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Ultrasonic Sensor-Based Embedded System for Vehicular Collusion Detection and Alert

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Journal of Computer and Communications 2023年第8期11卷 44-57页

作者： Joe Essien calistus chimezie Department of Computer and Information Technology Veritas University Abuja Nigeria

The efficacy of an automated collision detection system is contingent upon the caliber and volume of data at its disposal. In the event that the data is deficient, incongruous, or erroneous, it has the potential to generate erroneous positive or negative outcomes, thereby compromising the system’s credibility. The occurrence of false positives is observed when the system erroneously identifies genuine activity as collusion. The phenomenon of false negatives arises when the system is unable to identify instances of genuine collusion. Collusion detection systems are required to handle substantial volumes of data in real time, capable of analyzing relationships between different objects. The intricate nature of collusion can pose difficulties in devising and executing efficient systems for its detection. The present study proposes an automated anti-collision system that utilizes sensor devices to detect objects and activate an alert mechanism in the event that the vehicle approaches the object in close proximity. The study introduces a novel methodology for mitigating vehicular accidents by implementing a combined system that integrates collision detection and alert mechanisms. The proposed system comprises an ultrasonic sensor, a microprocessor, and an alarm system. The sensor transmits a signal to the microcontroller, which in turn sends a signal to the warning unit. The warning unit is designed to prevent potential accidents by emitting an audible warning signal through a buzzer. Additionally, the distance information is displayed on an LCD screen. The Proteus Design Suite is utilized for simulation purposes, while *** is employed for implementation.

关键词： Ultrasonic Sensor Microcontroller Collision Detection Machine Learning Algorithms

Discrete Event Simulation-Based Evaluation of a Single-Lane Synchronized Dual-Traffic Light Intersections

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Journal of Computer and Communications 2023年第10期11卷 82-100页

作者： chimezie calistus Ogharandukun Martin Abdullahi Monday Essien Joe Department of Electrical/Electronic and Computer Engineering Veritas University Abuja Nigeria Department of Pure and Applied Physics Veritas University Abuja Nigeria Department of Computer Science Air Force Institute of Technology Kaduna Nigeria Department of Computer and Information Technology Veritas University Abuja Nigeria

This research involved an exploratory evaluation of the dynamics of vehicular traffic on a road network across two traffic light-controlled junctions. The study uses the case study of a one-kilometer road system modelled on Anylogic version 8.8.4. Anylogic is a multi-paradigm simulation tool that supports three main simulation methodologies: discrete event simulation, agent-based modeling, and system dynamics modeling. The system is used to evaluate the implication of stochastic time-based vehicle variables on the general efficiency of road use. Road use efficiency as reflected in this model is based on the percentage of entry vehicles to exit the model within a one-hour simulation period. The study deduced that for the model under review, an increase in entry point time delay has a domineering influence on the efficiency of road use far beyond any other consideration. This study therefore presents a novel approach that leverages Discrete Events Simulation to facilitate efficient road management with a focus on optimum road use efficiency. The study also determined that the inclusion of appropriate random parameters to reflect road use activities at critical event points in a simulation can help in the effective representation of authentic traffic models. The Anylogic simulation software leverages the Classic DEVS and Parallel DEVS formalisms to achieve these objectives.

关键词： Multi-Core Processing Distributed Computing Event-Driven Modelling Discrete Event Simulation Data Analysis and Visualization

Will an imperfect vaccine curtail the COVID-19 pandemic in the U.S.?

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Infectious Disease Modelling 2020年第1期5卷 510-524页

作者： Enahoro A.Iboi calistus N.Ngonghala Abba B.Gumel School of Mathematical and Statistical Sciences Arizona State UniversityTempeAZ85287USA Department of Mathematics University of FloridaGainesvilleFL32611USA Department of Mathematics and Applied Mathematics University of PretoriaPretoria0002South Africa Department of Mathematics Spelman CollegeAtlantaGeorgia30314USA

