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排序方式: 共有2265条查询结果,搜索用时 15 毫秒
51.
Prince Prakash T. Srinivasa Kumar Shailesh Nayak 《International journal of remote sensing》2013,34(18):5789-5798
Daily chlorophyll-a concentration from the Ocean Colour Monitor (OCM) sensor onboard the Indian Remote Sensing satellite (IRS-P4) is used to make weekly and monthly chlorophyll-a concentration maps. The pathwise swath data at 12 noon for every alternate day over the north Indian Ocean (NIO) during February 2004 and February 2005 were used to compare the existing algorithms for binning the data. Atmospherically corrected and geocorrected OCM data were used in the comparative study of three averaging algorithms – arithmetic mean (AVG), geometric mean (GEO) and maximum likelihood estimator (MLE). The analysis shows that the AVG algorithm is best suited when compared with the two other algorithms. However, for case 1 water, MLE gives nearly the same value as AVG. Based on this result, AVG was selected for operational weekly and monthly averaging of OCM data over the NIO. These high-resolution-derived chlorophyll-a weekly and monthly products will be useful to resolve inter-annual-to-decadal changes in chlorophyll-a concentration over the NIO. 相似文献
52.
Sreeraj Gopi Augustine Amalraj Karthik Varma Shintu Jude Prakash B. Reddy Chandradhara Divya 《国际聚合物材料杂志》2018,67(9):581-588
A phytogenic feed additive (PFA) formulation was prepared with bioactive molecules—curcuminoids, gingerol, and carvacrol by encapsulating in nanofiber isolated from turmeric spent (turmeric nanofiber, TNF). This formulation was completely characterized by scanning electron microscope, ultra performance liquid chromatography, and gas chromatography and evaluated for its efficacy. PFA-encapsulated TNF (PFA@TNF) considerably increased mean body weight, decreased cholesterol level, mortality rate, and reduced Escherichia coli content of broilers than antibiotic growth promoter (AGP). The depth of crypts in the ileum of broilers was considerably reduced by the inclusion of PFA@TNF in diets compared with the AGP. 相似文献
53.
54.
S. Vinodh N. Hari Prakash K. Eazhil Selvan 《The International Journal of Advanced Manufacturing Technology》2011,57(1-4):343-352
The modern manufacturing organizations are adopting lean manufacturing principles so as to eliminate wastes and streamline their processes. The evaluation of leanness gains vital importance. Multiple tools/techniques are available for ensuring leanness. Due to the impreciseness and vagueness associated with decision-making problems, fuzzy logic need to be used. Relational databases enable decision-making process. This article presents a study in which fuzzy association rules mining approach has been used for leanness evaluation of an Indian modular switches manufacturing organization. The experiences gained as a result of the conduct of the study indicated that leanness evaluation could be performed by the decision makers without any constraints. 相似文献
55.
H.G. Raj Prakash Ganesh Sanjeev K.B. Vijay Kumar K. Siddappa B.K. Nayak A. Saxena 《Annals of Nuclear Energy》2011
Photofission cross-section of 232Th was measured using Bremsstrahlung radiation energy 7.4–9.2 MeV with energy step of 0.3 MeV by employing Lexan polycarbonate film as Solid State Nuclear Track Detectors (SSNTD). The photon intensity from the Microtron accelerator facility was estimated to be 1010 photons/s at a distance of 15 cm from the Bremsstrahlung converter using EGS-4 code (Nelson et al., 1985). Photofission cross-sections were evaluated using fission fragment angular distribution measurements. The present experimental results were compared with EMPIRE-2.19 (Herman et al., 2005) code prediction of RIPL-1 and RIPL-2 ( and ) and a new analytical formula (Gupta and Saxena, 2005) for fission barrier. 相似文献
56.
Gitanjaly Goyal Harpreet Singh Surindra Singh Satya Prakash 《Metallurgical and Materials Transactions A》2011,42(11):3269-3276
Inhibitors and oxide additives have been investigated with varying success to control high-temperature corrosion. Effect of
Y2O3 on high-temperature corrosion of Superni 718 and Superni 601 superalloys was investigated in the Na2SO4-60 pct V2O5 environment at 1173 K (900 °C) for 50 cycles. Y2O3 was applied as a coating on the surfaces of the specimens. Superni 601 was found to have better corrosion resistance in comparison
with Superni 718 in the Na2SO4-60 pct V2O5 environment. The Y2O3 superficial coating was successful in decreasing the reaction rate for both the superalloys. In the oxide scale of the alloy
Superni 601, Y and V were observed to coexist, thereby indicating the formation of a protective YVO4 phase. There was a distinct presence of a protective Cr2O3-rich layer just above the substrate/scale interface in the alloy. Whereas Cr2O3 was present with Fe and Ni in the scale of Superni 718. Y2O3 seemed to be contributing to better adhesion of the scale, as comparatively lesser spalling was noticed in the presence of
Y2O3. 相似文献
57.
