Nigerian Journal of Technology最新文献

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A linear model-based simulation tool for estimating number of trials needed for upper limb stroke recovery in a given rehabilitation session 一个基于线性模型的仿真工具,用于估计在给定的康复过程中上肢卒中恢复所需的试验数量
Nigerian Journal of Technology Pub Date : 2023-11-03 DOI: 10.4314/njt.v42i3.10
B.E. Faremi, K.P. Ayodele, A.M. Jubril, A.A. Fakunle, M.O.B. Olaogun, M.B. Fawale, M.A. Komolafe
{"title":"A linear model-based simulation tool for estimating number of trials needed for upper limb stroke recovery in a given rehabilitation session","authors":"B.E. Faremi, K.P. Ayodele, A.M. Jubril, A.A. Fakunle, M.O.B. Olaogun, M.B. Fawale, M.A. Komolafe","doi":"10.4314/njt.v42i3.10","DOIUrl":"https://doi.org/10.4314/njt.v42i3.10","url":null,"abstract":"Traditional methods for assessing upper-limb functional outcomes in stroke patients often fail to estimate the number of trials required to achieve performance stability of a chosen kinematic metric. Limited non-model-based studies have attempted to tackle this issue. To bridge this gap, this study utilized an iterative learning algorithm (ILA) in MATLAB, employing linear models to represent the muscle dynamics and forearm extension of impaired patients. The reference task space trajectory was set as a straight-line point-point trajectory within a range of 0 - 0.2828m. By using the root mean square error (RMSE) as a metric for evaluating kinematic accuracy, a maximum kinematic deviation error of 0.01m was imposed with respect to the trajectory by the (ILA). Results indicate that over 16 trials, performance stability was obtained with improvement in deviation error from 0.0168m in the first trial to 0.0060 at sixteen trials. The result obtained is in line with similar non-model studies and our findings inform the potential of ILAs with linear models for estimation of trial numbers required to attain performance stability of a selected kinematic metric (i.e., kinematic accuracy).","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":"24 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135875282","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
Load profiling of commercial and residential building using clustering technique 基于聚类技术的商住建筑负荷分析
Nigerian Journal of Technology Pub Date : 2023-08-11 DOI: 10.4314/njt.v42i2.14
A. Olawumi, F. Dahunsi
{"title":"Load profiling of commercial and residential building using clustering technique","authors":"A. Olawumi, F. Dahunsi","doi":"10.4314/njt.v42i2.14","DOIUrl":"https://doi.org/10.4314/njt.v42i2.14","url":null,"abstract":"Data mining is a promising tool used in processing energy data collected from energy consumers. The knowledge derived from energy data is very pertinent in the formulation of various demand-side management programs. This paper uses clustering techniques to segment the energy consumption patterns of residential and commercial buildings; situated at different geographical locations. The two (2) commonly used clustering techniques: K-Means and Agglomerative Hierarchical Clustering, were employed. The result indicates that the choice of clustering technique for load profiling is highly subjective to the nature of the dataset. Hence, using Davies-Bouldin Index (DB) Index and Silhouette Index (SI) as clustering indicators to select an optimum number of clusters and the best clustering technique. Hierarchical clustering was identified as the most appropriate clustering for the two buildings.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42344974","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
Mix design optimization of high-performance concrete using local materials 就地取材的高性能混凝土配合比设计优化
Nigerian Journal of Technology Pub Date : 2023-08-11 DOI: 10.4314/njt.v42i2.2
E. Ikponmwosa, K. Olonade, A. Sulaiman, E. O. Akintunde, N. O. Enikanologbon, O. Kehinde
{"title":"Mix design optimization of high-performance concrete using local materials","authors":"E. Ikponmwosa, K. Olonade, A. Sulaiman, E. O. Akintunde, N. O. Enikanologbon, O. Kehinde","doi":"10.4314/njt.v42i2.2","DOIUrl":"https://doi.org/10.4314/njt.v42i2.2","url":null,"abstract":"In this paper, twelve different concrete mixes made from local materials were studied with a view to determining which of the mix designs will produce high-performance concrete. Varied water-cement ratios (w/c) of 0.3, 0.35, and 0.4 were studied with different combinations of particle sizes of coarse aggregates. Twelve concrete mixes were then produced, cast, and cured for 7, 14, 21, 28, 45, and 90 days. Superplasticizer was used to facilitate the workability of the concrete mixes. A slump test was first conducted on the fresh concrete to determine its workability, while compressive, flexural, and tensile strength were determined at the end