States

Eddy sensors for small diameter stainless steel tubes. (open access)

Eddy sensors for small diameter stainless steel tubes.

The goal of this project was to develop non-destructive, minimally disruptive eddy sensors to inspect small diameter stainless steel metal tubes. Modifications to Sandia's Emphasis/EIGER code allowed for the modeling of eddy current bobbin sensors near or around 1/8-inch outer diameter stainless steel tubing. Modeling results indicated that an eddy sensor based on a single axial coil could effectively detect changes in the inner diameter of a stainless steel tubing. Based on the modeling results, sensor coils capable of detecting small changes in the inner diameter of a stainless steel tube were designed, built and tested. The observed sensor response agreed with the results of the modeling and with eddy sensor theory. A separate limited distribution SAND report is being issued demonstrating the application of this sensor.
Date: August 1, 2011
Creator: Skinner, Jack L.; Morales, Alfredo Martin; Grant, J. Brian; Korellis, Henry James; LaFord, Marianne Elizabeth; Van Blarigan, Benjamin et al.
Object Type: Report
System: The UNT Digital Library
LaserFest Celebration (open access)

LaserFest Celebration

LaserFest was the yearlong celebration, during 2010, of the 50th anniversary of the demonstration of the first working laser. The goals of LaserFest were: to highlight the impact of the laser in its manifold commercial, industrial and medical applications, and as a tool for ongoing scientific research; to use the laser as one example that illustrates, more generally, the route from scientific innovation to technological application; to use the laser as a vehicle for outreach, to stimulate interest among students and the public in aspects of physical science; to recognize and honor the pioneers who developed the laser and its many applications; to increase awareness among policymakers of the importance of R&D funding as evidenced by such technology as lasers. One way in which LaserFest sought to meet its goals was to encourage relevant activities at a local level all across the country -- and also abroad -- that would be identified with the larger purposes of the celebration and would carry the LaserFest name. Organizers were encouraged to record and advertise these events through a continually updated web-based calendar. Four projects were explicitly detailed in the proposals: 1) LaserFest on the Road; 2) Videos; 3) Educational material; and 4) …
Date: August 25, 2011
Creator: Chodos, Alan & Rogan, Elizabeth A.
Object Type: Text
System: The UNT Digital Library
Extending the MC-SURE to Denoise Sensor Data Streams (open access)

Extending the MC-SURE to Denoise Sensor Data Streams

None
Date: August 3, 2012
Creator: Ndoye, M. & Kamath, C.
Object Type: Article
System: The UNT Digital Library
PRIDE Surveillance Projects Data Packaging Project Information Package Specification Version 1.1 (open access)

PRIDE Surveillance Projects Data Packaging Project Information Package Specification Version 1.1

Information Package Specification version 1.1 describes an XML document format called an information package that can be used to store information in information management systems and other information archives. An information package consists of package information, the context required to understand and use that information, package metadata that describes the information, and XML signatures that protect the information. The information package described in this specification was designed to store Department of Energy (DOE) and National Nuclear Security Administration (NNSA) information and includes the metadata required for that information: a unique package identifier, information marking that conforms to DOE and NNSA requirements, and access control metadata. It is an implementation of the Open Archival Information System (OAIS) Reference Model archival information package tailored to meet NNSA information storage requirements and designed to be used in the computing environments at the Y-12 National Security Complex and at other NNSA sites.
Date: August 31, 2010
Creator: Kelleher, D. M.; Shipp, R. L. & Mason, J. D.
Object Type: Report
System: The UNT Digital Library
Kauai Island Utility Co-op (KIUC) PV integration study. (open access)

Kauai Island Utility Co-op (KIUC) PV integration study.

This report investigates the effects that increased distributed photovoltaic (PV) generation would have on the Kauai Island Utility Co-op (KIUC) system operating requirements. The study focused on determining reserve requirements needed to mitigate the impact of PV variability on system frequency, and the impact on operating costs. Scenarios of 5-MW, 10-MW, and 15-MW nameplate capacity of PV generation plants distributed across the Kauai Island were considered in this study. The analysis required synthesis of the PV solar resource data and modeling of the KIUC system inertia. Based on the results, some findings and conclusions could be drawn, including that the selection of units identified as marginal resources that are used for load following will change; PV penetration will displace energy generated by existing conventional units, thus reducing overall fuel consumption; PV penetration at any deployment level is not likely to reduce system peak load; and increasing PV penetration has little effect on load-following reserves. The study was performed by EnerNex under contract from Sandia National Laboratories with cooperation from KIUC.
Date: August 1, 2011
Creator: Ellis, Abraham & Mousseau, Tom (Knoxville, TN)
Object Type: Report
System: The UNT Digital Library
Compression Waves and Phase Plots: Simulations (open access)

