Root Cause Analysis for software systems is a challenging diagnostic task due to complexity emanating from the interactions between system components. Furthermore, the sheer size of the logged data makes it often difficult for human operators and administrators to perform problem diagnosis and root cause analysis. The diagnostic task is further complicated by the lack of models that could be used to support the diagnostic process. Traditionally, this diagnostic task is conducted by human experts who create mental models of systems, in order to generate hypotheses and conduct the analysis even in the presence of incomplete logged data. A challenge in this area is to provide the necessary concepts, tools, and techniques for the operators to focus their attention to specific parts of the logged data and ultimately to automate the diagnostic process. The work described in this thesis aims at proposing a framework that includes techniques, formalisms, and algorithms aimed at automating the process of root cause analysis. In particular, this work uses annotated requirement goal models to represent the monitored systems' requirements and runtime behavior. The goal models are used in combination with log data to generate a ranked set of diagnostics that represent the combination of tasks that failed leading to the observed failure. In addition, the framework uses a combination of word-based and topic-based information retrieval techniques to reduce the size of log data by filtering out a subset of log data to facilitate the diagnostic process. The process of log data filtering and reduction is based on goal model annotations and generates a sequence of logical literals that represent the possible systems' observations. A second level of investigation consists of looking for evidence for any malicious (i.e., intentionally caused by a third party) activity leading to task failures. This analysis uses annotated anti-goal models that denote possible actions that can be taken by an external user to threaten a given system task. The framework uses a novel probabilistic approach based on Markov Logic Networks. Our experiments show that our approach improves over existing proposals by handling uncertainty in observations, using natively generated log data, and by providing ranked diagnoses. The proposed framework has been evaluated using a test environment based on commercial off-the-shelf software components, publicly available Java Based ATM machine, and the large publicly available dataset (DARPA 2000).

Quality defects are a common problem for producing companies, but causes and consequences are often unknown. The purpose of this thesis assignment is to develop a step-by-step analysis method for identifying the root causes of quality defects based on previously examined consequences. The first steps focus on customer recovery meanwhile the following steps concentrate on process recovery. The analysis method is process-orientated as the complete production and delivery process are scrutinized upstream by the combination of commonly used quality tools.   For testing the applicability of the presented method this thesis comprises a case study conducted at one company receiving complaints about quality defects. For the Case Study Company the consequences and causes of quality defects are described, analyzed and suggestions for improvement are developed.   In the investigated case, the developed method helps to identify causes and consequences of incomplete delivery, the company’s major quality problem. The upstream approach proved advantages for two reasons. First of all including the customer side guarantees that the cause analysis is limited to the relevant problems. With the help of the method the severity of consequences depending on the customers’ awareness of defects and available time can be detected. Secondly problems can be scrutinized in natural order as difficulties in production once identified can be followed step by step to the causes in a preceding step. The main causes identified in this case study are a lack of process definition and of standardization. Thus, the portrayed case suggests that regular appearances of quality defects are not a coincidence. The reasons are the underlying, possibly insufficiently defined and managed processes.   The general finding of the thesis assignment is the presented analysis method that comprises a systematic process-oriented approach designed to examine consequences and causes of quality defects. In contrast to the root cause analysis approaches found in literature each analysis step is described in detail. This makes the method easy to apply in practice. Therefore the method is a valid tool to deal with a high degree of complexity. The case study proved that it is effective and efficient to scrutinize problems with these characteristics. Under different circumstances the application of single quality tools might be sufficient and hence resource effective. Further investigation is necessary since this method has only been tested in one case study.

This thesis investigates issues like maintenance problems, key factors, maintenance challenges, maintenance solutions and practical difficulties in wind energy. In this case, surveys and interviews have been taken from several companies and maintenance experts, to find most prevailing problems and problem-solving methods since last few years. It helps to show, how the energy maintenance has been developed in past few years. Also it analyses the impact of fourth generation maintenance in wind energy production. From research questions, key factors involved in wind energy maintenance provides us with valuable suggestions to develop the maintenance methods in future vision.

