Dial variations in temperature, salinity and dissolved oxygen from the neritic waters off Cochin during April (peak summer)

Dial variations of important hydrographic parameters were studied continuously for 7 days at a 100 m depth station off Cochin. The frequency of observations varied from 1-3 hourly intervals. In surface waters, the ranges in temperature, salinity and dissolved oxygen values recorded during 10-17 April were 30.64°-32.36°C, 34.56- 34.68 X lO''' and 4.06-4.65 ml/1 respectively. Tlie STD profiles in the diurnal study revealed clearly the premonsoon warming (30°-31°C) in the upper 0-30 m depth zone. In the water column up to 50 m depth, mean salinity values ranged from 34.6 to 35 X 10 while dissolved oxygen values were above 4 mI/1. Time series observations on the production and utilisation of dissolved oxygen revealed wide fluctuation from hour to hour. Vertical gradients in the diurnal study indicated the existence of thermocline around 60 m depth with sharp decline in temperature and dissolved oxygen and increase in salinity below 60 m. The diurnal variation on the distribution of temperature and dissolved oxygen exhibited significant rhythmic tidal impulse of a semi-diurnal wave pattern which was more prominent in the bottom layer below 60 m

Anti-cancer activity of novel dibenzo[b,f]azepine tethered isoxazoline derivatives

10.1186/1472-6769-12-5BMC Chemical Biology12

Thermomagnetic history effects in SmMn2_2Ge2_2

The intermetallic compound SmMn$_2$Ge$_2$, displaying multiple magnetic phase transitions, is being investigated in detail for its magnetization behavior near the 145 K first order ferromagnetic to antiferromagnetic transition occuring on cooling, in particular for thermomagnetic history effects in the magnetization data. The most unusual finding is that the thermomagnetic irreversibility, [= M$^{FCW}$(T)-M$^{ZFC}$(T)] at 135 K is higher in intermediate magnetic field strengths. By studying the response of the sample (i.e., thermomagnetic irreversibility and thermal hysteresis) to different histories of application of magnetic field and temperature, we demonstrate how the supercooling and superheating of the metastable magnetic phases across the first order transition at 145 K contribute to overall thermomagnetic irreversibility.Comment: 15 pages, 5 figures, to appear in Physical Review

Planting methods, subsurface drip fertigation and bioinoculants on growth and productivity of vetiver [Vetiveria zizanioides (L.) Nash]

A field experiment was conducted to study the effect of three planting methods, (planting in coconut husk mulched trenches, planting in coconut husk lined trenches and planting on the ridges), two levels of fertigation (subsurface drip fertigation and without fertigation) and two levels of bioinoculants (combined application of bioinoculants and without bioinoculant) on growth and productivity of vetiver. The study revealed that planting vetiver slips in coconut husk lined trenches could considerably increase vegetative growth, root yield, net returns and B: C ratio. Subsurface drip fertigation and combined application of bioinoculants with Azospirillum, Fluorescent pseudomonads and AM fungi showed positive effect on growth characters and root yield. However, subsurface drip fertigation was not effective in increasing net income. &nbsp

Observations on selected characteristics of water and sediment at the open sea cage culture site of Asian seabass Lates calcarifer (Bloch) off Cochin, south-west coast of India

Study was undertaken to assess the impact of open sea cage culture of Asian seabass Lates calcarifer on selected parameters of water as well as sediment at Munambam off Cochin, Kerala coast from November 2008 to March 2009. Periodic observations were made on temperature, pH, dissolved oxygen, salinity, nutrients (NO3, PO4, SiO3), nitrite, ammonia, BOD, total suspended solids, chlorophyll a, gross and net primary productivity as well as bacterial load of the surface and near bottom water from the cage site (N 10º 08' 162''; E 76º 08' 901'') and also from a reference site (N 10º 07' 189''; E 76º 09' 210'') during pre- as well as post-stocking periods. Sediment samples were collected simultaneously from both the sites and analysed for texture, pH, organic carbon and bacterial load. A significant reduction (p<0.05) in silicate and chlorophyll a was perceived in surface water at the cage site, during the culture period as compared to pre-stocking period. No significant variations were noticed in any of the other parameters studied. The sand, silt, clay and organic carbon content in sediment at cage site differed significantly (p<0.05) from that of the reference site. There was no significant difference in the mean values of total heterotrophic bacterial count as well as presumptive Vibrio count of the water and sediment, either between the cage site and reference site or between the pre- and post-stocking samplings. No adverse effect as influenced by cage culture of fish was observed on any of the environmental parameters studied during the period of investigation

