22 research outputs found

    A Genetic Algorithm-based Framework for Soft Handoff Optimization in Wireless Networks

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    In this paper, a genetic algorithm (GA)-based approach is used to evaluate the probability of successful handoff in heterogeneous wireless networks (HWNs) so as to increase capacity and network performance. The traditional handoff schemes are prone to ping pong and corner effects and developing an optimized handoff scheme for seamless, faster, and less power consuming handoff decision is challenging. The GA scheme can effectively optimize soft handoff decision by selecting the best fit network for the mobile terminal (MT) considering quality of service (QoS) requirements, network parameters and user’s preference in terms of cost of different attachment points for the MT. The robustness and ability to determine global optima for any function using crossover and mutation operations makes GA a promising solution. The developed optimization framework was simulated in Matrix Laboratory (MATLAB) software using MATLAB’s optima tool and results show that an optimal MT attachment point is the one with the highest handoff success probability value which determines direction for successful handoff in HWN environment. The system maintained a 90%  with 4 channels and more while a 75% was obtained even at high traffic intensity

    A Machine Learning Framework for Length of Stay Minimization in Healthcare Emergency Department

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    The emergency departments (EDs) in most hospitals, especially in middle-and-low-income countries, need techniques for minimizing the waiting time of patients. The application and utilization of appropriate methods can enhance the number of patients treated, improve patients’ satisfaction, reduce healthcare costs, and lower morbidity and mortality rates which are often associated with poor healthcare facilities, overcrowding, and low availability of healthcare professionals.  Modeling the length of stay (LOS) of patients in healthcare systems is a challenge that must be addressed for sound decision-making regarding capacity planning and resource allocation. This paper presents a machine learning (ML) framework for predicting a patient’s LOS within the ED. A study of the services in the ED of a tertiary healthcare facility in Uyo, Nigeria was conducted to gain insights into its operational procedures and evaluate the impact of certain parameters on LOS. Then, a computer simulation of the system was performed in R programming language using data obtained from records in the hospital. Finally, the performance of four ML classifiers involved in patients’ LOS prediction: Classification and Regression Tree (CART), Random Forest (RF), K-Nearest Neighbour (K-NN), and Support Vector Machine (SVM), were evaluated and results indicate that SVM outperforms others with the highest coefficient of determination (R2) score of 0.986984 and least mean square error (MSE) value of 0.358594. The result demonstrates the capability of ML techniques to effectively assess the performance of healthcare systems and accurately predict patients’ LOS to mitigate the low physician-patient ratio and improve throughput

    Evaluation of Toxicological Effects of Spondias Mombin in Adult Male Wistar Rats

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    Spondias mombin is relied on for various herbal remedies for numerous conditions. This study is to evaluate the acute toxic effect of mombin in adult male Wistar rats. Acute toxicity test was carried out with modified Lorke’s method. Twenty-five male rats weighing between 120-180g were used for the sub-chronic study. The rats were divided into five groups A- E (n=5). Group A served as control. Group B and C received respectively 250mgkg-1 and 500mgkg-1 body weight doses of aqueous leaf extract,  groups D and E received  250mgkg-1 and 500mgkg-1 body weight doses of ethanolic extract. Treatments lasted for twenty eight days. Acute toxicity test carried out showed that leaf extracts of Spondias mombin did not produce mortality in rats.  Significant (p<0.05) reduction in brain and kidney weights was observed in group E treated with 500mgkg-1 of ethanolic extract. Similarly, significant (p<0.05) reduction was observed in spleen weights in groups C and E that were treated with 500mgkg-1 of both extracts. The levels of LDL (p<0.001) and ALP (p<0.05) were significantly reduced.  Alterations in the histology of the liver and kidney of extracts treated groups were observed. Conclusion: This result suggests that although the use of the leaf extracts of Spondias mombin is relatively safe, hepatic and renal toxicity may occur with prolonged use. Keywords: Adverse effects, Mortality, Methods, Complication, Utilizatio

    Path analytic study of factors affecting students’ attitude towards test-taking in secondary schools in Afikpo Education Zone, Ebonyi State, Nigeria

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    A structural equation modelling approach was used to analyse 32 factors affecting students’ attitudes towards test-taking in secondary schools. Data for the study were obtained from a sample of 1,276 students using the proportionate stratified random sampling technique. The instrument used for data collection was a Rating Scale on Factors Affecting Students’ Attitudes Towards Test-Taking (RSFASATTT). Findings of the study revealed a total of 21 factors that significantly affect students’ attitudes towards test-taking in secondary schools. Out of these significant factors, 14 had a positive effect while 7 factors negatively affected students’ attitudes towards test-taking. However, 11 factors were not significant predictors of students’ attitudes towards test-taking. Based on these findings, it was concluded that students’ attitudes towards test-taking are affected by several factors. These factors are either traceable to the students’ emotions, their family background, or the school environment. Based on this conclusion, recommendations and policy implications were made

    Safety of Ionizing Radiation in Selected Conventional X-ray Diagnostic Centres in Calabar and Uyo metropolises, Nigeria

