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Modeling and estimation of measurement errors
234
Book reviews / Flow Measurement and Instrumentation 12 (2001) 233–235
80’s, with revisions. Both are adequate, but the latest designs of linerless magmeters are not addressed. When comparing the two chapters, the section on ultrasonics is far better illustrated and one of the best chapters in the book for overall content. Mass type flowmeters are addressed in Chapters 14 to 17. I liked the way the different principles within this overall grouping have been split into the various chapters. The older technology designs are only briefly addressed in chapter 14, which has relatively few illustrations. Some of the practical realizations (similar to those shown in the ultrasonics chapter) could have illustrated the way the principles evolved (e.g. the Peerburg meter for example). By comparison, the thermal mass flow section is well illustrated and with a good theoretical section. In recent years, there has been a great deal of interest usage and focus on the Coriolis meter. This section of the market grew dramatically in the late 80’s and early 90’s and as a result several of the early companies were purchased by larger organizations. The review of industrial designs therefore in chapter 17 is somewhat historical and outdated. Single straight-through designs are now commonplace in many applications since the technology was perfected a few years ago. The section on insertion and point velocity devices (chapter 18) looks at a useful and cost effective family of instruments. There has been a good deal of work on the theory of these devices and it would have been better to have included the basic theory of point sensing and velocity area integration, to give the readers and prospective users a better appreciation of the in-situ performance of such devices. Chapter 19 on Control Systems seemed out of place in a flow handbook. The recent rapid developments in protocols, the publication of the Field bus standards and computer technology innovation make it difficult to keep such a subject current. Some industries use LONWORKS or ETHERNET systems in conjunction with flowmeters and these are not mentioned. When looking at manufacturing and markets for flowmeters, the manufacturers themselves have comprehensive figures. There are also independent organizations that sell such data (such as F&S, D&B, ARC etc). Trade bodies, Government departments and some professional institutions also publish figures from time to time so there is generally a good deal of market data available. The current world market for all types of flowmeters in all industries is around $2.4B, with the US the dominant single market at almost $1B (around 40%) and the European contribution around $800M. The data therefore given in Chapter 20 is a historical snapshot and is useful to show how rapidly some sectors have developed. The sections at the end of the book on flowmeter standards and a list of conferences complement the extensive reference listing very well. It is clear the Author has
consulted a great many papers, conferences and opinions in the preparation of the book. It is also clear the Author has spent many hours putting together a great deal of practical information, so the title of the book correctly reflects the subject matter. I would have liked to see a chapter devoted just to installation effects. There are good sections throughout the book on the recommended way to install the various designs (and the errors you may expect if you do not), but most recent conferences on flow measurement seem to have at least one or two sessions just looking at installation effects. There have been a large number of good papers published in recent years and the practical side of the book would benefit from all these being discussed in a common section. I have already said the various aspects of uncertainty should be grouped together into a new chapter. These two subjects (correct installation and uncertainty appreciation) are the cornerstones to successful flowmeter usage. Linking these subjects towards the end would tie the whole treatise together very nicely. I would also liked to have seen some references to the large amount CFD work going on that is aimed at improving our understanding of the effects of fittings on flowmeter performance. Finally, the summary of the work: Will I use it—yes: Can I recommend it—again yes. I hope the constructive comments made in the above review will be incorporated into a second version. It is a good basic flow handbook and when used with some of the other standard texts (ISA, Miller etc.) will give a good all-round view of a complex subject. Richard Furness Endress & Hauser, Indianapolis, Indiana, USA PII: S 0 9 5 5 - 5 9 8 6 ( 0 0 ) 0 0 0 4 9 - 2
Modeling and estimation of measurement errors Michelle Neuilly and CETAMA; Intercept, Andover, Price £109.50, ISBN 898298-59-9 Michele Neuilly’s and CETAMA’s book is a nearly 700 pages advanced guide in the use of statistical methods for the treatment of measurement data. It is surely not a book for those unfamiliar with the subject and thus it is not suggested for those being at an introductory level to it. For those being more familiar with measurements’ errors theory, a very good knowledge in statistics and some patience is rather demanded in order to follow up the unfolding of the only 5 highly fragmented chapters of the book and its 7 Appendices. The latter readers could really gain from the highly specialised richness of the text.
