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(101 - 120 of 139)
Pages
- 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.
Endnote format citation
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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.
Endnote format citation
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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
Endnote format citation
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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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- Title
- Easy Access, Early Exit? The Internet and the FDLP (preprint): GriffinAhrens2004edrev1markup
- 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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- Title
- Easy Access, Early Exit? The Internet and the FDLP (preprint): GriffinAhrens2004edrev4markup
- 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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- Title
- Easy Access, Early Exit? The Internet and the FDLP (preprint): GriffinAhrens2004edrev3markup
- 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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- Title
- Easy Access, Early Exit? The Internet and the FDLP (preprint): GriffinAhrens2004edrev2clean
- 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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- Title
- Easy Access, Early Exit? The Internet and the FDLP (preprint): GriffinAhrens2004finalpreprint
- 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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- Title
- Easy Access, Early Exit? The Internet and the FDLP (preprint): GriffinAhrens2004edrev1clean
- 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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- Title
- Easy Access, Early Exit? The Internet and the FDLP (preprint): GriffinAhrens2004ver1rev1
- 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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- Title
- Easy Access, Early Exit? The Internet and the FDLP (preprint): GriffinAhrens2004ver1
- 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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- Title
- Influence of Injector Location on Part-Load Performance Characteristics of Natural Gas Direct-Injection in a Spark Ignition Engine
- Creator
- Hall, Carrie, Sevik, James, Pamminger, Michael, Wallner, Thomas, Scarcelli, Riccardo, Boyer, Brad, Wooldridge, Steven, Miers, Scott
- Date
- 2016
- Publisher
- SAE International
- Title
- Using Peer Navigators to Address the Integrated Healthcare Needs of African Americans with Serious Mental Illness
- Creator
- Corrigan, Patrick
- Date
- 2017, 2017
- Publisher
- American Psychiatric Association
- Description
-
Objective...
Show moreObjective Impact of a peer navigator program (PNP) develop by a community based participatory research team was examined on African Americans with serious mental illness who were homeless. Methods Research participants were randomized to PNP or a treatment-as-usual control group for one year. Data on physical and mental health, recovery, and quality of life were collected at baseline, 4, 8 and 12 months. Results Findings from group by trial ANOVAs of omnibus measures of the four constructs showed significant impact over the one year for participants in PNP compared to control described by small to moderate effect sizes. These differences emerged even though both groups showed significant improvements in reduced homelessness and insurance coverage. Conclusions Implications for improving in-the-field health care for this population are discussed. Whether these results occurred because navigators were peers per se needs to be examined in future research.
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