21 research outputs found

    Visualizing Social Networks to Inform Tactical Engagement Strategies that will Influence the Human Domain

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    The Special Operations Command, Marine Corps, and Army recently formed the Strategic Landpower Task Force to study the confluence of the land, cyber, and human domains. To support the Task Force’s research, this paper demonstrates the utility of visualizing social networks in order to inform a unit’s population tactical engagement strategy. We illustrate how collecting, structuring and visualizing socio-cultural data can assist units to rapidly communicate human dynamics, visualize community and group affiliations, prepare for key leader engagements, highlight potential powerbrokers, and identify information gaps about the human terrain. We provide real world examples from a recent deployment to Kandahar, Afghanistan. These examples reveal how social network and link analysis can assist units to understand and influence the human domain at the tactical level

    Development of Fluid-Curtain Sealing Technology to Improve the Efficiency and Operational Flexibility of Large Power Generation Turbines

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    Fluidic curtain sealing has recently been shown to offer significantly reduced leakage in rotating turbomachinery seals. The seal type uses an additional flow injected into the leakage path to reduce some existing leakage flow. Shrouded steam turbine tip seals were the focus of research in this thesis, but the seal has potential applications in blade tip seals, stator root seals, shaft seals, and end gland seals in steam turbines as well as in gas turbines. The implementation of such a seal may be simplified in the case of gas turbines since secondary flows of air are already built into the machine to provide cooling flows to high temperature components. The fluidic curtain seal is especially effective when a combination of fluidic curtain and a conventional labyrinth seal is used, and the research presented will generally feature a fluidic curtain placed upstream of a labyrinth fin type restriction. The new addition to knowledge on fluidic curtain sealing described in this work is in characterising seal performance in terms of its design parameters. Better characterisation of the seal allows the development of a set of realistic design rules to specify how fluidic curtains may be applied to the design of new, high performance turbomachinery seals. Two main advances in characterising fluidic curtain seals resulted from the research. The first advance was to numerically and experimentally test basic geometric parameters and their influence on performance to identify design rules which maximize the performance gain of incorporating a fluidic curtain. A series of fundamental dimensionless geometric ratios were proposed and the design space created by these parameters was explored and validated experimentally using a simple annular test rig. CFD was then used to demonstrate that it is possible to incorporate a high performance design into a labyrinth seal independent of the existing labyrinth seal geometry. The second advance is to explore the effect of swirl velocity at the leakage channel inlet on overall seal performance. This was first achieved using CFD to model the selected realistic tip seal design with different levels of inlet swirl. This CFD study was then validated by building the design in a rotating annular test rig where the inlet swirl velocity was controlled. The research findings resulted in a proposed design process for new fluidic curtain seals (Section 8.2) which considers; the geometry of an existing seal, fluid conditions in the leakage path and elsewhere in the turbine stage, rotational speed, and minimum allowable physical clearances

    Urinary biomarker concentrations of captan, chlormequat, chlorpyrifos and cypermethrin in UK adults and children living near agricultural land

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    There is limited information on the exposure to pesticides experienced by UK residents living near agricultural land. This study aimed to investigate their pesticide exposure in relation to spray events. Farmers treating crops with captan, chlormequat, chlorpyrifos or cypermethrin provided spray event information. Adults and children residing ≤100 m from sprayed fields provided first-morning void urine samples during and outwith the spray season. Selected samples (1–2 days after a spray event and at other times (background samples)) were analysed and creatinine adjusted. Generalised Linear Mixed Models were used to investigate if urinary biomarkers of these pesticides were elevated after spray events. The final data set for statistical analysis contained 1518 urine samples from 140 participants, consisting of 523 spray event and 995 background samples which were analysed for pesticide urinary biomarkers. For captan and cypermethrin, the proportion of values below the limit of detection was greater than 80%, with no difference between spray event and background samples. For chlormequat and chlorpyrifos, the geometric mean urinary biomarker concentrations following spray events were 15.4 μg/g creatinine and 2.5 μg/g creatinine, respectively, compared with 16.5 μg/g creatinine and 3.0 μg/g creatinine for background samples within the spraying season. Outwith the spraying season, concentrations for chlorpyrifos were the same as those within spraying season backgrounds, but for chlormequat, lower concentrations were observed outwith the spraying season (12.3 μg/g creatinine). Overall, we observed no evidence indicative of additional urinary pesticide biomarker excretion as a result of spray events, suggesting that sources other than local spraying are responsible for the relatively low urinary pesticide biomarkers detected in the study population

    Regulated Expression of ADAMTS-12 in Human Trophoblastic Cells: A Role for ADAMTS-12 in Epithelial Cell Invasion?

