9,691 research outputs found
Instantaneous Dynamics of QCD
We start from the observation that, in the confining phase of QCD, the
instantaneous color-Coulomb potential in Coulomb gauge is confining. This
suggests that, in the confining phase, the dynamics, as expressed in the set of
Schwinger-Dyson equations, may be dominated by the purely instantaneous terms.
We develop a calculational scheme that expresses the instantaneous dynamics in
the local formulation of QCD that includes a cut-off at the Gribov horizon.Comment: 7 pages, 3 figures, Talk given at conference XIIth Quark Confinement
and the Hadron Spectrum, 28 August to 4 September, 2016, Thessaloniki,
Greece, talk dedicated to the memory of Martin Schade
Assessments as Teaching and Research Tools in an Environmental Problem-Solving Program for In-Service Teachers
This article discusses the use of a scenario-based assessment tool in two environmental geoscience in-service programs for middle school and high school teachers. This tool served both to guide instructional techniques and as a method to evaluate the success of the instructional approach. In each case, participants were assessed before the workshops to reveal misconceptions that could be addressed in program activities and afterwards to reveal shifts in their understanding of concepts and approaches. The researchers noted that this scenario-based assessment was effective in providing guidance in refining instructional techniques and as a method to evaluate the effectiveness of an instructional program. In addition, participating teachers reported significant changes in their teaching as a result of the program. Educational levels: Graduate or professional, Graduate or professional
Development of a machine vision system for automated structural assembly
Research is being conducted at the LaRC to develop a telerobotic assembly system designed to construct large space truss structures. This research program was initiated within the past several years, and a ground-based test-bed was developed to evaluate and expand the state of the art. Test-bed operations currently use predetermined ('taught') points for truss structural assembly. Total dependence on the use of taught points for joint receptacle capture and strut installation is neither robust nor reliable enough for space operations. Therefore, a machine vision sensor guidance system is being developed to locate and guide the robot to a passive target mounted on the truss joint receptacle. The vision system hardware includes a miniature video camera, passive targets mounted on the joint receptacles, target illumination hardware, and an image processing system. Discrimination of the target from background clutter is accomplished through standard digital processing techniques. Once the target is identified, a pose estimation algorithm is invoked to determine the location, in three-dimensional space, of the target relative to the robots end-effector. Preliminary test results of the vision system in the Automated Structural Assembly Laboratory with a range of lighting and background conditions indicate that it is fully capable of successfully identifying joint receptacle targets throughout the required operational range. Controlled optical bench test results indicate that the system can also provide the pose estimation accuracy to define the target position
Coastal Capital -- Economic Valuation of Coral Reefs in Tobago and St. Lucia
Presents findings on the economic benefits of coral reefs to the local economies of Tobago and St. Lucia, using a new, broadly applicable methodology that focuses on benefits to tourism, fisheries, and shoreline protection. Includes policy applications
Anxiety, Nostalgia, And Mistrust: Findings from the 2015 American Values Survey
The nonpartisan Public Religion Research Institute (PRRI) conducted the 2015 American Values Survey among 2,695 Americans between September 11 and October 4, 2015. The sixth annual AVS measures public opinion about the economy, racial discrimination, the criminal justice system, trust in public institutions, perception of the Tea Party, the relationship between religious affiliation and political attitudes, views of immigrants, and how demographic changes impact the cultural landscape in the country
A Penny Saved Is Mobility Earned
Analyzes data on how one's or one's parents' level of savings affects economic mobility, by income; examines savings incentives and disincentives in the federal tax code and public assistance programs; and recommends policy options to encourage savings
Beyond Same-Sex Marriage: Attitudes on LGBT Nondiscrimination Laws and Religious Exemptions - Finding from the 2015 American Values Atlas
Across 2015, the year that saw same-sex marriage become legal in all 50 states following the landmark Obergefell v. Hodges Supreme Court decision in June, public opinion on same-sex marriage remained remarkably stable. Based on interviews with more than 42,000 Americans conducted between May and December 2015, PRRI finds that 53% of Americans support allowing gay and lesbian people to legally marry, while 37% are opposed.In surveys conducted during May 2015, the month before the Supreme Court decision, 53% of the public on average supported same-sex marriage. Weekly tracking polls showed no significant shift in opinion as a result of the court decision, with the June average showing 55% support and the July average showing 53% support
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