Collaborative research: earth system curator: spanning the gap between models and datasets

Issued as final reportNational Science Foundation (U.S.

Development of a nonstationary flow device for an atmospheric boundary layer wind tunnel

Iowa State University researchers are in the process of developing a new wind tunnel. This tunnel will be able to perform a wide range of tests. It will not only be used in an aerodynamic (Aero) test section configuration, but also in an atmospheric boundary layer (ABL) type configuration. It will be able to create a model of the turbulent boundary layer that all structures in the atmosphere are submersed in. The tunnel is designed to utilize both closed return as well as open return tunnel configurations. This will enable the tunnel to reap the benefits of both types of tunnels. Currently most of the ABL studies rely on the assumption that atmospheric velocity variations are adequately modeled by stationary mean and turbulent flow properties. The ISU Aero/ABL tunnel will be able to develop non-stationary flows to help better study and understand this type of phenomena. The primary concern and area of research reported here has been to develop this non-stationary flow device by modeling and testing the design. The results shown reflect that a 107% gust can be achieved by the model, but with some changes to the design, a higher magnitude gust can be achieved

Irregular dynamics of cellular blood flow in a model microvessel

The flow of red blood cells within cylindrical vessels is complex and irregular, so long as the vessel diameter is somewhat larger than the nominal cell size. Long-time-series simulations, in which cells flow 105 vessel diameters, are used to characterize the chaotic kinematics, particularly to inform reduced-order models. The simulation model used includes full coupling between the elastic red blood cell membranes and surrounding viscous fluid, providing a faithful representation of the cell-scale dynamics. Results show that the flow has neither classifiable recurrent features nor a dominant frequency. Instead, its kinematics are sensitive to the initial flow configuration in a way consistent with chaos and Lagrangian turbulence. Phase-space reconstructions show that a low-dimensional attractor does not exist, so the observed long-time dynamics are effectively stochastic. Based on this, a simple Markov chain model for the dynamics is introduced and shown to reproduce the statistics of the cell positions

The Regulation of Specialty Policies in Life Insurance

Every entrepreneur is vitally concerned with selling methods. Success depends upon sales. Sales depend upon desire for the product. Desire for most products, including life insurance, is not inherent but is created by the efforts of the entrepreneur. In the case of life insurance, an effective job of creating the desire, i.e., of selling, is usually necessary to convince a prospective insurance buyer that over a long period he should allocate a significant portion of his income to the purchase of an intangible such as life insurance

Encountering authority and avoiding trouble: Young migrant men’s narratives of negotiation in Europe

Drawing on data from seven European countries (Czech Republic, Finland, France, Germany, Ireland, Italy and the United Kingdom), this article seeks to identify how young migrant men engage with authority and avoid conflict against a backdrop of increasing hostility towards migrants in many European countries. As this article contends, even those with permanent residency status in the host country often find themselves having to justify their legitimacy to carry out daily tasks, resulting in many young male migrants living with feelings of perpetual insecurity. As such, a number of coping strategies are employed by young migrant men in order to assuage such feelings and mitigate potential risks. Focusing on the lived experiences of this group, as described in narrative interviews, our study found that many young migrant men are required to enter into negotiations with authority figures, where there is a considerable power differential. Acting as risk assessors, they find themselves forced to navigate complex and challenging social relations and support networks. We show how self-limiting behaviour intended to avoid or control interactions with authority and the negotiations conducted to minimize the risk of ‘trouble’ by young migrant men not only are problematic in the context of day-to-day activities but can very often have a detrimental impact on their lives

Detection of Baryonic Acoustic Oscillations in the Matter Power Spectrum

Using the spectra of 22,923 high-redshift quasars from the Baryon Oscillation Spectrosocpic Survey (BOSS) subset of the Sloan Digital Sky Survey (SDSS), the authors detect evidence of the primordial baryonic acoustic oscillations (BAOs) in the matter power spectrum. The detection further endorses the currently accepted Lambda-CDM model of cosmology based upon the existence of dark energy (Lambda) and cold dark matter (CDM). Additionally, the use of the continuous wavelet transform to calculate the power spectrum has many advantages over traditional Fourier methods and independently corroborates previous detections

Gr\"obner Bases and Nullstellens\"atze for Graph-Coloring Ideals

We revisit a well-known family of polynomial ideals encoding the problem of graph-$k$-colorability. Our paper describes how the inherent combinatorial structure of the ideals implies several interesting algebraic properties. Specifically, we provide lower bounds on the difficulty of computing Gr\"obner bases and Nullstellensatz certificates for the coloring ideals of general graphs. For chordal graphs, however, we explicitly describe a Gr\"obner basis for the coloring ideal, and provide a polynomial-time algorithm.Comment: 16 page

Geology and geochronology of the Avawatz Mountains, San Bernardino County, California

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Science, 1981.Microfiche copy available in Archives and ScienceIncludes bibliographies.by Jon Eric Spencer.Ph.D