Freddy-Humberto Escobar, Claudia-Marcela Corredor, Beatriz-Elena Gomez, Jose-Humberto Cantillo and Larry-Alberto Prent

A well that penetrates the producing the producing interval with a slant angle, y is called an inclined or slant well. If the well does not penetrate the entire formation thickness of the producing strata, it is called a partially penetrating or limited-entry well. For such cases, the slant angle, penetration length and penetration ratio significantly influence the characteristics of the pressure-transient responses. It is relevant the role of the ellipsoidal flow regime displayed at early time - before radial flow - which we recognized as a straight line exhibiting a -0.135 slope on the pressure derivative curve. Hence, this paper deals with the characterization of such flow regime and a methodology, using the pressure derivative, is introduced so the vertical and effective permeability is calculated. The proposed methodology was successfully applied to synthetic test data.

Internal crack assessment on concrete structures by scanning image analysis

A. Zacoeb, Y. Ito and K. Ishibashi

Demand for the development of non destructive test (NDT) techniques have improved with the growing concern about the deteriorating condition of concrete structures. Efficient and accurate imaging techniques are needed for a reliable evaluation of safety and serviceability of concrete structures. Although, presently, imaging is routinely used in various fields, implementation of these technologies in NDT of civil engineering systems, especially of concrete structures, offers many challenges and requires additional development due to the composite nature of the concrete material and the complexities of reinforced concrete systems. In this paper, the feasibility of visual observation device that developed with small inspection borehole for investigating internal crack in concrete structure by scanning technique is presented. Special considerations regarding the applicability and accuracy of these techniques for the condition assessment of concrete structures are discussed, and examples of field application are given.

Image enhancement through contrast improvement using parameterized gradient intercept model

I. Suneetha and T.Venkateswarlu

Quality of the image is not satisfactory in many cases to extract the useful information. Image enhancement process gives better visual quality either by increasing the contrast or suppressing the noise. As all enhancement techniques are application oriented, it is necessary to find a method which needs simple operations with effective enhancement and does not require complex operations like logarithmic, exponential, Probability Density Function. This paper proposes a method for image enhancement through contrast improvement using a Parameterized Gradient Intercept Model in spatial domain. The proposed method provides good results subjectively as well as objectively for both gray scale and true color images. The proposed method is useful for interactive image processing applications as it has a family of possible transformations for various enhancement levels.

Simulation and performance analysis of CNG fueled HCCI engine

P. M. Diaz and B. Durga Prasad

Compressed Natural Gas (CNG) is a difficult fuel to use in a Homogenous Charge Compression Ignition (HCCI) engine because of high octane number, high auto-ignition temperature, and rapid heat release. These properties force CNG HCCI engines to use extreme levels of intake heating. The Homogeneous Charge Compression Ignition concept has the potential to meet the need for a high efficiency and low emission engine. Fluent is one of the promising operating tools in the computational fluid dynamics. In the present study the Computational Fluid dynamics (CFD) code FLUENT is used to model complex combustion phenomenon in homogeneous charge compression Ignition engine. The variation of various properties like the peak cylinder pressure, peak cylinder temperature at various crank angles, at different relative air fuel mixture inlet temperatures and with hemi spherical combustion chamber and toroidal bowl has been studied. It was found that heated inlet air fuel mixture enhance combustion, peak cylinder pressure, peak cylinder temperature and change peak pressure timing.

Bearing characteristic of foundation on cement admixed clay layer under elevated temperature

Anuchit Uchaipichat

Abstract:

This paper presents the simulation results of bearing capacity characteristic of foundation on cement admixed clay layer under elevated temperature using the experimental data reported in literature. The simulation results show a decrease in bearing capacity of foundation on cement admixed clay layer with temperature. At higher cement content, the effect of temperature is more influent on the bearing capacity. Furthermore, the safety factor increases with increasing cement content for small value of cement content. With increasing cement content greater than 5%, the safety factor decreases with increasing cement content.

