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An Assessment of Four Divisions of the Physical Measurement
Laboratory at the National Institute of Standards and Technology:
Fiscal Year 2018 assesses the scientific and technical work
performed by four divisions of the National Institute of Standards
and Technology (NIST) Physical Measurement Laboratory. This
publication reviews technical reports and technical program
descriptions prepared by NIST staff and summarizes the findings of
the authoring panel. Table of Contents Front Matter Summary 1 The
Charge to the Panel and the Assessment Process 2 Organization and
Mission of the Physical Measurement Laboratory 3 Applied Physics
Division 4 Quantum Electromagnetics Division 5 Time and Frequency
Division 6 Quantum Physics Division 7 Key Recommendations Acronyms
The Physical Measurement Laboratory (PML) at the National Institute
of Standards and Technology (NIST) is dedicated to three
fundamental and complementary tasks: (1) increase the accuracy of
our knowledge of the physical parameters that are the foundation of
our technology-driven society; (2) disseminate technologies by
which these physical parameters can be accessed in a standardized
way by the stakeholders; and (3) conduct research at both
fundamental and applied levels to provide knowledge that may
eventually lead to advances in measurement approaches and
standards. This report assesses the scientific and technical work
performed by the PML and identifies salient examples of
accomplishments, challenges, and opportunities for improvement for
each of its nine divisions. Table of Contents Front Matter Summary
1 The Charge to the Panel and the Assessment Process 2 Applied
Physics and Quantum Electromagnetics Divisions 3 Engineering
Physics Division 4 Office of Weights and Measures 5 Quantum
Measurement Division 6 Quantum Physics Division 7 Radiation Physics
Division 8 Sensor Science Division 9 Time and Frequency Division 10
Key Suggestions for Improvement Acronyms
The National Defense Center of Excellence for Industrial Metrology
and 3D Imaging (COE-IM3DI) is conducting research to enable the
next generation of manufacturing-centric human/instrument/machine
interaction. The generalized goal of the COE-IM3DI research is to
facilitate the transition of 3D imaging technology from one
requiring highly skilled/specialized technicians to a ubiquitous
measurement capability available in real-time on the shop floor.
This long-term effort requires a detailed examination of the
current state of the art in 3D imaging and projected technology
development trends over the next ten years. In 2004, NIST produced
a seminal report on the then state of the art of the 3D Imaging
field with a particular focus on hardware requirements for
applications in manufacturing, autonomous vehicle mobility, and
construction. This report will extend that initial work
(principally with respect to software) and provide an update that
will support the needs of the COE-IM3DT research program.
A review is presented of the state of the art of smoke production
measurement, prediction of smoke impact as part of computer-based
fire modeling, and measurement and prediction of the impact of
smoke through deposition of soot on and corrosion of electrical
equipment. The literature review on smoke corrosivity testing and
damage due to smoke deposition emphasizes (despite extensive
research on smoke corrositity) the lack of validated and widely
applicable prescriptive or performance based methods to assure
electrical equipment survivability given exposure to fire smoke.
Circuit bridging via current leakage through deposited smoke was
identified as an important mechanism of electronic and electrical
equipment failure during NPP fires. In the near term, assessment of
potential damage can reasonably be based on the airborne smoke
exposure concentration and, perhaps, the exposure duration. Hence,
models that can predict the airborne smoke concentration would be
sufficient to suit short-term analysis needs. In the longer term,
it would be desirable to develop models that could estimate the
deposition behavior of smoke, as well and specifically correlate
the combination of deposited and airborne smoke to component
damage.
Bulk oxide determinations from a pair of port-land cements provides
the basis for calculation precision and accuracy values for X-ray
fluorescence (XRF) analysis for both the fused glass bead and the
pressed powder sample preparation. This report is the second in a
series on an Inter-laboratory study on chemical analyses of
hydraulic cements by X-ray fluorescence for the purpose of
estimating precision and qualification criteria. Approximately 45
laboratories provided six replicates analyzed in duplicate for two
separate port-land cements containing ca. 5 % limestone, covering
fifteen analytes, CaO, SiO2, Al2O3, Fe2O3, SO3, MgO, Na2O, K2O,
TiO2, P2O5, Mn2O3, SrO, ZnO, Cr2O3, and Cl, with the laboratories
roughly split between the two different sample preparations.
