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Title: Modeling, monitoring and control strategies for high temperature short time pasteurization systems - 3. Statistical monitoring of product lethality and process sensor reliability
Creator: Negiz, A., Ramanauskas, P., Cinar, A., Schlesser, J. E., Armstrong, D. J.
Date: 1998-02
Publisher: ELSEVIER SCI LTD
Description: Statistical process monitoring (SPM) is used in food processing industries to improve productivity and product quality. SPM can also provide...
Show moreStatistical process monitoring (SPM) is used in food processing industries to improve productivity and product quality. SPM can also provide information to operators on how close a process is to non-compliance to product safety limits, and carry out periodic checks of sensor accuracy at high frequency. Traditional SPM tools such as Shewhart charts are not appropriate for continuous food processes because of autocorrelation in data. Four alternative SPM techniques are presented and applied to high temperature short time (HTST) dairy pasteurization. The study attempted to achieve compliance of the HTST process operation with the recommended Pasteurized Milk Ordinance by providing a margin between the alarm limits of the monitoring chart and the safety limits. Monitoring of residuals and parameter change detection techniques ave used for monitoring processes with autocorrelated variables. Hotelling's T-2 and residuals of canonical variates techniques are used for monitoring multivariable processes.
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Title: INSTABILITY MODES EXCITED BY NATURAL SCREECH TONES IN A SUPERSONIC RECTANGULAR JET
Creator: Raman, G, Rice, Ej
Date: 1994-12
Publisher: AMER INST PHYSICS

Title: VIBRATIONAL CONTROL OF CHEMICAL REACTORS - STABILIZATION AND CONVERSION IMPROVEMENT IN AN EXOTHERMIC CSTR
Creator: Cinar, A., Rigopoulos, K., Shu, X., Meerkov, S. M.
Date: 1987
Publisher: GORDON BREACH SCI PUBL LTD
Description: Vibrational control is an open-loop control strategy implemented by fast zero-average oscillations in the input variables of a system. It has...
Show moreVibrational control is an open-loop control strategy implemented by fast zero-average oscillations in the input variables of a system. It has been previously shown that vibrational control of an exothermic reaction in a CSTR, introduced via oscillations in the input flow rate, modifies the dynamic behavior of the reactor and enables its stabilized operation in the unstable steady-state region. In the present paper it is shown that simultaneous vibrations in input flow rate and concentration lead, in addition to a reduction of the amplitude of oscillations in reactor temperature and/or increase in reactant conversion. It is also shown that the phase shift between the vibrations of the two input variables affects the behavior of the system as well as the amplitude, the frequency and the form of forcing functions.
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Title: Statistical monitoring of multistage, multiphase batch processes
Creator: Undey, C., Cinar, A.
Date: 2002-10
Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Description: The monitoring of intermediate phases of production is as important as monitoring and control of the final stage. Here a framework is proposed...
Show moreThe monitoring of intermediate phases of production is as important as monitoring and control of the final stage. Here a framework is proposed for monitoring overall process performance at the end of each batch.
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Title: An intelligent system for multivariate statistical process monitoring and diagnosis
Creator: Tatara, E., Cinar, A.
Date: 2002-04
Publisher: I S A-THE INSTRUMENTATION SYSTEMS AUTOMATION SOC
Description: A knowledge-based system (KBS) was designed for automated system identification, process monitoring, and diagnosis of sensor faults. The real...
Show moreA knowledge-based system (KBS) was designed for automated system identification, process monitoring, and diagnosis of sensor faults. The real-time KBS consists of a supervisory system using G2 KBS development software linked with external statistical modules for system identification and sensor fault diagnosis. The various statistical techniques were prototyped in MATLAB, converted to ANSI C code, and linked with the G2 Standard Interface. The KBS automatically performs all operations of data collection, identification, monitoring, and sensor fault diagnosis with little or no input from the user. Navigation throughout the KBS is via menu buttons on each user-accessible screen. Selected process variables are displayed on charts showing the history of the variables over a period of time. Multivariate statistical tests and contribution plots are also shown graphically. The KBS was evaluated using simulation studies with a polymerization reactor through a nonlinear dynamic model. Both normal operation conditions as well as conditions of process disturbances were observed to evaluate the KBS performance. Specific user-defined disturbances were added to the simulation, and the KBS correctly diagnosed both process and sensor faults when present.
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Title: Real-time batch process supervision by integrated knowledge-based systems and multivariate statistical methods
Creator: Undey, C., Tatara, E., Cinar, A.
Date: 2003-08
Publisher: PERGAMON-ELSEVIER SCIENCE LTD
Description: Real-time supervision of batch operations during the progress of a batch run offers many advantages over end-of-batch quality control. Process...