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    Metastatic carcinoma cells exploit the same molecular machinery that allows human placental cytotrophoblasts to develop an invasive phenotype. As altered expression levels of ADAMTS (A Disintegrin And Metalloproteinase with ThromboSpondin repeats) subtypes have been associated with cancer progression, we have examined the function and regulation of members of this gene family in epithelial cell invasion using cultures of highly invasive extravillous cytotrophoblasts and the poorly invasive JEG-3 cytotrophoblast cell line as model systems. Of the multiple ADAMTS subtypes identified in first trimester human placenta and these two trophoblastic cell types, only ADAMTS-12 was preferentially expressed by extravillous cytotrophoblasts. Transforming growth factor-β1 and interleukin-1β, two cytokines that promote and restrain cytotrophoblast invasion in vitro, were also found to differentially regulate trophoblastic ADAMTS-12 mRNA levels. Loss- or gain-of-function studies confirmed that ADAMTS-12, independent of its proteolytic activity, plays a specific, non-redundant role in trophoblast invasion. Furthermore, we demonstrated that ADAMTS-12 regulated cell-extracellular matrix adhesion and invasion through a mechanism involving the αvβ3 integrin heterodimer. This study identifies a novel biological role for ADAMTS-12, and highlights the importance and complexity of its non-proteolytic domain(s) pertaining to its function

    Влияние фосфатных связующих на физико-механические свойства периклазохромитовых огнеупоров

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    У данній статті наведено та порівняно фізико-механічні властивості периклазо-хромітових матеріалів в залежності від різних типів фосфатних зв’язуючих та введення різних домішок. Визначено, що найбільш раціональним є введення триполіфосфату натрію.In given clause are resulted and the physycal-mechanical properties periclase-cgromite of materials are compared depending on different of types phosphate binding and introduction of the various additives. Is determined, that most rational is the introduction treepolyphosphate sodume

    Flexible space-filling designs for complex system simulations

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    In order to better understand the complex nature of a system, analysts need efficient experimental designs that can explore high-dimensional simulation models with multiple outputs. These simulation models are critical to the early phases of system design and involve complicated outputs with a wide variety of linear and nonlinear response surface forms. The most common response surface form for analyzing complex systems is the second-order model. Traditional designs that fit second-order response surface models do not effectively explore the interior of the experimental region and cannot fit higher-order models. We present a genetic algorithm that constructs space-filling designs with minimal correlations between all second-order terms for a mix of continuous and discrete factor types. These designs are specifically suited to fit the second-order model with excellent space-filling properties and are flexible enough to fit higher-order models for a modest number of factors; these high-order terms are what characterize the system complexities. We demonstrate the utility of these designs with a Model-Based Systems Engineering application that integrates multiple simulation outputs to form a trade-off environment for a system design. This research enables the simulation analysis and system design community to better understand the complex nature of multiple simulation outputs.http://archive.org/details/flexiblespacefil1094534701Lieutenant Colonel, United States ArmyApproved for public release; distribution is unlimited

    Collaborative efforts in advancing the state-of-the-art of early stage ship design

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    Version lists all four author names.The design process for a new warship requires the selection of the configuration and specific characteristics that will result in satisfying requirements in a operationally effective manner. Traditionally, the initial phase of Concept Definition was based on experience, on the balanced application of project constraints, on empirical rules and experimental information, and on analytical insights into the technologies that are being considered for the new warship. This knowledge was employed within a consolidated team of experts who balance requirements, constraints and resources. However, a key aspect of successful ship design is the need to begin the process with an understanding of the missions that this ship will undergo, as well as a clear definition of mission success. A collaborative team of researchers from academia and industry, led by Orizzonte Sistemi Navali (OSN), is applying this "mission-focus" to Early Stage Ship Design (ESSD). This multi-year effort has the primary goal of linking operational effectiveness and design characteristic information that support a deeper understanding of their relationships within the ship concept design process. This paper provides a thorough vision of the efforts developed and implemented by OSN and their research partners, to include a summary of national and international research projects, describing the final objective of producing and delivering a warship where the effectiveness of the entire warship is addressed during the earliest stages of design. OSN instantiated this effort by establishing a collaborative, real-time environment in which operational needs and engineering design considerations are both represented within a coherent and integrated ship development process.Office of Naval Research and Orizzonte Sistemi NavaliApproved for public release; distribution is unlimited

    On the effect of wearing personal nanoparticle monitors on the comparability of personal exposure measurements

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    Wearing of personal monitors for nanoparticle exposure studies does not affect the measurement performance compared to laboratory studies.</p
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