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Conferences

On the Power Dependence of Extraneous Microwave Fields in Atomic Frequency Standards

August 29, 2005

Author(s)

Steven R. Jefferts, Jon H. Shirley, Neil Ashby, Thomas P. Heavner, Elizabeth A. Donley, F Levi

We show that the frequency bias caused by distributed cavity phase has a strong dependence on microwave power. We also show that frequency biases associated...

Laser cooling and launching performance in a (1,1,1) –geometry atomic fountain

August 29, 2005

Author(s)

Elizabeth A. Donley, Thomas P. Heavner, John O'Brien, Steven R. Jefferts, F Levi

We have successfully cooled and launched cesium atoms in the (1,1,1) atomic fountain geometry at temperatures as low as 0.8 mK. This corresponds to a mean...

Evaluation of Pressure Oscillator Losses

August 29, 2005

Author(s)

Peter E. Bradley, Michael A. Lewis, Ray Radebaugh

Efficiencies of regenerative cryocoolers are influenced by losses within the pressure oscillator (compressor). An evaluation of these losses is important when...

W-band dual channel AM/PM noise measurement system - an update

August 29, 2005

Author(s)

Archita Hati, Craig Nelson, J Nava, David A. Howe, Fred L. Walls, Huascar Ascarrunz, Justin Lanfranchi, Bill Riddle

We discuss the performance of a W-band (92-96) GHz amplitude modulated (AM) and phase modulated (PM) noise measurement system. The system uses two nearly...

Vibration-induced PM Noise in Oscillators and Measurements of Correlation with Vibration Sensors

August 29, 2005

Author(s)

David A. Howe, Justin Lanfranchi, Lauren Cutsinger, Archita Hati, Craig Nelson

We present data which shows correlations between phase fluctuations in a low g-sensitive 10 MHz oven-controlled quartz oscillator (OCXO) and acceleration...

Comparison and Status of Low-noise X-band Oscillator and Amplifier Technologies

August 29, 2005

Author(s)

David A. Howe, Archita Hati

his study compares the phase noise of different classes of oscillators and amplifiers that work at X-band. Best-in-class results are presented based on recent...

Impedance Measurements of Inertance Tubes

August 29, 2005

Author(s)

Michael A. Lewis, Peter E. Bradley, Ray Radebaugh

The flow impedance of an inertance tube 5.74 mm inside diameter and 2.36 m long coupled to various reservoir volumes was measured and compared with that...

Characterization of Optical Traps Using On-Line Estimation Methods

August 26, 2005

Author(s)

Jason J. Gorman, Thomas W. LeBrun, et al

System identification methods are presented for the estimation of the characteristic frequency of an optically trapped particle. These methods are more amenable...

Generation of Correlated Photons via Degenerate Four-Wave Mixing in Microstructure Fibers

August 25, 2005

Author(s)

Jingyun Fan, Alan L. Migdall

The gain of four-wave mixing and the gain of Raman scattering in an optical fiber are not uniform with wavelength. Through systematic experimental study, we...

A Microstructure Fiber Two Photon Source With Conjugate Laser Pumps

August 25, 2005

Author(s)

Jingyun Fan, Alan L. Migdall, L Wang

We present a systematic experimental study of generating correlated photon pairs using a reversed degenerate four-wave mixing process. By overlapping a pair of...

Investigation of 3D Tyrosine-Derived Polycarbonate Scaffold for Tissue Engineering

August 25, 2005

Author(s)

J S. Stephens, Tithi Dutta Roy, Joy P. Dunkers, Aarti Rege, J Kohn

A library of tyrosine-derived polycarbonates of have been developed that share a structurally identical backbone with a rich chemical and structural diversity...

Radio Communications in Large Buildings: A Fire Department Perspective

August 24, 2005

Author(s)

Catherine A. Remley, Katherine A. MacFarland, Mike G. Worrell

Progress Toward the Second-Generation Atomic Fountain Clock at NIST

August 23, 2005

Author(s)

Elizabeth Donley, M O. Tataw, F Levi, Steven R. Jefferts, Thomas P. Heavner

We present results on the performance of two important subsystems for NIST -F2 -the second-generation atomic fountain clock at NIST. Firstly, we demonstrate the...

Correction of Stray Light in Spectrographs: Implications for Remote Sensing

August 22, 2005

Author(s)

Yuqin Zong, Steven W. Brown, Bettye C. Johnson, Keith R. Lykke, Yoshihiro Ohno

Spectrographs are used in a variety of applications in the field of remote sensing for radiometric measurements due to the benefits of measurement speed...

Linear and Generalized Linear Models for Analyzing Face Recognition Performance

August 17, 2005

Author(s)

J. R. Beveridge, Geof H. Givens, Bruce A. Draper, P. Jonathon Phillips

This paper introduces linear models (LM), generalized linear models (GLM), and generalized linear mixed models (GLMM) for analyzing performance of face...

Dynamic Modeling and Vibration Analysis of a UHV Scanning Tunneling

August 17, 2005

Author(s)

Sumanth B. Chikkamaranahalli, R. R. Vallance, Bradley N. Damazo, Richard M. Silver, James D. Gilsinn

Techniques based on scanning probe microscopy (SPM) are used to fabricate surface structures with dimensions ranging from 10 - 100mm. These structures have been...

HIV Structural and Biothermodynamics Databases: A Resource for the Pharmaceutical and Biotechnology Industry

August 12, 2005

Author(s)

Talapady N. Bhat, Yadu D. Tewari, H Rodriguez, Robert N. Goldberg

Federal agencies, academia and industries have invested heavily in the development of structural and biothermodynamics data. However, the data are still largely...

Uncertainty Budgets for Comparison Calibrations of Thermocouples

August 7, 2005

Author(s)

Dean C. Ripple, K Garrity

By means of concrete examples, we discuss the determination of an uncertainty budget for calibration of thermocouples by comparison techniques. In the first...

Chip-Scale Atomic Clocks at NIST

August 7, 2005

Author(s)

John E. Kitching, Svenja A. Knappe, Li-Anne Liew, John Moreland, Hugh Robinson, P Schwindt, V Shah, Vladislav Gerginov, Leo W. Hollberg

We describe recent efforts to develop microfabricated atomic frequency references capable of supporting a wide variety of commercial and military systems such...

Spectral Matching With an LED-Based Spectrally Tunable Light Source

August 4, 2005

Author(s)

Irena Fryc, Steven W. Brown, Yoshihiro Ohno

A spectrally tunable light source using a large number of LEDs and an integrating sphere has been designed and constructed at the National Institute of...

Shaped Pupil Coronagraphs for Planet Finding: Optimization, Manufacturing, and Experimental Results

August 4, 2005

Author(s)

Jeremy Kasdin, Ruslan Belikov, James A. Beall, Robert J. Vanderbei, Michael G. Littman, Michael Carr, Amir Give''on

Current plans call for the first Terrestrial Planet Finder mission, TPF-C, to be a monolithic space telescope with a coronagraph for achieving high contrast...

Uncertainties in Spherical Near-Field Antenna Measurements

August 3, 2005

Author(s)

Michael H. Francis, Ronald C. Wittmann, Jin-Seob Kang

A general approach is presented for estimating uncertainties in far-field parameters obtained from spherical near-field antenna measurements. The error is...

New NIST Reference Goniospectrometer

August 1, 2005

Author(s)

Gael Obein, Robert R. Bousquet, Maria E. Nadal

Coatings can be classified by either their appearance, such as glitter, or by their function, such as corrosion protection. However, pigments are currently...

A Fiber Probe for CMM Measurements of Small Features

August 1, 2005

Author(s)

Jack A. Stone Jr., Balasubramanian Muralikrishnan, John R. Stoup

We report on performance of a new form of fiber probe, which can be used in conjunction with a coordinate measuring machine (CMM) for microfeature measurement...

Methods for Evaluating the Reference Value in Laboratory Intercomparisons of Dimensional Measurements

August 1, 2005

Author(s)

Jack A. Stone Jr.

A number of methods have been proposed to evaluate the reference value for intercomparisons of laboratory measurements. Methods for establishing the reference...

Embeding MPEG-7 Metadata Within a Media File Format

August 1, 2005

Author(s)

Wo L. Chang

Embedding metadata within a media file format becomes evermore popular for digital media. Traditional digital media files such as MP3 songs and JPEG photos do...

Calibration and Standardization Issues of UV Sensors for Water Disinfection

August 1, 2005

Author(s)

Thomas C. Larason, Yoshihiro Ohno

Ultraviolet radiation (UV) effectively inactivates common pathogens found in ground and surface waters such as Cryptosporidium, Giardia and most bacterial...

Pore Pressure in High-Strength Concrete at High Temperature

August 1, 2005

Author(s)

Long T. Phan

This paper presents results of an experimental program to study the effects of elevated temperature exposure on pore pressure buildup and potential for...

A Critical Review of Second Virial Coefficients for Water Vapor with Air and With Argon

August 1, 2005

Author(s)

Peter H. Huang, Allan H. Harvey

This work reviews the current state of knowledge for the second virial coefficients of water vapor with air and with argon. Comparative tabulations of the...

Organic Semiconductor Structure and Chemistry From Near-Edge X-Ray Absorption Fine Structure (NEXAFS) Spectroscopy

August 1, 2005

Author(s)

Dean M. DeLongchamp, Eric K. Lin, Daniel A. Fischer

The ability to measure the structural development of organic semiconductor films and correlate it to the electrical characteristics of organic devices such as...

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