Compression Waves and Phase Plots: Simulations

Compression wave analysis started nearly 50 years ago with Fowles. Coperthwaite and Williams gave a method that helps identify simple and steady waves. We have been developing a method that gives describes the non-isentropic character of compression waves, in general. One result of that work is a simple analysis tool. Our method helps clearly identify when a compression wave is a simple wave, a steady wave (shock), and when the compression wave is in transition. This affects the analysis of compression wave experiments and the resulting extraction of the high-pressure equation of state.
Date: August 1, 2011
Creator: Orlikowski, D. & Minich, R.
Object Type: Article
System: The UNT Digital Library
REMOVAL OF LEGACY PLUTONIUM MATERIALS FROM SWEDEN (open access)

REMOVAL OF LEGACY PLUTONIUM MATERIALS FROM SWEDEN

U.S. Department of Energy’s National Nuclear Security Administration (NNSA) Office of Global Threat Reduction (GTRI) recently removed legacy plutonium materials from Sweden in collaboration with AB SVAFO, Sweden. This paper details the activities undertaken through the U.S. receiving site (Savannah River Site (SRS)) to support the characterization, stabilization, packaging and removal of legacy plutonium materials from Sweden in 2012. This effort was undertaken as part of GTRI’s Gap Materials Program and culminated with the successful removal of plutonium from Sweden as announced at the 2012 Nuclear Security Summit. The removal and shipment of plutonium materials to the United States was the first of its kind under NNSA’s Global Threat Reduction Initiative. The Environmental Assessment for the U.S. receipt of gap plutonium material was approved in May 2010. Since then, the multi-year process yielded many first time accomplishments associated with plutonium packaging and transport activities including the application of the of DOE-STD-3013 stabilization requirements to treat plutonium materials outside the U.S., the development of an acceptance criteria for receipt of plutonium from a foreign country, the development and application of a versatile process flow sheet for the packaging of legacy plutonium materials, the identification of a plutonium container configuration, the first …
Date: August 18, 2013
Creator: Dunn, Kerry A.; Bellamy, J. Steve; Chandler, Greg T.; Iyer, Natraj C.; Koenig, Rich E.; Leduc, D. et al.
Object Type: Article
System: The UNT Digital Library
NREL Invention Speeds Solar Cell Quality Testing for Industry (Fact Sheet) (open access)

NREL Invention Speeds Solar Cell Quality Testing for Industry (Fact Sheet)

A solid-state optical system, invented by the National Renewable Energy Laboratory (NREL), measures solar cell quantum efficiency (QE) in less than a second, enabling a suite of new capabilities for solar cell manufacturers. QE is a measurement of how cells respond to light across the solar spectrum, but traditional methods for measuring QE had been too slow, limiting its application to small samples pulled from the production line and analyzed in laboratories. NREL's technique, commercialized by Tau Science as the FlashQE(TM) system, uses a solid-state light source, synchronized electronics, and advanced mathematical analysis to parallel-process QE data in a tiny fraction of the time required by the current method, allowing its use on every solar cell passing through a production line.
Date: August 1, 2013
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Bay Ridge Gardens - Mixed-Humid Affordable Multifamily Housing Deep Energy Retrofit (open access)

Bay Ridge Gardens - Mixed-Humid Affordable Multifamily Housing Deep Energy Retrofit

Under this project, Newport Partners (as part of the BA-PIRC research team) evaluated the installation, measured performance, and cost-effectiveness of efficiency upgrade measures for a tenant-in-place DER at the Bay Ridge multifamily (MF) development in Annapolis, Maryland. The design and construction phase of the Bay Ridge project was completed in August 2012. This report summarizes system commissioning, short-term test results, utility bill data analysis, and analysis of real-time data collected over a one-year period after the retrofit was complete. The Bay Ridge project is comprised of a 'base scope' retrofit which was estimated to achieve a 30%+ savings (relative to pre-retrofit) on 186 apartments, and a 'DER scope' which was estimated to achieve 50% savings (relative to pre-retrofit) on a 12-unit building. The base scope was applied to the entire apartment complex, except for one 12-unit building which underwent the DER scope. A wide range of efficiency measures was applied to pursue this savings target for the DER building, including improvements/replacements of mechanical equipment and distribution systems, appliances, lighting and lighting controls, the building envelope, hot water conservation measures, and resident education. The results of this research build upon the current body of knowledge of multifamily retrofits. Towards this end, …
Date: August 1, 2013
Creator: Lyons, J.; Moore, M. & Thompson, M.
Object Type: Report
System: The UNT Digital Library
Establishment of a Hub for the Light Water Reactor Sustainability Online Monitoring Community (open access)

