An updated cool dwarf catalog for the transiting exoplanet survey satellite using Gaia DR2

An undergrad mentee of mine presented results at the meeting in a poster. I am a co-author of the presentation. The abstract is available on ADS: https://ui.adsabs.harvard.edu/abs/2019AAS...23314001C/abstractWe present an updated catalog of cool dwarf stars for the recently launched Transiting Exoplanet Survey Satellite (TESS) for the purpose of selecting targets for two-minute cadence observations. At launch, TESS was provided a similar catalog of cool dwarfs whose stellar parameters were approximated using proper motions and — where they existed — archival parallax measurements. Most targets therefore have significant uncertainties. Now, with the highly anticipated Gaia DR2 parallax measurements released in April 2018, we updated stellar parameters where we are able to determine a cross-match with confidence, as well as determined new targets from a cross-match between Gaia and 2MASS. We anticipate delivery to TESS by the end of 2018, at which point it will have completed about one fourth of its mission. With the updated catalog, we hope that TESS will discover Earth-sized and sub-Earth-sized exoplanets around late K and M-dwarf type stars with a higher planet yield. This project was supported in part by the NSF REU grant AST-1757321 and by the Nantucket Maria Mitchell Association.Published versio

Financial Exchange Rates and International Currency Exposures

Our goal in this project is to gain a better empirical understanding of the international financial implications of currency movements. To this end, we construct a database of international currency exposures for a large panel of countries over 1990-2004. We show that trade-weighted exchange rate indices are insufficient to understand the financial impact of currency movements. Further, we demonstrate that many developing countries hold short foreign-currency positions, leaving them open to negative valuation effects when the domestic currency depreciates. However, we also show that many of these countries have substantially reduced their foreign currency exposure over the last decade. Last, we show that our currency measure has high explanatory power for the valuation term in net foreign asset dynamics: exchange rate valuation shocks are sizable, not quickly reversed and may entail substantial wealth shocks.

System Energy Assessment (SEA), Defining a Standard Measure of EROI for Energy Businesses as Whole Systems

A more objective method for measuring the energy needs of businesses, System Energy Assessment (SEA), identifies the natural boundaries of businesses as self-managing net-energy systems, of controlled and self-managing parts. The method is demonstrated using a model Wind Farm case study, and applied to defining a true physical measure of its energy productivity for society (EROI-S), the global ratio of energy produced to energy cost. The traceable needs of business technology are combined with assignable energy needs for all other operating services. That serves to correct a large natural gap in energy use information. Current methods count traceable energy receipts for technology use. Self-managing services employed by businesses outsource their own energy needs to operate, and leave no records to trace. Those uncounted energy demands are often 80% of the total embodied energy of business end products. The scale of this "dark energy" was discovered from differing global accounts, and corrected so the average energy cost per dollar for businesses would equal the world average energy use per dollar of GDP. Presently the energy needs of paid services that outsource their own energy needs are counted for lack of information to be "0". Our default assumption is to treat them as "average". The result is to assign total energy use and impacts to the demand for energy services, for a "Scope 4" GHG assessment level. Counting only the energy uses of technology understates the energy needs of business services, as if services were more energy efficient than technology. The result confirms a similar finding by Hall et. al. in 1981 [9]. We use exhaustive search for what a business needs to operate as a whole, locating a natural physical boundary for its working parts, to define businesses as physical rather than statistical subjects of science. :measurement, natural systemsComment: 33 pages, 15 figures, accepted as part of pending special issue on EROI organized by Charlie Hall for Sustainability (MDPI

Financial exchange rates and international currency exposures

Our goal in this project is to gain a better empirical understanding of the international financial implications of currency movements. To this end, we construct a database of international currency exposures for a large panel of countries over 1990-2004. We show that trade-weighted exchange rate indices are insufficient to understand the financial impact of currency movements. We show that our currency measure has high explanatory power for the valuation term in net foreign asset dynamics: exchange rate valuation shocks are sizable, not quickly reversed and may entail substantial wealth redistributions. Further, we demonstrate that many developing countries hold short foreign-currency positions, leaving them open to negative valuation effects when the domestic currency depreciates. However, we also show that many of these countries have substantially reduced their foreign currency exposure over the last decade. --Financial integration,capital flows,external assets and liabilities

Financial Exchange Rates and International Currency Exposures

Our goal in this project is to gain a better empirical understanding of the international financial implications of currency movements. To this end, we construct a database of international currency exposures for a large panel of countries over 1990-2004. We show that trade-weighted exchange rate indices are insufficient to understand the financial impact of currency movements. Further, we demonstrate that many developing countries hold short foreign-currency positions, leaving them open to negative valuation effects when the domestic currency depreciates. However, we also show that many of these countries have substantially reduced their foreign currency exposure over the last decade. Last, we show that our currency measure has high explanatory power for the valuation term in net foreign asset dynamics: exchange rate valuation shocks are sizable, not quickly reversed and may entail substantial wealth shocks.Financial integration, capital flows, external assets and liabilities

The Present Status of Caries Control Measures

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66996/2/10.1177_00220345480270031701.pd

Russell W. Bunting President of the IADR, 1932—33

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66925/2/10.1177_00220345630420012001.pd

The Long or Short of it: Determinants of Foreign Currency Exposure in External Balance Sheets

Recently, there have been numerous advances in modelling optimal international portfolio allocations in macroeconomic models. A major focus of this literature has been on the role of currency movements in determining portfolio returns that may hedge various macroeconomic shocks. However, there is little empirical evidence on the foreign currency exposures that are embedded in international balance sheets. Using a new database, we provide stylized facts concerning the cross-country and time-series variation in aggregate foreign currency exposure and its various subcomponents. In panel estimation, we find that richer, more open economies take longer foreign-currency positions. In addition, we find that an increase in the propensity for a currency to depreciate during bad times is associated with a longer position in foreign currencies, providing a hedge against domestic output fluctuations. We view these new stylized facts as informative in their own right and also potentially useful to the burgeoning theoretical literature on the macroeconomics of international portfolios.

Evaluation of the Spherical Flange Concept for a Rocket Engine

Due to the inherent tolerance variability of hardware, flange misalignments occur during installation of mating components for a liquid propellant rocket engine. Flange misalignments include axial, lateral, and angular offsets. If these misalignments are high, they can impart significant loads into the two mating components. These significant loads can then be a driver in the design of the propellant ducts. Such was the case for the Rocketdyne RS-83 engine design for the Space Launch Initiative Program. To address this flange misalignment issue, Marshall Space Flight Center joined with Rocketdyne to develop and test a spherical flange system that allows for misalignment, yet reduces loads imparted, and at the same time provides sufficient sealing against leakage. The flange design was tested to evaluate and compare performance parameters such as misalignment and leakage. The environmental conditions ranged from -100 to 400 degrees Fahrenheit (F) with 1000 to 4000 pounds per square inch gage (psig) pressure. The desirable design features will be extracted and synthesized into a new flange design concept. This paper will address the spherical flange design and the test results