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At least 559 records · Page 31

2019 Integrated facilities and infrastructure plan

This document, the Sandia National Laboratories lntegrated Facilities and lnfrastructure Plan, summarizes long-, mid-, and short-term site planning to support Sandia's mission. High-level direction that influences site development includes the Stockpile Stewardship and Management Plan (SSMP) and Nuclear Posture Review (NPR), while the relationship to National Nuclear Security Administration (NNSA) infrastructure is described in the NNSA Master Asset Plan (MAP). Using the SSMP as an indication of the future workload informs the planning process for facilities and infrastructure. Figure 1 shows the outlook of the NNSAs nuclear weapons modernization programs through the year 2042, which indicates a stable, slightly growing workload.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

NASA Tech Briefs, February 2009

Tech Briefs are short announcements of innovations originating from research and development activities of the National Aeronautics and Space Administration. They emphasize information considered likely to be transferable across industrial, regional, or disciplinary lines and are issued to encourage commercial application. Topics covered include: Measuring Low Concentrations of Liquid Water in Soil; The Mars Science Laboratory Touchdown Test Facility; Non-Contact Measurement of Density and Thickness Variation in Dielectric Materials; Compact Microwave Fourier Spectrum Analyzer; InP Heterojunction Bipolar Transistor Amplifiers to 255 GHz; Combinatorial Generation of Test Suites; In-Phase Power-Combined Frequency Tripler at 300 GHz; Electronic System for Preventing Airport Runway Incursions; Smaller but Fully Functional Backshell for Cable Connector; Glove-Box or Desktop Virtual-Reality System; Composite Layer Manufacturing with Fewer Interruptions; Improved Photoresist Coating for Making CNT Field Emitters; A Simplified Diagnostic Method for Elastomer Bond Durability; Complex Multifunctional Polymer/Carbon-Nanotube Composites; Very High Output Thermoelectric Devices Based on ITO Nanocomposites; Reducing Unsteady Loads on a Piggyback Miniature Submarine; Ultrasonic/Sonic Anchor; Grooved Fuel Rings for Nuclear Thermal Rocket Engines; Pulsed Operation of an Ion Accelerator; Autonomous Instrument Placement for Mars Exploration Rovers; Mission and Assets Database; TCP/IP Interface for the Satellite Orbit Analysis Program (SOAP); Trajectory Calculator for Finite-Radius Cutter on a Lathe; Integrated System Health Management Development Toolkit.

Source record↗

PHM Enabled Autonomous Propellant Loading Operations

The utility of Prognostics and Health Management (PHM) software capability applied to Autonomous Operations (AO) remains an active research area within aerospace applications. The ability to gain insight into which assets and subsystems are functioning properly, along with the derivation of confident predictions concerning future ability, reliability, and availability, are important enablers for making sound mission planning decisions. When coupled with software that fully supports mission planning and execution, an integrated solution can be developed that leverages state assessment and estimation for the purposes of delivering autonomous operations. The authors have been applying this integrated, model-based approach to the autonomous loading of cryogenic spacecraft propellants at Kennedy Space Center.

