Solution to the economic dispatch problem of the Nigerian power system using genetic algorithm

This paper aims to solve the economic dispatch problem of the 28-bus Nigerian power system using genetic algorithm. The power flow solution of the network is first obtained using Newton-Raphson technique; the solution thus obtained is used to determine the loss coefficients of the network. For this study, a forecasted load demand of 2000MW will be considered, MATLAB's genetic algorithm optimization toolbox is used to obtain the optimum generation level of each unit. The optimal power output of each scheduled generating units was obtained after 200 iterations at a minimal generation cost of ₦136,370.205/hr. A power loss of 11.32MW in the network was also obtained using Kron's loss formula.Keywords: Genetic Algorithm, Economic Dispatch, loss coefficient, Optimization, Constrain

Effects of Short Inter‑Pregnancy Interval on Maternal and Perinatal Outcomes: A Cohort Study of Pregnant Women in a Low‑Income Country

Background: Short inter‑pregnancy interval (IPI) is a potential risk factor for adverse pregnancy outcomes. Previous reports from sub‑Sahara Africa documented increasing incidence of short IPI but evidence is lacking in its effect on pregnancy outcome. Aim: The study aimed to determine the effect of short IPI on pregnancy outcome in Nigeria. Subjects and Methods: It was a prospective cohort study of 271 pregnant women receiving antenatal care in a tertiary hospital in Nigeria. For every eligible woman with short IPI (<18 months) recruited; a suitable control with IPI ≥18 months was selected. Statistical analysis was both inferential and descriptive using the statistical package for social sciences version 24 (SPSS Inc. Chicago, Illinois, USA) for windows. A P value of less than 0.05 was considered statistically significant. Results: Incidence of maternal anemia was higher in women with short IPI than control (RR: 2.091; 95% CI: 1.4433.031; P < 0.001). Other maternal and perinatal outcome measures including premature rupture of membranes, preterm labor/delivery, pregnancy induced hypertension, third  trimester bleeding, postpartum hemorrhage, and inadequate gestational weight gain did not show any significant association with short IPI (P > 0.05). Conclusion: Short IPI is associated with anemia in pregnancy in Nigeria. Public health campaigns for improvement in uptake of family planning  services and breastfeeding may help reduce the incidence of short IPI and anemia in low income countries. Keywords: Nigeria, pregnancy outcome, short inter‑pregnancy interva