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1.
Farsi R. Mohammadi M. K. Saghanezhad S. J. 《Russian Journal of Organic Chemistry》2021,57(12):2002-2009
Russian Journal of Organic Chemistry - Herein, we report the sulfonamide-functionalized covalent organic framework (COF-SO3H), prepared by condensation of melamine and terephthalaldehyde and... 相似文献
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3.
Hadi Mohammadi Bidhandi 《Annals of Operations Research》2006,143(1):237-250
This paper develops a mathematical model for project time compression problems in CPM/PERT type networks. It is noted this
formulation of the problem will be an adequate approximation for solving the time compression problem with any continuous
and non-increasing time-cost curve. The kind of this model is Mixed Integer Linear Program (MILP) with zero-one variables,
and the Benders' decomposition procedure for analyzing this model has been developed. Then this paper proposes a new approach
based on the surrogating method for solving these problems. In addition, the required computer programs have been prepared
by the author to execute the algorithm. An illustrative example solved by the new algorithm, and two methods are compared
by several numerical examples. Computational experience with these data shows the superiority of the new approach. 相似文献
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B. Ivorra A. M. Ramos B. Mohammadi 《Journal of Optimization Theory and Applications》2007,135(3):549-561
This paper has two objectives. We introduce a new global optimization algorithm reformulating optimization problems in terms
of boundary-value problems. Then, we apply this algorithm to a pointwise control problem of the viscous Burgers equation,
where the control weight coefficient is progressively decreased. The results are compared with those obtained with a genetic
algorithm and an LM-BFGS algorithm in order to check the efficiency of our method and the necessity of using global optimization
techniques. 相似文献
6.
Normative KGP agents 总被引:1,自引:0,他引:1
Fariba Sadri Kostas Stathis Francesca Toni 《Computational & Mathematical Organization Theory》2006,12(2-3):101-126
We extend the logical model of agency known as the KGP model, to support agents with normative concepts, based on the roles
an agent plays and the obligations and prohibitions that result from playing these roles. The proposed framework illustrates
how the resulting normative concepts, including the roles, can evolve dynamically during the lifetime of the agent. Furthermore,
we illustrate how these concepts can be combined with the existing capabilities of KGP agents in order to plan for their goals,
react to changes in the environment, and interact with other agents. Our approach gives an executable specification of normative
concepts that can be used directly for prototyping applications.
Fariba Sadri is a senior lecturer at Imperial College London, from where she received her PhD. Her earlier work concentrated on integrity
of deductive databases and temporal reasoning, in particular using the event calculus. In more recent years her work has been
on agent technologies and multi-agent systems. She has worked on logic-based agent models, reasoning, dynamic belief revision,
and inter-agent communication and negotiation for resources. She was co-awarded an EPSRC grant for research into logic-based
multi-agents and was co-investigator in the EU SOCS project.
Kostas Stathis is a senior lecturer at Royal Holloway, University of London and he holds a PhD from Imperial College London. His research
interests are in the area of computational intelligence in general and in the intersection of computational logic and cognitive
systems for social computing applications in particular. His research interests include: representation of human-computer
(or computer-computer) interaction as a game; cognitive & autonomous agents; artificial agent societies; agent communication;
programmable agents and agent platforms. He is a co-investigator of the EU ArguGRID project and was a co-investigator of the
EU SOCS project.
Francesca Toni is a senior lecturer at Imperial College London, from where she received her PhD. Her earlier work focused on abductive reasoning.
In more recent years, she focused on argumentation, agent models and multi-agent systems. She has worked on computational
logic-based agent models, agent reasoning, dynamic belief revision, and inter-agent communication and negotiation for resources.
She has been co-ordinator of the EU SOCS project, which developed the KGP model of agency, and is coordinator of the EU ArguGRID
project, on the application of argumentative agents within grid systems. 相似文献
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8.
A novel sensitive and simple method for rapid and selective extraction, preconcentration and determination of iron (as its
bathophenanthroline complex) and copper (as its neocuproine complex) using octadecyl silica cartridges and dual wavelength
spectrophotometry is presented. The dual wavelength method (533 nm for the iron-bathophenanthroline and 454 nm for the copper-neocuproine
as the analytical wavelength) is used to eliminate spectral interferences. Extraction efficiency and the influence of flow
rates of sample solution and eluent, pH, amount of neocuproine, bathophenanthroline and hydroxylamine hydrochloride, type
and least amount of eluent for elution of iron and copper complexes from cartridge, break-through volume and limit of detection
are evaluated. The effects of various cationic and anionic interferences on percent recovery of iron and copper are also studied.
Extraction efficiencies >95% are obtained by elution of cartridges with minimal amount of organic solvent. Iron and copper
were determined in the range of 3–100 ng mL−1. The limits of detection are 0.98 and 1.13 ng mL−1 for iron and copper, respectively. The proposed method is applied successfully to the determination of both analytes in river,
tap and well water samples.
Author for correspondence. E-mail: yyamini@modares.ac.ir
Received September 18, 2002; accepted December 12, 2002
Published online May 5, 2003 相似文献
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10.
Design and optimization of on-chip capillary electrophoresis 总被引:1,自引:0,他引:1
We present a systematic, experimentally validated method of designing electrokinetic injections for on-chip capillary electrophoresis applications. This method can be used to predict point-wise and charge-coupled device (CCD)-imaged electropherograms using estimates of species mobilities, diffusivities and initial sample plug parameters. A simple Taylor dispersion model is used to characterize electrophoretic separations in terms of resolution and signal-to-noise ratio (SNR). Detection convolutions using Gaussian and Boxcar detector response functions are used to relate optimal conditions for resolution and signal as a function of relevant system parameters including electroosmotic mobility, sample injection length, detector length scale, and the length-to-detector. Analytical solutions show a tradeoff between signal-to-noise ratio and resolution with respect to dimensionless injection width and length to the detector. In contrast, there is no tradeoff with respect to the Peclet number as increases in Peclet number favor both SNR and separation solution (R). We validate our model with quantitative epifluorescence visualizations of electrophoretic separation experiments in a simple cross channel microchip. For the pure advection regime of dispersion, we use numerical simulations of the transient convective diffusion processes associated with electrokinetics together with an optimization algorithm to design a voltage control scheme which produces an injection plug that has minimal advective dispersion. We also validate this optimal injection scheme using fluorescence visualizations. These validations show that optimized voltage scheme produces injections with a standard deviation less than one-fifth of the width of the microchannel. 相似文献