of each curing age in accordance with relevant standards. The results shows that slump value increased with an increase in w/c ratio, while the concrete with 100% 10 mm particle size coarse aggregate had a minimum slump of 24, 37, and 50 mm at w/c of 0.3, 0.35 and 0.4 respectively, but higher slump values of 70, 76 and 83 mm were obtained with concrete containing larger particle sizes combination i.e. 25% of each of 10, 12, 15 and 19 mm sizes. But strengths reduced with an increase in w/c and aggregate particle sizes. Concrete produced with w/c of 0.3 and 10 mm coarse aggregates had a strength of 52.22N/mm2 at 28 days, which was about 126% of other strengths obtained from other mixes. Statistical models were then proposed to predict the strength of the best-performed concrete mix. The study concluded that it was possible to produce high-performance concrete using local materials, if the mix is properly optimized.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42995194","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
Optimal design analysis of substation ground grid mesh 变电站地网网优化设计分析
Nigerian Journal of Technology Pub Date : 2023-08-11 DOI: 10.4314/njt.v42i2.16
A. Akhikpemelo
{"title":"Optimal design analysis of substation ground grid mesh","authors":"A. Akhikpemelo","doi":"10.4314/njt.v42i2.16","DOIUrl":"https://doi.org/10.4314/njt.v42i2.16","url":null,"abstract":"Substations are grounded by means of earth-embedded electrodes in order to provide safety during normal or fault conditions. Electric substations are effectively grounded to guarantee the proper operation of electrical devices, minimize the likelihood of flash-over during transient conditions as well as dispel lightning strokes. A structure is termed grounded if it is electrically bonded to earth-embedded metallic frames. The earth-embedded metallic frames provide a conducting pathway of electricity to the earth and it is called a ground grid system. Substation ground grid mesh is comprised of vertical and horizontal conductors as well as vertical rods buried beneath the substation ground. Electric current flow through the human body is hazardous. Therefore, ground grid systems should be designed such that the likely electric body current in an operator or passer-by should not exceed the standard defined limits under any foreseeable harmful circumstances and as well provide protection of equipment. The objective of this study is to determine substation, safe ground grid system parameters as well as the cost-effectiveness of designing substation ground grids by comparing the IEEE Std. 80-2000/2013 and the Finite Element Method (FEM). ETAP 16.0 Power Tool is employed in carrying out this analysis. The substation expected maximum short circuit current is stated. The design analysis using both methods is presented separately and suggestions are made with reference to the most cost effective and safest method for the effective designing of the substation ground grid system.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47108272","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
Influence of compactive effort on the strength characteristics of lime treated laterite soil mixed with untreated textile effluent 压实力对石灰处理红土土与未处理纺织废水混合强度特性的影响
Nigerian Journal of Technology Pub Date : 2023-08-11 DOI: 10.4314/njt.v42i2.6
F. Bayang, J. Sani, O. K. Kevin, T. S. Ijimdiya
{"title":"Influence of compactive effort on the strength characteristics of lime treated laterite soil mixed with untreated textile effluent","authors":"F. Bayang, J. Sani, O. K. Kevin, T. S. Ijimdiya","doi":"10.4314/njt.v42i2.6","DOIUrl":"https://doi.org/10.4314/njt.v42i2.6","url":null,"abstract":"Industrial waste generated is a major contributor of total waste worldwide. The proper mechanism for management of these waste needs to be established, especially in developing countries. Therefore, this paper attempts to evaluate the influence of compactive effort on the strength characteristics of lime treated laterite soil mixed with untreated textile effluent. The study was carried out on the index properties, unconfined compressive strength (UCS) and California bearing ratio (CBR) in accordance with the procedures specified by BS 1377 (2) 1990, 1924 (2) and Nigeria General Specifications. Three compactive efforts namely; British Standard light (BSL), West African Standard (WAS) and British Standard Heavy (BSH) were used for the strength characteristics. The findings of the study showed that an increase in the values of lime-TE results in general increase in the strength tests. An improvement in the UCS for 7, 14 and 28days curing period was recorded at peak values of 1531.91, 2199.29 and 2560.48kN/m2 for BSL, WAS and BSH at soil-lime-TE of 4% lime/75% TE, 8% lime/75% TE and 8% lime/50% TE respectively. For the CBR (soaked), the peak values were recorded at 49.70, 71.13 and 97.25% for BSL, WAS and BSH at soil-lime-TE of 6% lime/50% TE, 6% lime/50% TE and 8% lime/50% TE respectively. Considering the resistance to loss in strength, the values were also peaked at 71.77, 81.74 and 60.63kN/m2 at mix ratios of 8% lime/100% TE, 6% lime/75% TE and 8% lime/25% TE respectively. On the bases of these test results, it can be concluded that the utilization of untreated Textile Effluent positively increased the strength characteristics of the lime treated soil, reduced environmental pollution and save construction cost.