NSSDC Conference on Mass Storage Systems and Technologies for Space and Earth Science Applications, volume 1

Papers and viewgraphs from the conference are presented. This conference served as a broad forum for the discussion of a number of important issues in the field of mass storage systems. Topics include magnetic disk and tape technologies, optical disks and tape, software storage and file management systems, and experiences with the use of a large, distributed storage system. The technical presentations describe, among other things, integrated mass storage systems that are expected to be available commercially. Also included is a series of presentations from Federal Government organizations and research institutions covering their mass storage requirements for the 1990's

Third International Symposium on Space Mission Operations and Ground Data Systems, part 1

Under the theme of 'Opportunities in Ground Data Systems for High Efficiency Operations of Space Missions,' the SpaceOps '94 symposium included presentations of more than 150 technical papers spanning five topic areas: Mission Management, Operations, Data Management, System Development, and Systems Engineering. The papers focus on improvements in the efficiency, effectiveness, productivity, and quality of data acquisition, ground systems, and mission operations. New technology, techniques, methods, and human systems are discussed. Accomplishments are also reported in the application of information systems to improve data retrieval, reporting, and archiving; the management of human factors; the use of telescience and teleoperations; and the design and implementation of logistics support for mission operations

Music 2025 : The Music Data Dilemma: issues facing the music industry in improving data management

© Crown Copyright 2019Music 2025ʼ investigates the infrastructure issues around the management of digital data in an increasingly stream driven industry. The findings are the culmination of over 50 interviews with high profile music industry representatives across the sector and reflects key issues as well as areas of consensus and contrasting views. The findings reveal whilst there are great examples of data initiatives across the value chain, there are opportunities to improve efficiency and interoperability

Nation-State Attackers and their Effects on Computer Security

Nation-state intelligence agencies have long attempted to operate in secret, but recent revelations have drawn the attention of security researchers as well as the general public to their operations. The scale, aggressiveness, and untargeted nature of many of these now public operations were not only alarming, but also baffling as many were thought impossible or at best infeasible at scale. The security community has since made many efforts to protect end-users by identifying, analyzing, and mitigating these now known operations. While much-needed, the security community's response has largely been reactionary to the oracled existence of vulnerabilities and the disclosure of specific operations. Nation-State Attackers, however, are dynamic, forward-thinking, and surprisingly agile adversaries who do not rest on their laurels and are continually advancing their efforts to obtain information. Without the ability to conceptualize their actions, understand their perspective, or account for their presence, the security community's advances will become antiquated and unable to defend against the progress of Nation-State Attackers. In this work, we present and discuss a model of Nation-State Attackers that can be used to represent their attributes, behavior patterns, and world view. We use this representation of Nation-State Attackers to show that real-world threat models do not account for such highly privileged attackers, to identify and support technical explanations of known but ambiguous operations, and to identify and analyze vulnerabilities in current systems that are favorable to Nation-State Attackers.PHDComputer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/143907/1/aaspring_1.pd

Temporal contrast-dependent modeling of laser-driven solids: studying femtosecond-nanometer interactions and probing

