A simplified framework and performance analysis for while-drilling telemetry systems in underbalanced drilling operations

As it stands, underbalanced drilling (UBD) operation has been beneficial in the exploration of hydrocarbons and production, with advantages like faster drilling control of lost circulation, stuck pipe situations, minimal or less formation damages and an enhanced ability to expedite development of brown fields. In spite of its edge over conventional drilling, the techniques can be more complex as well. Thus, a telemetry system is required to link downhole and surface while-drilling components transmitting and providing useful information under the real-time condition to the driller during drilling operations for more precise wellbore placement to ensure maximum reservoir exposure, ultimate production increment and monitoring conditions. A novel and systematic decision support system model based on distance-based approach has been developed for performance evaluation and optimal selection of while-drilling telemetry systems for the potential development of a depleted reservoir field. The proposed methodology attests to the need for the relative importance of criteria for a given application, without which inter-criterion comparison could not be accomplished. It requires a set of model selection criteria, along with available telemetry techniques and their level of criteria for optimal selection; and it successfully presents the results in terms of a merit value which is used to rank the while-drilling telemetry systems. This aims at delivering reliable drilling performance resulting to deliverable of real-time downhole data collection and most importantly places the matured well with minimal non-productive time during UBD operations. The scientific value of this study is the development of a simplified user-friendly decision support system for telemetry systems performance evaluation and selection optimization. The proposed framework was being validated and applied to a matured reservoir for an optimum selection of telemetry techniques in the UBD operation. The result of computations displayed similar results obtained by expert judgment demonstrating the significance effect and need for telemetry systems.     

Urban flood vulnerability assessment in a densely urbanized city using multi-factor analysis and machine learning algorithms

Theoretical and Applied Climatology - Flood is considered as the most devastating natural hazards that cause the death of many lives worldwide. The present study aimed to predict flood...