Iterchanging Discrete Event Simulationprocess Interaction Modelsusing The Web Ontology Language - Owl

Discrete event simulation development requires significant investments in time and resources. Descriptions of discrete event simulation models are associated with world views, including the process interaction orientation. Historically, these models have been encoded using high-level programming languages or special purpose, typically vendor-specific, simulation languages. These approaches complicate simulation model reuse and interchange. The current document-centric World Wide Web is evolving into a Semantic Web that communicates information using ontologies. The Web Ontology Language OWL, was used to encode a Process Interaction Modeling Ontology for Discrete Event Simulations (PIMODES). The PIMODES ontology was developed using ontology engineering processes. Software was developed to demonstrate the feasibility of interchanging models from commercial simulation packages using PIMODES as an intermediate representation. The purpose of PIMODES is to provide a vendor-neutral open representation to support model interchange. Model interchange enables reuse and provides an opportunity to improve simulation quality, reduce development costs, and reduce development times

An Infrared Comparison of Type-1 and Type-2 Quasars

We model the optical to far-infrared SEDs of a sample of six type-1 and six type-2 quasars selected in the mid-infrared. The objects in our sample are matched in mid-IR luminosity and selected based on their Spitzer IRAC colors. We obtained new targeted Spitzer IRS and MIPS observations and used archival photometry to examine the optical to far-IR SEDs. We investigate whether the observed differences between samples are consistent with orientation-based unification schemes. The type-1 objects show significant emission at 3 micron. They do not show strong PAH emission and have less far-IR emission on average when compared to the type-2 objects. The SEDs of the type-2 objects show a wide assortment of silicate features, ranging from weak emission to deep silicate absorption. Some also show strong PAH features. In comparison, silicate is only seen in emission in the type-1 objects. This is consistent with some of the type-2s being reddened by a foreground screen of cooler dust, perhaps in the host galaxy itself. We investigate the AGN contribution to the far-IR emission and find it to be significant. We also estimate the star formation rate for each of the objects by integrating the modeled far-IR flux and compare this with the SFR found from PAH emission. We find the type-2 quasars have a higher average SFR than the type-1 quasars based on both methods, though this could be due to differences in bolometric luminosities of the objects. While we find pronounced differences between the two types of objects, none of them are inconsistent with orientation-based unification schemes.Comment: Accepted for publication in Ap

Creating Accessible Websites: Developing a Fire Safety Website for Teenagers Who Are Deaf or Hard of Hearing

This study used three research phases to create an effective fire safety website for deaf teenagers. Participants were students in grades 7-12 from the Oklahoma School for the Deaf. First, 50 students responded to a questionnaire measuring their fire safety knowledge and interests along with their internet use and preferences. For the second phase, 50 students evaluated nine of the current fire safety sites via guided worksheets, and I performed a content analysis of the same nine sites. The third phase, with a stratified selection of 20 students, involved testing the new fire safety site through think-aloud interviews, half of which were conducted via Instant Messaging software to determine whether IM is a feasible tool for usability studies. Deaf teenagers have unique fire safety information needs and internet preferences. Many were unaware of specialized smoke alarms, and they wanted more information about careers for deaf people in the fire service. Of the nine sites tested, none contained information customized to helping a deaf teenager plan effectively for fire emergencies, and many of the sites violated the accessibility guidelines outlined by the World Wide Web Consortium, especially as they used audio features without captions. Six of the websites used vocabulary levels well above the recommended fourth grade reading level for deaf teenagers, and eight sites were too juvenile in tone to appeal to this audience. Echoing the design and navigation aspects of Yahoo and MySpace, the new fire safety website scored well above the other websites tested and received positive feedback from the students. An overwhelming majority of students found the site's words and pictures easy to understand and relevant to their needs, and all the students said they would recommend it to their friends. IM also proved a useful tool for usability studies because the chat transcript shows the students' natural search terms and language structure. But when using IM, researchers must be prepared to rephrase questions and to decipher responses written in text message and TTY codes. Finally, a list of recommended fire safety vocabulary is included as part of the study's conclusions.English Departmen

Searching For Transiting Circumbinary Planets in CoRoT and Ground-Based Data Using CB-BLS

Aims. We search for transiting circumbinary (CB) planets around eclipsing binaries (EBs). Methods. CB-BLS is a recently-introduced algorithm for the detection of transiting CB planets around EBs.We describe progress in search sensitivity, generality and capability of CB-BLS, and detection tests of CB-BLS on simulated data. We also describe an analytical approach for the determination of CB-BLS detection limits, and a method for the correct detrending of intrinsically-variable stars. Results. We present some blind-tests with simulated planets injected to real CoRoT data. The presented upgrades to CB-BLS allowed it to detect all the blind tests successfully, and these detections were in line with the detection limits analysis. We also correctly detrend bright eclipsing binaries from observations by the TrES planet search, and present some of the first results of applying CB-BLS to multiple real light curves from a wide-field survey. Conclusions. CB-BLS is now mature enough for its application to real data, and the presented processing scheme will serve as the template for our future applications of CB-BLS to data from wide-field surveys such as CoRoT. Being able to put constraints even on non-detection will help to determine the correct frequency of CB planets, contributing to the understanding of planet formation in general. Still, searching for transiting CB planets is still a learning experience, similarly to the state of transiting planets around single stars only a few years ago. The recent rapid progress in this front, coupled with the exquisite quality of space-based photometry, allows to realistically expect that if transiting CB planets exist - then they will soon be found.Comment: A&A accepted. Presented at the 1st CoRoT symposium. Note table 3 is too wide in this version, but omitted data is of minor significance. 10 pages, 10 figures, 3 table

Hyper-Velocity Impact Performance of Foldcore Sandwich Composites

A foldcore is a novel core made from a flat sheet of any material folded into a desired pattern. A foldcore sandwich composite (FSC) provides highly tailorable structural performance over conventional sandwich composites made with honeycomb or synthetic polymer foam cores. Foldcore design can be optimized to accommodate complex shapes and unit cell geometries suitable for protective shielding structures This work aims to characterize hypervelocity impact (\u3e 2000 m/s, HVI) response and corresponding damage morphologies of carbon fiber reinforced polymer (CFRP) FSCs. A series of normal (0° impact angle) and oblique (45° impact angle) HVI (~3km/s nominal projectile velocity) impact tests were performed on CFRP FSC targets to understand the effects of projectile impact on redirected debris formation, and variable debris cloud expansion. HVI damage in FSC targets were assessed using visual inspection and high-speed imaging analysis. The results from the present study indicate that debris cloud propagation and expansion are strongly influenced by foldcore impact location/angle and open-channel direction. This work serves as a baseline study to understand HVI response of FSC targets and to identify critical FSC design parameters to optimize HVI mitigation performance

TheamnGene Product Is Required in Extraembryonic Tissues for the Generation of Middle Primitive Streak Derivatives

AbstractThe primitive streak is the defining feature of the gastrulating mouse embryo. Currently, little is known in the mouse about the mechanisms that mediate the assembly of the primitive streak or about the signaling pathways that specify the different types of mesoderm and endoderm generated from the streak. To gain insight into primitive streak assembly and function, we have conducted a detailed phenotypic characterization ofamnionless,a transgene-induced insertional mouse mutation that arrests embryonic development during gastrulation. Our histological and molecular analyses, when examined in the context of the mouse gastrula fate map, lead to the model that middle streak formation is specifically impaired in theamnionlessmutant. Significantly, these observations argue that the formation of the middle streak is mediated by a pathway that is genetically separable from those that direct the specification of the distal and proximal streak regions. Intriguingly, our findings from wt ES cell ↔amnionless−/−blastocyst chimeras indicate that this proposed separate pathway for middle streak formation is dependent onamnionlessgene functions in the visceral endoderm