Identification of low resistivity layers in the “N” geothermal field using 2D magnetotelluric inversion modelling

Magnetotelluric research in the “N” geothermal field has been carried out to see the subsurface detail in the “N” geothermal field. 2D inversion model is generated by secondary data from magnetotelluric data collection in the form of time series data to become 2D models. Magnetotellurics method is used to identify geothermal system components, especially identifying layers with low resistivity values (2 Ω.m - 10 Ω.m) or also called as the cap rock which is seen with a very contrasting color difference compared to the surrounding layers. There are manifestations on the “N” geothermal field which reinforce the assumption that there is a geothermal system in this area. This research begins by processing time series data to become apparent resistivity and phase data. Time series data processing in this study uses several processing methods to produce better apparent resistivity and phase data. The final result of this study is a 2D model that illustrates the contour of the resistivity value of rocks laterally or vertically. 2D model interpretation in this study identified the cap rock layer with low resistivity distribution (2 Ω.m - 10 Ω.m), the medium resistivity zone identified as the reservoir layer (11 Ω.m - 70 Ω.m), and the resistive zone which has high resistivity value (more than 70 Ω.m)

Performance evaluation and mathematical analysis of direct sequence and frequency hopping spread spectrum systems under wideband interference

This paper presents performance evaluation and comparison analysis of Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS) systems. The evaluation and analysis are done based on the systems performance against wideband interferences. The interferences are signals with similar spectrum characteristic to the transmitted signals of DSSS and FHSS systems. Bit Error Ratio (BER) is used as evaluation parameter to assess the performance of both systems. Simulation and mathematical analysis are performed to test and verify the performance of both systems. Mathematical analysis also verifies that increasing Spreading Frequency on certain conditions will reduce the BER. This research also points out that FHSS system has a better performance compared to DSSS system indicated by smaller BER

Urine analysis sensitivity and specificity for paediatric urinary tract infections

BackgroundPaediatric urinary tract infection (UTI) is one of the most common infections among children and a reliable method for diagnosis is critical for management. Few studies have discussed the relationship between the number of leukocytes in the microscopic urinalysis and urine culture.AimsOur aim was to determine the sensitivity and specificity of pyuria as a predictor of culture- proven UTI in the paediatric age group.MethodsThis retrospective study was conducted between 2015 and 2020 at King Abdulaziz University Hospital. Demographic data, history of congenital anomalies, and microscopic urine analysis of 315 participants (≤ 14 years old) was analysed. Pyuria was defined as > 5 WBC /HPF.ResultsUTI was diagnosed in 115 patients based on urine culture. The most common organism was Escherichia coli. Non-E. coli UTI are more common with vesicoureteral reflux patients. Pyuria was found to be positive in 134 (42.5 per cent) of the total sample; 80 of them had a confirmed UTI, with sensitivity of 70 per cent and specificity of 73 per cent. Nitrite has a high sensitivity (66 per cent) but a low specificity. The association between pyuria and positive urine culture was strongly and independently significant (P=0.001). Pyuria and nitrite positivity appear to be more sensitive to E. coli.ConclusionIn conclusion, pyuria is a strong predictor for urinary tract infection in the paediatric age group and is a wise initial test

Factors Affecting Weight Reduction after Intragastric Balloon Insertion: A Retrospective Study

Background and Objectives: Intragastric balloon (IGB) is a safe option for obesity management. However, studies determining the factors influencing the procedure’s outcomes are scarce. Therefore, our goal was to determine the factors affecting weight reduction after IGB insertion. Materials and Methods: This retrospective study included 126 obese patients who underwent IGB treatment using the ORBERA® Intragastric Balloon System. Patients’ records were retrieved; and demographic data, initial body mass index (BMI), complications, compliance with both diet and exercise programs, and percentage of excess weight reduction were recorded. Results: The study included 108 female (85.7%) and 18 male (14.3%) patients. The mean age was 31.7 ± 8.1 years. The percentage of excess weight loss (EWL) was 55.8 ± 35.7%. The mean weight loss was 13.01 ± 7.51 kg. A significant association was found between EWL and age, initial weight, initial body mass index, and the number of pregnancies. No major complications were observed. However, the balloon had to be removed early in two patients (1.59%) due to its rupture and in two other patients (1.59%) due to severe gastritis. Conclusions: IGB therapy is a safe and effective option for obesity management, associated with low rates of complications. The EWL after IGB insertion is significantly higher among older patients, those with a relatively low initial body mass index, those with a longer duration of IGB insertion, and female patients with less parity. Larger prospective studies are needed to support our results

Laparoscopic management of symptomatic urachus remnants in adults: A retrospective study

Aim: To report our experience in the laparoscopic management of symptomatic urachal remnants (URs) in adults. Patients and Methods: A retrospective study included all patients who underwent laparoscopic excision of URs during the period January 2015–January 2020. The following data were retrieved from the files of the patients: demographic data, clinical presentations, intra-operative findings, the procedure performed, operative details, intraoperative or post-operative complications and follow-up period mentioned in the files for those patients. Results: The study included 10 patients (four males and six females) with a mean age of 27.8 ± 11.0 years. URs were discovered preoperatively in all patients except one patient who was diagnosed intraoperatively. URs were associated with other pathologies in four patients (40%) that required two simultaneous surgical procedures. Eight patients (80%) presented with simple umbilical discharge and were diagnosed easily by ultrasonography. All patients were managed successfully with laparoscopic excision and umbilical sparing technique. Excision of the dome of the bladder was done on the selective approach to one patient. No patients showed early post-operative complications. Only one patient had stitch sinus 6 months postoperatively due to a concomitant hernia repair rather than due to the excision of the URs. Conclusions: Laparoscopic excision of symptomatic urachus is a feasible procedure even when the excision of the bladder is required. It could be performed successfully with other pathologies. It is associated with a low incidence of complications. Laparoscopy allows good visualisation and complete excision that leads to almost no recurrence rate

A study of linear regenerative electromagnetic shock absorber system

The objective of this research paper is to design and develop a linear regenerative electromagnetic shock absorber for automotive suspension system. The significance of the arrangement of magnetic and coil materials as components of the linear regenerative electromagnetic shock absorber is to generate continuous electric energy to deliver power to a vehicles electronics. Different magnets and coil arrangements will be reviewed and analysed. Additionally, a novel design of linear regenerative electromagnetic shock absorbers will be modeled by using the computer aided design software program (SolidWorks®) and tested using apparatus such as a shock absorber dynamometer. The linear regenerative electromagnetic shock absorber system was simulated by using Matlab® and Simulink®. The simulation model was established and validated via experiments. The validated simulation model was then used for the analysis of the system parameter sensitivity. The sensitivity analysis then lead to the design optimization phase which allowed for the harvesting of maximum vibration in the design phase

Performance analysis of a water-drive oil reservoir: An oilfield case study

One of the primary responsibilities of a reservoir engineer is to evaluate the per- formance of hydrocarbon reservoirs to estimate the original hydrocarbons in place, reserves, ultimate oil/gas recovery factor. This responsibility becomes complicated in the case of wa- ter-drive reservoirs due to the high uncertainty associated with aquifer properties, including rock properties and aquifer geometry. This paper presents a new method to find the optimum aquifer model based on the root mean square error (RMSE) values by using MBAL software. The study investigated the transmissibility between the X, Y, and Z reservoirs in the field. Additionally, the original oil-in-place (OOIP) was estimated by using material balance equa- tion and Monte Carlo concepts