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The work performed under this section includes the surface preparation and application of protective floor coatings; furnishing all labor, materials, and equipment necessary to perform all operations in connection with the application required for satisfactory completion in accordance with the standards and practices set forth herein.
Solid oxide fuel cells (SOFCs) are one of the most efficient and environment-friendly devices for electricity generation. One critical challenge of SOFC commercialization is high cell operating temperatures (800°C-1000°C), which lead to high material costs, high performance degradation rates, long start-up and shutdown times, and limited portable applications. Intermediate temperature (600°C-800°C) operation of SOFCs is limited by sluggish electrode reaction kinetics. The objective of this research is to improve intermediate temperature performance of commercially available Ni-YSZ cermet anode supported SOFCs by liquid infiltration of the anode. One effective method to improve kinetics of electrochemical reactions at the anode is to increase the density of reaction sites, which are known as the triple phase boundaries (TPBs). The porous Ni-YSZ cermet anodes were liquid infiltrated with Ni nanoparticles, leading to a four-fold increase in TPB density in the anode. The improved electrochemical performance of the infiltrated cells compared to the uninfiltrated cells highlights the effectiveness of anode infiltration in facilitating improved anode electrochemical reaction kinetics. However, the post-electrochemical testing characterization revealed that Ni nanoparticles were not stable due to Ni coarsening and were mostly isolated indicating that not all of the additional TPBs were fully utilized in electrochemical reactions due to the lack of an electronic pathway between the Ni nanoparticles. In order to improve microstructural stability of the infiltrated Ni nanoparticles, and to fully utilize the added TPBs, co-infiltration of Ni with a mixed ionic and electronic conductor (MIEC) was carried out. Two MIEC materials are chosen based on their chemical stability and conductivity in the anode operating environments; Gd 0.1 Ce 0.9 O 2-δ (GDC), a predominantly an ionic conductor, and La 0.6 Sr 0.3 Ni 0.15 Cr 0.85 O 3-δ (LSNC), a predominantly electronic conductor, and cells were successfully co-infiltrated to form Ni-GDC and Ni-LSNC nanostructures with the MIEC phases connecting the Ni nanoparticles. Stability tests demonstrated that both MIECs inhibited Ni nanoparticle coarsening. Electrochemical studies showed that Ni-GDC is the most effective for improved anode kinetics. A long-term (120 hours) electrochemical test indicated that infiltration of Ni-GDC into Ni-YSZ cermet anode effectively improves overall cell performance at intermediate temperatures and maintains the performance gain for a long period of time.
A portable computerized device for an aircraft control system includes an input system for inputting commands, a device display for displaying information on the computerized device, a processor, a wireless communication module, and a non-transitory computer readable medium comprising computer executable instructions, the computer executable instructions configured to cause the processor to perform a method. The method can include detecting whether the portable computerized device is in a cockpit state such that the portable computerized device is in and/or docked to an aircraft cockpit or if the portable computerized device is in a remote state such that the portable computerized device is not in an aircraft cockpit or is not docked to an aircraft cockpit. If the portable computerized device is determined to be in a remote state, the method includes operating the remote device in a remote mode. If the portable computerized device is determined to be in a cockpit state, the method includes operating the device in a local mode.
Writing applications for high performance computers is a challenging task. Although writing code by hand still offers the best performance, it is extremely costly and often not very portable. The Computer Aided Parallelization Tools (CAPTools) are a toolkit designed to help automate the mapping of sequential FORTRAN scientific applications onto multiprocessors. CAPTools consists of the following major components: an inter-procedural dependence analysis module that incorporates user knowledge; a 'self-propagating' data partitioning module driven via user guidance; an execution control mask generation and optimization module for the user to fine tune parallel processing of individual partitions; a program transformation/restructuring facility for source code clean up and optimization; a set of browsers through which the user interacts with CAPTools at each stage of the parallelization process; and a code generator supporting multiple programming paradigms on various multiprocessors. Besides describing the rationale behind the architecture of CAPTools, the parallelization process is illustrated via case studies involving structured and unstructured meshes. The programming process and the performance of the generated parallel programs are compared against other programming alternatives based on the NAS Parallel Benchmarks, ARC3D and other scientific applications. Based on these results, a discussion on the feasibility of constructing architectural independent parallel applications is presented.
A new direct energy conversion concept called Nuclear Thermionic Avalanche Cell (NTAC) combined with a Metallic Junction Thermoelectric (MJ-TE) generator, both invented and patented by NASA, offers high specific power for portable applications. Estimates based on experimental results suggest superior performance compared to radioisotope thermoelectric generators (RTG) by up to two orders of magnitude for the NTAC and three to four times better for the MJ-TE generator for the same mass. The NTAC technology can use a variety of radioisotopes including nuclear waste to liberate a large number of intra-band(IB), inner shell electrons of atoms (105 C/cm3) by gamma-ray photons (100 keV to MeV). In contrast, conventional power generation has poor specific power because they only utilize the valence band electrons (3C/cm3) of the semiconductor or free electrons (8×103 C/cm3) of the conductor.