Walker, Mark↗

Autonomic Management of Space Missions

With NASA s renewed commitment to outer space exploration, greater emphasis is being placed on both human and robotic exploration. Even when humans are involved in the exploration, human tending of assets becomes cost-prohibitive or in many cases is simply not feasible. In addition, certain exploration missions will require spacecraft that will be capable of venturing where humans cannot be sent. Early space missions were operated manually from ground control centers with little or no automated operations. In the mid-l980s, the high costs of satellite operations prompted NASA, and others, to begin automating as many functions as possible. In our context, a system is autonomous if it can achieve its goals without human intervention. A number of more-or-less automated ground systems exist today, but work continues with the goal being to reduce operations costs to even lower levels. Cost reductions can be achieved in a number of areas. Ground control and spacecraft operations are two such areas where greater autonomy can reduce costs. As a consequence, autonomy is increasingly seen as a critical approach for robotic missions and for some aspects of manned missions. Although autonomy will be critical for the success of future missions (and indeed will enable certain kinds of science data gathering approaches), missions imbued with autonomy must also exhibit autonomic properties. Exploitation of autonomy alone, without emphasis on autonomic properties, will leave spacecraft vulnerable to the dangerous environments in which they must operate. Without autonomic properties, a spacecraft may be unable to recognize negative environmental effects on its components and subsystems, or may be unable to take any action to ameliorate the effects. The spacecraft, though operating autonomously, may then sustain a degradation of performance of components or subsystems, and consequently may have a reduced potential for achieving mission objectives. In extreme cases, lack of autonomic properties could leave the spacecraft unable to recover from faults. Ensuring that exploration spacecraft have autonomic properties will increase the survivability and therefore the likelihood of success of these missions. In fact, over time, as mission requirements increased demands on spacecraft capabilities and longevity, designers have gradually built more autonomicity into spacecraft. For example, a spacecraft in low-earth orbit may experience an out-of-bounds perturbation of its attitude (orientation) due to increased drag caused by increased atmospheric density at its altitude as a result of a sufficiently large solar flare. If the spacecraft was designed to recognize the excessive attitude perturbation, it could decide to protect itself by going into a safe-hold mode where its internal configuration and operation are altered to conserve power and its coarse attitude is adjusted to point its solar panels toward the Sun to maximize power generation. This is an example of a simple type of autonomic behavior that has actually occurred. Future mission concepts will be increasingly dependent on space system survivability enabled by more advanced types of autonomic behaviors

Hinchey, Michael G.↗

Sustainable Transactions - The Fine Art of the Forever Deal - 19569

The U.S. Department of Energy Office of Legacy Management (LM) has various real property interests at the 92 sites within its current portfolio. Because of its unique mission, LM does not own most of the sites for which it has responsibility for long-term surveillance and maintenance (LTS and M). In addition to the sites it does own, LM works with various federal, state, local, and private entities to execute its obligations. Each site has its own narrative with respect to the real property assets: how they were acquired, how they are sustained, and how they were or will be dispositioned. Since the regulatory time frame for LTS and M activities at some sites can be in perpetuity, durable and effective instruments and documentation are necessary to support LM's mission as a federal land manager and steward. In addition, more than half of the sites currently in LM's inventory do not allow unrestricted use because of residual contamination from historical activities, and institutional controls are required to limit human and environmental exposures to residual contamination by controlling land use, restricting access to potential hazards, and making the public aware of potential dangers from the residual contamination. Thus, the overall real property interests and transactions associated with these sites not only have to address the environmental concerns associated with protection of human health and the environment but also how best to position LM's real property assets to support the mission for future generations. These types of transactions are often complex, requiring the negotiation of numerous documents to achieve and sustain protection of human health and the environment while allowing for future use. Such planning needs to be flexible enough to envision that the original transaction will likely change over time due to changing regulations, communities, stakeholders, and site conditions as operation and maintenance activities are performed. Planning for the integration of these requirements with the needs of the end users, stakeholders, and communities is paramount to a successful project, and various transactional considerations impact how best to achieve this goal. As such, these transactions have to be sustainable. Real property interests change over time, with new owners, operators, regulators, and stakeholders. Determining the sustainability of these real property interests, therefore, calculates the sustainability of each asset's physical attributes and also the sustainability of the various legal instruments and arrangements that are put in place at each site. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

High-Power Electric Vehicle Charging Hub Integration Platform (eCHIP): Site Energy Management System Platform Development

A site energy management system is a critical component of future high-power EV charging hubs. It monitors and supervises all inter-hub operations, coordinates grid interactions, and implements energy management strategies and load-sharing controls at various levels and time scales. This report provides a comprehensive high-level overview and guidelines on the essential elements of such energy management systems. These elements primarily focus on the core functions, architecture, and monitoring aspects of site energy management. The core functions define the grid services and operational objectives that a charging hub is expected to provide and achieve. The architectural section investigates the coordination between hub assets, different control schemes, and their potential benefits and drawbacks. Lastly, the report discusses the needs, types, and functionalities of a monitoring and visualization system.

24 POWER TRANSMISSION AND DISTRIBUTION↗

IDN Update

To present on recent developments of the IDN including the migration of Earth Dataset collection and services to the Common Metadata Repository (CMR), development of dMMT and IDN Search Portal. Discuss working with the other CEOS agencies to get agreements to make decisions on future interoperability approaches for IDN and for the WGISS Connected Assets systems approaches for IDN and for the WGISS Connected Assets systems.

Committee on Earth Observation Satellites (CEOS)↗

Panel Session 133: Integrating Economic Redevelopment and Workforce Transition Into DOE Site Closure Planning (R1.18)

This panel focused on post-closure impacts to the long-term site workforce and communities in DoE's approach to accelerated site cleanup and expedited reduction of long-term financial liabilities. At sites where Cold-War workers shifted from weapons production to the cleanup effort, a more holistic approach to the workforce transition Post-EM cleanup is needed. This holistic approach would include incentives for expedited closure, trade re-training, and a vision for future site commercial activities. The panel discussed the importance of the right workforce incentives that includes appropriate training for displaced workers so that they can be integrated into a next job. A key aspect of this discussion was to re-assess the current and future land use opportunities related to land re-use concepts. By re-arranging cleanup sequencing is it possible to divest land sooner than originally projected for productive commercial use hence reducing the DOE long-term liability and consequently increasing an economic soft landing for those Cold-War workers. Panelists with presentations: Integrating Economic Redevelopment and Workforce Transition Into DOE Site Closure Planning (Sean Todd); Sustaining, Growing and Re-Developing DOD/DOD Facilities and Assets (Jonathan Taylor)

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Development of a Digital Twin for Electrified Aircraft Powertrain Health Management

The augmentation of aircraft powertrains with electrical power systems is a promising path to reducing aircraft fuel consumption, emissions, and noise. Like conventional propulsion systems, electrified aircraft propulsion (EAP) systems will be subject to wear and tear throughout their lifecycles. System health management for EAP will enable efficient flight and maintenance scheduling, realizing economic, safety, and reliability benefits. A digital twin is, broadly, a dynamically updated virtual representation of an individual physical asset. This paper presents a Kalman filter-based approach for the development of a digital twin for an electrified powertrain and applies the approach to an EAP controls testbed. Measurements from nominal testbed operations are used to update a nonlinear model of the testbed. A Kalman filter is then created and used to identify and isolate anomalous testbed behavior based on measurements from off- nominal operations. Results show that the Kalman filter-based digital twin can monitor individual powertrain components’ health for degradation or other changes in performance. The applicability of the presented digital twin approach to any hybrid- or fully-electrified powertrain is emphasized.

Electrified Aircraft Propulsion↗

Enabling Realistic Communications Evaluations for ADMS

Increasing penetration levels of inverter-based distributed energy resources (DERs) in distribution systems are creating challenges in system operation. Currently, wired or proprietary wireless communications are used by advanced distribution management systems (ADMS) to detect the state of the system and control the DERs for optimal operation. Wireless communications are an alternative solution that can enable connectivity between the dispersed assets used in distribution system applications. As demand for the seamless integration of distributed energy resources (DERs) continues to increase, proper networking and communications systems are becoming important to support the DER infrastructure. This report summarizes validation of a private wireless LTE network in a laboratory environment. The purpose of this work is to 1) demonstrate the effectiveness of private wireless LTE communication for grid applications and 2) provide a means of evaluating latency and overall performance of wireless communication in grid applications. First, private wireless LTE communication was validated in a direct transfer trip relaying scenario as an example of one-way communications using grid equipment. This study provided a baseline understanding of the variation in latency for seven different kinds of wireless scenarios shown in Figure A below. As expected, weak (attenuated) wireless signal-based communication yielded the widest ranges in latency. When higher priority was set for the trip signal communication, this resulted in lower latency in communication timing. In the final phase of this project, the private wireless LTE network was validated using two-way communications in an advanced distribution management system (ADMS) testbed which was developed in the ESIF at NREL. The purpose of this was to study the impact of wireless communication on grid performance.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Future Assets, Student Talent (FAST)

Future Assets, Student Talent (FAST) motivates and prepares talented students with disabilities to further their education and achieve High Tech and professional employment. The FAST program is managed by local professionals, business, and industry leaders; it is modeled after High School High Tech project TAKE CHARGE started in Los Angeles in 1983. Through cooperative efforts of Alabama Department of Education, Vocational Rehabilitation, Adult and Children Services, and the President's Committee on Employment of People with Disabilities, north central Alabama was chosen as the second site for a High School High Tech project. In 1986 local business, industry, education, government agencies, and rehabilitation representatives started FAST. The program objectives and goals, results and accomplishments, and survey results are included.

Source record↗

Earth Independent Medical Operations [EIMO] Definition Workshop

As the vanguard of human spaceflight increasingly transitions from one of low Earth orbit (LEO) to Lunar and subsequently Martian missions, there is a commensurate imperative for Earth-based medical authority to transition to space-based assets for the continued assurance of optimal astronaut health and performance. The transition to Earth Independent Medical Operations (EIMO) will be a process that enables progressively resilient systems and crews to reduce risk and enhance wellness and overall mission success for deep space exploration. Terrestrial assets will continue to be paramount in pre-mission screening, planning, maintenance, and prevention. Yet on-board care, response to unexpected medical events, and management of communication delays and dropouts will increasingly become the purview of the crew for primary management.

John Lemery↗

Making Commercial Whole Building Program Delivery Easier and Less Risky Greg Thomas, Performance Systems Development

Whole building commercial programs can be challenging to deliver due to their complexity and scope. A broad suite of Federal tools and reference standards can be leveraged to reduce program cost and risk, and improve scalability. The OpenEfficiency Initiative (OEI) is a DoE funded effort to expand the deployment of Federal tools and reference standards into whole building commercial efficiency programs. OEI is developing an open source data exchange platform which is being informed and motivated by pilots.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Combustion Performance and Emissions Optimization through Integration of Miniaturized High Temperature Multi Process Monitoring System

The main objective of this research program is to design, manufacture, and demonstrate a miniaturized, multi-process, monitoring system (mMPMS) for boiler condition management and easy system deployment to obtain a higher spatial resolution. This system will facilitate a Condition-Based Maintenance (CBM) philosophy that actively monitors the health of assets to predict and prevent failures and maximize availability and generating capacity at a reduced cost. CBM systems can provide boiler data that the advanced process control (APC) system can utilize for plant performance optimization, which is increasingly relevant as coal power plants shift from predominantly base-load operation to predominantly transient operation involving large load swings. The mMPMS is based on an electrochemical sensor that provides a real-time indication of the risk of damage to key locations in the radiant or convective section of a coal-fired boiler such as metal loss rates, heat flux, metal surface temperature, and deposit thickness. These indications can be utilized to optimize boiler performance as well as improve boiler availability in conjunction with corresponding operating conditions. This monitoring system was developed and tested in the high-temperature regions of coal-fired utility boilers in this project but can be applied to many other industries and applications as well. The new sensor design, leveraging the existing electrochemical noise-based monitoring system, is small enough to be installed through the webbing of the waterwalls without the need for long shut-downs to bend tubes and to make it feasible to obtain high spatial resolution in the boiler. Data can be transferred to the plant distributed control system (DCS) and any other control system. The sensor body that houses the sensor assembly was designed to ensure good conductive contact with boiler tubes to ensure the sensor is held at an identical temperature to the tube surface temperature. The data acquisition and signal conditioning modules were redesigned into a small footprint with optimized cooling of the module. System software was developed specifically for the new signal conditioning module and is compatible with plant PLCs. After the preliminary testing at a pilot-scale facility, five mMPMS were installed at a full-scale pulverized coal-fired plant, Basin Electric Power Cooperative’s Leland Olds Unit 1. The systems were demonstrated over a 6-week period during typical operation. Sensor measurements of deposit thickness were validated during the demonstration and subsequently leveraged to determine sensor-based boiler cleaning strategies. These strategies have the benefit of reduced thermal stresses on boiler tubes from over-cleaning and improved boiler water management. At the end of the project, continued development of the sensor technology was carried out at PacifiCorp’s Hunter Station. REI leveraged the permanent installation of the mMPMS in Unit 3 made possible by DOE funding on a separate program. The work at Hunter Plant focused on application of machine learning and artificial intelligence-based models for integration of sensor signals into control and optimization of Hunter Unit 3 processes.

Advanced Sensors, Corrosion, Ash Deposition, Optim↗

Combustion Performance and Emissions Optimization Through Integration of a Miniaturized High-Temperature Multi Process Monitoring System

The main objective of this research program is to design, manufacture, and demonstrate a miniaturized, multi-process, monitoring system (mMPMS) for boiler condition management and easy system deployment to obtain a higher spatial resolution. This system will facilitate a Condition-Based Maintenance (CBM) philosophy that actively monitors the health of assets to predict and prevent failures and maximize availability and generating capacity at a reduced cost. CBM systems can provide boiler data that the advanced process control (APC) system can utilize for plant performance optimization, which is increasingly relevant as coal power plants shift from predominantly base-load operation to predominantly transient operation involving large load swings. The mMPMS is based on an electrochemical sensor that provides a real-time indication of the risk of damage to key locations in the radiant or convective section of a coal-fired boiler such as metal loss rates, heat flux, metal surface temperature, and deposit thickness. These indications can be utilized to optimize boiler performance as well as improve boiler availability in conjunction with corresponding operating conditions. This monitoring system was developed and tested in the high-temperature regions of coal-fired utility boilers in this project but can be applied to many other industries and applications as well. The new sensor design, leveraging the existing electrochemical noise-based monitoring system, is small enough to be installed through the webbing of the waterwalls without the need for long shut-downs to bend tubes and to make it feasible to obtain high spatial resolution in the boiler. Data can be transferred to the plant distributed control system (DCS) and any other control system. The sensor body that houses the sensor assembly was designed to ensure good conductive contact with boiler tubes to ensure the sensor is held at an identical temperature to the tube surface temperature. The data acquisition and signal conditioning modules were redesigned into a small footprint with optimized cooling of the module. System software was developed specifically for the new signal conditioning module and is compatible with plant PLCs. After the preliminary testing at a pilot-scale facility, five mMPMS were installed at a full-scale pulverized coal-fired plant, Basin Electric Power Cooperative’s Leland Olds Unit 1. The systems were demonstrated over a 6-week period during typical operation. Sensor measurements of deposit thickness were validated during the demonstration and subsequently leveraged to determine sensor-based boiler cleaning strategies. These strategies have the benefit of reduced thermal stresses on boiler tubes from over-cleaning and improved boiler water management. At the end of the project, continued development of the sensor technology was carried out at PacifiCorp’s Hunter Station. REI leveraged the permanent installation of the mMPMS in Unit 3 made possible by DOE funding on a separate program. The work at Hunter Plant focused on application of machine learning and artificial intelligence-based models for integration of sensor signals into control and optimization of Hunter Unit 3 processes.

Advanced Sensors, Corrosion, Ash Deposition, Optim↗

Combustion Performance and Emissions Optimization Through Integration of a Miniaturized High-Temperature Multi Process Monitoring System

The main objective of this research program is to design, manufacture, and demonstrate a miniaturized, multi-process, monitoring system (mMPMS) for boiler condition management and easy system deployment to obtain a higher spatial resolution. This system will facilitate a Condition-Based Maintenance (CBM) philosophy that actively monitors the health of assets to predict and prevent failures and maximize availability and generating capacity at a reduced cost. CBM systems can provide boiler data that the advanced process control (APC) system can utilize for plant performance optimization, which is increasingly relevant as coal power plants shift from predominantly base-load operation to predominantly transient operation involving large load swings. The mMPMS is based on an electrochemical sensor that provides a real-time indication of the risk of damage to key locations in the radiant or convective section of a coal-fired boiler such as metal loss rates, heat flux, metal surface temperature, and deposit thickness. These indications can be utilized to optimize boiler performance as well as improve boiler availability in conjunction with corresponding operating conditions. This monitoring system was developed and tested in the high-temperature regions of coal-fired utility boilers in this project but can be applied to many other industries and applications as well. This project leveraged the existing electrochemical noise-based monitoring system and the new sensor design is small enough to be installed through the webbing of the waterwalls without the need for long shut-downs to bend tubes and to make it feasible to obtain high spatial resolution in the boiler. Data is transferred to the plant distributed control system (DCS) and any other control system. The sensor body that houses the sensor assembly was designed to ensure good conductive contact with boiler tubes to ensure the sensor is held at an identical temperature to the tube surface temperature. The data acquisition and signal conditioning modules were redesigned into a small footprint with optimized cooling of the module. System software was developed specifically for the new signal conditioning module and is compatible with plant PLCs. After the preliminary testing at a pilot-scale facility, five mMPMS were installed at a full-scale pulverized coal-fired plant, Basin Electric Power Cooperative’s Leland Olds Unit 1. The systems were demonstrated over a 6-week period during typical operation. Sensor measurements of deposit thickness were validated during the demonstration and subsequently leveraged to determine sensor-based boiler cleaning strategies. These strategies have the benefit of reduced thermal stresses on boiler tubes from over-cleaning and improved boiler water management. At the end of the project, continued development of the sensor technology was carried out at PacifiCorp’s Hunter Station. REI leveraged the permanent installation of the mMPMS in Unit 3 made possible by DOE funding on a separate program. The work at Hunter Plant focused on application of machine learning and artificial intelligence-based models for integration of sensor signals into control and optimization of Hunter Unit 3 processes.

Advanced Sensors, Corrosion, Ash Deposition, Optim↗

D and D knowledge management information tool - a web based system developed to share D and D knowledge worldwide

Deactivation and decommissioning (D and D) work is a high risk and technically challenging enterprise within the U.S. Department of Energy complex. During the past three decades, the DOE's Office of Environmental Management has been in charge of carrying out one of the largest environmental restoration efforts in the world: the cleanup of the Manhattan Project legacy. In today's corporate world, worker experiences and knowledge that have developed over time represent a valuable corporate asset. The ever-dynamic workplace, coupled with an aging workforce, presents corporations with the ongoing challenge of preserving work-related experiences and knowledge for cross-generational knowledge transfer to the future workforce [5]. To prevent the D and D knowledge base and expertise from being lost over time, the DOE and the Applied Research Center at Florida International University (FIU) have developed the web-based Knowledge Management Information Tool (KM-IT) to capture and maintain this valuable information in a universally available and easily accessible and usable system. The D and D KM-IT was developed in collaboration with DOE Headquarters (HQ), the Energy Facility Contractors Group (EFCOG), and the ALARA [as low as reasonably achievable] Centers at Savannah River Sites to preserve the D and D information generated and collected by the D and D community. This is an open secured system that can be accessed from https://www.dndkm.org over the web and through mobile devices at https://m.dndkm.org. This knowledge system serves as a centralized repository and provides a common interface for D and D-related activities. It also improves efficiency by reducing the need to rediscover knowledge and promotes the reuse of existing knowledge. It is a community-driven system that facilitates the gathering, analyzing, storing, and sharing of knowledge and information within the D and D community. It assists the DOE D and D community in identifying potential solutions to their problem areas by using the vast resources and knowledge base available throughout the global D and D community. The D and D KM-IT offers a mechanism to the global D and D community for searching relevant D and D information and is focused on providing a single point of access into the collective knowledge base of the D and D community within and outside of the DOE. Collecting information from subject matter specialists, it builds a knowledge repository for future reference archiving Lessons Learned, Best Practices, ALARA reports, and other relevant documents and maintains a secured collaboration platform for the global D and D community to share knowledge. With the dynamic nature and evolution of the D and D knowledge base due to multiple factors such as changes in the workforce, new technologies and methodologies, economics, and regulations, the D and D KM-IT is being developed in a phased and modular fashion. (authors)

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Nuclear waste calorimeter for very large drums with 385 litres sample volume

Calorimetry is a very precise and well adapted tool for the classification of drums containing nuclear waste material depending on their level of activities (low, medium, high). A new calorimeter has been developed by SETARAM Instrumentation and the CEA Valduc in France. This new calorimeter is designed for drums having a volume bigger than 100 liters. It guarantees high operator safety by optimizing drum handling and air circulation for cooling, and optimized software for direct measurement of the quantity of nuclear material. The LVC1380 calorimeter makes it possible to work over the range 10 to 3000 mW, which corresponds to approximately 0.03 to 10 g of tritium or 3 to 955 g of {sup 241}Pu in a volume up to 385 liters. This calorimeter is based on the heat flow measurement using Peltier elements which surround the drum in the 3 dimensions and therefore measure all the heat coming from the radioactive stuff whatever its position inside the drum. Calorimeter's insulating layers constitute a thermal barrier designed to filter disturbances until they represent less than 0.001 Celsius degrees and to eliminate long term disturbances associated, for example, with laboratory temperature variations between day and night. A calibration device based on Joule effect has also been designed. Measurement time has been optimized but remains long compared with other methods of measurement such as gamma spectrometry but its main asset is to have a good accuracy for low level activities.

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