A modified chord Newton’s method for high-dimensional algebraic equations

M. Y. Waziri and H. Aisha

There is a great deal of interest on reducing overall computational budget of classical Newton’s method for solving nonlinear systems of equations. The appealing approach is based on chord Newton’s but the method mostly requires high number of iteration as the dimension of the systems increases. In this paper, we introduce a new procedure that will reduce the well known shortcoming of Newton method. Our approach was implemented on some benchmarks nonlinear systems which show that, the proposed method is very encouraging.

The physical properties relevant to the design and manufacture of handling, storage and processing equipment were determined under varying grain moisture content for 'Asontem' cowpea variety between 8.07%wb and 22.54%wb. The length, width, thickness, geometric mean diameter, surface area, volume, 1000 grain mass, bulk density, true density, filling angle of repose and the static coefficient of friction increased with increasing moisture content during rewetting. In the moisture content range of 8.07% w.b. to 22.54% w.b., the length, width and thickness increased non-linearly from 7.00 to 7.29mm, 6.27 to 6.33mm and 4.54 to 4.69mm, respectively. The geometric mean diameter, surface area, volume and 1000 grain mass increased from 5.83 to 5.99mm, 107.03 to 113.09mm², 104.45 to 113.45mm³ and 120.15 to 130.58g, respectively while bulk density and true density decreased non-linearly from 752.95 to 682.93kg/m³ and 1219.90 to 1161.39 kg/m³, respectively. The filling angle of repose increased non-linearly from 27.81 to 32.31 while the coefficient of static friction also increased non-linearly from 0.29 to 0.41, 0.31 to 0.45 and 0.25 to 0.32 for plywood, mild steel and rubber respectively. Mild steel offered the highest coefficient of friction followed closely by plywood then rubber.

Optimal ANN parameters for the predictive model of uncoated carbide tool wear when turning NST 37.2 steel

T. B. Asafa and D. A. Fadare

We present an artificial neural network (ANN)-based predictive model for the estimation of flank and nose wear of uncoated carbide inserts during orthogonal machining of NST (Nigerian steel) 37.2. Turning experiments were conducted at different cutting conditions on a M300 Harrison lathe using Sandvic Coromant uncoated carbide inserts with ISO designations SNMA 120406 using full factorial design. Cutting speed (v), feed rate (f), depth of cut (d), spindle power (W), and length of cut (l) are the input parameters to both the machining experiments as well as ANN prediction model while the flank wear (VB) and nose wear (NC) were used as the output variables. Nine different structures of multi-layer perceptron neural networks with feed-forward and back-propagation learning algorithms were designed based on the concept presented by Chen et al. (2007) using the MATLAB Neural Network Toolbox. The optimal ANN architecture of 5-12-4-2 with the Levenberg-Marquardt training algorithm and a learning rate of 0.1 was obtained using Taguchi method of experimental design. The results of ANN prediction show that the model generalized well with root mean square errors (RMSE) of 3.55 % and 4.67 % for flank wear and nose wear respectively. With the optimized ANN architecture, parametric study was conducted to show the effects of the cutting parameters on the tool wear. The ANN predictive model captures the dynamic behaviour of the tool wear and can be effectively deployed for online monitoring process.

A comparative experimental study between the biodiesels of karanja, jatropha and palm oils based on their performance and emissions in a four stroke diesel engine

H. K. Amarnath, Sachin A. Bhat and Ruturraj Paatil

The depletion of supply of fossil fuels and their increased cost has driven the search for alternative sources of energy. One of the best alternatives is mainly biodiesels obtained from different vegetable oils. The present study focuses on comparison of performance and emissions of a 4-stroke diesel engine run on three different biodiesels viz. Karanja, Jatropha and Palm separately. Short-term engine performance tests are conducted on a single-cylinder, four-stroke, direct-injection, variable compression ratio, compression ignition engine using the three biodiesels mentioned above at torques of 0, 5, 10, 15, 20 Nm, compression ratios of 14, 15, 16, 17, 17.5, 18 and injection pressures of 150, 200, 250 bar. The performance of the three biodiesels is compared on the basis of brake specific fuel consumption, brake thermal efficiency and exhaust gas temperature and the emissions compared are hydrocarbons and oxides of nitrogen. It is found from the results that biodiesels differ very little from diesel in performance and are better than diesel with regard to hydrocarbon emissions. However oxides of nitrogen are found to be higher for biodiesels but not significantly higher when compared with diesel.

