UNIOSUN Journal of Engineering and Environmental Sciences最新文献_第7页

Comparative Analysis of Rain–Induced Attenuation Models Over Some Selected Nigerian Cities 尼日利亚部分城市雨致衰减模式的比较分析

UNIOSUN Journal of Engineering and Environmental Sciences Pub Date : 2022-03-31 DOI: 10.36108/ujees/2202.40.0122

C. J. Iroka

{"title":"Comparative Analysis of Rain–Induced Attenuation Models Over Some Selected Nigerian Cities","authors":"C. J. Iroka","doi":"10.36108/ujees/2202.40.0122","DOIUrl":"https://doi.org/10.36108/ujees/2202.40.0122","url":null,"abstract":"The fair investigation carried out on rain-induced attenuation at 12.245-GHz over three selected Nigerian cities was carried out in this study. For this work, a time series of rain-induce attenuation at the 12.45 GHz based on 1-minute-rain rate measurements was obtained for -LAUTECH-Ogbomosho, ESUT-Enugu, and FUGUS-Zamfara, respectively in the South West, South East and North Eastern Nigeria over a three-year period (2017–2020). The Received Signal Level (RSL) and rain intensity measurements were sampled at intervals of 10 seconds and integrated over a period of 1 minute. A performance analysis established on the collective allocation of rain rate along with the collective allocation of rain-induced attenuation gotten was reported and compared with some existing rain attenuation models (Garcia Lopez, SAM, Moupfouma and ITU-R models). Attenuation caused by rain as predicted based on the ITU-R and SAM resulted in a clear variation from the measured values by 14%, while the Moupfouma model provides a better fit to the actual attenuation data and then followed by the Garcia Lopez model. The results of this study may be used for planning similar links at the choice frequency band over the locations of interest.","PeriodicalId":23413,"journal":{"name":"UNIOSUN Journal of Engineering and Environmental Sciences","volume":"69 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81466011","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

Performance Evaluation of Construction Projects Delivery in Insurgency Affected Locations in Maiduguri, North East, Nigeria 尼日利亚东北部迈杜古里受叛乱影响地区建筑项目交付绩效评估

UNIOSUN Journal of Engineering and Environmental Sciences Pub Date : 2022-03-31 DOI: 10.36108/ujees/2202.40.0101

A. Ahmad

{"title":"Performance Evaluation of Construction Projects Delivery in Insurgency Affected Locations in Maiduguri, North East, Nigeria","authors":"A. Ahmad","doi":"10.36108/ujees/2202.40.0101","DOIUrl":"https://doi.org/10.36108/ujees/2202.40.0101","url":null,"abstract":"The study carried out a performance evaluation of insurgency risk factors in Borno. The insurgency risk factors were analysed in terms of three keys that enhance the success of project delivery i.e. Cost, Time and Quality. The data for the study were collected through a questionnaire survey and administered to the professionals involved in the construction projects i.e. the Civil Engineers, Architects, Quantity Surveyors, Builders and Project Managers on construction projects in Maiduguri. The obtained information from the above-mentioned professionals relating to their years of experience and the number of projects they have handled during the insurgency period. A sample size of two hundred and twenty (220) from the total list of the aforementioned respondents Civil Engineers, (52), Builders, (40), Architects, (49), Quantity Surveyors, (43), and Project Managers, (36) i.e. two hundred and forty-eight (248). The sample size was collected using the purposive sampling technique as the targeted sample. The data were analysed using the Relative Importance Index (RII) in order to achieve a concrete and accurate analysis. The results were evaluated and ranked based on the high potential risks prevalent within the construction projects executed during the insurgency period.","PeriodicalId":23413,"journal":{"name":"UNIOSUN Journal of Engineering and Environmental Sciences","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88142708","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

Design and Performance Evaluation of a Stone Crusher 石料破碎机的设计与性能评价

UNIOSUN Journal of Engineering and Environmental Sciences Pub Date : 2021-10-07 DOI: 10.36108/ujees/1202.30.0290

