Global Reference System Research Articles

SECEC Grammont Award 2024: The critical role of posture adjustment for range of motion simulation in reverse total shoulder arthroplasty preoperative planning.

The objective of this study was to compare simulated range of motion (ROM) for reverse total shoulder arthroplasty (rTSA) with and without adjustment for scapulothoracic orientation in a global reference system. We hypothesized that values for simulated ROM in preoperative planning software with and without adjustment for scapulothoracic orientation would be significantly different. A statistical shape model of the entire humerus and scapula was fitted into ten shoulder CT scans randomly selected from 162 patients who underwent rTSA. Six shoulder surgeons independently planned a rTSA in each model using prototype development software with the ability to adjust for scapulothoracic orientation, the starting position of the humerus, as well as kinematic planes in a global reference system simulating previously described posture types A, B, and C. ROM with and without posture adjustment was calculated and compared in all movement planes. All movement planes showed significant differences when comparing protocols with and without adjustment for posture. The largest mean difference was seen in external rotation, being 62° (SD 16°) without adjustment compared to 25° (SD 9°) with posture adjustment (p < 0.001), with the highest mean difference being 49° (SD 15°) in type C. Mean extension was 57° (SD 18°) without adjustment versus 24° (SD 11°) with adjustment (p < 0.001) and the highest mean difference of 47° (SD 18°) in type C. Mean abducted internal rotation was 69° (SD 11°) without adjustment versus 31° (SD 6°) with posture adjustment (p < 0.001), showing the highest mean difference of 51° (SD 11°) in type C. The present study demonstrates that accounting for scapulothoracic orientation has a significant impact on simulated ROM for rTSA in all motion planes, specifically rendering vastly lower values for external rotation, extension, and high internal rotation. The substantial differences observed in this study warrant a critical re-evaluation of all previously published studies that examined component choice and placement for optimized ROM in rTSA using conventional preoperative planning software.

Regional tidal modeling on the European coast using tide gauges and satellite altimetry

The study investigates sea-level measurements along the coastal area of Europe for the 60-year (1961–2020) time span. Linear and quadratic modeling of tide gauge measurements showed an almost positive rate of trend of sea-level rise (0.09 to 3.6 mm/yr) and low acceleration (−0.05 to 0.40 mm/yr2). A least-squares harmonic estimation tidal modeling was carried out to estimate frequency (cycles per day) for a certain period. The smaller and higher tidal frequencies of these stations indicate their stability in terms of their surface variation. We used the 1993–2020 satellite altimetry data from the nearest grid points of the tide gauge station. The correlation coefficient between observed and satellite altimetry (lowest 0.53 and highest 0.93) varies at each station. This happens because of many factors that can affect the large difference in the sea-level trend between the satellite-derived and tide gauge results. Finally, to implement a global reference system for physical heights, the offshore topographic slope direction and slope range with contour spacing from the sea to the associated coastline were analyzed using bathymetry data. The abrupt change in slope from the coastline toward the sea can be seen toward the east, west, and southeast on the European coast. This is also an important factor that affects the variation of sea level.

Importance of magnetic information for neuronal plasticity in desert ants

Many animal species rely on the Earth's magnetic field during navigation, but where in the brain magnetic information is processed is still unknown. To unravel this, we manipulated the natural magnetic field at the nest entrance of Cataglyphis desert ants and investigated how this affects relevant brain regions during early compass calibration. We found that manipulating the Earth's magnetic field has profound effects on neuronal plasticity in two sensory integration centers. Magnetic field manipulations interfere with a typical look-back behavior during learning walks of naive ants. Most importantly, structural analyses in the ants' neuronal compass (central complex) and memory centers (mushroom bodies) demonstrate that magnetic information affects neuronal plasticity during early visual learning. This suggests that magnetic information does not only serve as a compass cue for navigation but also as a global reference system crucial for spatial memory formation. We propose a neural circuit for integration of magnetic information into visual guidance networks in the ant brain. Taken together, our results provide an insight into the neural substrate for magnetic navigation in insects.

Satellite-based InSAR Geodesy and Collocation with GNSS

Satellite radar interferometry (InSAR) enables large-scale monitoring of displacement with precision akin to ground-based methods. Using measurements from Sentinel-1 satellites, persistent scatterer networks cover areas up to hundreds of kilometers in size. One of the current challenges for the InSAR community is to tie these networks into a current and country-specific global terrestrial reference system through collocation with other geodetic techniques, especially Global Navigation Satellite Systems (GNSS). In this work, an optimal procedure for assessing a suitable collocation properties for InSAR and GNSS techniques is discussed, along with the proposal for the methodology to determine the spatial relationship between the reference points of both techniques. The study analyzes three collocation stations in Slovakia using their radar backscattering characteristics. InSAR achieves an intrinsic accuracy of up to 1 mm but has uncertainties several orders of magnitude larger in 3D space. A collocation of InSAR measurements with GNSS can tie relative InSAR displacement estimates to an absolute reference frame.

Regulation of atmospheric optical quantum communication links

The Russian Federation in 2023 adopted the concept of regulation of the quantum communication industry until 2030. The authors of this article took part in its development. The document substantiates the need to improve the legislation in optical communication. The study reveals that there is no global reference system for legally regulating optical communication, which will pose challenges in effectively overseeing atmospheric optical quantum communication lines. The article presents priority measures aimed at regulating atmospheric optical quantum communication lines, which will expand the commercial potential of quantum communication. The authors propose measures to protect the rights of users of quantum communication services, as well as the rights of owners of atmospheric optical quantum communication lines. In order to facilitate the operation of atmospheric optical quantum communication lines, it is essential to adopt measures beforehand, as legal uncertainties pose limitations on infrastructure project development.

Flora of the Canary Islands – revised checklist to a classic arena of botany

The Canary Islands are a popular location for botanical collections that resulted in a series of seminal works, including the description and documentation of many endemic plant species (Fig. 1, 2, 3) in herbaria. Viera y Clavijo, Christ, Webb, Berthelot, Sventenius, Pitard, Kunkel, or Bramwell, to name but a few, majorly contributed to the knowledge about the flora of the Canary Islands. Alexander von Humboldt’s botanical description of Tenerife during his stay in 1799 also motivated Charles Darwin to explore the island. Unfortunately, Darwin was not allowed to set foot on land during his voyage with the Beagle due to quarantine restrictions. In recent years, a number of data bases containing detailed information about the plants of the Canary Islands emerged. This botanical legacy evokes the expectation that detailed information about the flora of the archipelago is available, with high agreement about taxa and status between different sources. To test this expectation, we elaborated an extensive floral checklist for the Canary Islands, documented which taxa are accepted in global taxonomic reference systems, and additionally checked their coverage in databases that are a common sources in biogeographical and ecological research.

Dynamic Queries through Augmented Reality for Intelligent Video Systems

Artificial vision system applications have generated significant interest as they allow information to be obtained through one or several of the cameras that can be found in daily life in many places, such as parks, avenues, squares, houses, etc. When the aim is to obtain information from large areas, it can become complicated if it is necessary to track an object of interest, such as people or vehicles, due to the vision space that a single camera can cover; this opens the way to distributed zone monitoring systems made up of a set of cameras that aim to cover a larger area. Distributed zone monitoring systems add great versatility, becoming more complex in terms of the complexity of information analysis, communication, interoperability, and heterogeneity in the interpretation of information. In the literature, the development of distributed schemes has focused on representing data communication and sharing challenges. Currently, there are no specific criteria for information exchange and analysis in a distributed system; hence, different models and architectures have been proposed. In this work, the authors present a framework to provide homogeneity in a distributed monitoring system. The information is obtained from different cameras, where a global reference system is defined for generated trajectories, which are mapped independently of the model used to obtain the dynamics of the movement of people within the vision area of a distributed system, thus allowing for its use in works where there is a large amount of information from heterogeneous sources. Furthermore, we propose a novel similarity metric that allows for information queries from heterogeneous sources. Finally, to evaluate the proposed performance, the authors developed several distributed query applications in an augmented reality system based on realistic environments and historical data retrieval using a client–server model.

