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User's guide for GAPCON-THERMAL-2: A computer program for calculating the thermal behavior of an oxide fuel rod
This report is being published as a user's manual for GAPCON-THERMAL-2 and provides a general description of the code and instructions for its use. The GAPCON-THERMAL-2 code was developed for the Regulatory Staff, NRC, to use as a tool in estimating fuel-cladding gap conductances and fuel stored energy and represents a modification of the GAPCON-THERMAL-1 code. The goal of the modifications was to reduce uncertainties associated with calculating power history and burnup effects and yet retain a relatively flexible and fast running code for parametric studies. 15 references (auth
Design innovation for the 1990's
Statement of responsibility on title-page reads: Richard K. Lester, Michael J. Driscoll, Michael W. Golay, David D. Lanning, Lawrence M. Lidsky, Norman C. Rasmussen and Neil E. Todreas"September 1983."Includes bibliographical reference
Precharacterization Report for Instrumented Fuel Assembly (IFA)-527
This report is a resource document covering the rationale, design, fabrication, and preirradiation characterization of instrumented fuel assembly (IFA)-527. This assembly is being irradiated in the Halden Boiling Water Reactor (HBWR) in Norway as part of the Experimental Support and Development of Single-Rod Fuel Codes Program conducted by Pacific Northwest laboratory (PNL) and sponsored by the Fuel Behavior Research Branch of the U.S. Nuclear Regulatory Commission (NRC). Data from this assembly will be used to better understand light water reactor (LWR) fuel behavior under normal operating conditions
Two-Way Quantum Time Transfer: A Method for Daytime Space-Earth Links
Remote clock synchronization is crucial for many classical and quantum
network applications. Current state-of-the-art remote clock synchronization
techniques achieve femtosecond-scale clock stability utilizing frequency combs,
which are supplementary to quantum-networking hardware. Demonstrating an
alternative, we synchronize two remote clocks across our freespace testbed
using a method called two-way quantum time transfer (QTT). In one second we
reach picosecond-scale timing precision under very lossy and noisy channel
conditions representative of daytime space-Earth links with commercial
off-the-shelf quantum-photon sources and detection equipment. This work
demonstrates how QTT is potentially relevant for daytime space-Earth quantum
networking and/or providing high-precision secure timing in GPS-denied
environments.Comment: arXiv admin note: text overlap with arXiv:2211.0073
Optimal static pricing for a tree network
We study the static pricing problem for a network service provider in a loss system with a tree structure. In the network, multiple classes share a common inbound link and then have dedicated outbound links. The motivation is from a company that sells phone cards and needs to price calls to different destinations. We characterize the optimal static prices in order to maximize the steady-state revenue. We report new structural findings as well as alternative proofs for some known results. We compare the optimal static prices versus prices that are asymptotically optimal, and through a set of illustrative numerical examples we show that in certain cases the loss in revenue can be significant. Finally, we show that static prices obtained using the reduced load approximation of the blocking probabilities can be easily obtained and have near-optimal performance, which makes them more attractive for applications.Massachusetts Institute of Technology. Center for Digital BusinessUnited States. Office of Naval Research (Contract N00014-95-1-0232)United States. Office of Naval Research (Contract N00014-01-1-0146)National Science Foundation (U.S.) (Contract DMI-9732795)National Science Foundation (U.S.) (Contract DMI-0085683)National Science Foundation (U.S.) (Contract DMI-0245352
Reactor physics project final report
"September 30, 1970."Statement of responsibility on title-page reads: Editors, M. J. Driscoll, I. Kaplan, D. D. Lanning, N. C. Rasmussen. Contributors: V. K. Agarwala, F. M. Clikeman, M. J. Driscoll, Y. Hukai, L. L. Izzo, I. Kaplan, M. S. Kazimi, D.D. Lanning, T.C. Leung, E.L. McFarland, N.C. Rasmussen, S.S. Seth, G.E. Sullivan, and A.T. SuppleIncludes bibliographical referencesFinal report; January 1, 1968 to September 30, 1970This is the final report in an experimental and theoretical program to develop and apply single- and few-element methods for the determination of reactor lattice parameters. The period covered by the report is January 1, 1968 through September 30, 1970. In addition to summarizing results for the entire contract period, this report also serves as the final annual report; thus, work completed in the period of October 1, 1969 through September 30, 1970 is dealt with in more detail than the earlier work. Methods were developed to measure the heterogeneous parameters 17, [Gamma] [eta] and [Alpha] for single fuel elements immersed in moderator in an exponential tank using foil activation measurements external to the fuel. These methods were applied to clustered fuel rods in D 20 moderator and single fuel rods in H 20 moderator, and the results were extended to and compared with data on complete multi-element lattices reported by other laboratories. Advanced gamma spectrometric methods using Ge(Li) detectors were applied to the analysis of both prompt and fission product decay gammas for the nondestructive analysis of the fuel used in this work. The latter includes both simulated burned fuel containing plutonium and actual burned fuel irradiated to 20,000 MWD/T in the Dresden BWR.U.S. Atomic Energy Commission contract AT (30-1)-394
The Small GTPase RhoA Localizes to the Nucleus and Is Activated by Net1 and DNA Damage Signals
Rho GTPases control many cellular processes, including cell survival, gene expression and migration. Rho proteins reside mainly in the cytosol and are targeted to the plasma membrane (PM) upon specific activation by guanine nucleotide exchange factors (GEFs). Accordingly, most GEFs are also cytosolic or associated with the PM. However, Net1, a RhoA-specific GEF predominantly localizes to the cell nucleus at steady-state. Nuclear localization for Net1 has been seen as a mechanism for sequestering the GEF away from RhoA, effectively rendering the protein inactive. However, considering the prominence of nuclear Net1 and the fact that a biological stimulus that promotes Net1 translocation out the nucleus to the cytosol has yet to be discovered, we hypothesized that Net1 might have a previously unidentified function in the nucleus of cells.Using an affinity precipitation method to pulldown the active form of Rho GEFs from different cellular fractions, we show here that nuclear Net1 does in fact exist in an active form, contrary to previous expectations. We further demonstrate that a fraction of RhoA resides in the nucleus, and can also be found in a GTP-bound active form and that Net1 plays a role in the activation of nuclear RhoA. In addition, we show that ionizing radiation (IR) specifically promotes the activation of the nuclear pool of RhoA in a Net1-dependent manner, while the cytoplasmic activity remains unchanged. Surprisingly, irradiating isolated nuclei alone also increases nuclear RhoA activity via Net1, suggesting that all the signals required for IR-induced nuclear RhoA signaling are contained within the nucleus.These results demonstrate the existence of a functional Net1/RhoA signaling pathway within the nucleus of the cell and implicate them in the DNA damage response
Scattered-Light Echoes from the Historical Galactic Supernovae Cassiopeia A and Tycho (SN 1572)
We report the discovery of an extensive system of scattered light echo
arclets associated with the recent supernovae in the local neighbourhood of the
Milky Way: Tycho (SN 1572) and Cassiopeia A. Existing work suggests that the
Tycho SN was a thermonuclear explosion while the Cas A supernova was a core
collapse explosion. Precise classifications according to modern nomenclature
require spectra of the outburst light. In the case of ancient SNe, this can
only be done with spectroscopy of their light echo, where the discovery of the
light echoes from the outburst light is the first step. Adjacent light echo
positions suggest that Cas A and Tycho may share common scattering dust
structures. If so, it is possible to measure precise distances between
historical Galactic supernovae. On-going surveys that alert on the development
of bright scattered-light echo features have the potential to reveal detailed
spectroscopic information for many recent Galactic supernovae, both directly
visible and obscured by dust in the Galactic plane.Comment: 4 pages, 4 color figures, accepted for publication in ApJ
Progress report no. 2
Statement of responsibility on title-page reads: Editors: I.A. Forbes, M.J. Driscoll, N.C. Rasmussen, D.D. Lanning and I. Kaplan; Contributors: S.T. Brewer, G.J. Brown, P.DeLaquil, III, M.J. Driscoll, I.A. Forbes, C.W. Forsberg, E.P. Gyftopoulos, P.L. Hendrick, C.S. Kang, I. Kaplan, J.L. Klucar, D.D. Lanning, T.C. Leung, E.A. Mason, N.R. Ortiz, N.A. Passman, N.C. Rasmussen, I.C. Rickard, V.C. Rogers, G.E. Sullivan, A.T. Supple, and C. P. TzanosIncludes bibliographical referencesProgress report; June 30, 1971U.S. Atomic Energy Commission contract AT(11-1)306
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