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1.
Suppes (1969, Journal of Mathematical Psychology, 6) apparently proved that any finite automaton could be mimicked by the asymptotic behavior of a stimulussampling S?R model, broadly implying that cognitive theory could be reduced to S?R theory. Here it is shown that the finite automata used by Suppes are more restricted and less powerful than finite automata in general. Furthermore, the S?R models proposed by Suppes are limited to producing the behavior of only these restricted automata, and cannot mimic all finite automata. Hence, the formal claim that S?R models are adequate to produce all behaviors obtainable from finite automata, and the informal claim that cognitive theory reduces to S?R theory, do not follow from Suppes's (1969) result. Some alternative S?R models and their problems are also briefly discussed.  相似文献   

2.
3.
Empathy reduces aggressive behavior. While empathy and social intelligence are strongly correlated, it is, for both logical and consequential reasons, important to regard them as different concepts. Social intelligence is required for all types of conflict behavior, prosocial as well as antisocial, but the presence of empathy acts as a mitigator of aggression. When empathy is partialed out, correlations between social intelligence and all types of aggression increase, while correlations between social intelligence and peaceful conflict resolution decrease. Social intelligence is related differently to various forms of aggressive behavior: more strongly to indirect than to verbal aggression, and weakest to physical aggression, which is in accordance with the developmental theory of aggressive style. More sophisticated forms of aggression require more social intelligence.  相似文献   

4.
Eight pigeons were run on a one-key, discrete-trials observing procedure. Pecks during a trial produced S+ and S?, colored key lights which signalled whether the trial would end with response-independent grain reinforcement or nonreinforcement. S+ and S? were produced on a VI schedule which began operating at the onset of the trial. In the main experimental condition, only a response preceded by at least 6 sec of nonresponding could produce S? on nonreinforced trials; any response which satisfied the VI requirement produced S+ on reinforced trials. This procedure allowed the birds to produce S+ on reinforced trials with or without producing S? on nonreinforced trials. The subjects learned to produce fewer S?s over sessions, indicating that S? had a punishing effect on observing. The results were taken as evidence for the conditioned reinforcement hypothesis of observing and against the uncertainty reduction hypothesis.  相似文献   

5.
Abstract

The electrical resistivity of bulk semiconducting amorphous TlxSe100?x alloys with 0 ≤ x ≤ 25 has been investigated up to a pressure of 14 GPa and down to liquidnitrogen temperature by use of a Bridgman anvil device. All the glasses undergo a discontinuous pressure-induced semiconducting-to-metal transition. X-ray diffraction studies on the pressure-recovered samples show that the high-pressure phase is the crystalline phase. The pressure-induced crystalline products are identified to be a mixture of Se having a hexagonal structure with a = 4·37 Å and c = 4·95 Å and TlSe having a tetragonal structure with a = 8·0 Å and c = 7·0 Å  相似文献   

6.
Tin whisker growth has been observed on the surface of bulk Sn–Nd alloys with Nd contents of 30, 5 and 0.5 wt%, under ambient conditions of temperature and atmosphere. It is shown that the whiskers originate from the area of Sn–Nd intermetallic compounds after a very short incubation period and that they exhibit a relatively high growth rate on the surface of the bulk alloys. The results show that these Sn-based, rare-earth alloys have a very strong propensity to grow tin whiskers, i.e. this rare-earth element in tin is a catalytic agent for whisker growth. Direct evidence is also shown that whiskers can grow from the surface of a bulk Sn-based alloy.  相似文献   

7.
Helium generated in materials by the nuclear reaction (n,?α) is generally considered to be harmful. It is well-known that helium prompts not only the nucleation of interstitial-type dislocation loops, but also the nucleation of voids in metals and alloys irradiated with high-energy particles, which degrades their mechanical properties. In this study, however, we find that helium trapped by dislocations in Ni increases both the ultimate tensile strength and total elongation.  相似文献   

8.
The purpose of this investigation was to assess the relative effectiveness of two prompt-fading procedures for teaching difficult visual discriminations to autistic children. Both prompt procedures involved within-stimulus fading where manipulation occurred on the relevant component of the discrimination. One procedure involved fading first along the S+ stimulus, while holding the S? stimulus constant. The other procedure involved fading first along the S? stimulus, while holding the S+ stimulus constant. Eight autistic children were each taught two discriminations, one by each of the prompt procedures. Results indicated that for all but one child, the discriminations were acquired significantly faster, with fewer errors, when the S+ stimulus was faded first. These findings are related to the literature on the effects of stimulus novelty on selection and learning.  相似文献   

9.
Abstract

A defect-induced peak at 328 cm?1 in the infrared absorption spectrum of type Ia diamonds is confirmed to belong with the other absorptions (in particular, the B′ localised mode near 1370 cm?1 and the D component of the lattice vibrations) which are associated with the {100} platelets found in these crystals. It is suggested that this absorption and other weaker absorptions found in its vicinity may be due to the bending vibrations of atomic bonds in the platelets.  相似文献   

10.
Abstract

Thin-foil transmission electron microscopy specimens of orthorhombic YBa2Cu3O7?x subjected to residual elastic strains have shown slow crack growth in an atmosphere with low moisture content. Microcracks, initiated by amorphization at the strained edges, propagate alternately along (110) twin boundaries and (001) stacking faults, where strain energy is accumulated locally. The formation of carbon-rich amorphous layers along the strained lattice planes, followed by residual stress-assisted crack propagation, resembles stress-corrosion cracking in this ceramic superconductor.  相似文献   

11.
Famously, Frank P. Ramsey suggested a test for the acceptability of conditionals. Recently, David Chalmers and Alan Hájek (2007) have criticized a qualitative variant of the Ramsey test for indicative conditionals. In this paper we argue for the following three claims: (i) Chalmers and Hájek are right that the variant of the Ramsey test that they attack is not the correct way of spelling out an acceptability test for indicative conditionals. But there is a suppositional variant of the Ramsey test which is still stated in purely qualitative terms, which avoids the problems, and which looks correct. (ii) While the variant of the Ramsey test that Chalmers and Hájek criticize is not correct, it is still a good approximation of a correct formulation of the Ramsey test which may be usefully employed in various contexts. (iii) The variant of the Ramsey test that Chalmers and Hájek suggest as a substitute for the deficient version of the Ramsey test is itself subject to worries similar to those raised by Chalmers and Hájek, if it is given a non-suppositional interpretation.  相似文献   

12.
Thin films of Ga x Te100? x (x?=?3, 6, 9 and 12) have been synthesized by thermal evaporation. From SEM images, it is observed that all the films contain nanoparticles of sizes varying from 100 to 200?nm. The dc electrical conductivity of the as-deposited films of Ga x Te100?x nanoparticles is measured as a function of temperature range from 298 to 383?K, and increases exponentially with temperature. The value of the activation energy, calculated from the slope of ln?σ dc versus 1000/T plots, is found to decrease with increase in the Ga content. On the basis of the value of the pre-exponential factor σ o, it is suggested that the conduction is due to thermally assisted tunneling of carriers in localized states near the band edges. The optical measurements suggest an indirect optical band gap in this system. The value of the optical band gap decreases on increasing the Ga concentration.  相似文献   

13.
The paper describes the genesis, construction and preliminary reliability testing of the Parent?Infant Relational Assessment Tool (PIRAT). PIRAT is a clinical assessment tool for the identification of risk in the early parent?infant relationship. The rationale was to design a flexible, reliable measure that would enable professionals working with infants and their caregivers to assess the parent?infant relationship as it appears in the consulting room, clinic or home environment and to pinpoint areas of concern at the earliest possible opportunity. The measure was developed in the Parent–Infant Project at the Anna Freud Centre and a subsequent study was undertaken to establish whether it could be successfully transferred to healthcare professionals for use in their workplace settings. A reliability study was conducted with a panel of health professionals, including midwives, health visitors, child protection social workers and clinical psychologists, using videotapes of their consultations in the home or clinic with mothers and infants of 0?2 years old. The results demonstrate good interrater reliability for the 10 participants in the study. Verbatim excerpts from the training sessions are included to elucidate the process of training and the ways in which participants engaged with and embedded the measure into their practice.  相似文献   

14.
The present studies assessed the degree of stimulus control exerted by S+ and S? without confoundings of stimulus novelty and stimulus ambiguity. In Experiment 1, rats were trained on two intercurrent simultaneous discrimination problems with nine times more training given on one than the other. Then the animals were given transfer tests with re-paired stimuli. The results showed that S? exerts greater stimulus control than S+ in a two-choice simultaneous discrimination. Experiment 2 provided a test of the possibility that the relative degree of control by S? varies with different amounts of training. Three groups were trained on two intercurrent simultaneous discrimination problems; each group was given 7, 11, or 15 times more training on one problem than the other. Then transfer tests were given with re-paired stimuli. Again the results showed that S? exerts greater stimulus control than S+ in a two-choice simultaneous discrimination.  相似文献   

