Coordinate Reference Research Articles

GEOREFERENCING IN IFC: MEETING THE REQUIREMENTS OF INFRASTRUCTURE AND BUILDING INDUSTRIES

Abstract. The problem of georeferencing building information modelling (BIM) models is complex and in need of a comprehensive solution. We focus on the open BIM data format Industry Foundation Classes (IFC) and its georeferencing implementation. The requirements voiced by the domain experts during recent years have been collected and analysed. While IFC already covers some of the concepts, we propose an extension to the IFC schema to handle the inadequacy. Our proposal composes of two new entities: one supports geographic coordinate reference systems (CRSs) and the other enables a rigid transformation of BIM geometries. We showcase the possibilities with three examples, one for each of the required scenarios. The improvements assure much-needed semantically clear definitions of the georeferencing concept within the IFC data model. As such, the interpretation of IFC data content is unambiguous for stakeholders and software implementers.

Visual-Based Spatial Coordinate Dominates Probabilistic Multisensory Inference in Macaque MST-d Disparity Encoding.

Numerous studies have demonstrated that animal brains accurately infer whether multisensory stimuli are from a common source or separate sources. Previous work proposed that the multisensory neurons in the dorsal medial superior temporal area (MST-d) serve as integration or separation encoders determined by the tuning–response ratio. However, it remains unclear whether MST-d neurons mainly take a sense input as a spatial coordinate reference for carrying out multisensory integration or separation. Our experimental analysis shows that the preferred tuning response to visual input is generally larger than vestibular according to the Macaque MST-d neuronal recordings. This may be crucial to serving as the base of coordinate reference when the subject perceives moving direction information from two senses. By constructing a flexible Monte-Carlo probabilistic sampling (fMCS) model, we validate this hypothesis that the visual and vestibular cues are more likely to be integrated into a visual-based coordinate rather than vestibular. Furthermore, the property of the tuning gradient also affects decision-making regarding whether the cues should be integrated or not. To a dominant modality, an effective decision is produced by a steep response-tuning gradient of the corresponding neurons, while to a subordinate modality a steep tuning gradient produces a rigid decision with a significant bias to either integration or separation. This work proposes that the tuning response amplitude and tuning gradient jointly modulate which modality serves as the base coordinate for the reference frame and the direction change with which modality is decoded effectively.

A Technique to Navigate Autonomous Underwater Vehicles Using a Virtual Coordinate Reference Network during Inspection of Industrial Subsea Structures

Industrial subsea infrastructure inspections using autonomous underwater vehicles (AUV) require high accuracy of AUV navigation relative to the objects being examined. In addition to traditional navigation tools with inertial navigation systems and acoustic navigation equipment, technologies with video information processing are also actively developed today. The visual odometry-based techniques can provide higher navigation accuracy for local maneuvering at short distances to objects. However, in the case of long-distance AUV movements, such techniques typically accumulate errors when calculating the AUV movement trajectory. In this regard, the present article considers a navigation technique that allows for increasing the accuracy of AUV movements in the coordinate space of the object inspected by using a virtual coordinate reference network. Another aspect of the method proposed is to minimize computational costs for AUV moving along the inspection trajectory by referencing the AUV coordinates to the object pre-calculated using the object recognition algorithm. Thus, the use of a network of virtual points for referencing the AUV to subsea objects is aimed to maintain the required accuracy of AUV coordination during a long-distance movement along the inspection trajectory, while minimizing computational costs.

