The Einstein Toolkit: A Community Computational Infrastructure for Relativistic Astrophysics

We describe the Einstein Toolkit, a community-driven, freely accessible computational infrastructure intended for use in numerical relativity, relativistic astrophysics, and other applications. The Toolkit, developed by a collaboration involving researchers from multiple institutions around the world, combines a core set of components needed to simulate astrophysical objects such as black holes, compact objects, and collapsing stars, as well as a full suite of analysis tools. The Einstein Toolkit is currently based on the Cactus Framework for high-performance computing and the Carpet adaptive mesh refinement driver. It implements spacetime evolution via the BSSN evolution system and general-relativistic hydrodynamics in a finite-volume discretization. The toolkit is under continuous development and contains many new code components that have been publicly released for the first time and are described in this article. We discuss the motivation behind the release of the toolkit, the philosophy underlying its development, and the goals of the project. A summary of the implemented numerical techniques is included, as are results of numerical test covering a variety of sample astrophysical problems.Comment: 62 pages, 20 figure

Elements of Ion Linear Accelerators, Calm in The Resonances, Other_Tales

The main part of this book, Elements of Linear Accelerators, outlines in Part 1 a framework for non-relativistic linear accelerator focusing and accelerating channel design, simulation, optimization and analysis where space charge is an important factor. Part 1 is the most important part of the book; grasping the framework is essential to fully understand and appreciate the elements within it, and the myriad application details of the following Parts. The treatment concentrates on all linacs, large or small, intended for high-intensity, very low beam loss, factory-type application. The Radio-Frequency-Quadrupole (RFQ) is especially developed as a representative and the most complicated linac form (from dc to bunched and accelerated beam), extending to practical design of long, high energy linacs, including space charge resonances and beam halo formation, and some challenges for future work. Also a practical method is presented for designing Alternating-Phase- Focused (APF) linacs with long sequences and high energy gain. Full open-source software is available. The following part, Calm in the Resonances and Other Tales, contains eyewitness accounts of nearly 60 years of participation in accelerator technology. (September 2023) The LINACS codes are released at no cost and, as always,with fully open-source coding. (p.2 & Ch 19.10)Comment: 652 pages. Some hundreds of figures - all images, there is no data in the figures. (September 2023) The LINACS codes are released at no cost and, as always,with fully open-source coding. (p.2 & Ch 19.10

The MYRRHA reactor design and the primary heat exchanger (PHX) tube rupture event analysis

