Use of Navigation Beacons to Support Lunar Vehicle Operations

To support a wide variety of lunar missions in a condensed regime, solutions are needed outside of the use of Earth-based orbit determination. This research presents an alternate approach to in-situ navigation through the use of beacons, similar to that used on Earth as well as under technology development efforts. An overview of the current state of navigation aids included as well as discussion of the Lunar Node 1 payload being built at NASA/Marshall Space Flight Center. Expected navigation results of this beacon payload for planned operation from the lunar surface are provided. Applications of navigation beacons to multiple stages of the proposed human lunar landing architecture are given, with initial analysis showing performance gains from the use of this technology. This work provides a starting point for continued analysis and design, laying out the foundation of how navigation beacons can be incorporated into the architecture to enable continued analysis, design, and future expanded capability

A Reciprocity Theorem for Monomer-Dimer Coverings

The problem of counting monomer-dimer coverings of a lattice is a longstanding problem in statistical mechanics. It has only been exactly solved for the special case of dimer coverings in two dimensions. In earlier work, Stanley proved a reciprocity principle governing the number $N(m,n)$ of dimer coverings of an $m$ by $n$ rectangular grid (also known as perfect matchings), where $m$ is fixed and $n$ is allowed to vary. As reinterpreted by Propp, Stanley's result concerns the unique way of extending $N(m,n)$ to $n < 0$ so that the resulting bi-infinite sequence, $N(m,n)$ for $n \in {Z}$, satisfies a linear recurrence relation with constant coefficients. In particular, Stanley shows that $N(m,n)$ is always an integer satisfying the relation $N(m,-2-n) = \epsilon_{m,n}N(m,n)$ where $\epsilon_{m,n} = 1$ unless $m\equiv$ 2(mod 4) and $n$ is odd, in which case $\epsilon_{m,n} = -1$. Furthermore, Propp's method is applicable to higher-dimensional cases. This paper discusses similar investigations of the numbers $M(m,n)$, of monomer-dimer coverings, or equivalently (not necessarily perfect) matchings of an $m$ by $n$ rectangular grid. We show that for each fixed $m$ there is a unique way of extending $M(m,n)$ to $n < 0$ so that the resulting bi-infinite sequence, $M(m,n)$ for $n \in {Z}$, satisfies a linear recurrence relation with constant coefficients. We show that $M(m,n)$, a priori a rational number, is always an integer, using a generalization of the combinatorial model offered by Propp. Lastly, we give a new statement of reciprocity in terms of multivariate generating functions from which Stanley's result follows.Comment: 13 pages, 12 figures, to appear in the proceedings of the Discrete Models for Complex Systems (DMCS) 2003 conference. (v2 - some minor changes

Figure dell’“infermità etica”: Allwill e Woldemar nella lettura di Hegel

In his works, and especially in the Phenomenology of Spirit, Hegel often uses literary references. Among them, we can find also some characters that, in Hegel’s view, embody a worst aspect of the modern subject, “the ethical infirmity”, the inability to act, to realize themselves objectifying their inner determinations. Characters of this kind are Allwill and Woldemar, protagonists of two homonymous novels of Jacobi, that Hegel critically analyzes in Faith and Knowledge. Through the Hegelian analysis of these two literary figures, we will try to highlight the features and causes of this “ethical infirmity”, showing how Hegel see it as a one of the diseases to which it is structurally exposed the modern subjectivity

Spectral properties of single gold nanoparticles in close proximity to biological fluorophores excited by 2-photon excitation

Metallic nanoparticles (NPs) are able to modify the excitation and emission rates (plasmonic enhancement) of fluorescent molecules in their close proximity. In this work, we measured the emission spectra of 20 nm Gold Nanoparticles (AuNPs) fixed on a glass surface submerged in a solution of different fluorophores using a spectral camera and 2-photon excitation. While on the glass surface, we observed the presence in the emission at least 3 components: i) second harmonic signal (SHG), ii) a broad emission from AuNPS and iii) fluorescence arising from fluorophores nearby. When on the glass surface, we found that the 3 spectral components have different relative intensities when the incident direction of linear polarization was changed indicating different physical origins for these components. Then we measured by fluctuation correlation spectroscopy (FCS) the scattering and fluorescence signal of the particles alone and in a solution of 100 nM EGFP using the spectral camera or measuring the scattering and fluorescence from the particles. We observed occasional fluorescence bursts when in the suspension we added fluorescent proteins. The spectrum of these burst was devoid of the SHG and of the broad emission in contrast to the signal collected from the gold nanoparticles on the glass surface. Instead we found that the spectrum during the burst corresponded closely to the spectrum of the fluorescent protein. An additional control was obtained by measuring the cross-correlation between the reflection from the particles and the fluorescence arising from EGFP both excited at 488 nm. We found a very weak cross-correlation between the AuNPs and the fluorescence confirming that the burst originate from a few particles with a fluorescence signal.Fil: Anzalone, Andrea. University of California at Irvine; Estados UnidosFil: Gabriel, Manuela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Laboratorio de Electrónica Cuántica; Argentina. University of California at Irvine; Estados UnidosFil: Estrada, Laura Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Laboratorio de Electrónica Cuántica; Argentina. University of California at Irvine; Estados UnidosFil: Gratton, Enrico. University of California at Irvine; Estados Unidos. University of New England; Australi

Community Supported Agriculture at Indian Creek Nature Center\u27s Sugar Grove Farm: Sustainable Farming for Iowa

Agriculture is the largest revenue source for the state of Iowa and the state’s two priority crops are corn and soybeans. Farming practices that emphasize monoculture production of these crops can reduce biological diversity and habitat for all-important pollinators, and exacerbate runoff and erosion that sends nutrient-rich soil, herbicides, and pesticides into streams and rivers. The industrial agriculture model is lucrative now, but unsustainable for Iowa over the long run. Sugar Grove Farm, a subset of Indian Creek Nature Center (ICNC), plans to grow a variety of food crops on a large-scale, economically sustainable farm, and support low-income households in Linn County by implementing a subsidized, community supported agriculture (CSA) program. By using the processes of agroecology and restorative agriculture, the nature center will work in conjunction with Iowa’s natural resources to grow quality produce that is affordable for a sector of the community who lacks financial opportunities to purchase quality fresh food. I have worked with numerous community partners, conducted research in agroecology, and conversed with experts in the field. This paper outlines the CSA logistics and plans, providing data and reasoning to the importance of sustainable agriculture and the necessity to educate Iowa’s future farmers to adopt similar techniques. Indian Creek Nature Center’s CSA program will launch in 2018

Should Private Prisons in the U.S. be Abolished

Private prisons were established as a possible solution to alleviate the serious overcrowding issue affecting prisons during the 1980’s. This thesis supports the reasoning behind why private prisons should be abolished as they did not deliver on the claims made in support of their existence but rather, reveals the multitude of negative repercussions when the financial interests of a few large and powerful private corporations override the basic safety and security of our prison system. The studies contained in this thesis attempt to reveal that the data meant to support private prisons is not only inadequate, but often, inaccurately depicted by the same corporations who benefit from their existence. The evidence contained in this thesis offers reasoning that suggest private prisons were not the appropriate solution to the problem and only created a host of other ethical issues, mainly the incentive to incarcerate when a profit is to be made. Suggestions have been made as possible alternatives to private prisons, as well as the need to examine the factors contributing to mass incarceration and how private prisons create obstacles to reform