An Acoustic 3-D Positioning System for Robots Operating Underground

Underground robots are potentially helpful in many application domains, including geotechnical engineering, agriculture, and archaeology. One of the critical challenges in developing underground robotics is the accurate estimation of the positions of the robots. Acoustic-based positioning systems have been explored for developing an underground 3-D positioning system. However, the positioning range is limited due to attenuation in the medium. This letter proposes an underground positioning system that utilizes a novel and easy-to-implement electronic approach for measuring the acoustic propagation times between multiple transmitters and a receiver. We demonstrate a prototype using four transmitters at the surface and a single buried acoustic sensor as a proof of concept. The times of arrival for signals emitted by the different sources are measured by correlating the transmitted and received signals. The distances between the multiple transmitters and a receiver are estimated, and a trilinearization algorithm is used to estimate the position of the buried sensor in 3-D with respect to reference coordinates. The system is tested in a soil tank. The experimental results show that the proposed system is able to estimate the 3-D position of buried sensors with an error of less than <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula> 2.5 cm within a measurement field of size 50 × 50 × 35 cm in <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</i> , <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Y</i> , and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z</i> (width × length × depth). The proposed electronic synchronization approach allows increasing the positioning range of the system by increasing the number of transmitters at the surface. This paves the way for the development of a positioning system for robots operating underground.

An approach for cross-data querying and spatial reasoning of tunnel alignments

In mechanized tunneling projects, finding a low-risk and cost-effective alignment is an important task. Several alignment variants are usually created and each one is intensely scrutinized. Variants often have individual advantages and disadvantages and can lead to different constructive designs of a tunnel. In order to find the best alignment possible the variants have to be analyzed and evaluated based on requirements and evaluation criteria, such as safety, cost, built environment and operational requirements. To perform this evaluation and to enable comprehensive decision making, a holistic planning environment is examined that includes documents and models of different domains. In general, these domain specific data differ schematically and semantically, which consequently makes it challenging to combine and compare such diverse data. For this purpose, information from different sources must be linked and evaluated in a structured way. In particular, spatial relationships have to be investigated. Therefore, in this paper, ontology databases are utilized to merge BIM and GIS at data level to create an integrated model of the entire tunneling project. Relevant information for decision-making can then be derived, such as the location of private and public buildings that are in a certain vicinity of the planned alignment. On the one hand, the implementation of queries is a popular and frequently used approach to check for semantic properties. On the other hand, using a query language to derive information from geometric data can be challenging, due to the necessity of processing geometric data prior to and during query execution. Additionally, geometric definitions can differ in the considered coordinate reference system, the dimension or the structure. To handle geometry information by employing query languages, representations are methodically transformed to well-known text literals. A simplified and uniform geometric representation can be utilized for spatial reasoning, for example by adopting GeoSPARQL methods.

Sagittal femoral condylar shape varies along a continuum from spherical to ovoid: a systematic review and meta-analysis.

Considerable anatomic variations of sagittal femoral condylar shape have been reported, with a continuum between spherical (or single-radius) and ovoid (or multi-radius) condyles. The purpose of this systematic review and meta-analysis was to critically appraise and synthesise the available literature on the sagittal femoral profile. The hypothesis was that studies would reveal considerable variability among individuals, but also in their methodology to quantify sagittal profiles. This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. On 10 September 2021 two authors searched for Level I to IV studies that reported on the sagittal curvature of the medial and/or lateral femoral condyles using the MEDLINE®, EMBASE® and Cochrane Library. Results were summarised by tabulating means, standard deviations and/or ranges for the reported radii-of-curvature, or ellipsoidal semi-major and semi-minor lengths of the condyles. To quantify sagittal 'ovoidicity' and asymmetry, results were stratified according to coordinate reference frame (posterior condylar axis (PCA), clinical and surgical transepicondylar axis (cTEA and sTEA), unified sagittal plane (USP), or unclear) and summarised in forest plots as standardised mean differences (SMD). Thirty-eight articles wereeligible for full text extraction, quantifyingsagittal radii-of-curvature by best-fit circles (BFC), ellipsoids, polynomials, spherical or cylindrical fitting. Studies with clear definition of the measurement plane revealed that both condyles were generally ovoid, with considerably greater 'ovoidicity' at the medial condyle (SMD, 4.09) versus the lateral condyle (SMD, 3.33). In addition, distal condylar radii were greater medially when measured normal to the TEA (cTEA: SMD, 0.81; sTEA: SMD, 0.79), but greater laterally when measured in a USP (SMD, -0.83). Posterior condylar radii were greater laterally when measured in a USP (SMD, -0.60). Studies reported considerable variability of sagittal femoral condylar radii-of-curvature, which arenot incremental, but rathera continuum that ranges from spherical to ovoid. Although this variation could be accommodated by single-, dual- and multi-radii femoral components, a surgeon typically uses only one or two TKA designs. Hence, there is a risk of mismatch between the native and prosthetic sagittal profile that could result in mid-flexion ligament imbalance unless other parameters are changed. These findings support the drive towards patient-specific implants to potentially achieve accurate sagittal bone-implant fit through implant customisation. IV.

