Wind-tunnel investigation of the validity of a sonic-boom-minimization concept

The Langley unitary plan unitary plan wind tunnel was used to determine the validity of a sonic-boom-minimization theory. Five models - two reference and three low-boom constrained - were tested at design Mach numbers of 1.5 and 2.7. Results show that the pressure signatures generated by the low-boom models had significantly lower overpressure levels than those produced by the reference models and that small changes in the Mach number and/or the lift caused relatively small changes in the signature shape and overpressure level. Boundary-layer effects were found in the signature shape and overpressure level. Boundary-layer effects were found to be sizable on the low-boom models, and when viscous corrections were included in the analysis, improved agreement between the predicted and the measured signatures was noted. Since this agreement was better at Mach 1.5 than at Mach 2.7, it was concluded that the minimization method was definitely valid at Mach 1.5 and was probably valid at Mach 2.7, with further work needed to resolve the uncertainty

Current research in sonic-boom minimization

A review is given of several questions as yet unanswered in the area of sonic-boom research. Efforts, both here at Langley and elsewhere, in the area of minimization, human response, design techniques and in developing higher order propagation methods are discussed. In addition, a wind-tunnel test program being conducted to assess the validity of minimization methods based on a forward spike in the F-function is described

A Pilot Study of Halal Goat-Meat Consumption in Atlanta, Georgia

Atlanta is a relatively large market for goat meat. As in most metropolitan areas around the U.S., goat-meat consumption has grown steadily in Atlanta over the past decade (Northwest Cooperative Development Center 2005; Nettles and Bukenya 2004). This growth is attributed to the influx of immigrants from goat-meat-eating countries into the U.S. over the same period (Gipson 1999). The increase in demand for goat meat has made the U.S. a net importer of competitively priced goat meat from Australia and New Zealand into major U.S cities such as Atlanta (USDA-FAS 2006). The fact that goat-meat imports from Australia have steadily increased over the years makes markets such as Atlanta of particular interest to both Georgia goat-meat suppliers and meat-goat producers. The goat-meat market, however, is highly segmented (Nelson et al. 2004; Mclean-Meyinsse 2003). Recognition of the diversity among Atlanta goat-meat consumers raises interest in identifying preferences of particular segments. One such segment is the Muslim consumer. However, very limited information is available to help assess the preferences of Muslim consumers in the Atlanta goat-meat market. This study focuses on the Muslim segment of actual goat-meat consumers in the metro Atlanta area. Contrary to earlier assertions, we hypothesize that Muslims eat goat-meat for cultural reasons and not for religious reasons. Furthermore, we assert that Muslims are not a single homogenous niche group and should not be treated as such in marketing. Thus this study examines goat-meat consumption patterns among Muslims in metropolitan Atlanta. Insights gained in this study benefit meat-goat producers and consumers in Georgia.Food Consumption/Nutrition/Food Safety, Livestock Production/Industries,

Absolute and convective instabilities of an inviscid compressible mixing layer: Theory and applications

This study aims to examine the effect of compressibility on unbounded and parallel shear flow linear instabilities. This analysis is of interest for industrial, geophysical, and astrophysical flows. We focus on the stability of a wavepacket as opposed to previous single-mode stability studies. We consider the notions of absolute and convective instabilities first used to describe plasma instabilities. The compressible-flow modal theory predicts instability whatever the Mach number. Spatial and temporal growth rates and Reynolds stresses nevertheless become strongly reduced at high Mach numbers. The evolution of disturbances is driven by Kelvin -Helmholtz instability that weakens in supersonic flows. We wish to examine the occurrence of absolute instability, necessary for the appearance of turbulent motions in an inviscid and compressible two-dimensional mixing layer at an arbitrary Mach number subject to a three-dimensional disturbance. The mixing layer is defined by a parametric family of mean-velocity and temperature profiles. The eigenvalue problem is solved with the help of a spectral method. We ascertain the effects of the distribution of temperature and velocity in the mixing layer on the transition between convective and absolute instabilities. It appears that, in most cases, absolute instability is always possible at high Mach numbers provided that the ratio of slow-stream temperature over fast-stream temperature may be less than a critical maximal value but the temporal growth rate present in the absolutely unstable zone remains small and tends to zero at high Mach numbers. The transition toward a supersonic turbulent regime is therefore unlikely to be possible in the linear theory. Absolute instability can be also present among low-Mach-number coflowing mixing layers provided that this same temperature ratio may be small, but nevertheless, higher than a critical minimal value. Temperature distribution within the mixing layer also has an effect on the growth rate, this diminishes when the slow stream is heated. These results are applied to the dynamics of mixing layers in the interstellar medium and to the dynamics of the heliopause, frontier between the interstellar medium, and the solar wind. (C) 2009 American Institute of Physics

