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West coast RFI survey, volume 1, volume 2 appendix E, volume 3 appendix F, volume 4 appendix G, and volume 5 appendix H
Activities and data reported cover experimental design, mechanization onboard the aircraft, survey operations, quick look and automated data reduction, and a qualitative comparison of survey data with predicted values for the radio frequency survey. The survey was designed to measure amplitude, frequency and time of occurrence of terrestrial emissions in the VHF band during overflights of heavily populated metropolitan areas located on the Pacific Coast of the Continental United States by sensing and recording equipment installed in jet aircraft.
SPAR thermal analysis processors reference manual, system level 16. Volume 1: Program executive. Volume 2: Theory. Volume 3: Demonstration problems. Volume 4: Experimental thermal element capability. Volume 5: Programmer reference
User instructions are given for performing linear and nonlinear steady state and transient thermal analyses with SPAR thermal analysis processors TGEO, SSTA, and TRTA. It is assumed that the user is familiar with basic SPAR operations and basic heat transfer theory.
Pressure-induced volume collapse and structural phase transitions in SrRuO{sub 3}
We report on the low temperature (6 K) structural properties of SrRuO{sub 3} under quasi-hydrostatic pressure studied by synchrotron X-ray powder diffraction in a diamond anvil cell. First principle calculations predict a first-order perovskite (Pv) to post-perovskite (pPv) phase transition at ∼40 GPa accompanied by a 1.9% volume collapse. Our results rule out the occurrence of a pPv phase to 54 GPa. Instead, we find a Pv to monoclinic to triclinic sequence of phase transitions. The monoclinic to triclinic phase transition at ∼38 GPa is accompanied by a 3.5% volume collapse. X-ray absorption spectroscopy indicates that this volume collapse is not accompanied by a change in Ru valence state. Our results should help guide improvements to theoretical treatments of this and other correlated d-electron systems based on density functional theory. - Graphical abstract: Unit cell volume as a function of pressure (T=6 K). Black squares and red circles correspond to Ne and He pressure media, respectively. Blue dashed lines are fit to the data before the volume collapse using a second-order Birch–Murnaghan equation of state excluding (lower curve) and including (upper curve) neutron diffraction data for the low temperature, ambient pressure volume. Dashed lines denote structural phase boundaries. Display Omitted - Highlights: • Crystal structure of SrRuO3 was studied under high pressure up to 54 GPa. • Pv to monoclinic to triclinic sequence of phase transitions was observed. • Transition to triclinic phase at ∼38 GPa is accompanied by a 3.5% volume collapse. • Volume collapse in SrRuO3 is not driven by a change in Ru valence state. • Pv-to-pPv phase transition predicted by DFT at 40 Gpa is not observed up to 54 GPa.
Design Basis Document / Owner’s Technical Specification for Nitrate Salt Systems in CSP Projects: Volume 1 Specifications for Parabolic Trough Projects, Volume 2 - Specifications for Central Receiver Projects, Volume 3 - Narrative
Design Basis Documents / Owner’s Technical Specifications are developed for parabolic trough and central receiver power plants using nitrate salt as the heat transport fluid and the thermal storage medium. The goals were to 1) distill the successful experience with nitrate salt systems from as many commercial projects as possible, 2) provide technical bases for equipment design/selection that an owner can impose on an EPC contractor, 3) compile this information in one location to provide guidance on salt systems that is as broadly applicable to as many projects as possible, and 4) work toward an industry consensus on a Design Basis Document that reflects the lessons learned from earlier commercial projects. The document allows an owner to provide design guidance, and to impose a minimum set of requirements, above and beyond those in the normal Codes and Standards, on an EPC contractor in an effort to avoid a repeat of past mistakes. If successful, this would allow salt systems to achieve the same levels of reliability and availability as commercial parabolic trough plants using diphenyl oxide / biphenyl (i.e., Dowtherm A, Therminol VP-1) as the heat transfer fluid. The report consists of 3 volumes: • Volume 1 - Specifications for Parabolic Trough Projects • Volume 2 - Specifications for Central Receiver Projects • Volume 3 - Narrative Volumes 1 and 2 include discussions of the following topics: • Plant functional requirements for the salt systems • Plant operating states, and transitions between states, for the salt systems • Risk analysis of the principal salt components • Plant requirements for the salt systems to meet the functional and the operating requirements • Type of specification for the principal salt components: functional; or prescriptive • Current state of the art for salt systems. Volume 3 discusses a number of cases in which the salt equipment at commercial parabolic trough and central receiver projects has not met the projected levels of reliability and availability. Possible reasons for the sources of the problems are discussed, as is a range of possible alternate designs that could avoid the known problems.