The novel coronavirus(COVID-19)that emerged from Wuhan city of China in late December 2019 continue to pose devastating public health and economic challenges across the *** the community-wide implementation of basic non-pharmaceutical intervention measures,such as social distancing,quarantine of suspected COVID-19 cases,isolation of confirmed cases,use of face masks in public,contact tracing and testing,have been quite effective in curtailing and mitigating the burden of the pandemic,it is universally believed that the use of a vaccine may be necessary to effectively curtail and eliminating COVID-19 in human *** study is based on the use of a mathematical model for assessing the impact of a hypothetical imperfect anti-COVID-19 vaccine on the control of COVID-19 in the United *** analytical expression for the minimum percentage of unvaccinated susceptible individuals needed to be vaccinated in order to achieve vaccine-induced community herd immunity is *** epidemiological consequence of the herd immunity threshold is that the disease can be effectively controlled or eliminated if the minimum herd immunity threshold is achieved in the *** of the model,using baseline parameter values obtained from fitting the model with COVID-19 mortality data for the U.S.,show that,for an anti-COVID-19 vaccine with an assumed protective efficacy of 80%,at least 82%of the susceptible US population need to be vaccinated to achieve the herd immunity *** prospect of COVID-19 elimination in the US,using the hypothetical vaccine,is greatly enhanced if the vaccination program is combined with other interventions,such as face mask usage and/or social *** combination of strategies significantly reduces the level of the vaccine-induced herd immunity threshold needed to eliminate the pandemic in the *** instance,the herd immunity threshold decreases to 72%if half of the US population regularly wears face masks in pu

关键词： COVID-19 SARS-CoV-2 Vaccination Social distancing Non-pharmaceutical intervention

Mineralogy and geochemistry of the Ngaoundaba Crater Lake sediments,northern Cameroon:implications for provenance and trace metals status

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Acta Geochimica 2021年第5期40卷 718-738页

作者： Armel Zacharie Ekoa Bessa John SArmstrong-Altrin Gentry calistus Fuh Thierry Bineli Betsi Tebogo Kelepile Paul-DesireNdjigui Department of Earth Sciences University of Yaounde IP.O.Box 812YaoundeCameroon Universidad Nacional Autonoma de Mexico Instituto de Ciencias del Mar Y LimnologıaUnidad de Procesos Oceanicos y CosterosCircuito exterior s/n04510 MexicoD.F.Mexico Department of Mining and Geological Engineering Botswana International University of Sciences and TechnologyPrivate Bag 16PalapyeBotswana

This study was conducted on the Ngaoundaba Crater Lake sediments to infer provenance,weathering conditions,organic matter accumulation,and trace metal *** Lake sediments were collected using a manual core sampler at 5 to 8 m water *** sediment cores from the littoral and center of the lake were analyzed for grain size distribution,water content(WC),organic matter content,mineralogy,and major and trace element *** Ngaoundaba sediments were classified as silt and sandy *** show high content in organic matter,which is more to the littoral than to the center of the lake,varying from 14.6%to 24%and21.2%to 40.8%,*** grain surface features identified by Scanning Electron Microscopy(SEM)show both chemical and mechanical microtextures with subrounded to angular shape suggesting both proximal and distal *** lake sediments are composed of quartz,kaolinite,and hematite,with low amounts of feldspars,rutile,calcite,illite,and *** indices such as the chemical index of alteration(CIA),chemical index of weathering(CIW),and index of compositional variability(ICV)indicate moderate to intense chemical weathering in the source area and immature to mature *** geochemical composition indicates that the sediments were derived from felsic to intermediate igneous rocks,such as granitoids,and mafic alkali lavas like *** environmental risk assessment of trace metals obtained by enrichment factor(EF)and geo-accumulation index(I-geo)shows low contamination of the lake sediments.

