Nigerian Journal of Technological Development最新文献_第9页

Comparison of Theoretical Disc and Point Source Profiles with Actual-Melt Source Profile in Conduction Welding 传导焊中理论盘源、点源轮廓与实际熔体源轮廓的比较

Nigerian Journal of Technological Development Pub Date : 2022-09-23 DOI: 10.4314/njtd.v19i3.8

W. Ayoola, W. Suder, S. Williams

引用次数: 0

Assessment of Carbon Dioxide Storage Capacity of Selected Aquifers in ‘J’ Field, West Africa 西非“J”油田部分含水层二氧化碳储存能力评价

Nigerian Journal of Technological Development Pub Date : 2022-09-23 DOI: 10.4314/njtd.v19i3.4

W. Raji, S. Bello, T. O. Adeoye

{"title":"Assessment of Carbon Dioxide Storage Capacity of Selected Aquifers in ‘J’ Field, West Africa","authors":"W. Raji, S. Bello, T. O. Adeoye","doi":"10.4314/njtd.v19i3.4","DOIUrl":"https://doi.org/10.4314/njtd.v19i3.4","url":null,"abstract":"combination of seismic data and petrophysical logs from five wells acquired in ‘J’ Field, Niger Delta, Nigeria, have been analyzed to assess the carbon dioxide (CO2) storage potential of some saline aquifers in ‘J’ field. The study aims to evaluate the volume of CO2 that can be potentially stored in the aquifers and the risk of CO2 leakages in the storage. The sand aquifers were correlated across the five wells to evaluate their thicknesses and lateral extent. Porosity, permeability, formation water resistivity, and net sand thickness were estimated in the different wells. The Horizons corresponding to the top of the aquifers was mapped, and time and depth structured maps were generated for structural analysis and volumetric estimations. The risk of CO2 leakages through sealing layers (cap rocks) was evaluated in terms of caprock integrity and pore pressure sealing mechanism. Results of the study showed that four aquifers, namely, L20, N30, M40, and P50, are laterally extensive across the five wells and have thicknesses that range from 14 to 352 m. The individual CO2 storage capacity of L20, M30, N40, and P50 was estimated to be 6.97×1010, 1.48×1010, 7.78×109 and 1.49×1010 tons, respectively. The combined aquifer storage capacity was estimated to be 1.07×1011 tons. The sealing layers have low risk of CO2 leakages. The study concluded that the aquifers have good potential for CO2 storage and low risk of leakages. The study ranked L20 as the best among the four aquifers.","PeriodicalId":31273,"journal":{"name":"Nigerian Journal of Technological Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41482013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of an American Sign Language Recognition System using Canny Edge and Histogram of Oriented Gradient 基于Canny边缘和梯度直方图的美国手语识别系统的开发

Nigerian Journal of Technological Development Pub Date : 2022-09-23 DOI: 10.4314/njtd.v19i3.2

I. Adeyanju, O. O. Bello, M. A. Azeez

{"title":"Development of an American Sign Language Recognition System using Canny Edge and Histogram of Oriented Gradient","authors":"I. Adeyanju, O. O. Bello, M. A. Azeez","doi":"10.4314/njtd.v19i3.2","DOIUrl":"https://doi.org/10.4314/njtd.v19i3.2","url":null,"abstract":"Sign language is used by people who have hearing and speaking difficulties, but not understood by many without these difficulties. Therefore, sign language recognition systems are developed to aid communication between hearing impaired people and others. This paper developed a static American Sign Language Recognition (ASLR) system using canny-edge and histogram of oriented gradient (HOG) for feature extraction with K-Nearest Neighbour (K-NN) as classifier. The sign language image datasets used consist of English alphabets from both Massey University and Kaggle, and numbers (0-9) from Massey University. Median filter was used to remove noise after images were converted to grayscale. Otsu algorithm was used for segmentation while edges in the images were preserved using canny edge detection technique with HOG parameters tuning to obtain feature vectors. The extracted features were used by K-NN for classification. An average recognition accuracy and computational testing time of 97.6% and 0.39s respectively were obtained based on experiments with the Massey University dataset. Similarly, an average recognition accuracy and computational testing time of 99.0% and 0.43s respectively were obtained based on experiments with the Kaggle dataset. The developed system successfully recognized static English alphabets and numbers and outperformed some existing systems.","PeriodicalId":31273,"journal":{"name":"Nigerian Journal of Technological Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43333752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Building Energy Simulation Model Application to Greenhouse Microclimate, Covering Material and Thermal Blanket Modelling: A Review 建筑能量模拟模型在温室小气候、覆盖材料和保温毯建模中的应用综述

