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1.
2.
Many combinatorial optimization problems are solved by a sequence of network flow computations on a network whose edge capacities are given as a function of a parameter λ. Recently Galloet al. [7] made a major advance in solving such parametric flow problems. They showed that for an important class of networks, calledmonotone parametric flow networks, a sequence ofO(n) flow computations could be solved in the same worst-case time bound as a single flow. However, these results require one of two special assumptions: either that the λ values are presented in increasing or decreasing order; or that the edge capacity functions are affine functions of λ. In this paper we show how to remove both of these assumptions while obtaining the same running times as in [7]. This observation generalizes and unifies the two major results of [7], and allows its ideas to be applied to many new combinatorial problems. Of greatest importance, it allows the efficient application of binary search and successive binary search to a sequence of network flow problems. 相似文献
3.
A numerical model of solar cells is described, which provides optimum design rules for exponential N+ dopant profiles for heavily doped emitter regions. The model gives a useful insight into the relative impact of surface and bulk recombination on device performance. Results agree well with theorical models. 相似文献
4.
Marc Gravel Laszlo Kiss Jean-Marc Martel Wilson L. Price 《International Transactions in Operational Research》1994,1(3):363-373
This paper presents a decision support system designed to aid the production planner in choosing the values of the principle parameters governing just-in-time manufacturing. The DSS uses a knowledge base composed of data from simulations of the production of the entire product line under systematically varied conditions. The planners may add data from actual production experience as it is obtained. The stochastic dominance outranking method of Martel and Zaras allows the identification of clusters of parameters that respect the preferences of the decision maker. When launching an order for a product, the decision maker may judge certain sets of parameters to be equivalent. A visual interactive simulation model will then allow their comparison according to three performance criteria. 相似文献
5.
C Martel L Provencher X Li A St Pierre G Leblanc S Gauthier Y Mérand F Labrie 《Canadian Metallurgical Quarterly》1998,64(3-4):199-205
Tamoxifen (TAM), the only antiestrogen currently available for the endocrine therapy of breast cancer behaves as a mixed agonist/antagonist of estrogen action, thus limiting its therapeutic potential. We report the binding characteristics of a novel series of nonsteroidal antiestrogens to the rat uterine estrogen receptor. As measured by competition studies, the affinity of EM-652, the active metabolite of the prodrug EM-800, for the estrogen receptor is 7-11 times higher than that of 17beta-estradiol (E2), ICI 182780, and hydroxy-tamoxifen (OH-TAM), the active metabolite of Tamoxifen. EM-652 is 20x more potent than ICI 164384 and Droloxifene while it is 400 times more potent than Toremifene in displacing [3H]E2 from the rat uterine estrogen receptor. On the other hand, the prodrug EM-800 and Tamoxifen have respectively 150-fold and 410-fold less affinity for the estrogen receptor than the pure antiestrogen EM-652. No significant binding of EM-652, EM-800, TAM or OH-TAM was observed to the rat uterine progesterone receptor at concentrations up to 10,000 nM except for TAM that caused a 50% displacement of labeled R5020 at 4000 nM. No significant binding of EM-652 or EM-800 was observed on the rat ventral prostate androgen receptor or the rat uterine progesterone receptor. The present data demonstrate the high affinity and specificity of the new antiestrogen, EM-652, for the rat uterine estrogen receptor. The antiestrogen EM-652 thus becomes the compound having the highest known affinity for the estrogen receptor. Due to its unique potency and its pure antiestrogenic activity already demonstrated in many systems, this antiestrogen could well offer an important advance for the endocrine therapy of breast cancer, uterine cancer, and other estrogen-sensitive diseases in women. 相似文献
6.
Hormonal action controlling mammary activity 总被引:5,自引:0,他引:5
L M Houdebine J Djiane I Dusanter-Fourt P Martel P A Kelly E Devinoy J L Servely 《Journal of dairy science》1985,68(2):489-500
7.