Tra tutti i differenti concetti di reattori nucleari proposti nell\u2019ambito della Generation IV, I reattori \u201cpool-type\u201d raffreddati a metallo liquido pesante rappresentano una delle opzioni pi\uf9 promettenti. Uno dei principali obbiettivi, dal punto di vista progettuale e della sicurezza, consiste nell\u2019ottenere un concetto efficiente e compatto. Tale requisito spesso implica l\u2019adozione di un numero inferiore di circuiti refrigeranti rispetto ad altri reattori simili. La rimozione del circuito intermedio pu\uf2 essere ottenuta tramite l\u2019adozione di un fluido secondario che entri direttamente nello scambiatore di calore (o generatore di vapore) situato nel vessel primario. Per quanto concerne il fluido secondario, una scelta comune \ue8 rappresentata dall\u2019acqua in pressione. Uno degli eventi pi\uf9 rilevanti dal punto di vista dell\u2019analisi di sicurezza applicata a reattori di questa tipologia \ue8 rappresentato dall\u2019ingresso accidentale di acqua nel vessel primario, che potrebbe scatenare una serie di conseguenze potenzialmente in grado di mettere a repentaglio la sicurezza del reattore. Lo studio di tale transitorio implica un\u2019analisi multifase dei flussi, caratterizzata da svariate fenomenologie su diverse scale spaziali e temporali. MYRRHA \ue8 un reattore di ricerca pool-type raffreddato da una lega eutettica di piombo e bismuto (LBE). Pur essendo un Accelerator Driven System (ADS), ha la capacit\ue0 di operare in modalit\ue0 critica. La potenza generata nel sistema di raffreddamento primario \ue8 trasferita, tramite lo Scambiatore di Calore Primario (PHX), nel sistema secondario, per il quale l\u2019acqua in pressione \ue8 stata selezionata come refrigerante. Le attivit\ue0 del Ph.D. si focalizzeranno sul progetto del reattore MYRRHA, con particolare riferimento al PHX. L\u2019incidente di rottura di un tubo dello scambiatore stesso (PHXTR), con le conseguenze sugli altri componenti del reattore, sar\ue0 analizzato in una configurazione realistica del reattore tramite specifici modelli di calcolo ed attivit\ue0 sperimentali dedicate. Le analisi teoriche sulle conseguenze del rilascio di una miscela bifase di acqua-vapore nel vessel primario devono essere eseguite in condizioni rappresentative del reattore MYRRHA: questo comporta una fedele modellazione, in termini geometrici e di processo, dello scambiatore e degli altri componenti, al fine di essere in grado di simulare l\u2019evoluzione dell\u2019incidente nel modo migliore possibile. L\u2019impatto sui componenti situati all\u2019interno del vessel ed i carichi meccanici generati dall\u2019incidente di rottura del tubo devono essere valutati in base alle reali condizioni d\u2019impianto, cos\uec come l\u2019incremento di pressione nel vessel e la conseguente apertura del disco di rottura. Numerose campagne sperimentali finalizzate all\u2019analisi della rottura di un tubo dello scambiatore primario sono previste nell\u2019ambito del progetto Europeo FP7-MAXSIMA. Tali esperimenti sono stati concepiti per simulare le condizioni operative del reattore MYRRHA nel migliore dei modi, allo scopo di validare i modelli di calcolo. Tali simulazioni numeriche saranno poi utilizzate per estendere le capacit\ue0 predittive degli esperimenti. Lo scopo finale del Ph.D. consiste dunque nella finalizzazione del progetto dello scambiatore di calore del reattore MYRRHA, rivolgendo particolare attenzione allo studio dell\u2019incidente di rottura di un tubo. La programmazione di specifici strumenti di calcolo \ue8 prevista al fine di essere in grado di simulare tutte le fasi dell\u2019incidente e le potenziali implicazioni per la sicurezza dell\u2019impianto.Among the different nuclear plant concepts proposed in the frame of Generation IV, the pool-type reactors cooled by Heavy Liquid Metal represent one of the most promising options. One of the most important challenges, form the point of view of design and safety, consists in optimizing an efficient and compact design. Such requirements often imply the adoption of a lower number of cooling loops in comparison with similar reactor concepts. The intermediate loop can be eliminated by adopting a secondary fluid entering in a heat exchanger (or steam generator) located in the primary vessel. Pressurized water represents a common choice as secondary cooling fluid. One of the most safety-relevant events for this reactor concept is indeed represented by the accidental water ingress in the primary vessel, which can trigger a series of consequences potentially jeopardizing the reactor safety functions. The study of this transient implies the analysis of multiphase flow, characterized by several phenomena on different time and spatial scales. The MYRRHA reactor is a pool-type Material Testing Accelerator Driven System (ADS), cooled by Lead-Bismuth Eutectic (LBE) with the ability to operate also as a critical reactor. Pressurized water is adopted as secondary coolant, removing the power generated in the primary system through the Primary Heat Exchangers (PHX). The Ph. D. activities should focus on the MYRRHA reactor design and the impact of a PHX Tube Rupture (PHXTR) event on its components: all the analyses foreseen and the experimental campaigns in support of calculations should be aimed at studying the transient in MYRRHA relevant configuration. The theoretical analysis on the consequences following the moisture release into the primary vessel must be performed in MYRRHA-like conditions, assuming the correct dimensions for the PHX and all the related systems and components in order to be able to predict in the best way the PHXTR accident evolution. The impact on the reactor internals and the mechanical loads determined by the pressure wave and potential steam explosion should be evaluated according to the real MYRRHA configuration, as well as the pressure build-up in the reactor cover gas and the consequent reactor cover rupture disk break. The experimental campaign foreseen for MYRRHA PHXTR event, mainly in the framework of EU FP7-MAXSIMA project, have been run in a set of conditions that closely resembles the MYRRHA environment. The purpose is to validate the theoretical models and the numerical simulations towards the experiments in order to obtain suitable calculation tools allowing correct predictions. The final purpose of the Ph.D. activities consists then in fully covering the evolution of the PHXTR accident in the MYRRHA reactor by the use of suitable and validated computational tools, taking thus into account all the evolution phases and predicting the potential implications caused by the event

