251 research outputs found
Development of cost-effective phasor measurement unit for wide area monitoring system applications
Sustained growth in the demand with unprecedented investments in the transmission infrastructure resulted in narrow operational margins for power system operators across the globe. As a result, power networks are operating near to stability limits. This has demanded the electrical utilities to explore new avenues for control and protection of wide area systems. Present supervisory control and data acquisition/energy management systems (SCADA/EMS) can only facilitate steady state model of the network, whereas synchrophasor measurements with GPS time stamp from wide area can provide dynamic view of power grid that enables supervision, and protection of power network and allow the operator to take necessary control/remedial measures in the new regime of grid operations. Construction of phasor measurement unit (PMU) that provide synchrophasors for the assessment of system state is widely accepted as an essential component for the successful execution of wide area monitoring system (WAMS) applications. Commercial PMUs comes with many constraints such as cost, proprietary hardware designs and software. All these constraints have limited the deployment of PMUs at high voltage transmission systems alone. This paper addresses the issues by developing a cost-effective PMU with open-source hardware, which can be easily modified as per the requirements of the applications. The proposed device is tested with IEEE standards
Directional Correlation Study of Gamma Cascades in the Decay of Sb124
The delay scheme of sb124 studied and the gamma-gamma directional correlation measurements are carried out for few cascades.On the basis of the experimental data on directional correlations, the spin assignments are made for the 603, 1326, 1964, 2313, 2688 keV excited levels of Te124. Multipole assignments are made for 989, 1362 keV transitions
Catalytic non-thermal plasma reactor for the decomposition of a mixture of volatile organic compounds
The decomposition of mixture of selected volatile organic compounds (VOCs) has been studied in a catalytic non-thermal plasma dielectric barrier discharge reactor. The VOCs mixture consisting n-hexane, cyclo-hexane and p-xylene was chosen for the present study. The decomposition characteristics of mixture of VOCs by the DBD reactor with inner electrode modified with metal oxides of Mn and Co was studied. The results indicated that the order of the removal efficiency of VOCs followed as p-xylene > cyclo-hexane > n-hexane. Among the catalytic study, MnOx/SMF (manganese oxide on sintered metal fibres electrode) shows better performance, probably due to the formation of active oxygen species by in situ decomposition of ozone on the catalyst surface. Water vapour further enhanced the performance due to the in situ formation of OH radicals. [Figure not available: see fulltext.
MGS Studies for Recovering Iron and Silver Values from Lead-Zinc Tailings
In mineral processing plants valuable minerals are recovered by rejecting gangue materials through various physical processing techniques to produce high-grade concentrate. However, after processing these ores, the tailings generated contain considerable amount of valua-bles because of inefficient of process plant or due to fluctuations in the mineralogical composition of the ore. Therefore, recovery of these valuable minerals is prerequisite from environmental and mineral conservation point of views
Isolation and Characterisation of Electrogenic Bacteria from Mud Samples
To develop efficient microbial fuel cell systems for green energy production using different waste products, establishing characterised bacterial consortia is necessary. In this study, bacteria with electrogenic potentials were isolated from mud samples and examined to determine biofilm-formation capacities and macromolecule degradation. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry identifications have revealed that isolates represented 18 known and 4 unknown genuses. They all had the capacities to reduce the Reactive Black 5 stain in the agar medium, and 48 of them were positive in the wolfram nanorod reduction assay. The isolates formed biofilm to different extents on the surfaces of both adhesive and non-adhesive 96-well polystyrene plates and glass. Scanning electron microscopy images revealed the different adhesion potentials of isolates to the surface of carbon tissue fibres. Eight of them (15%) were able to form massive amounts of biofilm in three days at 23 °C. A total of 70% of the isolates produced proteases, while lipase and amylase production was lower, at 38% and 27% respectively. All of the macromolecule-degrading enzymes were produced by 11 isolates, and two isolates of them had the capacity to form a strong biofilm on the carbon tissue one of the most used anodic materials in MFC systems. This study discusses the potential of the isolates for future MFC development applications
Role of Technology and Credit in Improving Farm Incomes in Rainfed Regions in Andhra Pradesh
Improving the productivity of rainfed agriculture and income of farmers is important to achieve sustainable
and equitable growth. This paper has examined the role of technology and credit, the two important
factors of agricultural growth, in increasing farm incomes using farm-level data from three rainfed districts,
namely Adilabad, Mahabubnagar and Rangareddy of Andhra Pradesh for the year 2010-2011. For the
study, optimum crop plans were developed in a linear programming framework, and the results have
indicated considerable scope for enhancing farm incomes by re-allocation of resources, adoption of
improved technologies and enhancing access to capital or credit. Improved technology could increase
the net returns of farmers by 20-84 per cent, depending upon their farm categories in the study districts.
In the absence of credit, the net returns declined up to 80 per cent, especially for small farmers. In the
absence of credit, the suggested optimum farm plans are not income-maximizing, and were found to lead
to inefficient use of resources, especially of land
Assessing unrealized yield potential of maize producing districts in India
The projected demand of maize production in India in
2050 is 4–5 times of current production. With the
scope for area expansion being limited, there is need
for enhancement of yield. This calls for identifying
areas where huge unrealized yield potential exists.
With a view to address the issue, the present study
delineates homogeneous agro-climatic zones for maize
production system in India taking district as a unit
and using the factors production, viz. climate, soil,
season and irrigated area under the crop. There are
146 districts in India that grow maize as a major crop.
They were divided into 26 zones using multivariate
cluster analysis. Study of variation in yield between
districts within a zone vis-à-vis crop management
practices adopted in those districts was found useful
in targeting the yield gaps. These findings can have
direct relevance to the maize farmers and district level
administrators
Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease
Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.
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