SNIP measures contextual citation impact by weighting citations based on the total number of citations in a subject field.
SJR is a prestige metric based on the idea that not all citations are the same. SJR uses a similar algorithm as the Google page rank; it provides a quantitative and a qualitative measure of the journal’s impact.
The Impact Factor measures the average number of citations received in a particular year by papers published in the journal during the two preceding years.
© Thomson Reuters Journal Citation Reports 2015
To calculate the five year Impact Factor, citations are counted in 2014 to the previous five years and divided by the source items published in the previous five years.
© Journal Citation Reports 2015, Published by Thomson Reuters
Precision Engineering - Journal of the International Societies for Precision Engineering and Nanotechnology is devoted to the multidisciplinary study and practice of high accuracy engineering, metrology, and manufacturing. The journal takes an integrated approach to all subjects related to research, design, manufacture, performance validation, and application of high precision machines, instruments, and components, including fundamental and applied research and development in manufacturing processes, fabrication technology, and advanced measurement science. The scope includes precision-engineered systems and supporting metrology over the full range of length scales, from atom-based nanotechnology and advanced lithographic technology to large-scale systems, including optical and radio telescopes and macrometrology.
Precision Engineering was first published in January 1979; since 1986 it has also been known to many of its readers as the Journal of the American Society of Precision Engineering. Now, with effect from January 2000, it assumes a new look, proudly proclaiming itself the Journal of the International Societies for Precision Engineering and Nanotechnology.
In addition to its continuing association with the American Society of Precision Engineering (ASPE), the journal is now associated with two further bodies: the newly established European Society for Precision Engineering and Nanotechnology (EUSPEN) and the Japan Society for Precision Engineering (JSPE), founded in 1933.
For more information about each of these three societies, please visit their home pages: