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Journal articles on the topic 'Observation points grid'

Author: Grafiati

Published: 28 May 2022

Last updated: 31 July 2025

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1

Kim, Ki-Hwan, Eun-Hee Lee, and Song-You Hong. "Potential of Voronoi Diagram for the Conserved Remapping of Precipitation." Monthly Weather Review 146, no. 7 (2018): 2237–46. http://dx.doi.org/10.1175/mwr-d-17-0350.1.

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Abstract This study considers a remapping algorithm between irregularly distributed observations and grid points based on Voronoi diagrams and examines its potential for verification of precipitation forecasts. We propose a new remapping method using Voronoi diagrams to apply conservative area-weighted remapping on grid data to station points, describing a representative area for each station point. Conservative remapping is applied to interpolate daily precipitation data between grid and station points over South Korea. The proposed method shows significant differences from bilinear interpola

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Lapich, A. O., та M. Y. Medvedik. "Algorithm for Searching Inhomogeneities in Inverse Nonlinear Diﬀraction Problems". Uchenye Zapiski Kazanskogo Universiteta. Seriya Fiziko-Matematicheskie Nauki 166, № 3 (2024): 395–406. http://dx.doi.org/10.26907/2541-7746.2024.3.395-406.

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This study aims to solve the inverse problem for determining the heterogeneity of an object. The scattered ﬁeld was measured outside its boundaries at a set of observation points. Both the radiation source and observation points were assumed to be located outside the object. The scattered ﬁeld was modeled by solving the direct problem. The inverse problem was solved using a two-step method. Nonlinearities of various types were considered. When introducing the computational grid, the generalized grid method was applied. A numerical method for solving the problem was proposed and implemented. Th

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Klaas, Dua K. S. Y., Monzur Alam Imteaz, and Arul Arulrajah. "Evaluating the impact of grid cell properties in spatial discretization of groundwater model for a tropical karst catchment in Rote Island, Indonesia." Hydrology Research 48, no. 6 (2016): 1757–72. http://dx.doi.org/10.2166/nh.2016.250.

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Abstract To assess the effect of three grid cell properties (size, mean slope of the surface and distance between centre of grid and observation well) on groundwater models' performances, a tropical karst catchment characterized by monsoonal season in Rote Island, Indonesia was selected. Here, MODFLOW was used to develop models with five different spatial discretization schemes: 10 × 10 m, 20 × 20 m, 30 × 30 m, 40 × 40 m and 50 × 50 m. Using parameter estimation method, hydraulic conductivity and specific yield values over a selection of pilot points were estimated. The trends of the performan

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Hoffman, Ross N., Rui M. Ponte, Eric J. Kostelich, et al. "A Simulation Study Using a Local Ensemble Transform Kalman Filter for Data Assimilation in New York Harbor." Journal of Atmospheric and Oceanic Technology 25, no. 9 (2008): 1638–56. http://dx.doi.org/10.1175/2008jtecho565.1.

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Abstract Data assimilation approaches that use ensembles to approximate a Kalman filter have many potential advantages for oceanographic applications. To explore the extent to which this holds, the Estuarine and Coastal Ocean Model (ECOM) is coupled with a modern data assimilation method based on the local ensemble transform Kalman filter (LETKF), and a series of simulation experiments is conducted. In these experiments, a long ECOM “nature” run is taken to be the “truth.” Observations are generated at analysis times by perturbing the nature run at randomly chosen model grid points with errors

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Stepanova, Inna, Dmitry Lukyanenko, Igor Kolotov, Alexey Shchepetilov, and Anatoly Yagola. "On the Unique Solvability of Inverse Problems of Magnetometry and Gravimetry." Mathematics 11, no. 14 (2023): 3230. http://dx.doi.org/10.3390/math11143230.

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This article deals with the question of the unique solvability of systems of linear algebraic equations, to the solution of which many inverse problems of geophysics are reduced as a result of discretization when applying the methods of integral equations or integral representations. Examples are given of degenerate and nondegenerate systems of different dimensions that arise in the processing of magnetometric and gravimetric data from experimental observations. Conclusions are drawn about the methods for constructing the optimal grid of experimental observation points.

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Jahandari, Hormoz, and Colin G. Farquharson. "A finite-volume solution to the geophysical electromagnetic forward problem using unstructured grids." GEOPHYSICS 79, no. 6 (2014): E287—E302. http://dx.doi.org/10.1190/geo2013-0312.1.

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The application of unstructured grids can improve the solution of total field electromagnetic problems because these grids allow efficient local refinement of the mesh at the locations of high field gradients. Unstructured grids also provide the flexibility required for representing arbitrary topography and subsurface interfaces. We investigated the generalization of the standard Yee’s staggered scheme to unstructured tetrahedral-Voronoï grids using a finite-volume approach. We discretized the Helmholtz equation for the electric field in the frequency domain and solved the problem to find the

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Lin, Lijuan, Licheng Xing, Qingquan Jia, and Xuerui Zhang. "Research on the Partition Method Based on the Observation Points of Voltage Distortion in Harmonic Optimization." Journal of Physics: Conference Series 2253, no. 1 (2022): 012005. http://dx.doi.org/10.1088/1742-6596/2253/1/012005.

