Pseudo-Inverse Matrix Model for Estimating Long-Term Annual Peak Electricity Demand: The Covenant University's Experience

One of the major decision problems facing any electrical supply undertaking is the forecasting of peak power demand. A problem therefore arises when an estimate of future electricity demand is not known to prepare for impending possible increase in electricity demand. To overcome this problem, it is therefore imperative to evaluate the precise amount of energy required for a sustainable power supply to customers. In line with this goal, this study established a mathematical model of regression analysis using Pseudo-Inverse Matrix (PIM) method for the assessment of the historical data of Covenant University's electric energy consumption. This method predicts a more accurate and reliable future energy requirement for the community, with special consideration for the next one decade. The accuracy of prediction based on the use of PIM method is compared with the forecast result of the Least Squares Model (LSM), commonly used by engineers in making long-term forecast. The error analysis result from the Mean Absolute Percentage Error (MAPE) and the Root Mean Square Error (RMSE) performed on the two models using Mean Absolute Deviation (MAD) shows that the PIM is the most accurate of the models. Though this method is examined using a University community, it can be further extended to cover the whole country, provided the historical data of the country's past electric energy consumptions is available. Keywords: error analysis, historical data, linear regression, peak demand, pseudo-inverse matrix. JEL Classifications:  C53, L94, Q47 DOI: https://doi.org/10.32479/ijeep.756

Critical Review of Different Methods for Siting and Sizing Distributed-generators

Due to several benefits attached to distributed generators such as reduction in line losses, improved voltage profile, reliable system etc., the study on how to optimally site and size distributed generators has been on the increase for more than two decades. This has propelled several researchers to explore various scientific and engineering powerful simulation tools, valid and reliable scientific methods like analytical, meta-heuristic and hybrid methods to optimally place and size distributed generator(s) for optimal benefits. This study gives a critical review of different methods used in siting and sizing distributed generators alongside their results, test systems and gaps in literature

Prevalence and pattern of cystic kidney diseases in Ilorin, Nigeria

Cystic kidney disease is an important cause of chronic renal failure. Since the utili-zation of imaging techniques in the diagnosis of diseases has become widespread, cystic kidney disease is now being increasingly diagnosed. This study is designed to determine the prevalence and pattern of cystic kidney disease at the Nephrology Unit of University of Ilorin Teaching Hospital (UITH), Ilorin. All consecutive adult patients seen in the Nephrology Unit of UITH during a ten-year period (January 1999-December 2008) were studied for the presence of cystic kidney disease. The results were analyzed with specific reference to age, gender, annual inci-dence, type of cystic disease, location of cyst, mode of presentation, complications and prognosis. A total of 67 out of 436 renal patients (15.4%) studied had cystic kidney disease. A progressive annual increase in the number of cases was noticed. The age-range was 20-83 years with a mean of 47.4 +/- 16.2 years and the peak incidence was in the third and sixth decades with male to female ratio of 1.3:1. The types of cystic kidney disease identified in the study were: 26 simple cysts (38.8%), 35 polycystic kidney disease (53.3%) and six multicystic kidney disease (8.9%). The most common mode of presentation was abdominal pain followed by hypertension, urinary tract infection, chronic renal failure and palpable abdominal mass, in decreasing order. Our study indicates that cystic kidney disease is not an uncommon problem among our renal patients and the incidence is on the increase. Although, routine screening of family members with cystic kidney disease still remains a contentious issue because the knowledge may evoke anxiety in terms of employment and insurance, screening of symptomatic cases or those that develop hypertension, hematuria and proteinuria is strongly recommended

Prevalence of Chronic Kidney Disease in newly diagnosed patients with Human immunodeficiency virus in Ilorin, Nigeria

