groundwater intake. The unit response matrix method was used to connect the simulation model with the optimization procedure. In the optimization task the objective functions concerning the total volume of groundwater intake discharge and infiltration amount from the River Dunajec or irrigation ditches were applied. Several constraints concerned both the maximum and minimum capacity of individual wells and the entire intake, as well as desirable or undesirable drawdown values in selected control points and control areas. Finally, twelve variants of optimization tasks, for different boundary conditions and different objective functions, were solved and optimal schemes of well discharge distribution within the intake were calculated. The results of optimization show that, depending on the intended objective and the constraints imposed, the best exploitation scenario under the given conditions may be found.

Research on Reconstruction of Edge for Three-Dimensional Model Using Behavior Restriction

Based on the analysis of the radial basis function (RBF) implicit surface reconstruction algorithm, an adaptive behavior control constrained reconstruction algorithm is proposed including point selection, the local two surface constraints, behavior selection of control points, and the radius of influence identified key links in detail. The validity of the algorithm is demonstrated on examples and shortcomings of exited algorithm by comparing. Finally the direction of improvement are analyzed and pointed out in the future.

Extracting ecological information from oblique angle terrestrial landscape photographs: Performance evaluation of the WSL Monoplotting Tool

While aerial photography and satellite imagery are the usual data sources used in remote sensing, land based oblique photographs can also be used to measure ecological change. By using such historical photographs, the time frame for change detection can be extended into the late 1800s and early 1900s, predating the era of aerial imagery by decades. Recent advancements in computing power have enabled the development of techniques for georeferencing oblique angle photographs. The WSL Monoplotting Tool is a new piece of software that opens the door to analyzing such photographs by allowing for extraction of spatially referenced vector data from oblique photographs. A very large repeat photography collection based on the world's largest systematic collection of historical mountain topographic survey images, the Mountain Legacy Project, contains >6000 high resolution oblique image pairs showing landscape changes in the Rocky Mountains of Alberta between ca. 1900 – today. We used a subset of photographs from this collection to assess the accuracy and utility of the WSL Monoplotting Tool for georeferencing oblique photographs and measuring landscape change. We determined that the tool georeferenced objects to within less than 15 m of their real world 3D spatial location, and the displacement of the geographic center of over 121 control points was less than 3 m from the real world spatial location. Most of the error in individual object placement was due to the angle of viewing incidence with the ground (i.e., low angle/highly oblique angles resulted in greater horizontal error). Simple rules of control point selection are proposed to reduce georeferencing errors. We further demonstrate a method by which raster data can be rapidly extracted from an image pair to measure changes in vegetation cover over time. This new process permits the rapid evaluation of a large number of images to facilitate landscape scale analysis of oblique imagery.

Special issue: terrestrial remote sensing for areal deformation monitoring

The development of new instruments, sensing techniques, and algorithms has opened a new era in the field of terrestrial deformation monitoring and related applications. Robotic total stations with reflector-less range measurement and increasingly also image assistance (Scherer and Lerma 2009), terrestrial laser scanners (Vosselman and Maas 2010), and digital photogrammetry (Barazzetti et al. 2010) allow the acquisition of dense point clouds within a short time, thus yielding detailed snapshot representations of surfaces and a basis for measuring deformations over wide areas. In addition, ground-based interferometric radar (Monserrat et al. 2014) can be used to derive differential deformation with very high resolution, in particular with respect to persistent scatterers as discussed already by Ferretti et al. (2001). The amount of data provided by these systems is typically much larger than with traditional geodetic techniques, and they potentially represent areal deformations without a need for generalization from displacements of a few carefully selected control points. However, there is no direct point-topoint correspondence between the point clouds obtained at different epochs and thus entirely new algorithms are required in order to analyze deformations (see Dermanis (2011) and Fuentes Santibanez (2012)). New concepts for areal deformation monitoring (ADM) are being developed and investigated including instrumental advances, sensor and process models, and data processing techniques. All of these require thorough validation and assessment before they can be safely applied in critical monitoring applications. This special issue features six selected contributions originally presented at the 2nd Joint International Symposium on Deformation Monitoring (JISDM) held in Nottingham on September 2013 and subsequently further elaborated for peer review and publication. They introduce new instrumental developments, compare technologies and review the state-ofthe-art with respect to their impact on areal deformation measurements, and propose new methods for deformation analysis. The affiliations of the authors of these papers are located in different countries across the globe (Germany, Greece, Italy, the Netherlands, People’s Republic of China, Switzerland, the UK), highlighting internationally recognized relevance of research into areal deformation monitoring. The first article in the special issue (Papastamos et al. 2015) describes the application of total stations for the measurement of control point 3-D displacements with nearly millimeter accuracy. During a project for the excavation of the Athens underground metro railway, this technique was exploited to assess tilting of some chimneys resulting from ground deformation due to tunneling. While such deformations are usually assumed as a 2-D effect, here the theodolite measurements pointed out the evidence of clear 3-D rigid movements of the chimneys in different directions. This outcome was in full agreement with the new theoretical models of ground deformations in the investigated area. * Alessandro Capra capra.alessandro@unimore.it

