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Report in Response to America COMPETES Act: SEC. 7022

Description: This report is written in response to the America COMPETES Act request that the NSF Director report on the NSF broader impact merit review criterion. This report includes background on the NSF implementation of the broader impact criterion and responds to each of the five specific requests made in the COMPETES Act Sec 7022.
Date: 2008
Creator: National Science Foundation (U.S.)
Partner: UNT Libraries Government Documents Department

New Source of Natural Fertilizer Discovered in Oceans

Description: New findings suggest that the deep ocean is teeming with organisms that produce essential natural fertilizers. A National Science Foundation (NSF)-funded research team led by Jonathan Zehr, a marine scientist at the University of California, Santa Cruz, has discovered a previously unknown type of photosynthetic bacteria that fixes nitrogen, converting nitrogen from the atmosphere into a form other organisms can use.
Date: August 8, 2001
Creator: National Science Foundation (U.S.). Office of Legislative and Public Affairs.
Partner: UNT Libraries

Ethics Gaming Survey Results

Description: Dataset generated for a National Science Foundation grant project, "EAGER: Prototyping a Virtue Ethics Game." These files contain the research results of the pre-test and post-test surveys.
Date: August 29, 2013
Creator: Oppong, Joseph R.
Partner: UNT College of Arts and Sciences

NMR studies of DNA oligomers and their interactions with minor groove binding ligands

Description: The cationic peptide ligands distamycin and netropsin bind noncovalently to the minor groove of DNA. The binding site, orientation, stoichiometry, and qualitative affinity of distamycin binding to several short DNA oligomers were investigated by NMR spectroscopy. The oligomers studied contain A,T-rich or I,C-rich binding sites, where I = 2-desaminodeoxyguanosine. I{center_dot}C base pairs are functional analogs of A{center_dot}T base pairs in the minor groove. The different behaviors exhibited by distamycin and netropsin binding to various DNA sequences suggested that these ligands are sensitive probes of DNA structure. For sites of five or more base pairs, distamycin can form 1:1 or 2:1 ligand:DNA complexes. Cooperativity in distamycin binding is low in sites such as AAAAA which has narrow minor grooves, and is higher in sites with wider minor grooves such as ATATAT. The distamycin binding and base pair opening lifetimes of I,C-containing DNA oligomers suggest that the I,C minor groove is structurally different from the A,T minor groove. Molecules which direct chemistry to a specific DNA sequence could be used as antiviral compounds, diagnostic probes, or molecular biology tools. The author studied two ligands in which reactive groups were tethered to a distamycin to increase the sequence specificity of the reactive agent.
Date: May 1, 1996
Creator: Fagan, P.A.
Partner: UNT Libraries Government Documents Department

Microbial ecology of terrestrial Antarctica: Are microbial systems at risk from human activities?

Description: Many of the ecological systems found in continental Antarctica are comprised entirely of microbial species. Concerns have arisen that these microbial systems might be at risk either directly through the actions of humans or indirectly through increased competition from introduced species. Although protection of native biota is covered by the Protocol on Environmental Protection to the Antarctic Treaty, strict measures for preventing the introduction on non-native species or for protecting microbial habitats may be impractical. This report summarizes the research conducted to date on microbial ecosystems in continental Antarctica and discusses the need for protecting these ecosystems. The focus is on communities inhabiting soil and rock surfaces in non-coastal areas of continental Antarctica. Although current polices regarding waste management and other operations in Antarctic research stations serve to reduce the introduction on non- native microbial species, importation cannot be eliminated entirely. Increased awareness of microbial habitats by field personnel and protection of certain unique habitats from physical destruction by humans may be necessary. At present, small-scale impacts from human activities are occurring in certain areas both in terms of introduced species and destruction of habitat. On a large scale, however, it is questionable whether the introduction of non-native microbial species to terrestrial Antarctica merits concern.
Date: August 1, 1996
Creator: White, G.J.
Partner: UNT Libraries Government Documents Department

Electromagnetic waves in a strong Schwarzschild plasma

Description: The physics of high frequency electromagnetic waves in a general relativistic plasma with the Schwarzschild metric is studied. Based on the 3 + 1 formalism, we conformalize Maxwell`s equations. The derived dispersion relations for waves in the plasma contain the lapse function in the plasma parameters such as in the plasma frequency and cyclotron frequency, but otherwise look {open_quotes}flat.{close_quotes} Because of this property this formulation is ideal for nonlinear self-consistent particle (PIC) simulation. Some of the physical consequences arising from the general relativistic lapse function as well as from the effects specific to the plasma background distribution (such as density and magnetic field) give rise to nonuniform wave equations and their associated phenomena, such as wave resonance, cutoff, and mode-conversion. These phenomena are expected to characterize the spectroscopy of radiation emitted by the plasma around the black hole. PIC simulation results of electron-positron plasma are also presented.
Date: November 1, 1996
Creator: Daniel, J. & Tajima, T.
Partner: UNT Libraries Government Documents Department

Copper Mountain conference on multigrid methods. Preliminary proceedings -- List of abstracts

Description: This report contains abstracts of the papers presented at the conference. Papers cover multigrid algorithms and applications of multigrid methods. Applications include the following: solution of elliptical problems; electric power grids; fluid mechanics; atmospheric data assimilation; thermocapillary effects on weld pool shape; boundary-value problems; prediction of hurricane tracks; modeling multi-dimensional combustion and detailed chemistry; black-oil reservoir simulation; image processing; and others.
Date: December 31, 1995
Partner: UNT Libraries Government Documents Department

Mitigation of earthquake hazards using seismic isolation systems

Description: This paper describes mitigation of earthquake hazards using seismic base isolation systems. A numerical algorithm for analyzing system response of base-isolated structures with laminated elastomer bearings is briefly described. Seismic response analyses of both base- isolated and unisolated buildings under earthquakes {number_sign}42 and {number_sign}44 are performed and the results are compared to illustrate the mitigating effect of base-isolated systems.
Date: June 1, 1996
Creator: Wang, C.-Y.
Partner: UNT Libraries Government Documents Department

Computational modeling of material aging effects

Description: Progress is being made in our efforts to develop computational models for predicting material property changes in weapon components due to aging. The first version of a two-dimensional lattice code for modeling thermomechanical fatigue, such as has been observed in solder joints on electronic components removed from the stockpile, has been written and tested. The code does a good qualitative job of presenting intergranular and/or transgranular cracking in a polycrystalline material when under thermomechanical deformation. The current progress is an encouraging start for our long term effort to develop multi-level simulation capabilities, with the technology of high performance computing, for predicting age-related effects on the reliability of weapons.
Date: July 1, 1996
Creator: Fang, H.E.
Partner: UNT Libraries Government Documents Department

The Promise and Perils of Transformative Research

Description: This report is on the workshop 'Transformative Research: Ethical and Societal Implications'. Workshop conversations cluster under the four headings of the history and definitions, promotion, evaluation, and integration of transformative research.
Date: March 2012
Creator: Frodeman, Robert & Holbrook, J. Britt
Partner: UNT College of Arts and Sciences

The National Teacher Enhancement Program (K-8) coordinated by the Oak Ridge National Laboratory

Description: Teachers need help, not harassment. So do the establishments in which teachers practice their profession. Community resources must be marshalled to provide help to local schools and teachers. In 1990 the National Science Foundation (NSF) established a unique educational activity named the National Teacher Enhancement Program (NTEP). NSF took advantage of the Department of Energy (DOE) sponsored educational programs and resources at several large DOE contractor labs that had had prior experience with DOE supported teacher enhancement programs. While DOE concentrated on teacher enhancement activities for secondary teachers, the NSF concentrated on teachers from grades K-8. The Oak Ridge National Laboratory (ORNL) is the lead organization for both administering and coordinating the grant. Other participating laboratories are Argonne National Laboratory (ANL), Fermi National Accelerator Laboratory (FERMI), Battelle-Pacific Northwest Laboratory (PNL), Lawrence Livermore Laboratory (LLNL) with some support functions provided by Brookhaven National Laboratory (BNL) and the Oak Ridge Associated Universities (ORAU). The program calls for a three week duration workshop to be conducted at each lab followed by in-service training and other activities during the year. The NSF/NTEP protocol calls for networking among the participating organizations and some of the teachers. An assessment effort is also an integral part of the program. 2 refs.
Date: January 1, 1991
Creator: Richmond, C.R.
Partner: UNT Libraries Government Documents Department

Nuclear/High Energy Physics (NuHEP) research center of excellence

Description: This report contains the manuscripts from the proceedings of the third annual Undergraduate Institute in Physics Program. The titles of these manuscripts are: flow measurements for the hall c cryogenic target loops; calibrations for the hall c drift chambers gas mixing system; the electromagnetic structure of the nucleon; investigation of drift chambers in hall c at CEBAF; seek and ye shall find; commissioning techniques; and instruments used in particle detection.
Date: December 31, 1994
Partner: UNT Libraries Government Documents Department

[Atomic and electronic structure of metals and alloys: Clean surfaces and chemisorbed molecules]

Description: Ultrapure Tb was further purified and surface cleaning procedures developed for basal plane and (11[bar 2]0) surface of Tb. Structure of both surfaces was found to be relaxed: (0001) is contracted by 3.9% in the first and expanded by 1.4% in second interlayer spacing; (11[bar 2]0) is contracted by 3.3% in first layer and shows a change in registry. Thin films of Gd, Tb, Dy, Ho, and Er were grown on W[l brace]110[r brace] substrate in ultrahigh vacuum. Studies have been carried out on epitaxial systems involving Cu, Fe and Mn on Fe and Pt, Cu, and Pd substrates, respectively; new metastable crystalline phases have been found. Studies of possible ferromagnetism in 4d elements (Rh, Ru) and relativistic effects in electron band structure of Cu[l brace]111[r brace] have been completed and published. Plans for the following year are given.
Date: January 1, 1993
Partner: UNT Libraries Government Documents Department

Application of ground-penetrating radar at McMurdo Station, Antarctica

Description: Argonne National Laboratory initiated a site investigation program at McMurdo Station, Antarctica, to characterize environmental contamination. The performance and usefulness of ground-penetrating radar (GPR) was evaluated under antarctic conditions during the initial site investigation in January 1991. Preliminary surveys were successful in defining the contact between reworked pyroclastic material and in the prefill, undisturbed pyroclastics and basalts at some sites. Interference from radio traffic at McMurdo Station was not observed, but interference was a problem in work with unshielded antennas near buildings. In general, the results of this field test suggest that high-quality, high-resolution, continuous subsurface profiles can be produced with GPR over most of McMurdo Station.
Date: January 1, 1992
Creator: Stefano, J.E.
Partner: UNT Libraries Government Documents Department

Comparison of SISEC code simulations with earthquake data of ordinary and base-isolated buildings

Description: Seismic isolation is gaining attention worldwide for use in a wide spectrum of structures and critical facilities, including bridges, office buildings, hospitals, computing and telecommunication centers, as well as nuclear facilities. Today there are over 125 structures worldwide which are isolated and the numbers have been increasing steadily in the past few years. Also, substantial research efforts have been devoted to the designs, testing of isolation bearings, as well as development of analytical methods for predicting the responses of isolated structures. At Argonne National Laboratory (ANL), a 3-D computer program SISEC (Seismic Isolation System Evaluation Code) is being developed for simulating the system response of isolated and ordinary structures (Wang et al. 1991). This paper describes comparison of SISEC code simulations with building response data of actual earthquakes. To ensure the accuracy of analytical simulations, recorded data of full-size reinforced concrete structures located in Sendai, Japan are used in this benchmark comparison. The test structures consist of two three-story buildings, one base-isolated and the other one ordinary founded. They were constructed side by side to investigate the effect of base isolation on the acceleration response. Among 20 earthquakes observed since April 1989, complete records of three representative earthquakes, Nos. 2, 6, and 17, are used for the code validation presented in this paper. Correlations of observed and calculated accelerations at all instrument locations are made. Also, relative response characteristics of ordinary and isolated building structures are investigated. 3 refs., 5 figs., 1 tab.
Date: January 1, 1991
Creator: Wang, C.Y. & Gvildys, J.
Partner: UNT Libraries Government Documents Department

Grid Simulator for Testing a Wind Turbine on Offshore Floating Platform

Description: An important aspect of such offshore testing of a wind turbine floating platform is electrical loading of the wind turbine generator. An option of interconnecting the floating wind turbine with the onshore grid via submarine power cable is limited by many factors such as costs and associated environmental aspects (i.e., an expensive and lengthy sea floor study is needed for cable routing, burial, etc). It appears to be a more cost effective solution to implement a standalone grid simulator on a floating platform itself for electrical loading of the test wind turbine. Such a grid simulator must create a stable fault-resilient voltage and frequency bus (a micro grid) for continuous operation of the test wind turbine. In this report, several electrical topologies for an offshore grid simulator were analyzed and modeled.
Date: February 1, 2012
Creator: Gevorgian, V.
Partner: UNT Libraries Government Documents Department

LSND, SN1987A, and CPT violation

Description: We point out that neutrino events observed at Kamiokande andIMB from SN1987A disfavor the neutrino oscillation parameters preferredby the LSND experiment. For Delta m2>0 (the light side), theelectron neutrinos from the neutronization burst would be lost, while thefirst event at Kamiokande is quite likely to be due to an electronneutrino. For Delta m2<0 (the dark side), the average energy of thedominantly bar nu e events is already lower than the theoreticalexpectations, which would get aggravated by a complete conversion frombar nu mu to bar nu e. If taken seriously, the LSND data are disfavoredindependent of the existence of a sterile neutrino. A possible remedy isCPT violation, which allows different mass spectra for neutrinos andanti-neutrinos and hence can accommodate atmospheric, solar and LSND datawithout a sterile neutrino. If this is the case, Mini-BooNE must run inbar nu rather than the planned nu mode to test the LSND signal. Wespeculate on a possible origin of CPT violation.
Date: October 17, 2000
Creator: Murayama, Hitoshi & Yanagida, T.
Partner: UNT Libraries Government Documents Department

Confinement and flavor symmetry breaking via monopolecondensation

Description: We discuss dynamics of N=2 supersymmetric SU(n_c) gaugetheories with n_f quark hypermultiplets. Upon N=1 perturbation ofintroducing a finite mass for the adjoint chiral multiplet, we show thatthe flavor U(n_f) symmetry is dynamically broken to U(r) times U(n_f-r),where r\leq [n_f/2]is an integer. This flavor symmetry breaking occursdue to the condensates of magnetic degrees of freedom which acquireflavor quantum numbers due to the quark zero modes. We briefly comment onthe USp(2n_c) gauge theories. This talk is based on works with GiuseppeCarlino and Ken Konishi, hep-th/0001036 and hep-th/0005076.
Date: September 19, 2000
Creator: Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department

Demand Controlled Ventilation using CO2 Sensors in a Wireless Sensor Network [Poster]

Description: Poster presented as part of the 2013 Research Experiences for Teachers (RET) in Sensor Education, a National Science Foundation (NSF) funded grant project. This poster discusses research on demand controlled ventilation using CO₂ sensors in a wireless sensor network.
Date: 2013
Creator: Parsons, David; Jordan, Georgette; Li, Xinrong; Thompson, Ruthanne & Abraham, Sherin
Partner: UNT College of Engineering

Demand Controlled Ventilation using CO₂ Sensors in a Wireless Sensor Network

Description: This report discusses research on demand controlled ventilation using CO₂ sensors in a wireless sensor network. The focus of this research project was to investigate Indoor Air Quality (IAQ) monitoring technologies, government regulations and policies, and best practices to improve IAQ. This research is part of Research Experiences for Teachers (RET) in Sensor Education, a National Science Foundation (NSF) funded grant project.
Date: 2013
Creator: Parsons, David; Jordan, Georgette; Li, Xinrong; Thompson, Ruthanne & Abraham, Sherin
Partner: UNT College of Engineering

Robotics: Cooperation of Autonomous Robots Using Bluetooth Communication

Description: This poster discusses research on the cooperation of autonomous robots using Bluetooth communication. Researchers explore multi-agent NXT Robotics systems using a Bluetooth communication channel. This research is part of Research Experiences for Teachers (RET) in Sensor Education, a National Science Foundation (NSF) funded grant project.
Date: 2013
Creator: Freeman, Elizabeth; Bell, Jesse; Namuduri, Kamesh & Costilla, Omar
Partner: UNT College of Engineering

Cooperation of Autonomous NXT Robots Using Bluetooth Wireless Technology

Description: This report discusses research on cooperation of autonomous NXT robots using Bluetooth wireless technology. The research project consisted of using Bluetooth technology to coordinate movements between two agents. This research is part of Research Experiences for Teachers (RET) in Sensor Education, a National Science Foundation (NSF) funded grant project.
Date: 2013
Creator: Bell, Jesse; Freeman, Elizabeth; Namuduri, Kamesh & Costilla, Omar
Partner: UNT College of Engineering