Numerical solution for a radial composite reservoir model with a no-Newtonian Newtonian interface

Freddy Humberto Escobar, Javier Andrés Martínez and Luis Fernando Bonilla

Abstract:

Normally, some heavy crude oils and several well treatment fluids possess a non-Newtonian nature. This nature makes the fluid behavior to behave differently than a Newtonian one. Therefore, transient pressure analysis, for instance, will have different considerations. Moreover, if for any reason, a non-Newtonian fluid is injected into a reservoir which contains a Newtonian crude oil; two different fluid flow zones will be well established and defined. Therefore, two different diffusivity equations are governing the fluid flow through the porous medium. The simultaneous solution to that problem may be a numerical challenge if not dealt appropriately. In this work we present the numerical solution for a power-law Non-Newtonian diffusivity model coupled with a Newtonian diffusivity model by the finite-difference approximation. Results were successfully compared to those reported in the literature without reporting the detail solution.

Investigation of SFRC corbel performance using a developed nine-noded lagrangian elements

James H. Haido

In present work, novel steel fiber reinforced concrete (SFRC) behavior nonlinearities were proposed depending on various experimental studies outcomes. Nine-noded Lagrangian finite elements procedure was developed using the proposed material behavior nonlinear relationships to investigate the performance of SFRC corbel. The stiffness matrix was determined in many ways dependent on the initial and tangential stiffness values. The results were given in terms of maximum deflections and crack formation of the corbel. Good agreement was observed between present numerical analysis results and that for other related studies. The average ratio between current numerical outcomes and other experimental results is about 0.89655 in terms of maximum displacements and ultimate loads.

Sewage water irrigation effects on ground water quality in Semel area (Iraq)

Ma’an H. Sheet

Abstract:

Pressure and pressure derivative analysis for pseudoplastic fluids in vertical fractured wells

Freddy Humberto Escobar, Diego Fernando Bonilla and Yuslly Yenith Cicery

Abstract:

Petroleum engineers often deal with Non-Newtonian fluids in many activities of the oil industry. Some of these fluids are used as fracturing, EOR and drilling mud fluids. If one of these fluids is used to fracture a well and a post-fracture test is run, afterwards, the interpretation cannot be conducted with the conventional models. A pseudoplastic model has to be used. The oil literature presents only one work on well test analysis for fractured wells with non-Newtonian fluids. The application was specific for fall-off testing and the interpretation for determination of the half-fractured length is conducted using both the conventional straight-line method and type-curve matching. However, applications of the pressure derivative for this type of systems have not been performed yet. This paper presents a methodology using the pressure and pressure derivative log-log plot for interpretation of pressure transient tests in infinite-conductivity vertically fractured wells with a pseudoplastic fluid. The interpretation was extended to estimate the half-fracture length and the well drainage area. It was successfully tested on field and synthetic data.

M L estimation of the reliability measures of a two unit system in the presence of two kinds of CCS failures

B. R. Sreedhar, G. Y. Sagar, K. Pushpanjali and Y. R. Reddy

Abstract:

This paper propose the Maximum likelihood estimation (M L Estimation) approach for the reliability measures such as Reliability function [R_s (t)] and Mean time between failures [MTBF] of two component non-identical system. The system is assumed to be under the influence of Lethal and non-lethal Common Cause Shock failures. The estimates are proposed for the above said reliability indices of the system both for Series and Parallel system. Numerical illustration is also provided to justify the use of M L estimation procedure in this case.

Abstract:

One of the most common distresses on Lagos (the economic nerves centre of Nigeria) and Ibadan the largest city in West Africa Expressway pavement is surface rutting. Rutting makes the road surface uneven, patchy and bumpy and subsequently affects the handling of vehicles which can lead to safety problems. The ability to predict the amount and growth of rutting in flexible pavements is an important aspect of pavement design. This paper presents the results of a research aimed at developing reliable and time - dependent Artificial Neural Network (ANN) based rut depth prediction model for Lagos - Ibadan Expressway. The model incorporate relevant variables such as pavement distresses, pavement layer thickness, pavement roughness, cumulative equivalent single axle load, sub grade California Bearing Ratio (CBR) and overlay asphalt concrete characteristics. The results showed that the forecasting accuracy of the 11-24-1 architecture is high compared with other tested architecture in terms of both average absolute error (AAE) and root mean square error (RMSE). The usage of the model will allow the road agencies to obtain reliable and accurate predictions of the future rut depth of the flexible pavements based on the given input variables.

