Multiple Perturbed Collocation Tau Method for Solving Nonlinear Integro-Differential Equations

The purpose of the study was to investigate the numerical solution of non-linear Fredholm and Volterra integro-differential equations by the proposed method called Multiple Perturbed Collocation Tau Method (MPCTM). We assumed a perturbed approximate solution in terms of Chebyshev  polynomial basis function and then determined the derivatives of the perturbed approximate solution which are then substituted into the special classes of the problems considered. Thus, resulting into n-folds integration, the resulting equation is then collocated at equally spaced interior points and the unknown constants in the approximate solution are then obtained by Newton’s method which are then substituted back into the approximate solution.Illustrative examples are given to demonstrate the efficiency, computational cost and accuracy of the method. The results obtained with some numerical examples are compared favorable with some existing numerical methods in literature and with the exact solutions where they are known in closed form.Keywords: Nonlinear Problems, Tau Method, Integro-Differential, Newton’s method

Application of Static Synchronous Compensator (STATCOM) in Improving Power System Performance: A Case Study of The Nigeria 330 KV Electricity Grid

Slow response of the conventional traditional methods for improving power system performance creates the need for adoption of advanced control technologies such as Flexible Alternating Current Transmission System (FACTS) with fast response and low cost for  stabilizing electricity grid power and voltage. In this work, we examined the effect of application of Static Synchronous Compensator (STATCOM), a FACTS controller on the performance of the Nigeria 330 kV, 28-bus power system. The conventional and modified Newton-Raphson-based power flow equations describing the steady state conditions before and after compensation was made to the system were presented. Solutions to the developed equations were obtained using Matlab software (Version 7.9.0.529 ‘R2009b’). The results from the analysis showed that before the application of  STATCOM, five (5) of the twenty eight ( 28) buses of the sample system have their voltage magnitudes fell outside the statutory limit of 0.95 Vi 1.05 p.u, which were improved to 1.0 p.u. each at inclusion of STATCOM. Similarly, the total system active power loss was reduced by 5.88% from 98.21 to 92.44MW.  Evidence from this finding is that STATCOM application on the Nigeria electricity grid will stabilise the system’s voltage and reduce the overall transmission active power loss thereby releasing spare capacities for more consumers.http://dx.doi.org/10.4314/njt.v34i3.2

Nutrition status of children in a well-child clinic in Lagos Nigeria

The burden of malnutrition is evident around the world and more pronounced in developing countries affecting vulnerable groups such as infants, children under five years of age and pregnant women. This study assessed the nutritional status of infants and children aged 9-59 months who visited a well-child clinic at a teaching hospital in Lagos Nigeria. A descriptive cross-sectional study was conducted on 207 children consecutively recruited at a well-child clinic in 2013. Data was collected using structured interviewer-administered questionnaires. Information collected includes the sociodemographic details of each child and caregiver. In addition, selected anthropometric measurements, biochemical tests comprising serum ferritin and total blood protein levels as well as dietary information for each child participant were obtained by trained data collectors. The sampled children were aged 9-59 months, with slightly over half (53.6%) being 12 months old and above. There were more female children and the number of Fathers 84.1%who had attained tertiary education was higher (84.1%) than that of mothers (76.3%). Serum protein and ferritin levels were less than the normal reference values in 1.8% and 26.2% of the children respectively, while the prevalence of underweight children was 4.9% and 8.1% of the children were overweight based on weight-for-age z-scores. Results from the dietary survey showed that the children consumed fewer proteins than carbohydrates. Furthermore, only 18.8% and 12.6% of parents reported feeding their children fruits and vegetables. Significantly more mothers (97.5%) with tertiary education had children with normal weight for age (P<0.05). Despite the low prevalence of malnutrition among the sampled population, it was found that consumption of fruits and vegetables was low, yet these are major sources of vital micronutrients. Results indicated that the prevalence of malnutrition among the study group was generally low. Therefore, steps must be taken to ensure nutrition specific and nutrition sensitive intervention programs aimed at improving the nutritional status of childrenKey words: Nutritional status, assessment, children, weight, ferritin, protein, diet, malnutrition, clini

Agile gravitational search algorithm for cyber-physical path-loss modelling in 5G connected autonomous vehicular network