Nigerian Journal of Technological Development Pub Date : 2022-09-23 DOI: 10.4314/njtd.v19i3.10

T. D. Akpenpuun, Q. O. Ogunlowo, A. Rabiu, M. A. Adesanya, W. Na, M. Omobowale, Y. Mijinyawa, H. W. Lee

{"title":"Building Energy Simulation Model Application to Greenhouse Microclimate, Covering Material and Thermal Blanket Modelling: A Review","authors":"T. D. Akpenpuun, Q. O. Ogunlowo, A. Rabiu, M. A. Adesanya, W. Na, M. Omobowale, Y. Mijinyawa, H. W. Lee","doi":"10.4314/njtd.v19i3.10","DOIUrl":"https://doi.org/10.4314/njtd.v19i3.10","url":null,"abstract":"This review documents the present knowledge and knowledge gap in applying building energy simulation (BES) dynamic models to greenhouses. The focus of this review is to compile the literature on the BES dynamic model of greenhouse microclimate, covering materials, energy requirements and thermal blankets using the Transient System Simulation version 18 (TRNSYS 18) software. Fifty-two journal articles, mostly Science Citation Index (SCI) and Scopus index journals, on BES development and simulation of greenhouse microclimate, greenhouse energy requirement, covering materials and thermal blankets were reviewed. These researchers sought to optimise greenhouse crop production. The main features of the TRNSYS 18 software for BES development are outlined; each research consulted for this review successfully developed, simulated and validated its BES. However, none of these developed models included the vapour pressure deficit (VPD) as a greenhouse microclimate factor, an essential climate parameter. In conclusion, this study demonstrates that applying a BES developed using TRNSYS has excellent potential to optimise greenhouse crop production and help adapt appropriate climate control strategies and energy-saving techniques. However, it is recommended to include VPD in future BES model development.","PeriodicalId":31273,"journal":{"name":"Nigerian Journal of Technological Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49121221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Assessment of Nigerian Calcium Bentonite as Cement Replacement for Shallow depth Oil Well Cementing Operation 尼日利亚钙膨润土作为浅层油井固井水泥替代物的评价

Nigerian Journal of Technological Development Pub Date : 2022-09-23 DOI: 10.4314/njtd.v19i3.7

A. Arinkoola, S. Alagbe, K. Salam, B. M. Ajagbe, I. Akinwole

引用次数: 1

Impact, Mitigation Strategies, and Future Possibilities of Nigerian Municipal Solid Waste Leachate Management Practices: A Review 尼日利亚城市固体废物渗滤液管理做法的影响、缓解战略和未来可能性:综述

Nigerian Journal of Technological Development Pub Date : 2022-09-23 DOI: 10.4314/njtd.v19i3.1

