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Title: PSECMAC Intelligent Insulin Schedule for Diabetic Blood Glucose Management Under Nonmeal Announcement
Creator: Teddy, S. D., Quek, C., Lai, E. M.-k., Cinar, A.
Date: 2010-03
Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Description: Therapeutically, the closed-loop blood glucose-insulin regulation paradigm via a controllable insulin pump offers a potential solution to the...
Show moreTherapeutically, the closed-loop blood glucose-insulin regulation paradigm via a controllable insulin pump offers a potential solution to the management of diabetes. However, the development of such a closed-loop regulatory system to date has been hampered by two main issues: 1) the limited knowledge on the complex human physiological process of glucose-insulin metabolism that prevents a precise modeling of the biological blood glucose control loop; and 2) the vast metabolic biodiversity of the diabetic population due to varying exogneous and endogenous disturbances such as food intake, exercise, stress, and hormonal factors, etc. In addition, current attempts of closed-loop glucose regulatory techniques generally require some form of prior meal announcement and this constitutes a severe limitation to the applicability of such systems. In this paper, we present a novel intelligent insulin schedule based on the pseudo self-evolving cerebellar model articulation controller (PSECMAC) associative learning memory model that emulates the healthy human insulin response to food ingestion. The proposed PSECMAC intelligent insulin schedule requires no prior meal announcement and delivers the necessary insulin dosage based only on the observed blood glucose fluctuations. Using a simulated healthy subject, the proposed PSECMAC insulin schedule is demonstrated to be able to accurately capture the complex human glucose-insulin dynamics and robustly addresses the intraperson metabolic variability. Subsequently, the PSECMAC intelligent insulin schedule is employed on a group of type-1 diabetic patients to regulate their impaired blood glucose levels. Preliminary simulation results are highly encouraging. The work reported in this paper represents a major paradigm shift in the management of diabetes where patient compliance is poor and the need for prior meal announcement under current treatment regimes poses a significant challenge to an active lifestyle.
Endnote format citation for DOI:10.1109/TNN.2009.2036726
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Title: VIBRATIONAL CONTROL OF AN EXOTHERMIC CSTR - PRODUCTIVITY IMPROVEMENT BY MULTIPLE INPUT OSCILLATIONS
Creator: Shu, X. S., Rigopoulos, K., Cinar, A.
Date: 1989-02
Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Description: A. Cinar et al. (1987) have shown that vibrational control of an exothermic continuous stirred tank reactor (CSTR) by vibrating the total flow...
Show moreA. Cinar et al. (1987) have shown that vibrational control of an exothermic continuous stirred tank reactor (CSTR) by vibrating the total flow rate modifies its behavior and leads to stabilized operation in its unstable steady-state region. Here, the effect of multiple vibrating inputs and the contribution of their phase shift are investigated. Theoretical and experimental results indicate productivity improvement and amplitude reduction in reactor temperature swings by vibrating both input flow rate and input concentrations.
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Title: Automated control of high temperature short time pasteurization
Creator: Negiz, A., Cinar, A., Schlesser, J. E., Ramanauskas, P., Armstrong, D. J., Stroup, W.
Date: 1996-12
Publisher: ELSEVIER SCI LTD
Description: Cascade and multivariable control of a high temperature shot? time (HTST) pasteurization system were tested and compared with the performance...
Show moreCascade and multivariable control of a high temperature shot? time (HTST) pasteurization system were tested and compared with the performance of single-loop feedback control. Multivariable control was implemented on the basis of computations of product temperatures that yield equivalent lethality at a residence time of 15 s at 161 degrees F in the holding tube. Both cascade and multivariable controllers reduced product temperature fluctuations and overshoot compared to single-loop feedback control. Multivariable control was based on on-line computation of equivalent total lethality and it permitted operation at variable flow rates or at the most desirable temperatures for product quality and functionality. Copyright (C) 1996 Elsevier Science Ltd.
