32 research outputs found
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Los Alamos Plutonium Facility Waste Management System
This paper describes the new computer-based transuranic (TRU) Waste Management System (WMS) being implemented at the Plutonium Facility at Los Alamos National Laboratory (LANL). The Waste Management System is a distributed computer processing system stored in a Sybase database and accessed by a graphical user interface (GUI) written in Omnis7. It resides on the local area network at the Plutonium Facility and is accessible by authorized TRU waste originators, count room personnel, radiation protection technicians (RPTs), quality assurance personnel, and waste management personnel for data input and verification. Future goals include bringing outside groups like the LANL Waste Management Facility on-line to participate in this streamlined system. The WMS is changing the TRU paper trail into a computer trail, saving time and eliminating errors and inconsistencies in the process
Quantum Information Processing with Ferroelectrically Coupled Quantum Dots
I describe a proposal to construct a quantum information processor using
ferroelectrically coupled Ge/Si quantum dots. The spin of single electrons form
the fundamental qubits. Small (<10 nm diameter) Ge quantum dots are optically
excited to create spin polarized electrons in Si. The static polarization of an
epitaxial ferroelectric thin film confines electrons laterally in the
semiconductor; spin interactions between nearest neighbor electrons are
mediated by the nonlinear process of optical rectification. Single qubit
operations are achieved through "g-factor engineering" in the Ge/Si structures;
spin-spin interactions occur through Heisenberg exchange, controlled by
ferroelectric gates. A method for reading out the final state, while required
for quantum computing, is not described; electronic approaches involving single
electron transistors may prove fruitful in satisfying this requirement.Comment: 10 pages, 3 figure
Have I grooved to this before? Discriminating practised and observed actions in a novel context
Learning a new motor skill typically requires converting actions observed from a third-person perspective into fluid motor commands executed from a first-person perspective. In the present study, we test the hypothesis that during motor learning, the ability to discriminate between actions that have been observed and actions that have been executed is associated with learning aptitude, as assessed by a general measure of physical performance. Using a multi-day dance-training paradigm with a group of dance-naïve participants, we investigated whether actions that had been regularly observed could be discriminated from similar actions that had been physically practised over the course of three days, or a further set of similar actions that remained untrained. Training gains and performance scores at test were correlated with participants' ability to discriminate between observed and practised actions, suggesting that an individual's ability to differentiate between visual versus visuomotor action encoding is associated with general motor learning
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OPERATING THE WAND AND HERCULES PROTOTYPE SYSTEMS
Two prototype systems for low-density Green is Clean (GIC) waste at Los Alamos National Laboratory (LANL) have been in operation for three years at the Solid Waste Operation's (SWOs) non-destructive assay (NDA) building. The Waste Assay for Nonradioactive Disposal (WAND) and the High Efficiency Radiation Counters for Ultimate Low Emission Sensitivity (HERCULES) are used to verify the waste generator's acceptable knowledge (AK) that low-density waste is nonradioactive. GIC waste includes all non-regulated waste generated in radiological controlled areas (RCAs) that has been actively segregated as ''clean'' (i.e., nonradioactive) through the use of waste generator AK. GIC waste that is verified clean can be disposed of at the Los Alamos County Landfill. It is estimated that 50-90% of the low-density room trash from RCAs at LANL might be free of contamination. To date, with pilot programs at five facilities at LANL, 3000 cubic feet of GIC waste has been verified clean by these two prototype systems. Both the WAND and HERCULES systems are highly sensitive measurement systems optimized to detect very small quantities of common LANL radionuclides. Both of the systems use a set of phoswich scintillation detectors in close proximity to the waste, which have the capability of detecting plutonium-239 concentrations below 3 pCi per gram of low density waste. Both systems detect low-energy x-rays and a broad range of gamma rays (10-2000 keV), while the WAND system also detects high energy beta particles (>100 keV). The WAND system consists of a bank of six shielded detectors which screen low density shredded waste or stacked sheets of paper moving under the detectors in a twelve inch swath on a conveyor belt. The WAND system was developed and tested at the Los Alamos Plutonium Facility in conjunction with instrument system designers from the Los Alamos Safeguards Science and Technology group. The HERCULES system consists of a bank of three shielded detectors which screen low-density waste in two cubic foot cardboard boxes or in bags sitting on a turntable. Waste that does not pass the verification process can be examined within the facility to determine the type and quantity of the contamination and its origin within a waste container. The paper discusses lessons learned that have helped generators improve their AK segregation
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Los Alamos Plutonium Facility newly generated TRU waste certification
This paper presents an overview of the activities being planned and implemented to certify newly generated contact handled transuranic (TRU) waste produced by Los Alamos National Laboratory`s (LANL`s) Plutonium Facility. Certifying waste at the point of generation is the most important cost and labor saving step in the WIPP certification process. The pedigree of a waste item is best known by the originator of the waste and frees a site from expensive characterization activities such as those associated with legacy waste. Through a cooperative agreement with LANLs Waste Management Facility and under the umbrella of LANLs WIPP-related certification and quality assurance documents, the Plutonium Facility will be certifying its own newly generated waste. Some of the challenges faced by the Plutonium Facility in preparing to certify TRU waste include the modification and addition of procedures to meet WIPP requirements, standardizing packaging for TRU waste, collecting processing documentation from operations which produce TRU waste, and developing ways to modify waste streams which are not certifiable in their present form