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44031829","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: 2
An approach to cybercrime issues in Dandume Local Government Area of Katsina State, Nigeria 尼日利亚卡齐纳州丹杜姆地方政府区域的网络犯罪问题处理方法
Nigerian Journal of Technology Pub Date : 2023-08-11 DOI: 10.4314/njt.v42i2.13
J. Garba
{"title":"An approach to cybercrime issues in Dandume Local Government Area of Katsina State, Nigeria","authors":"J. Garba","doi":"10.4314/njt.v42i2.13","DOIUrl":"https://doi.org/10.4314/njt.v42i2.13","url":null,"abstract":"This study investigated cybercrime issues in Dandume Local Government Area of Katsina State. The study aimed to understand the various types of cybercrimes that the community faces and the resulting impacts, particularly educational and psychological effects on the victims. Additionally, the study discussed the main causes of these crimes, particularly among young people. To achieve these aims, the study collected data from 115 residents of Dandume using a structured questionnaire. The collected data was analyzed using statistical tables. The results showed that cybercrime is prevalent in the Dandume community, with many of the participants reporting that they had experienced one form of cybercrime or the other. The most common types of cybercrime reported by the participants were yahoo attack, social media hijacking, credit card threat, government offer scam, and airtime scam. Furthermore, the study revealed that many of the participants were not aware of the various ways they could protect themselves from cybercrime. Furthermore, the study highlighted the effects of these crimes on the victims and discussed the main causes of cybercrimes among users of internet in the area. The paper made some recommendations for minimizing the challenges of cybercrime in Nigeria. The study underscored the importance of community education and awareness-raising on the dangers of cybercrime and suggests the need for increased efforts to implement security measures to protect residents from cybercriminals.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44046731","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
Editorial 编辑
Nigerian Journal of Technology Pub Date : 2023-08-11 DOI: 10.4314/njt.v42i2.1
C. Nnaji
{"title":"Editorial","authors":"C. Nnaji","doi":"10.4314/njt.v42i2.1","DOIUrl":"https://doi.org/10.4314/njt.v42i2.1","url":null,"abstract":"No abstract.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46529017","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
Adaptive real-time spectrum selection framework and handover decision algorithm (RSSF-HDA) for heterogeneous networks 异构网络自适应实时频谱选择框架及切换决策算法
Nigerian Journal of Technology Pub Date : 2023-08-11 DOI: 10.4314/njt.v42i2.15
V. O. Nkeleme, L. Oborkhale, G. Sani
{"title":"Adaptive real-time spectrum selection framework and handover decision algorithm (RSSF-HDA) for heterogeneous networks","authors":"V. O. Nkeleme, L. Oborkhale, G. Sani","doi":"10.4314/njt.v42i2.15","DOIUrl":"https://doi.org/10.4314/njt.v42i2.15","url":null,"abstract":"Carrier aggregation (CA) is a technology introduced by the Long-Term Evolution-Advanced (LTE-A) system to increase user throughput by combining a selected number of component carriers (CCs). Its integration with heterogeneous networks enables the mobile user equipment to take advantage of increased throughput and radio coverage of various access technologies. However, due to the mobility of user equipment, these innovations have increased the likelihood of handoff scenarios, resulting in a high outage probability and low throughput. Handover is a crucial part of mobility management since it enables users to move from one cell to another while maintaining connections. However, no single access technique can provide seamless communication without interruption or delay. As a result, creating a suitable handover decision algorithm is necessary for ensuring high-quality service continuity and dependable user equipment access to the network at all times. An Adaptive Real-Time Spectrum Selection Framework and Handover Decision Algorithm (RSSF-HDA) with optimal resource allocation to the deployed system model is presented in this paper. This effort is geared toward preventing communication failure and improving system performance. It further positions the 4G LTE-A framework for inclusive coexistence with the current 5G New Radio enhanced Mobile Broadband (eMBB) use case scenario. The results of the simulation reveal that this method increases system performance in terms of Cell edge spectral efficiency and Handover success rate above 10% and 13%, respectively, when compared to Conventional Handover Decision Algorithm (Conv-HDA) and Multi-Influence Factor Handover Decision Algorithms (MIF-HDA).","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49155702","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