A Review of Selected Applications of GNSS CORS and Related Experiences at the University of Palermo (Italy)

Services from the Continuously Operating Reference Stations (CORS) of the Global Navigation Satellite System (GNSS) provide data and insights to a range of research areas such as physical sciences, engineering, earth and planetary sciences, computer science, and environmental science. Even though these fields are varied, they are all linked through the GNSS operational application. GNSS CORS have historically been deployed for three-dimensional positioning but also for the establishment of local and global reference systems and the measurement of ionospheric and tropospheric errors. In addition to these studies, CORS is uncovering new, emerging scientific applications. These include real-time monitoring of land subsidence via network real-time kinematics (NRTK) or precise point positioning (PPP), structural health monitoring (SHM), earthquake and volcanology monitoring, GNSS reflectometry (GNSS-R) for mapping soil moisture content, precision farming with affordable receivers, and zenith total delay to aid hydrology and meteorology. The flexibility of CORS infrastructure and services has paved the way for new research areas. The aim of this study is to present a curated selection of scientific papers on prevalent topics such as network monitoring, reference frames, and structure monitoring (like dams), along with an evaluation of CORS performance. Concurrently, it reports on the scientific endeavours undertaken by the Geomatics Research Group at the University of Palermo in the realm of GNSS CORS over the past 15 years.

The transformation matrix in the 7DOFs beam formulation

A non-negligible percentage of steel products for civil and industrial constructions is realised with members characterised by a mono-symmetric cross-section. The non-coincidence between the centroid and the shear centre reflects in a quite complex behaviour that is remarkably influenced by the warping effects. Usually, frame design is based on the output data of commercial Finite Element Analysis Packages (FEAPs) but only few of them offer a refined beam element formulation able to reproduce the response of non-bisymmetric cross-section members (like the 7 degrees of freedom, DOFs, beam element). As a consequence, warping effects are usually neglected in routine design, leading in several cases to assess non-correct internal stresses, global displacements and critical buckling multipliers.This paper is focussed on mono-symmetric cross-section members and deals with the influence of the interaction between axial force, bending moments and bimoment in linear elastic range. In particular, the two strategies that FE developers usually adopt, in the 7 DOFs beam formulation, to pass from the local to the global reference system are herein shortly introduced and discussed. The effects of the associated transformation matrices have been investigated in few examples, also reproduced via closed expressions derived from the mixed torsion theory and FE shell models. Paper outcomes show that the results in terms of generalised displacements, internal forces and, consequently, stress distribution along the member cross-section are significantly different, strictly depending on the adopted transformation matrix. The importance of a correct evaluation of the bimoment distribution is stressed also by the fact that the new edition of the EN1993-1-1, expected in the next months, includes also the bimoment contribution for member checks.

Multi-Sensor Data Fusion for 3D Reconstruction of Complex Structures: A Case Study on a Real High Formwork Project

As the most comprehensive document types for the recording and display of real-world information regarding construction projects, 3D realistic models are capable of recording and displaying simultaneously textures and geometric shapes in the same 3D scene. However, at present, the documentation for much of construction infrastructure faces significant challenges. Based on TLS, GNSS/IMU, mature photogrammetry, a UAV platform, computer vision technologies, and AI algorithms, this study proposes a workflow for 3D modeling of complex structures with multiple-source data. A deep learning LoFTR network was used first for image matching, which can improve matching accuracy. Then, a NeuralRecon network was employed to generate a 3D point cloud with global consistency. GNSS information was used to reduce search space in image matching and produce an accurate transformation matrix between the image scene and the global reference system. In addition, to enhance the effectiveness and efficiency of the co-registration of the two-source point clouds, an RPM-net was used. The proposed workflow processed the 3D laser point cloud and UAV low-altitude multi-view image data to generate a complete, accurate, high-resolution, and detailed 3D model. Experimental validation on a real high formwork project was carried out, and the result indicates that the generated 3D model has satisfactory accuracy with a registration error value of 5 cm. Model comparison between the TLS, image-based, data fusion 1 (using the common method), and data fusion 2 (using the proposed method) models were conducted in terms of completeness, geometrical accuracy, texture appearance, and appeal to professionals. The results denote that the generated 3D model has similar accuracy to the TLS model yet also provides a complete model with a photorealistic appearance that most professionals chose as their favorite.