关键词： Ngaoundaba Crater Lake Mineralogy Geochemistry Provenance Metal traces status

The impact of age structure and vaccine prioritization on COVID-19 in West Africa

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Infectious Disease Modelling 2022年第4期7卷 709-727页

作者： Hemaho B.Taboe Michael Asare-Baah Afsana Yesmin calistus N.Ngonghala Department of Mathematics University of FloridaGainesvilleFL32611USA Laboratoire de Biomathematiques et d’Estimations Forestieres University of Abomey-CalaviCotonouBenin Department of Epidemiology University of Florida2004 Mowry RoadGainesvilleFL32610USA Emerging Pathogens Institute University of FloridaGainesvilleFL32610USA

The ongoing COVID-19 pandemic has been a major global health challenge since its emergence in *** to early predictions that sub-Saharan Africa(SSA)would bear a disproportionate share of the burden of COVID-19 due to the region's vulnerability to other infectious diseases,weak healthcare systems,and socioeconomic conditions,the pandemic's effects in SSA have been very mild in comparison to other ***,the number of cases,hospitalizations,and disease-induced deaths in SSA remain low,despite the loose implementation of non-pharmaceutical interventions(NPIs)and the low availability and administration of *** explanations for this low burden include epidemiological disparities,under-reporting(due to limited testing),climatic factors,population structure,and government policy *** this study,we formulate a model framework consisting of a basic model(in which only susceptible individuals are vaccinated),a vaccine-structured model,and a hybrid vaccine-age-structured model to assess the dynamics of COVID-19 in West Africa(WA).The framework is trained with a portion of the confirmed daily COVID-19 case data for 16 West African countries,validated with the remaining portion of the data,and used to(i)assess the effect of age structure on the incidence of COVID-19 in WA,(ii)evaluate the impact of vaccination and vaccine prioritization based on age brackets on the burden of COVID-19 in the sub-region,and(iii)explore plausible reasons for the low burden of COVID-19 in WA compared to other parts of the *** of the model parameters and global sensitivity analysis show that asymptomatic youths are the primary drivers of the pandemic in ***,the basic and control reproduction numbers of the hybrid vaccine-age-structured model are smaller than those of the other two models indicating that the disease burden is overestimated in the models which do not account for *** result is confirmed through the vaccine-d

关键词： Vaccine prioritization SARS-CoV-2 Omicron variant AVAT Reproduction number Herd immunity

A primer on using mathematics to understand COVID-19 dynamics: Modeling, analysis and simulations

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Infectious Disease Modelling 2021年第1期6卷 148-168页

作者： Abba B.Gumel Enahoro A.Iboi calistus N.Ngonghala Elamin H.Elbasha School of Mathematical and Statistical Sciences Arizona State UniversityTempeAZ85287USA Department of Mathematics Spelman CollegeAtlantaGA30314USA Department of Mathematics University of FloridaGainesvilleFL32611USA Emerging Pathogens Institute University of FloridaGainesvilleFL32610USA Department of Mathematics and Applied Mathematics University of PretoriaPretoria0002South Africa Merck&Co. Inc.2000 Galloping Hill RoadKenilworthNJ07033USA

The novel coronavirus(COVID-19)pandemic that emerged from Wuhan city in December 2019 overwhelmed health systems and paralyzed economies around the *** became the most important public health challenge facing mankind since the 1918 Spanish flu *** theoretical and empirical approaches have been designed and used to gain insight into the transmission dynamics and control of the *** study presents a primer for formulating,analysing and simulating mathematical models for understanding the dynamics of ***,we introduce simple compartmental,Kermack-McKendrick-type epidemic models with homogeneously-and heterogeneously-mixed populations,an endemic model for assessing the potential population-level impact of a hypothetical COVID-19 *** illustrate how some basic non-pharmaceutical interventions against COVID-19 can be incorporated into the epidemic model.A brief overview of other kinds of models that have been used to study the dynamics of COVID-19,such as agent-based,network and statistical models,is also *** extensions of the basic model,as well as open challenges associated with the formulation and theoretical analysis of models for COVID-19 dynamics,are suggested.

