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2021

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Articles 31 - 60 of 27663

Full-Text Articles in Physical Sciences and Mathematics

Rural Electrification Using Iliceto Shield Wire Scheme In Developing Countries: Tanzania Case Study, Heavenlight M Munisi, Santos Kihwele Dec 2021

Rural Electrification Using Iliceto Shield Wire Scheme In Developing Countries: Tanzania Case Study, Heavenlight M Munisi, Santos Kihwele

Tanzania Journal of Science

Rural electrification rate in Tanzania is still very low despite the efforts made by the Rural Energy Agency (REA) in Tanzania. Rural electrification using medium voltage (MV) method has two major obstacles. First obstacle is high cost associated with the cost of extending the grid electricity to rural areas. Second obstacle is remoteness of the villages, which leads to high power loss during transmission. In lieu of economic extension of rural electrification areas, this paper proposes a low cost solution of Iliceto Shield Wire Scheme (ISWS). This technique involves insulating shield wires (SW) from high voltage (132-400 kV) transmission line …


Physico-Chemical Properties Of Mechanically Extracted Banana Juice At Different Ripening Stages, Mathayo G Mathias, Lilian D Kaale, Oscar Kibazohi Dec 2021

Physico-Chemical Properties Of Mechanically Extracted Banana Juice At Different Ripening Stages, Mathayo G Mathias, Lilian D Kaale, Oscar Kibazohi

Tanzania Journal of Science

This paper presents the findings of a study on physico-chemical properties of low viscosity banana juice from five banana cultivars: Pisang Awak (PSA) an ABB genome, Yangambi km5 (YKM5) an AAA genome and cultivars from AAA-EA genome, namely Mbilabile, Ndeshi and Mlonga. Low viscosity banana juice was extracted using improved mechanical method at five ripening stages. The physico-chemical properties significantly varied according to cultivars and ripening stages (p < 0.05). Yields, total soluble solids (TSS), titratable acidity (TA) and pH were in the range of 19.50–74.03%, 7.33–27.64 ºBrix, 0.37–0.76% malic acid equivalent and 4.09–4.70, respectively. Yields decreased in the order of Mbilabile > Ndeshi > Mlonga > YKM5 > PSA whereas the total soluble solids increased as follows Mlonga < Mbilabile < Ndeshi < YKM5 < PSA. Furthermore, ashes and mineral contents decreased with ripening stages whereas the low viscosity banana juice was rich in potassium and magnesium. Finally, the study recommends stage 5 of the ripeness as ideal for producing low viscosity banana juice. Keywords: Mechanical extraction, Banana cultivar, Ripening stage, Tannin, Banana juice.


Analysis Of The Current And Future Land Use/Land Cover Changes In Peri-Urban Areas Of Dar Es Salaam City, Tanzania Using Remote Sensing And Gis Techniques, Erick T Mnyali, Silvia F Materu Dec 2021

Analysis Of The Current And Future Land Use/Land Cover Changes In Peri-Urban Areas Of Dar Es Salaam City, Tanzania Using Remote Sensing And Gis Techniques, Erick T Mnyali, Silvia F Materu

Tanzania Journal of Science

A rapid increase in population and urban development has direct impacts on the natural environment of peri-urban areas of big cities, especially in the developing countries. This study examined land use and land cover changes (LULCC) of peri-urban areas of Kinondoni Municipality in Dar es Salaam city for the period between 1999 and 2019 and predicted future changes by 2039. The specific objectives were to; (i) map the spatial-temporal land use and cover changes (ii) analyze settlements (built-up areas) patterns and factors influencing their changes (iii) predict changes that might happen for the next two decades. LULCC for 1999 to …


Atmospheric Instability Conditions During Rainy Seasons Over Tanzania, Pasvolo J Mwinuka, Christian Bs Uiso, Ladslaus B Chang’A, Mwingereza J Kumwenda Dec 2021

Atmospheric Instability Conditions During Rainy Seasons Over Tanzania, Pasvolo J Mwinuka, Christian Bs Uiso, Ladslaus B Chang’A, Mwingereza J Kumwenda

