ARPN Journal of Engineering and Applied Sciences                         ISSN 1819-6608
   
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ARPN Journal of Engineering and Applied Sciences                    May 2011 | Vol. 6  No. 5
   
Title:

Regression modeling for strength and toughness evaluation of hybrid fibre reinforced concrete

Author (s):

S. Eswari, P. N. Raghunath and S. Kothandaraman

Abstract:

This paper presents regression equations for evaluating the strength and toughness of hybrid fibre reinforced concrete (HFRC). A total of 102 concrete specimens were tested to study the effect of hybrid fibre reinforcement on the strength and toughness of fibre reinforced concrete. The fibre content dosage Vf ranged from 0.0 to 2.0 percent. Steel and Polyolefin fibres were combined in different proportions and their impact on strength and toughness studied. Addition of 2.0 percent by volume of hooked-end steel fibres increases the modulus of rupture and toughness by about 58.78% and 19.27% respectively, when compared to the plain concrete. When the fibres were used in a hybrid form, the increase in above study parameters was about 81.0% and 31.42% respectively, when compared to the plain concrete. Empirical expressions for predicting the strength and toughness of hybrid fibre reinforced concrete (HFRC) are proposed based on regression analysis. A close agreement has been obtained between the predicted and experimental results.

 
 
 
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Title:

A bootstrap test for equality of mean absolute errors

Author (s):

Naveen Kumar Boiroju, Ramu Yerukala, M.Venugopala Rao and M. Krishna Reddy

Abstract:

In this paper, a bootstrap test procedure for testing of equality of mean absolute errors of two alternative time series models is developed. Applicability of the bootstrap test is explained using two numerical examples and the results compared with the Sign test and Die bold-Mariano Test.

 
 
 
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Title:

A new technique to implement SVC in optimal power flow

Author (s):

Satyendra Singh, Anurag Tripathi and K. S. Verma

Abstract:

The objective of an Optimal Power Flow (OPF) algorithm is to find steady state operating point which minimizes generation cost loss etc. or maximizes social welfare, load ability etc. while maintaining an acceptable system performance in terms of limits on generators’ real and reactive powers, line flow limits, output of various compensating devices etc. Traditionally, classical optimization methods were used to effectively solve OPF. But more recently due to incorporation of FACTS devices and deregulation of a power sector, the traditional concepts and practices of power systems are superimposed by an economic market management. So OPF have become complex. In recent years, Artificial Intelligence (AI) methods have emerged which can solve highly complex OPF problems. The purpose of this paper is to present a study of some optimization techniques used to solve OPF problems and a technique for optimal sizing and implementation of the SVC in optimal power flow. A 26-bus system has been studied to show the effectiveness of the algorithm.

 
 
 
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Title:

Effect of calcium carbonate, sillitin N85 and carbon black fillers on the mechanical and electrical properties of the EPDM

Author (s):

A. A. El-Wakil and A. A. Abd El-Megeed

Abstract:

The improvement of the service life of rubber is dependent on the behavior of the white and black fillers in rubber vulcanizates. The cross linking density of the EPDM vulcanizates, which contain sillitin N85, calcium carbonate, and SRF-black, was measured by using untrasonic technique, pulse echo technique. The aim of this work is to demonstrate the significance of the effect of the fillers on the mechanical and electrical properties of the EPDM. In order to demonstrate the significance of the effect of the fillers, we studied the effect of the aging on the EPDM vulcanizates, which contain sillitin N85, CaCO3, and SRF. The cross linking density was determined by using the ultrasonic technique. It was found, the fillers improves the mechanical and electrical properties of the EPDM vulcanizates. 

 
 
 
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Title:

Some result on common fixed point theorem for a pair of asymptotically non-expansive mappings in generalized s-convex metric space

Author (s):

Deo Brat Ojha, Manish Kumar Mishra, Udayana Katoch and Priyanka Sharma

Abstract:

Let x be a generalized s-convex metric space, and let Q,J be a pair of asymptotically non-expansive mappings. In this paper, we will consider an Ishikawa type iteration process with errors to approximate the unique common fixed point of Q and J.

 
 
 
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Title:

Reduction of NOx emissions in Jatropha seed oil-fueled CI engine

Author (s):

M. K. Duraisamy, T. Balusamy and T. Senthilkumar

Abstract:

Internal combustion engines, which form an essential part of the transportation as well as mechanized agricultural system, have been badly affected by the twin crisis. Many researchers have done a lot of experiment studies in the field of biodiesel to find an alternative to mineral diesel. It has shown that biodiesel-fueled engines produce less carbon monoxide, unburned hydrocarbon, and smoke emissions compared to diesel fuel but higher NOx emissions. Exhaust gas recirculation (EGR) is effective to reduce NOx from diesel engines because it lowers the flame temperature and the oxygen concentration in the combustion chamber. The objective of this work is to investigate the usage of biodiesel from Jatropha Seed Oil and EGR simultaneously in order to reduce the emissions of all regulated pollutants from diesel engine. A fully automated single-cylinder, water-cooled, constant speed direct injection diesel engine was used for experiments. HC, NOx, CO, and smoke of the exhaust gas were measured to estimate the emissions. Various engine performance parameters such as thermal efficiency, and brake specific fuel consumption were calculated from the acquired data. Application of EGR with biodiesel blends resulted in reductions in NOx emissions without any significant penalty in smoke emissions.

