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Modular Aneutronic Fusion Engine

Description: NASA's JUNO mission will arrive at Jupiter in July 2016, after nearly five years in space. Since operational costs tend to rise with mission time, minimizing such times becomes a top priority. We present the conceptual design for a 10MW aneutronic fusion engine with high exhaust velocities that would reduce transit time for a Jupiter mission to eighteen months and enable more challenging exploration missions in the solar system and beyond. __________________________________________________
Date: May 11, 2012
Creator: Pajer, Gary; Razin, Yosef; Paluszek, Michael; Glasser, A. H. & Cohen, Samuel
Partner: UNT Libraries Government Documents Department

Low dose radiation hypersensitivity and clustered DNA damages in human fibroblasts exposed to low dose and dose rate protons or 137CS y-rays

Description: Effective radioprotection for human space travelers hinges upon understanding the individual properties of charged particles. A significant fraction of particle radiation astronauts will encounter in space exploratory missions will come from high energy protons in galactic cosmic radiation (GCR) and/or possible exposures to lower energy proton flux from solar particle events (SPEs). These potential exposures present major concerns for NASA and others, in planning and executing long term space exploratory missions. We recently reported cell survival and transformation (acquisition of anchorage-independent growth in soft agar) frequencies in apparently normal NFF-28 primary human fibroblasts exposed to 0-30 cGy of 50MeV, 100MeV (SPE-like), or 1000 MeV (GCR-like) monoenergetic protons. These were modeled after 1989 SPE energies at an SPE-like low dose-rate (LDR) of 1.65 cGy/min or high dose rate (HDR) of 33.3 cGy/min delivered at the NASA Space Radiation Laboratory (NSRL) at BNL.
Date: May 14, 2013
Creator: Bennett, P. V.; Keszenman, D. J.; Johnson, A. M.; Sutherland, B. M. & Wilson, P. F.
Partner: UNT Libraries Government Documents Department

NASA: Compliance With Cost Limits Cannot Be Verified

Description: Correspondence issued by the General Accounting Office with an abstract that begins "The National Aeronautics and Space Administration's (NASA) authorization act for fiscal year 2000 limits expenditures for space station development to $25 billion and for shuttle launches to $17.7 billion. The act also requires NASA to (1) account for and report amounts obligated to date against the cost limits, (2) identify the amounts needed for future development and completion of the space station, and (3) arrange for GAO to verify the accounting within 60 days after submission of the budget request. Last year, GAO reported that NASA, as part of its fiscal year 2002 budget request, did not comply with the act's requirement to use obligations as its basis for reporting against the cost limits but instead used budget authority. The agency was also unable to provide detailed support for the amounts obligated against the limits for evaluation within the 60 days, but said that it could have provided the information if given more time. After a protracted effort, NASA has acknowledged that its systems cannot provide the data needed to support amounts obligated against the limits. NASA's inability to provide detailed data is due to its lack of a modern, integrated financial management system."
Date: April 10, 2002
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

NASA: Briefing on National Aeronautics and Space Administration's Programs and Associated Activities

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "The National Aeronautics and Space Act of 1958, as amended, established the National Aeronautics and Space Administration (NASA) as the civilian agency that exercises control over U.S. aeronautical and space activities and seeks and encourages the fullest commercial use of space. NASA's activities span a broad range of complex and technical endeavors, from investigating the composition, evaluation, and resources of Mars; to working with international partners to complete and operate the International Space Station; to providing satellite and aircraft observations of Earth for scientific and weather forecasting; to developing new technologies designed to improve air flight safety. The agency currently engages in these endeavors against a backdrop of growing national government fiscal imbalance and budget deficits that are straining all federal agencies' resources. Although NASA's budget represents less than 2 percent of the federal government's discretionary budget, the agency is increasingly being asked to expand its portfolio to support important scientific missions, including the study of climate change. Therefore, it is important that these resources be managed as effectively and efficiently as possible. The National Aeronautics and Space Administration Authorization Act of 2008 (Pub. L. No. 110-422)--directed us to review whether NASA's programs and associated activities with a fiscal year 2009 funding level over $50 million--are duplicative with other activities of the federal government."
Date: October 15, 2009
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: Long-Term Commitment to and Investment in Space Exploration Program Requires More Knowledge