15.
When observing a novel action, infants pay attention to the model’s constraints when deciding whether to imitate this action or not. Gergely et al. (2002) found that more 14-month-olds copied a model’s use of her head to operate a lamp when she used her head while her hands were free than when she had to use this means because it was the only means available to her (i.e., her hands were occupied). The perceptional distraction account (Beisert et al., 2012) claims that differences between conditions in terms of the amount of attention infants paid to the modeled action caused the differences in infants’ performance between conditions. In order to investigate this assumption we presented 14-month-olds (N = 34) with an eye-tracking paradigm and analyzed their looking behavior when observing the head-touch demonstration in the two original conditions. Subsequently, they had the chance to operate the apparatus themselves, and we measured their imitative responses. In order to explore the perceptional processes taking place in this paradigm in adulthood, we also presented adults (N = 31) with the same task. Apart from the fact that we did not replicate the findings in imitation with our participants, the eye-tracking results do not support the perceptional distraction account: infants did not statistically differ − not even tendentially − in their amount of looking at the modeled action in both conditions. Adults also did not statistically differ in their looking at the relevant action components. However, both groups predominantly observed the relevant head action. Consequently, infants and adults do not seem to attend differently to constrained and unconstrained modelled actions.  相似文献   

16.
Nitridoferrates containing monovalent iron ions are a class of materials of recent interest as potentially novel magnetic materials. Aiming at the exploration of nitridoferrates of calcium, we report the single crystal growth from Ca ?ux and crystal structure of the first member (n?=?2) of a series of inverse Ruddlesden-Popper nitrides with a general formula of An?1A'2BnX3n+1, where A?=?Li/Fe, A'?=?Te, B?=?N, and X?=?Ca. Single crystal X-ray diffraction analyses indicate the crystal with a composition of Ca7(Li0.32(1)Fe0.68(1))Te2N2 and the tetragonal space group I4/mmm (a?=?4.7884(1) Å, c?=?25.3723(4) Å, Z?=?2). The structure features alternately stacking NaCl-type A'X slabs and the perovskite-type ABX3 slabs along the c axis. The Li/Fe atoms are located in cuboctahedral cavities surrounded by eight Ca6N octahedra in the ABX3 slab. This work demonstrates the viability of the Ca-rich ?ux as a suitable solvent for the exploration of new complex nitrides with interesting crystal structure and properties.  相似文献   

17.
After reviewing some of the unique ecumenical steps taken by Pope Francis, this article examines briefly the three ecumenical paragraphs in Evangelii Gaudium. It presents them in the wider context of this post-synodal exhortation, of the ecumenical gestures and testimonies of Pope Francis, the ecumenical orientation of the Catholic Church and the ecumenical movement as such. It concludes with an outlook on a newly emerging ecumenical paradigm.  相似文献   

18.
Two types of twin boundaries in superconductor Y0.6Na0.4Ba2Cu2.7Zn0.3O7? δ , the cation-centered and oxygen-centered types, and the associated twinning dislocation have been studied by high-resolution electron microscopy. The structure map projected in the [001] direction was obtained from a single image by means of the image deconvolution technique. In this map, all columns of metallic atoms appear as individual black dots, and hence the two types of twin boundaries are distinguished from each other at atomic level. It is seen that the twinning dislocation occurs when the two types of twin boundaries meet each other. The structure model of the twinning dislocation together with the two types of twin boundaries has been derived straightforwardly based on the positions of black dots seen in the deconvoluted image.  相似文献   

19.
The glass-forming ability of Ge1? x Sn x Se2.5 (0 ≤ x ≤ 0.5) alloys was studied using differential scanning calorimetry. Samples were scanned at different heating rates under non-isothermal conditions. Various simple quantitative methods were employed to assess the stability of the glassy materials in the above-mentioned system. All of these methods are based on characteristic temperatures, such as the glass-transition temperature, T g, the onset-of-crystallization temperature, T c, and the peak crystallization temperature, T p. A crystallization rate factor, K, has also been used as a measure of the thermal stability of the glasses. It was found that Ge0.7Sn0.3Se2.5 was the least stable among all the samples.  相似文献   

20.
Perovskite manganite nanoparticles with the chemical formula La0.67Sr0.33Mn1?xZnxO3 (x = 0, 0.1 and 0.2) were prepared by the sol–gel process and the influence of Zn substitution on their microstructural and magnetic properties studied in detail. X-ray diffractometry (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed for crystal structure determination and microstructural analysis. The results of XRD analysis confirmed the polycrystalline nature and rhombohedral crystal structure with space group R(-3c) for all compositions. SEM micrographs of the samples revealed an agglomeration/well-connected appearance of the particles. The composition and uniform distribution of all the elements were established by energy-dispersive spectroscopy. TEM images clearly confirmed an almost spherical shape of the nanoparticles with an average particle size of about 11, 14 and 13 nm for the 0, 10 and 20% Zn-doped samples, respectively. The magnetic behaviour of the nanoparticles was studied at room temperature with a vibrating sample magnetometer (VSM) up to a field of 1.8 Tesla. These measurements established a superparamagnetic nature with a variation in the saturation magnetization (Ms) with Zn content.  相似文献   

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