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A Novel Method of Image Compression Using Multiwavelets and Set Partitioning Algorithm
U.S. Ragupathy,A. Tamilarasi
Modern Applied Science , 2009, DOI: 10.5539/mas.v3n2p134
Abstract: Advances in wavelet transforms and quantization methods have produced algorithms capable of surpassing the existing image compression standards like the Joint Photographic Experts Group (JPEG) algorithm. The existing compression methods for JPEG standards are using DCT with arithmetic coding and DWT with Huffman coding. The DCT uses a single kernel where as wavelet offers more number of filters depends on the applications. The wavelet based Set Partitioning In Hierarchical Trees (SPIHT) algorithm gives better compression. For best performance in image compression, wavelet transforms require filters that combine a number of desirable properties, such as orthogonality and symmetry, but they cannot simultaneously possess all of these properties. The relatively new field of multiwavelets offer more design options and can combine all desirable transform features. But there are some limitations in using the SPIHT algorithm for multiwavelets coefficients. This paper presents a new method for encoding the multiwavelet decomposed images by defining coefficients suitable for SPIHT algorithm which gives better compression performance over the existing methods in many cases.
Experimental Determination of Heat Transfer Coefficient in Stirred Vessel for Coal-Water Slurry Based on the Taguchi Method
C. M. Raguraman,A. Ragupathy,L. Sivakumar
Journal of Engineering , 2013, DOI: 10.1155/2013/719296
Abstract: Heat transfer in stirred vessels is important because process fluid temperature in the vessel is one of the most significant factors for controlling the outcome of process. In this study, the effects of some important design parameters for coal-water slurry in agitated vessel used in coal gasification such as stirrer speed, location of stirrer, D/d ratio, and coal-water ratio were investigated and optimized using the Taguchi method. The experiments were planned based on Taguchi’s orthogonal array with each trial performed under different levels of design parameter. Signal-to-noise (S/N) analysis and analysis of variance (ANOVA) were carried out in order to determine the effects of process parameter and optimal factor’s level settings. Finally, confirmation tests verified that the Taguchi method achieved optimization of heat transfer coefficient in agitated vessel. 1. Introduction Research on heat transfer coefficient in agitated vessel is still critical and ongoing. Heat transfer in stirred vessel is important because process fluid temperature in the vessel is one of the most significant factors for controlling the outcome of process. Mechanically agitated vessels are widely used in mining, food, petroleum, chemical, pharmaceutical, pulp, and paper industries and are also used in coal gasification power plant [1]. The intensity of heat transfer during mixing of fluids like coal slurry depends on the type of the stirrer, the design of the vessel, and condition of the processes [2]. In this study the effects of some important parameters such as stirrer speed, location of stirrer, D/d ratio, and coal-water ratio were investigated and optimized. Performing an experiment is more suitable for determination of the real performance characteristics of a system. However to prepare an experimental setup is very expensive and some systems cannot be constructed and tested in a laboratory. Also, preparing an experimental setup is a very time-consuming procedure because of the high trial numbers. Because of these difficulties, the modeling and then testing the system using numerical analysis, ANN (artificial neural network), or optimizing the trial numbers according to the Taguchi method is more appropriate and very popular nowadays [3]. Heat transfer rates in agitated vessel have been investigated for coal-water slurry in a flat bottom vessel equipped with flat-blade impeller making an angle of 45 degree to the axis of the shaft. Also the heat transfer coefficients of the flat-blade impeller parallel to the axis of the shaft results [4] were compared. 2. Experimental
Effective Extraction of Heavy Metals from their Effluents Using Some Potential Ionic Liquids as Green Chemicals
A. Rajendran,D. Ragupathy,M. Priyadarshini,A. Magesh
Journal of Chemistry , 2011, DOI: 10.1155/2011/202380
Abstract:
An environmentally benign one pot synthesis of substituted quinolines catalysed by fluoroboric acid based ionic liquid
A Rajendran,C Karthikeyan,D Ragupathy,K Rajathi
- , 2012,
Abstract:
THE STRESS IMPACT ON MECHANICAL PROPERTIES OF ROCKS IN HYDRO FRACTURING TECHNIQUE
B. GURUPRASAD,Dr.A. RAGUPATHY,T.S. BADRINARAYANAN,K.B. RAJKUMAR
International Journal of Engineering Science and Technology , 2012,
Abstract: Ground water is considered to be the best safe protected drinking water source and bore wells are drilled in hard crystalline rock terrains for drinking water, irrigation and industrial purposes. Even after scientific location, some bore wells yield inadequate quantity of water or fail to yield. The success of bore wells depend largely onnumber, length, dilation and interconnectivity of fractures encountered on drilling. Considering the cost factor involved in drilling a new bore well, rejuvenation of failed bore well through some technique is thought off. The innovative technology of ‘hydro fracturing’ is a new interdisciplinary approach of Hydro mechanical tostimulate the bore well to improve the yield by applying water pressure into bore well by using a heavy duty mechanical compressor. The hydro fracturing technique was first used in oil well to increase oil and gas production. In this research paper, the hydraulic pressure applied increases with depth reflecting the rigidness,toughness of rock. The fracture development, propagation of fracture and stress behavior depends on the physical and mechanical properties of rocks. The hydro fracturing process has been conducted in three depth zones ranging from 8 m to 45 m below ground level in Annavasal union of Pudukottai district, Tamil Nadu, India. The Pressure application varies depending on the geological formations. This study pertains to a part of research work. The minimum and maximum pressures applied are 1 and 10 N/mm2 respectively. The maximumpressure of 10 N/mm2 has been recorded in the third zone, where the country rock is charnockite which is generally massive, compact and dense rock. Generally for the igneous rock in the third zone in the depth range of 40 to 50 m, more than 7 N/mm2 of pressure has been applied indicating extremely strong nature with uniaxial compressive strength 100 – 300 N/mm2, tensile strength 7- 25 N/mm2. Out of 37 bore wells 32.4% of bore wells have shown 75% yield improvement, 40.5% have shown 50 to 75% improvement and 21.9% shown 25 to50% improvement.
