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Item Adherence to iron deficiency interventions among pregnant women attending antenatal clinics in Ubungo municipality, Dar es Salaam, Tanzania(Bulletin of the National Research Centre, 2025-01-22) Glory Benjamin; Ezra J. Mrema; Nchang’wa Nhumba; Albert Burudi Wakoli; Hussein H. MwangaAbstract Background Iron deficiency anemia in pregnant women remains a public health concern despite iron deficiency interventions that have been implemented. This study investigated adherence to iron deficiency interventions and the associated factors among pregnant women attending antenatal clinics in Ubungo Municipality. Methods This cross-sectional study used a systematic random sampling technique to obtain 503 participants from the surveyed clinics. Interviews were conducted by using interviewer-administered questionnaires. Data were analyzed using Stata version 17. The study employed binary and multivariable logistic regression analysis to determine factors associated with adherence to iron deficiency interventions. Results In this study, 72% of participants were non-adherent and 28% were adherent to the interventions. In multivariable regression analysis, participants who forgot to take their iron tables on most days (AOR 2.35; 95% CI 1.23–4.48) and those who reported that not enough time was spent on education and counseling during antenatal clinic visits (AOR 3.87; 95% CI 1.08–13.84) were more likely to be non-adherent to iron deficiency interventions. Conclusions Majority of pregnant women in Ubungo Municipality were non-adherent to iron deficiency interventions. Non-adherence was associated with a tendency to forget taking iron tablets, and lack of enough time in providing health education and counseling. Improving the quality of health education and counseling could increase adherence to iron deficiency interventions and reduce maternal–child morbidity and mortality rates.Item Numerical Study of Shear Banding in Flows of Fluids Governed by the Rolie-Poly Two-Fluid Model via Stabilized Finite Volume Methods(Processes | An Open Access Journal from MDPI, 2020-07-09) Jade Gesare Abuga; Tiri ChinyokaThe flow of viscoelastic fluids may, under certain conditions, exhibit shear-banding characteristics that result fromtheir susceptibility to unusual flowinstabilities. In thiswork, we explore both the existing shear banding mechanisms in the literature, namely; constitutive instabilities and flow-induced inhomogeneities. Shear banding due to constitutive instabilities is modelled via either the Johnson–Segalman or the Giesekus constitutive models. Shear banding due to flow-induced inhomogeneities is modelled via the Rolie–Poly constitutive model. The Rolie–Poly constitutive equation is especially chosen because it expresses, precisely, the shear rheometry of polymer solutions for a large number of strain rates. For the Rolie–Poly approach, we use the two-fluid model wherein the stress dynamics are coupled with concentration equations. We follow a computational analysis approach via an efficient and versatile numerical algorithm. The numerical algorithm is based on the Finite VolumeMethod (FVM) and it is implemented in the open-source software package, OpenFOAM. The efficiency of our numerical algorithms is enhanced via two possible stabilization techniques, namely; the Log-Conformation Reformulation (LCR) and the Discrete Elastic Viscous Stress Splitting (DEVSS) methodologies. We demonstrate that our stabilized numerical algorithms accurately simulate these complex (shear banded) flows of complex (viscoelastic) fluids. Verification of the shear-banding results via both the Giesekus and Johnson-Segalman models show good agreement with existing literature using the DEVSS technique. A comparison of the Rolie–Poly two-fluid model results with existing literature for the concentration and velocity profiles is also in good agreement.Item Mathematical Modelling and Simulation of Aluminium Filling in Conical Pipe and Cylindrical Pipe under High Pressure(Physical Science & Biophysics Journal, 2022-08-10) Abuga JGThe desired technology for manufacturing light-weight components from metal alloys mostly aluminum and magnesium alloy is Die casting. High pressure die casting requires the liquid metal to be forced at high speed and pressure through a metal pipe. In our study, we seek to study Aluminum filling under high pressure in two different pipes, cylindrical and conical pipes. Two cases are considered for the cylindrical pipe, when the pipe vertical and when the pipe in inclined at an angle of 450 with the horizontal. The governing equations are obtained and the results are compared. The governing equations are obtained and modeling is done using ANSYS FLUENT. The results show that inclining the cylindrical pipe causes a shift in the oscillations and the inclined pipe has slightly lower amplitude of oscillation implying a greater loss of energy due to the inclination. The