974 research outputs found
Geostatistical analysis of an experimental stratigraphy
[1] A high-resolution stratigraphic image of a flume-generated deposit was scaled up to sedimentary basin dimensions where a natural log hydraulic conductivity (ln( K)) was assigned to each pixel on the basis of gray scale and conductivity end-members. The synthetic ln( K) map has mean, variance, and frequency distributions that are comparable to a natural alluvial fan deposit. A geostatistical analysis was conducted on selected regions of this map containing fluvial, fluvial/ floodplain, shoreline, turbidite, and deepwater sedimentary facies. Experimental ln(K) variograms were computed along the major and minor statistical axes and horizontal and vertical coordinate axes. Exponential and power law variogram models were fit to obtain an integral scale and Hausdorff measure, respectively. We conclude that the shape of the experimental variogram depends on the problem size in relation to the size of the local-scale heterogeneity. At a given problem scale, multilevel correlation structure is a result of constructing variogram with data pairs of mixed facies types. In multiscale sedimentary systems, stationary correlation structure may occur at separate scales, each corresponding to a particular hierarchy; the integral scale fitted thus becomes dependent on the problem size. The Hausdorff measure obtained has a range comparable to natural geological deposits. It increases from nonstratified to stratified deposits with an approximate cutoff of 0.15. It also increases as the number of facies incorporated in a problem increases. This implies that fractal characteristic of sedimentary rocks is both depositional process - dependent and problem-scale-dependent
College-Ready Urban Black, Hispanic, and Biracial Students: Why Are They Not Applying to College?
The study explored reasons why Black, Hispanic, and Biracial, first generation high school seniors who wish to attend college, do not apply. The literature indicated that these populations have consistently lower rates of college enrollment and educational attainment than Whites and Asians (Ashburn, 2008). Enrollment challenges included deficiencies in the areas of academic readiness (Forster, 2006), college knowledge (Tierney & Venegas, 2009), parental engagement (Auerbach, 2007), access to guidance counselors (Farmer-Hinton & Holland, 2008), and social capital (Burleson, Hallett, & Park, 2008). Future growth rates in American higher education will be spurred by those who are least educated and most economically disadvantaged (Epstein & Parrot, 2009). ^ Research was conducted through the lens of social capital acquired through resources internal and external to school environments. The research questions explored how environmental factors positively or negatively influenced college aspirations, knowledge of college admissions and financial aid processes, and other enrollment challenges. ^ Phase one of this mixed methods sequential explanatory design study collected quantitative data from N=26 seniors from two high schools in New England using a 25 question college interest survey instrument. The survey results assisted with the selection of the final n=18 first generation students were college eligible , but had not yet applied. The survey results also facilitated the development of focus group questions for phase two. Participants for the focus groups totaled n=11; five from one high school and six from the other. Focus group questions were designed to more fully examine quantitative data results. ^ Results were analyzed with frequencies, percents, means, and standard deviations to describe levels of college knowledge, parental involvement of college processes, perceptions of college preparedness, participation in readiness activities, and counselor access. Primary findings indicated that concerns about college financing were constant, parents had low levels of involvement with college processes, few students had engaged in college support programs, and students relied heavily on counselors for college assistance. ^ Potential actions focus on community based support networks to increase parent learning opportunities, developing a guide to assist with basic college processes, and access to college campuses to provide students with information and experiential learning opportunities.
HTC Scientific Computing in a Distributed Cloud Environment
This paper describes the use of a distributed cloud computing system for
high-throughput computing (HTC) scientific applications. The distributed cloud
computing system is composed of a number of separate
Infrastructure-as-a-Service (IaaS) clouds that are utilized in a unified
infrastructure. The distributed cloud has been in production-quality operation
for two years with approximately 500,000 completed jobs where a typical
workload has 500 simultaneous embarrassingly-parallel jobs that run for
approximately 12 hours. We review the design and implementation of the system
which is based on pre-existing components and a number of custom components. We
discuss the operation of the system, and describe our plans for the expansion
to more sites and increased computing capacity
Recommended from our members
Exploring content and psychometric validity of newly developed assessment tools for itch and skin pain in atopic dermatitis.
