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1.
Melt-textured YBa2Cu3O7 samples were deformed under high pressure–high temperature (HP–HT) conditions (P?=?2?GPa, T?=?900 and 800°C, t?=?15?min). During the HP–HT treatment, samples were in contact with annealed zirconia, preventing oxygen loss, in such a way that the orthorhombic superconductor phase was preserved at the end of the experiment. The deformed microstructure, investigated by transmitted electron microscopy, exhibited original features characterized by a very low twin density, a memory effect on the dislocations shape and a non-classical faulted loops distribution in the matrix. A mechanism, based on the interaction between twin and gliding dislocations, is proposed to explain the nucleation of these aligned loops.  相似文献   

2.
Holistic processing (HP) of faces is usually measured by the composite effect. While Weston and Perfect [2005. Effects of processing bias on the recognition of composite face halves. Psychonomic Bulletin & Review, 12, 1038–1042. doi:10.3758/BF03206440] found that priming at the local level speeded recognition of components of faces, Gao et al. [2011. Priming global and local processing of composite faces: Revisiting the processing-bias effect on face perception. Attention Perception & Psychophysics, 73, 1477–1486. doi:10.3758/s13414-011-0109-7] found that only global priming had an effect on HP of faces. The two studies used different versions of the composite task (the partial design, which is considered to be prone on bias, and the complete design). However, the two studies also differed in other respects and it is difficult to know to what extent issues with the partial design contributed to the differing conclusions. In the present study, the HP indexed by the complete design measure was augmented by global priming. In contrast, no effect was observed in the partial design index. We claim that the partial design index reflects other factors besides HP, including response bias, and conclude that HP can be understood within the context of domain-general attentional processes.  相似文献   

3.
The goal of this research was to examine passion as a determinant of mindfulness. Three studies were conducted based on the premise that harmonious passion (HP) provides access to adaptive self-processes, such as mindfulness, whereas obsessive passion (OP) limits such access. In Study 1 (n = 301), results revealed that HP and OP positively and negatively predicted mindfulness, respectively. Study 2 (n = 459) aimed at replicating results from Study 1 and explored the mediating role of mindfulness in the passion–affect relationship. Results uncovered that HP and OP, respectively, predicted positively and negatively mindfulness that, in turn, positively predicted positive affect and negatively predicted negative affect. These results were replicated in Study 3 (n = 176) while incorporating a time lag in the design. Vitality was also included in the model and was positively predicted by mindfulness. Findings underscore the facilitative role of HP in accessing adaptive self-processes, such as mindfulness.  相似文献   

4.
The emergence of Gaussian model‐based partitioning as a viable alternative to K‐means clustering fosters a need for discrete optimization methods that can be efficiently implemented using model‐based criteria. A variety of alternative partitioning criteria have been proposed for more general data conditions that permit elliptical clusters, different spatial orientations for the clusters, and unequal cluster sizes. Unfortunately, many of these partitioning criteria are computationally demanding, which makes the multiple‐restart (multistart) approach commonly used for K‐means partitioning less effective as a heuristic solution strategy. As an alternative, we propose an approach based on iterated local search (ILS), which has proved effective in previous combinatorial data analysis contexts. We compared multistart, ILS and hybrid multistart–ILS procedures for minimizing a very general model‐based criterion that assumes no restrictions on cluster size or within‐group covariance structure. This comparison, which used 23 data sets from the classification literature, revealed that the ILS and hybrid heuristics generally provided better criterion function values than the multistart approach when all three methods were constrained to the same 10‐min time limit. In many instances, these differences in criterion function values reflected profound differences in the partitions obtained.  相似文献   

5.
In order to obtain comprehensive performance, heavy elements were added into superalloys for solid-solution hardening. It is found that, rather than adopting random distributions, the heavy atoms prefer to form short-range ordered columns with heavy-element stripes 1–2 nm in length. This is supported by our ab initio calculations. Owing to the strong bonding strength between the refractory elements and nickel atoms, this short-range ordering may be beneficial to the mechanical performances of superalloys.  相似文献   

