Standard Reference Data Program Research Articles

Big Data Quality Assurance Through Data Traceability: A Case Study of the National Standard Reference Data Program of Korea

In the era of big data, the scientific and social demand for quality data is aggressive and urgent. This paper sheds light on the expanded role of metrology of verifying validated procedures of data production and developing adequate uncertainty evaluation methods to ensure the trustworthiness of data and information. In this regard, I explore the mechanism of the national standard reference data (SRD) program of Korea, which connects various scientific and social sectors to metrology by applying useful metrological concepts and methods to produce reliable data and convert such data into national standards. In particular, the changing interpretation of metrological key concepts, such as “measurement,” “traceability,” and “uncertainty,” will be explored and reconsidered from the perspective of data quality assurance. As a result, I suggest the concept of “data traceability” with “the matrix of data quality evaluation” according to the elements of a data production system and related evaluation criteria. To conclude, I suggest social and policy implications for the new role of metrology and standards for producing and disseminating reliable knowledge sources from big data.

Towards Reference Viscosities of Carbon Monoxide and Nitrogen at Low Density Using Measurements between 290K and 680K as well as Theoretically Calculated Viscosities

An all-quartz oscillating-disk viscometer of very high precision was used to determine the temperature dependence of the viscosities of carbon monoxide and nitrogen at low densities. The measurements were based on a single calibration at room temperature with a value theoretically calculated on the basis of an accurate ab initio pair potential for helium and the kinetic theory of dilute monatomic gases. The uncertainty of the experimental data is conservatively estimated to be ±0.15% at room temperature increasing to ±0.20% at the highest temperature of 682 K. The new data are compared with values recommended by the National Institute of Standards and Technology in the framework of its Standard Reference Data Program REFPROP as well as with experimental data from the literature. Whereas the REFPROP values for nitrogen can be considered as reference values, the new experimental data for carbon monoxide are up to 2% higher than the REFPROP values and should be taken into consideration for a new correlation. The temperature dependence of the viscosities calculated theoretically using ab initio intermolecular potential energy hypersurfaces for carbon monoxide and nitrogen and the kinetic theory of dilute molecular gases should be used for extrapolating the viscosity correlations of both gases to low and high temperatures. In addition, the viscosity ratio of carbon monoxide to nitrogen is investigated with the purpose to establish an improved correlation for carbon monoxide.

Complex Phosphorus Thermochemistry. Volume-Based Thermodynamics and the Estimation of Standard Enthalpies of Formation of Gas phase Ions: ΔfH°(PCl4+, g) and ΔfH°(PCl6−, g)

Energy-resolved collision-induced dissociation in a flowing afterglow-guided ion beam tandem mass spectrometer has recently enabled the accurate determination of the standard enthalpy of formation of the gaseous phosphorus pentachloride cation, Delta(f)H(o) ([PCl4(+)], g), found to be 414 +/- 17 kJ mol(-1) (giving a value of 378 +/- 18 kJ mol(-1) at 0 K). Such experimental values for the standard enthalpy of formation of gas phase complex are now being incorporated into the NIST standard reference data program. Such results, can, inter alia, provide a benchmark by which to test earlier computationally based methods which were made to estimate such quantities in the absence of any experimental data. The establishment of this value experimentally also affords us with the opportunity to explore the likely success of newer, simpler approaches. Previous large-scale direct minimization computations to estimate this (and other) standard enthalpies of formation match very well these new experimental results. This paper raises the question as to whether the much simpler volume-based thermodynamics (VBT) approach could yield equally satisfactory results and so circumvent, completely, the need for detailed modeling of the lattices involved. The conclusion is that the VBT approach portrays the extremely complex thermodynamics quite adequately. Thus for the purposes of obtaining basic thermodynamic data, complex modeling of the underlying structures involved may no longer be necessary. At least this should be the case for highly symmetrical ions, like PCl4(+), where detailed packing with counterions is possibly less important than in other cases and where covalent interactions (less easily modeled) with neighboring ions is unlikely to be strongly featured. Other gaseous complex ion enthalpies of formation are also predicted here.

Web Thermo Tables - an On-Line Version of the TRC Thermodynamic Tables.

It has long been understood that availability of thermophysical and thermochemical property data is vital to scientific research and industrial design. For over 65 years, the Thermodynamics Research Center (TRC) has been publishing tables of critically evaluated data covering physical and thermodynamic properties of pure compounds, TRC Tables-Hydrocarbons and TRC Tables-Non-Hydrocarbons. Over their long history, the TRC Tables have always been valued as a reputable source of evaluated thermophysical and thermodynamic data. To facilitate more flexible, convenient, and up-to-date access to the data, here, we present the release of the on-line version of the TRC tables, Web Thermo Tables (WTT). Presently, WTT contains data for 7838 compounds and over 950,000 evaluated data points. The tabulated information includes critical properties, vapor pressures and boiling temperatures, phase transition properties, volumetric properties, heat capacities and derived properties, transport properties, reaction state-change properties, as well as index of refraction, surface tension, and speed of sound. Various search options and data plotting capabilities are provided via the Web interface. WTT are distributed through the NIST Standard Reference Data Program [1].

