Showing papers by "Jadavpur University published in 2003"
TL;DR: The performance of evolutionary programs on ELD problems is examined and modifications to the basic technique are proposed, where adaptation is based on scaled cost and adaptation based on an empirical learning rate are developed.
Abstract: Evolutionary programming has emerged as a useful optimization tool for handling nonlinear programming problems. Various modifications to the basic method have been proposed with a view to enhance speed and robustness and these have been applied successfully on some benchmark mathematical problems. But few applications have been reported on real-world problems such as economic load dispatch (ELD). The performance of evolutionary programs on ELD problems is examined and presented in this paper in two parts. In Part I, modifications to the basic technique are proposed, where adaptation is based on scaled cost. In Part II, evolutionary programs are developed with adaptation based on an empirical learning rate. Absolute, as well as relative, performance of the algorithms are investigated on ELD problems of different size and complexity having nonconvex cost curves where conventional gradient-based methods are inapplicable.
1,207 citations
TL;DR: In this paper, an acid dye, acid yellow 36, was used as the adsorbate for the removal of acid dyes from aqueous solution and the results showed that a pH value of 3 is favorable for the adsorption of acid dye.
926 citations
TL;DR: On neurologic examination, arsenic-typical neuropathy was diagnosed in 63% of the adults, a prevalence previously seen only in severe, subacute exposures, and an apparent increase in fetal loss and premature delivery in the women with the highest concentrations of arsenic in their drinking water.
Abstract: The pandemic of arsenic poisoning due to contaminated groundwater in West Bengal, India, and all of Bangladesh has been thought to be limited to the Ganges Delta (the Lower Ganga Plain), despite early survey reports of arsenic contamination in groundwater in the Union Territory of Chandigarh and its surroundings in the northwestern Upper Ganga Plain and recent findings in the Terai area of Nepal. Anecdotal reports of arsenical skin lesions in villagers led us to evaluate arsenic exposure and sequelae in the Semria Ojha Patti village in the Middle Ganga Plain, Bihar, where tube wells replaced dug wells about 20 years ago. Analyses of the arsenic content of 206 tube wells (95% of the total) showed that 56.8% exceeded arsenic concentrations of 50 micro g/L, with 19.9% > 300 micro g/L, the concentration predicting overt arsenical skin lesions. On medical examination of a self-selected sample of 550 (390 adults and 160 children), 13% of the adults and 6.3% of the children had typical skin lesions, an unusually high involvement for children, except in extreme exposures combined with malnutrition. The urine, hair, and nail concentrations of arsenic correlated significantly (r = 0.72-0.77) with drinking water arsenic concentrations up to 1,654 micro g/L. On neurologic examination, arsenic-typical neuropathy was diagnosed in 63% of the adults, a prevalence previously seen only in severe, subacute exposures. We also observed an apparent increase in fetal loss and premature delivery in the women with the highest concentrations of arsenic in their drinking water. The possibility of contaminated groundwater at other sites in the Middle and Upper Ganga Plain merits investigation.
539 citations
TL;DR: In this article, Fenton's reagent (Fe 2+ and H 2 O 2 ) was used to study the oxidative degradation of two direct dyes, Blue 2B (B54) and Red 12B (R31), in aqueous solution.
491 citations
TL;DR: A literature search on garlic and its antioxidant potential churned up a surprisingly large amount of data, some of it good, some bad and some of its definitely ugly.
