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In this paper we present a scale model for fitting an ideal shape to an object. The measurements of the object are taken corresponding to a fixed coordinate system at a set of well-defined locations on the surface of the object. We propose an algorithm to estimate the model parameters and hypothesis tests to make statistical inferences about several possible special cases of the general model. The model is tested with an example that analyzes data on the feet of people in Hong Kong. 相似文献
3.
Palangala S. Ravindra 《Information Systems Management》1987,4(1):74-75
More than just a regulatory body, the data administration group is responsible for planning and promoting the use of information resources. By managing the corporate data base effectively, data administration provides benefits to everyone who depends on the use of accurate information. 相似文献
4.
Ravindra Kumar Shirsendu Banerjee Anirban Banik Tarun Kanti Bandyopadhyay 《Petroleum Science and Technology》2017,35(6):615-624
The effect of diameter, velocity, and temperature on flow properties of heavy crude oil in three horizontal pipelines using computational fluid dynamics (CFD) was studied. The flow characteristics were simulated by using CFD software, ANSYS Fluent 6.2. The mesh geometry of the pipelines having inner diameter of 1, 1.5, and 2 inch were created by using Gambit 2.4.6. From grid independent study, 221, 365 mesh sizes were selected for simulation. The CFD ANSYS Fluent 6.2 Solver predicted the flow phenomena, pressure, pressure drop, wall shear stress, shear strain rate, and friction factor. A good agreement between experimental and CFD simulated values was obtained. 相似文献
5.
A. T. Fiory S. G. Chawda S. Madishetty V. R. Mehta N. M. Ravindra S. P. Mccoy M. E. Lefrançois K. K. Bourdelle J. M. Mckinley H. -J. L. Gossmann A. Agarwal 《Journal of Electronic Materials》2002,31(10):999-1003
Shallow junctions are formed in crystalline Si by low-energy ion implantation of B+, P+, or As+ species accompanied by electrical activation of dopants by rapid thermal annealing and the special case of spike annealing.
Diffusion depths were determined by secondary ion-mass spectroscopy (SIMS). Electrical activation was characterized by sheet
resistance, Hall coefficient, and reverse-bias diode-leakage measurements. The B+ and P+ species exhibit transient-enhanced diffusion (TED) caused by transient excess populations of Si interstitials. The electrically
activated fraction of implanted dopants depends mainly on the temperature for B+ species, while for P+ species, it depends on both temperature and P+ dose. The relatively small amount of diffusion associated with As+ implants is favorable for shallow-junction formation with spike annealing. 相似文献
6.
Ngo Quang Minh Khiem Guntur Ravindra Wei Tsang Ooi 《Signal Processing: Image Communication》2012,27(4):360-377
Zoomable video allows users to selectively zoom and pan into regions of interest within the video for viewing at higher resolutions. Such interaction requires dynamic cropping of RoIs on the source video. We have previously explored two different ways of encoding and transmitting video to support dynamic RoI cropping: (i) Monolithic streaming uses a standard video encoder to encode the video. When an RoI is requested, the bits belonging to the RoI along with other bits required to decode the RoIs (due to encoding dependencies) are transmitted. (ii) Tile streaming divides regions in the standard video into rectangular tiles that are encoded independently. The tiles that intersect with a requested RoI are transmitted. In this paper, we consider how the bandwidth needed to transmit the RoIs can be reduced by carefully encoding the source video for each of the two encoding schemes. The goal is to support bandwidth efficient compressed domain RoI cropping in the context of virtual zoom and pan by tuning encoder parameters. Our key idea is to exploit user access patterns to the RoIs, and encode different regions of the video with different encoding parameters based on the popularity of the region. We show that our encoding method can reduce the expected bandwidth by up to 43% in the test video sequence which we have used. 相似文献
7.
A valid damping of oscillations is an upcoming extensive challenge while maintaining the stability of the power system. This oscillation generally occurs due to the fluctuation raised, when two systems are interconnected. This paper addresses the oscillation occurred in the power system as the main challenge, which thus performs an effective simulation in 68-bus system. Here, it promotes a sufficient CC with two FACTS devices such as TCSC and UPFC, which are connected with PSS. Further, it adopts firefly algorithm to enable the CC among the FACTS devices. To the next of the simulation, this paper compares the performance of the FF- CC with conventional optimisations include GSO, PSO, GA and ABC algorithms to enable CC. Further, it provides a detailed analysis of the impact of PSS and loading effects on CC. As a result, the performance of FF-CC hands over the stable power system with powerful damping of oscillations, after comparing it with the existing methods.Abbreviations: ABC, Artificial Bee Colony; ICA, Imperialist Competitive Algorithm; AVR, Automatic Voltage Regulators; NETS, New England test system; BFOA, Bacteria Foraging Optimization Algorithm; NYPS, New York power system; BSO, Bacterial Swarm Optimization; PSO, Particle Swarm Optimization; CC, Coordinated Control; PSS, Power System Stabilizers; COA, Chaotic Optimization Algorithm; STATCOM, Static Synchronous Compensator; CS, Cuckoo Search; SSSC, Static Synchronous Series Compensator; FACTS, Flexible Alternating Current Transmission System; SVC, Static Var Compensator; GA, Genetic Algorithm; TCSC, Thyristor Controlled Series Capacitor; GSO, Gravitational Search Algorithm; UPFC, Unified Power Flow Controller 相似文献
8.
Data collected from operating plants can be mined to extract information related to both normal and fault modes of operation. Correspondence analysis (CA), that decomposes a measure of row–column association, to generate the lower dimensional space has been recently proposed [1] for this task. CA represents the association between samples and variables in terms of angle based measures on a biplot. Thus, toward clearer resolution of the faults, polar clustering and classification procedures are necessary. In this paper, we develop a methodology to mine the operating data and build such clusters. We demonstrate the application of this methodology on data generated from simulations and experiments involving representative systems,for detecting parametric changes and resolving sensor and actuator biases. 相似文献
9.
A generalized effectiveness factor equation (Eq. (32)), in terms of modified Bessel functions, is derived for a catalyst pellet of arbitrary shape. The derivation is based on utilizing an appropriate one-dimensional approximation for the Laplacian in an arbitrary shaped body subjected to a uniform external concentration field. The comparison of the result with the available expressions for various geometries is highly satisfactory. It unifies the expressions for the three fundamental shapes, viz., infinite slab, infinite cylinder and sphere, and also compares very well with the exact solutions for finite shapes over the entire range of the Thiele modulus. 相似文献
10.