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排序方式: 共有851条查询结果,搜索用时 171 毫秒
1.
Vedantham Ramachandran Reddy Edara Sreenivasa 《Multimedia Tools and Applications》2020,79(29-30):21487-21512
Multimedia Tools and Applications - Facial expression is the most common technique is used to convey the expressions of human beings. Due to different ethnicity and age, faces differ from one... 相似文献
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3.
Arjunan Arulchakkaravarthi Rakesh Kumar Parthasarathy Santhanaraghavan Sivaramakrishnan Muralithar Rengasamy Gopalakrishanan Perumalsamy Ramasamy 《Materials Research Innovations》2002,6(5-6):273-276
Organic molecular scintillating crystals are noted for their good timing and particle discrimination process. Trans-stilbene
is one such candidate noted for its good particle detection characteristics for the past five decades. Progressive strengthening
of detection characteristics of trans-stilbene has been attempted by improving crystal perfection. A series of timing resolution
studies have been carried out for the Bridgman grown trans-stilbene crystals under different experimental conditions. The
results were compared with the previously reported values. Pulse shape discrimination process has been carried out for 241Am and 252Cf sources and good discrimination has been obtained for gamma-alpha and gamma-neutron sources from the grown organic phosphor
crystal.
Electronic Publication 相似文献
4.
Long-period fibre gratings in specially designed birefringent few-mode fibres are used to demonstrate spectrally flat polarisers with bandwidths of 10 nm and polarisation extinction levels of 20 dB. This is enabled by the special dispersive properties of few-mode fibres, yielding fibre polarisers with performance approaching that of bulk-optic devices. 相似文献
5.
Lakshmi Ramachandran Nanjangud C. Narendra Karthikeyan Ponnalagu 《Service Oriented Computing and Applications》2012,6(4):283-302
Cloud-based systems promise an on-demand service provisioning system along with a ??pay-as-you-use?? policy. In the case of multi-tenant systems this would mean dynamic creation of a tenant by integrating existing cloud-based services on the fly. Presently, dynamic creation of a tenant is handled by building the required components from scratch. Although multi-tenant systems help providers save cost by allocating multiple tenants to the same instance of an application, they incur huge reconfiguration costs. Cost and time spent on these reconfiguration activities can be reduced by re-constructing tenants from existing tenant configurations supported by service providers. Multi-tenant cloud-based systems also lack the facility of allowing clients to specify their requirements. Giving clients the flexibility to specify requirements helps them avoid spending an excessive amount of time and effort looking through a list of services, many of which might not be relevant to them. Moreover, dynamic provisioning in the cloud requires an integrated solution across the technology stack (software, platform and infrastructure) combining functional, non-functional and resource allocation requirements. Existing research works in the area of web service matching, although numerous, still fall short, since they usually consider each requirement type in isolation and cannot provide an integrated solution. To that end, in this paper we investigate the features needed for dynamic service provisioning on the cloud. We propose a novel User Interface-Tenant Selector-Customizer (UTC) model and approach, which enables cloud-based services to be systematically modeled and provisioned as variants of existing service tenants in the cloud. Our approach considers functional, non-functional and resource allocation requirements, which are explicitly specified by the client via the user interface component of the model. To the best of our knowledge, ours is the first such integrated approach. We illustrate our ideas using a realistic running example, and also present a proof-of-concept prototype built using IBM??s Rational Software Architect modeling tool. We also present experimental results demonstrating the applicability of our matching algorithm. Our results show significant reduction in matching time with the help of an elimination process that reduces the search space needed for performing matching. 相似文献
6.
V. S. Ramachandran 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1972,22(11):1125-1138
The hydration characteristics of 3CaO.SiO2 or β2CaO.SiO2 are studied by an addition of 0.0, 0.1, 0.5 or 1.0% triethanolamine. The amount of Ca(OH)2 found at 1, 3, 7 or 28 days was in the order C3S + 0% TEA > C3S +0.1% TEA > C3S + 0.5% TEA > C3S+1.0% TEA, irrespective of whether lime was estimated by X-ray, DTA, TGA or chemical analysis. The rate of hydration, in terms of the disappearance of 3CaO.SiO2, showed that hydration proceeded faster in the presence of TEA after 1 day. Additions of TEA increase the induction period, promote the formation of a C-S-H with higher CaO/SiO2 ratio, increase the formation of non-crystalline Ca(OH)2 and enhance the surface area of the hydrated silicate product. 相似文献
7.
Mass transfer across gas and liquid boundary layers into the core of drops with liquid phase first order chemical reaction has been analyzed for spherical drops in the Reynolds number range of 50 < Reg < 400. The realistic and computationally efficient simulation of this gas absorption system is applicable in a variety of engineering fields including gas-liquid mass transfer in drops and sprays. The present paper deals with the fluid mechanics and mass transfer with chemical reaction of a single drop. In computer experiments good predictive agreement has been achieved with measured data. The theoretical results were generalized to show the influence of three major system parameters: Peclet number Peg or Pel Damköhler number Da and the distribution coefficient at the gas-liquid interface, M, on mass transfer and to demonstrate the importance of coupled gas- and liquid-phase resistances to gas absorption under practical conditions. 相似文献
8.
Temperature programmed desorption (TPD) and reduction (TPR) studies were carried out on H2S and thiophene adsorbed on Mo/Al2O3 and CoMo/Al2O3 catalysts. Freshly sulfided and pyridine poisoned catalysts were run. For sulfided catalysts, the major products of desorption of thiophene were thiophene and butene, leaving a carbonaceous residue. Subsequent TPR in H2 effected complete removal of the residue with formation of H2S, thiophene and butene. The residue appeared to consist of an easily reactive thiophene polymer and a less-reactive, sulfur-containing coke. Runs on poisoned catalysts showed less adsorption but product profiles were similar, showing that the adsorption characteristics of the remaining sites were not significantly altered. 相似文献
9.
Recognizing a subject given a set of biometrics is a fundamental pattern recognition problem. This paper builds novel statistical models for multibiometric systems using geometric and multinomial distributions. These models are generic as they are only based on the similarity scores produced by a recognition system. They predict the bounds on the range of indices within which a test subject is likely to be present in a sorted set of similarity scores. These bounds are then used in the multibiometric recognition system to predict a smaller subset of subjects from the database as probable candidates for a given test subject. Experimental results show that the proposed models enhance the recognition rate beyond the underlying matching algorithms for multiple face views, fingerprints, palm prints, irises and their combinations. 相似文献
10.
The problem of simultaneous absorption of two gases accompanied by reversible instantaneous chemical reactions is considered. Analytical equations are derived for the rates of absortion of the two gases. The solution is valid when the diffusivities of all species are assumed to be the same. The theoretical aspects of the problem of simultaneous absorption of hydrogen sulphide and carbon dioxide in amine solutions under equilibrium reaction conditions are also considered. 相似文献