Software development (1)

SOFTWARE DEVELOPMENT AN OPEN SOURCE APPROACH Chapman & Hall/CRC Innovations in Software Engineering and Software Development Series Editor Richard LeBlanc Chair, Department of Computer Science and Software Engineering, Seattle University Aims and Scope This series covers all aspects of software engineering and software development Books in the series will be innovative reference books, research monographs, and textbooks at the undergraduate and graduate level Coverage will include traditional subject matter, cutting-edge research, and current industry practice, such as agile software development methods and service-oriented architectures We also welcome proposals for books that capture the latest results on the domains and conditions in which practices are most effective Published Titles Software Development: An Open Source Approach Allen Tucker, Ralph Morelli, and Chamindra de Silva Forthcoming Titles Fundamentals of Dependable Computing for Software Engineers John Knight Software Metrics, Second Edition Norman Fenton and James Bieman Designing Software André van der Hoek, Alex Baker, and Emily Navarro Systems Engineering Principles for Software Engineers Ray J Madachy Model Based Software Design Adair Dingle Software Engineering: The Current Practice Vaclav Rajlich CHAPMAN & HALL/CRC INNOVATIONS IN SOFTWARE ENGINEERING AND SOFTWARE DEVELOPMENT SOFTWARE DEVELOPMENT AN OPEN SOURCE APPROACH ALLEN TUCKER RALPH MORELLI CHAMINDRA DE SILVA Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an informa business The photo on the cover symbolizes the central themes of free and open source software development: the management of chaos (Raymond’s “bazaar” metaphor), communities, collaboration, openness, teamwork, and agility CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2011 by Taylor and Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S Government works Printed in the United States of America on acid-free paper 10 International Standard Book Number-13: 978-1-4398-1291-4 (Ebook-PDF) This book contains information obtained from authentic and highly regarded sources Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint Except as permitted under U.S Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers For permission to photocopy or use material electronically from this work, please access www.copyright.com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400 CCC is a not-for-profit organization that provides licenses and registration for a variety of users For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com Contents ▲✐st ♦❢ ❋✐❣✉r❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ①✐ ▲✐st ♦❢ ❚❛❜❧❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ①✈ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ①✈✐✐ Pr❡❢❛❝❡ ❆❝❦♥♦✇❧❡❞❣♠❡♥ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❆✉t❤♦rs ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶ ❖✈❡r✈✐❡✇ ❛♥❞ ▼♦t✐✈❛t✐♦♥ ✶✳✶ ✶✳✷ ✶✳✸ ✶✳✹ ❙♦❢t✇❛r❡ ✶ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❚②♣❡s ♦❢ ❙♦❢t✇❛r❡ ✶✳✶✳✷ ❚❤❡ ❈❤❛♥❣✐♥❣ ▲❛♥❞s❝❛♣❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺ ✶✳✶✳✸ ❲❤♦ ❆r❡ t❤❡ ❉❡✈❡❧♦♣❡rs❄ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼ ✶✳✶✳✹ ❙tr❛t❡❣✐❝ ❈❤♦✐❝❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❋r❡❡ ❛♥❞ ❖♣❡♥ ❙♦✉r❝❡ ❙♦❢t✇❛r❡ ✭❋❖❙❙✮ ✷✳✷ ✷✳✸ ✷✳✹ ✷ ✽ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✷ ✶✳✷✳✶ ❖r✐❣✐♥s ❛♥❞ ●r♦✇t❤ ✶✳✷✳✷ ▲✐❝❡♥s✐♥❣ ✶✳✷✳✸ ❲♦r❧❞✇✐❞❡ ■♠♣❛❝t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽ ✶✳✷✳✹ ❍✉♠❛♥✐t❛r✐❛♥ ❋❖❙❙ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✾ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❚✇♦ ❈❛s❡ ❙t✉❞✐❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✳✸✳✶ ❘▼❍ ❍♦♠❡❜❛s❡ ✶✳✸✳✷ ❙❛❤❛♥❛ ❙✉♠♠❛r② ✶✻ ✷✵ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✵ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✵ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✷ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✸ ❲♦r❦✐♥❣ ✇✐t❤ ❛ Pr♦❥❡❝t ❚❡❛♠ ✷✳✶ ✶ ✶✳✶✳✶ ❊①❡r❝✐s❡s ✷ ①①✈ ①①✈✐✐ ✷✼ ❑❡② ❋❖❙❙ ❆❝t✐✈✐t✐❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✼ ✷✳✶✳✶ ❆❣✐❧❡ ❉❡✈❡❧♦♣♠❡♥t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✼ ✷✳✶✳✷ ❯s✐♥❣ P❛tt❡r♥s ✷✾ ✷✳✶✳✸ ❘❡❛❞✐♥❣ ❛♥❞ ❲r✐t✐♥❣ ❈♦❞❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✶ ✷✳✶✳✹ ❉♦❝✉♠❡♥t❛t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✹ ✷✳✶✳✺ ❖♥✲▲✐♥❡ ❍❡❧♣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❈❧✐❡♥t✲❖r✐❡♥t❡❞ ✈s ❈♦♠♠✉♥✐t②✲❖r✐❡♥t❡❞ Pr♦❥❡❝ts ✷✳✷✳✶ Pr♦❥❡❝t ❊✈♦❧✉t✐♦♥ ✷✳✷✳✷ ❙✐♠✐❧❛r✐t✐❡s ❛♥❞ ❉✐✛❡r❡♥❝❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❲♦r❦✐♥❣ ♦♥ ❛ ❈❧✐❡♥t✲❖r✐❡♥t❡❞ Pr♦❥❡❝t ✷✳✸✳✶ ▼❡♠❜❡rs✱ ❘♦❧❡s✱ ❛♥❞ ❚❛s❦s ✷✳✸✳✷ ❚❡❛♠ ❉②♥❛♠✐❝s ✷✳✸✳✸ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✼ ✹✵ ✹✷ ✹✹ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✹ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✼ ❙❝❤❡❞✉❧✐♥❣✱ ▼✐❧❡st♦♥❡s✱ ❛♥❞ ❚♦✲❉♦ ▲✐sts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✽ ❏♦✐♥✐♥❣ ❛ ❈♦♠♠✉♥✐t②✲❖r✐❡♥t❡❞ Pr♦❥❡❝t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✵ ✈ ❈♦♥t❡♥ts ✈✐ ✷✳✺ ✷✳✹✳✶ Pr♦❥❡❝t ❙❡❧❡❝t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✳✹✳✷ ❋✐rst ❈♦♥t❛❝t ✇✐t❤ t❤❡ Pr♦❥❡❝t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✸ ✷✳✹✳✸ ◆♦r♠s ❢♦r ●♦♦❞ ❈✐t✐③❡♥s❤✐♣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✻ ✷✳✹✳✹ ❇❡❝♦♠✐♥❣ ❛ ❯s❡r ❋✐rst ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❙✉♠♠❛r② ❊①❡r❝✐s❡s ✸ ✸✳✷ ✸✳✸ ✸✳✹ ✻✵ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✵ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✳✶✳✶ ❆s②♥❝❤r♦♥♦✉s ❈♦♠♠✉♥✐❝❛t✐♦♥ ✸✳✶✳✷ ❙②♥❝❤r♦♥♦✉s ❈♦♠♠✉♥✐❝❛t✐♦♥ ✸✳✶✳✸ ❙❤❛r❡❞ ❉♦❝✉♠❡♥ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❈♦❞❡ ▼❛♥❛❣❡♠❡♥t ❚♦♦❧s ✻✹ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✺ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❚❤❡ ■❉❊ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✽ ❚❤❡ ❙♦❢t✇❛r❡ ❙t❛❝❦ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✵ ✸✳✷✳✸ ❚❤❡ ❱❡rs✐♦♥ ❈♦♥tr♦❧ ❙②st❡♠ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✷ ✸✳✷✳✹ ❚❤❡ ❇✉❣ ❚r❛❝❦❡r ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✼ ❘✉♥✲❚✐♠❡ ❙②st❡♠ ❈♦♥str❛✐♥ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✷ ✸✳✸✳✶ P❡r❢♦r♠❛♥❝❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✷ ✸✳✸✳✷ ❲❡❜ ❍♦st✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✸ ✸✳✸✳✸ ▲✐❝❡♥s✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✸ ✸✳✸✳✹ P❧❛t❢♦r♠ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✹ ❙✉♠♠❛r② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✹ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✺ ✽✼ ✹✳✶ ❆r❝❤✐t❡❝t✉r❛❧ P❛tt❡r♥s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✳✷ ▲❛②❡rs✱ ❈♦❤❡s✐♦♥✱ ❛♥❞ ❈♦✉♣❧✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❯s✐♥❣ ▼❡tr✐❝s t♦ ❊✈❛❧✉❛t❡ ❈♦❤❡s✐♦♥ ❛♥❞ ❈♦✉♣❧✐♥❣ ❙❡❝✉r✐t② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✾✺ ✾✻ ✹✳✸✳✷ ❯s❡r✲▲❡✈❡❧ ❙❡❝✉r✐t② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✳✺ ❙✉♠♠❛r② ❊①❡r❝✐s❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✾✼ ✶✵✵ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✺ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✺ ❲♦r❦✐♥❣ ✇✐t❤ ❈♦❞❡ ✺✳✸ ✽✾ ✾✸ ❆r❝❤✐t❡❝t✉r❛❧ ❱✉❧♥❡r❛❜✐❧✐t✐❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❈♦♥❝✉rr❡♥❝②✱ ❘❛❝❡ ❈♦♥❞✐t✐♦♥s✱ ❛♥❞ ❉❡❛❞❧♦❝❦s ✺✳✷ ✽✼ ✹✳✸✳✶ ✹✳✹ ✺✳✶ ✻✻ ✻✼ ✸✳✷✳✷ ❙♦❢t✇❛r❡ ❆r❝❤✐t❡❝t✉r❡ ✹✳✸ ✻✸ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✳✷✳✶ ✹✳✷✳✶ ✺ ✻✸ ❈♦❧❧❛❜♦r❛t✐♦♥ ❚♦♦❧s ❊①❡r❝✐s❡s ✹ ✺✽ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❯s✐♥❣ Pr♦❥❡❝t ❚♦♦❧s ✸✳✶ ✺✷ ❇❛❞ ❙♠❡❧❧s ❛♥❞ ▼❡tr✐❝s ✶✵✼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✽ ✺✳✶✳✶ ■❞❡♥t✐❢②✐♥❣ ❇❛❞ ❙♠❡❧❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✽ ✺✳✶✳✷ ❙♦❢t✇❛r❡ ▼❡tr✐❝s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✵ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✶ ✺✳✷✳✶ ❊①❛♠♣❧❡ ✶✿ ❘❡♠♦✈✐♥❣ ❯s❡❧❡ss ❋✉♥❝t✐♦♥s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✹ ✺✳✷✳✷ ❊①❛♠♣❧❡ ✷✿ ❘❡♠♦✈✐♥❣ ❛ ▲❛②❡r✐♥❣ ❱✐♦❧❛t✐♦♥ ✶✶✹ ❘❡❢❛❝t♦r✐♥❣ ❚❡st✐♥❣ ✺✳✸✳✶ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✼ ❯♥✐t ❚❡st✐♥❣ ❚♦♦❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✾ ❈♦♥t❡♥ts ✺✳✹ ✺✳✺ ✺✳✻ ✺✳✸✳✷ ❚❡st ❈❛s❡ ❉❡s✐❣♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✷✵ ✺✳✸✳✸ ❆ ❙tr❛t❡❣② ❢♦r ❙❡q✉❡♥❝✐♥❣ ❯♥✐t ❚❡sts ✶✷✽ ❉❡❜✉❣❣✐♥❣ ✶✷✾ ✺✳✹✳✶ ❚♦♦❧ ❯s❡ ✈s ❉❡✈❡❧♦♣❡r ❙❦✐❧❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✸✵ ✺✳✹✳✷ ❊①❛♠♣❧❡ ✶✿ ❆ ❯s❡r ■♥t❡r❢❛❝❡ ❇✉❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✸✶ ✺✳✹✳✸ ❊①❛♠♣❧❡ ✷✿ ❆ ▼✉❧t✐✲▲❡✈❡❧ ❇✉❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✸✸ ❊①t❡♥❞✐♥❣ t❤❡ ❙♦❢t✇❛r❡ ❢♦r ❛ ◆❡✇ Pr♦❥❡❝t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✸✹ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✸✺ ✺✳✺✳✶ ❆ ◆❡✇ ❯s❡ ❈❛s❡ ✺✳✺✳✷ ■♠♣❛❝t ♦♥ t❤❡ ❈♦❞❡ ❇❛s❡ ✺✳✺✳✸ ❚❡❛♠ ❉✐s❝✉ss✐♦♥s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❙✉♠♠❛r② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✳✷ ✻✳✸ ✻✳✹ ✻✳✺ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✹✵ ✶✹✸ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✹✸ ✻✳✶✳✶ ❘❡❛❞✐♥❣ ❛ ❉❡s✐❣♥ ❉♦❝✉♠❡♥t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✹✹ ✻✳✶✳✷ ❘❡❛❞✐♥❣ ❈♦❞❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✹✼ ✻✳✶✳✸ ❊①❛♠✐♥✐♥❣ t❤❡ ❉♦♠❛✐♥ ❈❧❛ss❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✺✵ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✺✶ ✻✳✷✳✶ ❆❞❞✐♥❣ ◆❡✇ ❋❡❛t✉r❡s ❚♦♣✲❉♦✇♥ ❆♥❛❧②s✐s✴❇♦tt♦♠✲❯♣ ❉❡✈❡❧♦♣♠❡♥t ✳ ✳ ✳ ✳ ✳ ✶✺✹ ✻✳✷✳✷ ▼♦❞✐❢②✐♥❣ t❤❡ ❉♦♠❛✐♥ ❈❧❛ss❡s ✶✺✺ ✻✳✷✳✸ ❉♦❝✉♠❡♥t❛t✐♦♥ ❛♥❞ ❇✉❧❧❡t♣r♦♦✜♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✺✽ ❈❧❛ss ❉❡s✐❣♥ Pr✐♥❝✐♣❧❡s ❛♥❞ Pr❛❝t✐❝❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✻✷ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✳✸✳✶ ❯s✐♥❣ ❲❤❛t✬s ❆❧r❡❛❞② ❚❤❡r❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✻✸ ✻✳✸✳✷ ❆❞❞✐♥❣ ❛ ◆❡✇ ❉♦♠❛✐♥ ❈❧❛ss ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✻✹ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✻✻ ▼❛♥❛❣✐♥❣ t❤❡ ❘✐♣♣❧❡ ❊✛❡❝t ✻✳✹✳✶ ❯♥✐t ❚❡st✐♥❣ t❤❡ ◆❡✇ ❈♦❞❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✻✻ ✻✳✹✳✷ ❘❡❢❛❝t♦r✐♥❣ t❤❡ ◆❡✇ ❈♦❞❡ ❇❛s❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✻✾ ❙✉♠♠❛r② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✼✶ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✼✶ ❉❡✈❡❧♦♣✐♥❣ t❤❡ ❉❛t❛❜❛s❡ ▼♦❞✉❧❡s ✼✳✷ ✼✳✸ ✶✸✾ ✶✹✵ ❯♥❞❡rst❛♥❞✐♥❣ t❤❡ ❈✉rr❡♥t ❙②st❡♠ ❊①❡r❝✐s❡s ✼✳✶ ✶✸✻ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❉❡✈❡❧♦♣✐♥❣ t❤❡ ❉♦♠❛✐♥ ❈❧❛ss❡s ✻✳✶ ✼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❊①❡r❝✐s❡s ✻ ✈✐✐ ❉❡s✐❣♥ Pr✐♥❝✐♣❧❡s ❛♥❞ Pr❛❝t✐❝❡ ✶✼✸ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✼✹ ✼✳✶✳✶ ❉❛t❛❜❛s❡ ❈r❡❛t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✼✺ ✼✳✶✳✷ ❈♦♥♥❡❝t✐♥❣ t❤❡ Pr♦❣r❛♠ t♦ t❤❡ ❉❛t❛❜❛s❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✼✻ ✼✳✶✳✸ ❚❛❜❧❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✼✽ ✼✳✶✳✹ ◆♦r♠❛❧✐③❛t✐♦♥ ❛♥❞ ❑❡②s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽✵ ✼✳✶✳✺ ❇❛❝❦✉♣ ❛♥❞ ❘❡❝♦✈❡r② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽✶ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽✷ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽✹ ❲♦r❦✐♥❣ ✇✐t❤ ❛ ❉❛t❛❜❛s❡ ✼✳✷✳✶ ❚❛❜❧❡ ❈r❡❛t✐♦♥ ✼✳✷✳✷ ❚❛❜❧❡ ❙❡❛r❝❤✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽✺ ✼✳✷✳✸ ❚❛❜❧❡ ■♥s❡rt✐♦♥✱ ❉❡❧❡t✐♦♥✱ ❛♥❞ ❯♣❞❛t✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽✼ ❉❛t❛❜❛s❡ ❙❡❝✉r✐t② ❛♥❞ ■♥t❡❣r✐t② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽✽ ✼✳✸✳✶ ❉❛t❛❜❛s❡✲▲❡✈❡❧ P❡r♠✐ss✐♦♥s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽✾ ✼✳✸✳✷ ❯s❡r✲▲❡✈❡❧ P❡r♠✐ss✐♦♥s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽✾ ❈♦♥t❡♥ts ✈✐✐✐ ✼✳✸✳✸ ✼✳✹ ✼✳✺ ■t❡♠s ✶ ❛♥❞ ✾❞✿ ❱♦❧✉♥t❡❡r ❙t❛t✉s ❛♥❞ ❆♣♣❧✐❝❛t✐♦♥ ✼✳✹✳✷ ■t❡♠ ✸✿ ❈❛❧❡♥❞❛r ❱✐❡✇ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❙✉♠♠❛r② ✳ ✳ ✽✳✷ ✽✳✸ ✽✳✹ ✾✳✸ ✷✵✷ ✷✵✺ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✵✺ ✽✳✶✳✶ ❚❤❡ ▼♦❞❡❧✲❱✐❡✇✲❈♦♥tr♦❧❧❡r P❛tt❡r♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✵✼ ✽✳✶✳✷ ❙❡ss✐♦♥s✱ ◗✉❡r② ❙tr✐♥❣s✱ ❛♥❞ ●❧♦❜❛❧ ❱❛r✐❛❜❧❡s ✳ ✳ ✳ ✳ ✳ ✷✶✵ ✽✳✶✳✸ ❊♥s✉r✐♥❣ ❙❡❝✉r✐t② ❛t t❤❡ ❯s❡r ■♥t❡r❢❛❝❡ ✷✶✸ ❲♦r❦✐♥❣ ✇✐t❤ ❈♦❞❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✶✽ ✽✳✷✳✶ ❘❡❛❞✐♥❣ ❉❡❡♣❧② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✶✾ ✽✳✷✳✷ ❉❡❜✉❣❣✐♥❣ ❛s ❛ ❈♦♠♠✉♥✐t② ❆❝t✐✈✐t② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❆❞❞✐♥❣ ◆❡✇ ❋❡❛t✉r❡s✿ ❯s❡r ■♥t❡r❢❛❝❡ ■♠♣❛❝t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✷✹ ✷✸✵ ✽✳✸✳✶ ■t❡♠ ✶✿ ❱♦❧✉♥t❡❡r ❙t❛t✉s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✸✵ ✽✳✸✳✷ ■t❡♠ ✷✿ ▼❛❦❡ ❆❝t✐✈❡✴■♥❛❝t✐✈❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✸✺ ✽✳✸✳✸ ■t❡♠ ✸✿ ❈❛❧❡♥❞❛r ❱✐❡✇ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❙✉♠♠❛r② ✷✸✼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✸✾ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✹✵ ✷✹✸ ❚❡❝❤♥✐❝❛❧ ❲r✐t✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✹✸ ✾✳✶✳✶ ❑♥♦✇✐♥❣ ❨♦✉r ❆✉❞✐❡♥❝❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✹✹ ✾✳✶✳✷ Pr✐♥❝✐♣❧❡s ♦❢ ●♦♦❞ ❲r✐t✐♥❣ ✷✹✻ ❚②♣❡s ♦❢ ❯s❡r ❙✉♣♣♦rt ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✹✾ ✾✳✷✳✶ ❖♥✲▲✐♥❡ ❍❡❧♣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✹✾ ✾✳✷✳✷ ❘❡❢❡r❡♥❝❡ ▼❛♥✉❛❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✺✶ ✾✳✷✳✸ ❖♣❡♥ ❉✐s❝✉ss✐♦♥ ❋♦r✉♠s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✺✸ ✾✳✷✳✹ ❯s❡r ❚r❛✐♥✐♥❣ ❛♥❞ ❋❡❡❞❜❛❝❦ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✺✼ ❊①❛♠♣❧❡✿ ❘▼❍ ❍♦♠❡❜❛s❡ ❖♥✲▲✐♥❡ ❍❡❧♣ ✾✳✸✳✶ ✾✳✹ ✶✾✽ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❯s❡r ❙✉♣♣♦rt ✾✳✷ ✶✾✸ ✶✾✺ ✷✵✶ ❉❡s✐❣♥ Pr✐♥❝✐♣❧❡s ❛♥❞ Pr❛❝t✐❝❡ ❊①❡r❝✐s❡s ✾✳✶ ✶✾✷ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❉❡✈❡❧♦♣✐♥❣ t❤❡ ❯s❡r ■♥t❡r❢❛❝❡ ✽✳✶ ✾ ✳ ✳ ✳ ✳ ✳ ✳ ✼✳✹✳✶ ❊①❡r❝✐s❡s ✽ ❈♦♥tr♦❧❧✐♥❣ ❈♦♥❝✉rr❡♥❝② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❆❞❞✐♥❣ ◆❡✇ ❙♦❢t✇❛r❡ ❋❡❛t✉r❡s✿ ❉❛t❛❜❛s❡ ■♠♣❛❝t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✺✽ ❍❡❧♣ ❛♥❞ t❤❡ ❈♦❞❡ ❇❛s❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✺✽ ❙✉♠♠❛r② ❊①❡r❝✐s❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✻✸ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✻✸ ✶✵ Pr♦❥❡❝t ●♦✈❡r♥❛♥❝❡ ✷✻✺ ✶✵✳✶ ❖r✐❣✐♥s ❛♥❞ ❊✈♦❧✉t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✳✶✳✶ ❙t❛rt✐♥❣ ❛ ❈❧✐❡♥t✲❖r✐❡♥t❡❞ Pr♦❥❡❝t ✶✵✳✶✳✷ ◗✉❛❧✐t② ❆ss❡ss♠❡♥t ✷✻✼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✼✶ ✶✵✳✷ ❊✈♦❧✈✐♥❣ ✐♥t♦ ❛ ❉❡♠♦❝r❛t✐❝ ▼❡r✐t♦❝r❛❝② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✳✷✳✶ ■♥❝✉❜❛t✐♦♥ ✶✵✳✷✳✷ ❖r❣❛♥✐③❛t✐♦♥ ✷✻✺ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✼✸ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✼✹ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✼✼ ✶✵✳✷✳✸ ❉❡❝✐s✐♦♥ ▼❛❦✐♥❣ ❛♥❞ ❈♦♥✢✐❝t ❘❡s♦❧✉t✐♦♥ ✶✵✳✷✳✹ ❉♦♠❛✐♥ ❈♦♥str❛✐♥ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✽✶ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✽✷ ❈♦♥t❡♥ts ✐① ✶✵✳✸ ❘❡❧❡❛s✐♥❣ ❈♦❞❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✳✸✳✶ ▲✐❝❡♥s✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✳✸✳✷ ❋✐♥❞✐♥❣ ❛ Pr♦❥❡❝t ❍♦st ✶✵✳✸✳✸ ❘❡❧❡❛s❡ ❙tr❛t❡❣✐❡s ✷✽✺ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✽✼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✽✾ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✾✵ ✶✵✳✹ ❙✉♠♠❛r② ❊①❡r❝✐s❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✽✹ ✷✽✹ ✶✶ ◆❡✇ Pr♦❥❡❝t ❈♦♥❝❡♣t✐♦♥ ✷✾✶ ✶✶✳✶ ❘❡q✉✐r❡♠❡♥ts ●❛t❤❡r✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✾✷ ✶✶✳✶✳✶ ❉♦♠❛✐♥ ❆♥❛❧②s✐s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✾✷ ✶✶✳✶✳✷ ❯s❡r ❙t♦r✐❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✾✺ ✶✶✳✶✳✸ ❯s❡ ❈❛s❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✾✼ ✶✶✳✷ ■♥✐t✐❛❧ ❉❡s✐❣♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵✸ ✶✶✳✷✳✶ ❉♦♠❛✐♥ ❈❧❛ss❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵✸ ✶✶✳✷✳✷ ❯s❡r ■♥t❡r❢❛❝❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵✹ ✶✶✳✷✳✸ P❡r❢♦r♠❛♥❝❡ ❛♥❞ P❧❛t❢♦r♠ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵✺ ✶✶✳✷✳✹ ❙②st❡♠ ❆r❝❤✐t❡❝t✉r❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵✼ ✶✶✳✷✳✺ ❉❡s✐❣♥ ❆❧t❡r♥❛t✐✈❡s ✸✵✽ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✳✷✳✻ ❉❡s✐❣♥ ❉♦❝✉♠❡♥t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✳✸ ❙✉♠♠❛r② ❊①❡r❝✐s❡s ✸✵✽ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵✾ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵✾ ❆♣♣❡♥❞✐❝❡s ✸✶✶ ❆ ❉❡t❛✐❧s ♦❢ t❤❡ ❈❛s❡ ❙t✉❞② ✸✶✶ ❆✳✶ ❆✳✷ ❘❡q✉✐r❡♠❡♥ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✶✶ ❆✳✶✳✶ ❉♦♠❛✐♥ ❆♥❛❧②s✐s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✶✷ ❆✳✶✳✷ ❯s❡ ❈❛s❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✶✼ ❆✳✶✳✸ ❙②st❡♠ ❘❡q✉✐r❡♠❡♥ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✷✼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✷✽ ❉❡s✐❣♥ ❆✳✷✳✶ ●♦❛❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❆✳✷✳✷ ❙♦❢t✇❛r❡ ❆r❝❤✐t❡❝t✉r❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✷✾ ❆✳✷✳✸ ❉♦♠❛✐♥ ❈❧❛ss❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✸✵ ❆✳✷✳✹ ❉❛t❛❜❛s❡ ❉❡s✐❣♥ ✸✸✵ ❆✳✷✳✺ ●❯■ ❉❡s✐❣♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✸✸ ❆✳✷✳✻ ■♠♣❧❡♠❡♥t❛t✐♦♥ ❙❝❤❡❞✉❧❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✸✻ ❆✳✷✳✼ ❯s❡r✲❙②st❡♠ ■♥t❡r❛❝t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✸✻ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❇ ◆❡✇ ❋❡❛t✉r❡s ❢♦r ❛♥ ❊①✐st✐♥❣ ❈♦❞❡ ❇❛s❡ ✸✷✾ ✸✹✶ ❇✳✶ ❙t❛rt✐♥❣ ✇✐t❤ ❛ ❘❡q✉❡st ❢r♦♠ t❤❡ ❈❧✐❡♥t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ❇✳✷ ■♠♣❛❝t ♦♥ t❤❡ ❉❡s✐❣♥ ❛♥❞ t❤❡ ❈♦❞❡ ❇❛s❡ ✸✹✶ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✹✸ ❇✳✸ ❉❡✜♥✐♥❣ ❛ Pr♦❥❡❝t t❤❛t ■♠♣❧❡♠❡♥ts t❤❡s❡ ❋❡❛t✉r❡s ✳ ✳ ✳ ✳ ✳ ✳ ✸✺✵ ❘❡❢❡r❡♥❝❡s ✸✺✶ ■♥❞❡① ✸✺✺ Appendix B New Features for an Existing Code Base ❚❤✐s ❆♣♣❡♥❞✐① s✉♠♠❛r✐③❡s t❤❡ ♦r✐❣✐♥s ❛♥❞ ♠♦t✐✈❛t✐♦♥ ❢♦r ❛❞❞✐♥❣ ♥❡✇ ❢❡❛t✉r❡s t♦ ❘▼❍ ❍♦♠❡❜❛s❡✳ ❚❤❡s❡ ♥❡✇ ❢❡❛t✉r❡s ♦r✐❣✐♥❛t❡ ❞✐r❡❝t❧② ❢r♦♠ t❤❡ ❝❧✐❡♥t✱ ✇❤♦ ❛t t❤❡ t✐♠❡ ❤❛❞ ❜❡❡♥ ✉s✐♥❣ ❘▼❍ ❍♦♠❡❜❛s❡ r❡❧❡❛s❡ ✶✳✹ ❢♦r ♦✈❡r ❛ ②❡❛r✳ ❚❤❡ ❛❝t✉❛❧ ✐♠♣❧❡♠❡♥t❛t✐♦♥ ♦❢ t❤❡s❡ ♥❡✇ ❢❡❛t✉r❡s ✐s ❞✐s❝✉ss❡❞ ✐♥ ❈❤❛♣t❡rs ✺✕ ✾ ♦❢ t❤❡ t❡①t✳ ❚❤❡ ✇♦r❦✐♥❣ ❝♦❞❡ ❜❛s❡ r❡❢❡r❡♥❝❡❞ ✐♥ t❤❡s❡ ❝❤❛♣t❡rs ❢♦r ✐❧❧✉s✲ tr❛t✐♥❣ t❤❡ ❞❡✈❡❧♦♣♠❡♥t ♦❢ t❤❡s❡ ♥❡✇ ❢❡❛t✉r❡s ✐s r❡❧❡❛s❡ ✷✳✵✱ ✇❤✐❝❤ ❝❛♥ ❜❡ ❞♦✇♥❧♦❛❞❡❞ ❢r♦♠ t❤❡ ❜♦♦❦✬s ❲❡❜ s✐t❡ ♠②♦♣❡♥s♦❢t✇❛r❡✳♦r❣✴t❡①t❜♦♦❦✳ B.1 Starting with a Request from the Client ❚❤❡ ❡✲♠❛✐❧ ❜❡❧♦✇ ❝❛♠❡ ❢r♦♠ t❤❡ ❝❧✐❡♥t t♦ t❤❡ ❧❡❛❞ ❞❡✈❡❧♦♣❡r✳ ■t ♦✉t❧✐♥❡s ❛ s❡r✐❡s ♦❢ ❢❡❛t✉r❡s t❤❛t ✇♦✉❧❞ ❜❡ ❞❡s✐r❛❜❧❡ t♦ ❛❞❞ t♦ ❘▼❍ ❍♦♠❡❜❛s❡✳ ❋r♦♠ t❤✐s ❡✲♠❛✐❧✱ ❛ s❡t ♦❢ ♥❡✇ r❡q✉✐r❡♠❡♥ts ❝❛♥ ❜❡ ❞❡✈❡❧♦♣❡❞✱ t❤❡✐r ✐♠♣❛❝t ♦♥ t❤❡ ❡①✐st✐♥❣ ❝♦❞❡ ❜❛s❡ ❝❛♥ ❜❡ ❡st✐♠❛t❡❞✱ ❛♥❞ ❛ ♣❧❛♥ ❢♦r ✐♠♣❧❡♠❡♥t❛t✐♦♥ ♦❢ t❤❡s❡ ♥❡✇ ❢❡❛t✉r❡s ❝❛♥ ❜❡ ❞❡✈❡❧♦♣❡❞✳ ❚❤❡s❡ st❡♣s ❛r❡ ♦✉t❧✐♥❡❞ ❧❛t❡r ✐♥ t❤✐s ❆♣♣❡♥❞✐①✱ ❛♥❞ t❤❡② ❜❡❝♦♠❡ t❤❡ ❜❛s✐s ❢♦r t❤❡ ❡①❛♠♣❧❡s ❛♥❞ ❡①❡r❝✐s❡s ✐♥ ❈❤❛♣t❡rs ✹✕✾✳ ❋r♦♠✿ ●✐♥❛ ❉❛t❡✿ ◆♦✈❡♠❜❡r ✾✱ ✷✵✵✾ ✶✵✿✺✶ ❆▼ ❚♦✿ ❆❧❡① ❙✉❜❥❡❝t✿ ❍♦♠❡❜❛s❡ ✐❞❡❛s ❆❧❡①✱ ❇❡❧♦✇ ✐s ❛ ❧✐st ♦❢ ✐❞❡❛s t❤❛t ❤❛✈❡ ❝♦♠❡ ❛❜♦✉t ✐♥ ✉s✐♥❣ ❍♦♠❡❜❛s❡✖ ✐❢ ②♦✉ ✇❛♥t t♦ ❣♦ t❤r♦✉❣❤ t❤❡♠ ♦✈❡r t❤❡ ♣❤♦♥❡✱ ♣❧❡❛s❡ ❣✐✈❡ ♠❡ ❛ ❝❛❧❧✳ ❚❤❛♥❦s✦ ✶✳ ❱♦❧✉♥t❡❡r st❛t✉s✖❛❜✐❧✐t② t♦ ❝❛t❡❣♦r✐③❡ ✈♦❧✉♥t❡❡rs ❛s ✐♥❛❝t✐✈❡ ♣r❡✈❡♥t✐♥❣ t❤❡♠ ❢r♦♠ s❤♦✇✐♥❣ ✉♣ ♦♥ ❛ s✉❜ ❧✐st✳ ❚❤✐s ✇♦✉❧❞ ✸✹✶ ✸✹✷ ❙♦❢t✇❛r❡ ❉❡✈❡❧♦♣♠❡♥t✿ ❆♥ ❖♣❡♥ ❙♦✉r❝❡ ❆♣♣r♦❛❝❤ ❜❡ ❤❡❧♣❢✉❧ t♦ ❡♥s✉r❡ ✈♦❧✉♥t❡❡rs ♦♥ ✈❛❝❛t✐♦♥ ♦r ♦t❤❡r✇✐s❡ ✉♥✲ ❛✈❛✐❧❛❜❧❡ ❞♦ ♥♦t ❣❡t ❝❛❧❧❡❞ ❢♦r s❤✐❢ts✳ ✷✳ ▼❛❦❡ ❛❝t✐✈❡✴✐♥❛❝t✐✈❡✖❛❜✐❧✐t② t♦ tr❛❝❦ ✇❤❡♥ ❛ ✈♦❧✉♥t❡❡r ❤❛s ❧❛st ❜❡❡♥ s❝❤❡❞✉❧❡❞ ❢♦r ❛ s❤✐❢t✳ ❋♦r ❡①❛♠♣❧❡✱ ✇❤❡♥ ❛ ♠❛♥❛❣❡r ❧♦❣s ✐♥ ❛ s❝r❡❡♥ ♣♦♣s ✉♣ s❤♦✇✐♥❣ t❤❡ ♥❛♠❡s ♦❢ ❛♥② ✈♦❧✉♥t❡❡r ✇❤♦ ❤❛s ♥♦t ❜❡❡♥ ♦♥ ❛ s❤✐❢t ❢♦r t❤❡ ♣❛st ♠♦♥t❤✳ ✸✳ ❈❛❧❡♥❞❛r ✈✐❡✇✖■♥ t❤❡ ❝✉rr❡♥t ❝❛❧❡♥❞❛r ✈✐❡✇✱ s❤✐❢t t✐♠❡s ❛r❡ ❤❛r❞ t♦ ❞✐st✐♥❣✉✐s❤ ✐❢ t❤❡ ✉s❡r ✐s ✉♥❢❛♠✐❧✐❛r ✇✐t❤ ✐t✳ ❋♦r ❡①✲ ❛♠♣❧❡✱ ✾✕✶✷ ❧♦♦❦s ❧✐❦❡ ✐t ❝♦✉❧❞ ❜❡ ✾✕✶✶✳ ▼♦r❡♦✈❡r✱ s♦♠❡t✐♠❡s ❛ s❤✐❢t ✭❡s♣❡❝✐❛❧❧② ❛ ✇❡❡❦❡♥❞ s❤✐❢t✮ ♥❡❡❞s ✐ts st❛rt ♦r ❡♥❞ t✐♠❡ t♦ ❜❡ ❝❤❛♥❣❡❞ ❜② t❤❡ ✉s❡r✳ ✹✳ ❈❛❧❡♥❞❛r ♠♦♥t❤ ✈✐❡✇✖■s ✐t ♣♦ss✐❜❧❡ t♦ ✈✐❡✇ ♦♥❡ ♠♦♥t❤ ❛t ❛ t✐♠❡❄ ❚❤✐s ✇♦✉❧❞ ❜❡ s✐♠♣❧② ❢♦r ❝♦♥✈❡♥✐❡♥❝❡ ❛♥❞ ✐s ♥♦t ❛ ♥❡❝❡ss✐t②✳ ✺✳ ■♠♣♦rt✴❡①♣♦rt✖♣♦ss✐❜❧❡ ✇✐t❤ ❘❛✐s❡r✬s ❊❞❣❡ ❞❛t❛❜❛s❡❄ ✻✳ ●✉❡st ❈❤❡❢✖■♥❢♦r♠❛t✐♦♥ ✐s ❡r❛s❡❞ ✐❢ ❛ ❝❤❛♥❣❡ ✐s ♠❛❞❡ t♦ t❤❡ ❝❛❧❡♥❞❛r ❛♥❞ t❤❡ ❞❛t❡ ❤❛s ♣❛ss❡❞✳ ❋♦r ❡①❛♠♣❧❡✱ ■ ❤❛✈❡ ❡♥t❡r❡❞ ✐♥❢♦ ✐♥ t❤❡ ❣✉❡st ❝❤❡❢ ✜❡❧❞ ❢♦r ✶✶✴✾✴✵✾✳ ❚♦♠♦rr♦✇ ✐❢ ✇❡ ♠❛❦❡ ❛ ❝❤❛♥❣❡✱ ▼♦♥❞❛②✬s ❣✉❡st ❝❤❡❢ ✐♥❢♦r♠❛t✐♦♥ ✇✐❧❧ ❜❡ ❞❡❧❡t❡❞✳ ■ ❛♠ t❡st✐♥❣ t❤✐s t♦❞❛② ❛♥❞ ✇✐❧❧ ❧❡t ②♦✉ ❦♥♦✇ ✐❢ ✐t ❤❛♣♣❡♥s ✇❤❡♥ ❛♥② ❝❤❛♥❣❡ ✐s ♠❛❞❡ ♦r ♦♥❧② ✐♥ t❤❡ ❣✉❡st ❝❤❡❢ ✜❡❧❞✳ ■ t❤✐♥❦ t❤❡ ✐ss✉❡ ✐s ♦♥❧② ✇✐t❤ t❤❡ ♥♦t❡ ✜❡❧❞ ✐♥ r❡❧❛t✐♦♥ t♦ ❣✉❡st ❝❤❡❢ ✐♥❢♦r♠❛t✐♦♥ ❜❡✐♥❣ ❞❡❧❡t❡❞✳ ■ ❥✉st ✇❡♥t ✐♥t♦ t❤❡ ❝❛❧❡♥❞❛r ❛♥❞ ♠❛❞❡ ❛ ❝❤❛♥❣❡ t♦ t❤❡ ♥♦t❡ ✜❡❧❞ ✉♥❞❡r ❋r✐❞❛②✬s ✸✲✻ P▼ s❤✐❢t✳ ❆❢t❡r ❝❧✐❝❦✐♥❣ t❤❡ s❛✈❡ ❜✉tt♦♥✱ ▼♦♥❞❛② ❛♥❞ ❚✉❡s❞❛②✬s ❣✉❡st ❝❤❡❢ ✐♥❢♦r♠❛t✐♦♥ ✇❛s ❞❡❧❡t❡❞✳ ■t ❞♦❡s ♥♦t ❤❛♣♣❡♥ ✇❤❡♥ ❝❤❛♥❣❡s ❛r❡ ♠❛❞❡ t♦ s❤✐❢ts✖❛❞❞✐♥❣✴r❡♠♦✈✐♥❣ ❛ ✈♦❧✉♥t❡❡r✳ ✼✳ ❱❛❝❛♥❝✐❡s ❛♥❞ s❤✐❢ts ✇♦r❦❡❞✖✐♥❢♦r♠❛t✐♦♥ ❢♦r t❤❡ ❍♦✉s❡ ▼❛♥✲ ❛❣❡r✿ ❛✳ ❙♦rt t❤❡ ✉♣❝♦♠✐♥❣ ✈❛❝❛♥❝✐❡s ♦♥ t❤❡ ♠❛♥❛❣❡r✬s s❝r❡❡♥ ❜② ❞❛t❡✳ ❜✳ ❚❤❡ t♦t❛❧ ❛♥❞ ❛✈❡r❛❣❡ ♥✉♠❜❡r ♦❢ ✈❛❝❛♥❝✐❡s ❢♦r ❡❛❝❤ ❞❛② ❛♥❞ s❤✐❢t✱ ❢♦r ❛♥② s❡r✐❡s ♦❢ ✇❡❡❦s ✐♥ t❤❡ ♣❛st✳ ❝✳ ❚❤❡ t♦t❛❧ ❛♥❞ ❛✈❡r❛❣❡ ♥✉♠❜❡r ♦❢ s❤✐❢ts ✇♦r❦❡❞ ❜② ❛♥② ✈♦❧✉♥t❡❡r✱ ❢♦r ❛♥② s❡r✐❡s ♦❢ ✇❡❡❦s ✐♥ t❤❡ ♣❛st✳ ✽✳ ❖♣❡♥ ❛♣♣❧✐❝❛t✐♦♥s✖s♦rt❡❞ ❜② ✜rst ♥❛♠❡ ❛♥❞ ✏❣r❛②❡❞ ♦✉t✑ ✐❢ t❤❡ ✐♥t❡r✈✐❡✇✱ ❜❛❝❦❣r♦✉♥❞ ♣❛♣❡r✇♦r❦✱ ♦r s❤❛❞♦✇ ❜✉tt♦♥s ❛r❡ s❡❧❡❝t❡❞✳ ❚❤❡ ✐♥❛❝t✐✈❡ ❢❡❛t✉r❡ ✇♦✉❧❞ ❜❡ ❤❡❧♣❢✉❧ ❤❡r❡ ❛s ✇❡❧❧✳ ❚❤❡r❡ ❛r❡ ♦❢t❡♥ ❛♣♣❧✐❝❛♥ts ✇❤♦ s✉❜♠✐t t❤❡✐r ✐♥❢♦r♠❛t✐♦♥ ❛♥❞ t❤❡♥ t❤❡② ◆❡✇ ❋❡❛t✉r❡s ❢♦r ❛♥ ❊①✐st✐♥❣ ❈♦❞❡ ❇❛s❡ ❞♦ ♥♦t ❝♦♠♣❧❡t❡ t❤❡ ❛♣♣❧✐❝❛t✐♦♥ ♣r♦❝❡ss✳ ✸✹✸ ❘❛t❤❡r t❤❛♥ ❧❡❛✈❡ t❤❡♠ ✐♥ t❤❡ ♦♣❡♥ ❛♣♣❧✐❝❛t✐♦♥ st❛t✉s t❤❡② ❝♦✉❧❞ ❜❡ ♠❛r❦❡❞ ❛s ✐♥❛❝t✐✈❡ ❛♥❞ t❤❡♥ ❝♦♠♣❧❡t❡❧② ❞❡❧❡t❡❞ ❛❢t❡r s❡✈❡r❛❧ ♠♦♥t❤s✳ ✾✳ ❱♦❧✉♥t❡❡r ❛♣♣❧✐❝❛t✐♦♥✿ ❛✳ ❆❧❧♦✇ ❢♦r s♣❛❝❡s ✐♥ t❤❡ ♥❛♠❡ ✜❡❧❞✳ ❊①❛♠♣❧❡✱ ❏♦ ❆♥♥✳ ❆❧s♦✱ r❡♠♦✈❡ t❤❡ ✏✫✑ ❢r♦♠ t❤❡ ✜rst ♥❛♠❡ ✜❡❧❞✳ ❊①❛♠♣❧❡✿ ❏❛❝❦ ✫ ❏✐❧❧✳ ❊♥tr✐❡s t❤❛t ❤❛✈❡ ✏✫✑ ❛r❡ ♥♦t ❛❝❝❡ss✐❜❧❡ ✐♥ t❤❡ ❞❛t❛❜❛s❡✳ ❜✳ ❆❧❧♦✇ ❢♦r ♦♥❧② t❤❡ ♠♦♥t❤✴②❡❛r ✜❡❧❞ t♦ ❜❡ ❝♦♠♣❧❡t❡❞ ✇❤❡♥ s❡❧❡❝t✐♥❣ ❛ st❛rt ❞❛t❡✳ ❝✳ ❲❤❡♥ ❛♥ ❛♣♣❧✐❝❛♥t ✜❧❧s ♦✉t t❤❡✐r ✐♥❢♦ ❛♥❞ ❝❧✐❝❦s s✉❜♠✐t t❤❡ s❝r❡❡♥ ❛♣♣❡❛rs ❜❧❛♥❦✳ P❡r❤❛♣s ❛♥ ❛✉t♦♠❛t✐❝ ♥♦t❡ t❤❛♥❦✐♥❣ t❤❡♠ ❢♦r s✉❜♠✐tt✐♥❣ ❛♥ ❛♣♣❧✐❝❛t✐♦♥✳ ❞✳ ❲❡ ♦✈❡r❧♦♦❦❡❞ t❤✐s ✇❤❡♥ ✜rst s✉❜♠✐tt✐♥❣ ✐♥❢♦r♠❛t✐♦♥ t♦ ②♦✉✿ ❝❛♥ ✜❡❧❞s ❜❡ ❛❞❞❡❞ s✉❝❤ ❛s ❡♠♣❧♦②❡r✬s ✐♥❢♦r♠❛t✐♦♥ ❛♥❞ ❡♠❡r❣❡♥❝② ❝♦♥t❛❝t❄ ✶✵✳ ▲♦❣✖■ ❧♦✈❡ t❤✐s ❢❡❛t✉r❡✦ ❈♦✉❧❞ t❤❡r❡ ❜❡ ❛♥ ❛❜✐❧✐t② t♦ ✈✐❡✇ ❛❞❞✐t✐♦♥❛❧ ♣❛❣❡s ❛s ✇❡ ❝❛♥ ✇✐t❤ t❤❡ ✏♣❡♦♣❧❡✿ ✈✐❡✇✑ t❛❜❄ ▲❡t ♠❡ ❦♥♦✇ ✇❤❛t ■ ❝❛♥ ❝❧❛r✐❢②✱ ❛♥❞ t❤❛♥❦ ②♦✉ ❛s ❛❧✇❛②s✦✖●✐♥❛ B.2 Impact on the Design and the Code