BackgroundAtopic dermatitis (AD) is a common skin disorder characterized by chronic inflammation, altered skin barrier function, and inflammatory cell skin infiltration that decreases health-related quality of life (HRQoL). The study objective was to understand the patient perspective of AD burden and determine suitable patient-reported outcome (PRO) measures.MethodsThis mixed methods study involved the collection of qualitative and quantitative information from adults (â„Â 18âyears old) and adolescents (12Â -Â 17âyears old) with clinician-confirmed AD regarding their experiences of AD symptoms and its impact on HRQoL. The first part of the study included three stages: in-person concept elicitation (CE) interviews, a 2-week daily electronic diary (eDiary) study, and in-person cognitive debriefing (CD) interviews. An Itch numeric rating scale (NRS) (v1.0) and a Skin Pain NRS (v1.0) evaluation during CD interviews required participants to think about their 'worst' itch and 'worst' skin pain in the past 24âh. Other PRO measures allowed for psychometric testing. The second part of the study involved telephone-depth interviews (TDIs) and qualitative feedback from participants who had not participated in the CD interviews. Qualitative data were thematically analyzed. Psychometric evaluation of NRS measures was performed using eDiary data.ResultsIn the CE interviews, itch and/or itching and skin pain were the most prevalent symptoms consistently discussed by participants. Both NRS measures demonstrated strong psychometric reliability and were applicable across ages with suitable concurrent validity. During the CD interviews, some participants focused their answers on their 'average' itch/itching in the past 24âh, rather than their 'worst' itch. Some participants answered the Skin Pain NRS thinking about general pain or other types of pain, rather than skin pain specifically. Consequently, modifications to both measures addressed these issues and re-tested as paper-and-pen versions in subsequent TDIs. Itch NRS (v2.0) modifications helped participants focus on their worst itching. Most participants preferred Skin Pain NRS v2.0b, which included skin pain descriptors.ConclusionsItching and skin pain are the most important and relevant AD symptoms. The Itch NRS (v2.0) and Skin Pain NRS (v2.0b) appear to be appropriate endpoints for the assessment of itching and skin pain severity for clinical trials with adults and adolescents with AD
Recommended from our members
Automated grid generation from models of complex geologic structure and stratigraphy
The construction of computational grids which accurately reflect complex geologic structure and stratigraphy for flow and transport models poses a formidable task. With an understanding of stratigraphy, material properties and boundary and initial conditions, the task of incorporating this data into a numerical model can be difficult and time consuming. Most GIS tools for representing complex geologic volumes and surfaces are not designed for producing optimal grids for flow and transport computation. We have developed a tool, GEOMESH, for generating finite element grids that maintain the geometric integrity of input volumes, surfaces, and geologic data and produce an optimal (Delaunay) tetrahedral grid that can be used for flow and transport computations. GEOMESH also satisfies the constraint that the geometric coupling coefficients of the grid are positive for all elements. GEOMESH generates grids for two dimensional cross sections, three dimensional regional models, represents faults and fractures, and has the capability of including finer grids representing tunnels and well bores into grids. GEOMESH also permits adaptive grid refinement in three dimensions. The tools to glue, merge and insert grids together demonstrate how complex grids can be built from simpler pieces. The resulting grid can be utilized by unstructured finite element or integrated finite difference computational physics codes
Sparrows can't sing : East End kith and kinship in the 1960s
Sparrows Canât Sing (1963) was the only feature film directed by
the late and much lamented Joan Littlewood. Set and filmed in
the East End, where she worked for many years, the film deserves
more attention than it has hitherto received. Littlewoodâs career
spanned documentary (radio recordings made with Ewan MacColl
in the North of England in the 1930s) to directing for the stage
and the running of the Theatre Royal in Londonâs Stratford East,
often selecting material which aroused memories in local audiences
(Leach 2006: 142). Many of the actors trained in her Theatre
Workshop subsequently became better known for their appearances
on film and television. Littlewood herself directed hardly any material
for the screen: Sparrows Canât Sing and a 1964 series of television
commercials for the British Egg Marketing Board, starring Theatre
Workshopâs Avis Bunnage, were rare excursions into an area of practice
which she found constraining and unamenable (Gable 1980: 32).
The hybridity and singularity of Littlewoodâs feature may answer,
in some degree, for its subsequent neglect. However, Sparrows Canât
Sing makes a significant contribution to a group of films made in
Britain in the 1960s which comment generally on changes in the
urban and social fabric. It is especially worthy of consideration,
I shall argue, for the use which Littlewood made of a particular
communityâs attitudes â sentimental and critical â to such changes and
for its amalgamation of an attachment to documentary techniques
(recording an aural landscape on location) with a preference for nonnaturalistic
delivery in performance
- âŠ