Vitali Diaz

Delft University of Technology | TU · Department of Architectural Engineering & Technology

Cloud-to-cloud (C2C) distance calculations are frequently performed as an initial stage in change detection and spatiotemporal analysis with point clouds. There are various methods for calculating C2C distance, also called inter-point distance, which refers to the distance between two corresponding point clouds captured at different epochs. These m...

Document via TU Delft, copy and paste link into your browser:[https://research.tudelft.nl/files/181226651/THREEDIMENSIONAL_CLUSTERING_IN_THE_CHARACTERIZATION_OF_SPATIOTEMPORAL.pdf] Abstract: In its three-dimensional (3-D) characterization, drought is an event whose spatial extent changes over time. Each drought event has an onset and end time, a lo...

Point distance calculations are frequently performed as an initial stage in change detection and spatiotemporal analysis with point clouds. There are various methods for calculating inter-point distance or the distance between two corresponding point clouds. These methods can be classified from simple to complex, with more steps and calculations re...

Point cloud data allows detailed analysis due to the massive amount of information that can be collected. However, most existing spatio-temporal analysis methods and examples have been developed/applied to raster and vector data. Thus, the use of point cloud data has not been fully explored. Sandy coasts present dynamic morphologies whose study and...

Droughts evolve in space and time without following borders or pre-determined temporal constraints. Here, we present a new database of drought events built with a three-dimensional density-based clustering algorithm. The chosen approach is able to identify and characterize the spatio-temporal evolution of drought events, and it was tuned with a sup...

Spatiotemporal analysis is important for spotting changes, hotspots, and phenomena across space and time. Such assessments' accuracy depends on temporal and geographical resolution, which is especially important for specific cases. While point cloud data provides extensive details, many spatio-temporal analysis methods are designed for raster and v...

Open access via TUDelft: (https://pure.tudelft.nl/ws/portalfiles/portal/161265730/978_3_031_14096_9_10.pdf) Abstract: Drought directly impacts the living organisms and environment, and thereby, its assessment is essential. Different drought indices require different data, which can be obtained based on models or in-situ measurements, demanding a s...

Drought assessment and monitoring are essential for its proper management. Drought indices play a fundamental role in this. This research introduces the Wet-environment Evapotranspiration and Precipitation Standardized Index (WEPSI) for drought assessment and monitoring. WEPSI incorporates water supply and demand into the drought index calculation....

Climate change has increased the possibility of more severe and prolonged droughts worldwide, which requires innovative methods to predict their impacts on different sectors such as agriculture. Crop growth models calculate yield and variables related to plant development and are used for crop yield estimation, a useful variable for monitoring drou...

Droughts evolve in space and time without following borders or pre-determined temporal constraints. Here, we present a new database of drought events built with a three-dimensional density-based clustering algorithm. The chosen approach is able to track the spatio-temporal evolution of an event, and it was tuned against a set of past global drought...

Point cloud is made up of a multitude of three-dimensional (3D) points with one or more attributes attached. Point cloud is the third data paradigm in addition to the well-established object (vector) and gridded (raster) representations, since point cloud data can be directly collected, computed, stored, and analyzed without converting to other typ...

Point cloud is made up of a multitude of three-dimensional (3D) points with one or more attributes attached. Point cloud is the third data paradigm in addition to the well-established object (vector) and gridded (raster) representations, since point cloud data can be directly collected, computed, stored, and analyzed without converting to other typ...

Studies of drought have increased in light of new data availability and advances in spatio-temporal analysis. However, the following gaps still need to be filled: 1) methods to characterise drought that explicitly consider its spatio-temporal features, such as spatial extent (area) and pathway; 2) methods to monitor and predict drought that include...

Crop yield is one of the variables used to assess the impact of droughts on agriculture. Crop growth models calculate yield and variables related to plant development and become more suitable for crop yield estimation. However, these models are limited in that specific data are needed for computation. Given this limitation, machine learning (ML) mo...

Studies of drought have increased in light of new data availability and advances in spatio-temporal analysis. However, the following gaps still need to be filled: 1) methods to characterise drought that explicitly consider its spatio-temporal features, such as spatial extent (area) and pathway; 2) methods to monitor and predict drought that include...

Final version via TU Delft, copy and paste link into your browser:[https://research.tudelft.nl/files/181226651/THREEDIMENSIONAL_CLUSTERING_IN_THE_CHARACTERIZATION_OF_SPATIOTEMPORAL.pdf] Abstract: In its three-dimensional (3-D) characterization, drought is an event whose spatial extent changes over time. Each drought event has an onset and end time,...

Final version via TU Delft, copy and paste link into your browser:[https://research.tudelft.nl/files/181226651/THREEDIMENSIONAL_CLUSTERING_IN_THE_CHARACTERIZATION_OF_SPATIOTEMPORAL.pdf] Abstract: In its three-dimensional (3-D) characterization, drought is an event whose spatial extent changes over time. Each drought event has an onset and end time,...

As recommended by Water Resources Research (WRR) journal, the preprint of our paper, is now available on the Earth and Space Science Open Archive (ESSOAr). In collaboration with Dr. Gerald Corzo Perez, Vitali Díaz Mercado, and Dr. Milad Aminzadeh, we have introduced a new drought index "Wet-environment Evapotranspiration and Precipitation Standar...

Drought characterization and risk assessment are of great significance due to drought’s negative impact on human health, economy, and ecosystem. This paper investigates drought characterization and risk assessment in the Lempa River basin in Central America. We applied the Standardized Evapotranspiration Deficit Index (SEDI) for drought characteriz...

Precipitation data are useful for the management of water resources as well as flood and drought events. However, precipitation monitoring is sparse and often unreliable in regions with complicated geomorphology. Subsequently, the spatial variability of the precipitation distribution is frequently represented incorrectly. Satellite precipitation da...

The spatiotemporal monitoring of droughts is a complex task. In the past decades, drought monitoring has been increasingly developed, while the consideration of its spatio-temporal dynamics is still a challenge. This study proposes a method to build the spatial tracks and paths of drought, which can enhance its monitoring. The steps for the drought...

Open access via TUDelft repository (https://repository.tudelft.nl/islandora/object/uuid:4acce8f6-ebd4-454f-ad06-9daac5e35637/datastream/OBJ/download) Drought is a complex natural phenomenon. The description of the way in which drought changes (moves) in space may help to acquire knowledge on its drivers and processes to improve its monitoring and...

PDF via TUDelft repository [https://pure.tudelft.nl/ws/portalfiles/portal/117825973/3_s2.0_B9780128116890000070_main.pdf] Drought indicators are of critical importance in characterization and forecasting. The use of the Standardized Precipitation Index (SPI) has increasingly become the main tool for drought analysis; however, the index lacks hydrol...

PDF via TUDelft repository [https://pure.tudelft.nl/ws/portalfiles/portal/116645602/3_s2.0_B9780128116890000033_main.pdf] Abstract: Extreme hydrological events (EHEs), such as droughts and floods, vary spatially and temporally in nature. The increase in the number of events in the last few decades has motivated the research of the spatiotemporal...

PDF via TUDelft repository [https://pure.tudelft.nl/ws/portalfiles/portal/117826537/3_s2.0_B9780128116890000045_main.pdf] Abstract: Understanding, characterizing, and predicting drought is vital for the reduction of its consequences. In the last few decades, many studies have moved drought analysis from the conventional lumped approach to a more sp...

This study highlights the advantage of satellite-derived rainfall products for hydrological modeling in regions of insufficient ground observations such as West African basins. Rainfall is the main input for hydrological models; however, gauge data are scarce or difficult to obtain. Fortunately, several precipitation products are available. In this...

Distributed hydrological simulations aid to investigate the spatio-temporal behaviour of hydrological variables. However, data to feed hydrological models are not always available mainly due to lack of gauges or high retrieval fees. In this research, two 0.25- degree daily precipitation databases from the Tropical Rainfall Measuring Mission (TRMM)...

Due to the underlying characteristics of drought, monitoring of its spatio-temporal development is difficult. Last decades, drought monitoring have been increasingly developed, however, including its spatio-temporal dynamics is still a challenge. This study proposes a method to monitor drought by tracking its spatial extent. A methodology to build...

Given the difficulty to access gauge data, satellite-based rainfall is available for use in hydrological modelling. We investigate the performance of PERSIANN-CDR over the Bani River Basin (Upper Niger and four sub basins of the Upper Senegal River. PERSIANN-CDR data was compared with rain gauges of 11 synoptic stations. In addition, CEQUEAU distri...

Currently, large-scale drought monitoring is carried out through the implementation of different drought indicators that use both remote sensing and ground-based data. Among the most promising are those that use remote sensing data variables, principally soil moisture (SM) and evaporation (E), because of their link with agricultural drought impacts...

This tool performs the Non-Contiguous Drought Analysis (NCDA) proposed by Corzo Perez et al. (2011 HESS), on a monthly basis. Furthermore, it computes drought characteristics (i.e., Duration, Severity and Intensity=D/S) from one arrangement (rows x cols x time) containing drought indicator values. The latest update of the STAND toolbox can be obta...