Establishing precise control over the unique beam parameters of laser-accelerated ions from relativistic ultra-short pulse laser-solid interactions has been a major goal for the past 20 years. While the spatio-temporal coupling of laser-pulse and target parameters create transient phenomena at femtosecond-nanometer scales that are decisive for the acceleration performance, these scales have also largely been inaccessible to experimental observation. Computer simulations of laser-driven plasmas provide valuable insight into the physics at play. Nevertheless, predictive capabilities are still lacking due to the massive computational cost to perform these in 3D at high resolution for extended simulation times. This thesis investigates the optimal acceleration of protons from ultra-thin foils following the interaction with an ultra-short ultra-high intensity laser pulse, including realistic contrast conditions up to a picosecond before the main pulse. Advanced ionization methods implemented into the highly scalable, open-source particle-in-cell code PIConGPU enabled this study. Supporting two experimental campaigns, the new methods led to a deeper understanding of the physics of Laser-Wake eld acceleration and Colloidal Crystal melting, respectively, for they now allowed to explain experimental observations with simulated ionization- and plasma dynamics. Subsequently, explorative 3D3V simulations of enhanced laser-ion acceleration were performed on the Swiss supercomputer Piz Daint. There, the inclusion of realistic laser contrast conditions altered the intra-pulse dynamics of the acceleration process significantly. Contrary to a perfect Gaussian pulse, a better spatio-temporal overlap of the protons with the electron sheath origin allowed for full exploitation of the accelerating potential, leading to higher maximum energies. Adapting well-known analytic models allowed to match the results qualitatively and, in chosen cases, quantitatively. However, despite complex 3D plasma dynamics not being reflected within the 1D models, the upper limit of ion acceleration performance within the TNSA scenario can be predicted remarkably well. Radiation signatures obtained from synthetic diagnostics of electrons, protons, and bremsstrahlung photons show that the target state at maximum laser intensity is encoded, previewing how experiments may gain insight into this previously unobservable time frame. Furthermore, as X-ray Free Electron Laser facilities have only recently begun to allow observations at femtosecond-nanometer scales, benchmarking the physics models for solid-density plasma simulations is now in reach. Finally, this thesis presents the first start-to-end simulations of optical-pump, X-ray-probe laser-solid interactions with the photon scattering code ParaTAXIS. The associated PIC simulations guided the planning and execution of an LCLS experiment, demonstrating the first observation of solid-density plasma distribution driven by near-relativistic short-pulse laser pulses at femtosecond-nanometer resolution.Die Erlangung präziser Kontrolle über die einzigartigen Strahlparameter von laserbeschleunigten Ionen aus relativistischen Ultrakurzpuls-Laser-Festkörper-Wechselwirkungen ist ein wesentliches Ziel der letzten 20 Jahre. Während die räumlich-zeitliche Kopplung von Laserpuls und Targetparametern transiente Phänomene auf Femtosekunden- und Nanometerskalen erzeugt, die für den Beschleunigungsprozess entscheidend sind, waren diese Skalen der experimentellen Beobachtung bisher weitgehend unzugänglich. Computersimulationen von lasergetriebenen Plasmen liefern dabei wertvolle Einblicke in die zugrunde liegende Physik. Dennoch mangelt es noch an Vorhersagemöglichkeiten aufgrund des massiven Rechenaufwands, um Parameterstudien in 3D mit hoher Auflösung für längere Simulationszeiten durchzuführen. In dieser Arbeit wird die optimale Beschleunigung von Protonen aus ultradünnen Folien nach der Wechselwirkung mit einem ultrakurzen Ultrahochintensitäts-Laserpuls unter Einbeziehung realistischer Kontrastbedingungen bis zu einer Pikosekunde vor dem Hauptpuls untersucht. Hierbei ermöglichen neu implementierte fortschrittliche Ionisierungsmethoden für den hoch skalierbaren, quelloffenen Partikel-in-Zelle-Code PIConGPU von nun an Studien dieser Art. Bei der Unterstützung zweier Experimentalkampagnen führten diese Methoden zu einem tieferen Verständnis der Laser-Wake eld-Beschleunigung bzw. des Schmelzens kolloidaler Kristalle, da nun experimentelle Beobachtungen mit simulierter Ionisations- und Plasmadynamik erklärt werden konnten. Im Anschluss werden explorative 3D3V Simulationen verbesserter Laser-Ionen-Beschleunigung vorgestellt, die auf dem Schweizer Supercomputer Piz Daint durchgeführt wurden. Dabei veränderte die Einbeziehung realistischer Laserkontrastbedingungen die Intrapulsdynamik des Beschleunigungsprozesses signifikant. Im Gegensatz zu einem perfekten Gauß-Puls erlaubte eine bessere räumlich-zeitliche Überlappung der Protonen mit dem Ursprung der Elektronenwolke die volle Ausnutzung des Beschleunigungspotentials, was zu höheren maximalen Energien führte. Die Adaptation bekannter analytischer Modelle erlaubte es, die Ergebnisse qualitativ und in ausgewählten Fällen auch quantitativ zu bestätigen. Trotz der in den 1D-Modellen nicht abgebildeten komplexen 3D-Plasmadynamik zeigt die Vorhersage erstaunlich gut das obere Limit der erreichbaren Ionen-Energien im TNSA Szenario. Strahlungssignaturen, die aus synthethischen Diagnostiken von Elektronen, Protonen und Bremsstrahlungsphotonen gewonnen wurden, zeigen, dass der Target-Zustand bei maximaler Laserintensität einkodiert ist, was einen Ausblick darauf gibt, wie Experimente Einblicke in dieses bisher unbeobachtbare Zeitfenster gewinnen können. Mit neuen Freie-Elektronen-Röntgenlasern sind Beobachtungen auf Femtosekunden-Nanometerskalen endlich zugänglich geworden. Damit liegt ein Benchmarking der physikalischen Modelle für Plasmasimulationen bei Festkörperdichte nun in Reichweite, aber Experimente sind immer noch selten, komplex, und schwer zu interpretieren. Zuletzt werden daher in dieser Arbeit die ersten Start-zu-End-Simulationen der Pump-Probe Wechselwirkungen von optischem sowie Röntgenlaser mit Festkörpern mittels des Photonenstreu-Codes ParaTAXIS vorgestellt. Darüber hinaus dienten die zugehörigen PIC-Simulationen als Grundlage für die Planung und Durchführung eines LCLS-Experiments zur erstmaligen Beobachtung einer durch nah-relativistische Kurzpuls-Laserpulse getriebenen Festkörper-Plasma-Dichte, dessen Auflösungsbereich gleichzeitig bis auf Femtosekunden und Nanometer vordrang