Automatic registration and mosaicking of technical images of Old Master paintings

The registration of technical art conservation images of Old Master paintings presents unique challenges. Specifically, X-radiographs and reflective infrared (1000–2500 nm) images reveal shifted, or new, compositional elements not visible on the surface of artworks. Here, we describe a new multimodal registration and mosaicking algorithm that is capable of providing accurate alignment of a variety of types of images, such as the registration of multispectral reflective infrared images, X-radiographs, hyperspectral image cubes, and X-ray fluorescence image cubes to reference color images taken at high spatial sampling (300–500 pixels per inch), even when content differences are present, and a validation study has been performed to quantify the algorithm’s accuracy. Key to the algorithm’s success is the use of subsets of wavelet images to select control points and a novel method for filtering candidate control-point pairs. The algorithm has been used to register more than 100 paintings at the National Gallery of Art, D.C. and The Art Institute of Chicago. Many of the resulting registered datasets have been published in online catalogues, providing scholars additional information to further their understanding of the paintings and the working methods of the artists who painted them.

Selection and allocation of manual traffic control points and personnel during emergencies.

Manual traffic control is an intersection control strategy in which law enforcement officers allocate intersection right-of-way to turning movements. Many emergency traffic management plans call for manual traffic control in response to oversaturated roadway conditions. This is because it is thought to more effectively move traffic during temporary surges in demand. The goal of this research was to evaluate the current state-of-the-practice used by the Army Corps of Engineers (ACE) in selecting intersections for manual traffic control and allocating police personnel to them during emergencies. This research uses the emergency traffic management plans developed by the ACE for nine counties in the Maryland Eastern Shore region. This area encompassing 14,318 intersections of which 74 were selected for manual traffic control during emergencies. This work sought to quantify the correlations that exist between intersection attributes and the ACE' decision to allocate officers to control them. The research findings suggest that US routes, State routes, and emergency evacuation routes are statistically significant in determining the need for police control at intersections. Also significant are intersection on contraflow corridors and intersections near grade separated interchanges. The model also determined that intersections isolated from evacuation routes and county exits were more likely to be selected for manual control, indicating that rural areas may rely on manual traffic control in the absence of multilane highway and freeways. This research also found that intersections involving evacuation routes, contraflow corridors, and grade separated interchanges may warrant additional police personnel (two or more officers) for manual traffic control.

Feature Point Selection using Structural Graph Matching for MLS based Image Registration

Image registration is a method of determining a mapping or a transformation that relates positions in one image, to the corresponding positions in the other images under considerations. The process of registration depends on the homologous control points that are selected from the source and the target images. This paper focuses on the use of the structural information of an image, for selecting control points, as it remains the same even when it undergoes most of the transformation and illumination changes. The points thus obtained are then given to the Moving Least Squares (MLS) based registration technique reported earlier by the authors [11].

Rectification control points selection method of triangle mesh in optical pressure measurement of wind-tunnel test.

In optical pressure measurement of wind-tunnel test, triangle mesh is usually built to rectify the images that are distorted in geometry. In this paper, a novel method of control points selection of triangle mesh is proposed by combining the artificial points and margin control points. For the problem that in the condition of wind the margin control point is difficult to extract due to model distortion and grey variation, an improved Smallest Univalue Segment Assimilating Nucleus algorithm based on region selection and adaptive threshold is designed. The connection method is employed to verify the availability of points, which avoids that the noisy points are mistakenly regarded as the angular points. The distorted images of aircraft model are rectified and the results are analyzed. Experiments demonstrate that the proposed method greatly improves the rectification effect.

