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排序方式: 共有341条查询结果,搜索用时 15 毫秒
101.
Nitin Anand Shrivastava Bijaya Ketan Panigrahi Meng-Hiot Lim 《Neural computing & applications》2016,27(1):9-18
Forecasting electricity prices has been a widely investigated research issue in the deregulated power market scenario. High price volatilities, price spikes caused by a number of factors such as weather uncertainty, fluctuating fuel prices, transmission bottlenecks, etc., make the task of accurate price forecasting a formidable challenge for the market participants. A number of models have been proposed by researchers; however, achieving high accuracy is always not possible. In some specific applications such as self-scheduling by demand side participants, certain price thresholds are more useful than accurate price forecasts. In this paper, we have investigated the application of a novel neural network-based technique called extreme learning machine for the problem of classification of future electricity prices with respect to certain price thresholds. Different models corresponding to different lead times are developed and tested with data corresponding to Ontario and PJM markets. It is observed that classification with ELM is fast, less sensitive to user defined parameters and easily implementable. 相似文献
102.
Girjesh Singh S. B. Shrivastava Deepti Jain Swati Pandya T. Shripathi V. Ganesan 《Bulletin of Materials Science》2010,33(5):581-587
We report the conducting and transparent In doped ZnO films fabricated by a homemade chemical spray pyrolysis system (CSPT).
The effect of In concentration on the structural, morphological, electrical and optical properties have been studied. These
films are found to show (0 0 2) preferential growth at low indium concentrations. An increase in In concentration causes a
decrease in crystalline quality of films as confirmed by X-ray diffraction technique which leads to the introduction of defects
in ZnO. Indium doping also significantly increased the electron concentrations, making the films heavily n type. However, the crystallinity and surface roughness of the films decreases with increase in indium doping content likely
as a result of the formation of smaller grain size, which is clearly displayed in AFM images. Typical optical transmittance
values in the order of (80%) were obtained for all films. The lowest resistivity value of 0.045 Ω-m was obtained for film
with 5% indium doping. 相似文献
103.
Kistijantoro Achmad I. Morgan Graham Shrivastava Santosh K. Little Mark C. 《IEEE transactions on pattern analysis and machine intelligence》2008,34(4):531-545
Three-tier middleware architecture is commonly used for hosting enterprise distributed applications. Typically the application is decomposed into three layers: front-end, middle tier and back-end. Front-end ('Web server') is responsible for handling user interactions and acts as a client of the middle tier, while back-end provides storage facilities for applications. Middle tier ('Application server') is usually the place where all computations are performed. The benefit of this architecture is that it allows flexible management of a cluster of computers for performance and scalability; further, availability measures, such as replication, can be introduced in each tier in an application specific manner. However, incorporation of availability measures in a multi-tier system poses challenging system design problems of integrating open, non proprietary solutions to transparent failover, exactly once execution of client requests, non-blocking transaction processing and an ability to work with clusters. This paper describes how replication for availability can be incorporated within the middle and back-end tiers meeting all these challenges. The paper develops an approach that requires enhancements to the middle tier only for supporting replication of both the middleware backend tiers. The design, implementation and performance evaluation of such a middle are presented. 相似文献
104.
Widespread usage of electronic equipment and shortened product life cycles have challenged original equipment manufacturers (OEMs) to handle End-Of-Life (EOL) product through environmentally benign reverse manufacturing and reusable resources recovery. This paper presents a web-based decision support and evaluation system for operations in remanufacturing and recycling including electronic product disassembly, materials recovery, and recycling management. An overall evaluation of the product's lifecycle environmental impact considering EOL dispositions is also provided. The system has been tested by a major computer manufacturer with computer systems including desktop, laptop, and server. Comprehensive product analysis and environmental impact assessment are discussed in the paper. 相似文献
105.
Although it has long been realized that ACID (atomicity, consistency, isolation, durability) transactions by themselves are not adequate for structuring long‐lived applications and much research work has been done on developing specific extended transaction models, no middleware support for building extended transactions is currently available and the situation remains that a programmer often has to develop application specific mechanisms. The CORBA Activity Service Framework described in this paper is a way out of this situation. The design of the service is based on the insight that the various extended transaction models can be supported by providing a general purpose event signalling mechanism that can be programmed to enable activities—application specific units of computations—to coordinate each other in a manner prescribed by the model under consideration. The different extended transaction models can be mapped onto specific implementations of this framework, permitting such transactions to span a network of systems connected indirectly by some distribution infrastructure. The framework described in this paper is an overview of the OMG's (Object Management Group) Additional Structuring Mechanisms for the OTS standard. Through a number of examples the paper shows that the framework has the flexibility to support a wide variety of extended transaction models. Although the framework is presented here in CORBA specific terms, the main ideas are sufficiently general, so that it should be possible to use them in conjunction with other middleware. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
106.
Vinod K. Wadhawan Pragya Pandit Surya M. Gupta 《Materials Science and Engineering: B》2005,120(1-3):199-205
The basic classification of smart materials and structures is reviewed briefly. The role of nonlinear response for achieving field-tunability of properties is described in simple terms. The observation of the two-way shape-memory effect in a solid solution of lead magnesium niobate (PMN) and lead titanate (PT) for the nominal atomic composition 65:35 is reported. Possible factors influencing the occurrence of the two-way effect are discussed. It is argued that such relaxor ferroelectric ceramics can function as smart materials (rather than serving merely as components of smart structures), because they can meet the “information-reduction” criterion. And they qualify to be called very smart because they have a fairly large number of smartness attributes, including the two-way shape-memory attribute reported here. 相似文献
107.
A family of trusted third party based fair-exchange protocols 总被引:1,自引:0,他引:1
Ezhilchelvan P.D. Shrivastava S.K. 《Dependable and Secure Computing, IEEE Transactions on》2005,2(4):273-286
Fair exchange protocols play an important role in application areas such as e-commerce where protocol participants require mutual guarantees that a transaction involving exchange of items has taken place in a specific manner. A protocol is fair if no protocol participant can gain any advantage over an honest participant by misbehaving. In addition, such a protocol is fault-tolerant if the protocol can ensure that an honest participant does not suffer any loss of fairness despite any failures of the participant's node. This paper presents a family of fair exchange protocols for two participants which make use of the presence of a trusted third party, under a variety of assumptions concerning participant misbehavior, message, delays, and node reliability. The development is systematic, beginning with the strongest set of the assumptions and gradually weakening the assumptions to the weakest set. The resulting protocol family exposes the impact of a given set of assumptions on solving the problem of fair exchange. Specifically, it highlights the relationships that exist between fairness and assumptions on the nature of participant misbehavior, communication delays, and node crashes. The paper also shows that the restrictions assumed on a dishonest participant's misbehavior can be realized through the use of smartcards and smartcard-based protocols. 相似文献
108.
109.
Monika Gupta Vidhika Sharma Jaya Shrivastava Anjana Solanki A. P. Singh V. R. Satsangi S. Dass Rohit Shrivastav 《Bulletin of Materials Science》2009,32(1):23-30
Nanostructured zinc oxide thin films (ZnO) were prepared on conducting glass support (SnO2: F overlayer) via sol-gel starting from colloidal solution of zinc acetate 2-hydrate in ethanol and 2-methoxy ethanol. Films
were obtained by spin coating at 1500 rpm under room conditions (temperature, 28–35°C) and were subsequently sintered in air
at three different temperatures (400, 500 and 600°C). The evolution of oxide coatings under thermal treatment was studied
by glancing incidence X-ray diffraction and scanning electron microscopy. Average particle size, resistivity and bandgap energy
were also determined. Photoelectrochemical properties of thin films and their suitability for splitting of water were investigated.
Study suggests that thin films of ZnO, sintered at 600°C are better for photoconversion than the films sintered at 400 or
500°C. Plausible explanations have been provided. 相似文献
110.
A distinct strategy to generate high-affinity peptide binders to receptor tyrosine kinases 总被引:1,自引:0,他引:1
Shrivastava A von Wronski MA Sato AK Dransfield DT Sexton D Bogdan N Pillai R Nanjappan P Song B Marinelli E DeOliveira D Luneau C Devlin M Muruganandam A Abujoub A Connelly G Wu QL Conley G Chang Q Tweedle MF Ladner RC Swenson RE Nunn AD 《Protein engineering, design & selection : PEDS》2005,18(9):417-424
We describe a novel and general way of generating high affinity peptide (HAP) binders to receptor tyrosine kinases (RTKs), using a multi-step process comprising phage-display selection, identification of peptide pairs suitable for hetero-dimerization (non-competitive and synergistic) and chemical synthesis of heterodimers. Using this strategy, we generated HAPs with K(D)s below 1 nM for VEGF receptor-2 (VEGFR-2) and c-Met. VEGFR-2 HAPs bound significantly better (6- to 500-fold) than either of the individual peptides that were used for heterodimer synthesis. Most significantly, HAPs were much better (150- to 800-fold) competitors than monomers of the natural ligand (VEGF) in various competitive binding and functional assays. In addition, we also found the binding of HAPs to be less sensitive to serum than their component peptides. We believe that this method may be applied to any protein for generating high affinity peptide (HAP) binders. 相似文献