Treatment intensity has a profound effect on motor recovery following neurological injury. The use of robotics has potential to automate these labor-intensive therapy procedures that are typically performed by physical therapists. Further, the use of wearable robotics offers an aspect of portability that may allow for rehabilitation outside the clinic. The authors have developed a soft, portable, lightweight upper extremity wearable robotic device to provide motor rehabilitation of patients with affected upper limbs due to traumatic brain injury (TBI). A key feature of the device demonstrated in this paper is the isolation of shoulder and elbow movements necessary for effective rehabilitation interventions. Herein is presented a feasibility study with one subject and demonstration of the device's ability to provide safe, comfortable, and controlled upper extremity movements. Moreover, it is shown that by decoupling shoulder and elbow motions, desired isolated joint actuation can be achieved.
Flexible photovoltaics (PV) represents a promising research field with great potential for wearable, portable, and indoor applications. Significant progress has been made in recent years, with flexible emerging PV reporting power conversion efficiency (PCE) over 24%. Yet, there is a need for a unifying protocol to assess PV performance, compare research results, and evaluate the state- of-the-art achievements in flexible PV. In this paper, a consensus protocol is presented for measuring PCE over 1,000 bending cycles under 1% strain. Moreover, several good practice guidelines are proposed including bending procedures, flexibility testing with and without encapsulation, and ambient conditions during testing (e.g., temperature, humidity, illumination). Notably, the importance of uniform application of bending radius and the testing of parallel and perpendicular orientations of bending axis with respect to the direction of the electric current are emphasized. These recommendations aim to promote consistency in device comparison and allow for better reproducibility.
ENRICO is a coupled application developed under the U.S. Department of Energy's Exascale Computing Project (ECP) targeting the modeling of advanced nuclear reactors. It couples radiation transport with heat and fluid simulation, including the high-fidelity, highresolution Monte-Carlo code Shift and the Computational fluid dynamics code NekRS. NekRS is a highly-performant open-source code for simulation of incompressible and low-Mach fluid flow, heat transfer, and combustion with a particular focus on turbulent flows in complex domains. It is based on rapidly convergent high-order spectral element discretizations that feature minimal numerical dissipation and dispersion. State-of-the-art multilevel preconditioners, efficient high-order time-splitting methods, and runtime-adaptive communication strategies are built on a fast OCCA-based kernel library, libParanumal, to provide scalability and portability across the spectrum of current and future high-performance computing platforms. On Frontier, Nek5000/RS has recently achieved an unprecedented milestone in breaching over 1 billion spectral elements and 350 billion degrees of freedom. Shift has demonstrated the capability to transport upwards of 1 billion particles per second in full core nuclear reactor simulations featuring complete temperature-dependent, continuous-energy physics on Frontier. Shift achieved a weak-scaling efficiency of 97.8% on 8192 nodes of Frontier and calculated 6 reactions in 214,896 fuel pin regions below 1% statistical error yielding first-of-a-kind resolution for a Monte Carlo transport application.
Polymer binders are important components of most battery electrodes, ensuring high performance and long-term durability. Increasing demand for lithium-ion batteries in the automotive, stationary power, and portable electronics industries calls for a greener binder to replace poly(vinylidene difluoride) (PVDF). We evaluate the performance of aqueous solution-processed electrodes prepared with a rigid-rod polymer binder, poly(2,2'-disulfonyl-4,4'-benzidine terephthalamide) (PBDT). The polyamide backbone and double-helical configuration of PBDT give rise to its mechanical strength and rigidity, and its functional nature (H-bonding amides and sulfonates) can provide specific binding with electrode particles. LiFePO 4 electrodes prepared with 3 wt% PBDT show mechanical integrity and cycling stability, achieving over 1000 cycles at 4C rate with negligible capacity decay. These electrodes demonstrate comparable rate performance with their PVDF counterparts while eliminating fluorine from the electrode as well as the organic solvents needed for processing. Furthermore, this study reveals that PBDT holds great potential as a binder for advanced sustainable batteries.
The major goal of this project was to develop an ionization-based detector that could be integrated into the portable gas chromatography systems currently produced by Defiant Technologies. This new detector would allow Defiant to analyze a broader range of analytes and enter new markets. There was also an interest in testing the new ionization source in an ion mobility spectrometer (IMS) that is produced by Sandia National Laboratories. Not only could this eliminate the need for a radioactive material in the IMS, it would offer Defiant the opportunity to add a whole new product line to their chemical analysis systems. Significant progress was made in the development of a thermionic ionization source (TIS) and detector. Using a MEMs heater was an attractive concept, but it proved to be an unfruitful approach because of the fragility of the devices at elevated temperatures. A rugged alternative heater was developed using nichrome wire and alumina tubes. These heaters are simple to make, and, for low quantity production, will be considerably cheaper to construct than MEMs devices. This work has provided a firm basis for follow-on projects. There is now a solid concept for constructing heater elements where, prior to this work, there was only the hope that MEMs heaters would work. In addition, the electrometer that was developed works better than the commercial rack-mounted system that was originally used in this study. Overcoming these two obstacles provides a clear technical approach for product development. There will be follow on efforts at Defiant Technologies to refine the development of the thermal ionization detector. Designs are being made to combine the TIS and electrometer electronics into a single package with a simple-to-replace TIS element. Further work will also focus on integrating this new detector into portable gas chromatography products and testing to optimize the performance.