The Oblique Mercator for engineering and survey

The Oblique Mercator (OM) has been the runt in the family of conformal coordinate projection where its particular attribute of arbitrary orientation has been largely ignored. It is proposed that the Oblique Mercator, as a conformal projection, is well-suited to bridge the gap between a conventional north-oriented projection and the family of engineering grids that are unit-scaled and arbitrarily oriented improve the management of coordinate reference systems (CRS) between GIS and CAD/BIM software that has been, and remains, a significant cause of inefficiency for engineering design and construction, and for plane surveying. Issues relating to the selection of an optimal set of HOM projection parameters are discussed, including a new method to transform an existing engineering grid into an optimised HOM grid.

GSPy: A new toolbox and data standard for Geophysical Datasets

The diversity of geophysical methods and datatypes, as well as the isolated nature of various specialties (e.g., electromagnetic, seismic, potential fields) leads to a profusion of separate data file formats and documentation conventions. This can hinder cooperation and reduce the impact of datasets researchers have invested in heavily to collect and prepare. An open, portable, and well-supported community data standard could greatly improve the interoperability, transferability, and long-term archival of geophysical data. Airborne geophysical methods particularly need an open and accessible data standard, and they exemplify the complexity that is common in geophysical datasets where critical auxiliary information on the survey and system parameters are required to fully utilize and understand the data. Here, we propose a new Geophysical Standard, termed the GS convention, that leverages the well-established and widely used NetCDF file format and builds on the Climate and Forecasts (CF) metadata convention. We also present an accompanying open-source Python package, GSPy, to provide methods and workflows for building the GS-standardized NetCDF files, importing and exporting between common data formats, preparing input files for geophysical inversion software, and visualizing data and inverted models. By using the NetCDF format, handled through the Xarray Python package, and following the CF conventions, we standardize how metadata is recorded and directly stored with the data, from general survey and system information down to specific variable attributes. Utilizing the hierarchical nature of NetCDF, GS-formatted files are organized with a root Survey group that contains global metadata about the geophysical survey. Data are then organized into subgroups beneath Survey and are categorized as Tabular or Raster depending on the geometry and point of origin for the data. Lastly, the standard ensures consistency in constructing and tracking coordinate reference systems, which is vital for accurate portability and analysis. Development and adoption of a NetCDF-based data standard for geophysical surveys can greatly improve how these complex datasets are shared and utilized, making the data more accessible to a broader science community. The architecture of GSPy can be easily transferred to additional geophysical datatypes and methods in future releases.

Improved RANSAC Point Cloud Spherical Target Detection and Parameter Estimation Method Based on Principal Curvature Constraint.