Abstract: Garlic has played an important dietary and medicinal role throughout the history of mankind. In some Western countries, the sale of garlic preparations ranks with those of leading prescription drugs. The therapeutic efficacy of garlic encompasses a wide variety of ailments, including cardiovascular, cancer, hepatic and microbial infections to name but a few. However, the elucidation of its mechanism for therapeutic action has proved to be more elusive and a unifying theory, which could account for its reported multifarious activities, is yet to emerge. Reactive oxygen species (ROS) seem to be at the core of many disease processes and it is an attractive and convenient hypothesis that garlic might exert its activities through modulatory effects on ROS. A literature search on garlic and its antioxidant potential churned up a surprisingly large amount of data, some of it good, some bad and some of its definitely ugly. Various preparations of garlic, mainly aged garlic extract (AGE), have been shown to have promising antioxidant potential. However, the presence of more than one compounds in garlic, with apparently opposite biological effects, has added to the complexity of the subject. Raw garlic homogenate has been reported to exert antioxidant potential but higher doses have been shown to be toxic to the heart, liver and kidney. So where do we stand today on this issue of garlic? Is garlic always good for health? How safe is it? Is it necessary to isolate the antioxidant compounds for its medicinal use in a more effective way? These issues are addressed in this review.
390 citations
TL;DR: In this article, the machinability of silicon carbide particulate aluminium metal matrix composite during turning using fixed rhombic tools was investigated during the fabrication of Al/SiC-MMC and the influence of machining parameters, e.g. cutting speed, feed rate and depth of cut on the tools wear and built-up edges (BUEs) were analyzed.
293 citations
TL;DR: In this paper, a morphometric analysis using remote sensing technique has been carried out in parts of Baghmundi block, Purulia district, West Bengal, using satellite imageries of two dates of IRS, different hydrogeomorphological units have been delineated.
Abstract: Remote sensing techniques has proved to be an extremely useful tool in morphometric analysis and groundwater studies. Remote sensing techniques with an emphasis on lineament identifications can play a great role in groundwater prospecting in semi-arid hard rock areas of Purulia district. In the present study, morphometric analysis using remote sensing technique has been carried out in parts of Baghmundi block, Purulia district, West Bengal. The parameters worked out include Bifurcation ratio (Rb), Stream length (Lu), Form factor (Rc), Circulatory ratio (Rc), and Drainage density (D). The morphometric analysis suggests that fractured, resistant, permeable rocks cover the area, the drainage network not so affected by tectonic disturbances. Using satellite imageries of two dates of IRS, different hydrogeomorphological units have been delineated. Among different hydrogeomorphic units (i) very shallow weathered pediment and (ii) Structural hills/ residual hills/inselbergs have very poor ground water prospects, while moderately weathered pediplains and valley fills are good prospective zones for groundwater exploration.
226 citations
TL;DR: An extensive study of the wire lag phenomenon in wire-cut electrical discharge machining has been carried out and the trend of variation of the geometrical inaccuracy caused due to wire lag with various machine control parameters has been established in this paper.
Abstract: An extensive study of the wire lag phenomenon in Wire-cut Electrical Discharge Machining (WEDM) has been carried out and the trend of variation of the geometrical inaccuracy caused due to wire lag with various machine control parameters has been established in this paper. In an extremely complicated machining process like Wire-cut EDM, which is governed by as many as ten control factors, it is very difficult to select the best parametric combination for a particular situation arising out of customer requirements. In the present research study, all the machine control parameters are considered simultaneously for the machining operation which comprised a rough cut followed by a trim cut. The objective of the study has been to carry out an experimental investigation based on the Taguchi method involving thirteen control factors with three levels for an orthogonal array L27 (313). The main influencing factors are determined for given machining criteria, such as: average cutting speed, surface finish characteristic and geometrical inaccuracy caused due to wire lag. Also, the optimum parametric settings for different machining situations have been found out and reported in the paper.
209 citations
TL;DR: Numerical results show that EP-algorithm with better of Gaussian and Cauchy mutations was the best amongst all EPs in terms of convergence rate, solution time and success rate.
182 citations
TL;DR: LiBr catalyses efficiently the three component condensation reaction of an aldehyde, a β-ketoester and urea in refluxing acetonitrile to afford the corresponding dihydropyrimidinones in high yield.
168 citations
TL;DR: In this paper, a transducer operated at the fundamental frequency of 5 MHz in the temperature range from 150 to 480 K was used to measure velocities, attenuation, elastic moduli, Poisson's ratio, Debye temperature and glass transition temperature.