Tanzania Journal of Science

The amount of rainfall and its distribution in time and space is dependent on the atmospheric instability conditions, and on its moisture content. The aim of this study was to determine the atmospheric instability conditions during January to March (JFM), February to April (FMA), March to May (MAM), and October to December (OND) rainy seasons over local climate zones in Tanzania. Zone area average seasonal Convective Available Potential Energy (CAPE), Convective Inhibition (CIN), Precipitable Water (PW) and Lifted index (Li) were calculated and analyzed. Results showed Li < 0 in JFM and FMA over whole Tanzania. During MAM and OND, Li < 0 over the Lake Zone, Western Highlands Zone and Central Zone only. CAPE ranged from 793 J/kg to 1183 J/kg during JFM, and 700 J/kg to 1080 J/kg during FMA. During MAM, CAPE ranged from 170 J/kg to 921 J/kg and from 173 J/kg to 833 J/kg during OND. Results also showed CAPE > 1000 J/kg over the Lake Zone, Western Highlands Zone, Island Zone, and Central …


Modelling The Impact Of Undetected Cases On The Transmission Dynamics Of Covid-19, Herieth Rwezaura Dec 2021

Modelling The Impact Of Undetected Cases On The Transmission Dynamics Of Covid-19, Herieth Rwezaura

Tanzania Journal of Science

The spread of COVID-19 globally has caused negative impacts to the public, making understanding the dynamics of transmission a necessity. Essential factors such as undetected cases, asymptomatic cases, and several non-pharmaceutical interventions have played significant roles in the spreading mechanism of COVID-19 in the human population. It is imperative to understand the significance of these factors in order to determine whether COVID-19 will be eradicated or will continue to persist in the population. A mathematical model is formulated to investigate the impacts of vaccination and several non-pharmaceutical interventions on the dynamics of a COVID-19 accounting for asymptomatic cases, detected (identified) …


Characterization Of The Ch Addition Product From Meta- And Ortho-Xylene + Ch Reaction And Direct Experimental Observation Of The Tetrabromine Cluster Br4 Using Synchrotron Photoionization Mass Spectrometry, Rory R. Mcclish Dec 2021

Characterization Of The Ch Addition Product From Meta- And Ortho-Xylene + Ch Reaction And Direct Experimental Observation Of The Tetrabromine Cluster Br4 Using Synchrotron Photoionization Mass Spectrometry, Rory R. Mcclish

Master's Theses

This thesis is centered on the use of a unique gas-phase spectroscopy technique to characterize products and elucidate reaction mechanisms. Experiments were carried out at the Chemical Dynamics Beamline 9.0.2 of the Advanced Light Source located at the Lawrence Berkeley National Laboratory in Berkeley, CA. Computational work was performed on the scientific supercomputer at USF to supplement experimental findings. Chapter 1 contextualizes the work spurred in response to the deleterious interactions of anthropogenic emissions on Earth’s climate. Chapter 2 describes the theoretical manipulations foundational to the experimental design and interpretation. Chapter 3 delves into the physical details of the experimental …


Optical And Chemical Properties Of Fragaria Ananassa And Galena: Potential Photosensitizers In A Natural Dye-Sensitized Solar Cell, Ibukun S Akinsola, Aderemi B Alabi, Coppede Nicola Dec 2021

Optical And Chemical Properties Of Fragaria Ananassa And Galena: Potential Photosensitizers In A Natural Dye-Sensitized Solar Cell, Ibukun S Akinsola, Aderemi B Alabi, Coppede Nicola

Tanzania Journal of Science

Dye is one of the major components for high power conversion efficiency in a dye-sensitized solar cell. There are challenges natural dyes encounter, especially with quick degradation of the dye molecules. This work considered mineral dye in comparison with plant dye to address the challenge of degradation of natural plant dyes. The optical properties and functional groups of the two natural dyes were studied in this work. The absorption spectra, the optical band gaps and the absorption coefficients of the dyes were reported and found to be suitable for use as photosensitizers in a dye-sensitized solar cell (DSSC), as they …


