Spatial Modeling of Erosion Prone Areas Using GIS

Ponnusamy Malini,Park Ki Youn,Yoo Hwan Hee 대한공간정보학회 2008 대한공간정보학회지 Vol.16 No.3

토양침식은 산악지역에서 산림조성에 중요한 문제를 일으키며 비옥한 토양을 침식시켜 식생의 성장을 저해시키며 인도에서 수집한 자료와 GIS를 이용하여 인도의 서부산맥 모야유역의 토양침식을 분석하였다. 주제도의 레이어로 산림, 지형경사, 배수 등에 대한 자료가 사용되었으며 토양침식 지도분석에서 48%의 지역이 중간정도의 침식을 보였다. 또한 35%지역은 높은 침식을 보였으며 가장 높은 침식은 식생지역의 7%를 차지하였다. 이러한 토양침식 분석도는 유역에서의 토양침식을 방지하기 위한 대책을 수립하는데 주요한 자료가 될 것으로 판단된다. Soil erosion is a major problem in the case of forests in hilly terrains. Soil erosion removes the fertile topsoil, making unsuitable for growth and establishment of vegetation. In the present study, erosion prone areas in a forest region situated in the Moyar sub-watershed of Western ghats was identified using GIS with data collected from India. The thematic layers such as forest cover, slope and drainage density were used for analysis. In the erosion prone map, majority of area (48%) was under medium category, and about 35% of area was under high erosion prone category. Very high erosion prone category occupied 7% of the forest area. This erosion prone map would be an ideal spatial data to take up necessary management actions at appropriate places in this watershed to prevent erosion.

Microbial community and metabolomic comparison of irritable bowel syndrome faeces

Ponnusamy, Kannan,Choi, Jung Nam,Kim, Jiyoung,Lee, Sun-Young,Lee, Choong Hwan Society for General Microbiology 2011 Journal of medical microbiology Vol.60 No.6

<P>Human health relies on the composition of microbiota in an individual’s gut and the synthesized metabolites that may alter the gut environment. Gut microbiota and faecal metabolites are involved in several gastrointestinal diseases. In this study, 16S rRNA-specific denaturing gradient gel electrophoresis and quantitative PCR analysis showed that the mean similarity of total bacteria was significantly different (<I>P</I><0.001) in faecal samples from patients with irritable bowel syndrome (IBS; <I>n</I> = 11) and from non-IBS (nIBS) patients (<I>n</I> = 8). IBS subjects had a significantly higher diversity of total bacteria, as measured by the Shannon index (<I>H′</I>) (3.36<<I>H′</I><4.37, <I>P</I> = 0.004), <I>Bacteroidetes</I> and lactobacilli; however, less diversity was observed for <I>Bifidobacter</I> (1.7<<I> H′</I><3.08, <I>P</I><0.05) and <I>Clostridium coccoides</I> (0.9<<I> H′</I><2.98, <I>P</I> = 0.007). In this study, no significant difference was found in total bacterial quantity (<I>P</I>>0.05). GC/MS-based multivariate analysis delineated the faecal metabolites of IBS from nIBS samples. Elevated levels of amino acids (alanine and pyroglutamic acid) and phenolic compounds (hydroxyphenyl acetate and hydroxyphenyl propionate) were found in IBS. These results were highly correlated with the abundance of lactobacilli and <I>Clostridium</I>, which indicates an altered metabolism rate associated with these gut micro-organisms. A higher diversity of <I>Bacteroidetes</I> and <I>Lactobacillus</I> groups in IBS faecal samples also correlated with the respective total quantity. In addition, these changes altered protein and carbohydrate energy metabolism in the gut.</P>

Removal of cadmium(II) from aqueous solution by agricultural waste cashew nut shell

Ponnusamy Senthil Kumar,Subramanian Sivanesan,Subramaniam Ramalingam,Vasanthakumar Sathyaselvabala,Selvaraj Dinesh Kirupha,Arukkani Murugesan 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.6

