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191.
Krishna Teerth Chaturvedi Manjaree Pandit Laxmi Srivastava 《Applied Soft Computing》2009,9(3):962-969
The paper presents an effective evolutionary method for economic power dispatch. The idea is to allocate power demand to the on-line power generators in such a manner that the cost of operation is minimized. Conventional methods assume quadratic or piecewise quadratic cost curves of power generators but modern generating units have non-linearities which make this assumption inaccurate. Evolutionary optimization methods such as genetic algorithms (GA) and particle swarm optimization (PSO) are free from convexity assumptions and succeed in achieving near global solutions due to their excellent parallel search capability. But these methods usually tend to converge prematurely to a local minimum solution, particularly when the search space is irregular. To tackle this problem “crazy particles” are introduced and their velocities are randomized to maintain momentum in the search and avoid saturation. The performance of the PSO with crazy particles has been tested on two model test systems, compared with GA and classical PSO and found to be superior. 相似文献
192.
Mahulkar V. McKay S. Adams D.E. Chaturvedi A.R. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2009,39(6):1255-1270
Modeling and simulation environments are needed to support decision making in Navy Warfighters, which are emergent systems that pose a challenge to operations management. Ships consist of complex interconnected systems such as the infrastructure, crew, and workflow. A system-of-systems approach using agent-based modeling is applied here to develop workflow simulations involving a ship's crew conducting routine maintenance, watch duty, and reporting functions. Simple models are used to describe basic behavioral traits and intelligence in crew members; machinery including sensors for intelligent maintenance; equipment consuming power; mobile and stationary communication network access points; models for data transfer over the network; crew mobility models; power distribution and trimming models for the electrical system; and a fire model to simulate emergency scenarios. The simulation results demonstrate an increase in machine availability due to the implementation of intelligent maintenance systems. The effects of wireless-network usage on crew resource utilization and overall ship capability in normal operational scenarios are also demonstrated. A simple rescheduling algorithm is used to improve crew utilization and estimate manning requirements. The effects of emergency scenarios such as fires in different locations are also studied. Sensitivity analysis is presented to verify the developed model, and a note on validation is given. 相似文献
193.
Arya Deepika Bandyopadhyay Santanu 《Clean Technologies and Environmental Policy》2022,24(9):2681-2699
Clean Technologies and Environmental Policy - Process integration, which started its development in the early 1970s, is an emerging branch of study for conserving various resources. Process... 相似文献
194.
Causes of failure of the refractory lining of a cement rotary kiln are investigated for specimens taken from the preliminary firing and decarbonizing zone. It is established that at temperatures above 1400°C sodium-aluminum silicates are formed on the hot surface of the refractories and an increased content of alkali leads to the formation of compounds of the feldspar group.Translated from Ogneupory, No. 6, pp. 21–25, June, 1995. 相似文献
195.
The laser beam weld heat affected zone (HAZ) microstructure of a newly developed aerospace alloy, IC 6, was examined. HAZ microfissuring was observed and found to be associated with grain boundary liquation facilitated by subsolidus eutectic-type transformation of the alloy’s major phase, γ′ precipitates, and interfacial melting of M6C-type carbide and (Mo2Ni)B2-type boride particles. 相似文献
196.
Effect of natural flours on crystallization behaviors of poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) 下载免费PDF全文
This paper investigates the effects of natural flours on the crystallization behavior of poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) (PHBH). Two types of PHBH (3‐hydroxyhexanoate [3HH] contents of 5.6 and 11.1 mol %) were used as polymer matrix. One of two natural flours (cellulose or wood) at 1 wt % was added to this PHBH matrix. Crystallization behaviors under nonisothermal conditions were characterized using differential scanning calorimetry (DSC), while those under isothermal conditions were characterized using DSC and polarized optical microscopy. The results suggested that both cellulose and wood flour addition enhanced crystallization of the PHBH containing 5.6 mol % of 3HH (i.e., increased crystallization peak temperature and degree of crystallinity under the nonisothermal conditions, as well as decreased crystallization half time under the isothermal conditions). Of the two flours, wood flour was found to have greater effects, due to its higher crystal nucleating ability. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43600. 相似文献
197.
198.
Two families of distributions are considered that cover a large number of probability distributions useful in investigations involving reliability studies and survival analyses. The problem of bounded risk point estimation of the parameter and hazard rate function of the two families of distribution is handled. Motivated by Mukhopadhyay and Pepe (2006), Roughani and Mahmoudi (2015), and Mahmoudi and Lalehzari (2017), two-stage procedures are developed based on the maximum likelihood estimator (MLE) as well as uniformly minimum variance unbiased estimator (UMVUE). The estimation problem based on the minimum mean square estimator (MMSE) is also considered. We establish that the MMSE of the parameter and hazard rate provides a smaller risk. 相似文献
199.
S. Deepika 《Drying Technology》2018,36(14):1719-1737
The different pretreatments were given to lemon slices to inactivate pectinesterase and peroxidase enzymes and to dry the product rapidly using infrared–microwave hot air combination. Osmotic pretreatment followed by 1-min steam blanching was found to reduce moisture in the product, increase solid content, and inactivate enzymes in lemon slices while maintaining negligible dry matter and juice sac loss. The infrared hot air was found effective in partial drying of pretreated lemon slices up to 1 hour without entering in drastic falling-rate period. Therefore, after 1?h microwave hot air was used to complete the drying process. The optimum infrared drying condition was found at 3000?W/m2 radiation intensity, 90°C air temperature, 100?mm distance between lamp and product, and 1.5?m?s?1 air velocity. In microwave finish drying, the power density of 0.30?W?g?1, 89.9°C air temperature, and 0.5?m?s?1 air velocity were found to result in the best product. The hybridization of osmotic–steam blanching and the two drying methods overcame the problems of browning, extended falling-rate periods, improper power distribution, and quality deterioration. Also, the higher values of moisture diffusivities were observed during hybrid drying. 相似文献
200.