Global geopotential models evaluation based on terrestrial gravity data over Ethiopia

Abstract The availability of high-degree and recent global geopotential models is a crucial resource for different geodetic and geophysical applications such as modelling of geoid and quasi-geoid and establishing global reference and height systems, estimating Moho depth, gravity anomaly and tectonics, other geopotential functional, and oceanography, which emphasizes the importance for model evaluation. We have therefore estimated complete Bouguer anomalies and Moho whose results are evaluated with the terrestrial values. We validate the recently released satellite-only and high-degree combined GGMs over Ethiopia using terrestrial gravity data based on a statistical comparison of the Bouguer anomaly, its residual and Moho depth. The terrestrial-derived gravity anomaly is more accurately estimated by EIGEN6C4. The assessment against a recently conducted high resolution (∼3 km) terrestrial and airborne gravimetric survey over Ethiopia shows that EIGEN6C4/SGG_UGM_1 and 2 have the highest accuracy (∼3.28/3.27 mGal). However, the comparison with such data hardly discriminates the qualities of other GGMs that have or are truncated to the same degree and order. Whereas, the validation results of GGMs against terrestrial and airborne data are identical. EIGEN6C4, SGG_UGM_2, XGM2016, XGM2019e_2159/SGG_UGM_1 have the best quality, and the accuracy of associated Moho is 4.89/4.90 km, and this value changes to 4.98/4.91/5.51 km when the EGM08/ITSG_Grace2018s/GOCO06S are assessed.

Hybrid solar thermal and heat pump systems in industry: Model based development of globally applicable design guidelines

Solar thermal heating systems and heat pumps are key technologies for decarbonizing low temperature industrial heat demand. Fluctuating solar irradiance, limited heat source capacity or limited availability of renewable electricity often limit the potential of the single technologies. To maximize the share of renewable heat supply, the combination of both technologies is a promising option. This study takes the first steps towards filling the research gap of missing guidelines for preliminary design or feasibility studies. A simulation tool based on idealized component models is used to compare technical and economic performance for 30,240 parameter combinations, that define various global reference applications, system designs, and economic frameworks. The heat sink and source temperatures, and the energy prizes have the highest impact on the economic performance. The potential for technical optimization is small. If the fraction of both heat generators together is close to 100 %, SCOP differences between different hydraulic concepts are neglectable. The most viable option for optimizing the system's LCOH is to reduce the heat pump capacity to about the half of the annual peak load. Due to recent increases in energy prices, a complete decarbonization is economically feasible without subsidies for most of the applications studied.

Utilización de los valores absolutos de la aceleración de la gravedad para obtener el factor de escala de los gravímetros Lacoste&amp;Romberg Modelo G.

The Military Geographic Institute (IGM) is the institution responsible for maintaining and updating the official geodesic reference system of Chile put into effect through the National Geodesic Network (RGN), which consists of the Horizontal and Vertical RGNs. This latter element is made up of the leveling network, constituted by altitude points referenced to the Mean Sea Level (M.S.L.) and the Gravimetric Network, consisting of absolute and relative stations, with gravity acceleration values (g), referenced to the International Gravity Standardization Network 1971 (IGSN-71). The IGSN-71 was adopted as the world reference for gravimetric measurement at the 25th General Assembly of the International Union of Geodesy and Geophysics (IUGG) in 1971 with a precisión of ± 0,1 mGal. This current research work is mainly focused on making known the chief features of the operation and correct use of the instrument measuring the gravity acceleration (g) that the IGM uses for its gravimetric projects. The instrumental calibration procedure is made known here, obtaining the “scale” (adjustment) factor for each Lacoste&amp;Romberg model G gravimeter in orderto obtain more accurate gravity values.The above is sustained in relation to the requirements suggested by international organisations in the area of geodesy, such as the International Association of Geodesy (IAG) and SIRGAS, which encourage all nations to implement homogeneous and precise global vertical reference systems, in which gravimetry is an essential factor in setting up a new vertical reference frame for the whole country, adopting physical heights.

