5,769 research outputs found

    Creating An Information Technology Security Program for Educators

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    Information Technology (IT) Security education has become a critical component to college curriculum within the past few years. Along with developing security courses and degrees, there is a need to train college educators and disseminate the security curriculum and best-practices to other colleges. St. Petersburg College implemented a project entitled Information Technology Security and Education for Educators (ITSCEE) designed to address Priority III of the “National Strategy to Secure Cyberspace”, establishment of a “national cyberspace training program.” The project was designed to produce three nationally relevant IT Security degree and certificate programs at the associate, advanced technical certificate, and baccalaureate levels. Also, the project was designed to provide training and an opportunity for the Florida Community College Faculty to obtain certification in the IT Security arena to assist their institutions in deploying relevant IT Security degree programs. This paper will describe the evolution of this project, the success in meeting goals, lessons learned and techniques and best practices other colleges may use to enhance their programs

    CMOS compatible metamaterial absorbers for hyperspectral medium wave infrared imaging and sensing applications

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    We experimentally demonstrate a CMOS compatible medium wave infrared metal-insulator-metal (MIM) metamaterial absorber structure where for a single dielectric spacer thickness at least 93% absorption is attained for 10 separate bands centred at 3.08, 3.30, 3.53, 3.78, 4.14, 4.40, 4.72, 4.94, 5.33, 5.60 μm. Previous hyperspectral MIM metamaterial absorber designs required that the thickness of the dielectric spacer layer be adjusted in order to attain selective unity absorption across the band of interest thereby increasing complexity and cost. We show that the absorption characteristics of the hyperspectral metamaterial structures are polarization insensitive and invariant for oblique incident angles up to 25° making them suitable for practical implementation in an imaging system. Finally, we also reveal that under TM illumination and at certain oblique incident angles there is an extremely narrowband Fano resonance (Q < 50) between the MIM absorber mode and the surface plasmon polariton mode that could have applications in hazardous/toxic gas identification and biosensing

    The Stellar Population of Stripped Cluster Spiral NGC 4522: A Local Analog to K+A Galaxies?

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    We present observations of the stripped Virgo Cluster spiral NGC 4522, a clear, nearby example of a galaxy currently undergoing ISM-ICM stripping. Utilizing SparsePak integral field spectroscopy on the WIYN 3.5m telescope and GALEX UV photometry, we present an analysis of the outer disk (r > 3 kpc) stellar population of this galaxy, beyond the HI and Halpha truncation radius. We find that the star formation in the gas-stripped outer disk ceased very recently, ~100 Myr ago, in agreement with previous claims that this galaxy is currently being stripped. At the time of this stripping, data and models suggest that the galaxy experienced a modest starburst. The stripping is occurring in a region of the cluster well outside the cluster core, likely because this galaxy is experiencing extreme conditions from a dynamic ICM due to an ongoing sub-cluster merger. The outer disk has a spectrum of a K+A galaxy, traditionally observed in high-redshift cluster galaxies. In the case of NGC 4522, a K+A spectrum is formed by simple stripping of the interstellar gas by the hot intracluster medium. These data show K+A spectra can be created by cluster processes and that these processes likely extend beyond the cluster core.Comment: 5 pages, 3 figures, accepted for publication in ApJ Letter

    Density Matrix Perturbation Theory

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    An expansion method for perturbation of the zero temperature grand canonical density matrix is introduced. The method achieves quadratically convergent recursions that yield the response of the zero temperature density matrix upon variation of the Hamiltonian. The technique allows treatment of embedded quantum subsystems with a computational cost scaling linearly with the size of the perturbed region, O(N_pert.), and as O(1) with the total system size. It also allows direct computation of the density matrix response functions to any order with linear scaling effort. Energy expressions to 4th order based on only first and second order density matrix response are given.Comment: 4 pages, 2 figure

