The Experts below are selected from a list of 120 Experts worldwide ranked by ideXlab platform
Dara Cummins - One of the best experts on this subject based on the ideXlab platform.
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a review of sensor calibration monitoring for calibration Interval Extension in nuclear power plants
2012Co-Authors: Jamie B Coble, Hash Hashemian, Brent Shumaker, Pradeep Ramuhalli, Ryan M Meyer, Leonard J Bond, Dara CumminsAbstract:Currently in the United States, periodic sensor recalibration is required for all safety-related sensors, typically occurring at every refueling outage, and it has emerged as a critical path item for shortening outage duration in some plants. Online monitoring can be employed to identify those sensors that require calibration, allowing for calibration of only those sensors that need it. International application of calibration monitoring, such as at the Sizewell B plant in United Kingdom, has shown that sensors may operate for eight years, or longer, within calibration tolerances. This issue is expected to also be important as the United States looks to the next generation of reactor designs (such as small modular reactors and advanced concepts), given the anticipated longer refueling cycles, proposed advanced sensors, and digital instrumentation and control systems. The U.S. Nuclear Regulatory Commission (NRC) accepted the general concept of online monitoring for sensor calibration monitoring in 2000, but no U.S. plants have been granted the necessary license amendment to apply it. This report presents a state-of-the-art assessment of online calibration monitoring in the nuclear power industry, including sensors, calibration practice, and online monitoring algorithms. This assessment identifies key research needs and gaps that prohibit integration of the NRC-approved more » online calibration monitoring system in the U.S. nuclear industry. Several needs are identified, including the quantification of uncertainty in online calibration assessment; accurate determination of calibration acceptance criteria and quantification of the effect of acceptance criteria variability on system performance; and assessment of the feasibility of using virtual sensor estimates to replace identified faulty sensors in order to extend operation to the next convenient maintenance opportunity. Understanding the degradation of sensors and the impact of this degradation on signals is key to developing technical basis to support acceptance criteria and set point decisions, particularly for advanced sensors which do not yet have a cumulative history of operating performance. « less
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Calibration monitoring for sensor calibration Interval Extension: Identifying technical gaps
FIIW 2012 - 2012 Future of Instrumentation International Workshop Proceedings, 2012Co-Authors: Jamie Coble, Hash Hashemian, Brent Shumaker, Ryan Meyer, Pradeep Ramuhalli, Dara CumminsAbstract:Currently in the United States, periodic sensor recalibration is required for all safety-related sensors, typically occurring at every refueling outage; and it has emerged as a critical path item for shortening outage duration in some plants. International application of calibration monitoring has shown that sensors may operate for longer periods within calibration tolerances. This issue is expected to also be important as the United States looks to the next generation of reactor designs (such as small modular reactors and advanced reactor concepts), given the anticipated longer refueling cycles, proposed advanced sensors, and digital instrumentation and control systems. Online monitoring (OLM) can be employed to identify those sensors that require calibration, allowing for calibration of only those sensors that need it. The U.S. Nuclear Regulatory Commission (NRC) accepted the general concept of OLM for sensor calibration monitoring in 2000, but no U.S. plants have been granted the necessary license amendment to apply it. This paper summarizes a recent state-of-the-art assessment of online calibration monitoring in the nuclear power industry, including sensors, calibration practice, and OLM algorithms. This assessment identifies key research needs and gaps that prohibit integration of the NRC-approved online calibration monitoring system in the U.S. nuclear power industry. Several technical needs were identified, including an understanding of the impacts of sensor degradation on measurements for both conventional and emerging sensors; the quantification of uncertainty in online calibration assessment; determination of calibration acceptance criteria and quantification of the effect of acceptance criteria variability on system performance; and assessment of the feasibility of using virtual sensor estimates to replace identified faulty sensors in order to extend operation to the next convenient maintenance opportunity.
Hash Hashemian - One of the best experts on this subject based on the ideXlab platform.
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a review of sensor calibration monitoring for calibration Interval Extension in nuclear power plants
2012Co-Authors: Jamie B Coble, Hash Hashemian, Brent Shumaker, Pradeep Ramuhalli, Ryan M Meyer, Leonard J Bond, Dara CumminsAbstract:Currently in the United States, periodic sensor recalibration is required for all safety-related sensors, typically occurring at every refueling outage, and it has emerged as a critical path item for shortening outage duration in some plants. Online monitoring can be employed to identify those sensors that require calibration, allowing for calibration of only those sensors that need it. International application of calibration monitoring, such as at the Sizewell B plant in United Kingdom, has shown that sensors may operate for eight years, or longer, within calibration tolerances. This issue is expected to also be important as the United States looks to the next generation of reactor designs (such as small modular reactors and advanced concepts), given the anticipated longer refueling cycles, proposed advanced sensors, and digital instrumentation and control systems. The U.S. Nuclear Regulatory Commission (NRC) accepted the general concept of online monitoring for sensor calibration monitoring in 2000, but no U.S. plants have been granted the necessary license amendment to apply it. This report presents a state-of-the-art assessment of online calibration monitoring in the nuclear power industry, including sensors, calibration practice, and online monitoring algorithms. This assessment identifies key research needs and gaps that prohibit integration of the NRC-approved more » online calibration monitoring system in the U.S. nuclear industry. Several needs are identified, including the quantification of uncertainty in online calibration assessment; accurate determination of calibration acceptance criteria and quantification of the effect of acceptance criteria variability on system performance; and assessment of the feasibility of using virtual sensor estimates to replace identified faulty sensors in order to extend operation to the next convenient maintenance opportunity. Understanding the degradation of sensors and the impact of this degradation on signals is key to developing technical basis to support acceptance criteria and set point decisions, particularly for advanced sensors which do not yet have a cumulative history of operating performance. « less
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Calibration monitoring for sensor calibration Interval Extension: Identifying technical gaps
FIIW 2012 - 2012 Future of Instrumentation International Workshop Proceedings, 2012Co-Authors: Jamie Coble, Hash Hashemian, Brent Shumaker, Ryan Meyer, Pradeep Ramuhalli, Dara CumminsAbstract:Currently in the United States, periodic sensor recalibration is required for all safety-related sensors, typically occurring at every refueling outage; and it has emerged as a critical path item for shortening outage duration in some plants. International application of calibration monitoring has shown that sensors may operate for longer periods within calibration tolerances. This issue is expected to also be important as the United States looks to the next generation of reactor designs (such as small modular reactors and advanced reactor concepts), given the anticipated longer refueling cycles, proposed advanced sensors, and digital instrumentation and control systems. Online monitoring (OLM) can be employed to identify those sensors that require calibration, allowing for calibration of only those sensors that need it. The U.S. Nuclear Regulatory Commission (NRC) accepted the general concept of OLM for sensor calibration monitoring in 2000, but no U.S. plants have been granted the necessary license amendment to apply it. This paper summarizes a recent state-of-the-art assessment of online calibration monitoring in the nuclear power industry, including sensors, calibration practice, and OLM algorithms. This assessment identifies key research needs and gaps that prohibit integration of the NRC-approved online calibration monitoring system in the U.S. nuclear power industry. Several technical needs were identified, including an understanding of the impacts of sensor degradation on measurements for both conventional and emerging sensors; the quantification of uncertainty in online calibration assessment; determination of calibration acceptance criteria and quantification of the effect of acceptance criteria variability on system performance; and assessment of the feasibility of using virtual sensor estimates to replace identified faulty sensors in order to extend operation to the next convenient maintenance opportunity.
Brent Shumaker - One of the best experts on this subject based on the ideXlab platform.
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a review of sensor calibration monitoring for calibration Interval Extension in nuclear power plants
2012Co-Authors: Jamie B Coble, Hash Hashemian, Brent Shumaker, Pradeep Ramuhalli, Ryan M Meyer, Leonard J Bond, Dara CumminsAbstract:Currently in the United States, periodic sensor recalibration is required for all safety-related sensors, typically occurring at every refueling outage, and it has emerged as a critical path item for shortening outage duration in some plants. Online monitoring can be employed to identify those sensors that require calibration, allowing for calibration of only those sensors that need it. International application of calibration monitoring, such as at the Sizewell B plant in United Kingdom, has shown that sensors may operate for eight years, or longer, within calibration tolerances. This issue is expected to also be important as the United States looks to the next generation of reactor designs (such as small modular reactors and advanced concepts), given the anticipated longer refueling cycles, proposed advanced sensors, and digital instrumentation and control systems. The U.S. Nuclear Regulatory Commission (NRC) accepted the general concept of online monitoring for sensor calibration monitoring in 2000, but no U.S. plants have been granted the necessary license amendment to apply it. This report presents a state-of-the-art assessment of online calibration monitoring in the nuclear power industry, including sensors, calibration practice, and online monitoring algorithms. This assessment identifies key research needs and gaps that prohibit integration of the NRC-approved more » online calibration monitoring system in the U.S. nuclear industry. Several needs are identified, including the quantification of uncertainty in online calibration assessment; accurate determination of calibration acceptance criteria and quantification of the effect of acceptance criteria variability on system performance; and assessment of the feasibility of using virtual sensor estimates to replace identified faulty sensors in order to extend operation to the next convenient maintenance opportunity. Understanding the degradation of sensors and the impact of this degradation on signals is key to developing technical basis to support acceptance criteria and set point decisions, particularly for advanced sensors which do not yet have a cumulative history of operating performance. « less
