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Water Supply at Los Alamos during 1997

Description: Production of potable municipal water supplies during 1997 totaled about 1,285.9 million gallons from wells in the Guaje, Pajarito, and Otowi well fields. There was no water used from the spring gallery in Water Canyon or from Guaje Reservoir during 1997. About 2.4 million gallons of water from Los Alamos Reservoir was used to irrigate public parks and recreational lands. The total water usage in 1997 was about 1,288.3 million gallons, or about 135 gallons per day per person living in Los Alamos County. Groundwater pumpage was down about 82.2 million gallons in 1997 compared with the pumpage in 1996. Four new replacement wells were drilled and cased in Guaje Canyon between October 1997 and March 1998. These wells are currently being developed and aquifer tests are being performed. A special report summarizing the geological, geophysical, and well construction logs will be issued in the near future for these new wells.
Date: December 1, 1998
Creator: Maes, M. N.; McLin, S. G. & Purtymun, W. D.
Partner: UNT Libraries Government Documents Department

Investigation of excess thyroid cancer incidence in Los Alamos County

Description: Los Alamos County (LAC) is home to the Los Alamos National Laboratory, a U.S. Department of Energy (DOE) nuclear research and design facility. In 1991, the DOE funded the New Mexico Department of Health to conduct a review of cancer incidence rates in LAC in response to citizen concerns over what was perceived as a large excess of brain tumors and a possible relationship to radiological contaminants from the Laboratory. The study found no unusual or alarming pattern in the incidence of brain cancer, however, a fourfold excess of thyroid cancer was observed during the late-1980`s. A rapid review of the medical records for cases diagnosed between 1986 and 1990 failed to demonstrate that the thyroid cancer excess had resulted from enhanced detection. Surveillance activities subsequently undertaken to monitor the trend revealed that the excess persisted into 1993. A feasibility assessment of further studies was made, and ultimately, an investigation was conducted to document the epidemiologic characteristics of the excess in detail and to explore possible causes through a case-series records review. Findings from the investigation are the subject of this report.
Date: April 1, 1996
Creator: Athas, W.F.
Partner: UNT Libraries Government Documents Department

Structural Health Monitoring Studies of the Alamosa Canyon and I-40 Bridges

Description: From 1994 to 1997 internal research grants from Los Alamos National Laboratory's Laboratory Direct Research and Development (LDRD) office were used to fund an effort aimed at studying global vibration-based damage detection methods. To support this work, several field tests of the Alamosa Canyon Bridge have been performed to study various aspects of applying vibration-based damage detection methods to a real world in situ structure. This report summarizes the data that has been collected from the various vibration tests performed on the Alamosa Canyon Bridge, analyses of these data, and the results that have been obtained. Initially, it was the investigators' intent to introduce various types of damage into this bridge and study several vibration-based damage detection methods. The feasibility of continuously monitoring such a structure for the onset of damage was also going to be studied. However, the restrictions that the damage must be relatively benign or repairable made it difficult to take the damage identification portion of the study to completion. Subsequently, this study focused on quantifying the variability in identified modal parameters caused by sources other than damage. These sources include variability in testing procedures, variability in test conditions, and environmental variability. These variabilities must be understood and their influence on identified modal properties quantified before vibration-based damage detection can be applied with unambiguous results. Quantifying the variability in the identified modal parameters led to the development of statistical analysis procedures that can be applied to the experimental modal analysis results. It is the authors' opinion that these statistical analysis procedures represent one of the major contributions of these studies to the vibration-based damage detection field. Another significant contribution that came from this portion of the study was the extension of a strain-energy-based damage detection method originally developed for structures that exhibit beam-bending response to structures that ...
Date: July 1, 2000
Creator: Farrar, Charles R.; Cornwell, Phillip J.; Doebling, Scott W. & Prime, Michael B.
Partner: UNT Libraries Government Documents Department

Los Alamos National Laboratory: Information on Security of Classified Data, Nuclear Material Controls, Nuclear and Worker Safety, and Project Management Weaknesses

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "The Los Alamos National Laboratory (LANL), which is operated by the National Nuclear Security Administration (NNSA), is responsible for, among other things, designing nuclear weapons. Over the past decade, we have documented numerous security, safety, and project management weaknesses at NNSA's nuclear weapons complex, including LANL. In particular, LANL has experienced a series of high-profile security incidents that have drawn attention to the laboratory's inability to account for and control classified information and maintain a safe work environment. In July 2004, LANL's director declared a suspension--or stand-down--of laboratory operations to address immediate concerns, including the loss of classified computer disks. During the stand-down, laboratory teams identified more than 3,400 security and safety issues. As a result of systemic management concerns, and the fact that the laboratory contractor--the University of California--did not adequately address these problems, the Department of Energy (DOE) decided in 2003 to allow other organizations to compete for the management contract at LANL. The University of California, which had been the exclusive management and operating contractor since the 1940s, was replaced in June 2006 by Los Alamos National Security, LLC, (LANS). LANS is a consortium of contractors that includes Bechtel National, Inc.; the University of California; BWX Technologies, Inc.; and the Washington Group International, Inc. In this context, Congress asked us to provide information detailing recent security, safety, and management problems at LANL. We provided Congressional staffs with information on these issues. This report summarizes and formally transmits the information provided to Congressional staffs. As requested, this report provides information on (1) security incidents that compromised or potentially compromised classified information, (2) incidents involving the loss of or failure to properly account for special nuclear material (highly enriched uranium or plutonium) and radiological material, (3) nuclear ...
Date: January 10, 2008
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Publications of LASL research, 1967--1971