Chemical data using traditional chemical analyses (the Reference
Methods) from the Cement and Concrete Reference Laboratory (CCRL)
proficiency test program were included for comparison to the XRF
results.
Bulk oxide determinations from a pair of portland cements provides
the basis for calculation precision and accuracy values for X-ray
fluorescence (XRF) analysis for both the fused glass bead and the
pressed powder sample preparation. Approximately 45 laboratories
provided six replicates analyzed in duplicate for two separate
portland cements covering eleven analytes, CaO, SiO2, Al2O3, Fe2O3,
SO3, MgO, Na2O, K2O, TiO2, P2O5, and Cl, with the laboratories
roughly split between the two different sample preparations.
Chemical data using traditional chemical analyses (the Reference
Methods) from the Cement and Concrete Reference Laboratory (CCRL)
proficiency test program were included for comparison to the XRF
results.
To date, there is no International standard on the methods and
tests to assess the verification and validation (V&V) of
building fire evacuation models, i.e., model testers adopt
inconsistent procedures or tests designed for other model uses. For
instance, the tests presented within the MSC/Circ.1238 Guidelines
for evacuation analysis for new and existing passenger ships
provided by the International Maritime Organization are often
employed for the V&V of models outside their original context
of use (building fires instead of maritime applications). This
document discusses the main issues associated with the definition
of a standard procedure for the V&V of building fire evacuation
models. A review of the current procedures, tests (e.g. the
MSC/Circ.1238 Guidelines), and methods available in the literature
to assess the V&V of building evacuation models is provided.
The capabilities of building evacuation models are evaluated
studying their five main core components, namely 1) Pre-evacuation
time, 2) Movement and Navigation, 3) Exit usage, 4) Route
availability and 5) Flow constraints. A set of tests and
recommendations about the verification of building evacuation
models is proposed. Suggestions on simple qualitative validation
tests are provided together with examples of experimental data-sets
suitable for the analysis of different core components. The
uncertainties associated with evacuation modelling are discussed.
In particular, a method for the analysis of behavioural uncertainty
(uncertainty due to the use of distributions or stochastic
variables to simulate human behaviour in evacuation modelling) is
presented. The method consists of a set of convergence criteria
based on functional analysis. The last part of this document
presents a discussion on the definition of the acceptance criteria
for a standard V&V protocol.
Building stakeholders need practical metrics, data, and tools to
support decisions related to sustainable building designs,
technologies, standards, and codes. The Engineering Laboratory of
the National Institute of Standards and Technology (NIST) has
addressed this high priority national need by extending its metrics
and tool for sustainable building products, known as Building for
Environmental and Economic Sustainability (BEES), to whole
buildings. Whole building sustainability metrics have been
developed based on innovative extensions to life-cycle assessment
(LCA) and life- cycle costing (LCC) approaches involving building
energy simulations. The measurement system evaluates the
sustainability of both the materials and the energy used by a
building over time. It assesses the, carbon footprint of buildings
as well as 11 other environmental performance metrics, and
integrates economic performance metrics to yield science-based
measures of the business case for investment choices in
high-performance green buildings. Building Industry Reporting and
Design for Sustainability (BIRDS) applies the new sustainability
measurement system to an extensive whole building performance
database NIST has compiled for this purpose. The BIRDS database
includes energy, environmental, and cost measurements for 12 540
new commercial and non low-rise residential buildings, covering 11
building prototypes in 228 cities across all U.S. states for 9
study period lengths. The sustainability performance of buildings
designed to meet current state energy codes can be compared to
their performance when meeting four alternative building energy
standard editions to determine the impact of energy efficiency on
sustainability performance. The impact of the building location and
the investor s time horizon on sustainability performance can also
be measured.
Research funded under the Fire Safe Cigarette Act of 1990 (P.L.
