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排序方式: 共有218条查询结果,搜索用时 15 毫秒
1.
UCINSKI DARIUSZ; JAI ABDELHAQ EL 《IMA Journal of Mathematical Control and Information》1997,14(2):153-174
In this paper, the concept of weak spreadability is introduced.It constitutes an extension of the idea developed by El Jai& Kassara. In the case of linear distributed systems weconsider quadratic control techniques with a conveniently penalizedcriterion which makes the system weakly spreadable. The approachis outlined for a convectiondiffusion system, and theresults of a numerical study are also included to illustratethe main features of the considered problem. 相似文献
2.
Bilevel programming approach applied to the flow shop scheduling problem under fuzziness 总被引:1,自引:0,他引:1
Samir A. Abass 《Computational Management Science》2005,2(4):279-293
This paper presents a fuzzy bilevel programming approach to solve the flow shop scheduling problem. The problem considered
here differs from the standard form in that operators are assigned to the machines and imposing a hierarchy of two decision
makers with fuzzy processing times. The shop owner considered higher level and assigns the jobs to the machines in order to
minimize the flow time while the customer is the lower level and decides on a job schedule in order to minimize the makespan.
In this paper, we use the concepts of tolerance membership function at each level to define a fuzzy decision model for generating
optimal (satisfactory) solution for bilevel flow shop scheduling problem. A solution algorithm for solving this problem is
given.
Mathematics Subject Classification:
90C70, 90B36, 90C99 相似文献
3.
4.
The solid–liquid equilibria of the ternary system H2O–Fe(NO3)3–Co(NO3)2 were studied by using a synthetic method based on conductivity measurements.
Two isotherms were established at 0 and 15 °C, and the stable solid phases which appear are the iron nitrate nonahydrate (Fe(NO3)3·9H2O), the iron nitrate hexahydrate (Fe(NO3)3·6H2O), the cobalt nitrate hexahydrate (Co(NO3)2·6H2O) and the cobalt nitrate trihydrate (Co(NO3)2·3H2O). 相似文献
5.
S. G. Yunusova S. D. Gusakova A. I. Glushenkova U. K. Nadzhimov Sh. Turabekov SA. Musaev 《Chemistry of Natural Compounds》1991,27(2):147-150
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991. 相似文献
6.
Mohamed Abass Hassan A. Allimony Heba Hassan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1799-1810
Abstract Oxidation of 3-acetyl-1-alkyl-4-hydroxyquinolin-2(1H)-ones using selenium dioxide under Riley conditions was described. The oxidation reaction produced a mixture of 2 unexpected α-keto acid and its dehydrated dimer derivatives. The oxidation reaction was studied under different reaction conditions in order to maximize the yields and optimize reaction conditions. Also, 1-alkyl-4-hydroxy-3-(2-nitroacetyl)quinolin-2(1H)-one and/or 3-acetyl-1-alkyl-4-diflouro-boryloxyquinolin-2(1H)-one derivatives were subjected to the same oxidation reaction giving rise improved reaction yields and selectivity in case of the boron-complex. Alkaline degradation of the dehydrated dimers led to formation of the 4-hydroxy-2-oxoquinoline-3-carboxylic acids while under the same conditions the α-keto acids underwent deoxalylation. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the following free supplemental files: Additional figures]. 相似文献
7.
Fiorin Lucio Pagès Gilles Sagna Abass 《Methodology and Computing in Applied Probability》2019,21(4):1087-1118
Methodology and Computing in Applied Probability - We introduce a new methodology for the quantization of the Euler scheme for a d-dimensional diffusion process. This method is based on a Markovian... 相似文献
8.
9.
Mohamed M. Hassan Elham S. Othman Mohamed Abass 《Research on Chemical Intermediates》2013,39(3):1209-1225
3-Acetyl-4-methylthioquinolin-2(1H)-one (3) has been prepared and its reactivity towards treatment with different reagents, dilute sulfuric acid, aqueous sodium hydroxide, and hydrogen peroxide, is described. The reactions of compound 3 with benzylamine, benzaldehyde, DMF-DMA, Vilsmeier-Haack reagent, 2-chloro-3-formyl-pyridopyrimidone and malononitrile have been carried out under convenient conditions. Compound 3 underwent heterocyclization reactions with some binucleophiles, hydrazine, hydroxylamine, urea, thiourea, semicarbazide, and thiosemicarbazide, furnishing some known five, six, and seven heterocyclic annellated quinolines. All the new compounds have been characterized using different spectral and analytical tools. 相似文献
10.
Mahrous Awad M. A. El-Desoky A. Ghallab Jan Kubes S. E. Abdel-Mawly Subhan Danish Disna Ratnasekera Mohammad Sohidul Islam Milan Skalicky Marian Brestic Alaa Baazeem Saqer S. Alotaibi Talha Javed Rubab Shabbir Shah Fahad Muhammad Habib ur Rahman Ayman EL Sabagh 《Molecules (Basel, Switzerland)》2021,26(11)
Accumulation of heavy metals (HMs) by ornamental plants (OPs) from contaminated agriculture soils is a unique technique that can efficiently reduce the metal load in the food chain. Amaranthus tricolor L. has attractive characteristics acquiring a higher growth rate and large biomass when grown at heavy metal contaminated soils. Site-specific detailed information is not available on the use of A. tricolor plant in metal phytoremediation from the polluted sites. The study aimed to enhance the uptake of HMs (Pb, Zn, and Cu) via amending poultry litter extract (PLE), vinasse sugarcane (VSC), and humic acid (HA) as natural mobilized organic materials compared to ethylene diamine tetraacetic acid (EDTA), as a common mobilized chemical agent by A. tricolor plant. The studied soils collected from Helwan, El-Gabal El-Asfar (Cairo Governorate), Arab El-Madabeg (Assiut Governorate), Egypt, and study have been conducted under pot condition. Our results revealed all organic materials in all studied soils, except EDTA in EL-Gabal El-Asfar soil, significantly increased the dry weight of the A. tricolor plant compared to the control treatment. The uptake of Pb and Zn significantly (p > 0.05) increased due to applying all organic materials to the studied soils. HA application caused the highest uptake as shown in Pb concentration by more than 5 times in Helwan soil and EDTA by 65% in El-Gabal El-Asfar soil while VSC increased it by 110% in El-Madabeg soil. Also, an increase in Zn concentration due to EDTA application was 58, 42, and 56% for Helwan, El-Gabal El-Asfar, and El-Madabeg soil, respectively. In all studied soils, the application of organic materials increased the remediation factor (RF) than the control. El-Madabeg soil treated with vinasse sugarcane gave the highest RF values; 6.40, 3.26, and 4.02% for Pb, Zn, and Cu, respectively, than the control. Thus, we identified A. tricolor as a successful ornamental candidate that, along with organic mobilization amendments, most efficiently develop soil health, reduce metal toxicity, and recommend remediation of heavy metal-contaminated soils. Additionally, long-term application of organic mobilization amendments and continued growth of A. tricolor under field conditions could be recommended for future directions to confirm the results. 相似文献