bluuebunny/crossref_metadata_2025 huggingface dataset:
An Improved CNN-Based Completion Method for Power Grid Middle Platform Data
Authors: Wu Peng , Xu Mingsheng , Cheng Li
Published: February 2021

The transmission of power data would be likely to be interrupted or interfered, which results in the middle platform data missing. Missing data reconstruction plays a key role in power data processing, based on which the quality and utilization of power data have been enhanced. In traditional power data filling methods, only a single data distribution was considered, the correlation of power data in time and space was ignored. In this paper, an improved Convolutional Neural Network (CNN) method for filling power data was presented, and a CNN structure was designed. Through the unsupervised training of CNN, this method mines the correlation of data from the dimensions of time and space, and efficiently completes the missing data through the constraints of time continuity and space continuity. The completion results show that our method can fill the missing data efficiently, furthermore, experimental evaluations validate the performs of the proposed method.
A Novel Way to Realize Standardization of UAV EMA Controller
Authors: Wu Jiufeng , Yang Tao , Lyu Jianliang
Published: February 2021

UAV (Unmanned Aerial Vehicle) application is becoming wider and wider, its flight safety and performance is quite important. As one of its key components, EMA (Electronic Mechanical Actuator) plays a significant role in deciding UAV performance. In order to reduce cost, shorten design period and save human power, a novel way to realize standardization of the EMA controller is presented in this paper. Based on analysis of the typical EMA with DC (Direct Current) brush motor as its power source used in UAV, the standardization controller is designed. The generalized hardware platform is built with all the functional parts required. And then the communication protocol is made for EMA controller configuration. The upper computer software and the embedded software collaborates to conduct various controller functions. The standardization controller features modularization, combination and seriation, which is better than the traditional EMA controller for it saves cost and time. Several ground tests and flight tests prove its feasibility and validity.
Direct Yaw-moment Control with a F-TDMA Scheduler for Electric Vehicle
Authors: Cao Wanke , Liu Jizhi , He Yong
Published: February 2021

This paper proposed a new scheduling approach for direct yaw-moment control (DYC) of distributed-driven electric vehicles (EVs) over a controller area network (CAN). The insertion of the communication network makes the system a distributed control system, which leads to clock asynchrony among control system components and asynchrony-induced delays. This paper employs a flexible Time Division Multiple Access (F-TDMA) scheduler to manage the communication flows. And the stability of the close-loop system is guaranteed by using the pole placement method. The results of the simulation illustrate that the proposed method can effectively deal with the clock asynchrony problems and guarantee the stability of the system.
The future of invasive terrestrial vertebrates in Europe under climate and land-use change
Authors: Polaina Ester , Soultan Alaaeldin , Pärt Tomas , Recio Mariano R
Published: February 2021

Predicting suitable locations for invasive alien terrestrial vertebrates (IATV) under different scenarios of global change is essential for local and transboundary management aimed to prevent the spread of invasions. Using a spatial modelling approach adapted to invasive species, we identify range-shifts in suitable areas for 15 of the most harmful IATV in Europe, considering future climate and land-use changes. We predict range contractions for seven of these IATV, expansion for four, and inconclusive outputs for the rest. For most Europe, future aggregated distributions show stable or decreasing trends in total IATV richness. Still, specific regions will increase their suitability for additional IATVs, including some protected and last-of-the-wild areas. Our results are informative for early decision-making and long-term strategies to prevent negative effects of IATV. Our approach is based on publicly available data, so predictions can be revised as new data becomes available.
Variation in aboveground biomass in forests and woodlands in Tanzania along gradients in environmental conditions and human use
Authors: Requena Suarez Daniela , Rozendaal Danaë M A , De Sy Veronique , Gibbs David A , Harris Nancy L , Sexton Joseph O , Feng Min , Channan Saurabh , Zahabu Eliakimu , Silayo Dos Santos , Pekkarinen Anssi , Martius Christopher , Herold Martin
Published: February 2021

Disturbed African tropical forests and woodlands have the potential to contribute to climate change mitigation. Therefore, there is a need to understand how carbon stocks of disturbed and recovering tropical forests are determined by environmental conditions and human use. In this case study, we explore how gradients in environmental conditions and human use determine aboveground biomass (AGB) in 1958 national forest inventory (NFI) plots located in forests and woodlands in mainland Tanzania. Plots were divided into recovering forests (areas recovering from deforestation for <25years) and established forests (areas consistently defined as forests for ⩾25 years). This division, as well as the detection of year of forest establishment, was obtained through the use of dense satellite time series of forest cover probability. In decreasing order of importance, AGB in recovering forests unexpectedly decreased with water availability, increased with surrounding tree cover and time since establishment, and decreased with elevation, distance to roads, and soil phosphorus content. AGB in established forests unexpectedly decreased with water availability, increased with surrounding tree cover, and soil nitrogen content, and decreased with elevation. AGB in recovering forests increased by 0.4 Mg ha−1yr−1 during the first 20 years following establishment. Our results can serve as the basis of carbon sink estimates in African recovering tropical forests and woodlands, and aid in forest landscape restoration planning.
Experimentations on the Transmit Power of a Universal Software Radio Peripheral Using GNU Radio Framework and a Handheld RF Explorer
Authors: Ajala Sunday , Adetiba Emmanuel , Akanle Mathew B. , Obiyemi Obiseye O. , Thakur Surendra , Abolarinwa Joshua
Published: February 2021