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Calibration monitoring for sensor calibration Interval Extension: Identifying technical gaps
FIIW 2012 - 2012 Future of Instrumentation International Workshop Proceedings, 2012Co-Authors: Jamie Coble, Hash Hashemian, Brent Shumaker, Ryan Meyer, Pradeep Ramuhalli, Dara CumminsAbstract:Currently in the United States, periodic sensor recalibration is required for all safety-related sensors, typically occurring at every refueling outage; and it has emerged as a critical path item for shortening outage duration in some plants. International application of calibration monitoring has shown that sensors may operate for longer periods within calibration tolerances. This issue is expected to also be important as the United States looks to the next generation of reactor designs (such as small modular reactors and advanced reactor concepts), given the anticipated longer refueling cycles, proposed advanced sensors, and digital instrumentation and control systems. Online monitoring (OLM) can be employed to identify those sensors that require calibration, allowing for calibration of only those sensors that need it. The U.S. Nuclear Regulatory Commission (NRC) accepted the general concept of OLM for sensor calibration monitoring in 2000, but no U.S. plants have been granted the necessary license amendment to apply it. This paper summarizes a recent state-of-the-art assessment of online calibration monitoring in the nuclear power industry, including sensors, calibration practice, and OLM algorithms. This assessment identifies key research needs and gaps that prohibit integration of the NRC-approved online calibration monitoring system in the U.S. nuclear power industry. Several technical needs were identified, including an understanding of the impacts of sensor degradation on measurements for both conventional and emerging sensors; the quantification of uncertainty in online calibration assessment; determination of calibration acceptance criteria and quantification of the effect of acceptance criteria variability on system performance; and assessment of the feasibility of using virtual sensor estimates to replace identified faulty sensors in order to extend operation to the next convenient maintenance opportunity.
Pradeep Ramuhalli - One of the best experts on this subject based on the ideXlab platform.
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a review of sensor calibration monitoring for calibration Interval Extension in nuclear power plants
2012Co-Authors: Jamie B Coble, Hash Hashemian, Brent Shumaker, Pradeep Ramuhalli, Ryan M Meyer, Leonard J Bond, Dara CumminsAbstract:Currently in the United States, periodic sensor recalibration is required for all safety-related sensors, typically occurring at every refueling outage, and it has emerged as a critical path item for shortening outage duration in some plants. Online monitoring can be employed to identify those sensors that require calibration, allowing for calibration of only those sensors that need it. International application of calibration monitoring, such as at the Sizewell B plant in United Kingdom, has shown that sensors may operate for eight years, or longer, within calibration tolerances. This issue is expected to also be important as the United States looks to the next generation of reactor designs (such as small modular reactors and advanced concepts), given the anticipated longer refueling cycles, proposed advanced sensors, and digital instrumentation and control systems. The U.S. Nuclear Regulatory Commission (NRC) accepted the general concept of online monitoring for sensor calibration monitoring in 2000, but no U.S. plants have been granted the necessary license amendment to apply it. This report presents a state-of-the-art assessment of online calibration monitoring in the nuclear power industry, including sensors, calibration practice, and online monitoring algorithms. This assessment identifies key research needs and gaps that prohibit integration of the NRC-approved more » online calibration monitoring system in the U.S. nuclear industry. Several needs are identified, including the quantification of uncertainty in online calibration assessment; accurate determination of calibration acceptance criteria and quantification of the effect of acceptance criteria variability on system performance; and assessment of the feasibility of using virtual sensor estimates to replace identified faulty sensors in order to extend operation to the next convenient maintenance opportunity. Understanding the degradation of sensors and the impact of this degradation on signals is key to developing technical basis to support acceptance criteria and set point decisions, particularly for advanced sensors which do not yet have a cumulative history of operating performance. « less
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Calibration monitoring for sensor calibration Interval Extension: Identifying technical gaps
FIIW 2012 - 2012 Future of Instrumentation International Workshop Proceedings, 2012Co-Authors: Jamie Coble, Hash Hashemian, Brent Shumaker, Ryan Meyer, Pradeep Ramuhalli, Dara CumminsAbstract:Currently in the United States, periodic sensor recalibration is required for all safety-related sensors, typically occurring at every refueling outage; and it has emerged as a critical path item for shortening outage duration in some plants. International application of calibration monitoring has shown that sensors may operate for longer periods within calibration tolerances. This issue is expected to also be important as the United States looks to the next generation of reactor designs (such as small modular reactors and advanced reactor concepts), given the anticipated longer refueling cycles, proposed advanced sensors, and digital instrumentation and control systems. Online monitoring (OLM) can be employed to identify those sensors that require calibration, allowing for calibration of only those sensors that need it. The U.S. Nuclear Regulatory Commission (NRC) accepted the general concept of OLM for sensor calibration monitoring in 2000, but no U.S. plants have been granted the necessary license amendment to apply it. This paper summarizes a recent state-of-the-art assessment of online calibration monitoring in the nuclear power industry, including sensors, calibration practice, and OLM algorithms. This assessment identifies key research needs and gaps that prohibit integration of the NRC-approved online calibration monitoring system in the U.S. nuclear power industry. Several technical needs were identified, including an understanding of the impacts of sensor degradation on measurements for both conventional and emerging sensors; the quantification of uncertainty in online calibration assessment; determination of calibration acceptance criteria and quantification of the effect of acceptance criteria variability on system performance; and assessment of the feasibility of using virtual sensor estimates to replace identified faulty sensors in order to extend operation to the next convenient maintenance opportunity.
