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Projects/Programs

Topic Area
Displaying 1426 - 1450 of 1667

Speaker and Language Recognition

Ongoing
Current Speaker and Language Recognition technology activities: Speaker Recognition Evaluation series: (1996-) A biennial NIST evaluation of fully automated text-independent speaker recognition technology. View the 2012 NIST SRE report. Human Assisted Speaker Recognition Evaluation series: (2010- )...

Special Functions

Ongoing
Special function evaluation is among the more venerable problems of numerical mathematics and remains a staple for engineers, physicists, and scientific computation. What is more, the need for detailed numerical evaluations grows steadily as new quantitative theories are developed for an increasing...

Spectral Reflectance and Transmittance

Ongoing
NIST serves as the nation's primary source for spectral reflectance and transmittance measurements from 250 nm to 2500 nm. Our reflectance and transmittance measurements support the measurement infrastructure of communities involved in optics, photonics, color technology, instrument manufacturing...

Spectral responsivity measurement

Ongoing
The spectral responsivities of typical photodiodes that are used in the ultraviolet, visible, and near-infrared and calibrated by the SCFs are shown below. **Any commercial equipment, instruments, or materials mentioned are identified to foster understanding. Such identification does not...

Spectrophotometry

Ongoing
NIST uses spectrophotometric techniques to measure the optical properties of materials for dissemination of national measurement scales to its stakeholders and advancing the development of standards, measurement methods, and modeling capabilities. The beneficiaries of these activities include the...

Spectroradiometry of sources

Ongoing
The spectral radiance sources in the form of tungsten-strip lamps and integrating-sphere sources are calibrated in the Facility for Spectroradiometric Calibrations (FASCAL). The measurements are performed by the use of a prism-grating double monochromator whose spectral radiance responsivity is...

Spectroscopy and Application of Solid-State Quantum Centers

Ongoing
Quantum color centers in wide-bandgap semiconductors have spin and optical degrees of freedom, which can be leveraged for applications such as sensing and single-photon generation. In materials like diamond and silicon carbide, long spin lifetimes and quantum coherence times enable sensitive...

Spectrum Coexistence Metrology

Ongoing
The overarching goal of the Coexistence Project is to support the development, evaluation, and optimization of spectrum sharing techniques. These techniques include methods to model, simulate, and physically measure the ability of wireless communications systems to maintain their functional...

Spectrum Sensing and Noise

Ongoing
Reports in the NIST Technical Notes series were extensive measurements of radiated noise. Researchers also made key early contributions to standardizing guided-wave noise measurements in microwave systems. These contributions continue to underpin our ongoing work, but basic applications and hardware...

Spectrum Sharing & Sensing

Ongoing
The presence of large numbers of licensed and unlicensed spectrum users has already increased the environmental noise floor well above conventional thermal noise levels. Nevertheless, a quantitative assessment of the existing noise floor in today’s communication world is not yet available. As a...

Spectrum Tracking in Power Grid Systems

Completed
The increasing deployment of residential renewables and an extensive use of nonlinear devices in the distribution system can produce undesirable harmonic distortions. Such distortions can severely impact phase/frequency estimation in power systems, especially distributed grid systems. For grid...

Speech Analytics

Ongoing
Current speech analytics work: OpenSAT is a new speech analytic evaluation series designed to include developers from multiple speech analytic technologies where common datasets are used in NIST evaluations. The goal is to bring together developers focused on different speech analytic tasks to...

Spinor Condensates and Ultracold Collisions

Ongoing
A Bose-Einstein condensate (BEC) collapses the wavefunctions of many particles in to a single quantum state. In a spinor BEC the atoms can be in a superposition of internal quantum states. Thus, a BEC of spin-1 particles, like the F = 1 ground state of Na atoms, can be thought of as being a single...

Spin-orbit interaction in devices and quantum materials

Ongoing
The spin degree of freedom can provide a basis for next-generation electronic devices. Spintronic devices typically include materials with magnetic ordering, such as ferromagnets or antiferromagnets. The state of the magnetization influences charge and spin current through an effect known as...

Spintronics for Neuromorphic Computing

Ongoing
Magnetic tunnel junctions (see Fig. 1) consist of two thin films of ferromagnetic material separated by a few atomic layers of an insulating material. The insulator is so thin that electrons can tunnel quantum mechanically through it. The rate at which the electrons tunnel is affected by the...

Springback

Ongoing
Springback, or the elastic change in shape when a part is released from the manufacturing process, has been a problem for decades and accounts for a significant fraction of the expense that the US auto industry spends each year trying out die sets for new body designs. The inability to predict the...

Standard Platinum Resistance Thermometer Calibration Laboratory (SPRTCL)

Ongoing
The SPRTCL provides an extensive list of calibration services that cover the whole temperature range for which long-stem SPRTs, including high-temperature SPRTs, are the ITS-90 interpolation artifacts. This range spans from the triple point of argon (-189.3442 °C) to the freezing point of silver...

Standard Reference Materials for Hexavalent Chromium in Contaminated Soil

Completed
During the last century, chromate and dichromate chemical production facilities processed considerable amounts of chromite ore for industrial manufacturing purposes. The waste material from these operations called chromite ore processing residue (COPR) was disposed of in waste sites across the...

Standard Reference Materials: Standardization of 232U (SRM 4324c)

Ongoing
The certified massic activity for 232U was obtained by 4παβ LS spectrometry with two commercial LS counters. The beta detection efficiencies for the 232U daughters were calculated using the MICELLE2 code for the CIEMAT/NIST efficiency tracing (CNET) method with composition-matched LS cocktails of a...

Standard Reference Materials: Standardization of 243Am (SRM 4332f)

Ongoing
The certified massic activity for 243Am was obtained by 4παβ LS spectrometry with two commercial LS counters. The beta detection efficiencies for the 243Am daughter ( 239Np) were calculated using the CN2003 code for the CIEMAT/NIST efficiency tracing (CNET) method with composition-matched LS...

Standard Reference Materials: Standardization of 239Pu (SRM 4330d)

Ongoing
The certified massic activity for 239Pu was obtained by 4πα liquid scintillation (LS) spectrometry with two commercial LS counters. Confirmatory measurements were performed by LS counting comparative measurements against SRM 4330d, which was also standardized in 2009 by 4pa liquid scintillation (LS)...

Standard Reference Measurements

Ongoing
State-of-the art property measurements have been the hallmark of the Fluid Properties Group for more than four decades. Many of these measurements have been carried out on one-of-a-kind instruments developed at NIST. In some cases the older instruments are still among the very best of their kind...

Standard Solution SRMs Provide Traceability for Millions of Measurements

Ongoing
Literally millions of measurements of elemental composition are performed each year worldwide. The vast majority of these measurements depend upon reference materials for establishing traceability of results to the SI. Leveraged through commercial CRM producers, the NIST SRM 3100 series provides an...
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