Experimental design and performance data on carbon dioxide and oxygen control for portable life support system using lithium peroxide
Multimission Interactive Picture Planner, MIP, computer program for scientifically accurate and fast, three-dimensional animation of scenes in deep space. Versatile, reasonably comprehensive, and portable, and runs on microcomputers. New techniques developed to perform rapidly calculations and transformations necessary to animate scenes in scientifically accurate three-dimensional space. Written in FORTRAN 77 code. Primarily designed to handle Voyager, Galileo, and Space Telescope. Adapted to handle other missions.
A miniaturized, lightweight magnetic sector for a focal plane mass spectrograph (Mattauch-Herzog design) has been designed and fabricated by using a new high-energy-product magnet material (Nd-B-Fe alloy) and a high permeability magnet yoke material (V-Co-Fe alloy). The magnetic sector weighs less than 10 kg, has a focal plane of 5.1 cm in length, and covers a nominal mass range of 40-240 amu. Such a magnetic sector, in conjunction with an array detector and a short microbore capillary column, is well suited for the development of a field-portable gas chromatograph-mass spectrometer instrument of high performance.
The Thermal Control Surfaces Experiment (TCSE) was a successful experiment to study the effects of the space environment on thermal control surfaces using in-space optical properties measurements combined with post-flight analyses. The TCSE reflectometer performed well on the LDEF mission demonstrating that a portable compact integrating sphere spectroreflectometer can be built that is rugged and space rated. Since the retrieval of the TCSE package from space, several other instruments have evolved from its pioneering technologies. These are the Optical Properties Monitor (OPM), the Laboratory Portable SpectroReflectometer (LPSR), and the Space Portable SpectroReflectometer (SPSR). These instruments and experiment packages are described.
Multidisciplinary and multi-zonal applications are an important class of applications in the area of Computational Aerosciences. In these codes, two or more distinct parallel programs or copies of a single program are utilized to model a single problem. To support such applications, it is common to use a programming model where a program is divided into several single program multiple data stream (SPMD) applications, each of which solves the equations for a single physical discipline or grid zone. These SPMD applications are then bound together to form a single multidisciplinary or multi-zonal program in which the constituent parts communicate via point-to-point message passing routines. Unfortunately, simple message passing models, like Intel's NX library, only allow point-to-point and global communication within a single system-defined partition. This makes implementation of these applications quite difficult, if not impossible. In this report it is shown that the new Message Passing Interface (MPI) standard is a viable portable library for implementing the message passing portion of multidisciplinary applications. Further, with the extension of a portable loader, fully portable multidisciplinary application programs can be developed. Finally, the performance of MPI is compared to that of some native message passing libraries. This comparison shows that MPI can be implemented to deliver performance commensurate with native message libraries.
Significant progress has been made in hardware and software technologies, as a result the use of efficient standard message passing communication calls in parallel application codes has greatly assisted in reducing execution times. In addition, the introduction of OpenMP, an industrial standard for shared memory programming with directives addresses the issue of portability and also provides a means to deliver respectable performance. In general however, the manual parallelisation of a user's application code using either message passing or directives is still a very costly and error-prone process.
World Wide Web (W3) technologies such as the Hypertext Transfer Protocol (HTTP) and the Java object-oriented programming environment offer a powerful, yet relatively inexpensive, framework for distributed application software development. This paper describes the design of a real-time payload control and monitoring system that was developed with W3 technologies at NASA Ames Research Center. Based on Java Development Toolkit (JDK) 1.1, the system uses an event-driven "publish and subscribe" approach to inter-process communication and graphical user-interface construction. A C Language Integrated Production System (CLIPS) compatible inference engine provides the back-end intelligent data processing capability, while Oracle Relational Database Management System (RDBMS) provides the data management function. Preliminary evaluation shows acceptable performance for some classes of payloads, with Java's portability and multimedia support identified as the most significant benefit.
An investigation was performed to study the potential for radio frequency (RF) power radiated from transmitting Portable Electronic Devices (PEDs) to create an arcing/sparking event within the fuel tank of a large transport aircraft. A survey of RF emissions from typical intentional transmitting PEDs was first performed. Aircraft measurements of RF coupling to the fuel tank and its wiring were also performed to determine the PEDs induced power on the wiring, and the re-radiated power within the fuel tank. Laboratory simulations were conducted to determine the required RF power level for an arcing/sparking event. Data analysis shows large positive safety margins, even with simulated faults on the wiring.