Spherical targets are widely used in coordinate unification of large-scale combined measurements. Through its central coordinates, scanned point cloud data from different locations can be converted into a unified coordinate reference system. However, point cloud sphere detection has the disadvantages of errors and slow detection time. For this reason, a novel method of spherical object detection and parameter estimation based on an improved random sample consensus (RANSAC) algorithm is proposed. The method is based on the RANSAC algorithm. Firstly, the principal curvature of point cloud data is calculated. Combined with the k-d nearest neighbor search algorithm, the principal curvature constraint of random sampling points is implemented to improve the quality of sample points selected by RANSAC and increase the detection speed. Secondly, the RANSAC method is combined with the total least squares method. The total least squares method is used to estimate the inner point set of spherical objects obtained by the RANSAC algorithm. The experimental results demonstrate that the method outperforms the conventional RANSAC algorithm in terms of accuracy and detection speed in estimating sphere parameters.

Mapping of DTPA Extractable Micronutrients in Sugarcane Soils of Sudhalagunta Sugar Factory, Andhra Pradesh, India – A GIS Approach

Sugarcane is the most important commercial crop grown in India and plays vital role in agricultural and industrial economy. In Andhra Pradesh, more than 50% of sugarcane is produced from Chittoor district for sugar and jaggery production. Sugarcane is heavy nutrient requirement crop and also removes considerable amount of nutrients through biomass. Continuous application of straight fertilizers, limited use of organic manures as well as non recycling of crop residues causes micronutrient deficiencies in soil. Keeping this in view, the present study was taken up to study the physico-chemical properties and DTPA extractable micronutrients and mapping of these nutrients. Soil samples along with geo reference coordinates were collected and analyzed for physico-chemical properties and DTPA extractable micronutrients (Fe, Mn, Zn and Cu). The digital soil maps for DTPA extractable micronutrients were generated with geo reference coordinates by using GIS approach. The analytical data of soils in Sudhalagunta sugar factory zone, Chittoor district showed that 80% of samples were slightly alkaline in reaction followed by 13% of samples were neutral in reaction. Regarding electrical conductivity, 16% of soils were slightly saline in nature. Among micronutrients, except DTPA-Zn, all cationic micronutrients were existed in above critical limit in this factory zone, 11% of soils showed Zn deficiency. Similar trend was noticed in plant Zn content. 18.4% of plant samples showed Zn deficiency. Remaining micronutrients were in sufficient range. Digital maps for DTPA - Fe, Mn, Zn and Cu have prepared.

Abstract 6400: JBrowse 2: An extensible open-source platform for modern genome analysis

Abstract Introduction: Genome browsers are useful tools for research in human genetics, able to display and integrate biological information such as long and short read sequencing data, variant calls, and annotations. While traditional linear genome browsers have demonstrated broad utility for many applications, there is an increasing need for visualizing complex structural variants (SVs) beyond the linear view. To meet these challenges, we created JBrowse 2: an extensible open-source platform for visualizing and integrating genomic data. Results: JBrowse 2 is a flexible platform that provides the foundation for the development of applications and web dashboards that combine novel views and representations extending beyond linear displays in genomic reference coordinates. For example, a flagship JBrowse 2 application is the SV Inspector, which lets users open a list of structural variants in a data table and see the results in a whole-genome circular view. Clicking on a given variant in the table or circular view opens up a linear view that displays the read evidence supporting the SV, even across complex breakpoints like translocations. Dotplot and synteny views are built-in, enabling “long read vs reference” dotplot visualizations, or alignments of de-novo assembled contigs to the genome. These views are integrated with each other, so that (for example) a long read is just a few clicks away from the corresponding dotplot. In addition to including these new views, the JBrowse 2 platform is designed from the ground up to enable third-party plugins to add new views, data adapters, and track types, which has facilitated the creation of new plugins that address some very specific use cases. These include our MSA view plugin for viewing multiple sequence alignments, data adapters that download data from UCSC and CIVIC APIs, and the Quantseq plugin for viewing quantitative motif scores as a genome browser track. JBrowse 2 is available as both a web app or a local desktop app. We also offer re-usable components on NPM, and users of R can programmatically create an instance of JBrowse 2 with the JBrowseR package on CRAN. JBrowse 2 can also generate high quality SVG snapshots from inside the app, and we also created a CLI tool called jb2export to perform automated or bulk exports of JBrowse 2 visualizations. We anticipate that JBrowse 2 will better serve genome scientists with its structural variant visualization capabilities, and will provide the flexibility to adapt to new visualization and analysis challenges as they emerge in the coming years. Citation Format: Scott Cain, Robin Haw, Caroline Bridge, Junjun Zhang, Robert Buels, Colin Diesh, Garrett Stevens, Teresa Martinez, Peter K. Xie, Elliot Hershberg, Shihab Dider, Lincoln Stein, Ian Holmes. JBrowse 2: An extensible open-source platform for modern genome analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6400.