Root Cause Analysis for software systems is a challenging diagnostic task due to complexity emanating from the interactions between system components. Furthermore, the sheer size of the logged data makes it often difficult for human operators and administrators to perform problem diagnosis and root cause analysis. The diagnostic task is further complicated by the lack of models that could be used to support the diagnostic process. Traditionally, this diagnostic task is conducted by human experts who create mental models of systems, in order to generate hypotheses and conduct the analysis even in the presence of incomplete logged data. A challenge in this area is to provide the necessary concepts, tools, and techniques for the operators to focus their attention to specific parts of the logged data and ultimately to automate the diagnostic process. The work described in this thesis aims at proposing a framework that includes techniques, formalisms, and algorithms aimed at automating the process of root cause analysis. In particular, this work uses annotated requirement goal models to represent the monitored systems' requirements and runtime behavior. The goal models are used in combination with log data to generate a ranked set of diagnostics that represent the combination of tasks that failed leading to the observed failure. In addition, the framework uses a combination of word-based and topic-based information retrieval techniques to reduce the size of log data by filtering out a subset of log data to facilitate the diagnostic process. The process of log data filtering and reduction is based on goal model annotations and generates a sequence of logical literals that represent the possible systems' observations. A second level of investigation consists of looking for evidence for any malicious (i.e., intentionally caused by a third party) activity leading to task failures. This analysis uses annotated anti-goal models that denote possible actions that can be taken by an external user to threaten a given system task. The framework uses a novel probabilistic approach based on Markov Logic Networks. Our experiments show that our approach improves over existing proposals by handling uncertainty in observations, using natively generated log data, and by providing ranked diagnoses. The proposed framework has been evaluated using a test environment based on commercial off-the-shelf software components, publicly available Java Based ATM machine, and the large publicly available dataset (DARPA 2000).

Atualmente, o ambiente extremamente dinâmico e altamente competitivo, no qual as organizações estão inseridas, aumentou expressivamente a importância da Tecnologia da Informação (TI). Aliada a isto, a crescente complexidade das infraestruturas de redes e serviços, também conhecidas como infraestruturas de TI, tornaram a Gerência de Serviços de Tecnologia da Informação indispensável a qualquer organização. Nesse cenário, coletâneas de boas práticas e processos foram desenvolvidas visando a obter o melhor desempenho dos produtos e serviços oferecidos. Entre as coletâneas amplamente aceitas, tanto na academia quanto na indústria, vale destacar a Biblioteca de Infraestrutura de Tecnologia da Informação (i.e., Information Technology Infrastructure Library, ITIL). Dentre os processos descritos na ITIL, o Gerenciamento de Mudanças é de suma importância para as organizações. Tal processo é responsável por padronizar o planejamento, o agendamento, a implementação e a avaliação de mudanças no ambiente de TI. Ainda que a adoção das boas práticas proporcione significativas melhorias, a ocorrência de falhas em procedimentos de mudanças não pode ser negligenciada. Para tratar eventuais falhas é proposto o processo de Gerenciamento de Problemas, o qual é responsável por gerir o ciclo de vida de problemas. Nesse contexto, o reúso do conhecimento e da experiência do operador, sobre os processos de TI, é de fundamental importância, pois possibilita a simplificação de procedimentos para a detecção da causa raiz de falhas e, consequentemente, minimiza perdas financeiras e custos de manutenção. Apesar disso, nas soluções existentes o processo de diagnóstico é realizado de uma forma estática e ad hoc, o que dificulta reutilizar o conhecimento em falhas recorrentes ou similares. Diante do exposto, nesta dissertação é proposta uma solução para a identificação interativa da causa raiz de problemas detectados em mudanças. Em contraste com as soluções existentes, o foco desta dissertação é o reúso de traços históricos de diagnósticos e da experiência do operador. A solução proposta teve sua aplicabilidade avaliada em dois estudos de casos. Os cenários utilizados são baseados em situações reais, bem como consideram falhas recorrentes em mudanças sobre as infraestruturas de redes e serviços. Os resultados demonstram a capacidade da solução em reutilizar o conhecimento adquirido com experiências anteriores, bem como, na adaptabilidade do diagnóstico gerado, tanto na infraestrutura de TI na qual a falha ocorre, quanto nas respostas fornecidas pelo operador. A estrutura modular da solução desenvolvida permite dividir a complexidade do processo de identificação em problemas menores que podem ser resolvidos individualmente. Assim, as organizações podem personalizar partes da solução para melhor refletirem as necessidades específicas do seu ambiente de TI. / Presently, the extremely dynamic and highly competitive environment, in which organizations are inserted, significantly increased the importance of Information Technology (IT). In addition, the increasing complexity of network infrastructures and services, also known as IT infrastructures, turned the Information Technology Service Management essential to any organization. In this context, guides of best practices and processes were developed to obtain a best performance out of provided products and services. Among the most widely accepted proposals, in both academy and industry, it is worth mentioning the ITIL (Information Technology Infrastructure Library). From the processes described in ITIL, Change Management is indispensable for organizations. This process defines how changes should be planned, scheduled, implemented, and evaluated in IT environments. Despite the significant improvements that the adoption of ITIL’s best practices can provide, the occurrence of failures cannot be neglected. To address possible failures, the process of Problem Management is proposed. Such process is responsible for managing the life cycle of problems. Thus, the reuse of operator’s knowledge and experience, on IT processes, has fundamental importance for allowing to simplify the procedures of detecting failures’ root cause and, therefore, minimizes financial losses and maintenance costs. Nevertheless, the diagnostic process, in the existing solutions, is performed in a static and ad hoc fashion, which complicates the reuse of knowledge in recurrent failures or similar. Based on the previous considerations, in this dissertation, we propose a solution for interactive identification of the root cause of problems detected in IT changes. In contrast to existing solutions, the focus of this solution is the reuse of the operator’s experience and the knowledge from cases that have already been completed. The proposed solution had its applicability evaluated in two case studies. The scenarios used are based on real situations, taking into account recurrent failures in changes on IT infrastructures. The results show not only the ability of the solution to reuse the knowledge acquired from previous experiences, but also the adaptability of diagnosis generated in both the IT infrastructure, where failure occurs, and the responses provided by operator. The modular structure of the developed solution allows to divide the complexity of the identification process into smaller problems that can be solved individually. Thus, organizations can customize parts of the solution to better reflect the specific requirements of your IT environment.

