Development of a propane burning annular combustor for use in a miniature gas turbine engine

Propane annular combustor for use in miniature gas turbine engine for wind tunnel

Development of a trash handling subsystem for a manned spacecraft

A prototype laboratory system to shred and transport trash material within a spacecraft was designed and demonstrated. In addition to handling the normal trash materials, the system demonstrated the ability to handle or reject (if it is too tough) glass, metal and ceramics without damaging the system. The system is not dependent on liquids for the shredding and transportation and can transport slurried, damp or dry material. The resulting system offers a greater system flexibility with operational reliability

The Dilemma of Direct Democracy

The dilemma of direct democracy is that voters may not always be able to make welfare- improving decisions. Lupia’s seminal work has led us to believe that voters can substitute voting cues for substantive policy knowledge. Lupia, however, emphasized that cues were valuable under certain conditions and not others. In what follows, we present three main findings regarding voters and what they know about California’s Proposition 7. First, much like Lupia reported, we show voters who are able to recall endorsements for or against a ballot measure vote similarly to people who recall certain basic facts about the initiative. We show, second, that voters whose stated policy preferences would otherwise suggest they would favor the “no” position cast their ballots with far less error than do people who favor the “yes” position. One thing this suggests is that many voters may employ a “defensive no” strategy when faced with complex policy choices on the ballot. Our third result is a bit surprising: we find that better- informed voters, whether this information is derived from factual knowledge of the initiative or from knowledge of well-publicized voting cues, are no more likely to make reasoned decisions than those who are, by our measure, uninformed. This suggests that existing theories of voter choice, especially in direct democracy, may be inadequate. We conclude with some preliminary policy recommendations that could help improve the information environment for initiatives and referenda by providing key information on the ballot

Determinants of Success in High School Economics: Lessons from the Field

Recently, the Hawaii Council on Economic Education conducted a survey of high school seniors to gauge their understanding of basic economic concepts. Based on these results, we conduct a series of case studies, consisting of interviews with principals and economics teachers at eight Hawaii public high schools. We summarize the qualitative and quantitative results of these interviews. We then use these and other data to estimate the effects of school, demographic, and other characteristics on average student achievement on the survey. We find that the improvement in student test scores as a result of a one semester economics course is modest, but that the single greatest determinant of achievement is overall school quality. Based on these and other findings, we present recommendations for policy and further research.

Economic Impacts of E. Coqui frogs in Hawaii

Eleutherodactylus coqui, a small frog native to Puerto Rico, was introduced to Hawaii in the late 1980s, presumably as a hitchhiker on plant material from the Caribbean or Florida (Kraus et al. 1999). The severity of the frogs' songs on the island of Hawaii has lead to a hypothesis touted both in the scientific community and in the popular media that the presence of the frog on or near a property results in a decline in that property's value. The objective of this study is to explicitly test the extent to which this hypothesis is true, and if it is, what the level of localized damage incurred on a property's value is. The invasion began on either Hawaii or Maui, and has now expanded to Oahu and Kauai. Spread has occurred through the movement of nursery plants and through intentional introduction of the frogs to previously uninfested areas. The coqui frogs have attained some of the highest densities ever observed for terrestrial amphibian populations (up to 133,000 per ha on Hawaii). These extremely dense populations have lead to both economic and ecological concerns, especially on the island of Hawaii. The loud mating song of the male frogs is the most widely cited complaint in Hawaii. The frog's song has been measured to range in the 80-100 decibel level (Beard and Pitt 2005). Given that 45 decibels may be enough to prevent the average person from sleeping , the song of the coqui is considered a form of noise pollution in Hawaii. In this study we focus only on the direct damage costs of the coqui's loud mating songs through a hedonic pricing model. Because this only one component of the economic costs of noise pollution, it should be considered a lower bound estimate of the true cost of their noise and their presence. Since this lower bound is generated through measurable losses in property value, its use in invasive species policy should be welcomingly straightforward compared to survey methods or other efforts to quantify damages from ecosystem change. We find that coqui frogs do impose localized damages to real estate values, but by 800 meters distance from a complaint this damage is declining relative to the effect at 500m. The per-transaction reduction in value when frog complaints have been lodged within 500m appears to be about 0.16%, holding constant district, acreage, financial conditions, zoning, and neighborhood characteristics. This is just over 1/3 of the impact that an increase of 1% in mortgage rates is estimated to have on price.Land Economics/Use,

Dynamics of the BCS-BEC crossover in a degenerate Fermi gas

We study the short-time dynamics of a degenerate Fermi gas positioned near a Feshbach resonance following an abrupt jump in the atomic interaction resulting from a change of external magnetic field. We investigate the dynamics of the condensate order parameter and pair wavefunction for a range of field strengths. When the abrupt jump is sufficient to span the BCS to BEC crossover, we show that the rigidity of the momentum distribution precludes any atom-molecule oscillations in the entrance channel dominated resonances observed in the 40K and 6Li. Focusing on material parameters tailored to the 40K Feshbach resonance system at 202.1 gauss, we comment on the integrity of the fast sweet projection technique as a vehicle to explore the condensed phase in the crossover regionComment: 5 pages, 4 figure

Environmental Policy Issues for Sustainable Economic Development in China

A central pillar of the sustainability movement is the call to include environmental accounting in standard measures of economic performance. This increased transparency would, in principle, mitigate the temptation of economic managers and policy makers to increase growth in material consumption at the expense of the environment. Moreover, as Repetto (1989) and others have argued, deducting depreciation of produced capital from NNP but not deducting depreciation of natural capital is inconsistent and debases NNP as a possible indicator of welfare. Based on the evidence available, it appears that while GNNP is substantially less than NNP, these adjustments do not adversely compromise existing estimates of economic growth for China.Environmental Economics and Policy,

Association of molecules using a resonantly modulated magnetic field

We study the process of associating molecules from atomic gases using a magnetic field modulation that is resonant with the molecular binding energy. We show that maximal conversion is obtained by optimising the amplitude and frequency of the modulation for the particular temperature and density of the gas. For small modulation amplitudes, resonant coupling of an unbound atom pair to a molecule occurs at a modulation frequency corresponding to the sum of the molecular binding energy and the relative kinetic energy of the atom pair. An atom pair with an off-resonant energy has a probability of association which oscillates with a frequency and time-varying amplitude which are primarily dependent on its detuning. Increasing the amplitude of the modulation tends to result in less energetic atom pairs being resonantly coupled to the molecular state, and also alters the dynamics of the transfer from continuum states with off-resonant energies. This leads to maxima and minima in the total conversion from the gas as a function of the modulation amplitude. Increasing the temperature of the gas leads to an increase in the modulation frequency providing the best fit to the thermal distribution, and weakens the resonant frequency dependence of the conversion. Mean-field effects can alter the optimal modulation frequency and lead to the excitation of higher modes. Our simulations predict that resonant association can be effective for binding energies of order $h \times 1$ MHz.Comment: 8 pages latex, figures revised, references updated and typos correcte