6.
The mechanical behaviour of polycrystalline hexagonal close-packed cobalt was investigated over a large range of grain size d in order to examine the occurrence of size effects. Crystallographic texture and amount of face centred cubic allotropic phase were maintained unchanged thanks to appropriate heat treatment procedures. The Hall–Petch (HP) relation exhibits two distinct behaviours from the very beginning of plastic strain levels. The conventional HP law is fulfilled for a number of grains across the thickness t higher than a critical value (t/d)c = 14. For t/d lower than (t/d)c, a multicrystalline regime is evidenced highlighting a strong reduction in flow stress. The high value of (t/d)c is related to the low-stacking fault energy of cobalt in the basal plane. The size effect is predominant in the first work hardening stage where slip mechanisms and stacking faults predominate. In the second stage, driven by mechanical twinning processes, this effect is less sensitive. Finally, the size effect could also affect the end of the elastic stage, in link with nonlinear elasticity mechanisms.  相似文献   

7.
In this paper implicit function-based parameterizations for orthogonal and oblique rotation matrices are proposed. The parameterizations are used to construct Newton algorithms for minimizing differentiable rotation criteria applied to m factors and p variables. The speed of the new algorithms is compared to that of existing algorithms and to that of Newton algorithms based on alternative parameterizations. Several rotation criteria were examined and the algorithms were evaluated over a range of values for m. Initial guesses for Newton algorithms were improved by subconvergence iterations of the gradient projection algorithm. Simulation results suggest that no one algorithm is fastest for minimizing all criteria for all values of m. Among competing algorithms, the gradient projection algorithm alone was faster than the implicit function algorithm for minimizing a quartic criterion over oblique rotation matrices when m is large. In all other conditions, however, the implicit function algorithms were competitive with or faster than the fastest existing algorithms. The new algorithms showed the greatest advantage over other algorithms when minimizing a nonquartic component loss criterion.  相似文献   

8.
In the field of psychology, the practice ofp value null-hypothesis testing is as widespread as ever. Despite this popularity, or perhaps because of it, most psychologists are not aware of the statistical peculiarities of thep value procedure. In particular,p values are based on data that were never observed, and these hypothetical data are themselves influenced by subjective intentions. Moreover,p values do not quantify statistical evidence. This article reviews thesep value problems and illustrates each problem with concrete examples. The three problems are familiar to statisticians but may be new to psychologists. A practical solution to thesep value problems is to adopt a model selection perspective and use the Bayesian information criterion (BIC) for statistical inference (Raftery, 1995). The BIC provides an approximation to a Bayesian hypothesis test, does not require the specification of priors, and can be easily calculated from SPSS output.  相似文献   

9.
According to prospect theory, individuals are risk averse regarding gains but risk seeking regarding losses, implying an S-shaped value function. The S-shaped value function hypothesis is based on experiments in which subjects are asked to choose separately between alternatives with either only positive or only negative outcomes, alternatives which rarely exist in the capital market. In addition, the S-shaped findings may be biased by the “certainty effect” and by probability distortion. In this paper we employ the recently developed prospect stochastic dominance criterion to test the prospect theory S-shaped value function hypothesis with mixed outcomes and with no “certainty effect.” Assuming that subjects do not distort moderate probabilities, we strongly reject the prospect theory S-shaped value function, with at least 76–86% of the choices being inconsistent with such preferences. When possible subjective probability distortions are taken into account, we find that at least 50–66% of the choices are inconsistent with an S-shaped value function.  相似文献   

10.
In the literature on the measurement of change,reliable change is usually determined by means of a confidence interval around an observed value of a statistic that estimates thetrue change. In recent literature on the efficacy of psychotherapies, attention has been particularly directed at the improvement of the estimation of the true change. Reliable Change Indices, incorporating thereliability-weighted measure of individual change, also known as Kelley's formula, have been proposed. According to current practice, these indices are defined as the ratio of such an estimator and an intuitively appealing criterion and then regarded as standard normally distributed statistics. However, because the authors fail to adopt an adequate standard error of the estimator, the statistical properties of their indices are unclear. In this article, it is shown that this can lead to paradoxical conclusions. The adjusted standard error is derived.  相似文献   

11.
This meta‐analysis reviewed 192 scholarly works from 1993 to 2013 using the Beck Anxiety Inventory (Beck & Steer, 1993 ). Aggregated internal consistency (coefficient alpha) was .91 (k = 117), and test–retest reliability was .65 (k = 18). Convergent comparisons were robust across 33 different anxiety instruments and the Beck Depression Inventory–II (Beck, Steer, & Brown, 1996 ). Structural validity primarily supported the original 2‐factor solution proposed by Beck and Steer ( 1993 ), and diagnostic accuracy varied according to the sample size and criterion cutoff score.  相似文献   