Uncertain frequency response analysis of clamp-pipe systems via the coordinate transformed polynomial chaos expansion

The frequency response function (FRF) that links structural responses and external excitations is required to realize the dynamic analysis of a clamp-pipe system. Due to random geometry and stiffness parameters, the FRF becomes a stochastic quantity that is represented by a surrogate model based on the polynomial chaos expansion (PCE) in this paper. Considering that an FRF trajectory is mainly controlled by resonance and anti-resonance frequencies, a reference frequency coordinate characterized by the controlling frequencies associated with a nominal value of input random variables is first determined. By reserving the original amplitude, an FRF sample is projected to the reference coordinate through a linear transform. Then, a PCE surrogate model with coefficients estimated by the Gauss-quadrature scheme is obtained, and the utility of an inverse transform allows one to obtain the predicted FRF result in the original domain. Together with estimations on the confidence intervals and extreme boundary results, engineering applications are demonstrated by the uncertain FRF analysis of straight and L-shape clamp-pipe systems.

Rotation-Induced Geometrical Stiffening of a Tapered, Pretwisted Blade

A linear geometrical stiffening model is developed for a rotating beam with an asymmetric cross section undergoing coupled stretch–bending–torsion motion. The model is verified for a twisted and tapered Timoshenko beam mounted on a rotating hub with a presetting angle. The floating frame of reference formulation is adopted where the configuration of the deformable beam is described by using different coordinate systems. Three coordinate systems, viz., inertial reference frame attached to the center of the rigid hub, local reference frame attached to an arbitrary point on the elastic axis of the undeformed beam, and body reference frame attached to the point on the elastic axis of the deformed beam, are defined. The global position vector of an arbitrary point on the beam is specified using a coupled set of reference and elastic coordinates. Reference coordinates define the location and orientation of a body reference frame, and elastic coordinates describe the beam deformation about the body reference frame. For a rotating beam problem, reference and elastic coordinates give the angular displacements of the hub and elastic deformations of the beam, respectively. The expressions for the kinetic and strain energy of the deformable beam are derived. The inertial coupling between the reference and elastic coordinates in the kinetic energy expression is identified as a gyroscopic coupling term. Further, the inertial mass matrix, spin softening matrix, and centrifugal stiffening matrix are obtained from kinetic energy expression. The elastic stiffness matrices, which are independent of elastic coordinates, are derived from strain energy expression. According to the Rayleigh–Ritz method, the elastic coordinates are expressed using a series of admissible functions that satisfy the geometric boundary conditions of a fixed-free beam. The ordinary differential equations of motion are then derived using Lagrange’s equations. A set of dimensionless parameters is identified after the nondimensionalization of the equations of motion. Due to the skew-symmetric nature of the gyroscopic coupling matrix, the eigenvalue problem is not amenable to classical modal analysis. Therefore, a complex modal analysis method is used to determine the modal characteristics. The results from the present model are verified with those available in the literature. The results are also compared with those obtained from the three-dimensional finite element method using ANSYS. The effect of these dimensionless parameters on the modal characteristics of a rotating blade is studied.

