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61.
Optimal operation of a multibasin reservoir system 总被引:1,自引:0,他引:1
A simulation-optimization procedure is presented for evaluating the extent of interbasin transfer of water in the Peninsular
Indian river system consisting of 15 reservoirs on four river basins. A system-dependent simulation model is developed incorporating
the concept of reservoir zoning to facilitate releases and transfers. The simulation model generates a larger number of solutions
which are then screened by the optimization model. The Box complex nonlinear programming algorithm is used for the optimization.
The performance of the system is evaluated through simulation with the optimal reservoir zones with respect to four indices,
reliability, resiliency, vulnerability and deficit ratio. The results indicate that by operating the system of 15 reservoirs
as a single unit the existing utilization of water may be increased significantly. 相似文献
62.
Esterling Brian A.; Antoni Michael H.; Kumar Mahendra; Schneiderman Neil 《Canadian Metallurgical Quarterly》1993,12(2):132
Investigated the relationship of individual differences in repressive coping styles with differences in antibody titer to Epstein-Barr (EB) viral capsid antigen in a normal, healthy college population made up of people previously exposed to EB. Each of 54 1st-yr undergraduates completed a battery of physical-status questions and items pertaining to potential behavioral immunomodulatory confounds, along with the Taylor Manifest Anxiety Scale and the Marlowe-Crowne Social Desirability Scale. Ss reporting high and middle levels of anxiety had higher antibody titers to EB, suggesting poorer immune control over the latent virus, as compared with the low-anxious group. Similarly, high-defensive Ss had higher antibody titers than their low-defensive counterparts, and neither group differed from the middle group. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
The present study was carried out to investigate the cardiovascular effects of centrally administered SRT6b in saline, BQ123 and BMS182874 pretreated male Sprague-Dawley rats, using a radioactive microsphere technique. SRT6b (100 ng, ICV) produced a transient increase (40%) in blood pressure at 5 min followed by a sustained decrease (-42%) at 30 and 60 min in control rats. Total peripheral resistance and heart rate were not significantly altered. Cardiac output increased (16%) at 5 min and decreased 30 and 60 min following SRT6b administration. Central venous pressure was not affected by SRT6b. Regional blood flow and vascular resistance did not change at 5 min following administration of SRT6b. However, a significant decrease in blood flow to the brain, heart, kidneys, liver, spleen, gastrointestinal tract and mesentery and pancreas was observed 30 and 60 min following administration of SRT6b in control (saline treated) rats. Pretreatment with ETA selective receptor antagonists, BQ123 (10 micrograms, ICV) or BMS182874 (50 micrograms, ICV) significantly attenuated the pressor and depressor effects of centrally administered SRT6b. SRT6b induced decrease in blood flow was completely blocked by pretreatment with BQ123 or BMS182874. ET-1 (100 ng, ICV) produced an increase followed by a decrease similar to SRT6b. Reserpine (5 mg/kg, IP) pretreatment attenuated the cardiovascular effects of ET-1. Role of sympathetic nervous system was determined by measuring splanchnic nerve activity. SRT6b when administered in the lateral cerebral ventricle did not produce any significant effect at 5 min, however, a significant decrease in sympathetic nerve activity was observed 30 min after its administration. It is concluded that centrally administered SRT6b produces significant changes in systematic and regional blood circulation which can be completely blocked by ETA receptor antagonist. The cardiovascular effects of centrally administered SRT6b appear to be mediated through the sympathetic nervous system. 相似文献
64.
Epidemiological studies have linked dietary fiber to the prevention of human colorectal cancer and suggest that short chain fatty acids such as butyric acid, which is produced by fermentation of dietary fiber in the large intestine, may be an important mediator of the protective effects of fiber. We investigated the role of Bcl-2 deregulation on the sensitivity of colorectal carcinoma cells to undergo butyrate-induced apoptosis. Here we report an inverse relationship between the levels of Bcl-2 and the sensitivity of colorectal carcinoma cell lines to undergo apoptosis in response to butyrate. Overexpression of Bcl-2 in colorectal carcinoma DiFi cells resulted in suppression of butyrate-induced apoptosis and enhanced cell survival in response to butyrate. Butyrate-induced apoptosis was accompanied by inhibition of expression of a 30 kDa protein (p30, immunorecognized by anti-Bcl-2 mAb) and this cellular effect of butyrate was inhibited by Bcl-2 overexpression. These findings suggest that deregulation of Bcl-2 in human colorectal carcinoma cells confers resistance to induction of apoptosis by butyrate, a dietary micronutrient. 相似文献
65.
