Acknowledgements We are grateful to Maria Claudia Lopez and members of the Faculty of Environmental and Rural Studies at Javeriana University in Bogotá, Colombia who provided outstanding support for our work in the field. At each site, the experiments would not have been possible without the assistance of local community leaders that helped the research team develop credibility with local commu...

FROM time to time in post-mortem reports, a small tumour of the posterior pituitary stalk, called a choristoma, is an incidental finding. Looking through the reports of the Pathology Department of Queen's University, it was possible to find thirty cases of choristoma over the past twenty years. The tumour was first noticed by Boyce and Beadle in 1893, but was called "Choristoma" by Sternberg in...

We present versions of the Frank-Wolfe method for linearly constrained convex programs, in which consecutive search directions are made conjugate. Preliminary computational studies in a MATLAB environment applying pure Frank-Wolfe, Conjugate direction Frank-Wolfe (CFW), Bi-conjugate Frank-Wolfe (BFW) and ”PARTANized” Frank-Wolfe methods to some classical Traffic Assignment Problems show that CF...

zygophyllum atriplicoides is one of the most important rangeland plants that often seen as associated species and rarely seen as the dominant species in ranglands rangelands which is very critical for soil  in starting and ending points of each transect. measured soil properties (included gravel, texture, organic matter, lime, ph and electrical conductivity) and physiography (elevation and slop...

Given a hypergraph and a set of embedded functional dependencies, we investigate the problem of determining the conditions under which we can efficiently generate redundancy-free XML storage structures with as few scheme trees as possible. Redundancy-free XML structures guarantee both economy in storage space and the absence of update anomalies, and having the least number of scheme trees requi...

This paper discusses normalization of relations when the candidate keys of a relation have missing information represented by nulls. The paper shows that when the missing information is of the type " not applicable " or " does not exist, " problems and confusion can arise in normalizing relations. Candidate keys with missing information commonly are found in relations that represent information...

A common approach in designing relational databases is to start with a universal relation schema, which is then decomposed into multiple subschemas. A good choice of subschemas can be determined using integrity constraints defined on the schema, such as functional, multivalued or join dependencies. In this paper we propose and analyze a new normal form based on the idea of minimizing overall st...

Normal forms play a central role in the design of relational databases. Several normal forms for temporal relational databases have been proposed. These definitions are particular to specific temporal data models, which are numerous and incompatible. This paper attempts to rectify this situation. We define a consistent framework of temporal equivalents of the important conventional database des...

location of transit lines and stations, as well as scheduling, provides an essential guide to research problems for all scholars. Although the reader may not agree with each of his problem formulations, Vucbic's consistent and expert expression of problems at various geographic scales, and his review of the current status of their solution in research and practice, provides an essential startin...