Evaluation of alternative maintenance strategies on a complex system in thermal power systems
dc.authorid | 0000-0002-3835-7684 | |
dc.contributor.advisor | Özgür Ünlüakın, Demet | en_US |
dc.contributor.author | Türkali, Busenur | en_US |
dc.contributor.other | Işık Üniversitesi, Fen Bilimleri Enstitüsü, Endüstri Mühendisliği - Yöneylem Araştırması Yüksek Lisans Programı | en_US |
dc.date.accessioned | 2020-11-26T14:06:37Z | |
dc.date.available | 2020-11-26T14:06:37Z | |
dc.date.issued | 2020-08-12 | |
dc.department | Işık Üniversitesi, Fen Bilimleri Enstitüsü, Endüstri Mühendisliği - Yöneylem Araştırması Yüksek Lisans Programı | en_US |
dc.description | Text in English ; Abstract: English and Turkish | en_US |
dc.description | Includes bibliographical references (leaves 100-108) | en_US |
dc.description | xv, 108 leaves | en_US |
dc.description.abstract | In recent years, due to the continuous development of the industry and the rapid increase in the system complexity, maintenance policies have become more important. Unplanned downtimes due to unexpected failures may lead to huge problems in almost all industry branch. However, carrying out maintenance more than the required to prevent unexpected failures increases maintenance cost signicantly. Thus, balancing the number of reactive and proactive maintenance is very important. The aim of this thesis is to develop maintenance methods under the reactive, condition-based and proactive maintenance strategies using dynamic Bayesian networks (DBNs) in thermal power plants. DBNs which are are probabilistic graphical models, are selected to model the system because they are very effective to formulate the stochastic and structural dependencies between the components. In this study, we evaluate alternative maintenance strategies on a complex systembased on two factors: total number of maintenance and total maintenance cost in a given planning horizon. The proposed maintenance methods are simulated on a multi-component thermal power plant system which has a very complex structure with hidden components among which there are stochastic and structural dependencies. Scenarios are designed considering the maintenance dependability of parallel systems during proactive activities and different reactive cost structures. As a result, performances of all proposed maintenance strategies and methods are compared and analysed under each scenario and the most promising ones are highlighted. | en_US |
dc.description.abstract | Son yıllarda, endüstrinin sürekli gelişimi ve sistemlerin karmaşıklığının artması ile bakım politikaları daha önemli hale gelmiştir. Beklenmedik arızalar nedeniyle ortaya çıkan planlanmayan arıza süreleri, hemen hemen tüm endüstri kollarında büyük sorunlara yol açabilir. Ancak, beklenmedik arızaları önlemek için gereğinden fazla bakım yapılması da bakım maliyetlerini önemli ölçüde artırır. Bu nedenle, reaktif ve proaktif bakım sayısının dengelenmesi çok önemlidir. Bu tezin amacı, termik santrallerde olasılıklı grafik modeller olan dinamik Bayes ağlarını (DBN'ler) kullanarak reaktif, koşul bazlı ve proaktif bakım stratejileri kapsamında bakım yöntemleri geliştirmektir. Sistemi modellemek için bileşenler arasındaki yapısal ve stokastik bağımlılıkları formüle etmek için çok etkili olan DBN'ler seçilmiştir. Bu çalışmada, karmaşık bir sistemde alternatif bakım stratejileri iki faktöre dayanılarak değerlendirilmiştir: belirli bir planlama ufkunda toplam bakım sayısı ve toplam bakım maliyeti. Önerilen bakım yöntemleri, aralarında rassal ve yapısal bağımlılıklar olan gizli bileşenlerin bulunduğu çok karmaşık yapıya sahip çok bileşenli bir termik santral sisteminde simüle edilmiştir. Paralel sistemlerin bakım bağımlılıkları ve farklı reaktif bakım maliyetleri dikkate alınarak senaryolar oluşturulmuştur. Sonuç olarak, önerilen tüm bakım stratejilerinin ve yöntemlerinin performansları her senaryo altında karşılaştırılmış ve analiz edilmiş, en iyi bulunan yöntemler açıklanmıştır. | en_US |
dc.description.tableofcontents | Classification of Maintenance Philosophies | en_US |
dc.description.tableofcontents | Reactive Maintenance Strategies | en_US |
dc.description.tableofcontents | Proactive Maintenance Strategies | en_US |
dc.description.tableofcontents | Preventive Maintenance Strategies | en_US |
dc.description.tableofcontents | Predictive Maintenance Strategies | en_US |
dc.description.tableofcontents | Dependencies in Multi-Component Systems | en_US |
dc.description.tableofcontents | Structural Dependency | en_US |
dc.description.tableofcontents | Economic Dependency | en_US |
dc.description.tableofcontents | Stochastic Dependency | en_US |
dc.description.tableofcontents | Resource Dependency | en_US |
dc.description.tableofcontents | Methods for Modeling the Dependencies | en_US |
dc.description.tableofcontents | Evolution of Dynamic Bayesian Networks | en_US |
dc.description.tableofcontents | Applications of DBNs in Maintenance and Related Fields | en_US |
dc.description.tableofcontents | Maintenance in Complex Systems | en_US |
dc.description.tableofcontents | Maintenance in Thermal Power Plants | en_US |
dc.description.tableofcontents | Methodology and Solution Approach | en_US |
dc.description.tableofcontents | Probabilistic Graphical Models | en_US |
dc.description.tableofcontents | Bayesian Networks and Their Usage in Dependent Systems | en_US |
dc.description.tableofcontents | Dynamic Bayesian Networks in Dependent Systems | en_US |
dc.description.tableofcontents | Reactive Maintenance Strategy | en_US |
dc.description.tableofcontents | General Flow of Reactive Maintenance | en_US |
dc.description.tableofcontents | Failure Effect Myopic Methods (FEMfp, FEMwp) | en_US |
dc.description.tableofcontents | Failure Effect Look-Ahead Methods (FELfp, FELwp) | en_US |
dc.description.tableofcontents | Replacement Effect Myopic Methods (REMfp, REMwp) | en_US |
dc.description.tableofcontents | Replacement Effect Look-Ahead Methods (RELfp, RELwp) | en_US |
dc.description.tableofcontents | Brief Summary of the Proposed Methods | en_US |
dc.description.tableofcontents | Normalization Procedure | en_US |
dc.description.tableofcontents | Proactive Maintenance Strategy | en_US |
dc.description.tableofcontents | Tabu Procedure | en_US |
dc.description.tableofcontents | Constant Interval Proactive Maintenance (CIPM) | en_US |
dc.description.tableofcontents | Dynamic Interval Proactive Maintenance (DIPM) | en_US |
dc.description.tableofcontents | Threshold Based Proactive Maintenance (ThPM) | en_US |
dc.description.tableofcontents | Generic Algorithm of the Proactive Maintenance Strategies | en_US |
dc.description.tableofcontents | A Case Study: The Regenerative Air Heater System in Thermal Power Plants | en_US |
dc.description.tableofcontents | A Thermal Power Plant | en_US |
dc.description.tableofcontents | Air-Gas System in a Thermal Power Plant | en_US |
dc.description.tableofcontents | The Regenerative Air Heater System | en_US |
dc.description.tableofcontents | DBN Modeling of the RAH System | en_US |
dc.description.tableofcontents | Variables and Their States | en_US |
dc.description.tableofcontents | System Relationships | en_US |
dc.description.tableofcontents | Probability Structure | en_US |
dc.description.tableofcontents | Cost Structure | en_US |
dc.description.tableofcontents | Computational Results and Evaluations | en_US |
dc.description.tableofcontents | Results of Reactive Maintenance Modeling | en_US |
