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In this paper, we present a tutorial overview of state-of-the-art radio frequency (RF) clutter modeling and simulation (M&S) techniques. Traditional statistical approximation based methods will be reviewed followed by more accurate physics-based stochastic transfer function clutter models that facilitate site-specific simulations anywhere on earth. The various factors that go into the computation of these transfer functions will be presented, followed by several examples across multiple RF applications. Finally, we introduce a radar challenge dataset generated using these tools that can enable testing and benchmarking of all cognitive radar algorithms and techniques., submitted to IEEE Aerospace and Electronic Systems Magazine

The Bishop Tuff (BT), erupted from the Long Valley caldera in California, displays two types of geochemical gradients with temperature: one is related to magma mixing, whereas the other is found in the high-SiO2 rhyolite portion of the Bishop Tuff and is characterized by twofold or lower concentration variations in minor and trace elements that are strongly correlated with temperature. It is proposed that the latter zonation, which preceded phenocryst growth, developed as a result of mineral–melt partitioning between interstitial melt and surrounding crystals in a parental mush, from which variable melt fractions were segregated. To test this hypothesis, trends of increasing vs decreasing element concentrations with temperature (as a proxy for melt fraction), obtained from published data on single-clast pumice samples from the high-SiO2 rhyolite portion of the Bishop Tuff, were used to infer their relative degrees of incompatibility vs compatibility between crystals and melt in the parental mush. Relative compatibility values (RCVi) for all elements i, defined as the concentration slope with temperature divided by average concentration, are shown to be linearly correlated with their respective bulk partition coefficients (bulk Di). Mineral–melt partition coefficients from the literature were used to constrain the average stoichiometry of the crystallization/melting reaction in the parental mush: 32 % quartz + 34 % plagioclase + 31 % K-feldspar + 1·60 % biotite + 0·42 % titanomagnetite + 0·34 % ilmenite + 0·093 % allanite + 0·024 % zircon + 0·025 % apatite = 100 % liquid. The proportions of tectosilicates in the reaction (i.e. location of eutectic) are consistent with depths of melt segregation of ~400–550 MPa and an activity of H2O of ~0·4–0·6. Temperatures of

Chennai (Tamil Nadu, India) and Durban (Kwazulu-Natal, South Africa) have both used growth corridors to support their dominant political and economic roles within their state or province and consolidate their position as regional hubs. These corridors are particular types of space that are ‘produced’ in order to drive economic growth and urban development. Giving expression to broader urban development strategies, they result from the coming together of actor networks, discourses, knowledge and materialities within a particular space. This chapter uses economic growth corridors as a lens to explore the coming together of interconnections that produce the city, which are interesting precisely because they are not representative of the entire city. More broadly, we focus on the urban governance configurations of growth corridors in both Chennai and Durban and compare the processes of megaproject development as a conceptual entrypoint to reflect on the ways in which fast growing, port-industrial cities are being (re-)invented. This chapter explores the very different configurations within the two cities that are nonetheless producing broadly similar outcomes with similar genealogies.

Combat actions are planned based on the best available information. In nearly all situations, significant uncertainty about the combat environment exists. This uncertainty contributes largely to friendly and non-combatant casualties. At the tactical level, operators are often required to enter hostile-occupied buildings without knowledge of the building layout. Military operators have begun to use robots to assist in missions of this type. In general, currently fielded robots lack autonomy and the ability to disseminate an accurate map, on-site, in real time. The purpose of this thesis is to examine the feasibility of an autonomous robot that can localize and build accurate 3D maps using only light detection and ranging (LIDAR). To accomplish this, a robot equipped with only LIDAR and a control algorithm for LIDAR localization and mapping (LLAM) were developed. Trials were then developed to determine if LLAM is a feasible model for interior 3D mapping. Navigation was accomplished using a potential field model adapted from previous work combined with the Hybrid A* search algorithm. Mapping and localization were conducted using the iterative closest point and normal distribution transform methods of point cloud registration. Experimentation revealed that LLAM is a feasible method for interior 3D mapping in real time. Further development of the algorithm may make fielding a LIDAR-equipped mapping robot possible with current mobile computing technology. Major, United States Marine Corps Approved for public release. distribution is unlimited

