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Accuracy Analysis on Solution of Initial Value Problems of Ordinary Differential Equations for Some Numerical Methods with Different Step Sizes
Get PDFIn this article, three numerical methods namely Euler’s, Modified Euler, and Runge-Kutta method have been discussed, to solve the initial value problem of ordinary differential equations. The main goal of this research paper is to find out the accurate results of the initial value problem (IVP) of ordinary differential equations (ODE) by applying the proposed methods. To achieve this goal, solutions of some IVPs of ODEs have been done with the different step sizes by using the proposed three methods, and solutions for each step size are analyzed very sharply. To ensure the accuracy of the proposed methods and to determine the accurate results, numerical solutions are compared with the exact solutions. It is observed that numerical solutions are best fitted with exact solutions when the taken step size is very much small. Consequently, all the proposed three methods are quite efficient and accurate for solving the IVPs of ODEs. Error estimation plays a significant role in the establishment of a comparison among the proposed three methods. On the subject of accuracy and efficiency, comparison is successfully implemented among the proposed three methods
Study on Properties of Concrete with Iron Ore Tailing and Glass Waste
Get PDFThe aim of this research is to test the characteristics of concrete by substitute fine aggregate with iron ore tailings and partial glass powder as in the place of cement. Concrete with waste products such as glass powder and iron ore tailings offer technical, economic and environmental advantages. In this experimental investigation, glass powder is replaced with cement by 10%, 20% and 30% and iron ore tailings with fine aggregates by 30% which is the optimum percentage. To study the role of glass powder and iron ore tailings combination in concrete. The properties such compressive strength, flexural strength, tensile strength and also durability parameters likely water absorption investigation for M40 concrete is carried out with different percentages of glass powder by keeping the iron ore tailings percentage constant. At 30% glass powder substitution as cement and sand with IOT increases concrete effectiveness. The concrete with 10% glass powder & 30% iron ore tailings showed a higher strength compared to the conventional mix for 28 days. Concrete mix containing 10% GP and 30% IOT showed higher flexural strength of 5.05 MPa for 28 days. Splitting tensile strength value is also increasing i.e., for 10% glass powder and 30% IOT, obtained splitting tensile strength was 4.48 MPa and modulus of elasticity value was has also increased. Water absorption experiment consequences results that water absorption decreases with an increase in GP percentage. The concrete workability tends to decrease when with glass powder content increase. Concrete containing 10% glass powder and 30% IOT showed maximum strength and it is considered as the optimum dosage
Classification of Disaster Risks in the Philippines using Adaptive Boosting Algorithm with Decision Trees and Support Vector Machine as Based Estimators
Get PDFThis paper employed the intelligent approach based on machine learning categorized as base and ensemble methods in classifying the disaster risk in the Philippines. It focused on the Decision Trees, Support Vector Machine, Adaptive Boosting Algorithm with Decision Trees, and Support Vector Machine as base estimators. The research used the Exponential Regression for missing value imputation and converted the number of casualties, damaged houses, and properties into five (5) risk levels using Quantile Method. The 10-fold cross-validation was used to validate the proposed algorithms. The experiment shows that Decision Trees and Adaptive Decision Trees are the most suitable models for the disaster data with the score of more than 90%, more than 75%, more than 75% in all the classification metrics (accuracy, precision, recall f1-score) when applied to classification risk levels of casualties, damaged houses and damaged properties respectively
Nanocomposite Obtained in the Plasma of a Pulsed High Voltage Discharge Using Nickel Electrodes and PTFE
Get PDFIn the plasma of pulsed high-voltage discharge, initiated between nickel electrodes in air, when the fluoroplastic is placed in the discharge gap, powder nanocomposite material has been synthesized. The nanocomposite contains NiF2 nanoparticles less than 5 nm in size, dispersed in a matrix consisting of carbon and fluorocarbon substances. The carbonaceous substance contains nanoscale disordered graphite-like regions. The fluorocarbon component of the composite contains fragments of PTFE molecules and fluorocarbon molecular fragments that differ in structure from PTFE molecule’s structure. After annealing the composite in air at 773 K, the initial nanocomposite is transformed into a nanocomposite containing nanosized PTFE and nanoparticles of NiF2 less than 5 nm in size, scattered in a matrix composed of nanographite and low-layer nanosized graphene, after aneling at 1173 K into a material containing NiO nanoparticles less than 10 nm in size. After annealing of the initial nanocomposite in argon atmosphere at 1073 K, the obtained nanocomposite contains Ni nanoparticles with sizes less than 5 nm and carbon and fluorocarbon components. The magnetic susceptibility of the unannealed nanocomposite is investigated. A transition to the antiferromagnetic phase at 73 K was detected. At T = 4K, exchange bias interaction of the AFM / FM type takes place in the composite. There is divergence of the FC and ZFC curves, which can be explained by the presence of a superparamagnetic phase or a spin glass phase in the sample. The field dependences of the magnetic susceptibility measured at T = 300 K show sharp changes that occur at certain values of the magnetic field. Elucidation of the nature of these changes requires additional research
Histopathological Effects of Seed Oil of Moringa oleifera Lam. on Albino Mice Infected with Plasmodium berghei (NK65)
Get PDFThe study assessed the histopathological effects of seed oil of Moringa oleifera on albino mice infected with Plasmodium berghei. This work included a good idea in the treatment of a causing agent of malaria with Moringa seed oil as bio-natural treatment. Thirty-five mice were divided equally and grouped into five. The mice were acclimatised for seven days and thereafter infected with 0.2 mL Plasmodium berghei (NK65) parasite. The parasites were allowed to establish in the mice for five days before commencement of treatment. Group A - negative control (untreated), group B - positive control (10mg/kg chloroquine treated), group C, D and E were respectively treated with 800, 400, 200 mg/kg seed oil of Moringa oleifera. By oral administration of 0.2 mL of treatment dose, treatment was carried out in four consecutive days and the mice were sacrificed five days thereafter. The liver and kidney extracted from the mice were processed for histological studies. Findings revealed group A had the least packed cell volume (PCV) of 22.23±1.98% and group B had the most PCV of 48.31±1.55% after treatment. The PCV in groups C, D and E were 45.34±1.11%, 41.40±1.00% and 39.19±1.82% respectively after treatment. Coagulative necrosis and inflammation characterised the liver and kidney of mice in groups C and D. Lesions were observed in all the liver of mice treated with the seed oil of M. oleifera and chloroquine. Overall, it can be inferred that the higher the PCV of mice after treatment, the higher the performance of chemotherapeutic agents against parasitaemia. Thus, at 800, 400 and 200 mg/kg dosage, the seed oil of Moringa oleifera could possibly treat malaria. However, administration of a higher dose of the oil and chloroquine should be with caution as both drugs may pose adverse effects on the kidney and liver
Excitonic States and Related Optical Susceptibility in InN/AlN Quantum Well Under the Effects of the Well Size and Impurity Position
Get PDFBased on the finite difference method, linear optical susceptibility, photoluminescence peak and binding energies of three first states of an exciton trapped by a positive charge donor-impurity (D+, X) confined in InN/AlN quantum well are investigated in terms of well size and impurity position. The electron, heavy hole free and bound excitons allowed eigen-values and corresponding eigen-functions are obtained numerically by solving one-dimensional time-independent Schrödinger equation. Within the parabolic band and effective mass approximations, the calculations are made considering the coupling of the electron in the n-th conduction subband and the heavy hole in the m-th valence subband under the impacts of the well size and impurity position. The obtained results show clearly that the energy, binding energy and photoluminescence peak energy show a decreasing behavior according to well size for both free and bound cases. Moreover, the optical susceptibility associated to exciton transition is strongly red-shift (blue-shifted) with enhancing the well size (impurity position)
Self-control and Mental Health? Exploring Perceptions of Control from the Experiences of Black and Minority Communities
Get PDFAlthough the disparities in mental health outcomes for ethnic minorities are well-documented, very little is known regarding service user perspectives and experiences from locus of control ambit. The aim of this qualitative study was to investigate the experiences of African and Caribbean service users, from the context of their Locus of Control (LOC). Informed by an Interpretivist approach, this study was conducted via in-depth interviews (N=10) and two focus groups (N=14). Purposive sampling methods were used to recruit mental health service users from a South London Borough to participate in the study. Data was collected through a semi-structured interview schedule and a focus group guide. Data analysis was informed by an Interpretive Phenomenology Analysis approach in the examination of the LOC profiles and service user perspectives. The study found that the drivers of LOC for the respondents were: perceived racism; perceived loss of control due to challenges pertaining to accessing employment, work stressors, lack of career advancement, socio-economic challenges; discrimination at work, identity challenges and entry to and exit pathways from mental health services, all of which promotes LOC externality. The findings suggest that mental health services need to take an active interest in factors that constitute externality in the LOC in assessment of the needs of A & C groups in clinical and community interventions. A holistic approach to psycho-social and socio-cultural issues are highly needed to improve the mental health outcomes for members of African and Caribbean communities with experience of mental health challenges