ADAPTATION OF TEMPERATURE WALL FUNCTION FOR CALCULATION THE HEAT TRANSFER AT SUPERCRITICAL COOLANT PARAMETERS

To date, the engineering community pays special attention to the study, research and development of methods for predicting the behavior of the coolants at supercritical parameters. This paper discusses the problem of adaptation of the existing universal or specialized tools of thermohydraulic analysis for nonlinear heat transfer problems at supercritical coolant parameters with deterioration of heat transfer. Complexities of prediction the nonlinear heat transfer at supercritical parameters of the coolant by engineering methods of computational fluid dynamics are considered. A simple way to adapt the dual-zone Kader's temperature wall function on the basis of existing probe measurements for carbon dioxide is proposed. The problem of implementation into universal packages of computational fluid dynamics (CFD), which is based on the method of choosing the reference coordinate of the near-wall zone to determine the dynamic speed and dimensionless temperature, is discussed. The example on the ANSYS CFX using shows one of the ways to create a special user procedure, which has an improved tendency to predict the axial temperature profile with deteriorated heat transfer. Calibration and validation of the obtained results on the basis of experimental investigations for vertical pipes and rod assemblies of fuel simulators is carried out in the work. The paper also discusses the features of the proposed implementation, and formed recommendations for the application and further improvement of engineering approaches to predict the heat transfer deterioration at supercritical parameters of the coolant.

The explanation of two semi-recursive multibody methods for educational purpose

In this paper, two often-employed alternatives to the semi-recursive method are described and compared in terms of velocity transformation. The text offers a simplified way to understand the theory behind the two semi-recursive approaches. Focusing on planar cases, particular attention is given to reference and joint coordinates. Consequently, a multibody modeling analyst that is familiar with global formulations can easily extend his/her knowledge to the semi-recursive approach.Using semi-recursive methods, the open loops are formulated with a reduced set of coordinates, and the constraint equations are avoided in the dynamic equations of motion. Accordingly, computationally efficient forms of matrices and vectors will be generated to represent the dynamic equations of motion, which leads to enhanced numerical efficiency. The difference between the two studied alternatives is the definition of the reference point (i.e., the origin of the body frame) used to define the reference coordinates of the body. The reference point could be either (1) rigidly attached to the moving body for semi-recursive I or (2) coincident with the origin of the global frame for semi-recursive II. The latter leads to simple expressions of velocity transformation.

Development of a Methodology for Geoinformation Support for Geological Research of Ordovician Rocks of Gorny Altai

The relevance of the topic is determined by the fact that many rocks of the Ordovician age have been found in the Altai Mountains, which may be of interest to scientists studying the geology and paleontology of this period. The problem is connected that at the moment there are no maps with outcrops of Ordovician rocks in the public domain, there are only diagrams and schematic maps without a coordinate reference. The aim of the work is to develop a methodology for geoinformation support for geological research of Gorny Altai. To achieve this goal, it is necessary to solve the following tasks: geological survey and mapping of the territory of Gorny Altai; study of geological sections of the Ordovician age with consideration of their lithological specificity and taxonomic composition of faunal groups; prepare a multiscale cartographic framework. In the future, it is planned to create a geoportal that will display outcrops of Ordovician rocks and contain information on lithology and taxonomic composition.

On Finding a Projected Coordinate Reference System

The digital age has brought about an explosion in the growth of data, of which data with a geographical component stands out. Proper use of geographical data comes with the need for correct coordinate reference systems (CRSs). They are considered the ultimate binder for interoperability between geospatial data actors and stakeholders. Moreover, CRSs are crucial for the visual and analytical integration of geospatial data from disparate data sources. However, CRSs might be—for numerous reasons—incorrectly assigned or even missing. The result is a time-consuming study of the map, literature, and available resources to ultimately find the alleged right CRS. This study provides a summary of prevailing resources from national mapping agencies of some European countries to address the above problem. Secondly, and most importantly, is the development of an open-source Python-based software package. This software package aims to accurately estimate the best candidate CRS, given a tuple of coordinates at a priori an approximately known location. It is controlled by geocoding the known location and intersecting the resulting coordinate with the bounding box of all CRSs in the EPSG-database. An in-depth review of CRS tools by mapping authorities reveals, in particular, limitations concerning the countries’ spatial areas, in combination with often required know-how of local CRSs. To address these shortcomings, our tool is developed to enable a more generic extraction of CRSs for any given location worldwide. Testing proved successful for 30 different maps, with a grid present on the map and the CRS of the map being included in the EPSG-database.

Localization of Unidentified Events with Raw Microblogging Data

Event localization is the task of finding the location of an event. Commonly, event localization using microblogging services, like Twitter, use con- tents of the messages and the geographical information associated with the messages. In this paper, we propose a novel approach called SPARE (SPAtial REconstruction) that bypasses the need for geographical or semantic information to localize tweets. We assume there are reference coordinates at known locations that scrape the microblog (tweet) counts in time and space (circular regions around the reference coordinate). The counts of tweets are aggregated which are then disaggregated to identify event patterns. The change in counts of tweets would be indicative of an event pattern. We show, using real data, that the change in counts of tweets is manifested as peaks. The peaks from multiple reference coordinates can be used as an input to trilateration techniques to pinpoint the location of an event. We introduce metrics to identify the quality of disaggregation of fine-grained data and examine techniques like filtering to improve accuracy of event location. The experimental results show that our method can identify the location of an event with high accuracy.

The system of acquisition of information on indoor radon concentration with the motivated participation of the population

A system of acquisition of information on indoor radon concentration was developed. The system is based on the transfer of devices for integral and/or quasi-integral measurements of radon concentration to the owner of the premises and the exchange of necessary information about the conditions and measurement results between the owner and the measuring laboratory using modern online technology. The information support system implemented on the website and the use of mobile communication technologies are designed to attract additional measurement participants and expand the range of objects available for surveys. At the same time, intermediaries between the measuring laboratory and the owner of the premises are excluded. The use of cloud technologies makes it possible to optimize the exchange of information between participants, and the use of QR codes on detectors eliminates errors associated with the identification of the detector and its coordinate reference to the measurement point. The software modules used in the system automate the process of entering this information. It is assumed that devices with a track detector will be used as the main ones. It is also possible to use carbon-adsorption samplers, but only for measurements in settlements, from which delivery to the processing laboratory is possible within no more than one day. Testing of the possibility of practical use of the system by persons who are not specialists in the field of radiation control was carried out on examples of a small and large settlement (the village of Kochubeyevskaya and the city of Pyatigorsk, Stavropol Krai). In general, the testing showed the operability of the system. As a result, changes were made to the system: the size of QR codes was increased and their color palette was changed, and the supporting system was supplemented with information on entering the editing mode without a QR code. From a social point of view, the system provides economically affordable services for most citizens to determine the level of radon exposure in the air of residential, public and other buildings. At the same time, in the future, significant savings are achieved in budget allocations required to create a potential radon risk map of the country.

Robust Localization of Occluded Targets in Aerial Manipulation Via Range-Only Mapping

This letter studies the problem of target localization in aerial manipulation tasks. When an aerial robot flies close to a target to manipulate, the target would be occluded by the onboard robotic manipulator occasionally or for a long period of time. It is, however, necessary to continuously localize the target even when it is occluded. This is a unique problem in aerial manipulation and has not been addressed in other tasks such as ground manipulation. To solve this problem, we propose a new approach of target-centered range-only mapping based on RGB-D measurements. Different from the traditional map representation where the 3D locations of the feature points are stored in a global reference coordinate frame, we store the distances from the target to the environmental feature points only. It thus results in a coordinate-free target-centered range-only map. When the target is occluded, it can still be localized accurately based on the map. The proposed approach is verified by both synthetic and real datasets. The experimental results demonstrate the superior performance of our proposed approach to the state-of-the-art RGB-D ORB-SLAM3 method.