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Title: FORCED PERIODIC OPERATION OF TUBULAR REACTORS
Creator: Ozgulsen, F., Cinar, A.
Date: 1994-10
Publisher: PERGAMON-ELSEVIER SCIENCE LTD
Description: Forced periodic operation of tubular reactors can increase conversion and yield if proper operating conditions and forcing policies are...
Show moreForced periodic operation of tubular reactors can increase conversion and yield if proper operating conditions and forcing policies are selected. A numerical approach is proposed for computing the effects of periodic input forcing by a shooting algorithm. Such computational tools permit the assessment of the benefits of forced periodic operation of a specific reactor system and the identification of the ranges of operating conditions where forced periodic operation is beneficial. This information provides valuable insight for planning detailed experimental studies. Determining the influential input variables and bracketing the ranges of the operating conditions for improving reactor performance will reduce significantly the experiments needed for selecting the most favorable reactor operation policies. The application of the numerical algorithm is illustrated by assessing the benefits of forced periodic operation to a CO oxidation reactor model. The results reveal substantial improvement in performance with slow cycling in feed concentration.
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Title: Multivariable MPC system performance assessment, monitoring, and diagnosis
Creator: Schaffer, J., Cinar, A.
Date: 2004-03
Publisher: ELSEVIER SCI LTD
Description: This study focuses on performance assessment and monitoring of model predictive control systems. A methodology is proposed to determine a...
Show moreThis study focuses on performance assessment and monitoring of model predictive control systems. A methodology is proposed to determine a benchmark and monitor model predictive control performance on-line. A performance measure based on the ratio of historical and achieved performance is used for monitoring and a ratio of design and achieved performance is used for diagnosis. Performance monitoring and diagnosis of causes for poor performance are integrated. A real-time knowledge-based system is developed to supervise monitoring and diagnosis activities. Case studies with linear and nonlinear models of an evaporator illustrate the methodology and limitations of linearity assumptions.
Endnote format citation for DOI:10.1016/j.jprocont.2003.07.003
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Title: Multivariate statistical methods for monitoring continuous processes: Assessment of discrimination power of disturbance models and diagnosis of multiple disturbances
Creator: Raich, A. C., Cinar, A.
Date: 1995-11
Publisher: ELSEVIER SCIENCE BV
Description: A new methodology was reported [1,2] for integrated use of principal components analysis (PCA) and discriminant analysis in order to determine...
Show moreA new methodology was reported [1,2] for integrated use of principal components analysis (PCA) and discriminant analysis in order to determine out-of-control status of a continuous process and to diagnose the source causes for abnormal behavior. Most of the disturbances were identified with good rates of success, with a higher success rate for step or ramp type of disturbances. Quantitative tools that evaluate overlap and similarity between high-dimensional PCA models are proposed in this communication, and their implications on determining the discrimination power of PCA models of processes operating under disturbances are discussed. Diagnosis of several disturbances occurring simultaneously is also investigated. The criterion developed provide upper limits of discrimination power of various single and multiple process disturbances. The techniques developed are illustrated by assessing the process described by the Tennessee Eastman Control Challenge problem [3].
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Title: INTELLIGENT PROCESS-CONTROL WITH SUPERVISORY KNOWLEDGE-BASED SYSTEMS
Creator: Kendra, S. J., Basila, M. R., Cinar, A.
Date: 1994-06
Description: The integration of a supervisory knowledge-based system (KBS) with a multivariable control system is examined to provide robust multivariable...
Show moreThe integration of a supervisory knowledge-based system (KBS) with a multivariable control system is examined to provide robust multivariable control of a chemical reaction process. The supervisory KBS is capable of monitoring the process to detect system faults as well as assessing control system performance. If a control system performance deficiency is detected, the KBS formulates and implements the necessary corrective controller tuning. This adaptive capability reduces the conservatism of the robust control system. The underlying mechanisms are discussed and the re-tuning ability of the KBS is illustrated by using rigorous simulations of a chemical reaction process
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Title: DESIGN OF RESILIENT CONTROLLABLE CHEMICAL PROCESSES - AN AUTOTHERMAL REACTOR CASE-STUDY
Creator: Chylla, R. W., Cinar, A.