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "The National Aeronautics and Space Administration (NASA) plans to spend nearly $230 billion over the next two decades implementing the Vision for Space Exploration. In January 2006, NASA publicly released its Exploration Systems Architecture Study (ESAS), which is an effort to identify the best architecture and strategy to implement the President's 2004 Vision for Space Exploration (Vision). The cost estimate for implementing the ESAS through fiscal year 2011 exceeds $31 billion. The estimate through fiscal year 2018 is over $122 billion, and the estimate through fiscal year 2025 is nearly $230 billion. These estimates include the architecture, robotic precursor missions, supporting technologies, and funding needed to service the International Space Station (ISS). NASA plans to implement this architecture through a "go as you can afford to pay" approach, wherein lower-priority efforts would be deferred, descoped, or discontinued to allow NASA to stay within its available budget profile. This approach assumes NASA's budget will increase moderately to keep pace with inflation. Given the long-term fiscal imbalances that will challenge the entire federal government now and in the future, it would be prudent for NASA to establish a program that reduces the risk that significant additional funding, beyond moderate increases for inflation, will be required to execute the program. Government leaders will have to make difficult decisions to resolve such challenges, and the debate over the potential cost and the federal government's role in implementing the Vision are emblematic of the challenges the nation will need to resolve in the years ahead. Because of the significance of this investment, competing demands on the federal discretionary budget, and the importance of the success of NASA's exploration program to the future of U.S. human spaceflight, Congress requested that GAO assess (1) the ...
Date: July 17, 2006
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: Significant Challenges Remain for Access, Use, and Sustainment of the International Space Station

Description: Testimony issued by the Government Accountability Office with an abstract that begins "NASA plans to use international partner and new domestic commercial launch vehicles to access, utilize, and sustain the International Space Station from 2012 through 2020. However, the agency faces challenges in transporting cargo and crew to the ISS as well as ensuring the station is fully utilized. NASA’s decision to rely on the new commercial vehicles to transport cargo starting in 2012 and to transport crew starting in 2017 is inherently risky because the vehicles are not yet proven and are experiencing delays in development. Further, NASA does not have agreements in place for international partners to provide cargo services to the ISS beyond 2016. The agency will also face a decision regarding the need to purchase additional seats on the Russian Soyuz vehicle beyond 2016, likely before commercial vehicles have made significant progress in development, given the three-year lead time necessary for acquiring a seat. This decision is further complicated because restrictions prohibit NASA from making certain payments to Russia in connection with the ISS unless the President makes a determination. Further, NASA currently expects to transport all cargo needed by the ISS in 51 flights through 2020, but if international partner agreements and commercial service contracts do not materialize as the agency plans for the years beyond 2016, the situation could lead to a potential cargo shortfall."
Date: March 28, 2012
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: Compliance with Cost Limits

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "Section 202 of the National Aeronautics and Space Administration (NASA) Authorization Act of 2000, Pub. L. No. 106-391, 202, 114 Stat. 1577, 1587 (Oct. 30, 2000) requires that GAO verify NASA's accounting for amounts obligated against established limits for the space station and related space shuttle support. Under the act, obligations are limited to $25 billion for the International Space Station's (ISS) development and $17.7 billion for shuttle launches in connection with the space station's assembly. In the past, we have advised Congressional committees that NASA was unable to provide detailed support for the amounts obligated against the limits. Thus, we could not verify the amounts that NASA reported in its budget requests to Congress."
Date: April 8, 2005
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: Enhanced Use Leasing Program Needs Additional Controls

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "In 2003, the National Aeronautics and Space Administration (NASA) was authorized to demonstrate enhanced use leasing (EUL) at two centers, allowing the agency to retain the proceeds from leasing out underutilized real property and to accept in-kind consideration in lieu of cash for rent. NASA selected Ames Research Center and Kennedy Space Center for the demonstration program. The agency had requested that Congress extend this authority to additional NASA centers during formulation of the NASA Authorization Act of 2005. NASA's request was not granted. Instead, Section 710 of the NASA Authorization Act of 2005 (Public Law 109-155) directed GAO to review NASA's EUL program. We examined (1) the financial impact of the EUL authority on NASA and whether EUL revenue and other financial benefits would have been realized without the authority, (2) NASA's use of the authority and whether the arrangements made under the authority would have been made in the absence of the authority, and (3) what controls are in place to ensure accountability and transparency and to protect the government. The act also directed GAO to report back to the Congress by December 30, 2006. We presented our preliminary findings to Congress in December 2006. Because of Congress's interest in how NASA is implementing its EUL authority, we are enclosing the full briefing that supported that December presentation with this report, along with a summary of our findings and conclusions."
Date: March 1, 2007
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: International Space Station and Shuttle Support Cost Limits