Book reviews / Flow Measurement and Instrumentation 12 (2001) 233–235
As the authors refer in the introduction, this book was produced as a revision of an earlier book of the Commission for the establishment of methods of Analysis (CETAMA). The writers tried to adapt the former book to specific calls and interdisciplinary needs for the analysis of measurement data and errors in general — really a task of enormous difficulty. It is suspected that it is this effort which led to a presentation style that generally lacks the necessary coherence as well as the meant general coverage of the book title. Particularly, the necessary links and cuts between disparate topics are not clearly indicated, thus failing in that respect to bring out the essence of estimation of measurement errors in a rather general way as the book’s title suggests. The communication efficiency with the reader is rather pure and becomes worse with the absence (!) of a glossary of symbols and notation, so necessary for such a rich mathematical text. The book is mainly focused on the statistical modeling and estimation of measurement errors. It has a practical orientation and could be of considerable use to people applying these techniques in chemical analysis. Undoubtedly, the material on measurements’ statistical data processing is rich and it can also be useful to scientists and engineers from various other disciplines as well. The fundamental statistical theory of measurements is covered in Chapter I and in the Appendices and as it was said, the presentation style is more advanced than that of normal introductory texts to statistical theory. Chapter I includes definitions of random, systematic and overall errors for direct measurements as well as the basic theoretical statistical concepts which could characterise sets of observations (histograms, population parameters, main probability distributions families etc.) Chapter II deals with model estimation and testing, which is mainly attributed to the selection of suitable probability distributions for the analysis of collections of data, as well as the estimation of the parameters of the distributions. The authors’ procedure of searching suitable models to data starts by employing general parametric estimation methods, while non-parametric testing methods are also employed and mixed in the same chapter, though without this clear cut between the two methods as it is generally the case in classical books regarding estimation methods. This makes the following of the chapter quite difficult. My personal interest and awareness is raised by reading chapters III and IV where factorial experiments and designs, as well as ANOVA (ANalysis Of VAriance) techniques are presented along with particular applications to interlaboratory experiments and comparisons. This subject performs particular interest, especially today where global trading and international transactions
235
are steadily increase. Issues such as reference quantities obtained and certified from such interlaboratory experiments, were, and still are forming the basis of the global trading. In that respect, the material presented in chapter III alone could form an extremely useful guide for those involved directly or indirectly with metrology, laboratories, quality and other relevant areas and additionally seems to include critical issues that are published well in time by the authors. Thus, Section III.2.3 regarding interlaboratory studies for the specification of standards with the objective of determining the certified value of a reference quantity, as well as the following issues of chapter III, are really matters not easily founded in the relevant literature, forming the heart of the book. Similarly, chapter IV includes most of the material necessary for the calculation of the uncertainty in the final result of a measurement and the study of the propagation of different sources of error to the final result. The simple, though critical issue of how random errors of a measurement can be completely masked due to a large scale (limited resolution) of the measuring instrument, is very illustratively presented in sections IV.5.1– 3 and useful treatment rules of the subject are given. The remaining sections of this chapter are also very interesting and particularly the summary presentation of the characteristics of a measurement method (repeatability, accuracy, reproducibility) with the section IV.4 on the sensitivity of a measurement method attracting most interest. An interest that is kept vivid also in the last chapter V, in which linear and non-linear regressions and advanced calculations of calibration curves, and a lot of worthwhile material which is applicable to a big diversity of scientific and engineering fields are presented. In conclusion, Michele Neuilly’s and CETAMA attempt can be characterised as a success, that loses considerable extra value by the lack of examples from scientific areas other than that of the chemical analysis. Generally, it is a useful text for those familiar with the subject relatively pure in the use of visual aids (pictures, graphs) but rich in its mathematical context, containing a lot of illustrative examples and test cases from the area of chemical analysis. The book casts plenty of light in the rather difficult and wide subject of estimation of measurement errors, which has definitely been enriched by this considerable effort of the professionals involved in its writing. Christos Papadopoulos 5 N. Fitsiori Street Serres, Greece 20 May 2000 PII: S 0 9 5 5 - 5 9 8 6 ( 0 1 ) 0 0 0 1 7 - 6
Book reviews / Flow Measurement and Instrumentation 12 (2001) 233–235
80’s, with revisions. Both are adequate, but the latest designs of linerless magmeters are not addressed. When comparing the two chapters, the section on ultrasonics is far better illustrated and one of the best chapters in the book for overall content. Mass type flowmeters are addressed in Chapters 14 to 17. I liked the way the different principles within this overall grouping have been split into the various chapters. The older technology designs are only briefly addressed in chapter 14, which has relatively few illustrations. Some of the practical realizations (similar to those shown in the ultrasonics chapter) could have illustrated the way the principles evolved (e.g. the Peerburg meter for example). By comparison, the thermal mass flow section is well illustrated and with a good theoretical section. In recent years, there has been a great deal of interest usage and focus on the Coriolis meter. This section of the market grew dramatically in the late 80’s and early 90’s and as a result several of the early companies were purchased by larger organizations. The review of industrial designs therefore in chapter 17 is somewhat historical and outdated. Single straight-through designs are now commonplace in many applications since the technology was perfected a few years ago. The section on insertion and point velocity devices (chapter 18) looks at a useful and cost effective family of instruments. There has been a good deal of work on the theory of these devices and it would have been better to have included the basic theory of point sensing and velocity area integration, to give the readers and prospective users a better appreciation of the in-situ performance of such devices. Chapter 19 on Control Systems seemed out of place in a flow handbook. The recent rapid developments in protocols, the publication of the Field bus standards and computer technology innovation make it difficult to keep such a subject current. Some industries use LONWORKS or ETHERNET systems in conjunction with flowmeters and these are not mentioned. When looking at manufacturing and markets for flowmeters, the manufacturers themselves have comprehensive figures. There are also independent organizations that sell such data (such as F&S, D&B, ARC etc). Trade bodies, Government departments and some professional institutions also publish figures from time to time so there is generally a good deal of market data available. The current world market for all types of flowmeters in all industries is around $2.4B, with the US the dominant single market at almost $1B (around 40%) and the European contribution around $800M. The data therefore given in Chapter 20 is a historical snapshot and is useful to show how rapidly some sectors have developed. The sections at the end of the book on flowmeter standards and a list of conferences complement the extensive reference listing very well. It is clear the Author has
consulted a great many papers, conferences and opinions in the preparation of the book. It is also clear the Author has spent many hours putting together a great deal of practical information, so the title of the book correctly reflects the subject matter. I would have liked to see a chapter devoted just to installation effects. There are good sections throughout the book on the recommended way to install the various designs (and the errors you may expect if you do not), but most recent conferences on flow measurement seem to have at least one or two sessions just looking at installation effects. There have been a large number of good papers published in recent years and the practical side of the book would benefit from all these being discussed in a common section. I have already said the various aspects of uncertainty should be grouped together into a new chapter. These two subjects (correct installation and uncertainty appreciation) are the cornerstones to successful flowmeter usage. Linking these subjects towards the end would tie the whole treatise together very nicely. I would also liked to have seen some references to the large amount CFD work going on that is aimed at improving our understanding of the effects of fittings on flowmeter performance. Finally, the summary of the work: Will I use it—yes: Can I recommend it—again yes. I hope the constructive comments made in the above review will be incorporated into a second version. It is a good basic flow handbook and when used with some of the other standard texts (ISA, Miller etc.) will give a good all-round view of a complex subject. Richard Furness Endress & Hauser, Indianapolis, Indiana, USA PII: S 0 9 5 5 - 5 9 8 6 ( 0 0 ) 0 0 0 4 9 - 2
Modeling and estimation of measurement errors Michelle Neuilly and CETAMA; Intercept, Andover, Price £109.50, ISBN 898298-59-9 Michele Neuilly’s and CETAMA’s book is a nearly 700 pages advanced guide in the use of statistical methods for the treatment of measurement data. It is surely not a book for those unfamiliar with the subject and thus it is not suggested for those being at an introductory level to it. For those being more familiar with measurements’ errors theory, a very good knowledge in statistics and some patience is rather demanded in order to follow up the unfolding of the only 5 highly fragmented chapters of the book and its 7 Appendices. The latter readers could really gain from the highly specialised richness of the text.
