LAUTECH Journal of Engineering and Technology (LAUJET)
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EVALUATION OF THE EFFECT OF PHYSICAL AND MINERALOGICAL CHARACTERISTICS OF SOME ROCK TYPES ON THEIR MECHANICAL PROPERTIES (A CASE STUDY OF EKITI, ONDO AND KWARA STATE)
Get PDFThe research work studies the effect of physical and mineralogical characteristics of some rock types on theirmechanical properties. Samples of rock were collected from six locations, Egbejila and Odore (Kwara State),Ijare and Itaogbolu (Ondo State), Iyin and Awo road, (Ekiti State), in Nigeria. The physical properties (hardness,density and specific gravity), mineralogical properties (X-Ray Diffraction (XRD) and mechanical properties(Uniaxial Compressive Strength (UCS); Point Load Strength and Brittleness) were determined in the laboratoryusing the required international standard and the equipment used are Impact Testing Machine, CompressionTesting machine, Aggregate Impact Value (AIV) machine, Aggregate Crushing Value (ACV) machine, GlobalPositioning System (GPS), Cut-off Saw Machine, and Petrographic Microscope. From the results of theinvestigation, it was observed that the concentration of quartz and other minerals as indicated by the X-RayDiffraction (XRD) have influence on the highest on the mechanical properties of the rocks under study. Ijarewith the highest quartz content of 69.4% has the highest UCS of 174.4 MPa while Odore with the lowest quartzcontent of 33% has the lowest UCS of 120 MPa. Dominance of silica is range of 62.455% – 70.72%). Thephysical properties (hardness, density and specific gravity) were found to follow the same trend with themineralogical properties in influencing the mechanical behaviour of rock, most especially the UCS. Denser andharder rock samples were found to have higher UCS. Conclusively, the physical and mineralogical properties ofrock were found to correlate strongly with the mechanical properties
REVIEW OF SELECTED POZZOLANAS FOR CONCRETE PRODUCTION
Get PDFIn pursuit of producing a sustainable and durable concrete composite, there is need to incorporate some supplementary cementitious materials to modify its conventional properties. Several works have been done on the utilization of agricultural and industrial wastes as pozzolans in concrete. However, there are some naturally occurring materials that also exhibit additional binding tendency that are yet to be explored. Cement being a conventional binder in concreting undergoes hydration reaction producing lime as one of its by-products. This causes expansion thereby predisposing the composite to disintegration and hence, untimely failure. Pozzolans have the tendency of forming additional binding property when in contact with this lime in the presence of water. Lot of research has been carried out on its properties and effects in concrete. However, there have been disparities in the optimum percentage replacement of various pozzolans in concrete. This article focuses on previous findings on the utilization of pozzolans in concrete and its prospects in th
EFFECTS OF EXPRESSION PRESSURES AND DISC SHAPES ON THE EXTRACTION EFFICIENCY aOF A FRUIT JUICE EXTRACTOR
Get PDFA developed fruit juice extractor was studied for its performance. Some parameters like, expression pressures andpressure disc shapes diameters were varied to determine their effects on its extraction efficiency using ResponseSurface Methodology (RSM). Three levels of expression pressures (80 ,100 and 120 N/mm2) and three differentdiameters of its concave and convex discs pressure plates (60,80 and 100 mm) were investigated. The highestextraction efficiency of 71.95 % was obtained when the convex disc diameter was 100 mm and the expressionpressure was 120 N/mm2. Further RSM analysis showed that the linear effects of expression pressures andconvex disc diameter of the juice extractor were significant to its extraction efficiency at 5% probability (P?0.05).Also significant are the quadratic effects of concave and convex disc diameters, interactions of expressionpressures and concave disc diameters, interactions of expression pressures and convex disc diameters andinteractions of concave and convex disc diameters. These factors accounted for about 98.58 % of the variationsin the extraction efficiency of the machin
DEVELOPMENT AND PERFORMANCE EVALUATION OF A MOTORISED PLANTAIN CHIPPING MACHINE USING RESPONSE SURFACE METHODOLOGY
Get PDFA lot of drudgeries and unhygienic processes are involved in manual chipping of plantain. These problemsnecessitated the development of a motorised plantain chipping machine with a capacity of 450 kg/h. Themachine is made up of a cutting device, a feeding mechanism, the support frame and an electric motor as asource of power. The cutting mechanism consists of the stainless steel blades, a connecting rod, a guideframe for the blades and pulleys. The blades are arranged perpendicular to the plantain fingers. Duringperformance evaluation of the chipper, the effects of the number of cutting blades, inclination of the anglesof the cutting blades and cutting speed as they affected the chipping efficiency were investigated. ResponseSurface Methodology was used in the experiments because it uses very few experimental runs to describe howthe test variables affect the response. It also helps to determine the inter-relationships among the testvariables on the response and also helps to describe the combined effects of all the test variables on theresponse. The highest chipping efficiency of 70% was obtained when the machine was operated at the speedof 975 rpm, with a blade angle inclination of 300and with nine cutting blades. Generally, it was found thatthe chipping efficiency increased as the number of cutting blades are increased. Also the chipping efficiencyincreased with the speed of the machine but was not affected by the inclination angles of the blades. Thelinear effects of speed, the linear and quadratic effects of the number of blades significantly affected thechipping efficiency of the machine at 5% probability
ANAEROBIC DIGESTION OF COW MANURE: INFLUENCE OF HYDRAULIC RETENTION TIME ON BIOGAS YIELD AND PROPERTIES OF DIGESTATE
Get PDFThis research paper assessed the influence of hydraulic retention (HRT) time on biogas yield and the properties of digestate during anaerobic digestion. Anaerobic digestion of cow manure was simultaneously digested in a custom built 20L digester at different HRT’s of 10, 18, 28, 38, 50 and 60day. The study showed HRT had substantial influence on biogas yield and on the properties of digestate. An average biogas yield of 1.6m3/KgVSadded to 3m3/KgVSadded was obtained. The elemental content of carbon, hydrogen, and nitrogen of the resultant digestate reduced from 35.6w/w% to 19.9w/w%, 6.3w/w% to 2.8w/w%, and 2.1w/w% to 0.8w/w%, respectively, after a 60day HRT. Consequently, the higher heating values reduced from 15.1MJ/kg to 3.5MJ/kg. Also, the carbon-to nitrogen ratio was between 17.9 and 24.8 when compared to that of cow manure, while the hydrogen-to carbon ratio was in the range of 1.4 to 1.8. The digestate could be used as a fertilizer, alternatively as a precursor for biofuel production
IMPACT OF ELEMENT LENGTHS AND SPACINGS ON THE PERFORMANCE CHARACTERISTICS OF YAGI-UDA ANTENNA
Get PDFThis work examines the impact of element lengths and spacing on the performance behaviours of Yagi-Uda antenna. Four Yagi-Uda antenna types are used as candidates for numerical investigation including Yagi-Uda antenna of uniform lengths of directors with uniform spacings (YUDUS), Yagi-Uda array of uniform lengths of directors with non-uniform spacings (YUDNS), Yagi-Uda array of varying lengths of directors and uniform spacings between directors (YVDUS), and Yagi-Uda antenna varying length of directors with non-uniform director spacings (YVDNS). Upon utilizing method of moments procedure, far-zone radiation field, directivity, front-to-back ratio, and side lobe radiation emerge and are therefore utilized as performance metrics for analyzing the behaviour of those Yagi-Uda antenna types. It is observed that YVDNS exhibits better directive main lobe radiation and lower side lobe radiation than others. It is observed also that YVDNS has maximum front-to-back ratio which suggests better electromagnetic energy radiation than others. These characteristics properties of YVDNS design commend the antenna for a number of practical applications more than any other type of Yagi-Uda antenna
INVESTIGATION OF THE INFLUENCE OF COW DUNG ASH AS FILLER AND POLYETHYLENE TEREPHTHALATE AS BITUMEN REPLACEMENT IN ASPHALT CONCRETE
Get PDFThis study investigated the influence of Cow Dung Ash (CDA) and Polyethylene Terephthalate (PET) as partial replacement of filler and binder respectively on the volumetric and Marshall Properties of asphalt concrete in separate mixes. In one mix, the filler was partially replaced with CDA at 4, 8, 12, 16 and 20% while for the other mix, the bitumen was partially replaced with PET at 3, 6, 9, 12 and 15 %. Asphalt briquettes were produced in accordance with marshal procedure for wearing course of medium traffic roads and marshal stability, while properties of the mixes were obtained from the flow and volumetric parameters. Results showed that replacing the filler between 4% and 8% with CDA has the potential for use in asphalt concrete. Also, for mixes with PET replacement, percentages between 6 and 15% can be considered for wearing course of medium trafficked roads
ICT AS A CHANGE AGENT FOR QUALITATIVE HIGHER ADULT EDUCATION IN NIGERIA: A CASE STUDY OF OYO STATE
Get PDFThis study appraised the role of Information and Communication Technology (ICT) as a change agent in qualitative higher adult education programmes in Oyo State. It identified the available ICT facilities, determine the extent of utilization of ICT and ascertain the strategies for practical use and implementation of ICT for such programmes. Three research questions and hypotheses guided the study with a descriptive survey design and a questionnaire as a data collection instrument. Four experts in the field validated the instrument while data generated and collated was tested using the Cronbach statistics. The overall reliability score of the instrument's rating was 0.908. Findings showed that the identified ICT facilities available, as well as their extent of utilization in these programmes for higher adult education programmes, were accepted as being appropriate. Similarly, the strategies adopted for the effective implementation and use of ICT in higher adult education programmes in the State were considered suitable for the application
MODIFIED ABOODH HOMOTOPY PERTUBATION METHOD FOR SOLVING NONLINEAR GAS DYNAMIC EQUATION
Get PDFIn this paper, we present a reliable combination of Aboodh Transform and Modified Homotopy perturbation method to solve nonlinear gas dynamic equations. Some problems were solved to demonstrate the capability and reliability of the mixture of Aboodh Transform and Modified Homotopy perturbation method. We have compared the result obtained with the available Laplace Transform New Homotopy Perturbation Method solution and homotopy perturbation method of solution which is found to be exactly the same. The result revealed that the combination of the Aboodh Transform and Modified homotopy perturbation method is practically well appropriate for use in such problems
BINARY MORPHOLOGICAL IMAGE PROCESSING ALGORITHM IN COMPUTER VISION APPLICATION
No full textBinary morphological image processing algorithm in computer vision application is reported. The algorithm is simple in implementation and efficient in computation. It is divided into two main parts, firstly method of enhancing occurring defects on the surface of manufactured product is introduced and secondly binary morphological filtering technique is developed to remove noise and other artifacts completely from the product binary images before feature extraction. It has been shown that the algorithm produces good results when tested on a number of manufactured products. The results presented in real images of a ceramic wall tile and biscuit shows the effectiveness of the algorithm