Dept. of Production Engineering & Management (DIGEP)

In many branches of industry, most of manufacturing efforts are directed toward producing objects of specific forms and dimensions. Dimensional measurement is an important part of the production cycle, to check products compliance with specifications. For this, many substantial improvements in the existing technologies have been made, and new measuring systems have been introduced. This paper briefly introduces a recent measuring system—mobile spatial coordinate measuring system (MScMS)—which is suitable for performing dimensional measurements of large-size objects (dimension on the order of tens of meters). MScMS, thanks to its distributed wireless sensor network nature, is portable and can be easily arranged around the measured object. Furthermore, it does not require complex setup operations before being ready to perform measurements. After describing how the system works, we will compare it with well-tested and widespread instruments such as traditional coordinate measuring machines (CMMs), showing analogies and differences. The comparison is structured on the basis of different criteria, which are analyzed in detail in the first part of the paper. Although being able to perform similar measurements, CMMs and MScMS are different in technological features. CMMs are able to achieve higher level of accuracy, while MScMS is more flexible, cheap, and can be important to simplify the current measuring practices within large-scale industrial metrology. It can be concluded that these systems can easily coexist, as each system is suitable for specific applications.

This paper focuses the attention on the ch-index, a recent bibliometric indicator similar to the Hirsch (h) index, to evaluate the published research output of a scientist (Ajiferuke and Wolfram, Proceedings of the 12th international conference of the international society for scientometrics and informetrics. Rio de Janeiro, pp. 798–808, 2009). Ch-index is defined as the number such that, for a general group of scientific publications, ch publications are cited by at least ch different citers while the other publications are cited by no more than ch different citers. The basic difference from the classical h is that, according to ch, the diffusion of one author’s publication is evaluated on the basis of the number of different citing authors (or citers), rather than the number of received citations. The goal of this work is to discuss the pros and cons of ch and identify its connection with h. A large sample of scientists in the Quality Engineering/Management field are analyzed so as to investigate the novel indicator’s characteristics. Then, the analysis is preliminarily extended to other scientific disciplines. The most important result is that ch is almost insensitive to self-citations and/or citations made by recurrent citers, and it can be profitably used for complementing h.

This paper analyses some of the most popular scientific journals in the Quality field from the point of view of three bibliometric indicators: the Hirsch (h) index for journals, the total number of citations and the h-spectrum. In particular, h-spectrum is a novel tool based on h, making it possible to (i) identify a reference profile of the typical authors of a journal; (ii) compare different journals; and (iii) provide a rough indication of their ‘bibliometric positioning’ in the scientific community. Results of this analysis can be helpful for guiding potential authors and members of the scientific community in the Quality Engineering/Management area. A large amount of empirical data are presented and discussed. Copyright © 2009 John Wiley & Sons, Ltd.

In a recent work by Anderson, Hankin, and Killworth (2008), Ferrers diagrams and Durfee squares are used to represent the scientific output of a scientist and construct a new h-based bibliometric indicator, the tapered h-index (hT). In the first part of this paper we examine hT, identifying its main drawbacks and weaknesses: an arbitrary scoring system and an illusory increase in discrimination power compared to h. Subsequently, we propose a new bibliometric tool, the citation triad (CT), that better exploits the information contained in a Ferrers diagram, giving a synthetic overview of a scientist's publication output. The advantages of this new approach are discussed in detail. Argument is supported by several examples based on empirical data.

Evaluating the scientific output of researchers, research institutions, academic departments and even universities is a challenging issue. To do this, bibliometric indicators are helpful tools, more and more familiar to research and governmental institutions.This paper proposes a structured method to compare academic research groups within the same discipline, by means of some Hirsch (h) based bibliometric indicators. Precisely, five different typologies of indicators are used so as to depict groups’ bibliometric positioning within the scientific community. A specific analysis concerning the Italian researchers in the scientific sector of Production Technology and Manufacturing Systems is developed. The analysis is supported by empirical data and can be extended to research groups associated to other scientific sectors.

This article analyzes some of the most popular scientific journals in the Manufacturing field from the point of view of four bibliometric indicators: the ISI impact factor (ISI-IF), the Hirsch (h) index-for-journal, the total number of citations and the h-spectrum. h-spectrum is a novel tool based on h, making it possible to (i) identify a reference profile of the typical authors of a journal, (ii) compare different journals and (iii) provide a rough indication of their “bibliometric positioning” in the scientific community. Results of this analysis can be helpful for guiding potential authors and members of the scientific community in the Manufacturing area. Of particular interest is the construction of maps based on h-spectrum and ISI-IF to compare journals and monitor their bibliometric positioning over time. A large amount of empirical data are presented and discussed.