Description: Correspondence issued by the General Accounting Office with an abstract that begins "The National Aeronautics and Space Administration (NASA) Authorization Act for Fiscal Year 2000 set cost limits on the international space station and space shuttle programs. Under the act, NASA may not obligate more than $25 billion for space station development or more than $17.7 billion for shuttle launches in connection with space station assembly. The act also stipulates that for the purpose of calculating launch costs not more than $380 million per launch shall be used. Finally, the act requires that NASA, as part of its annual budget request, update Congress on its progress by (1) accounting for and reporting amounts obligated against the limitations to date, (2) identifying the amount of budget authority requested for the future development and completion of the space station, and (3) arranging for GAO to verify the accounting submitted to Congress within 60 days after the submission of the budget request. NASA did not comply with the act's requirement to use obligations as its basis for reporting against the space station limit but instead used budget authority. In addition, NASA was unable to provide detailed transaction-based support for amounts obligated against the space station and shuttle limits for GAO to evaluate and meet the 60-day reporting requirement. Because NASA lacked support for the actual cost of completed space station elements and subsystems, GAO could not determine whether NASA's costs were reasonable. Also, the act does not require NASA to charge all relevant obligations against the space station and shuttle limits. As a result, NASA's accounting for the limits in its fiscal year 2002 budget request did not include $2.5 billion of related obligations through fiscal year 2000."
Date: August 31, 2001
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

NASA: Compliance with Cost Limits

Description: Correspondence issued by the General Accounting Office with an abstract that begins "Section 202 of the National Aeronautics and Space Administration (NASA) Authorization Act of 2000 (P.L. 106-391) requires that GAO verify NASA's accounting for amounts obligated against established limits for the space station and related space shuttle support. Under the act, obligations are limited to $25 billion for the space station and $17.7 billion for shuttle support."
Date: April 2, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Skylab: The Human Side of a Scientific Mission

Description: This work attempts to focus on the human side of Skylab, America's first space station, from 1973 to 1974. The thesis begins by showing some context for Skylab, especially in light of the Cold War and the “space race” between the United States and the Soviet Union. The development of the station, as well as the astronaut selection process, are traced from the beginnings of NASA. The focus then shifts to changes in NASA from the Apollo missions to Skylab, as well as training, before highlighting the three missions to the station. The work then attempts to show the significance of Skylab by focusing on the myriad of lessons that can be learned from it and applied to future programs.
Date: May 2007
Creator: Johnson, Michael P.
Partner: UNT Libraries

NASA: Ares I and Orion Project Risks and Key Indicators to Measure Progress

Description: Testimony issued by the Government Accountability Office with an abstract that begins "The National Aeronautics and Space Administration (NASA) is in the midst of two new development efforts as part of the Constellation Program--the Ares I Crew Launch Vehicle and the Orion Crew Exploration Vehicle. These projects are critical to the success of the overall program, which will return humans to spaceflight after Space Shuttle retirement in 2010. To reduce the gap in human spaceflight, NASA plans to launch Ares I and Orion in 2015--5 years after the Shuttle's retirement. GAO has issued a number of reports and testimonies that touch on various aspects of NASA's Constellation Program, particularly the development efforts underway for the Orion and Ares I projects. These reports and testimonies have questioned the affordability and overall acquisition strategy for each project. NASA has revised the Orion acquisition strategy and delayed the Ares I preliminary design review based on GAO's recommendations in these reports. In addition, GAO continues to monitor these projects on an ongoing basis at the request of members of Congress. Based on this work, GAO was asked to testify on the types of challenges that NASA faces in developing the Ares I and Orion vehicles and identify the key indicators that decision makers could use to assess risks associated with common trouble spots in development. The information in this testimony is based on work completed in accordance with generally accepted government auditing standards."
Date: April 3, 2008
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: Issues Surrounding the Transition from the Space Shuttle to the Next Generation of Human Space Flight Systems

