Wing surface-jet interaction characteristics of an upper-surface blown model with rectangular exhaust nozzles and a radius flap

The wing surface jet interaction characteristics of an upper surface blown transport configuration were investigated in the Langley V/STOL tunnel. Velocity profiles at the inboard engine center line were measured for several chordwise locations, and chordwise pressure distributions on the flap were obtained. The model represented a four engine arrangement having relatively high aspect ratio rectangular spread, exhaust nozzles and a simple trailing edge radius flap

Accounting Capstone Course Design: Using the Internet to Modernize a Graduate Accounting Capstone Course

This second paper describes how the Internet was used to modernize a graduate accounting capstone course to enhance student interest and learning, and is an extension of an earlier paper that examined a similar approach with an undergraduate accounting capstone course. Course content was developed from contemporary issues and cases obtained from the Internet. Benefits, drawbacks, and feedback from students who completed the updated course are presented as a basis for future study. The concepts and techniques presented in this analysis can easily be applied to capstone courses in other disciplines

High Energy Gamma-Ray Emission From Blazars: EGRET Observations

We will present a summary of the observations of blazars by the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO). EGRET has detected high energy gamma-ray emission at energies greater than 100 MeV from more that 50 blazars. These sources show inferred isotropic luminosities as large as $3\times 10^{49}$ ergs s$^{-1}$. One of the most remarkable characteristics of the EGRET observations is that the gamma-ray luminosity often dominates the bolometric power of the blazar. A few of the blazars are seen to exhibit variability on very short time-scales of one day or less. The combination of high luminosities and time variations seen in the gamma-ray data indicate that gamma-rays are an important component of the relativistic jet thought to characterize blazars. Currently most models for blazars involve a beaming scenario. In leptonic models, where electrons are the primary accelerated particles, gamma-ray emission is believed to be due to inverse Compton scattering of low energy photons, although opinions differ as to the source of the soft photons. Hardronic models involve secondary production or photomeson production followed by pair cascades, and predict associated neutrino production.Comment: 16 pages, 7 figures, style files included. Invited review paper in "Observational Evidence for Black Holes in the Universe," 1999, ed. S. K. Chakrabarti (Dordrecht: Kluwer), 215-23

Spatial Bloom Filters: Enabling Privacy in Location-Aware Applications

The wide availability of inexpensive positioning systems made it possible to embed them into smartphones and other personal devices. This marked the beginning of location-aware applications, where users request personalized services based on their geographic position. The location of a user is, however, highly sensitive information: the user's privacy can be preserved if only the minimum amount of information needed to provide the service is disclosed at any time. While some applications, such as navigation systems, are based on the users' movements and therefore require constant tracking, others only require knowledge of the user's position in relation to a set of points or areas of interest. In this paper we focus on the latter kind of services, where location information is essentially used to determine membership in one or more geographic sets. We address this problem using Bloom Filters (BF), a compact data structure for representing sets. In particular, we present an extension of the original Bloom filter idea: the Spatial Bloom Filter (SBF). SBF's are designed to manage spatial and geographical information in a space efficient way, and are well-suited for enabling privacy in location-aware applications. We show this by providing two multi-party protocols for privacy-preserving computation of location information, based on the known homomorphic properties of public key encryption schemes. The protocols keep the user's exact position private, but allow the provider of the service to learn when the user is close to specific points of interest, or inside predefined areas. At the same time, the points and areas of interest remain oblivious to the user

Inferring stabilizing mutations from protein phylogenies : application to influenza hemagglutinin

One selection pressure shaping sequence evolution is the requirement that a protein fold with sufficient stability to perform its biological functions. We present a conceptual framework that explains how this requirement causes the probability that a particular amino acid mutation is fixed during evolution to depend on its effect on protein stability. We mathematically formalize this framework to develop a Bayesian approach for inferring the stability effects of individual mutations from homologous protein sequences of known phylogeny. This approach is able to predict published experimentally measured mutational stability effects (ΔΔG values) with an accuracy that exceeds both a state-of-the-art physicochemical modeling program and the sequence-based consensus approach. As a further test, we use our phylogenetic inference approach to predict stabilizing mutations to influenza hemagglutinin. We introduce these mutations into a temperature-sensitive influenza virus with a defect in its hemagglutinin gene and experimentally demonstrate that some of the mutations allow the virus to grow at higher temperatures. Our work therefore describes a powerful new approach for predicting stabilizing mutations that can be successfully applied even to large, complex proteins such as hemagglutinin. This approach also makes a mathematical link between phylogenetics and experimentally measurable protein properties, potentially paving the way for more accurate analyses of molecular evolution

Bad Consequences

When faced with a decision, if one alternative is likely to lead to bad results, a rational person would presumably hesitate before choosing that course of action. Thus, the bad consequences argument tends to have logical and intuitive appeal. Moreover, it is an easy argument to make. Decisions, especially legal decisions, generally do have consequences, and it will usually be difficult to determine exactly what they will be with any certainty. The future, by definition, is uncertain. And yet, it only takes a modicum of imagination to speculate about what very well might happen. The argument of bad consequences can be a powerful tool in the hands of the advocate because it tends to place the opponent in the uncomfortable position of attempting to refute the speculative state of affairs that presently exists only in the advocate\u27s imagination. Given the appeal of this argument, it is hardly surprising that it has been employed with great frequency by the Supreme Court of the United States from the earliest days and continues to play a significant role in contemporary constitutional interpretation. It has been utilized by the Court in many of its most memorable decisions including: Marbury v. Madison, McCulloch v. Maryland, Lochner v. New York, Youngstown Steel & Tube Co. v. Sawyer, New York Times Co. v. Sullivan, Mapp v. Ohio, Griswold v. Connecticut, Miranda v. Arizona, United States v. Nixon, Bakke v. Regents of the University of California, just to mention a few. Although bad consequences is an easy argument to make and a frequent argument made, it is not always a convincing argument. Nor is it necessarily a bad argument. To a large extent, it depends on the advocate\u27s ability to persuade the reader that bad things are, in fact, likely to occur if a particular course of action is followed. This article will examine several aspects of the bad consequences argument. First, it will briefly consider instances in which the bad consequences argument is employed as a means of bolstering some other form of constitutional argument. Next, it will examine the use of the bad consequences argument as a rhetorical device. Then it will consider the issue of whether there needs to be some showing that bad consequences will actually occur. Next, it will discuss cases in which the bad consequences in question are legal rules or doctrines which the Court itself has some ability to avoid. Finally, it will discuss constitutional boundary disputes in which the bad consequences argument has become something of a structural principle