Role of the oceans in climate change -Winter School on Impact of Climate Change on Indian Marine Fisheries held at CMFRI, Cochin 18.1.2008 to 7.2.2008

To maintain the global water balance, the evaporation from oceans worldwide should be balanced by precipitation into the oceans plus runoff from the continents. The earth’s atmosphere contains only 0.001% of the earth’s water, yet it is an important part of the global hydrological cycle. Atmospheric currents carry water vapor to land which gives precipitation and which in turn sustains life on land

Climate change and monsoon -Winter School on Impact of Climate Change on Indian Marine Fisheries held at CMFRI, Cochin 18.1.2008 to 7.2.2008

Even though there has been a substantial increase in carbon dioxide concentration in the atmosphere during the recent decades (see figure 1), global temperatures (both air and water temperatures), have not increased to the extent as predicted by various models. The reason lies in the fact that not only the greenhouse gases, but there are other parameters, such as clouds, aerosols, and the ocean that influence the temperature. Since 1960s, scientists have developed models to understand the ocean’s role in moderating the climate

SPEED SENSOR FAULT DETECTION AND DIAGNOSIS OF INDUCTION MOTOR USING FUZZY BASED FAULT TOLERANT ALGORITHM

This paper presents a three phase squirrel cage induction motor operates using indirect field control is used and speed sensor fault is diagnosis by fuzzy logic control. Induction motors are highly reliable, they are susceptible to many types of faults that can became catastrophic and cause production shutdowns, personal injuries, and waste of raw material. Induction motor faults can be detected in an initial stage in order to prevent the complete failure of the system and unexpected production costs. So,new fault tolerant algorithm is used to detect the faults and  diagnosis the fault, with the help of current estimated and speed estimated blocks. Fault tolerant algorithm was used for diagnosis current and speed sensor faults.Here, IFOC techniques is used to control the switches of the inverter and system performance is analysed. Estimated current control block is used to diagnosis  speed and  current sensor  which is estimated by logic based decision algorithm. In this paper modeling and simulation of three phase induction motor was deceloped using IFOC and fuzzy based new fault tolerant algorithm is also developed by using MATLAB/SIMULINK software

Dynamics of Team Teaching and Research in a Management School: Learning and Imperatives

This paper discusses the experience of team teaching to address the issues of integration of academic inputs by bringing multi-disciplinary perspective together and thereby enhance learning experience of participants. The paper delves on the process, events and outcome of team teaching by four faculty members at IIM Ahmedabad who collaborated in teaching, writing cases, and doing research for a period of more than three years. The experience has been summarized using the following dimensions: need for team-teaching, existing mechanisms and barriers, opportunities and potential, imperatives, fall-outs and challenges experienced in the process. The cohesion, trust and mutual respect are key imperatives. The other factors contributing to the success of team-teaching are strong felt need by the members for integration in programmes, complementary skills and experiences of team members, frequent programmes with integrated components that provided continuous opportunities for learning, co-location of the instructors, and off-site programmes that provided opportunities for close get-togethers. The autonomy granted by the institution to instructors and co-coordinators to design and execute learning opportunities was also instrumental in the success. In an environment where the rule of the game is individualism, forming teams creates fears of loss of importance and recognition. The experience shows that the competency of the members and the overall effectiveness of the tasks are strengthened if the team believes in “reciprocating interdependence”. This can be possible only if members allow themselves opportunities to experiment, improvise and review

How accurate are satellite estimates of precipitation over the north Indian Ocean?

Following the launch of the Global Precipitation Measurement (GPM) Core Observatory in early 2014, motivated from the successful Tropical Rainfall Measurement Mission (TRMM) satellite, an advanced and sophisticated global multi-satellite precipitation product – Integrated Multi- satellitE Retrievals for GPM (IMERG) was released at finer spatio-temporal scales. This precipitation product has been upgraded recently after several refinements and supposed to be superior to other existing global or quasi-global multi-satellite precipitation estimates. In the present study, IMERG precipitation is comprehensively evaluated for the first time against moored buoy observations over the north Indian Ocean at hourly scale for the study period of March 2014 to December 2015. IMERG precipitation performs considerably better over the Bay of Bengal than the Arabian Sea in both detection and estimation. The systematic error in IMERG is appreciably lower by about 14%, however, it generally overestimates in-situ precipitation and also exhibits noticeable false alarms. Furthermore, IMERG essentially shows an improvement over the TRMM Multi-satellite Precipitation Analysis (TMPA) at a daily scale over the north Indian Ocean. IMERG precipitation estimates show overall promising error characteristics, but there is still a need of substantial efforts for improvement in the satellite-based precipitation estimation algorithms especially over data sparse regions such as north Indian Ocean