Real time fault analysis and loss reduction of transmission line using GSM technology

M. S. Sujatha and M. Vijay Kumar

Abstract:

Designing and implementing commercial as well as industrial systems based on Wireless robust communication has always been a prominent field of interest among many researchers and developers. The proposed GSM based system always calculates the utilization factor and plant efficiency and communicates to the subsystem. The sub system program architectures can be defined in such a way that, the set points can be altered (only increases) as per the transmission input. This paper presents design and implementation methodology of a real time fault analysis and loss reduction on transmission line using GSM Technology. Using GSM as the medium for fault analysis provides a cost-effective, wireless, always-connected and bi-directional communication as a message or data. The line losses expected at various levels are predefined and beyond that to be notified by smart data acquiring system, which can act fast and alert the electricity authorities about the same.

Fuzzy logic approach to airplane precision instrument approach and landing

Vahed Tavakoli Zadeh

Abstract:

In the precision instrument approach and landing of an airplane where the uncertainty is very frequent due to the high sensitivity of the activity to many factors, Fuzzy logic can be used to produce estimates which take into account the vagueness of the flight environment. In this paper an analysis of the inputs under fuzzy logic approach is considered. The success rate of landing is investigated, when the visibility, pilot experience and air speed are given by a fuzzy function. Precision instrument approach and landing simulations are used and the performance of the fuzzy based system is evaluated with fuzzy logic toolbox under MATLAB’s Simulation Block Set which provides a complete set of tools for evaluating the success rate of landing under the given inputs. Comparison of the results from the developed fuzzy based system and flight simulation results show that the proposed fuzzy engine can successfully predict the success rate of landing under the given inputs.

Biodiesel kinematics viscosity analysis of Balanite aegyptiaca seed oil

Babagana Gutti, Shittu S. Bamidele and Idris M. Bugaje

Biodiesel is a renewable and promising fuel alternatively ear marked for use in Compression Ignition (CI) engines. For it to be applicable in CI engines, there are a number of quality tests required for its certification. Kinematics viscosity is one of the most significant test properties. The viscosity difference experienced between the oil and the biodiesel produced forms the basis of an analytical method use to determining the conversion of vegetable oil to methyl ester. This paper presents the definitions, test procedure specifications, and experimental results for the kinematics viscosity of Balanite aegyptiaca oil to biodiesel. In addition, the kinematics viscosity results have been used to extrapolate the Viscosity Index (VI) values of the produced biodiesel.

Effect of friction stir welding parameters (rotation and transverse) speed on the transient temperature distribution in friction stir welding of AA 7020-T53

Muhsin J. J., Moneer H. Tolephih and Muhammed A. M.

Abstract:

Three-dimensional nonlinear thermal numerical simulations are conducted for the friction stir welding (FSW) of AA 7020-T53. Three welding cases with tool (rotational and travel) speeds of 900rpm-40mm/min, 1400rpm-16mm/min and 1400rpm-40mm/in are analyzed. The objective is to study the variation of transient temperature in a friction stir welded plate of 5mm workpiece thickness. Based on the experimental records of transient temperature at several specific locations during the friction stir welding process for the AA 7020-T53, thermal numerical simulation is developed. The numerical results show that the temperature field in the FSW process is symmetrically distributed with respect to the welding line, increasing travel speed decreasing transient temperature distribution and increasing rotational speed increase temperature distribution. Experimental data illustrates that peak temperatures are higher on the advancing side than the retreating side. Comparison with the temperature measured by the thermocouples records shows that the results from the present numerical simulation have good agreement with the test data.

Performance and emission characteristics of straight vegetable oil-ethanol emulsion in a compression ignition engine

Nandkishore D. Rao, B. Sudheer Premkumar and M. Yohan

Abstract:

This paper investigates the performance and emissions of single cylinder, naturally aspirated, compression engine using Straight vegetable oil, its micro emulsions with ethanol and diesel fuel separately. During investigation, performance and emission parameters are measured with straight vegetable oil, micro emulsions of vegetable oil and ethanol and compared with petro diesel.  The Micro emulsions are prepared to reduce the viscosity of vegetable oil. Basic properties like viscosity, calorific value, specific gravity are evaluated for all test fuels. The Straight vegetable oil (SVO) shows lower thermal efficiency, higher un-burnt hydrocarbon emissions etc. due to high viscosity and poor volatility. In long term, SVO show injector choking, fuel pump damage, fuel filter clogging etc. The emulsions of SVO with alcohol show lower viscosity, improved volatility, better combustion and less carbon deposits. The engine performance with the micro-emulsion ESVO-70 is very close to diesel fuel. Reduction in nitric oxide, carbon monoxide, and smoke emission are observed with increase in amount of ethanol in emulsion. It could be concluded that micro emulsion ESVO-70 can substitute diesel.