I. Sulaiman

{"title":"Design and Performance Evaluation of a Stone Crusher","authors":"I. Sulaiman","doi":"10.36108/ujees/1202.30.0290","DOIUrl":"https://doi.org/10.36108/ujees/1202.30.0290","url":null,"abstract":"Crushers are essential machines in several industries for particle size reduction. They are invaluable in laboratories (higher institutions and research centres), the mining and construction industries. Available crushers are imported and very expensive. This has pushed some workers around Nigeria to crush stones with crude materials and manual labour, to meet the demand of the various sectors while neglecting the hazards involved. A hammer mill has been designed with due considerations to standard design requirements, local content and cost. The power required to crush granite with the desired through put of 400 kg/h was found to be 5.5 kW. Major factors considered for the material selection are the mechanical properties, wear of materials, fabrication requirement and cost. The machine was fabricated using locally available materials. The fabricated stone crusher was tested and the actual capacity was found to be 301 kg/h with a through-put efficiency of 75.4 %. The crushed products were well graded with 1.89 coefficient of gradation and uniformity coefficient of 10.22. The machine was produced at a cost of two hundred and forty-five thousand, two hundred naira (₦245,200.00 {US$595.15}).","PeriodicalId":23413,"journal":{"name":"UNIOSUN Journal of Engineering and Environmental Sciences","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88979270","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

Development and Performance Evaluation of a Hand-Pushed Tiger Nut Harvester 手推式虎果收割机的研制与性能评价

UNIOSUN Journal of Engineering and Environmental Sciences Pub Date : 2021-10-07 DOI: 10.36108/ujees/1202.30.0270

A. Saleh

{"title":"Development and Performance Evaluation of a Hand-Pushed Tiger Nut Harvester","authors":"A. Saleh","doi":"10.36108/ujees/1202.30.0270","DOIUrl":"https://doi.org/10.36108/ujees/1202.30.0270","url":null,"abstract":"Harvesting is one of the major problems encountered by tiger nut farmers in Nigeria. Manual harvesting system is the most commonly used method. This process is costly, labour intensive and time-consuming. The process does not also give farmers adequate returns to enable them to break even due to huge losses encountered. The objective of this study was to design, construct and evaluate a hand-pushed harvester that would eliminate the challenges being faced by small and medium tiger nut farmers during harvesting. Materials selection for constructing the harvester were based on their durability and availability, affordability and ease of replacement if damaged. They include mild steel (3 mm, 5 mm), 30 mm galvanized steel hollow pipe, 10 mm diameter steel rod, and 400 mm steel tyre. The developed harvester was evaluated at the experimental farm of the Institute for Agricultural Research (IAR). Results of the study show that the average field capacity ranges from 0.28 – 0.33 ha/h while the average field efficiency was between 77.78 – 80.49% depending on operating speed, moisture content and other properties of the soil. No field damage was recorded when the harvester was used as against an approximate 10.50% damage recorded in the manual harvesting method.","PeriodicalId":23413,"journal":{"name":"UNIOSUN Journal of Engineering and Environmental Sciences","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81756736","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

Effect of Different Concentrations of Titanium Oxide (TiO2) Addition on the Crystallization Behaviour and Some Properties of Alkaline Earth Aluminosilicate Glass-Ceramics 不同浓度的氧化钛(TiO2)对碱土铝硅酸盐微晶玻璃结晶行为及某些性能的影响

UNIOSUN Journal of Engineering and Environmental Sciences Pub Date : 2021-10-07 DOI: 10.36108/ujees/1202.30.0210

Z. Aliyu

{"title":"Effect of Different Concentrations of Titanium Oxide (TiO2) Addition on the Crystallization Behaviour and Some Properties of Alkaline Earth Aluminosilicate Glass-Ceramics","authors":"Z. Aliyu","doi":"10.36108/ujees/1202.30.0210","DOIUrl":"https://doi.org/10.36108/ujees/1202.30.0210","url":null,"abstract":"Glass-ceramics in the CaO-MgO-Al2O3-SiO2 quaternary base glass system was produced via melting technique using feldspar, limestone and magnesite as sources of starting materials. Glass-ceramics production involves making a base glass, annealing and cooling to room temperature and then reheating the base glass to nucleation and crystal growth temperatures. Characterization of the produced glass-ceramics was carried out using a scanning electron microscope (SEM). The effects of the crystallization process on some properties such as hardness, chemical durability in acid and alkali media of samples were determined. The results portrayed that glass-ceramic samples to which various amounts of TiO2 (2,4,6,8 and 10 wt.%) were incorporated showed the formation of crystalline phases dispersed in the matrix of their respective residual glassy phases. Significant improvement in hardness, as well as minimum weight loss, were recorded for all the glass-ceramic samples. On the contrary, the glass samples did not crystallize despite subjecting them to heat treatment, their hardness values were low and they were not resistant to acid (1M HCl) and alkali (1M NaOH) attacks. The inability of TiO2 addition to fully transform them into glass-ceramics remains a shortcoming. However, the glass-ceramic samples obtained from this study can be used for tiling works.","PeriodicalId":23413,"journal":{"name":"UNIOSUN Journal of Engineering and Environmental Sciences","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85427000","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 Real Estate Outsourcing Practice of Banks and Telecommunication Companies in Lagos, Nigeria 尼日利亚拉各斯银行和电信公司房地产外包实践评估