Effect of incubation time and substrate concentration on N-uptake rates by phytoplankton in the Bay of Bengal

International audienceWe report here the results of three experiments, which are slight variations of the 15N method (JGOFS protocol) for determination of new production. The first two test the effect of (i) duration of incubation time and (ii) concentration of tracer added on the uptake rates of various N-species (nitrate, ammonium and urea) by marine phytoplankton; while the third compares in situ and deck incubations from dawn to dusk. Results indicate that nitrate uptake can be underestimated by experiments where incubation times shorter than 4h or when more than 10% of the ambient concentration of nitrate is added prior to incubation. The f-ratio increases from 0.28 to 0.42 when the incubation time increases from two to four hours. This may be due to the observed increase in the uptake rate of nitrate and decrease in the urea uptake rate. Unlike ammonium [y{=}2.07x{-}0.002\, (r2=0.55)] and urea uptakes [y{=}1.88x{+}0.004 (r2=0.88)], the nitrate uptake decreases as the concentration of the substrate (x) increases, showing a negative correlation [y{=}-0.76x+0.05 (r2=0.86)], possibly due to production of glutamine, which might suppress nitrate uptake. This leads to decline in the f-ratio from 0.47 to 0.10, when concentration of tracer varies from 0.01 to 0.04? M. The column integrated total productions are 519 mg C m-2 d-1 and 251 mg C m-2 d-1 for in situ and deck incubations, respectively. The 14C based production at the same location is ~200 mg C m-2 d-1, which is in closer agreement to the 15N based total production measured by deck incubation

MPPT oscillations minimization in PV system by controlling non-linear dynamics in SEPIC DC-DC converter

Solar PV power generation has achieved rapid growth in developing countries which has many merits such as absence of noise, longer life, no pollution, less time for installation, and ease of grid interface. A maximum power point tracking circuit (MPPT) consists of DC-DC power electronics converters that are used to improve the energy attainment from solar PV array. This paper presents a detailed analysis to control of chaos, a non-linear dynamic in SEPIC DC-DC converter interfaced solar PV system, to minimize the oscillations near to MPP. In SEPIC DC-DC converter, the input inductor current is continuous and capable of sweeping the whole I-V curve of a PV module from open circuit voltage (Voc) to short circuit current (Isc) operating points. To trace the true maximum power point and to nullify the oscillations near to MPP, the yield output voltage needs to ensure period-1 operation

Case Report and Short Communication: Rectal prolapse associated with an unusual combination of pinworms and citrobacter species infection in FVB mice colony

Spontaneous cases of rectal prolapse in a breeding colony of FVB mice were found to be due to infection with Syphacia obvelata and Citrobacter freundii. Microbiology, biochemical and parasitological examination revealed Citrobacter freundii and eggs of Syphacia obvelata. After treatment with antibiotics, antihelminthic drugs and manual reduction prevented further occurrence

Effect of Chemicals and Growth Regulators on Post-Harvest Shelf-Life and Quality in Papaya (Carica papaya L.) Cv. Red Lady

The present investigation on papaya (Carica papaya L.) cv. Red Lady was carried out at Horticultural College and Research Institute, Venkataramannagudem, West Godavari district of Andhra Pradesh, during the year 2010-11. The study was carried out using 9 different treatments involving two chemicals calcium nitrate and calcium chloride at 1, 2, 3 and 4% concentration and two growth regulators, viz., GA3 at 75, 100, 150 and 200mg/l, and BA at 100, 125, 150 and 175mg/l concentration conducted separately in a factorial concept of completely randomized design (CRD), with three replications, under laboratory conditions. Physical parameters studied were per cent fruit ripening, physiological loss in weight (PLW), fruit firmness, shelf-life, and, physic-chemical properties studied were: total soluble solids (TSS), total sugars, reducing sugars, acidity, ascorbic acid and Brix:acid ratio. Fruits treated with CaCl2 @ 4% showed significantly low PLW, per cent fruit ripening, and the highest fruit-firmness, shelf-life, lowest total soluble solids, total sugars, reducing sugars, Brix:acid ratio, and highest acidity and ascorbic acid content, which were on par with CaCl2 @ 2% application. Fruits treated with GA3 @ 100mg/l also exhibited similar results for these parameters. It was concluded that CaCl2 @ 4 % had a beneficial impact on shelf-life of papaya fruits upto 10.67 days without any loss in either physical or physic-chemical properties. Similarly, application of growth regulators such as GA3 and BA @100mg/l significantly increased shelf-life of papaya fruits upto 12 days and 11 days, respectively, while showing the best physical and physico-chemical properties