inclined cylindrical pipe has higher damping compared to the vertical cylindrical pipe. It is also evident that the conical pipe has higher oscillations than the cylindrical pipe implying a greater loss of energy for the conical cylindrical.Item FRAUD DETECTION IN BANKING USING MACHINE LEARNING(The European Academic Journal (EAJ), 2024-03-28) Jade Gesare Abuga; Editah Hadassa Abuto; Roy KuriaFinancial institutions, particularly banks, have a challenge of fraud detection. Fraud poses a substantial financial risk to both institutions and their customers since fraudulent activities can result in significant monetary losses and erode customer trust. Recent research has shown that machine learning techniques can be used to detect fraud in the banking sector. In this project, we applied logistic regression, random forest, K-Nearest Neighbours, and decision trees to detect fraudulent transactions to the problem of fraud detection in the banking industry. The dataset was obtained from Kaggle and has 31 variables. Logistic regression had the lowest performance metrics with an accuracy of 87.91% while the decision tree had the highest performance metrics with an accuracy of 97.17%.Item Smart Maternity: Machine Learning for Safer Prenatal Clinic(The European Academic Journal (EAJ), 2024-05) Dr. Jade AbugaMaternal health is a major public health concern because of its far-reaching implications for the well-being of both the mother and the child. Most maternal deaths can be prevented if there is a timely intervention that is offered to the mothers. It is therefore important to be able to predict if a mother is classified as being in high risk, low risk, and mid-risk to enable prompt attention to be given to the mother. In this study, we are using Machine learning to train a maternal data set having seven attributes and divided into three categories, high-risk, mid-risk, and low-risk pregnancies. The main aim of this study is to develop and evaluate machine learning models for predicting maternal risk levels, categorized as high risk, mid-risk, and low risk, based on a dataset containing seven attributes related to maternal health. The method involved training three Machine Learning algorithms, Logistic Regression, Random Forest and Support Vector Machine (SVM) using the dataset. The data had a significant difference in the categories thus, Synthetic Minority Over-sampling Technique (SMOTE) was used to address the class imbalance. Each algorithm was trained and evaluated on both the imbalanced and balanced datasets. To train the model, the data was divided into the training and testing sets split into 80 and 20 percent for the train and test data respectively to evaluate the model’s performance on unseen data. The performance of the algorithms was compared based on their accuracy in predicting maternal risk levels. Additionally, the study assessed the effectiveness of each algorithm in predicting risk levels for randomly entered datasets. The Random Forest achieved the highest accuracy of 85.71 and 81.77 percent for the balanced and imbalanced dataset respectively. Generally, algorithms trained with the smote-balanced dataset performed much better than with the imbalanced dataset. The risk level for a randomly entered dataset was predicted and Random Forest and Support Vector Machine predicted accurately.Item An investigation of the effect of hall current and rotational parameter on dissipative fluid flow past a vertical semi-infinite plate(Journal of Engineering and Technology Research, 2011-10) J. G. Abuga; M. Kinyanjui; J. K. SigeyMagneto hydrodynamics (MHD) stokes problem for a vertical semi-infinite plate in a dissipative rotating fluid with hall current has been considered. The partial differential equations governing the problem are framed and then solved using numerical methods of implicit finite difference approximations. An analysis of effects of parameter on the velocity (both primary and secondary) profiles and temperature distribution profiles are shown graphically and the results are discussed.Item Benchmark solutions of the stabilized computations of flows of fluids governed by the Rolie-Poly constitutive model(J. Phys. Commun., 2020-01) J G Abuga; T Chinyokaecent studies demonstrate that flow induced non-uniformities of concentration can trigger shear banding in the flow of certain viscoelastic fluids. These studies show that the driving mechanisms for such shear banding are related to the coupling of the polymer stresses to an inhomogeneous concentration profile. The Rolie-Poly (RP) viscoelastic constitutive model has been used in such studies since it has been comprehensively subjected to extensive experimental validation with regards to shear banding and has the demonstrated ability to accurately express the rheology of polymer solutions for a wide range of strain rates. The primary aim of this work is to develop an efficient computational methodology that could be used to accurately simulate the flow