Date: 1990-07
Publisher: AMER CHEMICAL SOC
Description: A technique for the analysis of state-space linear systems is applied to the problem of selection of resilient chemical process designs....
Show moreA technique for the analysis of state-space linear systems is applied to the problem of selection of resilient chemical process designs. Structural Dominance Analysis affords the evaluation of many process design and control configurations and assessment of the effects of potential manipulated variables and disturbances. After a brief presentation of the analysis method, a complex multibed tubular autothermal reactor system is examined. Resilient process configurations, ease of control, and effects of various inputs on reactor state variables and outputs are considered, and effective control configurations are selected.
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Title: Feedback control of a continuous-flow stirred tank reactor with competing autocatalators
Creator: Chaivorapoj, W., Birol, I., Cinar, A., Teymour, F.
Date: 2003-08-06
Publisher: AMER CHEMICAL SOC
Description: Two types of nonlinear feedback control schemes are introduced and analyzed for their capability of recovering the original state of an...
Show moreTwo types of nonlinear feedback control schemes are introduced and analyzed for their capability of recovering the original state of an isothermal continuous-flow stirred tank reactor with one robust cubic autocatalytic species, perturbed by a temporary disturbance of an invading cubic autocatalytic species in the inflow. The control objectives are to eliminate the invading species from the system and to restore the original state of the host species. The extent of applicability of the control design to different nonrobust invading species is studied, when the controller is tuned for a specific invader. Moreover, a time-delay feature is suggested in one of the control schemes developed to achieve the control objectives in systems with poor detection of invading species.
Endnote format citation for DOI:10.1021/ie020427+
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Title: Monitoring of multivariable dynamic processes and sensor auditing
Creator: Negiz, A., Cinar, A.
Date: 1998-10
Publisher: ELSEVIER SCI LTD
Description: Industrial continuous processes are usually operated under closed-loop control, yielding process measurements that are autocorrelated, cross...
Show moreIndustrial continuous processes are usually operated under closed-loop control, yielding process measurements that are autocorrelated, cross correlated, and collinear. A statistical process monitoring (SPM) method based on state variables is introduced to monitor such processes. The statistical model that describes the in-control variability is based on a canonical variate (CV) state space model. The CV state variables are linear combinations of the past process measurements which explain the variability of the future measurements the most, and they are regarded as the principal dynamic dimensions. A T-2 statistic based on the CV state variables is utilized for developing the SPM procedure. The CV state variables are also used for monitoring sensor reliability. An experimental application to a high temperature short time (HTST) pasteurization process illustrates the proposed methodology.
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Title: A modular simulation package for fed-batch fermentation: penicillin production
Creator: Birol, G., Undey, C., Cinar, A.
Date: 2002-11-15
Publisher: PERGAMON-ELSEVIER SCIENCE LTD
Description: Simulation software based on a detailed unstructured model for penicillin production in a fed-batch fermentor has been developed. The model...
Show moreSimulation software based on a detailed unstructured model for penicillin production in a fed-batch fermentor has been developed. The model extends the mechanistic model of Bajpai and Reuss by adding input variables such as pH, temperature, aeration rate, agitation power, and feed flow rate of substrate and introducing the CO2 evolution term. The simulation package was then used for monitoring and fault diagnosis of a typical penicillin fermentation process. The simulator developed may be used for both research and educational purposes and is available at the web site: http://www.chee.iit.edu/ similar to control/software.html.
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Title: A NUMERICAL-METHOD FOR DETERMINING OPTIMAL PARAMETER VALUES IN FORCED PERIODIC OPERATION
Creator: Ozgulsen, F., Adomaitis, R. A., Cinar, A.