Deo Prakash Vidyarthi Mohammad Anbar 《International Journal of Network Management》2011,21(2):120-129
Providing good quality of service (QoS) in cellular IP networks is an important requirement for performance improvement of the cellular IP network. Resource reservation is one of the methods used in achieving this goal and is proven to be effective. The main resources to be reserved in a cellular IP network are bandwidth, buffer and central processing unit (CPU) cycles. Router CPU cycle is the time taken by the router to process the packet of the flow before forwarding it to the next router (hop). This paper proposes a model for CPU cycle optimization of routers for real‐time flows in a cellular IP network. The model applies both genetic algorithm (GA) and particle swarm optimization (PSO) as soft computing tools to optimize the CPU cycles and reduces the flow processing time at each router in the route taken by a flow. Simulation experiments illustrate a comparative study of the model. 相似文献
58.
Arvind S. More Sharad K. Pasale Pandurang N. Honkhambe Prakash P. Wadgaonkar 《应用聚合物科学杂志》2011,121(6):3689-3695
Poly(ether ether ketone)s and poly(ether ether ketone ketone)s containing pendant pentadecyl chains were synthesized by polycondensation of each of the two bisphenol monomers viz, 1,1,1‐[bis(4‐hydroxyphenyl)‐4′‐pentadecylphenyl]ethane and 1,1‐bis(4‐hydroxyphenyl)‐3‐pentadecyl cyclohexane with activated aromatic dihalides namely, 4,4′‐difluorobenzophenone, and 1,3‐bis(4‐fluorobenzoyl)benzene in a solvent mixture of N,N‐dimethylacetamide and toluene, in the presence of anhydrous potassium carbonate. Polymers were isolated as white fibrous materials with inherent viscosities and number average molecular weights in the range 0.70–1.27 dL g?1 and 76,620–1,36,720, respectively. Poly(ether ether ketone)s and poly(ether ether ketone ketone)s were found to be soluble at room temperature in organic solvents such as chloroform, dichloromethane, tetrahydrofuran, and pyridine and could be cast into tough, transparent, and flexible films from their solutions in chloroform. Wide angle X‐ray diffraction patterns exhibited a broad halo at around 2θ = ~ 19° indicating that the polymers containing pentadecyl chains were amorphous in nature. In the small‐angle region, diffuse reflections of a typically layered structures resulting from the packing of pentadecyl side chains were observed. The temperature at 10% weight loss, obtained from TG curves, for poly(ether ether ketone)s and poly(ether ether ketone ketone)s were in the range 416–459°C, indicating their good thermal stability. A substantial drop in glass transition temperatures (68–78°C) was observed for poly(ether ether ketone)s and poly(ether ether ketone ketone)s due to “internal plasticization” effect of flexible pendant pentadecyl chains. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
59.
Wide‐Area Strain Sensors based upon Graphene‐Polymer Composite Coatings Probed by Raman Spectroscopy 下载免费PDF全文
Arun Prakash Aranga Raju Amanda Lewis Brian Derby Robert J. Young Ian A. Kinloch Recep Zan Kostya S. Novoselov 《Advanced functional materials》2014,24(19):2865-2874
Functional graphene optical sensors are now viable due to the recent developments in hand‐held Raman spectroscopy and the chemical vapor deposition (CVD) of graphene films. Herein, the strain in graphene/poly (methyl methacrylate) sensor coatings is followed using Raman band shifts. The performance of an “ideal” mechanically‐exfoliated single crystal graphene flake is compared to a scalable CVD graphene film. The dry‐transferred mechanically exfoliated sample has no residual stresses, whereas the CVD sample is in compression following the solvent evaporation during its transfer. The behavior of the sensors under cyclic deformation shows an initial breakdown of the graphene‐polymer interface with the interface then stabilizing after several cycles. The Raman 2D band shift rates per unit strain of the exfoliated graphene are ≈35% higher than CVD graphene making the former more strain sensitive. However, for practical wide‐area applications, CVD graphene coatings are still viable candidates as a Raman system can be used to read the strain in any 5 μm diameter spot in the coating to an absolute accuracy of ≈0.01% strain and resolution of ≈27 microstrains (μs), which compares favorably to commercial photoelastic systems. 相似文献
60.
K. Hariharan F. Barlat M. G. Lee R. V. Prakash 《Fatigue & Fracture of Engineering Materials & Structures》2014,37(9):977-991
The fatigue strain–life equation is in general applicable to isotropic materials. It was recently attempted to account for material anisotropy because of crystallographic texture in fatigue modelling. The proposed modification was limited to isotropic hardening. The present work is an extension of the previous work, wherein a general framework to model anisotropy using phenomenological yield criterion and anisotropic hardening is provided. Yld2004‐18p yield criterion and the so‐called homogenous anisotropic hardening model are used to demonstrate the anisotropic cyclic behaviour of low carbon steel. The proposed methodology can be utilized in applications including multiaxial fatigue modelling. 相似文献