Show moreReal-time supervision of batch operations during the progress of a batch run offers many advantages over end-of-batch quality control. Process monitoring, quality estimation, and fault diagnosis activities are automated and supervised by embedding them into a real-time knowledge-based system (RTKBS). Interpretation of multivariate charts is also automated through a generic rule-base for efficient alarm handling and fault diagnosis. Multivariate statistical techniques such as multiway partial least squares (MPLS) provide a powerful modeling, monitoring, and supervision framework. Online process monitoring techniques are developed and extended to include predictions of end-of-batch quality measurements during the progress of a batch run. The integrated RTKBS and the implementation of MPLS-based process monitoring and quality control are illustrated using a fed-batch penicillin production benchmark process simulator.
Endnote format citation for DOI:10.1016/j.engappai.2003.09.003
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Title: Gerry-meandering: An Assessment of the Congressional District Model of Depository Allocation (preprint): AhrensGriffinedrev1
Creator: Ahrens, Aric G., Griffin, Luke A.
Date: 2003-06
Description: The preprint of a published article dealing with the effect of allocating Federal Depositories by Congressional district. Conclusions drawn...
Show moreThe preprint of a published article dealing with the effect of allocating Federal Depositories by Congressional district. Conclusions drawn include the fact that due to redistricting that occurs after each decennial census, over time some districts may have within their boundaries a greater number than the two depositories that Congressional district allocation was intended to produce. Likewise, over time shifting boundaries of districts have created districts that have no depositories whatsoever.
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Title: Advances in Understanding Supersonic Jet Screech: Review and Perspective
Creator: Raman, G.
Date: 1998-02
Publisher: Pergamon - Elsevier Science Ltd
Description: Screech tones are produced by imperfectly expanded jets under certain conditions. This paper provides an overview of developments in the field...
Show moreScreech tones are produced by imperfectly expanded jets under certain conditions. This paper provides an overview of developments in the field of supersonic jet screech. The overview includes a historical background, summary of recent developments, and a critical assessment of our current understanding of screech. The subject material has been categorized as described in the table of contents given below. (C) 1998 Elsevier Science Ltd.
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Title: DYNAMIC BEHAVIOR OF PERIODIC FEEDBACK-CONTROL SYSTEMS
Creator: Kendra, S., Cinar, A.
Date: 1991
Publisher: GORDON BREACH SCI PUBL LTD
Description: Periodic feedback is a control strategy implemented by fast zero-average oscillations in the parameters of the control law. It is well known...
Show morePeriodic feedback is a control strategy implemented by fast zero-average oscillations in the parameters of the control law. It is well known that time invariant feedback control offers no means for zeros relocation. Periodic feedback allows zeros relocation in an asymptotic sense, resulting in improved closed loop characteristics, such as increased gain margins.
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Title: Coupling of Twin Supersonic Jets of Complex Geometry
Creator: Raman, G.
Date: 1999-10
Publisher: American Inst Aeronaut Astronaut
Description: Fundamental issues about the coupling of twin supersonic jets of complex geometry are examined. It is shown that screech tones from twin...
Show moreFundamental issues about the coupling of twin supersonic jets of complex geometry are examined. It is shown that screech tones from twin rectangular nozzles with double-beveled exit geometries can couple. Unlike coupling of twin rectangular jets of uniform geometry, the coupling here is more intricate because simultaneous multiple frequencies with a different spanwise modal structure are present. The coupling produces two frequencies, one of which is lower than the screech frequency of either jet. Although many coupling modes are kinematically permissible, the twin jets prefer two specific modes, and in some cases these two coupling modes coexist at different frequencies. Despite the geometric complexity we can effectively predict frequencies of tones from both single and twin coupled jets using the waveguide approach. It is hoped that these results and insights will assist those simulating screech for the purpose of tailoring shock-containing complex twin jets that minimize sonic fatigue failure of aircraft structures.
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Title: Batch process monitoring and its application to polymerization systems
Creator: Undey, C., Ertunc, S., Tatara, E., Teymour, F., Cinar, A.
Date: 2004-01
Publisher: WILEY-V C H VERLAG GMBH
Description: Slight changes in raw material properties or operating conditions during critical periods of operation of batch and semi-batch polymerization...
Show moreSlight changes in raw material properties or operating conditions during critical periods of operation of batch and semi-batch polymerization reactors may have a strong influence on reaction mechanism and impact final product quality. Online process monitoring, fault detection, fault diagnosis, and product quality prediction in real-time ensure safe reactor operation and warn operators about excursions from normal operation that may lead to deterioration in product properties. Multivariate statistical process monitoring and quality prediction using multiway principal components analysis and multiway partial least squares have been successful in detecting abnormalities in process operation and product quality. When abnormal process operation is detected, fault diagnosis tools are used to determine the source cause of the deviation. Illustrative case studies are presented via simulated polyvinyl acetate polymerization.