Mobile Spatial coordinate Measuring System (MScMS) is a wireless-sensor-network based system developed at the industrial metrology and quality engineering laboratory of DISPEA – Politecnico di Torino. It has been designed to perform simple and rapid indoor dimensional measurements of large-size volumes (large-scale metrology).It is made up of three basic parts: a “constellation” of wireless devices (Crickets), a mobile probe, and a PC to store and elaborate data. Crickets and mobile probe utilize ultrasound (US) transceivers in order to evaluate mutual distances.The system makes it possible to calculate the position – in terms of spatial coordinates – of the object points “touched” by the probe. Acquired data are then available for different types of elaboration (determination of distances, curves or surfaces of measured objects).In order to protect the system against causes of error such as, for example, US signal diffraction and reflection, external uncontrolled US sources (key jingling, neon blinking, etc.), or software non-acceptable solutions, MScMS implements some statistical tests for on-line diagnostics. Three of them are deeply analyzed in this paper: “energy model-based diagnostics”, “distance model-based diagnostics”, and “sensor physical diagnostics”. For each measurement, if all these tests are satisfied at once, the measured result may be considered acceptable with a specific confidence coefficient. Otherwise, the measurement is rejected.After a general description of the MScMS, the paper focuses on the description of these three on-line diagnostic tools. Some preliminary results achieved by the system prototype are also presented and discussed.

This article analyzes the Quality & Quantity journal from the point of view of some bibliometric indicators: the Hirsch (h) and the g-index for journals, the total number of citations, the h- and the g-spectrum. Journal time evolution is also studied and discussed in detail. As a final point, an interesting issue about how to objectively evaluate the journal popularity in the professional world—rather than the scientific/academic—is presented and left open.

There is currently an increasing trend for accurate measurements of large-scale lengths; in particular, 3D coordinate metrology at length scales of 5 m to 60 m has become a routine requirement in industries such as aircraft and ship construction. This chapter focuses on the Mobile Spatial coordinate Measuring System (MScMS), a new system developed at the Industrial Metrology and Quality Engineering Laboratory of DISPEA of the Politecnico di Torino. Based on a distributed sensor network structure, MScMS is designed to perform simple and rapid indoor dimensional measurements of large-size objects. Using radiofrequency (RF) and ultrasound (US) signals, the system makes it possible to localize-in terms of spatial coordinates-the points “touched” by a wireless mobile probe. To protect the system from potential causes of error, such as US signal diffraction and reflection, external uncontrolled US sources (key jingling, neon blinking, etc.) or unacceptable software solutions, MScMS implements some statistical tests in order to perform online diagnostics. One of these tests is analyzed in depth in this chapter: the “energy model-based diagnostics test.” Although it is specifically developed for the MScMS

Although composition of bibliometric indicators appears to be desirable, in many cases it may be misleading. After a brief introduction on the properties of scales of measurement, the attention of this communication is focused on a recent composite indicator, the hg-index, suggested by Alonso et al. (Scientometrics 82(2):391–400, 2010). Specifically, hg-index has three major criticalities: (1) the hg scale is the result of a composition of the h- and g-indices, which are defined both on ordinal scales, (2) the equivalence classes of hg are questionable and the substitution rate between h and g may arbitrarily change depending on the specific h and g values, (3) the apparent increase in granularity of hg, with respect to h and g, is illusory and misleading. Argument is supported by several examples.

This paper proposes an empirical analysis of several scientists based on their time regularity, defined as the ability of generating an active and stable research output over time, in terms of both quantity/publications and impact/citations. In particular, we empirically analyse three recent bibliometric tools to perform qualitative/quantitative evaluations under the new perspective of regularity. These tools are respectively (1) the PY/CY diagram, (2) the publication/citation Ferrers diagram and triad indicators, and (3) a year-by-year comparison of the scientists’ output (Borda's ranking). Results of the regularity analysis are then compared with those obtained under the classical perspective of overall production.The proposed evaluation tools can be applied to competitive examinations for research position/promotion, as complementary instruments to the commonly adopted bibliometric techniques.► Regularity is defined as the ability of generating an active and stable research output over time. ► Three recent bibliometric tools to evaluate regularity are empirically analysed. ► Results of regularity analysis are compared with those under the perspective of overall production. ► Regularity analysis is complementary to the commonly adopted bibliometric techniques. ► The proposed tools can be applied to competitive examinations for research position/promotion.