Date: 1992-02
Publisher: PERGAMON-ELSEVIER SCIENCE LTD
Description: A numerical approach for determining values of forcing parameters which maximize performance of a periodically forced system is described....
Show moreA numerical approach for determining values of forcing parameters which maximize performance of a periodically forced system is described. Periodic solutions of the system equations plus a differential form of the time-average performance measure are computed with a shooting algorithm. A nonlinear programming package is used to solve the optimization problem. The algorithm is applied to ethylene oxidation process, using the model of a continuous stirred-tank reactor (CSTR).
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Title: A MODEL OBJECT BASED SUPERVISORY EXPERT SYSTEM FOR FAULT TOLERANT CHEMICAL REACTOR CONTROL
Creator: Basila, M. R., Stefanek, G., Cinar, A.
Date: 1990-05
Publisher: PERGAMON-ELSEVIER SCIENCE LTD
Description: An expert system for real-time control of chemical processes provides an environment for coordination of process fault diagnosis, assessment...
Show moreAn expert system for real-time control of chemical processes provides an environment for coordination of process fault diagnosis, assessment of process behavior, automated controller retuning and/or reconfiguration and consequently enables fault-tolerant process control. A supervisory expert system with object-based knowledge representation and heuristic (shallow) and model-based (deep) knowledge is presented. The expert system resides on a PC/386 and communicates with the control system developed in the form of control blocks residing on a PC/286. The prototype of the expert system is developed for retuning model-based controllers to improve the behavior of a packed-bed tubular CO oxidation reactor under autothermal operation. MOBECS is a supervisory expert system designed to tailor the process control system for a tubular autothermal reactor in response to process or control system faults, and changes in the process behavior. Specific functions include process fault diagnosis, control system performance monitoring and trouble-shooting, controller tuning and control system restructuring. As this work progresses, we will also address the problems of sensor placement, state estimation and process identification. Because of the high degree of coupling and interaction between process and control system entities, objects are the best knowledge representation for a process control expert system. The class—object structures of MOBECS is divided into three orthogonal trees representing the process and control system hierarchies and the topology of the system. Using this structure, knowledge is divided into general knowledge applicable to any process or control system and knowledge that is domain specific. The general knowledge is stored in the class structures and, together with generalized rules, forms a knowledge base kernel. This permits rapid prototyping of other applications of MOBECS. Properties are defined as high as possible in the class tree structure and inherited downwards. Knowledge specific to the process is stored in the objects at the leaves of the trees. Rules form the reasoning portion of the knowledge base and contain the causal relationships, meta-knowledge and performance monitoring functions. Rules that perform general monitoring and troubleshooting are applied at the class level through pattern matching. Rule sets are linked through context relationships to identify indirect relationships to the inference engine. These relationships are used with the process topology tree to reduce the search space when a fault is detected. The process monitoring and instability detection rules have been tested by simulating the inputs to the expert system. At the present time, experimental validation of the MOBECS prototype is being undertaken. Once the MOBECS prototype has been fully tested, the knowledge base will be extended to incorporate more complex fault diagnosis, state estimation, sensor placement and controller restructuring.
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Title: VIBRATIONAL CONTROL OF AN EXOTHERMIC REACTION IN A CSTR - THEORY AND EXPERIMENTS
Creator: Cinar, A., Deng, J., Meerkov, S. M., Shu, X. S.
Date: 1987-03
Publisher: AMER INST CHEMICAL ENGINEERS
Description: Vibrational control is a method for modification of dynamic properties of linear and nonlinear systems by introducing fast, zero-average...
Show moreVibrational control is a method for modification of dynamic properties of linear and nonlinear systems by introducing fast, zero-average oscillations in the system's parameters. In this paper, forced oscillations introduced in the input flow rates of an exothermic continuous stirred-tank reactor (CSTR) are shown to result in a modification of the S-shaped steady state curve. This modification leads to a possibility of operating a CSTR at an asymptotically stable period regime located in the vicinity of an unstable steady state of the reactor system with stationary input flow rates. Thus, vibrations of the input flow rates can be viewed as a stabilizing mechanism for exothermic CSTR's.
