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Surface Remediation in the Aleutian Islands: A Case Study of Amchitka Island, Alaska

Description: Amchitka Island, Alaska, was at one time an integral player in the nation's defense program. Located in the North Pacific Ocean in the Aleutian Island archipelago, the island was intermittently inhabited by several key government agencies, including the U.S. Army, the U.S. Atomic Energy Commission (predecessor agency to the U.S. Department of Energy), and the U.S. Navy. Since 1993, the U.S. Department of Energy (DOE) has conducted extensive investigations on Amchitka to determine the nature and… more
Date: February 25, 2002
Creator: Giblin, M. O.; Stahl, D. C. & Bechtel, J. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling of Neoclassical Tearing Mode Stability for Generalized Toroidal Geometry

Description: Neoclassical tearing modes (NTMs) can lead to disruption and loss of confinement. Previous analysis of these modes used large aspect ratio, low beta (plasma pressure/magnetic pressure) approximations to determine the effect of NTMs on tokamak plasmas. A more accurate tool is needed to predict the onset of these instabilities. As a follow-up to recent theoretical work, a code has been written which computes the tearing mode island growth rate for arbitrary tokamak geometry. It calls PEST-3 [A. P… more
Date: August 21, 2002
Creator: Rosenberg, A. L.; Gates, D. A.; Pletzer, A.; Menard, J. E.; Kruger, S. E.; Hegna, C. C. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanism of Radial Redistribution of Energetic Trapped Ions Due to m=2/n=1 Internal Reconnection in Joint European Torus Shear Optimized Plasmas

Description: Internal radial redistribution of MeV energy ICRF-driven hydrogen minority ions was inferred from neutral particle analyzer measurements during large amplitude MHD activity leading to internal reconnection in Shear Optimized plasmas in the Joint European Torus (JET). A theory is developed for energetic ion redistribution during a reconnection driven by an m=2/n=1 internal kink mode. Plasma motion during reconnection generates an electric field which can change the energy and radial position of … more
Date: January 18, 2002
Creator: Gorelenkov, N. N.; Gondhalekar, A.; Korotkov, A. A.; Sharapov, S. E.; Testa, D. & Workprogramme, and Contributors to the EFDA-JET
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Discharge Improvement Through Control of Neoclassical Tearing Modes by Localized Eccd in Diii-D

Description: A271 DISCHARGE IMPROVEMENT THROUGH CONTROL OF NEOCLASSICAL TEARING MODES BY LOCALIZED ECCD IN DIII-D. Neoclassical tearing modes (NTMs) are MHD modes which can limit the performance of high beta discharges in tokamaks, in some cases leading to a major disruption. The destabilizing effect which results in NTM growth is a helical decrease in the bootstrap current caused by a local reduction of the plasma pressure gradient by seed magnetic islands. The NTM is particularly well suited to control si… more
Date: October 1, 2002
Creator: Prater, R.; Lahaye, R. J.; Lohr, J.; Luce, T. C.; Petty, C. C.; Ferron, J. R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Increased Stable Beta in Diii-D by Suppression of a Neoclassical Tearing Mode Using Electron Cyclotron Current Drive and Active Feedback

Description: OAK A271 INCREASED STABLE BETA IN DIII-D BY SUPPRESSION OF A NEOCLASSICAL TEARING MODE USING ELECTRON CYCLOTRON CURRENT DRIVE AND ACTIVE FEEDBACK. In DIII-D, the first real-time active control of the electron cyclotron current drive stabilization of a neoclassical tearing mode (here m/n=3/2) is demonstrated. The plasma control system is put into a search and suppress mode to align the ECCD with the island by making either small rigid radial position shifts (of order 1 cm) of the entire plasma (… more
Date: September 1, 2002
Creator: Lahaye, R. J.; Humphreys, D. A.; Lohr, J.; Luce, T. C.; Perkins, F. W.; Petty, C. C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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LONG PULSE ADVANCED TOKAMAK DISCHARGES IN THE DIII-D TOKAMAK

Description: One of the main goals for the DIII-D research program is to establish an advanced tokamak plasma with high bootstrap current fraction that can be sustained in-principle steady-state. Substantial progress has been made in several areas during the last year. The resistive wall mode stabilization has been done with spinning plasmas in which the plasma pressure has been extended well above the no-wall beta limit. The 3/2 neoclassical tearing mode has been stabilized by the injection of ECH into the… more
Date: June 1, 2002
Creator: PETERSEN, P.I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Free-boundary Full-pressure Island Healing in a Stellarator: Coil-healing

Description: The lack of axisymmetry in stellarators guarantees that in general magnetic islands and chaotic magnetic field lines will exist. As particle transport is strongly tied to the magnetic field lines, magnetic islands and chaotic field lines result in poor plasma confinement. For stellarators to be feasible candidates for fusion power stations it is essential that, to a good approximation, the magnetic field lines lie on nested flux-surfaces, and the suppression of magnetic islands is a critical is… more
Date: May 7, 2002
Creator: S.R.Hudson; Reiman, A.; Strickler, D.; Brooks, A.; Monticello, D.A. & Hirshman, and S.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Large experiment data analysis collaboration. Final annual progress report for period November 15, 2000 - April 30, 2002