101-352) has led to the development of two test methods for
measuring the ignition propensity of cigarettes. The Mock-Up
Ignition Test Method uses substrated physically similar to
upholstered furniture and mattresses: a layer of fabric over
padding. The measure of cigarette performance is ignition or
non-ignition of the substrate. The Cigarette Extinction Test Method
replaces the fabric/padding assembly with multiple layers of common
filter paper. The measure of performance is full-length burning or
self-extinguishment of the cigarette. Routine measurement of the
relative ignition propensity of cigarettes is feasible using either
of the two methods. Improved cigarette performance under both
methods has been linked with reduced real-world ignition behavior;
and it is reasonable to assume that this, in turn, implies a
significant real-world benefit. Both methods have been subjected to
interlaboratory study. The resulting reproducibilities were
comparable to each other and comparable to those in other fire test
methods currently being used to regulate materials which may be
involved in unwanted fires. Using the two methods, some current
commercial cigarettes are shown to have reduced ignition
propensities relative to the current best-selling cigarettes. *]
This is one of six volumes in the Final Report, Fire Safe Cigarette
Act of 1990. VOLUME 1. Overview: Practicability of Developing a
Performance Standard to Reduce Cigarette Ignition Propensity by
Jones-Smith, J., et al. VOLUME 3. Modeling the Ignition of Soft
Furnishings by a Cigarette by Mitler, H. E., et al. VOLUME 4.
Cigarette Fire Incident Study by Harwood, B., et al. VOLUME 5.
Toxicity Testing Plan by Lee, B. C., et al. VOLUME 6. Societal
Costs of Cigarette Fires by Ray, D. R., et al.
FAST is a collection of fire modeling tools which uses the
underlying fire model CFAST and adds the routines of FIREFORM to
provide engineering calculations of fire phenomena in compartmented
structures. This manual provides documentation and examples for
using FAST. It describes how to install the software on a computer
and provides a guide for the use of FAST using examples.
This report describes the technical accomplishments and activities
of NIST's Information Technology Laboratory for FY 1997. The work
of ITL's eight technical divisions is detailed, and interactions,
publications, papers, conferences, recognition, and other resources
are documented.
The National Institute of Standards and Technology hosted a twoday
workshop focusing on needed research on occupant behavior and
movement during building emergencies. This workshop was motivated
by a renewed interest in how buildings should be evacuated during
fire emergencies and by the desire to provide a forum for the
exchange of experiences among the fire and non-fire communities
working on emergency egress. The workshop was organized into
several sessions with specific topics areas, including codes and
standards requirements for building evacuation, building egress
strategies, and data needs for predictive models. Several
presentations were included in each session, with an extended
period for discussion at the end of each session. For each
presentation, visuals used for the presentation are included, along
with any additional information provided by the author on the
topic. For each workshop session, the session moderator prepared a
summary of key points of research interest from the presentations
and discussion.
The investigation of the collapse of a five-story reinforced
concrete flat-plate structure under construction at Cocoa Beach,
Florida is presented in this report. The investigation included
onsite inspection, laboratory tests and anlytical studies. Based on
the results of this investigation, it is concluded that the most
probable cause of the failure was insufficient punching shear
capacity in the fifth-floor slab to resit the applied construction
loads.
New technologies and research are redefining the state-of-the-art
in building evacuation. The time is right to rethink the entire
infrastructure of egress from buildings in light new opportunities
to address the economic and life-safety issues. Approximately 40
experts from a variety of disciplinary background assembled in
Warrenton, VA from April 1-3, 2008 in order to consider building
evacuation, starting with a blank sheet of paper. Structured around
the principles of Value-Focused Thinking (a text authored by
workshop moderator Ralph Keeney), the participants were encouraged
to consider values, objectives, alternatives, and metrics. This
process combined the benefits of free-thinking brainstorming with a
formalism which encouraged evaluation of the potential for new
ideas. By the conclusion of the third day, over 400 ideas had been
developed, along with metrics for future evaluation of the ideas.
Fire protection measures are needed to maintain the safety and
integrity of the Nation s building stock and to limit loss of life
and property when building fires do occur. Statistics published by
the National Fire Protection Association demonstrate that fire
protection is a major investment cost in building construction.
Therefore, ways to reduce these costs while ensuring safety are of
interest to building owners, fire protection engineers, and other
construction industry stakeholders. Although all fire protection
measures have important economic implications, the focus of this
report is on egress-related requirements in new building
construction. Recent changes in the International Building Code
have set the stage for analyzing the costs of several key
egress-related requirements. The U.S. General Services
Administration commissioned this study to conduct an economic
analysis of the use of elevators and exit stairs for occupant
evacuation and fire service access. The goal of this study is to
produce analyses of cost data suitable for evaluating improved
egress system designs that promote efficient and timely egress of
occupants, including those with disabilities, and that facilitate
more efficient fire department operations. This report tabulates
cost data for selected egress-related requirements in five
prototypical buildings. The five prototypical buildings range in
height from a 5-floor, mid-rise building to a 75- floor, high-rise
building. Cost data are tabulated in a format that facilitates
lifecycle cost analyses of selected egress-related requirements.