Establishment of a Hub for the Light Water Reactor Sustainability Online Monitoring Community

Implementation of online monitoring and prognostics in existing U.S. nuclear power plants will involve coordinating the efforts of national laboratories, utilities, universities, and private companies. Internet-based collaborative work environments provide necessary communication tools to facilitate interaction between geographically diverse participants. Available technologies were considered, and a collaborative workspace was established at INL as a hub for the light water reactor sustainability online monitoring community.
Date: August 1, 2011
Creator: Lybeck, Nancy J.; Tawfik, Magdy S. & Pham, Binh T.
Object Type: Report
System: The UNT Digital Library
Characterization of Mo/Si multilayer growth on stepped topographies (open access)

Characterization of Mo/Si multilayer growth on stepped topographies

Mo/Si multilayer mirrors with nanoscale bilayer thicknesses have been deposited on stepped substrate topographies, using various deposition angles. The multilayer morphology at the stepedge region was studied by cross section transmission electron microscopy. A transition from a continuous- to columnar layer morphology is observed near the step-edge, as a function of the local angle of incidence of the deposition flux. Taking into account the corresponding kinetics and anisotropy in layer growth, a continuum model has been developed to give a detailed description of the height profiles of the individual continuous layers. Complementary optical characterization of the multilayer system using a microscope operating in the extreme ultraviolet wavelength range, revealed that the influence of the step-edge on the planar multilayer structure is restricted to a region within 300 nm from the step-edge.
Date: August 31, 2011
Creator: van den Boogaard, A. J. R.; Louis, E.; Zoethout, E.; Goldberg, K. A. & Bijkerk, F.
Object Type: Article
System: The UNT Digital Library
Linac Alignment Algorithm: Analysis on 1-to-1 Steering (open access)

Linac Alignment Algorithm: Analysis on 1-to-1 Steering

In a linear accelerator, it is important to achieve a good alignment between all of its components (such as quadrupoles, RF cavities, beam position monitors et al.), in order to better preserve the beam quality during acceleration. After the survey of the main linac components, there are several beam-based alignment (BBA) techniques to be applied, to further optimize the beam trajectory and calculate the corresponding steering magnets strength. Among these techniques the most simple and straightforward one is the one-to-one (1-to-1) steering technique, which steers the beam from quad center to center, and removes the betatron oscillation from quad focusing. For a future linear collider such as the International Linear Collider (ILC), the initial beam emittance is very small in the vertical plane (flat beam with {gamma}{epsilon}{sub y} = 20-40nm), which means the alignment requirement is very tight. In this note, we evaluate the emittance growth with one-to-one correction algorithm employed, both analytically and numerically. Then the ILC main linac accelerator is taken as an example to compare the vertical emittance growth after 1-to-1 steering, both from analytical formulae and multi-particle tracking simulation. It is demonstrated that the estimated emittance growth from the derived formulae agrees well with the results …
Date: August 19, 2011
Creator: Sun, Yipeng & Adolphsen, Chris
Object Type: Report
System: The UNT Digital Library
PRESERVATION OF H2 PRODUCTION ACTIVITY IN NANOPOROUS LATEX COATINGS OF RHODOPSEUDOMONAS PALUSTRIS CGA009 DURING DRY STORAGE AT AMBIENT TEMPERATURES (open access)

PRESERVATION OF H2 PRODUCTION ACTIVITY IN NANOPOROUS LATEX COATINGS OF RHODOPSEUDOMONAS PALUSTRIS CGA009 DURING DRY STORAGE AT AMBIENT TEMPERATURES