Description: Because of the good agreement between theory and experiment (on a number of tokamak experiments) on the nonlinear development, saturation of neoclassical tearing modes (NTMs), the study of NTMs is becoming a mature subject. Thus, our contributions to studies of neoclassical (and regular classical) tearing modes over the past year have focused on a number of particular, more detailed issues: flow shear effects on linear tearing modes, exploring the possibility of NTMs in spherical tokamaks such … more
Date: January 14, 2002
Creator: Callen, J. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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OBSERVATION OF SUPRATHERMAL ELECTRONS DURING MAGNETIC RECONNECTION AT THE SAWTOOTH INSTABILITY IN DIII-D TOKAMAK

Description: OAK A271 OBSERVATION OF SUPRATHERMAL ELECTRONS DURING MAGNETIC RECONNECTION AT THE SAWTOOTH INSTABILITY IN DIII-D TOKAMAK. Intense bursts of x-ray and electron cyclotron emission are observed during sawtooth instabilities in high-temperature plasmas in the DIII-D tokamak. The bursts are initiated around the X-point of the m = 1, n = 1 magnetic island at the beginning of the sawtooth crash and are displaced to larger radii later during the temperature collapse. Reconstruction of the magnetic con… more
Date: November 1, 2002
Creator: SAVRUKHIN,RV & STRAIT,EJ
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Eliminating Islands in High-pressure Free-boundary Stellarator Magnetohydrodynamic Equilibrium Solutions

Description: Magnetic islands in free-boundary stellarator equilibria are suppressed using a procedure that iterates the plasma equilibrium equations and, at each iteration, adjusts the coil geometry to cancel resonant fields produced by the plasma. The coils are constrained to satisfy certain measures of engineering acceptability and the plasma is constrained to ensure kink stability. As the iterations continue, the coil geometry and the plasma simultaneously converge to an equilibrium in which the island … more
Date: November 19, 2002
Creator: Hudson, S. R.; Monticello, D. A.; Reiman, A. H.; Boozer, A. H.; Strickler, D. J.; Hirshman, S. P. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Annual Program Progress Report under DOE/PHRI Cooperative Agreement: (July 1, 2001-June 30, 2002)

Description: OAK B188 DOE/PHRI Special Medical Care Program in the Republic of the Marshall Islands (RMI)Annual Program Progress Report. The DOE Marshall Islands Medical Program continued, in this it's 48th year, to provide medical surveillance for the exposed population from Rongelap and Utrik and the additional DOE patients. The program was inaugurated in 1954 by the Atomic Energy Commission following the exposure of Marshallese to fallout from a nuclear test (Castle Bravo) at Bikini Atoll. This year mark… more
Date: July 31, 2002
Creator: Palafox, Neal A., MD, MPH
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comprehensive (1986-2001) Characterization of Size at Sexual Maturity for Hawaiian Spiny Lobster (Panulirus marginatus) and Slipper Lobster (Scyllarides squammosus) in the Northwestern Hawaiian Islands

Description: Report on "estimate body size at sexual maturity for Hawaiian spiny lobster and slipper lobster using all available fishery independent research catch data from 1986 to 2001." (pg. 1)
Date: September 2002
Creator: DeMartini, Edward E.; Kleiber, Pierre & DiNardo, Gerard T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Hawaiian Monk Seal in the Northwestern Hawaiian Islands, 2000

Description: The following report produces findings on the field studies over the Hawaiian monk seal in the Northwestern Hawaiian Islands during 2000. The information provided evaluates the status and trends of monk seal subpopulations, natural history traits such as survival, reproduction, growth, behavior, and feeding habits, and the success of various activities designed to facilitate population growth.
Date: August 2002
Creator: Johanos, Thea C. & Baker, Jason D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comprehensive Evaluation of Shallow Reef Fish Populations at French Frigate Shoals and Midway Atoll, Northwestern Hawaiian Islands (1992/93,1995-2000)

Description: From abstract: This document represents the sixth and last of a series of Honolulu Laboratory reports providing estimates of shallow reef fish population densities based on diver-surveys conducted at roughly annual intervals at two sites (French Frigate Shoals (FFS) and Midway Atoll (Midway) in the Northwestern Hawaiian Islands (NWHI)). The purpose of the time series has been to develop the capability to characterize the standing stock densities of shallow reef fishes, as one potentially import… more
Date: December 2002
Creator: DeMartini, Edward E.; Parrish, Frank A. & Boland, Raymond C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of an External Perturbation on a Cylindrical Spheromak

