160 research outputs found
Experiments on waves trapped over the continental slope and shelf in a continuously stratified rotating ocean, and their incidence on a canyon
Continental margins form a waveguide for topographic Rossby waves, which can be trapped to the bottom by continuous stratification and concentrated over the continental slope while propagating along the coast. We present results of laboratory wave simulations designed to keep as many dimensionless numbers (Rossby, Burger, normalized frequency, wave steepness, geometrical, Ekman, and Reynolds) as possible similar to those of coastal-trapped waves, such as are observed in coastal regions around the world. The 13-m diameter rotating tank is salt-stratified and a continental slope joins a shallow shelf region along the outer tank circumference to a deep central region. The velocity field is measured using a correlation-based digital particle image velocimetry technique at several depths. Current ellipses downstream from subinertial forcing indicate along-isobath propagation with energy concentrated at depth and three-dimensional structure in agreement with a numerical wave solution calculated using the experimental geometry, rotation rate, and buoyancy frequency. Contrasting the inviscid wave solution, experimental flow shows an asymmetry with positive time-mean uv correlations (u across isobaths toward deep water, v along isobaths with shallow water to the left), and phase variations perpendicular to isobaths with flow near the shelf break leading that farther inshore and offshore. Both of these attributes have been seen previously in ocean observations and are interpreted as the signature of frictional influences based on stratified slope-Kelvin wave behavior. When incident on a canyon that indents the slope and shelf, a wave propagates in to and out of it along isobaths while remaining concentrated over the sloping topography with only weakly modified amplitude and phase structure. Based on the limited range of parameter space studied, the implication is that alongshore wave propagation will remain largely unmodified by natural corrugations in the slope and shelf and loss of energy by scattering will be weak
New Victory Mining Company Avon, Powell County, Montana
Mr. L.D. McClean and Mr. A. Schemel, officers of the New Victory Mining Company, requested an examination of the company\u27s properties near Avon, Montana. Following this request Mr. E. Renouard Jr., and Mr. E.P. Shea visited the properties on March 2nd and 3rd, 1935, and submit herewith the following report
LANDSCAPE IMPACT ASSESSMENT OF SDG2 DEVELOPMENT PROJECTS USING REMOTE SENSING AND UNSUPERVISED CONTROL SITE SELECTION
As part of its objective to achieve Zero Hunger under SDG2 the United Nations World Food Programme, in partnership with Governments, NGOs and other UN agencies, supports food insecure communities to increase natural resource availability and improve their management. This is done mostly through the building and rehabilitation of soil and water conservation assets (e.g., small dams, weirs, landscape restoration) and structures that increase productivity (e.g., vegetable gardens, irrigation canals). To adequately monitor these activities around the globe simultaneously, remote sensing was found to be an adequate tool. This study introduces the use of high-resolution satellite imagery, and more specifically NDVI derived from the Landsat series to verify and quantify the impact of such development projects. In total 121 projects in 10 countries and six different climate zones were analyzed using a pre- and post-implementation comparison and a Before-After Control Impact (BACI) study considering randomly selected control sites. Both approaches were found to show robust results throughout the different countries, project types and climate zones. 67% of all projects showed significant improvements in vegetation conditions during the wet seasons only three years after the implementation. Using the proposed workflow based on Python scripting and cloud computing of satellite data, fast and robust analyses can be achieved, while assuring constant data quality
ART: A machine learning Automated Recommendation Tool for synthetic biology
Biology has changed radically in the last two decades, transitioning from a descriptive science into a design science. Synthetic biology allows us to bioengineer cells to synthesize novel valuable molecules such as renewable biofuels or anticancer drugs. However, traditional synthetic biology approaches involve ad-hoc engineering practices, which lead to long development times. Here, we present the Automated Recommendation Tool (ART), a tool that leverages machine learning and probabilistic modeling techniques to guide synthetic biology in a systematic fashion, without the need for a full mechanistic understanding of the biological system. Using sampling-based optimization, ART provides a set of recommended strains to be built in the next engineering cycle, alongside probabilistic predictions of their production levels. We demonstrate the capabilities of ART on simulated data sets, as well as experimental data from real metabolic engineering projects producing renewable biofuels, hoppy flavored beer without hops, and fatty acids. Finally, we discuss the limitations of this approach, and the practical consequences of the underlying assumptions failing
Ty1-copia elements reveal diverse insertion sites linked to polymorphisms among flax (Linum usitatissimum L.) accessions
Justice and Corporate Governance: New Insights from Rawlsian Social Contract and Senâs Capabilities Approach
By considering what we identify as a problem inherent in the ânature of the firmââthe risk of abuse of authorityâwe propound the conception of a social contract theory of the firm which is truly Rawlsian in its inspiration. Hence, we link the social contract theory of the firm (justice at firmâs level) with the general theory of justice (justice at societyâs level). Through this path, we enter the debate about whether firms can be part of Rawlsian theory of justice showing that corporate governance principles enter the âbasic structure.â Finally, we concur with Senâs aim to broaden the realm of social justice beyond what he calls the âtranscendental institutional perfectionismâ of Rawlsâ theory. We maintain the contractarian approach to justice but introduce Senâs capability concept as an element of the constitutional and post-constitutional contract model of institutions with special reference to corporate governance. Accordingly, rights over primary goods and capabilities are (constitutionally) granted by the basic institutions of society, but many capabilities have to be turned into the functionings of many stakeholders through the operation of firms understood as post-constitutional institutional domains. The constitutional contract on the distribution of primary goods and capabilities should then shape the principles of corporate governance so that at post-constitutional level anyone may achieve her/his functionings in the corporate domain by exercising such capabilities. In the absence of such a condition, post-constitutional contracts would distort the process that descends from constitutional rights and capabilities toward social outcomes
Stress analysis of different configurations of 3 implants to support a fixed prosthesis in an edentulous jaw
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