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1.
Thirunavukkarasu Muralisankar Periyakali Saravana Bhavan Subramanian Radhakrishnan Perumal Santhanam 《中国海洋湖沼学报》2019,37(1):290-299
Journal of Oceanology and Limnology - A feeding experiment was conducted to evaluate the effects of bulk zinc (B-Zn) and zinc nanoparticles (Zn-NPs) on survival, growth, compositions of amino acid... 相似文献
2.
Sanjeev P. Deshpande K. V. Radhakrishnan U. Gopalakrishna Bhat 《Journal of the Indian Society of Remote Sensing》2011,39(4):547-554
The technique of predicting Potential Fishing Zone using satellite derived sea surface temperature and chlorophyll is becoming
an important aspect for the fishermen. In the present study an attempt has been made to compare fish density/catch per unit
effort in the areas predicted by Satellite imagery and available to fishermen via electronic display boards at the fish landing
centers of Uttara Kannada district, Karnataka with those of non predicted areas. Direct and Indirect validation was done.
Direct method means comparing the catch using fishing vessels simultaneously in the notified region with that of catch from
non notified region. And in indirect method by comparing catch data from landing centers on notified days with that of non
notified days. Direct validation off Karwar showed that catch was significantly higher in notified (PFZ) area with high densities
as compared to non notified (non PFZ) regions. When comparisons of landing center data of Karwar, Tadadi and Bhatkal are done
it is evident that in all the centers during the period under study, higher catches were observed on notified days than non
notified days except in Bhatkal centre in 2009–10. There by validating the accuracy of PFZ predictions and economic gains
to fishermen. 相似文献
3.
Subramani Saravanan Govindan Nagarajan Radhakrishnan Ramanujam Santhanam Sampath 《洁净——土壤、空气、水》2011,39(6):515-521
The main objective of this work is to investigate the factors influencing the NOx control of a stationary diesel engine fuelled with crude rice bran oil blend with lesser effect on smoke density and brake thermal efficiency (BTE). Fuel injection timing, percentage of EGR, and fuel injection pressure are chosen as the factors for the objective and NOx emission, smoke density, and BTE are considered as the response variables. To critically analyze the effects of the chosen factors on the objective three levels were chosen in each factor and the experiments were designed by following the design of experiments method. Taguchi's L9 orthogonal array was used to conduct the tests with different combination of factor levels. Through analysis of variance (ANOVA) method, the most influencing factors and also the significance of each factor affecting each response variable were found out. Response graph was drawn for each response variable to determine the optimum combination of factor levels in achieving the objective and the obtained combination was confirmed experimentally. 相似文献
4.
P. V. Hareesh Kumar A. Raghunadha Rao K. Anilkumar M. Padmanabham K. G. Radhakrishnan 《Natural Hazards》2011,57(3):643-656
Analysis of the time series data collected from a stationary location in the continental shelf of the southeastern Arabian
Sea during different month indicated prominent internal wave (IW) activity. Time evolution of temperature, resolved using
Morlet wavelet technique, revealed that maximum energy was concentrated in the diurnal band at the density interface, whereas
within the interior of thermocline, the dominant energy concentration shifted to semi-diurnal band. Both these harmonics have
maximum amplitude (>15 m) during the pre-monsoon and monsoon season when the water column was highly stratified (>0.05 kg/m4), but they were not discernable in the temperature record when the stratification was weak (i.e., especially during winter).
An acoustic propagation model based on ray theory, Bellhop (http:/oalib.hlsresearch.com/modes/acoustictoolbox/at.zip) was
utilized to compute the transmission loss (TL) associated with the passage of low-frequency IWs. The TL was computed using
the model considering (1) range-dependent and range-independent environmental scenario and (2) for different source and receiver
depth configurations. Intermittent fading of acoustic signals was observed in the presence of IW. It was also observed that
fading of signals very much depends on the source–receiver configuration. 相似文献
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The observed proper-motions are shown to indicate that most pulsars come from binary systems. Due to a remarkable relationship between the speed of a pulsar and that of its progenitor in orbit, it is concluded that these binaries went through a common-envelope phase. This provides independent support to similar conclusions drawn from stellar evolution considerations.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
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8.
Radhika Radhakrishnan Santu Kuzhikandathil Sunny Bijoy Nandan Sivasankaran Harikrishnan Mahadevan 《Marine Ecology》2020,41(6):e12619
The cruise conducted in the spring inter-monsoon (pre-monsoon) of April 2015 in the frame of a funded project epitomized an open ocean survey that allowed procuring a quasi-synoptic picture of cyclopoid copepod community structure in 18 open ocean stations of the Minicoy Island, Lakshadweep archipelago, off the southwestern Indian coast, based on the analysis of standing stock and composition in the integrated 0–10 m water column. The main objective was to explore the community structure of cyclopoid copepods prevailing here and which environmental variable influences the same. It is witnessed that sea surface temperature (SST) (30.42 ± 0.19°C), sea surface salinity (SSS) (33.56 ± 1.15 psu), and dissolved oxygen (DO) (4.32 ± 0.06 ml/L) with SSS and DO are the best matching variables diversifying cyclopoid copepod species (av. abundance 700 ± 386 no. of individuals/100 m3). Average zooplankton biomass (0.03 ml/m3) and abundance (8,989 ± 3,866 no. of individuals/100 m3) were also observed. Fifty-one cyclopoid copepod species belonging to four families and seven genera were identified, with the dominance of high saline species such as Sapphirina, Copilia, Farranula, and Oncaea. An abundance biomass curve (ABC) plot analysis indicated an undisturbed community with normal environmental conditions. TAXDTEST (taxonomic distinctness) depicted a diverse condition where all points clustered together within a 95% confidence level. Our results indicate that the cyclopoid copepod assemblage near Minicoy Island is a diverse, undisturbed community and hypothesize that the stable environmental conditions during pre-monsoon (spring inter-monsoon) preferred the diversification of cyclopoid copepods with the prevalence of high saline species. The data evolved could be used as a standard reference/benchmark to detect any deviation from an undisturbed/diverse community status of Minicoy Island in the looming scenario of climate change in and around the Indian Ocean. 相似文献
9.
We use the recently introduced concept of a ‘window’ of magnetic field strengths in which pulsars can be active to explain
the variation in morphology of supernova remnants. The striking difference between shell-type and filled-type remnants is
attributed to differences in he magnetic field strengths of the neutron stars left by the respective Supernovae. Field strengths
of a value permitting pulsar activity result in particle production and Crab-like centrally concentrated remnants. Other field
values lead to strong magnetic dipole radiation and consequent shell formation (e.g. Cas A). Several apparent inconsistencies concerning pulsar-supernova associations appear to find a logical explanation on
the basis of this hypothesis. 相似文献
10.
A 21 cm absorption measurement over a long path length free of the effects of differential galactic rotation indicates the
existence of two distinct cloud populations in the plane. One of them consisting of cold, dense clouds has been well studied
before. The newly found hot clouds appear to be at least five times more numerous. They have a spin temperature of ~ 300 K,
an rms velocity of ~ 35 km s-1, twice the total mass, and hundred times the kinetic energy of the cold clouds. Over long path lengths, the hot clouds haveN
H/kpc ~ 2 X 1021 cm-2 Kpc-1, and are estimated to have individual column densities ≤ 1020 cm-2. We propose that they are shocked clouds found only within supernova bubbles and that the cold clouds are found in the regions
in-between old remnants, immersed in an intercloud medium. We conclude that the solar neighbourhood must be located between
old supernova remnants rather than within one. 相似文献