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Los Alamos Plutonium Facility newly generated tru waste certification. Final revised version 3/97
This paper presents an overview of the activities being planned and implemented to certify newly generated contact handled transuranic (TRU) waste produced by Los Alamos National Laboratory`s (LANL`s) Plutonium Facility. Certifying waste at the point of generation is the most important cost and labor saving step in the WIPP certification process. The pedigree of a waste item is best known by the originator of the waste and frees a site from many of the expensive characterization activities associated with legacy waste. Through a cooperative agreement with LANLs Waste Management Facility and under the umbrella of LANLs WIPP-related certification and quality assurance documents, the Plutonium Facility will be certifying most of its own newly generated waste. Some of the challenges faced by the Plutonium Facility in preparing to certify TRU waste include the modification and addition of procedures to meet WIPP requirements, standardizing packaging for TRU waste, collecting processing documentation from operations which produce TRU waste, and developing ways to modify waste streams which are not certifiable in their present form
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Documentation of acceptable knowledge for LANL Plutonium Facility transuranic waste streams
Characterization of transuranic waste from the LANL Plutonium Facility for certification and transportation to WIPP includes the use of acceptable knowledge as specified in the WIPP Quality Assurance Program Plan. In accordance with a site-specific procedure, documentation of acceptable knowledge for retrievably stored and currently generated transuranic waste streams is in progress at LANL. A summary overview of the transuranic waste inventory is complete and documented in the Sampling Plan. This document also includes projected waste generation, facility missions, waste generation processes, flow diagrams, times, and material inputs. The second part of acceptable knowledge documentation consists of assembling more detailed acceptable knowledge information into auditable records and is expected to require several years to complete. These records for each waste stream must support final assignment of waste matrix parameters, EPA hazardous waste numbers, and radionuclide characterization. They must also include a determination whether waste streams are defense waste streams for compliance with the WIPP Land Withdrawal Act. The LANL Plutonium Facility`s mission is primarily plutonium processing in basic special nuclear material (SNM) research activities to support national defense and energy programs. It currently has about 100 processes ranging from SNM recovery from residues to development of plutonium 238 heat sources for space applications. Its challenge is to characterize and certify waste streams from such diverse and dynamic operations using acceptable knowledge. This paper reports the progress on the certification of the first of these waste streams to the WIPP WAC
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Systematic evaluation of options to avoid generation of noncertifiable transuranic (TRU) waste at Los Alamos National Laboratory
At present, >35% of the volume of newly generated transuranic (TRU) waste at Los Alamos National Laboratory is not certifiable for transport to the Waste Isolation Pilot Plant (WIPP). Noncertifiable waste would constitute 900--1,000 m{sup 3} of the 2,600 m{sup 3} of waste projected during the period of the Environmental Management (EM) Accelerated Cleanup: Focus on 2006 plan (DOE, 1997). Volume expansion of this waste to meet thermal limits would increase the shipped volume to {approximately}5,400 m{sup 3}. This paper presents the results of efforts to define which TRU waste streams are noncertifiable at Los Alamos, and to prioritize site-specific options to reduce the volume of certifiable waste over the period of the EM Accelerated Cleanup Plan. A team of Los Alamos TRU waste generators and waste managers reviewed historic generation rates and thermal loads and current practices to estimate the projected volume and thermal load of TRU waste streams for Fiscal Years 1999--2006. These data defined four major problem TRU waste streams. Estimates were also made of the volume expansion that would be required to meet the permissible wattages for all waste. The four waste streams defined were: (1) {sup 238}Pu-contaminated combustible waste from production of Radioactive Thermoelectric Generators (RTGs) with {sup 238}Pu activity which exceeds allowable shipping limits by 10--100X. (2) {sup 241}Am-contaminated cement waste from plutonium recovery processes (nitric and hydrochloric acid recovery) are estimated to exceed thermal limits by {approximately}3X. (3) {sup 239}Pu-contaminated combustible waste, mainly organic waste materials contaminated with {sup 239}Pu and {sup 241}Am, is estimated to exceed thermal load requirements by a factor of {approximately}2X. (4) Oversized metal waste objects, (especially gloveboxes), cannot be shipped as is to WIPP because they will not fit in a standard waste box or drum
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Practical Gamma Spectroscopy Assay Techniques for Large Volume Low-Level Waste Boxes
A study was conducted at the Los Alamos National Laboratory (LANL) to evaluate the performance of the SNAP (Spectral Nondestructive Assay Platform) analytical software for measurements of known standards in large metal waste boxes (2.5 m3 volume). The trials were designed to test the accuracy and variance of the analytical results for low-density combustible matrices and higher-density metal matrices at two discrete gamma-ray energies: 121.78 keV and 411.12 keV. For both matrix types the measurement method that produced the most accurate results with the lowest associated standard deviation involved combining four individual measurements taken at the geometric center of each of the box's four vertical sides