The impacts for stone curlews of increased traffic on the A11. Model and predictions

Stone curlew nest density in the Breckland region of Eastern England was shown to be negatively related to ‘nearby’ housing density and ‘nearby’ trunk road traffic (based on new traffic data for the period 1988-2006). However, no statistically significant additional relationship with non-trunk A-road traffic could be detected. We recommend using the statistical modelling predictions in the report Table 5 as the best currently available estimates of the potential effect of a 70% increase in A11 average daily (March-August)two-way traffic above the average All traffic levels in 2002-06. The predicted effect of a 70% increase in A11 traffic is for a reduction from current observed nest numbers on suitable arable land of 3.7% with no changes in housing density or 4.9% when combined with the predicted effect of housing options. A reduction of 7.3% is predicted for semi-natural grassland and SSSI habitats. Taking both semi-natural grassland/SSSI and arable habitats together, the observed total average nest numbers for the period 2002-2006 was 221.4, and the prediction following a 70% increase in traffic on the A11 is 210.8, a reduction of 10.6 nests (4.8%)

Study of storm time fluxes of heavy ions

Ion composition data sets from Lockheed instruments on a variety of spacecraft were used in combination with each other and with data from other instruments to address a variety of problems regarding plasma sources, energization and transport within the magnetosphere. The availability of data from several differing orbits has given a highly flexible approach to attacking the continually evolving questions of magnetospheric physics. This approach is very successful and should be continued in the future

A structural and thermal packaging approach for power processing units for 30-cm ion thrusters

Solar Electric Propulsion (SEP) is currently being studied for possible use in a number of near earth and planetary missions. The thruster subsystem for these missions would consist of 30 centimeter ion thrusters with Power Processor Units (PPU) clustered in assemblies of from two to ten units. A preliminary design study of the electronic packaging of the PPU has been completed at Lewis Research Center of NASA. This study evaluates designs meeting the competing requirements of low system weight and overall mission flexibility. These requirements are evaluated regarding structural and thermal design, electrical efficiency, and integration of the electrical circuits into a functional PPU layout

Sensitive Product Treatment in Agricultural Trade Negotiations

The fact that trade, and especially agricultural trade, remains far from free is puzzling, since the superiority of free trade receives overwhelming support among economists (Gawande and Krishna, 2003; Rodrik, 1994). International trade scholars have devoted significant resources to forecasting the impact of trade policy reforms (for a survey of these studies see Congressional Budget Office, 2005), and their findings are relevant inputs for officials negotiating a trade agreement as well as for politicians in charge of ratifying it. The perceived gains and losses attached to different outcomes have been identified as a significant factor shifting the outcome of a trade agreement negotiation (McMillan, 1990). Less well-known are the factors that would impact the result of a negotiation round involving agriculture. While political scientists have devoted significant resources and developed numerous theories to explain the pattern of bargaining outcomes, the number of empirical assessments remains limited. Among the factors to blame for the low number of empirical evaluations is the scarcity of information regarding negotiation strategies and outcomes (Odell, 2002). The lack of research in this area is puzzling, since countries negotiating regionally and multilaterally have many times struggled to satisfactorily conclude negotiations due to a lack of consensus on agriculture. The potential gains that a reduction in agricultural protection worldwide could generate, and the limited knowledge on the ways negotiation outcomes can be affected, are the main motivations for this study. As stated by Hoekman and Anderson (1999) in reference to reaching an agreement on agriculture in the current WTO Doha Round of negotiations, “The potential gains from liberalization are large”, but “Getting there is another matter” (p. 175). This study focuses on U.S. trade negotiations with Western Hemisphere countries, with particular attention to sensitive agricultural products, about which the most heated bargaining occurs. Arguably as a consequence of the lack of progress at the multilateral arena, the U.S. has embarked on bilateral trade negotiations with several countries, but with a particular emphasis with Western Hemisphere partners. Thus, over the last 10 years it has ratified trade agreements with Chile, Peru, Costa Rica, Dominican Republic, El Salvador, Guatemala, Honduras, and Nicaragua (the last six as part of the DR-CAFTA Agreement), and signed but not yet ratified agreements with Colombia and Panama. Following Trefler (1993), a simultaneous equation model is developed to estimate the correlation between the change in market access (ΔMA) as a result of free trade negotiations, and a number of political economy (PA) and negotiation context (NC) variables suggested by the endogenous tariff theory to be associated with the level of protection granted to a sector. The change in market access in the context of this study is represented by changes in import tariffs and tariff-rate-quotas negotiated as part of the preferential trade agreements (PTAs). While we acknowledge the increasing importance of non-tariff barriers (other than TRQs) as a way to afford protection from imports, PTAs usually do not include specific outcomes on NTBs, and therefore gauging the change in NTBs resulting from a PTA is not possible. Negotiation process variables (NP) primarily bargaining strategies, are seen by many scholars as important intervening variables to explain the pattern of market access achieved in bargaining. By focusing on sensitive agricultural products, this study controls for (NP) variables, since negotiations on sensitive agricultural products between the U.S. and its developing Western Hemisphere partners are assumed to have entailed the use of strong bargaining strategies on both sides. Political economy variables subject to be used are economic size, concentration ratios, import penetration ratios and their change, capital/labor ratios, and sectoral to total labor ratios, all argued to be positively related to the level of protection granted to a sector. Among feasible negotiation context variables are relative power of nations, foreign direct investment in the partner’s economy, unemployment rate, and tax structure (dependence on import policies as a source of revenues). The level of imports (IMP) is modeled to be a function of comparative advantage variables (CA) and the change in market access ΔMA. ΔMA = f(PA, NC NP) IMP = f(CA, ΔMA) The findings from the quantitative assessment are to be complemented with findings from selected case studies, thus expanding our understanding of the factors affecting the outcome of the bargaining activity over sensitive agricultural products in the context of preferential trade agreements.trade negotiations, agricultural trade, free trade agreements, political economy, Agricultural and Food Policy, International Relations/Trade, Political Economy, F59, Q17,

Mass study for modular approaches to a solar electric propulsion module

The propulsion module comprises six to eight 30-cm thruster and power processing units, a mercury propellant storage and distribution system, a solar array ranging in power from 18 to 25 kW, and the thermal and structure systems required to support the thrust and power subsystems. Launch and on-orbit configurations are presented for both modular approaches. The propulsion module satisfies the thermal design requirements of a multimission set including: Mercury, Saturn, and Jupiter orbiters, a 1-AU solar observatory, and comet and asteroid rendezvous. A detailed mass breakdown and a mass equation relating the total mass to the number of thrusters and solar array power requirement is given for both approaches

Spectral pitch distance and microtonal melodies

We present an experiment designed to test the effectiveness of spectral pitch distance at modeling the degree of “affinity” or “fit” of pairs of successively played tones or chords (spectral pitch distance is the cosine distance between salience-weighted, Gaussian-smoothed, pitch domain embeddings of spectral pitches—typically the first eight to ten partials of a tone). The results of a previously conducted experiment, which collected ratings of the perceived similarity and fit of root-position major and minor triads, suggest the model works well for pairs of triads in standard 12-tone equal temperament tunings. The new experiment has been designed to test the effectiveness of spectral pitch distance at modeling the affinity of tones in microtonal melodies where the partials of the tones can be variably tempered between being perfectly harmonic and perfectly matched to the underlying microtonal tuning. The use of microtonal tunings helps to disambiguate innate perceptual (psychoacoustical) responses from learned (cultural) responses. Participants are presented with a software synthesizer containing two unlabeled controls: one adjusts the precise tuning of the tones; the other adjusts the extent to which the spectrum is tempered to match the tuning (as set by the first control). A selection of microtonal melodies are played in different tunings, and the participants adjust one, or both, controls until they find a “sweet spot” at which the music sounds most “in-tune” and the notes best “fit” together. The results of these experiments will be presented and discussed

Metrics for pitch collections

Models of the perceived distance between pairs of pitch collections are a core component of broader models of the perception of tonality as a whole. Numerous different distance measures have been proposed, including voice-leading, psychoacoustic, and pitch and interval class distances; but, so far, there has been no attempt to bind these different measures into a single mathematical framework, nor to incorporate the uncertain or probabilistic nature of pitch perception (whereby tones with similar frequencies may, or may not, be heard as having the same pitch). To achieve these aims, we embed pitch collections in novel multi-way expectation arrays, and show how metrics between such arrays can model the perceived dissimilarity of the pitch collections they embed. By modeling the uncertainties of human pitch perception, expectation arrays indicate the expected number of tones, ordered pairs of tones, ordered triples of tones and so forth, that are heard as having any given pitch, dyad of pitches, triad of pitches, and so forth. The pitches can be either absolute or relative (in which case the arrays are invariant with respect to transposition). We provide a number of examples that show how the metrics accord well with musical intuition, and suggest some ways in which this work may be developed

Development of a polysilicon process based on chemical vapor deposition, phase 1

The development of a dichlorosilane-based reductive chemical vapor deposition process for the production of polycrystalline silicon is discussed. Experimental data indicate that the ease of ignition and explosion severity of dichlorosilane (DCS)/air mixtures is substantially attenuated if the DCS is diluted with hydrogen. Redesign of the process development unit to accommodate safety related information is described. Several different sources of trichlorosilane were used to generate a mixture of redistributed chlorosilanes via Dowex ion exchange resin. The unseparated mixtures were then fed to an experimental reactor in which silicon was deposited and the deposited silicon analyzed for electrically active impurities. At least one trichlorosilane source provided material of requisite purity. Silicon grown in the experimental reactor was converted to single crystal material and solar cells fabricated and tested

Subglacial drainage processes at a High Arctic polythermal valley glacier

Peer reviewedPublisher PD