Atualmente, o ambiente extremamente dinâmico e altamente competitivo, no qual as organizações estão inseridas, aumentou expressivamente a importância da Tecnologia da Informação (TI). Aliada a isto, a crescente complexidade das infraestruturas de redes e serviços, também conhecidas como infraestruturas de TI, tornaram a Gerência de Serviços de Tecnologia da Informação indispensável a qualquer organização. Nesse cenário, coletâneas de boas práticas e processos foram desenvolvidas visando a obter o melhor desempenho dos produtos e serviços oferecidos. Entre as coletâneas amplamente aceitas, tanto na academia quanto na indústria, vale destacar a Biblioteca de Infraestrutura de Tecnologia da Informação (i.e., Information Technology Infrastructure Library, ITIL). Dentre os processos descritos na ITIL, o Gerenciamento de Mudanças é de suma importância para as organizações. Tal processo é responsável por padronizar o planejamento, o agendamento, a implementação e a avaliação de mudanças no ambiente de TI. Ainda que a adoção das boas práticas proporcione significativas melhorias, a ocorrência de falhas em procedimentos de mudanças não pode ser negligenciada. Para tratar eventuais falhas é proposto o processo de Gerenciamento de Problemas, o qual é responsável por gerir o ciclo de vida de problemas. Nesse contexto, o reúso do conhecimento e da experiência do operador, sobre os processos de TI, é de fundamental importância, pois possibilita a simplificação de procedimentos para a detecção da causa raiz de falhas e, consequentemente, minimiza perdas financeiras e custos de manutenção. Apesar disso, nas soluções existentes o processo de diagnóstico é realizado de uma forma estática e ad hoc, o que dificulta reutilizar o conhecimento em falhas recorrentes ou similares. Diante do exposto, nesta dissertação é proposta uma solução para a identificação interativa da causa raiz de problemas detectados em mudanças. Em contraste com as soluções existentes, o foco desta dissertação é o reúso de traços históricos de diagnósticos e da experiência do operador. A solução proposta teve sua aplicabilidade avaliada em dois estudos de casos. Os cenários utilizados são baseados em situações reais, bem como consideram falhas recorrentes em mudanças sobre as infraestruturas de redes e serviços. Os resultados demonstram a capacidade da solução em reutilizar o conhecimento adquirido com experiências anteriores, bem como, na adaptabilidade do diagnóstico gerado, tanto na infraestrutura de TI na qual a falha ocorre, quanto nas respostas fornecidas pelo operador. A estrutura modular da solução desenvolvida permite dividir a complexidade do processo de identificação em problemas menores que podem ser resolvidos individualmente. Assim, as organizações podem personalizar partes da solução para melhor refletirem as necessidades específicas do seu ambiente de TI. / Presently, the extremely dynamic and highly competitive environment, in which organizations are inserted, significantly increased the importance of Information Technology (IT). In addition, the increasing complexity of network infrastructures and services, also known as IT infrastructures, turned the Information Technology Service Management essential to any organization. In this context, guides of best practices and processes were developed to obtain a best performance out of provided products and services. Among the most widely accepted proposals, in both academy and industry, it is worth mentioning the ITIL (Information Technology Infrastructure Library). From the processes described in ITIL, Change Management is indispensable for organizations. This process defines how changes should be planned, scheduled, implemented, and evaluated in IT environments. Despite the significant improvements that the adoption of ITIL’s best practices can provide, the occurrence of failures cannot be neglected. To address possible failures, the process of Problem Management is proposed. Such process is responsible for managing the life cycle of problems. Thus, the reuse of operator’s knowledge and experience, on IT processes, has fundamental importance for allowing to simplify the procedures of detecting failures’ root cause and, therefore, minimizes financial losses and maintenance costs. Nevertheless, the diagnostic process, in the existing solutions, is performed in a static and ad hoc fashion, which complicates the reuse of knowledge in recurrent failures or similar. Based on the previous considerations, in this dissertation, we propose a solution for interactive identification of the root cause of problems detected in IT changes. In contrast to existing solutions, the focus of this solution is the reuse of the operator’s experience and the knowledge from cases that have already been completed. The proposed solution had its applicability evaluated in two case studies. The scenarios used are based on real situations, taking into account recurrent failures in changes on IT infrastructures. The results show not only the ability of the solution to reuse the knowledge acquired from previous experiences, but also the adaptability of diagnosis generated in both the IT infrastructure, where failure occurs, and the responses provided by operator. The modular structure of the developed solution allows to divide the complexity of the identification process into smaller problems that can be solved individually. Thus, organizations can customize parts of the solution to better reflect the specific requirements of your IT environment.