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Title: Nonlinear time series models for multivariable dynamic processes
Creator: Cinar, A.
Date: 1995-11
Publisher: ELSEVIER SCIENCE BV
Description: Several paradigms are available for developing nonlinear dynamic input-output models of processes. Polynomial models, threshold models, models...
Show moreSeveral paradigms are available for developing nonlinear dynamic input-output models of processes. Polynomial models, threshold models, models based on spline functions, and polynomial models with exponential and trigonometric functions can describe various types of nonlinearities and pathological behavior observed in many physical processes. A unified nonlinear model development framework is not available, and the search of the appropriate nonlinear structure is part of the model development effort. Various artificial neural network structures and nonlinear time series model structures are presented and illustrated by developing a model from data sets generated by a series of example systems. The use of a nonlinear model development paradigm which is not compatible with the types of nonlinearities that exist in the data can have a significant effect on model development effort and model accuracy.
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Title: MATHEMATICAL-MODELS OF COCURRENT SPRAY-DRYING
Creator: Negiz, A., Lagergren, E. S., Cinar, A.
Date: 1995-10
Publisher: AMER CHEMICAL SOC
Description: A steady state mathematical model for a cocurrent spray dryer-is developed. The model includes the mass, momentum, and energy balances for a...
Show moreA steady state mathematical model for a cocurrent spray dryer-is developed. The model includes the mass, momentum, and energy balances for a single drying droplet as well as the total energy and mass balances of the drying medium. A log normal droplet size distribution is assumed to hold at the exit of the twin-fluid atomizer located at the top of the drying chamber. The discretization of this log normal distribution with a certain number of bins yields a system of nonlinear coupled first-order differential equations as a function of the axial distance of the drying chamber. This system of equations is used to compute the axial changes in droplet diameter, density, velocity, moisture, and temperature for the droplets at each representative bin. Furthermore, the distributions of important process parameters such as droplet moisture content, diameter, density, and temperature are also obtainable along the length of the chamber. On the basis of the developed model, a constrained nonlinear optimization problem is solved, where the exit particle moisture content is minimized with respect to the process inputs subjected to a fixed mean particle diameter at the chamber exit. Response surface studies based on empirical models are also performed to illustrate the effectiveness of these techniques in achieving the optimal solution when an a priori model is not available. The structure of empirical models obtained from the model is shown to be in agreement with the structure of the empirical models obtained from the experimental studies.
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Title: NUMERICAL SINGULARITY ANALYSIS
Creator: Adomaitis, R. A., Cinar, A.
Date: 1991
Publisher: PERGAMON-ELSEVIER SCIENCE LTD
Description: A numerical scheme is presented for classifying the different static bifurcation behaviors exhibited by a nonlinear system in its remaining...
Show moreA numerical scheme is presented for classifying the different static bifurcation behaviors exhibited by a nonlinear system in its remaining parameter space. This numerical technique differs from previously published schemes in that the application of singularity theory is done numerically and requires no explicit differentiations of the system in question. It also does not require the reduction of the mathematical model to a scalar equation. The utility of this multivariable scheme will be demonstrated through an application to a seven PDE tubular packed-bed reactor model.
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Title: Online batch/fed-batch process performance monitoring, quality prediction, and variable-contribution analysis for diagnosis
Creator: Undey, C., Ertunc, S., Cinar, A.
Date: 2003-10-01
Publisher: AMER CHEMICAL SOC
Description: An integrated online multivariate statistical process monitoring (MSPM), quality prediction, and fault diagnosis framework is developed for...