Uso de valores absolutos de aceleración de gravedad para el factor de escala de gravímetros Lacoste&amp;Romberg Modelo G.

The Military Geographic Institute (IGM) is the institution responsible for maintaining and updating the official geodesic reference system of Chile put into effect through the National Geodesic Network (RGN), which consists of the Horizontal and Vertical RGNs. This latter element is made up of the leveling network, constituted by altitude points referenced to the Mean Sea Level (M.S.L.) and the Gravimetric Network, consisting of absolute and relative stations, with gravity acceleration values (g), referenced to the International Gravity Standardization Network 1971 (IGSN-71). The IGSN-71 was adopted as the world reference for gravimetric measurement at the 25th General Assembly of the International Union of Geodesy and Geophysics (IUGG) in 1971 with a precisión of ± 0,1 mGal. This current research work is mainly focused on making known the chief features of the operation and correct use of the instrument measuring the gravity acceleration (g) that the IGM uses for its gravimetric projects. The instrumental calibration procedure is made known here, obtaining the “scale” (adjustment) factor for each Lacoste&amp;Romberg model G gravimeter in orderto obtain more accurate gravity values.The above is sustained in relation to the requirements suggested by international organisations in the area of geodesy, such as the International Association of Geodesy (IAG) and SIRGAS, which encourage all nations to implement homogeneous and precise global vertical reference systems, in which gravimetry is an essential factor in setting up a new vertical reference frame for the whole country, adopting physical heights.

Synergy of Geospatial Data from TLS and UAV for Heritage Building Information Modeling (HBIM)

Currently, Building Information Modeling (BIM) is increasingly entering the operational level in terms of creating a model for newly constructed facilities. For existing objects, and objects of Culture Heritage (CH), the creation of coherent and qualitative BIM models depends on the quality of the data constituting the basis for modelling. What’s more, BIM of CH is not only a challenge to obtain high-quality three-dimensional data, but also a time-consuming study of object documentation and photographic documentation in order to create a faithful library of parametric objects. In the article, the authors presented the synergy of spatial data with TLS and UAV as the basis for creating a BIM model for two CH objects. The aim of the article was to make such a synergy of TLS and UAV data that the geospatial database, developed for the needs of modelling historic objects in the HBIM trend, would have a specific amount of information without the frequently used redundancy. In principle, the acquired 3D database should be expressed in a global reference system with the degree of georeferencing accuracy for situational and altitude measurements and should be consistent to provide comprehensive information about the object. The analyses led to conclusions in which the authors assign superior importance to the accuracy of measurement information and the integration of individual data groups in the process of developing the HBIM model with the desired accuracy in opposition to the appropriate selection of the level of detail, which is usually assigned a superior role, which in turn results from the quality of the data geospatial modelling.

The application of an artificial neural network for 2D coordinate transformation

Abstract Clark1880, WGS1984, and ITRF08 are the reference systems used in Iraq. The ITRF08 and WGS84 represent the global reference frames. In the majority of instances, the transformation from one coordinate system to another is required. The ability of the artificial neural network (ANN) to identify the connection between two coordinate systems without the need for a mathematical model is one of its most significant benefits. In this study, an ANN was employed for two-dimensional coordinate transformation from local Clark1880 to the global reference system ITRF08. To accomplish so, 68 stations with known coordinates in both systems were utilized in this research and were split into two groups: the first set of data (38 stations) was used as the training data and the second set of data (38 stations) was used as the validation data. A root-mean-square error (RMSE) was used to examine the performance of each transformation. The results showed that the RMSE using the ANN was 0.08 m in the east and 0.17 m in the north. The results indicated that the ANN can be used for 2D coordinate transformation with the results that are better than those of the authorized techniques such as 2D conformal transformation and 2D conformal least square.