Description: This bibiography is a compilation of unclassified publications of work done at the Los Alamos Scientific Laboratory (LASL) for the years 1967 through 1971. Papers published in those years are included regardless of when they were actually written. Publications received too late for inclusion in earlier compilations are also included. Declassification of previously classified reports is considered to constitute publication. All classified issuances are omitted. The bibliography includes LASL reports, papers released as non-LASL reports, journal articles, books, chapters of books, conference papers (whether published separately or as part of conference proceedings issued as books or reports) papers published in congressional hearings, theses, and U. S. patents. Papers are included in the following categories: accelerators, aerospace studies, analytical technology, astrophysics, atomic physics, biology and medicine, chemical kinetics, chemistry, cryogenics, crystallography, engineering and equipment, EPR and NMR studies, equation of state and shock studies, explosives and detonations, fission physics, health and safety, hydrodynamics and radiation transport, instruments, mathematics and computers, mediumenergy physics, metallurgy and ceramics technology, molecular spectroscopy, Moessbauer effect, neutronics and criticality studies, nuclear physics, nuclear safeguards, optics and lasers, organic chemistry, physics, plasma physics, propulsion systems, reactor technology, solid state science, theoretical physics, thermionics, -waste disposal, and miscellaneous. Author, report number, and KWIC indexes are included. (RWR)
Date: September 1, 1973
Creator: Kerr, A. K.
Partner: UNT Libraries Government Documents Department

2003 Los Alamos National Laboratory Annual Illness and Injury Surveillance Report, Revised September 2007

Description: Annual Illness and Injury Surveillance Program report for 2003 for Los Alamos National Lab. The U.S. Department of Energy’s (DOE) commitment to assuring the health and safety of its workers includes the conduct of epidemiologic surveillance activities that provide an early warning system for health problems among workers. The IISP monitors illnesses and health conditions that result in an absence of workdays, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: October 4, 2007
Creator: U.S. Department of Energy, Office of Health, Safety and Security, Office of Illness and Injury Prevention Programs
Partner: UNT Libraries Government Documents Department

A Survey of Some Los Alamos County Canyons for Radioactive Contamination, Spring 1953 to Spring 1955

Description: Abstract: This document is a survey analysis of soil samples from Los Alamos, Pueblo, Bayo, and Mortandad canyons to determine the presence and activities of radioactive contaminants. Also included are the results of analyses of a few samples of grass and of surface water. This survey covers the period from spring 1953 to spring 1955.
Date: April 1956
Creator: Dodd. Aubrey, O.
Partner: UNT Libraries Government Documents Department

Liquid butane filled load for a liner driven Pegasus experiment.

Description: A hydrogen rich, low density liquid, contained within the internal volume of a cylindrical liner, was requested of the Polymers and Coatings Group (MST-7) of the Los Alamos Materials Science Division for one of the last liner driven experiments conducted on the Los Alamos Pegasus facility. The experiment (Fig.1) was a continuation of the Raleigh-Taylor hydrodynamics series of experiments and associated liners that have been described previously.
Date: January 1, 2001
Creator: Salazar, M. A. (Mike A.); Armijo, E. V. (Elfino V.); Anderson, W. E. (Wallace E.); Atchison, W. L. (Walter L.); Bartos, J. J. (Jacob J.); Garcia, F. (Fermin) et al.
Partner: UNT Libraries Government Documents Department

Dynamic load balancing of matrix-vector multiplications on roadrunner compute nodes

Description: Hybrid architectures that combine general purpose processors with accelerators are being adopted in several large-scale systems such as the petaflop Roadrunner supercomputer at Los Alamos. In this system, dual-core Opteron host processors are tightly coupled with PowerXCell 8i processors within each compute node. In this kind of hybrid architecture, an accelerated mode of operation is typically used to offload performance hotspots in the computation to the accelerators. In this paper we explore the suitability of a variant of this acceleration mode in which the performance hotspots are actually shared between the host and the accelerators. To achieve this we have designed a new load balancing algorithm, which is optimized for the Roadrunner compute nodes, to dynamically distribute computation and associated data between the host and the accelerators at runtime. Results are presented using this approach for sparse and dense matrix-vector multiplications that show load-balancing can improve performance by up to 24% over solely using the accelerators.
Date: January 1, 2009
Creator: Sancho Pitarch, Jose Carlos
Partner: UNT Libraries Government Documents Department

DYNAMIC RIGHT-SIZING IN TCP.