A. Ishaq, M. I. M. Said, S. Azman, M. Abdulwahab, M. Alfa

{"title":"Impact, Mitigation Strategies, and Future Possibilities of Nigerian Municipal Solid Waste Leachate Management Practices: A Review","authors":"A. Ishaq, M. I. M. Said, S. Azman, M. Abdulwahab, M. Alfa","doi":"10.4314/njtd.v19i3.1","DOIUrl":"https://doi.org/10.4314/njtd.v19i3.1","url":null,"abstract":"Landfills and solid waste disposal facilities have historically been the most common point sources of pollution with the potential to release contamination leachate plumes into the environment. Waste disposal is one of the biggest problems that the world is facing. In man’s everyday life, he produces waste materials which, if not properly managed, can affect health and environment. The seepage of landfill leachate into groundwater tables and aquifer systems significantly creates a possible danger and threat to human health and environment at large and remains a subject of concern in Nigeria and other parts of the world. This paper provides a review of existing approaches to leachate treatment in Nigeria and current practices across the globe, depicts the impact on environmental implications, documented previous findings, challenges and mitigation measures, and future perspectives of landfill leachate management in Nigeria, and compares with global practice of leachate management. In Nigeria, there are only a few standard techniques of landfill leachate treatment. This resulted in severe environmental impacts that threaten human life, especially in the north-eastern part of the country. Vector-borne and water-related illnesses such as cholera, Dengue, Diarrhoea, Trachoma, typhoid, malaria etc, have become a major source of concern resulting from the leaching effect from landfills. Advanced treatment methods, including membrane filtration, trickling filters, and Batch and Sequencing-Batch Reactors (SBR) are used in some of the cities and private organizations in Nigeria. Most researchers in Nigeria have stressed the necessity to utilise efficient, cost-effective technology in landfill wastewater treatment. Despite this, landfill leachate has continued to have severe effects in Nigeria and the situation seems to be escalating, requiring further study.","PeriodicalId":31273,"journal":{"name":"Nigerian Journal of Technological Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45782853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Improved Electrical Conductivity and Strength of α-Al-Carbon Nanotubes Blended with Silver Nanoparticles Composites α-Al碳纳米管与银纳米粒子复合材料的导电性和强度的改善

Nigerian Journal of Technological Development Pub Date : 2022-09-23 DOI: 10.4314/njtd.v19i3.9

V. Aigbodion

引用次数: 0

Study of the Effect of Quenchants on the Machinability of Heat Treated Mild-Steel 淬火液对热处理软钢可加工性影响的研究

Nigerian Journal of Technological Development Pub Date : 2022-09-23 DOI: 10.4314/njtd.v19i3.5

T. Ogedengbe, T. Adeyi, O. Ajao, O. A. Ileoye

{"title":"Study of the Effect of Quenchants on the Machinability of Heat Treated Mild-Steel","authors":"T. Ogedengbe, T. Adeyi, O. Ajao, O. A. Ileoye","doi":"10.4314/njtd.v19i3.5","DOIUrl":"https://doi.org/10.4314/njtd.v19i3.5","url":null,"abstract":"Heat treated steels that are quenched rapidly show an increase in hardness and toughness but also show an increase in brittleness which could lead to a higher surface roughness and low material removal rate while machining. Hence, the choice of quenchants has a significant effect on the hardness of low carbon steels. In this research work, the effect of some selected quenchants on the mechanical properties of heat treated and machined mild steel was investigated. Four samples of the carbon steel rods were furnace heated at 8500C and quenched with water, molten salt, potash alum and used engine oil. Central Composite Designs of Design Expert version 12 was used to plan the experiment. Machining factors used were, speed (100-450 rpm), feed rate (0.01-0.03 mm/rev), depth of cut (1-2mm). Surface roughness and material removal rate as well as the results of quenchant characterization were the responses studied. The favored quenchant was oil with the lowest surface roughness, hardness and material removal rate of 0.33μm and 187.78BHN and 0.020133mm3/min respectively. This is because the use of oil resulted in the highest reduction in surface roughness and enhanced material removal rate.","PeriodicalId":31273,"journal":{"name":"Nigerian Journal of Technological Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45826155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Impacts of Covid-19 Lockdown on Concentration Levels of Traffic-Related Air Pollutants in Ibadan -a West African City 新冠肺炎封锁对西非城市伊巴丹交通相关空气污染物浓度水平的影响