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Abstract With the use of a large number of power electronic equipment, the harmonics in the power grid are becoming more and more serious. There are many methods for harmonic mitigation and optimization such as Global network Optimization. When there are many nodes, the global network optimization method is more complicated. Considering the problem of large numbers of harmonic injection nodes in the power grid, this paper proposes a method of clustering the voltage distortion nodes according to correlation, and using the characteristic nodes to describe the harmonic voltage distortion in the r

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Tao, Jun, Gang Sun, Ying Hu, and Miao Zhang. "Noise Prediction for Multi-Element Airfoil Based on FW-H Equation." Applied Mechanics and Materials 52-54 (March 2011): 1388–93. http://dx.doi.org/10.4028/www.scientific.net/amm.52-54.1388.

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In this article, four observation points are selected in the flow field when predicting aerodynamic noise of a multi-element airfoil for both a coarser grid and a finer grid. Numerical simulation of N-S equations is employed to obtain near-field acoustic information, then far-field acoustic information is obtained through acoustic analogy theory combined with FW-H equation. Computation indicates: the codes calculate the flow field in good agreement with the experimental data; The finer the grid is, the more stable the calculated sound pressure level (SPL) is and the more regularly d(SPL)/d(St)

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Laakkonen, Mika-Petri, Ville Kivivirta, Antonio Calò, and Eva Pongrácz. "Smart Grid in the Arctic City." Journal of Northern Studies 16, no. 2 (2024): 55–81. http://dx.doi.org/10.36368/jns.v16i2.1125.

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This article presents the evolution of a smart grid in an artic city, and we analyze its development using the Smart Grid Reference Architecture (SGAM) and from historical, technological, and social points of view in an Arctic context. We illustrate the emergence of smart grid application and its relation to energy consumption habits and sustainability. The study includes observations from empirical research conducted using a mixed methods approach. This included two months of organizational ethnographies consisting of interviews with specialists at an electricity utility, shadowing the worker

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Rifani, Achmad, and Muhammad Rezza Ferdiansyah. "High-resolution-gridded rainfall dataset derived from surface observation by adjustment of satellite rainfall product." Proceedings of The International Conference on Data Science and Official Statistics 2023, no. 1 (2023): 516–23. http://dx.doi.org/10.34123/icdsos.v2023i1.314.

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A high-resolution-gridded rainfall dataset is essential for many purposes. Such as analysis of extreme weather conditions, natural-disaster mitigation, or to be used as an input to the hydrological model. Satellite-based rainfall products (e.g., Global Satellite Mapping of Precipitation-GSMaP) can solve the spatial and temporal issues despite their rainfall intensity often being under or overestimated. This research aims to provide a high-resolution rainfall dataset by adjusting the 0.1 deg GSMaP rainfall data to the surface rainfall data from several observation points in the greater Jakarta

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Horn, Berthold K. P. "Observation Model for Indoor Positioning." Sensors 20, no. 14 (2020): 4027. http://dx.doi.org/10.3390/s20144027.

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The IEEE 802.11mc WiFi standard provides a protocol for a cellphone to measure its distance from WiFi access points (APs). The position of the cellphone can then be estimated from the reported distances using known positions of the APs. There are several “multilateration” methods that work in relatively open environments. The problem is harder in a typical residence where signals pass through walls and floors. There, Bayesian cell update has shown particular promise. The Bayesian grid update method requires an “observation model” which gives the conditional probability of observing a reported

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Neyolov, V. V., and A. A. Samorodov. "Estimation of statistical radar characteristics of object by spatial diagram of backscattering in equidistant angular grid." Ural Radio Engineering Journal 6, no. 3 (2022): 259–68. http://dx.doi.org/10.15826/urej.2022.6.3.002.

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The methodological approach to estimation the statistical radar characteristics (mean, median and rms-square deviation values of RCS) of an object using a spatial diagram of backscattering formed in nodes of an equidistant azimuthal-angular coordinate grid is presented. The proposed approach is tried out using the model spatial diagram of backscattering of the tested object. The approach is based on the assumption of the uniform law of distributing he views of an object and implements the formation of a variation series from the samples of the RCS diagram weighted with the probability density

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Luka, Strezoski, Babic Zorana, and Milojicic Dejan. "Cyber Physical Security of Distributed Energy Resources." Energija, ekonomija, ekologija XXV, no. 4 (2023): 1–9. http://dx.doi.org/10.46793/eee23-4.01s.

