Abstract— Query expansion is the process of supplementing additional terms to the original query to improve the information retrieval (IR) performance. For heavily inflectional languages such as Arabic, query expansion is considered a difficult task. In this paper, the well-known approach: "The similarity thesaurus" is adopted to be applied on Arabic. Prior to applying this approach, first; datasets (three collections of Arabic documents) are pre-processed to create documents inverted index vocabularies, then, the normal indexing process is carried out. The thesaurus method is applied to create a modified (expanded) query of the original one and the target collection is indexed once more. To gauge the enhancement of retrieval process, the results of normal indexing and those of applying thesaurus approach are evaluated against each other using precision and recall measures. The results have shown that the thesaurus method has considerably enhanced the performance of the Arabic Information Retrieval (AIR) System. As the number of expansion terms increases up to a certain extent (35 terms), the performance has been improved. On the other hand, the performance will not be affected, or grow insignificantly as the number of expansion terms exceeds this limit.

Due to the increase in the number of failures in the wind turbine generators, the condition monitoring system plays a significant role in overcoming the negative effects resulting from the difficult operation conditions. Mechanical and electrical properties can be combined to detect the faults coming from wind turbine generators by analyzing their behavior under different (normal and abnormal) operation conditions. Studying the trend and effect of the electrical torque pulsations on wind turbine generators under different conditions allows for a proper condition monitoring. In this paper, different methodology has been adopted to develop a proper condition monitoring system on the wind generators by evaluating the generator electrical torque based on mechanical torque and taking into account the acceleration torque, which has not been considered in previous work. Using the electric torque with respect to the rotor angular speed of the generator, when it is running under different operation conditions, indicates the generator health, which is the main methodology of the proposed work. A case study, which is based upon collected data from actual measurements, is presented in this work in order to demonstrate the adequacy of the proposed model.

Due to the increase in the failures of the wind generators, Condition Monitoring System (CMS) plays a significant role in overcoming these failures resulting from the harsh operation conditions. The mechanical, thermal, and electrical analyses can be utilized to detect the faults, which are coming from the wind generators by monitoring the changes in their characteristics under different (normal and abnormal) operation conditions. Observing the trend of the electrical torque pulsations of the wind generators under different conditions is beneficial to perform proper condition monitoring. In this paper, different methodology has been adopted to implement a proper condition monitoring system on the wind generators by evaluating the generator electrical torque based on the mechanical and the acceleration torque. Then, in order to specify the generator faults, the trend of the electrical torque with respect to the rotor angular speed of the wind generator under different operation conditions is analyzed. Further, the rate of change in the generator temperature is considered as well as an indicator to define the health of the wind generators with respect to the induced electrical torque, because of the negative effect of the elevated generator temperature on the induced electrical torque. Case study, which is based upon collected data from actual measurements, is presented in this work in order to demonstrate the adequacy of the proposed model.

Purpose – The purpose of this paper is to investigate quality factors that are absolutely essential for successful implementation of total quality management (TQM) in Libyan oil and gas companies (LOGCs). Design/methodology/approach – In all, 11 quality factors with 42 elements were identified to develop a questionnaire to carry out the survey in order to identify the quality factors that are seen by LOGCs to be critical to the success of TQM implementation. In total, 45 questionnaires were provided by hand to quality-related managers from the Libyan oil and gas sector. A total of 42 were returned sufficiently completed, that gave us a response rate of approximately 93.33 per cent. Findings – The empirical analysis demonstrates several key findings: the analysis indicated that 24 quality factors are found to be critical and absolutely essential for successful TQM implementation. These factors classify into three levels of criticality. All of the factors were found to be supported by similar studies and cited literatures. Research limitations/implications – The research is subject to the normal limitations of survey research. The study is using perceptual data provided by quality managers and engineers which may not provide clear picture. It may be suitable to consider gathering information from various stakeholders such as employees, customers, suppliers and even competitors. However, this can be overcome using multiple methods to collect data in future studies. Interestingly, the findings here may be generalisable outside Libya, i.e. South Mediterranean countries. Practical implications – LOGCs should consider TQM as an innovative tool for improving business performance in today’s competitive environment. The findings suggest that the TQM critical success factors should be implemented completely as a whole package rather than on a fragmented basis to get the full potential of the TQM. Originality/value – The study investigate the critical quality factors for successful TQM implementation which will direct an organisation towards business excellence and enhancing success of TQM practices in the oil and gas sector. Very few studies have been performed to investigate and understand this issue. Therefore, the research can make a useful contribution