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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 271 records · Page 15

The elements of a space operations system

The Space Shuttle has completed its flight test program and is entering operational service with its fifth flight in November 1982. With the completion of Shuttle development, its entry to operational service, and delivery of additional units into field service, it is timely to initiate development of the next elements of the system. The elements of a Space Operations System are the Shuttle, a Station in low earth orbit, and upper stages for low and high energy orbit delivery. To design these elements properly will require a substantial operations analysis effort to characterize the most effective performance tradeoffs among the discrete elements. The Shuttle establishes a new context for the design and execution of operations in space. The components of the Shuttle, Space Station, and upper stages will need to share technology and components to minimize the cost and complexity of the logistics of ownership and operation.

Loftus, J. P., Jr.↗

Game-Theoretic Approach for Electricity Pricing Between Distribution System Operator and Load Aggregators

Transactive energy has emerged and gained more and more attention in recent years along with smart grid two-way communication technologies. Electricity pricing strategies play a critical role in influencing and shaping the customers’ energy load profile. In this paper, we investigate the electricity pricing strategy between a distribution system operator (DSO) and load aggregators (LAs) by adopting a bi-level Stackelberg game approach. With the purpose of maximizing its own operating revenue as well as better serving its customers, the upper level DSO will determine the price considering how lower level LAs will respond to it. Peak-to-average ratio of the total demand is modeled as a constraint and peak load is penalized at the upper optimization level. Classical backward induction is used to obtain a Nash equilibrium for the formulated bi-level Stackelberg game. Numerical results demonstrate the effectiveness of the proposed game approach in leveraging flexible demand potential to benefit both DSO and LAs.

Chen, Yang↗

A cost-benefit evaluation of the LANDSAT flow-on operational system

Disciplines to benefit from the LANDSAT Follow-on System include agriculture, petroleum and mineral exploration, hydrologic land use, water resources management, forestry, land use planning and monitoring, and soil management. The annual quantified benefits are in the range of 420 to 970 million (FY 1976 dollars). The operational system sized to achieve the quantified benefits involves a single orbiting satellite with a backup satellite in launch readiness. The ground system includes a basic processing system which feeds information to three user systems - one for agriculture, one for hydrologic land use, and a third for all other users. The resulting present worth benefit cost ratio is at least equal to four with a reasonable likelihood of exceeding nine. This benefit cost ratio is evaluated for an infinite time horizon at the discount rate of 10 percent.

Source record↗

Fault-tolerant software - Experiment with the sift operating system

Results are presented of an experiment conducted in the NASA Avionics Integrated Research Laboratory (AIRLAB) to investigate the implementation of fault-tolerant software techniques on fault-tolerant computer architectures, in particular the Software Implemented Fault Tolerance (SIFT) computer. The N-version programming and recovery block techniques were implemented on a portion of the SIFT operating system. The results indicate that, to effectively implement fault-tolerant software design techniques, system requirements will be impacted and suggest that retrofitting fault-tolerant software on existing designs will be inefficient and may require system modification.

Brunelle, J. E.↗

Fault Survivability of Lightweight Operating Systems for exascale

Concern is growing in the High-Performance Computing community regarding the reliability of proposed exascale systems. Current research has shown that the expected reliability of these machines will greatly reduce their scalability. In constrast to current fault tolerance methods whose reliability focus is only the application, this project investigates the benefits integrating reliability mechcanisms in the operating system and runtime, as well as the appli- cation. More specifically, this project has three broad contributions in the field: First, using failure logs from current leadership-class high-performance computing systems, we outline the failures common on these large-scale systems. Second, we describe a novel memory pro- tection mechcanism capable of protecting common observed failures that uses the similarity inherrant in many OS and applications state, thereby reducing overheads. Finally, using an analogy with OS jitter, we develop a highly effecient simulator capable predicting the performance of resilience methods at the scales expected for future extreme-scale systems.

97 MATHEMATICS AND COMPUTING↗

Operating systems in the air transportation environment.

Consideration of the problems facing air transport at present, and to be expected in the future. In the Northeast Corridor these problems involve community acceptance, airway and airport congestion and delays, passenger acceptance, noise reduction, and improvements in low-density short-haul economics. In the development of a superior short-haul operating system, terminal-configured vs cruise-configured vehicles are evaluated. CTOL, STOL, and VTOL aircraft of various types are discussed. In the field of noise abatement, it is shown that flight procedural techniques are capable of supplementing ?quiet engine' technology.