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Huge amounts of data are coming from the electrical grid, through smart meters, smart inverters, and Supervisory Control and Data Acquisition (SCADA) protocols. This makes emerging power systems, and especially distribution grids, heavily dependent on real-time data from the field, as well as on the IT infrastructure for observation and control of field devices. As a consequence, emerging electrical systems are becoming fully digitized, cyber-physical systems with all the accompanying advantages and challenges. Such a power system is called a “Smart Grid”. As all cyber-physical systems, Smart

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Maley, S. M., and R. C. Mawhinney. "How the Amount of Hartree-Fock Exchange Affects the Observation of the Pseudo Jahn-Teller Effect." Journal of Physics: Conference Series 2769, no. 1 (2024): 012003. http://dx.doi.org/10.1088/1742-6596/2769/1/012003.

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Abstract Heavy group 14 analogs of planar carbon molecules are well known to prefer bent or pyramidalized geometries. The pseudo Jahn-Teller effect (pJTE) is a general approach to understanding the origin of such molecular geometries. Computationally intensive multi-reference post Hartree-Fock methods are generally required to obtain values relevant to the pJTE. However, an alternative approach, using more computationally efficient density functional theory (DFT) and fitting a model vibronic Hamiltonian, can account for the pJTE parameters. Previous studies have detailed the effect of both int

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Gościewski, Dariusz, Małgorzata Gerus-Gościewska, and Agnieszka Szczepańska. "Application of Polynomial Interpolation for Iterative Complementation of the Missing Nodes in a Regular Network of Squares Used for the Construction of a Digital Terrain Model." Remote Sensing 16, no. 6 (2024): 999. http://dx.doi.org/10.3390/rs16060999.

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Due to the continuous increase in the volume of spatially located information, the current requirements imposed on the Spatial Information System (SIS) concern increasing data mining capabilities. Modern measurement systems, based on devices which enable the automatic recording of observation results on a mass scale (LiDAR—Light Detection and Ranging, MBES—Multi Beam Echo Sounder, etc.), allow for a very large volume of information on the surface to be measured and acquired in a relatively short time. One of the methods to reduce the volume of data enabling the generation of a model surface is

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DeGaetano, Arthur T., and Brian N. Belcher. "Spatial Interpolation of Daily Maximum and Minimum Air Temperature Based on Meteorological Model Analyses and Independent Observations." Journal of Applied Meteorology and Climatology 46, no. 11 (2007): 1981–92. http://dx.doi.org/10.1175/2007jamc1536.1.

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Abstract Hourly meteorological forecast model initializations are used to guide the spatial interpolation of daily cooperative network station data in the northeastern United States. The hourly model data are transformed to daily maximum and minimum temperature values and interpolated to the station points after standardization to station elevation based on the model temperature lapse rate. The resulting bias (interpolation − observation) is computed and then interpolated back to the model grids, allowing daily adjustment of the temperature fields based on independent observations. These adjus

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Reen, Brian P., Robert E. Dumais, and Jeffrey E. Passner. "Mitigating Excessive Drying from the Use of Observations in Mesoscale Modeling." Journal of Applied Meteorology and Climatology 55, no. 2 (2016): 365–88. http://dx.doi.org/10.1175/jamc-d-14-0301.1.

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AbstractObservations can be used to enhance mesoscale model forecasts by both improving the initial conditions and adjusting the model state toward the observations during its forward integration. Since observations are not available at the same density as the model grid points, spatial and temporal error correlations must be specified in order to effectively assimilate the observations into the model. Overdrying is found while applying the Weather Research and Forecasting Model to five cases centered over Southern California. This overdrying is caused by incorporation of observations in the i

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Cordell, Lindrith. "A scattered equivalent‐source method for interpolation and gridding of potential‐field data in three dimensions." GEOPHYSICS 57, no. 4 (1992): 629–36. http://dx.doi.org/10.1190/1.1443275.

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Potential‐field geophysical data observed at scattered discrete points in three dimensions can be interpolated (gridded, for example, onto a level surface) by relating the point data to a continuous function of equivalent discrete point sources. The function used here is the inverse‐distance Newtonian potential. The sources, located beneath some of the data points at a depth proportional to distance to the nearest neighboring data point, are determined iteratively. Areas of no data are filled by minimum curvature. For two‐dimensional (2-D) data (all data points at the same elevation), grids ca

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Avsar, N. B., S. H. Kutoglu, S. Jin, and B. Erol. "INVESTIGATON OF SEA LEVEL CHANGE ALONG THE BLACK SEA COAST FROM TIDE GAUGE AND SATELLITE ALTIMETRY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-1-W5 (December 10, 2015): 67–71. http://dx.doi.org/10.5194/isprsarchives-xl-1-w5-67-2015.

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In this study, we focus on sea level changes along the Black Sea coast. For this purpose, at same observation period the linear trends and the components of seasonal variations of sea level change are estimated at 12 tide gauge sites (Amasra, Igneada, Trabzon-II, Sinop, Sile, Poti, Batumi, Sevastopol, Tuapse, Varna, Bourgas, and Constantza) located along the Black Sea coast and available altimetric grid points closest to the tide gauge locations. The consistency of the results derived from both observations are investigated and interpreted. Furthermore, in order to compare the trends at the sa

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Susemiehl, Nicholas, Avi M. Mandell, Geronimo L. Villanueva, et al. "Grid-based Atmospheric Retrievals for Reflected-light Spectra of Exoplanets Using PSGnest." Astronomical Journal 166, no. 3 (2023): 86. http://dx.doi.org/10.3847/1538-3881/ace43b.

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Abstract Techniques to retrieve the atmospheric properties of exoplanets via direct observation of their reflected light have often been limited in scope owing to computational constraints imposed by the forward-model calculations. We have developed a new set of techniques that significantly decrease the time required to perform a retrieval while maintaining accurate results. We constructed a grid of 1.4 million precomputed geometric albedo spectra valued at discrete sets of parameter points. Spectra from this grid are used to produce models for a fast and efficient nested sampling routine cal

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Zhu, Chengcheng, Jinyun Guo, Jiajia Yuan, Xin Jin, Jinyao Gao, and Chengming Li. "Refining Altimeter-Derived Gravity Anomaly Model from Shipborne Gravity by Multi-Layer Perceptron Neural Network: A Case in the South China Sea." Remote Sensing 13, no. 4 (2021): 607. http://dx.doi.org/10.3390/rs13040607.

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Shipborne gravity can be used to refine altimeter-derived gravity whose accuracy is low in shallow waters and areas with complex submarine topography. As altimeter-derived gravity only within a small radius around the shipborne data can be corrected by traditional methods, a new method based on multi-layer perceptron (MLP) neural network is proposed to refine the altimeter-derived gravity. Input variables of MLP include the positional information at observation points and geophysical information (from our own South China Sea gravity anomaly model (SCSGA) V1.0 and bathymetry model ETOPO1) at gr

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Wang, Shizhang, and Xiaoshi Qiao. "A local data assimilation method (Local DA v1.0) and its application in a simulated typhoon case." Geoscientific Model Development 15, no. 23 (2022): 8869–97. http://dx.doi.org/10.5194/gmd-15-8869-2022.

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Abstract. Integrating the hybrid and multiscale analyses and the parallel computation is necessary for current data assimilation schemes. A local data assimilation method, Local DA, is designed to fulfill these needs. This algorithm follows the grid-independent framework of the local ensemble transform Kalman filter (LETKF) and is more flexible in hybrid analysis than the LETKF. Local DA employs an explicitly computed background error correlation matrix of model variables mapped to observed grid points/columns. This matrix allows Local DA to calculate static covariance with a preset correlatio

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Khade, V. M., J. A. Hansen, J. S. Reid, and D. L. Westphal. "Ensemble filter based estimation of spatially distributed parameters in a mesoscale dust model: experiments with simulated and real data." Atmospheric Chemistry and Physics Discussions 12, no. 11 (2012): 28837–89. http://dx.doi.org/10.5194/acpd-12-28837-2012.

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Abstract. The Ensemble Adjustment Kalman Filter (EAKF) is used to estimate the erodibility fraction parameter field in a coupled meteorology and dust aerosol model (Coupled Ocean Atmosphere Mesoscale Prediction System-COAMPS) over the Sahara desert. Erodibility is often employed as the key parameter to map dust source. It is used along with surface winds (or surface wind stress) to calculate dust emissions. Using the Saharan desert as a test bed, a perfect model Observation System Simulation Experiments (OSSEs) with 40 ensemble members, and observations of aerosol optical depth (AOD), the EAKF

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Khade, V. M., J. A. Hansen, J. S. Reid, and D. L. Westphal. "Ensemble filter based estimation of spatially distributed parameters in a mesoscale dust model: experiments with simulated and real data." Atmospheric Chemistry and Physics 13, no. 6 (2013): 3481–500. http://dx.doi.org/10.5194/acp-13-3481-2013.

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Abstract. The ensemble adjustment Kalman filter (EAKF) is used to estimate the erodibility fraction parameter field in a coupled meteorology and dust aerosol model (Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS)) over the Sahara desert. Erodibility is often employed as the key parameter to map dust source. It is used along with surface winds (or surface wind stress) to calculate dust emissions. Using the Saharan desert as a test bed, a perfect model Observation System Simulation Experiments (OSSEs) with 40 ensemble members, and observations of aerosol optical depth (AOD), the EA

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Lakshmanan, Valliappa, and Travis Smith. "Data Mining Storm Attributes from Spatial Grids." Journal of Atmospheric and Oceanic Technology 26, no. 11 (2009): 2353–65. http://dx.doi.org/10.1175/2009jtecha1257.1.

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Abstract A technique to identify storms and capture scalar features within the geographic and temporal extent of the identified storms is described. The identification technique relies on clustering grid points in an observation field to find self-similar and spatially coherent clusters that meet the traditional understanding of what storms are. From these storms, geometric, spatial, and temporal features can be extracted. These scalar features can then be data mined to answer many types of research questions in an objective, data-driven manner. This is illustrated by using the technique to an

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Ignatov, Petr, Nail Zaripov, Konstantin Novikov, and Alexander Tolstov. "Drag folds in sedimentary rocks hosting kimberlites, West Yakutia." Ores and metals, no. 3 (November 3, 2021): 82–91. http://dx.doi.org/10.47765/0869-5997-2021-10020.