12.
The neo-Fregean account of arithmetical knowledge is centered around the abstraction principle known as Hume’s Principle: for any concepts X and Y, the number of X’s is the same as the number of Y’s just in case there is a 1–1 correspondence between X and Y. The Caesar Problem, originally raised by Frege in §56 of Die Grundlagen der Arithmetik, emerges in the context of the neo-Fregean programme, because, though Hume’s Principle provides a criterion of identity for objects falling under the concept of Number–namely, 1–1 correspondence—the principle fails to deliver a criterion of application. That is, it fails to deliver a criterion that will tell us which objects fall under the concept Number, and so, leaves unanswered the question whether Caesar could be a number. Hale and Wright have recently offered a neo-Fregean solution to this problem. The solution appeals to the notion of a categorical sortal. This paper offers a reconstruction of their solution, which has the advantage over Hale and Wright’s original proposal of making clear what the structure of the background ontology is. In addition, it is shown that the Caesar Problem can be solved in a framework more minimal than that of Hale and Wright, viz. one that dispenses with categorical sortals. The paper ends by discussing an objection to the proposed neo-Fregean solutions, based on the idea that Leibniz’s Law gives a universal criterion of identity. This is an idea that Hale and Wright reject. However, it is shown that a solution very much in keeping with their own proposal is available, even if it is granted that Leibniz’s Law provides a universal criterion of identity.
Nikolaj Jang PedersenEmail:
  相似文献   

13.
In hidden‐profile (HP) problems, groups squander their potential to make superior decisions because members fail to capitalize on each other's unique knowledge (unshared information). A new self‐regulation perspective suggests that hindrances in goal striving (e.g., failing to seize action opportunities) contribute to this problem. Implementation intentions (if–then plans) are known to help deal with hindrances in goal striving; therefore, supporting decision goals with if–then plans should improve the impact of unshared information on group decisions. Indeed, in line with past research, control participants in two experiments rarely identified the best alternative despite monetary incentives and setting decision goals. In contrast, simply adding if–then plans to review advantages of the non‐preferred alternatives before making the final decision significantly increased solution rates. Process manipulations (Experiment 1) and measures (Experiment 2) indicate that conceptualizing HP problems as a self‐regulation challenge provides explanatory power beyond existing accounts. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

14.
There are two main classes of model of interference effects in recognition memory: item-noise and context-noise. Item-noise models predict that a loss of memory discriminability will occur with an increase in the number of studied items from the same taxonomic category (category length, CL) and that forced-choice recognition performance will be higher when the target and lure are related rather than unrelated. Context-noise models, however, predict null effects for both of these manipulations. Although results from some recent experiments suggest that CL and target–lure relatedness have a trivial or no effect on memory discriminability when the related items from the same taxonomic category are “not back to back in the study list but are separated (spaced) by interleaving items from other semantic categories,” these experiments have methodological limitations that were eliminated in the present experiment in which exemplars representing category lengths of 2, 8, or 14 were presented spaced apart within the same study list. Recognition was tested using a yes/no recognition test or a two-alternative forced-choice recognition test in which the target and lure were either related or unrelated. In yes/no recognition, d′ decreased as CL increased, replicating prior research. However, when the slope of the z-ROC function is less than 1.0, as is typically so and was so in the present results, d′ differences can arise due to criterion shifts and are not necessarily due to memory discriminability differences. When the more appropriate measure of memory discriminability, d a , was computed, CL had no effect in yes/no recognition, nor did it have an effect in forced-choice recognition, which also was not affected by target–lure relatedness. Thus, the present results are congruent with context-noise models and pose a challenge for item-noise models.  相似文献   

15.
A value structure based on the Tchebycheff measure is proposed to assess the worst-case and average errors in bicriteria heuristics. This analysis builds on earlier results for additive value structures (Daniels, R. L., Manag. Sci., 38 , 501–513 (1992)). The significance of the Tchebycheff measure is that it is representative of a class of quasi-concave functions, and analysis based on this measure is indicative of the performance of the heuristic over a broad range of preference value structures. © 1998 John Wiley & Sons, Ltd.  相似文献   

16.
It is shown that initially sharp interface in AB diffusion couple, above the ordering temperature, can shift with anomalous kinetics, i.e. deviations from the parabolic growth kinetics are possible. The initial slopes of the shift versus time functions can be even unity for large diffusion asymmetry (the ratio of diffusion coefficients of the parent materials in orders of magnitude) and gradually decrease to 0.5 at larger distances (longer times). This is in accordance with earlier results obtained in phase separating systems. It is shown that from the results of simulations the crossover thickness, X*, between the linear and parabolic regimes can also be calculated, and the applicability of the linear–parabolic law is confirmed. Furthermore, it is illustrated that the crossover thickness depends exponentially on the diffusion asymmetry parameter, with the exponent close to the value obtained from analytical estimations.  相似文献   