Abstract: Tellurite containing vanadate (50−x)V2O5–xBi2O3–50TeO2 glasses with different bismuth (x=0, 5, 10, 15, 20 and 25 wt%) contents have been prepared by rapid quenching method. Ultrasonic velocities (both longitudinal and shear) and attenuation (for longitudinal waves only) measurements have been made using a transducer operated at the fundamental frequency of 5 MHz in the temperature range from 150 to 480 K. The elastic moduli, Debye temperature, and Poisson’s ratio have been obtained both as a function of temperature and Bi2O3 content. The room temperature study on ultrasonic velocities, attenuation, elastic moduli, Poisson’s ratio, Debye temperature and glass transition temperature show the absence of any anomalies with addition of Bi2O3 content. The observed results confirm that the addition of Bi2O3 modifier changes the rigid formula character of TeO2 to a matrix of regular TeO3 and ionic behaviour bonds (NBOs). A monotonic decrease in velocities and elastic moduli, and an increase in attenuation and acoustic loss as a function of temperature in all the glass samples reveal the loose packing structure, which is attributed to the instability of TeO4 trigonal bipyramid units in the network as temperature increases. It is also inferred that the glasses with low Bi2O3 content are more stable than with high Bi2O3 content.
TL;DR: Among the isomers and metabolites of HCH and DDT, beta-HCH, pp'-DDT and pp'-DDE were found to be dominant and will serve as a baseline against which future anthropogenic effects may be assessed.
TL;DR: The current review focuses on the application of vitamin D and its analogs in different forms of cancer and on the molecular mechanism involved in vitamin D mediated inhibition in cellular proliferation, cell cycle, induction of apoptosis and tumor suppression, which may eventually evolve as a meaningful cancer therapy.
Abstract: The active metabolite of vitamin D, 1alpha, 25-dihydroxyvitamin D3 [1,25(OH)2D3]--a seco-steroid hormone is a pivotal regulator of cellular proliferation and differentiation those are independent of its classical function of calcium homeostasis and bone mineralization. The existence of the nuclear vitamin D receptor (VDR) has been found in numerous tissues in different organs, which are the so-called 'non-classical' targets of this seco-steroid hormone. Vitamin D has been documented as a potent antiproliferative agent in different tissues and cells. Epidemiological studies reveal a negative correlation between physiological level of vitamin and cancer risk. Studies using animal models clearly demonstrate protective role of vitamin D in different cancer types by the reduction in tumor progression and by monitoring biochemical parameters. Experiments with cultured human and animal cancer cell lines show similar antiproliferative role of vitamin D manifested by up or down regulations of crucial genes leading to inhibition of cellular growth. Hypercalcemia hinders broad-spectrum therapeutic uses of vitamin D in cancer chemotherapy. Application of vitamin D analogs having similar chemical structures or other compounds having vitamin D like actions but lacking calcemic adverse effects are getting significant attention towards rational therapeutics to treat cancer. The current review focuses on the application of vitamin D and its analogs in different forms of cancer and on the molecular mechanism involved in vitamin D mediated inhibition in cellular proliferation, cell cycle, induction of apoptosis and tumor suppression, which may eventually evolve as a meaningful cancer therapy.
TL;DR: A single-item single-period Economic Order Quantity model for deteriorating items with a ramp-type demand and Weibull deterioration distribution is considered and the optimal replenishment policy is derived by minimizing the total inventory cost per unit time.
Abstract: A single-item single-period Economic Order Quantity model for deteriorating items with a ramp-type demand and Weibull deterioration distribution is considered. The shortages in inventory are allowed and backlogged completely. The model is developed over an infinite planning horizon and the optimal replenishment policy is derived by minimizing the total inventory cost per unit time. The numerical solution of the model is obtained, and the sensitivity of the parameters involved in the model is also examined.