A Finite-Volume "Shaving" Method for Interfacing NASA/DAO''s Physical Space Statistical Analysis System to the Finite-Volume GCM with a Lagrangian Control-Volume Vertical Coordinate
Toward the development of a finite-volume Data Assimilation System (fvDAS), a consistent finite-volume methodology is developed for interfacing the NASA/DAO's Physical Space Statistical Analysis System (PSAS) to the joint NASA/NCAR finite volume CCM3 (fvCCM3). To take advantage of the Lagrangian control-volume vertical coordinate of the fvCCM3, a novel "shaving" method is applied to the lowest few model layers to reflect the surface pressure changes as implied by the final analysis. Analysis increments (from PSAS) to the upper air variables are then consistently put onto the Lagrangian layers as adjustments to the volume-mean quantities during the analysis cycle. This approach is demonstrated to be superior to the conventional method of using independently computed "tendency terms" for surface pressure and upper air prognostic variables.
Poly-(3)hexylthiophene nanowire networks for versatile fabrication of bulk heterojunctions with increased active volume
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Large-volume diamond cells for neutron diffraction above 90 GPa
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Lunar Science Conference, 2nd, Houston, Tex., January 11-14, 1971, Proceedings. Volume 1 - Mineralogy and petrology. Volume 2 - Chemical and isotope analyses. Volume 3 - Physical properties/Surveyor III
Lunar science - Conference, Houston, January 1971, Volume 1, Mineralogy and petrology, Volume 2, Chemical and isotope analyses, Volume 3, Physical properties/Surveyor 3
Conservative model reduction for finite-volume models
Here, this work proposes a method for model reduction of finite-volume models that guarantees the resulting reduced-order model is conservative, thereby preserving the structure intrinsic to finite-volume discretizations. The proposed reduced-order models associate with optimization problems characterized by a minimum-residual objective function and nonlinear equality constraints that explicitly enforce conservation over subdomains. Conservative Galerkin projection arises from formulating this optimization problem at the time-continuous level, while conservative least-squares Petrov–Galerkin (LSPG) projection associates with a time-discrete formulation. We equip these approaches with hyper-reduction techniques in the case of nonlinear flux and source terms, and also provide approaches for handling infeasibility. In addition, we perform analyses that include deriving conditions under which conservative Galerkin and conservative LSPG are equivalent, as well as deriving a posteriori error bounds. Numerical experiments performed on a parameterized quasi-1D Euler equation demonstrate the ability of the proposed method to ensure not only global conservation, but also significantly lower state-space errors than nonconservative reduced-order models such as standard Galerkin and LSPG projection.
NASA Thesaurus. Volume 1: Hierarchical listing. Volume 2: Access vocabulary. Volume 3: Definitions
There are over 17,500 postable terms and some 4,000 nonpostable terms approved for use in the NASA Scientific and Technical Information Database in the Hierarchical Listing of the NASA Thesaurus. The generic structure is presented for many terms. The broader term and narrower term relationships are shown in an indented fashion that illustrates the generic structure better than the more widely used BT and NT listings. Related terms are generously applied, thus enhancing the usefulness of the Hierarchical Listing. Greater access to the Hierarchical Listing may be achieved with the collateral use of Volume 2 - Access Vocabulary and Volume 3 - Definitions.
Order–disorder transition in nano-rutile TiO 2 anodes: a high capacity low-volume change Li-ion battery material
Li-Intercalation in nano-rutile TiO 2 -anodes induces loss of long-range order with the formation of ∼5 nm layered Li x TiO 2 domains with ∼1 nm columbite-like grain boundaries.