Ddetermination of bond work index of Bagega gold mineral deposit of Zamfara State, Nigeria 尼日利亚扎姆法拉州Bagega金矿床粘结功指数的测定
Nigerian Journal of Technology Pub Date : 2023-08-11 DOI: 10.4314/njt.v42i2.12
E. O. Oji, A. D. Omah, Y. H. Onymisi
{"title":"Ddetermination of bond work index of Bagega gold mineral deposit of Zamfara State, Nigeria","authors":"E. O. Oji, A. D. Omah, Y. H. Onymisi","doi":"10.4314/njt.v42i2.12","DOIUrl":"https://doi.org/10.4314/njt.v42i2.12","url":null,"abstract":"The study determined the bond work index of Begaga gold mineral deposit of Zamfara State Nigeria using Berry and Bruce modified bond method. Sample of gold mineral was sourced using random sampling method. Reference mineral (Granite) of known weight and work index of 15.13Kwh/ton was ground for thirty minutes at a particular speed and power consumed was determined from the power rating of the ball mill. An identical weight of Bagega gold mineral whose work index was to be determined was ground in the same ball mill under same condition as that of reference mineral. Size analysis of the ball mill under same condition as that of the reference mineral was performed. Size analysis of the ball mill feed and discharge for both ores was carried out and 80% passing particle size of the ball mill feed and discharge for the two ores were estimated mathematically using correlation approach. The work index of the Bagega gold mineral was determined by equating the power consumed in the two indexes of the ore. It was found to be approximately 14.24Kwh/ton which is within the acceptable range of 10 - 15.14Kwh/ton indicated in literatures as standard work index range of gold. This value of the work index means that 14.25Kilowatts hour of energy is required to reduced one tonne of the gold ore from 80% passing particle size of 1117.32μm to 80% passing particle size of 800.00μm, it should serve as the work index of Bagega gold.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44482777","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
Assessment of the physico-chemical quality of Uturu section of Aku river in southeastern Nigeria 尼日利亚东南部阿库河Uturu河段理化质量评价
Nigerian Journal of Technology Pub Date : 2023-08-11 DOI: 10.4314/njt.v42i2.19
O. Chinyere, Y. Sanusi, F. Anafi
{"title":"Assessment of the physico-chemical quality of Uturu section of Aku river in southeastern Nigeria","authors":"O. Chinyere, Y. Sanusi, F. Anafi","doi":"10.4314/njt.v42i2.19","DOIUrl":"https://doi.org/10.4314/njt.v42i2.19","url":null,"abstract":"The physicochemical monitoring of water quality is very key both to aquatic life and public health. To date little is known about the water quality downstream of Aku river, located in Uturu, Isuikwato local government area of Abia state. Therefore the aim of the study is to determine the water quality downstream of Aku river in terms of several physicochemical parameters and heavy metals analysis to ascertain the water quality properties and reveal pollution problems. Samples were collected at 15m, 30m, 45m, 60m, 75m, 90m and 105m interval downstream for both seasons. Results of the study shows that temperature, conductivity, hardness, salinity, Total Dissolve Solid (TDS), Total Suspended Solids (TSS), turbidity, pH, Dissolve Oxygen (DO), chlorine, nitrate, lead, iron, arsenic, copper and zinc, were ranged: 24.190C-26.500C, 165.18-275.46μs/cm, 100.26-139.11mg/L, 520.15-815.24ppt, 380.52-710.08mg/L, 15.12-30.68mg/L, 0.32-1.73NTU, 6.6-7.9, 6.21-11.63mg/L, 1.14-3.30mg/L, 65.01-128.05mg/L, 35.53-58.00mg/L, 0.0002-0.007ppm, 0.02-0.15ppm, 0.002-0.006ppm, 0.44-1.03ppm and 0.1-0.27ppm respectively. The presence of TDS, TSS, turbidity and nitrate above World Health Organization (WHO) tolerance limits, confirmed the presence of contaminants in the water body, and hence not suitable for drinking and thus poses a potential threat to aquatic life.","PeriodicalId":33360,"journal":{"name":"Nigerian Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43915940","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
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