Cashew nut shell (CNS) is a low cost adsorbent that has been used for the removal of cadmium(II) from an aqueous solution. The effects of various parameters such as solution pH, CNS concentration, contact time, initial cadmium(II) concentration and temperature were examined. The CNS was effective for the quantitative removal of cadmium(II) ions in acidic conditions and equilibrium was achieved in 30 min. The experimental data were analyzed by two-parameter (Langmuir, Freundlich, Temkin and Dubinin-Radushkevich) and three-parameter models (Redlich-Peterson, Koble-Corrigan, Toth and Sips) by nonlinear regression analysis. The characteristic parameters for each isotherms and related correlation coefficients have been determined by using MATLAB 7.1. Thermodynamic parameters such as ΔGo, ΔHo and ΔSo have also been evaluated, and it was found that the sorption process was feasible, spontaneous and exothermic. Pseudo-first-order, pseudo-second-order, Elovich kinetic and intraparticle diffusion models were selected to follow the adsorption process. The results of the kinetic study show that the adsorption of cadmium(II)could be described by the pseudo-second order equation, suggesting that the adsorption process is presumably chemisorption. A single-stage batch adsorber was designed for different adsorbent dose-to-effluent volume ratios using the Freundlich equation. The results indicate that the cashew nut shell could be used to effectively adsorb cadmium(II)from an aqueous solution.

Kinetics, mechanism, isotherm and thermodynamic analysis of adsorption of cadmium ions by surface-modified Strychnos potatorum seeds

Ponnusamy Senthil Kumar,Rangasamy Gayathri,Chandrasekaran Senthamarai,Muthukumar Priyadharshini,Panimayam Sebastina Anne Fernando,Ramakrishnan Srinath,Vaidyanathan Vinoth Kumar 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.12

The surface-modified Strychnos potatorum seeds (SMSP) were used as an effective low-cost adsorbent for the removal of cadmium ions from aqueous solution. SMSP was characterized by Fourier transform infrared spectroscopy and scanning electron microscopic analyses. The effect of operating variables such as solution pH, adsorbent dose, contact time, initial cadmium ions concentration and temperature on the removal of cadmium ions were studied in a batch mode adsorption operation. The optimum conditions for the adsorption of cadmium ions onto the SMSP were found to be: pH of 5.0, SMSP dose of 2 g/L, contact time of 30min, temperature of 30 oC for an initial cadmium ions concentration of 100 mg/L. Kinetic data were analyzed using the pseudo-first order and pseudo-second order kinetic equations, intraparticle diffusion model, Boyd kinetic model and shrinking core model. The characteristic parameters for each model have been estimated. Adsorption of cadmium ions onto the SMSP follows the pseudo-second order kinetic model. The rate-limiting steps in the adsorption process were found to be external and internal diffusion. Equilibrium data were well described by the Langmuir isotherm model than the Freundlich isotherm model, which yields a maximum monolayer adsorption capacity of 200 mg/g. Thermodynamic parameters such as standard free energy change, enthalpy change and entropy change were also estimated. The results show that the removal of cadmium ions by the SMSP was found to be spontaneous and exothermic.

A new electrode reactor with in-built recirculation mode for the enhancement of methylene blue dye removal from the aqueous solution: Comparison of adsorption, electrolysis and combined effect

Ponnusamy Senthil Kumar,Maria Jacob Stani Raja,Mahathevan Kumaresan,Dinesh Kumar Loganathan,Prabhakaran Chandrasekaran 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.2

The removal of basic dye such as methylene blue (MB) dye from the synthetic wastewater was experimentallyinvestigated using an electrolytic cell (EC), adsorption and the combined effect of EC and adsorption technologycalled a three-phase three-dimensional electrode reactor (TPTDER). The performance of the each technology was checkedon the basis of the efficiency of the systems. The experimental results are expressed in terms of the removal efficiencyof the dye molecules. The results show that the TPTDER could efficiently remove the dye molecules from the aqueoussolutions when compared with the EC and adsorption process. The removal efficiency reached as high as about 99%for an initial MB dye concentration in the range of 100-1,000 mg/L by TPTDER for 10 min at 12 V cell voltage andat specific airflow conditions. It was also observed that the removal of dye molecules depends upon the initial solutionpH, applied cell voltage, contact time, and initial dye concentration. The recyclability of the particle electrodes in theTPTDER process was also checked. These findings suggest that TPTDER is a promising technology for the removalof dyes from the aqueous solution, and can be applied to the removal of dyes from the industrial effluents.

