LAUTECH Journal of Engineering and Technology (LAUJET)
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MINERALOGICAL STUDIES OF WEATHERED PEGMATITE AROUND KITIBI-IWOYE, SOUTHWESTERN NIGERIA
Get PDFWeathering profile of pegmatite around Kitibi-Iwoye and Awo mining sites is heterogeneously composed of primary and secondary mineral constituents. Weathered materials obtained from nine dug pits and pegmatite samples were studied with a view to gaining insight into the mineral assemblages constituting the weathered materials. This was achieved by describing the field, petrographic and mineralogical features of the pegmatite and its weathered components. Effect of weathering on the pegmatitic parent rock leading to the evolution of secondary minerals was as well investigated. The authors are not aware of any previous investigation existing in these aspects in the study area.
This study involved geological mapping of the study area. Representative samples of pegmatite were collected for microscopic examination. Unconsolidated weathered mass obtained from the Saprolite and B-horizon was air dried. The loosened mass was sieved and screened to remove organic components and detrital quartz. The pulverized samples were analysed using X-Ray Diffractometry (XRD) technique in the Department of Geological Sciences, University of Cape Town, South Africa.
The Northeastern-Southwestern (NE-SW) trending pegmatites intruded into migmatite gneiss, banded gneiss, diorite and granite. Petrographic studies revealed primary constituent minerals such as K-feldspar, quartz, plagioclase, muscovite, biotite and opaque minerals in the pegmatite. Secondary minerals obtained are illite, kaolinite and goethite. Occurrence of ordered and well crystalline kaolinite was facilitated by weathering of feldspathic, micaceous and accessory minerals as shown by X-Ray Diffractometric studies. Kaolinite was the main secondary mineral while illite and goethite occurred in subordinate amount. This study generally showed moderate to intense degree of weathering
FORECASTING DISTRIBUTED DENIAL OF SERVICE ATTACK USING HIDDEN MARKOV MODEL
Get PDFDistributed denial of service (DDoS) attack bombards the network with loads of packets and requests that consumes the system resources in terms of time, memory, and processors. This paper presents a proposed method for forecasting DDoS in networks. The proposed model employs hidden Markov model (HMM) to forecast DDoS attacks. The method uses the inherent characteristic features of DDoS to determine the observable states of the system.To avoid intractable computations, Kullback-Leibler divergence algorithm was employed to reduce the number of observable states to three. The proposed model is formulated and trained through experiments using DARPA 2000 data set and the preliminary resultsshows that the characteristic features of the DDoS and the entropy concept can be used to formulate an HMM to predict DDoS
DEVELOPMENT OF A VIBRATORY HONEY EXTRACTOR
Get PDFExtraction of honey from honey comb is extracted predominantly using either traditional method or the mechanical screw press method which generates a problem of crushing the comb along with the extract. This creates an additional cost of separating unwanted materials in the extract. To solve this problem for stakeholders in the honey business worldwide, a vibratory honey extractor was conceived, designed and fabricate. The machine was made of stainless, mild steel and plastic materials. The machine has a capacity of 2.5 Kw and operates at speed and frequency of 483 rpm and 50 Hz respectively. The machine was able to attain an extract of 98.9% a value far better than the centrifugal method within 40 minutes of operation. A reduction to 0.21 of the initial weight of honey extraction was obtained at an average extraction rate of 7.36g /min. The honey extracted was good quality given the best acceptable value for all stakeholders in the honey business industries
LIFE-CYCLE COST ANALYSIS OF RECLAIMED ASPHALT PAVEMENT FOR SUSTAINABLE ROAD REHABILITATION
Get PDFThe construction of pavements requires a significant amount of non-renewable materials and energy. Recycling of asphalt pavements is a valuable approach for technical, economic and environmental reasons. The use of reclaimed asphalt pavement (RAP) is being favoured over virgin materials due to increasing cost of asphalt, the scarcity of quality aggregates and the pressing need to preserve the environment. This paper present a life cycle cost analysis of recycled pavement material for sustainable road rehabilitation on Jabulani Selepe road in Bethal, Mpumalanga Province of South Africa. Long term cost effects of recycled materials was determined in pavement design; life-cycle cost analysis (LCCA) was carried out on recycled materials, alternative recycling materials and conventional method. The present worth of cost (PWOC) for recycling and conventional method was used to determine the most viable option for construction and maintenance. Agency cost, initial rehabilitation, maintenance, future and salvage cost while the users cost which include construction delays, accident cost, time and vehicle operating cost was done. The result showed that LCCA identifies recycled RAP as the lowest cost pavement alternative. The PWOC for RAP and alternative recycling material was 50.90% and 41.48% respectively when compared with conventional method. Thus, using large amount of RAP could turn these asphalt mixes into good alternative to hot mix asphalt in environmental terms and cost-effective means to road rehabilitation than that of a conventional project
GEOPHYSICAL INVESTIGATION OF PROPOSED DAM SITE ALOMG RIVER ADUNIN, OGBOMOSO, SOUTHWESTERN NIGERIA.