Description: Testimony issued by the Government Accountability Office with an abstract that begins "On January 14, 2004, the President announced a new Vision for space exploration that directs the National Aeronautics and Space Administration (NASA) to focus its efforts on returning humans to the moon by 2020 in preparation for future, more ambitions missions. Implementing the Vision will require hundreds of billions of dollars and a sustained commitment from multiple administrations and Congresses. Some of the funding for implementing exploration activities is expected to come from funding freed up after the retirement of the Space Shuttle, scheduled for 2010, and projected termination of U.S. participation in the International Space Station by 2016. Congress, while supportive of the effort has voiced concern over the potential gap in human space flight. In the NASA Authorization Act of 2005, Congress stated that it is the policy of the United States to have the capability for human access to space on a continuous basis. NASA has made it a priority to minimize the gap to the extent possible. GAO provides no recommendations in this statement. However, GAO continues to emphasize that given the Nation's fiscal challenges and NASA's past difficulty developing systems within cost, schedule, and performance parameters, it is imperative that the agency adequately manage this transition in a fiscally competent and prudent manner."
Date: March 28, 2007
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: Challenges in Completing and Sustaining the International Space Station

Description: Testimony issued by the Government Accountability Office with an abstract that begins "This testimony discusses the challenges faced by the National Aeronautics and Space Administration (NASA) on the International Space Station (ISS) and the Space Shuttle. NASA is in the midst of one of the most challenging periods in its history. As part of its Vision for Space Exploration, NASA is simultaneously developing a range of new technologies and highly complex systems to support future exploration efforts, completing assembly of the space station, and retiring the space shuttle. This is NASA's biggest transition effort since landing humans on the moon more than 3 decades ago and then initiating the Space Shuttle Program a few years later. Taken together, these efforts create significant challenges in terms of managing investments, launch and other facilities, workforce, international partners, and suppliers. Clearly, any delays or problems in completing and sustaining the space station itself, may well have reverberating effects on NASA's ability to ramp up efforts to develop technologies needed for future exploration or to support other important missions. GAO has undertaken a body of work related to NASA's transition efforts that include NASA's industrial supplier base, its workforce challenges, development of new crew and cargo spacecraft, and NASA's assembly and sustainment activities related to the ISS. This statement focuses on the preliminary results of on-going efforts, as well as other GAO work completed to date. Specifically, it will address the following challenges: (1) executing plans to use the shuttle to complete the ISS; (2) maintenance of the shuttle workforce through retirement of the shuttle; and (3) filling the gap between the shuttle and new NASA-developed vehicles to service the ISS. NASA's ability to overcome these challenges will be critical to ensuring the availability of the International Space Station as a viable research entity ...
Date: July 24, 2007
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: Challenges in Completing and Sustaining the International Space Station

Description: Testimony issued by the Government Accountability Office with an abstract that begins "The International Space Station (ISS), the most complex scientific space project ever attempted, remains incomplete. NASA expects the station's final construction cost will be $31 billion and expects sustainment costs through the station's planned retirement in fiscal year 2016 to total $11 billion. The space shuttle, the only vehicle capable of transporting large segments of the station into orbit, is critical to its completion. NASA plans to complete ISS assembly and retire the shuttle in 2010 in order to pursue a new generation of space flight vehicles, which will not begin to be available until 2015. To provide crew rotation and logistical support during this 5-year gap, NASA plans to rely on spacecraft developed by the commercial sector and other countries. In light of these circumstances, GAO examined the risks and challenges NASA faces in (1) completing assembly of the ISS by 2010 and (2) providing logistics and maintenance to the ISS after 2010. GAO's work to accomplish this included reviewing budget, planning, and other documents from NASA; reviewing NASA officials' testimonies; and interviewing NASA and foreign space program officials."
Date: April 24, 2008
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: Projects Need More Disciplined Oversight and Management to Address Key Challenges

Description: Testimony issued by the Government Accountability Office with an abstract that begins "This testimony discusses the National Aeronautics and Space Administration's (NASA) oversight and management of its major projects. As you know, in 1990, GAO designated NASA's contract management as high risk in view of persistent cost growth and schedule slippage in the majority of its major projects. Since that time, GAO's high-risk work has focused on identifying a number of causal factors, including antiquated financial management systems, poor cost estimating, and undefinitized contracts. Because cost growth and schedule delays persist, this area - now titled acquisition management because of the scope of issues that need to be resolved - remains high risk. To its credit, NASA has recently made a concerted effort to improve its acquisition management. In 2007, NASA developed a comprehensive plan to address systemic weaknesses related to how it manages its acquisitions. The plan specifically seeks to strengthen program/project management, increase accuracy in cost estimating, facilitate monitoring of contractor cost performance, improve agency wide business processes, and improve financial management. While we applaud these efforts our recent work has shown that NASA needs to pay more attention to effective project management. It needs to adopt best practices that focus on closing gaps in knowledge about requirements, technologies, funding, time and other resources before it makes commitments to large-scale programs. For instance, the Mars Science Laboratory, which was already over budget, recently announced a 2-year launch delay. Current estimates suggest that the price of this delay may be $400 million--which drives the current project life-cycle cost estimate to $2.3 billion; up from its initial confirmation estimate of $1.6 billion. Also, in just one year, the development costs of NASA's Glory mission increased by 54 percent, or almost $100 million, because of problems NASA's contractor is having developing ...
Date: March 5, 2009
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: Sound Management and Oversight Key to Addressing Crew Exploration Vehicle Project Risks

Description: Testimony issued by the Government Accountability Office with an abstract that begins "The National Aeronautics and Space Administration (NASA) plans to spend nearly $230 billion over the next two decades implementing the President's Vision for Space Exploration (Vision) plans. In July 2006, GAO issued a report that questioned the program's affordability, and particularly, NASA's acquisition approach for one of the program's major projects--the Crew Exploration Vehicle (CEV). This testimony, which is based upon that report and another recent GAO report evaluating NASA's acquisition policies, highlights GAO's continuing concerns with (1) the affordability of the exploration program; (2) the acquisition approach for the CEV, and; (3) NASA's acquisition policies that lack requirements for projects to proceed with adequate knowledge."
Date: September 28, 2006
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

NASA: Shuttle Fleet's Safe Return to Flight Is Key to Space Station Progress

Description: Testimony issued by the General Accounting Office with an abstract that begins "Since its inception, the International Space Station has experienced numerous problems that have resulted in significant cost growth and assembly schedule slippages. Following the Columbia accident and the subsequent grounding of the shuttle fleet in February 2003, concerns about the future of the space station escalated, as the fleet has been key to the station's assembly and operations. In August 2003, the Columbia Accident Investigation Board drew a causal link between aggressive space station goals--supported by the National Aeronautics and Space Administration's (NASA) current culture--and the accident. Specifically, the Board reported that, in addition to technical failures, Columbia's safety was compromised in part by internal pressures to meet an ambitious launch schedule to achieve certain space station milestones. This testimony discusses the implications of the shuttle fleet's grounding on the space station's schedule and cost, and on the program's partner funding and agreements--findings we reported on in September 2003. The testimony also proposes a framework for providing NASA and the Congress with a means to bring about and assess needed cultural changes across the agency."
Date: October 29, 2003
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

NASA: Key Management and Program Challenges

Description: Testimony issued by the Government Accountability Office with an abstract that begins "The National Aeronautics and Space Administration (NASA) is in the midst of many changes and one of the most challenging periods in its history. The space shuttle is slated to retire this year, the International Space Station nears completion but remains underutilized, and a new means of human space flight is under development. Most recently, the administration has proposed a new direction for NASA. Amid all this potential change, GAO was asked to review the key issues facing NASA. This testimony focuses on four areas: 1) retiring the space shuttle; 2) utilizing and sustaining the International Space Station; 3) continuing difficulty developing large-scale systems, including the next generation of human spaceflight systems; and 4) continuing weaknesses in financial management and information technology systems. In preparing this statement, GAO relied on completed work. To address some of these challenges, GAO has recommended that NASA: provide greater information on shuttle retirement costs to Congress, take actions aimed at more effective use of the station research facilities, develop business cases for acquisition programs, and improve financial and IT management. NASA concurred with GAO's International Space Station recommendations, and has improved some budgeting and management practices in response."
Date: February 3, 2010
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Quantitative Analysis of Clustered DNA Damages Induced by Silicon Beams of Different Kinetic Energy

