MODELISATRION DE L'ALLUMAGE EN MILIEU TURBULENT AVEC CHIMIE COMPLEXE

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ISBN 13 :
Total Pages : 185 pages
Book Rating : 4.:/5 (49 download)

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Book Synopsis MODELISATRION DE L'ALLUMAGE EN MILIEU TURBULENT AVEC CHIMIE COMPLEXE by : Stéphane Vincent (Ingénieur projet).)

Download or read book MODELISATRION DE L'ALLUMAGE EN MILIEU TURBULENT AVEC CHIMIE COMPLEXE written by Stéphane Vincent (Ingénieur projet).) and published by . This book was released on 1997 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: CE TRAVAIL CONCERNE L'ETUDE PAR SIMULATION NUMERIQUE DE L'INTERACTION QUI EXISTE ENTRE LES PHENOMENES TURBULENTS ET LES PHENOMENES CHIMIQUES AYANT LIEU EN COMBUSTION ET EN PARTICULIER DURANT LES PREMIERS INSTANTS DE CELLE-CI. LE CAS GENERAL EST CELUI DES GAZ PARFAITEMENT PREMELANGES. CETTE ETUDE SE FAIT PAR UNE APPROCHE BASEE SUR LES FONCTIONS DE DENSITE DE PROBABILITE (PDF) COUPLEE A DES CINETIQUES CHIMIQUES COMPLEXES. CETTE ETUDE A ETE EFFECTUEE DANS DEUX SITUATIONS DISTINCTES. DANS UN PREMIER TEMPS L'ETUDE EST EFFECTUEE LORSQUE LA COMBUSTION A LIEU PAR AUTO-INFLAMMATION DANS MELANGE D'HYDROGENE ET D'AIR A PERMIS LA MISE EN EVIDENCE, AVEC UNE METHODE RELATIVEMENT SIMPLE A METTRE EN UVRE, DES RELATIONS FORTES ENTRE LES DIFFERENTES ESPECES CHIMIQUES EN COURS DE COMBUSTION. ENSUITE CETTE ETUDE A ETE EFFECTUEE DANS LE CAS DE L'ALLUMAGE PAR ETINCELLE DE MELANGES HYDROGENE-AIR ET HEPTANE-AIR EN UTILISANT UN MODELE D'ALLUMAGE OU L'ETINCELLE EST REPRESENTEE PAR UN DEPOT D'ENERGIE DE DUREE FINIE ET DANS UN VOLUME FINI. LE COUPLAGE DE CE MODELE D'ALLUMAGE AVEC UNE CINETIQUE CHIMIQUE DETAILLEE A PERMIS LA PREDICTION DE LIMITE D'INFLAMMATION. LE MEMOIRE PRESENTE D'ABORD DES RAPPELS DE LA THEORIE DE LA COMBUSTION TURBULENTE, DIFFERENTS TYPES DE MODELISATION ET, EN PARTICULIER, L'APPROCHE DE LA PDF. PUIS UNE REVUE CRITIQUE DE MODELES D'ALLUMAGE PAR ETINCELLE EST EFFECTUEE ET LE MODELE UTILISE EST PRESENTE. UNE DESCRIPTION DES METHODES DE REDUCTIONS DES SCHEMAS NUMERIQUES EST PROPOSEE AINSI QUE LE CHOIX DES CINETIQUES CHIMIQUES UTILISEES. UNE ETUDE DE L'AUTO-ALLUMAGE TURBULENT DE MELANGE D'HYDROGENE-AIR EST ALORS EFFECTUEE ET DANS LA DERNIERE PARTIE L'ETUDE DE L'ALLUMAGE TURBULENT PAR ETINCELLE EST EFFECTUE.

L'ALLUMAGE DANS LES MOTEURS A ESSENCE. UNE MODELISATION ET DES APPLICATIONS

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ISBN 13 :
Total Pages : 200 pages
Book Rating : 4.:/5 (49 download)

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Book Synopsis L'ALLUMAGE DANS LES MOTEURS A ESSENCE. UNE MODELISATION ET DES APPLICATIONS by : Nicolas Fruchard