Polymer Dissolution Model: An Energy Adaptation Of The Critical Ionization Theory

The current scale of features size in the microelectronics industry has reached the point where molecular level interactions affect process fidelity and produce excursions from the continuum world like line edge roughness (LER). Here we present a 3D molecular level model based on the adaptation of the critical ionization (CI) theory using a fundamental interaction energy approach. The model asserts that it is the favorable interaction between the ionized part of the polymer and the developer solution which renders the polymer soluble. Dynamic Monte Carlo methods were used in the current model to study the polymer dissolution phenomenon. The surface ionization was captured by employing an electric double layer at the interface, and polymer motion was simulated using the Metropolis algorithm. The approximated interaction parameters, for different species in the system, were obtained experimentally and used to calibrate the simulated dissolution rate response to polymer molecular weight and developer concentration. The predicted response is in good agreement with experimental dissolution rate data. The simulation results support the premise of the CI theory and provide an insight into the CI model from a new prospective. This model may provide a means to study the contribution of development to LER and other related defects based on molecular level interactions between distinct components in the polymer and the developer.Chemical Engineerin

Polemic in the International Court of Justice

Jurisprudence, used as a technical term, has two meanings of equal currency, referring both to a philosophy of law and a science which treats of the principles of positive law and legal relations. These meanings are vastly different in import. Philosophy suggests speculation and ideology, while science suggests fact and functionalism. Jurisprudence, like any discipline of observation and conclusion, can be a very useful tool in the legal analysis of one\u27s own work and the work of others. The science, with its clear sight and objective standards, is obviously more dependable than the polemics of philosophy, and therefore the sole approach to be used in situations that demand objectivity. If any area of jurisprudence demands this objectivity, it is the area of judicial decision. It is the premise of this Comment that much of what is written about legal judgments, and often the judgments themselves, contain so much polemic that they sometimes produce results contrary to a primary function of legal systems, the settlement of disputes. This is an especially critical problem in the international sphere, where the tendency to mix fact and polemic often detracts from the legal justifications of a particular dispute\u27s resolution

The New Collection Development: Planning and Assessment to Promote Innovation

Library collections are in the midst of a radical transformation. Rapidly evolving technology, innovations in distributing and accessing content, new models of pricing, repurposing of library spaces, and shrinking collections budgets create a new environment for collection development. This new environment requires that librarians participate in a variety of new collection development activities beyond just selecting content. In the emerging library collection development landscape librarians must engage with the disciplinary content of collections as well as a range of other areas. New areas of responsibility might include: information technology, including issues of personal data curation; copyright, open access, and scholarly communication; new modes for delivery of content; budgeting, development, fundraising, and stewardship of resources; collections issues regarding space, preservation, curation, and storage of collections in all formats; and integrating collections issues into instruction, reference, readers’ advisory, programming and other engagement with the library’s users, and funders and other stakeholders. These and other activities continue to take an increasing amount of time and effort on the part of collection development librarians. In many cases, however, librarians and library administrators are not adequately prepared to incorporate these activities into their portfolios. The audience will engage in a dialog about incorporating new and emerging collection development activities into training programs, strategic plans, work plans, and assessment activities. Attendees will leave with tools for incorporating innovation into their institutions’ operations

Torts—Products Liability Cases—Privity No Longer Required

Goldberg v. Kollsman Instrument Corp., 12 N.Y.2d 432, 240 N.Y.S.2d 592, 191 N.E.2d 81 (1963)