148 research outputs found
Review of Soil Erosion Assessment using RUSLE Model and GIS
Soil erosion is one of the world environmental problems the world is facing in the 21st century affecting human society and is listed amongst the top environmental issues facing the world including increasing human population, water shortages, loss of biodiversity, energy and human diseases. An estimated 10 million hectares of agricultural lands are degraded and turned into un-farmable areas due to soil erosion thus resulting in reduced food production for the 3.7 billion malnourished people as reported by World Health Organization. Estimation of soil erosion loss and evaluation of soil erosion risk has become an urgent task by many nations before implementing soil conservation practices. There is now a large published literature on the application of the Revised Universal Soil Loss Equation known as the RUSLE model in combination with GIS technology for predicting soil loss and erosion risks in different regions. This review paper assesses the current literature on the combined application of RUSLE and GIS, examining new developments in deriving the five RUSLE components. The literature review shows that using the traditional RUSLE model in mapping out soil erosion in large watersheds poses challenges. The combined effect of RUSLE and GIS provides a useful and efficient tool for predicting long-term soil erosion potential and assessing soil erosion impacts. However, there is a need to further investigate better ways of deriving the conservation and management factor (P) in the RUSLE for better on future studies. Data source and quality is also another key issue in GIS application, thus great care must be given in checking and pre-processing GIS data, including conversion to different formats, geo-referencing, data interpolation and registration. Finally, validation of the soil erosion loss using reference data is also a valuable input towards improving the quality and correctness of the results. Keywords: Soil erosion, RUSLE, watershed, GI
Speciation of heavy metals in the sidments of Gubi dam, Bauchi state, Nigeria
Speciation of heavy metals in the sediments of Gubi Dam in Bauchi, Nigeria was carried out between December, 2001 and March, 2002. The mean total concentrations showed that Tatimari tributary has high Fe, Zn, and Mn, confirming it source and path. The spillway result suggest intensive farming activity along the dam runway. However, the physio-chemical forms of Fe, Pb, and Cr indicate that these metals are associated in high concentration with the mineral matrix of the sediment, as such it is most unlikely to become biologically available. High levels of Cu, Cd, Zn, Mn, Co and Ni are associated with the exchangeable carbonate bound fractions, indicating that they are in potentially available forms and many pose serious problems to the dam ecosystem.KEY WORDS: Sediments, Speciation, Heavy metals, Gubi Dam, Nigeri
Levels of heavy metals in Gubi dam water Bauchi, Nigeria
The distribution of heavy metals in Gubi Dam, Bauchi, Nigeria was studied covering the highest turbulent and non-turbulent flow periods. The average concentrations of iron, manganese, nickel, zinc, cobalt, chromium and cadmium were generally highest in filtrate water, whereas the concentrations of copper and lead were always highest in the suspended materials which indicate the dominant role played by suspended materials in the transport of these metals. The total metal levels are within WHO safety limits as such do not reflect impaired suitability of the water. The relative levels of the metals at the entry points and spillway reflect the source, the path and stopover of the tributaries of the dam, thus the variation in the amount of metals at each point.KEYWORDS: Distribution, Heavy metals, filtrate water, suspended matter, Gubi dam, Nigeri
Industrial revolution (IR) 4.0 in construction engineering education: a bibliometric analysis
Industrial Revolution 4.0 (IR 4.0) is a high technology digitization to enhance communication networks,
organization and management, as well as production and processes across industries. The rate of
changes and its convergence towards IR 4.0 would require new talent, knowledge and skills for current
and future generations to retain and generate new workforces. As technology in the construction
industry is evolving at a fast pace, the current teaching-learning syllabus and pedagogy should
transform accordingly to accommodate future job requirements. Due to the rawness of this concept in
the construction industry and to its education, this study aims to explore the state of the art as well as
the state of practice of IR 4.0 and Education 4.0 from the perspective of construction engineering.
