Current database systems apply access control mostly on tables and columns.
However, many applications require access control on individual rows in database
tables. Therefore, we have implemented a row-based access control mechanism. In
our model for access control, object groups, in addition to user groups, are used to
reduce the...
Scientific inquiry in K-12 classrooms tends to be procedural, lacking opportunities for students to gain understanding of how scientific knowledge is constructed through reflection, debate, and argument. Limited opportunity to develop scientific argumentation skills prevents students from practicing the scientific thinking needed to understand the nature of scientific knowledge and...
In many areas of engineering and applied mathematics, spectral methods provide very powerful tools for solving and analyzing problems. For instance, large to extremely large sizes of numbers can efficiently be multiplied by using discrete Fourier transform and convolution property. Such computations are needed when computing π to millions of...
Lingcod are an overexploited fish species in the Pacific Northwest and although there has been extensive study of the habitat requirements of adults, particularly during spawning, relatively little is known regarding the habitat requirements of post-settlement juveniles. Many juvenile fish use structural components of habitat to alleviate the risk of...
Farmlands, grasslands, and savannas in semi-arid sub-Sahelian Africa have the potential to store
carbon (C) in soil. There is a great need to manage ecosystems to increase C storage in semipermanent
soil pools. This will improve soil quality, impede desertification and by reducing
atmospheric CO₂ levels, will slow climate change....