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The article focuses on nowcasting systems in European National Meteorological Services (NMS), defining nowcasting and its unique characteristics, including methods, and applications. Topics include the EUMETNET Nowcasting program's phases, various types of nowcasting systems (object-oriented, field-oriented radar and satellite, NWP models), and seamless systems (deterministic and probabilistic), highlighting their development, methodologies, and applications across European NMSs.

Academic journals differ only in some criteria and formal aspects from cultural or literary journals. In both cases, they install or consolidate theoretical and critical lines. The anniversary of Anclajes offers an opportunity to review some of these lines in relation to literary studies on contemporaneity. [ABSTRACT FROM AUTHOR]

In recent years there has been a growing interest in detecting, delimit and inventory wetlands under an ecohydrogeomorphic approach to expand the knowledge of these ecosystems and enable the development of management guidelines for their use. The aim of this article is detect and delimit those sectors that reflect favorable ecohydrogeomorphic conditions to define them as wetlands in a sector of the Alsina basin located in the southwest of the province of Buenos Aires, Argentina. A complementary methodology was applied between optiand radar images, consisting of the use of a digital AlosPalsar elevation model and Sentinel 2 A and Sentinel 1 images. A flood pulse was addressed in the shallow lake that occurred in 2017. The wet events reflect the operation of the shallow lake and the wetland systems. Biophysical changes that occurred in the perilaguna sectors were analyzed in reference to the entry of precipitations. The results verified the presence of different types of wetlands between the shallow lake and its perilagunar area that during a flood function as a hybrid ecosystem. [ABSTRACT FROM AUTHOR]

The aim of this study is to estimate and map soil moisture (SM) from Cosmo-Skymed (X band) images acquired over an agricultural basin located in the center of the province of Buenos Aires, Argentina (Latitude: 37oS; Longitude: 60oW approximately). The adopted approach is empirical, with a correlation between backscattering coefficient (-0) and soil moisture (SM) measures, obtained simultaneously with a satellite pass. Surface (0 to 10 cm) soil moisture was measured by means of the gravimetric method in 15 agricultural parcels (sites). The linear relation between radar signal backscattering (0) and field measured SM [SM(%) = b+a.0(dB)] shows diverse coefficients and adjustments (r2), depending on orbit direction and polarization (from r² = 0, 28 for VV Ascending to r² = 0, 69 for HH Descending). Using corresponding relation equations, images were translated from 0 into SM (%), obtaining the SM maps (for each polarization and orbit pass). Cross-validation between measured and calculated SM was performed, computing the Root Mean Square Error (RMSE) and Normalized Mean Square Error (NMSE). Better results were obtained from Descending images, with 6,3% < RMSE < 6,9% and 1,6 < NMSE < 2,0 %). Results are compared with other experiences, and future expectations are outlined. [ABSTRACT FROM AUTHOR]

During determination of coverage zones of radio mobile services, transmitters of television and others emitters of ultrashort-waves and, also, when is realized the analysis of radio relay lines or radar range, is necessary to predict the intensity E of electric field taking on account Earth's sphericity. This prediction is realized, in illuminated region or zone, using earth's plane expressions, but taking reduced heights instead of real heights. Reduced heights (RH) diminish when distance R grows, but is more notable the affectations when we are near the limit of maximum direct visibility distance: Ro. The limit distance Ro is an important magnitude during determination of coverage in cited radio services. In this article are summarized expressions present in references but the main objective is propose another derivate expressions that depends of relatives distances ζ and relation m of antennas heights. With this proposition is wished to facilitate the analysis and calculation of RH, but with normalized dependences, avoiding unnecessary recurrences and with reduced processing time of computing calculations. [ABSTRACT FROM AUTHOR]

The research aims to develop and validate an instrument to characterize the impact level, in the healthcare institutions, of the application of the four essential dimensions of the Radar of innovation: the offers of the institution (what?), the clients (who?), the processes (how?) and the points of presence (where?). A mixed exploratory study was chosen. Through the bibliographic review and the discussion with a panel of 11 experts, the content of the instrument of 49 items was constructed and approved on a 5-point Likert scale to characterize the use of innovation in the healthcare institutions; the construct and reliability were validated by applying a pilot test to 33 participants and the study of the results obtained for each of the dimensions of the innovation radar was carried out using exploratory factor analysis (AFE) and Cronbach's alpha. The research proposes an instrument whose content and construct were validated for the final factorial structure composed of 43 items, included in 13 factors or criteria; through statistical analysis, high reliability is demonstrated for the four dimensions proposed by the Radar of innovation. [ABSTRACT FROM AUTHOR]

