Laser Welding for High Reliability High Consequence Applications.
Abstract not provided.
Rodelas, Jeffrey↗
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Laser Welding for High Reliability High Consequence Applications.
Abstract not provided.
Rodelas, Jeffrey↗
Highly reliable high-power superluminescent diodes with three single-mode active channels
We report superluminescent diodes (SLDs) with three ridged active channels, each having a width of 3.5 μm, based on one 'bulk' and two quantum-well heterostructures. At a cw output power greater than 100 mW, the emission spectra of these SLDs possess a quasi-Gaussian shape with centre wavelengths near 840, 860 and 1060 nm and widths about 15, 25 and 40 nm, respectively. In the above operating conditions, the median service life of the SLDs amounted to approximately 50000, 25000 and more than 60000 h, respectively. (lasers)
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
Deep learning for automated defect detection in high-reliability electronic parts.
Abstract not provided.
Donahue, Emily↗
Highly Reliable Multi-Port Smart Inverter Modules for PV-Based Energy Systems
Generally, large electrolytic capacitors (E-caps) are required to decouple the double-line frequency power fluctuation inherent in all single-phase dc-ac or ac-dc converters. These E-caps pose the weak link in the photovoltaic (PV) inverter because they have poor reliability as a result of short life expectancy and higher equivalent series resistance (ESR) which leads to lower system efficiency. In this paper, multiport smart dual-inverter modules are proposed for residential PV inverter systems with balanced outputs to eliminate the requirement of large decoupling capacitors, thus leading to more reliable and highly efficient inverter modules. The balanced dual outputs are controlled in phase quadrature such that the double frequency current is completely eliminated. One phase supports the standalone residential loads, and the other phase interfaces with the grid, which is synchronized to the utility grid. Also, the proposed modular configuration is scalable to accommodate higher power rating by stacking and paralleling multiple modules. Simulation results for the dual-inverter modules rated for 1 kW each are presented to validate the proposed concept. Experimental results from a controller hardware-in-the-loop (CHIL) platform also verify its feasibility.
14 SOLAR ENERGY↗
Sintered tantalum carbide coatings on graphite substrates: Highly reliable protective coatings for bulk and epitaxial growth
Highly reliable low-cost protective coatings have been sought after for use in crucibles and susceptors for bulk and epitaxial film growth processes involving wide bandgap materials. Here, we propose a production technique for ultra-thick (50–200 μmt) tantalum carbide (TaC) protective coatings on graphite substrates, which consists of TaC slurry application and subsequent sintering processes, i.e., a wet ceramic process. Structural analysis of the sintered TaC layers indicated that they have a dense granular structure containing coarse grain with sizes of 10–50 μm. Furthermore, no cracks or pinholes penetrated through the layers, i.e., the TaC layers are highly reliable protective coatings. The analysis also indicated that no plastic deformation occurred during the production process, and the non-textured crystalline orientation of the TaC layers is the origin of their high reliability and durability. The TaC-coated graphite crucibles were tested in an aluminum nitride (AlN) sublimation growth process, which involves extremely corrosive conditions, and demonstrated their practical reliability and durability in the AlN growth process as a TaC-coated graphite. The application of the TaC-coated graphite materials to crucibles and susceptors for use in bulk AlN single crystal growth, bulk silicon carbide (SiC) single crystal growth, chemical vapor deposition of epitaxial SiC films, and metal-organic vapor phase epitaxy of group-III nitrides will lead to further improvements in crystal quality and reduced processing costs.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
Techniques for Achieving High Reliability Operation of the Spallation Neutron Source High Power Radio-Frequency System
The Spallation Neutron Source (SNS) high power radiofrequency (HPRF) system operates with high reliability to support the goals of the SNS user program. In recent operational periods the availability of the HPRF system has exceeded 97 percent while the neutron source availability overall is typically greater than 90 percent. SNS has a unique set of 92 HPRF stations that operate at either 402.5 MHz or 805 MHz with peak output power ranging from 550 kW to 5 MW and average power ranging from 49.5 kW to 450 kW. The HPRF transmitters consist of chassis-mounted power supplies, solid-state amplifiers and other equipment that support the operation of the klystrons that ultimately provide the RF power to the accelerating structures. Management of the operation and maintenance of the HPRF system has increasingly focused on reliability and sustainability in recent years. Techniques for klystron lifetime preservation and optimization of transmitter reliability have been developed and will be described.
Moss, John↗
High-Reliability Systems and the Control of National Security Data and Information
High-reliability systems are characterized by catastrophic implications in the event of failure. These implications can include substantive damage to the environment, social order, and loss of life. Examples of high-reliability systems include nuclear submarines, nuclear reactors, the electric grid, and nuclear weapons. Due to the catastrophic implications of failure, there are heightened awareness and control mechanisms surrounding related data and information. However, defining the difference between data and information is often ambiguous across scholarly disciplines and in United States policy and legislation. For high-reliability systems, the implications of ambiguity between data and information may affect the security of United States interests and even cost lives. For security, data are raw facts or figures without context, while information is the compilation or articulation of data that forms context. Security depends on clarity in the differences between data and information and how to control them. Control is necessary to ensure that data and information are not unintentionally released to foreign governments, the public, or those without need-to-know. A primary concern in the practice of security is the control of data to avoid the unintended conversion to information. Intra-institutionally, this control is highly complex given the amalgam of legacy data systems and the numerous and constantly evolving nature of modern data systems that were not necessarily designed to be integrated. The complexity of this concern is augmented when institutions are part of interinstitutional collaborations or networks of public-private partnerships that share data and information. Additionally, institutions that share data as a function of policy and legislative action— particularly formally integrated data and information system infrastructures—may be at higher security risk. This paper will present an intra-institutional paradigm that utilizes and integrates concepts from numerous disciplines to frame a critical and underspecified practical issue in security—controlling for the unintended conversion of data to information.
45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
High-Reliability Systems and the Control of National Security Data and Information
High-reliability systems are characterized by catastrophic implications in the event of failure. These implications can include substantive damage to the environment, social order, and loss of life. Examples of high-reliability systems include nuclear submarines, nuclear reactors, the electric grid, and nuclear weapons. Due to the catastrophic implications of failure, there are heightened awareness and control mechanisms surrounding related data and information. However, defining the difference between data and information is often ambiguous across scholarly disciplines and in United States policy and legislation. For high-reliability systems, the implications of ambiguity between data and information may affect the security of United States interests and even cost lives. For security, data are raw facts or figures without context, while information is the compilation or articulation of data that forms context. Security depends on clarity in the differences between data and information and how to control them. Control is necessary to ensure that data and information are not unintentionally released to foreign governments, the public, or those without need-to-know. A primary concern in the practice of security is the control of data to avoid the unintended conversion to information. Intra-institutionally, this control is highly complex given the amalgam of legacy data systems and the numerous and constantly evolving nature of modern data systems that were not necessarily designed to be integrated. The complexity of this concern is augmented when institutions are part of inter-institutional collaborations or networks of public-private partnerships that share data and information. Additionally, institutions that share data as a function of policy and legislative action—particularly formally integrated data and information system infrastructures—may be at higher security risk. This paper will present an intra-institutional paradigm that utilizes and integrates concepts from numerous disciplines to frame a critical and underspecified practical issue in security—controlling for the unintended conversion of data to information.
45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
Highly Reliable Organizations in the Onshore Natural Gas Sector: An Assessment of Current Practices, Regulatory Frameworks, and Select Case Studies
This study focuses on onshore natural gas operations and examines the extent to which oil and gas firms have embraced certain organizational characteristics that lead to 'high reliability' - understood here as strong safety and reliability records over extended periods of operation. The key questions that motivated this study include whether onshore oil and gas firms engaged in exploration and production (E&P) and midstream (i.e., natural gas transmission and storage) are implementing practices characteristic of high reliability organizations (HROs) and the extent to which any such practices are being driven by industry innovations and standards and/or regulatory requirements.
29 ENERGY PLANNING, POLICY, AND ECONOMY↗
Effects of Deep Reductions in Energy Storage Costs on Highly Reliable Wind and Solar Electricity Systems.
We use 36 years (1980-2015) of hourly weather data over the contiguous United States (CONUS) to assess the impact of low-cost energy storage on highly reliable electricity systems that use only variable renewable energy (VRE; wind and solar photovoltaics). Even assuming perfect transmission of wind and solar generation aggregated over CONUS, energy storage costs would need to decrease several hundred-fold from current costs (to ~$1/kWh) in fully VRE electricity systems to yield highly reliable electricity without extensive curtailment of VRE generation. The role of energy storage changes from high-cost storage competing with curtailment to fill short-term gaps between VRE generation and hourly demand to near-free storage serving as seasonal storage for VRE resources. Energy storage faces "double penalties" in VRE/storage systems: with increasing capacity, (1) the additional storage is used less frequently and (2) hourly electricity costs would become less volatile, thus reducing price arbitrage opportunities for the additional storage.
14 SOLAR ENERGY↗
Ultra-high reliability wireless communication systems and methods
Systems and methods for ultra-high reliability (UHR) wireless communications systems and methods are disclosed. The disclosed UHR wireless communications systems and methods make the networked components on a communications infrastructure robust to interference caused by unintentional jamming, intermittent connectivity, weather, and physical barriers.
Russell, John J.↗
Ultra-high reliability wireless communication systems and methods
Systems and methods for ultra-high reliability (UHR) wireless communications systems and methods are disclosed. The disclosed UHR wireless communications systems and methods make the networked components on a communications infrastructure robust to interference caused by unintentional jamming, intermittent connectivity, weather, and physical barriers.