Description: Humans may b exposed to highly energetic charged particle radiation as a result of medical treatments, occupational activitie or accidental events. In recent years, our increasing presence and burgeoning interest in space exploration beyond low Earth orbit has led to a large increase in the research of the biological effects ofcharged particle radiation typical of that encountered in the space radiation environment. The study of the effects of these types of radiation qualities in terms ofDNA damage induction and repair is fundamental to understand mechanisms both underlying their greater biological effectiveness as we)) as the short and long term risks of health effects such as carcinogenesis, degen rative diseases and premature aging. Charged particle radiation induces a variety of DNA alterations, notably bistranded clustered damages, defined as two or more closely-opposed strand break , oxidized bases or abasic sites within a few helical turns. The induction of such highly complex DNA damage enhances the probability of incorrect or incomplete repair and thus constitutes greater potential for genomic instability, cell death and transformation.
Date: May 14, 2013
Creator: J., Keszenman D.; Keszenman, D.J.; Bennett, P.V.; Sutherland, B.M. & Wilson, P.F.
Partner: UNT Libraries Government Documents Department

Oral History Interview with Alan Lee Briscoe, November 22, 2006

Description: Interview with Alan Lee Briscoe, NASA engineer, as part of the Skylab Oral History Project. The interview includes Briscoe's personal experiences about education at Texas A&M University and South Texas School of Law, joining NASA, working in flight control operations and communications support on the Apollo program, and problem-solving on Skylab missions. Briscoe also speaks about the Skylab "wet workshop," the monotony inherit in Skylab work-shift schedules and efforts to break it, and Skylab's contributions to space exploration.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: November 22, 2006
Creator: Johnson, Michael & Briscoe, Alan Lee
Partner: UNT Oral History Program

Oral History Interview with John Aaron, November 4, 2006

Description: Interview with Alan Lee Briscoe, NASA engineer and manager, as part of the Skylab Oral History Project. The interview includes Aaron's personal experiences about childhood and education, having a career with NASA in mission control, space shuttle and software development, and International Space Station programs. Aaron speaks about his duties on various missions, Skylab's importance to NASA and space exploration, and his perceptions of NASA's working and management culture. The interview includes an appendix with photographs.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: November 4, 2006
Creator: Johnson, Michael & Aaron, John
Partner: UNT Oral History Program

The NAS Parallel Benchmarks

Description: The NAS Parallel Benchmarks (NPB) are a suite of parallel computer performance benchmarks. They were originally developed at the NASA Ames Research Center in 1991 to assess high-end parallel supercomputers. Although they are no longer used as widely as they once were for comparing high-end system performance, they continue to be studied and analyzed a great deal in the high-performance computing community. The acronym 'NAS' originally stood for the Numerical Aeronautical Simulation Program at NASA Ames. The name of this organization was subsequently changed to the Numerical Aerospace Simulation Program, and more recently to the NASA Advanced Supercomputing Center, although the acronym remains 'NAS.' The developers of the original NPB suite were David H. Bailey, Eric Barszcz, John Barton, David Browning, Russell Carter, LeoDagum, Rod Fatoohi, Samuel Fineberg, Paul Frederickson, Thomas Lasinski, Rob Schreiber, Horst Simon, V. Venkatakrishnan and Sisira Weeratunga. The original NAS Parallel Benchmarks consisted of eight individual benchmark problems, each of which focused on some aspect of scientific computing. The principal focus was in computational aerophysics, although most of these benchmarks have much broader relevance, since in a much larger sense they are typical of many real-world scientific computing applications. The NPB suite grew out of the need for a more rational procedure to select new supercomputers for acquisition by NASA. The emergence of commercially available highly parallel computer systems in the late 1980s offered an attractive alternative to parallel vector supercomputers that had been the mainstay of high-end scientific computing. However, the introduction of highly parallel systems was accompanied by a regrettable level of hype, not only on the part of the commercial vendors but even, in some cases, by scientists using the systems. As a result, it was difficult to discern whether the new systems offered any fundamental performance advantage over vector supercomputers, and, if ...
Date: November 15, 2009
Creator: Bailey, David H.
Partner: UNT Libraries Government Documents Department