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he stochastic frontier analysis (SFA) model, designed to assess technical efficiency in production models, operates under the assumption of homoscedasticity. However, in practical scenarios, either the random error or the technical efficiency error, or both, can exhibit non-homoscedasticity. This research proposes heteroscedasticity correction measures for the random error (HCRE), technical efficiency error (HCTE), and both (HCRTE) within the SFA model. The study aims to determine which correction measure yields the most efficient parameter estimates when heteroskedasticity is present. The comparison involves evaluating the mean squared error (MSE) across different forms of heteroscedasticity and sample sizes through Monte Carlo simulations comprising 5000 replications. The findings indicate that attempting to correct for heteroskedasticity in the absence of such issues can adversely affect the parameter estimates of the SFA Model. Conversely, the HCRTE measure consistently produces the most efficient estimates when dealing with heteroskedasticity in terms of both random error and technical efficiency. Moreover, in cases where heteroskedasticity exists, applying the HCRTE measure not only enhances parameter estimates but also improves the technical efficiency measure of the SFA model.

Efficiency estimation in production technology has been a concern in economics, with methodologies such as Stochastic Frontier Analysis (SFA) playing a key role in this area. SFA has been pivotal in evaluating the efficiency of entities by isolating technical inefficiency from random production errors. However, despite its significance, the application of SFA faces challenges when the multicollinearity assumption underlying the model is violated. Therefore, this study presents a novel estimator, termed “Principal Component Analysis Estimation for Stochastic Frontier Analysis” (PCA-SFA), to address the problem of multicollinearity in the classical SFA model. The PCA-SFA estimator integrates Principal Component Analysis (PCA) to correct assumption violation arising from multicollinearity. Monte Carlo simulation study was conducted to ascertain the PCA-SFA performance, involving no fewer than 2,000 replications based on the Cobb-Douglas production function with varying levels of multicollinearity, represented by correlation coefficients ranging from 0.8, 0.9, 0.95, 0.99, and 0.999, and sample sizes (n) of 20, 50, 100, 250, and 1,000. The proposed estimator’s performance was compared to the classical SFA model using the Mean Square Error (MSE), Akaike Information Criterion (AIC), and Bayesian Information Criterion (BIC) as evaluation metrics. The results demonstrate that the PCA-SFA estimator consistently outperforms the classical SFA model. The PCA-SFA model showed significantly lower MSE, AIC, and BIC values, indicating improved precision and reliability in parameter estimation. The study, therefore, recommends that researchers and practitioners in econometrics and related fields consider integrating PCA-SFA into their production efficiency analytical frameworks, particularly when dealing with datasets prone to multicollinearity issues.

LogMAR charts are particularly useful for visual acuity (VA) measurement for low vision patients as they simplify conversion of non-standard viewing distance visual acuities to standard values. Also, the process of predicting various quantities involved in the prescrip-tion of optical devices for patients are greatly facilitated. However, the processes involved in the use of this logMAR principle require series of multiplication and division by the logMAR ratio of 1.2589. A table computed and pre-sented in this article provides easy reference for the conversions and predictions needed for the various quantities at near. The table (Table 1) is computed using the logMAR scale of 1.2589 in logMAR, M and N notations. The table con-tains VA values between logMAR 1.4 (10M or 80 point) and logMAR 0.18 (1.3M or10 point) in steps of 1.2589 for reduced (non-standard) viewing distances ranging from 31.8 cm (0.32 m) to 3.2 cm (0.03M). The table contains values which can be used to convert visual acuity values measured at reduced near view-ing distances to standard visual acuity values. The values also can be used to represent any of the quantities involved in the prescription of optical devices for low vision patients. The use of the table for converting reduced distance VA values to standard values and for predict-ing optical powers and visual performance of low vision patients are discussed with relevant examples. Like all principles based on the log-MAR principles, the table is quite versatile in VA conversion and prediction of the various quantities such as print size that can be read by the low vision patient when factors such as viewing distance or power are varied.

Background: The influence of inorganic fertilizer has posed considerable challenges on increasing food production worldwide. A careful plan is required to increase the yield and quality of crops. A profound knowledge on the use of organic manure involvement in plant growth and development could be beneficial for food production. The use of acceptable inorganic and different concentrations of vermicompost has been used in an attempt to enhance crop growth and development with the aim of increasing food production. The aim of the study was to investigate the impact of vermicompost tea concentrate extracted from cow manure and grass cutting on physiological responses of tomato (Solanum lycopersicum). Vegetative growth and yield of tomato was stimulated by mineralization of organic waste coupled with the mesophilic action of earthworm. Vermicompost is a by-product of earthworm tissues. It is a nutrient source rich in essential components for plant growth and development. Methods: An investigation was conducted in pot media under exposed natural conditions from August 2020 to November 2020 at Mangosuthu University of Technology. In this experiment, the growth of tomato plants were subjected to different vermicompost concentrations and amended with NPK fertilizer were studied. Sandy loam soil of about 5 kg were weighted into pot media (2.0mheight, 2.3m diameter). The experiment was set up in a completely randomized block design consisting of five treatments with five replicates per treatment. Treatments included: Positive control (PC), 5%VCL+NPK, 10% VCL+NPK, 20%VCL+NPK and the inorganic (NPK). Result: Results revealed that there were significant differences at (P<0.01) among the treatments with respect to plant height and number of leaves from week three to week eight. Similar trends were found with 5% VCL+NPK, 10% VCL+NPK, 20% VCL+NPK and the NPK treatments. This may be due to phytohormone release from earthworm tissue. Tomato flower inflorescence was significant at (P<0.01). Tomato fruit, different components at harvest which were, weight wet and dry weight were higher with NPK treated at (P<0.01) than the 5% VCL+NPK, 10% VCL+NPK. Root length in 20% concentration was considerably higher than the other treatments. The results showed that minimum supplementation with inorganic fertiliser may be necessary with vermicompost leachate in order to successfully grow crops in nutrient deficient soil. [ABSTRACT FROM AUTHOR]

Duplication or imitation of individual keystroke rhymes is very difficult which can make it very efficient to be used for identity authentication. Over time, it is possible that the keystroke style of an individual to be learned by following keystroke information obtained when the person types text. The user's identity can always be verified by studying the user's keyboard input styles anytime the user uses the keyboard. The technique suggested in this study uses the keystrokes that users make while typing to verify their identities. To provide an accurate verification of whether a user is authentic or fraudulent, a model that integrates machine learning and dynamic keystroke models--Decision Tree, Random Forest, Support Vector Machine, and K-nearest Neighbors--is compared and utilized. The keystroke dynamics dataset was gathered from Kaggle and consists of 51 subjects' keyboard dynamics data, which was collected over the course of eight sessions and six months. There are 20400 samples in all in the data. This study assessed the effectiveness of machine learning algorithms with a focus on the keystroke dynamic authentication system. Python is used for the development work, while Jupyter notebook is used as the IDE. The performance of the models for different variables is assessed using the following metrics: accuracy, error equal rate, parameter performance, threshold, training time, and testing time. According to the results, the accuracy of the Random Forest, Support Vector Machine, KNN, and Decision Tree algorithms are, respectively, 98, 97.55, 97.28, and 94.26%. Based on the comparing results, Random Forest outperforms the other models, suggesting that Random Forest can be used as the system model for Keystroke Dynamic authentication. [ABSTRACT FROM AUTHOR]

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Many businesses have been positively impacted by electronic commerce (ecommerce). It has enabled enterprises and consumers transact business digitally and experience diversity as long as the internet is accessible and there is a gadget to surf the internet. Several governments have gradually adopted electronic payment throughout the country. The Nigerian government has also done a lot of prodding toward the adoption of a cashless economy, which includes embracing ecommerce. As ecommerce expands, so does actual and attempted fraud through this channel. According to the Nigerian Central Bank, electronic fraud reached trillions of Naira by 2021. The purpose of this work was to employ logistic regression as a decision-making tool for detecting fraud in e-commerce platforms at either the virtual or physical point of sale. The main contribution of this research is a model developed using logistic regression for detecting fraud at the point of sale on electronic commerce platforms. The accuracy of the result is 97.8 percent. The result of this study will provide key decision makers in ecommerce firms with information on fraud patterns on their ecommerce platforms, this will enable them take quick actions to forestall these fraudulent attempts. Further research should be carried out using data from other developing countries. [ABSTRACT FROM AUTHOR]