Russell, John L.↗
Highly reliable spin-coated titanium dioxide dielectric
Dielectric degradation as low as 0.3 % has been observed for a highly reliable Titanium dioxide (TiO{sub 2}) film after constant voltage stressing (CVS) with – 4 V for 10{sup 5} second at room temperature (300 K). The film was fabricated by sol –gel spin – coating method on a lightly doped p-Si (~10{sup 15} cm{sup −3}) substrate. The equivalent oxide thickness (EOT) is 7 nm with a dielectric constant 33 (at 1 MHz). Metal – Oxide – Semiconductor (MOS) capacitors have been fabricated with an optimum annealing temperature of 800°C for one hour in a preheated furnace. The dielectric degradation is annealing temperature dependent. A degradation of 1.4 %, 1.2 % and 1.1 % has been observed for 400°C, 600°C and 1000°C temperature annealed MOS respectively. The dielectric degradation increases below or above the optimum temperature of annealing.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
High reliable and stable organic field-effect transistor nonvolatile memory with a poly(4-vinyl phenol) charge trapping layer based on a pn-heterojunction active layer
In this letter, we demonstrate a high reliable and stable organic field-effect transistor (OFET) based nonvolatile memory (NVM) with a polymer poly(4-vinyl phenol) (PVP) as the charge trapping layer. In the unipolar OFETs, the inreversible shifts of the turn-on voltage (V{sub on}) and severe degradation of the memory window (ΔV{sub on}) at programming (P) and erasing (E) voltages, respectively, block their application in NVMs. The obstacle is overcome by using a pn-heterojunction as the active layer in the OFET memory, which supplied a holes and electrons accumulating channel at the supplied P and E voltages, respectively. Both holes and electrons transferring from the channels to PVP layer and overwriting the trapped charges with an opposite polarity result in the reliable bidirectional shifts of V{sub on} at P and E voltages, respectively. The heterojunction OFET exhibits excellent nonvolatile memory characteristics, with a large ΔV{sub on} of 8.5 V, desired reading (R) voltage at 0 V, reliable P/R/E/R dynamic endurance over 100 cycles and a long retention time over 10 years.
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
Cognitive Hybrid Radio Waveforms for High-Reliability Secure Wireless Communications, STL-013-19, Year 2
Presentation to be given at the FY 2020 SDRD Annual Meeting, to be held Sept. 23-24, on WebEx. Cognitive Hybrid Radio Waveforms for High-Reliability Secure Wireless Communications, STL-013-19, Year 2
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
Challenges of Interpreting and Applying New IPC-J-STD-001 Cleanliness Standards in High-Reliability Applications
The electronics industry has rapidly and widely embraced the replacement of ROSE testing with an SIR-focused approach to testing for certification of a qualified manufacturing plan. These new cleanliness documentation standards, housed in IPC J-STD-001 Rev. H, have just begun to impact electronics manufacturers as design and production teams work through how to meet them. This research focuses on the particular challenges of applying these new standards in high-reliability product applications, through the lens of interpreting SIR test results and what they mean for process capability, repeatability and diagnosing a need for process changes. The experiments examined a variety of factors that influence SIR results and suggest areas where SIR test plans can be greatly improved.
Capen, William↗
High-reliability passivation of hydrogen-terminated diamond surface by atomic layer deposition of Al{sub 2}O{sub 3}
Although the two-dimensional hole gas (2DHG) of a hydrogen-terminated diamond surface provides a unique p-type conducting layer for high-performance transistors, the conductivity is highly sensitive to its environment. Therefore, the surface must be passivated to preserve the 2DHG, especially at high temperature. We passivated the surface at high temperature (450 °C) without the loss of C-H surface bonds by atomic layer deposition (ALD) and investigated the thermal reliability of the Al{sub 2}O{sub 3} film. As a result, C-H bonds were preserved, and the hole accumulation effect appeared after the Al{sub 2}O{sub 3} deposition by ALD with H{sub 2}O as an oxidant. The sheet resistivity and hole density were almost constant between room temperature and 500 °C by the passivation with thick Al{sub 2}O{sub 3} film thicker than 38 nm deposited by ALD at 450 °C. After the annealing at 550 °C in air The sheet resistivity and hole density were preserved. These results indicate the possibility of high-temperature application of the C-H surface diamond device in air. In the case of lower deposition temperatures, the sheet resistivity increased after air annealing, suggesting an insufficient protection capability of these films. Given the result of sheet resistivity after annealing, the increase in the sheet resistivity of these samples was not greatly significant. However, bubble like patterns were observed in the Al{sub 2}O{sub 3} films formed from 200 to 400 °C by air annealing at 550 °C for 1 h. On the other hand, the patterns were no longer observed at 450 °C deposition. Thus, this 450 °C deposition is the sole solution to enabling power device application, which requires high reliability at high temperatures.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