Download or read book L'ALLUMAGE DANS LES MOTEURS A ESSENCE. UNE MODELISATION ET DES APPLICATIONS written by Nicolas Fruchard and published by . This book was released on 1995 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: CE TRAVAIL PRESENTE UN MODELE D'ALLUMAGE D'UN MILIEU TURBULENT DANS LEQUEL LE CARBURANT ET L'AIR SONT PREALABLEMENT PARFAITEMENT MELANGES. LES CONDITIONS INITIALES RETENUES SONT PROCHES DE CELLES RENCONTREES DANS LES MOTEURS A ALLUMAGE COMMANDE. LE TEMPS CARACTERISTIQUE DE LA TURBULENCE ET LA DUREE DE L'ALLUMAGE AINSI QUE L'ECHELLE DE LA TURBULENCE ET L'ESPACE ENTRE LES ELECTRODES SONT SENSIBLEMENT DU MEME ORDRE DE GRANDEUR. IL Y AURA ALORS DE FORTES INTERACTIONS ENTRE LA TURBULENCE, LA CHIMIE ET L'APPORT D'ENERGIE. ELLES SERONT ETUDIEES PAR UNE APPROCHE BASEE SUR LES FONCTIONS DE DENSITE DE PROBABILITE (PDF). L'EQUATION D'EVOLUTION DE LA PDF DES VARIABLES THERMOCHIMIQUES, CONCENTRATION ET ENTHALPIE, EST RESOLUE PAR UNE METHODE DE MONTE-CARLO. TOUT D'ABORD QUELQUES RAPPELS GENERAUX SUR L'ALLUMAGE ET LA FORMATION DE LA FLAMME, L'AEROTHERMOCHIMIE ET L'APPROCHE FONCTION DE DENSITE DE PROBABILITE SONT EXPOSES. LE MEMOIRE PRESENTE ENSUITE UN MODELE D'ALLUMAGE ET SON COMPORTEMENT VIS-A-VIS DES VARIATIONS DE TURBULENCE, DE CONDITIONS THERMODYNAMIQUES INITIALES ET D'ENERGIE FOURNIE AU MELANGE. UN COUPLAGE DE CE MODELE A UN CODE DE CALCUL UTILISE POUR LES SIMULATIONS DE L'AERODYNAMIQUE INTERNE ET DE LA COMBUSTION DANS LES MOTEURS A ALLUMAGE COMMANDE CONSTITUE UN DES BUTS DE CE TRAVAIL. IL EST DONC EXPOSE, AINSI QU'UNE PREMIERE APPLICATION DANS UNE BOMBE A VOLUME CONSTANT DANS LAQUELLE REGNE UNE TURBULENCE HOMOGENE ET ISOTROPE. LES APPLICATIONS A UN MONOCYLINDRE NECESSITENT TOUT D'ABORD DES DONNEES EXPERIMENTALES COMPLEMENTAIRES, TELLES QUE DES MESURES DE TURBULENCE AU VOISINAGE DE LA BOUGIE ET DES MESURES D'ENERGIE D'ALLUMAGE. UNE FOIS CES MESURES REALISEES, DES CALCULS COMPLETS SUR PLUSIEURS POINTS DE FONCTIONNEMENT DU MOTEUR SONT EXPOSES.

Etude de l'allumage et de la structure des flammes turbulentes

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ISBN 13 :
Total Pages : 191 pages
Book Rating : 4.:/5 (49 download)

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Book Synopsis Etude de l'allumage et de la structure des flammes turbulentes by : Markus Baum

Download or read book Etude de l'allumage et de la structure des flammes turbulentes written by Markus Baum and published by . This book was released on 1994 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ce document présente les résultats d'une étude numérique et théorique des flammes prémélangées. Les sujets abordés sont l'allumage des flammes et l'interaction entre front de flamme et turbulence homogène isotrope dans des configurations bidimensionnelles. Un des objectifs poursuivis était d'envisager la faisabilité d'une simulation directe complète d'un écoulement réactif turbulent avec chimie et modèles de transport complets. De façon générale, on constate que cet objectif est aujourd'hui réalisable et on présente ici un certain nombre d'applications. Un algorithme de simulation directe (DNS) a été développé dans le cadre de ce travail pour aborder ces problèmes. L'algorithme, initialement développé pour traiter des schémas cinétiques simplifiés est ensuite étendu aux schémas cinétiques plus détaillés avec des propriétés de transport réalistes (avec l'utilisation de CHEMKIN et TRANSPORT). Cet algorithme a permis tout d'abord d'étudier l'allumage de flammes prémélangées avec un schéma cinétique simple. Nous nous sommes intéressés au mécanisme qui contrôle l'allumage dans des écoulements turbulents. Dans une première approche, nous avons étudié l'allumage par déposition d'énergie dans des écoulements a flux massique imposé en configuration bidimensionnelle. Les délais et les temps minimaux d'allumage sont déterminés en fonction de la puissance de chauffage et du flux. Les rayons critiques des noyaux de flamme sont aussi examinés. Un modèle simple est enfin présenté pour représenter ces résultats. Dans une seconde étude nous avons considéré l'interaction entre front de flamme et turbulence homogène isotrope dans une configuration bidimensionnelle. Cette étude est réalisée pour des flammes hydrogène-air représentées par un schéma cinétique a 9 espèces et 19 réactions. Une flamme plane, stationnaire, laminaire, non-étirée, adiabatique est superposée a un champ de vitesse déterminé sur la base d'un spectre d'énergie du type Von Karmann-Pao. L'observation de l'évolution du front de flamme a permis d'établir une description qualitative ainsi que les propriétés statistiques de ce type de flamme.

Satellite Situation Report

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ISBN 13 :
Total Pages : 366 pages
Book Rating : 4.:/5 (319 download)

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Book Synopsis Satellite Situation Report by : Goddard Space Flight Center. Office of Public Affairs

Download or read book Satellite Situation Report written by Goddard Space Flight Center. Office of Public Affairs and published by . This book was released on 1977 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:

An Introduction to Differential Manifolds

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Publisher : Springer
ISBN 13 : 3319207350
Total Pages : 408 pages
Book Rating : 4.3/5 (192 download)

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Book Synopsis An Introduction to Differential Manifolds by : Jacques Lafontaine

Download or read book An Introduction to Differential Manifolds written by Jacques Lafontaine and published by Springer. This book was released on 2015-07-29 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an introduction to differential manifolds. It gives solid preliminaries for more advanced topics: Riemannian manifolds, differential topology, Lie theory. It presupposes little background: the reader is only expected to master basic differential calculus, and a little point-set topology. The book covers the main topics of differential geometry: manifolds, tangent space, vector fields, differential forms, Lie groups, and a few more sophisticated topics such as de Rham cohomology, degree theory and the Gauss-Bonnet theorem for surfaces. Its ambition is to give solid foundations. In particular, the introduction of “abstract” notions such as manifolds or differential forms is motivated via questions and examples from mathematics or theoretical physics. More than 150 exercises, some of them easy and classical, some others more sophisticated, will help the beginner as well as the more expert reader. Solutions are provided for most of them. The book should be of interest to various readers: undergraduate and graduate students for a first contact to differential manifolds, mathematicians from other fields and physicists who wish to acquire some feeling about this beautiful theory. The original French text Introduction aux variétés différentielles has been a best-seller in its category in France for many years. Jacques Lafontaine was successively assistant Professor at Paris Diderot University and Professor at the University of Montpellier, where he is presently emeritus. His main research interests are Riemannian and pseudo-Riemannian geometry, including some aspects of mathematical relativity. Besides his personal research articles, he was involved in several textbooks and research monographs.

Aeronomy

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Publisher : Elsevier
ISBN 13 : 1483260666
Total Pages : 445 pages
Book Rating : 4.4/5 (832 download)

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Book Synopsis Aeronomy by : P. M. Banks

Download or read book Aeronomy written by P. M. Banks and published by Elsevier. This book was released on 2013-09-24 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aeronomy, Part A is an attempt to make a comprehensive exposition of the processes in aeronomy, the study of composition, movement, and thermal balance of the upper regions of the planetary atmosphere. The text covers topics such as atmospheric regions and atmospheric density, the temperature and molecular mass of the atmosphere; the permanent constituents and the molecular and isotonic composition of the homosphere; and the transition from the homosphere to the heterosphere. Also covered are topics such as the temperature gradient and energies in the thermosphere, conditions at 200km and above 250km, solar radiation and ionization, and aeronomic reactions. The book is recommended for scientists, especially natural physicists, who would like to know more about the field of aeronomy and its advances.

Combustion and Flames

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Publisher : Editions Technips
ISBN 13 : 9782710807407
Total Pages : 0 pages
Book Rating : 4.8/5 (74 download)

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Book Synopsis Combustion and Flames by : Roland Borghi

Download or read book Combustion and Flames written by Roland Borghi and published by Editions Technips. This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Professionals working in the field of combustion may well find many points of interest, highlighted by the book's logical and global approach to phenomena, which considers mechanical, thermal and chemical aspects simultaneously. The book prioritises an understanding of the physical and chemical aspects of the phenomena, and lays particular emphasis on experimental analyses and modern numerical simulations, and on the way in which these phenomena are translated into equations.Contents: Introduction: Discovering combustion and flames. 1. Combustion thermodynamics. 2. Chemical kinetics applied to combustion. 3. Mass and energy transport by convection and diffusion. 4. Self-ignitions in closed systems. 5. Laminar flames and deflagrations. 6. Turbulent flames and deflagrations. 7. Detonation and supersonic combustion. 8. Flame ignition. 9. Combustion of liquids and sprays. 10. Pollutant emissions in combustion reactions. Index.

Minimum competence in scientific English

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Publisher : L'Editeur : EDP Sciences
ISBN 13 : 9782868835888
Total Pages : 264 pages
Book Rating : 4.8/5 (358 download)

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Book Synopsis Minimum competence in scientific English by : Sue Blattes

Download or read book Minimum competence in scientific English written by Sue Blattes and published by L'Editeur : EDP Sciences. This book was released on 2003 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cet ouvrage, devenu célèbre sous son sigle MCSE, a déjà été utilisé par plus de 50 000 étudiants, chercheurs, professionnels. L'objectif est de lire et écrire des textes en anglais scientifique avec facilité et pertinence. L'ouvrage est conçu pour que l'apprenant devienne un véritable utilisateur de l'anglais. La méthode originale repose sur l'analyse des fonctions et structures nécessaires : measurement, frequency, comparison, modification, link words, time, cause and consequence, hypothesis, modality, purpose and process, impersonal forms, compound nouns and adjectives. Dans chaque unit, des tests d'auto-évaluation permettent de se situer et de construire son parcours de formation, d'abord en définissant ses objectifs à l'aide des key points et du lexis, puis, de façon plus personnalisée, en puisant dans les examples in context, checkpoints (back to basics, word web), web search, FAQs... MCSE est l'outil de base d'une méthode qui comprend aussi d'autres outils dans la même collection (Listening Comprehension for Scientiflc English et Speaking Skills in Scientitic English). L'ouvrage est destiné à tout apprenant de niveau baccalauréat qui désire acquérir une réelle compétence dans l'écriture et la lecture de textes en anglais scientifique.

Popular Astronomy

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ISBN 13 :
Total Pages : 732 pages
Book Rating : 4.A/5 ( download)

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Book Synopsis Popular Astronomy by : Camille Flammarion

Download or read book Popular Astronomy written by Camille Flammarion and published by . This book was released on 1894 with total page 732 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Space Debris

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Publisher : Springer Science & Business Media
ISBN 13 : 3540376747
Total Pages : 438 pages
Book Rating : 4.5/5 (43 download)

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Book Synopsis Space Debris by : Heiner Klinkrad

Download or read book Space Debris written by Heiner Klinkrad and published by Springer Science & Business Media. This book was released on 2006-09-01 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: The future evolution of the debris environment will be forecast on the basis of traffic models and possible hazard mitigation practices. The text shows how large trackable objects will have re-entry pinpointed and predictions made on related risk assessment for possible ground impact. Models will also be described for meteoroids which are also a prevailing risk.

Radioactive Aerosols

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Publisher : Elsevier
ISBN 13 : 0080555985
Total Pages : 187 pages
Book Rating : 4.0/5 (85 download)

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Book Synopsis Radioactive Aerosols by : Constantin Papastefanou

Download or read book Radioactive Aerosols written by Constantin Papastefanou and published by Elsevier. This book was released on 2011-07-28 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt: Whenever radioactivity is released to the atmosphere, for example by the detonation of nuclear weapons or the testing of nuclear weapons or from nuclear reactor accidents that fraction of it which remains airborne for more than a few hours is liable to be attached to aerosol particles. The resulting radioactive aerosols are carried by atmospheric mixing processes until they settle out or are scavenged by precipitation. The radiation exposure pathway of maximum concern to humans is by inhalation of aerosols and their deposition in the respiratory tract. In this context, it is important to note that radioactive aerosols are commonly of natural origin alos. In particular, the associated radionuclides can be of natural terrestrial origin, such as the decay products of radon gas, or they can e cosmogenic, such as beryllium-7. The exposure of miners of uranium and other ores and minerals to radon and its aerosol-borne decay products is of major significance. The book describes the formation of aerosols, their aerodynamic size distribution, their atmospheric residence time, their sampling and measurement, the range of radioactive aerosols found and studied thus far, including man-made nuclides and radon decay products and their interaction with man, including deposition in the lung and subsequent health effects. Advanced level science handbook for researchers, scientists and academics Covers all aspects of radiation exposure in humans, including subsequent health implications Presents the latest findings and analysis in this highly topical area