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Drag folds were revealed in Lower Paleozoic sedimentary strata of Mirny, Nakyn and Syuldyukar diamondiferous fields, West Yakutia. They consist of minor anticlinal forms (3-5 to 15-20 cm thick) and cut marl, clayey limestone and dolomite bands located between monolith seams of carbonate rocks. Some folds as monocline, flexures and S- or Z-shaped folds reflect the degree of shearrelated interlayer offset. Drag folds are among shear zone occurrences including microfaults, slickensides with slip groove horizontal planes, and schistosity zones. Drag folds reflect local extension points while schis

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Cummings, James A., and Ole Martin Smedstad. "Ocean Data Impacts in Global HYCOM*." Journal of Atmospheric and Oceanic Technology 31, no. 8 (2014): 1771–91. http://dx.doi.org/10.1175/jtech-d-14-00011.1.

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Abstract The impact of the assimilation of ocean observations on reducing global Hybrid Coordinate Ocean Model (HYCOM) 48-h forecast errors is presented. The assessment uses an adjoint-based data impact procedure that characterizes the forecast impact of every observation assimilated, and it allows the observation impacts to be partitioned by data type, geographic region, and vertical level. The impact cost function is the difference between HYCOM 48- and 72-h forecast errors computed for temperature and salinity at all model levels and grid points. It is shown that routine assimilation of lar

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Sirmacek, B., and R. Lindenbergh. "AUTOMATIC CLASSIFICATION OF TREES FROM LASER SCANNING POINT CLOUDS." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences II-3/W5 (August 19, 2015): 137–44. http://dx.doi.org/10.5194/isprsannals-ii-3-w5-137-2015.

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Development of laser scanning technologies has promoted tree monitoring studies to a new level, as the laser scanning point clouds enable accurate 3D measurements in a fast and environmental friendly manner. In this paper, we introduce a probability matrix computation based algorithm for automatically classifying laser scanning point clouds into ’tree’ and ’non-tree’ classes. Our method uses the 3D coordinates of the laser scanning points as input and generates a new point cloud which holds a label for each point indicating if it belongs to the ’tree’ or ’non-tree’ class. To do so, a grid surf

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Brito, Cristiano de Souza, and Marcelo Almeida Bairral. "Triangle similarity: interactions in meshes and slider." Revista Internacional de Pesquisa em Educação Matemática 13, no. 3 (2023): 1–21. http://dx.doi.org/10.37001/ripem.v13i3.3543.

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This article discusses the interactions of (prospective) teachers when performing two tasks in a multiuser, online, virtual, and synchronous version of GeoGebra, the VMTcG. When analyzing the data, the discursive aspects, the modalities of dragging points and the categories of signs present in the process of semiotic mediation are considered. The first episode involves the use of the square grid in a task on congruence of triangles, and the second one, a task on the similarity ratio from a slider. The data make it possible to conclude that the thought processes related to the use of the checke

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Hu, Jingwen, Gui-Song Xia, and Hong Sun. "An SRTM-Aided Epipolar Resampling Method for Multi-Source High-Resolution Satellite Stereo Observation." Remote Sensing 11, no. 6 (2019): 678. http://dx.doi.org/10.3390/rs11060678.

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Binocular stereo observation with multi-source satellite images used to be challenging and impractical, but is now a valuable research issue with the introduction of powerful deep-learning-based stereo matching approaches. However, epipolar resampling, which is critical for binocular stereo observation, has rarely been studied with multi-source satellite images. The main problem is that, under the multi-source stereo mode, the epipolar-line-direction (ELD) at an image location may vary when computed with different elevations. Thus, a novel SRTM (Shuttle Radar Topography Mission)-aided approach

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Li, Jia, Huan Lin, Duo Qiang Zhang, and Xiao Lu Xue. "Extracting Geometric Edges from 3D Point Clouds Based on Normal Vector Change." Applied Mechanics and Materials 571-572 (June 2014): 729–34. http://dx.doi.org/10.4028/www.scientific.net/amm.571-572.729.

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Normal vector of 3D surface is important differential geometric property over localized neighborhood, and its abrupt change along the surface directly reflects the variation of geometric morphometric. Based on this observation, this paper presents a novel edge detection algorithm in 3D point clouds, which utilizes the change intensity and change direction of adjacent normal vectors and is composed of three steps. First, a two-dimensional grid is constructed according to the inherent data acquisition sequence so as to build up the topology of points. Second, by this topological structure prelim

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Zamo, Michaël, Liliane Bel, Olivier Mestre, and Joël Stein. "Improved Gridded Wind Speed Forecasts by Statistical Postprocessing of Numerical Models with Block Regression." Weather and Forecasting 31, no. 6 (2016): 1929–45. http://dx.doi.org/10.1175/waf-d-16-0052.1.