Big data is a growing area of science where hydroinformatics can benefit largely. There have been a number of important developments in the area of data science aimed at analysis of large datasets. Such datasets related to water include measurements, simulations, reanalysis, scenario analyses and proxies. By convention, information contained in the...

Hydrological studies need an essential forward movement in the area of spatiotemporal modelling and data analysis. During the last years, there has been a significant increase in global spatial data available from different sources. This considerable amount of data is creating the need for a change in how to approach the spatiotemporal analyses of...

Droughts are becoming more intense and severe, causing more deaths than other hazards in the past century. Therefore, to face up drought impacts with the optimal strategies, it is necessary a better understand of the drought phenomenon. There are hydrological studies that investigate the processes that govern the genesis and development of the drou...

In the context of the water-related SDGs, goal 11.5 is proposed to reduce the number of deaths and the number of affected people by water-related disasters (WRD). In this regard, one of the main challenges in the implementation agenda of SDGs is to have tools, data, and indicators that help to achieve the goals mentioned. In this subject, the prese...

Note: Before downloading, please check the latest update at https://github.com/hydroinfo4x/STAND-LS. STAND_LS_NCDA.m performs the Non-Contiguous Drought Analysis (NCDA) proposed by Corzo et al. (2011 HESS), on a monthly basis. Furthermore, it computes drought characteristics (i.e., Duration, Severity and Intensity=D/S) from one arrangement (rows x...

Please check the latest update at https://github.com/hydroinfo4x/STAND-LS.

Note: Before downloading, please check the latest update at https://github.com/hydroinfo4x/STAND-LS. STAND_LS_NCDA.m performs the Non-Contiguous Drought Analysis (NCDA) proposed by Corzo et al. (2011 HESS), on a monthly basis. Furthermore, it computes drought characteristics (i.e., Duration, Severity and Intensity=D/S) from one arrangement (rows x...

This presentation shows some results of the application of STAND_LS_NCDA.m. The latest update of the STAND toolbox can be obtained at https://github.com/hydroinfo4x/STAND-LS.

p>Lately, drought is more intense and much more severe around the globe, causing more deaths than other hazards in the past century. Drought can be characterized quantitatively for its spatial extent, intensity and duration by using drought indicators. Several indicators have been developed in order to characterize drought, being the most widesprea...

Hydrological modeling is an essential tool to evaluate water resources in hydrological basins. The time invested in it depends on the structure of the hydrological model chosen, the amount and quality of information required and the efforts invested in calibration. CEQUEAU is a distributed hydrological model developed at the INRS-ETE, Quebec, Canad...

This document shows the application of a satellite-based rainfall estimator, the Hydroestimator (HE) system, developed by the Engineering Institute of the National Autonomous University of Mexico (II-UNAM), within the framework of the Comprehensive Water Plan of Tabasco. The HE system was applied to calculate rainfall in four sub-basins of the La S...

Se muestra la aplicación de un sistema Hidroestimador (HE) desarrollado por el Instituto de Ingeniería de la Universidad Nacional Autónoma de México (II-UNAM), dentro del marco del Plan Hídrico Integral de Tabasco. El sistema HE se aplicó para el cálculo de las láminas de lluvia en cuatro subcuencas del río La Sierra (Tabasco, México), las cuales s...

In the state of Sonora, the growth of Hermosillo City and the intense agricultural activity in the lower basin plains pose a conflict of overexploitation of surface and groundwater sources. This situation implies a growing demand for water volumes that can hardly be met with the current water resources provided by the Sonora River basin. Given this...

En este trabajo se presenta el análisis de recarga vertical en el Acuífero del Valle de Toluca, donde el objetivo de esta investigación fue estimar la recarga vertical debida a precipitación, tomando en cuenta las características topográficas, climatológicas, de tipo y uso de suelo; también se evaluó la contribución de origen antrópico y las de los...

Hydrological modelling is an essential tool for water resources assessment in basins. The time required for this purpose depends on the chosen hydrological model's structure, the input information's quantity and quality, and the efforts invested in calibrating the hydrological model. The CEQUEAU model is a distributed parameter hydrological model i...

This BSc thesis is an outcome of the project "Evaluation of the Vibration Limit State of a Vehicular Bridge in Mexico State Based on Reliability Analysis" UAEM261/2006U, developed at the Faculty of Engineering of the Autonomous University of Mexico State. The study's selection was due to reports from the authorities responsible for its construction...