Nigerian Journal of Technological Development Pub Date : 2022-09-23 DOI: 10.4314/njtd.v19i3.3

E. Odedi̇ran, O. Yusuf, A. Adeniran

{"title":"Impacts of Covid-19 Lockdown on Concentration Levels of Traffic-Related Air Pollutants in Ibadan -a West African City","authors":"E. Odedi̇ran, O. Yusuf, A. Adeniran","doi":"10.4314/njtd.v19i3.3","DOIUrl":"https://doi.org/10.4314/njtd.v19i3.3","url":null,"abstract":"Trends and sources of air pollution at twenty-five traffic Intersections (TIs) before and during covid-19 lockdown were investigated in Ibadan, Nigeria. The relationships among climatic parameters, vehicular counts and ten air pollutants which includes particulate matter (PM1, PM2.5, PM10 & Total Suspended Particles-TSP) and gaseous pollutants (CO, NO2, SO2, NH3, total volatile organic compounds-TVOCs, and ground level O3) measured simultaneously at TIs were analysed. Results indicated significant decrease in mean concentrations of all pollutants studied except NO2 with 212% increase during the study period. Concentrations of gaseous pollutants CO, SO2, NH3, TVOCs and ground level O3 reduced by 7.92%, 24.80%, 1.58%, 44.08% and 4.28%, respectively while particulates concentrations of PM1, PM2.5, PM10 and TSP concentrations decreased by 49.64%, 60.79%, 81.21% and 84.17%, respectively during lockdown. An integrated source apportionment approach using Pearson’s correlation, Airflow backward trajectories arriving in the study area and Principal component analysis (PCA) identified vehicular emission as the primary source of studied air pollutants at TIs before and during lockdown in Ibadan. Emission from residences, roadside fuel combustion and local air transport of pollutants from nearby upwind areas with industries and farming activities were identified as secondary sources of air pollution affecting the study area.","PeriodicalId":31273,"journal":{"name":"Nigerian Journal of Technological Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45678079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

High impedance fault arc analysis on 11 kV distribution networks 11kV配电网高阻抗故障电弧分析

Nigerian Journal of Technological Development Pub Date : 2022-08-01 DOI: 10.4314/njtd.v19i2.6

P. Obi, E. Amako, C. S. Ezeonye

{"title":"High impedance fault arc analysis on 11 kV distribution networks","authors":"P. Obi, E. Amako, C. S. Ezeonye","doi":"10.4314/njtd.v19i2.6","DOIUrl":"https://doi.org/10.4314/njtd.v19i2.6","url":null,"abstract":"This paper presents a study of high impedance fault (HIF) arc analysis on 6 km 11 kV distribution network from New Haven to New NNPC, Enugu State. These HIF currents have low fault current ratings and are not readily detected by the distribution sub-station relays and protective equipment. This was realized with the aid of MATLAB. Firstly, the HIF was modelled based on the electric arc theory method for single line-to-ground and double line-to-ground faults, when the 11 kV New-haven to New NNPC Enugu distribution line interfaces with a dry asphalt ground surface. The HIF was incident on the midpoint of the distribution line between the switching times of the circuit breaker from 0.02 to 0.05 seconds. The results showed that for single line-to-ground and double line-to-ground faults, a peak current magnitude of 12.4 A and 2280 A were seen respectively and initial spikes due to arcing in the system voltages at the initial switching times of 0.02 seconds. The corresponding residual currents Ib and Ic are very small with a peak spike of 0.3 A and 1.9 A for double line-to-ground fault (BC-G). These spikes are because of the impact of the initial transients caused by the arc flames as its quenches and re-ignites.","PeriodicalId":31273,"journal":{"name":"Nigerian Journal of Technological Development","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43704145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1