Abstract:

Suddenly expanded flow with active controls in the form of micro jets has been investigated experimentally, laying emphasis on the effectiveness of Micro jets on the base pressure and enlarged duct pressure field. Air injection at four locations at the base, symmetric to the nozzle axis is used as the active control. The jet Mach numbers of the present studies are 1.87, 2.2 and 2.58. The area ratio of present study is 6.25. The length-to-diameter ratio of the suddenly expanded duct and the Nozzle Pressure Ratio (NPR) are varied from 10 to 1 and 3 to 11. In addition to base pressure, wall pressure field along the duct was also studied. It is found that the active control in the form of blowing through small orifices (micro jets) are effective in controlling the base pressure field. Micro jets do not augment the flow field in the duct. As high as 55 percent increase in base pressure was achieved for certain combination of parameters of the present study.

A prey-predator model with an alternative food for the predator and optimal harvesting of the predator

K. Madhusudhan Reddy and K. Lakshmi Narayan

Abstract:

The present paper deals with a prey - predator model comprising an alternative food for the predator in addition to the prey, and the predator is harvested under optimal conditions. The model is characterized by a pair of first order non-linear ordinary differential equations. All the four equilibrium points of the model are identified and the criteria for the stability are discussed. The possibility of existence of bioeconomic equilibrium is discussed. The optimal harvest policy is studied with the help of Pontryagin’s maximum principle [17]. Finally, some numerical examples are discussed.

Investigation the dynamic stresses of vibration in outer race of low speed ball bearing

Thaker Salih Dawood

Abstract:

The race ring in vehicle are subjected to sever load acting between the rolling elements and raceways in rolling bearings which develop only small area of contact between the mating members. Large level of stresses is developed on the surface of the rolling elements and raceways. Consequently, although the elemental loading may only be moderate, stresses induced on the surfaces of the rolling elements and raceways are usually large. The determination of deformation and stress distributions due to both static and dynamic loading is essential in the design stage of the raceways. Finite element model of a stress analysis of the ball bearing has been built considering the race ring as a plane stress problem and choosing the 8=node isentropic quadrilateral element. A computer package Ansys/5.4 for both static and dynamic analysis. The more damping ratio used, the more stabilizing of the stresses with respect to time.

Electrical load forecasting using genetic algorithm based back- propagation method

Abstract:

Forecasting is the way of knowing the future value based on some past records. In electrical power systems, there is a great need for accurate forecasting of the future load and energy requirements. Accurate load forecast provides system dispatchers with timely information to operate the system economically and reliably. It is also necessary because availability of electricity is one of the most important factors for industrial development, especially for a developing country like India. It is required to be careful that the energy forecast is neither too conservative nor too optimistic. Artificial Intelligence techniques have shown promising results in many systems. Recent progress in the applications of Artificial Neural Networks (ANN) technology to power systems in the areas of forecasting has made it possible to use this technology to overcome the limitations of the other methods used for electrical load forecasting. In this work, the GA-BPN model is used for extracting the best weight matrices for different layers of BPN thus forecasting the future power demand more accurately. For this reason, this work introduces evolution of connection weights in ANN using GA as means of improving adaptability of the forecasting.

Abstract:

Wavelet mathematical transformation and heart sound signal processing have recently been attracting a significant amount of attention in the research community. Why is this new priority being given to improved approach to heart sound signal analysis for accurate pattern recognition using the wavelet transform technique? This article provides an overview of this emerging field of digital bio-signal processing, clarifying how wavelet transformation is superior to other signal processing techniques such as Fast Fourier Transform (FFT) and Short Time Fourier Transform (STFT). The article presents an overview of mathematical and theoretical background for Discrete Wavelet Transform (DWT). It discusses the application of a new DWT algorithm to the analysis and characterisation of heart sounds for diagnostic purpose and charts a course for future research direction in the field of knowledge discovery in databases (KDD).