Data fusion of local and global sensors within a Global Reference System in aeroplane assembly

Abstract Currently, aeroplane assembly is carried out in rigid, aeroplane-specific assembly lines which causes high costs for reconfiguration. One approach to reduce the costs is to use automated lineless assembly systems. To enable automated reconfiguration of assembly processes, continuous availability of factory-wide position data is required. When providing these data, a challenge is the combination of large-volume, “global” measurement sensors and high-precision, “local” measurement sensors to a single easily interpretable indication. The aim of this research work is the fusion of local and global measurement data within a so-called Global Reference System (GRS). For data fusion, sensors are linked to a reference measurement system covering the entire assembly area. The relationships between the coordinate systems of the individual measurement systems are described using homogeneous transformations. Using Kalman filters, the transformed measurement data are fused into a vector containing information about the pose of aeroplane components. Furthermore, a GUM-compliant statement about the measurement uncertainty of the fused sensor data is made by specifying the covariance matrix. The method is validated using a demonstrator covering the essential aspects of the assembly process. The result is a validated procedure for data fusion and for the determination of the combined measurement uncertainty in a GRS.

Analysis of vertical reference levels in the brazilian coast: comparing local and global approaches

There is a historical search for the unification of different geodetic reference systems in order to better integrate geodetic investigations. In particular, coastal zones pose the challenge of connecting terrestrial and oceanic references when working with different vertical reference levels. This study aims to investigate the goodness-of-fit of ocean models to local observations, as well as to update and improve reference levels (RL) in two tide gauges (TGs) in Brazil (Imbituba and Fortaleza). Local RLs were connected to a global reference system (GRS80), which allowed absolute analyses using the mean sea surface (MSS) and lowest astronomical tide (LAT) models MSS_CNES_ CLS15, DTU_15_MSS, DTU_18_MSS and DTU_15_LAT. In the selected TGs, the MSS models showed a difference of centimeters in regards to the local mean sea level (MSL) defined by the Directorate of Hydrography and Navigation (DHN). Sea Surface Topography (SSTop) values were estimated from Global Geopotential Models and MSL data. The results indicated possible inconsistencies in the global model of LAT when compared to local observations, likely due to the difficulty of modeling coastal zones.

A Redundant Configuration of Four Low-Cost GNSS-RTK Receivers for Reliable Estimation of Vehicular Position and Posture.

This paper proposes a low-cost sensor system composed of four GNSS-RTK receivers to obtain accurate position and posture estimations for a vehicle in real-time. The four antennas of the receivers are placed so that every three-antennas combination is optimal to get the most precise 3D coordinates with respect to a global reference system. The redundancy provided by the fourth receiver allows to improve estimations even more and to maintain accuracy when one of the receivers fails. A mini computer with the Robotic Operating System is responsible for merging all the available measurements reliably. Successful experiments have been carried out with a ground rover on irregular terrain. Angular estimates similar to those of a high-performance IMU have been achieved in dynamic tests.

Autonomous Flight Trajectory Control System for Drones in Smart City Traffic Management

With the exponential growth of numerous drone operations ranging from infrastructure monitoring to even package delivery services, the integration of UAS in the smart city transportation systems is an actual task that requires radically new, sustainable (safe, secure, with minimum environmental impact and life cycle cost) solutions. The primary objective of this proposed option is the definition of routes as desired and commanded trajectories and their autonomous execution. The airspace structure and fixed routes are given in the global GPS reference system with supporting GIS mapping. The concept application requires a series of further studies and solutions as drone trajectory (or corridor) following by an autonomous trajectory tracking control system, coupled with autonomous conflict detection, resolution, safe drone following, and formation flight options. The second part of the paper introduces such possible models and shows some results of their verification tests. Drones will be connected with the agency, designed trajectories to support them with factual information on trajectories and corridors. While the agency will use trajectory elements to design fixed or desired trajectories, drones may use the conventional GPS, infrared, acoustic, and visual sensors for positioning and advanced navigation. The accuracy can be improved by unique markers integrated into the infrastructure.