Endnote format citation for DOI:10.1002/masy.200450210
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Title: Effect of Asymmetric Manipulations in Autocatalytic Networks
Creator: Balasubramanian, Sukanya, Cinar, Ali, Teymour, Fouad
Date: 2010-06-02
Publisher: AMER CHEMICAL SOC
Description: In this paper, we show that heterogeneous networks can be configured and reconfigured to operate in flexible spatial patterns The concept is...
Show moreIn this paper, we show that heterogeneous networks can be configured and reconfigured to operate in flexible spatial patterns The concept is demonstrated by using a square grid of continuous stirred tank reactors with nearest neighbor interactions and hosting multiple cubic autocatalytic species Asymmetry is introduced in the system by allowing for different feed flow rates in the reactors. A heterogeneous system offers expanded phase space, improved stability. and coexistence characteristics The advantages of asymmetry are studied using bifurcation diagrams, continuation studies. and dynamics
Endnote format citation for DOI:10.1021/ie901096v
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Title: PLS, balanced, and canonical variate realization techniques for identifying VARMA models in state space
Creator: Negiz, A., Cinar, A.
Date: 1997-10
Publisher: ELSEVIER SCIENCE BV
Description: This paper demonstrates the application of PLS regression, balanced realization, and canonical variate (CV) state space modeling techniques in...
Show moreThis paper demonstrates the application of PLS regression, balanced realization, and canonical variate (CV) state space modeling techniques in identifying stationary vector autoregressive moving average (VARMA) type of time series models in state space. An example VARMA process model is used to generate data, carry out modeling activities, and compare the three model development techniques. All realization methods provide equivalent state space models. Balanced realization can not handle singularities in the covariance matrix of past observations while all other methods can accommodate such singularities. Balanced realization and classical PLS do not provide minimal state variables that are orthogonal. 'Orthogonal states' PLS and canonical variate state space realization give orthogonal state variables that provide robust parameter estimates from real data, however the PLS method requires an additional singular value decomposition step.
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Title: MODE SPECTRA OF NATURAL DISTURBANCES IN A CIRCULAR JET AND THE EFFECT OF ACOUSTIC FORCING
Creator: Raman, G, Rice, Ej, Reshotko, E
Date: 1994-10
Publisher: SPRINGER VERLAG
Description: A modal spectrum technique was used to study coherent instability modes (both axisymmetric and azimuthal) triggered by naturally occurring...
Show moreA modal spectrum technique was used to study coherent instability modes (both axisymmetric and azimuthal) triggered by naturally occurring disturbances in a circular jet. This technique was applied to a high Reynolds number (400,000) jet for both untripped (transitional) and tripped (turbulent) nozzle exit boundary layers, with both cases having a core turbulence level of 0.15%. The region up to the end of the potential core was dominated by the axisymmetric mode, with the azimuthal modes dominating further downstream. The growth of the azimuthal modes was observed closer to the nozzle exit for the jet with a transitional boundary layer. Whether for locally parallel flow or slowly diverging flow, even at low levels of acoustic forcing, the inviscid linear theory is seen to be inadequate for predicting the amplitude of the forced mode. In contrast, the energy integral approach reasonably predicts the evolution of the forced mode.
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Title: EVALUATION OF FLIP-FLOP JET NOZZLES FOR USE AS PRACTICAL EXCITATION DEVICES
Creator: Raman, G, Rice, Ej, Cornelius, Dm
Date: 1994-09
Publisher: ASME-AMER SOC MECHANICAL ENG
Description: This paper describes the flowfield characteristics of the flip-flop jet nozzle and the potential for using this nozzle as a practical...
Show moreThis paper describes the flowfield characteristics of the flip-flop jet nozzle and the potential for using this nozzle as a practical excitation device. It appears from the existing body of published information that there is a lack of data on the parameters affecting the operation of such nozzles and on the mechanism of operation of these nozzles. An attempt is made in the present work to study the important parameters affecting the operation and performance of a flip-flop jet nozzle. Measurements were carried out to systematically assess the effect of varying the nozzle pressure ratio (NPR) as well as the length and volume of the feedback tube on the frequency of oscillation of this device. Flow visualization was used to obtain a better understanding of the jet flowfield and of the processes occurring within the feedback tube. The frequency of oscillation of the flip-flop jet depended significantly on the feedback tube length and volume as well as on the nozzle pressure ratio. In contrast, the coherent velocity perturbation levels did not depend on the above-mentioned parameters. The data presented in this paper would be useful for modeling such flip-flop excitation devices that are potentially useful for controlling practical shear flows.