To assess the applicability of latex cell coatings as an "off-the-shelf' biocatalyst, the effect of osmoprotectants, temperature, humidity and O{sub 2} on preservation of H{sub 2} production in Rhodopseudomonas palustris coatings was evaluated. Immediately following latex coating coalescence (24 h) and for up to 2 weeks of dry storage, rehydrated coatings containing different osmoprotectants displayed similar rates of H{sub 2} production. Beyond 2 weeks of storage, sorbitol- treated coatings lost all H{sub 2} production activity, whereas considerable H{sub 2} production was still detected in sucrose- and trehalose-stabilized coatings. The relative humidity level at which the coatings were stored had a significant impact on the recovery and subsequent rates of H{sub 2} production. After 4 weeks storage under air at 60% humidity, coatings produced only trace amounts of H{sub 2} (0-0.1% headspace accumulation), whereas those stored at <5% humidity retained 27-53% of their H{sub 2} production activity after 8 weeks of storage. When stored in argon at <5% humidity and room temperature, R. palustris coatings retained full H{sub 2} production activity for 3 months, implicating oxidative damage as a key factor limiting coating storage. Overall, the results demonstrate that biocatalytic latex coatings are an attractive cell immobilization platform for preservation of …
Date: August 27, 2012
Creator: Milliken, C.; Piskorska, M.; Soule, T.; Gosse, J.; Flickinger, M.; Smith, G. et al.
Object Type: Article
System: The UNT Digital Library
Using the X-FEL to photo-pump X-ray laser transitions in He-like Ne (open access)

Using the X-FEL to photo-pump X-ray laser transitions in He-like Ne

Nearly four decades ago H-like and He-like resonantly photo-pumped laser schemes were proposed for producing X-ray lasers. However, demonstrating these schemes in the laboratory has proved to be elusive because of the difficulty of finding a strong resonant pump line. With the advent of the X-ray free electron laser (X-FEL) at the SLAC Linac Coherent Light Source (LCLS) we now have a tunable X-ray laser source that can be used to replace the pump line in previously proposed laser schemes and allow researchers to study the physics and feasibility of resonantly photo-pumped laser schemes. In this paper we use the X-FEL at 1174 eV to photo-pump the singly excited 1s2p state of He-like Ne to the doubly excited 2p3p state and model gain on the 2p3p-2p2s transition at 175 eV and the 2p3p-1s3p transition at 1017 eV. One motivation for studying this scheme is to explore possible quenching of the gain due to strong non-linear coupling effects from the intense X-FEL beam We compare this scheme with photo-pumping the He-like Ne ground state to the 1s3p singly excited state followed by lasing on the 3p-2s and 3d-2p transitions at 158 and 151 eV. Experiments are being planned at LCLS to …
Date: August 30, 2011
Creator: Nilsen, J & Rohringer, N
Object Type: Article
System: The UNT Digital Library
Effects of remediation amendments on vadose zone microorganisms (open access)

Effects of remediation amendments on vadose zone microorganisms

Surfactant-based foam delivery technology has been studied to remediate Hanford 200 area deep vadose zone sediment. However, the surfactants and remediation amendments have an unknown effect on indigenous subsurface microorganisms. Microbial populations are important factors to consider in remediation efforts due to their potential to alter soil geochemistry. This project focuses on measuring microbial metabolic responses to remediation amendments in batch and column studies using Deep Vadose Zone Sediments. Initial studies of the microbes from Hanford 200 area deep vadose zone sediment showed surfactants sodium dodecyl sulfate (SDS) and cocamidopropyl betaine (CAPB) and remediation amendment calcium polysulfide (CPS) had no affect on microbial growth using BiologTM Ecoplates. To move towards a more realistic field analog, soil columns were packed with Hanford 200 Area sediment. Once microbial growth in the column was verified by observing growth of the effluent solution on tryptic soy agar plates, remedial surfactants were injected into the columns, and the resulting metabolic diversity was measured. Results suggest surfactant sodium dodecyl sulfate (SDS) stimulates microbial growth. The soil columns were also visualized using X-ray microtomography to inspect soil packing and possibly probe for evidence of biofilms. Overall, BiologTM Ecoplates provide a rapid assay to predict effects of remediation …
Date: August 10, 2012
Creator: Miller, Hannah M. & Tilton, Fred A.
Object Type: Report
System: The UNT Digital Library
EMSL Geochemistry, Biogeochemistry and Subsurface Science-Science Theme Advisory Panel Meeting (open access)

EMSL Geochemistry, Biogeochemistry and Subsurface Science-Science Theme Advisory Panel Meeting

