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91.
We construct a faithful interpretation of ukasiewicz's logic in product logic (both propositional and predicate). Using known facts it follows that the product predicate logic is not recursively axiomatizable.We prove a completeness theorem for product logic extended by a unary connective of Baaz [1]. We show that Gödel's logic is a sublogic of this extended product logic.We also prove NP-completeness of the set of propositional formulas satisfiable in product logic (resp. in Gödel's logic). 相似文献
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Augusto Palmonari Erich Kirchler Maria Luisa Pombeni 《European journal of social psychology》1991,21(5):381-402
Adolescents from three Italian cities responded to a questionnaire concerning the particular peer-group with which they were associated and identification with their family, aspects of the process of coping with seven developmental tasks, and demographic characteristics. The participants were 1600 male and female teenagers, with a mean age of 16.28 years, who were approached at schools and various meeting places in three Italian cities. The study shows that effective coping with developmental tasks depends largely on the degree of identification with both family and peer-group. Those who identify with both social groupings show advantages in various critical situations. Adolescents only identifying with either family or peers get emotional and instrumental support from that group but not from the other, thus, they are supported in some critical situations but not in others. Adolescents who are unwilling or unable to identify with their family and/or their peers are less successful in managing the transition to adulthood than others who are close to their parents and peers. Consistent with the findings of previous studies, the type of group adolescents join, be it a formal group or an informal street group, has no significant effect on their coping strategies. 相似文献
95.
Analysis of 1998 statistics for individual performance in the PGA European Tour yielded significant differences between some shot-making skills (drive distance, total driving, greens in regulation, and sand saves) between the top 10 and bottom 10 money winners, replicating (with partially different results) a result found for the 1995 American PGA Tour by Engelhardt. 相似文献
96.
Sayaka Kawarai Anthony Hernández Mitch J. Fryling 《Child & family behavior therapy》2017,39(3):191-199
As the cultural dynamic continues to become increasingly complex, it is critical to assess cultural factors that influence practice. The present study considers the treatment preferences of Japanese mothers of children with developmental disabilities. After answering demographic questions, each participant was given four scenarios and asked how they would respond by choosing one of four interventions (differential reinforcement, ignoring, reprimanding, and time-out). Overall, we found that parents preferred differential reinforcement strategies the most. Moreover, parents who reported that their children had a history of involvement with applied behavior analysis were especially likely to choose differential reinforcement. Implications for future research and practice are provided. 相似文献
97.
By atomic-scale high-angle annular dark-field scanning transmission electron microscopy, the long-period stacking ordered (LPSO) structures in a near-equilibrium Mg97Zn1Y2 (at.%) alloy have been characterised. In addition to 18R and 14H, new polytypes of LPSO structures are analysed and determined as 60R, 78R, 26H, 96R, 38H, 40H, 108H and 246R. All of these LPSO structures feature AB′C′A building blocks with two Mg layers and three Mg layers sandwiched between them. The Bravais lattices and space groups of new polytypes of LPSO structures were easily determined via the newly introduced method. A structural relationship between the LPSOs is proposed. 相似文献
98.
Eva Landová Kateřina Hotová Svádová Roman Fuchs Pavel Štys Alice Exnerová 《Animal cognition》2017,20(5):855-866
Social learning plays an important role in acquiring new foraging skills and food preferences in many bird species but its potential role in learning to avoid aposematic prey has never been studied. We tested the effect of social learning on the acquisition of avoidance of aposematic insect prey (firebug Pyrrhocoris apterus; Heteroptera) in juvenile, hand-reared great tits (Parus major). Behaviour towards aposematic prey was compared between two groups of birds: (1) the observers that were, prior to encounter with firebugs, allowed to watch the experienced conspecific demonstrator repeatedly refuse to attack the prey, and (2) the control birds that lacked this opportunity. Observing an experienced demonstrator was not sufficient for learning complete avoidance, because birds from both groups attacked at least the first firebug they had encountered in avoidance training. However, the opportunity to observe the avoidance behaviour of another bird significantly increased the rate of subsequent individual learning of observers in comparison with control birds. Social learning also decreased mortality of firebugs killed by the birds during the avoidance learning. Socially enhanced learning to avoid aposematic prey might be a mechanism important especially for naive juvenile birds learning from their parents, but it could also enhance learning in adults from their more experienced flock mates. Because social learning of avoidance may also lead to decreased mortality of aposematic prey, its effect should be taken into account in scenarios considering evolution and maintenance of prey warning signals. 相似文献
99.
Damian Scarf Michael C. Corballis Onur Güntürkün Michael Colombo 《Animal cognition》2017,20(5):999-1002
Many children pass through a mirror stage in reading, where they write individual letters or digits in mirror and find it difficult to correctly utilize letters that are mirror images of one another (e.g., b and d). This phenomenon is thought to reflect the fact that the brain does not naturally discriminate left from right. Indeed, it has been argued that reading acquisition involves the inhibition of this default process. In the current study, we tested the ability of literate pigeons, which had learned to discriminate between 30 and 62 words from 7832 nonwords, to discriminate between words and their mirror counterparts. Subjects were sensitive to the left–right orientation of the individual letters, but not the order of letters within a word. This finding may reflect the fact that, in the absence of human-unique top-down processes, the inhibition of mirror generalization may be limited. 相似文献
100.
Fanny-Linn Kraft Tereza Forštová A. Utku Urhan Alice Exnerová Anders Brodin 《Animal cognition》2017,20(6):1049-1057
Self-recognition is a trait presumed to be associated with high levels of cognition and something previously considered to be exclusive to humans and possibly apes. The most common test of self-recognition is the mark/mirror test of whether an animal can understand that it sees its own reflection in a mirror. The usual design is that an animal is marked with a colour spot somewhere on the body where the spot can only be seen by the animal by using a mirror. Very few species have passed this test, and among birds, only magpies have been affirmatively demonstrated to pass it. In this study, we tested great tits (Parus major), small passerines, that are known for their innovative foraging skills and good problem-solving abilities, in the mirror self-recognition test. We found no indication that they have any ability of this kind and believe that they are unlikely to be capable of this type of self-recognition. 相似文献