Optimal Renewable Resources Mix for Energy Loss Minimization in Distribution Network-Case Study

This paper provides a case-study about an optimal mix of renewable energy sources in Mazoon Electricity Company (MZEC) network in Al Ashkharah-Oman. The system performance is analyzed in terms of voltage profile and power losses for various scenarios after building a power flow model using available network data. To reduce system power losses, candidate locations and their optimal sizes of distributed generation (DG) units are determined using the optimization toolbox offered by MATLAB©. The optimal renewable mix is obtained with the help of HOMER PRO© software

Harmonics Temporal Profile in High-Voltage Networks: Case Study

This chapter presents a case study about harmonics measurements in high-voltage networks. Measurements were conducted at two locations in the main interconnected system (MIS) of Oman. Voltage and current THDs were recorded for a period of 1 week. The power quality analyzer was set to record required data for a period of 1 week, and the observation period for each recorded value is 10 minutes. At the first location, the grid station (132/33) is feeding industrial as well as other customers. The second grid station (220/132/33 kV) is dedicated to large industrial customers including arc furnaces and rolling mills. The power quality analyzer was installed at the 132 kV side of power transformers at both locations. Recorded data are analyzed, and temporal harmonics profiles are studied. A clear temporal variation of harmonics similar to that of aggregate load and local voltage profiles was observed at the grid station feeding mixed residential and industrial loads. However, this correlation between system load and harmonics profile diminishes at the grid station dedicated for heavy industrial loads

EXPLORING THE IMPACTS OF COVID-19 PANDEMIC ON OMAN'S ELECTRICITY SECTOR

This article reviews the recent trends of Oman's electricity sector before the COVID-19 pandemic outbreak. The impacts of the pandemic on the Main Interconnected System (MIS) of Oman were analyzed using hourly load data. The analysis shows that the MIS demand declined as a result of the decrease in economic activities during the lockdown. In addition, the MIS demand experienced temporal and geographical variations: the former is demonstrated by a shift in peak demand hours, while the latter is represented by a reduction in Muscat's urban areas' load compared with those of other areas

Factors pertaining to academic probation of engineering students: A case study

Ensuring normal progression of students isof paramount importance due to its financial implications in a higher education institution. An indicator that reflects how well an institution is doing in this respect is in the number of students on probation. This study was conducted through a survey to determine the underlying factors that lead to academic probation by the students in order to help in recommending remedial measures. As a case study, the survey was carried out on students in the College of Engineering at Sultan Qaboos University (Oman) who were on academic probation by the end of fall semester. This study has revealed that failure in basic science courses is a major contributing factor. Other factors are the students' poor study habits, inability to concentrate and lack of academic advising in some cases. Recommended remedial measures include establishing drop-in centers to provide individual tutoring, and an advising unit in each department. A course on study skills and time management is recommended for all new students.qscienc

Faculty members’ perceptions about the effectiveness of the procedures for applying the appraisal of academic staff at Sultan Qaboos University

The appraisal of academic staff at Sultan Qaboos University (SQU) has been in place for many years as a quality assurance measure. Its primary objective is to enhance staff performance by identifying commendable areas and those requiring improvement in daily activities. Over the years, this appraisal has contributed in faculty development and quality assurance as well as in the continuous improvement. This study explores the perceptions of faculty members at the College of Education concerning the procedures for applying the academic appraisal form at SQU. Utilizing a mixed-method approach (quantitative and qualitative), including questionnaire and semi-structured interview, the research examines the faculty members' views on the effectiveness of the appraisal procedures. The sample participating in this study was 54 faculty members. Out of the 54 participants, 48 completed the questionnaire, while 6 were chosen for in-depth semi-structured interviews. The sample included a wide range of participants to reflect the diversity within the academic staff. The findings may offer valuable insights into the current status of these perceptions and potentially assist policy makers at SQU in enhancing the existing procedures and system for applying the academic appraisal. Furthermore, the results may lead to a set of recommendations and directions for future research, helping to improve the robustness and applicability of the appraisal system within the university context

A novel mutation in HSD11B2 causes apparent mineralocorticoid excess in an Omani kindred

Apparent mineralocorticoid excess (AME) is a rare autosomal recessive genetic disorder causing severe hypertension in childhood due to a deficiency of 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2), which is encoded by HSD11B2. Without treatment, chronic hypertension leads to early development of end-organ damage. Approximately 40 causative mutations in HSD11B2 have been identified in ∼100 AME patients worldwide. We have studied the clinical presentation, biochemical parameters, and molecular genetics in six patients from a consanguineous Omani family with AME. DNA sequence analysis of affected members of this family revealed homozygous c.799A>G mutations within exon 4 of HSD11B2, corresponding to a p.T267A mutation of 11βHSD2. The structural change and predicted consequences owing to the p.T267A mutation have been modeled in silico. We conclude that this novel mutation is responsible for AME in this family

Clinical, genetic, and structural basis of apparent mineralocorticoid excess due to 11β-hydroxysteroid dehydrogenase type 2 deficiency

Mutations in 11β-hydroxysteroid dehydrogenase type 2 gene (HSD11B2) cause an extraordinarily rare autosomal recessive disorder, apparent mineralocorticoid excess (AME). AME is a form of low renin hypertension that is potentially fatal if untreated. Mutations in the HSD11B2 gene result either in severe AME or a milder phenotype (type 2 AME). To date, ∼40 causative mutations have been identified. As part of the International Consortium for Rare Steroid Disorders, we have diagnosed and followed the largest single worldwide cohort of 36 AME patients. Here, we present the genotype and clinical phenotype of these patients, prominently from consanguineous marriages in the Middle East, who display profound hypertension and hypokalemic alkalosis. To correlate mutations with phenotypic severity, we constructed a computational model of the HSD11B2 protein. Having used a similar strategy for the in silico evaluation of 150 mutations of CYP21A2, the disease-causing gene in congenital adrenal hyperplasia, we now provide a full structural explanation for the clinical severity of AME resulting from each known HSD11B2 missense mutation. We find that mutations that allow the formation of an inactive dimer, alter substrate/coenzyme binding, or impair structural stability of HSD11B2 yield severe AME. In contrast, mutations that cause an indirect disruption of substrate binding or mildly alter intramolecular interactions result in type 2 AME. A simple in silico evaluation of novel missense mutations could help predict the often-diverse phenotypes of an extremely rare monogenic disorder

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

The making of rivals and strange bedfellows : patterns of Turkish and Russian security assistance in the Syrian and Libyan civil wars

Published online: 24 February 2023In the Libyan and Syrian civil wars, Russia and Turkey emerged as two principal players providing security assistance to opposing warring parties. While interventions on the part of the two foreign powers have introduced new dynamics into intractable and volatile armed conflicts, the underlying intention was to inject extraneous goals into ongoing conflicts and project power in the southern Mediterranean region. This article investigates security assistance theoretically and empirically. Theoretically, we propose a typology that distinguishes between formal, informal and semi-formal processes of wartime security assistance across the state-non-state dimension. Empirically, drawing on rare access to state officials, former and active rebels, as well as mercenary actors in Syria and Libya, we give a unique description of the patterns of security assistance provided by Russia and Turkey to state and non-state armed actors. We examine the ways in which the two foreign powers have created a nexus between the two conflicts by capitalizing on pre-existing security assistance frameworks in Syria to recruit and deploy fighters to Libya. Although security assistance has emerged as a competition site between Russia and Turkey, we demonstrate how mutual recognition of security interests has created margins for negotiation and agreement-reaching in Syria and Libya