3,076 research outputs found

    JT8D-15/17 High Pressure Turbine Root Discharged Blade Performance Improvement

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    The JT8D high pressure turbine blade and seal were modified, using a more efficient blade cooling system, improved airfoil aerodynamics, more effective control of secondary flows, and improved blade tip sealing. Engine testing was conducted to determine the effect of these improvements on performance. The modified turbine package demonstrated significant thrust specific fuel consumption and exhaust gas temperature improvements in sea level and altitude engine tests. Inspection of the improved blade and seal hardware after testing revealed no unusual wear or degradation

    Substantive Due Process and the Involuntary Confinement of Sexually Violent Predators

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    Over the past fifty years the Supreme Court has been repeatedly asked to address the constitutionality of civil commitment laws, including laws specifically targeting sexually violent predators (SVPs). The SVP laws have withstood challenge, in each instance redeemed by their putative civil purpose. Today, however, roughly 13 years after the first modern SVP law was enacted by the State of Washington, serious concern exists over whether the laws are fulfilling their civil purpose, or are merely serving as vehicles for impermissible preventive detention. This Article addresses this question, in the process exploring the viability of the major remaining constitutional basis to challenge the laws: that police power commitment authority entails a strong, enforceable right to treatment, indeed, effective treatment, designed to achieve material progress toward community re-entry. Our argument takes on the conventional judicial wisdom that discounts the right to treatment for the dangerous mentally disordered. Tying together thirty years of the Court\u27s cases, we establish that without treatment progress, involuntary civil commitment, although perhaps legitimate ab initio, can over time become unconstitutional punishment. To ensure that this principle is honored, we devise an analytic framework that is sensitive to the deference properly owed states in the operation of their SVP regimes, yet fulfills the imperative that courts carefully scrutinize state deprivations of liberty on the cusp of the shadowy civil-criminal divide. The Article begins by discussing Seling v. Young, in which the Supreme Court turned back a right-to-treatment claim for habeas relief. Noting that Young was an ex post facto/double jeopardy case, the Article turns to the Court\u27s substantive due process jurisprudence. We argue that there are limits to the hands-off deference that courts often express regarding treatment claims. The right to treatment is often thought of in monolithic terms. We argue that the constitutional right to treatment has several distinct analytic branches. Treatment must be a purpose of commitment if it is to retain its civil cast. However, for a variety of reasons, the Constitution does not impose a treatment-amenability standard as a pre-condition for police power commitment. Further, the details of treatment are properly left to the discretion of state professionals. Nonetheless, the duration of confinement must be related to its treatment purpose. This principle suggests the invalidity of commitments whose duration is excessive in relation to a treatment purpose. In a series of cases, the Court has insisted that commitments, even those valid ab initio, must end when their constitutional underpinnings disappear. We argue that this principle requires release if effective treatment has not been provided within a reasonable period

    A Crooked Picture: Re-Framing the Problem of Child Sexual Abuse

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    Comparison of the USGS 2001 NLCD to the 2002 USDA Census of Agriculture for the Upper Midwest United States

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    The U.S. Geological Survey (USGS) 2001 National Land Cover Database (NLCD) was compared to the U.S. Department of Agriculture (USDA) 2002 Census of Agriculture. Wecompared areal estimates for cropland at the state and county level for 14 States in the Upper Midwest region of the United States. Absolute differences between the NLCD and Census cropland areal estimates at the state level ranged from 1.3% (Minnesota) to 37.0% (Wisconsin). The majority of counties (74.5%) had differences of less than 100 km2. 7.2% of the counties had differences of more than 200 km2. Regions where the largest areal differences occurred were in southern Illinois, North Dakota, South Dakota, and Wisconsin, and generally occurred in areas with the lowest proportions of cropland (i.e., dominated by forest or grassland). Before using the 2001 NLCD for agricultural applications, such as mapping of specific crop types, users should be aware of the potential for misclassification errors, especially where the proportion of cropland to other land cover types is fairly lo

    The potential for measuring ethnicity and health in a multicultural milieu - the case of type 2 diabetes in Australia

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    ObjectiveEthnicity influences health in many ways. For example, type 2&nbsp;diabetes (T2DM) is disproportionately prevalent among certain ethnic groups.&nbsp;Assessing ethnicity is difficult, and numerous proxy measures are used to&nbsp;capture its various components. Australian guidelines specify a set of&nbsp;variables for measuring ethnicity, and how such parameters should be&nbsp;categorised. Using T2DM data collections as an illustrative example, this&nbsp;study sought to examine how ethnicity is measured in Australian health&nbsp;databases and, by comparing current practice with Australia&rsquo;s existing&nbsp;benchmark recommendations, to identify potential areas for improvement of&nbsp;the health data landscape.DesignWe identified databases containing information from which ethnic&nbsp;group-specific estimates of T2DM burden may be gleaned. For each&nbsp;database, details regarding ethnicity variables were extracted, and compared&nbsp;with the Australian guidelines.&nbsp;ResultsData collection instruments for 32 relevant databases were reviewed.&nbsp;Birthplace was recorded in 27 databases (84%), but mode of birthplace&nbsp;assessment varied. Indigenous status was commonly recorded (78%, n=25), but&nbsp;only nine databases recorded other aspects of self-perceived race/ethnicity. Of&nbsp;28 survey/audit databases, 14 accommodated linguistic preferences other than&nbsp;English, and 11 either excluded non-English speakers or those for whom a&nbsp;translator was not available, or only offered questionnaires in English.ConclusionsConsiderable variation exists in the measurement of ethnicity in&nbsp;Australian health data- sets. While various markers of ethnicity provide&nbsp;complementary information about the ethnic profile within a data-set, nonuniform&nbsp;measurement renders comparison between data-sets difficult. A&nbsp;standardised approach is necessary, and identifying the ethnicity variables&nbsp;that are particularly relevant to the health sector is warranted. Including self identified&nbsp;ethnicity in Australia&rsquo;s set of recommended indicators and as a core&nbsp;component of the national census should be considered. Globalisation and&nbsp;increasing migration mean that these findings have implications internationally,&nbsp;including for multi-ethnic countries throughout North America and&nbsp;Europe.</div