of complex fluids governed by the Rolie-Poly constitutive equation. The development of such a computational platform is crucially important for the purposes of our follow up studies on the computational analysis of shear banding phenomena by coupling polymer stress with inhomogeneous concentration profile. Our numerical algorithms will be based on the finite volume method (FVM) and will be implemented on the open source software package OpenFOAM®. In this paper, we will present both validation results as well as new benchmark results from our FVM based OpenFOAM® numerical solver for flow of fluids governed by the Rolie-Poly constitutive model. We use two well-known benchmark problems, the lid-driven cavity flow and the 4:1 planar contraction flow problems. In order to stabilize the numerical algorithm at high Weissenberg numbers, we employ either of two stabilization techniques; the Discrete Elastic Viscous Stress Splitting (DEVSS) technique as well as the Log-Conformation Reformulation (LCR) methodology. Validation of our results is done by comparing our (stabilized) numerical results, against data from existing literature. The numerical results obtained for the contraction flow using the LCR stabilization approach are in good agreement with the existing literature for a wider range of Weissenberg numbers. The DEVSS method shows a good agreement only for lower Weissenberg numbers. For the lid-driven cavity flow, good agreement with the existing literature is observed for low Weissenberg numbers using either of the two stabilization techniques.Item Existence of solutions for quasi-linear impulsive functional integrodi erential equations in Banach spaces(J. Nonlinear Sci. Appl., 2014) Francis Paul Samuel; Krishnan BalachandranWe study the existence of mild solutions for quasilinear impulsive integrodi erential equation in Banach spaces. The results are established by using Hausdor 's measure of noncompactness and xed point theorem. Application is provided to illustrate the theory. c 2014 All rights reserved.Item Controllability Results for Impulsive Neutral Functional Evolution Integrodifferential Inclusions with Infinite Delay(European International Journal of Science and Technology, 2013-06) T. Gunasekar; F. Paul Samuel; M. Mallika ArjunanIn this paper controllability of the following impulsive partial neutral functional integrodifferential evolution inclusions with infinite delay in Banach spaces. The approach is used the nonlinear alternative of Leray-Schauder type multivalued maps. An example is also given to illustrate our result.Item Existence Solutions for Quasilinear Evolution Integrodifferential Equations with Infinite Delay(International Journal of Engineering and Technical Research (IJETR), 2014-04) Francis Paul Samuel; Tumaini RukikoLisso; Kayiita Zachary KaundaThe paper is concerned with the existence and uniqueness solution of quasi linear evolution integrodifferential equations with in finite delay in Banach spaces. The results a reobtained by C0-semi group of linear bounded ope rato r and Banach f ix ed point theorem.Item Quasilinear Delay Differential Equations with Nonlocal Conditions via Measures of Non Compactness(International Journal of Mathematics Trends and Technology, 2014-04) Francis Paul SamuelIn this paper, we study the existence of mild solutions for quasilinear delay differential equations with nonlocalCauchy problem in Banach spaces. The results are established by using Hausdorff’s measure of noncompactness.Item Existence of Solutions to Quasilinear Delay Differential Equations with Nonlocal Conditions(International Journal of Mathematics Trends and Technology, 2014) Francis Paul Samuel; Tumaini Lisso; Kayiita ZacharyWe prove the existence and uniqueness of mild and classical solution to a quasilinear delay differential equation with nonlocal condition. The results are obtained by using C0-semigroup and the Banach fixed point theorem. AMS Subject Classification: 34G20, 47D03, 47H10, 47H20Item EXISTENCE OF SOLUTIONS FOR IMPULSIVE PARTIAL NEUTRAL FUNCTIONAL EVOLUTION INTEGRODIFFERENTIAL INCLUSIONS WITH INFINITE DELAY(International Journal of Pure and Applied Mathematics, 2013) T. Gunasekar; F. Paul Samuel; M. Mallika ArjunanThis paper investigates a class of impulsive partial neutral func- tional integrodifferential evolution inclusions with infinite delay in Banach spaces. The existence of mild solutions of these inclusions is determined under the mixed Lipschitz and Caratheodory conditions by using another nonlinear alternative of Leray-Schauder type for multivalued maps due to D. O’Regan. At the end, one example is presented. AMS Subject Classification: 34A60, 34A37, 34G25, 34B15Item EXISTENCE OF SOLUTIONS FOR IMPULSIVE QUASILINEAR MIXED VOLTERRA-FREDHOLM TYPE INTEGRODIFFERENTIAL EQUATIONS(International Journal of Pure and Applied Mathematics, 2014) F. Paul Samuel; K. Balachandran; T. GunasekarThe paper deals with the study of existence of solutions of quasilinear mixed