The Universal Software Radio Peripheral (USRP) and GNU Radio framework have a wide range of applications and are actively in use for teaching, research and for practical deployment of various trending wireless technologies. In this work, we explore the relationships between the power outputs of a USRP B200 device and its operating frequencies and USRP Hardware Driver (UHD) gains. These relationships are not precisely specified on the device datasheet, thereby hindering prompt design and experimentation decisions among Software Defined and Cognitive Radio (SDCR) researchers. A general purpose handheld spectrum analyser was engaged for recording the power outputs from the USRP B200 device within an experimental testbed that was setup for this study. The B200 device was driven by a GNU radio flowgraph designed for both wired and wireless modes and running on a general purpose host computer in the testbed. The results indicate that the output power decreases while the centre frequency increases, whereas the output power increases as the UHD gain increases from 65 dB until the device reaches the saturation point at 89.9 dB. These results provide a handy toolkit for SDCR researchers and practitioners.
Moringa oleifera as natural coagulant in water treatment and production of antifungal soap
Authors: Ojewumi M.E. , Alagbe E.E. , Abinusawa A.P. , John A.N. , Taiwo S.O. , Bolade O.P.
Published: February 2021

The use of Moringa oleifera seed in water purification has reduced the use of chemical-based coagulants which is detrimental to both human and livestock. This project aimed at testing the microbial properties of M. oleifera seed oil extract on some selected pathogens (Bacterial and fungi). The oil was extracted using Soxhlet apparatus with ethanol as solvents. Gas-chromatography-mass spectrometry (GCMS) analyses were carried out for the identification of active components in the oil extract. The zone of inhibition test carried out showed that this particular plant seed oil extract has antifungal property with Candida albicans and Rizopus stolonifera with highest zone of inhibition. The raffinate was used for water purification and the oil for the production of an antifungal soap.
Knowledge management conceptual framework in Nigeria tertiary institutions
Authors: Ogunbanwo A. S. , Okesola J. O , Sheryl Buckley
Published: February 2021

Knowledge is an essential resource to academic institutions, but its management especially in the developing countries has always been very difficult. A KM model is developed in this study to manageinstitutional resources and makesame available at the right time towards enhancing academic performance. Quantitative research approach was adopted over content analysis to evaluate data obtained through the review of the past related works on KM models. The study framework is based on some established models and is integrated into the university process activities. It links institutional knowledge to capabilities and KM system to ensure best practices and promote academic performance.
Antimicrobial and Antioxidant properties of Petiveria alliacea
Authors: Olomieja A. O. , Olanrewaju I. O. , Ayo-Ajayi J. I. , Jolayemi G. E. , Daniel U. O. , Mordi R. C.
Published: February 2021

The leaf, stem and root decoctions of Petiveria alliacea (referred to as Anamu or Apacin (Guatemala), Guinea–Hen weed (English), Awogba or Ojusaju (Yoruba), kanunfari (Hausa) and Akwa-ose (Igbo) have been used as a diuretic, antispasmodic, sedative, analgesic and anti-inflammatory agents in traditional medicine. Cold maceration and Soxhlet extraction techniques were used to obtain oils from the leaf, stem and root of P. alliacea. The oils were analysed for their antimicrobial properties using brothmicrodilution technique while their antioxidant properties were determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) tests. The antimicrobial tests on the following micro-organisms Salmonella typhi, Staphylococcus aureus, Bacillus subtilis, Escherichia coli,as well as the anti-fungi test on Rhizopus sp., and Aspergillus niger, showed that the hexane and ethanol cold leaf extracts were most effective in limiting the growth of Salmonella typhi with minimum inhibitory concentration (MIC)value of 3.125 µg/mL and minimum bactericidal concentration (MBC)value of 6.25 µg/mL. The ethanol leaf extracts using Soxhlet extraction technique were most effective at MIC value of 3.125 µg/mL on Staphylococcus aureus, Escherichia coli. Likewise, the hexane and ethanolcold leaf extracts were most effective in limiting the growth of Rhizopus sp. and Aspergillus niger with MIC value of 3.125 µg/mL and minimum fungicidal concentration (MFC) value of 6.25 µg/mL.
Nanoinformatics: Opportunities and challenges in the development and delivery of healthcare products in developing countries
Authors: Nwankwo Wilson , Ukhurebor Kingsley Eghonghon
Published: February 2021