Next-Generation Performance-Based Regulation. Volume 1: Introduction - Global Lessons for Success; Volume 2: Primer - Essential Elements of Design and Implementation; Volume 3: Innovative Examples from Around the World
Performance-based regulations (PBRs) provide a regulatory framework to connect goals, targets, and measures to utility performance or executive compensation. Well-designed PBRs provide incentives for utility performance, benefiting consumers and utility owners alike. This report considers the role of both PBRs and more discrete performance incentive mechanisms (PIMs) in 21st century power sector transformation. Innovative technologies are transforming the way electricity is generated, delivered, and consumed. PBRs have the potential to realign utility, investor, and consumer incentives and mitigate emerging challenges to the utility business model, renewable integration, and even cyber security.The goals of PBRs in the form of multi-year rate plans are in many respects the same in terms of providing reasonably priced and reliable service to customers. However, today's technologies have changed, and there is more emphasis on clean energy. Thus, the pathways and the potential outcomes are different than they were in the 20th century when centralized generator stations and large infrastructure additions dominated the utility landscape. Given unprecedented changes underway in the electricity sector, PBRs - by specifying expectations of utility performance and outcomes for consumers, while staying agnostic to the exact means of delivery - constitute a form of prescient regulation that harnesses disruption. PBRs are one tool in a broader toolbox in the transition toward flexible regulatory and market structures that rewards utilities that adapt or evolve in reaction to market and technology change. PBRs and PIMs have great value for the electric industry when designed well and can be applied to many different situations. How exactly PBR mechanisms are most effectively enacted will vary based on the utility ownership model, institutional arrangements, and a variety of other local factors. PBRs should be tailored to the needs and goals of each jurisdiction, and perhaps each utility, to most effectively achieve the needs of a 21st century power grid in that jurisdiction. Presented in three volumes, this report highlights the lessons learned from their evolving history, explores essential elements of their design and implementation as well as considerations for how they may be best applied, and examines leading examples of PBRs from the United Kingdom, New York, Denmark, Mexico, and South Africa. The full report, 'Next-Generation Performance Based Regulation - Emphasizing Utility Performance to Unleash Power Sector Innovation,' published in September 2017, can be accessed at https://www.nrel.gov/docs/fy17osti/68512.pdf.
Composite materials. Volume 3 - Engineering applications of composites. Volume 4 - Metallic matrix composites. Volume 8 - Structural design and analysis, Part 2
This volume discusses a vaety of applications of both low- and high-cost composite materials in a number of selected engineering fields. The text stresses the use of fiber-reinforced composites, along with interesting material systems used in the electrical and nuclear industries. As to technology transfer, a similarity is noted between many of the reasons responsible for the utilization of composites and those problems requiring urgent solution, such as mechanized fabrication processes and design for production. Features topics include road transportation, rail transportation, civil aircraft, space vehicles, builing industry, chemical plants, and appliances and equipment. The laminate orientation code devised by Air Force materials laboratory is included. Individual items are announced in this issue.
Image Data Processing System (IDAPS) user manual, S-056 experiment. Volume 1: System description. Volume 2: Batch IDAPS. Volume 3: Interactive IDAPS
Image data processing system (IDAPS) developed to satisfy the image processing requirements of the Skylab S-056 experiment is described. The S-056 experiment was designed to obtain high-resolution photographs of the sun in the far ultraviolet, or soft X-ray, portion of the electromagnetic spectrum. Thirty-five thousand photographs were obtained by the three flights of the program; and, faced with such a massive volume of imagery, the designers of the experiment decided to develop a computer-based system which would reduce the image processing workload. The purpose of the IDAPS User Manual is to give the IDAPS user the necessary information and instructions to effectively utilize the system.
CBCT with specification of imaging dose and CNR by anatomical volume of interest
Purpose: A novel method has been developed for volume of interest (VOI) cone-beam CT (CBCT) imaging using a 2.35 MV/Carbon target linac imaging beam line combined with dynamic multileaf collimator sequences. Methods: The authors demonstrate the concept of acquisition of multiple, separate imaging volumes, where volumes can be either completely separated or nested, and are associated with predetermined imaging dose and contrast-to-noise ratio (CNR) characteristics. Two individual MLC sequences were established in the planning system (Eclipse, Varian Medical) to collimate the beam according to a defined inner VOI (e.g., containing a target volume under image guidance) and an outer VOI (e.g., including surrounding landmarks or organs-at-risk). MLC sequences were interleaved as a function of gantry angle to produce a reconstructed CBCT image with nested VOIs. By controlling the ratio of inner-to-outer ratio of MLC segments (and thus Monitor Units) during acquisition, the relative dose and CNR in the two volumes can be controlled. Inner-to-outer ratios of 2:1 to 6:1 were examined. Results: The concept was explored using an anatomical head phantom to assess image quality. A geometric phantom was used to quantify absolute dose and CNR values for the various sequences. The authors found that the dose in the outer VOI decreased by a functional relationship dependent on the inner-to-outer sequence ratio, while the CNR varied by the square root of dose, as expected. Conclusions: In this study the authors demonstrate flexibility in VOI CBCT by tailoring the imaging dose and CNR distribution in separate volumes within the patient anatomy. This would allow for high quality imaging of a target volume for alignment purposes, with simultaneous low dose imaging of the surrounding anatomy (e.g., for coregistration)