Performance Study on Stabilization of Fine Grained Clay Soils Using Calcium Source Producing Microbes

Ponnusamy Kulanthaivel,Balu Soundara,Arunava Das 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.9

In recent years, the method to produce bio-cementation in sand using bacterial calcium carbonate precipitation (BCCP) process has become more popular. The major objective of this research paper is to study the capability of BCCP to enhance the unconfined compressive strength of clayey soils. Two types of bacteria were used to generate calcium carbonate precipitation. The experimental design variables adopted in this study are bacteria types (L. fusiformis and S. pasteurii), soil types (low compressible clay and intermediate compressible clay), types of externally supplied calcium solution (calcium chloride and eggshell solution), molarities of cementing solution (0.25, 0.50, 0.75 and 1.00 M) and curing period (1, 3 and 7 days). The experimental test results showed that the BCCP process significantly improves the unconfined compressive strength (UCS) of both soils. The improvement however varied with bacterial types, soil types, types of externally supplied calcium solution, molarities of cementing solution and curing period. In BCCP treatment, S. pasteurii treated soils give more strength than L. fusiformis because of high urease activity of S. pasteurii in the order 450 U/ml. The maximum improvement ratio was achieved in CL soil (2.51) compared to CI soil (2.26) due to particle sizes. The optimum externally supplied calcium solution and molarity of cementing medium were established as an eggshell solution and 0.50 M, respectively. The images from scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) analysis confirmed the experimental findings.

NORM ESTIMATES AND UNIVALENCE CRITERIA FOR MEROMORPHIC FUNCTIONS

Ponnusamy, Saminathan,Sugawa, Toshiyuki Korean Mathematical Society 2008 대한수학회지 Vol.45 No.6

Norm estimates of the pre-Schwarzian derivatives are given for meromorphic functions in the outside of the unit circle. We deduce several univalence criteria for meromorphic functions from those estimates.

Removal of methylene blue dye from aqueous solution by activated carbon prepared from cashew nut shell as a new low-cost adsorbent

Ponnusamy Senthil Kumar,Subramaniam Ramalingam,Kannaiyan Sathishkumar 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.1

Methylene blue dye was adsorbed on an adsorbent prepared from cashew nut shell. A batch adsorption study was carried out with variable adsorbent amount, initial dye concentration, contact time and pH. Studies showed that the pH of aqueous solutions affected dye removal as a result of removal efficiency increased with increasing solution pH. The experimental data were analyzed by the Langmuir, Freundlich, Redlich-Peterson, Koble-Corrigan, Toth, Temkin,Sips and Dubinin-Radushkevich models of adsorption using MATLAB 7.1. The experimental data yielded excellent fits within the following isotherm order: Redlich-Peterson>Toth>Sips>Koble-Corrigan>Langmuir>Temkin>Dubinin-Radushkevich>Freundlich, based on its correlation coefficient values. Three simplified kinetic models including a pseudofirst-order, pseudo-second-order and intraparticle diffusion equations were selected to follow the adsorption process. It was shown that the adsorption of methylene blue could be described by the pseudo-second-order equation. The results indicate that cashew nut shell activated carbon could be employed as a low cost alternative to commercial activated carbon in the removal of dyes from wastewater.

An Improved Switching Topology for Single Phase Multilevel Inverter with Capacitor Voltage Balancing Technique

Ponnusamy, Rajan Soundar,Subramaniam, Manoharan,Irudayaraj, Gerald Christopher Raj,Mylsamy, Kaliamoorthy The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.1

This paper presents a new cascaded asymmetrical single phase multilevel converter with a reduced number of isolated DC sources and power semiconductor switches. The proposed inverter has only two H-bridges connected in cascade, one switching at a high frequency and the other switching at a low frequency. The Low Switching Frequency Inverter (LSFI) generates seven levels whereas the High Switching Frequency Inverter (HSFI) generates only two levels. This paper also presents a solution to the capacitor balancing issues of the LSFI. The proposed inverter has lot of advantages such as reductions in the number of DC sources, switching losses, power electronic devices, size and cost. The proposed inverter with a capacitor voltage balancing algorithm is simulated using MATLAB/SIMULINK. The switching logic of the proposed inverter with a capacitor voltage balancing algorithm is developed using a FPGA SPATRAN 3A DSP board. A laboratory prototype is built to validate the simulation results.

An Optimized Bagging Learning with Ensemble Feature Selection Method for URL Phishing Detection

Ponnusamy Ponni,Dhandayudam Prabha 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.3

This study proposes and implements an ensemble feature selection with a bagging classifer for URL phishing detection. Feature Selection is essential for reducing data's dimensionality and improving any proposed framework's performance. The feature selection stability is improved by using the ensemble feature selection method. In this work, Aggregation decides the fnal ranking of the ensemble feature selection by using four standard flter methods. Bagging classifer used for URL phishing dataset and accuracy of the model is determined with aggregation ranked features. In proposed work details the ensemble feature selection methods that embed with optimized ensemble bagging learning. The hyperparameter of the bagging classifer, such as multiple estimators with random patches, random subspaces, bagging, or bootstrap aggregation and pasting, are tuned, which produces the better performance model. The evaluation and comparison of experimental results showed the efectiveness of our method.