The two-volume set LNCS 11973 and 11974 constitute revised selected papers from the Third International Conference on Numerical Computations: Theory and Algorithms, NUMTA 2019, held in Crotone, Italy, in June 2019. This volume, LNCS 11973, consists of 34 full and 18 short papers chosen among papers presented at special streams and sessions of the Conference. The papers in part I were organized following the topics of these special sessions: approximation: methods, algorithms, and applications; computational methods for data analysis; first order methods in optimization: theory and applications; high performance computing in modelling and simulation; numbers, algorithms, and applications; optimization and management of water supply.

Inhalt
Approximation: Methods, Algorithms, and Applications.- Towards an Efficient Implementation of an Accurate SPH Method.- A Procedure for Laplace Transform Inversion Based on Smoothing Exponential-Polynomial.- Splines.- An Adaptive Refinement Scheme for Radial Basis Function Collocation.- A 3D efficient Procedure for Shepard Interpolants on Tetrahedra.- Interpolation by Bivariate Quadratic Polynomials and Applications to the Scattered Data Interpolation Problem.- Comparison of Shepard's Like Methods with Different Basis Functions.- A New Remez-type Algorithm for Best Polynomial Approximation.- An SVE Approach for the Numerical Solution of Ordinary Differential Equations.- Uniform Weighted Approximation by Multivariate Filtered Polynomials.- Computational Methods for Data Analysis.- A Travelling Wave Solution for Nonlinear Colloid Facilitated Mass Transport in Porous Media.- Performance Analysis of a Multicore Implementation for Solving a Two-dimensional Inverse Anomalous Diffusion Problem.- Adaptive RBF Interpolation for Estimating Missing Values in Geographical Data.- Stochastic Mechanisms of Information Flow in Phosphate Economy of Escherichia Coli.- NMR Data Analysis of Water Mobility in Wheat Flour Dough: A Computational Approach.- First Order Methods in Optimization: Theory and Applications.- A Limited Memory Gradient Projection Method for Box-Constrained Quadratic Optimization.- Problems.- A Gradient-Based Globalization Strategy for the Newton Method.- On the Steplength Selection in Stochastic Gradient Methods.- Efficient Block Coordinate Methods for Blind Cauchy Denoising.- High Performance Computing in Modelling and Simulation.- A Parallel Software Platform for Pathway Enrichment.- Hierarchical Clustering of Spatial Urban Data.- Improving Efficiency in Parallel Computing Leveraging Local Synchronization.- A General Computational Formalism for Networks of Structured Grids.- Preliminary Model of Saturated.- Flow Using Cellular Automata.- A Cybersecurity Framework for Classifying Non Stationary Data Streams Exploiting Genetic Programming and Ensemble Learning.- A Dynamic Load Balancing Technique for Parallel Execution of Structured Grid Models.- Final Sediment Outcome from Meteorological Flood Events: A Multi-Modelling Approach.- Parallel Algorithms for Multifractal Analysis of River Networks.- A Methodology Approach to Compare Performance of Parallel Programming Models for.- Shared-Memory Architectures.- Numbers, Algorithms, and Applications.- New Approaches to Basic Calculus: An Experimentation via Numerical Computation.- A Multi-factor RSA-like Scheme with Fast Decryption Based on Rédei Rational Functions over the Pell Hyperbola.- Paradoxes of the Infinite and Ontological Dilemmas between Ancient Philosophy and Modern Mathematical Solutions.- The Sequence of Carboncettus Octagons.- On the Arithmetic of Knuth's Powers and Some Computational Results about Their Density.- Combinatorics on n-sets: Arithmetic Properties and Numerical Results.- Numerical Problems in XBRL Reports and the Use of Blockchain as Trust Enabler.- Modelling on Human Intelligence a Machine Learning System.- Algorithms for Jewelry Industry 4.0.- Clustering Analysis to Profile Customers' Behaviour in POWER CLOUD Energy Community.- A Grossone-based Numerical Model for Computations with Infinity: A Case Study in an Italian High School.- A Computational Approach with MATLAB Software for Nonlinear Equation Roots Finding in High School Maths.- Task Mathematical Modelling Design in a Dynamic Geometry Environment: Archimedean Spiral's Algorithm.- Optimization and Management of Water Supply.- Numerical Experimentations for a New Set of Local Indices of a Water Network.- Performance Management of Demand and Pressure Driven Analysis in a Monitored Water.- Distribution Network.- Algebraic Tools and New Local Indices for Water Networks: Some Numerical Examples.- Identification of Contamination Potential Source (ICPS): A Topological Approach for the Optimal.- Recognition of Sensitive Nodes in a Water Distribution Network.- Seeking for a Trade-off between Accuracy and Timeliness in Meteo-hydrological Modeling Chains.- Optimization Model for Water Distribution Network Planning in a Realistic Orographic Framework.- Scenario Optimization of Complex Water Supply Systems for Energy Saving and Drought-risk Management.- Optimizing Rainwater Harvesting Systems for Non-potable Water Uses and Surface Runoff Mitigation.- New Mathematical Optimization Approaches for LID Systems.- Evaluation of an Integrated Seasonal Forecast System for Agricultural Water Management in Mediterranean Regions.- Optimization of Submarine Outfalls with a Multiport Diffuser Design.