Environmental Noise Pollution And Its Impacts On The Hearing Ability Of Men And Women In Ilorin, Kwara State, Nigeria, Afolabi M. Tunde, Salamat Abdulquadri Dec 2021

Environmental Noise Pollution And Its Impacts On The Hearing Ability Of Men And Women In Ilorin, Kwara State, Nigeria, Afolabi M. Tunde, Salamat Abdulquadri

Tanzania Journal of Science

Noise is an environmental disturbance that has harmful effects on the physiological and psychological lives of human beings and animals. This work examined the perceived health implications associated with noise pollution on both genders in Ilorin, Nigeria. It specifically identified the major sources of noise pollution, assessed noise pollution levels in the selected areas and determined the differences in the impacts of noise pollution on the health of both genders in Ilorin. A total of 384 respondents were sampled. Sound Level Meter (SLM) was used to ascertain the levels of noise in the study areas. Descriptive statistics and ANOVA were …


Paleodepositional Environment And Sequence Stratigraphy Of Miocene Sediments In Well Tn-1, Coastal Swamp Depobelt, Niger Delta Basin, Nigeria, Jerry Osokpor, Efetobore G Maju-Oyovwikowhe Dec 2021

Paleodepositional Environment And Sequence Stratigraphy Of Miocene Sediments In Well Tn-1, Coastal Swamp Depobelt, Niger Delta Basin, Nigeria, Jerry Osokpor, Efetobore G Maju-Oyovwikowhe

Tanzania Journal of Science

This research focused on the interpretation of paleodepositional environment and development of a sequence stratigraphic framework for the well TN-1 section, located in the coastal swamp depositional belt of the Niger Delta Basin. Integration of interpreted litho- and biofacies data sets that facilitated the interpretation of the paleodepositional environment enabled the erection of a sequence-stratigraphic framework. Three lithotypes (sand, clay, and shale) distributed within fourteen facies variants were integrated with palynomorph components to delineate five paleodepositional cycles ranging from distal delta plain to bathyal. Eight systems tracts (closely related to depositional cycles, but transcended depositional boundaries in some intervals) that …


Determination Of Cramer-Rao Lower Bound (Crlb) And Minimum Variance Unbiased Estimator Of A Dc Signal In Awgn Using Laplace Transform, Abdi T. Abdalla Dec 2021

Determination Of Cramer-Rao Lower Bound (Crlb) And Minimum Variance Unbiased Estimator Of A Dc Signal In Awgn Using Laplace Transform, Abdi T. Abdalla

Tanzania Journal of Science

This paper presents an alternative approach for the determination of Cramer-Rao Lower Bound (CRLB) and Minimum Variance Unbiased Estimator (MVUE) using Laplace transformation. In this work, a DC signal in Additive White Gaussian Noise (AWGN) was considered. During the investigation, a number of experiments were conducted to analyze different possible outputs under different conditions, and then the patterns of the outcomes were studied. Finally closed-form expressions for the CRLB and MVUE were deduced employing the Laplace transformation. The resulting expressions showed that the proposed method has almost the same number of steps as the existing method. However, the latter requires …


Temperature Effects On The Corrosion Inhibition Of Mild Steel In Sulfuric Acid Solution By Acacia Senegal Gum With Halide Ions, Jovine Emmanuel, Joseph Buchweishaija Dec 2021

Temperature Effects On The Corrosion Inhibition Of Mild Steel In Sulfuric Acid Solution By Acacia Senegal Gum With Halide Ions, Jovine Emmanuel, Joseph Buchweishaija

Tanzania Journal of Science

The effects of temperature on the inhibitive effect of naturally occurring Acacia senegal gum exudate on the corrosion of mild steel in sulfuric acid was studied between 35 and 70 °C using electrochemical impedance spectroscopy and potentiodynamic polarization methods. Findings showed that Acacia senegal gum exudate decreases the corrosion rate of mild steel. The inhibition efficiency declined with raising temperature above 35 °C. The increase in the corrosion rate with increasing temperature was observed for both uninhibited and inhibited systems. Addition of halide ions to the Acacia senegal gum exudate solution enhanced the corrosion inhibition efficiency because of synergistic effects, …