Introduction to Facial Micro Expressions Analysis Using Color and Depth Images: A Matlab Coding Approach (Second Edition, 2023)

The book attempts to introduce a gentle introduction to the field of Facial Micro Expressions Recognition (FMER) using Color and Depth images, with the aid of MATLAB programming environment. FMER is a subset of image processing and it is a multidisciplinary topic to analysis. So, it requires familiarity with other topics of Artifactual Intelligence (AI) such as machine learning, digital image processing, psychology and more. So, it is a great opportunity to write a book which covers all of these topics for beginner to professional readers in the field of AI and even without having background of AI. Our goal is to provide a standalone introduction in the field of MFER analysis in the form of theorical descriptions for readers with no background in image processing with reproducible Matlab practical examples. Also, we describe any basic definitions for FMER analysis and MATLAB library which is used in the text, that helps final reader to apply the experiments in the real-world applications. We believe that this book is suitable for students, researchers, and professionals alike, who need to develop practical skills, along with a basic understanding of the field. We expect that, after reading this book, the reader feels comfortable with different key stages such as color and depth image processing, color and depth image representation, classification, machine learning, facial micro-expressions recognition, feature extraction and dimensionality reduction. The book attempts to introduce a gentle introduction to the field of Facial Micro Expressions Recognition (FMER) using Color and Depth images, with the aid of MATLAB programming environment.Comment: This is the second edition of the boo

Retail property market performance of cities: an investigation of the relationships between spatial configuration of consumer movement and changes in retail stock and value in Leeds, Newcastle and York

The influence of consumer activities on the performance of retail locations and retail property market in cities can be critical. This is because where and how retail consumers choose to transact influences the locational performance of retail property markets in cities. This study investigates relationships between consumer movement and the performance of retail property markets (RPM) between 2010 and 2017 in York, Leeds and Newcastle. The study adopts the spatial configuration (street segment) analysis technique to compute consumer movement patterns (CMP) on the sampled cities’ layouts using DepthMapX to obtain the CMP variables; specifically, integration, choice and NACH metrics. The RPM data were sourced from valuation summary lists belonging to the VOA dataset and analysed using MS Access and MS Excel to obtain RPM variables, namely, changes in retail rental value and changes in retail stock across locations. The study investigates the spatial and statistical relationships between the CMP and RPM variables of cities at mesoscales and macroscales using QGIS and SPSS tools, respectively. The spatial investigations visualise locational relationships between changes in RPM variables and the spatial accessibility index of the CMP variables. The statistical analyses adopted Spearman-rho coefficients to investigate the rank correlation between the RPM and CMP variables. Further statistical (multiple regression) analysis were undertaken to estimate the locational performance of the RPM (dependent variable) using the CMP (independent variables) across all the estimable city layouts. Findings show that there are significant relationships between changes in retail rental value and all the CMP variables at York mesoscale, Leeds mesoscale and Newcastle macroscale. The results indicate that the relationship between configured consumer movement and changes in retail rental value are influenced by scale and city characteristics. The research is the first to estimate the location performance of commercial property by way of spatial configuration analysis. The research outputs are useful tools for retail property market actors to make locational decisions on investments, occupation, development and the strategic management of urban retail space. The study recommends further studies on the prospects of spatial configuration analysis and other methods in estimating the future performance of the commercial property market for optimum utilisation and the management of urban resources