Cherry, G. W.↗

Investigating Operating System Noise in Extreme-Scale High-Performance Computing Systems using Simulation

Hardware/software co-design for future-generation high-performance computing (HPC) systems aims at closing the gap between the peak capabilities of the hardware and the performance realized by applications (application-architecture performance gap). Performance profiling of architectures and applications is a crucial part of this iterative process. The work in this paper focuses on operating system (OS) noise as an additional factor to be considered for co-design. It represents the first step in including OS noise in HPC hardware/software co-design by adding a noise injection feature to an existing simulation-based co-design toolkit. It reuses an existing abstraction for OS noise with frequency (periodic recurrence) and period (duration of each occurrence) to enhance the processor model of the Extreme-scale Simulator (xSim) with synchronized and random OS noise simulation. The results demonstrate this capability by evaluating the impact of OS noise on MPI_Bcast() and MPI_Reduce() in a simulated future-generation HPC system with 2,097,152 compute nodes.

Engelmann, Christian↗

The Anatomy of Software Changes and Bugs in Autonomous Operating System

Cyberphysical systems with autonomous functions are complex pieces of software, consisting of many components, some of which implement autonomous functionality and some may use AI or machine learning algorithms. Software bugs in an autonomous system are of particular concern, as they can have catastrophic consequences. However, detailed studies based on empirical data are rare and therefore these bugs are not well understood. This paper aims to contribute towards filling that gap by investigating the software changes and bugs in Autonomy Operating System (AOS) for Unmanned Aircraft Systems (UAS), which consist of 26 components containing about 103,000 lines of code and having a total of 772 bugfixes. Based on the data extracted from the code repository and semi-structured interviews with the developers of AOS, we explore the differences among autonomous software components, components developed using Model-based Software Engineering, and reuse with respect to change proneness, fault proneness, distribution of bugfixes among AOS components and files of these components, and characteristics of bugs of different AOS components. Our results show that the autonomous components were significantly more change prone (measured in number of commits and code churn) and fault prone (measured in bugfixes per KLoC) than non-autonomous components. The distribution of the locations of bugfixes was skewed, both at component and file level (i.e., a small number of components / files contained the majority of bugs). These evidence-based findings provide important insights to researchers and practitioners alike and can be used to efficiently improve the quality and reliability of autonomous systems.

Katerina Goseva-Popstojanova↗

Future Opportunities and Challenges with Using Demand Response as a Resource in Distribution System Operation and Planning Activities

This scoping study focuses on identifying the ability for current and future demand response opportunities to contribute to distribution system management. To do so, this scoping study will identify the needs of a distribution system to operate efficiently, safely and reliably; summarize both benefits and challenges for the operation of the distribution system with high penetration levels of distributed energy resources; define a suite of services based on those changing operational needs that could be provided by resources; identify existing demand response opportunities sponsored by distribution utilities and/or aggregators of retail customers; assess the extent to which distribution system services can be provided via DR opportunities both in their current form and with alterations to their design; and provide a qualitative assessment of coordination issues that bulk power and distribution system providers of DR opportunities will need to address.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Lessons from Iowa: Development of a 270 Megawatt Compressed Air Energy Storage Project in Midwest Independent System Operator

The Iowa Stored Energy Park was an innovative, 270 Megawatt, $400 million compressed air energy storage (CAES) project proposed for in-service near Des Moines, Iowa, in 2015. After eight years in development the project was terminated because of site geological limitations. However, much was learned in the development process regarding what it takes to do a utility-scale, bulk energy storage facility and coordinate it with regional renewable wind energy resources in an Independent System Operator (ISO) marketplace. Lessons include the costs and long-term economics of a CAES facility compared to conventional natural gas-fired generation alternatives; market, legislative, and contract issues related to enabling energy storage in an ISO market; the importance of due diligence in project management; and community relations and marketing for siting of large energy projects. Although many of the lessons relate to CAES applications in particular, most of the lessons learned are independent of site location or geology, or even the particular energy storage technology involved.

25 ENERGY STORAGE↗

Space station automation and robotics study. Operator-systems interface

This is the final report of a Space Station Automation and Robotics Planning Study, which was a joint project of the Boeing Aerospace Company, Boeing Commercial Airplane Company, and Boeing Computer Services Company. The study is in support of the Advanced Technology Advisory Committee established by NASA in accordance with a mandate by the U.S. Congress. Boeing support complements that provided to the NASA Contractor study team by four aerospace contractors, the Stanford Research Institute (SRI), and the California Space Institute. This study identifies automation and robotics (A&R) technologies that can be advanced by requirements levied by the Space Station Program. The methodology used in the study is to establish functional requirements for the operator system interface (OSI), establish the technologies needed to meet these requirements, and to forecast the availability of these technologies. The OSI would perform path planning, tracking and control, object recognition, fault detection and correction, and plan modifications in connection with extravehicular (EV) robot operations.

Source record↗

Defining Well Clear Separation for Unmanned Aircraft Systems Operating with Noncooperative Aircraft

Detect-and-Avoid (DAA) systems are essential to the safe operations of Unmanned Aircraft Systems, and have the objectives of mitigating collisions with and remaining Well Clear of manned aircraft. This paper analyzes four candidate DAA Well Clear definitions for non-cooperative aircraft using mitigated performance metrics of DAA systems. These DAA Well Clear definitions were proposed in previous work based on their unmitigated collision risk and maneuver initiation range. In this work they are evaluated using safety and operational suitability metrics computed from a large number of representative encounters. Results suggest that although the four candidate DAA Well Clear definitions provide comparable safety, the alerting characteristics give preference for the DAA Well Clear definition without a temporal parameter.

Well Clear↗

Core Community Specifications for Electron Microprobe Operating Systems: Software, Quality Control, and Data Management Issues

Modem electron microprobe systems have become increasingly sophisticated. These systems utilize either UNIX or PC computer systems for measurement, automation, and data reduction. These systems have undergone major improvements in processing, storage, display, and communications, due to increased capabilities of hardware and software. Instrument specifications are typically utilized at the time of purchase and concentrate on hardware performance. The microanalysis community includes analysts, researchers, software developers, and manufacturers, who could benefit from exchange of ideas and the ultimate development of core community specifications (CCS) for hardware and software components of microprobe instrumentation and operating systems.

Fournelle, John↗

Definition of an auxiliary processor dedicated to real-time operating system kernels

In order to increase the efficiency of process control data processing, it is necessary to enhance the productivity of real time high level languages and to automate the task administration, because presently 60 percent or more of the applications are still programmed in assembly languages. This may be achieved by migrating apt functions for the support of process control oriented languages into the hardware, i.e., by new architectures. Whereas numerous high level languages have already been defined or realized, there are no investigations yet on hardware assisted implementation of real time features. The requirements to be fulfilled by languages and operating systems in hard real time environment are summarized. A comparison of the most prominent languages, viz. Ada, HAL/S, LTR, Pearl, as well as the real time extensions of FORTRAN and PL/1, reveals how existing languages meet these demands and which features still need to be incorporated to enable the development of reliable software with predictable program behavior, thus making it possible to carry out a technical safety approval. Accordingly, Pearl proved to be the closest match to the mentioned requirements.

Halang, Wolfgang A.↗

Open Building Operating System: An Open-Source Grid Responsive Control Platform for Buildings

Grid-interactive efficient buildings (GEBs) with flexible loads are a promising method to decarbonize buildings, shift loads during peak hours, and lower energy use and electricity costs. Despite the promising benefits of GEBs, automation systems that manage flexible loads in response to energy prices or other grid signals are still uncommon in small and medium commercial buildings. Recent literature demonstrates such control solutions, but they often rely on custom integrations lacking the tools and drivers needed for scalability. To address these gaps, our team has created a fully open-source software stack capable of integrating heterogeneous flexible building loads and implementing integrated portable control applications called the Open Building Operating System (OpenBOS). The software can be deployed over existing control architecture with a small capital cost. OpenBOS leverages semantic models, which have been the subject of recent investigations to facilitate application portability. The use of semantic data reduces the labor and expense required to deploy and update smart control applications, increasing scalability. In this paper, the semantic modeling schema "Brick" was used, but the proposed approach can also be applied to ASHRAE standard 223P, when released. This paper describes the methodology and software components of OpenBOS and demonstrates its functionality with a rule-based demand flexibility control application configured using a semantic model. This application was tested at a real building in NY that uses a dual-fuel heating system made up of five ductless heat pump mini-splits and a central furnace serving a single zone. The demonstration reduced electricity costs at the site by 27%, demand during a shed event by 49%, and furnace usage by 35%.

24 POWER TRANSMISSION AND DISTRIBUTION↗

An operational system for subject switching between controlled vocabularies

The NASA system of automatically converting sets of terms assigned by Department of Defense indexers to sets of NASA's authorized terms is described. This little-touted system, which has been operating successfully since 1983, matches concepts, rather than words. Subject Switching uses a translation table, known as the Lexical Dictionary, accessed by a program that determines which rules to follow in making the transition from DTIC's to NASA's authorized terms. The authors describe the four phases of development of Subject Switching, changes that have been made, evaluating the system, and benefits. Benefits to NASA include saving indexers' time, the addition of access points for documents indexed, the utilization of other government indexing, and a contribution towards the now-operational NASA, online, interactive, machine aided indexing.

Silvester, June P.↗