Temporal contrast-dependent modeling of laser-driven solids - studying femtosecond-nanometer interactions and probing

Establishing precise control over the unique beam parameters of laser-accelerated ions from relativistic ultra-short pulse laser-solid interactions has been a major goal for the past 20 years. While the spatio-temporal coupling of laser-pulse and target parameters create transient phenomena at femtosecond-nanometer scales that are decisive for the acceleration performance, these scales have also largely been inaccessible to experimental observation. Computer simulations of laser-driven plasmas provide valuable insight into the physics at play. Nevertheless, predictive capabilities are still lacking due to the massive computational cost to perform these in 3D at high resolution for extended simulation times. This thesis investigates the optimal acceleration of protons from ultra-thin foils following the interaction with an ultra-short ultra-high intensity laser pulse, including realistic contrast conditions up to a picosecond before the main pulse. Advanced ionization methods implemented into the highly scalable, open-source particle-in-cell code PIConGPU enabled this study. Supporting two experimental campaigns, the new methods led to a deeper understanding of the physics of Laser-Wakefield acceleration and Colloidal Crystal melting, respectively, for they now allowed to explain experimental observations with simulated ionization- and plasma dynamics. Subsequently, explorative 3D3V simulations of enhanced laser-ion acceleration were performed on the Swiss supercomputer Piz Daint. There, the inclusion of realistic laser contrast conditions altered the intra-pulse dynamics of the acceleration process significantly. Contrary to a perfect Gaussian pulse, a better spatio-temporal overlap of the protons with the electron sheath origin allowed for full exploitation of the accelerating potential, leading to higher maximum energies. Adapting well-known analytic models allowed to match the results qualitatively and, in chosen cases, quantitatively. However, despite complex 3D plasma dynamics not being reflected within the 1D models, the upper limit of ion acceleration performance within the TNSA scenario can be predicted remarkably well. Radiation signatures obtained from synthetic diagnostics of electrons, protons, and bremsstrahlung photons show that the target state at maximum laser intensity is encoded, previewing how experiments may gain insight into this previously unobservable time frame. Furthermore, as X-ray Free Electron Laser facilities have only recently begun to allow observations at femtosecond-nanometer scales, benchmarking the physics models for solid-density plasma simulations is now in reach. Finally, this thesis presents the first start-to-end simulations of optical-pump, X-ray-probe laser-solid interactions with the photon scattering code ParaTAXIS. The associated PIC simulations guided the planning and execution of an LCLS experiment, demonstrating the first observation of solid-density plasma distribution driven by near-relativistic short-pulse laser pulses at femtosecond-nanometer resolution