The world is witnessing sustained effects of information technologies across all works of life. Though some of these influences are markedly negative and detrimental to the socio-economic prospects and progress of the society, the positive effects are often impressive especially where they are integrated for the betterment and greater good of the larger society. One of the fastest growing technologies is nanotechnology. Nanotechnology has numerous prospects and applicability across various sectors ranging from electronics, telecommunications, agriculture and food production, biotechnology and genetics, oil prospecting and production, remote sensing, drug production, to name a few. This novel technology readily finds usefulness and several researches are ongoing, geared at developing new tools and techniques that would improve its acceptance across the concerned domains. It is this quest that has culminated into the ongoing effort in nanoinformatics, an interdisciplinary study and a subdomain of informatics simply regarded as the conscientious application of informatics tools and technologies to the analysis, design and development of systems on the broad spectrum of nanomaterials including their physicochemical and environmental characteristics as well as their interactions, interrelationships, and applications within a given domain. This paper presents a review of some opportunities for individuals, experts, and the society especially in the production of cost-effective nanotechnology-based healthcare products. Notwithstanding the aforesaid opportunities which could be harnessed and sustained in any developing country like Nigeria, this paper identifies and buttresses core challenges that could confront the adoption of good nanoinformatics methodologies. This paper concludes that a developing country (Nigeria in perspective) could benefit from nanoinformatics if there are stronger ties among the key stakeholders involved in healthcare products delivery in the society.
Performance evaluation of features for gene essentiality prediction
Authors: Aromolaran Olufemi , Oyelade Jelili , Adebiyi Ezekiel
Published: February 2021

Essential genes are subset of genes required by an organism for growth and sustenance of life and as well responsible for phenotypic changes when their activities are altered. They have been utilized as drug targets, disease control agent, etc. Essential genes have been widely identified especially in microorganisms, due to the extensive experimental studies on some of them such as Escherichia coli and Saccharomyces cerevisiae. Experimental approach has been a reliable method to identify essential genes. However, it is complex, costly, labour and time intensive. Therefore, computational approach has been developed to complement the experimental approach in order to minimize resources required for essentiality identification experiments. Machine learning approaches have been widely used to predict essential genes in model organisms using different categories of features with varying degrees of accuracy and performance. However, previous studies have not established the most important categories of features that provide the distinguishing power in machine learning essentiality predictions. Therefore, this study evaluates the discriminating strength of major categories of features used in essential gene prediction task as well as the factors responsible for effective computational prediction. Four categories of features were considered and k- fold cross-validation machine learning technique was used to build the classification model. Our results show that ontology features with an AUROC score of 0.936 has the most discriminating power to classify essential and non-essential genes. This studyconcludes that more ontology related features will further improve the performance of machine learning approach and also sensitivity, precision and AUPRC are realistic measures of performance in essentiality prediction.
Predicting Non-Newtonian Fluid Electric Submersible Pump failure using Deep Learning and Artificial Neural Network
Authors: Okoro Emmanuel E. , Sanni Samuel E. , Okigbo Amarachi , Adeyemi Fisayo , Emetere Moses E. , Obomanu Tamunotonjo
Published: February 2021

The monitoring of electric submersible pumps (ESPs) is essential for optimal petroleum artificial lifting operations. Most ESP research are aimed at operation improvement and optimization of the centrifuge multi-stage pump motor and the load that the pump has to discharge which is a function of the pumps mechanical properties and characteristics, liquid compositions, pressure and temperature. ESPs failure often lead to oil production losses or “oil deferment” which affects revenue for all the parties involved. Also, pulling the ESP out of the wellbore of interest, requires mobilization of a rig because it is installed several hundred meters down the wellbore. To prevent these loses, a predictive approach is needed to avert these scenarios. In the current decade, machine learning algorithms studies have spurred real- time technologies research interest due to their abilities to predict future outcomes using already existing data sets. This study presents a predictive approach for Electric Submersible Pump failure during artificial lift operations. The study creates an “algorithm” that helps to predict via Machine learning, the failure of an ESP with the assumption that failure is usually caused by pressure build-ups. A deep learning model for predicting ESP failure was proposed and artificial neural network was used in developing the suggested model. Based on the outcomes of this study, it can be concluded that the selected AI algorithm and its characteristics, are suitable for applications in detecting ESP failure before it happens using upstream-data.
Development of PIC18F4431 microcontroller controlled air conditioning system
Authors: Sheu Akeem Lawal , Adagunodo Theophilus Aanuoluwa , Oladejo Olagoke Peter , Omeje Maxwell
Published: February 2021

The aspiration for high performance industrial applications increases owing to advance in the field of power electronics. This contributed to swift developments in digital motor control technology. High energy consumption and poor efficiency are major challenges of motor driven appliances. These appliances need cost-effective solutions controlled drive that improves process precision, cuts operating costs and facilitates less energy. The goal of this research is to develop feasible motor control air conditioning system. The developed system describes the optimization and designing of a microcontroller controlled drive with speed sensing. It is PIC18F4431 based microcontroller primarily for motor control applications. This study focuses on speed control of induction motor using PIC microcontroller through PWM technique. The result of the research indicates that at the 5% air flow rate, the air conditioner without the drive consumed about 87% energy whereas the microcontroller based drive only consumed 20% energy at the same flow rate. This indicated the energy saving of about 67% by the air conditioner with the adoption of PIC18F4431 microcontroller controlled drive.
Big data analytics: A single window IoT-enabled climate variability system for all-year-round vegetable cultivation
Authors: Nwankwo Wilson , Ukhurebor Kingsley Eghonghon
Published: February 2021