The emerging scenario of robust Agricultural Extension and Advisory Services (AEAS) in Africa presupposes the need for Reality Television Shows (RTS) to support AEAS demand and delivery Systems. A variant of the entertainment-education (EE) genre, RTS provides an ample platform for effective AEAS. Given this, this study investigated crop farmers’ information needs in RTS utilization in Oyo State, Nigeria. A four-stage sampling procedure was used to select 140 crop farmers who own a television set randomly, while data was collected with the use of a structured questionnaire on respondents’ characteristics, perceived benefits and constraints to utilization of RTS and information needs on farmers’ crop enterprises from RTS. Data were analyzed using frequencies, percentages, means and PPMC at P= 0.05. Findings show that respondents were predominantly male (68.6%), married (65.7%) with tertiary education (40.0%), while mean age, farming experience and annual income were 46.10±13.395years 11.36±8.83years and N464464.29±95,805.94, respectively. The likelihood of RTS to facilitate the adoption of improved technologies (4.41±3.11) and the provision of information on key factors like marketing channels and production cost (2.73±3.11) were some of the perceived benefits by respondents. However, they had reservations about the language barrier (2.3643±4.9081) as a constraint to the maximal exploitation of the potentials of RTS. Respondents’ information need was high for irrigation system (2.61±2.54), harvesting activities (1.96±0.81), and marketing outlets (3.00±2.05), across production, harvesting and marketing information needs. It is recommended that proposed RTS should use local language for RTS dissemination, while addressing the most pressing information needs of the crop farmers.

From works in in-situ seepage through dams and laboratory experiments using Layered Heterogeneous Porous Media (LHPM), it has been noted that a refraction-like phenomenon, such as that experienced in light, affects fluids' flowlines when crossing the contact interface of layers characterised by different porosity viz-a-viz permeability. This concept has many applications in fluid dynamics, such as the dispersion process in stratified media. Currently, no study exists that models and analyses the relationship between the porosities of two layers in contact and the resulting flowline refraction using validated LHPM data. Hence, this work aims to establish a relationship between the porosity ratio (Φr) of stratified media made up of two layers and the refraction angle (θmax) of the maximum volume flux (qmax). Volume flux data from the flow of a single-phase fluid through five LHPMs with Φr ranging from 0.8325 to 0.9524 were used in the modelling. The flow was oriented from the lower to the higher porosity vis-à-vis permeability layer. It was found that θmax which is also the refraction angle of the peak solute plume flux, refracts away from the normal as Φr reduces. This indicates an increase in the dilution rate vis-à-vis spread of plumes with the reduction in homogeneity between the two layers. Also, θmax does not correlate with the stratification inclination (α), but the qmax which is also the peak solute plume flux correlates with α. Furthermore, an efficient model, which is the best-unbiased estimator, with R² = 0.99 was derived. Findings from this work can help better understand solute plume dispersion and the general fluid flow dynamics in stratified media such as capillary barrier effect covers for pollution control and hydrocarbon reservoirs. [ABSTRACT FROM AUTHOR]

Nigeria has recorded great losses since the outbreak of the COVID-19 pandemic in December 2019. Over-reliance on oil as source of national revenue and inadequate human capital development have impeded the country’s response to the global emergency. This study examines how technology education can stimulate a diversified economy to boost Nigeria’s capacity to withstand future crises. It employed a historical research method, comprising mainly secondary sources. The pandemic exposed the morbidity and inadequacy of Nigeria’s health facilities. In addition, a sharp drop in the global price of crude oil worsened the country’s wobbling economy during the pandemic. At the micro level, the lockdown imposed by government turned many self-employed Nigerians to idlers. The COVID-19 pandemic could have been a platform to enhance researches in medical sciences and health technology but the extant problems in the country’s higher education sector such as poor funding, lack of motivation for teaching and research, brain drain, and poor curriculum prevented meaningful innovation in that regard. The study recommends reforms in technology education to create a work force for non-oil sectors like agriculture, solid minerals, small and medium enterprises, and indigenous industries. This would stimulate self-reliance and a diversified economy to keep Nigeria unperturbed during future emergencies.

Climate change has resulted in challenging environmental issues, which have become a major global concern. Farmers therefore employ several methods which are adaptable to environmental hazards. The study assessed preferences of rice farmers' coping strategies to environmental hazards in Kwara state, Nigeria. Specifically, the study, assessed frequency of occurrence of the environmental hazards faced by the rice farmers, identified the preferred coping strategies used by rice farmers and determined the effects of environmental hazards on rice production. A two-stage random sampling technique was used to select 151 rice farmers on whom an interview schedule was administered. Descriptive statistics and Pearson Product Moment Correlation were used to analyzed the data. Results showed that 94.0% of the respondents were males 45.7 mean years old, 6.6 hectares of farm size and an average of 18.7 years of farming experience, flooding, erosion and wind storm having the highest occurrence frequency in rice production. Planting of improved varieties, early planting, avoiding to plant along river borders were the most preferred coping strategies used by rice farmers. Reduction in farm output, reduction in values of farm produce, decrease of farmers' income was identified as major effects of environmental hazards on rice production. There was also a significant relationship between age (r=0.3551), household size (r=0.215), farming experience (r=0.262) and the use of preferred coping strategies. The study concluded by identifying preferred coping strategies to environmental hazard in the study area and recommends that to reduce its effect on rice production, improved rice varieties should be made available at affordable and subsidized rate by the government and relevant bodies, timely and appropriate information on weather monitoring should be available to the rice farmers through reliable and appropriate channels. [ABSTRACT FROM AUTHOR]