    Ripping Apart at the Seams: The Network of Stripped Gas Surrounding M86

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    We present a new study of the Virgo Cluster galaxies M86, M84, NGC 4338, and NGC 4438 using a mosaic of five separate pointings with XMM-Newton. Our observations allow for robust measurements of the temperature and metallicity structure of each galaxy along with the entire ~ 1 degree region between these galaxies. When combined with multiwavelength observations, the data suggest that all four of these galaxies are undergoing ram pressure stripping by the Intracluster Medium (ICM). The manner in which the stripped gas trailing the galaxies interacts with the ICM, however, is observably distinct. Consistent with previous observations, M86 is observed to have a long tail of ~ 1 keV gas trailing to the north-west for distances of ~ 100-150 kpc. However, a new site of ~ 0.6 keV thermal emission is observed to span to the east of M86 in the direction of the disturbed spiral galaxy NGC 4438. This region is spatially coincident with filaments of H-alpha emission, likely originating in a recent collision between the two galaxies. We also resolve the thermodynamic structure of stripped ~ 0.6 keV gas to the south of M84, suggesting that this galaxy is undergoing both AGN feedback and ram pressure stripping simultaneously. These four sites of stripped X-ray gas demonstrate that the nature of ram pressure stripping can vary significantly from site to site.Comment: 10 pages, 5 figures. Please contact Steven Ehlert ([email protected]) for higher resolution figure

    Ongoing Gas Stripping in the Virgo Cluster Spiral NGC 4522

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    The Virgo cluster galaxy NGC 4522 is one of the best spiral candidates for ICM-ISM stripping in action. Optical broadband and H-alpha images from the WIYN telescope of the highly inclined galaxy reveal a relatively undisturbed stellar disk and a peculiar distribution of H-alpha emission. Ten percent of the H-alpha emission arises from extraplanar HII regions which appear to lie within filamentary structures >3 kpc long above one side of the disk. The filaments emerge from the outer edge of a disk of bright H-alpha emission which is abruptly truncated beyond 0.35R(25). Together the truncated H-alpha disk and extraplanar H-alpha filaments are reminiscent of a bow shock morphology, which strongly suggests that the interstellar medium (ISM) of NGC 4522 is being stripped by the gas pressure of the intracluster medium (ICM). The galaxy has a line-of-sight velocity of 1300 km/sec with respect to the mean Virgo cluster velocity, and thus is expected to experience a strong interaction with the intracluster gas. The existence of HII regions apparently located above the disk plane suggests that star formation is occuring in the stripped gas, and that newly formed stars will enter the galaxy halo and/or intracluster space. The absence of HII regions in the disk beyond 0.35R(25), and the existence of HII regions in the stripped gas suggest that even molecular gas has been effectively removed from the disk of the galaxy.Comment: to appear in The Astronomical Journal, 16 pages, 5 figures, 1 tabl

    Invest to Save: Report and Recommendations of the NSF-DELOS Working Group on Digital Archiving and Preservation

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    Digital archiving and preservation are important areas for research and development, but there is no agreed upon set of priorities or coherent plan for research in this area. Research projects in this area tend to be small and driven by particular institutional problems or concerns. As a consequence, proposed solutions from experimental projects and prototypes tend not to scale to millions of digital objects, nor do the results from disparate projects readily build on each other. It is also unclear whether it is worthwhile to seek general solutions or whether different strategies are needed for different types of digital objects and collections. The lack of coordination in both research and development means that there are some areas where researchers are reinventing the wheel while other areas are neglected. Digital archiving and preservation is an area that will benefit from an exercise in analysis, priority setting, and planning for future research. The WG aims to survey current research activities, identify gaps, and develop a white paper proposing future research directions in the area of digital preservation. Some of the potential areas for research include repository architectures and inter-operability among digital archives; automated tools for capture, ingest, and normalization of digital objects; and harmonization of preservation formats and metadata. There can also be opportunities for development of commercial products in the areas of mass storage systems, repositories and repository management systems, and data management software and tools.
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