Incremental costs are also tabulated to help assess the
implications of changing one or more design parameters. The results
of the economic analysis for four prototypical buildings over 120
ft (37 m), with two over 420 ft (128 m) high, demonstrate that: (1)
an additional exit stair is a cost-effective alternative to the
installation of occupant evacuation elevators on a first-cost
basis; and (
There is a general concern that the US manufacturing industry has
lost competitiveness with other nations. Additive manufacturing may
provide an important opportunity for advancing US manufacturing
while maintaining and advancing US innovation. Additive
manufacturing is a relatively new process where material is joined
together layer by layer to make objects from 3D models as opposed
to conventional methods where material is removed. The US is
currently the primary user of additive manufacturing technology and
the primary producer of additive manufacturing systems. Globally,
an estimated $642.6 million in revenue was collected for additive
manufactured goods with the US accounting for an estimated $468.9
million or 72.9% of global production in 2011. Change agents for
the additive manufacturing industry can focus their efforts on
three primary areas to advance this technology: cost reduction,
accelerating the realization of benefits, and increasing the
benefits of additive manufacturing. Significant impact on these
areas may be achieved through the reduction in the cost of additive
manufacturing system utilization, material costs, and facilitating
the production of large products. There is also a need for a
standardized model for cost categorization and product quality and
reliability testing.
Whole-building airflow and contaminant transport modeling has a
potentially important role in the development of contaminant
sampling strategies in response to the airborne release of chemical
or biological agents . The effectiveness of these strategies relies
on the ability of the selected sampling locations to adequately
characterize the levels of contamination throughout an exposed
facility to a desired level of confidence in the sampled results.
The Department of Homeland Security has sponsored a series of
multi-agency exercises, during which contamination experiments were
performed to gauge the confidence that could be obtained by various
sampling strategies as well as the effectiveness of various
sampling methods in a real-world setting. These experiments are
very resource intensive and time-consuming, limiting the number of
experiments that can be reasonably performed. Building simulation
can be used to perform virtual experiments that would allow more
tests to be performed under a much larger set of building
operational and environmental configurations. However, in order for
the simulations to be useful, the building models need to provide
realistic results with a high level of confidence. The purpose of
this report is to describe a simulation validation effort based on
measurements of contaminant levels performed during the
aforementioned exercises.
CFAST is a two-zone fire model capable of predicting the
environment in a multi-compartment structure subjected to a fire.
It calculates the time evolving distribution of smoke and fire
gases and the temperature throughout a building during a
user-prescribed fire. This report describes the equations which
constitute the model, the physical basis for these equations, and
an evaluation of the sensitivity and predictive capability of the
model. This report is an assessment of the model following the
outline set forth in ASTM E1355, Standard Guide for Evaluating the
Predictive Capability of Deterministic Fire Models.
This study demonstrates the performance improvement of an
air-to-air roof top unit (RTU) achieved by optimizing an evaporator
s refrigerant circuitry using evolutionary algorithms. The subject
of this study is a unit with a cooling capacity of 7.5 Tons (26.4
kW). The RTU employs two separate refrigerant cycles having
separate compressors, condensers, and thermostatic expansion valves
(TXV) but using a single evaporator slab in which two separate
refrigerant circuits are implemented. We modified the RTU by
replacing the refrigerant-to-air condensers with water cooled
brazed plate heat exchangers in order to facilitate testing.
Performance tests were conducted in a conditioned environmental
chamber in line with AHRI standard 340/360; in order to accomplish
this, we maintained the liquid line saturation pressure and
subcooling from the manufacturer s test data by adjusting the
condenser water flow rate and temperature. We also measured the
in-situ air velocity profile using Particle Image Velocimetry
(PIV), a non-intrusive, laser-based technique. The measurements
showed that the range of air velocities passing through the heat
exchanger varied from 0.5 ms-1 to 3.0 ms-1, with the integrated
average of the measurements being 1.75 ms-1. The PIV data was used
to generate a map of the air flow distribution through the heat
exchanger, which served as the basis for refrigerant circuitry
optimization.