Get PDFABSTRACT
Dams are vital structures that store water for consumption, irrigation, electricity production and industrial purposes.The design and construction is very important to prevent the collapse of the structure .Thirty (30) Vertical Electrical Sounding points were investigated. Very Low Frequency profiling at 5m inter station along five profiles were carried out. The interpretation of geophysical data were achieved using the following software; Res 2D, Win Resist, Surfer 11, Arc GIS 3.3 and Excel. Six resistivity sounding curve types were obtained from the study area and these are the H, HA , KH, HKH, and KHA curves. The geologic sequence beneath the study area is composed of top soil, weathered basement, fractured basement, and fresh basement. The topsoil is composed of clayey-sandy and sandy-lateritic hard crust with resistivity values ranging from 339-1971 ohm-m and thickness of 0.7-1.3 m. The weathered basement resistivity is within the range of 98-3026 ohm-m and thickness value of 0.3-7.0m.The fractured basement layer resistivity values vary from 163–4049 ohm-m while its thickness ranges from 2.7 to 17m. Fresh basement has resistivity value range of 228 to14793 ohm-m.
The bedrock is highly fractured beneath the river axis and extended toward the left abutment while fresh basement is closer to the surface at the right abutment.The fractures beneath the proposed dam axis may pose serious threat to the dam in term of future seepage. The dam should be shifted toward the right abutment by 20m and excavation should be made up to depth of about 5m, the materials so removed could be used for the construction of the embankment and the filter materials
OPTIMIZATION OF CHAR IN THE PYROLYSIS OF PALM KERNEL SHELL USING RESPONSE SURFACE METHODOLOGY
Get PDFPalm oil production yields a considerable quantity of palm kernel shell (PKS). This is locally burnt as fuel for domestic cooking as well as in blacksmith and goldsmith operations. Medium-grade fuel such as char can be derived from PKS through pyrolysis. The optimization of the char yield was investigated using a central composite design of the response surface methodology in a batch reactor. A three -factor three-level design comprising the reaction temperature and provenance were taken as quantitative variables, while varieties a qualitative variable and yield was taken as the response. This study optimized char yield from palm kernel shell (PKS)through pyrolysis. Increasing reaction temperature generally decreased char yields. Variety type, reaction temperature, and provenance all significantly (p < 0.05) affected char yields for both Dura and Tenera varieties studied. The char yield obtained from Tenera variety was greater than Dura variety. The optimized temperature for both Tenera and Dura varieties was 400oC with yield of 46.85 and 42.68 % respectively, while Odeda provenance representing derived savannah provenance was the best location producing the optimal yield
DESIGN AND CONSTRUCTION OF A SIMPLE RAINFALL SIMULATOR FROM LOCALLY AVAILABLE MATERIALS
Get PDFRainfall simulator is an important instrument for producing artificial rainfall for the determination of soil loss from a catchment over a given period of time. The instrument is rarely available in most Nigeria Universities for practical demonstration for students and research in Soil and Water Conservation Engineering. This is due to high cost of the rainfall simulator and materials that are commonly used for the construction of rainfall simulator are not readily available or expensive in developing countries. In this study, a pressurized rainfall simulator was designed and constructed using the locally available materials mainly PVC pipe, shower rose and a pump for supplying water to the simulator for its operation. The main-pipe receives water from the pump and supplies it to the laterals. The laterals supply water to the distribution pipe which passes it to the shower rose. One hundred shower roses on ten laterals spray water to the ground surface through 2 mm openings. The simulator was 3 by 3 m and all the components are detachable for portability. The simulator rests on an adjustable frame which could be varied from 1 to 2 m height. The uniformity coefficient and drop velocity from the simulator during the performance test were 84.4 % and 8.156 m/s, respectively. The results of uniformity coefficient and drop velocity were within the range. The intensity of water dropping from the simulator depends on the inflow rate of water which could be regulated by the control tap fixed to the inlet main-pipe