Martel Zeldin Eric Granger Wilmer K. Fife 《Journal of Inorganic and Organometallic Polymers》1993,3(2):141-154
New silane monomers with the pendant 4-(3-pyridine)butyl group have been synthesized by hydrosilation of 3-(3-butenyl)pyridine with Me
n
Si(OEt)3-n
H (n=0, 1) using a platinum catalyst. Only -addition products were observed. The products were characterized by elemental analysis, infrared,1H- and13C-NMR spectroscopy, and gas chromatography-mass spectrometry. Hydrolysis-polycondensation of the difunctional monomer with a basic catalyst, Me4NOH, gave a mixture of cyclic oligomers, principally cyclic tetramer, and linear homopolymer. Under similar reaction conditions, the trifunctional monomer gave crosslinked material which was soluble in common organic solvents. The linear homopolymer and crosslinked polymer were trimethylsilyl end-blocked with hexamethyldisilazane. The cyclic and end-blocked polymers were characterized by elemental analysis and spectroscopic methods. Molecular weights of the polymers were obtained by end-group analysis using1H-NMR spectral data, size exclusion chromatography, and direct insertion-probe mass spectrometry. The cyclic, linear, and crosslinked materials were N-oxidized withm-chloroperoxybenzoic acid and characterized by spectroscopic methods. The polymeric N-oxide derivatives were shown to be effective transacylation catalysts in the synthesis of mixed carboxylic acid anhydrides in immiscible solvents (H2O/CH2Cl2) under phase-transfer conditions. The implications of the results on the mechanism of catalysis are discussed. 相似文献
8.
Kochanska Grazyna; Friesenborg Amanda E.; Lange Lindsey A.; Martel Michelle M. 《Canadian Metallurgical Quarterly》2004,86(5):744
The authors examined the contributions of infant's temperament and parent's personality to their relationship. In Study 1, 102 infants, mothers, and fathers were studied when infants were 7 months; in Study 2, 112 infants and mothers were followed from 9 to 45 months. Infants' temperament (joy, fear, anger, and attention) was observed in standard temperament paradigms. Parents' personality measures encompassed the Big Five traits and Empathy in Study 1 and Mistrust, Manipulativeness, Aggression, Dependency, Entitlement, and Workaholism in Study 2. Parent-child relationship (shared positive affect and parental responsiveness in Studies 1 and 2 and parental tracking of the infant in Study 1) was observed in naturalistic contexts. In Study 1, mothers' Neuroticism, Empathy, and Conscientiousness and fathers' Agreeableness, Openness, and Extraversion related to the relationship with the infants. All measures of infant temperament also related to the emerging relationship. In Study 2, maternal Mistrust, Manipulativeness, Dependency, and Workaholism predicted the relationship with the child. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Mohammed A?der Andrée-Anne Martel Joanny Ferracci Damien de Halleux 《Food and Bioprocess Technology》2012,5(8):3051-3065
The main objective of the present project was the purification of brown flaxseed meal from coloring pigments in order to improve its potential use as ingredient in food formulations. Thus, this work was aimed to study the bleaching of non-defatted brown flaxseed meal in dilute hydrogen peroxide solutions. Bleaching was evaluated according to the Hunter L, (a), and (b) color scale as function of the hydrogen peroxide concentration (1%, 2%, and 3% v/v), the meal concentration (2.5%, 5%, and 10% w/w), the bleaching time (10, 20, and 30?min), and the pH (3, 7, and 9). Effect of all the independent variables was significant. The L value was the most significantly affected parameter and increased as the concentration of hydrogen peroxide increased, but decreased as the concentration of flaxseed meal increased. The L value was observed to be higher at pH?9 than at pH?3 and 7. The b value, which represents the yellowness, was significantly increased from 18.70?±?0.01 (control sample) to 35.45?±?0.04 after the meal was treated with a 3% hydrogen peroxide solution at pH?9. Total phenolics content significantly decreased when the meal was treated with 3% (v/v) hydrogen peroxide solution. This concentration yielded the higher L color value (highly bleached meal). 相似文献
10.