Implementation of Pre Compensation Fuzzy For a Cascade PID Controller Using Matlab Simulink

Fuzzy logic control technology has been widely and successfully utilized in numerous industrial applications. Since fuzzy logic with humanlike but systematic properties can convert linguistic control rule based on expert knowledge into automatic control strategies, it can be well applied to control the process with un modeled and nonlinear dynamics. In this paper a fuzzy logic based pre compensation scheme for PID controller is proposed. Fuzzy methods can be used effectively to implement conventional control methods for performance improvement. The scheme is based on graphically studying the source of steady state errors arising from applying PID type schemes of systems with dead zones. This work is based on trying to compensate for overshoot and undershoot by the transient response. This is easy to implement in practice since an existing PID controller can be used in conjunction with the fuzzy pre compensator without modification Keywords: Fuzzy controller, PID Controller ,Fuzzification, Defuzzification

Study on the Influence of Rapid Prototyping Parameters on Product Quality in 3D Printing

This work aims at evaluating the relative significance of the input parameters on the product quality produced by Z510 3DP rapid fabricator. Taguchi’s L18 orthogonal array was employed to investigate the possible process parameters including binder setting saturation value (shell & core), layer thickness, and build orientation. Using a surface profilometer and CMM, a series of measurements in evaluating the 3DP products surface finish and dimensional accuracy has been carried out. Nonlinear regression model was developed and a statistical analysis was done to determine the significant factors affecting the product quality of the fabricated products. Optimal process parameter settings were proposed using Particle Swarm Optimization technique. The results were validated by conducting the confirmatory experiments.Mechanical Engineerin

Studies on the infestation of an isopod crustacean, Cirolana fluviatilis in some parts of the Cochin backwaters, Kerala

In July 1994 reports appeared in the media about the large scale occurrence of a tiny 'antlike fish killer' in the Kumbalangi-Perumpadappu area of the Cochin backwaters causing threat to the aquatic living resources.The CMFRI initiated an investigation on the problems. The isopod C.Jluviatilis is a commonly occurring organism in the Cochin backwaters and elsewhere. It is a voracious carnivore which if present in very large numbers can cause a threat to the living resources in the estuarine water area. Population explosion of this isopod has now taken place in the Kumbalangi - Perumpadappu area. The reason for the unprecedented population explosion of this isopod in the Kumbalangi- Perumpadappu area is the recent changes taken place in the ecosystem there

Effect of addition of SiC particles on the Microstructure and Hardness of Al-SiC composite

This work aims to investigate the effect of the addition of silicon carbide particles on the microstructure and the hardness of the Al-SiC metal matrix composites. The said composite is prepared using the stir casting technique for different weight percentages of the SiC particles. The higher composition of the reinforcement causes the clustering of the particles in the matrix. Thus, research has to be carried out on the aluminum-silicon carbide composites with the reinforcement 3wt%, 6wt%, 9wt%, and 12wt% of SiC particles to obtain the optimized composition. In order to study the microstructure and the reinforcement distribution in the matrix, a scanning electron microscope is utilized. The hardness testing has been carried out using the Vickers’ indentation technique for the as-cast and age hardening conditions. From the microstructural study, it is observed that the microstructure of the said composite exhibits the uniform distribution of the reinforcement. The EDX results show the presence of the reinforcing elements in the Al-SiC composite. From the results obtained from the hardness testing, it is observed that the presence of the carbide element in the composite increases the hardness of the Al-SiC particulate composites

Planting methods, subsurface drip fertigation and bioinoculants on growth and productivity of vetiver [Vetiveria zizanioides (L.) Nash]

A field experiment was conducted to study the effect of three planting methods, (planting in coconut husk mulched trenches, planting in coconut husk lined trenches and planting on the ridges), two levels of fertigation (subsurface drip fertigation and without fertigation) and two levels of bioinoculants (combined application of bioinoculants and without bioinoculant) on growth and productivity of vetiver. The study revealed that planting vetiver slips in coconut husk lined trenches could considerably increase vegetative growth, root yield, net returns and B: C ratio. Subsurface drip fertigation and combined application of bioinoculants with Azospirillum, Fluorescent pseudomonads and AM fungi showed positive effect on growth characters and root yield. However, subsurface drip fertigation was not effective in increasing net income. &nbsp