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Estimation of doses to individuals from radionuclides disposed of in Solid Waste Storage Area 6 (open access)

Estimation of doses to individuals from radionuclides disposed of in Solid Waste Storage Area 6

A simple methodology has been applied to estimate possible doses to individuals from exposure to radionuclides released from Solid Waste Storage Area No. 6. This is the only operating shallow-land disposal site for radioactive waste at the Oak Ridge National Laboratory. The methodology is based upon simple, conservative, assumptions. A data base of radionuclides disposed of in trenches and auger holes was prepared, and several radionuclide transport and ingestion scenarios were considered. The results of these simulations demonstrate the potential for adverse health effects associated with this waste disposal area, and support the need for further calculations using more complete and realistic assumptions. 5 refs., 6 tabs.
Date: January 1, 1984
Creator: Fields, D.E.; Boegley, W.J. Jr. & Huff, D.D.
System: The UNT Digital Library
Little Boy replication: justification and construction (open access)

Little Boy replication: justification and construction

A reconstruction of the Little Boy weapon allowed experiments to evaluate yield, leakage measurements for comparison with calculations, and phenomenological measurements to evaluate various in-situ dosimeters. The reconstructed weapon was operated at sustained delayed critical at the Los Alamos Critical Assembly Facility. The present experiments provide a wealth of information to benchmark calculations and demonstrate that the 1965 measurements on the Ichiban assembly (a spherical mockup of Little Boy) were in error.
Date: January 1, 1984
Creator: Malenfant, R.E.
System: The UNT Digital Library
EPICS System: System Structure and User Interface (open access)

EPICS System: System Structure and User Interface

This paper present the user's view of and the general organization of the EPICS control system at Fermilab. Various subsystems of the EPICS control system are discussed. These include the user command language, software protection, the device database, remote computer interfaces, and several application utilities. This paper is related to two other papers on EPICS: an overview paper and a detailed implementation paper.
Date: February 1, 1984
Creator: West, R. E.; Bartlett, J. F.; Bobbitt, J. S.; Lahey, T. E.; Kramper, B. J. & MacKinnon, B. A.
System: The UNT Digital Library
Statewide screening for low-level radioactive waste shallow land burial sites (open access)

Statewide screening for low-level radioactive waste shallow land burial sites

A methodology was developed for statewide low-level waste site screening based on NRC site selection criteria. The methodology and criteria were tested in Tennessee to determine their effectiveness in narrowing the choice of sites for more intensive localized site screening. The statewide screening methodology entailed two steps. The first step was to select one or more physiographic provinces wherein sites meeting the criteria were most likely to be found. The second step was to select one or more suitable outcrop bands from within the most favorable physiographic provinces. These selections were based entirely on examination of existing literature and maps at scales no larger than 1:250,000. The statewide screening project identified only one suitable physiographic province (the Mississippi Embayment region) and one favorable outcrop band (the Coon Creek Formation) within a three county area of western Tennessee. Ground water monitoring and predictability proved to be the most difficult criterion to meet. This criterion alone eliminated other outcrop bands in the Mississippi Embayment as well as the Eastern Highland Rim and Western Highland Rim physiographic provinces. Other provinces failed to meet several screening criteria. 3 references, 3 figures, 1 table.
Date: January 1, 1984
Creator: Staub, W.P.; Cannon, J.B. & Stratton, L.E.
System: The UNT Digital Library
Relativistic fluid formulation and theory of intense relativistic electron beams (open access)

Relativistic fluid formulation and theory of intense relativistic electron beams

A new general relativistic fluid formulation has been obtained for intense relativistic electron beams (IREB) with arbitrarily high relativistic mass factor ..gamma... This theory is valid for confined IREB equilibria such as those found inside high energy accelerators as well as in the pinched and ion-focused regimes of beam propagation in plasma channels. The new relativistic fluid formulation is based on the covariant relativistic fluid formulation of Newcomb with the parameter lambda identical to 1, in order to allow for realistic confined equilibria. The resulting equilibrium constraints require that the beam has a slow rotational velocity around its direction of propagation and that the off-diagonal thermal stress element, associated with these two directions of motion, be nonzero. The effective betatron oscillation frequency of the fluid elements of the beam is modified by the radial gradient and anisotropies in the thermal stress elements of the beam fluid. The wave equation, for sausage, hose and filamentation excitations on the relativistic fluid beam, is found to be formally identical to that obtained from the Vlasov equation approach, hence phase-mixing damping is a generic and self-consistent correlate of the new relativistic fluid formulation.
Date: January 1, 1984
Creator: Siambis, J.G.
System: The UNT Digital Library
Overall plant concept for a tank-type fast reactor (open access)