Atualmente, o ambiente extremamente dinâmico e altamente competitivo, no qual as organizações estão inseridas, aumentou expressivamente a importância da Tecnologia da Informação (TI). Aliada a isto, a crescente complexidade das infraestruturas de redes e serviços, também conhecidas como infraestruturas de TI, tornaram a Gerência de Serviços de Tecnologia da Informação indispensável a qualquer organização. Nesse cenário, coletâneas de boas práticas e processos foram desenvolvidas visando a obter o melhor desempenho dos produtos e serviços oferecidos. Entre as coletâneas amplamente aceitas, tanto na academia quanto na indústria, vale destacar a Biblioteca de Infraestrutura de Tecnologia da Informação (i.e., Information Technology Infrastructure Library, ITIL). Dentre os processos descritos na ITIL, o Gerenciamento de Mudanças é de suma importância para as organizações. Tal processo é responsável por padronizar o planejamento, o agendamento, a implementação e a avaliação de mudanças no ambiente de TI. Ainda que a adoção das boas práticas proporcione significativas melhorias, a ocorrência de falhas em procedimentos de mudanças não pode ser negligenciada. Para tratar eventuais falhas é proposto o processo de Gerenciamento de Problemas, o qual é responsável por gerir o ciclo de vida de problemas. Nesse contexto, o reúso do conhecimento e da experiência do operador, sobre os processos de TI, é de fundamental importância, pois possibilita a simplificação de procedimentos para a detecção da causa raiz de falhas e, consequentemente, minimiza perdas financeiras e custos de manutenção. Apesar disso, nas soluções existentes o processo de diagnóstico é realizado de uma forma estática e ad hoc, o que dificulta reutilizar o conhecimento em falhas recorrentes ou similares. Diante do exposto, nesta dissertação é proposta uma solução para a identificação interativa da causa raiz de problemas detectados em mudanças. Em contraste com as soluções existentes, o foco desta dissertação é o reúso de traços históricos de diagnósticos e da experiência do operador. A solução proposta teve sua aplicabilidade avaliada em dois estudos de casos. Os cenários utilizados são baseados em situações reais, bem como consideram falhas recorrentes em mudanças sobre as infraestruturas de redes e serviços. Os resultados demonstram a capacidade da solução em reutilizar o conhecimento adquirido com experiências anteriores, bem como, na adaptabilidade do diagnóstico gerado, tanto na infraestrutura de TI na qual a falha ocorre, quanto nas respostas fornecidas pelo operador. A estrutura modular da solução desenvolvida permite dividir a complexidade do processo de identificação em problemas menores que podem ser resolvidos individualmente. Assim, as organizações podem personalizar partes da solução para melhor refletirem as necessidades específicas do seu ambiente de TI. / Presently, the extremely dynamic and highly competitive environment, in which organizations are inserted, significantly increased the importance of Information Technology (IT). In addition, the increasing complexity of network infrastructures and services, also known as IT infrastructures, turned the Information Technology Service Management essential to any organization. In this context, guides of best practices and processes were developed to obtain a best performance out of provided products and services. Among the most widely accepted proposals, in both academy and industry, it is worth mentioning the ITIL (Information Technology Infrastructure Library). From the processes described in ITIL, Change Management is indispensable for organizations. This process defines how changes should be planned, scheduled, implemented, and evaluated in IT environments. Despite the significant improvements that the adoption of ITIL’s best practices can provide, the occurrence of failures cannot be neglected. To address possible failures, the process of Problem Management is proposed. Such process is responsible for managing the life cycle of problems. Thus, the reuse of operator’s knowledge and experience, on IT processes, has fundamental importance for allowing to simplify the procedures of detecting failures’ root cause and, therefore, minimizes financial losses and maintenance costs. Nevertheless, the diagnostic process, in the existing solutions, is performed in a static and ad hoc fashion, which complicates the reuse of knowledge in recurrent failures or similar. Based on the previous considerations, in this dissertation, we propose a solution for interactive identification of the root cause of problems detected in IT changes. In contrast to existing solutions, the focus of this solution is the reuse of the operator’s experience and the knowledge from cases that have already been completed. The proposed solution had its applicability evaluated in two case studies. The scenarios used are based on real situations, taking into account recurrent failures in changes on IT infrastructures. The results show not only the ability of the solution to reuse the knowledge acquired from previous experiences, but also the adaptability of diagnosis generated in both the IT infrastructure, where failure occurs, and the responses provided by operator. The modular structure of the developed solution allows to divide the complexity of the identification process into smaller problems that can be solved individually. Thus, organizations can customize parts of the solution to better reflect the specific requirements of your IT environment.