UNIOSUN Journal of Engineering and Environmental Sciences Pub Date : 2021-01-01 DOI: 10.36108/ujees/1202.30.0240

I. Fayomi

{"title":"Assessment of Real Estate Outsourcing Practice of Banks and Telecommunication Companies in Lagos, Nigeria","authors":"I. Fayomi","doi":"10.36108/ujees/1202.30.0240","DOIUrl":"https://doi.org/10.36108/ujees/1202.30.0240","url":null,"abstract":"The purpose of this paper is to examine real estate services that are outsourced in the banking and telecommunication sectors and the procedures adopted in outsourcing in Nigeria with a view to providing information that could help in enhancing corporate real estate practice. Primary data were collected with the aid of questionnaires from the 27 banks and 6 telecommunication operators (totalling 33) who were assessed through their corporate real estate officers. Total enumeration of the 33 selected business organisations was purposively adopted and the data were analysed using frequency and percentage. The study found that 96.3% and 83.3% of banks and Telecommunication companies respectively insourced real estate strategic planning services A total of (69.7%) in-sourced client relationship management. Also, the most frequently outsourced services by banking and telecommunication companies were property valuation (72.7%), space planning (54.5%), facility management (54.5%), feasibility studies (33.3%), site selection and property leases (55.5%) among others. The result also showed that two (6.05%) categories of organizations adopted the World Bank procedures for selecting outsourced real estate consultants. Professional Estate Surveyors must be up and doing when services are outsourced to them so as prevent usurpation of responsibility and functions from professionals in the built environment and others competing for works in the estate surveying valuation business domain","PeriodicalId":23413,"journal":{"name":"UNIOSUN Journal of Engineering and Environmental Sciences","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75102675","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

Upgrading the Glass Bead Making Furnace for Ease of Operation: A Case Study of the Masaga Glass Guild 为便于操作而升级玻璃珠制造炉:以马萨加玻璃协会为例

UNIOSUN Journal of Engineering and Environmental Sciences Pub Date : 2021-01-01 DOI: 10.36108/ujees/1202.30.0230

E. M. Alemaka

{"title":"Upgrading the Glass Bead Making Furnace for Ease of Operation: A Case Study of the Masaga Glass Guild","authors":"E. M. Alemaka","doi":"10.36108/ujees/1202.30.0230","DOIUrl":"https://doi.org/10.36108/ujees/1202.30.0230","url":null,"abstract":"The glass bead making furnace of the Masaga Glass Guild in Bida, Niger State Nigeria was evaluated in comparison to those of Ghana (Krobo) and India (Firozabad); it was discovered that the Masaga furnace falls short of an efficient system for sustainable work that should facilitate appreciable productivity. Furthermore, the furnace is not built with refractory bricks, implying that it has a short life span; the furnace is operated by hand-worked traditional cloth bellows requiring sustained and strenuous efforts over a relatively long period of time; Following this assessment, efforts were directed at modifying the furnace by producing design drawings of the modified furnace, design and production of refractory bricks from the design drawing, constructing the modified furnace structure using the refractory bricks, producing suitable furniture for the furnace and subsequently, devising a suitable mechanical blower device as an alternative to the manually worked bellows for the supply of combustion air. Consequently, a furnace was developed which eliminates the strenuous manual working of the bellows as well as the bellow operator and ensures that a single individual can work unassisted at the furnace in the process of glassware production.","PeriodicalId":23413,"journal":{"name":"UNIOSUN Journal of Engineering and Environmental Sciences","volume":"150 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80138568","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

Students’ Satisfaction with Teaching Spaces: Study of a State-Owned University in Southwestern Nigeria 学生对教学空间的满意度:对尼日利亚西南部一所公立大学的调查

UNIOSUN Journal of Engineering and Environmental Sciences Pub Date : 2021-01-01 DOI: 10.36108/ujees/1202.30.0280

