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A logical model of conceptual integrity in data integration
No full textConceptual integrity is required for the result of data integration to be cohesive and sensible. Compromised conceptual integrity results in ""semantic faults,"" which are commonly blamed for latent integration bugs. A logical model of conceptual integrity in data integration and a simple example application are presented. Unlike constructive models that attempt to prevent semantic faults, this model allows both correct and incorrect integrations to be described. Imperfect legacy systems can therefore be modeled, allowing a more formal analysis of their flaws and the possible remedies
Thermal evaluation of scorched graphite-epoxy panels by infrared scanning
No full textA simple measurement system is described for evaluating damage to graphite-epoxy panels, such as those used in high-performance aircraft. The system uses a heating laser and infrared imaging system to measure thermal performance. Thermal conductivity or diffusivity is a sensitive indicator of damage in materials, allowing this thermal measurement to show various degrees of damage in graphite-epoxy composites. Our measurements track well with heat-flux damage to graphite epoxy panels. This measurement system, including analysis software, could easily be used in the field, such as on the deck of an aircraft carrier or at remote air strips
Mass absorption coefficient of tungsten and tantalum, 1450 eV to 2350 eV: Experiment, theory, and application
No full textThe mass absorption coefficients of tungsten and tantalum were measured with soft x-ray photons from 1450 eV to 2350 eV using an undulator source. This region includes the M3, M4, and M5 absorption edges. X-ray absorption fine structure was calculated within a real-space multiple scattering formalism; the predicted structure was observed for tungsten and to a lesser degree tantalum as well. Separately, the effects of dynamic screening were observed as shown by an atomic calculation within the relativistic time-dependent local-density approximation. Dynamic screening effects influence the spectra at the 25 % level and are observed for both tungsten and tantalum. We applied these results to characterize spatially-resolved spectra of a tungsten integrated circuit interconnect obtained using a scanning transmission x-ray microscope. The results indicate tungsten fiducial markers were deposited into silica trenches with a depths of 50 % and 60 % of the markers' heights
Characterization of an ellipsoidal radiometer
No full textAn ellipsoidal radiometer has been characterized using a 25 mm variable-temperature blackbody as a radiant source. This radiometer is intended for separating radiation from convection effects in fire test methods. The characterization included angular response, responsivity, and purge-gas flow effect studies. The angular response measurements showed that the reflection from the radiometer cavity was higher on one of the cavity halves relative to the other half. Further development work may be necessary to improve the angular response. The responsivity measured with reference to a transfer-standard electrical-substitution radiometer showed dependence on the distance of the radiometer from the blackbody cavity. The purge-gas had the effect of reducing the signal output nearly linearly with flow rate
Relating fresh concrete viscosity measurements from different rheometers
No full textConcrete rheological properties need to be properly measured and predicted in order to characterize the workability of fresh concrete, including special concretes such as self-consolidating concrete (SCC). It was shown by a round-robin test held in 2000 [ 1,2] that different rheometer designs gave different values of viscosity for the same concrete. While empirical correlation between different rheometers was possible, for a procedure that is supposed to ""scientifically"" improve on the empirical slump tests, this situation is unsatisfactory. To remedy this situation, a new interpretation of the data was developed. In this paper, it is shown that all instruments tested could be directly and quantitatively compared in terms of relative plastic viscosity instead of the plastic viscosity alone. This should eventually allow the measurements from various rheometer designs to be directly calibrated against known standards of plastic viscosity, putting concrete rheometry and concrete workability on a sounder materials science basis
