1,012 research outputs found

    Applying geomorphological principles and engineering science to develop a phased sediment management plan for Mount St Helens, Washington

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    Thirty-seven years post-eruption, erosion of the debris avalanche at Mount St. Helens continues to supply sediment to the Toutle-Cowlitz River system in quantities that have the potential to lower the Level of Protection (LoP) against flooding unacceptably, making this one of the most protracted gravel-bed river disasters to date. The Portland District, US Army Corps of Engineers (USACE) recently revised its long-term plan for sediment management (originally published in 1985), in order to maintain the LoP above the Congressionally-authorised level, while reducing impacts on fish currently listed under the Endangered Species Act, and minimising the overall cost of managing sediment derived from erosion at Mount St Helens. In revising the plan, the USACE drew on evidence gained from sediment monitoring, modelling and uncertainty analysis, coupled with assessment of future LoP trends under a baseline scenario (continuation of the 1985 sediment management strategy) and feasible alternatives. They applied geomorphological principles and used engineering science to develop a Phased Sediment Management Plan that allows for uncertainty concerning future sediment yields by implementing sediment management actions only as, and when, necessary. The phased plan makes best use of the potential to enhance the sediment trap efficiency and storage capacity of the existing Sediment Retention Structure (SRS) by incrementally raising its spillway and using novel hydraulic structures to build islands in the NFTR and steepen the gradient of the sediment plain upstream of the structure. Dredging is held in reserve, to be performed only when necessary to react to unexpectedly high sedimentation events or when the utility of other measures has been expended. The engineering-geomorphic principles and many of the measures in the Phased Sediment Management Plan are transferrable to other gravel-bed river disasters. The overriding message is that monitoring and adaptive management are crucial components of long-term sediment-disaster management, especially in volcanic landscapes where future sediment yields are characterised by uncertainty and natural variability

    An availability study for a SME

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    A case study of an availability analysis for a small commercial company is presented. The analysis was carried out to meet a customer requirement for the availability of an electronic ground-based system in a benign environment. Availability calculations were based on failure data provided and an explanation of the methodology and problems encountered and dealt with are discussed. The methodology includes failure classification according to MIL-HDBK-781A and how it may be used to promote and develop internal processes. A commentary on the background to reliability/availability specification is provided and a number of recommendations for monitoring reliability and availability are given

    Flood realities, perceptions, and the depth of divisions on climate

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    Research has led to broad agreement among scientists that anthropogenic climate change is happening now and likely to worsen. In contrast to scientific agreement, US public views remain deeply divided, largely along ideological lines. Science communication has been neutralised in some arenas by intense counter-messaging, but as adverse climate impacts become manifest they might intervene more persuasively in local perceptions. We look for evidence of this occurring with regard to realities and perceptions of flooding in the northeastern US state of New Hampshire. Although precipitation and flood damage have increased, with ample news coverage, most residents do not see a trend. Nor do perceptions about past and future local flooding correlate with regional impacts or vulnerability. Instead, such perceptions follow ideological patterns resembling those of global climate change. That information about the physical world can be substantially filtered by ideology is a common finding from sociological environment/society research

    Academic Year 2025–26 Annual Estimate of the Strategic Security Environment

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    Maintaining strategic advantage demands professional discourse from across the force. The Academic Year 2025–26 Annual Estimate of the Strategic Security Environment provides a framework for those aspiring to tackle the Department of Defense’s most pressing challenges. This year’s authors highlight trending challenges and identify potential tension points across 15 sections organized into four enduring themes. This survey of regional, domestic, and institutional challenges represents the collective expertise of the US Army War College. The narrative is supplemented by a tailored list of 100 command-sponsored questions from 43 different Army and Joint organizations from across the Department of Defense. Combined, the distinct yet complementary narrative and question list offer unique insights into the vital matters impacting defense organizations and provide aspiring researchers with a necessary starting point.https://press.armywarcollege.edu/monographs/1975/thumbnail.jp

    Angle of Incidence Effects on Far-Field Positive and Negative Phase Blast Parameters

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    The blast overpressure acting on a rigid target is known to vary between the normally reflected overpressure and the incident overpressure as a function of the angle between the target and the direction of travel of the blast wave. Literature guidance for determining the exact effects of angle of incidence are unclear, particularly when considering the negative phase. This paper presents the results from a series of well controlled experiments where pressure transducers are used to record the pressure-time history acting on the face of a large, rigid target at various angles of incidence for varying sizes of hemispherical PE4 charge and stand-off distances. The test data demonstrated remarkable repeatability, and excellent agreement with semi-empirical predictions for normally reflected overpressures. The oblique results show that peak overpressure, impulse and duration are highly dependent on angle of incidence for the positive phase, and are invariant of angle of incidence for the negative phase

    AR 10-50, Organization and Functions, United States Army Medical Intelligence and Information Agency, 15 December 1980.

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    The purpose of the regulation is described as setting “… forth the mission and functions of the Director, US Army Medical Intelligence and Information Agency (USMIIA)…” The mission of the USMIIA…”is to produce timely medical intelligence support to the following: Offices of The Surgeons General, major commands, and staffs of the Army, Navy, and Air Force. DOD [Department of Defense] and national level intelligence production agencies. Other Government agencies as required. [and] Administer and coordinate the medical aspects of the Army Foreign Materiel Exploitation Program. “ This regulation states more clearly than the 1975 edition, that the USMIIA provided medical intelligence support for the entire US armed forces. Under the section on Command and Staff relationships, USMIIA was described as a field operating agency of The Surgeon General, US Army. In other words, the USMIIA was a special purpose organization reporting to The Surgeon General, chief of the Army Medical Department and senior medical staff officer in the US Department of the Army

    EIG 21, Collection of Information on Highways, May 1959.

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    This Engineer Intelligence Guide was prepared to provide intelligence collection, processing, production, and dissemination guidance by the Chief of Engineers to elements of the Corps of Engineers. The Introduction contains a list of five key army manuals and documents related to transportation intelligence. This guide contains detailed instructions for gathering information about highways and bridges. It also contains extensive illustrations and a glossary of highway terms. The distribution list shows engineer-related organizations interested in engineer intelligence

    Relinquishing and Governing the Volatile: The Many Afghanistans and Critical Research Agendas of NATO's Governance

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    This article invites academics and policy analysts to examine the mechanisms and legacy of NATO's security and development governance of Afghan social spaces by using critical theory concepts. It argues that such scholarly endeavors are growing in importance as the United States and NATO gradually pull their troops out of Afghanistan. Thus, the article suggests a broad twofold research agenda. First, it points out that researching social spaces such as towns, villages, marketplaces, and neighborhoods beyond the realm of intergovernmental politics can lead to thick descriptions of how such places have been governed from within by agents external to them. Second, the study argues for a multifaceted examination of instruments, strategies, and institutions of security governance, its conduct and social effects by deploying critical and Foucauldian concepts such as the rationality and apparatuses of power relations. Thereby, it proposes an inquiry into Provincial Reconstruction Teams and Afghan National Security Forces as spatially and temporally specific apparatuses of surveillance and security

    EIG 21, Collection of Information on Highways, May 1959.

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    This Engineer Intelligence Guide was prepared to provide intelligence collection, processing, production, and dissemination guidance by the Chief of Engineers to elements of the Corps of Engineers. The Introduction contains a list of five key army manuals and documents related to transportation intelligence. This guide contains detailed instructions for gathering information about highways and bridges. It also contains extensive illustrations and a glossary of highway terms. The distribution list shows engineer-related organizations interested in engineer intelligence

    W431-001 - US Army Air Corp Cadet Training Program: Administrative Records

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