LAUTECH Journal of Engineering and Technology (LAUJET)
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FORCED RESPONSE VIBRATION OF SIMPLY SUPPORTED BEAMS WITH AN ELASTIC PASTERNAK FOUNDATION UNDER A DISTRIBUTED MOVING LOAD
Get PDFIn this study, the response of two homogeneous parallel beams with two-parameter Pasternak elastic foundation subjected to a constant uniform partially distributed moving force is considered. On the basis of Euler-Bernoulli beam theory, the fourth order partial differential equations of motion describing the behavior of the beams when subjected to a moving force were formulated. In order to solve the resulting initial-boundary value problem, finite Fourier sine integral technique and differential transform scheme were employed to obtain the analytical solution. The dynamic responses of the two beams obtained was investigated under moving force conditions using MATLAB. The effects of speed of the moving force, layer parameters such as stiffness (K_0) and shear modulus (G_0 ) have been conducted for the moving force.Various values of speed of the moving load, stiffness parameters and shear modulus were considered. The results obtained indicates that response amplitudes of both the upper and lower beams increases with increase in the speed of the moving load. Increasing the stiffness parameter is observed to cause a decrease in the response amplitudes of the beams. The response amplitudes decreases with increase in the shear modulus of the linear elastic layer
SYNTHESIS AND CHARACTERIZATION OF MIXED LIGAND Mn(II), Co(II), Ni(II) and Cu(II) COMPLEXES OF SOME HYDRAZONES AND NITROGEN DONOR LIGANDS
Get PDF Mn(II), Co(II), Ni(II) and Cu(II) mixed ligand complexes of some Benzoyl hydrazones (hydrazide Schiff bases) with 1,10-Phenanthroline (Phen), 2,2?-bipyridine and ethylenediamine(en) were synthesized and characterized using metal analysis, molar conductivity, magnetic susceptibility, electronic spectra, infrared measurement and antimicrobial activity. The percentage metals of the complexes are in close agreement with their corresponding theoretical values. The molar conductance of some of the complexes that were soluble in nitromethane reveals that only [Co(H1L)2Bipy]Cl2 is a 1:2 electrolyte while [Cu(Phen)(H1)](NO3)H2O, [Cu(Bipy)H1L]NO3, [Cu(Phen)H1L]NO3, [Cu(H1L)(H1A)(NO3)H2O]NO3, and [Cu(H1HY)(H1A)(NO3)H2O].NO3.2H2O are 1:1 electrolyte. The electronic spectra displayed bands which were assigned to ???*, n??*, Charge transfer and d-d transitions. From the d-d transitions in the visible region of the spectra, it was suggested that these complexes have four-, five- and six- coordinate stereochemistries. The proposed geometries were backed up by the observed magnetic moments which were in line with the expected or theoretical values. The infrared spectra gave bands that were assigned to ?(NH), azomethine ?(C=N) and ?(C=O) vibrational frequencies. The shift in the ?(C=O), ?(N-N), ?(NH), ?(C-N) and ?(C=N) bands in the spectra of the complexes reveals that there is coordination of the ligands to the metal centre. The complexes compared favourably well with Gentamicin and Ketoconazole with respect to antibacterial and antifungal activities respectively
BIODIESEL PRODUCTION FROM PALM KERNEL OIL USING BENTONITE CLAY-SUPPORTED FE-CO NANOCATALYST
Get PDFThis study is focused on the development of a heterogeneous Fe-Co bimetallic nanoparticle on Pindiga bentonite clay support to be used in the production of biodiesel. The local clay was beneficiated and used in the preparation of catalyst by wet impregnation method. The X-ray Fluorescence analysis (XRF) of the bentonite clay showed the presence of several metals and metallic oxides with good catalytic effect. Characterization of the prepared catalyst using Fourier Transform Infared Ray (FTIR), Energy Dispersive Spectrometer, (EDS) X-Ray Dispersion (XRD) and Scanning Electron Microscopy (SEM) confirmed the functional groups, elemental compositions, crystallinity, and morphology of the catalyst respectively. The catalyst was evaluated in biodiesel production using Box-Behnken optimization by varying the methanol: oil mole ratio, reaction temperature, reaction time, and catalyst concentration. An optimum yield of biodiesel (93.8 %) was obtained at process condition of 15:1 methanol: oil mole ratio, 55 °C reaction temperature, 1 h, reaction time, and 15 % (w/w) catalyst concentration. Physicochemical properties of the biodiesel produced using the developed Fe-Co/ bentonite nanocatalyst showed that the biodiesel is of good quality. This was further confirmed by the FAMEs profile. Therefore, the Fe-Co/bentonite nanocatalyst showed potential application as heterogeneous nanocatalyst for the trans-esterification of vegetable oil to biodiesel, an alternative and sustainable replacement for conventional petroleum diesel
MOISTURE ABSORPTION CHARACTERISTICS AND ADAPTIVE NEURO FUZZY MODELLING OF AMPELOCISSUS CAVICAULIS FIBER REINFORCED EPOXY COMPOSITE
Get PDFNatural fibre reinforced composite is fast becoming an important class of engineering materials due to its low cost, light weight and good mechanical properties; therefore increased natural fibre composite development is desirable. In this study, the effect of water soaking time and Ampelocissus cavicaulis natural fiber (ACNF) size factors on the water absorption characteristics of ACNF reinforced epoxy composite was investigated. The optimum membership function in Adaptive Neuro Fuzzy Inference System (ANFIS) structure that modelled and predicted the observed water absorption characteristics of the developed composite was investigated by giving consideration to minimum training error. ANFIS was also utilized to evaluate the sensitivity of ACNF reinforced epoxy composite’s water absorption characteristics to water soaking time and ACNF size factors. Results showed that developed composites’ water absorption increased as water soaking time and ACNF size increased. While optimising the ANFIS structure, the training error associated with ANFIS gauss, tri, gbell, gauss2, pi and gsig memmbership functions were 0.5171, 0.08997, 0.6706, 0.08803, 1.3770 and 0.6167, respectively. The optimum ANFIS model structured (trimf) had a coefficient of determination (R2) value of 0.99947. The water absorption characteristics of ACNF reinforced epoxy composite was most dependent or sensitive to water soaking time with a root mean squared error (RMSE) of 1.577 followed by ACNF size with RMSE of 1.753. It is concluded that ACNF reinforced epoxy composite are best applied in non-moist or dry environments
MONITORING OF PHOTOVOLTAIC PANEL IN A SOLAR-POWERED LAB-SCALE SMART IRRIGATION SYSTEM
Get PDFThe solar photovoltaic (PV) or solar panel is an active transducer whose function in the provision of solar energy cannot be overemphasised. Many solar energy systems perform poorly or fail when the properties of the PV and conditions under which they are implemented are not taken into consideration during system design. Others fail due to environmental conditions such as temperature which might degrade the power generated by the solar PV. As a way of ensuring longevity and healthy operation of the PV, there is the need to do a constant monitoring of it properties and generated power. In this work, parameters such as current, voltage, and ambient temperature of 200 W solar panel are measured in real-time and obtained values used in design of solar power for a lab-scale smart irrigation system. The PV power was determined from the measured current and voltage values using appropriate sensors which are connected to an Arduino-based microcontroller. The PV under a load-OFF test was exposed to the sun from 5:30 am to 7:10 pm. The measured solar power confirms the peak sun hour of 4.5 to 5 hours for Ilara Mokin, Ondo State, Nigeria. Load-ON implementation with a lab-scale smart irrigation testbed reveals that irrigation pumps 2 and 3 maintaining an equal distance each from the water source absorb less power compared with pump 1 at a distance more than double of pumps 2 and 3 from the water source. Thus, the distance of the irrigation pumps and sprinklers from the water source is found to play vital role in the pattern of power consumption by the irrigation system. The maximum power thresholds of irrigation pumps under various load-ON conditions were determined. The power thresholds obtained would be useful parameters for configuring the lab-scale smart irrigation controller for effective performance while the peak sun hour obtained is a useful design parameter for this work and implementation of effective solar system in Ilara Mokin and its environs
NON-COOPERATIVE GAME-BASED PARTNER SELECTION SCHEME IN USER COOPERATION NETWORKS
Get PDFThe performance of any cooperative wireless communication system depends largely on the selection of a proper partner(s) by the source node to help it in forwarding information to the destination node. In this paper, we consider the concepts of partner (or relay node) selection and power allocation for a distributed communication network. A type of non-cooperative game referred to as Trade-Off game is employed so as to jointly consider the utilities of the source and relay nodes, where in this case, the source is the node that requires help with forwarding of its information while the partner is the node that is willing to help in forwarding the source node’s information, but at a price. The approach enables the source node to maximize its utility by selecting a partner node based on (i) the proximity of the partner node to the source and destination nodes, and (ii) the price the partner node will charge for the help being rendered. Our proposed scheme helps the source locate and select the relay nodes at ‘better’ locations and purchase power optimally from them. It also aids the contending relay nodes in maximizing their own utilities as well by asking proper prices. Our game scheme is seen to converge to the unique equilibrium
EFFECTIVENESS OF ELECTRO-COAGULATION TREATMENT METHOD ON THE PHYSIO-CHEMICAL PARAMETERS AND HEAVY METALS IN RUBBER LATEX WASTEWATER
Get PDFElectrocoagulation has been employed as a treatment technique for treating various wastewaters. This study focuses on the performance of the electrocoagulation process for the treatment of rubber latex wastewater (RW) using Aluminum-Aluminum (AL-AL) and Aluminum-Carbon (AL-C) electrodes. Rubber latex wastewater (RW) was obtained locally from the plastic industry in Araromi-Obu, Ondo State of Nigeria with an initial concentration of 7.30, 28°C, 65.53mg/L and 785.23mg/L for pH, Temperature, BOD, and COD respectively and subjected to electrocoagulation using (AL-AL) and (AL-C) electrodes. Effects of electrocoagulation time and electrode types were studied and achieved under the following initial conditions of 30V, current density of 15mA, inter-distance electrodes of 1.5cm. The results revealed that this process could reduce the concentration of BOD, COD and Lead in RW. The highest removal efficiencies of 98.74% and 98.47% (COD); 82.02% and 79.12 (BOD); 90% and 83.33% (Lead), were obtained for AL-AL and AL-C electrodes respectively. From this study, it can be concluded that electrocoagulation is effective in the treatment of RW. It is recommended that Rubber producing industries could adopt this treatment method to treat their wastewater rather than disposal into the environment without treatment.
 
OPTIMIZATION OF OPERATION PARAMETERS OF A DEVELOPED DOUGH MIXER
Get PDFA mixer is essentially required for homogenizing flour and other ingredients in the bakery industry. In this research, a dough mixer was developed using a 10.5% chromium stainless-steel and its performance evaluated based on the machine parameters. The shaft speed (250?350 rpm), agitator geometry angle (45o, 60o and 90o) and number of blades (type A-5, type B-4 and type C-3) were considered as the machine parameters. The Effective mix proportion (EMP) was determined as the performance index. A Split-Plot Optimal Design was used to determine the desired variables for maximum EMP. Results show that the EMP decreases with an increase in the agitator geometry angle, irrespective of the speed of the mixing shaft. A critical behavior of the mixer was obtained at 300rpm, which indicates the homogeneous phase change stage in the mixing process. Again, the mixer performance was higher for the agitator with 5 blades and lower for the 3 blades agitator. The optimum EMP occurred for type C-3 blades, 60o geometry angle at 250 rpm with 98% desirability. These can be considered as the best configurations for a large-scale practice
TRANSVERSE RESPONSE OF AN ELASTICALLY RESTRAINED END DOUBLE-BEAM SYSTEM DUE TO A CONCENTRATED MOVING MASS
Get PDFIn this paper, transverse response of a double beam system traversed by a concentrated moving mass is investigated. The system, which is elastically restrained at both ends, consists of two identical homogeneous parallel Euler-Bernoulli beams and are continuously interconnected with a viscoelastic Winkler-type layer. Of particular interest, is the effect of the moving load on the dynamic response of the system. The solution scheme deployed involves, using series variable separable method, modified Struble’s method and differential transformation method (DTM). For the purpose of demonstrating the simplicity and efficiency of the technique, numerical examples are explored. The dynamic deflections of the beams are presented graphically and are found comparable with the existing results for the case of a moving force. The effect of various values of the mass of the moving load on the dynamic response of the beam are presented and discussed. The effects of the speed of the moving load, viscoelastic parameter and stiffness parameters are also examined
INVESTIGATION INTO PATH LOSS PERFORMANCE FOR LONG TERM EVOLUTION WITH KEY PERFORMANCE INDEX
Get PDFThis work involved investigation into path loss (PL) performance evaluation for long term evolution (LTE)with key performance index. PL model for prediction of cellular transmission, enhance spectral efficiencyrelay and channel capacity for three terrains (hilly areas with thick vegetation, hilly terrains withexceptional or uniform vegetation, and smooth terrains or rural area with low vegetation) were evaluated.PL of 114dB and 159dB were obtained for downlink distances of 5km and 20km, respectively for StandfordUniversity Interim (SUI) and Cost-231 Hata. The result shows increase in the throughput per user whencompared to the average throughput achieved in Cost-231. Again, uplink data traffic from communicationsequipment towards the network core associated with higher spectral efficiency for uplink PL are 159 and190dB, respectively for LTE systems. This is attributable to the relative distance between the transmittingand the receiving stations. Hence, higher spectra efficiency utilization for LTE is not currently feasible forLagos and other major cities in Nigeri