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Development of Fly Ash based Geopolymer behaviour of Fly Cement
Get PDFGeopolymer is a novel binding material produced from the reaction of fly ash with an alkaline activator liquid; ensure durability and environmental sustainability and is emerging greener alternative to Ordinary Portland cement in the construction field. In this research, the influence of various parameters on the consistency and setting times of low-calcium fly ash-based geopolymer cement under varied heat curing temperature were investigated. Systematic trials were carried to optimise the normal consistency and setting times over a number of parameters. The consistency of the geopolymer cement does not show any variation when mixed with different combinations of alkaline activator solution; whereas the setting times were observed to be dependent on the concentration of NaOH solution, ratio of alkaline activator liquid and variation in temperature. The test results revealed that the normal consistency of the fly ash-based geopolymer paste is found to be at 28% of alkaline activator solution for all the selected mixtures. Wherein, increase in concentration of NaOH solution increases setting times; increase in alkaline liquid ratio decreases setting times up to certain limits viz; increase in alkaline liquid ratio from 1.5 to 2.0, decreases setting times; further increase in alkaline liquid ratio from 2.0 to 2.5, increases setting times. The setting times were observed as decreased when the alkaline liquid ratio increased from to 2.5 to 3.0
Design of RF Low Noise Amplifier at 2GHz in 0.18μm Technology
Get PDFA 2GHz Low Noise Amplifier (LNA) has been implemented in Cadence Spectre RF tool on UMC 0.18μm technology and is designed using a modified Cascode topology to work under reduced power supply. The input and output matching network is matched to 50Ω. After simulation it is found that at resonance frequency of 2GHz, the forward gain is 18.22dB and reverse isolation is -40.86dB
A Review of Contemporary Data Quality Issues in Data Warehouse ETL Environment
Get PDFIn today’s scenario, Extraction–transformation– loading (ETL) tools have become important pieces of software responsible for integrating heterogeneous information from several sources. The task of carrying out the ETL process is potentially a complex, hard and time consuming. Organisations now –a-days are concerned about vast qualities of data. The data quality is concerned with technical issues in data warehouse environment. Research in last few decades has laid more stress on data quality issues in a data warehouse ETL process. The data quality can be ensured cleaning the data prior to loading the data into a warehouse. Since the data is collected from various sources, it comes in various formats. The standardization of formats and cleaning such data becomes the need of clean data warehouse environment. Data quality attributes like accuracy, correctness, consistency, timeliness are required for a Knowledge discovery process. The present state -of –the- art purpose of the research work is to deal on data quality issues at all the aforementioned stages of data warehousing 1) Data sources, 2) Data integration 3) Data staging, 4) Data warehouse modelling and schematic design and to formulate descriptive classification of these causes. The discovered knowledge is used to repair the data deficiencies. This work proposes a framework for quality of extraction transformation and loading of data into a warehouse
Coal characterisation and design for fossil fuel fired boiler in thermal power plants.
Get PDFCoal is a highly heterogeneous in nature and requires several analytical techniques for its characterization so as to accurately predict its behavior during conversion processes such as combustion, gasification or liquefaction. The goal of utilizing the available large quantities of indigenous coal alone with reducing emissions is increasing the efficiency of power plants by utilizing steam conditions. The performance correlations based on bulk property analysis of coal adequately impact coal quality on conversion efficiencies and plant performance. Thermo mechanical analysis , an advanced bulk analytical technique provides detailed thermal behavior of ash relevant to power plant operations. The decrease in easily worked deposits , together with the decline in the availability of the better quality coals has resulted in a need for the development of blending techniques. Blending is now extensively practiced in the preparation of coals which involve blending of several different classes and / or grades of coals to produce blends which on carbonization will yield coke. Coal petrology is the study of organic materials which make up coal .The object of study is to identify in terms of reactive capabilities , each of the organic materials making up coal and an attempt to relate the reactive capabilities with the industrial applications of coal. Various tests are being designed to investigate the feasibility of Indian Coals in pulverized coal boilers
Concrete Mix Design Using Artificial Neural Network
Get PDFConcrete mix design is a process based on sound technical principles for proportioning of ingredients in right quantities. This paper demonstrates the applicability of Artificial Neural Networks (ANN) Model for approximate proportioning of concrete mixes. For ANN a trained back propagation neural network is integrated in the model to learn experimental data pertaining to predict 7, 14 and 28-day compressive strength which have been loaded into a model, containing 55 concrete mixtures. The ANN model proposed is based on 5 input parameters such as cement, sand, coarse aggregate, and water and fineness modulus. The proposed concrete mix proportion design is expected to reduce the number of trials in laboratory as well as field, saves cost of material as well as labor and also saves time as it provides higher accuracy. The concrete designed is expected to have higher durability and hence is economical