Show moreAn integrated online multivariate statistical process monitoring (MSPM), quality prediction, and fault diagnosis framework is developed for batch processes. Batch data from I batches, with J process variables measured at K time points generate a three-way array of size I x K x J. Unfolding this three-way array into a two-way matrix of size IK x J by preserving the variable direction is advantageous for developing online MSPM methods because it does not require estimation of future portions of new batches. Two different multiway partial least squares (MPLS) models are developed. The first model (MPLSV) is developed between the data matrix (IK x J) and the local batch time (or an indicator variable) for online MSPM. The second model (MPLSB) is developed between the rearranged data matrix in the batch direction (I x KJ) and the final quality matrix for online prediction of end-of-batch quality. The problem of discontinuity in process variable measurements due to operation switching (or moving to a different phase) that causes problems in alignment and modeling is addressed. Control limits on variable contribution plots are used to improve fault diagnosis capabilities of the MSPM framework. Case studies from a simulated fed-batch penicillin fermentation illustrate the implementation of the methodology.
Endnote format citation for DOI:10.1021/ie0208218
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Title: Automated control and monitoring of thermal processing using high temperature, short time pasteurization
Creator: Schlesser, J. E., Armstrong, D. J., Cinar, A., Ramanauskas, P., Negiz, A.
Date: 1997-10
Publisher: AMER DAIRY SCIENCE ASSOC
Description: High temperature, short time pasteurization was used to evaluate a computer-based system for controlling the pasteurization process, acquiring...
Show moreHigh temperature, short time pasteurization was used to evaluate a computer-based system for controlling the pasteurization process, acquiring data, and monitoring records. Software was used for the control of hot water temperature, flow rate through the centrifugal timing pump, and diversion of under-processed product. Three types of control strategies were conducted: single loop, cascade, and multivariable. The single loop control strategy showed the most rapid responses to temperature changes, but the temperature response curve was slowest to return to its set point. The cascade control strategy showed slower recoveries to temperature changes, but the temperature response curve was smoother. The multivariable control strategy responded slightly faster than the cascade control strategy, and the temperature response curve was slightly smoother than the cascade control strategy. The multivariable control strategy was able to control the flow diversion valve by the use of a lethality controller. The data acquisition system, used to monitor the data obtained from the high temperature, short-time pasteurization system, was within +/- 0.1 degrees C of the temperature recorded by the safety thermal limit recorder. Reliability was determined by examining the changes in the position of the flow diversion valve to identify process deviations and by comparing the changes to the event marker on circular charts. The data acquisition system was an effective alternative for monitoring the completeness of data.
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Title: Agent-based control of autocatalytic replicators in networks of reactors
Creator: Tatara, E., Birol, I., Teymour, F., Cinar, A.
Date: 2005-03-15
Publisher: PERGAMON-ELSEVIER SCIENCE LTD
Description: Spatially distributed systems such as reactor networks hosting multiple autocatalytic species demonstrate a rich spectrum of complex behavior....
Show moreSpatially distributed systems such as reactor networks hosting multiple autocatalytic species demonstrate a rich spectrum of complex behavior. From a control systems perspective, spatially distributed systems offer a difficult control challenge because of their distributed nature, nonlinearity, and high order. Furthermore, manipulation of the network states may require simultaneous control actions in different parts of the system and may need transients through several operating regimes to achieve the desired operation. The lack of accurate and computationally efficient model-based techniques for large, spatially distributed systems results in complications in controlling the system, either in disturbance rejection or changing the operational regimes of the system. A hierarchical, agent-based control structure is presented whereby local control objectives may be changed in order to achieve the global control objective. The performance of the control system is demonstrated for several global objectives. The challenge posed is to control the spatial distribution of autocatalytic species in a network of five reactors hosting two species using the interaction flow rates as the manipulated variables. The multi-agent control system is able to effectively explore the parameter space of the network and intelligently manipulate the network flow rates such that the desired spatial distribution of species is achieved.
Endnote format citation for DOI:10.1016/j.compchemeng.2004.09.022
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