Estimation of Fracture Length as a Mechanical Property in Hydrofraturing Technique using an Experimental Setup
B. Guruprasad,A. Ragupathy,T.S. Badrinarayanan,R.Venkatesan
International Journal of Engineering and Technology , 2012,
Abstract: This paper compares temperature distribution and weld bead profiles of constant current and pulsed current gas tungsten arc welded AISI 304L grade stainless steel joints. The effects of pulsed current welding on tensile properties, hardness profiles, micro structural features and residual stress distribution of stainless steel joints are reported. The use of pulsed current technique improves the tensile properties of the welds compared to those of continuous current welds due to grain refinement occurring in the fusion zone.
An effect of Blade geometry on heat transfer performance in stirred vessel – coal water slurry system using coal gasification
C.M.Raguraman,,A. Ragupathy,R. Ramkumar,,L. Sivakumar
International Journal of Engineering Science and Technology , 2010,
Abstract: The effect of the geometrical parameter of blades on heat transfer co-efficient were experimentally studied for agitated vessels using coal slurry in coal gasification. The intensity of hear transfer during mixing of fluids depends on the type of the stirrer, the design of the vessel and conditions of the process. The type and size of the stirrer, as well as its location in the vessel, also affect the rate of hear transfer. In this study, the effect of some importantdesign parameter such as the type of stirrer, angle and shape of blades, number of blades and location of stirrer, etc., were investigated and optimized. Besides, the Taguchi method can successfully be applied to heat transfer investigation to save energy, time and material in experimentation.
DEVELOPING AN EMPIRICAL RELATIONSHIP TO PREDICT THE FRACTURE LENGTH IN HYDRO FRACTURING PROCESS
B.Guruprasad,A.Ragupathy,T.S.Badrinarayanan
International Journal of Advances in Engineering and Technology , 2013,
Abstract: When mechanically induced progressive failure of rock and the associated changes in hydro fracturing process, it is difficult to track the dynamic evolution of fractures beneath the earth. To overcome this, recent developments in hydro-fracturing technique have tended to follow hybrid approaches. An attempt was made to develop an empirical relationship to predict the Fracture length in millimeters of Hydro fracturing process using RSM technique. Three factors and a central composite design were used to minimize the number of experimental conditions. Response surface method was used to develop their relationship. The developed relationship can be effectively used to predict the Fracture length as a mechanical property in Hydro fracturing process at 95% confidence level whereby the most pertinent aspects of each of the continuum and discrete approaches are combined.
Experimental study of cooling tower performance using ceramic tile packing
Ramkumar Ramkrishnan,Ragupathy Arumugam
Processing and Application of Ceramics , 2013, DOI: 10.2298/pac1301021r
Abstract: Deterioration of the packing material is a major problem in cooling towers. In this experimental study ceramic tiles were used as a packing material. The packing material is a long life burnt clay, which is normally used as a roofing material. It prevents a common problem of the cooling tower resulting from corrosion and water quality of the tower. In this study, we investigate the use of three different types of ceramic packings and evaluate their heat and mass transfer coefficients. A simple comparison of packing behaviour is performed with all three types of packing materials. The experimental study was conducted in a forced draft cooling tower. The variations in many variables, which affect the tower efficiency, are described.
SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION OF DIACEREIN AND ACECLOFENAC IN TABLETS BY CHEMOMETRIC METHODS
Vijayageetha Ragupathy,Shantha Arcot
International Research Journal of Pharmacy , 2013, DOI: 10.7897/2230-8407.04345
Abstract: Simultaneous spectrophotometric determination of diacerein and aceclofenac was performed by partial least-squares (PLS) and principal component regression (PCR) methods do not require any priori graphical treatment of the overlapping spectra of two drugs in the mixture. The absorbance values in the UV-Vis spectra were measured for the 67 wavelength points (from 234-300) in the spectral region 200–400 nm considering the intervals of 1 nm. The calibration range was found to be 1-5 μg/ml for diacerein, 2-10 μg/ml for aceclofenac with a correlation coefficient of 0.9998(PLS), 0.9995(PCR) for diacerein and 0.9999 (PLS), 0.9997 (PCR) for aceclofenac. The validation of the multivariate methods was realized by analyzing the synthetic mixtures of diacerein and aceclofenac. The numerical calculations were performed with the ‘Unscrambler 10.1 X’ software. The chemometrics analysis methods were satisfactorily applied to the simultaneous determination of diacerein and aceclofenac in the pharmaceutical formulation.
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