17.
The aim of this study was to examine how six different types of situational judgment test (SJT) instructions, used frequently in practice, influence the psychometric characteristics of SJTs. The six SJT versions used the exact same items and differed only in their instructions; these versions were administered in two phases. Phase I was a between–subjects design (n= 486) that had participants complete one version of the SJTs. Phase II was a within–subjects design (n= 231) held several weeks later that had participants complete all six versions of the SJTs. Further, 146 of these individuals completed both phases, allowing for an assessment of test–retest reliability. A variety of objective and subjective criteria were collected, including self and peer ratings. Results indicated that instructions had a large effect on SJT responses, reliability, and validity. In general, instructions asking what one ‘would do’ showed more favorable characteristics than those that asked what one ‘should do’. Correlations between these two types were relatively low despite the fact that the same items were used, and criterion–related validities differed substantially in favor of the ‘would do’ instructions. Overall, this study finds that researchers and practitioners must give careful consideration to the types of SJT instructions used; failing to do so could influence criterion–related validity and cloud inferences of construct validity.  相似文献   

18.
Matthias Schirn 《Synthese》2006,148(1):171-227
In this paper, I shall discuss several topics related to Frege’s paradigms of second-order abstraction principles and his logicism. The discussion includes a critical examination of some controversial views put forward mainly by Robin Jeshion, Tyler Burge, Crispin Wright, Richard Heck and John MacFarlane. In the introductory section, I try to shed light on the connection between logical abstraction and logical objects. The second section contains a critical appraisal of Frege’s notion of evidence and its interpretation by Jeshion, the introduction of the course-of-values operator and Frege’s attitude towards Axiom V, in the expression of which this operator occurs as the key primitive term. Axiom V says that the course-of-values of the function f is identical with the course-of-values of the function g if and only if f and g are coextensional. In the third section, I intend to show that in Die Grundlagen der Arithmetik (1884) Frege hardly could have construed Hume’s Principle (HP) as a primitive truth of logic and used it as an axiom governing the cardinality operator as a primitive sign. HP expresses that the number of Fs is identical with the number of Gs if and only if F and G are equinumerous. In the fourth section, I argue that Wright falls short of making a convincing case for the alleged analyticity of HP. In the final section, I canvass Heck’s arguments for his contention that Frege knew he could deduce the simplest laws of arithmetic from HP without invoking Axiom V. I argue that they do not carry conviction. I conclude this section by rejecting an interpretation concerning HP suggested by MacFarlane.  相似文献   

19.
Abstract

Previous studies have shown important effects of stress on decision making (DM). In addition, individuals differ in their relative activation of the left and right hemispheres (hemispheric preference; HP), with possible implications for DM. This study tested the relationship between stress, HP and their interaction, with DM in managers. We included a sample of 114 managers from Israel, Italy and France. Stress was inversely and significantly related to DM thoroughness (r=?.333), left-HP (r=?.24) and was positively correlated with instinctiveness DM (r=.25; all p<.05). Importantly, a stress×HP interaction accounted for an additional and significant 9% of the variance in thoroughness, beyond their main effects, nationality and gender. In this interaction, only in right HP managers, but not in left HP managers, stress was inversely correlated with thoroughness. A stress×HP interaction was not found for instinctiveness. Theoretically, our results advise investigating both situational (stress) and personal or biological (HP) factors in the job stress field. Practically, it can guide stress specialists to whom to provide scarce counseling resources of stress management, to improve workers’ DM and well-being.  相似文献   

20.
In this paper, I defend the view that the values of concrete objects and persons are reducible to the final values of tropes. This reductive account has recently been discussed and rejected by Rabinowicz and R0nnow‐Rasmussen (2003). I begin by explaining why the reduction is appealing in the first place. In my rejoinder to Rabinowicz and R0nnow‐Rasmussen I defend trope‐value reductionism against three challenges. 1 focus mainly on their central objection, that holds that the reduction is untenable since different evaluative attitudes have, ontologically speaking, different objects. I grant that this may well be so, but argue that the objection is based on an unwarranted, loose reading of the notion ‘value for its own sake’. On the more reasonable strict reading, it is plausible to maintain that tropes are the sole ontological category that can properly be ascribed final value.  相似文献   

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