Numerous analyses of multiple ilmenite, titanomagnetite, sanidine, plagioclase, biotite, orthopyroxene, and clinopyroxene crystals (when present) in each of 24 single-clast pumices from the Bishop Tuff (BT), CA are presented, together with whole-rock compositions on the same single clasts. Data from multiple Fe–Ti oxide grains in each sample, coupled with an assessment of analytical uncertainty, show that there is a single population of ilmenite and titanomagnetite in each of 20 samples and no more than two populations of ilmenite and/or titanomagnetite in the remaining four. A statistical evaluation of microprobe uncertainty (for beam conditions of 15 kV and 10 nA) constrains the minimum number of ilmenite (≥ 21) and titanomagnetite (≥ 56) analyses required to obtain Fe–Ti two-oxide temperatures with propagated uncertainties ≤ ± 10 °C. Thermometry results confirm a continuous range (~ 700–800 °C) across the BT deposit. Plagioclase displays a bimodal compositional pattern, where a predominantly sodic (An14–15) vs. calcic (An22–23) population is found in single clasts where pyroxene is absent vs. present; the latter coincides with geochemical evidence for mixing between high-SiO2 rhyolite and less differentiated melts as previously documented in the literature. When sanidine rims are paired with plagioclase, calculated two-feldspar temperatures (~ 690–780 °C) are strongly correlated (R2 = 0.94) with Fe–Ti two-oxide temperatures. Application of plagioclase–liquid hygrometry reveals a systematic decrease in melt water content (~ 7.2–4.1 wt%) with increasing temperature across the BT deposit, consistent with experiments from the literature that show cotectic crystallization of quartz–sanidine–plagioclase in rhyolite melt requires a concomitant decrease of ~ 3 wt% H2O between 700 and 800 °C at 200 MPa. Single-clast, whole-rock concentrations of some elements (e.g., Rb) correlate strongly with Fe–Ti oxide temperature (R2 = 0.95). The Mg# in biotite also correlates strongly with temperature (R2 = 0.97), as do the Mg# values in orthopyroxene and clinopyroxene with whole-rock Mg# (R2 = 0.6 and 0.8, respectively) and melt water content (R2 = 0.7 for both). Evidence points to biotite crystallization in all BT samples from high-SiO2 rhyolite melt, which was already continuously zoned in composition and temperature prior to mixing with less differentiated melts, as previously noted in the literature. In contrast, several lines of evidence, including hydrous phase-equilibrium experiments on rhyolites from the literature, show that both pyroxenes in BT pumices co-crystallized with calcic plagioclase (~ An21–29), in equilibrium with both titanomagnetite and ilmenite, after mixing between less differentiated melt(s) and relatively hot (≥ 755 °C) high-SiO2 rhyolite.

Objectives To review the current best surgical practice and detail a multi-disciplinary approach that could further reduce joint replacement infection. Methods Review of relevant literature indexed in PubMed. Results Surgical site infection is a major complication following arthroplasty. Despite its rarity in contemporary orthopaedic practice, it remains difficult to treat and is costly in terms of both patient morbidity and long-term health care resources. Conclusions Emphasis on education of patients and all members of the health-care team and raising awareness in how to participate in preventative efforts is imperative.