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Abstract Numerical weather forecast errors are routinely corrected through statistical postprocessing by several national weather services. These statistical postprocessing methods build a regression function called model output statistics (MOS) between observations and forecasts that is based on an archive of past forecasts and associated observations. Because of limited spatial coverage of most near-surface parameter measurements, MOS have been historically produced only at meteorological station locations. Nevertheless, forecasters and forecast users increasingly ask for improved gridded fo

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Wang, Xiao Long, and Hong Tao Luo. "The Hanging Point of the Spatial Grid Structure High Strength Bolt Fatigue Notch Effect Analysis." Advanced Materials Research 788 (September 2013): 554–57. http://dx.doi.org/10.4028/www.scientific.net/amr.788.554.

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In recent years, the advantages of light weight steel structure with its widely used in long-span space truss structure industrial workshop. Unlike traditional bridge crane, space truss structure plant can use suspension crane, so the dynamic load of fatigue problem worthy of further study[. The fatigue of the space truss structure including: structure component fatigue, tired of hanging lifting point. At present, the fatigue test is the most reliable research method. This article uses the ANSYS software for welding the hollow ball nodes [2] hanging points of high strength bolts in finite elem

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Horn, Berthold K. P. "Round-Trip Time Ranging to Wi-Fi Access Points Beats GNSS Localization." Applied Sciences 14, no. 17 (2024): 7805. http://dx.doi.org/10.3390/app14177805.

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Wi-Fi round-trip time (RTT) ranging has proven successful in indoor localization. Here, it is shown to be useful outdoors as well—and more accurate than smartphone code-based GNSS when used near buildings with Wi-Fi access points (APs). A Bayesian grid with observation and transition models is used to update a probability distribution of the position of the user equipment (UE). The expected value (or the mode) of this probability distribution provides an estimate of the UE location. Localization of the UE using RTT ranging depends on knowing the locations of the Wi-Fi APs. Determining these po

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Maisto, Maria Antonia, Mehdi Masoodi, Giovanni Leone, Raffaele Solimene, and Rocco Pierri. "Scattered Far-Field Sampling in Multi-Static Multi-Frequency Configuration." Sensors 21, no. 14 (2021): 4724. http://dx.doi.org/10.3390/s21144724.

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This paper deals with an inverse scattering problem under a linearized scattering model for a multi-static/multi-frequency configuration. The focus is on the determination of a sampling strategy that allows the reduction of the number of measurement points and frequencies and at the same time keeping the same achievable performance in the reconstructions as for full data acquisition. For the sake of simplicity, a 2D scalar geometry is addressed, and the scattered far-field data are collected. The relevant scattering operator exhibits a singular value spectrum that abruptly decays (i.e., a step

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Chen, Z. H., J. Zhu, and N. Zeng. "Improved simulation of group averaged CO<sub>2</sub> surface concentrations using GEOS-Chem and fluxes from VEGAS." Atmospheric Chemistry and Physics Discussions 13, no. 1 (2013): 2243–71. http://dx.doi.org/10.5194/acpd-13-2243-2013.

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Abstract. CO2 measurements have been combined with simulated CO2 distributions from a transport model in order to produce the optimal estimates of CO2 surface fluxes in inverse modeling. However one persistent problem in using model-observation comparisons for this goal relates to the issue of compatibility. Observations at a single site reflect all underlying processes of various scales that usually cannot be fully resolved by model simulations at the grid points nearest the site due to lack of spatial or temporal resolution or missing processes in models. In this article we group site observ

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Мөнхбат, Б., П. Гомболүүдэв, С. Эрдэнэсүх та Д. Сандэлгэр. "ANUSPLIN статистик загвар ашиглан Монгол орны агаарын температур, хур тунадасыг (1991-2020) өндөр нарийвчлалтай торын зангилааны цэгээр тооцоолох нь". Geographical Issues 22, № 1 (2022): 92–102. http://dx.doi.org/10.22353/.v22i1.553.

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The main objectives of this study were to use the statistical model (ANUSPLIN) to calculate the updated norms Mongolia of air temperature and precipitation (average for 1991-2020 according to the World Meteorological Organization) with high spatial accuracy for any grid, and to perform objective analysis in observation data. GTOPO30 (global digital elevation model, DEM) elevation grid data with 30-arc seconds (1 km) accuracy for estimating the mountain and orographic conditions of Mongolia, and monthly climate data of 137 meteorological stations of the National Agency of Meteorological and Env

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Nolan, Michael W., Tracy L. Gieger, Alexander A. Karakashian, et al. "Outcomes of Spatially Fractionated Radiotherapy (GRID) for Bulky Soft Tissue Sarcomas in a Large Animal Model." Technology in Cancer Research & Treatment 16, no. 3 (2017): 357–65. http://dx.doi.org/10.1177/1533034617690980.