Ludmila Dymova - One of the best experts on this subject based on the ideXlab platform.
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a direct Interval Extension of topsis method
Expert Systems With Applications, 2013Co-Authors: Ludmila Dymova, Pavel Sevastjanov, Anna TikhonenkoAbstract:The TOPSIS method is a technique for order preference by similarity to ideal solution. This technique currently is one of the most popular methods for Multiple Criteria Decision Making (MCDM). The TOPSIS method was primary developed for dealing with only real-valued data. In many cases, it is hard to present precisely the exact ratings of alternatives with respect to local criteria and as a result these ratings are considered as Intervals. There are some papers devoted to the Interval Extensions of TOPSIS method, but these Extensions are based on different heuristic approaches to definition of positive and negative ideal solutions. These ideal solutions are presented by real values or Intervals, which are not attainable in a decision matrix. Since this is in contradiction with basics of classical TOPSIS method, in this paper we propose a new direct approach to Interval Extension of TOPSIS method which is free of heuristic assumptions and limitations of known methods. Using numerical examples we show that ''direct Interval Extension of TOPSIS method'' may provide the final ranking of alternatives which is substantially different from the results obtained using known methods.
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a method for solving systems of linear Interval equations applied to the leontief input output model of economics
Expert Systems With Applications, 2013Co-Authors: Ludmila Dymova, Pavel Sevastjanov, M PilarekAbstract:A new approach to solving systems of linear Interval equations based on the generalized procedure of Interval Extension is proposed. This procedure is based on the treatment of Interval zero as an Interval centered around zero, and for this reason it is called the ''Interval extended zero'' method. Since the ''Interval extended zero'' method provides a fuzzy solution to Interval equations, its Interval representations are proposed. It is shown that they may be naturally treated as modified operations of Interval division. These operations are used for the modified Interval Extensions of known numerical methods for solving systems of linear equations and finally for solving systems of linear Interval equations. Using a well known example, it is shown that the solution obtained by the proposed method can be treated as an inner Interval approximation of the united solution and an outer Interval approximation of the tolerable solution, and lies within the range of possible AE-solutions between the extreme tolerable and united solutions. Generally, we can say that the proposed method provides the results which can be treated as approximate formal solutions sometimes referred to as algebraic solutions. Seven known examples are used to illustrate the method's efficacy and advantages in comparison with known methods providing formal (algebraic) solutions to systems of linear Interval equations. It is shown that a new method provides results which are close to the so-called maximal inner solutions (the corresponding method was developed by Kupriyanova, Zyuzin and Markov) and the algebraic solutions obtained by the subdifferential Newton method proposed by Shary. It is important that the proposed method makes it possible to avoid inverted Interval solutions. The influence of the system's size and number of zero entries on the results is analyzed by applying the proposed method to the Leontief input-output model of economics.
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a new method for solving Interval and fuzzy equations linear case
Information Sciences, 2009Co-Authors: Pavel Sevastjanov, Ludmila DymovaAbstract:A new approach to the solution of Interval and fuzzy equations based on the generalized procedure of Interval Extension called ''Interval extended zero'' method is proposed. The central for the proposed approach is the treatment of the Interval zero as an Interval centered around zero. It is shown that such proposition is not of heuristic nature, but is the direct consequence of the Interval subtraction operation. Some methodological problems concerned with this definition of Interval zero are discussed. It is shown that the resulting solution of Interval linear equations based on the proposed method may be naturally treated as a fuzzy number. An important advantage of a new method is that it substantially decreases the excess width effect. On the other hand, we show that it can be used as a reliable practical tool for solving linear Interval and fuzzy equations as well as the systems of them. The features of the method are illustrated by the example of the solution of the well known Leontief input-output problem in the Interval setting.