This report covers the topics of discussion and the recommendations of the panel members. On December 8 and 9, 2010, the Geochemistry, Biogeochemistry, and Subsurface Science (GBSS) Science Theme Advisory Panel (STAP) convened for a more in-depth exploration of the five Science Theme focus areas developed at a similar meeting held in 2009. The goal for the fiscal year (FY) 2011 meeting was to identify potential topical areas for science campaigns, necessary experimental development needs, and scientific members for potential research teams. After a review of the current science in each of the five focus areas, the 2010 STAP discussions successfully led to the identification of one well focused campaign idea in pore-scale modeling and five longer-term potential research campaign ideas that would likely require additional workshops to identify specific research thrusts. These five campaign areas can be grouped into two categories: (1) the application of advanced high-resolution, high mass accuracy experimental techniques to elucidate the interplay between geochemistry and microbial communities in terrestrial ecosystems and (2) coupled computation/experimental investigations of the electron transfer reactions either between mineral surfaces and outer membranes of microbial cells or between the outer and inner membranes of microbial cells.
Date: August 1, 2011
Creator: Brown, Gordon E.; Chaka, Anne; Shuh, David K.; Roden, Eric E.; Werth, Charles J.; Hess, Nancy J. et al.
Object Type: Report
System: The UNT Digital Library
Dispersion in the Presence of Strong Transverse Wakefields (open access)

Dispersion in the Presence of Strong Transverse Wakefields

To minimize emittance growth in a long linac, it is necessary to control the wakefields by correcting the beam orbit excursions. In addition, the particle energy is made to vary along the length of the bunch to introduce a damping, known as the BNS damping, to the beam break-up effect. In this paper, we use a two-particle model to examine the relative magnitudes of the various orbit and dispersion functions involved. The results are applied to calculate the effect of a closed orbit bump and a misaligned structure. It is shown that wake-induced dispersion is an important contribution to the beam dynamics in long linacs with strong wakefields like SLC.
Date: August 12, 2011
Creator: Assmann, Ralph & Chao, Alex
Object Type: Article
System: The UNT Digital Library
Studies of Single Electroweak Bosons at the Tevatron (open access)

Studies of Single Electroweak Bosons at the Tevatron

Tests of the Standard Model with Electroweak Physics have been performed over many decades. In these proceedings, we present several analyses from the Tevatron involving single W or Z bosons. Electroweak (EW) physics has been crucial for discovering and confirming many aspects of the Standard Model (SM). Furthermore, through radiative corrections EW physics allows for indirect views of heavy particles. Indeed the relationship between W boson, top quark, and Higgs boson masses is instrumental in predicting at what mass the Higgs boson may finally be found. In these proceedings, we present several recent analyses from the Tevatron involving single W or Z bosons to test the SM. The Tevatron is a p {bar p} collider at {radical}s = 1.96 TeV located at the Fermi National Accelerator Laboratory. CDF and D0 are its two multi-purpose detectors concentrating on high P{sub T} physics. Both detectors are described in detail elsewhere.
Date: August 1, 2011
Creator: Lyon, Adam L.
Object Type: Article
System: The UNT Digital Library
Emittance and Phase Space Exchange (open access)

Emittance and Phase Space Exchange

Alternative chicane-type beam lines are proposed for exact emittance exchange between horizontal phase space (x; x{prime}) and longitudinal phase space (z; {delta}). Methods to achieve exact phase space exchanges, i.e. mapping x to z, x{prime} to {delta}, z to x and {delta} to x{prime} are suggested. Methods to mitigate the thick-lens effect of the transverse cavity on emittance exchange are discussed. Some applications of the phase space exchanger and the feasibility of an emittance exchange experiment with the proposed chicane-type beam line at SLAC are discussed.
Date: August 19, 2011
Creator: Xiang, Dao & Chao, Alex
Object Type: Article
System: The UNT Digital Library
Assessment of the Current Level of Automation in the Manufacture of Fuel Cell Systems for Combined Heat and Power Applications (open access)

Assessment of the Current Level of Automation in the Manufacture of Fuel Cell Systems for Combined Heat and Power Applications

The U.S. Department of Energy (DOE) is interested in supporting manufacturing research and development (R&D) for fuel cell systems in the 10-1,000 kilowatt (kW) power range relevant to stationary and distributed combined heat and power applications, with the intent to reduce manufacturing costs and increase production throughput. To assist in future decision-making, DOE requested that the National Renewable Energy Laboratory (NREL) provide a baseline understanding of the current levels of adoption of automation in manufacturing processes and flow, as well as of continuous processes. NREL identified and visited or interviewed key manufacturers, universities, and laboratories relevant to the study using a standard questionnaire. The questionnaire covered the current level of vertical integration, the importance of quality control developments for automation, the current level of automation and source of automation design, critical balance of plant issues, potential for continuous cell manufacturing, key manufacturing steps or processes that would benefit from DOE support for manufacturing R&D, the potential for cell or stack design changes to support automation, and the relationship between production volume and decisions on automation.
Date: August 1, 2011
Creator: Ulsh, M.; Wheeler, D. & Protopappas, P.
Object Type: Report
System: The UNT Digital Library
COMPUTATIONAL FLUID DYNAMICS MODELING OF SCALED HANFORD DOUBLE SHELL TANK MIXING - CFD MODELING SENSITIVITY STUDY RESULTS (open access)

