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In many legal proceedings, fact finders scrutinize the demeanor of a defendant or witness, particularly his or her nonverbal behavior, for indicators of deception. This meta-analysis investigated directly observable nonverbal correlates of deception as a function of different moderator variables. Although lay people and professionals alike assume that many nonverbal behaviors are displayed more frequently while lying, of 11 different behaviors observable in the head and body area, only 3 were reliably associated with deception. Nodding, foot and leg movements, and hand movements were negatively related to deception in the overall analyses weighted by sample size. Most people assume that nonverbal behaviors increase while lying; however, these behaviors decreased, whereas others showed no change. There was no evidence that people avoid eye contact while lying, although around the world, gaze aversion is deemed the most important signal of deception. Most effect sizes were found to be heterogeneous. Analyses of moderator variables revealed that many of the observed relationships varied as a function of content, motivation, preparation, sanctioning of the lie, experimental design, and operationalization. Existing theories cannot readily account for the heterogeneity in findings. Thus, practitioners are cautioned against using these indicators in assessing the truthfulness of oral reports. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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All boiling water reactor (BWR) degraded core experiments performed prior to CORA-33 were conducted under ‘wet’ core degradation conditions, in which water remains within the core and continuous steaming feeds metal-steam oxidation reactions on the in-core metallic surfaces. However, one dominant set of accident scenarios would occur with reduced metal oxidation under ‘dry’ core degradation conditions and, prior to CORA-33, this set had been neglected experimentally. The CORA-33 experiment was designed specifically to address this dominant set of BWR ‘dry’ core severe accident scenarios and to resolve partially phenomenological uncertainties concerning the behavior of relocating metallic melts that drain into the lower regions of a ‘dry’ BWR core (the ex-reactor experiments at Sandia National Laboratories will further address these uncertainties). CORA-33 was conducted on 1 October 1992, in the CORA test facility at Karlsruhe. A review of the CORA-33 data indicates that the objectives were achieved; i.e. core degradation occurred at a core heat-up rate (characterized by the absence of any temperature escalation caused by oxidation) and a test section axial temperature profile (at incipient structural melting) that are prototypic of full-core nuclear power plant simulations under ‘dry’ core conditions. Simulations of the CORA-33 test at Oak Ridge National Laboratory (ORNL) have required the modification of existing control blade-canister materials interaction models to include the eutectic melting of the stainless steel-zircaloy interaction products and the heat of mixing of stainless steel and zircaloy. The timing and location of canister failure and melt intrusion into the fuel assembly appear to be adequately simulated by the ORNL models. This paper will present the results of the post-test analyses carried out at ORNL based on the experimental data and the post-test examination of the test bundle at Karlsruhe. The implications of these results with respect to degraded core modelling and the associated safety issues are also discussed.  相似文献   
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Crease surfaces describe extremal structures of 3D scalar fields. We present a new region-growing-based approach to the meshless extraction of adaptive nonmanifold valley and ridge surfaces that overcomes limitations of previous approaches by decoupling point seeding and triangulation of the surface. Our method is capable of extracting valley surface skeletons as connected minimum structures. As our algorithm is inherently mesh-free and curvature adaptive, it is suitable for surface construction in fields with an arbitrary neighborhood structure. As an application for insightful visualization with valley surfaces, we choose a low frequency acoustics simulation. We use our valley surface construction approach to visualize the resulting complex-valued scalar pressure field for arbitrary frequencies to identify regions of sound cancellation. This provides an expressive visualization of the topology of wave node and antinode structures in simulated acoustics.  相似文献   