Analogue Sandbox Scaled Modelling Of Oblique And Orthogonal Extension Rifting In Rukwa Rift Basin, Tanzania, Tonny Ojok, John Bk Duot, Majorine Namaganda, Nasra Sadiki, Michael Msabi Dec 2021

Analogue Sandbox Scaled Modelling Of Oblique And Orthogonal Extension Rifting In Rukwa Rift Basin, Tanzania, Tonny Ojok, John Bk Duot, Majorine Namaganda, Nasra Sadiki, Michael Msabi

Tanzania Journal of Science

Fault evolution in oblique and orthogonal rift systems in the brittle upper crust of the Rukwa rift basin was simulated using scaled sandbox modelling by varying the angle between the rift axis and the extension direction, α, through 45° and 90°, over a 10 cm displacement. The 45° oblique model exhibits a half-graben architecture bounded by a planar fault, intra-rift faults and a conjugate fault in some vertical sections. The map view of the model’s basin trends in the NW-SE direction, and is comparable with the Rukwa rift basin orientation. The 90° oblique model forms a basin structure which is …


Design And Performance Analysis Of Composite Airfoil Wind Turbine Blade, Hegespo H Mwanyika, Yusufu Ac Jande, Thomas Kivevele Dec 2021

Design And Performance Analysis Of Composite Airfoil Wind Turbine Blade, Hegespo H Mwanyika, Yusufu Ac Jande, Thomas Kivevele

Tanzania Journal of Science

Small horizontal axis wind turbine rotors with composite airfoil rotor blades were designed and investigated in the present study in order to improve its performance in low wind speed and low Reynolds number (Re) conditions for standalone system. The geometrical and aerodynamic nature of a single airfoil small horizontal axis wind turbine blade curtails efficient energy harnessing of the rotor blade. The use of composite airfoil rotor blade improves energy production but imposes uncertainty in determining an optimal design angle of attack and the off design aerodynamic behaviour of the rotor. This research investigated the effects of two airfoils used …


Optimal Design Of Hybrid Renewable Energy For Tanzania Rural Communities, Ester T Marcel, Joseph Mutale, Aviti T Mushi Dec 2021

Optimal Design Of Hybrid Renewable Energy For Tanzania Rural Communities, Ester T Marcel, Joseph Mutale, Aviti T Mushi

Tanzania Journal of Science

Rural communities in developing countries lack access to electricity due to high costs of grid extension. This paper proposes a hybrid system of renewable energy (HRES) as solution. The HRES consists of solar, wind, and battery energy storage (BES). The village called Ngw’amkanga in Shinyanga region of Tanzania, East Africa is selected as a case study. An iterative method to determine the size of wind and solar photovoltaic (PV) generation required assuming a project life of 25 years at minimum annualised cost of the system ( ) is proposed. The project life time is fixed on the life span of …


Application Of Faulkenberry (2018) Bayes Factor To A Balanced Two Way Analysis Of Variance With Random Effects, Onyeike D. Egburonu, Omotayo A. Abidoye Dec 2021

Application Of Faulkenberry (2018) Bayes Factor To A Balanced Two Way Analysis Of Variance With Random Effects, Onyeike D. Egburonu, Omotayo A. Abidoye

Tanzania Journal of Science

The Analysis of Variance technique estimates variance components by comparing their mean squares to their expected values. Nevertheless, this method could give variance component estimates that are found outside the parameter space, i.e. negative estimates. In a bid to overcome this deficiency, alternate approaches are essential, and likelihood-based approaches have become common over time. Bayesian techniques have also been proposed and Bayes factors developed for examining various models. We applied the Bayes factor proposed by Faulkenberry (2018) to a Balanced Two Way ANOVA under three (3) cases, namely Case 1: the levels of the two factors are fixed; Case 2: …


Smart Electric Meter Deployment In Tanzania: A Survey, Theresia B Maziku, Kwame S Ibwe, Abdi Abdalla, Ellen A Kalinga Dec 2021

