Load-Settlement Response of Square Footing on Geogrid Reinforced Layered Granular Beds

Experimental studies were carried out to obtain the load-settlement response of a model square footing resting on unreinforced and reinforced granular beds. The response was obtained for two cases: (a) geogrid-reinforced sand layer, and (b) geogrid-reinforced layered system consisting of aggregate layer overlying a sand layer. The parameters considered in the experimental study include the thickness of the aggregate layer, the depth of geogrid reinforcement placed in sand layer and in aggregate layer, width of the reinforcement, and relative density of bed. Plate vibrator was used to compact uniform sand beds to relative densities equal to 50 % and 70 % inside large-size test chamber of dimensions equal to 1 m × 1 m × 1 m (in length, in width, and in depth). Load was applied on square footing using a 100 kN capacity actuator in displacement-controlled mode, and the improvement in the load carrying capacity of the footing resting on reinforced sand layer and layered system was quantified in terms of load improvement factors. In addition, the optimum embedment depth and width of reinforcements were proposed for various cases considered in the study. The optimum depth of reinforcement for the case of aggregate layer overlying sand layer decreased to 0.30 times the width of the footing from 0.45 times the width of the footing for sand only case

Fully Invariant and Characteristic Interval-Valued Intuitionistic Fuzzy Dual Ideals of BF-algebras

The notion of interval-valued intuitionistic fuzzy sets was first introduced by Atanassov and Gargov as a generalization of both interval-valued fuzzy sets and intuitionistic fuzzy sets. Satyanarayana et. al., applied the concept of interval-valued intuitionistic fuzzy ideals and interval-valued intuitionistic fuzzy dual ideals to BF-algebras. In this paper, we introduce the notion of fully invariant and characteristic interval-valued intuitionistic fuzzy dual ideals of BF-algebras and investigate some of its properties

Evaluation of Contact Stresses in Bearings Made of Al – Beryl Metal Matrix Composites by Finite Element Method

AbstractIn the present investigation, interference fitted assemblies were analyzed using finite element method to evaluate contact stresses. The main objective of this research work is to develop metal matrix composite of commercially available pure aluminum reinforced with different weight percentage of Beryl to attain a most desirable property combination for bearings. A detailed analysis on the effect of bearing material on contact stresses was undertaken. The work covers the analysis based on Hertzian contact stresses. An appropriate finite element model was developed to analyze the pattern of contact stresses in the interference assemblies. Ansys workbench was used as a tool to construct the model and to perform analysis. The model was simulated by applying a pressure of 100MPa and at different speeds of the shaft. A comparative study on the effect of bearing materials such as bronze, Al-SiC and Al-Beryl MMCs on contact stresses were clearly demonstrated. It has been found that the contact stresses in the bearings made of Al-Beryl metal matrix composite was in the range of 4678.7 to 4680Pa at different speeds which was very much less when compared to the bronze and Al- SiC MMC. The results clearly demonstrated Al-Beryl can be used as one of the most suitable materials for fabricating bushes

Predictive maintenance and fault diagnosis of hydraulic gear coupling of a boiler feed pump unit

Increasing demand for reliability and performance of today’s most complex machines, and maintaining high productivity without sacrificing product quality have made it imperative for maintenance engineers to devise newer strategies in maintenance of plant and machinery. One of such strategies is condition monitoring, which has emerged as one of the most powerful technology in maintenance engineering. Condition monitoring and diagnostic engineering is a novel concept which enables us to detect in advance any incipient failure with ease and confidence in any part of a dynamic system before such failure trigger – off various types of failure mechanisms, which in turn may render the whole system uneconomical, unreliable, unhealthy, unsafe and even lethal. The present work highlights an experimental investigation to monitor the vibration behavior of hydraulic gear coupling, which is a part of Boiler Feed Pump train of a large utility Thermal Power Plant.  The coupling is supported by 4 Bearings. Tri-axial measurements are made at the bearing supports for 12 months. Displacement and Velocity are measured along Horizontal, Vertical and Axial directions. The experimental data is plotted on Time domain for graphical analysis to ease viewing of vibration signals. Based on the experimental data, faults are diagnosed using ISO – 2372 standards and causes are predicted. It is observed that the front and rear bearings of Input and output shafts of coupling are experiencing excess vibration. The work is concluded by suggesting remedial measures to ensure vibration intensity, at the said points, within the safe limits.&nbsp

Optimized Coefficients of Interpolation Filter To Adapt Statistical Property of Each Image