This report presents a computational assessment of the performance
of steel gravity framing systems with single-plate shear (, shear
tab ) connections and composite floor slabs under column loss
scenarios. The computational assessment uses a reduced modeling
approach, while comparisons with detailed model results and
available experimental data are presented to establish confidence
in the reduced models. The reduced modeling approach enables large
multi-bay systems to be analyzed much more efficiently than the
detailed modeling approaches used in previous studies. Both
quasi-static and sudden column loss scenarios are considered, and
an energy-based approximate procedure for analysis of sudden column
loss is adopted, after verification through comparisons with direct
dynamic analyses, further enhancing the efficiency of the reduced
modeling approach. Reduced models are used to investigate the
influence of factors such as bay spacing, slab continuity, and the
mode of connection failure on the collapse resistance of gravity
frame systems. Simple equations for the rotational capacities of
the connections are derived as a function of a few parameters
including the span length and the connection depth. These equations
yield good agreement with computed rotational capacities of
connections both in bare steel assemblies (i.e., no slab) and in
composite floor systems, where composite action leads to reduced
rotational capacities. The reduced models are used to assess the
adequacy of current structural integrity requirements, and based on
the computational results, a new relationship is proposed between
the uniform load intensity and the tie forces required for collapse
prevention
A standard procedure is needed for obtaining smoke toxic potency
data for use in fire hazard and risk analyses. Room fire testing of
finished products is impractical, directing attention to the use of
apparatus that can obtain the needed data quickly and at affordable
cost. This report presents examination of the fourth of a series
bench-scale fire tests to produce data on the yields of toxic
products in both pre-flashover and post-flashover flaming fires.
The apparatus is the ISO 5660-1 / ASTM E 1354 cone calorimeter,
modified to have an enclosure and a gas delivery system allowing
variable oxygen concentration. The test specimens was cut from
finished products that were also burned in room-scale tests: a sofa
made of upholstered cushions on a steel frame, particleboard
bookcases with a laminated finish, and household electric cable.
Initially, the standard test procedure was followed. Subsequent
variation in the procedure included reducing the supplied oxygen
volume fraction to 0.18, 0.16, and 0.14, reducing the incident heat
flux to 25 kW/m2, and reducing the gas flow rate by half. The
yields of CO2 CO, HCl, and HCN were determined. The yields of other
toxicants (NO, NO2, formaldehyde, and acrolein) were below the
detection limits, but volume fractions at the detection limits were
shown to be of limited toxicological importance relative to the
detected toxicants. In general, performing the tests at the reduced
oxygen volume fraction led to small increases on the toxic gas
yields. The exceptions were an increase in the CO yield for the
bookcase at 0.14 oxygen volume fraction. Reducing the incident heat
flux had little effect on the toxic gas yields, other than
increasing variability. Reducing the gas flow rate reduced the
limits of detection by half, but also resulted in reduced gas
yields at lower oxygen volume fractions. In none of the procedure
variations did the CO yield approach the value of 0.2 found in
real-scale post flashover fire tests.
This study examines the energy consumption of automatic ice makers
installed in domestic refrigerators. This study builds upon the
findings of a previous study and examines two refrigerator-freezers
of different configurations, one French-door units with bottom
freezers and one bottom mount unit that uses a twist tray mechanism
to free frozen ice from the icemaker. Ice maker energy consumption
is difficult to measure because they operate on a periodic cycle
which is independent of the compressor cycle used to maintain the
cold temperatures in the domestic refrigerator where it is
installed; therefore methods proposed prior to this study have been
subject to significant truncation error due to partial ice maker or
compressor cycling. The purpose of this study is to define a method
of measuring the energy consumption of automatic ice makers that
will generate a repeatable and reproducible result. Several sets of
test data from these units were analyzed and used to decipher the
energy consumption of automatic ice makers. Through this effort, we
developed a method of test to characterize ice maker energy
consumption which circumvents the inherent problem with its
measurement, truncation error due to incomplete cycling. The
truncation error is avoided by measuring specific parameters with
different sections of data from the same data set. This method was
found to rapidly approach steady state values for the ice maker
energy consumption. We then analyzed data sets from a prior study
and found similar results for the stability of the ice making
energy consumption; that continuous data over only 6 or 7 ice
making cycles are typically sufficient to accurately characterize
the energy consumption.
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