volterra-Fredholm-type integrodifferential equations with nonlocal and impulsive conditions in Banach spaces. The results are obtained by using a fixed point technique and semigroup theory. AMS Subject Classification: 34A37, 34G60, 34G20Item Controllability Resultsfor Damped Second-OrderImpulsive Neutral Functional Integrodifferential SystemwithInfinite Delayin Banach Spaces(International Journal of Engineering Research and Development, 2013-05) F.Paul Samuel; T.Gunasekar; M.MallikaArjunanIn this paper, the controllability problem is discussed for the damped second-order impulsive neutral functional integro-differential systems with infinite delay in Banach spaces.Sufficient conditions for controllability results are derived by means of the Sadovskii’s fixed point theorem combined with an noncompact condition on the cosine family of operators. Anexample isprovidedtoillustratethetheory.Item Existence of Solutions for Neutral Functional Integrodifferential Evolution Equations with Non Local Conditions(Indian Journal of Science and Technology, 2015-02) S. Manimaran; T. Gunasekar; G. V. Subramaniyan; F. Paul SamuelWe study the existence of mild and strong solutions for nonlinear neutral functional integrodifferential evolution equations with nonlocal conditions in Banach spaces. The results are obtained by using the fractional powers of operators and Sadovskii’s fixed point theorem.Item Existence results for nonlocal impulsive neutral functional integro-differential equations(International Journal of Pure and Applied Mathematics, 2017) M.L. Suresh; T. Gunasekar; F. Paul SamuelIn this manuscript, we establish the existence of nonlocal impulsive neutral functional integro-differential equations with bounded delay in Banach spaces. Some existence results of mild solutions to such problems are obtained under the conditions in respect of the Hausdorff’s measures of noncompactness.Item CONTROLLABILITY RESULTS FOR SECOND ORDER IMPULSIVE NEUTRAL FUNCTIONAL INTEGRODIFFERENTIAL INCLUSIONS WITH INFINITE DELAY(Italian Journal of Pure and Applied Mathematics, 2013) F. Paul Samuel; T. Gunasekar; M. Mallika ArjunanThis paper is concerned with the controllability of a partial neutral func- tional integrodi®erential inclusion of second order with impulse e®ect and in¯nite delay in Banach spaces. The controllability of mild solutions using a ¯xed point theorem for contraction multi-valued maps and without assuming compactness of the family of cosine operators.Item Determination of Caffeine and pH Levels of Selected Carbonated Soft Drinks and Ready to Drink Juices in Eldoret, Kenya.(International Journal of Innovative Research in Engineering & Science, 2013-05) Magut Hillary; T. Anthoney Swamy; Terer Erick KipngetichDifferent brands of soft drinks and selected ready to drink juices were randomly sampled from different stores in Eldoret town. Two methods of extraction were employed; hydrochloric acid acidified water and distilled water. UV analysis results of acidified water samples, the caffeine levels were found to be in the range of 1.43 mg/L and 40.51 mg/L, the lowest being Stoney and the highest being Coca-Cola respectively. With distilled water alone, the concentration ranged from 1.51 to 39.65 mg/L, these being Stoney and Coca-Cola respectively. Ready to drink juices showed the highest levels of caffeine content in both distilled and acidified water extraction with the lowest reading of 59.43 mg/L obtained from Pineapple Marche brand while the highest concentration was from orange Marche brand with 75.71 mg/L caffeine in acidified water extraction.Item Physico-Chemical Study of Soil from Selected Maize Farms in Kamelilo, Kericho County(Int.J.Curr.Microbiol.App.Sci (2015) 4(10): 438-447, 2015) T. Anthoney Swamy; Terer Erick Kipngetich; Barasa Exevier; Magut HillaryPhysico-chemical study of soil was performed in this study to determine the levels of different physical and chemical parameters in seven selected maize farms. A total of 21 samples were collected in ploughed maize farms in Kamelilo Village in Kericho County for physico-chemical study. Samples were obtained from seven selected maize farms in triplicates. The physical parameters that were studied are pH and organic carbon while the chemical parameters like phosphorus, Sulphur and Nitrogen were determined. From the study, 71% of the soil samples had a low pH which makes the soil unsuitable for maize farming. The recommended pH for maize growing is 5 7 which has a positive effect on the availabilty of nitrogen and other plant nutrients. The percentage of organic carbon was rated as high in 90% of the soil samples with a minimum value of 1.03% organic carbon to a maximum value of 2.85% except in two sampling sites, sample 3a with 0.45% and sample 5a with 0.49% respectively exhibiting a low organic carbon value. It is the recommendation of the researchers that regular soil testing should be done to determine if the soil is in the ideal condition for a specific crop.