关键词： COVID-19 SARS-CoV-2 Non-pharmaceutical interventions Face mask Reproduction number

Stability Studies on the Aqueous Extract of the Fresh Leaves of Combretum Micranthum G. Don Used as Antibacterial Agent

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Journal of Chemistry and Chemical Engineering 2012年第5期6卷 417-424页

作者： Uduma Eke Osonwa Chukwuebuka Emmanuel Umeyor Uduak Victor Okon Emmanuel Maduabuchi Uronnachi calistus Dozie Nwakile Department of Pharmaceutics/Pharmaceutical Technology Faculty of Pharmaceutical Sciences Nnamdi Azikiwe University Agulu 422001 Anambra State Nigeria Department of Pharmaeeutics/Pharmaceutical Technology Faculty of Pharmacy University of Uyo Akwaibom State 520001 Nigeria

The fresh leaves of Combretum micranthum were harvested during the rainy season in Akwa Ibom State, washed and subjected to extraction by maceration in distilled water. Concentration was done with a rotary evaporator. The extracts were tested for content of the following phytochemicals using standard methods： alkaloids, saponins, tannins, anthraquinones, cardiac glycosides, flavonoids and steroids. Antibacterial sensitivity test of the extract was carried out on S. aureus, B. subtilis and E. coli using agar well diffusion method and Ampiclox as control. The effect of storage time of the extract on its antibacterial activity was determined after the extract was kept at room temperature for 1 h, 24 h, 48 h and 72 h, respectively. Preparations of 200 mg/mL of the aqueous extract were made with additives as follows：（a） no additive; （b） methyl paraben （0.3%）; （c） propyl paraben （0.3%）; （d） sodium metabisulfite （0.01%）; （e） A combination of methyl paraben （0.3%） and propyl paraben （0.3%）; （f） A combination of methyl paraben （0.3%）, propyl paraben （0.3%） and sodium metabisulfite （0.01%）. A visual observation of the stabilized preparations was employed on daily basis for 30 days. Phytochemical analyses on the aqueous extract of the fresh leaves showed the absence of alkaloids, anthraquinones and flavonoids. Saponins, cardiac glycosides and steroids were present in moderate amounts and there was abundance of tannins. The extract had similar effect on both S. aureus and E. coli cultures but activity was very low with B. subtilis. When S. aureus activity increased with time of storage up to 48 hours, thereafter the activity started reducing. However, the activity of E. coli continued to increase with time （within the study period）. Thus, it appears reasonable to store the extract for at least 48 hours before the use for enhanced activity.

关键词： Combretum micranthum fresh leaves aqueous extract antibacterial stability.

Screening Outcomes of Hepatitis B and E among HIV Patients on HAART in Osogbo, South Western Nigeria

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World Journal of AIDS 2016年第4期6卷 205-217页

作者： Bolaji E. Egbewale Victor O. Mabayoje M. A. Muhibi A. F. Mustapha calistus A. Akinleye Department of Community Health College of Health Sciences Ladoke Akintola University of Technology Osogbo Nigeria Department of Haematology and Blood Transfusion College of Health Sciences Ladoke Akintola University of Technology Osogbo Nigeria Department of Haematology LAUTECH Teaching Hospital Osogbo Nigeria Department of Medicine LAUTECH Teaching Hospital Osogbo Nigeria

Background: The lives of patients living with HIV/AIDs have improved in terms of longer life expectancy and quality. This has seen the emergence of complications of the disease and the drugs such as metabolic syndrome and re-emergence of tuberculosis. Co-infection with other viruses especially the hepatic viruses has also become a major source of concern. The aim of this research is to determine the incidence of hepatitis B and E among this group of patients. Methods and Findings: Blood samples were collected from 156 consecutive HIV positive patients on HAART, informed consent having been obtained previously. The patients were screened both for hepatitis B and E using standard procedures. A questionnaire was administered to all participants. The results are illustrated with tables following analysis with SPSS version 10. It was found that 24.5% were positive for hepatitis E while 7.8% were positive for hepatitis B. It was also found that educational status was the only statistical significant variable for HEV co-infection. Taking the value of alanine transaminase to be 12 U/L as upper limit of normal, the mean value for HEV positive patients obtained was 13.8U/L while for those HBV positive was 10U/L. Conclusion: From the findings, more emphasis should be placed on improving education of the populace. More research should be carried out to determine what subtypes of the viruses are present and their effects on the hepatic system using preferably non-invasive techniques. Also the variability of hepatic enzymatic activity needs more analysis.

关键词： Aids Transmission Viral HAART Hepatic