Overall plant concept for a tank-type fast reactor

Japanese nuclear industries are expressing interest in the merits of the tank-type FBR as a large plant (demonstration) after JOYO (experimental, in operation) and MONJU (prototype, under construction). In response to this growing interest in a tank-type FBR demonstration plant, Hitachi has initiated a conceptual study of a 1000 MWe tank plant concept in collaboration with GE and Bechtel. Key objectives of this study have been: to select reliable and competitive tank plant concepts, with emphases on a seismic-resistant and compact tank reactor system;to select reliable shutdown heat removal system;and to identify R and D items needed for early 1990s construction. Design goals were defined as follows: capital costs must be less than twice, and as close as practical to 1.5 those of equivalent LWR plants;earthquake resistant structures to meet stringent Japanese seismic conditions must be as simple and reliable as practical;safety must be maintained at LWR-equivalent risks;and R and D needs must be limited to minimum cost for the limited time allowed. This paper summarizes the overall plant concepts with some selected topics, whereas detailed descriptions of the reactor assembly and the layout design are found in separate papers.
Date: January 1, 1984
Creator: Yamaki, Hideo; Davies, S.M. & Goodman, L.
System: The UNT Digital Library
Attacks on computers: Congressional hearings and pending legislation (open access)

Attacks on computers: Congressional hearings and pending legislation

During the First Session of the 98th Congress, several days of hearings were held on the activities of computer enthusiasts including the Milwaukee 414s and others. The First Session also saw the introduction in the House of six bills dealing with various aspects and computer crime. A summary of those hearings, along with a summary of the pending computer crime bills, will be presented.
Date: January 1, 1984
Creator: Bailey, D.
System: The UNT Digital Library
Environmental surveillance for low-level waste disposal sites. [Shallow-land burial] (open access)

Environmental surveillance for low-level waste disposal sites. [Shallow-land burial]

All nuclear facilities, including waste disposal sites, are expected to evaluate their effect on the environment. This paper describes a multidisciplinary approach to the design of environmental surveillance programs for near-surface disposal sites. Surveillance is broadly considered to include burial trench and other on-site measurements as well as offsite monitoring, and to include both radiological and non-radiological measurements. The objectives of a surveillance program are: to determine the extent of any pollutant migration early enough for corrective action to be taken to minimize adverse impacts, to provide data to assess the impact of site operations on the environment and public, to predict long-term waste behavior, to satisfy regulatory agency requirements, and to obtain data on site and pollutant behavior for the design of future disposal sites and surveillance programs. It should be recognized that shallow-land burial techniques will not retain the waste completely in place over time. Some migration is expected, but it must be acceptable in amount and rate. Surveillance programs will provide the information to determine if this is the case. Proper application of monitoring techniques and principles will result in a program that will meet its objectives and supply the data needed by operators and regulators to …
Date: January 1, 1984
Creator: Sedlet, J.
System: The UNT Digital Library
FOODCHAIN: a Monte Carlo model to estimate individual exposure to airborne pollutants via the foodchain pathway (open access)

FOODCHAIN: a Monte Carlo model to estimate individual exposure to airborne pollutants via the foodchain pathway

Ingestion of contaminated food due to the airborne release of radionuclides or chemical pollutants is a particularly difficult human exposure pathway to quantify. There are a number of important physical and biological processes such as atmospheric deposition and plant uptake to consider. These processes are approximate by techniques encoded in the computer program TEREX. Once estimates of pollutant concentrations are made, the problem can be reduced to computing exposure from ingestion of the food. Some assessments do not account for where the contaminated food is eaten, while others limit consumption to meat and vegetables produced within the affected area. While those approaches lead to an upper bound of exposure, a more realistic assumption is that if locally produced food is not sufficient to meet the dietary needs of the local populace, then uncontaminated food will be imported. This is the approach taken by the computer model FOODCHAIN. Exposures via ingestion of six basic types of food are modeled: beef, milk, grains, leafy vegetables, exposed produce (edible parts are exposed to atmospheric deposition), and protected produce (edible parts are protected from atmospheric deposition). Intake requirements for these six foods are based on a standard diet. Using TEREX-produced site-specific crop production values …
Date: January 1, 1984
Creator: Dixon, E. & Holton, G.A.
System: The UNT Digital Library
Large area spark counter with fine time and position resolution (open access)