 
 
 
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Title:

Evaluation of mechanical properties of Al6061, fly ash and e-glass fiber reinforced hybrid metal matrix composites

Author (s):

Arun Kumar M. B. and R. P. Swamy

Abstract:

Flyash-eglass-Al6061 alloy composites having 2 wt%, 4 wt%, 6wt% and 8wt% of fly ash and 2 wt% and 6wt % of e-glass fiber were fabricated by liquid metallurgy (stir cast) method. The casted composite specimens were machined as per test standards. The specimens were tested to know the common casting defects using ultra-sonic flaw detector testing system. Some of the mechanical properties have been evaluated and compared with Al6061 alloy. Significant improvement in tensile properties, compressive strength and hardness are noticeable as the wt % of the fly ash increases. The microstructures of the composites were studied to know the dispersion of the fly ash and e-glass fiber in matrix. It has been observed that addition of fly ash significantly improves ultimate tensile strength along with compressive strength and hardness properties as compared with that of unreinforced matrix.

 
 
 
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Title:

Performance of the sacrificial galvanic anodes in rehabilitation of marine structure at port Blair, Andaman and Nichobar islands, India

Author (s):

V. Rajendran and R. Murugesan

Abstract:

In recent years, more and more focus has been shifting towards repair and rehabilitation of deficient concrete infrastructures rather than replacement, either in full or replacing the structural members. While carrying out the rehabilitation, one should keep in mind that the methodology should have cost effective strategy and durability. The deterioration caused by the corrosion of reinforcing steel in concrete structures  has been recognized as one of the greatest maintenance challenges being faced by many government agencies and other private owners including the engineering contracting companies in the filed of construction industry today. Technological advances have created a wide range of new product and systems which claim to provide long-lasting protection and serviceability for these structures. However, in order to effectively address the problem it is essential to first understand the cause of the corrosion. The paper describes in detail the philosophy of the corrosion and to evaluate the effect of having anodes installed in the concrete members. The paper also describes in detail investigations conducted on a corrosion damaged jetty approach portion, the repair methodology suggested for the rehabilitation of the structure and executed. The repair methodology proposed included the provision of galvanic anodes. The data presented on the monitoring of the repaired jetty through half cell potential test conducted over a period of one year from the time of completion of the repair to assess the effectiveness of the sacrificial anodes. The investigations have clearly demonstrated that galvanic anodes have proved to be an effective corrosion control technique for reinforced concrete structures.

 
 
 
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Title:

The influence of elastic springs and spring orientation on the draft force during tillage operation

Author (s):

Soeharsono, P. A. S Radite, M. Tineke, H. Wawan and S. Asep

Abstract:

This paper discusses the influence of spring elasticity and spring orientation on the draft force during tillage operation. The experiments were conducted in a soil bin with the following dimensions: 1.2 m in length, 0.3 m in width and 0.4 m in depth. The soil used in this experiment was clay loam soil; the depth of the hardpan in the soil bin was 12 to 15 cm with a penetration resistance of 2.75MPa. The depth of the tillage operation was 14 to 17 cm, and the thickness of the hardpan to be tilled was 7 to 10 cm. The tillage tool was connected to a fixed structure using a semi-elliptical spring. The tillage speeds used were 0.158, 0.212 and 0.265 m/s. Two spring orientations were tested: Rear Spring Treatment (RST) and Front Spring Treatment (FST) orientations. In the RST orientation, the draft force raised the elevation of the tillage tool tip, and the draft force caused the tillage tool tip elevation decrease in the FST orientation. Compared to rigid tine, the average draft force in the FST orientation increased up to 73 %, whereas a draft force reduction was found in the RST orientation.

 
 
 
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Title:

Densification and mechanical properties of sintered powder metallurgy AISI 4340 steel preforms

Author (s):

J. Arivudainambi, G. Ranganath and R. Mariappan

Abstract:

Powder Metallurgy (P/M) manufacturing route has wide industrial applications due to a host of techno-economic advantages. The present investigation has been undertaken to develop and study the characteristics of hot forged AISI 4340 High Strength Low Alloy Steels by using elemental powders through powder metallurgical techniques. The four different aspect ratios namely 0.25, 0.50, 0.75 and 0.90 were prepared by using 1 MN Capacity hydraulic Universal Testing Machine. The green compacts have been sintered at 1100±10°C in hydrogen atmosphere and immediately forged at 1050±10°C by Friction Screw Press. Some of the forged steels were homogenized at 1050±10°C for 1hr, 2hrs and 3hrs in an electrical muffle furnace. The forged and homogenized AISI 4340 steels were subjected in to densification studies and mechanical properties evaluation. Lower aspect ratio preforms such as 0.25 and 0.50 exhibited better densification properties. Two hours homogenized forged steels exhibits better mechanical properties.