Description: In experiments like the spheromak, it becomes interesting to investigate the quality o f the magnetic flux surfaces in the device. One method of doing so is to impose an external perturbation. If the magnetic field without perturbation is tangled and no flux surfaces exist, then the perturbation will have little effect. However, if the field has well defined flux surfaces, the field should react strongly to a perturbation. Magnetic islands should form and potentially cause a degradation of the … more
Date: May 13, 2002
Creator: Terry, M R
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Science& Technology Review January/February 2003

Description: The topics for this month's issue are: (1) ''Translating Vision into Reality''; (2) ''A Question of Quarks''--Scientists may have created a quark-gluon plasma, a form of matter never before seen on Earth; (3) ''Island Paradise Regained''--Forty-five years after atmospheric nuclear testing ceased, Livermore's environmental scientists continue to develop ways of assessing and limiting radiation exposure associated with resettlement efforts in the Marshall islands; and (4) ''Understanding Cells in… more
Date: December 3, 2002
Creator: Budil, K
Item Type: Refine your search to only Journal/Magazine/Newsletter
Partner: UNT Libraries Government Documents Department
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Individual Radiation: Protection Monitoring in the Marshall Islands: Rongelap Island Resettlement Support (1998-2001)

Description: The United States (U.S.) Department of Energy (DOE) has recently implemented a series of strategic initiatives to address long-term radiological surveillance needs at former U.S. test sites in the Marshall Islands. The plan is to engage local atoll communities in developing shared responsibilities for implementing radiation protection programs for resettled and resettling populations. Using pooled resources of the U.S. Department of Energy and local atoll governments, individual radiation prote… more
Date: May 1, 2002
Creator: Hamilton, Terry; Hickman, David; Conrado, Cynthia; Brown, Thomas; Brunk, James; Marchetti, Alfredo et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Individual Radiation Protection Monitoring in the Marshall Islands: Enewetak Island Resettlement Support (May-December 2001)

Description: The US Department of Energy (DOE) has recently implemented a series of strategic initiatives to address long-term radiological surveillance needs at former US test sites in the Marshall Islands. The plan is to engage local atoll communities in developing shared responsibilities for implementing radiation protection programs for resettled and resettling populations. Using pooled resources of the US Department of Energy and local atoll governments, individual radiation protection programs have be… more
Date: June 1, 2002
Creator: Hamilton, T.; Hickman, D.; Conrado, C.; Brown, T.; Brunk, J.; Marchetti, A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Potassium on Uptake of 137Cs in Food Crops Grown on Coral Soils: Annual Crops at Bikini Atoll

Description: In 1954 a radioactive plume from the thermonuclear device code named BRAVO contaminated the principal residential islands, Eneu and Bikini, of Bikini Atoll (11{sup o} 36 minutes N; 165{sup o} 22 minutes E), now part of the Republic of the Marshall Islands. The resulting soil radioactivity diminished greatly over the three decades before the studies discussed below began. By that time the shorter-lived isotopes had all but disappeared, but strontium-90 ({sup 90}Sr), and cesium-137, ({sup 137}Cs)… more
Date: February 1, 2002
Creator: Stone, E R & Robinson, W
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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EXPLICT CALULATIONS OF HOMOCLINIC TANGLES SURROUNDING MAGNETIC ISLANDS IN TOKAMAKS

Description: We present explicit calculations of the complicated geometric objects known as homoclinic tangles that surround magnetic islands in the Poincare mapping of a tokamak's magnetic field. These tangles are shown to exist generically in the magnetic field of all toroidal confinement systems. The geometry of these tangles provides an explanation for the stochasticity known to occur near the X-points of the Poincare mapping. Furthermore, the intersection of homoclinic tangles from different resonances… more
Date: June 1, 2002
Creator: Roeder, R. K. W.; Rapoport, B. I. & Evans, T. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quarterly Program Progress Report April 1, 2002-June 30, 2002

Description: DOE B188 DOE/PHRI Special Medical Care Program in the Republic of the Marshall Islands (RMI)Quarterly Program Progress Report The DOE/PHRI Special Medical Care Program continues to provide, on a year round basis, a broad spectrum of medical care to the DOE patient population. During the fourth quarter of Year 4, the following medical services were provided: (1) Annual medical examinations for the DOE patient population (see Exhibit 1 for details). (2) Medications for the DOE patient population.… more
Date: July 31, 2002
Creator: Palafox, Neal A., MD, MPH
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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MODELING OF COUPLED EDGE STOCHASTIC AND CORE RESONANT MAGNETIC FIELD EFFECTS IN DIVERTED TOKAMAKS

Description: Attaining the highest performance in poloidally diverted tokamaks requires resonant magnetic perturbation coils to avoid core instabilities (locked, resistive wall and neoclassical tearing modes). These coils also perturb the pedestal and edge region, causing varying degrees of stochasticity with remnant islands. The effects of the DIII-D locked mode control coil on the edge and core of Ohmic plasmas are modeled with the field line integration code TRIP3D and compared with experimental measurem… more
Date: June 1, 2002
Creator: Evans, T. E. & Moyer, R. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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