Context. Software re-engineering has been identified as a business critical activity to improve legacy systems in industries. It is the process of understanding existing software and improving it, for modified or improved functionality, better maintainability, configurability, reusability, or other quality goals. However, there is little knowledge to integrate software quality attributes into the re-engineering process. It is essential to resolve quality problems through applying software re-engineering processes. Objectives. In this study we perform an in-depth investigation to identify and resolve quality problems by applying software re-engineering processes. At the end, we created a quality driven re-engineering framework. Methods. At first, we conducted a literature review to get knowledge for building the quality driven re-engineering framework. After that, we performed a case study in Ericsson Company to validate the processes of the framework. At last, we carried out an experiment to prove that the identified quality problems has been resolved. Results. We compared three existing re-engineering frameworks and identified their weaknesses. In order to fix the weaknesses, we created a quality driven re-engineering framework. This framework is used to improve software quality through identifying and resolving root cause problems in legacy systems. Moreover, we validated the framework for one type of legacy system by successfully applying the framework in a real case in Ericsson Company. And also, we proved that the efficiency of a legacy system is improved after executing an experiment in Ericsson Company. Conclusions. We conclude that the quality driven re-engineering framework is applicable, and it can improve efficiency of a legacy system. Moreover, we conclude that there is a need for further empirical validation of the framework in full scale industrial trials.

Context: Removal of wastes is a crucial area in lean software development. It has been found that there was little evidence on root causes of wastes in lean software development. Root causes from the state of practice had not being investigated. Furthermore, relations between wastes were now successfully exposed through root cause identifications process. Objectives: The objective of this study was to perform an in-depth investigation to identify causes which lead to wastes in Lean software development process in the context of medium to large software development. To this end, researcher also identified relationships that exist between wastes. Methods: The researcher conducted Literature review to look for evidence on waste related activities offered in peer-reviewed literature. Furthermore, the author conducted seven semi-structured interviews and used Grounded Theory method for both literature and interview data analysis. Results: The researcher identified three categories of factors of wastes. Namely, Technical, Non-technical and Global software product development. In the technical category, factors relating to different technical aspects to build a product such as required resource issues, solving complexity issues among others were identified. Similarly, factors relating to people knowledge, management issues as well as factors that bothered on communication, coordination and temporal distance were identified as non-technical and global software product development respectively. For all seven kinds of wastes the root causes were identified. / 0046734784551

Primary objective of this thesis is identify the actual causes of the problem in the organization and subsequently create the most appropriate measures for its elimination. In the first part of thesis basic approaches which deal with changes in organizations are introduced. These approaches are Process Management, Reengineering, Six Sigma, Lean management and Root Cause Analysis. Some of the principles and methods introduce especially in the Root Cause Analysis are then applied during suggestions development in the practical part of the thesis. The second part begins with the introduction of the company and the main problem that the company faces is defined. It is thereafter followed by analysis of the current state which uses a detailed rendering of ongoing processes identifies a critical issue. Based on these findings are diagnosed possible real causes which possible individual solutions are formed. After evaluation of individual proposals that solution is selected which leads to the largest increase in efficiency. In conclusion the specifications of the selected solution are created and evaluated its contributions.