scholarly journals Operational Models for Reputation Servers

Author(s):  
D. W. Chadwick
Keyword(s):  
2021 ◽  
pp. 146144482199864
Author(s):  
Kathrin Friedrich ◽  
A S Aurora Hoel

Interventional digital media applications such as robotic surgery, remote-controlled vehicles or wearable tracking devices pose a challenge to media research methodologically as well as conceptually. How do we go about analyzing operational media, where human and non-human agencies intertwine in seemingly inscrutable ways? This article introduces the method of o perational analysis to systematically observe and critically analyze such situated, interventional and multilayered entanglements. Against the background of ongoing efforts to develop operational models for understanding digital media, the method of operational analysis conceptually ascribes to media technologies a real efficacy by approaching them as adaptive mediators. As an operational middle-range approach, it allows to integrate theoretical discussions with considerations of the situatedness, directedness, and task-orientation of operational media. The article presents an analytical toolbox for observing and analyzing digital media operations while simultaneously testing it on a particular application in robotic radiosurgery.


2015 ◽  
Vol 21 (6) ◽  
pp. 662-666
Author(s):  
V. Bancone

2010 ◽  
Vol 138 (12) ◽  
pp. 4542-4560 ◽  
Author(s):  
John E. Janowiak ◽  
Peter Bauer ◽  
Wanqiu Wang ◽  
Phillip A. Arkin ◽  
Jon Gottschalck

Abstract In this paper, the results of an examination of precipitation forecasts for 1–30-day leads from global models run at the European Centre for Medium-Range Weather Forecasts (ECMWF) and the National Centers for Environmental Prediction (NCEP) during November 2007–February 2008 are presented. The performance of the model precipitation forecasts are examined in global and regional contexts, and results of a case study of precipitation variations that are associated with a moderate to strong Madden–Julian oscillation (MJO) event are presented. The precipitation forecasts from the ECMWF and NCEP operational prediction models have nearly identical temporal correlation with observed precipitation at forecast leads from 2 to 9 days over the Northern Hemisphere during the cool season, despite the higher resolution of the ECMWF operational model, while the ECMWF operational model forecasts are slightly better in the tropics and the Southern Hemisphere during the warm season. The ECMWF Re-Analysis Interim (ERA-Interim) precipitation forecasts perform only slightly worse than the NCEP operational model, while NCEP’s Climate Forecast System low-resolution coupled model forecasts perform the worst among the four models. In terms of bias, the ECMWF operational model performs the best among the four model forecasts that were examined, particularly with respect to the ITCZ regions in both the Atlantic and Pacific. Local temporal correlations that were computed on daily precipitation totals for day-2 forecasts against observations indicate that the operational models at ECMWF and NCEP perform the best during the 4-month study period, and that all of the models have low to insignificant correlations over land and over much of the tropics. They perform the best in subtropical and extratropical oceanic regions. Also presented are results that show that striking improvements have been made over the past two decades in the ability of the models to represent precipitation variations that are associated with MJO. The model precipitation forecasts exhibit the ability to characterize the evolution of precipitation variations during a moderate–strong period of MJO conditions for forecast leads as long as 10 days.


Author(s):  
Michael Batty

AbstractThis introductory chapter provides a brief overview of the theories and models that constitute what has come to be called urban science. Explaining and measuring the spatial structure of the city in terms of its form and function is one of the main goals of this science. It provides links between the way various theories about how the city is formed, in terms of its economy and social structure, and how these theories might be transformed into models that constitute the operational tools of urban informatics. First the idea of the city as a system is introduced, and then various models pertaining to the forces that determine what is located where in the city are presented. How these activities are linked to one another through flows and networks are then introduced. These models relate to formal models of spatial interaction, the distribution of the sizes of different cities, and the qualitative changes that take place as cities grow and evolve to different levels. Scaling is one of the major themes uniting these different elements grounding this science within the emerging field of complexity. We then illustrate how we might translate these ideas into operational models which are at the cutting edge of the new tools that are being developed in urban informatics, and which are elaborated in various chapters dealing with modeling and mobility throughout this book.


2015 ◽  
Vol 247 (3) ◽  
pp. 685-698 ◽  
Author(s):  
Yulan Wang ◽  
Stein W. Wallace ◽  
Bin Shen ◽  
Tsan-Ming Choi

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