SPRINGER BRIEFS IN APPLIED SCIENCES AND TECHNOLOGY Fan Yang Ping Duan Sirish L. Shah Tongwen Chen Capturing Connectivity and Causality in Complex Industrial Processes 123 SpringerBriefs in Applied Sciences and Technology For furthervolumes: http://www.springer.com/series/8884 Fan Yang Ping Duan Sirish L. Shah • • Tongwen Chen Capturing Connectivity and Causality in Complex Industrial Processes 123 Fan Yang Sirish L.Shah TsinghuaLaboratory forInformation Department of Chemical andMaterials Scienceand Technology Engineering Department ofAutomation Universityof Alberta TsinghuaUniversity Edmonton, AB Beijing Canada China Ping Duan Tongwen Chen Department of Electricaland Computer Engineering Universityof Alberta Edmonton, AB Canada ISSN 2191-530X ISSN 2191-5318 (electronic) ISBN 978-3-319-05379-0 ISBN 978-3-319-05380-6 (eBook) DOI 10.1007/978-3-319-05380-6 Springer ChamHeidelberg New YorkDordrecht London LibraryofCongressControlNumber:2014934663 (cid:2)TheAuthor(s)2014 Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpartof the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation,broadcasting,reproductiononmicrofilmsorinanyotherphysicalway,andtransmissionor informationstorageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifically for the purposeofbeingenteredandexecutedonacomputersystem,forexclusiveusebythepurchaserofthe work. Duplication of this publication or parts thereof is permitted only under the provisions of theCopyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the CopyrightClearanceCenter.ViolationsareliabletoprosecutionundertherespectiveCopyrightLaw. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publicationdoesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexempt fromtherelevantprotectivelawsandregulationsandthereforefreeforgeneraluse. While the advice and information in this book are believed to be true and accurate at the date of publication,neithertheauthorsnortheeditorsnorthepublishercanacceptanylegalresponsibilityfor anyerrorsoromissionsthatmaybemade.Thepublishermakesnowarranty,expressorimplied,with respecttothematerialcontainedherein. Printedonacid-freepaper SpringerispartofSpringerScience+BusinessMedia(www.springer.com) To our families Preface Large-scale complex systems, such as modern industrial processes, biological systems,andsocialnetworks,areinterconnectedbydifferentunitsorelements;the system behavior is determined by the inter-relationship between every pair of the elements as well as the local dynamics within each element. It is essential to identify such inter-relationship, namely connectivity and causality, in order to analyze influence mechanisms, structural properties, and overall dynamic behavior. In the control and automation community, connectivity and causality play a vital role in modeling and analysis, especially for fault detection and hazard analysis,becauseanabnormalitycaneasilypropagatewithinandbetweenprocess units due to material and information flow paths. Thus the problem of fault detectionandisolationforindustrialprocessesisconcernedwithdeterminationof root causes and fault propagation. Connectivity and causality, as the key features of process description, can be captured in two ways: 1. From process knowledge: Structural modeling based on first principles structural models can be merged with adjacency/reachability matrices or topology models obtained from process flow-sheets described in standard formats. 2. From process data: Cross-correlation analysis, Granger causality and its extensions, frequency domain methods, information-theoretic methods, and Bayesian networks can be used to identify pairwise relationship and network topology. Thesemethodsrelyonthenotionofinformationfusion,wherebyvarioustypes ofprocessoperatingdataarecombinedwithqualitativeprocessknowledgetogive a holistic picture of the system. Inthisbook,weshallgiveanexhaustiveoverviewofconceptsanddescriptions ofconnectivityandcausalityincomplexprocessesandatutorialguidetoclassical and recent research results on detection of connectivity and causality illustrated withexampleapplications.Astudyofthefusionofdifferentinformationresources for obtaining an acceptable process topology is also introduced. vii viii Preface Some details are omitted in this book due to space constraints. Interested readers should refer to the related literature. For questions, comments, and suggestions, please write to Fan Yang at [email protected]. December 2013 Fan Yang Ping Duan Sirish L. Shah Tongwen Chen Acknowledgments This book would not have been possible without the help from many people. Fan Yang expresses his sincere thanks to Prof. Deyun Xiao at Tsinghua University (Beijing, China) for his long-term guidance and help. Fan Yang’s student,Mr.CenGuo,kindlyhelpedineditingsomepartofthedraft.FanYangis grateful for financial support from the National Natural Science Foundation of China (No. 60904044), the National High-tech R&D Program of China (No.2013AA040702)andtheFoundationofKeyLaboratoryofAdvancedProcess Control for Light Industry (Jiangnan University), Ministry of Education, China. PingDuanisthankfultoProf.NinaF.ThornhillfromImperialCollegeLondon, UK, for comments and suggestions on her research work on direct causality analysis, and to Dr. Yuri Shardt for help with the three-tank experiment. Sirish L. Shah thanks his students, research fellows, and his grandchildren (Maya, Keshav, Anuva, and Avni), all of whom have been the main sources or CAUSES of his enriched life. TongwenChenthankshispastpost-doctoralfellowsandgraduatestudentswho collaborated on related research topics on advanced alarm monitoring, including Iman Izadi, Jiandong Wang, Yue Cheng, Naseeb Adnan, Kabir Ahmed, and Md Shahedul Amin. Tongwen Chen’s research in this area was supported by a strategic project grant from the Natural Sciences and Engineering Research CouncilofCanadaentitled‘‘DevelopmentofanAdvancedTechnologyforAlarm Analysis and Design’’ (2009–2012). AcknowledgmentisgiventotheInstituteofElectricalandElectronicEngineers (IEEE) to reproduce material from the following papers: (cid:2)2013IEEE.Reprinted,withpermission,fromDuanP,YangF,ChenT,ShahSL (2013) Direct causality detection via the transfer entropy approach. IEEE Transactions on Control Systems Technology, 21(6):2052–2066 (as related to material in Chap. 5) (cid:2)2009 IEEE. Reprinted, with permission, from Yang F, Shah SL, Xiao D (2009) SDG model-based analysis of fault propagation in control systems. In: Proc. 2009 Canadian Conference on Electrical and Computer Engineering, St John’s, NL, Canada, pp 1152–1157 (as related to material in Chap. 4) ix x Acknowledgments Acknowledgment is given to International Federation of Automatic Control (IFAC) to reproduce material from the following paper: (cid:2)2010 IFAC. Originally published in IFAC-PapersOnLine. Reprinted, with per- mission, from Yang F, Shah SL, Xiao D (2010) signed directed graph (SDG)- based process description and fault propagation analysis for a tailings pumping process.In:Proceedingsof13thSymposiumonAutomationinMining,Mineral and Metal Processing, Cape Town, South Africa, pp 50–55 (as related to material in Chap. 6) AcknowledgmentisgiventoElseviertoreproducematerialfromthefollowing paper: (cid:2)2006 Elsevier. Reprinted, with permission, from Yim SY, Ananthakumar HG, Benabbas L, Horch A, Drath R, Thornhill N (2006) Using process topology in plant-wide control loop performance assessment. Computers and Chemical Engineering, 31(2):86–99 (Fig. 4.1 in Chap. 4) Acknowledgment is given to University of Zielona Góra and Lubuskie Scientific Society to reproduce material from the following paper: (cid:2)2011 University of Zielona Góra and Lubuskie Scientific Society. Reprinted, with permission, from Yang F, Shah SL, Xiao D (2011) Signed directed graph- based modeling and its validation from process knowledge and process data. International Journal of Applied Mathematics and Computer Science, 22(1):41–53 (as related to material in Chaps. 5 and 6) Contents 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1 Concept of Causality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.2 Connectivity, Correlation, and Causality. . . . . . . . . . . . . . . . . . 4 1.3 Preview of Chapters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.4 Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2 Examples of Applications for Connectivity and Causality Analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.1 Topology Modeling and Closed-Loop Identification . . . . . . . . . 7 2.2 Root Cause Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.3 Risk Analysis: HAZOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.4 Consequential Alarm Identification . . . . . . . . . . . . . . . . . . . . . 9 2.5 Plant-Wide Control Structure Design. . . . . . . . . . . . . . . . . . . . 10 2.6 Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3 Description of Connectivity and Causality. . . . . . . . . . . . . . . . . . . 13 3.1 Description of Connectivity . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.1.1 Adjacency Matrices. . . . . . . . . . . . . . . . . . . . . . . . . . . 14 3.1.2 Digraphs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 3.1.3 Semantic Web Description. . . . . . . . . . . . . . . . . . . . . . 16 3.2 Description of Causality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3.2.1 Structural Equation Models . . . . . . . . . . . . . . . . . . . . . 18 3.2.2 Matrices and Digraphs. . . . . . . . . . . . . . . . . . . . . . . . . 20 3.2.3 Matrix Layout Plots . . . . . . . . . . . . . . . . . . . . . . . . . . 21 3.3 Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 xi