869 research outputs found
Counterinsurgency in the 21st century the foundation and implications of the new U.S. doctrine
In December 2006, the U.S. Army published its new counterinsurgency (COIN) Field Manual (FM 3-24). FM 3-24 is the much-anticipated capstone doctrinal COIN guide for the U.S. Army and Marine Corps. Its intent is "to fill a doctrinal gap" for fighting COIN by delivering "a manual that provides principles and guidelines for counterinsurgency operations." The importance of developing a coherent, interdisciplinary approach that helps to fill the "doctrina" and capability gaps facing the U.S. military in the asymmetrical warfare spectrum, including COIN, cannot be overstated. In light of this, how well do the new guidelines in FM 3-24 for conducting a COIN campaign align with historical and social science lessons on counterinsurgency? FM 3-24 outlines U.S. COIN doctrine in the form of strategies called Logical Lines of Operation (LLOs). With this in mind, are there cases in the Middle East where FM 3-24's LLOs have been applied and produced their intended effects? If they were not used and the state power's desired "endstate" was achieved, what strategies were used to achieve the COIN campaign objectives? This thesis assesses the extent to which the field manual aligns with insights and practices from historical COIN campaigns in the Middle East as well as the new doctrine's ability to supply the United States with a COIN strategy that incorporates insights and conclusions from academia. Our findings indicate that FM 3-24 is a necessary step in developing an effective and coherent U.S. approach to COIN. However, it fails to incorporate some more contemporary social movement theory explanations into its strategies. For example, it fails to recognize the relative importance political inclusion in counterinsurgency strategies versus other variables, such as security, as a primary means of success in counterinsurgency campaigns.http://archive.org/details/counterinsurgenc109453099US Army (USA) authorsApproved for public release; distribution is unlimited.Approved for public release; distribution is unlimited
The Radio to Gamma Ray Connection of EGRET Blazars: Correlation, Regression and Monte Carlo Analysis
A comprehensive statistical analysis of the broadband properties of EGRET
blazars is presented. This analysis includes sources identified as blazars in
the Sowards-Emmerd publications. Using this sample of 122 sources, we find that
there is a relationship as well as a
correlation between and , and a correlation between
radio luminosity and . Through the use of Monte Carlo simulations,
we can replicate the observed luminosity relationship if a synchrotron
self-Compton model is assumed. However, this relationship can not be replicated
if an external Compton scattering model is assumed. These differences are
primarily due to beaming effects.
In addition it has been determined that the intrinsic radio luminosity of the
parent sample falls in the range
and that the bulk Lorentz factors of the source are in the range , in a agreement with VLBI observations.
Finally, we discuss implications for GLAST, successfully launched in June
2008
A preliminary analysis of the data from experiment 77-13 and final report on glass fining experiments in zero gravity
Thermal fining, thermal migration of bubbles under reduced gravity conditions, and data to verify current theoretical models of bubble location and temperatures as a function of time are discussed. A sample, sodium borate glass, was tested during 5 to 6 minutes of zero gravity during rocket flight. The test cell contained a heater strip; thermocouples were in the sample. At present quantitative data are insufficient to confirm results of theoretical calculations
Framing the Social Security Earnings Test
In the U.S. Social Security system, the decision of when to claim Social Security benefits is legally independent of when the individual chooses to separate from the workforce. But if an individual claims benefits prior to his âfull retirement ageâ (FRA) while continuing to have labor earnings above a relatively low threshold, his benefits are reduced via the Social Security Earnings Test. The individual is compensated for this benefit reduction in the form of higher benefit payments payable from the FRA for the remainder of the beneficiaryâs lifetime. To the extent that the relevant actuarial adjustment is actuarially fair, the Earnings Test simply represents a re-timing of benefit payments. Nevertheless, many people view the benefit reduction as a tax on earned income after claiming benefits. We posit that whether the Earnings Test influences work and benefit claiming patterns will depend on whether people are aware of the benefit enhancements paid in return for continued work. Using an experimental module of the RAND American Life Panel, we explore how people perceive the Social Security Earnings Test and examine alternative ways to frame the tradeoff between reduced benefits in the short run and higher benefits paid later and for life. Our overall finding is that knowledge of the Earnings Test is uneven, with better educated, higher earning, older individuals showing somewhat greater knowledge than others. The frames we have tested produce only minor effects on individual choices of earnings or claiming ages, and the effects are difficult to reconcile with economic theory
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 ergs s. 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
A Survey for Transient Astronomical Radio Emission at 611 MHz
We have constructed and operated the Survey for Transient Astronomical Radio
Emission (STARE) to detect transient astronomical radio emission at 611 MHz
originating from the sky over the northeastern United States. The system is
sensitive to transient events on timescales of 0.125 s to a few minutes, with a
typical zenith flux density detection threshold of approximately 27 kJy. During
18 months of around-the-clock observing with three geographically separated
instruments, we detected a total of 4,318,486 radio bursts. 99.9% of these
events were rejected as locally generated interference, determined by requiring
the simultaneous observation of an event at all three sites for it to be
identified as having an astronomical origin. The remaining 3,898 events have
been found to be associated with 99 solar radio bursts. These results
demonstrate the remarkably effective RFI rejection achieved by a coincidence
technique using precision timing (such as GPS clocks) at geographically
separated sites. The non-detection of extra-solar bursting or flaring radio
sources has improved the flux density sensitivity and timescale sensitivity
limits set by several similar experiments in the 1970s. We discuss the
consequences of these limits for the immediate solar neighborhood and the
discovery of previously unknown classes of sources. We also discuss other
possible uses for the large collection of 611 MHz monitoring data assembled by
STARE.Comment: 24 pages, 6 figures; to appear in PAS
Design Rules for Self-Assembly of 2D Nanocrystal/Metal-Organic Framework Superstructures.
We demonstrate the guiding principles behind simple two dimensional self-assembly of MOF nanoparticles (NPs) and oleic acid capped iron oxide (Fe3 O4 ) NCs into a uniform two-dimensional bi-layered superstructure. This self-assembly process can be controlled by the energy of ligand-ligand interactions between surface ligands on Fe3 O4 NCs and Zr6 O4 (OH)4 (fumarate)6 MOF NPs. Scanning transmission electron microscopy (TEM)/energy-dispersive X-ray spectroscopy and TEM tomography confirm the hierarchical co-assembly of Fe3 O4 NCs with MOF NPs as ligand energies are manipulated to promote facile diffusion of the smaller NCs. First-principles calculations and event-driven molecular dynamics simulations indicate that the observed patterns are dictated by combination of ligand-surface and ligand-ligand interactions. This study opens a new avenue for design and self-assembly of MOFs and NCs into high surface area assemblies, mimicking the structure of supported catalyst architectures, and provides a thorough fundamental understanding of the self-assembly process, which could be a guide for designing functional materials with desired structure
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