Sociodemographic Factors and Adoption of Social Media as a Management Tool by Managers and Administrators in Selected Non-Governmental Organizations in Kigali, Rwanda
Get PDFSocial media use has gained prominence in the public as well as in the work environment as a way of quickly and widely sharing information and its crucial role in management has been elevated even more by the covid-19 pandemic which has severely limited human physical interaction. This study was carried out to explore the sociodemographic factors and adoption of social media as a management tool among managers and administrators in selected Non-Governmental Organizations in Kigali Rwanda. The study focused on the popular social media applications that can be of use in management namely, Facebook, Twitter, WhatsApp, video-conferencing applications, and YouTube. The study employed a descriptive cross-sectional design with an online survey questionnaire administered to a sample size of 217 respondents purposively sampled from six selected NGOs in Kigali Rwanda. Findings indicated that the overall social media adoption was quite high with WhatsApp being the most popular app. Several respondents’ characteristics such as age, education and job level showed statistically significant association with adoption of particular social media applications. Findings, however, revealed no structured approach to social media use in most of the surveyed NGOs. The study concluded that the overall adoption rate of social media was quite high but with a huge disparity in usage rates of specific social media applications and that certain sociodemographic factors such as education level and training appeared as strong predictors of social media adoption. This study recommended therefore, that NGOs should determine the applications that support their business model and provide comprehensive policies and support to encourage the employees to adopt the chosen social media applications in their managerial functions. The policy makers should also promote the modifiable sociodemographic factors that influence social media adoption such as education level and training
A Value Centred Paradigm to Moderate the Digital Transformation of Manufacturing
Get PDFDigital transformation affects almost all areas of society and business and is of increasing interest to academics and industry practitioners. New digital technology is expected to enable manufacturing companies to capture competitive and productivity advantages compared to conventional methods. Aggregated information based on production process data represent a new production factor to generate innovative forms of digital value generation. Paradoxically, the implementation of digitalised production in manufacturing companies remains at unexpected low levels as companies’ investment decisions often vote against digitalisation due to uncertainty in judging novel forms of criteria related to digital value. Digital transformation constates a new set of latent structure and relationships to generate, capture and monetise value. A holistic view on heterogenous research disciplines related with digital transformation of production is proposed in this short communication. This research presents a new paradigm which takes the moderation function of value propositions, value architectures and value capture to evaluate projects relative to digitalised manufacturing
When Income Declines and Morbidity Rises: An Inquiry into Consumption Smoothing in the Transition to Retirement in China
Get PDFChina still relies on out-of-pocket (OOP) medical spending, having a high prevalence of catastrophic payments with large poverty impacts for individuals. Taking age-associated morbidity into account, people of an advanced age encounter health-related income shocks more often than younger cohorts. Exploiting the Harmonized China Health and Retirement Longitudinal Study (CHARLS), I use a fixed effects regression model to investigate whether pensions and health insurance allow for consumption smoothing in the presence of health shocks. I provide suggestive evidence that pensions slightly decrease non-food consumption when health shocks occur. Moreover, health insurance does not seem to completely substitute costly smoothing mechanisms. I record an ongoing trend of increasing OOP spending on hospitalization, with health insurance reducing these by 19 percent. Financial transfers from family members remain an important unofficial insurance channel for households to cope with health shocks