Biological Dosimetry

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Publisher : Springer Science & Business Media
ISBN 13 : 3642693342
Total Pages : 343 pages
Book Rating : 4.6/5 (426 download)

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Book Synopsis Biological Dosimetry by : W. G. Eisert

Download or read book Biological Dosimetry written by W. G. Eisert and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: In October 1982, a small international symposium was held at the Gesellschaft fUr Strahlen- und Umweltforschung mbH (GSF) in Munich as a satellite meeting of the IX International Conference on Analytical Cytology. The symposium focussed on cytometric approaches to biological dosimetry, and was, to the best of our knowledge, the first meeting on this subject ever held. There was strong encouragement from the 75 attendees and from others to publish a proceedings of the symposium. Hence this book, containing 30 of the 36 presentations, has been assembled. Dosimetry, the accurate and systematic determination of doses, usually refers to grams of substance administered or rads of ionization or some such measure of exposure of a patient, a victim or an experimental system. The term also can be used to describe the quantity of an ultimate, active agent as delivered to the appropriate target material within a biological system. Thus, for mutagens, one can speak of DNA dosimetry, meaning the number of adducts produced in the DNA of target cells such as bone-mar row stem cells or spermatogonia.

Radiation Protection Activities

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ISBN 13 :
Total Pages : 200 pages
Book Rating : 4.E/5 ( download)

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Book Synopsis Radiation Protection Activities by : United States. Environmental Protection Agency. Office of Radiation Programs

Download or read book Radiation Protection Activities written by United States. Environmental Protection Agency. Office of Radiation Programs and published by . This book was released on 1976 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Operational Radiation Safety Program

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Publisher :
ISBN 13 : 9780929600598
Total Pages : 0 pages
Book Rating : 4.6/5 (5 download)

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Book Synopsis Operational Radiation Safety Program by : National Council on Radiation Protection and Measurements

Download or read book Operational Radiation Safety Program written by National Council on Radiation Protection and Measurements and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Ionizing Radiation, Part 2

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Publisher :
ISBN 13 :
Total Pages : 620 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Ionizing Radiation, Part 2 by : IARC Working Group on the Evaluation of Carcinogenic Risks to Humans

Download or read book Ionizing Radiation, Part 2 written by IARC Working Group on the Evaluation of Carcinogenic Risks to Humans and published by . This book was released on 2001 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evaluates the evidence for carcinogenicity of ionizing radiation from internally deposited radionuclides. The radionuclides considered belong to two broad categories, those that emit a-particles (helium nuclei) and those that emit b-particles (electrons).

Health Protection

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Publisher : Oxford University Press
ISBN 13 : 0198745478
Total Pages : 481 pages
Book Rating : 4.1/5 (987 download)

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Book Synopsis Health Protection by : Samuel Ghebrehewet

Download or read book Health Protection written by Samuel Ghebrehewet and published by Oxford University Press. This book was released on 2016 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Health Protection: Principles and practice is a practical guide for practitioners working at all levels in public health and health protection, including those with a non-specialist background. It is the first textbook in health protection to address all three domains within the field (communicable disease control; emergency preparedness, resilience and response (EPRR); and environmental public health) in a comprehensive and integrated manner. Written by leading practitioners in the field, the book is rooted in a practice-led, all-hazards approach, which allows for easy real-world application of the topics discussed. The chapters are arranged in six sections, which begin with an in-depth introduction to the principles of health protection and go on to illuminate the three key elements of the field by providing: case studies and scenarios to describe common and important issues in the practice of health protection; health protection tools, which span epidemiology and statistics, infection control, immunisation, disease surveillance, and audit and service improvement; and evidence about new and emerging health protection issues. It includes more than 100 health protection checklists (SIMCARDs), covering infections from anthrax to yellow fever, non-infectious diseases emergencies and environmental hazards. Written from first-hand experience of managing communicable diseases these provide practical, stand-alone quick reference guides for in-practice use. Both the topical content of Health Protection: Principles and practice, and the clearly described health protection principles the book provides, makes it a highly relevant resource for wider public health and health protection professionals in this continually evolving field.

Whole Body Counters

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Publisher :
ISBN 13 :
Total Pages : 40 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Whole Body Counters by : John H. Woodburn

Download or read book Whole Body Counters written by John H. Woodburn and published by . This book was released on 1964 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: