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Projects/Programs

Topic Area
Displaying 176 - 200 of 1643

Building Measurement Confidence for Cell Characterization

Ongoing
NIST collaborates with key stakeholders in industry, other government agencies, and academia to develop measurement assurance strategies and advanced measurement capabilities for cell characterization. Data and concepts developed through workshops and laboratory programs inform the development of

Building System Economics

Ongoing
Objective To develop and deploy transparent, open source standards-based data and tools that quantify the life-cycle performance of building technologies and systems through parallel activities focused on developing, releasing, and expanding capabilities and adoption of: (1) an economic evaluation

Building Trust in Forensic Science: Footwear Analysis

Ongoing
Starting in 2015, SED staff members began reviewing published literature on the recommended practice for forensic examiners to provide likelihood ratios (LRs) as a weight of evidence to summarize their findings in reports or testimony. While several stated motivations for providing likelihood ratios

Building-Level Seismic Performance Assessment

Ongoing
Objective The objective of this project is to better understand the seismic performance of buildings designed in areas of medium-to-high seismicity and to identify and evaluate ways to enhance the seismic performance of buildings through advances in design approaches, including conventional and low

Calculation of optical constants and dielectric response

Ongoing
By optical properties, we mean those of the following sort: the index of refraction n and the index of absorption k, from which one can calculate the dielectric function, loss function, absorption coefficient, reflectance, and so forth from standard formulas. All of these quantities, it should be

Calibration of Force Transducers

Ongoing
The calibration report describes the relationship between the applied force and the measured deformation, either in electrical or mechanical units. A transducer can be calibrated using (1) a readout device furnished by the customer, in which case the transducer and the readout device are calibrated

Calibration of Mass Standards

Ongoing
Redefinition of the Kilogram and Consensus Value of the Kilogram The unit of mass was redefined in May 2019 as part of a general revision to the International System of Units (SI). See SI Redefinition. The kilogram is now defined by the Planck constant. The International Prototype Kilogram (IPK) no

Calibration Services: High-Dose Dosimetry

Ongoing
NIST developed the alanine dosimetry system in the early 1990's to replace radiochromic dye film dosimeters. Later in the decade the alanine system was firmly established as a transfer service for high-dose radiation dosimetry and an integral part of the internal calibration scheme supporting these

Calibration Services: Low-Energy Photon Brachytherapy Sources

Ongoing
Since 1999, over 1,500 seeds of more than 40 different designs from 18 manufacturers have been calibrated using the WAFAC. On-site characterization at seed manufacturing plants for quality control, as well as at therapy clinics for treatment planning, relies on well-ionization chamber measurements

Calibration Services: New Calibration Facility for X-Ray Air Kerma

Ongoing
The NIST x-ray calibration facility is composed of a suite of rooms that includes the 11 m by 7 m calibration range, a dedicated equipment room, connected by custom shielding ports for communication with the x-ray tubes in the radiation area, an operator control center with a viewing window and

Calibration of Space Weather Observational Instruments at NIST

Ongoing
Space-weather events are naturally occurring phenomena caused by activity on the Sun that affect us here on Earth. Solar storms can impact technology we rely on daily, like e.g. the Global Positioning System (GPS), communication satellites, and electric power grids. Various phenomena that originate

Calibrations: Californium Neutron Irradiation Facility

Ongoing
A high-activity Cf-252 source (~10 10 neutrons/s as of May 2024) is housed in a large (approximately 15 m x 10 m x 10 m high) room with concrete walls, floor, and ceiling (see photograph) at a depth of 10 meters-water-equivalent. In addition, there are two monoenergetic neutron generators for 2.5

Calibrations: Neutron Device Calibrations

Ongoing
The Neutron Physics Group calibrates neutron radiation detectors used for personnel protection and irradiates personnel dosimeters in standard neutron fields. The fields are produced by unmoderated 252Cf and 252Cf moderated with a D 2O sphere (represented by the gray sphere near the center of the

Calibrations: Neutron Source Strength

Ongoing
Calibrations are performed using the manganous sulfate bath technique in which the emission rate of the source to be calibrated is compared to the emission rate of NBS–1, the national standard Ra–Be photo-neutron source. Neutron source calibrations typically have a relative expanded uncertainty ( k

Calibrations: Portable Manganese Sulfate Bath

Ongoing
The Manganese Sulfate Bath uses a sphere of neutron-absorbing material that surrounds a neutron source. The induced radioactivity is a measure of the neutron source strength. Lower intensity sources provide less manganese activation, resulting in a reduced signal over background, and this signal-to

Calibrations: Radioactivity Standard Reference Material Program

Ongoing
NIST radioactivity SRMs represent the national basis for accurate radioactivity measurements. SRMs for radioactivity measurements can typically be classified into three general categories: (1) environment and nuclear power, (2) medicine, and (3) basic and applied research using or involving
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