Review of numerical simulation of capillary tube using refrigerant mixtures

A detailed one-dimensional steady and transient state numerical simulation of the thermal and fluid-dynamic behaviour of capillary tube expansion devices considering metastable region and working with pure and mixed refrigerants has been developed and presented in previous works [Appl. Therm. Eng. 22 (2002) 173; Appl. Therm. Eng. 22 (2002) 379]. The discretized governing equations are coupled using an implicit step-by-step method. Due to the changes observed in the thermo-physical properties of mixtures using REFPROP v7.0 [Reference Fluid Thermodynamic and Transport Properties, NIST Standard Reference Database 23, Gaithersbug, MD 20899, USA, 2002] compared to REFPROP v5.0 [NIST Thermodynamic Properties of Refrigerants and Refrigerant Mixtures Database, Standard Reference Data Program, Gaithersbug, MD 20899, USA (February 1996)]; an extensive comparison of the numerical simulation developed with experimental data presented in the technical literature will be shown in order to demonstrate the accuracy of this detailed model. Finally, refrigerant-specific rating charts to predict in an easy way R-407C flow rates through adiabatic capillary tube are shown and used.

NIST Mechanisms for Disseminating Measurements.

The national responsibilities assigned to the National Bureau of Standards (NBS) early in the last century for providing measurement assistance and service are carried out today by the four programs that comprise the National Institute of Standards and Technology (NIST) Office of Measurement Services (OMS). They are the Calibration Program (CP), the Standard Reference Materials Program (SRMP), the Standard Reference Data Program (SRDP), and the Weights and Measures Program (W&MP). Organized when the U.S. Congress changed the NBS name to NIST, the OMS facilitates access to the measurement and standards activities of NIST laboratories and programs through the dissemination of NIST products, data, and services. A brief historical introduction followed by a perspective of pivotal measurement developments from 1901 to the present and concluding with a look to the future of NIST measurement services in the next decade of the new millennium are presented for each OMS program.

Special report: NIST workshop on reference data for the properties of biomaterials.

A workshop on Reference Data for Biomaterials was held at the National Institute of Standards and Technology (NIST) on July 27, 2000. The primary purpose of the workshop was to determine whether needs existed for the establishment of reference data (RD) databases on the properties of biomaterials. Special attention was given to critiqued RD such as those traditionally found in databases that are established within the NIST Standard Reference Data Program. Critiqued data are data that have been critically evaluated for issues dealing with components of uncertainty, experimental design (details, descriptions, and appropriateness), measurement methods (appropriateness), conclusions drawn from the data, and so forth. Among the workshop's 65 registrants were representatives from industry, the National Institutes of Health (NIH), the Food and Drug Administration (FDA), and academia. These joined with NIST staff to address reference biomaterial property database needs within five categories: orthopedic, cardiovascular, ophthalmologic, tissue-engineered, and dental biomaterials. A general session on other issues focused specifically on database accesses (portals), contents, and maintenance. While the workshop's intended focus was on critiqued RD, it was suggested that closely related issues be considered as well. In this way, a more comprehensive assessment of opportunities for the cooperation of NIST with the biomaterials community might be developed. As a result, the needs for noncritiqued data and for reference materials (RMs), useful for developing data, also became a part of the focus of the workshop. Hence, this article presents the results from the breakout sessions of the workshop according to two categories: reference data and databases, and reference materials. In the following summary, the workshop is presented in the following order: An introduction to databases, resource presentations, action items identified in breakout sessions, assessment of resources (personnel and monetary) needed to work on action items, and portals for databases. Except for the individual concurrent breakout sessions themselves, all other sessions of the workshop were participated in fully by those in attendance.

A Formulation for the Static Permittivity of Water and Steam at Temperatures from 238 K to 873 K at Pressures up to 1200 MPa, Including Derivatives and Debye–Hückel Coefficients

A new formulation is presented of the static relative permittivity or dielectric constant of water and steam, including supercooled and supercritical states. The range is from 238 K to 873 K, at pressures up to 1200 MPa. The formulation is based on the ITS-90 temperature scale. It correlates a selected set of data from a recently published collection of all experimental data. The set includes new data in the liquid water and the steam regions that have not been part of earlier correlations. The physical basis for the formulation is the so-called g-factor in the form proposed by Harris and Alder. An empirical 12-parameter form for the g-factor as a function of the independent variables temperature and density is used. For the conversion of experimental pressures to densities, the newest formulation of the equation of state of water on the ITS-90, prepared by Wagner and Pruss, has been used. All experimental data are compared with the formulation. The reliability of the new formulation is assessed in all subregions. Comparisons with previous formulations are presented. Auxiliary dielectric-constant formulations as functions of temperature are included for the saturated vapor and liquid states. The pressure and temperature derivatives of the dielectric constant and the Debye–Hückel limiting-law slopes are calculated, their reliability is estimated, and they are compared with experimentally derived values and with previous correlations. All equations are given in this paper, along with short tables. An implementation of this formulation for the dielectric constant is available on disk [A. H. Harvey, A. P. Peskin, and S. A. Klein, NIST/ASME Steam Properties, NIST Standard Reference Database 10, Version 2.1, Standard Reference Data Program, NIST, Gaithersburg, MD (1997)].

Computer program for computing the properties of seventeen fluids

Modifications and additions to the MIPROPS computer program for calculating the thermophysical properties of 17 fluids are described. These changes include adding new fluids, new properties and a new user interface to the program; the new program will be available from the Standard Reference Data Program of the National Institute of Standards and Technology. The new program allows the user to select the input and output parameters and the units to be displayed for each parameter.