Vegetables constitute a major food source with huge nutritional values as well as major source of income. The cultivation of vegetables is dictated by climate and seasonal changes across Nigeria. Edo State lies within the South of Nigeria and enjoys the two popular seasons (rainy and dry) like many other parts of the country. However, the variability in soil distribution and weather conditions across different locations is a determining factor as to the category of not just vegetables to grow but other crops. In this paper, Edo state is used as a flagship project for its diverse potentials and uniqueness in respect of known variability in soil and weather conditions. The State is divided into three geo-referenced agricultural districts. A prototype system is proposed to provide vegetable farmers with real-time information on vegetablefarming requirements. The proposed system is an Internet of things (IoT)-enabled climate variability system with interfaces to popular mobile networks, existing Geographical Information System (GIS) in the State, and remote sensing stations respectively. Each geo-referenced point is a nexus to areas with similar weather variability and soil distribution. Historical data is collected from the existing GIS and a provision is made to constantly enrich the historical data with new information from the geo-referenced points including crops grown, trends in cultivation, queries from farmers, etc. The information generated from the geo-referenced locations are routed via GPS to the central analytics server in the cloud and appropriate algorithms are used to carry out data analysis for real-time prediction and messages to farmers through the Internet and Short Message Services (SMS). With this system, it is submitted that subsistent and mechanized farmers would benefit through the guidance of an analytics system thereby boosting vegetablefarming regardless of the season of the year.
Design and testing of an air battery
Authors: Oguntosin Victoria , Akindele Ayoola
Published: February 2021

In this paper, an air battery is studied, discussed, implemented and deployed; the potential applications of air batteries in general are also discussed in detail. An electrochemical battery runs out when all the chemicals inside have finished the current-releasing chemical reactions. In this work, an air battery system is designed and studied using Sodium Chloride (NaCl) and Caustic Potash (KOH) electrolytic solution. The battery life of the designed air battery system is studied in terms of voltage capacity for a period of 4 weeks and 4 days (750 hours) for two air batteries connected in series. As the electrolytic chemicals are being used up when the battery is in operation, it was observed that voltage rating degraded over time even when the battery system is not connected to a load. From the results, an air battery with KOHelectrolytic solution produced a higher voltage compared with NaCl electrolytic solution
Construction of a Mobile Frequency Modulation Transmitter
Authors: Usikalu Mojisola R. , Oyeniran Fumbi T. , Ayara Williams A. , Babarimisa Idowu I. , Obafemi Leke N.
Published: February 2021

A Frequency Modulation (FM) transmitter is an electronic device that produces radio waves with the aid of an antenna. The transmitter generates radio frequency alternating current, that is applied to the antenna. When the antenna is excited by the alternating current, the antenna begins to radiate radio waves by varying the frequency of the radio signal. The transmitter is a Very High Frequency (VHF) Colpitts oscillator capable of transmitting sound to standard FM receiver fitted with a capacitor microphone which picks weak sound signals. This design was achieved using: transistors, resistors, inductors and capacitors. A transmission frequency of ± 5% 100 MHz was used and transmitted up to a distance of 5 metres. The testing of the transmitter was carried out by powering it using a 9 V DC battery and tuning a suitable FM receiver to the transmission frequency of the constructed transmitter. A transmission distance of 5 metres was achieved therefore making it possible to use the transmitter as a portable cordless microphone used for public address (P.A.) systems. The achieved fixed frequency of transmission 56.4 MHz, away from all other radio stations transmission frequencies. This gives the best range and with the least of interferences. With increased power, the range can easily be extended.
Arduino Based Security System using Passive Infrared (PIR) Motion Sensor
Authors: Akinwumi S. A , Ezenwosu A. C , Omotosho T. V , Adewoyin O. O , Adagunodo T. A , Oyeyemi K. D
Published: February 2021

Technological advancements are so fast as of now to make individuals need consistently to be inventive and trigger to make something new which can be applied and can utilize rapidly and for all purposes and control from close range and distance. There has been drastic increase in theft and burglary, robbing of houses, stores, shops and banks etc. This has also increased the number of violence and crime related activities which occur on a daily basis, in which lots of lives and monetary loses have been recorded. This research focuses on how to configure a simple home security framework using a PIR sensor(Passive Infra-Red) in light of a microcontroller. This safety will work if the PIR (Passive Infra-Red) sensor recognizes any individual that would not like to go into the house, and afterward themicro-controller process and instructs a mobile phone to send an alarm signal in theform of Short Message Service (SMS). After the program was successfully uploaded to the circuit, a test was carried out to determine if the PIR worked perfectly and it came out with positive results as it detected motion. As a motion was detected, the sensor became active, therefore gave a signal to the Arduino which gave an output signal to the led and thereby making the buzzer to sound an alarming noise.
Prediction of Lattice Constants of some Transition Metal Nitrides using Different Functionals and Pseudo-potentials
Authors: Oyewande O. E. , Atsue T. , Ogunniranye I. B. , Usikalu M.
Published: February 2021