Virtual environment for manipulating microscopic particles with optical tweezers
No full textIn this paper, virtual reality techniques are used to define an intuitive interface to a nanoscale manipulation device. This device utilizes optical methods to focus laser light to trap and reposition nano-to-microscopic particles. The underlying physics are simulated by the use of Lagrange mechanics. A unique control method for the manipulation of the particles is also provided. The user can naturally grab and steer the particles. Behind the scene, a complex computation is performed to find the new location of the potential field induced by the laser beam that would move the particles accordingly. Haptic feedback is used to constrain the steering motion within the physical capability of the potential field
Richard C. Kirby
No full textRICHARD C. KIRBY
NBS/NIST: 1948 - 1950, 1951 - 1965
B: November 22, 1922, Galesburg, Illinois
D: January 26, 2012
EDUCATION:
University of Minnesota, BEE, 1951
PRINCIPAL FIELDS:
Telecommunication and broadcasting technology, radiowave propagation, ionospheric VHF forward scatter, radio system engineering, frequency management and allocation, international telecommunication
POSITIONS HELD AT NBS (BOULDER):
Chief, Ionosphere Research Section, Radio Propagation Physics Division
Chief, Radio Communication and Systems Division
Chief, Radio Systems Division
Special Assistant for Telecommunication to the Assistant Secretary of Commerce
HONORS:
U.S. Department of Commerce: Gold Medal, 1956; Gold Medal, 1968
“Don McClellan Meritorious Service” Award, IEEE Communication Society, 1979
Award for Contribution to International Telecommunication, IEEE, in honor of Hernand and Sosthes, 1981
Regents Award for Outstanding Achievement, University of Minnesota, 1983
Award of Public Service in the Field of Telecommunication, IEEE Communication Society, 1990
Electrical Engineering Society of Poland, Gold Medal, 1992
Presidential of Poland, Medal Award, 1992
International Telecommunication Union, Silver Medal, 1992
MEMBERSHIPS:
Institute of Radio Engineers/Institute of Electrical and Electronics Engineers (Fellow)
IEEE Communications Technology Group (Chairman; International Vice President)
International Radio Consultative Committee (CCIR) of the International Telecommunication Union (ITU) (Director)
Sigma Xi
Radio Club of America (Fellow)
Popov Radio Scientific Society (Russia) (Honorary Member)
PUBLICATIONS:
Six or more published papers on radio communication including:
“Radio transmission at VHF by scattering and other processes in the lower atmosphere,” (with coauthors) Proc. I.R.E (1955)
“VHF propagation by ionospheric scattering – a survey of experimental results,” I.R.E. Trans. Communications Systems (1957
Ronald K. Eby
No full textRONALD K. EBY
NBS: 1963 - 1984
Birth: May 7, 1929, Reading, Pennsylvania
Diedune 27, 2006
Education:
Lafayette College: ScB (Physics), 1952
Brown University: MS, 1955; PhD (Physics), 1958
Principal fields:
Structure, morphology and properties of plastics, elastomers, advanced fibers, silks, composites; computational modeling, physical acoustics, ultrasonics, NDE, thermal analysis, microscopy, x-ray scattering
Positions held at NBS:
Physicist, Polymers Division
Chief, Polymer Crystal Physics Section
Chief, Polymers Division
Honors:
Sigma Xi
ASTM Award of Appreciation
Alexander von Humboldt Senior Prize
The University of Akron, Endowed Chair
American Chemistry Society, Division of Polymer Chemistry, Special Service Award
Society of Plastics Engineers, International Research Award
Japanese Government Research Award
NASA, Certificate of Recognition
Memberships:
American Chemical Society (Chair, Division of Polymer Chemistry)
American Physical Society (Chair, Executive Committee, Division of High Polymer Physics (Fellow)
Acoustical Society of America (Fellow)
ASTM Committee D20 (Plastics), (Chair)
Max Planck Institut für Polymerforschung (Chair, International Scientific Advisory Board)
Society of Plastics Engineers (Fellow)
North American Thermal Analysis Society (Fellow)
Publications:
Over one hundred eighty publications including:
“First Order Transitions in Crystalline Polymers,” J Appl Phys. 34 (1963) 2442.
“Thermodynamics & Crystallization of Random Copolymers,” (with I.C. Sanchez) Macromolecules, 8 (1975) 638.
“Energy Calculations of the Crystal Structure of the Low-Temperature Phase II of Polytetrafluoroethylene,” (with B.L. Farmer) Polymer, 22 (1981) 1487