This report shows the work index of Filin Kokuwa Gold ore sample in Bauchi State, Nigeria. The "reference sample (granites)" were sourced from outcrops of granites around Toro town. The samples were crushed, ground, and pulverized using appropriate laboratory milling machine. 80% passing size for the gold ore and granites samples were obtained at 100¹m sieve size for the ball mill feeds and products respectively. The work indexes of reference samples i.e. granites were used to calculate the work index of the Filin Kokuwa gold ore sample. The values of 13.277kWh/ton and 15.192kWh/ton were obtained respectively for the two different reference granites samples used and 14.21kWh/ton as their average which is the value of the work index of the Filin Kokuwa gold ore deposit. The energy required for grinding the ore was found to be 3.581kW. [ABSTRACT FROM AUTHOR]

Bushmint (Hyptis suaveolens Poit) is a weed with pesticidal properties that have been explored in managing pests of agricultural and medicinal importance. The objective of this study was to evaluate the repellence ability of Hyptis suaveolens to prevent infestation of stored maize grain seed. The study involved evaluation of the olfactory responses of adult weevil to maize (Zea mays L.) grains treated with 5, 10, 15 and 20% concentrations of leaf powder (LP) and methanol extract (ME) of Hyptis suaveolens in the laboratory, with a static air four-chamber olfactometer. Also, the insecticidal effects of the substances on adult mortality and oviposition on maize grains treated with LP and ME were determined in a completely randomised design, with four replicates. The number of weevils in ME chambers decreased with increase in concentration of extracts; while the LP chambers had consistently fewer weevils with numbers, ranging from 2.5 to 3.75. Adult mortality in maize treated with LP was the least and varied between 0.00 (15% concentration) and 2.54% (20% concentration). Maize grains with ME caused significant mortalities that ranged from 65.50% at 15% concentration to 94.92% at 10% concentration. More eggs (3.5 to 5.75) were laid on maize with LP compared with ME treated maize. Generally, ME was richer in phytochemicals than LP. Hyptis suaveolens repellence manifested more in the form of LP than as ME; though ME caused more adult mortality and reduced oviposition than LP. [ABSTRACT FROM AUTHOR]

This study analysed gender differences and profitability of pepper (Capsicum species) production in Kaduna State, Nigeria. A multi-stage sampling technique was adopted. One hundred pepper farmers were selected. Primary data sources were employed with the help of a well-designed and well-structured questionnaire. The results show that 66% of pepper farmers were between 21 and 50 years old. Pepper production was profitable in the study area. Gender differences in average costs and returns in pepper production revealed that the gross margin was higher for male farmers at 137,556.51 Naira than for female pepper farmers at 109, 711.77 Naira per hectare. The gender differences in factors influencing pepper production show that age (𝑋1), and fertiliser input (𝑋4), were significant factors influencing pepper production among male farmers at the 1% probability level, while age (𝑋1), labour input (𝑋3), and fertiliser input (𝑋4), were significant factors influencing pepper production among female farmers at the 1% probability level. The return to scale (𝑅𝑇𝑆) of pepper production was estimated at 2.798 for male farmers, which signifies an increase in the return to scale. The return to scale (𝑅𝑇𝑆) was calculated for female pepper farmers at 0.033, which implies a decrease in the return to scale. The major constraints faced by pepper farmers were: lack of fertilisers, pest and disease infestations, and inadequate capital. The study recommends that female pepper farmers should have more access to farm inputs and low interest loans to increase productivity.

The dire need for Itakpe iron ore concentrates of appreciable iron content meets for smelting operation necessitated this study. Core samples of the iron ore sourced from Itakpe, Kogi State, Nigeria were prepared for petrological analysis followed by chemical and particle size analyses. Froth flotation was done using different collectors at varying particle sizes and pH values. Characterization studies carried out revealed that Itakpe iron ore is a lean ore assaying 36.18% Fe2O3 and contains predominantly quartz, sillimanite, and haematite. Its liberation size lies favourably at 75 µm. Processing the ore by froth flotation yielded appreciable enrichment. Optimal recovery (~92%) was achieved using potassium amyl xanthate (PAX) at pH 11 for fine feed sizes (<125 µm) yielding iron concentrate assaying 67.66% Fe2O3. Thus, processing at this set-ofconditions is recommended for the industrial production of more enriched Itakpe iron ore concentrates. [ABSTRACT FROM AUTHOR]