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Zusammenfassung In Modellversuchen wurden Haselnüsse, Sojabohnen und Weizen bei zeitlich nicht konstanter Konzentration mit Phosphin begast. Dabei wurden — in Anlehnung an die Begasungspraxis —verschiedene Konzentrationsverläufe mit zunächst ansteigender und nach Überschreiten eines Maximums wieder abfallender PH3-Konzentration hinsichtlich des Einflusses auf die Rückstandsbildung bzw. den Rückstandsabbau untersucht. Die Rückstandshöhe während der Begasung als auch das Rückstandsverhalten bei der anschließenden Lagerung der behandelten Produkte wurde mit einem gaschromatographischen Verfahren überwacht. Die sich bildenden Phosphin-Rückstände folgen dabei der Tendenz nach dem Konzentrationsprofil, sie durchlaufen ebenfalls ein Maximalwert. Rückstände, die in der Phase der ansteigenden Konzentration entstehen, bauen jedoch bei der Lagerung schneller ab als gleich hohe Rückstände, die sich in der Zeit der absinkenden Konzentration bilden. Bei sehr flach verlaufender Konzentration tritt der Maximal-Rückstand gegenüber dem Konzentrationsmaximum zeitlich verzögert auf, bei sehr steilem Konzentrationsverlauf fallen beide Maxima zusammen. Die Vorgänge lassen sich durch das Diffusions- und Sorptionsverhalten des Phosphins begründen. Es wird ein Vergleich mit dem Konzentrationsverlauf bei Praxisbegasungen geführt. Die Einflüsse, die ein stetiges Konzentrationsprofil mit nur einem Maximum bzw. einen Verlauf mit häufig steigender und fallender Konzentration bedingen, werden erläutert und das in beiden Fällen unterschiedliche Rückstandsverhalten untersucht und diskutiert. Schlußfolgerungen für die Begasungspraxis werden gezogen.
Phosphine residues in hazelnuts, soybeans, and wheat after fumigation with non constant cocentrations
Summary In model tests hazelnuts, soy beans and wheat were fumigated with phosphine (PH3) at non constant concentrations. The influence of different concentration characteristics on the fumigation and the decomposition of phosphine residues was investigated in accordance with the fumigation technique. At the beginning the concentration increases, and after attaining the maximum gradually decreases to zero. The level of residues during the fumigation as well as the behaviour of residues during the storage of the fumigated products was monitored with a gaschromatographic method. The residues correlate with the concentration of phosphine, they also pass through a peak. The rate of decomposition of residues which had been formed in the phase of increasing concentration is greater than the rate of residues of equal magnitude which had been formed during the decreasing phase. When the concentration is even the maximum residue occurs later than the maximum concentration; when there is a steep trend both maximums coincide. This behaviour can be explained by the sorption and diffusion of phosphine. A comparison is made with the phosphine concentration which occurs during fumigation in practice. The parameters which produce a constant concentration trend with only one maximum and a non constant trend with an often increasing and decreasing concentration are discussed. The different behaviour of residues in these cases is described. Conclusions are drawn for the practice of fumigation.


Gefördert im Rahmen einer Sachbeihilfe der Deutschen Forschungsgemeinschaft an Dr. R. Wohlgemuth, Biologische Bundesanstalt für Land- und Forstwirtschaft, Institut für Vorratsschutz, Berlin-Dahlem, zum Thema: Untersuchungen zum Einfluß verschiedener Parameter auf die Rückstandsbildung bei der Begasung von Lebensmitteln gegen Schädlinge  相似文献   
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Metallurgical and Materials Transactions A - Co-based superalloys have been developed as candidate materials to replace Ni-based superalloys in hot sections of turbine engines, however, their...  相似文献   
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Abstract. Outliers in time series seriously affect conventional parameter estimates. In this paper a robust recursive estimation procedure for the parameters of auto-regressve moving-average models with additive outliers is proposed. Using 'cleaned' residuals from an initial robust fit of an autoregression of high order as input, bounded influence regression is applied recursively. The proposal follows certain ideas of Hannan and Rissanen, who suggested a three-stage procedure for order and parameter estimation in a conventional setting.
A Monte Carlo study is performed to investigate the robustness properties of the proposed class of estimates and to compare them with various other suggestions, including least squares, M estimates, residual autocovariance and truncated residual autocovariance estimates. The results show that the recursive generalized M estimates compare favourably with them. Finally, possible modifications to master even vigourous situations are suggested.  相似文献   
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