Base ❙♦♠❡ ♦❢ t❤❡ ✐t❡♠s ✐♥ t❤✐s ❧✐st ❛r❡ r❡❛❧❧② ✏❜✉❣s✱✑ ❛♥❞ s♦ t❤❡② s❤♦✉❧❞ ❜❡ tr❡❛t❡❞ ❞✐✛❡r❡♥t❧② ❢r♦♠ t❤❡ ♦♥❡s ✇❤✐❝❤ ❛r❡ ❣❡♥✉✐♥❡❧② ♥❡✇ ❢❡❛t✉r❡s✳ ❖t❤❡rs ✐♠♣❛❝t t❤❡ ✉s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✱ ✇❤✐❧❡ st✐❧❧ ♦t❤❡rs ❣♦ ❞❡❡♣❡r ❛♥❞ ✐♠♣❛❝t t❤❡ ❞♦♠❛✐♥ ❝❧❛ss❡s ❛♥❞ ❝♦rr❡s♣♦♥❞✐♥❣ ❞❛t❛❜❛s❡ ♠♦❞✉❧❡s✳ ❙♦♠❡ ♦❢ t❤❡s❡ ✐t❡♠s ❛❧s♦ ♥❡❡❞ ♠♦r❡ ❝❧❛r✐✜❝❛t✐♦♥✱ s✉❝❤ ❛s t❤❡ r❡q✉❡st ❢♦r ❛♥ ✏✐♠♣♦rt✴❡①♣♦rt✑ ❢❡❛t✉r❡ ✭✐t❡♠ ★✺ ✐♥ t❤❡ ❧✐st✮✳ ❍❡r❡✱ ✇❡ ♠❛② ❛s❦ ✇❤❛t s❤♦✉❧❞ ❜❡ ✐♠♣♦rt❡❞✴❡①♣♦rt❡❞✖❛ ✈♦❧✉♥t❡❡r✬s ❞❛t❛✱ ❛ ❝❛❧❡♥❞❛r ✇❡❡❦✱ ♦r ♦t❤❡r ✐♥❢♦r♠❛t✐♦♥❄ ❲♦✉❧❞ t❤❡ ✐♠♣♦rt✴❡①♣♦rt ✉s❡ ❛ ❝♦♠♠❛✲s❡♣❛r❛t❡❞ ❧✐st t❤❛t ❝♦✉❧❞ ❜❡ ❝♦♣✐❡❞ ❛♥❞ ♣❛st❡❞ ✐♥t♦ ❛ s♣r❡❛❞s❤❡❡t❄ ❖r ✇♦✉❧❞ ✐t ✉s❡ ❛ s❡r✐❡s ♦❢ ▼②❙◗▲ ❞❛t❛❜❛s❡ q✉❡r✐❡s t❤❛t ❝❛♥ ❜❡ ✉s❡❞ t♦ ❜✉✐❧❞ t❛❜❧❡s ✐♥ ❛♥ ❡①t❡r♥❛❧ ❞❛t❛❜❛s❡❄ ❆♥ ❡①❛♠✐♥❛t✐♦♥ ♦❢ ❘❛✐s❡r✬s ❊❞❣❡ s♦❢t✇❛r❡ ❝♦✉❧❞ ❤❡❧♣ ❛♥s✇❡r s♦♠❡ ♦❢ t❤❡s❡ q✉❡st✐♦♥s✱ ❜✉t t❤❡ ♠♦st ✐♠♣♦rt❛♥t st❡♣ ❤❡r❡ ✇♦✉❧❞ ❜❡ t♦ t❛❧❦ ✇✐t❤ ●✐♥❛ t♦ ♦❜t❛✐♥ ♠♦r❡ ❝❧❛r✐✜❝❛t✐♦♥✳ ✶✳ ❱♦❧✉♥t❡❡r st❛t✉s✖❛❜✐❧✐t② t♦ ❝❛t❡❣♦r✐③❡ ❛ ✈♦❧✉♥t❡❡r ❛s ✐♥❛❝t✐✈❡ ♣r❡✲ ✈❡♥t✐♥❣ t❤❡♠ ❢r♦♠ s❤♦✇✐♥❣ ✉♣ ♦♥ ❛ s✉❜ ❧✐st✳ ❚❤✐s ✇♦✉❧❞ ❜❡ ❤❡❧♣❢✉❧ t♦ ❡♥s✉r❡ ✈♦❧✉♥t❡❡rs ♦♥ ✈❛❝❛t✐♦♥ ♦r ♦t❤❡r✇✐s❡ ✉♥❛✈❛✐❧❛❜❧❡ ❞♦ ♥♦t ❣❡t ❝❛❧❧❡❞ ❢♦r s❤✐❢ts✳ ❙♦❢t✇❛r❡ ❉❡✈❡❧♦♣♠❡♥t✿ ❆♥ ❖♣❡♥ ❙♦✉r❝❡ ❆♣♣r♦❛❝❤ ✸✹✹ ◆❛t✉r❡✿ ♥❡✇ ❢❡❛t✉r❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❞❡s✐❣♥✿ ❚❤❡ ❝✉rr❡♥t s②st❡♠ ❛ss✉♠❡s ❛❧❧ ✈♦❧✉♥t❡❡rs ❛r❡ ✏❛❝t✐✈❡✑ ❛♥❞ ❤❡♥❝❡ ❛r❡ ❡❧✐❣✐❜❧❡ t♦ ❜❡ s❝❤❡❞✉❧❡❞ ❢♦r s❤✐❢ts✳ ❙✉♣♣♦rt✐♥❣ t❤✐s ❢❡❛t✉r❡ ✇♦✉❧❞ r❡q✉✐r❡ ❛❞❞✐♥❣ ❛ ✏st❛t✉s✑ ✜❡❧❞ ❢♦r ❡❛❝❤ ✈♦❧✉♥t❡❡r✱ ✇✐t❤ ✈❛❧✉❡s ✏❛❝t✐✈❡✑ ♦r ✏✐♥❛❝t✐✈❡✳✑ ■♠♣❛❝t ♦♥ t❤❡ ❝♦❞❡ ❜❛s❡✿ ❉♦♠❛✐♥ ❝❧❛ss❡s✿ ❆❞❞ ❛ ♥❡✇ ✐♥st❛♥❝❡ ✈❛r✐❛❜❧❡ ✏st❛t✉s✑ t♦ t❤❡ P❡rs♦♥ ❝❧❛ss✱ ✇✐t❤ ❛♣♣r♦♣r✐❛t❡ ❝❤❛♥❣❡s t♦ ✐ts ❝♦♥str✉❝t♦rs ❛♥❞ ♦t❤❡r ❢✉♥❝t✐♦♥s✳ ❉❛t❛❜❛s❡ ♠♦❞✉❧❡s✿ ❆❞❞ ❛ ♥❡✇ ❝♦❧✉♠♥ ✏st❛t✉s✑ t♦ t❤❡ ❞❜P❡rs♦♥s t❛❜❧❡✱ ✇✐t❤ ❛♣♣r♦♣r✐❛t❡ ❝❤❛♥❣❡s t♦ t❤❡ s❡t✉♣ ❛♥❞ ♦t❤❡r r❡❧❛t❡❞ ❢✉♥❝t✐♦♥s✳ ❯s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✿ ❊✈❡r② ✉s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡ t❤❛t ✐♥✈♦❧✈❡s ❛ ♣❡r✲ s♦♥ s❤♦✉❧❞ ❜❡ ✉♣❞❛t❡❞ t♦ ❛❝❝♦♠♠♦❞❛t❡ t❤❡ ♥❡✇ ✏st❛t✉s✑ ✜❡❧❞✳ ❚❤❡s❡ ✐♥❝❧✉❞❡✿ ❡❞✐t▼❛st❡r❙❝❤❡❞✉❧❡ ❛♥❞ ❡❞✐t❙❤✐❢t ✭❧✐st✐♥❣ ♦♥❧② ✏❛❝t✐✈❡✑ ✈♦❧✉♥✲ t❡❡rs ✇❤❡♥ ✜❧❧✐♥❣ ❛ ✈❛❝❛♥❝②✮✱ ♣❡rs♦♥❊❞✐t ✭❛❞❞✐♥❣ ❛ ✏st❛t✉s✑ ✜❡❧❞✮✱ s✉❜✲ ❈❛❧❧▲✐st ✭❧✐st✐♥❣ ♦♥❧② ✏❛❝t✐✈❡✑ ✈♦❧✉♥t❡❡rs✮✱ s❡❛r❝❤P❡♦♣❧❡ ✭❛❞❞ ✏st❛t✉s✑ ❛s ❛ ✜❡❧❞ t♦ s❡❛r❝❤ ♦♥✮✱ ❛♥❞ ✈✐❡✇P❡rs♦♥ ✭❛❞❞✐♥❣ t❤❡ ♣❡rs♦♥✬s st❛t✉s t♦ t❤❡ ✈✐❡✇✮✳ ❯s❡r ❞♦❝✉♠❡♥t❛t✐♦♥✿ ◆♦ ♠♦❞✐✜❝❛t✐♦♥s ❛r❡ ♥❡❡❞❡❞✳ ✷✳ ▼❛❦❡ ❛❝t✐✈❡✴✐♥❛❝t✐✈❡✖❛❜✐❧✐t② t♦ tr❛❝❦ ✇❤❡♥ ❛ ✈♦❧✉♥t❡❡r ❤❛s ❧❛st ❜❡❡♥ s❝❤❡❞✉❧❡❞ ❢♦r ❛ s❤✐❢t✳ ❋♦r ❡①❛♠♣❧❡✱ ✇❤❡♥ ❛ ♠❛♥❛❣❡r ❧♦❣s ✐♥ ❛ s❝r❡❡♥ ♣♦♣s ✉♣ s❤♦✇✐♥❣ t❤❡ ♥❛♠❡s ♦❢ ❛♥② ✈♦❧✉♥t❡❡r ✇❤♦ ❤❛s ♥♦t ❜❡❡♥ ♦♥ ❛ s❤✐❢t ❢♦r t❤❡ ♣❛st ♠♦♥t❤✳ ◆❛t✉r❡✿ ♥❡✇ ❢❡❛t✉r❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❞❡s✐❣♥✿ ❚❤❡ ❝✉rr❡♥t s②st❡♠ ❞♦❡s ♥♦ s✉❝❤ tr❛❝❦✐♥❣✳ ❚❤✐s ❢❡❛t✉r❡ ❝♦✉❧❞ ❜❡ ❛❞❞❡❞ t♦ t❤❡ ♠❛♥❛❣❡r✬s ❤♦♠❡ ♣❛❣❡✱ ❣✐✈✐♥❣ ❤❡r t❤❡ ♦♣t✐♦♥ ♦❢ ♠❛r❦✐♥❣ ❡❛❝❤ s✉❝❤ ✈♦❧✉♥t❡❡r ❛s ✏✐♥❛❝t✐✈❡✑✳ ■♠♣❛❝t ♦♥ t❤❡ ❝♦❞❡ ❜❛s❡✿ ❉♦♠❛✐♥ ❝❧❛ss❡s✿ ♥♦♥❡ ✭❜❡②♦♥❞ ★✶ ❛❜♦✈❡✮✳ ❉❛t❛❜❛s❡ ♠♦❞✉❧❡s✿ ♥♦♥❡ ✭❜❡②♦♥❞ ★✶ ❛❜♦✈❡✮✳ ❯s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✿ ✐♥❞❡①✳♣❤♣ ✇♦✉❧❞ ♥❡❡❞ t♦ ❜❡ ♠♦❞✐✜❡❞ t♦ ✐♥❝❧✉❞❡ ❛ ❧✐st ♦❢ ✈♦❧✉♥t❡❡rs ✇❤♦ ❤❛❞ ♥♦t ❜❡❡♥ s❝❤❡❞✉❧❡❞ ❢♦r ❛t ❧❡❛st ❛ ♠♦♥t❤✱ ❛♥❞ ❛♥ ♦♣t✐♦♥ t♦ ♠❛r❦ ❡❛❝❤ ♦♥❡ ✏✐♥❛❝t✐✈❡✳✑ ♣❡rs♦♥❊❞✐t✳♣❤♣ s❤♦✉❧❞ ❛❧s♦ ❜❡ ❝❤❛♥❣❡❞ t♦ ❛❧❧♦✇ ❛ ✈♦❧✉♥t❡❡r✬s st❛t✉s t♦ ❜❡ ❝❤❛♥❣❡❞ ❜❡t✇❡❡♥ ✏❛❝t✐✈❡✑ ❛♥❞ ✏✐♥❛❝t✐✈❡✳✑ ❯s❡r ❞♦❝✉♠❡♥t❛t✐♦♥✿ ✐♥❞❡①❍❡❧♣✳✐♥❝✳♣❤♣ ♠✉st ❜❡ ♠♦❞✐✜❡❞ t♦ ❞❡s❝r✐❜❡ t❤✐s ♥❡✇ ❢✉♥❝t✐♦♥✳ ✸✳ ❈❛❧❡♥❞❛r ✈✐❡✇✖■♥ t❤❡ ❝✉rr❡♥t ❝❛❧❡♥❞❛r ✈✐❡✇✱ s❤✐❢t t✐♠❡s ❛r❡ ❤❛r❞ t♦ ❞✐st✐♥❣✉✐s❤ ✐❢ t❤❡ ✉s❡r ✐s ✉♥❢❛♠✐❧✐❛r ✇✐t❤ ✐t✳ ❋♦r ❡①❛♠♣❧❡✱ ✾✕✶✷ ❧♦♦❦s ❧✐❦❡ ✐t ❝♦✉❧❞ ❜❡ ✾✕✶✶✳ ▼♦r❡♦✈❡r✱ s♦♠❡t✐♠❡s ❛ s❤✐❢t ✭❡s♣❡❝✐❛❧❧② ❛ ✇❡❡❦❡♥❞ s❤✐❢t✮ ♥❡❡❞s ✐ts st❛rt ♦r ❡♥❞ t✐♠❡ t♦ ❜❡ ❝❤❛♥❣❡❞ ❜② t❤❡ ✉s❡r✳ ◆❛t✉r❡✿ ♥❡✇ ❢❡❛t✉r❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❞❡s✐❣♥✿ ❚❤✐s ✐s ❛ ♠♦r❡ ❝♦♠♣❧❡① r❡q✉❡st ❢♦r ❛ ♥❡✇ ❢❡❛t✉r❡✳ ■t r❛✐s❡s t❤❡ q✉❡st✐♦♥ ♦❢ ✇❤❡t❤❡r ♦r ♥♦t t♦ s❝r❛♣ t❤❡ ❝✉rr❡♥t ❛♣♣r♦❛❝❤ t❛❦❡♥ ❜② ❘▼❍ ❍♦♠❡❜❛s❡ t♦ ♠❛♥❛❣✐♥❣ t❤❡ ❝❛❧❡♥❞❛r ❛♥❞ r❡♣❧❛❝❡ ✐t ✇✐t❤ ◆❡✇ ❋❡❛t✉r❡s ❢♦r ❛♥ ❊①✐st✐♥❣ ❈♦❞❡ ❇❛s❡ ✸✹✺ ❛♥ ✐♥t❡❣r❛t❡❞ ✐❈❛❧❡♥❞❛r✲❝♦♠♣❛t✐❜❧❡ ♠♦❞✉❧❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❝♦❞❡ ❜❛s❡✿ ❙❝r❛♣♣✐♥❣ t❤❡ ❝✉rr❡♥t ❛♣♣r♦❛❝❤ t♦ t❤❡ ❝❛❧✲ ❡♥❞❛r ✇♦✉❧❞ ✐♠♣❛❝t ❛❧♠♦st ❛❧❧ ❝♦♠♣♦♥❡♥ts ♦❢ t❤❡ ❝♦❞❡ ❜❛s❡✳ ❑❡❡♣✐♥❣ t❤❡ ❛♣♣r♦❛❝❤ ✇♦✉❧❞ r❡q✉✐r❡ s✐❣♥✐✜❝❛♥t ❛❧t❡r❛t✐♦♥s t♦ s♦♠❡ ♦❢ t❤❡ ✉s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s s♦ t❤❛t t❤❡ ❍♦✉s❡ ▼❛♥❛❣❡r ❝❛♥ ❞②♥❛♠✐❝❛❧❧② r❡❞❡✜♥❡ t❤❡ st❛rt✴❡♥❞ t✐♠❡ ♦❢ ❛♥② s❤✐❢t✳ ❲❡ ✇✐❧❧ ❢❛✈♦r t❤❡ ❧❛tt❡r ❛♣♣r♦❛❝❤ ✐♥ t❤✐s t❡①t✳ ❉♦♠❛✐♥ ❝❧❛ss❡s✿ ❙❤✐❢t s❤♦✉❧❞ ❜❡ ❛❧t❡r❡❞ s♦ t❤❛t ✐ts st❛rt ❛♥❞ ❡♥❞ t✐♠❡ ❝❛♥ ❜❡ ❝❤❛♥❣❡❞ ✭✇✐t❤✐♥ t❤❡ s❛♠❡ ❞❛②✮✳ ❉❛t❛❜❛s❡ ♠♦❞✉❧❡s✿ ❞❜❙❤✐❢ts s❤♦✉❧❞ ❜❡ ❛❧t❡r❡❞ s♦ t❤❛t t❤❡ st❛rt ❛♥❞ ❡♥❞ t✐♠❡ ♦❢ ❛♥② s❤✐❢t ✐♥ t❤❡ ❞❛t❛❜❛s❡ ❝❛♥ ❜❡ ❝❤❛♥❣❡❞ ✭✇✐t❤✐♥ t❤❡ s❛♠❡ ❞❛②✮✳ ❯s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✿ ❝❛❧❡♥❞❛r✳♣❤♣ s❤♦✉❧❞ ❜❡ ♠♦❞✐✜❡❞ s♦ t❤❛t t❤❡ ❢✉♥❝t✐♦♥s t❤❛t ❞✐s♣❧❛② ❛ ✇❡❡❦ ♦❢ t❤❡ ❝❛❧❡♥❞❛r ❝❛♥ ✇♦r❦ ✇✐t❤ t❤❡ ♥❡✇ ❞❡✜♥✐t✐♦♥ ♦❢ ❛ s❤✐❢t✳ ❯s❡r ❞♦❝✉♠❡♥t❛t✐♦♥✿ ♠❛♥❛❣❡❈❛❧❡♥❞❛r❍❡❧♣✳✐♥❝✳♣❤♣ ✇♦✉❧❞ ♥❡❡❞ s✐❣♥✐✜✲ ❝❛♥t ♥❡✇ s❡❝t✐♦♥s✳ ✹✳ ❈❛❧❡♥❞❛r ♠♦♥t❤ ✈✐❡✇✖■s ✐t ♣♦ss✐❜❧❡ t♦ ✈✐❡✇ ♦♥❡ ♠♦♥t❤ ❛t ❛ t✐♠❡❄ ◆❛t✉r❡✿ ♥❡✇ ❢❡❛t✉r❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❞❡s✐❣♥✿ ❆ ♥❡✇ ❝❧❛ss ❛♥❞ ❞❛t❛❜❛s❡ t❛❜❧❡ ✇♦✉❧❞ ❜❡ ♥❡❡❞❡❞ t♦ st♦r❡ ❛❧❧ t❤❡ ❞❛②s ✐♥ ❡❛❝❤ ♠♦♥t❤✳ ❉♦♠❛✐♥ ❝❧❛ss❡s✿ ❆❞❞ ❛ ♥❡✇ ❝❧❛ss ▼♦♥t❤✱ ✇❤✐❝❤ ✐s ❛ s❡r✐❡s ♦❢ ❘▼❍❞❛t❡s✳ ❚❤✐s ❝♦✉❧❞ ❜❡ ♦r❣❛♥✐③❡❞ s✐♠✐❧❛r❧② t♦ t❤❡ ❡①✐st✐♥❣ ❝❧❛ss ❲❡❡❦✳ ❉❛t❛❜❛s❡ ♠♦❞✉❧❡s✿ ❆❞❞ ❛ ♥❡✇ ♠♦❞✉❧❡ ❞❜▼♦♥t❤s ✇❤✐❝❤ ❤❛s ♦♥❡ r♦✇ ❢♦r ❡❛❝❤ ❛❝t✐✈❡ ♦r ❛r❝❤✐✈❡❞ ♠♦♥t❤✳ ■t ✇♦✉❧❞ ❜❡ ♦r❣❛♥✐③❡❞ s✐♠✐❧❛r❧② t♦ t❤❡ ❡①✐st✐♥❣ ❝❧❛ss ❞❜❲❡❡❦s✳ ❯s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✿ ❆t t❤❡ t♦♣ ♦❢ t❤❡ ❝❛❧❡♥❞❛r ✈✐❡✇✱ ❛❞❞ ❛ ❜✉tt♦♥ ✏❱✐❡✇ ▼♦♥t❤✑ t❤❛t s❤♦✇s ❛♥ ❡♥t✐r❡ ♠♦♥t❤✳ ❊❛❝❤ ❞❛② ♦♥ t❤❡ ♠♦♥t❤ ✈✐❡✇ ✇♦✉❧❞ ❜❡ ❡✐t❤❡r ✇❤✐t❡ ♦r ❣r❛② ❞❡♣❡♥❞✐♥❣ ♦♥ ✇❤❡t❤❡r ✐t ❤❛s ❛ s❤✐❢t ✇✐t❤ ❛ ✈❛❝❛♥❝② ♦r ♥♦t✳ ❈❧✐❝❦✐♥❣ t❤❡ ♠♦✉s❡ ♦♥ t❤❛t ❞❛② ❜r✐♥❣s ②♦✉ ❜❛❝❦ t♦ ❛ ❝❛❧❡♥❞❛r ✇❡❡❦ ✈✐❡✇✱ ✇❤✐❝❤ s❤♦✇s t❤❛t ✇❡❡❦✬s ✈❛❝❛♥❝✐❡s ✐♥ ❞❡t❛✐❧ ✭❛s ✐t ❞♦❡s ♥♦✇✮✳ ❯s❡r ❞♦❝✉♠❡♥t❛t✐♦♥✿ ♠❛♥❛❣❡❈❛❧❡♥❞❛r❍❡❧♣✳✐♥❝✳♣❤♣ ✇♦✉❧❞ ♥❡❡❞ ❛ ♥❡✇ s❡❝t✐♦♥ t♦ ❞❡s❝r✐❜❡ ❤♦✇ t♦ ✉s❡ t❤✐s ♥❡✇ ❢❡❛t✉r❡✳ ✺✳ ■♠♣♦rt✴❡①♣♦rt✖♣♦ss✐❜❧❡ ✇✐t❤ ❘❛✐s❡r✬s ❊❞❣❡ ❞❛t❛❜❛s❡❄ ◆❛t✉r❡✿ ♥❡✇ ❢❡❛t✉r❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❞❡s✐❣♥✿ ❛♥② ♣❡rs♦♥✬s ❞❛t❛ ❝♦✉❧❞ ❜❡ ❡①♣♦rt❡❞ ✐♥t♦ ❛ ❝♦♠♠❛✲s❡♣❛r❛t❡❞ ❧✐st ❢♦r ✐♠♣♦rt✐♥❣ ✐♥t♦ ❛♥ ❊①❝❡❧✲t②♣❡ ♦❢ s♣r❡❛❞s❤❡❡t✳ ❉❛t❛ s♦ ❢♦r♠❛tt❡❞ ❝♦✉❧❞ ❜❡ ✐♠♣♦rt❡❞ t♦ ❝r❡❛t❡ ❛ ♥❡✇ P❡rs♦♥ ✐♥ t❤❡ ❞❛t❛❜❛s❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❝♦❞❡ ❜❛s❡✿ ❉♦♠❛✐♥ ❝❧❛ss❡s✿ ♥♦♥❡✳ ❉❛t❛❜❛s❡ ♠♦❞✉❧❡s✿ ❞❜P❡rs♦♥s ♥❡❡❞s ❛ ♥❡✇ ❢✉♥❝t✐♦♥ t❤❛t ✇♦✉❧❞ ❡①♣♦rt ❛♥ ❡♥tr② ✐♥ t❤❡ ❞❛t❛❜❛s❡ ✐♥t♦ ❛ t❡①t t❤❛t ❝♦✉❧❞ ❜❡ ❞♦✇♥❧♦❛❞❡❞ ❜② t❤❡ ✉s❡r✳ ❆♥♦t❤❡r ♥❡✇ ❢✉♥❝t✐♦♥ s❤♦✉❧❞ ❜❡ ❛❞❞❡❞ t❤❛t ✐♠♣♦rts ❛ ♣❡rs♦♥ ❛♥❞ ❙♦❢t✇❛r❡ ❉❡✈❡❧♦♣♠❡♥t✿ ❆♥ ❖♣❡♥ ❙♦✉r❝❡ ❆♣♣r♦❛❝❤ ✸✹✻ ❝r❡❛t❡s ❛ ♥❡✇ ❡♥tr② ✐♥ t❤❡ ❞❛t❛❜❛s❡✳ ❯s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✿ ❚❤✐s ❡①♣♦rt ❢✉♥❝t✐♦♥ ✇♦✉❧❞ ❜❡ ❛❞❞❡❞ t♦ t❤❡ ♣❡rs♦♥❊❞✐t ♠♦❞✉❧❡ ❛♥❞ ❜❡ ❛❝❝❡ss✐❜❧❡ ♦♥❧② t♦ t❤❡ ❍♦✉s❡ ▼❛♥❛❣❡r✳ ❯s❡r ❞♦❝✉♠❡♥t❛t✐♦♥✿ ❚❤❡ ❡❞✐tP❡rs♦♥❍❡❧♣✳♣❤♣ s❤♦✉❧❞ ❜❡ ♠♦❞✐✜❡❞ t♦ ❞❡s❝r✐❜❡ ❤♦✇ t♦ ✉s❡ t❤✐s ♥❡✇ ❢✉♥❝t✐♦♥✳ ✻✳ ●✉❡st ❈❤❡❢✖✐♥❢♦r♠❛t✐♦♥ ✐s ❡r❛s❡❞ ✐❢ ❛ ❝❤❛♥❣❡ ✐s ♠❛❞❡ t♦ t❤❡ ❝❛❧❡♥❞❛r ❛♥❞ t❤❡ ❞❛t❡ ❤❛s ♣❛ss❡❞✳ ❋♦r ❡①❛♠♣❧❡✱ ■ ❤❛✈❡ ❡♥t❡r❡❞ ✐♥❢♦ ✐♥ t❤❡ ❣✉❡st ❝❤❡❢ ✜❡❧❞ ❢♦r ✶✶✴✾✴✵✾✳ ❚♦♠♦rr♦✇ ✐❢ ✇❡ ♠❛❦❡ ❛ ❝❤❛♥❣❡✱ ▼♦♥❞❛②✬s ❣✉❡st ❝❤❡❢ ✐♥❢♦r♠❛t✐♦♥ ✇✐❧❧ ❜❡ ❞❡❧❡t❡❞✳ ■ ❛♠ t❡st✐♥❣ t❤✐s t♦❞❛② ❛♥❞ ✇✐❧❧ ❧❡t ②♦✉ ❦♥♦✇ ✐❢ ✐t ❤❛♣♣❡♥s ✇❤❡♥ ❛♥② ❝❤❛♥❣❡ ✐s ♠❛❞❡ ♦r ♦♥❧② ✐♥ t❤❡ ❣✉❡st ❝❤❡❢ ✜❡❧❞✳ ■ t❤✐♥❦ t❤❡ ✐ss✉❡ ✐s ♦♥❧② ✇✐t❤ t❤❡ ♥♦t❡ ✜❡❧❞ ✐♥ r❡❧❛t✐♦♥ t♦ ❣✉❡st ❝❤❡❢ ✐♥❢♦r♠❛t✐♦♥ ❜❡✐♥❣ ❞❡❧❡t❡❞✳ ■ ❥✉st ✇❡♥t ✐♥t♦ t❤❡ ❝❛❧❡♥❞❛r ❛♥❞ ♠❛❞❡ ❛ ❝❤❛♥❣❡ t♦ t❤❡ ♥♦t❡ ✜❡❧❞ ✉♥❞❡r ❋r✐❞❛②✬s ✸✲✻ P▼ s❤✐❢t✳ ❆❢t❡r ❝❧✐❝❦✐♥❣ t❤❡ s❛✈❡ ❜✉tt♦♥✱ ▼♦♥❞❛② ❛♥❞ ❚✉❡s❞❛②✬s ❣✉❡st ❝❤❡❢ ✐♥❢♦r♠❛t✐♦♥ ✇❛s ❞❡❧❡t❡❞✳ ■t ❞♦❡s ♥♦t ❤❛♣♣❡♥ ✇❤❡♥ ❝❤❛♥❣❡s ❛r❡ ♠❛❞❡ t♦ s❤✐❢ts✖❛❞❞✐♥❣✴r❡♠♦✈✐♥❣ ❛ ✈♦❧✉♥t❡❡r✳ ◆❛t✉r❡✿ ❜✉❣✳ ■♠♣❛❝t ♦♥ t❤❡ ❞❡s✐❣♥✿ ♥♦♥❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❝♦❞❡ ❜❛s❡✿ ♠✐♥♦r✳ ❉♦♠❛✐♥ ❝❧❛ss❡s✿ ♥♦♥❡✳ ❉❛t❛❜❛s❡ ♠♦❞✉❧❡s✿ ♥♦♥❡✳ ❯s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✿ ❝❛❧❡♥❞❛r✳♣❤♣ ✐s ✇❤❡r❡ t❤✐s ♣r♦❜❧❡♠ ❛r✐s❡s✱ ♣❛r✲ t✐❝✉❧❛r❧② ✇❤❡♥ t❤❡ ✏❙❛✈❡ ❝❤❛♥❣❡s t♦ ❛❧❧ ♥♦t❡s✑ ❜✉tt♦♥ ✐s s❡❧❡❝t❡❞✳ ❯s❡r ❞♦❝✉♠❡♥t❛t✐♦♥✿ ♥♦♥❡✳ ✼✳ ❱❛❝❛♥❝✐❡s ❛♥❞ s❤✐❢ts ✇♦r❦❡❞✖✐♥❢♦r♠❛t✐♦♥ ❢♦r t❤❡ ❍♦✉s❡ ▼❛♥❛❣❡r✿ ❛✳ ❙♦rt t❤❡ ✉♣❝♦♠✐♥❣ ✈❛❝❛♥❝✐❡s ♦♥ t❤❡ ♠❛♥❛❣❡r✬s s❝r❡❡♥ ❜② ❞❛t❡✳ ❜✳ ❚❤❡ t♦t❛❧ ❛♥❞ ❛✈❡r❛❣❡ ♥✉♠❜❡r ♦❢ ✈❛❝❛♥❝✐❡s ❢♦r ❡❛❝❤ ❞❛② ❛♥❞ s❤✐❢t✱ ❢♦r ❛♥② s❡r✐❡s ♦❢ ✇❡❡❦s ✐♥ t❤❡ ♣❛st✳ ❝✳ ❚❤❡ t♦t❛❧ ❛♥❞ ❛✈❡r❛❣❡ ♥✉♠❜❡r ♦❢ s❤✐❢ts ✇♦r❦❡❞ ❜② ❛♥② ✈♦❧✉♥t❡❡r✱ ❢♦r ❛♥② s❡r✐❡s ♦❢ ✇❡❡❦s ✐♥ t❤❡ ♣❛st✳ ◆❛t✉r❡✿ ♥❡✇ ❢❡❛t✉r❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❞❡s✐❣♥✿ t❤❡ ❝✉rr❡♥t s②st❡♠ ❧✐sts ✉♣❝♦♠✐♥❣ ✈❛❝❛♥❝✐❡s ✐♥ ♥♦ ♣❛rt✐❝✉❧❛r ♦r❞❡r✳ ■t ❞♦❡s ♥♦t r❡♣♦rt ❛♥② st❛t✐❝s ❧✐❦❡ t❤❡ ♦♥❡s ❞❡s✐r❡❞✳ ❆ ♥❡✇ ✉s❡ ❝❛s❡ s❤♦✉❧❞ ❜❡ ❞❡✜♥❡❞ t❤❛t ❞❡s❝r✐❜❡s t❤❡ ✉s❡r✲s②st❡♠ ✐♥t❡r❛❝✲ t✐♦♥ ❢♦r t❤✐s ❛❝t✐✈✐t②✳ ❙✉❝❤ ❛ ✉s❡ ❝❛s❡ ✇♦✉❧❞ ✐♥❝❧✉❞❡ t❤❡ ✐♠♣♦rt✴❡①♣♦rt ❢❡❛t✉r❡ ❞❡s❝r✐❜❡❞ ❡❛r❧✐❡r✳ ■♠♣❛❝t ♦♥ t❤❡ ❝♦❞❡ ❜❛s❡✿ s✐❣♥✐✜❝❛♥t✳ ❉♦♠❛✐♥ ❝❧❛ss❡s✿ ♥♦ ❝❤❛♥❣❡s✳ ❉❛t❛❜❛s❡ ♠♦❞✉❧❡s✿ ❆❞❞ ❢✉♥❝t✐♦♥s t♦ ❞❜❙❤✐❢s ❛♥❞ ❞❜❉❛t❡s t❤❛t ❛❝❝✉♠✉✲ ❧❛t❡ t❤❡ t♦t❛❧ ❛♥❞ ❛✈❡r❛❣❡ ♥✉♠❜❡rs ♦❢ ✈❛❝❛♥❝✐❡s ❢♦r ❡❛❝❤ s❤✐❢t ❛♥❞ ❞❛t❡ ♦✈❡r ❛♥② s❡r✐❡s ♦❢ ✇❡❡❦s✳ ◆❡✇ ❋❡❛t✉r❡s ❢♦r ❛♥ ❊①✐st✐♥❣ ❈♦❞❡ ❇❛s❡ ✸✹✼ ❯s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✿ ❆❞❞ t♦ t❤❡ ✈✐❡✇✳♣❤♣ ♠♦❞✉❧❡✳ ❘❡❢❛❝t♦r t❤❡ ✐♥✲ ❞❡①✳♣❤♣ ❛♥❞ ❡♥s✉r❡ t❤❛t t❤❡ ✉♣❝♦♠✐♥❣ ✈❛❝❛♥❝✐❡s ❛r❡ ♦r❞❡r❡❞ ❜② ❞❛t❡✳ ❍❡r❡ ❛❧s♦ ✐s ❛♥ ♦♣♣♦rt✉♥✐t② t♦ r❡❢❛❝t♦r t❤❡ ✐♥❞❡①✳♣❤♣ ❝♦❞❡ t♦ r❡♠♦✈❡ ✈✐♦❧❛t✐♦♥s ♦❢ t❤❡ ❧❛②❡r✐♥❣ ♣r✐♥❝✐♣❧❡✳ ❚❤✐s ✇♦✉❧❞ r❡q✉✐r❡ ❛❞❞✐♥❣ ❛ ♥❡✇ s❡❛r❝❤ ❢✉♥❝t✐♦♥ t♦ ❞❜❙❤✐❢ts✳ ❯s❡r ❞♦❝✉♠❡♥t❛t✐♦♥✿ ♥♦ ❝❤❛♥❣❡s ✽✳ ❖♣❡♥ ❛♣♣❧✐❝❛t✐♦♥s✖s♦rt❡❞ ❜② ✜rst ♥❛♠❡ ❛♥❞ ✏❣r❛②❡❞ ♦✉t✑ ✐❢ t❤❡ ✐♥✲ t❡r✈✐❡✇✱ ❜❛❝❦❣r♦✉♥❞ ♣❛♣❡r✇♦r❦✱ ♦r s❤❛❞♦✇ ❜✉tt♦♥s ❛r❡ s❡❧❡❝t❡❞✳ ❚❤❡ ✐♥❛❝t✐✈❡ ❢❡❛t✉r❡ ✇♦✉❧❞ ❜❡ ❤❡❧♣❢✉❧ ❤❡r❡ ❛s ✇❡❧❧✳ ❚❤❡r❡ ❛r❡ ♦❢t❡♥ ❛♣✲ ♣❧✐❝❛♥ts ✇❤♦ s✉❜♠✐t t❤❡✐r ✐♥❢♦r♠❛t✐♦♥ ❛♥❞ t❤❡♥ t❤❡② ❞♦ ♥♦t ❝♦♠♣❧❡t❡ t❤❡ ❛♣♣❧✐❝❛t✐♦♥ ♣r♦❝❡ss✳ ❘❛t❤❡r t❤❛♥ ❧❡❛✈❡ t❤❡♠ ✐♥ t❤❡ ♦♣❡♥ ❛♣♣❧✐❝❛t✐♦♥ st❛t✉s t❤❡② ❝♦✉❧❞ ❜❡ ♠❛r❦❡❞ ❛s ✐♥❛❝t✐✈❡ ❛♥❞ t❤❡♥ ❝♦♠♣❧❡t❡❧② ❞❡❧❡t❡❞ ❛❢t❡r s❡✈❡r❛❧ ♠♦♥t❤s✳ ◆❛t✉r❡✿ ♥❡✇ ❢❡❛t✉r❡ ■♠♣❛❝t ♦♥ t❤❡ ❞❡s✐❣♥✿ ❚❤❡ ❍♦✉s❡ ▼❛♥❛❣❡r✬s ❛♣♣❧✐❝❛♥t ❧✐st ✇♦✉❧❞ s❤♦✇ ❛♣♣❧✐❝❛♥ts ✏❣r❛②❡❞ ♦✉t✑ ✇❤❡♥ t❤❡✐r ♣r♦❝❡ss✐♥❣ ❤❛s ❜❡❣✉♥✳ ■♠♣❛❝t ♦♥ t❤❡ ❝♦❞❡ ❜❛s❡✿ ❉♦♠❛✐♥ ❝❧❛ss❡s✿ ♥♦♥❡✳ ❉❛t❛❜❛s❡ ♠♦❞✉❧❡s✿ ♥♦♥❡✳ ❯s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✿ ❈❤❛♥❣❡ ✐♥❞❡①✳♣❤♣ s♦ t❤❛t ✐t ❣r❛②s ♦✉t ❡✈❡r② ❛♣♣❧✐❝❛♥t ✇❤♦ ❤❛s ❜❡❣✉♥ ♣r♦❝❡ss✐♥❣ ♦r ✇❤♦ ❤❛s ❜❡❡♥ ♠❛r❦❡❞ ❛s ✏✐♥❛❝✲ t✐✈❡✑ ❢♦r ❧❛❝❦ ♦❢ ❛❝t✐✈✐t② ✐♥ t❤❡ ❧❛st ♠♦♥t❤✳ ❯s❡r ❞♦❝✉♠❡♥t❛t✐♦♥✿ ◆♦ ❝❤❛♥❣❡s ❛r❡ ♥❡❡❞❡❞✳ ✾✳ ❱♦❧✉♥t❡❡r ❛♣♣❧✐❝❛t✐♦♥ ❛✳ ❆❧❧♦✇ ❢♦r s♣❛❝❡s ✐♥ t❤❡ ♥❛♠❡ ✜❡❧❞✳ ❊①❛♠♣❧❡✿ ❏♦ ❆♥♥✳ ❆❧s♦✱ r❡♠♦✈❡ t❤❡ ✏✫✑ ❢r♦♠ t❤❡ ✜rst ♥❛♠❡ ✜❡❧❞✳ ❊①❛♠♣❧❡✿ ❏❛❝❦ ✫ ❏✐❧❧✳ ❊♥tr✐❡s t❤❛t ❤❛✈❡ ✏✫✑ ❛r❡ ♥♦t ❛❝❝❡ss✐❜❧❡ ✐♥ t❤❡ ❞❛t❛❜❛s❡✳ ❜✳ ❆❧❧♦✇ ❢♦r ♦♥❧② t❤❡ ♠♦♥t❤✴②❡❛r ✜❡❧❞ t♦ ❜❡ ❝♦♠♣❧❡t❡❞ ✇❤❡♥ s❡❧❡❝t✐♥❣ ❛ st❛rt ❞❛t❡✳ ❝✳ ❲❤❡♥ ❛♥ ❛♣♣❧✐❝❛♥t ✜❧❧s ♦✉t t❤❡✐r ✐♥❢♦ ❛♥❞ ❝❧✐❝❦s s✉❜♠✐t t❤❡ s❝r❡❡♥ ❛♣♣❡❛rs ❜❧❛♥❦✳ P❡r❤❛♣s ❛♥ ❛✉t♦♠❛t✐❝ ♥♦t❡ t❤❛♥❦✐♥❣ t❤❡♠ ❢♦r s✉❜✲ ♠✐tt✐♥❣ ❛♥ ❛♣♣❧✐❝❛t✐♦♥✳ ❞✳ ❲❡ ♦✈❡r❧♦♦❦❡❞ t❤✐s ✇❤❡♥ ✜rst s✉❜♠✐tt✐♥❣ ✐♥❢♦r♠❛t✐♦♥ t♦ ②♦✉✿ ❝❛♥ ✜❡❧❞s ❜❡ ❛❞❞❡❞ s✉❝❤ ❛s ❡♠♣❧♦②❡r✬s ✐♥❢♦r♠❛t✐♦♥ ❛♥❞ ❡♠❡r❣❡♥❝② ❝♦♥✲ t❛❝t❄ ◆❛t✉r❡✿ ■t❡♠ ❛ ✐s ❛ ❜✉❣ ❛♥❞ t❤❡ ♦t❤❡r t❤r❡❡ ❛r❡ ❢❡❛t✉r❡s✳ ■♠♣❛❝t ♦♥ t❤❡ ❞❡s✐❣♥✿ ❆❞❞ ✜❡❧❞s t♦ ❡❛❝❤ ♣❡rs♦♥✬s ❡♥tr② t♦ ❝♦♥t❛✐♥ ❡♠✲ ♣❧♦②❡r✬s ♥❛♠❡ ❛♥❞ ❛♥ ❡♠❡r❣❡♥❝② ❝♦♥t❛❝t ♥❛♠❡ ❛♥❞ ♣❤♦♥❡ ♥✉♠❜❡r✳ ■♠♣❛❝t ♦♥ t❤❡ ❝♦❞❡ ❜❛s❡✿ ❉♦♠❛✐♥ ❝❧❛ss❡s✿ ❆❞❞ ♥❡✇ ✜❡❧❞s ❛♥❞ ❛♣♣r♦♣r✐❛t❡ ❢✉♥❝t✐♦♥s t♦ t❤❡ P❡rs♦♥ ❝❧❛ss✳ ✸✹✽ ❙♦❢t✇❛r❡ ❉❡✈❡❧♦♣♠❡♥t✿ ❆♥ ❖♣❡♥ ❙♦✉r❝❡ ❆♣♣r♦❛❝❤ ❉❛t❛❜❛s❡ ♠♦❞✉❧❡s✿ ❆❞❞ ♥❡✇ ✜❡❧❞s ❛♥❞ ❛♣♣r♦♣r✐❛t❡ ❢✉♥❝t✐♦♥s t♦ t❤❡ ❞❜P❡rs♦♥s ♠♦❞✉❧❡✳ ❯s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✿ ▼♦❞✐❢② t❤❡ ♣❡rs♦♥❊❞✐t ❢♦r♠ t♦ ❛❝❝♦♠♠♦❞❛t❡ t❤❡s❡ ♥❡✇ ✜❡❧❞s ❛♥❞ ✜① t❤❡s❡ ❜✉❣s✳ ❋✐① t❤❡ s❡❛r❝❤P❡♦♣❧❡✳♣❤♣ ♠♦❞✉❧❡ s♦ t❤❛t ✐t ✜♥❞s ♣❡rs♦♥s ✇✐t❤ ❜❧❛♥❦s ✐♥ t❤❡✐r ✜rst ♥❛♠❡✳ ❯s❡r ❞♦❝✉♠❡♥t❛t✐♦♥✿ ◆♦ ❝❤❛♥❣❡s ❛r❡ ♥❡❡❞❡❞✳ ✶✵✳ ▲♦❣✖■ ❧♦✈❡ t❤✐s ❢❡❛t✉r❡✦ ❈♦✉❧❞ t❤❡r❡ ❜❡ ❛♥ ❛❜✐❧✐t② t♦ ✈✐❡✇ ❛❞❞✐t✐♦♥❛❧ ♣❛❣❡s ❛s ✇❡ ❝❛♥ ✇✐t❤ t❤❡ ✏♣❡♦♣❧❡✿ ✈✐❡✇✑ t❛❜❄ ◆❛t✉r❡✿ ♥❡✇ ❢❡❛t✉r❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❞❡s✐❣♥✿ ♥♦♥❡✳ ■♠♣❛❝t ♦♥ t❤❡ ❝♦❞❡ ❜❛s❡✿ ♠✐♥♦r✳ ❉♦♠❛✐♥ ❝❧❛ss❡s✿ ♥♦♥❡✳ ❉❛t❛❜❛s❡ ♠♦❞✉❧❡s✿ ♥♦♥❡✳ ❯s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✿ ✜① ❧♦❣✳♣❤♣ s♦ t❤❛t ✐t ❞✐s♣❧❛②s ✺✵ ❡♥tr✐❡s ❛t ❛ t✐♠❡ ✭❛s ❞♦❡s ✈✐❡✇✳♣❤♣ ❢♦r ✈✐❡✇✐♥❣ ♣❡rs♦♥s✮✱ ❛♥❞ ♣r♦✈✐❞❡s ❛ ♣❛❣❡r ❛t t❤❡ ❜♦tt♦♠ ❢♦r ♥❛✈✐❣❛t✐♦♥✳ ❯s❡r ❞♦❝✉♠❡♥t❛t✐♦♥✿ ◆♦ ❝❤❛♥❣❡s ❛r❡ ♥❡❡❞❡❞✳ ❋✐❣✉r❡ ❇✳✶ ❞❡s❝r✐❜❡s t❤❡ ✉s❡ ❝❛s❡ ❍♦✉s❡❝❧❡❛♥✐♥❣ t❤❛t ✐s s✉❣❣❡st❡❞ ❜② ❝♦♠❜✐♥✐♥❣ s❡✈❡r❛❧ ♦❢ t❤❡ ✐t❡♠s ✭✶✱ ✷✱ ✺✱ ❛♥❞ ✼✮ ❛❜♦✈❡✳ ◆❡✇ ❋❡❛t✉r❡s ❢♦r ❛♥ ❊①✐st✐♥❣ ❈♦❞❡ ❇❛s❡ ✸✹✾ ❍♦✉s❡❝❧❡❛♥✐♥❣ ❉❡s❝r✐♣t✐♦♥✿ ❖❝❝❛s✐♦♥❛❧❧②✱ t❤❡ ❍♦✉s❡ ▼❛♥❛❣❡r ♥❡❡❞s t♦ ✈✐❡✇ t❤❡ t♦t❛❧ ❛♥❞ ❛✈❡r❛❣❡ ♥✉♠❜❡r ♦❢ ✈❛❝❛♥❝✐❡s ❢♦r ❡❛❝❤ s❤✐❢t ❛♥❞ ❡❛❝❤ ❞❛②✱ ♦✈❡r ❛ ♣❡r✐♦❞ ♦❢ ✇❡❡❦s ✐♥ t❤❡ r❡❝❡♥t ♣❛st✳ ❱❛r✐♦✉s ♦t❤❡r ✐♥❢♦r♠❛t✐♦♥ ❛❜♦✉t ✈♦❧✉♥t❡❡r s❝❤❡❞✉❧❡s s❤♦✉❧❞ ❛❧s♦ ❜❡ r❡tr✐❡✈❛❜❧❡✱ s✉❝❤ ❛s t❤❡ t♦t❛❧ ❛♥❞ ❛✈❡r❛❣❡ ♥✉♠❜❡r ♦❢ s❤✐❢ts ✇♦r❦❡❞ ❜② ❛♥② ♣❛rt✐❝✉❧❛r ✈♦❧✉♥t❡❡r ❢♦r ❛♥② s✉❝❤ ♣❡r✐♦❞✱ ❛ ❧✐st ♦❢ ❛❝t✐✈❡ ✈♦❧✉♥t❡❡rs ✇❤♦ ❤❛✈❡ ♥♦t ❜❡❡♥ s❝❤❡❞✉❧❡❞ ❞✉r✐♥❣ t❤❛t ♣❡r✐♦❞✱ ❛♥❞ ❛ ❧✐st ♦❢ ❛❧❧ t❤❡ ✐♥❛❝t✐✈❡ ✈♦❧✉♥t❡❡rs✳ ❚❤❡ ❛❝✲ t✐✈❡✴✐♥❛❝t✐✈❡ st❛t✉s ♦❢ ❛♥② ♣❡rs♦♥ ♦♥ s✉❝❤ ❛ ❧✐st s❤♦✉❧❞ ❜❡ r❡✈❡rs✐❜❧❡✳ ❚❤❡ ❞❛t❛❜❛s❡ ❡♥tr✐❡s ❢♦r ❛♥② ❣r♦✉♣ ♦❢ ✈♦❧✉♥t❡❡rs s❤♦✉❧❞ ❜❡ ❡①♣♦rt❛❜❧❡ ❛s ❛ ❝♦♠♠❛✲s❡♣❛r❛t❡❞ ❧✐st s♦ t❤❛t t❤❡② ❝❛♥ ❜❡ ✐♠♣♦rt❡❞ ✐♥t♦ ❛ s♣r❡❛❞✲ s❤❡❡t ♦r ❛♥♦t❤❡r ❛♣♣❧✐❝❛t✐♦♥✳ ❆❝t♦r✿ t❤❡ ❍♦✉s❡ ▼❛♥❛❣❡r ●♦❛❧s✿ ❉✐✛❡r❡♥t s❡❧❡❝t✐♦♥s s❤♦✉❧❞ ❜❡ ♣♦ss✐❜❧❡✱ ✐♥ ♣❛rt✐❝✉❧❛r✿ ✏❱✐❡✇ t❤❡ t♦t❛❧ ❛♥❞ ❛✈❡r❛❣❡ ♥✉♠❜❡r ♦❢ ✈❛❝❛♥❝✐❡s ❢♦r ❡❛❝❤ ❞❛② ❛♥❞ s❤✐❢t✱ ♦✈❡r ❛♥② ♣❡r✐♦❞ ♦❢ t✐♠❡ ✐♥ t❤❡ ♣❛st✳✑ ✏❱✐❡✇ t❤❡ t♦t❛❧ ❛♥❞ ❛✈❡r❛❣❡ ♥✉♠❜❡r ♦❢ s❤✐❢ts ✇♦r❦❡❞ ❜② ❛♥② ✈♦❧✉♥✲ t❡❡r✱ ♦✈❡r ❛♥② ♣❡r✐♦❞ ♦❢ t✐♠❡ ✐♥ t❤❡ ♣❛st✳✑ ✏❱✐❡✇ ❛❧❧ ❛❝t✐✈❡ ✈♦❧✉♥t❡❡rs ✇❤♦ ❤❛✈❡ ♥♦t ❜❡❡♥ s❝❤❡❞✉❧❡❞ ❢♦r ❛ s❤✐❢t ♦✈❡r ❛♥② ♣❡r✐♦❞ ♦❢ t✐♠❡ ✭❝❤❛♥❣❡ t❤❡✐r st❛t✉s t♦ ✐♥❛❝t✐✈❡✮✳✑ ✏❱✐❡✇ ❛❧❧ ✐♥❛❝t✐✈❡ ✈♦❧✉♥t❡❡rs ✭❝❤❛♥❣❡ ❛♥②♦♥❡✬s st❛t✉s t♦ ❛❝t✐✈❡✮✳✑ ✏❊①♣♦rt t❤❡ ❞❛t❛❜❛s❡ ❡♥tr✐❡s ❢♦r ❛♥② ❣r♦✉♣ ♦❢ ✈♦❧✉♥t❡❡rs ✐♥ t❤❡ ❧✐st✳✑ Pr❡❝♦♥❞✐t✐♦♥s✿ ✶✳ ❆ ❜❡❣✐♥♥✐♥❣ ❛♥❞ ❡♥❞✐♥❣ ❞❛t❡ ❢♦r t❤❡ ♣❡r✐♦❞ ♦❢ t✐♠❡ ❤❛s ❜❡❡♥ s♣❡❝✐✜❡❞✳ ✷✳ ❖♥❡ ♦❢ t❤❡ ❛❜♦✈❡ s❡❧❡❝t✐♦♥s ❤❛s ❜❡❡♥ ♠❛❞❡✳ P♦st❝♦♥❞✐t✐♦♥s✿ ✶✳ ❚❤❡ ❞❡s✐r❡❞ ❧✐st ✐s ❞✐s♣❧❛②❡❞✱ ❛♥❞ s♦♠❡ ✈♦❧✉♥t❡❡rs✬ st❛t✉s ✐s ❝❤❛♥❣❡❞ ♦r t❤❡✐r ❞❛t❛ ✐s ❡①♣♦rt❡❞✳ ❘❡❧❛t❡❞ ❯s❡ ❈❛s❡s✿ ❱✐❡✇❆▲✐st ❙t❡♣s✿ ❆❝t♦r ❙②st❡♠ ✶✳ ▲♦❣ ♦♥ t♦ ❲❡❜ s✐t❡✳ ✷✳ ❆s❦ ❢♦r ✐❞ ❛♥❞ ♣❛ss✇♦r❞✳ ✸✳ ❊♥t❡r ✐❞ ❛♥❞ ♣❛ss✇♦r❞✳ ✹✳ ❱❡r✐❢② ❛♥❞ ❞✐s♣❧❛② ♦✉t❝♦♠❡✳ ✺✳ ■❞❡♥t✐❢② ❛ ♣❡r✐♦❞ ♦❢ t✐♠❡✳ ✻✳ ❘❡tr✐❡✈❡ s❤✐❢ts ❢♦r t❤❛t ♣❡r✐♦❞✳ ✼✳ ❙❡❧❡❝t ❛♥ ♦♣t✐♦♥✳ ✽✳ ❉✐s♣❧❛②✴❡①♣♦rt t❤♦s❡ s❤✐❢ts✳ ✾✳ ▲♦❣ ♦✛ ❲❡❜ s✐t❡✳ ✶✵✳ ❚❡r♠✐♥❛t❡ s❡ss✐♦♥✳ FIGURE B.1✿ ❯s❡ ❝❛s❡ ❍♦✉s❡❝❧❡❛♥✐♥❣✳ ✸✺✵ B.3 ❙♦❢t✇❛r❡ ❉❡✈❡❧♦♣♠❡♥t✿ ❆♥ ❖♣❡♥ ❙♦✉r❝❡ ❆♣♣r♦❛❝❤ Defining a Project that Implements these Features ◆♦✇ t❤❛t ✇❡ ❤❛✈❡ ❛ ❝❧❡❛r ✐❞❡❛ ♦❢ t❤❡ r❡q✉✐r❡♠❡♥ts ❛♥❞ t❤❡✐r ✐♠♣❛❝t ♦♥ t❤❡ ❝♦❞❡ ❜❛s❡✱ ❤❡r❡ ✐s ❛ ♣r♦❝❡ss t❤❛t ✇✐❧❧ ✐♠♣❧❡♠❡♥t t❤❡s❡ r❡q✉✐r❡♠❡♥ts ❛♥❞ ❞❡✈❡❧♦♣ ❛ ♥❡✇ ✈❡rs✐♦♥ ✷✳✵ ♦❢ ❘▼❍ ❍♦♠❡❜❛s❡✱ st❛rt✐♥❣ ✇✐t❤ t❤❡ ❝♦❞❡ ❜❛s❡ ❢♦r t❤❡ ❝✉rr❡♥t ✈❡rs✐♦♥ ✶✳✺✳ ✶✳ ❆❞❞r❡ss t❤❡ ❞❡❜✉❣❣✐♥❣ ❛♥❞ r❡❢❛❝t♦r✐♥❣ r❡q✉✐r❡♠❡♥ts✱ ❛s ❞✐s❝✉ss❡❞ ✐♥ ❈❤❛♣t❡r ✺✳ ✷✳ ❈♦♠♣❧❡t❡ t❤❡ ❞❡✈❡❧♦♣♠❡♥t ♦❢ t❤❡ ♥❡✇ ❡❧❡♠❡♥ts ♦❢ t❤❡ ❞♦♠❛✐♥ ❝❧❛ss❡s t❤❛t ❛r❡ ♥❡❡❞❡❞ t♦ ✐♠♣❧❡♠❡♥t t❤❡s❡ ♥❡✇ r❡q✉✐r♠❡♥ts✱ ❡①t❡♥❞ t❤❡ ✉♥✐t t❡sts✱ ❛♥❞ t❤❡♥ ✉♥✐t✲t❡st t❤❡ ❞♦♠❛✐♥ ❝❧❛ss❡s✳ ❚❤✐s ✐s ❞✐s❝✉ss❡❞ ❛s ❛ ❞❡t❛✐❧❡❞ ❡①❛♠♣❧❡ ✐♥ ❈❤❛♣t❡r ✻✳ ✸✳ ❈♦♠♣❧❡t❡ t❤❡ ❞❡✈❡❧♦♣♠❡♥t ♦❢ t❤❡ ♥❡✇ ❡❧❡♠❡♥ts ♦❢ t❤❡ ❞❛t❛❜❛s❡ ♠♦❞✉❧❡s t❤❛t ❛r❡ ♥❡❡❞❡❞ t♦ ✐♠♣❧❡♠❡♥t t❤❡s❡ ♥❡✇ r❡q✉✐r❡♠❡♥ts✱ ❡①t❡♥❞ t❤❡ ✉♥✐t t❡sts ❛♣♣r♦♣r✐❛t❡❧②✱ ❛♥❞ t❤❡♥ ✉♥✐t✲t❡st ❛❧❧ t❤❡ ❞❛t❛❜❛s❡ ♠♦❞✉❧❡s✳ ❚❤✐s ✐s ❞✐s❝✉ss❡❞ ❛s ❛ ❞❡t❛✐❧❡❞ ❡①❛♠♣❧❡ ✐♥ ❈❤❛♣t❡r ✼✳ ✹✳ ❈♦♠♣❧❡t❡ t❤❡ ❞❡✈❡❧♦♣♠❡♥t ♦❢ t❤❡ ♥❡✇ ❡❧❡♠❡♥ts ♦❢ t❤❡ ✉s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s t❤❛t ❛r❡ ♥❡❡❞❡❞ t♦ ✐♠♣❧❡♠❡♥t t❤❡s❡ ♥❡✇ r❡q✉✐r❡♠❡♥ts✱ ❡①t❡♥❞ t❤❡ ✉♥✐t t❡sts ❛♣♣r♦♣r✐❛t❡❧②✱ ❛♥❞ t❤❡♥ ✉♥✐t✲t❡st ❛❧❧ t❤❡ ✉s❡r ✐♥t❡r❢❛❝❡ ♠♦❞✉❧❡s✳ ❚❤✐s ✐s ❞✐s❝✉ss❡❞ ❛s ❛ ❞❡t❛✐❧❡❞ ❡①❛♠♣❧❡ ✐♥ ❈❤❛♣t❡r ✽✳ ✺✳ ❈♦♠♣❧❡t❡ t❤❡ ❞❡✈❡❧♦♣♠❡♥t ♦❢ t❤❡ r❡✈✐s✐♦♥s ♦❢ t❤❡ ♦♥✲❧✐♥❡ ❤❡❧♣ t❤❛t ❛r❡ ♥❡❡❞❡❞ t♦ s✉♣♣♦rt ❡✛❡❝t✐✈❡ ✉t✐❧✐③❛t✐♦♥ ♦❢ t❤❡s❡ ♥❡✇ ❢❡❛t✉r❡s✱ ❛♥❞ t❤❡♥ ✐♠♣❧❡♠❡♥t t❤❡♠✳ ❚❤✐s ✐s ❞✐s❝✉ss❡❞ ❛s ❛ ❞❡t❛✐❧❡❞ ❡①❛♠♣❧❡ ✐♥ ❈❤❛♣t❡r ✾✳ References ❈♦♠♣✉t✐♥❣ ❬❆❈▼✵✽❪ ❆❈▼✳ ❈✉rr✐❝✉❧❛ ✷✵✵✽✿ ❈♦♠♣✉t❡r ❙❝✐❡♥❝❡✳ ❆❈▼✴■❊❊❊ ❏♦✐♥t ❚❛s❦ ❋♦r❝❡ ♦♥ ❈♦♠♣✉t✐♥❣ ❈✉rr✐❝✉❧❛✱ ✷✵✵✽✳ ❬❇❇❈✵✾❪ ❇❇❈✳ ❯❑ ❣♦✈❡r♥♠❡♥t ❜❛❝❦s ♦♣❡♥ s♦✉r❝❡✳ ❖♥❧✐♥❡✱ ❋❡❜r✉❛r② ✷✵✵✾✳ ❬❈❉✵✼❪ ❙❛♠✐r ❈❤♦♣r❛ ❛♥❞ ❙❝♦tt ❉✳ ❉❡①t❡r✳ ❉❡❝♦❞✐♥❣ ▲✐❜❡r❛t✐♦♥✿ ❚❤❡ Pr♦♠✐s❡ ♦❢ ❋r❡❡ ❛♥❞ ❖♣❡♥ ❙♦✉r❝❡ ❙♦❢t✇❛r❡✳ ❘♦✉t❧❡❞❣❡ ❙t✉❞✐❡s ✐♥ ◆❡✇ ▼❡❞✐❛ ❛♥❞ ❈②❜❡r❝✉❧t✉r❡✳ ❘♦✉t❧❡❞❣❡✱ ✷✵✵✼✳ ❬❝♠♠❪ ❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇✐❦✐✴❝❛♣❛❜✐❧✐t②❴♠❛t✉r✐t②❴♠♦❞❡❧❴ ✐♥t❡❣r❛t✐♦♥✳ ❬❈♦❝✵✺❪ ❆❧✐st❛✐r ❈♦❝❦❜✉r♥✳ ❈r②st❛❧ ❈❧❡❛r✿ ❆ ❍✉♠❛♥✲P♦✇❡r❡❞ ▼❡t❤♦❞♦❧✲ ♦❣② ❢♦r ❙♠❛❧❧ ❚❡❛♠s✳ ❆❞❞✐s♦♥✲❲❡s❧❡②✱ ✷✵✵✺✳ ❬❈♦❞✼✵❪ ❊✳ ❋✳ ❈♦❞❞✳ ❆ r❡❧❛t✐♦♥❛❧ ♠♦❞❡❧ ♦❢ ❞❛t❛ ❢♦r ❧❛r❣❡ s❤❛r❡❞ ❞❛t❛ ❜❛♥❦s✳ ❈♦♠♠✉♥✐❝❛t✐♦♥s ♦❢ t❤❡ ❆❈▼✱ ✶✸✭✻✮✿✸✼✼✕✸✽✼✱ ❏✉♥❡ ✶✾✼✵✳ ❬❈♦♠✵✺❪ Pr❡s✐❞❡♥t✬s ■♥❢♦r♠❛t✐♦♥ ❚❡❝❤♥♦❧♦❣② ❆❞✈✐s♦r② ❈♦♠♠✐tt❡❡✳ ❈②❜❡r ❙❡❝✉r✐t②✿ ❆ ❈r✐s✐s ♦❢ Pr✐♦r✐t✐③❛t✐♦♥✳ ◆❛t✐♦♥❛❧ ❈♦♦r❞✐♥❛t✐♦♥ ❖❢✲ ✜❝❡ ❢♦r ■♥❢♦r♠❛t✐♦♥ ❚❡❝❤♥♦❧♦❣②✱ ❆r❧✐♥❣t♦♥✱ ❱❆✱ ❋❡❜r✉❛r② ✷✵✵✺✳ ❬❈♦♠✵✻❪ ❊✉r♦♣❡❛♥ ❈♦♠♠✐ss✐♦♥✳ ❊❝♦♥♦♠✐❝ ✐♠♣❛❝t ♦❢ ♦♣❡♥ s♦✉r❝❡ s♦❢t✲ ✇❛r❡ ♦♥ ✐♥♥♦✈❛t✐♦♥ ❛♥❞ t❤❡ ❝♦♠♣❡t✐t✐✈❡♥❡ss ♦❢ t❤❡ ✐♥❢♦r♠❛t✐♦♥ ❛♥❞ ❝♦♠♠✉♥✐❝❛t✐♦♥ t❡❝❤♥♦❧♦❣✐❡s ✭✐❝t✮ s❡❝t♦r ✐♥ t❤❡ ❊❯✳ ❖♥❧✐♥❡✱ ◆♦✈❡♠❜❡r ✷✵✵✻✳ ❬❈♦♥✵✼❪ ▲✐❜❡r❛❧ ❆rts ❈♦♠♣✉t❡r ❙❝✐❡♥❝❡ ❈♦♥s♦rt✐✉♠✳ ❆ ✷✵✵✼ ♠♦❞❡❧ ❝✉r✲ r✐❝✉❧✉♠ ❢♦r ❛ ❧✐❜❡r❛❧ ❛rts ❞❡❣r❡❡ ✐♥ ❝♦♠♣✉t❡r s❝✐❡♥❝❡✳ ❏♦✉r♥❛❧ ♦♥ ❊❞✉❝❛t✐♦♥❛❧ ❘❡s♦✉r❝❡s ✐♥ ❈♦♠♣✉t✐♥❣ ✭❏❊❘■❈✮✱ ✼✭✷✮✱ ❏✉♥❡ ✷✵✵✼✳ ❬❞■❞❙▲❪ ❋❡st✐✈❛❧ ▲❛t✐♥♦❛♠❡r✐❝❛♥♦ ❞❡ ■♥st❛❧❛❝✐ó♥ ❞❡ ❙♦❢t✇❛r❡ ▲✐❜r❡✳ ❤tt♣✿✴✴✇✇✇✳✐♥st❛❧❧❢❡st✳♥❡t✴✢✐s♦❧✷✵✶✵✳ + ❬❞❙❞❙❈ ✵✻❪ ❈❤❛♠✐♥❞r❛ ❞❡ ❙✐❧✈❛✱ ❘✳ ❞❡ ❙✐❧✈❛✱ ▼✐❢❛♥ ❈❛r❡❡♠✱ ▲♦✉✐q❛ ❘❛s❝❤✐❞✱ ❛♥❞ ❙✳ ❲❡❡r❛✇❛r❛♥❛✳ ❙❛❤❛♥❛✿ ❖✈❡r✈✐❡✇ ♦❢ ❛ ❞✐s❛st❡r ♠❛♥❛❣❡✲ ♠❡♥t s②st❡♠✳ Pr♦❝❡❡❞✐♥❣s ♦❢ t❤❡ ■❊❊❊ ■♥t❡r♥❛t✐♦♥❛❧ ❈♦♥❢❡r❡♥❝❡ ♦♥ ■♥❢♦r♠❛t✐♦♥ ❛♥❞ ❆✉t♦♠❛t✐♦♥✱ ✷✵✵✻✳ ❬❋♦❣✵✾❪ ❑❛r❧ ❋♦❣❡❧✳ Pr♦❞✉❝✐♥❣ ❖♣❡♥ ❙♦✉r❝❡ ❙♦❢t✇❛r❡✿ ❍♦✇ t♦ ❘✉♥ ❛ ❙✉❝❝❡ss❢✉❧ ❋r❡❡ ❙♦❢t✇❛r❡ Pr♦❥❡❝t✳ ❖✬❘❡✐❧❧②✱ ✷✵✵✾✳ ✸✺✶ ❘❡❢❡r❡♥❝❡s ✸✺✷ ❬❋♦✉❛❪ ❆♣❛❝❤❡ ❙♦❢t✇❛r❡ ❋♦✉♥❞❛t✐♦♥✳ ❤tt♣✿✴✴✇✇✇✳❛♣❛❝❤❡✳♦r❣✴✳ ❬❋♦✉❜❪ ❋r❡❡ ❙♦❢t✇❛r❡ ❋♦✉♥❞❛t✐♦♥✳ ❤tt♣✿✴✴✇✇✇✳❢s❢✳♦r❣✴❧✐❝❡♥s✐♥❣✴❧✐❝❡♥s❡s✴✳ ❬❋♦✉❝❪ ❋r❡❡ ❙♦❢t✇❛r❡ ❋♦✉♥❞❛t✐♦♥✳ ❤tt♣✿✴✴✇✇✇✳❣♥✉✳♦r❣✴❝♦♣②❧❡❢t✴❣♣❧✳❤t♠❧✳ ❬❋♦✉❞❪ ❋r❡❡ ❙♦❢t✇❛r❡ ❋♦✉♥❞❛t✐♦♥✳ ❤tt♣✿✴✴✇✇✇✳❣♥✉✳♦r❣✴♣❤✐❧♦s♦♣❤②✴ ❢r❡❡✲s✇✳❤t♠❧✳ ❬❋♦✉❡❪ ▼♦③✐❧❧❛ ❋♦✉♥❞❛t✐♦♥✳ ❤tt♣✿✴✴✇✇✇✳♠♦③✐❧❧❛✳♦r❣✴❛❜♦✉t✴✳ ❬❋♦✇✵✵❪ ▼❛rt✐♥ ❋♦✇❧❡r✳ ❘❡❢❛❝t♦r✐♥❣✿ ■♠♣r♦✈✐♥❣ t❤❡ ❉❡s✐❣♥ ♦❢ ❊①✐st✐♥❣ ❈♦❞❡✳ ❆❞❞✐s♦♥✲❲❡s❧❡②✱ ✷✵✵✵✳ ❬●◆❯❪ ●◆❯✳ ❤tt♣✿✴✴✇✇✇✳❣♥✉✳♦r❣✴❣♥✉✴✐♥✐t✐❛❧✲❛♥♥♦✉♥❝❡♠❡♥t✳❤t♠❧✳ ❬●r♦❛❪ ❙t❛♥❞✐s❤ ●r♦✉♣✳ ❤tt♣✿✴✴✇✇✇✳st❛♥❞✐s❤❣r♦✉♣✳❝♦♠✴♥❡✇sr♦♦♠✴ ❝❤❛♦s❴✷✵✵✾✳♣❤♣✳ ❬●r♦❜❪ ❙t❛♥❞✐s❤ ●r♦✉♣✳ ❤tt♣✿✴✴✇✇✇✳st❛♥❞✐s❤❣r♦✉♣✳❝♦♠✴♥❡✇sr♦♦♠✴ ♦♣❡♥❴s♦✉r❝❡✳♣❤♣✳ ❬❍✐❧✵✾❛❪ ●✐❥s ❍✐❧❧❡♥✐✉s✳ ❆♠st❡r❞❛♠ t♦ ♠❛❦❡ ❖♣❡♥❖✣❝❡ ❛♥❞ ❋✐r❡❋♦① ❞❡❢❛✉❧t ♦♥ ❝✐t② ❞❡s❦t♦♣s✳ ❖♥❧✐♥❡✱ ❆♣r✐❧ ✷✵✵✾✳ ❬❍✐❧✵✾❜❪ ●✐❥s ❍✐❧❧❡♥✐✉s✳ ❋r✿ ●❡♥❞❛r♠❡r✐❡ s❛✈❡s ♠✐❧❧✐♦♥s ✇✐t❤ ♦♣❡♥ ❞❡s❦t♦♣ ❛♥❞ ✇❡❜ ❛♣♣❧✐❝❛t✐♦♥s✳ ❖♥❧✐♥❡✱ ✷✵✵✾✳ ❬❍P❲✾✾❪ ❏✐♠ ❍❛♠❡r❧②✱ ❚♦♠ P❛q✉✐♥✱ ❛♥❞ ❙✉s❛♥ ❲❛❧t♦♥✳ s♦✉r❝❡✿ ❚❤❡ st♦r② ♦❢ ▼♦③✐❧❧❛✳ ❋r❡❡✐♥❣ t❤❡ ❖♣❡♥ ❙♦✉r❝❡s✿ ❱♦✐❝❡s ❢r♦♠ t❤❡ ❖♣❡♥ ❙♦✉r❝❡✱ ♣❛❣❡s ✶✾✼✕✷✵✻✱ ✶✾✾✾✳ ❬❏❙✶✵❪ ❈❤r✐s ❏❡♥s❡♥ ❛♥❞ ❲❛❧t ❙❝❛❝❝❤✐✳ ●♦✈❡r♥❛♥❝❡ ✐♥ ♦♣❡♥ s♦✉r❝❡ s♦❢t✲ ✇❛r❡ ❞❡✈❡❧♦♣♠❡♥t ♣r♦❥❡❝ts✳ ■♥ Pär ➴❣❡r❢❛❧❦✱ ❈♦r♥❡❧✐❛ ❇♦❧❞②r❡✛✱ ❏❡sús ▼✳ ●♦♥③á❧❡③✲❇❛r❛❤♦♥❛✱ ●r❡❣♦r② ❘✳ ▼❛❞❡②✱ ❛♥❞ ❏♦❤♥ ◆♦❧❧✱ ❡❞✐t♦rs✱ ❖♣❡♥ ❙♦✉r❝❡ ❙♦❢t✇❛r❡✿ ◆❡✇ ❍♦r✐③♦♥s✱ ✈♦❧✉♠❡ ✸✶✾✱ ♣❛❣❡s ✶✸✵✕✶✹✷✱ ❍❡✐❞❡❧❜❡r❣✱ ▼❛② ✷✵✶✵✳ ❙♣r✐♥❣❡r✳ ❬▼❝●✵✻❪ ●❛r② ▼❝●r❛✇✳ ❙♦❢t✇❛r❡ ❙❡❝✉r✐t②✿ ❇✉✐❧❞✐♥❣ ❙❡❝✉r✐t② ■♥✳ P❡❛rs♦♥ ❊❞✉❝❛t✐♦♥✱ ■♥❝✳✱ ✷✵✵✻✳ + ❬▼❚❉ ✵✾❪ ❘❛❧♣❤ ▼♦r❡❧❧✐✱ ❆❧❧❡♥ ❚✉❝❦❡r✱ ◆♦r♠❛♥ ❉❛♥♥❡r✱ ❚r✐s❤❛♥ ❞❡ ▲❛♥❡r♦❧❧❡✱ ❍❡✐❞✐ ❊❧❧✐s✱ ❖③❣✉r ■③♠✐r❧✐✱ ❉❛♥♥② ❑r✐③❛♥❝✱ ❛♥❞ ●❛r② P❛r❦❡r✳ ❘❡✈✐t❛❧✐③✐♥❣ ❝♦♠♣✉t✐♥❣ ❡❞✉❝❛t✐♦♥ t❤r♦✉❣❤ ❢r❡❡ ❛♥❞ ♦♣❡♥ s♦✉r❝❡ s♦❢t✇❛r❡ ❢♦r ❤✉♠❛♥✐t②✳ ❈♦♠♠✉♥✐❝❛t✐♦♥s ♦❢ t❤❡ ❆❈▼✱ ✺✷✭✽✮✿✻✼✕✼✺✱ ❆✉❣✉st ✷✵✵✾✳ ❬◆❇▼✵✽❪ ❉♦✉❣❧❛s ❙✳ ◆♦♦♥❛♥✱ P❛✉❧ ▼✳ ❆✳ ❇❛❦❡r✱ ❛♥❞ ◆❛t❤❛♥ ❲✳ ▼♦♦♥✳ ❖♣❡♥ s♦✉r❝❡ s♦❢t✇❛r❡ ♣♦t❡♥t✐❛❧ ✐♥❞❡① ✭♦s♣✐✮✿ ❉❡✈❡❧♦♣♠❡♥t ❝♦♥✲ s✐❞❡r❛t✐♦♥s✳ ❖♥❧✐♥❡✱ ✷✵✵✽✳ ❬❖❙■❪ ❖❙■✳ ❤tt♣✿✴✴✇✇✇✳♦♣❡♥s♦✉r❝❡✳♦r❣✴❧✐❝❡♥s❡s✳ ❘❡❢❡r❡♥❝❡s ✸✺✸ ❬P❡r❪ ❇r✉❝❡ P❡r❡♥s✳ ❤tt♣✿✴✴s❧❛s❤❞♦t✳♦r❣✴❛rt✐❝❧❡s✴✾✾✴✵✷✴✶✽✴ ✵✾✷✼✷✵✷✳s❤t♠❧✳ ❬P❡r✾✾❪ ❇r✉❝❡ P❡r❡♥s✳ ❖♣❡♥ s♦✉r❝❡s✿ ❱♦✐❝❡s ❢r♦♠ t❤❡ ♦♣❡♥ s♦✉r❝❡ r❡✈♦✲ ❧✉t✐♦♥✳ ❚❤❡ ❖♣❡♥ ❙♦✉r❝❡ ■♥✐t✐❛t✐✈❡✱ ♣❛❣❡s ✶✼✶✕✶✽✽✱ ✶✾✾✾✳ ❬❘❛②✵✵❪ ❊r✐❝ ❙t❡✈❡♥ ❘❛②♠♦♥❞✳ ❚❤❡ ❈❛t❤❡❞r❛❧ ❛♥❞ t❤❡ ❇❛③❛❛r✳ ❖✬❘❡✐❧❧②✱ ✷✵✵✵✳ ❬❘❛②✵✶❪ ❊r✐❝ ❙t❡✈❡♥ ❘❛②♠♦♥❞✳ ❚❤❡ ❈❛t❤❡❞r❛❧ ❛♥❞ t❤❡ ❇❛③❛❛r✳ ❖✬❘❡✐❧❧②✱ ✷✵✵✶✳ ❬❙❛❧✵✽❪ P❡t❡r ❍✳ ❙❛❧✉s✳ ❚❤❡ ❉❛❡♠♦♥✱ t❤❡ ●♥✉✱ ❛♥❞ t❤❡ P❡♥❣✉✐♥✿ ❍♦✇ ❢r❡❡ ❛♥❞ ♦♣❡♥ s♦✉r❝❡ s♦❢t✇❛r❡ ✐s ❝❤❛♥❣✐♥❣ t❤❡ ✇♦r❧❞✳ ❘❡❡❞ ▼❡❞✐❛ ❙❡r✈✐❝❡s✱ ✷✵✵✽✳ ❬❙t❛❛❪ ❘✐❝❤❛r❞ ❙t❛❧❧♠❛♥✳ ❤tt♣✿✴✴✇✇✇✳❣♥✉✳♦r❣✴❣♥✉✴♠❛♥✐❢❡st♦✳❤t♠❧✳ ❬❙t❛❜❪ ❘✐❝❤❛r❞ ❙t❛❧❧♠❛♥✳ ❤tt♣✿✴✴✇✇✇✳❣♥✉✳♦r❣✴♣❤✐❧♦s♦♣❤②✴✉s❡✲❢r❡❡✲ s♦❢t✇❛r❡✳❤t♠❧✳ ❚❤❡ ●◆❯ ❖♣❡r❛t✐♥❣ ❙②st❡♠ ❛♥❞ t❤❡ ❋r❡❡ ❬❙t❛✾✾❪ ❘✐❝❤❛r❞ ❙t❛❧❧♠❛♥✳ ❙♦❢t✇❛r❡ ▼♦✈❡♠❡♥t✳ ❖✬❘❡✐❧❧②✱ ✶✾✾✾✳ ❬❙t❛✵✾❪ ❘✐❝❤❛r❞ ❙t❛❧❧♠❛♥✳ s♦❢t✇❛r❡✳ ❲❤② ❵♦♣❡♥ s♦✉r❝❡✬ ♠✐ss❡s t❤❡ ♣♦✐♥t ♦❢ ❢r❡❡ ❈♦♠♠✉♥✐❝❛t✐♦♥s ♦❢ t❤❡ ❆ss♦❝✐❛t✐♦♥ ❢♦r ❈♦♠♣✉t✐♥❣ ▼❛❝❤✐♥❡r②✱ ✺✷✭✻✮✿✸✶✕✸✸✱ ❏✉♥❡ ✷✵✵✾✳ ❬❚✐❞✵✺❪ ❏❡♥✐❢❡r ❚✐❞✇❡❧❧✳ ❉❡s✐❣♥✐♥❣ ■♥t❡r❢❛❝❡s✿ P❛tt❡r♥s ❢♦r ❊✛❡❝t✐✈❡ ■♥✲ t❡r❛❝t✐♦♥ ❉❡s✐❣♥✳ ❖✬❘❡✐❧❧②✱ ✷✵✵✺✳ ❬❚♦r✾✶❪ ▲✐♥✉s ❚♦r✈❛❧❞s✳ ❲❤❛t ✇♦✉❧❞ ②♦✉ ❧✐❦❡ t♦ s❡❡ ♠♦st ✐♥ ♠✐♥✐①❄ ❯❙❊◆❊❚✱ ❆✉❣✉st ✶✾✾✶✳ ❬❚♦r✾✾❪ ▲✐♥✉s ❚♦r✈❛❧❞s✳ ❚❤❡ ▲✐♥✉① ❊❞❣❡✳ ❖✬❘❡✐❧❧②✱ ✶✾✾✾✳ ❬✉♠❧❪ ❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇✐❦✐✴✉♥✐✜❡❞❴♠♦❞❡❧✐♥❣❴❧❛♥❣✉❛❣❡✳ ❬❲❤❡❪ ❉❛✈✐❞ ❆✳ ❲❤❡❡❧❡r✳ ❤tt♣✿✴✴✇✇✇✳❞✇❤❡❡❧❡r✳❝♦♠✴❡ss❛②s✴✢♦ss✲ ❧✐❝❡♥s❡✲s❧✐❞❡✳❤t♠❧✳ ❬✇♣✲❛❪ ❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇✐❦✐✴ ❜r♦✇s❡r❴✇❛rs✳ ❬✇♣✲❜❪ ❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇✐❦✐✴✷✵✵✹❴✐♥❞✐❛♥❴♦❝❡❛♥❴❡❛rt❤q✉❛❦❡✳ ❬✇♣✲❝❪ ❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇✐❦✐✴❢r❡❡❴s♦❢t✇❛r❡✳ ❬✇♣✲❞❪ ❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇✐❦✐✴❣♥✉❴❣❡♥❡r❛❧❴♣✉❜❧✐❝❴❧✐❝❡♥s❡✳ ❬✇♣✲❡❪ ❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇✐❦✐✴❤✐st♦r②❴♦❢❴❧✐♥✉①✳ ❬✇♣✲❢ ❪ ❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇✐❦✐✴❧✐♥✉①❴❦❡r♥❡❧✳ ❘❡❢❡r❡♥❝❡s ✸✺✹ ❬✇♣✲❣❪ ❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇✐❦✐✴ s❛❤❛♥❛❴❢♦ss❴❞✐s❛st❡r❴♠❛♥❛❣❡♠❡♥t❴s②st❡♠✳ ❬✇♣✲❤❪ ❤tt♣✿✴✴❡♥✳✇✐❦✐♣❡❞✐❛✳♦r❣✴✇✐❦✐✴✉s❴✈s✳❴♠✐❝r♦s♦❢t✳ ❬❨♦✉✾✾❪ ❘♦❜❡rt ❨♦✉♥❣✳ ●✐✈✐♥❣ ✐t ❛✇❛②✿ ❍♦✇ r❡❞ ❤❛t s♦❢t✇❛r❡ st✉♠❜❧❡❞ ❛❝r♦ss ❛ ♥❡✇ ❡❝♦♥♦♠✐❝ ♠♦❞❡❧ ❛♥❞ ❤❡❧♣❡❞ ✐♠♣r♦✈❡ ❛♥ ✐♥❞✉str②✳ ❖♣❡♥ ❙♦✉r❝❡s✿ ❱♦✐❝❡s ❢r♦♠ t❤❡ ❖♣❡♥ ❙♦✉r❝❡ ❘❡✈♦❧✉t✐♦♥✱ ♣❛❣❡s ✶✶✸✕✶✷✻✱ ✶✾✾✾✳ .. .SOFTWARE DEVELOPMENT AN OPEN SOURCE APPROACH Chapman & Hall/CRC Innovations in Software Engineering and Software Development Series Editor Richard LeBlanc... The Current Practice Vaclav Rajlich CHAPMAN & HALL/CRC INNOVATIONS IN SOFTWARE ENGINEERING AND SOFTWARE DEVELOPMENT SOFTWARE DEVELOPMENT AN OPEN SOURCE APPROACH ALLEN TUCKER RALPH MORELLI CHAMINDRA... Titles Software Development: An Open Source Approach Allen Tucker, Ralph Morelli, and Chamindra de Silva Forthcoming Titles Fundamentals of Dependable Computing for Software Engineers John Knight Software