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GRID directs alternating regions of high- and low-dose radiation at tumors. A large animal model mimicking the geometries of human treatments is needed to complement existing rodent systems (eg, microbeam) and clarify the physical and biological attributes of GRID. A pilot study was undertaken in pet dogs with spontaneous soft tissue sarcomas to characterize responses to GRID. Subjects were treated with either 20 Gy (3 dogs) or 25 Gy (3 dogs), delivered using 6 MV X-rays and a commercial GRID collimator. Acute toxicity and tumor responses were assessed 2, 4, and 6 weeks later. Acute Radiation

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Crocker, Ric, Jan Maksymczuk, Marion Mittermaier, Marina Tonani, and Christine Pequignet. "An approach to the verification of high-resolution ocean models using spatial methods." Ocean Science 16, no. 4 (2020): 831–45. http://dx.doi.org/10.5194/os-16-831-2020.

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Abstract. The Met Office currently runs two operational ocean forecasting configurations for the North West European Shelf: an eddy-permitting model with a resolution of 7 km (AMM7) and an eddy-resolving model at 1.5 km (AMM15). Whilst qualitative assessments have demonstrated the benefits brought by the increased resolution of AMM15, particularly in the ability to resolve finer-scale features, it has been difficult to show this quantitatively, especially in forecast mode. Applications of typical assessment metrics such as the root mean square error have been inconclusive, as the high-resoluti

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Mile, Máté, Stephanie Guedj, and Roger Randriamampianina. "Exploring the footprint representation of microwave radiance observations in an Arctic limited-area data assimilation system." Geoscientific Model Development 17, no. 17 (2024): 6571–87. http://dx.doi.org/10.5194/gmd-17-6571-2024.

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Abstract. The microwave radiances are key observations, especially over data-sparse regions, for operational data assimilation in numerical weather prediction (NWP). An often applied simplification is that these observations are used as point measurements; however, the satellite field of view may cover many grid points of high-resolution models. Therefore, we examine a solution in high-resolution data assimilation to better account for the spatial representation of the radiance observations. This solution is based on a footprint operator implemented and tested in the variational assimilation s

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Nasrul, Besri, Nurhidayati, Muhamad Teguh Pratama, et al. "Peat depth mapping using grid interpolation from terrestrial peat drilling points data: A case study in Zamrud National Park." BIO Web of Conferences 99 (2024): 05002. http://dx.doi.org/10.1051/bioconf/20249905002.

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Zamrud National Park is the peak of the peat dome in the Kampar Peninsula. Peat depth data is needed as a baseline to maintain the balance of the water reservoir and carbon stock. Currently, available peat depth data is predictive photogrammetric data. Soil survey activities need to be carried out to provide accurate and up-to-date data. This research aims to map the peat depth using the best grid interpolation technique. Peat depth measurements were carried out terrestrially, while peat depth mapping used inverse distance weighted, kriging, and spline interpolation techniques. Drilling observ

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Blouet, Sylvain, l. Bramanti, and Katell Guizien. "ENVIRONMENTAL NICHE MODELLING OF FIVE GORGONIAN SPECIES WITHIN THE SHALLOW ROCKY HABITAT OF THE FRENCH MEDITERRANEAN COAST." Vie et Milieu / Life & Environment 7, no. 1-2 (2024): 1–43. http://dx.doi.org/10.57890/viemilieu/2024.74-1/2:1-44.

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Engineer species, such as gorgonians, provide several ecosystem services and play a significant role in the maintenance of biodiversity. We tested an ecological niche modelling an approach using a unique dataset of spatialized inventories on a regular grid (< 800 m) replicated in 2013 and 2020 along 450 km of coastline for five gorgonian species commonly found in the Mediterranean shallow habitats (10-50 m deep). Ten non-correlated environmental predictors derived from the most advanced geomorphological and hydrological data were used to assess the ecological niche of the five species using

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Horn, Berthold K. P. "Indoor Localization Using Uncooperative Wi-Fi Access Points." Sensors 22, no. 8 (2022): 3091. http://dx.doi.org/10.3390/s22083091.

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Indoor localization using fine time measurement (FTM) round-trip time (RTT) with respect to cooperating Wi-Fi access points (APs) has been shown to work well and provide 1–2 m accuracy in both 2D and 3D applications. This approach depends on APs implementing the IEEE 802.11-2016 (also known as IEEE 802.11mc) Wi-Fi standard (“two-sided” RTT). Unfortunately, the penetration of this Wi-Fi protocol has been slower than anticipated, perhaps because APs tend not to be upgraded as often as other kinds of electronics, in particular in large institutions—where they would be most useful. Recently, Googl

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Li, Weiming, Zhiqiang Du, Li Wang, and Tiancheng Zhou. "Evaluation of the Monitoring Capabilities of Remote Sensing Satellites for Maritime Moving Targets." ISPRS International Journal of Geo-Information 13, no. 9 (2024): 325. http://dx.doi.org/10.3390/ijgi13090325.