01 Jan 2003-Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering
TL;DR: Prognosis was favorable in mild and early diagnosed cases of neuropathy whereas most of the other more severe and late diagnosed cases showed slow and partial recovery or even deterioration.
Abstract: Large number of people from 9 out of 18 districts of West Bengal, India are endemically exposed to arsenic contaminated groundwater due to drinking of tubewell water containing arsenic level above World Health Organization's maximum permissible limit of 50 microg/L. From our ongoing studies on neurological involvement in patients of arsenicosis from different districts of West Bengal, we report our findings in a total of 451 patients of three districts (Murshidabad, Nadia, and Burdwan), comprising 267 males and 184 females with age ranging from 11 to 79 years. They all had arsenical skin lesions, positive biomarkers and identified source of arsenic contaminated water drinking. Peripheral neuropathy was the predominant neurological complication in these patients affecting 154 (37.3%) of 413 patients of Group 1 and 33 (86.8%) of 38 patients of Group 2. Other possible causes and alternative explanations of neuropathy were excluded. The temporal profile in most of the cases (154 of Group 1) were of chronic affection while the 33 patients of Group 2 developed both neuropathy and dermopathy subacutely. Subacutely affected Group 2 patients had much higher incidence of neuropathy. Paresthesias and pains in the distal parts of extremities were much higher in incidence in Group 2 (73.7% and 23.7% respectively) than in Group 1 (18.4% and 11.1%). Distal limb weakness or atrophy was evident in 7.3% in Group 1 and 10.5% in Group 2. Overall, sensory features were more common than motor features in patients of neuropathy and sensory neuropathy was diagnosed in 30% and 76.3% and sensorimotor in 7.3% and 10.5% respectively in Group 1 and Group 2 subjects. Nerve conduction and electromyographic studies performed in 88 cases revealed dysfunction of sensory nerve in 45% and 27% and of motor nerve in 20% and 16.7% of patients with moderate degree and mild degree of clinical neuropathies respectively. Evoked potential studies performed in 20 patients were largely normal except for two instances each of abnormal visual evoked potential and brainstem auditory evoked potential findings. Prognosis was favorable in mild and early diagnosed cases of neuropathy whereas most of the other more severe and late diagnosed cases showed slow and partial recovery or even deterioration. Outcome in neuropathic patients of arsenicosis and long term toxic neurologic effects yet unexplored and unknown remain as matters of future concern requiring close monitoring.
TL;DR: In this article, the influence of the predominant electrochemical process parameters such as machining voltage, electrolyte concentration, pulse on time and frequency of pulsed power supply on the material removal rate (MRR) and accuracy has been investigated.
Abstract: Non-conventional machining is increasing in importance due to some of the specific advantages which can be exploited during micromachining operation. Electrochemical micromachining (EMM) appears to be a promising technique, since in many areas of application, it offers several special advantages that include higher machining rate, better precision and control, and a wider range of materials that can be machined. A better understanding of high rate anodic dissolution is urgently required for EMM to become a widely employed manufacturing process in the micro-manufacturing domain. An attempt has been made to develop an EMM experimental set-up for carrying out in depth research for achieving a satisfactory control of the EMM process parameters to meet the micromachining requirements. Keeping in view these requirements, sets of experiments have been carried out to investigate the influence of some of the predominant electrochemical process parameters such as machining voltage, electrolyte concentration, pulse on time and frequency of pulsed power supply on the material removal rate (MRR) and accuracy to fulfil the effective utilization of electrochemical machining system for micromachining. A machining voltage range of 6 to 10 V gives an appreciable amount of MRR at moderate accuracy. According to the present investigation, the most effective zone of pulse on time and electrolyte concentration can be considered as 10–15 ms and 15–20 g/l, respectively, which gives an appreciable amount of MRR as well as lesser overcut. From the SEM micrographs of the machined jobs, it may be observed that a lower value of electrolyte concentration with higher machining voltage and moderate value of pulse on time will produce a more accurate shape with less overcut at moderate MRR. Micro-sparks occurring during micromachining operation causes uncontrolled material removal which results in improper shape and low accuracy. The present experimental investigation and analysis fulfils various requirements of micromachining and the effective utilization of ECM in the micromachining domain will be further strengthened.