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    Background: Humans are inevitably exposed to background radiation in work and public environments. The aim of this work is to assess the effectiveness of the secondary barriers in conventional x-ray diagnostic centers in Calabar and Uyo metropolises. This is by determining the weekly and annual effective dose in their respective uncontrolled areas and comparing them with the international recommendations. Materials and Methods: This cross-sectional study was conducted in three x-ray diagnostic centers in Calabar, represented as C1, C2, and C3 respectively, and in four xray diagnostic centers in Uyo, represented as U1, U2, U3, and U4 respectively. Background radiation was measured using Radex 1212 A-A battery-powered survey meter, at a distance of 2.5meters away from the xray units. Radiation measurement was taken at three different spots, and the recorded data were analyzed. Results: The mean calculated effective dose per week in mSv/week for each diagnostic center was given as 0.130 ± 0.0068mSv/week. Also, the mean calculated effective dose per year in mSv/year for each center was given as 0.66 ± 0.35mSv/year. These values are below the National Commission on Radiation Protection (NCRP) recommendations of 0.02mSv/week and 1mSv/year respectively. From the results, the mean calculated chance of developing cancer was 2.33 ×10-3% which was lower than the NCRP recommendation for continuous public exposure of 5.5×10-3 %. Conclusion: It could be concluded that the integrity of the shielding designs and their dimensions assessed are safe

    Electric Traction System Technology as a Solution to African Transportation Industries

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    The electric traction system in the case of Africa is highly advantageous in terms of transportation. The electric traction system is designed to provide a DC output source from an AC source of 33kV/230V for suitable mobility of tract devices without minimum frequency change. In this work, electric traction system analysis was obtained using mathematical models and simulation of tracts system components using MATLAB. Due to the application of FACTs devices, a 12-pulse thyristor rectifier is used for rectification. The system components are an energy source, harmonic filter, step-down transformer, rectifier substation, and DC load. The maximum current of total harmonic distortion obtained is certified with the IEEE standard 5% total harmonic distortion. the output voltage is purely stable, and the power factor quality is improved.&nbsp

    Magnetic Resonance Imaging Findings in Patients with Low Back Pains and its Associations with Demographic Variables and Body Mass Index in Onitsha Nigeria

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    Background: Low back pain (LBP) is arguably the most prevalent musculoskeletal condition found among both developed and developing nations. This study was designed to evaluate the MRI findings in patients with LBP and its association with the patients' age, gender, and anthropometric variables in Onitsha, Anambra State, Nigeria. Materials and Methods: This was a retrospective cross-sectional study carried out from June 2021 to August 2021 at the MRI unit of the radiology department of a private diagnostic center in Onitsha Anambra state, Nigeria. A total of 76 MRI reports were selected based on the inclusion criteria of this study, which include reports with LBP clinical indication, radiological findings, and complete patient demographic (age and gender) and anthropometry (weight and height) variables. Results: The majority 42 (53.3%), were males when compared with their female counterparts 34 (44.7%). A greater number, 22(28.9%) of the patients were within the age bracket of 51-60 years, and the least 2(2.6%) were within the age group of 21-30 years. Most 29(38.12%) of the patients had degenerative disc disease, and the least 2(2.63%) had osteoporosis. Conclusion: Male preponderance was noted in this study and majority of the case was seen in people within the sixth decade of life. Degenerative disc disease was the most common pathological entity identified in those presented for MRI due to LBP in our setting. There was a statistically significant mean difference in the MRI findings by age. There was no statistically significant mean difference in the MRI findings by gender

    Effect of ethanolic extracts of Persea Americana seed and zea mays silk on blood glucose levels, body and organ weights of alloxan- induced hyperglycemic Albino wistar rats

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    The effect of ethanolic extracts of Persea americana seed and Zea mays silk on blood glucose levels, body and organ weights of alloxan- induced hyperglycemic Wistar rats was investigated using standard analytical techniques. Thirty male albino rats weighing 120-161g were randomly assigned to six groups of five rats each. Groups 3- 6 were test groups which received 400 mg/kg body weight Persea americana seed single extract, 400 mg/kg body weight Zea mays silk single extract, 400 mg/kg body weight combined extract of Persea americana seed and Zea mays silk and 500 mg/kg body weight combined extract of Persea americana seed and Zea mays silk repectively. Group 1 and 2 served as normal and diabetic controls respectively. Diabetes was induced using 170mg/kg body weight alloxan monohydrate. All the rats received their normal diet and distilled water daily for a period of 28 days. At the end of the experiment, the groups administered 400 mg/kg body weight Zea mays silk single extract and 400 mg/kg body weight combined extract of Persea americana seed and Zea mays silk showed significant (P< 0.05) decrease in fasting blood glucose when compared with the diabetic control. The highest body weight change was observed in the high dose combined extract group followed by the Zea mays silk single extract group. Apart from the kidney and spleen weights, which were significantly reduced in the Zea mays single extract group, there was no significant difference (P> 0.05) in organ weights of the experimental groups compared with the diabetic and normal controls. Persea americana seed increased body and organ weights of experimental animals whereas Zea mays silk decreased same. It may therefore be concluded that Persea americana seed and Zea mays silk are probable hypoglycemic agents.Keywords: Persea americana seed, Zea mays silk, glucose, body weight, organ weigh
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