Abstract Introduction: Human immunodeficiency virus (HIV) the causative agent of Acquired immunodeficiency syndrome (AIDS) is an important cause of renal diseases in sub-Saharan Africa. There is paucity of studies on the burden of chronic kidney disease (CKD) among patients with HIV/AIDS in the North-Central zone of Nigeria. Methods: This is a cross-sectional study of 227 newly-diagnosed, antiretroviral naïve patients with HIV/AIDS seen at the HIV clinic of the Medical Out-patient Department (MOPD) of University of Ilorin Teaching Hospital (UITH). They were matched with 108 control group. Laboratory investigations were performed for the participants. CKD was defined as estimated glomerular filtration rate (eGFR) 30 mg/g. Results: There were 100 (44%) males among the patients and 47 (43.5%) among the control group. The mean ages of the patients and controls were 40.3 ± 10.3 years and 41.8 ± 9.5 years respectively. CKD was observed in 108 (47.6%) among the patients and 18 (16.7%) of the controls (p = 0.01). The median CD4 T-cell count was significantly lower in patients with CKD. Ninety-three (41.0%) of the patients had dipstick proteinuria of > 2 +. The median albumin creatinine ratio (ACR) was significantly higher among the HIV-positive patients (272.3 mg/g) compared with the HIV-negative controls (27.22 mg/g) p = 0.01. The CD4 T-cell count correlates positively with eGFR (r = 0.463, p = 0.001) and negatively with ACR (r = -0.806, p = 0.001). Conclusions: CKD is very common among patients with HIV/AIDS in Ilorin. Screening and early intervention for CKD should be part of the protocols in the management of these patients

Rationale and design of the Newer Versus Older Antihypertensive Agents in African Hypertensive Patients (NOAAH) trial

Abstract Background. Sub-Saharan Africa experiences an epidemic surge in hypertension. Studies in African Americans led to the recommendation to initiate antihypertensive treatment in Blacks with a diuretic or a low-dose fixed combination including a diuretic. We mounted the Newer versus Older Antihypertensive Agents in African Hypertensive Patients (NOAAH) trial to compare in native African patients a fixed combination of newer drugs, not involving a diuretic, with a combination of older drugs including a diuretic. Methods. Patients aged 30-69 years with uncomplicated hypertension (140-179/90-109 mmHg) and two or fewer associated risk factors are eligible. After a 4-week run-in period off treatment, 180 patients will be randomized to once daily bisoprolol/hydrochlorothiazide 5/6.25 mg or amlodipine/valsartan 5/160 mg. To attain and maintain blood pressure below 140/90 mmHg during 6 months of follow-up, the doses of bisoprolol and amlodipine in the combination tablets will be increased to 10 mg/day with the possible addition of α-methyldopa or hydralazine. NOAAH is powered to demonstrate a 5-mmHg between-group difference in sitting systolic pressure with a two-sided p-value of 0.01 and 90% power. NOAAH is investigator-led and complies with the Helsinki declaration. Results. Six centers in four sub-Saharan countries started patient recruitment on September 1, 2010. On December 1, 195 patients were screened, 171 were enrolled, and 51 were randomized and followed up. The trial will be completed in the third quarter of 2011. Conclusions. NOAAH (NCT01030458) is the first randomized multicenter trial of antihypertensive medications in hypertensive patients born and living in sub-Saharan Africa.status: publishe

Microorganisms and food safety risks associated with indigenous fermented foods from Africa

Indigenous fermented foods (IFFs) have a long history in Africa and are embedded in cultural norms and practices. Typically, these foods are produced at a small or household scale using indigenous processing technologies. In addition, limited knowledge of good manufacturing and handling practices can lead to production under unhygienic conditions. This results in variations in the quality and safety attributes of IFFs, as spoilage and pathogenic bacteria can be introduced at any stage of the value chain. These foods have an important role in the African diet and can contribute to food security by increasing the availability of cheap, nutritious food and supporting livelihoods. However, the presence of foodborne pathogens and antibiotic-resistant bacteria in IFFs may constitute a health risk to consumers. Therefore, this review presents an overview of the microorganisms associated with IFFs from Africa, focusing on microbial food safety hazards. African indigenous fermented foods offer a vast genetic potential of undiscovered strains that possess valuable technical characteristics. However, IFFs may also serve as vehicles of pathogenic and antibiotic-resistant bacteria and genetic determinants. Significant research and data gaps exist regarding the microbiological safety of these food products, which warrant urgent attention. We propose practical solutions for improving the safety of African IFFs requiring action and collaboration from all stakeholders, including researchers, producers, governmental regulatory bodies, and consumers