Properties of materials are best analyzed when lattice parameters of such compounds of materials are predicted accurately. In density functional theory prediction of lattice parameters, density functionals play important role in obtaining accurate values. In this study, density functional theory was used to investigate accurate prediction of lattice parameters of some transition metal nitrides. Local Density Approximation (LDA) and Generalized Gradient Approximation of Perdew-Burke-Ernzerhof revised for solids (GGA-PBEsol) functionals combined with ultrasoft and projector augmented wave (PAW) pseudo-potentials were used for the investigation. The results indicated that GGA-PBEsol functional with PAW pseudo-potential performed better in predicting lattice parameters of these compounds. ForFeN compound, the calculated lattice parameter with GGA-PBEsol functional and PAW pseudo-potential was 4.232 Å compared with the experimental values of 4.307 Å and 4.296 Å corresponding to a little underestimation of about 1.74% and 1.49% respectively. Ultrasoft pseudo-potential of GGA-PBEsol functional and LDA functional with the two pseudo-potentials overestimated the lattice parameters for over 5%. It was concluded that, for the functionals and pseudo-potentials considered, GGA-PBEsol with PAW pseudo-potential may be a very good choice for prediction of lattice parameters of binary compounds with transition metals.
Analytic ground state energy and wave function of a quantum system in an exponential-form anharmonic interaction potential
Authors: Babalola Israel B , Oyewande Oluwole E , Latok Idowu H , Olawole Olukunle C
Published: February 2021

An anharmonic oscillator with a perturbed quadratic potential which is coupled with an exponential term is being investigated in this paper by isolating an anharmonic oscillator interaction potential from the actual interaction experienced by the quantum system studied, and using standard perturbative techniques. The anharmonic potential considered is of interest because of its usefulness in the study of non-centrosymmetric materials which have applications in piezoelectricity. The ground state energy eigenvalue and its associated eigenstates were calculated for the quantum system using an analytical approach. Results obtained are compared to those of quantised harmonic oscillator to show the effect of the perturbation.
Humidity and Moisture Degradation of Perovskite Material in Solar Cells: Effects on Efficiency
Authors: Ogunniran Kehinde O. , Martins Nlebemuo T.
Published: February 2021

Humidity is the concentration of water vapor in air and moisture is the relatively small amount of water in a material. The two both have positive and negative influences on the development of perovskite solar cells. It is becoming increasingly clear that the effects of humidity will be a key factor to drive the commercialization of this promising new solar cell technology. The interface amid MAPbI3 and water vapor has been explored and studied by different researchers through optical absorption spectrometry, morphological and crystallographic studies. These studies have helped to demystify the complex interactions going on in the system. A particular study reported the possibility of a perovskite molecule forming a hydrate compound when exposed to H2O vapor in the dark coupled with its dissolution of MAPbI3. Some researchers have said that to improve the stability of this device in moisture. The device must be studied as a whole system rather than studying just the individual components. This review paper explores the works done on perovskite stability highlighting how humidity and moisture affect both the preparation and performance of perovskite material and perovskite solar cell.
Emissions of CO and SO2 from solvent extraction treatment of used lubricant
Authors: Oladimeji Temitayo E. , Sonibare Jacob A. , Omoleye James A. , Emetere Moses E. , Odunlami Olayemi A.
Published: February 2021

Emissions fromused lubricant could have adverse effect on man and its environment due to the presence of degraded additives and contaminants. Different treatment methodshas been developed with few check on its pollution aspect. This study investigated the emissions of two major criteria pollutants - carbon monoxide (CO) and sulphur dioxide (SO2) from the solvent extraction treatment of used lubricant. CO was found to be the highest emitting pollutant with mean emission concentration of 85.85 mg/m3 which has exceeded the set NAQS standard while SO2 falls within the standard limit. Therefore, there is a great need to give attention to the control of CO emissions around the treatment plant. However, CO emission can be controlled by employing a CO converter to convert the poisonous gas to a less poisonous gas or substituting the existing process in solvent extraction with a more environmentally friendly one.
Analysis of entropy and effect of surface dynamics on photovoltaic performance
Authors: Abodunrin T.J. , Usikalu M.R. , Emetere M.E. , Yenus Z. , Kotsedi C. , Maaza M.
Published: February 2021

We investigate the influences of photoanode on light scattering and absorption in a dye-sensitized solar cell (DSSC). N719 dye on a monolayer anode of TiO2 film and ZnO film, are compared in terms of their photovoltaic conversion efficiency. Doctor blade application and high temperature sintering of photoanode assemblage on indium doped tin oxide glass was adopted for preparation of the two photoanodes. The optical density of the interfacial layer relative to the photogenerated carriers is determined by absorption of ionic electrolytes. The outcome obtained with different photosensitizing effect of organic T.danielliimolecules on DSSCs showed a wide disparity, the highest Voc was recorded with Br− with 500 mV and 79 mV respectively for TiO2 and ZnO photoanode respectively. Three important morphological characterization techniques were used, scanning electron microscopy (SEM) with energy dispersive spectrum (EDS), Electron shell occupancy and Entropy were discussed in detail with respect to their photoelectric performance, the best Iscwas 0.035 mA with Br− on TiO2 attributable to a large optical density, achieved from ratio of area of molecular coverage of nanoparticle film. Scanning electron microscopy (SEM) revealed a structure consisting of direct and ordered paths for photogenerated carriers to the collecting electrodes, the Pmaxresult reported was 36.54 mW with Br− from TiO2.
First principles assessment of the performance of pseudopotentials on cubic phase MAPbI3 perovskite using PBE functional
Authors: Micheal Emeka , Oyewande O.E. , Adegboyega Oluwasogo A. , Akinyemi M.L.
Published: February 2021

