Four aspects of factors influencing the accuracy of nondestructive chlorophyll (Chl) and nitrogen (N) measurement in fresh leaves were studied: (1) optimum wavelength (OW) identification; (2) indices development and evaluation; (3) influence of leaf properties; and (4) influence of meter parameters and sampling technique. Results were used to develop indices...
This research addresses sample process variance estimation on continuous domains and for non-probability samples in particular. The motivation for the research is a scenario in which a program has collected non-probability samples for which there is interest in characterizing how much an extrapolation to the domain would vary given similarly...
Software maintenance accounts for a large portion of the software development cost, particularly the process of updating programs either to adapt for requirement change or to enhance design or efficiency. Currently, program updates are generally performed manually by programmers using text editors. This is an unreliable
method because syntax and...
Previous attempts to understand the factors affecting the energetic cost of locomotion have found a direct link between the energetic cost and the mechanical work done during periods when the limb is in contact with the ground. However, when the limb is not in contact with the ground during the...
Forest growth models in the Pacific Northwest are predominantly empirical. Predictions of yield under alternative silvicultural regimes cannot rely completely on field trials; yet empirical growth models are often inadequate for extrapolating untested regimes and genotypes. The limitations of current models include (1) long time-steps (e.g. 5-10 years); (2) insufficient...
Once considered the largest wetland in Central Asia, the Mesopotamian Marshlands of Southeastern Iraq have nearly disappeared. Various hydrological projects by the Iraqi government and dam construction in the region have nearly destroyed these once rich freshwater wetlands by over 90%. With the launching of Operation Iraqi Freedom recent attempts...
Dramatic declines in several groundfish populations have occurred along
the U.S. West Coast during the last decade (PFMC 1999, Sampson 1997,
Ralston 1998, Bloeser 1999). One problem exacerbating these declines is
insufficient stock assessments, especially for species of west coast rockfish
(Family Scorpaenidae, Genus Sebastes) which comprise the core of...
Air travel presents several problems for passengers with disabilities.
One in particular is how they get from their wheelchair and to an aircraft seat.
The commonly used manual transfer method is hazardous to the assistants
and the passenger. There are other alternatives, but they have plenty of room
for improvement....
From a landscape ecology perspective, meadows are often seen as landscapes in
transition. Succession and change in meadows may be investigated by considering the
physical and anthropogenic factors that influence the landscape through time. What is
often unknown is how changes occur and how physical and anthropogenic factors
contribute to...
How complex traits evolve continues to be a major focus of evolutionary
investigation. A current topic of debate is the hypothesis that the phenotypic
integration of complex traits gives rise to evolutionary constraints. I studied two color
traits in the common garter snake, Thamnophis sirtalis, that show a high level...