    An in-depth view of the microscopic dynamics of Ising spin glasses at fixed temperature

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    Using the dedicated computer Janus, we follow the nonequilibrium dynamics of the Ising spin glass in three dimensions for eleven orders of magnitude. The use of integral estimators for the coherence and correlation lengths allows us to study dynamic heterogeneities and the presence of a replicon mode and to obtain safe bounds on the Edwards-Anderson order parameter below the critical temperature. We obtain good agreement with experimental determinations of the temperature-dependent decay exponents for the thermoremanent magnetization. This magnitude is observed to scale with the much harder to measure coherence length, a potentially useful result for experimentalists. The exponents for energy relaxation display a linear dependence on temperature and reasonable extrapolations to the critical point. We conclude examining the time growth of the coherence length, with a comparison of critical and activated dynamics.Comment: 38 pages, 26 figure

    Matching microscopic and macroscopic responses in glasses

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    We first reproduce on the Janus and Janus II computers a milestone experiment that measures the spin-glass coherence length through the lowering of free-energy barriers induced by the Zeeman effect. Secondly we determine the scaling behavior that allows a quantitative analysis of a new experiment reported in the companion Letter [S. Guchhait and R. Orbach, Phys. Rev. Lett. 118, 157203 (2017)]. The value of the coherence length estimated through the analysis of microscopic correlation functions turns out to be quantitatively consistent with its measurement through macroscopic response functions. Further, non-linear susceptibilities, recently measured in glass-forming liquids, scale as powers of the same microscopic length.Comment: 6 pages, 4 figure

    The Mpemba effect in spin glasses is a persistent memory effect

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    The Mpemba effect occurs when a hot system cools faster than an initially colder one, when both are refrigerated in the same thermal reservoir. Using the custom built supercomputer Janus II, we study the Mpemba effect in spin glasses and show that it is a non-equilibrium process, governed by the coherence length \xi of the system. The effect occurs when the bath temperature lies in the glassy phase, but it is not necessary for the thermal protocol to cross the critical temperature. In fact, the Mpemba effect follows from a strong relationship between the internal energy and \xi that turns out to be a sure-tell sign of being in the glassy phase. Thus, the Mpemba effect presents itself as an intriguing new avenue for the experimental study of the coherence length in supercooled liquids and other glass formers.Comment: Version accepted for publication in PNAS. 6 pages, 7 figure

    The three dimensional Ising spin glass in an external magnetic field: the role of the silent majority

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    We perform equilibrium parallel-tempering simulations of the 3D Ising Edwards-Anderson spin glass in a field. A traditional analysis shows no signs of a phase transition. Yet, we encounter dramatic fluctuations in the behaviour of the model: Averages over all the data only describe the behaviour of a small fraction of it. Therefore we develop a new approach to study the equilibrium behaviour of the system, by classifying the measurements as a function of a conditioning variate. We propose a finite-size scaling analysis based on the probability distribution function of the conditioning variate, which may accelerate the convergence to the thermodynamic limit. In this way, we find a non-trivial spectrum of behaviours, where a part of the measurements behaves as the average, while the majority of them shows signs of scale invariance. As a result, we can estimate the temperature interval where the phase transition in a field ought to lie, if it exists. Although this would-be critical regime is unreachable with present resources, the numerical challenge is finally well posed.Comment: 42 pages, 19 figures. Minor changes and added figure (results unchanged

    Critical parameters of the three-dimensional Ising spin glass

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    We report a high-precision finite-size scaling study of the critical behavior of the three-dimensional Ising Edwards-Anderson model (the Ising spin glass). We have thermalized lattices up to L=40 using the Janus dedicated computer. Our analysis takes into account leading-order corrections to scaling. We obtain Tc = 1.1019(29) for the critical temperature, \nu = 2.562(42) for the thermal exponent, \eta = -0.3900(36) for the anomalous dimension and \omega = 1.12(10) for the exponent of the leading corrections to scaling. Standard (hyper)scaling relations yield \alpha = -5.69(13), \beta = 0.782(10) and \gamma = 6.13(11). We also compute several universal quantities at Tc.Comment: 9 pages, 5 figure
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