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Although an Automatic Identification System (AIS) can be used to monitor trajectories, it has become a reality for remote sensing satellite clusters to monitor maritime moving targets. The increasing demand for monitoring poses challenges for the construction of satellites, the monitoring capabilities of which urgently need to be evaluated. Conventional evaluation methods focus on the spatial characteristics of monitoring; however, the temporal characteristics and the target’s kinematic characteristics are neglected. In this study, an evaluation method that integrates the spatial and temporal

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Horton, Simon, and Pascal Haegeli. "Using snow depth observations to provide insight into the quality of snowpack simulations for regional-scale avalanche forecasting." Cryosphere 16, no. 8 (2022): 3393–411. http://dx.doi.org/10.5194/tc-16-3393-2022.

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Abstract. The combination of numerical weather prediction and snowpack models has potential to provide valuable information about snow avalanche conditions in remote areas. However, the output of snowpack models is sensitive to precipitation inputs, which can be difficult to verify in mountainous regions. To examine how existing observation networks can help interpret the accuracy of snowpack models, we compared snow depths predicted by a weather–snowpack model chain with data from automated weather stations and manual observations. Data from the 2020–2021 winter were compiled for 21 avalanche

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Ali, Abdullah, Gumilang Deranadyan, and Iddam Hairuly Umam. "An Enhancement to The Quantitative Precipitation Estimation Using Radar-Gauge Merging." International Journal of Remote Sensing and Earth Sciences (IJReSES) 17, no. 1 (2020): 65. http://dx.doi.org/10.30536/j.ijreses.2020.v17.a3316.

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Quantitative Precipitation Estimation (QPE) is quite important information for the hydrology fields and has many advantages for many purposes. Its dense spatial and temporal resolution can be combined with the surface observation to enhance the accuracy of the estimation. This paper presents an enhancement to the QPE product from BMKG weather radar network at Surabaya by adjusting the estimation value form radar to the real data observation from rain gauge. A total of 58 rain gauge is used. The Mean Field Bias (MFB) method used to determine the correction factor through the difference between

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Gel, Yulia R. "Comparative Analysis of the Local Observation-Based (LOB) Method and the Nonparametric Regression-Based Method for Gridded Bias Correction in Mesoscale Weather Forecasting." Weather and Forecasting 22, no. 6 (2007): 1243–56. http://dx.doi.org/10.1175/2007waf2006046.1.

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Abstract The comparative analysis of three methods for objective grid-based bias removal in mesoscale numerical weather prediction models is considered. The first technique is the local observation-based (LOB) method that extends further the approaches of several recent studies and is focused on utilizing the information obtained from meteorological stations or neighbor grid points in the proximity of a site of interest. The bias at a site of interest might then be considered as a spatiotemporal function of the weighted information on the past biases observed in the cluster of neighbors during

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Cai, Youming, Zheng Li, and Xu Cai. "Optimal Inertia Reserve and Inertia Control Strategy for Wind Farms." Energies 13, no. 5 (2020): 1067. http://dx.doi.org/10.3390/en13051067.

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It is important to reduce the impact of the high penetration of wind power into the electricity supply for the purposes of the security and stability of the power grid. As such, the inertia capability of wind farms has become an observation index. The existing control modes cannot guarantee the wind turbine to respond to the frequency variation of the grid, hence, it may lead to frequency instability as the penetration of wind power gets much higher. For the stability of the power grid, a simple and applicable method is to realize inertia response by controlling wind farms based on a high-spee

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BOUTHIBA, Youssouf, Billel MEGHNI, Rachid TALEB, and Ali BELHAMRA. "Power Management Optimization of HES Connected to the Grid-Based IEMS." International Journal of Emerging Technology and Advanced Engineering 13, no. 10 (2023): 6–29. http://dx.doi.org/10.46338/ijetae1023_02.

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This paper presents a study of a grid-connected hybrid energy system (HES) consisting of photovoltaic/wind/fuel cell/battery/supercapacitor (SC). The purpose of using SC with the battery is to create a hybrid energy storage system (HESS) with high energy density. To prevent overcharging of the latter, a discharge load was employed (in our case, a resistance). The objectives of this research are to operate the photovoltaic generator and the wind power generator at their maximum power points by applying the perturbation and observation (P&O) technique and the tip speed ratio (TSR) technique,

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Tsai, Men-Shen, and Yen-Kuang Lin. "Applying the Geometric Features of Cumulative Sums to the Development of Event Detection." Energies 16, no. 20 (2023): 7207. http://dx.doi.org/10.3390/en16207207.

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As a result of the severe energy shortage and the greenhouse effect, experts worldwide have been devoted to solving energy management problems. Smart grid construction is an essential technology for mastering energy allocation. Smart grids enable end users to adjust their energy consumption via incentive measures, reduce the frequency of power supply instability, and improve energy efficiency. Non-intrusive load monitoring (NILM) is a vital technology for smart grid construction. One of the fundamental steps of NILM is event detection. Proper event detection can increase the accuracy of load i

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