Vertical datum is a reference system used for specifying the elevation of specific points on or near the Earth. Precise and accurate definition and realization of vertical references are, therefore, crucial to ensure consistency between height measurements. The vertical datums can be divided into two categories: 1) vertical geodetic datums...
An ultra low power crystal oscillator that provides a frequency reference for battery
powered timekeeping applications is presented. An amplitude control circuit is employed to ensure that minimum current is consumed. A subthreshold voltage regulator provides a supply voltage for the oscillator with minimum current consumption. The oscillator and regulator...
Using the historical range of forest conditions as a reference for managing landscapes has been proposed as a "coarse-filter" approach to biodiversity conservation. By emulating historical disturbance processes, it is thought that forest management can produce forest composition and structure similar to the conditions that once supported the native biota....
Stream temperature research relies on reference frames in which to project data. An important decision in the project design is which frame of reference to use. This aspect of research planning is not always given the consideration of thought that would lead to the best decision. In this thesis, two...
The U.S. Department of Energy (DOE) Order 458.1 states that the compliance with the DOE annual dose limit of 1 mSv (100 mrem) to a member of the public may be demonstrated by calculating dose to the maximally exposed individual (MEI) or to a representative person. Historically, the MEI concept...
Pollution by pesticides is a ubiquitous concern for wildlife. The effects of
pesticides are especially concerning in aquatic environments, which are particularly
vulnerable as they have several exposure routes for the influx of chemicals. These
effects are of particular concern as biodiversity loss reaches unprecedented rates. This
includes recent declines...
Tidal wetland channels provide rearing habitat for juvenile Chinook salmon as they emigrate from freshwater habitat and prepare to enter the ocean. Widespread diking and drainage of estuarine marshes for agricultural and urban development may have contributed to a decline in salmon abundance in the Pacific Northwest, prompting efforts to...
In this thesis, the spatial patterns of vegetation and soils of reference and restored tidal marshes were compared to determine the extent to which restored sites differ from the reference site after 40 years of restoration. Vegetation surveys of 1m x 1m plots were conducted along previously-established transects of salt...
Radiation protection has historically been from a human protection approach, therefore many studies have neglected the potential dose contribution from the gastrointestinal tract (GIT) in animal studies. The International Commission on Radiological Protection (ICRP) utilized simplified geometric shapes with Dose Conversion Factors (DCF) based on homogenized models for the trout...
Aligning Real-Time Networks (RTNs) with the National Spatial Reference System (NSRS) is crucial to ensure accuracy, consistency, interoperability, and long-term data integrity for geospatial applications. However, the effectiveness of different alignment methods as well as the need for monitoring approaches to maintain alignment consistency with the NSRS have not yet...