Abstract:

A novel Selective Weighted Linear Parallel Interference cancellation (SWLPIC) technique is proposed to reduce the interference (degrading effect) on a desired user caused by other users sharing the same channel in a Multicarrier Code Division Multiple Access (MC-CDMA) system. The SWLPIC technique cancels the interference using WLPIC on selected users whose instantaneous Signal to Interference Ratio (SIR) exceed certain threshold on Rayleigh fading channels in each subcarrier. In WLPIC the multi access interference (MAI) are estimated and cancelled based on the soft outputs of individual subcarriers. The MAI estimate of individual subcarriers is scaled by a weight before cancellation. Also, the SIR for each subcarrier is determined and an expression for the optimum threshold is derived by optimizing the approximate expression for the SIR. The interference cancelled outputs of different subcarriers are then combined to form the final decision statistic. The simulation results show that the SWLPIC technique outperforms over matched filter (MF) detector and conventional Linear PIC (LPIC). Also the performance of SWLPIC approaches weighted LPIC (WLPIC).

Abstract:

In this study, performance evaluations of solar tower system based on the environmental conditions of Kano, Nigeria is described by considering the simplified theories of the solar tower system and constructing a solar tower system by using the energy calculations, technical dimensions and materials for Enviromission (Australia) and Manzanares (Spain) solar tower power plants and testing the system at no-load conditions to determine the available power (power input). Result shows that, the enthalpy and entropy values increased for the solar tower system due to minimum losses from the system, which resulted to an increased energy and positive power input, . An attempt was made to test the solar tower system “B” at load condition by selecting a dynamo of 6W electrical output, however, no result was obtained, and this was due to the higher starting torque of the dynamo.

Abstract:

The heat transfer characteristic and performance of the flat plate air heater with and without thermal storages are studied experimentally. The mathematics models described the heat transfer of the plate solar air heater are derived from the energy equation. The implicit method of finite difference scheme is employed to solve these models. The effect of the thermal conductivity of the thermal storage on the heat transfer characteristic and performance is considered. The results obtained from the model are validated by comparison with experimental data. There is a reasonable agreement between the present model and experimental data.

Abstract:

Power system network can undergo outages during which there may be a partial or total black out in the system. To minimize the interruption of power supply to consumers, proper switching of power lines is required. Identification of power flow path in the network is the difficult task of the load dispatching centre. Practically the power system operators used the predefined rules in identifying the power flow path; sometimes it leads to cascaded outage. Hence the reason for failure of restoration may be the wrong identification of the power flow path. The scope of the proposed work is to identify the optimal power flow path using Floyd Warshall Algorithm (FWA) with additional constraints. This algorithm is selected in the shortest path algorithms because in single execution, it finds the shortest path between all pairs of vertices. Software has been created in order to identify the restoration path in a sample 5 bus system and obtained the results for a practical Chennai 230kV network.

Abstract:

Thermal properties such as specific heat, thermal conductivity and thermal diffusivity of tropical fruits provide critical information and data for the design and manufacture of equipment and machines for their processing. Literature generally abounds in information on subtropical fruits but not on tropical fruits like banana. Banana was selected because it was not processed in their dried form in Ghana. The purpose of the study was thus to provide information on the thermal properties of locally grown banana to aid in the design and manufacture of equipment for processing, handling and transportation of banana. The selected variety for the study was dried to moisture contents (MC) ranging from 18.5-50.0 % wb. Specific heat was measured by the method of mixtures while the thermal conductivity was measured by the line heat source probe method. Thermal diffusivity was then calculated from the experimental results obtained from specific heat, thermal conductivity and bulk density. Bulk density was measured by mass per unit change in volume of the sample. The bulk density was found to be in a range of 1376.2-1130.0 kg m^-3. The bulk density was found to decrease with increasing MC. The specific heat ranged from 1574-2506.8 Jkg^{-1 o}C^-1. The thermal conductivity of the banana varied from 0.249- 0.458Wm^{-1 o}C^-1. The thermal diffusivity ranged from 1.15 х10-7-1.62 х10-7m2s-1. Specific heat, thermal conductivity and thermal diffusivity were found to increase with increasing MC. The effects of MC on all parameters studied were highly significant at (p < 0.05). Regression equations were established which could be used to reasonably estimate the values of bulk density, specific heat, thermal conductivity and thermal diffusivity respectively.

