PRODUCTION OF BIODIESEL FROM SOME VEGETABLE OILS

Biodiesel is becoming prominent among the alternatives to conventional petro-diesel due to economic,environmental and social factors. The quality of biodiesel is influenced by the nature of feedstock and theproduction processes employed. High amounts of free fatty acids (FFA) in the feedstock are known to bedetrimental to the quality of biodiesel. In addition, oils with compounds containing hydroxyl groups possesshigh viscosity due to hydrogen bonding. American Standards and Testing Materials, (ASTM D 6751)recommends FFA content of not more than 0.5% in biodiesel and a viscosity of less than 6 mm2/s. Thephysico-chemical properties of palm kernel oil and coconut oil were assessed for their potentials in biodiesel.The properties of palm kernel oil and coconut oil were compared with those of palm from literature whilethat of biodiesel were compared with petro-diesel, ASTM and European Standards (EN14214). Resultsshowed that high amounts of FFA in oils produced low quality biodiesel while neutralized oils with lowamounts of FFA produced high quality biodiesel. The quality of biodiesel from palm kernel oil and coconutoils was improved greatly by neutralising the crude oil

Network traffic analysis for threats detection in the Internet of Things

As the prevalence of the Internet of Things (IoT) continues to increase, cyber criminals are quick to exploit the security gaps that many devices are inherently designed with. Users cannot be expected to tackle this threat alone, and many current solutions available for network monitoring are simply not accessible or can be difficult to implement for the average user, which is a gap that needs to be addressed. This article presents an effective signature-based solution to monitor, analyze, and detect potentially malicious traffic for IoT ecosystems in the typical home network environment by utilizing passive network sniffing techniques and a cloud application to monitor anomalous activity. The proposed solution focuses on two attack and propagation vectors leveraged by the infamous Mirai botnet, namely DNS and Telnet. Experimental evaluation demonstrates the proposed solution can detect 98.35 percent of malicious DNS traffic and 99.33 percent of Telnet traffic for an overall detection accuracy of 98.84 percent

Vitamins A, C and Lycopene Contents of Some Varieties of Tomato and Pepper in the Southwest Region of Nigeria

The concentrations of vitamin A, C and lycopene were determined in some varieties of Lycopersicum esculentum (Plum tomato, Marmande tomato, Beefsteak tomato and Cherry tomato) and capsicum sp. (fresh Cayenne pepper, Bell pepper, Green pepper, Sweet pepper, Hot pepper and Dry cayenne pepper). The ethanolic extracts of the varieties of tomato and pepper were prepared and the vitamin A and lycopene contents were quantified by separating funnel technique, while the concentration of vitamin C was determined by titration technique in the aqueous extract. The concentrations of vitamin A and lycopene were significantly increased (p<0.05) in Plum and Cherry tomatoes. Vitamin A concentration in the various pepper fruits increased significantly (p<0.05) in the order: green pepper<sweet pepper=hot pepper<bell pepper< dry cayenne<cayenne. Significant increases (p<0.05) were presented only in the Vitamin C contents in the green, hot and cayenne pepper fruits with no changes (p>0.05) among these pepper. Lycopene concentrations were significant increased (p<0.05) in the order of green pepper<sweet pepper<bell pepper<cayenne pepper. The finding of the study indicated that the Plum and Cherry tomato fruits, and Bells and fresh Cayenne pepper fruits would have better anti-oxidative capabilities. Therefore, the consumption of the combination of these tomato and pepper fruits as recipes in soup or stew making may boost the endogenous anti-oxidative status. Keywords: Lycopersicum esculentum, capsicum species, Vitamin A, Vitamin C, Lycopene, anti-oxidative capabilities, recipes and boost the anti-oxidative status

Harmonics mitigation on industrial loads using series and parallel resonant filters

Most industrial loads are inductive in nature and therefore absorb Volts Ampere Reactance (VARs) leading to lagging power factor. Some inductive loads also produce current and voltage signals with frequencies in integer multiples of the 50 or 60 Hz fundamental frequencies called harmonics. Harmonics in power system causes several problems ranging from overheating, premature equipment failure, false tripping of protective relays resulting in unnecessary down time in industrial production. This work compared the use of series and parallel resonant harmonic filters in suppressing harmonics using Simulink model of the power system of NICHEMTEX, a Textile industry in Nigeria as a case study. Mathematical analysis representing current harmonics distributions on industrials loads with and without capacitor banks were presented. From the analysis, series resonant filter mitigated the total harmonic distortion from 30.080% to 3.460%. The installation of capacitor bank along with the series resonant filter in the industrial facility, further reduced the total harmonic distortion to 0.001% and power factor compensated from 0.860 to 0.894.However, the use of parallel resonant filter mitigated the harmonic distortion to 8.107% and a reduction in the power factor from 0.860 to 0.840. With the parallel resonant filter connection with the capacitor bank, harmonic distortion was mitigated to 0.140%, and the power factor reduced to 0.553, the value which is very low. Hence, it is observed that for this sample case, the use of series resonant filter mitigated the harmonics distortion and maintained power factors within the acceptable IEEE standard values.Keywords: Industrial inductive loads, Harmonics, Harmonic distortions, Power factor correction, Series resonant filter, Parallel resonant filte

FREQUENCY AND VOLTAGE RESPONSES OF GAS-FIRED DISTRIBUTED GENERATION SYSTEM TO LOAD

Research has shown that addition of loads to a distributed generation (DG) system operating either in stand-alone mode (SAM) or grid-connected mode (GCM) has impacts on its operations. This paper analyzed the voltage and frequency responses of the DG when operated in stand-alone and grid-connected modes under load variations. Mathematical equations showing the characteristics of the DG under varying loads with the two modes were developed. The equations were modeled using MATLAB in Simulink environment. By applying gradual and sudden loads using 2MW DG and an 11kV distribution grid network, the frequency and voltage responses under the two modes were calculated. The results showed that with gradual load addition from 10 to 100 % loading, the output frequency varied from 49.72 to 49.27 Hz (-0.56 to -1.46 %) for SAM while it varied for GCM from 49.90 to 49.44 Hz (-0.20 to -1.12 %). Output voltage varied from 376 to 232.9 V (-6.0 to -41.78 %) for 10 to 100 % load respectively for SAM while it varied from 387.7 to 268.3 V (-3.08 to -32.93 %) for GCM. For sudden load additions, the output frequency variation was between 49.39 to 49.25 Hz (-1.22 to -1.5 %) for 25 to 100 % load for SAM while that of GCM was between 49.51 to 49.43 Hz (-0.98 to -1.14 %); voltage variation was 271.7 to 190 V (-32.08 to -52.5 %) for 25 to 100 % load respectively for SAM while that of GCM was 294.2 to 219.9V(-26.45% to -45.03%). The results revealed that the frequency with gradual and sudden load additions for SAM and GCM varied outside the operational limit of 49.75-50.25 Hz () except in the case of 10 % load under gradual load addition in GCM. However, the frequency and voltage variation are less in GCM than SAM with gradual and sudden load addition

Finite Element Modeling of Resonance in Polycrystalline Materials for Resonance Ultrasound Spectroscopy

Validation of models that predict the performance of aerospace engine materials depends on the ability to obtain accurate single crystal elastic constants. Resonance Ultrasound Spectroscopy (RUS) is a nondestructive technique in which the natural resonances of a material are utilized to obtain these constants. Traditional RUS utilizes an analytic approach to determine the resonance frequencies of a specimen given an initial guess set of elastic constants. A nonlinear optimization process then fits the elastic constants to experimentally measured data. This approach is limited both in its ability to handle specimens with complex geometry and to handle polycrystalline materials. These more complex scenarios can be approached by utilizing a finite element forward model to obtain sample resonances. A finite element forward model is being developed utilizing COMSOL Multiphysics to compute specimen resonance frequencies. Elastic constants are obtained utilizing a bounded nonlinear optimization routine in MATLAB by way of COMSOL\u27s LiveLink for MATLAB interface. Validation of this forward model has been performed on single crystal specimens, including a nickel superalloy parallelepiped and a fused silica cylinder with a chamfer, ultimately producing lower residual error after optimization than the traditional RUS approach. Model validation is also being performed on a Nickel Aluminide (NiAl) bicrystal. This paper presents the details of this validation process. Also presented is an examination of error sources and the impact they can play in the ability to accurately obtain elastic constants

Fatigue Behaviour of Medium Carbon Steel of Different Grain Structures

This paper investigated the effect of heat treatment operations on the fatigue resistance of low carbon steel. Specimens after preparation for fatigue testing were subjected to annealing, normalizing and quenching heat treatment. Results show that the annealed specimen had the largest number of cycles to failure, indicating a high fatigue resistance. The microstructure of the specimens was examined in other to corroborate the obtained property with the microstructure. When compared with the untreated specimen, the annealed specimen (with optimum fatigue resistance) shows a large grains size of pearlite which was distributed across the entire surface of the microstructure. Generally, it was found that the size and distribution of specimens’ grains affect the resistance of the low carbon steel to fatigue failure. Keywords: fatigue, low carbon steel, heat treatment, microstructur

Semi analytic method for solving infectious disease model

In this paper, we present a deterministic model that captures the essential dynamics of infectious diseases. Differential Transform Method (DTM) is applied to attempt the series solution of the model. The efficiency of the DTM in solving the model is confirmed by classical fourth-order Runge-Kutta method implemented in Maple 18. The comparisons between the DTM and Runge-Kutta (RK4) solutions were made and there exists positive correlation between the results obtained by the two methods. The outcome of comparison between the DTM and RK4 validates the potential of the DTM in coping with the analysis of modern epidemics

NUMERICAL SOLUTION OF VOLTERRA INTEGRO-DIFFERENTIAL EQUATIONS BY AKBARI-GANJI’S METHOD

In this study, Akbari-Ganji’s Method (AGM) was applied to solve Volterra Integro-Differential Difference Equations (VIDDE) using Legendre polynomials as basis functions. Here, a trial solution function of unknown constants that conform with the differential equations together with the initial conditions were assumed and substituted into the equations under consideration. The unknown coefficients are solved for using the new proposed approach, AGM which principally involves the application of the boundary conditions on successive derivatives and integrals of the problem to obtain a system of equations. The system of equation is solved using any appropriate computer software, Maple 18. Some examples were solved and the results compared to the exact solutions

Physical And Mechanical Characteristics Of Charcoal, Sawdust And Sugarcane Bagasse As Solid Fuel Materials

This paper reports on the physical and mechanical characteristics of briquettes produced from charcoal, sawdust and sugarcane bagasse using molasses with sodium silicate as binders. Charcoal, sawdust and sugarcane bagasse were mixed in respective ratio of 20:20:60, 20:30:50, 20:40:40, 20:50:30 and 20:60:20. The briquettes were produced using Budenberg dial gauge compression machine, with pressure of 64 MPa at 120 seconds dwell time. Physical properties (relaxation ratio, compaction ratio and shattering index) and mechanical property (compressive strength) of the produced briquettes were investigated. Results show that briquette with sample composition of 20:30:50 has better physical properties with relaxation ratio of 1.562, compaction ratio of 7.573 and shatter index of 99.6%, while sample with ratio 20:40:40 has highest compressive strength of 55.43 kN/m2