Perovskites have shown to be an excellent material for photovoltaics applications, due to its opto-electronic properties and low cost of fabrication. This paper is focused on assessing the performance of different pseudopotentialsinpredicting some opto-electronic properties of methyl ammonium lead iodide (MAPbI3) cubic phase perovskite in comparison with experimental results using ab initio density functional theory (DFT) as implemented in Quantum-espresso software. The pseudopotentials used were; Projector Augmented Wave (PAW) and Ultra-soft (US). From the study, it was observed that Perdew Burke Enzerhof (PBE) functional with Ultra-softpseudo potential gave a lattice constant of 6.20 A
0 while the mixed pseudopotentials gave a band gap value of 1.64 eV, which were in closer agreement with experimental results of 6.27 A
0 and 1.60 eV respectively. These simulated results suggested that PBE-US pseudopotentials give a better lattice constant estimate, while the mixed pseudopotentials give a better estimate of the band gap of cubic phase MAPbI3 perovskite.
Monte-Carlo Study of Ion-Sputtering Parameters and Ab-Initio Calculations of Selected Perovskites for Solar-Powered Electricity
Authors: Oyewande O. E , Akinpelu A
Published: February 2021

Attributable to efficiencies as high as 25.2%, organic inorganic hybrid perovskite has become the quickest developing solartechnology, rivalling the conventional photovoltaic technology. Although, they are unique and remarkable, stability concern and toxic behaviour of perovskites impedemass production. With this impetusofrealizing a non-toxic perovskite, a new approach was proposed by performing Monte Carlo simulations. In this paper, this approach was further studied with an First principlesinvestigations using the plane-wave pseudopotential method within the density functional theory (DFT) as employed in Quantum ESPRESSO (QE) software package. Mechanical and electronic properties of CH3NH3PbBr3, CH3NH3SnBr3, CH3NH3SnI3, and CH3NH3PbI3, perovskites were investigated. Lattice constants were calculated to understand the mechanical properties, while band gaps were calculated to shed more light on their electronic properties. Our resultswere compared with the experimental and theoretical values and found a good agreement between them. These indicated that the two materials were remarkably similar and that Sn was a good substitute for Pb in solar cell perovskite materials.
Capital Flight and Poverty Reduction in Nigeria
Authors: Alejo A. , Aremu J. , Matthew O.A. , Owolabi O.A. , Okorie U.E. , Osabuohien R. A.
Published: February 2021

The literature from development economics asserted that two major spillover effects of the prevalence of capital flight and low rate of investment in developing economies are the persistent increase in unemployment and absolute poverty. Since an increase in the poverty rate can be viewed in terms of forgone private and public investment in some poverty reducing programmes like education, health intervention and job creation. Thus, this study investigates the interplay between capital flight and poverty reduction in Nigeria using secondary data covering the period between 1981 and 2017. This study employs the Augmented Dickey Fuller (ADF) test; Philip Perron (PP) test; Kwiatkowski, Phillips, Schmidt and Shin’s (KPSS) all forms of unit root tests; Johansen test for co-integration and Dynamic Ordinary Least Square (DOLS) for long run estimates. The study found that an increase in poverty level in the country would be preceded by raising capital flight coupled with increasing dependence ratio and decline in economic growth rate. In this scenario, the effect of a single digit economic growth is dissipated once the circle continues unabated. Consequently, this study recommends that the Federal Government of Nigeria through the relevant financial authorities should enforce regulation against illicit flow of capital and prosecute offenders. The Federal Government must be seen to support the agency efforts against illicit flow in the country.
Climate Change Mitigation Strategies: A Case of Manufacturing Companies in Ota, Nigeria
Authors: Tunji-Olayeni P.F. , Osabuohien E.S. , Oluwatobi S.O. , Babajide A.A. , Adeleye B.N. , Agboola M.G.
Published: February 2021