66.
S. Kumar Author Vitae Author Vitae S. Ranganath Author Vitae Author Vitae F.T. Chew Author Vitae 《Pattern recognition》2006,39(6):1088-1098
This paper presents a robust rule-based approach for the splitting of binary clumps that are formed by objects of diverse shapes and sizes. First, the deepest boundary pixels, i.e., the concavity pixels in a clump, are detected using a fast and accurate scheme. Next, concavity-based rules are applied to generate the candidate split lines that join pairs of concavity pixels. A figure of merit is used to determine the best split line from the set of candidate lines. Experimental results show that the proposed approach is robust and accurate. 相似文献
67.
Several parameters and their limitations to prepare monodisperse polystyrene particles were discussed. Polystyrene latexes B, C and D of diameter 129.8, 142.8 and 264.5 nm, respectively, were synthesized by emulsion polymerization method. The latex D is almost monodisperse with very low polydispersity of 0.005 while B and C are having polydispersity of 0.1837 and 0.1601. The particle size and particle size distribution of the latexes were determined by a TEM and Brookhaven particle size analyzer. It was observed that the particle size of the latexes decreased with increasing initiator (ammonium persulfate) or surfactant (SDS) concentrations. The surface area of the latexes were calculated by using BET equation on the basis of the amount of nitrogen gas adsorbed at the surface of the particles to form a monolayer. It was observed that the surface area of latex D is less than B and C because of the bigger size of the particles. The average molecular weights, zeta potentials and densities of the latexes were also presented. 相似文献
68.
Basant Kumar Jha 《国际能源研究杂志》1992,16(1):85-88
An analytical study is performed to examine the thermal diffusion characteristics of free convection and mass transfer flow in a non-Newtonian fluid (Walters, 1962: liquid B') past a uniformly accelerated infinite vertical plate in the presence of thermal diffusion. The expression for the velocity field is obtained by the Laplace transform technique. The influence of the Soret number (a thermal diffusion parameter) on the velocity field is extensively discussed with the help of graphs. 相似文献
69.
R Kumar M Mandal A Lipton H Harvey CB Thompson 《Canadian Metallurgical Quarterly》1996,2(7):1215-1219
Overexpression of HER2 in estrogen receptor (ER)-positive human breast tumors has been associated with resistance to endocrine therapy. Here we investigated the effects of HER2 on expression of apoptotic pathways and modulation of tamoxifen-induced apoptosis in ER-positive MCF-7 breast cancer cells. We report that HER2 overexpression in MCF-7 cells is accompanied by up-regulation of antiapoptotic Bcl-2 and Bcl-XL proteins and suppression of tamoxifen-induced apoptosis. In addition, human tumor cell lines that are both ER positive and overexpress HER2 also express enhanced levels of Bcl-2 compared to cells that are either ER positive or overexpress HER2 alone. Our findings suggest that possible deregulation of antiapoptotic Bcl-2 and Bcl-XL may be associated with the enhanced survival of HER2-overexpressing and ER-positive breast cancer cells treated with antiestrogens. 相似文献
70.
Component commonality effects on inventory costs 总被引:5,自引:0,他引:5
In this paper we study the effects of increasing component commonality for a single-period model. A two-product, two-level configuration under a general component cost structure is considered. The economic implications of replacing different products' components by common components are analyzed. We develop optimal solutions for the Commonality and Non-Commonality (Basic) Models and provide bounds on the total savings resulting from using commonality. We demonstrate, under general and specific component cost structures, that some forms of commonality may not always be a preferred strategy. Furthermore, we present conditions under which commonality should not be used. Finally, an extension to the two-product multicomponent model is provided. 相似文献