Operating system support for warehouse-scale computing

Modern applications are increasingly backed by large-scale data centres. Systems software in these data centre environments, however, faces substantial challenges: the lack of uniform resource abstractions makes sharing and resource management inefficient, infrastructure software lacks end-to-end access control mechanisms, and work placement ignores the effects of hardware heterogeneity and workload interference. In this dissertation, I argue that uniform, clean-slate operating system (OS) abstractions designed to support distributed systems can make data centres more efficient and secure. I present a novel distributed operating system for data centres, focusing on two OS components: the abstractions for resource naming, management and protection, and the scheduling of work to compute resources. First, I introduce a reference model for a decentralised, distributed data centre OS, based on pervasive distributed objects and inspired by concepts in classic 1980s distributed OSes. Translucent abstractions free users from having to understand implementation details, but enable introspection for performance optimisation. Fine-grained access control is supported by combining storable, communicable identifier capabilities, and context-dependent, ephemeral handle capabilities. Finally, multi-phase I/O requests implement optimistically concurrent access to objects while supporting diverse application-level consistency policies. Second, I present the DIOS operating system, an implementation of my model as an extension to Linux. The DIOS system call API is centred around distributed objects, globally resolvable names, and translucent references that carry context-sensitive object meta-data. I illustrate how these concepts support distributed applications, and evaluate the performance of DIOS in microbenchmarks and a data-intensive MapReduce application. I find that it offers improved, finegrained isolation of resources, while permitting flexible sharing. Third, I present the Firmament cluster scheduler, which generalises prior work on scheduling via minimum-cost flow optimisation. Firmament can flexibly express many scheduling policies using pluggable cost models; it makes high-quality placement decisions based on fine-grained information about tasks and resources; and it scales the flow-based scheduling approach to very large clusters. In two case studies, I show that Firmament supports policies that reduce colocation interference between tasks and that it successfully exploits flexibility in the workload to improve the energy efficiency of a heterogeneous cluster. Moreover, my evaluation shows that Firmament scales the minimum-cost flow optimisation to clusters of tens of thousands of machines while still making sub-second placement decisions.St John's College Supplementary Emolument Fund DARP

Long View (41RB112): Data Recovery of Two Plains Village Period Components in Roberts County, Texas, Volume 2