Spatial transform has assumed an essential part in most picture and video coding routines. Wavelet change has numerous points of interest, for example, multi-determination representation, great vitality compaction and de-correlation. We propose another weighted versatile lifting (WAL)- based wavelet change that is intended to take care of the issues existing in the past versatile directional lifting (ADL) approach. The proposed methodology utilizes the weighted capacity to ensure that the prediction and update stages are predictable, the directional addition to enhance the introduction property of added image, and adaptive interpolation filter to adjust to statistical property of each image

SIMULATION AND PERFORMANCE ANALYSIS OF CNG FUELED HCCI ENGINE

ABSTRACT 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

Expectation of forward-backward rapidity correlations in p+pp+p collisions at the LHC energies

Forward-backward correlation strength ($b$) as a function of pesudorapidity intervals for experimental data from $p+\bar{p}$ non-singly diffractive collisions are compared to PYTHIA and PHOJET model calculations. The correlations are discussed as a function of rapidity window ($\Delta \eta$) symmetric about the central rapidity as well as rapidity window separated by a gap ($\eta_{gap}$) between forward and backward regions. While the correlations are observed to be independent of $\Delta \eta$, it is found to decrease with increase in $\eta_{gap}$. This reflects the role of short range correlations and justifies the use of $\eta_{gap}$ to obtain the accurate information about the physics of interest, the long range correlations. The experimental $b$ value shows a linear dependence on $\ln \sqrt{s}$ with the maximum value of unity being reached at $\sqrt{s}$ = 16 TeV, beyond the top LHC energy. However calculations from the PYTHIA and PHOJET models indicate a deviation from linear dependence on $\ln \sqrt{s}$ and saturation in the $b$ values being reached beyond $\sqrt{s}$ = 1.8 TeV. Such a saturation in correlation values could have interesting physical interpretations related to clan structures in particle production. Strong forward-backward correlations are associated with cluster production in the collisions. The average number of charged particles to which the clusters fragments, called the cluster size, are found to also increase linearly with $\ln \sqrt{s}$ for both data and the models studied. The rate of increase in cluster size vs. $\ln \sqrt{s}$ from models studied are larger compared to those from the data and higher for PHOJET compared to PYTHIA. Our study indicates that the forward-backward measurements will provide a clear distinguishing observable for the models studied at LHC energies.Comment: 15 pages, 14 Figures, accepted for publication in International Journal of Modern Physics

Reflective Coating on Fibrous Insulation for Reduced Heat Transfer

Radiative heat transfer through fibrous insulation used in thermal protection systems (TPS) is significant at high temperatures (1200 C). Decreasing the radiative heat transfer through the fibrous insulation can thus have a major impact on the insulating ability of the TPS. Reflective coatings applied directly to the individual fibers in fibrous insulation should decrease the radiative heat transfer leading to an insulation with decreased effective thermal conductivity. Coatings with high infrared reflectance have been developed using sol-gel techniques. Using this technique, uniform coatings can be applied to fibrous insulation without an appreciable increase in insulation weight or density. Scanning electron microscopy, Fourier Transform infrared spectroscopy, and ellipsometry have been performed to evaluate coating performance

HYDROGEN FUELLED IC ENGINE – AN OVERVIEW

Hydrogen as a fuel in Internal Combustion engines is a solution for the near future to realize zero CO2 emissions for traffic applications. The hydrogen fuelled IC engine is ready for that. The storage and production of hydrogen, and to build the necessary infrastructure, are the real shortcomings in the general use of hydrogen in IC engines. This paper gives an overview of the development of hydrogen fuelled IC engines by the most important car manufactures (Ford, BMW etc.). This overview indicates the evolution in the development of hydrogen fuelled engines (different generation of engines). This evolution is also made at Ghent University. Ghent University has been working for nearly 15 years on the development and optimization of hydrogen engines. Several test rigs are in function (all with electronic control management systems and sequential multi-point injection)

A low power IoT network for smart agriculture

Traditional agriculture is transforming into smart agriculture due to the prominence of the Internet of Things (IoT). Low-cost and low-power are the key factors to make any IoT network useful and acceptable to the farmers. In this paper, we have proposed a low-power, low-cost IoT network for smart agriculture. For monitoring the soil moisture content, we have used an in-house developed sensor. In the proposed network, the IITH mote is used as a sink and sensor node which provides low-power communication. We have evaluated our network with state of the art networks, proposed for agriculture monitoring. Power and cost are the two metrics used for evaluation of these networks. Results show that the proposed network consumes less power and has prolonged lifetime in the agriculture field