COMPUTATIONAL FLUID DYNAMICS MODELING OF SCALED HANFORD DOUBLE SHELL TANK MIXING - CFD MODELING SENSITIVITY STUDY RESULTS

The primary purpose of the tank mixing and sampling demonstration program is to mitigate the technical risks associated with the ability of the Hanford tank farm delivery and celtification systems to measure and deliver a uniformly mixed high-level waste (HLW) feed to the Waste Treatment and Immobilization Plant (WTP) Uniform feed to the WTP is a requirement of 24590-WTP-ICD-MG-01-019, ICD-19 - Interface Control Document for Waste Feed, although the exact definition of uniform is evolving in this context. Computational Fluid Dynamics (CFD) modeling has been used to assist in evaluating scaleup issues, study operational parameters, and predict mixing performance at full-scale.
Date: August 31, 2011
Creator: VL, JACKSON
Object Type: Report
System: The UNT Digital Library
Modified magnetic ground state in NiMn2O4 thin films (open access)

Modified magnetic ground state in NiMn2O4 thin films

We demonstrate the stabilization of a magnetic ground state in epitaxial NiMn2O4 (NMO) thin films not observed in their bulk counterpart. Bulk NMO exhibits a magnetic transition from a paramagnetic phase to a collinear ferrimagnetic moment configuration below 110 K and to a canted moment configuration below 70 K. By contrast, as-grown NMO films exhibit a single magnetic transition at 60 K and annealed films exhibit the magnetic behavior found in bulk. Cation inversion and epitaxial strain are ruled out as possible causes for the new magnetic ground state in the as-grown films. However, a decrease in the octahedral Mn{sup 4+}:Mn{sup 3+} concentration is observed and likely disrupts the double exchange that produces the magnetic state at intermediate temperatures. X-ray magnetic circular dichroism and bulk magnetometry indicate a canted ferrimagnetic state in all samples at low temperature. Together these results suggest that the collinear ferrimagnetic state observed in bulk NMO at intermediate temperatures is suppressed in the as grown NMO thin films due to a decrease in octahedral Mn{sup 4+} while the canted moment ferrimagnetic ordering is preserved below 60 K.
Date: August 3, 2010
Creator: Nelson-Cheeseman, B. B.; Chopdekar, R. V.; Toney, M. F.; Arenholz, E.; Suzuki, Y. & Iwata, J.M.
Object Type: Article
System: The UNT Digital Library
City of Grand Rapids Building Solar Roof Demonstration (open access)

City of Grand Rapids Building Solar Roof Demonstration

Grand Rapids, Michigan is striving to reduce it environmental footprint. The municipal government organization has established environmental sustainability policies with the goal of securing 100% of its energy from renewable sources by 2020. This report describes the process by which the City of Grand Rapids evaluated, selected and installed solar panels on the Water/Environmental Services Building. The solar panels are the first to be placed on a municipal building. Its new power monitoring system provides output data to assess energy efficiency and utilization. It is expected to generate enough clean solar energy to power 25 percent of the building. The benefit to the public includes the economic savings from reduced operational costs for the building; an improved environmentally sustainable area in which to live and work; and increased knowledge about the use of solar energy. It will serve as a model for future energy saving applications.
Date: August 31, 2012
Creator: DeClercq, Mark & Martinez, Imelda
Object Type: Report
System: The UNT Digital Library
A Hierarchical Security Architecture for Cyber-Physical Systems (open access)

A Hierarchical Security Architecture for Cyber-Physical Systems

Security of control systems is becoming a pivotal concern in critical national infrastructures such as the power grid and nuclear plants. In this paper, we adopt a hierarchical viewpoint to these security issues, addressing security concerns at each level and emphasizing a holistic cross-layer philosophy for developing security solutions. We propose a bottom-up framework that establishes a model from the physical and control levels to the supervisory level, incorporating concerns from network and communication levels. We show that the game-theoretical approach can yield cross-layer security strategy solutions to the cyber-physical systems.
Date: August 1, 2011
Creator: Zhu, Quanyan & Basar, Tamer
Object Type: Article
System: The UNT Digital Library