Large area spark counter with fine time and position resolution

The key properties of spark counters include their capability of precision timing (at the sub 100 ps level) and of measuring the position of the charged particle to high accuracy. At SLAC we have undertaken a program to develop these devices for use in high energy physics experiments involving large detectors. A spark counter of size 1.2 m x 0.1 m has been constructed and has been operating continuously in our test setup for several months. Some details of its construction and its properties as a particle detector are reported. 14 references. (WHK)
Date: March 1, 1984
Creator: Ogawa, A.; Fujiwara, N.; Pestov, Yu.N. & Sugahara, R.
System: The UNT Digital Library
ECRH and ICRH in the TMX-U Tandem Mirror (open access)

ECRH and ICRH in the TMX-U Tandem Mirror

In the Tandem Mirror Experiment Upgrade (TMX-U), the formation of a thermal barrier and the potential plugging of ion end loss were achieved at central-cell densities up to 2 x 10/sup 12/ cm/sup -3/. The presence of a thermal barrier was confirmed by direct measurement, and ion axial-confinement times in the range 50 to 100 ms were measured. The ECRH in the end cells (a) initiates plasma startup, (b) generates hot, mirror-confined electrons to form thermal barriers, and (c) creates the plugging potential for central-cell ions. The ECRH system consists of four 200 kW, 28 GHz gyrotrons each feeding power to a separate heating location (two in each end plug). Fundamental heating is used at the potential plug, and second harmonic is used in the thermal barrier. Hot-electron plasmas are produced at total end-cell antenna power levels up to 300 kW. Strong single-pass absorption and net hot-electron heating efficiencies exceeding 40% are observed. Hot-electron parameters achieved are: n/sub eh//n/sub et/ up to 0.8, volume-average beta <..beta..> approx. = 0.15, and T/sub x/ (x-ray tail above 40 keV) in the range 75 to 200 keV.
Date: March 15, 1984
Creator: Stallard, B. W.; Cummins, W. F.; Molvik, A. W.; Poulsen, P.; Simonen, T. C.; Falabella, S. et al.
System: The UNT Digital Library
XIX Recontre de Moriond. Summary talk (open access)

XIX Recontre de Moriond. Summary talk

The theoretical arguments for neutrino mass are reviewed, and the present status of searches for neutrino mass in neutrino oscillations, direct measurements and other experiments are summarized. 46 references.
Date: January 1, 1984
Creator: Rosen, S.P.
System: The UNT Digital Library
Results from simulated upper-plenum aerosol transport and aerosol resuspension experiments (open access)

Results from simulated upper-plenum aerosol transport and aerosol resuspension experiments

Recent calculational results published as part of the Battelle-Columbus BMI-2104 source term study indicate that, for some LWR accident sequences, aerosol deposition in the reactor primary coolant system (PCS) can lead to significant reductions in the radionuclide source term. Aerosol transport and deposition in the PCS have been calculated in this study using the TRAP-MELT 2 computer code, which was developed at Battelle-Columbus; the status of validation of the TRAP-MELT 2 code has been described in an Oak Ridge National Laboratory (ORNL) report. The objective of the ORNL TRAP-MELT Validation Project, which is sponsored by the Fuel Systems Behavior Research Branch of the US Nuclear Regulatory Commission, is to conduct simulated reactor-vessel upper-plenum aerosol deposition and transport tests. The results from these tests will be used in the ongoing effort to validate TRAP-MELT 2. The TRAP-MELT Validation Project includes two experimental subtasks. In the Aerosol Transport Tests, aerosol transport in a vertical pipe is being studied; this geometry was chosen to simulate aerosol deposition and transport in the reactor-vessel upper-plenum. To date, four experiments have been performed; the results from these tests are presented in this paper. 7 refs., 4 figs., 4 tabs.
Date: January 1, 1984
Creator: Wright, A.L. & Pattison, W.L.
System: The UNT Digital Library
Mapping liquid hazardous waste migration in ground water with electromagnetic terrain conductivity measurement (open access)

Mapping liquid hazardous waste migration in ground water with electromagnetic terrain conductivity measurement

Electromagnetic conductivity measurements were used to map apparent ground conductivity in the vicinity of a liquid hazardous waste disposal site. Approximately 600 conductivity measurements were obtained to prepare a conductivity map of the site which includes an area of 12 ha (30 acres). Conductivity measurements in the area correlate with specific conductance measurements of surface and ground water samples. Contouring of the conductivity data located contaminant migration pathways in the subsurface. A complex contaminant plume was defined by the conductivity survey. Conductivity values obtained reflected anisotropic characteristics related to local bedrock structure. Anisotropic characteristics of measurements and the use of different instrument configurations indicated semiquantitatively the depth of the high conductivity zone and the direction of flow. 4 references, 2 figures.
Date: January 1, 1984
Creator: Ketelle, R.H. & Pin, F.G.
System: The UNT Digital Library
Energy response and dose-rate calibration of a Geiger-Mueller gamma-ray detector (open access)

Energy response and dose-rate calibration of a Geiger-Mueller gamma-ray detector

To obtain more precise dose-rate measurements, we have taken a commercial gamma-ray dosimeter that uses a Geiger-Mueller (GM) tube as its detector and, by supplying it with an externally regulated high voltage, counted the gamma-ray-induced pulses with suitable scaling and timing circuits. We have now improved the method of calibration by measuring detector response to 13 different sources, each with an independently verified strength, in the energy range from 60 keV to 2.6 MeV. With the use of computer codes, the resulting response curve can be folded into the spectrum of the source to be measured.
Date: January 1, 1984
Creator: Plassmann, E.A.; Pederson, R.A. & Moss, C.E.
System: The UNT Digital Library
Distributed Microprocessor Automation Network for Synthesizing Radiotracers Used in Positron Emission Tomography (open access)

Distributed Microprocessor Automation Network for Synthesizing Radiotracers Used in Positron Emission Tomography

This presentation describes an evolving distributed microprocessor network for automating the routine production synthesis of radiotracers used in Positron Emission Tomography. We first present a brief overview of the PET method for measuring biological function, and then outline the general procedure for producing a radiotracer. The paper identifies several reasons for our automating the syntheses of these compounds. There is a description of the distributed microprocessor network architecture chosen and the rationale for that choice. Finally, we speculate about how this network may be exploited to extend the power of the PET method from the large university or National Laboratory to the biomedical research and clinical community at large. 20 refs. (DT)
Date: September 1, 1984
Creator: Russell, J. A. G.; Alexoff, D. L. & Wolf, A. P.
System: The UNT Digital Library
Measurement of electromagnetic shower position and size with a saturated avalanche tube hodoscope and a fine grained scintillation hodoscope (open access)

Measurement of electromagnetic shower position and size with a saturated avalanche tube hodoscope and a fine grained scintillation hodoscope

A hodoscope has been constructed from 100 ..mu.. m diameter wires and brass tubes (1.2 x 0.7 cm/sup 2/ cross section) filled with a mixture of argon, ethane and ethyl alcohol. It has been tested in the saturated avalanche mode in an SCG1-C electromagnetic shower detector to determine its properties for the measurement of the position and size of electromagnetic showers. Two of these tube hodoscopes were positioned 3.5 radiation lengths deep in the detector and the profiles of 1 to 25 GeV electromagnetic showers were measured. Simultaneous measurements were performed using a plane of twenty, 0.5 cm wide scintillation counters positioned immediately behind the gas tube hodoscope. In addition the transition between saturated avalanche and limited streamer modes has been measured for the tube hodoscopes.
Date: January 1, 1984
Creator: Rameika, R.; Cox, B.; Jenkins, C. M.; Judd, D. J.; Hale, G.; Mazur, P. O. et al.
System: The UNT Digital Library
Interactions of fast atomic and molecular ions with matter (open access)

Interactions of fast atomic and molecular ions with matter

Brief discussions are presented of research performed in the following areas: microwave field ionization of fast Rydberg atoms; electric field ionization of foil-excited Rydberg states of fast heavy ions; post-foil interaction in foil-induced molecular dissociation; and angular distributions of foil-excited ions bearing inner shell vacancies. 19 references. (GHT)
Date: January 1, 1984
Creator: Kanter, E. P.; Gemmell, D. S. & Vager, Z.
System: The UNT Digital Library
Principles and prospects for micro heat pipes (open access)

Principles and prospects for micro heat pipes

The fabrication and purpose of very small wickless heat pipes are discussed. A theoretical analysis of their performance characteristics shows that they have nearly the heat transport capability expected by scaling down from conventional heat pipes. They appear attractive for applications calling for close temperature control, but having only modest cooling requirements.
Date: January 1, 1984
Creator: Cotter, T. P.
System: The UNT Digital Library
Effect of resonant microwave power on a PIG ion source. Revision (open access)

Effect of resonant microwave power on a PIG ion source. Revision

We have investigated the effect of applying microwave power at the electron cyclotron frequency on the characteristics of the ion beam extracted from a hot-cathode PIG ion source. No change was seen in the ion charge state distribution. A small but significant reduction in the beam noise level was seen, and it is possible that the technique may find application in situations where beam quiescence is important. 32 refs., 2 figs.
Date: August 1, 1984
Creator: Brown, I.G.; Galvin, J.E.; Gavin, B.F. & MacGill, R.A.
System: The UNT Digital Library
Reliability analysis using network simulation (open access)

Reliability analysis using network simulation

A computer code that uses a dynamic, Monte Carlo modeling approach is Q-GERT (Graphical Evaluation and Review Technique--with Queueing), and the present study has demonstrated the feasibility of using Q-GERT for modeling time-dependent, unconditionally and conditionally linked phenomena that are characterized by arbitrarily selected probability distributions.
Date: January 1, 1984
Creator: unknown
System: The UNT Digital Library
Field generated within the SSC magnets due to persistant currents in the superconductor (open access)

Field generated within the SSC magnets due to persistant currents in the superconductor

This report presents the results of a number of computer studies of the magnetic fields generated by persistent circulating currents in the superconductor of superconducting dipoles. These magnetic fields are referred to as residual fields throughout this report. Since the field generated by persistent currents have a hysteric behavior, they are analagous to the residual filed found in iron bound conventional solenoids. The residual field calculations presented in this report were done using the LBL SCMAG4 computer code. This code has not been well tested against measured data, but a comparison with measured CBA data given in this report suggests that good agreement is possible. The residual fields generated by persistent superconducting currents are rich in higher multipoles. This is of concern to the accelerator designer for SSC. This report shows the effect of various superconductor parameters and coil parameters on the magnitude and structure of the residual fields. The effect of the magnet charging history on residual fields is aldo discussed. 14 references.
Date: January 1, 1984
Creator: Green, Michael A.
System: The UNT Digital Library
Smart instrumentation development at Los Alamos (open access)

Smart instrumentation development at Los Alamos

For several years Los Alamos has incorporated microprocessors into instruments to expand the capability of portable survey type equipment. Beginning with portable pulse height analyzers, the developments have expanded to small dedicated instruments which handle the measurement and interpretation of various radiation fields. So far, instruments to measure gamma rays, neutrons, and beta particles have been produced. The computer capability built into these instruments provides significant computational power into the instruments. Capability unheard of a few years ago in small portable instruments is routine today. Large computer-based laboratory measurement systems which required much space and electrical power can now be incorporated in a portable hand-held instrument. The microprocessor developments at Los Alamos are now restricted to radiation monitoring equipment but can be expanded to chemical and biological applications as well. Applications for radiation monitoring equipment and others are discussed.
Date: January 1, 1984
Creator: Erkkila, B.
System: The UNT Digital Library
Neutron dosimetry of the Little Boy device (open access)

Neutron dosimetry of the Little Boy device

Neutron dose rates at several angular locations and at distances out to 0.5 mile have been measured during critical operation of the Little Boy replica. We used modified remmetes and thermoluminescent dosimetry techniques for the measurements. The present status of our analysis is presented including estimates of the neutron-dose-relaxation length in air and the variation of the neutron-to-gamma-ray dose ratio with distance from the replica. These results are preliminary and are subject to detector calibration measurements.
Date: January 1, 1984
Creator: Pederson, R.A. & Plassmann, E.A.
System: The UNT Digital Library