Uncertainty Segregation and Comparative Evaluation in Groundwater Remediation Designs: A Chance-Constrained Hierarchical Bayesian Model Averaging Approach

Groundwater remediation designs rely on simulation models that are subjected to various sources of uncertainty. This study introduces a hierarchical Bayesian model averaging (HBMA) method to segregate sources of uncertainty in a hierarchical order and conduct comparative evaluation of BMA models for remediation designs. A BMA tree of models is developed to understand the impact of individual sources of uncertainty in the remediation design. The HBMA method is applied to chance-constrained (CC) formulation for an aquifer remediation design that aims to reduce concentration at a selected control point using scavenger wells. Thirty-six (36) flow and transport models for concentration prediction are developed to analyze the impact of three sources of uncertainty on the remediation design. An essential step in HBMA is to calculate posterior model probabilities as model weights. The best simulation model has the highest model weight. The results show that although using the best simulation model requires the least pumping rate for the scavenger well, it underestimates prediction variances of concentration. The scavenger well pumping rate increases as more sources of uncertainty are considered. The HBMA enables the chance-constrained formulation to consider both model parameter and model structure uncertainties for aquifer remediation designs. The contributions of prediction variance from individual sources of uncertainty to the total prediction variance can be evaluated, which provides an understanding of the impact of individual sources of uncertainty and their corresponding propositions on remediation designs.

Processing and Mosaicing System of Civil Unmanned Aerial Vehicle Remote Sensing Image

With combining Unmanned Aerial Vehicle (UAV) and the high-precision of the low altitude Remote Sensing (RS) technology, UAV RS technology has become an important compleme-nt for satellite and manned aircraft RS, so it has drawn great attention of people at home and abroad. Most of UAV RS image technologies use small digital cameras to shoot so that it causes some proble-ms such as lower magnitude, more and larger morphing image. The image processing and mosaicing system of UAV RS implements the function of image identifying, selection of image group control points, geometric correction, mosaicing, seam lines eliminating automatically and rapidly with Interactive Data Language (IDL), and is targeted to solve the practical application problems such as preprocessing, mosaicing, seam-lines removing of civil UAV RS image.

Approximating odd degree Bézier pieces by degree-elevation cutdown polygons

Cutdown polygon, constructed by directly connecting some selected control points of the Bézier piece, is proposed for Bézier piece approximation by Zhang and Ma. However, for Bézier piece with odd degree, there are multiple solutions for selecting control points of cutdown polygon. In this note we propose to approximate odd degree Bézier piece by a unique cutdown polygon of its degree-elevation Bézier piece, i.e. its degree-elevation cutdown polygon. The degree-elevation cutdown polygon has the same edge number as original cutdown polygon, but has sharper error bound.

Sea Ice Motion Tracking From Sequential Dual-Polarization RADARSAT-2 Images

A new sea ice motion tracking algorithm that operates with two sequential synthetic aperture radar (SAR) RADARSAT-2 ScanSAR images is presented. The feature tracking approach is based on the combination of the phase-correlation and cross-correlation methods. An algorithm for selecting control points, a matching technique, an approach for filtering out error vectors, and a confidence levels setting for output drift vectors were specifically developed in order to increase the system's robustness and accuracy. We evaluated ice motion tracking results derived from HH and HV channels of RADARSAT-2 ScanSAR imagery and formulated a condition where the HV channel is more reliable than the HH channel for ice tracking. Furthermore, we found that the ice motion tracking from the HV channel is not affected by noise floor stripes, which are prominent in the cross-polarization RADARSAT-2 ScanSAR images. The developed sea ice tracking technology was implemented at the Canadian Ice Service, Environment Canada for operational use. The system was successfully run to provide operational support of field work in the Arctic Ocean in compliance with the United Nations Convention on the Law of the Sea in the spring of 2010.

CONTOURS BASED APPROACH FOR THERMAL IMAGE AND TERRESTRIAL POINT CLOUD REGISTRATION

Abstract. Building energetic performances strongly depend on the thermal insulation. However the performance of the insulation materials tends to decrease over time which necessitates the continuous monitoring of the building in order to detect and repair the anomalous zones. In this paper, it is proposed to couple 2D infrared images representing the surface temperature of the building with 3D point clouds acquired with Terrestrial Laser Scanner (TLS) resulting in a semi-automatic approach allowing the texturation of TLS data with infrared image of buildings. A contour-based algorithm is proposed whose main features are : 1) the extraction of high level primitive is not required 2) the use of projective transform allows to handle perspective effects 3) a point matching refinement procedure allows to cope with approximate control point selection. The procedure is applied to test modules aiming at investigating the thermal properties of material.

Edge directed automatic control point selection algorithm for image morphing

Image morphing is a technique used for the metamorphosis of one image to another. In order to do morphing, new positions (control points) for the pixels in each of the images must be determined. The control point selection is a difficult process that is conducted manually in most cases, which is time consuming and lacks accuracy. In this research, we propose an Edge Directed Automatic Control Point Selection algorithm that uses Canny Operator to detect edges and a Central Axis-based Partition method to establish the correspondence between the source and the target images. Experimental results show that the proposed low complexity algorithm performance is better than that of a manually chosen point selection method in terms of both accuracy and time.