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Title: DEVELOPMENT OF PHASED TWIN FLIP-FLOP JETS
Creator: Raman, G, Rice, Ej
Date: 1994-07
Publisher: ASME-AMER SOC MECHANICAL ENG
Description: The flip-flop nozzle is a device that can produce an oscillating jet flow without any moving parts. There is now a renewed interest in such...
Show moreThe flip-flop nozzle is a device that can produce an oscillating jet flow without any moving parts. There is now a renewed interest in such nozzles due to their potential for use as excitation devices in practical applications. An experiment aimed at developing twin flip-flop jets that operate at prescribed frequencies and phase differences was performed. The phasing was achieved using two different nozzle interconnection schemes. In one configuration the two jets flapped in-phase and in another they flapped out-of-phase with respect to each other. In either configuration the frequencies of oscillation of both jets were equal. When one of the jets was run at a constant high velocity and the velocity of the second jet was increased gradually, the higher velocity jet determined the frequency of oscillation of both jets. The two flip-flop jet configurations described in this paper could be used to excite a primary jet flow in either an anti-symmetric (sinuous) or a symmetric (varicose) mode.
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Title: An adaptive robust M-estimator for nonparametric nonlinear system identification
Creator: Wu, X. C., Cinar, A.
Date: 1996-08
Publisher: BUTTERWORTH-HEINEMANN LTD
Description: An adaptive robust M-estimator for nonparametric nonlinear system identification is proposed. This M-estimator is optimal over a broad class...
Show moreAn adaptive robust M-estimator for nonparametric nonlinear system identification is proposed. This M-estimator is optimal over a broad class of distributions in the sense of maximum likelihood estimation. The error distributions are described by the generalized exponential distribution family. It combines nonparametric regression techniques to form a powerful procedure for nonlinear system identification. The adaptive procedure's excellent performance characteristics are illustrated in a Monte Carlo study by comparing the results with previous methods.
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Title: Interpreting ECG data by integrating statistical and artificial intelligence tools
Creator: Tatara, E., Cinar, A.
Date: 2002-01
Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Description: The use of an automated system integrating data conditioning, statistical methods, and artificial intelligence tools to summarize and...
Show moreThe use of an automated system integrating data conditioning, statistical methods, and artificial intelligence tools to summarize and interpret high-frequency physiological data such as the electrocardiogram is investigated. The development of a methodology and its associated tools for real-time patient monitoring and diagnosis is accomplished by using the commercial programming environments MATLAB and G2, a real-time knowledge-based system (KBS) development shell. Data interpretation and classification is performed by integrating statistical classification methods and knowledge-based techniques with a graphical user interface that provides quick access to the analysis results as well as the original data. A KBS was developed that incorporates various statistical methods with a rule-based decision system to detect abnormal situations, provide preliminary interpretation and diagnosis, and to report these findings to the healthcare provider
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Title: Revolutionary Persuasion, Thomas Paine's Influential Rhetoric in Common Sense
Creator: Purdy, Michael
Date: 2011-12, 2011-12
Publisher: IIT Humanities Department, Undergraduate Writing Contest
Description: At a pivotal time in early American history, one man was able to influence the hearts and minds of an entire burgeoning nation by way of pen...
Show moreAt a pivotal time in early American history, one man was able to influence the hearts and minds of an entire burgeoning nation by way of pen and parchment. His name was Thomas Paine, and his revolutionary pamphlet was titled "Common Sense." This paper provides an in-depth analysis of Thomas Paine's Common Sense pamphlet in regards to persuasive communication and rhetoric and how it ultimately swayed the American colonists toward separation from the tyrannical motherland.
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Title: Easy Access, Early Exit? The Internet and the FDLP (preprint): GriffinAhrens2004edrev2markup
Creator: Griffin, Luke A., Ahrens, Aric G.
Date: 2004-07
Description: The article presents information on Federal Depository Library Program (FDLP). The majority of the twentieth century saw a marked growth in...
Show moreThe article presents information on Federal Depository Library Program (FDLP). The majority of the twentieth century saw a marked growth in the number of libraries participating in FDLP. The FDLP was established by Congressional resolution on December 27, 1813. On December 1, 1814, the American Antiquarian Society of Worcester, Massachusetts received the first documents distributed to a non-governmental body and became the first depository library. The primary purpose of the program was preservation of the historical record, not dissemination. Staff and funding issues and the availability of resources via the Internet points to the weight that libraries may be placing on the ability to provide information via the Internet on their decisions to remain in or to leave the FDLP. In today's work environment, in which increased productivity is expected and doing more with less is essential, the Internet can be an obvious alternative to physical collections, which require space and greater staff time and resources. In the last decade, the essential association between the ability to provide access to government information and participation in the FDLP has broken down.
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