TL;DR: P-type transparent conducting thin films of copper aluminium oxide were prepared by DC sputtering of polycrystalline CuAlO 2 target, which was fabricated by heating a stoichiometric mixture of Cu 2 O and Al 2 O 3 at 1375 K for 24 hours as discussed by the authors.
TL;DR: Clitoria ternatea roots methanol extract when given by oral route to rats was found to inhibit both the rat paw oedema caused by carrageenin and vascular permeability induced by acetic acid in rats.
01 Jan 2003-Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering
TL;DR: A followup study indicates that many of the victims suffering from severe arsenical skin lesions for several years are now suffering from cancer or have already died of cancer.
Abstract: To understand the magnitude of the arsenic calamity in West Bengal, a detailed study spanning 7 years was made in North 24-Parganas, one of the nine arsenic affected districts. Area and population of North 24-Parganas district are 4093.82 sq. km and 7.3 million, respectively. Fourty eight thousand and thirty water samples were analyzed from hand tubewells of North 24-Parganas in use for drinking, cooking and 29.2% of the tubewells were found to have arsenic above 50 microg/L, the maximum permissible limit of World Health Organization (WHO) and 52.8% have arsenic above 10 microg/L, WHO recommended value of arsenic in drinking water. Out of the 22 blocks of North 24-Parganas, in 20 blocks arsenic has been found above the maximum permissible limit and so far in 16 blocks people have been identified as suffering from arsenical skin lesions. From the generated data, it is estimated that about 2.0 million and 1.0 million people are drinking arsenic contaminated water above 10 microg/L and 50 microg/L level, respectively in North 24-Parganas alone. So far, in our preliminary study 33,000 people have been examined at random from arsenic affected villages in North 24-Parganas and 2274 people have been registered with arsenical skin lesions. Extrapolation of the available data indicates about 0.1 million people may be suffering from arsenical skin lesions from North 24-Parganas alone. A sum of 21,000 hair, nail, and urine samples analyses from arsenic affected villages show 56%, 80%, and 87% people have arsenic in biological specimen more than normal/toxic (hair) level, respectively. Thus, many may be subclinically affected. Due to use of arsenic contaminated groundwater for agricultural irrigation, rice and vegetable are getting arsenic contaminated. Hence there is an additional arsenic burden from food chain. People from arsenic affected villages are also suffering from arsenical neuropathy. A followup study indicates that many of the victims suffering from severe arsenical skin lesions for several years are now suffering from cancer or have already died of cancer.
TL;DR: Results of comparative study show much improvement of transient responses in terms of settling times, undershoots, overshoots and df/dt in favor of GA based gains for non-reheat systems, and to get better optimal performance GA based optimal gains have also been determined for three-area system.
TL;DR: G. biloba is more effective in AS, whereas for CS, P. ginseng will be a better option, and these extracts possess significant anti-stress properties and can be used for the treatment of stress-induced disorders.
TL;DR: In this article, the abrasive wear behaviour of different hardfacing electrodes deposited on grey cast iron used for the top bearing plate of a coal crushing unit was studied using the dry sand rubber wheel abrasion test.
TL;DR: An order-level inventory problem is discussed with the demand rate being represented by a continuous, quadratic function of time, assumed that a constant fraction of the on-hand inventory deteriorates per unit of time.
TL;DR: In this article, the authors synthesize and interpret available lithological, petrological and geochronological data on the rocks of the Eastern Ghats Belt (EGB), which has a key role to play in any model of Indo-Antarctic correlation in Precambrian and Cambrian times, have been synthesized and interpreted.