This archeological data recovery investigation in Roberts County in the northeastern panhandle of Texas was necessitated by the proposed widening of State Highway 70 (CSJ: 0490-04-037) by the Texas Department of Transportation (TxDOT), Amarillo District. This proposed highway rehabilitation program will directly impact a roughly 10 meter (m, 30 ft.) wide north-south section of prehistoric site 41RB112, the Long View site. This site consists of two horizontally distinct Plains Village period occupations shallowly buried along a linear interfluvial ridge between two small tributary creeks to the Canadian River in the midslope of this broad, dissected valley. This site was initially discovered by TxDOT archeologist, Dennis Price in June 2004 during an archeological inventory of the proposed 9.7 kilometer (6 mile) section north of the Canadian River in response to the planned highway rehabilitation program. Based on Mr. Price’s discovery of multiple artifact classes in buried context he recommended this site be assessed for its eligibility for listing on the National Register of Historic Places under criterion d and possible designation as a State Archeological Landmark (SAL) per the requirements of Section 106 of the National Historic Preservation Act (NHPA) and other related legislation. Following the Texas Historical Commissions concurrence with that recommendation, TxDOT through the Environmental (ENV) Affairs Division, contracted to TRC Environmental Corporation (TRC) under an existing Scientific Services Contract No. 57XXSA006 and issued a Work Authorization to TRC of Austin to conduct the site eligibility assessment. During a site visit by TxDOT geoarcheologist James Abbott and TRC archeologist Mike Quigg in February 2005, the site boundaries were expanded to nearly 300 meters (m) along the proposed area of potential effect (APE). Investigative strategies were devised to assess the Long View site. In May 2005, TRC’s archeologists from Austin conducted archeological testing for a NRHP and SAL eligibility assessment investigation at 41RB112. The assessment along the 10-m-wide by 300-m-long APE was accomplished by hand-excavating 28 1-by-1 m units (totaling 16.8 m3), hand-excavating four narrow ca. 30 centimeter (cm) wide trenches (two in each area totaling nearly 32 linear meters), as well as cleaning and inspecting 28 m of existing road cut exposures. These investigations determined that cultural materials clustered at the northern and southern ends (Areas A and C respectively) of the site with nearly 120 m of noncultural bearing deposits (Area B) between the two concentrations. A 4-m-wide mechanically bladed fireguard paralleled the existing fenceline throughout the length of the APE and disturbed much of the near surface materials in that zone. The opposite, eastern side of the highway was investigated through the excavation of six 50-by-50 cm shovel tests, surface, and road cut inspection. Based on the results from the hand-excavations and various collections conducted during the site assessment, it became apparent that the two ends (Areas A and C) of the Long View site in TxDOT’s proposed APE contained well-defined cultural components in the top 50 cmbs. Each end appeared to represent habitation remains from single occupation episodes with potential structures, restricted to a narrow time period of less than 100 years between uncalibrated 630 and 710 B.P. of the Plains Village period. Rodent and natural disturbances had vertically displaced some small cultural objects within the sandy deposits, but the restricted period of occupation to roughly a 100 year period reduces this impact. TRC recommended the site was eligible for listing on the National Register and as a State Landmark. The Texas Historical Commissions concurred with that recommendation, and subsequently the ENV Affairs Division of TxDOT, again contracted to TRC under an existing Scientific Services Contract No. 575XXSA008 and issued a Work Authorization to TRC Austin to perform the mitigation of the proposed impacts. Data recovery investigations were conducted during August through November 2006 along the western side of the existing highway. The previously identified northern-Area A and southern–Area C areas with high concentrations of cultural materials were targeted. These investigations began with a thorough geophysical survey that employed three noninvasive electrical detective instruments across Areas A and C anticipating to detect the locations of subsurface cultural features to target by hand-excavations. Some excavations targeted the detected anomalies, whereas others targeted previously identified features. In the end, hand-excavated blocks were completed in Areas A and C. The excavations totaled 128 m2 in Area A and 93 m2 in Area C for a grand total of 221 m2 or 103.4 m3. In conjunction with the archeological excavations, geoarcheological investigations focused on defining the age and development of the natural Holocene sediments that contained the cultural materials. The geoarcheological assessment included detailed stratigraphic documentation of site and near site deposits, sediment texture characterization, soil thin sections, magnetic susceptibility, multiple chemical analyses (organic, calcium, and phosphorus). Detailed stratigraphic data was also collected at two rare pithouse structures to pursue construction and filling episodes. The excavations yielded significant and diverse cultural assemblages from the two occupations assigned Component A and C. Both components are attributed to the Plains Village period with two discrete occupations dating to uncalibrated 460 to 535 B.P. (cal A.D. 1398 to 1447) in Component A and 530 to 700 B.P. (cal A.D. 1280 to 1437) in Component C. The two assemblages are significant not only in their diversity and quality of materials but also in the information they yielded. This report represents one of the first complete documents to present the entire cultural assemblage from a single site for this time period and region. The total recovered assemblage includes 157 formal chipped and ground stone tools, 226 informal tools, 3,414 pieces of lithic debitage, over 6,400 faunal fragments (1.4 kg), some 1,541 ceramic sherds, 1,790 burned rocks, at least 116 macrobotanical samples that includes 16 maize cobs, two human burials, and remains of a third, juvenile scattered along a previously bladed fireguard, 32 intact cultural features that include two rare pithouses, and other cultural debris related to these two campsites. The human remains and associated artifacts will be repatriated in accord with the requirements of the Native American Graves Protection and Repatriation Act (NAGPRA). A suite of 10 technical analyses directed at mostly the cultural assemblages included; use-wear, phytolith, diatom, petrography, macrobotanical, starch grain, instrumental neutron activation, bison bone isotopes, obsidian sourcing, radiocarbon and optical stimulated dating. This data was used to address 11 specific research questions concerning these Plains Village period occupations. Not only does the cultural debris contribute to our understanding of the time period but the geoarcheological information obtained explains the conditions and how the materials were preserved, and inform us concerning the past depositional environment in this immediate area. The combined information contributes to a significant understanding to a specific part of the Plains Village cultures in the Texas panhandle. Following the acceptance of the final report by the TxDOT and the Texas Historical Commission these cultural materials and all the documentation from the combined investigations will be permanently curated at Texas State University in San Marcos, Texas. The curated materials will provide important data that can be researched by interested parties in the future