The state's administration, concerned about the importance of having an efficient Judicial System attempt to provide it with the required resources. Nevertheless, due to the state division in autonomies remarkable inequalities are produced between them. Along this essay, principally focused in Andalusian autonomous community, a comparison of the development of its judicial system efficiency will be analysed along with the rest of Spain. Given the specificities of each jurisdiction, the analysis will be done at a global level and later, specified in each jurisdiction. Via the radar chart's technique improvements will be analysed throughout the following periods, 2009-2012, 2012-2015 y 2016-2018, placing Andalusia in the national context. The results show that, globally in the 2009-2012 period, Andalusia follows the improvement path as well as the rest of Spain, notwithstanding the Andalusian situation decays in the following period, 2012-2015, being the civil jurisdiction the most affected one. With an unprecedented use of this technique in justice, a new investigation field is discovered to analyse the public sector, whose proper function conditionate other ones and has direct economic implications for the country. [ABSTRACT FROM AUTHOR]

The objective of this work was to identify flood zones in the city of Santiago de Cali Colombia, through historical information and RADAR images. During the process Sentinel 1 images pre and post event were used, and reports of hydrometeorological phenomena (1986-2018) were revisited. The method used corresponds to the framework named methodological complementarity and was carried out with the documentary review, fieldwork and the digital treatment of data based on supervised classification. The results of documentary review and fieldwork indicate the occurrence of 766 events associated with floods that have affected 186 neighborhoods in a period of 32 years. In addition to this, digital image processing identified 2082, 25 hectares of flood-plains, with overall reliability of 89 percent. Kappa index of 0.76 percent. It is important to note that the majority of water plates were located in areas adjacent to the Cauca, Cali and Interceptor Sur and Oriental channels. [ABSTRACT FROM AUTHOR]

Software Defined Radio (SDR) is a technology with recognition in Telecommunication industry because of its capacity of developing reconfigurable communication systems. This paper presents the implementation and field-testing evaluation for a low-cost radar system using the gr-radar toolbox created into the version 3.7.4 of GNU Radio. Tests allowed to measure distances and velocities of a target in movement. Velocity estimation errors were obtained with 1.8% and 3.22% in a round trip. Range estimation errors were also obtained with 1.56% and 2.75% in a round trip. Radar system was configured to transmit at 2.4 GHz with Multiple CW technique. The test scenario was the Nueva Granada Military University Campus in Colombia. The results are oriented toward using this tools for deepening on basic Radar principles with low-cost devices. [ABSTRACT FROM AUTHOR]

Central and northern Argentina are one of the most favorable regions for the occurrence of high impact meteorological events. These events can generate intense precipitation, large hail and/or extreme winds, causing enormous damages to the population. Therefore, it is essential to make progress in improving very short-term weather forecasts (0-6 hours) of this type of events. In this work, a very-short term forecast model based on extrapolation techniques of the reflectivity field is developed and evaluated. This method assumes that precipitating systems can be described from their movement, estimated from the latest available information and consists in two steps. Firstly, it estimates a vector field describing the displacement of the reflectivity field. Secondly, this motion field is used to extrapolate the reflectivity field displacement using a semi-lagrangian advective method. In this work we compare different variants in the algorithm that estimates the displacement of the reflectivity field and its impact on 2-hr reflectivity field forecasts. Experiments were performed for a case that represents the evolution of a convective system over central Argentina. We use synthetic radar data generated from a numerical simulation with high resolution that explicitly resolved convection dynamics. [ABSTRACT FROM AUTHOR]

In coastal radar, In addition to a direct radiation pattern, a level of secondary lobes or small parasites is required. With the aim of reduce the width of the half-power beam of the original FURUNO radar antenna to 3o, in this article the reader is shown the design of an offset parabolic cylindrical reflector antenna in the X band at 9.4 GHz. The analysis of the antenna in two planes is proposed separately. In the vertical plane, a sector horn antenna is proposed as an excitation antenna. In the horizontal plane, a uniform linear array of 129 elements is proposed. From the results obtained it is seen how with the presented design a greater directivity is achieved, an increase of the gain in approximately 8dB which results in an increase in the noise Gain-Temperature ratio, secondary lobe levels of -25 dB and in addition, theoretically, it is possible to increase the scope of the coastal radar by more than twice. [ABSTRACT FROM AUTHOR]

This article presents the Bose sonar sequence and we will show that it satisfy some of the characteristics of know sonar sequences, which are related by some geometric and algebraic properties of the Sidon sets. We specify a methodology for obtaining the Bose sequence using the Matlab software, this sequeces can be applied to various fields of engineering that involve Radar and Sonar techniques. [ABSTRACT FROM AUTHOR]

