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Sirisha Nerella Debendra K. Das Godwin A. Chukwu Abhijit Y. Dandekar Santanu Khataniar Shirish L. Patil 《Petroleum Science and Technology》2003,21(7):1275-1294
Gas-to-liquids (GTL) technology involves the conversion of natural gas to liquid hydrocarbons. In this article, theoretical studies have been presented to determine the feasibility of transporting GTL products through the Trans-Alaska Pipeline System (TAPS). To successfully transport GTL through TAPS, heat loss along the route must be carefully determined. This study presents heat transfer and fluid dynamic calculations to evaluate this feasibility. Because of heat loss, the fluid temperature decreases in the direction of flow and this affects the fluid properties, which in turn influence convection coefficient and pumping power requirements. The temperature and heat loss distribution along the pipeline at different locations have been calculated. Fairly good agreement with measured oil temperatures is observed. The powers required to pump crude oil and GTL individually, against various losses have been calculated. Two GTL transportation modes have been considered; one as a pure stream of GTL and the second as a commingled mixture with crude oil. These results show that the pumping power and heat loss for GTL are less than that of the crude oil for the same volumetric flow rate. Therefore, GTL can be transported through TAPS using existing equipment at pump stations. 相似文献
23.
Finite sample properties of estimators of spatial autoregressive models with autoregressive disturbances 总被引:1,自引:0,他引:1
The article investigates the finite sample properties of estimators for spatial autoregressive models where the disturbance
terms may follow a spatial autoregressive process. In particular we investigate the finite sample behavior of the feasible
generalized spatial two-stage least squares (FGS2SLS) estimator introduced by Kelejian and Prucha (1998), the maximum likelihood
(ML) estimator, as well as that of several other estimators. We find that the FGS2SLS estimator is virtually as efficient
as the ML estimator. This is important because the ML estimator is computationally burdensome, and may even be forbidding
in large samples, while the FGS2SLS estimator remains computationally feasible in large samples.
Received: 20 January 2001 / Accepted: 31 August 2001 相似文献
24.
Perceptual Temporal Quality Metric for Compressed Video 总被引:2,自引:0,他引:2
Kai-Chieh Yang Guest C.C. El-Maleh K. Das P.K. 《Multimedia, IEEE Transactions on》2007,9(7):1528-1535
This paper presents a metric to quantify frame loss according to the impact on perceived temporal quality. This metric particularly aims at measuring the temporal quality degradation caused by both regular and irregular frame loss. Experimental results with subjective viewing demonstrate high performance on prediction of perceptual temporal quality. 相似文献
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Quantitation of Cefaclor in Pharmaceutical Dosage Forms Using High Performance Liquid Chromatography
Mary Mathew V. Das Gupta Charlie Bethea 《Drug development and industrial pharmacy》1993,19(14):1723-1729
A stability-indicating high-performance liquid chromatography for the quantitation of cefaclor in pharmaceutical dosage forms has been developed. The method is accurate and precise with a percent relative standard deviation of 1.2 based on 5 readings. A number of inactive ingredients present in the capsules and suspensions did not interfere with the assay procedure. The extraction procedure from the dosage forms is very simple. The recovery from the synthetic mixtures was quantitative. The capsules which had expired 3 years ago lost only 3% of the potency. The drug appears to be very sensitive to strong acids or bases since a 5 minute boiling caused 100% degradation of drug in both the solutions. 相似文献
29.
Reconstruction of an original continuous curve and the estimation of its parameters from the digitized version of the curve
is a challenging problem, as quantization always causes some loss of information. In this paper, we have developed a scheme
for reconstruction which is applicable to a class of curves having at the most two parameters. The class of curves for which
the scheme works has also been characterized. We have shown that for one-parameter curves the exact domain of values of the
parameter can be obtained. But in the two-parameter case, only the smallest rectangle containing the domain can be realised.
The distinctive feature of our scheme is that it provides a unified approach to solve the reconstruction and the domain-finding
problem for a class of curves. 相似文献
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