نتایج جستجو برای: relative isoclinism

تعداد نتایج: 388731  

2017
Hui-Chieh Yu Ni-Yu Su Jing-Yang Huang Shiuan-Shinn Lee Yu-Chao Chang

Periodontitis is one of the most prevalent oral diseases. In this study, we probed the nationwide registered database to assess the time trends of prevalence of periodontitis in Taiwan.A retrospective study was conducted to analyze the registered database compiled by the National Health Insurance provided by the Department of Health, Taiwan, from 1997 to December 2013.We found that the prevalen...

Journal: :Optics letters 2008
Sergey A Ponomarenko Govind P Agrawal

We derive an expression for the lower bound of the phase-space beam quality factor M(2) of an ultrashort pulse. We show that the condition M(2)>or=1 does not, in general, hold for such pulsed beams. Rather, the minimum value of M(2) depends on the pulse spectrum. We also show that M(2) attains minimum only for pulsed beams whose spot size varies with frequency as omega(-1/2), and that the radia...

Journal: :International journal of radiation oncology, biology, physics 1982
E J Hall A M Kellerer H Friede

Journal: :Journal of the National Cancer Institute 1959
N MANTEL W HAENSZEL

The role and limitations of retrospective investigations of factors possibly associated with the occurrence of a disease are discussed and their relationship to forward-type studies emphasized. Examples of situations in which misleading associations could arise through the use of inappropriate control groups are presented. The possibility of misleading associations may be minimized by controlli...

Journal: :Acta Arithmetica 2015

Journal: :SSRN Electronic Journal 2017

Journal: :Journal of Philosophical Logic 2016

Journal: :Proceedings of the Edinburgh Mathematical Society 1992

Journal: :Bulletin of the Belgian Mathematical Society - Simon Stevin 1996

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید