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Volatile Particulate Matter (vPM) emissions are challenging to measure and quantify, since they are not present in the condensed form at the engine exit plane and they evolve to first form in the aircraft plume and then continue to grow and change as they mix and dilute in the ambient atmosphere. To better understand the issues associated with the initial formation and growth of vPM, a modeling study has been undertaken to examine several key parameters that affect the formation and properties of the vPM that is created in the initial cooling and dilution of the aircraft exhaust. A modeling tool (Aerosol Dynamic Simulation Code, ADSC) that was developed and enhanced over a series of past research projects supported by NASA, DoD's SERDP/ESTCP, and FAA was used to perform a parametric analysis of vPM. The parameters of fuel sulfur content (FSC), emitted condensable hydrocarbon (HC) concentrations, and the species profile of the HCs were used to construct a computational matrix that framed a wide range of expected parameter values. This computational matrix was executed for two representative commercial aircraft engines at ground idle and results were obtained for distances of 250 m and 1000 m downstream. From prior results, the most significant vPM emissions occur at the lowest power settings, so an engine power condition of 7% rated thrust was used. A primary goal of the parametric study is to develop an updated vPM modeling methodology and also to help interpret data collected in experimental campaigns. The parameterization proposed here allows the vPM emission composition and particle numbers to be estimated in greater detail than current methods. The aim is to provide additional understanding on how the vPM properties vary with fuel and engine parameters to increase the utility of vPM predictions. Implications: Volatile Particulate Matter (vPM) is an important contribution to the total PM emitted by aviation engines. While vPM is not currently a part of engine emissions certification regulations, vPM is used in aviation environmental impact assessments and for air quality modeling in and around airports. Current methods in use, such as FOA, were developed before many recent advances in experimental data acquisition and in understanding of vPM processes. The parameterization proposed here allows the vPM emission composition and particle numbers to be estimated in greater detail than current methods. These estimates can be used to develop inventories and provide a better estimate of total emission for most aviation engines. Its use in international regulatory tools can inform possible future regulatory actions regarding vPM. [ABSTRACT FROM AUTHOR]

Debates about Islamophobia have been blighted by the question of whether the prejudice can be defined as a form of racism or as hostility to religion (or a combination of the two). This paper sheds light on this debate by presenting the findings of a new nationally representative survey, focused on the UK, that contrasts perceptions of Muslims not only with perceptions of other ethnic and religious minorities but also with perceptions of Islam as a religious tradition. We find that prejudice against Muslims is higher than for any other group examined other than Travellers. We also find contrasting demographic drivers of prejudice towards Muslims and towards Islam. Across most prejudice measures we analyse, intolerant views are generally significantly associated with being male, voting Conservative and being older, although not with Anglican identity. We find, however, that class effects vary depending on the question's focus. Anti‐immigration sentiment – including support for a 'Muslim ban' – is significantly correlated with being working‐class. However, prejudice towards Islam as a body of teachings (tested using a question measuring perceptions of religious literalism) is significantly correlated with being middle‐class, as is negative sentiment towards Travellers. Using these findings, the paper makes an argument for supplementing recent scholarship on the associations between racism and Islamophobia with analyses focusing on misperceptions of belief. [ABSTRACT FROM AUTHOR]

Within the last 20 years sociological research on science and religion has provided new insights that challenge myths regarding conflicts between science and religion. Gaps in pre-existing work have been identified resulting in major shifts in the field. In particular, research has employed more mixed methods, widened its scope to become more international, and expanded to include nonreligion. Building upon these developments and critiques, this chiefly conceptual article explores a way to move forward by combining three fields of research in a novel way: the sociology of religion, the sociology of nonreligion, and the Public Understanding of Science (PUS). These subfields all touch on relevant and interrelated topics. Sociology of religion contributes to parceling out aspects of belief, identity, and practice; focuses on lived experience along with positionality, normative commitments, and culture. The sociology of nonreligion draws more detailed attention to the association between science and secularism. Finally, including research on PUS provides resources for understanding trust in, and engagement with science dialogically, as well as lessons for effective public engagement. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.polgeo.2005.12.009 Byline: Stephen H. Jones (a), David B. Clarke (b) Abstract: Against the background of the broad intellectual response to the events of 9/11, the paper examines the complicity of the media in the West's so-called War on Terror. Rejecting erroneous conceptions of a conspiratorial state control of the media (and consequent distortion of the picture of a given reality), the paper focuses primarily on the form of the media: its role in distorting the nature of reality itself. By elucidating problems with the kind of media analysis that portrays the media as a propaganda machine, the significance of the mediasphere itself is highlighted. The paper considers the media's role in promulgating the myth of antagonistic collective identities ('Us'vs. 'Them'); in promoting a desire that subjugates the individual to the social formations that feed off it; in sustaining a range of fundamentalisms; and in characterizing terrorism as Evil incarnate. The paper thus offers a sympathetic reassessment of Baudrillard's consistent attempt to engage with the geopolitics of the real, measured against a contrasting range of responses from Badiou, Latour, A1/2iA3/4ek, and others. Author Affiliation: (a) Sociology Department, Goldsmiths College, University of London, New Cross, London SE14 6NW, UK (b) Department of Geography, University of Wales Swansea, Singleton Park, Swansea SA2 8PP, UK

A fast convolution-based computational approach is employed to integrate numerical solid-state device simulation with nonlinear millimeter-wave circuit simulation. Unlike previous combined harmonic-balance/device approaches, the high-frequency circuit/physical device response is allowed to evolve in time to its natural steady-state mode of operation, permitting insight into harmonic and parametric energy exchange, stability, load pulling, and frequency tuning effects. To demonstrate this computationally efficient approach, a second-harmonic 150-GHz transferred electron oscillator is simulated using both conventional Gunn and novel stable-depletion-layer InP devices. The integrated device/circuit simulations in the time domain enable us to investigate the formation and buildup of the oscillation modes in detail. Index Terms - Global modeling, millimeter-wave oscillators.

A second-harmonic InP transferred electron device (TED) for the 63-170 GHz frequency band is studied. The device operates in the second-harmonic mode while drift-diffusion harmonic-balance analysis and high frequency structure simulator are used for analysis. Results show that the TED can produce moderate output power within the 63-170 GHz band while a proper cavity design allows the device to operate in the 60 to 200 GHz band. A mechanically tuned cavity is also developed that continuously tunes between 99 and 147.5 GHz without frequency jumps and produces 30-40 mW of power over the 120 to 147.5 GHz band.

The heterostructure barrier varactor (HBV) diode may be useful in frequency multiplier applications at millimeter and submillimeter wave frequencies. Performance limiting issues for planar HBV's are self-heating and parastitic series resistance. A model shows the effects of device temperature and resistive loss, and a new batch planar four-barrier GaAs/A1(sub0.7)GaAs HBV diodes has undergone tripler testing, producing state-of-the art results.

A nonlinear circuit analysis was conducted to determine a set of analytical design equations for the optimal performance of 50-600 GHz Schottky diode varactor frequency doublers. These equations describe the relationship between voltage, current and power derived from an equivalent varactor circuit model. They allow the calculation of both optimal diode embedding impedances and diode parameters for optimal doubler performance. They thus enable multiplier co-design from both a device and circuit standpoint in a simple, efficient and accurate manner.