A proficient system for preventing and acknowledging about the drunken drive by analysing the neuronal - activitiy of the brain

Paulchamy. B and Ila Vennila

Abstract:

As it is regardless to say, majority of accidents occur due to drunken driving. Driving while intoxicated (DWI) (drunken driving, which means operating under the influence of alcohol, drinking and driving, impaired driving) is the act of driving a motor vehicle with blood levels of alcohol in excess of a legal limit. Though drunken driving is considered to be a criminal offense in most countries, it still remains to be a serious, unavoidable problem. Therefore, a highly efficient system that provides early prevention of drunken drive to protect the public from drunken drive male facts is the current need to society. In this paper, we intend to propose the designed mechanical system that prevents drunken drive and its subsequent catastrophes by monitoring the EEG of the driver. The power of the EEG signal in frontal region(alpha waves) decreases with the increase in the amount of alcohol intake, and the power of the EEG signal in central, occipital region (delta, beta) increases. Therefore, in our paper, we make use of threshold values of alpha, beta and theta waves to differentiate EEG of alcoholic from non-alcoholic. The continuous monitoring the EEG of the driver makes our system highly reliable to prevent drunken drive accidents. Further, in our proposed system, we make use of special indicators called prevention indicator to avoid inconvenience to other drivers and prevent the accidents due to collision of vehicles. Once any evidence of drunk driving is present, SMS which contains the current location of the driver by means of GPS is sent via a GSM module to the police control room. Thus our exemplary system emerges to be a highly efficient and cost effective solution to prevent drunken drive accidents.

Potential capability of corn cob residue for small power generation in rural Nigeria

Mohammed Yekini Suberu, Ahmad Safawi Mokhtar, Nouruddeen Bashir

Abstract:

The ongoing global decarbonization strategies has paved ways for mixed power generation options involving both conventional and non-conventional source of energy which is aiming at the simultaneous interest of lowering the price per unit of energy produced and sustaining healthy environmental requirements. However, future energy supply structures is expected to be dominated by renewable energy systems distributed generation while the reserves of fossil-based energy resources continue to decline on daily basis. Possible conversion technologies for electrical power generation utilizing the bio-residue were also discussed. Therefore, this article seeks to investigate the potential opportunity of small power generation from biomass corn cob residue in Nigeria. A mathematically developed method was employed for evaluating the potential of the residue for power generation. Data from the United Nations Food and Agricultural Organization (FAO) statistics was used for the analysis and concentrated body of literature back-up was also exploited for the analysis. The observation of data was carried-out from 1996 to 2010, though the general result signifies a fluctuating potential. Summarily, the outcome of the study indicated that close to 3000MW electrical power is possible with availability of 70% of the residue in 2010. The study was concluded with brief description on prospect for implementation strategies of rural bioelectricity project.

Abstract:

In this research, a hybrid model has been developed for municipal water demand forecasting based on the wavelet and artificial neural network methods. The developed model combines the discrete wavelet transforms (DWT) with multilayer perceptron neural network (MLP) called Wavelet-ANN. In order to assess the credibility of developed model results, the model was run over the available data which include the time series of daily and monthly municipal water consumption for fourteen years (1/1/1992 - 31/12/2004) of Tampa city, USA. In the developed model, the Daubechies wavelet function with different orders and levels of resolution were used in the decomposing process of time series. The approximation and each detail of the decomposed water consumption time series were modeled using the MLP neural network. It is quite clear from the results obtained from both daily and monthly forecasting models for municipal water consumption time series considered in this research that the hybrid Wavelet-ANN approach provides accurate daily and monthly forecasts as measured using a validation period of 5, 10 and 15 for daily data and 24 months for monthly data, recording MAPE values (≤ 1.029%) and R2 values (≥ 0.967).

Improvement in the compressive strength and flexural strength of dental composite

Umesh V. Hambire, V. K. Tripathi and Atmaram G. Mapari

Abstract: