INCORPORATING UNCERTAINTY IN THE ANALYSIS OF OPTIMAL BEEF-FORAGE PRODUCTION SYSTEMS

A risk programming model was developed to evaluate the tradeoffs between risk and expected returns in beef-forage production systems. The specification represents nutrient and intake considerations when allocating forage among cattle enterprises; it also incorporates the various sources of risk facing livestock producers. Efficient ranch organizations were derived for a representative eastern Oklahoma ranch using MOTAD and Target-MOTAD formulations. Diversification of forage enterprises, introduction of cow-calf enterprises, and retained ownership of weaned calves were identified as important responses to reductions in acceptable levels of risk. Results also indicated efficient ranch plans to be sensitive to the risk criteria and producer's willingness to accept risk.Livestock Production/Industries, Risk and Uncertainty,

Residency Status and Discrimination among Immigrants in Minnesota

Discrimination and other social injustices experienced by immigrants in the United States are well documented in the literature. Few studies, however, have investigated the relationship between residency status and discrimination. This exploratory, qualitative study investigated the relationship between residency status and discrimination among immigrants in Minnesota. The author conducted semi-structured interviews with seven immigrants and five professionals (lawyers and social workers) who provide direct services to immigrants. The study operated under the assumption that immigrants with more precarious residency status (undocumented immigrants, for example), would experience greater discrimination than immigrants with more stable residency status (refugees or lawful permanent residents, for example). The qualitative data suggest that undocumented immigrants do not necessarily experience greater discrimination than immigrants with more stable residency status. Other variables such as race, national origin, or simply being an immigrant regardless of residency status seem to contribute to discrimination experiences as well. Further research is needed to better understand the relationship between these variables

Spectral identification/elimination of molecular species in spacecraft glow

Computer models of molecular electronic and vibrational emission intensities were developed. Known radiative emission rates (Einstein coefficients) permit the determination of relative excited state densities from spectral intensities. These codes were applied to the published spectra of glow above shuttle surface and to the Spacelab 1 results of Torr and Torr. The theoretical high-resolution spectra were convolved with the appropriate instrumental slit functions to allow accurate comparison with data. The published spacelab spectrum is complex but N2+ Meinel emission can be clearly identified in the ram spectrum. M2 First Positive emission does not correlate well with observed features, nor does the CN Red System. Spectral overlay comparisons are presented. The spectrum of glow above shuttle surfaces, in contrast to the ISO data, is not highly structured. Diatomic molecular emission was matched to the observed spectral shape. Source excitation mechanisms such as (oxygen atom)-(surface species) reaction product chemiluminescence, surface recombination, or resonance fluorescent re-emission will be discussed for each tentative assignment. These assignments are the necessary first analytical step toward mechanism identification. Different glow mechanisms will occur above surfaces under different orbital conditions

High frequency diffraction of an electromagnetic plane wave by an imperfectly conducting rectangular cylinder

Copyright @ 2011 IEEEWe shall consider the the problem of determining the scattered far wave field produced when a plane E-polarized wave is incident on an imperfectly conducting rectangular cylinder. By using the the uniform asymptotic solution for the problem of the diffraction of a plane wave by a right-angled impedance wedge, in conjunction with Keller's method, the a high frequency far field solution to the problem is given

Evaluation of trends in derived snowfall and rainfall across Eurasia and linkages with discharge to the Arctic Ocean

To more fully understand the role of precipitation in observed increases in freshwater discharge to the Arctic Ocean, data from a new archive of bias-adjusted precipitation records for the former USSR (TD9813), along with the CRU and Willmott-Matsuura data sets, were examined for the period 1936–1999. Across the six largest Eurasian river basins, snowfall derived from TD9813 exhibits a strongly significant increase until the late 1950s and a moderately significant decrease thereafter. A strongly significant decline in derived rainfall is also noted. Spatially, snowfall increases are found primarily across north-central Eurasia, an area where the rainfall decreases are most prominent. Although no significant change is determined in Eurasian-basin snowfall over the entire 64 year period, we note that interpolation from early, uneven station networks causes an overestimation of spatial precipitation, and that the local snowfall trends determined from gridded TD9813 data are likely underestimated. Yet, numerous uncertainties in historical Arctic climate data and the sparse, irregular nature of Arctic station networks preclude a confident assessment of precipitation-discharge linkages during the period of reported discharge trends

A review of climate change impacts on urban soil functions with examples and policy insights from England, UK

As of 2010, more than half of the global population resides in urban areas and relies to some extent on the functions, services and natural capital provided by urban soils. Greater extremes in climate predicted for the coming decades will impact on these urban soil functions to varying degrees. We provide an inventory of urban soil functions based on an extension to the typology of the Millennium Ecosystem Assessment (i.e. we added a carrying function to those of supporting, regulating, provisioning and cultural) and review the climate drivers which are likely to have the most significant impacts upon them, using urban soils of England as an exemplar. We identify knowledge gaps, in areas such as carbon cycling and storage, disease regulation and cultural services. We assess adaptation measures which may ameliorate these potential, climate change-related impacts including changes in construction practices, developments in green architecture and development proposals under the planning regime. We discuss the lack of policies relating to urban soils and the problem associated with monitoring their functions, as is often the case, when large quantities of soil are removed and replaced leading to major transformation of soil properties which may be un-related to pedogenic processes

Ultraviolet absorption: Experiment MA-059

A technique devised to permit the measurement of atmospheric species concentrations is described. This technique involves the application of atomic absorption spectroscopy and the quantitative observation of resonance fluorescence in which atomic or molecular species scatter resonance radiation from a light source into a detector. A beam of atomic oxygen and atomic nitrogen resonance radiation, strong unabsorbable oxygen and nitrogen radiation, and visual radiation was sent from Apollo to Soyuz. The density of atomic oxygen and atomic nitrogen between the two spacecraft was measured by observing the amount of resonance radiation absorbed when the line joining Apollo and Soyuz was perpendicular to their velocity with respect to the ambient atmosphere. Results of postflight analysis of the resonance fluorescence data are discussed

Intermittent Small Baseline Subset (ISBAS) monitoring of land covers unfavourable for conventional C-band InSAR: proof-of-concept for peatland environments in North Wales, UK

This paper provides a proof-of-concept for the use of the new Intermittent Small Baseline Subset (ISBAS) approach to study ground elevation changes in areas of peat and organic soils in north Wales, which are generally, unfavourable for conventional C-band interferometric applications. A stack of 53 ERS-1/2 C-band SAR scenes acquired between 1993 and 2000 in descending mode was processed with both the standard low-pass SBAS method and ISBAS. The latter revealed exceptional improvements in the coverage of ground motion solutions with respect to the standard approach. The number of identified coherent and intermittently coherent pixels increased by a factor of 26 with respect to the SBAS solution, and extended the coverage of results across unfavourable land covers, particularly for coniferous woodland, bog, acid grassland and heather. The greatest increase was achieved over coniferous woodland, which showed ISBAS/SBAS pixel density ratios above 300. Despite the intermittent nature of the ISBAS solutions, ISBAS provided velocity standard errors generally below 1-1.5 mm/yr, thus preserving good quality of the estimated ground motion rates