Book reviews / Flow Measurement and Instrumentation 12 (2001) 233–235
As the authors refer in the introduction, this book was produced as a revision of an earlier book of the Commission for the establishment of methods of Analysis (CETAMA). The writers tried to adapt the former book to specific calls and interdisciplinary needs for the analysis of measurement data and errors in general — really a task of enormous difficulty. It is suspected that it is this effort which led to a presentation style that generally lacks the necessary coherence as well as the meant general coverage of the book title. Particularly, the necessary links and cuts between disparate topics are not clearly indicated, thus failing in that respect to bring out the essence of estimation of measurement errors in a rather general way as the book’s title suggests. The communication efficiency with the reader is rather pure and becomes worse with the absence (!) of a glossary of symbols and notation, so necessary for such a rich mathematical text. The book is mainly focused on the statistical modeling and estimation of measurement errors. It has a practical orientation and could be of considerable use to people applying these techniques in chemical analysis. Undoubtedly, the material on measurements’ statistical data processing is rich and it can also be useful to scientists and engineers from various other disciplines as well. The fundamental statistical theory of measurements is covered in Chapter I and in the Appendices and as it was said, the presentation style is more advanced than that of normal introductory texts to statistical theory. Chapter I includes definitions of random, systematic and overall errors for direct measurements as well as the basic theoretical statistical concepts which could characterise sets of observations (histograms, population parameters, main probability distributions families etc.) Chapter II deals with model estimation and testing, which is mainly attributed to the selection of suitable probability distributions for the analysis of collections of data, as well as the estimation of the parameters of the distributions. The authors’ procedure of searching suitable models to data starts by employing general parametric estimation methods, while non-parametric testing methods are also employed and mixed in the same chapter, though without this clear cut between the two methods as it is generally the case in classical books regarding estimation methods. This makes the following of the chapter quite difficult. My personal interest and awareness is raised by reading chapters III and IV where factorial experiments and designs, as well as ANOVA (ANalysis Of VAriance) techniques are presented along with particular applications to interlaboratory experiments and comparisons. This subject performs particular interest, especially today where global trading and international transactions
235
are steadily increase. Issues such as reference quantities obtained and certified from such interlaboratory experiments, were, and still are forming the basis of the global trading. In that respect, the material presented in chapter III alone could form an extremely useful guide for those involved directly or indirectly with metrology, laboratories, quality and other relevant areas and additionally seems to include critical issues that are published well in time by the authors. Thus, Section III.2.3 regarding interlaboratory studies for the specification of standards with the objective of determining the certified value of a reference quantity, as well as the following issues of chapter III, are really matters not easily founded in the relevant literature, forming the heart of the book. Similarly, chapter IV includes most of the material necessary for the calculation of the uncertainty in the final result of a measurement and the study of the propagation of different sources of error to the final result. The simple, though critical issue of how random errors of a measurement can be completely masked due to a large scale (limited resolution) of the measuring instrument, is very illustratively presented in sections IV.5.1– 3 and useful treatment rules of the subject are given. The remaining sections of this chapter are also very interesting and particularly the summary presentation of the characteristics of a measurement method (repeatability, accuracy, reproducibility) with the section IV.4 on the sensitivity of a measurement method attracting most interest. An interest that is kept vivid also in the last chapter V, in which linear and non-linear regressions and advanced calculations of calibration curves, and a lot of worthwhile material which is applicable to a big diversity of scientific and engineering fields are presented. In conclusion, Michele Neuilly’s and CETAMA attempt can be characterised as a success, that loses considerable extra value by the lack of examples from scientific areas other than that of the chemical analysis. Generally, it is a useful text for those familiar with the subject relatively pure in the use of visual aids (pictures, graphs) but rich in its mathematical context, containing a lot of illustrative examples and test cases from the area of chemical analysis. The book casts plenty of light in the rather difficult and wide subject of estimation of measurement errors, which has definitely been enriched by this considerable effort of the professionals involved in its writing. Christos Papadopoulos 5 N. Fitsiori Street Serres, Greece 20 May 2000 PII: S 0 9 5 5 - 5 9 8 6 ( 0 1 ) 0 0 0 1 7 - 6