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21.
Performance of Recalibrated Equations for the Estimation of Daily Reference Evapotranspiration 总被引:1,自引:0,他引:1
P. Mallikarjuna S. Aruna Jyothy D. Srinivasa Murthy K. Chandrasekhar Reddy 《Water Resources Management》2014,28(13):4513-4535
An accurate estimation of reference evapotranspiration (ET0) is of paramount importance for many studies such as hydrologic water balance, irrigation system design and management, crop yield simulation, and water resources planning and management. In the present study, Blaney-Criddle, Jensen-Haise and Hargreaves (temperature based), Priestley-Taylor, Radiation and Makkink (radiation based) and, Pan Evaporation and Christiansen (pan evaporation based) methods have been evaluated and recalibrated with respect to FAO-56 Penman-Monteith method for estimating daily ET0 in the semi-arid Tirupati, Nellore, Rajahmundry, Anakapalli and Rajendranagar sites of Andhra Pradesh, India. Recalibrated Blaney-Criddle (temperature based), Radiation (Radiation based) and Christiansen (Pan evaporation based) methods showed a satisfactory performance at the sites. Further, recalibrated Blaney- Criddle method showed relatively better performance than Radiation and Christiansen methods in the daily ET0 estimation. Recalibrated Blaney- Criddle method may therefore be adopted at the sites selected for the present study and also at the sites with similar climatic conditions for satisfactory daily ET0 estimation. 相似文献
22.
Chakrabarti Saikat Chandrasekhar Santosh Singhal Mukesh Calvert Kenneth L. 《Parallel and Distributed Systems, IEEE Transactions on》2009,20(7):1059-1072
Aggregate signatures can be a crucial building block for providing scalable authentication of a large number of users in several applications like building efficient certificate chains, authenticating distributed content management systems, and securing path vector routing protocols. Aggregate signatures aim to prevent resources (signature and storage elements, and computation) from growing linearly in the number of signers participating in a network protocol. In this paper, we present an efficient and scalable quasi-aggregate signature scheme, {rm CLFSR}- {rm QA}, based on third-order linear feedback shift register (cubic LFSR) sequences that can be instantiated using both XTR and GH public key cryptosystems. In the proposed {rm CLFSR}-{rm QA} construction, signers sign messages sequentially; however, the verfier need not know the order in which messages were signed. The proposed scheme offers constant length signatures, fast signing, aggregation, and verification operations at each node, and requires the least storage elements (public keys needed to verify the signature), compared to any other aggregate signature scheme. To the best of our knowledge, {rm CLFSR}- {rm QA} is the first aggregate signature scheme to be constructed using LFSR sequences. We believe that the {rm CLFSR}- {rm QA} signature scheme can be catalytic in improving the processing latency as well as reducing space requirements in building secure, large-scale distributed network protocols. We perform extensive theoretical analysis including correctness and security of {rm CLFSR}- {rm QA} and also present a performance (computation and communication costs, storage overhead) comparison of the proposed scheme with well-known traditional constructions. 相似文献
23.
Bernasconi P. Yang W. Zhang L. Sauer N. Buhl L. Kang I. Chandrasekhar S. Neilson D.T. 《Electronics letters》2005,41(12):701-702
An all-optical wavelength-switch module with 40 Gbit/s capacity is integrated monolithically in InP. The device combines an SOA-based wavelength converter and a fast-tunable 8-channel multi-frequency laser. Error-free operation is demonstrated. 相似文献
24.
An effort is made to study the anti-thrombogenic property of the latex of fig tree by immobilizing its components on nylon
surface. It is also evaluated, how such surfaces may effect the blood compatibility by investigating variations in surface
energy parameters, plasma recalcification time and platelet adhesion using calf’s blood. 相似文献
25.
26.