Therefore, a systematic review was conducted to analyze the relevant research papers related to IR
4.0 and Education 4.0 within the Scopus database, ranging from year 2011 until present. A bibliometric
analysis has been outlined following the Preferred Reporting Items for Systematic Review and Meta-
Analyses (PRISMA) statement. Findings from this study would provide a thorough understanding on
the past efforts in advancing the construction engineering education aspect, subsequently highlighting
gaps to be filled for future endeavors, particularly in equipping the construction engineering education
for IR 4.0
Characterization of PVDF-HFP-LiCF3S03-Zr02 nanocomposite polymer electrolyte systems
Nanocomposite polymer electrolytes were prepared by incorporating different amounts of zirconium oxide (Zr02) nanofiller to poly(vinylidene fluoride-co exafluoropropylene)-lithium trifluoromethane sulfonate (PVDF-HFP-LiCF3S03). X-ray diffraction (XRD) study has been carried out to investigate the structural features of the electrolyte films while a.c. impedance spectroscopy has been performed to investigate their electrical properties. The conductivity of nanocomposite polymer electrolyte systems is influenced by nanofiller concentration. The increase in conductivity is attributable to the increase in the fraction of amorphous region and the number of charge carriers and vice versa. The highest conductivity obtained is in the order of 10-3 S cm-1 for the system dispersed with 5 wt% of Zr02 nanofiller
The Usability of C++ Interactive Self-Assessment Quiz (i-SAQ)
The rising of technologies these days affected most of the sectors in the country including education. Traditional assessment method gives difficulty to both students and lecturers in term of learning and teaching process. Therefore, this study proposed an online quizzes application called i-SAQ (C++ Interactive Self-Assessment Quiz) which adopt formative assessment method to help students and lecturers in their learning and teaching process. The feature of i-SAQ which offers immediate feedback while answering the quiz attracts students in having a hassle-free way of discovering knowledge. This feature also helps lecturers in handling large number of students in term of giving the feedback from formative assessment. The usability test was conducted to a group of 64 students to test the functionality of i-SAQ by using questionnaire approach. From the analysis, most of the students gave highest points for every questionnaire usability factors which shows that i-SAQ is one useful and interesting learning support tool
Effect of Water to Cement Ratio and Replacement Percentage of Recycled Concrete Aggregate on the Concrete Strength
Fine Recycled Concrete Aggregate (FRCA) is one of the construction waste can be recycled. It can be the aggregate to replace the natural aggregate in concrete since we know the physical properties of materials are hard and strong. Demand for sand in the concrete production has been increased which become the problems in the concrete industry. This work deals with the effect of concrete incorporating with FRCA as partial replacement of sand. The percentage of natural sand replaced by the FRCA was 0%, 15%, 20%, 25%, 30%, 45% and 60%. Other than that, water cement ratio was manipulated variable started form 0.40, 0.45, 0.50, 0.55 and 0.60. In short, 20% replacement was the most suitable interaction of FRCA in the concrete occur that contribute to increasing in compressive strength. The porosity properties of FRCA been neutralized on that replacement percentage by the present of optimum filler effect generated form the very fine FRCA particle during the mixing process. Meanwhile, 0.50 water cement ratio was optimum condition for cement hydration process using FRCA as partial sand replacement
ActivityNET: Neural networks to predict public transport trip purposes from individual smart card data and POIs
Predicting trip purpose from comprehensive and continuous smart card data is beneficial for transport and city planners in investigating travel behaviors and urban mobility. Here, we propose a framework, ActivityNET, using Machine Learning (ML) algorithms to predict passengers’ trip purpose from Smart Card (SC) data and Points-of-Interest (POIs) data. The feasibility of the framework is demonstrated in two phases. Phase I focuses on extracting activities from individuals’ daily travel patterns from smart card data and combining them with POIs using the proposed “activity-POIs consolidation algorithm”. Phase II feeds the extracted features into an Artificial Neural Network (ANN) with multiple scenarios and predicts trip purpose under primary activities (home and work) and secondary activities (entertainment, eating, shopping, child drop-offs/pick-ups and part-time work) with high accuracy. As a case study, the proposed ActivityNET framework is applied in Greater London and illustrates a robust competence to predict trip purpose. The promising outcomes demonstrate that the cost-effective framework offers high predictive accuracy and valuable insights into transport planning
Climate Change Awareness and related Tree Planting Practices in a Rural Community in North-Western Nigeria
Background: Tree cutting is one of the causes of climate change and a common practice in Africa, a continent under significant threat from climate change. Therefore, climate change awareness and mitigation are vital to reducing its impacts in the region. Reforestation through planting of trees is an important carbon emission reduction strategy. This study assessed climate change awareness and related tree planting practices among household heads in a Nigerian rural community.Methods: A community-based descriptive, cross-sectional study was conducted in April 2019 among all household heads in Nasarawan Buhari community. An interviewer-administered questionnaire was used to collect data from the 104 household heads (or their representatives). Data was analyzed using SPSS (version 21.0) and statistical significance was set at p value of < 0.05.Results: The mean age of respondents was 40.6±12.6 years, and most of them (87.5%) were males. Half (50.0%) were aware of climate change, and their main source of information was radio (63.5%). Most (98.1%) used fire wood for cooking. Only a minority (27.9%) planted at least a tree in the year preceding the study. There was a statistically significant association between climate change awareness and occupation (p=0.038) but not with tree planting (p=0.827).Conclusion: The results indicated that only half of respondents were aware of climate change. There was high use of wood as cooking fuel with low tree planting. Tree planting was not associated with climate change awareness. There is therefore a need for continuous climate change education and mitigation campaign in the community
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