A kernel-free boundary integral method for implicitly defined surfaces

The kernel-free boundary integral (KFBI) method is a structured grid method for general elliptic partial differential equations. Unlike the standard boundary integral method, it avoids direct evaluation of volume and boundary integrals, which needs to know analytical expressions for the integral kernels. To evaluate a boundary or volume integral, the KFBI method first solves a corrected interface problem on a structured grid and then the numerical solution on the structured grid is interpolated to get approximate values of the integral at points on the boundary. Selection of control points of the boundary plays a key role in the KFBI method since both the correction for the interface equations and the interpolation with the structured grid based solution involve calculation of tangential derivatives of boundary data while stability and efficiency of the numerical differentiation critically depend on the distribution of control points. This work proposes a new point selection method, based on an overlapping surface decomposition of the boundary, which is implicitly defined by a level set function. The points selected are intersection points of the boundary with the grid lines of an underlying Cartesian grid. By the method, the interpolation stencils can be easily chosen to be locally uniform along a coordinate axis in two space dimensions and locally uniform on a coordinate plane in three space dimensions, which allows efficient numerical differentiation and boundary reconstruction/representation. An additional equilibrating process of boundary data further guarantees stable numerical differentiation. Numerical results demonstrating the method with examples in both two and three space dimensions are presented.

Optimization Empty Run for Multiple Contour Mixed Path Processing Based on Greedy and Genetic Algorithm

Aiming at the randomness of pel storage in the interactive graphics file used in the numerical control(NC) automatic programming, a new optimization method of contour machining path based on the greedy algorithm and genetic algorithm is proposed. The genetic algorithm is used to optimize the scheduling and processing sequence for each contour trajectory, and the greedy algorithm is also fused to select the control point of the empty run path between the two interfacing trajectories in the confirmed sequence. Then the total distance of empty run paths and the individual fitness are calculated according to the selected control points. The genetic manipulation is made to evaluate individual, which consists of selection, crossover and mutation. The method not only simplifies the coding, but also eliminates the invalid solution. The results of simulation and test prove that the method shortens the empty run distances, decreases the number of cutter landing gear, and improves the NC machining efficiency.

Calculation methodology of marine environmental capacity for heavy metal: A case study in Jiaozhou Bay, China

Results from past pollution control practices show that environmental quality can be ensured by controlling the actual amount of pollutants formed in the environment. Therefore, the marine environmental capacity for heavy metals was introduced. Marine environmental capacity for heavy metals is defined as the maximum amount of heavy metals permitted in the marine environment system to preserve the benign cycle of materials in the oceansphere, and to limit the adverse effects of heavy metals on the biosphere, hydrosphere, atmosphere, and lithosphere. Based on the box or three-dimensional model in the target coastal region, including the self-purification and output of heavy metals, the marine environmental capacity for heavy metals can be calculated within a given criterion and time. In this study, a method was proposed to calculate the marine environmental capacity for heavy metals which includes four steps: (1) gathering the basis information of target coastal ecosystem, (2) selection of water control points and water quality criteria for these points, (3) development of numerical models for the biogeochemical cycling of heavy metals in target coastal region, and (4) calculation of environmental capacity using the developed model. According to the proposed method, the marine environmental capacity for lead is approximately 60 tons per year if Grade I seawater quality is set as the control criterion in Jiaozhou Bay. An effective seawater quality management plan can also be framed based on the environmental capacity for metals.

Effect of different starter cultures on the biogenic amines production as a critical control point in fresh fermented sausages

The selection of critical control points is one of the most important steps in the design of a hazard analysis and critical control points system. In this study, the influence of starter culture inoculation on biogenic amine accumulation in fresh fermented sausage as critical control point was studied. The effect of three starter culture Lactobacillus plantarum plus Bifidobacterium lactis, L. plantarum plus Bifidobacterium bifidum or L. plantarum plus B. lactis and B. bifidum on amines production were investigated. Tyramine (TY), Cadaverine (CA), Putrescine (PU), Histamine (HIS) and Tryptamine (TR) contents increased during the fermentation and storage stage, and TY was the prevailing amine in the final product. Sausages produced by fermentation with starters, as compared to natural fermentation (control), had a lower amount of biogenic amine. A great reduction in biogenic amine content was achieved when Bifidobacterium sp. were inoculated, also levels of species of Enterobacteriaceae and Pseudomonas decreased, while lactic acid bacteria counts increased during fermentation and storage.