University of Iowa

About: University of Iowa is a education organization based out in Iowa City, Iowa, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 49229 authors who have published 109171 publications receiving 5021465 citations. The organization is also known as: UI & The University of Iowa.

UbiCrawler: a scalable fully distributed web crawler

Abstract: We report our experience in implementing UbiCrawler, a scalable distributed Web crawler, using the Java programming language. The main features of UbiCrawler are platform independence, linear scalability, graceful degradation in the presence of faults, a very effective assignment function (based on consistent hashing) for partitioning the domain to crawl, and more in general the complete decentralization of every task. The necessity of handling very large sets of data has highlighted some limitations of the Java APIs, which prompted the authors to partially reimplement them.

Description and performance of track and primary-vertex reconstruction with the CMS tracker

Abstract: A description is provided of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices. Despite the very hostile environment at the LHC, the performance obtained with these algorithms is found to be excellent. For tt events under typical 2011 pileup conditions, the average track-reconstruction efficiency for promptly-produced charged particles with transverse momenta of p_T > 0.9GeV is 94% for pseudorapidities of |η| < 0.9 and 85% for 0.9 < |η| < 2.5. The inefficiency is caused mainly by hadrons that undergo nuclear interactions in the tracker material. For isolated muons, the corresponding efficiencies are essentially 100%. For isolated muons of p_T = 100GeV emitted at |η| < 1.4, the resolutions are approximately 2.8% in p_T, and respectively, 10μm and 30μm in the transverse and longitudinal impact parameters. The position resolution achieved for reconstructed primary vertices that correspond to interesting pp collisions is 10–12μm in each of the three spatial dimensions. The tracking and vertexing software is fast and flexible, and easily adaptable to other functions, such as fast tracking for the trigger, or dedicated tracking for electrons that takes into account bremsstrahlung.

The Theory of Purposeful Work Behavior: The Role of Personality, Higher-Order Goals, and Job Characteristics

Abstract: The theory of purposeful work behavior integrates higher-order implicit goals with principles derived from the Five-Factor Model (FFM) of personality and the expanded job characteristics model to explain how traits and job characteristics jointly and interactively influence work outcomes. The core principle of the theory is that personality traits initiate purposeful goal strivings, and when the motivational forces associated with job characteristics act in concert with these purposeful motivational strivings, individuals experience the psychological state of experienced meaningfulness. In turn, experienced meaningfulness triggers task-specific motivation processes that influence the attainment of work outcomes. We describe testable propositions derived from the theory and discuss directions for future research.