dc.description.tableofcontents | Replication Results Regarding to Total Maintenance Number | en_US |
dc.description.tableofcontents | Comparison Results of the Proposed Methods | en_US |
dc.description.tableofcontents | Maintenance Supply Planning of Components | en_US |
dc.description.tableofcontents | Replication Results Regarding to Total Maintenance Cost | en_US |
dc.description.tableofcontents | Justification of the Normalization Procedure | en_US |
dc.description.tableofcontents | Replication Results with Normalization Procedure | en_US |
dc.description.tableofcontents | Sensitivity Analysis of the Proposed Methods according to Hourly Downtime Cost | en_US |
dc.description.tableofcontents | Trade-off Analysis: Maintenance Cost vs Maintenance Number | en_US |
dc.description.tableofcontents | Analysis of Number - Based and Cost – Based Methods at Component Level | en_US |
dc.description.tableofcontents | Results of Proactive Maintenance Modeling | en_US |
dc.description.tableofcontents | Scenarios Based on Independent Parallel Engine Groups | en_US |
dc.description.tableofcontents | Scenario DCR25 | en_US |
dc.description.tableofcontents | Scenario DCR50 | en_US |
dc.description.tableofcontents | Scenario DCR50 - 2*AD | en_US |
dc.description.tableofcontents | Scenarios Based on Dependent Parallel Engine Groups | en_US |
dc.description.tableofcontents | Scenario depDCR25 | en_US |
dc.description.tableofcontents | Scenario depDCR50 | en_US |
dc.description.tableofcontents | Scenario depDCR50-2*AD | en_US |
dc.description.tableofcontents | Comparison of the Strategies using the Best Parameters | en_US |
dc.description.tableofcontents | Justification of Using Tabu Procedure | en_US |
dc.description.tableofcontents | Number and Cost Distribution of the Components | en_US |
dc.description.tableofcontents | Initial probabilities of the RAH DBN model | en_US |
dc.description.tableofcontents | Transition probabilities of the RAH DBN model | en_US |
dc.description.tableofcontents | Conditional probabilities of the RAH DBN model | en_US |
dc.identifier.citation | Türkali, B. (2020). Evaluation of alternative maintenance strategies on a complex system in thermal power systems. İstanbul: Işık Üniversitesi Fen Bilimleri Enstitüsü. | en_US |
dc.identifier.uri | https://hdl.handle.net/11729/2970 | |
dc.institutionauthor | Türkali, Busenur | en_US |
dc.institutionauthorid | 0000-0002-3835-7684 | |
dc.language.iso | en | en_US |
dc.publisher | Işık Üniversitesi | en_US |
dc.relation.publicationcategory | Tez | en_US |
dc.rights | info:eu-repo/semantics/openAccess | en_US |
dc.rights | Attribution-NonCommercial-NoDerivs 3.0 United States | * |
dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/3.0/us/ | * |
dc.subject | DBN | en_US |
dc.subject | Reactive maintenance | en_US |
dc.subject | Proactive maintenance | en_US |
dc.subject | Complex systems | en_US |
dc.subject | Dinamik Bayesçi ağlar | en_US |
dc.subject | Düzeltici bakım | en_US |
dc.subject | Proaktif bakım | en_US |
dc.subject | Kompleks sistemler | en_US |
dc.subject.lcc | TS192 .T87 2020 | |
dc.subject.lcsh | Industrial equipment -- Maintenance and repair | en_US |
dc.subject.lcsh | Reactive maintenance | en_US |
dc.subject.lcsh | Proactive maintenance | en_US |
dc.subject.lcsh | Complex systems | en_US |
dc.subject.lcsh | DBN | en_US |
dc.subject.lcsh | Power-plants -- Maintenance and repair | en_US |
dc.title | Evaluation of alternative maintenance strategies on a complex system in thermal power systems | en_US |
dc.title.alternative | Termik santrallerde kullanılan karmaşık bir sistem üzerinde alternatif bakım stratejilerinin değerlendirilmesi | en_US |
dc.type | Master Thesis | en_US |
dspace.entity.type | Publication |