Description: With the widespread arrival of bandwidth-intensive applications such as bulk-data transfer, multi-media web streaming and computational grids for high-performance computing, networking performance over the wide-area network has become a critical component in the infrastructure. Tragically, operating systems are still tuned for yesterday's WAN speeds and network applications. As a result, a painstaking process of manually tuning system buffers must be undertaken to make TCP flow-control scale to meet the needs of today's bandwidth-rich networks. Consequently, we propose an operating system technique called dynamic right-sizing that eliminates the need for this manual process. Previous work has also attacked this problem, but with less than complete solutions. Our solution is more efficient, more transparent, and applies to a wider set of applications, including those that require strict flow-control semantics because of performance disparities between the sender and receiver. Keywords--Wide-area networking, TCP, dynamic flow control, computational grid, high-performance networking, auto-tuning
Date: January 1, 2001
Creator: Fisk, M. E. (Mike E. ) & Feng, W. C. (Wu-Chun)
Partner: UNT Libraries Government Documents Department

Packet spacing : an enabling mechanism for delivering multimedia content in computational grids /

Description: Streaming multimedia with UDP has become increasingly popular over distributed systems like the Internet. Scientific applications that stream multimedia include remote computational steering of visualization data and video-on-demand teleconferencing over the Access Grid. However, UDP does not possess a self-regulating, congestion-control mechanism; and most best-efort traflc is served by congestion-controlled TCF! Consequently, UDP steals bandwidth from TCP such that TCP$ows starve for network resources. With the volume of Internet traffic continuing to increase, the perpetuation of UDP-based streaming will cause the Internet to collapse as it did in the mid-1980's due to the use of non-congestion-controlled TCP. To address this problem, we introduce the counterintuitive notion of inter-packet spacing with control feedback to enable UDP-based applications to perform well in the next-generation Internet and computational grids. When compared with traditional UDP-based streaming, we illustrate that our approach can reduce packet loss over SO% without adversely afecting delivered throughput. Keywords: network protocol, multimedia, packet spacing, streaming, TCI: UDlq rate-adjusting congestion control, computational grid, Access Grid.
Date: January 1, 2001
Creator: Feng, A. C. (Annette C.); Feng, W. C. (Wu-Chun) & Belford, Geneva G.
Partner: UNT Libraries Government Documents Department

MAGNET TOOLKIT: DESIGN, IMPLEMENTATION, AND EVALUATION.

Description: The current trend in constructing high-performance computing systems is to connect a large number of machines via a fast interconnect or a large-scale network such as the Internet, This approach relies on the performance of the interconnect (or Internet) to enable Past, large-scale distributed computing. A detailed understanding of the communication traffic is required in order to optimize the operation of entire system. Network researchers traditionally monitor traffic in the network to gain the insight necessary to optimize network operations. Recent work suggests additional insight can be obtained by also monitoring trafflc at the application level. The Monitor for Application-Generated Network Traffic toolkit (MAGNeT) we describe here monitors application trallic patterns In production systems, thus enabling more highly optimized networks and interconnects for the next generation of high performance computing system. Keywords- monitor, measurement, network protocol, traffic characterization, TCP, MAGNet, traces, application-generated traffic, virtual supercomputing, network-aware applications, computational giids, high-perfomiance computing.
Date: January 1, 2001
Creator: Hay, J. R. (Jeffrey R.); Feng, W. C. (Wu-Chun) & Gardner, M. K. (Mark K.)
Partner: UNT Libraries Government Documents Department

Magnetic gauge measurements on the two-stage gun : homogeneous and heterogeneous initiation of high explosives /

Description: One of the reasons for building our gas-driven two-stage gun at Los Alamos was to be able to do shock initiation experiments on high explosives that were too insensitive to initiate with the single-stage gun. In past ARA meetings we have discussed the operation of the gun and the magnetic gauge measurement method. During the past couple of years we have done a number of magnetic gauge experiments on both liquid and solid high explosives. Shock initiation of high explosives depends on the nature of the material - whether it is homogeneous (liquid) or heterogeneous (pressed solid). In the solid explosives, mostly heterogeneous behavior has been measured. In the liquid explosive isopropyl nitrate, classic homogeneous initiation has been measured including the formation of a superdetonation in the shocked liquid. Experiments in both materials are discussed including the particle (mass) velocity profiles at a number of Lagrangian positions in the flow, progress of the shock front as measured by shock tracker gauges, and the position when the reactive wave reaches a detonation condition. The two-stage gun, in conjunction with the multiple magnetic gauging method, has proven very useful for generating new information in initiation experiments. Information from these experiments is of great value to modelers trying to determine the proper reaction rate models to use in simulations of the shock initiation process.
Date: January 1, 2001
Creator: Gustavsen, R. L. (Richard L.); Alcon, R. R. (Robert R.); Davis, L. L. (Lloyd L.) & Sheffield, S. A. (Stephen A.)
Partner: UNT Libraries Government Documents Department