The increasing complexity of radar devices, and the variety of naval and coastal scenarios in which they need to be deployed, motivates the need for the stochastic modelling of the sea clutter, which will contribute to the assessment of the system before the implementation. Specifically, when radars are placed on aircrafts or elevated locations, the statistical distribution of the background echoes gets modified and therefore differs from the one commonly assumed for low grazing angles. For the accurate representation of the sea clutter observed at medium and high grazing angles, the authors modelled in MATLAB the Weibull-Weibull and K-K mixed distributions, which are frequently used in the literature. The implemented functions provide an easy access to the handling of density, cumulative distribution and survival functions, as well as the generation of random variables and the estimation of central and algebraic moments of the addressed distributions. Besides, additional functions were included, enabling the validation of the code by comparison with the results provided by other investigations and through the interaction of the functions. The created code models distributions which are commonly ignore by most software for statistical simulation, due to their specific application in radar related studies. Therefore, the current research is expected to lead to the conception of enhanced detection solutions adapted to different operation scenarios, also contributing to the creation of a framework specialized in radar clutter. [ABSTRACT FROM AUTHOR]

The sea clutter is a random interfering signal that appears in radar readings caused by the reflection experienced by the emission over the sea surface. After a deep review on the related literature, 23 statistical distributions or models were found for representing sea clutter. The authors classified these models into five groups taking into account the frequency of use and the importance of each distribution. The performed review has two main achievements. Firstly, the mathematical expressions for the distributions were gathered and unified, which contributes to the homogenization of the studies. Secondly, a wide set of candidate distributions were offered enabling the execution of new investigations related to the fit of statistical distributions to empirical clutter data. The investigation strongly recommends the use of 15 distributions, while common studies rarely used more than four. [ABSTRACT FROM AUTHOR]

Images of microwave sensors such as radar help to have well-timed data of land areas, which allow to produce basic mapping or thematic information. The radar sensors are more complex in their acquisition geometry. Therefore, this research defines criteria and procedures to obtain more precise estimates in the process of ortho-rectification of Synthetic Aperture Radar images. The methodology involved several processes that emphasized the ortho-rectification of SAR images, applying ephemeris adjustment with DGNSS ground control points. The distortions by relief effect were corrected by using a DEM suitable to the working scale in an area of North Central Venezuela. Subsequently, the cartographic product validation was performed in order to verify that it is within the mapping accuracy standards under different conditions of relief. As a result, a product at 1:50,000 scale which may be used in engineering applications and in any other application in Geomatics was obtained. The final result of the research is reflected in a synthesis of criteria and procedures for the planimetric control in the generation of orthoimages. [ABSTRACT FROM AUTHOR]

The sea clutter is an interfering signal that appears in radar systems operating in oceanic or offshore scenarios. The author simulated in MATLAB the K distribution, widely recognized as the best model for sea clutter because it takes into account the two fluctuation mechanisms coexisting in the background signal. The implementation allows an easy access to the handling of probability distribution functions, generating functions, moments, goodness of fit algorithms and parameter estimation techniques. Mathematical expressions and notations for computer functions were defined as a contribution to the unification of radar clutter studies related to the K distribution. The solution is a start point for the development of new detection schemes by the Radar Research Team from the CUJAE's Electrical Engineering Faculty and contributes to the realization of the MATE-CFAR 2 library. [ABSTRACT FROM AUTHOR]

Over the last years new radar systems uses have been arisen, both civil and military field. These further uses demand more data about the radar targets. Up to now, was enough to know its location, rough velocity and an approximate motion direction, even though, now there is a growing need of security and control, which requires higher accuracy measuring these targets's characteristics, even to obtain a "radar image" trying to classify or identify it. This article explains how to obtain ISAR radar images, especially using a Continuous Wave Linear Frequency Modulated Radar (CWLFM), not only in a theoretical way but also showing the results achieved in a lot of different experiments made during a four years research-project sponsored by the Spanish Ministry of Science and Technology, emphasizing the high quality of the images obtained, and also, that any kind of control or collaboration was expected from the target. Making the result more important from a practical point of view, opening up much more possible applications to radar systems. [ABSTRACT FROM AUTHOR]

The radar technique prospects the subsoil with electromagnetic waves with frequencies between 10 and 1200 Mhz. A reflection radar image shows contrasts of the subsoil generated by its inhomogeneous electromagnetic properties. The velocity of the dielectric constant, correlated with mineral fabric, structure and water contained in rocks. Meanwhile lab assays, correlations between this properties for sand, cloy and a mixture of the, were stablished. [ABSTRACT FROM AUTHOR]

The La Mojana subregion has historically presented problems of flooding, caused by overflowing of the rivers that cross it, generating problems in agricultural production and with it in the quality of life of its inhabitants. The objective of the study was to use radar images to determine the affectation by floods in the municipalities of La Mojana with the largest area planted with rice (Oryza sativa L.). For this, the SNAP 8.0.0 and QGIS 3.20 software were used for the preprocessing of the radar images and the Python 3.7 computational programming language. to implement decision trees. As a result of the study, the areas affected by floods in the La Mojana subregion were identified and quantified at the municipality level with 12-day intervals and with an accuracy greater than 97%. [ABSTRACT FROM AUTHOR]