Abstract: Available lithological, petrological and geochronological data on the rocks of the Eastern Ghats Belt (EGB), which has a key role to play in any model of Indo-Antarctic correlation in Precambrian and Cambrian times, have been synthesized and interpreted. Longitudinal lithological subdivisions of the belt are mostly not supported by recent geochronological data, which rather suggest a fourfold division based on protolith ages of the ortho- and paragneisses. Mineral ages show prominent tectonothermal events at Mesoproterozoic, Grenvillian and Pan-African times. However, not all of the imprints of all the events are preserved in all the geochronological domains. In the most well-studied Domain II, three phases of metamorphism are recorded -an early ultra high-temperature metamorphism with an anticlockwise P-T path, a second granulite facies event at c. 1000 Ma, with a retrograde trajectory of near-isothermal decompression, and a third of amphibolite facies. The available information, however, is not conclusive as to whether or not the entire EGB experienced polyphase UHT metamorphism. The propagation of the Grenvillian orogenic front in the EGB is identified.
TL;DR: The magnetic behavior of the tetranuclear copper(II) complex, synthesized and characterized by spectroscopic methods, X-ray single-crystal analysis, and variable-temperature magnetic measurements, indicates that the interactions between copper ions are antiferromagnetic in nature for both azido and phenoxo bridges.
Abstract: A novel tetranuclear copper(II) complex containing alternating μ 1 , 1 -azido and monophenoxo bridges has been synthesized and characterized by spectroscopic methods, X-ray single-crystal analysis, and variable-temperaturemagnetic measurements. The magnetic behavior, investigated in the temperature range 2-300 K, indicates that the interactions between copper ions are antiferromagnetic in nature for both azido and phenoxo bridges. The temperature dependence of the magnetic susceptibility was fitted with J 1 = -12.8 cm - 1 , J 2 = -10 cm - 1 , g = 2.171, 2.1% paramagnetic component, and negligible temperature-independent paramagnetism (5 x 10 - 8 ). At variance with the earlier reports of these types of complexes containing a μ 1 , 1 -azido group, the end-on double-azido-bridged copper(II) center in this complex shows an antiferromagnetic interaction.
01 Jan 2003-Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering
TL;DR: Urinary arsenic is generally considered as the most reliable indicator of recent exposure to inorganic arsenic and is used as the main bio-marker of exposure and results indicate that children retain less arsenic in their body than adults.
Abstract: Urinary arsenic is generally considered as the most reliable indicator of recent exposure to inorganic arsenic and is used as the main bio-marker of exposure. However, due to the different toxicity of arsenic compounds, speciation of arsenic in urine is generally considered to be more convenient for health risk assessment than measuring total arsenic concentration. Additionally, it can give valuable information about the metabolism of arsenic species within the body. In our study, for exposed group—42 urine samples were collected from Datterhat (South) village of Madaripur district, Bangladesh and an average arsenic concentration in their drinking water was 376 µg/L (range 118 to 620 µg/L). For control group, 27 urine samples were collected from a non-affected district, Badhadamil village of Medinipur district, West Bengal, India, where arsenic concentration in their drinking water is below 3 µg/L. The arsenic species in the urine were separated and quantified by using HPLC-ICP-MS. The sum of ino...
TL;DR: In this paper, an analytical approach for the solution of the wire-tool vibration equation considering multiple spark discharges to investigate the characteristic effects of wire vibration in wire-cut electrical discharge machining is presented.
TL;DR: In this article, the authors presented numerical prediction of characteristics of laminar, as well as, turbulent flow and heat transfer in a square sectioned duct inserted with a twisted tape, whose width equals the length of the duct side.
TL;DR: The present paper deals with the problem of combined harvesting of two competing fish species, each of which obeys the law of logistic growth and releases a substance toxic to the other.
TL;DR: In this article, the experimental results and analysis on EMM will open up more application possibilities for EMM, which is considered to be one of the most effective advanced future micromachining techniques.