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David G. Holmberg, Joel J. Bender, Michael A. Galler
The BACnet Firewall Router (BFR) is a BACnet router with security firewall functionality. As a firewall it allows network and address filtering plus network and application layer service filtering of BACnet communications according to a security policy
Because most shrinkage-reducing admixtures (SRAs) significantly reduce the surface tension of a cement paste pore solution, they will naturally influence all physical properties and processes that are dependent in some way on surface tension. Such
This manual describes the computer program CONTAM version 2.3 developed by NIST. CONTAM is a multizone indoor air quality and ventilation analysis program designed to help you determine: airflows and pressures infiltration, exfiltration, and room-to-room
A piece of automation equipment such as a robotic crane for steel erection has no intrinsic knowledge of the process it automates. Thus, geometric and spatial information about a component such as a steel member, and the motion sequences that must be
Models of cement paste microstructure that discretize particles on a regular mesh generally must use very fine meshes to resolve the smallest particles. Particularly if the particle size distribution is broad, this leads to undesirably large numbers of
Two 3D Imaging Systems Performance Evaluation Workshops have been held at the National Institute of Standards and Technology (NIST) the first in 2003 and the second in 2005. These workshops were conducted in an effort to determine the need for standard
Economic tools are needed to help the owners and managers of buildings, industrial facilities, and other critical infrastructure to select cost-effective combinations of mitigation strategies that respond to natural and man-made hazards. Economic tools
Stephen J. Treado, Mark A. Kedzierski, Stephanie S. Watson, Kenneth D. Cole
The quality of drinking water has always been a subject of interest. In fact, a stable and secure supply of clean drinking water is a hallmark of modern society. Recently, new concerns have arisen regarding the potential occurrence of intentional or
Quantification of mechanical properties, such as non-linear viscoelastic behavior, for filled elastomers (model nanocomposites) is complicated by the presence of the Mullins effect. This paper examines the potential complications due to the Mullins effect
The design of concrete with specified properties for an application is not a new science, but it has taken on a new meaning with the wide use of special concretes, such as self compacting concrete (SCC). General terms such as flow under its own weight and
This paper compares the hydration characteristics and microstructures of cement pastes with water-to-cement ratios (w/c) of 0.35 and 0.435, cured under saturated and sealed conditions. Degree of hydration is quantified by loss on ignition measurements. The
The measurement of the evolution of mechanical characteristics during the setting period of concrete is needed to control the schedule of construction (pumping, placement, finishing and saw-cutting). This evolution is affected by the compatibility (or
Aaron M. Forster, Stephanie S. Watson, Laura Johnson, Li Piin Sung
Inorganic particles, introduced into networked or glassy polymer films, have been used to increase the stiffness of films as a function of pigment loading. Latex films often contain inorganic pigments to increase the opaqueness of the film and to act as UV
Kenneth A. Snyder, Raymond D. Mountain, Antonio Faraone
A computational toolkit is being developed for studying materials relevant to portland cement hydration. The toolkit will eventually include both a materials database and a collection of computational tools for constructing atomic-scale models, of both
This paper investigates the effect that oil concentration had on the boiling performance of an R123/paraffinic mineral oil mixture on a roughened, horizontal flat surface. For all compositions, the lubricant caused a heat transfer degradation relative to
William V. Payne, Piotr A. Domanski, Minsung Kim, Christian Hermes
System behavior of a R410A residential unitary split heat pump system operating in the cooling mode was investigated. Seven artificial faults were implemented: compressor/reversing valve leakage, improper outdoor air flow, improper indoor air flow, liquid
Minsung Kim, William V. Payne, Piotr A. Domanski, Christian Hermes
System behavior of a R410A residential unitary split heat pump system was investigated. The system was operated in cooling mode and used a thermostatic expansion valve (TXV) as the refrigerant expansion device. Seven artificial faults were tested
William M. Pitts, A V. Murthy, J L. Deris, J R. Filtz, K Nygard, D Smith, I Wetterlund
Total heat flux gauges are widely employed in fire research and fire testing laboratories. Several fire laboratories have developed systems for calibrating these gauges. There are major differences between these calibration facilities, and prior to this
This investigation compares the Seasonal Energy Efficiency Ratio (SEER) ratings of independent coil manufacturers (ICMs) and original equipment manufacturers (OEMs) to determine the distribution of mixed system SEER ratings provided by ICMs and OEMs. ICMs
The percolation state of the capillary porosity in a hydrating cement paste has a large influence both on transport properties and on durability performance. Percolation can be examined both experimentally, using low temperature calorimetry (LTC) for