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1.
2.
Czesław Lejewski 《Studia Logica》1989,48(4):479-494
The most difficult problem that Leniewski came across in constructing his system of the foundations of mathematics was the problem of defining definitions, as he used to put it. He solved it to his satisfaction only when he had completed the formalization of his protothetic and ontology. By formalization of a deductive system one ought to understand in this context the statement, as precise and unambiguous as possible, of the conditions an expression has to satisfy if it is added to the system as a new thesis. Now, some protothetical theses, and some ontological ones, included in the respective systems, happen to be definitions. In the present essay I employ Leniewski's method of terminological explanations for the purpose of formalizing ukasiewicz's system of implicational calculus of propositions, which system, without having recourse to quantification, I first extended some time ago into a functionally complete system. This I achieved by allowing for a rule of implicational definitions, which enabled me to define any propositionforming functor for any finite number of propositional arguments.To the memory of Jerzy Supecki 相似文献
3.
Adam Obtułowicz 《Studia Logica》1989,48(3):299-317
In the paper there are introduced and discussed the concepts of an indexed category with quantifications and a higher level indexed category to present an algebraic characterization of some version of Martin-Löf Type Theory. This characterization is given by specifying an additional equational structure of those indexed categories which are models of Martin-Löf Type Theory. One can consider the presented characterization as an essentially algebraic theory of categorical models of Martin-Löf Type Theory. The paper contains a construction of an indexed category with quantifications from terms and types of the language of Martin-Löf Type Theory given in the manner of Troelstra [11]. The paper contains also an inductive definition of a valuation of these terms and types in an indexed category with quantifications. 相似文献
4.
Gail F. Brenner Nancy K. Norvell Marian Limacher 《American journal of community psychology》1989,17(6):831-836
Assessed the number of sources of supportive and problematic social interactions in the total social network as well as the number who were the sources of consistently supportive or problematic interactions in a sample of 2nd year medical students. Number of problematic interaction sources was hypothesized to be more predictive of psychological and physical well-being than number of supportive interaction sources. Results showed that total supportive and total problematic interaction sources were equally predictive of life satisfaction. The presence of at least one individual who is a consistent source of problematic interactions was most predictive of lower life satisfaction. Results indicate the importance of studying both supportive and problematic social interactions. They also suggest that interactions with individuals that are consistently problematic may negatively impact upon well-being. 相似文献
5.
Jarosław Achinger 《Studia Logica》1986,45(3):293-300
Universality of generalized Alexandroff's cube
plays essential role in theory of absolute retracts for the category of , -closure spaces. Alexandroff's cube.
is an , -closure space generated by the family of all complete filters. in a lattice of all subsets of a set of power
.Condition P(, ,
) says that
is a closure space of all , -filters in the lattice (
),
.Assuming that P (, ,
) holds, in the paper [2], there are given sufficient conditions saying when an , -closure space is an absolute retract for the category of , -closure spaces (see Theorems 2.1 and 3.4 in [2]).It seems that, under assumption that P (, ,
) holds, it will be possible to givean uniform characterization of absolute retracts for the category of , -closure-spaces.Except Lemma 3.1 from [1], there is no information when the condition P (, ,
) holds or when it does not hold.The main result of this paper says, that there are examples of cardinal numbers, , ,
such that P (, ,
) is not satisfied.Namely it is proved, using elementary properties of Lebesgue measure on the real line, that the condition P (,
1, 2
) is not satisfied.Moreover it is shown that fulfillment of the condition is essential assumption in, Theorems 2.1 and 3.4 from [1] i.e. it cannot be eliminated. 相似文献
6.
The main theorem says that a consequence operator is an effective part of the consequence operator for the classical prepositional calculus iff it is a consequence operator for a logic satisfying the compactness theorem, and in which every finitely axiomatizable theory is decidable. 相似文献
7.
Generalization of auditory intensity as a function of small amounts of discrimination training 下载免费PDF全文
Rosemary Pierrel J. Gilmour Sherman Marian W. Fischman 《Journal of the experimental analysis of behavior》1963,6(4):545-548
Rats were trained on a two-valued auditory-intensity discrimination for 5, 2, 1 or 0 days. Then, the bar-press response rate was sampled in the presence of seven added discrimination stimuli (generalization) for seven days. Daily training sessions were 4 hr in length throughout the experiment. Only the five-day group exhibited a marked superiority on the multi-valued discrimination when contrasted with the group having had no prior simple discrimination training. 相似文献
8.
9.
10.
Dr. Marian Radke-Yarrow Editha Nottelmann Barbara Belmont Jean Darby Welsh 《Journal of abnormal child psychology》1993,21(6):683-695
The expressed affect of clinically depressed and nondepressed mothers as measured by the Schedule for Affective Disorders and Schizophrenia: Lifetime Version (SADSL) and their children (1 1/2 to 3 1/2 years) was observed in seminatural situations. The objectives were to investigate how maternal depression enters into affective interactions between mother and child and how the affect patterns of mother and child are related. Fortynine unipolar and 24 bipolar depressed mothers and 45 nondepressed mothers were observed on 2 days, 2 weeks apart, for a total of 5 h. Each minute was coded for the predominant affect of mother and child. Affects relevant to depression (anxioussad, irritableangry, downcast, pleasant, tenderaffectionate) were coded. Depressed mothers expressed significantly more negative affect than did control mothers. Mothers' expressed affect and their selfreports of affect on days of observation were unrelated. Mother's and child's affects, measured on different days, were significantly correlated. Unipolar mothers and mothers severely depressed spent significantly more time in prolonged bouts of negative affect. There was significant synchrony between their bouts and the negative bouts of their daughters. Gender of child was related to mother's and child's affect, and to relations between mother's and child's affect. 相似文献