This thesis places Chaucer within the tradition of philosophical poetry that begins in Plato and extends through classical and medieval Latin culture. In this Platonic tradition, poetry is a self-reflexive epistemological practice that interrogates the conditions of art in general. As such, poetry as metapoetics takes itself as its own object of inquiry in order to reinforce and generate its own definitions without regard to extrinsic considerations. It attempts to create a poetic-knowledge proper instead of one that is dependant on other modes for meaning. The particular manner in which this is expressed is according to the idea of the loss of the Golden Age. In the Augustinian context of Chaucer’s poetry, language, in its literal and historical signifying functions is an effect of the noetic fall and a deformation of an earlier symbolism. The Chaucerian poems this thesis considers concern themselves with the solution to a historical literary lament for language’s fall, a solution that suggests that the instability in language can be overcome with reference to what has been lost in language. The chapters are organized to reflect the medieval Neoplatonic ascensus. The first chapter concerns the Pardoner’s Old Man and his relationship to the literary history of Tithonus in which the renewing of youth is ironically promoted in order to perpetually delay eternity and make the current world co-eternal to the coming world. In the Miller’s Tale, more aggressive narrative strategies deploy the machinery of atheism in order to make a god-less universe the sufficient grounds for the transformation of a fallen and contingent world into the only world whatsoever. The Manciple’s Tale’s opposite strategy leaves the world intact in its current state and instead makes divine beings human. Phoebus expatriates to earth and attempts to co-mingle it with heaven in order to unify art and history into a single monistic experience. Finally, the Nun’s Priest’s Tale acts as ars poetica for the entire Chaucerian Performance and undercuts the naturalistic strategies of the first three poems by a long experiment in the philosophical conflict between art and history. By imagining art and history as epistemologically antagonistic it attempts to subdue in a definitive manner poetic strategies that would imagine human history as the necessary knowledge-condition for poetic language.

BackgroundAlthough malaria control programs have made rapid progress recently, they neglect important social and behavioral factors associated with the disease. Social, political, and cultural factors are involved in malaria control, and individuals in a community may be comfortable in behaving in ways that, to an outsider, may seem contrary to commonly held perceptions. Malaria control efforts can no longer afford to overlook the multidimensional human contexts that create and support varying notions of malaria and its prevention, treatment, and control. This study aimed to assess the knowledge and perceptions of malaria issues in the community, and to identify practices that support or hinder the progress of malaria control programs.MethodsA triangulation study involving individual interviews, focus group discussions, and observatory analysis between 2003 and 2010 at Lomahasha, a malarious community on the eastern border of Swaziland and Mozambique, was conducted.ResultsResults indicated that a high knowledge level and good perception of the disease were observed in the age group of < 40 years, contrary to those in higher age groups, among the Lomahasha community members. However, behavior of certain community groups includes practices that are not supportive of the national control program's aspirations, such as delay in seeking medical attention, staying outdoors until late, maintaining stagnant water in roadside excavations, and seeking medical assistance from wrong sources. Malpractices are more commonly observed among men, boys, and those who drink alcohol.ConclusionThis study suggests a thorough community diagnosis before all intervention programs for malaria control are instituted.

This retrospective cohort study of a National Joint Registry data examines survival time to revision following the commonest brand of primary hybrid THA, exploring risk factors independently associated with failure. Overall 5-year revision was 1.56%. In the final adjusted model, revision risk was significantly higher with standard polyethylene (PE) liners (metal-on-PE: hazard ratio [HR] = 2.52, P = 0.005, ceramic-on-PE: HR = 2.99, P = 0.025) when compared to metal-on-highly-cross-linked (XL) PE. Risk of revision with ceramic-on-ceramic bearings was borderline significant (HR = 1.86, P = 0.061). A significant interaction between age and acetabular shell type (solid or multi-hole) was found (P = 0.022), suggesting that solid shells performed significantly better in younger patients. In summary, we found that there were significant differences in implant failure between different bearing surfaces and shell types after adjusting for a range of covariates.

Objective: Medical complications and death are rare events following elective orthopaedic surgery. Diagnostic and operative codes are routinely collected on every patient admitted to hospital in the English NHS (hospital episode statistics, HES). This is the first study investigating morbidity and[for full text, please go to the a.m. URL], Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2013)