Study of multiple hologram recording in lithium niobate

The results of detailed experimental and theoretical considerations relating to multiple hologram recording in lithium niobate are reported. The following problem areas are identified and discussed: (1) the angular selectivity of the stored holograms, (2) interference effects due to the crystal surfaces, (3) beam divergence effects, (4) material recording sensitivity, and (5) scattered light from material inhomogeneities

Decision Table Formulation of The 1969 Aisc Specification

The American Institute of Steel Constructio

Study of multiple hologram recording in lithium niobate

The results of a number of theoretical and experimental studies relating to multiple hologram recording in lithium niobate are reported. The analysis of holographic gratings stored in lithium niobate has been extended to cover a more realistic range of physical situations. A new successful dynamic (feedback) theory for describing recording, nondestructive reading, erasure, enhancement, and angular sensitivity has been developed. In addition, the possible architectures of mass data storage systems have been studied

Hydrologic Data for Urban Studies in the Austin, Texas Metropolitan Area, 1980

This report includes drainage basin maps and information from a specific storm (May 12, 1980) for the 23rd and 38th street Waller Creek locations.Waller Creek Working Grou

Working Paper 31: Climate Change Impacts on Bark Beetle Outbreaks and the Impact of Outbreaks on Subsequent Fires.

The Insect Bark beetles are small insects that can have profound impacts on forests. While some species of bark beetles primarily attack trees that are recently dead or dying, others attack live, vigorous trees and can cause tree mortality across extensive areas. The Southwest is home to multiple species of bark beetles (Gaylord et al. 2006, Williams et al. 2008). In southwestern ponderosa pine forests the most notable bark beetle species belong to the genus Ips or Dendroctonus. Ecological Role and Impacts Bark beetles and fire share similar roles in southwestern ponderosa pine forests. Similar to fire, bark beetles are natural disturbance agents and help with nutrient redistribution. Tree mortality from bark beetles helps with snag formation, providing vital habitat for cavity nesting birds and bats, among other wildlife. Bark beetles are a food source for other insects and birds. At low bark beetle populations, tree mortality ranges from individual trees to small groups of trees leading to gap formation and increasing forest heterogeneity. Epidemics, or outbreaks, are also part of the natural cycle. In some ecosystems, such as mountain pine beetle in lodgepole pine, the forests are homogenized after these outbreaks, helping to perpetuate lodgepole pine stands (Brown 1975). Historically, epidemics would subside due to excessively cold temperatures or because suitable host material (tree species or preferred diameter range) becomes depleted. Current bark beetle outbreaks in some forest systems are considered unprecedented (Raffa et al. 2008, Bentz et al. 2009). Recent outbreaks appear to be driven by warmer/drier climate, an abundance of overstocked and homogeneous stands caused by past management decisions, or a combination of these and other factors (Raffa et al. 2008, Bentz et al. 2010, Fettig et al. 2013). In essence, large-scale outbreaks are a result of many of the same factors driving catastrophic fires and, consequently, both disturbance agents are having impacts on ecosystems that are often outside of their historic range of variability

Back-up Server for Computer Science Department

Because Western Kentucky University does not maintain a back-up system for its departments, the Computer Science Department has implemented its own. Using Bacula software on a Unix server, files from faculty desktop computers and servers are backed up to a tape drive on a daily basis. The server is protected from outside threats with a carefully configured firewall script. This paper explains how both the firewall and the back-up software were implemented and how successful that implementation has been

Working Paper 30: Impact of Forest Restoration Treatments on Southwestern Ponderosa Pine Tree Resistance to Bark Beetles

Insects can have a wide-range of both positive and negative effects on forest ecosystems. Positive impacts include serving as pollinators, creating snags for cavity nesting birds and bats, helping to increase forest heterogeneity, and aiding in decomposition and nutrient cycling. Negative impacts can range from relatively minor impacts at the individual tree level, such as reductions in growth or form defects, to landscape-level tree mortality (Coulson and Witter 1984, Raffa et al. 2008). In the ponderosa pine forests of the southwestern United States, the bark beetle has been the insect most often associated with widespread tree mortality. Restoration efforts in ponderosa pine ecosystems have the overarching goal of making these forests more healthy and resilient by reducing fuel loads and restoring ecosystem functions. Stand restoration in these ecosystems usually involves varying intensities of thinning or prescribed burning treatments or, more often, some combination of both. These same treatments may also alter tree susceptibility to disturbance events, such as insect attacks and wildfire. This working paper will highlight current research about the effects of restoration treatments on ponderosa pine tree resistance/susceptibility to bark beetles

Love and Valor : Waltzes

https://digitalcommons.library.umaine.edu/mmb-ps/2764/thumbnail.jp