Carbon emissions (C02) from manufacturing companies contribute significantly to the volume of atmospheric Greenhouse Gases (GHGs) that trigger climate change. Mitigating climate change has become necessary because of the effects it has on social, economic and environmental outcomes. The minutest action taken against climate change can reduce its devastating impacts. Hence, this study assesses the strategies used by manufacturing companies in mitigating climate change. The study location is Ota, Nigeria. In this paper, a quantitative research approach was adopted with questionnaires distributed to participants at a climate change workshop, which is analysed using statistical techniques. The results show, among others, that all the respondents are aware of climate change and the most common source of climate change knowledge is the mass media. Moreover, most of the respondents describe climate change as a rise in global temperatures. Waste reduction, waste recycling, and waste reuse are the most common climate change mitigation strategies adopted by the manufacturing companies. Other mitigation strategies include: use of energy-saving bulbs in offices and factories and switching off electrical appliances when not in use. Although the findings indicate that the manufacturing companies are taking some steps to mitigate climate change, a lot still has to be done in reducing carbon emission levels, particularly during the manufacturing process. It is also essential that manufacturers use renewable energy sources as alternative power instead of diesel generators so that the volume of atmospheric carbon in the region can be reduced considerably. The role of government in driving emission reduction is also emphasised. The study provides baseline data that can be used in the development and implementation of policies on regional climate change mitigation strategies.
Climate Change Impacts on Environment: Human Displacement and Social Conflicts in Nigeria
Authors: Olagunju T.E. , Adewoye S.O. , Adewoye A.O. , Opasola O.A.
Published: February 2021

In northern Nigeria, drought and desertification have grossly affected water available and land carrying capacity for both pastureland and farmlands. Hence, the northerners, particularly, the youthinevitably migrate to the south for greener pasture for themselves and the animals. Most of these youths are uneducated and not skilled to secure employment, they, therefore, become an instrument in the hands of religious bigotry. This climatic change can also result in a rise in sea level, thereby increasing the flood events especially, in Nigeria’s lowlands. These changes have not only caused fierce conflicts buthave additionally brought about the death of thousands and rendered many homeless. The Nigeria Middle Belt has been the region most impacted by violent death resulting from land resource scarcity. The conflict has ensued between contrasting groups when essential resources become scarcely limited. Northern Nigeria accounts for 68% of every fiercedeath due to the issues of land between farmers and pastoralists in 2006 and 2014, a figure not half the reported cases in 2018 alone. The inadequacies in the Nigerian adaptation efforts to its dwindling climate could be attributed to corruption, institutional shortcomings and political will predisposes the country to more dangers of environmental change impacts. Therefore, climate change mitigating and adaptation measures, unbiased and efficient conflict management strategies, as well as the improved condition of living must be ensured by the government stakeholders to safecurrent and future generations of the country from havocs due to climate impacts.
MILLENIAL OUTLOOK ON POVERTY AND ITS CONSEQUENCE ON HUMAN SECURITY IN NIGERIA
Authors: Iheagwam Nelson Chidiebere , Iheagwam Franklyn Nonso , Oni Samuel Olorunmaiye
Published: February 2021

This research is addressesmillennial outlook on poverty in contemporary Nigeria and its impact on human security. The objectives of this study were to examine the causes of poverty, effect of poverty on human security and how poverty can be curbed in Nigeriafrom year 2000 - 2018. The data required for this study were acquired using secondary data sources. Two propositions were drawn from this study and content analysis was used to prove them. The result showedpoverty had an effect on human security in Nigeria as well as being the root of many human security problems. Nigerian state must therefore deal with the issue of poverty in its soil concomitantly bettering human security.
Seismically Determined Acoustic Gruneisen Parameter in the Earth’s core
Authors: Ogunseye T. T. , Popoola O. I. , Awe O.E.
Published: February 2021

The determination of the thermodynamic properties of the Earth’s core requires the computation of acoustic Grüneisen parameter of solids at the prevailing pressure and temperature of the Earth’s core. The acoustic Grüneisen parameter, γa
, of the Earth’s core were determined seismically from the velocity and density profiles. In this paper, the seismic data from the Preliminary Reference Earth Model (PREM) were used in computing the acoustic Grüneisen parameter γa
at each depth of the Earth’s core. The thermal derivatives

d

(
I
n

V

S

)

d

(
I
n

V

ρ

)

and

d

(
I
n

V

P

)

d

(
I
n

V

ρ

)

which defines the modes from the velocity and density profiles were used to determine the values of the acoustic Grüneisen parameter. The result for the outer core showed that the average γa
is 1.53 which is found to be consistent with result obtained from previous studies
Compatibility of Electromagnetic (EM) Method and Geospatial Analysis for Identifying the Vulnerable Building Zonation in Coastline Area of Ado-Odo Ota, Ogun State, Nigeria
Authors: Maxwell Omeje , Adewoyin Olusegun O. , Joel Emmanuel S. , Adagunodo Theophilus A. , Akinwumi Sayo A. , Omeje Uchechukwu A. , Arijaje Theophilus E. , Danie Ozieme Arinze , Akinpelu Akinwumi , Kwushue Daniel , Sani Victor , Folarin Ife , Victor Belo , Bello Oluwaseyi O.
Published: February 2021