O. A. Ayodeji

{"title":"Students’ Satisfaction with Teaching Spaces: Study of a State-Owned University in Southwestern Nigeria","authors":"O. A. Ayodeji","doi":"10.36108/ujees/1202.30.0280","DOIUrl":"https://doi.org/10.36108/ujees/1202.30.0280","url":null,"abstract":"Teaching spaces are needed for direct or physical contact between lecturers and students. The degree of students’ satisfaction with teaching facilities and services provided in our universities are likely to influence their academic performance. This study examined the factors influencing students’ satisfaction with learning spaces in Osun State University, Osun State, Nigeria. A sample size of 591 respondents drawn from 300 level and 400 level in the College of Science, Engineering and Technology (Osogbo Campus) and the College of Management and Social Science (Okuku Campus) were sampled through a structured questionnaire on a 5-point Likert scale using a random cluster sampling technique. The results revealed that students were very satisfied with the spatial and physical configurations of the teaching spaces. Attitude to learning and students’ subject understanding were highly and positively related to students’ satisfaction, their respective values were 0.751 and 0.721. The paper concluded with suggestions on how students’ satisfaction can be improved by providing facilities that will enable electronic teaching and learning.","PeriodicalId":23413,"journal":{"name":"UNIOSUN Journal of Engineering and Environmental Sciences","volume":"106 5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89737328","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

Acceptability of Corbel Construction for Housing Development in Ogbomoso, Southwest, Nigeria 尼日利亚西南部Ogbomoso的房屋开发的可接受性

UNIOSUN Journal of Engineering and Environmental Sciences Pub Date : 2021-01-01 DOI: 10.36108/ujees/1202.30.0260

O. Odunjo

{"title":"Acceptability of Corbel Construction for Housing Development in Ogbomoso, Southwest, Nigeria","authors":"O. Odunjo","doi":"10.36108/ujees/1202.30.0260","DOIUrl":"https://doi.org/10.36108/ujees/1202.30.0260","url":null,"abstract":"This study assesses the knowledge and attitude of people on the use of corbel arch for lintel construction to reduce concreting in housing construction. Ogbomoso was the case study and Ikose community was purposively selected being a fringe area receiving an influx of people from the city. Google earth and ground-truthing were used in capturing one hundred and eighty-nine inhabited houses and questionnaire was the instrument for data collection and was administered to collect information on the socio-economic background of respondents, knowledge of material and willingness to utilise. Descriptive statistics were employed in the presentation of findings; chi-square was used to test the relationship between characteristics of residents and willingness to adopt the material. Analysis showed that 32.5% were 51-60 years; 60.4% were male; while 62.1% of the respondents were married. Also, 38.2% had modern/ secondary/technical/teacher’s grade II certificate, while 38.1% were traders. Only 12.1% of respondents knew the material, 68.5% were willing to utilise based on availability within the environment and ability to mitigate the effect of climate change, while 57.1% will recommend its usage. Gender, educational background, income and access to information are significantly related to willingness to utilise the material (P =0.000). Suggestions were made towards factoring the material into housing policies in Nigeria.","PeriodicalId":23413,"journal":{"name":"UNIOSUN Journal of Engineering and Environmental Sciences","volume":"331 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79725537","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

Valuers’ Perception of Expert Witnessing in Real Estate Litigation Practice in Ibadan, Oyo State 奥约州伊巴丹房地产诉讼实践中估价师对专家见证的感知

UNIOSUN Journal of Engineering and Environmental Sciences Pub Date : 2021-01-01 DOI: 10.36108/ujees/1202.30.0220

A. Adedokun

{"title":"Valuers’ Perception of Expert Witnessing in Real Estate Litigation Practice in Ibadan, Oyo State","authors":"A. Adedokun","doi":"10.36108/ujees/1202.30.0220","DOIUrl":"https://doi.org/10.36108/ujees/1202.30.0220","url":null,"abstract":"The study examined the valuers’ perception of expert witnessing in real estate litigation in Ibadan, Oyo State with the aim of improving professional practice. Primary data was collected from respondents 103 registered valuers (RSV) drawn using systematic random sampling technique from 158 financial members contained in the Estate Surveyors and Valuers Registration Board of Nigeria (ESVARBON) directory. Data collected from 87 returned questionnaires were analysed using frequency, percentage distribution, mean scores and factor analysis. The result established that rent dispute was the commonest real estate litigation where Valuers as an expert witness had been involved. The result shows that expert witnesses in the study area were experienced professional valuers who could sufficiently guide decision making in real estate litigations and give objective and sound evidence. Also, the findings showed that there is no statistically significant variation between the professional qualification and their level of engagement in real estate litigation as the p>.05 level for respondents [F(2,76)=.067, p= .935] for ESV. This infers that the respondents’ involvement in litigation was not a function of professional qualification of the respondents. The study recommended that for efficient expert witnessing in real estate litigations, valuers need to understand the procedures of being an expert witness and develop sufficient knowledge in the area of expert witnessing.","PeriodicalId":23413,"journal":{"name":"UNIOSUN Journal of Engineering and Environmental Sciences","volume":"79 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72638553","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