Anindita Bhadra Aniruddha Mitra Sujata A. Deshpande Kannepalli Chandrasekhar Dattatraya G. Naik Abraham Hefetz Raghavendra Gadagkar 《Journal of chemical ecology》2010,36(4):424-431
Queens and workers are not morphologically differentiated in the primitively eusocial wasp, Ropalidia marginata. Upon removal of the queen, one of the workers becomes extremely aggressive, but immediately drops her aggression if the
queen is returned. If the queen is not returned, this hyper-aggressive individual, the potential queen (PQ), will develop
her ovaries, lose her hyper-aggression, and become the next colony queen. Because of the non-aggressive nature of the queen,
and because the PQ loses her aggression by the time she starts laying eggs, we hypothesized that regulation of worker reproduction
in R. marginata is mediated by pheromones rather than by physical aggression. Based on the immediate loss of aggression by the PQ upon return
of the queen, we developed a bioassay to test whether the queen’s Dufour’s gland is, at least, one of the sources of the queen
pheromone. Macerates of the queen’s Dufour’s gland, but not that of the worker’s Dufour’s gland, mimic the queen in making
the PQ decrease her aggression. We also correctly distinguished queens and workers of R. marginata nests by a discriminant function analysis based on the chemical composition of their respective Dufour’s glands. 相似文献
27.
Venkatasubbaiah Krishnan Ravindranathan Bindu Vadapalli Chandrasekhar Varanasi S. R. Murthy 《Journal of the American Ceramic Society》2002,85(2):504-506
A new method for chemically cross-linking polysilastyrene using divinylbenzene as the cross-linking agent is reported. The procedure involves a single-step synthesis using the alkali-metal sodium to promote the polymerization of dimethyldichlorsilane in the presence of the comonomers phenylmethyldichlorosilane and divinylbenzene. The cross-linked polymer can be readily converted to β-SiC on pyrolysis at 1500°C. The β-SiC obtained by this procedure is nanocrystalline and has a grain-size distribution of 8–20 nm. 相似文献
28.
Garrett L.D. Chandrasekhar S. Zyskind J.L. Sulhoff J.W. Dentai A.G. Burrus C.A. Lunardi L.M. Derosier R.M. 《Lightwave Technology, Journal of》1997,15(5):827-832
The performance of an eight-channel, 2.5 Gb/s OEIC photoreceiver array in an eight-wavelength long-distance WDM testbed is described. The sensitivity penalties due to crosstalk and transmission are measured, and the source of crosstalk is investigated. Channel sensitivities range from -25.4 to -26.2 dBm after transmission through 720 km of standard fiber, with transmission penalties ranging from 0.3 dB to 1.0 dB. When the power in each of seven interfering channels is 5 dB above sensitivity, the maximum crosstalk penalty suffered by an individual channel does not exceed 1 dB. These experiments are the first comprehensive characterization of monolithic receiver arrays for crosstalk performance under multichannel operation in a realistic system environment 相似文献
29.
Raybon G. Koren U. Miller B.I. Chien M. Dreyer K. Chandrasekhar S. Behringer R.E. Tennant D.M. Feder K. 《Photonics Technology Letters, IEEE》1998,10(2):215-217
Reconfigurable optoelectronic wavelength conversion to 11 100-GHz spaced wavelengths is achieved using a wavelength selectable laser array with an integrated electroabsorption (EA) modulator at a bit rate of 2.5 Gb/s. Wide dynamic range at the input from -24.2 to -6.5 dBm is achieved and uniform back-to-back transmission performance is measured for all wavelengths 相似文献
30.
We demonstrate the information on molecular vibrational modes via the second derivative (d(2)I(B)/dV(2)) of the ballistic electron emission spectroscopy (BEES) current. The proposed method does not create huge fields as in the case of conventional derivative spectroscopy and maintains a zero bias across the device. BEES studies carried out on three different types of large polycyclic aromatic hydrocarbon (PAH) molecular layers show that the d(2)I(B)/dV(2) spectra consist of uniformly spaced peaks corresponding to vibronic excitations. The peak spacing is found to be identical for molecules within the same PAH family though the BEES onset voltage varies for different molecules. In addition, injection into a particular orbital appears to correspond to a specific vibrational mode as the manifestation of the symmetry principle. 相似文献