 
 
 
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Title:

Performance evaluation of bamboo (Oxytenanthera abyssinica) low-cost micro irrigation lateral system

Author (s):

B. G. Umara, I. Audu and A. U. Bashir

Abstract:

The objective of this study was to develop construction techniques and determine the application uniformities of a bamboo low-cost micro irrigation lateral system. Fresh bamboo stalks were sorted, dried and bored. The system’s three 4 m long laterals made of bamboo tube with an average internal diameter of 1.7 mm were connected to a bamboo mainline pipe with an average diameter of 3 mm which receives water from the plastic reservoir. The mean flow rate of 5.91 litres per hour through about 1.9 mm diameter emitters falls within the acceptable discharge range for micro irrigation systems. A systems performance assessment based on standards for micro - irrigation systems was carried out. Average discharge variations, coefficient of manufacturing variation, emission uniformity, Christiansen coefficient of uniformity and distribution efficiency were 30%, 9.8%, 73%, 92% and 88%  respectively from the 1.9 mm emitter orifice fall within the recommended values for micro-irrigation systems. Method of orificing and cleansing of emitters should be improved upon, so as to reduce the flow rate variations in the emitters.

 
 
 
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Title:

Integration of HRV, WT and neural networks for ECG arrhythmias classification

Author (s):

A. Dallali, A. Kachouri and M. Samet

Abstract:

The classification of the electrocardiogram registration (ECG) into different pathologies disease devises is a complex pattern recognition task. The registered signal can be decomposed into three components, QRS complex, P and T waves. The QRS complex represent the reference for the other ECG parameters; the width and amplitude QRS have more important to identify the ECG pathologies. The statistical analysis of the ECG indicate that they differ significantly between normal and abnormal heart rhythm, then, it can be useful in detection of ECG arrhythmia. The traditional methods of diagnosis and classification present some inconvenient; seen that the precision of credit note one diagnosis exact depends on the cardiologist experience and the rate of concentration. Due to the high mortality rate of heart diseases, early detection and precise discrimination of ECG arrhythmia is essential for the treatment of patients. During the recording of ECG signal, different form of noises can be superimposed in the useful signal. The pre-treatment of ECG imposes the suppression of these perturbation signals, three methods for the noisily of signals are used; the time frequency domain, by Wavelet Transform (WT). The features are extracted from wavelet decomposition of ECG signal intensity. The inclusion of Artificial Neural Network (ANN) based on feed forward back propagation with momentum, in the diagnostic and classification of ECG pathologies have very important yield [1, 2]. The four parameters considered for ECG arrhythmia classification are the interval RR, the QRS width, the QRS amplitude, and the frequency of appears QRS. Due to the large amount of input data, needed to the classifier, the parameters are grouped in batches introduced to artificial neural network. The classification accuracy of the ANNs introduced classifier up to 90.5% was achieved, and a 99.5% of sensitivity.

 
 
 
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Title:

Nonlinear damped oscillations: A case study of dysfunctions in smooth pursuit eye tracking-I

Author (s):

C. V. Pavankumar and N. Ch. Pattabhi Ramacharyulu

Abstract:

This paper presents a simple deterministic model of dysfunctions of eye- tracking. The model is formulated as a second order nonlinear ordinary differential equation, incorporating non Hookesien cubic restoring force. The equation is solved by employing a perturbation technique with the nonlinear restoring force coefficient as the perturbation parameter. Numerical estimation of the displacement is computed for a wide spectrum of the eye dysfunction. The significance of the effects of time, the frequency and amplitude of the exiting force on displacement has been discussed by adopting ANOVA technique. The critical levels of time, amplitude and frequency have also been noted to be at 5.59sec, 5.125 and 0.5798, respectively corresponding to 0.05 level of significance.

 
 
 
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Title:

Behavior of ultra high performance concrete structures

Author (s):

Adel A. Al-Azzawi, Ahmed Sultan Ali and Husam K. Risan

Abstract:

A study has been made through this investigation to understand the behavior of UHPC members with steel fibers by using two approaches: experimental investigation of concrete mixes and simulation of the problem studied by other researchers using finite elements. Experimental investigation is carried out to obtain the mechanical properties for two types of UHPC mixes, namely, the type of pozzolanic admixture (Silica Fume and High Reactivity Metakaolin) in addition to use three different values of steel fibers volume fraction (1%, 1.5% and 2%). The finite element method through the ANSYS computer program is used. The eight node brick element is used to model the UHPC beams with embedded steel fibers. The stress-strain curve in compression for the UHPC with steel fibers is simulated by a nonlinear elasto-plastic model which is terminated at the onset the crushing. In tension, a smeared crack model with fix orthogonal cracks has been used. The experimental data obtained from other researchers is compared with the finite element solution and good agreement between the results is obtained. Parametric studies are carried out to investigate the effects of type of pozzolanic admixture, volume fraction of steel fibers and other solution parameters. Higher values of compressive strength have been achieved using UHPC mixes with Silica Fume in comparison with UHPC mix with High Reactivity Metakaolin.  

 
 
 
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