Abstract:

The article presents the results of experimental investigation on the mechanical and two-body abrasive wear behaviour of silicon dioxide (SiO₂) filled glass fabric reinforced epoxy (G-E) composites. Silicon dioxide filled G-E composites containing 5, 7.5 and 10 wt % were prepared by compression moulding technique. The mechanical properties such as tensile strength and modulus were investigated in accordance with ASTM standards. Two-body abrasive wear studies were carried out using pin-on-disc wear tester under multi-pass condition against the water proof silicon carbide abrasive paper. From the experimental investigation, it was found that the presence of SiO₂ filler improved the tensile strength and modulus of the G-E composite. Inclusion of SiO₂ filler reduced the specific wear rate of G-E composite. The results show that in abrasion mode, as the filler loading increases the wear volume loss deceases and increased with increasing abrading distance. The excellent wear resistance was obtained for SiO₂ filled G-E composites. Furthermore, 10 wt % filler loading gave a very low volume loss.

Abstract:

The design, simulation and implementation of VSI fed three phase induction motor drive are presented. The drive system is modeled using the blocks of Simulink. Detailed simulation and implementation of the drive system are given in this paper. Speed response and spectrum analysis are also presented. This drive has advantages like reduced hardware and increased reliability. The experimental results are compared with the simulation results.

Abstract:

The present study define the turbine blade characteristics starting from blade geometry design and continued through an investigation of wake flow generated downstream of blade cascade in a certain boundary conditions. Design of blade geometry was attained by employing of mathematical techniques namely called rapid axial turbine design, RATD. The modified aerodynamic optimization process was used in order to obtain an efficient and reliable optimization blade shape obtained from RATD technique. The wake characteristic was observed by introducing experimental work inside a test rig. This rig consists of rectangular wind tunnel with four blades cascade constructed locally with blade shape adopted from present blade design theory. The wake domain was tested downstream of the blade cascade by aid of five-hole probe for pressure measurements with a pitch angles ranged between -30 and 30 degree in the normal plane direction while the yaw angles was ranged between -30 and 30 degree in the axial plane direction. The total pressure coefficient (Cpt) found to manifest a region of wake propagating starts from the end of wake center at suction surface to almost twice chord length towards downstream direction with a pitch distance equals to half, while at same time another wake region occur at downstream distance of 1.3 of chord length with a 0.75 pitch. These high loss regions represented by appearing of high regions for total pressure loss coefficients vary between 1.7 and 1.9 are caused by secondary flow vortices such as passage vortex which is converted via midspan. It was concluded that the positions of maximum static loss coefficient behavior reveals same level for all downstream axial distance, which results in better performance than Langston model.

Abstract:

The objective of this work is to optimize the direct injection (DI) single cylinder diesel engine with respect to brake power, fuel economy and Emissions through experimental investigations and DOE methods. A single cylinder 5.2 Kw diesel engine was selected for test. Five parameters, Power (P), Static injection pressure (IP), Injection timing (IT), Fuel Fraction (B) and compression ratio (CR) was varied at four levels and the responses break power, fuel economy and emissions were investigated. The optimum n values of the response could be predicted using Signal - Noise ratio(S/N ratio) and optimum combination of control parameters were specified. Results of confirmation tests showed good agreement with predicted quantities. Thus the relationship between the diesel engine parameter and brake power and B.S.F.C. could be understood using design of experiments. The best results for brake specific fuel consumption (BSFC), brake thermal efficiency (BTHE) were observed at increased CR, IP, and IT. The emissions CO, HC were reduced while NOx emissions increase. The results of the study revealed that the combination of a blend of 30% karanja biodiesel (B30), a compression ratio of 17.9, a nozzle opening pressure of 230 bar, injection timing of 27° bTDC and at 70 % Load produces maximum multiple performance of diesel engine with minimum emissions from the engine.