Smart Electric Meter Deployment In Tanzania: A Survey, Theresia B Maziku, Kwame S Ibwe, Abdi Abdalla, Ellen A Kalinga

Tanzania Journal of Science

Using information and communication technologies (ICT) to make the electrical power network intelligent and smarter (smart grid) has been the focal point in transforming electrical power industry. The idea behind smart grid is to transform the Tanzanian power sector into a secure, adaptive, sustainable, and digitally enabled ecosystem that provides reliable and quality energy for all with active participation of stakeholders. Smart metering is a central segment in realizing smart grid. However, a big question is whether Tanzanian power stakeholders are ready for smart metering technology investments for household applications. Operation and maintenance of a smart metering solution is a …


Adaptive Sliding Mode Contouring Control Design Based On Reference Adjustment And Uncertainty Compensation For Feed Drive Systems, Mathew Renny Msukwa, Santos Kihwele Dec 2021

Adaptive Sliding Mode Contouring Control Design Based On Reference Adjustment And Uncertainty Compensation For Feed Drive Systems, Mathew Renny Msukwa, Santos Kihwele

Tanzania Journal of Science

Industrial feed drive systems, particularly, ball-screw and lead-screw feed drives are among the dominating motion components in production and manufacturing industries. They operate around the clock at high speeds for coping with the rising production demands. Adversely, high-speed motions cause mechanical vibrations, high-energy consumption, and insufficient accuracy. Although there are many control strategies in the literature, such as sliding mode and model predictive controls, further research is necessary for precision enhancement and energy saving. This study focused on design of an adaptive sliding mode contouring control based on reference adjustment and uncertainty compensation for feed drive systems. A combined reference …


Biodiesel Generation From Palm Kernel Biomass Via An In-Situ Transesterification Approach, Chikaodili D Ikechukwu, Ikhazuagbe H Ifijen, Nyaknno U. Udokpoh Dec 2021

Biodiesel Generation From Palm Kernel Biomass Via An In-Situ Transesterification Approach, Chikaodili D Ikechukwu, Ikhazuagbe H Ifijen, Nyaknno U. Udokpoh

Tanzania Journal of Science

This study investigated an in-situ transesterification of palm kernel biomass at variable reaction times (4 h, 5 h and 6 h) and catalyst loading (2 wt%, 3 wt.% and 5 wt.%). The biodiesel yields were observed to vary with these parameters. GC-MS analysis showed high fatty acid methyl esters (FAMEs) contents for all the prepared biodiesel samples (C-18:1, C-14:0, C-16:0, and C-18:0). 2 wt.% catalyst loading and 4 h reaction time were observed to be the best reaction conditions from the experimented parameters that gave the best biodiesel yield at 300 rpm mixing intensity. The in-situ method recorded a higher …


Mathematical Characterization Of Biological Control Of Cassava Pests Model, Yidiat O. Aderinto, Faith O. Ibiwoye, Michael O. Oke, Folashade M. Jimoh Dec 2021

Mathematical Characterization Of Biological Control Of Cassava Pests Model, Yidiat O. Aderinto, Faith O. Ibiwoye, Michael O. Oke, Folashade M. Jimoh

Tanzania Journal of Science

Pests are major constraints to the effective growth and development of every crop through their damage, and can be controlled effectively by the use of their natural enemies which is referred to as the biological pest control. In this study, the biological control model of cassava pests through optimal control theory was presented in order to minimize the population of the pests and stabilize the natural enemies population so as not to affect the crop negatively. A mathematical model was formulated via the Lotka-Volterra model, and the model was characterized. The optimality system was established, the equilibrium point with its …


Mitigating The Spread Of Measles Under Constrained Health Care Resources In Tanzania Using Social Contact Network Models, Herieth Rwezaura, Seán Mcgarraghy Dec 2021

Mitigating The Spread Of Measles Under Constrained Health Care Resources In Tanzania Using Social Contact Network Models, Herieth Rwezaura, Seán Mcgarraghy

Tanzania Journal of Science

Tanzania revaccinates individuals during measles outbreaks, despite having scant healthcare resources. We construct epidemiological models of measles spread by employing a hybrid of existing social contact networks models to develop SEIR simulation model. Using demographic and measles surveillance data from three rural villages in Tanzania, we simulate the spread of measles and examine which vaccination strategies can effectively control outbreaks. Results strongly indicate the spread of measles largely depends on contact rates among infected individuals within a population. Findings indicate a need for targeted vaccination for children of 6 months to 15 years of age, but equally for unvaccinated older …


2021 - Tennessee Annual Climate Summary, Tennessee Climate Office, East Tennessee State University Dec 2021

2021 - Tennessee Annual Climate Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.


Long Term Observation Of The Grassland Vegetation Used Intensively Or Extensively And Ecologically, H.-D. Matthes, J. Matthes, W. Jentsch, V. Pastushenko Dec 2021

Long Term Observation Of The Grassland Vegetation Used Intensively Or Extensively And Ecologically, H.-D. Matthes, J. Matthes, W. Jentsch, V. Pastushenko

IGC Proceedings (1977-2023)

The aim of the present paper was to study alterations of the grassland flora from 55 plots following a more extensive management under long term observation within 6 years. Extensification of grassland use leads to an increase of the numbers of plant species by 32%, “Red-list-species” included. The moisture number of the soils slightly increased and the reaction and nitrogen numbers decreased. Results are presented for different vegetation units.


Influence Of Extensive Management On Botanical Composition Of Permanent Meadow Sward, K. Mlynarczyk, E. Korona, E. Marks Dec 2021

Influence Of Extensive Management On Botanical Composition Of Permanent Meadow Sward, K. Mlynarczyk, E. Korona, E. Marks

IGC Proceedings (1977-2023)

The aim of undertaken investigations was to find the possibilities of grassland management with special respect to the biodiversity and the landscape conservation. Changes in botanical composition of the meadow sward against a background of different mowing utilization were examined on the semi-natural meadows situated on the peat-mursh soil in Masurian Landscape Park (north-east Poland). The areas mown with biennial pause and completely turned off from uses followed gradual simplifying of species composition and increasing of bog species participation. Results show on advisability of passing one harvest each year or with one-year pauses.


Vegetation Changes In Sown Grassland In The Uk After Nine Years Of Extensive Grazing Management, C. A. Marriott, G. T. Barthram Dec 2021

Vegetation Changes In Sown Grassland In The Uk After Nine Years Of Extensive Grazing Management, C. A. Marriott, G. T. Barthram

IGC Proceedings (1977-2023)

The effect of extensive grazing management with sheep on vegetation change in sown pastures (initially containing Lolium perenne and Trifolium repens) in the uplands of Scotland was investigated from 1990-1999. One treatment was representative of current more intensive management systems; it was fertilized, and maintained at a sward surface height of 4 cm. Two treatments were unfertilized and were maintained at sward surface heights of 4 cm or 8 cm; the ewe numbers carried on these treatments averaged 74% and 44%, respectively, of those on the fertilized treatment. In all treatments the sheep were Scottish Blackface ewes. Their single …


The Influence Of Rising Atmospheric Co2 On Grassland Ecosystems, J. A. Morgan, P. C. D. Newton, J. Nösberger, C. E. Owensby Dec 2021

The Influence Of Rising Atmospheric Co2 On Grassland Ecosystems, J. A. Morgan, P. C. D. Newton, J. Nösberger, C. E. Owensby

IGC Proceedings (1977-2023)

Increasing atmospheric CO2 concentrations and climatic change will have significant effects on the ecology of grasslands. This paper evaluates results from four CO2 enrichment studies in contrasting grasslands. A Swiss study investigates the effects of elevated CO2 (600 μL L-1 CO2) on perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L), a New Zealand study examines how elevated CO2 (475 μL L-1 CO2) affects a botanically diverse pasture, and studies in the Kansas tallgrass prairie and the Colorado shortgrass steppe investigate the effects of an approximate …


A Novel Arabic Corpus For Text Classification Using Deep Learning And Word Embedding, Roua A. Abou Khachfeh, Islam El Kabani, Ziad Osman Dec 2021

A Novel Arabic Corpus For Text Classification Using Deep Learning And Word Embedding, Roua A. Abou Khachfeh, Islam El Kabani, Ziad Osman

BAU Journal - Science and Technology

Over the last years, Natural Language Processing (NLP) for Arabic language has obtained increasing importance due to the massive textual information available online in an unstructured text format, and its capability in facilitating and making information retrieval easier. One of the widely used NLP task is “Text Classification”. Its goal is to employ machine learning technics to automatically classify the text documents into one or more predefined categories. An important step in machine learning is to find suitable and large data for training and testing an algorithm. Moreover, Deep Learning (DL), the trending machine learning research, requires a lot of …


A Poisson-Akash Inrar(1) Model For Over Dispersed Count Time Series, Emmanuel W. Okereke, Sunday N. Gideon Dec 2021

A Poisson-Akash Inrar(1) Model For Over Dispersed Count Time Series, Emmanuel W. Okereke, Sunday N. Gideon

BAU Journal - Science and Technology

In this paper, a Poisson-Akash INAR(1) model was proposed in order to improve on the modelling of overdispersed stationary count time series. The estimators of the parameters of the model were derived using the Yule-Walker (YW) method and the conditional least squares (CLS) method. An expression for the conditional log-likelihood and the r-step ahead forecast were obtained for the model. Three overdispersed nonseasonal stationary count time series were modelled to illustrate the applicability of the proposed model as well as its capacity to outperform the competing INAR (1) models in modelling overdispersed stationary count time series and the result showed …


Walking Diagonally: A Simple Proof Of Countability Of The Set Of All Finite Subsets Of Naturals, Miroslav Kures Dec 2021

Walking Diagonally: A Simple Proof Of Countability Of The Set Of All Finite Subsets Of Naturals, Miroslav Kures

BAU Journal - Science and Technology

The countability of the set of finite subsets of natural numbers is derived. In addition to the derivation itself, the use of diagonal method is illustratively presented; thinking about infinite sets relate to the name of Georg Ferdinand Ludwig Philipp Cantor, the creator of set theory, which has become a fundamental theory in mathematics. The proof of the claim is original, although the theorem is an analogy with the famous theorem about the countability of rational numbers. A certain insight into the subsets of natural numbers is given. Anyway, the technique could be considered already at high school level as …


Role Of Technological Revolution In Transport And Communications Development, Mohamad B. Chami Dec 2021

Role Of Technological Revolution In Transport And Communications Development, Mohamad B. Chami

BAU Journal - Science and Technology

The arousal of technology has changed a lot of aspects in human life and has drastically changed its path through a revolution that changed the whole world. This revolution took place in various aspects while affecting significantly the global economy and from those fields that considerably affect the life of human beings in the previous and current centuries are Information and Communication Technology (ICT) and transportation. It is these two factors that play a major role in the economy of countries and dominate the lives of societies in the world. Thus, this paper studies the impact of the technology revolution …


The Inhibition Activity Of Tert-Butylhydroquinone Towards Corrosion Of Aluminum, Copper And Stainless Steel In Biodiesel Blend B20 Alternative Fuel, Chaza Joumaa, Ibtissam Saad, Ghassan Younes Dec 2021

The Inhibition Activity Of Tert-Butylhydroquinone Towards Corrosion Of Aluminum, Copper And Stainless Steel In Biodiesel Blend B20 Alternative Fuel, Chaza Joumaa, Ibtissam Saad, Ghassan Younes

BAU Journal - Science and Technology

Tert-butylhydroquinone (TBHQ) has been investigated as corrosion inhibitor for aluminum; copper and stainless steel in biodiesel blend B20 by using electrochemical impedance spectroscopy (EIS) method. The results showed that the inhibition efficiency increases with an increase in the concentration of TBHQ but decreases with increasing temperature from 30℃ to 60℃. A maximum inhibition efficiency of about 61.52% for aluminum was recorded for THBQ in biodiesel blend B20 at temperature 30℃ and at a concentration of 4x10-6 M which is the lowest concentration used compared to the concentrations of TBHQ used for the other metals (copper and stainless steel). Theoretical …