Image Compression using an efficient hybrid algorithm
Get PDFThis research paper proposes a method for the compression of medical images using an efficient hybrid algorithm. The objective of this hybrid (DWT,DCT and Huffman quantization) scheme is to calculate the compression ratio, peak signal to noise ratio and mean square error by changing the DWT level and Huffman quantization factor. The goal is to achieve higher compression ratio by applying different compression thresholds for the wavelet coefficient of each DWT band and then DCT with varying Huffman quantization factor while preserving the quality of reconstructed image. First DWT and DCT is applied on individual components RGB. After applying this image is quantized using Huffman quantization to calculate probability index for each unique quantity so as to find out the unique binary code for each unique symbol for their encoding
BER Performance in Digital Video Broadcasting-Terrestrial for Inner and outer Interleaving Using 64 QAM
Get PDFDigital video broadcasting-terrestrial (DVB-T) was developed by the DVB Project that was first broadcast in the UK in 1997. The compressed digital audio, video and other data in Moving Picture Expert Group (MPEG) transport stream, using orthogonal frequency-division multiplexing (OFDM) modulation is transmitted by this system. In order to analyze how an MPEG transport stream at the input of a DVB-T modulator is turned into a DVB-T signal, the channel coding and modulation technique must be considered. DVB-T offers three different modulation schemes (QPSK, 16QAM, 64QAM). This paper analyzes the performance of the system for the stationary reception. The aim was to implement all the functional blocks as specified in the DVB-T specification and analyze the BER performance of the system. Thus, this paper deals with a MATLAB application being developed to simulate DVB-T system for selected QAM. This work deals with the MATLAB code to establish a system level simulation environment and use this system simulation model to evaluate the system performance hence provide the result in evaluating the performance of DVB-T with 64QAM. This system is able to measure and analyze the performance of bit error rate (BER) versus energy per bit to noise power spectral density ratio (Eb/No) for 64 QAM
Application of Silica Fume and Nanosilica in Cement and Concrete - A Review
Get PDFThis paper reviews the recent developments and present state of the application of silica fume (micro-silica) and nano-silica for sustainable development of concrete industry. This would save not only the natural resources and energy but also protect the environment with the reduction of waste material. Limited work is done on use of nano-silica and microsilica in paste, mortar and concrete and whatever work is available is highly contradictory about their influence on mechanical strength development and durability properties. Various literatures have been reviewed to understand the influence of micro and nano-silica on fresh, hardened and microstructural properties of paste, cement mortar and concrete. Taking advantage of nanostructure and microstructure characterization tools and materials, the simultaneous and also separate optimal use of micro-silica and nano-silica will create a new concrete mixture that will result in long lasting concrete structures in the future
Photoluminescence and Photo-catalytic Activity of Synthesized Nanocrystals
Get PDFIntrinsic and extrinsic semiconductor nanostructures have attracted great attention due to their size tunable photo-physical and photo-chemical properties. In the present paper, polyvinyl pyrrolidone (PVP) capped Zn1-xEuxS (0.00001≤x≤0.1)nanocrystals have been synthesized by means of a facile chemical synthesis method. Crystallography and morphology of synthesized materials have been deliberated using X-ray diffraction (XRD) and transmission electron microscope (TEM), respectively. Diffraction and electron micrograph studies reveal that the synthesized materials are zinc blende nanocrystals having average particle size ~3nm. Elemental and compositional analyses of the nanocrystals have been done using energy dispersive X-ray fluorescence (EDXRF) technique. Steady state photoluminescence spectra have been recorded for optical characterization of synthesized nanomaterials. Photo-catalytic activity potential of synthesized nanomaterials under UV radiation exposure has been investigated using methylene blue (MB) dye as a test contaminant in aqueous media. Photo-physical and photo-chemical behaviour dependence on doping concentration has been described in detail. Moreover, the sophistication of competition between charge carrier recombination and charge carrier trapping followed by the competition between recombination of trapped carriers and interfacial charge transfer processes have been presented in a fantastic and elaborative way by comparative study of photoluminescence and photo-catalytic activity results
Seismic Analysis of Soft Storey Buildings Considering Structural and Geometrical Parameters
Get PDFSoft storeys in a high rise building play an important role on its seismic performance. At the soft storey level, there is a discontinuity in the rigidity of the structure due to lack of infill walls or due to variation in floor height. It is this continuity which is the cause of structural failure of multi stored buildings under earthquake loads. In this study, seismic analysis of soft storey building frames have been carried out considering 3 building plans, 15 soft storeys cases and 20 load combinations. Soft storeys have been created by varying the floor heights and effect of infill is ignored. In this way, total 45 frames are analysed. STAAD.pro software has been used for analysis purpose. Results are collected in terms of max. moment, max. storey displacements, max. shear force, max. axial force and max. drift, which are critically analysed to quantify the effects of various parameters