ali karimi - Academia.edu (original) (raw)

Papers by ali karimi

Research paper thumbnail of Engineering implications of closed-loop control during cardiac surgery

Engineering implications of closed-loop control during cardiac surgery

Journal of Clinical Monitoring and Computing, 1990

Closed loop control in cardiac surgery is a very difficult problem because of changes in patient ... more Closed loop control in cardiac surgery is a very difficult problem because of changes in patient response, substantial nonrandom external disturbances, random disturbances, and relatively long pure delays between infusion by the pump and initiation of bodily response. System identification models based on real data are crucial for quantitatively describing the relationships encountered in practice. A minimax approach is useful for mathematically describing the control design process as an attempt to choose a single controller capable of coping with a set of patients. It also yields computer-aided design tools. Typical real controllers in complex environments like cardiac surgery contain relatively large numbers of parameters that must be specified. A computer algorithm capable of performing minimax analysis on such problems is available [4]. Design of controllers for complex environments such as cardiac surgery requires the use of computeraided design tools for proper performance. The complexity of the problem and the number of possible combinations of control parameters and architecture may make less exhaustive manual simulation approaches unproductive. Computer-aided design tools are extremely important because they permit much more exhaustive testing prior to application on animals and humans. They permit evaluation of literally millions of combinations of patients and controllers at computer speeds. Manual design searches cannot be done for these large problems.

Research paper thumbnail of Silica sulfuric acid a novel and heterogeneous catalyst for the synthesis of some new oxindole derivatives

Silica sulfuric acid a novel and heterogeneous catalyst for the synthesis of some new oxindole derivatives

Catalysis Communications, 2006

Silica sulfuric acid catalyzed efficiently the electrophilic substitution reaction of an indoles ... more Silica sulfuric acid catalyzed efficiently the electrophilic substitution reaction of an indoles with various isatins in dicholoro methane to afford the corresponding oxindoles derivatives in high yields under rt The catalyst exhibited remarkable reusable activity.

Research paper thumbnail of A Stereoselective Three-Component Reaction: KAl(SO 4 ) 2 ·12H 2 O, an Efficient and Reusable Catalyst for the One-Pot Synthesis of cis- Isoquinolonic Acids

A Stereoselective Three-Component Reaction: KAl(SO 4 ) 2 ·12H 2 O, an Efficient and Reusable Catalyst for the One-Pot Synthesis of cis- Isoquinolonic Acids

Journal of Organic Chemistry, 2005

KAl(SO(4))(2).12H(2)O is found to catalyze efficiently the stereoselective one-pot three-componen... more KAl(SO(4))(2).12H(2)O is found to catalyze efficiently the stereoselective one-pot three-component cyclocondensation of homophthalic anhydride, aldehydes, and amines under mild conditions to afford the corresponding cis-isoquinolonic acids in good yields.

Research paper thumbnail of A Stereoselective Three-Component Reaction: KAl(SO4)2×12H2O, an Efficient and Reusable Catalyst for the One-Pot Synthesis of cis-Isoquinolonic Acids

A Stereoselective Three-Component Reaction: KAl(SO4)2×12H2O, an Efficient and Reusable Catalyst for the One-Pot Synthesis of cis-Isoquinolonic Acids

Cheminform, 2005

KAl(SO(4))(2).12H(2)O is found to catalyze efficiently the stereoselective one-pot three-componen... more KAl(SO(4))(2).12H(2)O is found to catalyze efficiently the stereoselective one-pot three-component cyclocondensation of homophthalic anhydride, aldehydes, and amines under mild conditions to afford the corresponding cis-isoquinolonic acids in good yields.

Research paper thumbnail of A novel one-pot, four component synthesis of some densely functionalized pyrroles

Molecular Diversity, 2003

A new one-pot four component procedure for synthesis of densely functionalized pyrroles using com... more A new one-pot four component procedure for synthesis of densely functionalized pyrroles using commercially available ninhydrin with phosphorane intermediates produced in the reaction between triphenylphosphine, ammonium thiocyanate (or ammonium acetate) and various dialkyl acetylenedicarboxylates was developed.

Research paper thumbnail of Power system stability enhancement using backstepping controller tuned by particle swarm optimization technique

Power system stability enhancement using backstepping controller tuned by particle swarm optimization technique

Abstract A method for designing controls through the excitation system and particle swarm optimiz... more Abstract A method for designing controls through the excitation system and particle swarm optimization technique to search for the optimal setting of the controller gains to improve transient stability and damping is presented. Simulation of multi-machine power systems ...

Research paper thumbnail of Decentralized adaptive backstepping control of electric power systems

Electric Power Systems Research, 2008

In this paper, a decentralized adaptive backstepping excitation controller, tuned using a Particl... more In this paper, a decentralized adaptive backstepping excitation controller, tuned using a Particle Swarm Optimization technique (PSO), is designed for stability enhancement of multi-machine power systems. To achieve decentralization, each machine is modeled as an independent uncertain dynamic subsystem, where the uncertainty is a disturbance that represents the effects of the rest of the system on that particular machine. This disturbance is expressed as a polynomial function of electric power deviation, and its parameters are adapted using PSO. The proposed technique is illustrated with a two-area benchmark power system. This system exhibits inter-area oscillations which are effectively damped with the proposed decentralized controllers under severe contingencies, for which traditional power system stabilizers fail.

Research paper thumbnail of Vapor-phase Diffusion of Benzene in Soil1

Vapor-phase Diffusion of Benzene in Soil1

Journal of Environmental Quality, 1987

Research paper thumbnail of Engineering implications of closed-loop control during cardiac surgery

Engineering implications of closed-loop control during cardiac surgery

Journal of Clinical Monitoring and Computing, 1990

Closed loop control in cardiac surgery is a very difficult problem because of changes in patient ... more Closed loop control in cardiac surgery is a very difficult problem because of changes in patient response, substantial nonrandom external disturbances, random disturbances, and relatively long pure delays between infusion by the pump and initiation of bodily response. System identification models based on real data are crucial for quantitatively describing the relationships encountered in practice. A minimax approach is useful for mathematically describing the control design process as an attempt to choose a single controller capable of coping with a set of patients. It also yields computer-aided design tools. Typical real controllers in complex environments like cardiac surgery contain relatively large numbers of parameters that must be specified. A computer algorithm capable of performing minimax analysis on such problems is available [4]. Design of controllers for complex environments such as cardiac surgery requires the use of computeraided design tools for proper performance. The complexity of the problem and the number of possible combinations of control parameters and architecture may make less exhaustive manual simulation approaches unproductive. Computer-aided design tools are extremely important because they permit much more exhaustive testing prior to application on animals and humans. They permit evaluation of literally millions of combinations of patients and controllers at computer speeds. Manual design searches cannot be done for these large problems.

Research paper thumbnail of Silica sulfuric acid a novel and heterogeneous catalyst for the synthesis of some new oxindole derivatives

Silica sulfuric acid a novel and heterogeneous catalyst for the synthesis of some new oxindole derivatives

Catalysis Communications, 2006

Silica sulfuric acid catalyzed efficiently the electrophilic substitution reaction of an indoles ... more Silica sulfuric acid catalyzed efficiently the electrophilic substitution reaction of an indoles with various isatins in dicholoro methane to afford the corresponding oxindoles derivatives in high yields under rt The catalyst exhibited remarkable reusable activity.

Research paper thumbnail of A Stereoselective Three-Component Reaction: KAl(SO 4 ) 2 ·12H 2 O, an Efficient and Reusable Catalyst for the One-Pot Synthesis of cis- Isoquinolonic Acids

A Stereoselective Three-Component Reaction: KAl(SO 4 ) 2 ·12H 2 O, an Efficient and Reusable Catalyst for the One-Pot Synthesis of cis- Isoquinolonic Acids

Journal of Organic Chemistry, 2005

KAl(SO(4))(2).12H(2)O is found to catalyze efficiently the stereoselective one-pot three-componen... more KAl(SO(4))(2).12H(2)O is found to catalyze efficiently the stereoselective one-pot three-component cyclocondensation of homophthalic anhydride, aldehydes, and amines under mild conditions to afford the corresponding cis-isoquinolonic acids in good yields.

Research paper thumbnail of A Stereoselective Three-Component Reaction: KAl(SO4)2×12H2O, an Efficient and Reusable Catalyst for the One-Pot Synthesis of cis-Isoquinolonic Acids

A Stereoselective Three-Component Reaction: KAl(SO4)2×12H2O, an Efficient and Reusable Catalyst for the One-Pot Synthesis of cis-Isoquinolonic Acids

Cheminform, 2005

KAl(SO(4))(2).12H(2)O is found to catalyze efficiently the stereoselective one-pot three-componen... more KAl(SO(4))(2).12H(2)O is found to catalyze efficiently the stereoselective one-pot three-component cyclocondensation of homophthalic anhydride, aldehydes, and amines under mild conditions to afford the corresponding cis-isoquinolonic acids in good yields.

Research paper thumbnail of A novel one-pot, four component synthesis of some densely functionalized pyrroles

Molecular Diversity, 2003

A new one-pot four component procedure for synthesis of densely functionalized pyrroles using com... more A new one-pot four component procedure for synthesis of densely functionalized pyrroles using commercially available ninhydrin with phosphorane intermediates produced in the reaction between triphenylphosphine, ammonium thiocyanate (or ammonium acetate) and various dialkyl acetylenedicarboxylates was developed.

Research paper thumbnail of Power system stability enhancement using backstepping controller tuned by particle swarm optimization technique

Power system stability enhancement using backstepping controller tuned by particle swarm optimization technique

Abstract A method for designing controls through the excitation system and particle swarm optimiz... more Abstract A method for designing controls through the excitation system and particle swarm optimization technique to search for the optimal setting of the controller gains to improve transient stability and damping is presented. Simulation of multi-machine power systems ...

Research paper thumbnail of Decentralized adaptive backstepping control of electric power systems

Electric Power Systems Research, 2008

In this paper, a decentralized adaptive backstepping excitation controller, tuned using a Particl... more In this paper, a decentralized adaptive backstepping excitation controller, tuned using a Particle Swarm Optimization technique (PSO), is designed for stability enhancement of multi-machine power systems. To achieve decentralization, each machine is modeled as an independent uncertain dynamic subsystem, where the uncertainty is a disturbance that represents the effects of the rest of the system on that particular machine. This disturbance is expressed as a polynomial function of electric power deviation, and its parameters are adapted using PSO. The proposed technique is illustrated with a two-area benchmark power system. This system exhibits inter-area oscillations which are effectively damped with the proposed decentralized controllers under severe contingencies, for which traditional power system stabilizers fail.

Research paper thumbnail of Vapor-phase Diffusion of Benzene in Soil1

Vapor-phase Diffusion of Benzene in Soil1

Journal of Environmental Quality, 1987