Based on the characteristics of the 5 G standard defined in Release 17 by 3GPP and that of the emerging Beyond 5 G (or the so-called 6 G) network, cyber-physical systems (CPSs) used in smart transport network infrastructures, such as connected autonomous vehicles (CAV), will significantly depend on the cellular networks. The 5 G and Beyond 5 G (or 6 G) will operate over millimetre-wave (mmWave) bands. These network standards require suitable path loss (PL) models to guarantee effective communication over the network standards of CAV. The existing PL models suffer heavy signal losses and interferences at mmWave bands and may not be suitable for cyber-physical (CP) signal propagation. This paper develops an Agile Gravitational Search Algorithm (AGSA) that mitigates the PL and signal interference problems in the 5G–NR network for CAV. On top of that, a modified Okumura-Hata model (OHM) suitable for deployment in CP terrestrial mobile networks is derived for the CAV-CPS application. These models are tested on the real-world 5 G infrastructure. Results from the simulated models are compared with measured data for the modified, enhanced model and four other existing models. The comparative evaluation shows that the modified OHM and AGSA performed better than existing OHM, COST, and ECC-33 models by 90%. Also, the modified OHM demonstrated reduced signal interference compared to the existing models. In terms of optimisation validation, the AGSA scheme outperforms the Genetic algorithm, Particle Swarm Optimisation, and OHM models by at least 57.43%. On top of that, the enhanced AGSA outperformed existing PL (i.e., Okumura, Egli, Ericson 999, and ECC-33 models) by at least 67%, thus presenting the potential for efficient service provisioning in 5G-NR driverless car applications

Intercalated theophylline-smectite hybrid for pH-mediated delivery

On the basis of their large specific surface areas, high adsorption and cation exchange capacities, swelling potential and low toxicity, natural smectite clays are attractive substrates for the gastric protection of neutral and cationic drugs. Theophylline is an amphoteric xanthine derivative that is widely used as a bronchodilator in the treatment of asthma and chronic obstructive pulmonary disease. This study considers the in vitro uptake and release characteristics of the binary theophylline-smectite system. The cationic form of theophylline was readily ion exchanged into smectite clay at pH 1.2 with a maximum uptake of 67±2 mg g−1. Characterisation of the drug-clay hybrid system by powder X-ray diffraction analysis, Fourier transform infrared spectroscopy, differential scanning calorimetry and scanning electron microscopy confirmed that the theophylline had been exclusively intercalated into the clay system in an amorphous form. The drug remained bound within the clay under simulated gastric conditions at pH 1.2; and the prolonged release of approximately 40% of the drug was observed in simulated intestinal fluid at pH 6.8 and 7.4 within a 2-h timeframe. The incomplete reversibility of the intercalation process was attributed to chemisorption of the drug within the clay lattice. These findings indicate that smectite clay is a potentially suitable vehicle for the safe passage of theophylline into the duodenum. Protection from absorption in the stomach and subsequent prolonged release in the small intestine are advantageous in reducing fluctuations in serum concentration which may impact therapeutic effect and toxicit

Sheep response to sugar cane tops supplemented with varying levels of Leucaena leucocephala foliage

This study was conducted to examine the response of West African Dwarf (WAD) sheep to sugarcane (Sacccharum officinarum) tops supplemented with varying levels of Leucaena leucocephala foliage. Twenty WAD sheep averaging 10.14kg were randomly divided into four groups of 5 replicates, and each group was fed sugarcane tops (SCT) supplemented with varying levels (0%, 25%, 50 and 75%) of Leucaena leucocephala foliage (LLF) in a completely randomized design. Results showed that sugarcane tops (SCT) supplementation with 25% LLF increased (p<0.05) weight gain of sheep. Dry matter intake (DMI) declined with increase in LLF supplementation in the diets. Influence of LLF inclusion in the diets significantly (P<0.05) increased serum biochemical profiles of experimental the animals. The inclusion of llf at 50% and 75% in diets III and IV respectively resulted in higher values serum glutamic oxaloacetic transaminase (93.15iu/l and 109.l0iu/l) and serum glutamicpyruvate transaminase (25.25 and 39.85iu/l). However, supplementation of SCT with LLF at 25% seemed to be best as the animals had highest performance in term of DM1 (530.81 g/day) and weight gain (11.83kg). This can be interpreted to mean that improved animal performance can be achieved in the dry season with the use of grass (sugarcane tops) supplemented with 25% LLF without any deleterious effect on health.Keywords: Sheep, Performance, Nitrogen Utilization, blood, sugarcane tops and LLF

Influence of the phases of menstrual cycle on haemorheologic markers in healthy women

No Abstract. The Tropical Journal of Health Sciences Vol. 12(2) 2005: 6-