Collapsing of building incidents have been reported all over the world and seems to be commonespecially in sedimentary terrain of the coastal plain sand of Ado-Odo Ota which has the same subsurface features as the Lagos that experience regular building collapse. This building collapse is attributed to several causes. The reasons that have been identified, have added little or no impact on reducing this environmental disaster. This study presents the strength of emerging and existing geophysical tools for near-surface structural studies. The aim is to reveal the recent technical development on improving field surveys to minimize building collapse. Data acquisition using electromagnetic (EM) methods which are known for fast mapping of near-surface spatial variation as well as obtaining the subsurface vertical variation in electrical conductivity was adopted. The acquired spatial and attribute data was introduced in a GIS environment with different thematic vectors/layers created by digitizing the satellite image of the study area. The GIS digitizing was to geographically trace the acquired data with accurate coordinates from the obtained EM field data with the thematic layer representing the features such as weak zone and competence zones that can hold buildings. A transverse was taken in a strategic positions considering the regional features with 10 m spacing to cover the marked stations. It revealed the layer depths range from 0.37 to 1.64 m with the much competence layer found to be about 1.64 mbeyond which may be the thick clay Ilaro formation that underlies the recent formation. The weathered shear zone at the depth of 0.37 m may be the recent lithoral deposits which is geotechnically and geologicallyunstable and proximity to active faults of ruptured geomorphology of the building zonation.
Significance of using electromagnetic (EM) method for groundwater investigation in Sedimentary and Basement terrains: a review
Authors: Maxwell Omeje , Oni Olubukola A. , Adewoyin Olusegun O. , Joel Emmanuel S. , Adagunodo Theophilus A. , Akinwumi Sayo A. , Omeje Uchechukwu A. , Arijaje Theophilus E. , Akinpelu Akinwumi
Published: February 2021

This review article briefly explores the significance of electromagnetic method among other methods used in groundwater investigation. Groundwater investigation can be carried out using various methods such as seismic, magnetic, electromagnetic (EM), electrical resistivity, gravity, remote sensing. Each with its peculiar implication. This paper discusses the effectiveness of EM in detail subsurface investigation for groundwater exploration through an extensive review of the literature. Relevant literatures within the last three years were considered to understand the groundwater features using the EM method over other techniques. Studies using other methods were also examined to compare their reliability in groundwater studies to EM method. This study discovered that the EM method is cheaper, faster and of higher precision in identifying groundwater bearing formation and possible structural control of which the rest technique do not posess such attribute. On this note, there should be a growing interest in the use of EM techniques for groundwater mapping, which gives credible and classification of structural features of both basement and sedimentary terrain groundwater characteristics.
Equality of orders of a set of integers modulo a prime
Authors: Järviniemi Olli
Published: February 2021

For finitely generated subgroups

W
1

,
…
,

W
t

W_1, \ldots , W_t

of

Q

×

\mathbb {Q}^{\times }

, integers

k
1

,
…
,

k
t

k_1, \ldots , k_t

, a Galois extension

F
F

of

Q

\mathbb {Q}

and a union of conjugacy classes

C
⊂

G
a
l

(
F

/

Q

)

C \subset \mathrm {Gal}(F/\mathbb {Q})

, we develop methods for determining if there exist infinitely many primes

p
p

such that the index of the reduction of

W
i

W_i

modulo

p
p

divides

k
i

k_i

and the Artin symbol of

p
p

on

F
F

is contained in

C
C

. The results are a multivariable generalization of H.W. Lenstra’s work. We present several applications, including a characterization of all integers

a
1

,
…
,

a
n

a_1, \ldots , a_n

such that

o
r
d

p

(

a
1

)
=
…
=

o
r
d

p

(

a
n

)

\mathrm {ord}_p(a_1) = \ldots = \mathrm {ord}_p(a_n)

for infinitely many primes

p
p

. The obtained results are conditional to a generalization of the Riemann hypothesis.
On a class of Hessian type equations on Riemannian manifolds
Authors: Jiao Heming , Liu Jinxuan
Published: February 2021

In this paper, we consider a class of Hessian type equations which include the

(
n
−
1
)

(n-1)

Monge-Ampère equation on Riemannian manifolds. The a priori

C
2

C^2

estimates and the existence of solutions are established.
Parabolic and elliptic equations with singular or degenerate coefficients: The Dirichlet problem
Authors: Dong Hongjie , Phan Tuoc
Published: February 2021

We consider the Dirichlet problem for a class of elliptic and parabolic equations in the upper-half space

R

+
d

\mathbb {R}^d_+

, where the coefficients are the product of

x
d
α

,
α
∈
(
−
∞
,
1
)
,

x_d^\alpha , \alpha \in (-\infty , 1),

and a bounded uniformly elliptic matrix of coefficients. Thus, the coefficients are singular or degenerate near the boundary

{

x
d

=
0
}

\{x_d =0\}

and they may not be locally integrable. The novelty of the work is that we find proper weights under which the existence, uniqueness, and regularity of solutions in Sobolev spaces are established. These results appear to be the first of their kind and are new even if the coefficients are constant. They are also readily extended to systems of equations.
Rpgrip1l controls ciliary gating by ensuring the proper amount of Cep290 at the vertebrate transition zone
Authors: Wiegering Antonia , Dildrop Renate , Vesque Christine , Khanna Hemant , Schneider-Maunoury Sylvie , Gerhardt Christoph
Published: February 2021

The study provided by Wiegering et al. investigates molecular mechanisms underlying ciliary entry and exit of proteins. It demonstrates that Rpgrip1l governs ciliary gating by controlling the amount of Cep290 at the vertebrate transition zone.