IMPORTANCE OF AGRICULTURAL RESIDUES (CORN COB AND RICE HUSK ASH) TO CONSTRUCTION INDUSTRY IN NIGERIA: A REVIEW
Get PDFAgricultural residues are residues generated from agricultural processes. It has been discovered that the combustion of agricultural residues like corn cob and rice husk to ashes have pozzolanic properties, which means the sum of SiO2, Al2O3, and Fe2O3 composition that meet the 70% minimum requirement according to ASTM C618-12 for a material that can partially replace cement as binding agent in construction works. The discussion of the review is on the method of chemical analysis, effectiveness, benefits, and recommended solutions on the use of corn cob and rice husk ash as alternatives to cement
QUALITY ASSESSMENT OF WATER SUPPLY IN MURTALA MUHAMMED INTERNATIONAL AIRPORT, LAGOS, NIGERIA
Get PDFThis research assessed the quality of water and by implication the functionality of the treatment plant units in Murtala Mohammed International Airport, Ikeja, Nigeria. Raw water samples were collected at eight different points from the plant to the end users for three consecutive months. Physico-chemical properties of collected samples were analysed using standard methods and compared with the World Health Organization (WHO) standard. The values of properties obtained for plant raw and treated water ranged from .19 - 7.4, 24.60 - 26.00oC, 3.79- 0.00 NTU, 33.30-16.70Hazen,0.17 -0.00mg/l and 36.7 -44.30 ppm, for pH, temperature, turbidity, hazencolour, iron content, total dissolved solid respectively. While the values obtained for total hardness, calcium hardness, magnesium hardness, residue chlorine, odour, electrical conductivity, nitrate, BOD and Dissolved Oxygen, were 7.3 -5.7mg/l,3.7 -3.00 mg/l3.7-2.7mg/l,0.00 -0.00mg/l,46– 72µs/c, 0.59 - 0.56 mg/l, 3.23 - 4.17mg/l and 2.66 - 2.75 mg/l respectively. The values of parameters for the treated water were in all cases always better than those obtained for the raw water. All the physico-chemical properties obtained for the treatment line were within WHO standard except for raw water pH whose value was lower than the recommended WHO value. This observation showed that the treatment units improved the quality of the treated water and it is safe to use as potable water
HELMET USE AS A SAFETY TOOL AMONG MOTORCYCLE RIDERS IN IBADAN, OYO STATE, NIGERIA
Get PDFThis work studies helmets use as a safety tool among motorcycle riders in Ibadan, Oyo state, Nigeria. The instrument of data collection was a structured interviewer administered questionnaire on 400 motorcycle riders at Mokola and Sango areas, Ibadan. 330 responses were obtained to give a return rate of 82.5%. The analysis of the results showed that the frequency of helmet use in the study areas is 77.6% and that of non-user is 22.4%. 80% of the respondents felt that helmet use should be mandatory while only 20% felt that it should be at the discretion of riders. 150 (45.5%) respondents have ever been involved in motorcycle accidents out of which 94 (62.7%) were involved in head injury accidents. Up to 86 (91.5%) of these were involved in head injury accident before the introduction of legislation for compulsory crash helmet wear by motorcyclists in Nigeria while only 8(8.5%) were involved in the accident after the legislation of the law. This shows a decrease in head injury accidents after implementation of crash helmet law. Hence, there is need to strengthen existing legal enforcement of helmet use and ensure the availability of quality helmet to non-user both the commercial and private motorcyclists