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231.
I. Janioka-Żuk 《Studia Logica》1980,39(4):415-423
LetN. be the set of all natural numbers (except zero), and letD n * = {k ∈N ∶k|n} ∪ {0} wherek¦n if and only ifn=k.x f or somex∈N. Then, an ordered setD n * = 〈D n * , ? n , wherex? ny iffx¦y for anyx, y∈D n * , can easily be seen to be a pseudo-boolean algebra. In [5], V.A. Jankov has proved that the class of algebras {D n * ∶n∈B}, whereB =,{k ∈N∶ ? \(\mathop \exists \limits_{n \in N} \) (n > 1 ≧n 2 k)is finitely axiomatizable. The present paper aims at showing that the class of all algebras {D n * ∶n∈B} is also finitely axiomatizable. First, we prove that an intermediate logic defined as follows: $$LD = Cn(INT \cup \{ p_3 \vee [p_3 \to (p_1 \to p_2 ) \vee (p_2 \to p_1 )]\} )$$ finitely approximatizable. Then, defining, after Kripke, a model as a non-empty ordered setH = 〈K, ?〉, and making use of the set of formulas true in this model, we show that any finite strongly compact pseudo-boolean algebra ? is identical with. the set of formulas true in the Kripke modelH B = 〈P(?), ?〉 (whereP(?) stands for the family of all prime filters in the algebra ?). Furthermore, the concept of a structure of divisors is defined, and the structure is shown to beH D n * = 〈P (D n * ), ?〉for anyn∈N. Finally, it is proved that for any strongly compact pseudo-boolean algebraU satisfying the axiomp 3∨ [p 3→(p1→p2)∨(p2→p1)] there is a structure of divisorsD * n such that it is possible to define a strong homomorphism froomiH D n * ontoH D U . Exploiting, among others, this property, it turns out to be relatively easy to show that \(LD = \mathop \cap \limits_{n \in N} E(\mathfrak{D}_n^* )\) . 相似文献
232.
Lynn L. Peterson Kent O. Dana Joan S. Reisch Thomas Hibberd Maurice Korman Paul I. Munves Alvin J. North Thomas A. Van Hoose Frank Trimboli 《Behavior research methods》1981,13(4):485-498
An information processing system for a psychiatric emergency room is described. Several studies are presented that show the utility of the system. In the first study, variables involved in diagnosis are explicated. The second study attempts to determine the characteristics that distinguish recidivists from nonrecidivists at an emergency room. The third study attempts to find patient variables related to success in short-term treatment programs. The final study is aimed at discovering whether there are psychopathological effects related to the use of inhalants. Together, these studies show the potential of a mental health information system for learning more about the nature of mental disorders and their treatment. 相似文献
233.
I Rock D Smith 《Journal of experimental psychology. Human perception and performance》1981,7(1):19-29
It has been assumed that certain stimulus transformations lead directly to depth effects, that is, that such transformations are the necessary and sufficient conditions for kinetically generated depth perception. An alternative is to view such perception as the preferred solution to the problem posed by the transforming stimulus as to what even in the world is producing that transformation. In several experiments it is shown that when other solutions are supportable by the stimulus, those same transformations will no longer lead to depth perception. These other solutions become preferred on the basis of rejection of certain coincidental features of the stimulus that otherwise would have to be accepted were the kinetic depth solution to be maintained. The findings are interpreted as challenging any theory that perception is simply the direct result of stimulation or of extraction of stimulus information and as supporting the Helmkoltzian rule of perception as a construction of the most reasonable representation. 相似文献
234.
Isaac I. Bejar 《Intelligence》1981,5(1):49-68
Recent literature has suggested there is a causal link between malnutrition and impaired cognitive development. From a selective review of this literature it is concluded that owing to methodological imperfections in many of these studies the presence or absence of such a link cannot be established, even if randomized experiments were to be carried out. It is argued that compensatory experiments, even though they are not as logically compelling as experiments where proper nutrition is withheld, are ethically justifiable and more useful strategically since they may suggest ways of improving the cognitive development of currently affected children, especially if a variety of compensatory treatments is implemented. A reanalysis of such an experiment was conducted to determine whether the nutritional or educational component of the treatment was responsible for the observed gains in cognitive development. The reanalysis indicated that after four years of treatment there was no association between cognitive and nutritional status. The results were discussed in relation to previous research. Some of the social implications of the results were also discussed. 相似文献
235.
236.
James E. Patton Donald K. Routh Stuart I. Offenbach 《Journal of abnormal child psychology》1981,9(3):355-370
Three experiments examined the influence of videotaped classroom events on the academic performance and study behavior of reading-disabled and normally reading children in grades 1 through 6. In experiments 1 and 2a an experimenter-controlled presentation of these distractors resulted in performance decrements, the magnitude of which was greater for higher difficulty tasks. The distractor effects were similar for the two groups in this condition. However, when the children themselves were allowed to control their degree of exposure to the same distractors in experiment 2b, the reading-disabled children were less likely to act to escape the distraction. Results are discussed in terms of children's metacognitive awareness of distraction, and implications for the classroom are considered. 相似文献
237.
238.
Without assuming any constraints on behavior, we derive the policy that maximizes overall reward rate on two variable-interval paradigms. The first paradigm is concurrent variable time-variable time with changeover delay. It is shown that for nearly all parameter values, a switch to the schedule with the longer interval should be followed immediately by a switch back to the schedule with the shorter interval. The matching law does not hold at the optimum and does not uniquely specify the obtained reward rate. The second paradigm is discrete trial concurrent variable interval-variable interval. For given schedule parameters, the optimal policy involves a cycle of a fixed number of choices of the schedule with the shorter interval followed by one choice of the schedule with the longer interval. Molecular maximization sometimes results in optimal behavior. 相似文献
239.
E. Allan Lind Robin I. Lissak Donald E. Conlon 《Journal of applied social psychology》1983,13(4):338-350
Process control, the capacity to influence the content of a conflict resolution hearing, has been found repeatedly to affect disputants' judgments of the fairness of conflict resolution procedures, but never has there been an unambiguous test of the effect in nonbinding procedures. It was hypothesized that disputants experiencing nonbinding conflict resolution procedures, as well as those experiencing binding conflict resolution, would judge as more fair procedures high in disputant process control. One hundred nineteen undergraduate males and females were placed in apparent conflict with other suhjects. The procedure used to resolve the conflict was either high or low in disputant process control and was either binding or nonbinding. The outcome of the conflict resolution procedure was either favorable or unfavordblc to the subject. High disputant process control procedures were judged more fair than low disputant process control procedures regardless of whether the decision was binding, confirming the hypothesis. The results support new applications of procedural fairness theory and research and encourage testing of process control-like variables in nonlegal settings. 相似文献
240.