We introduce a probabilistic extension of propositional intuitionistic logic. The logic allows making statements such as P≥sα, with the intended meaning “the probability of truthfulness of α is at least s”. We describe the corresponding class of models, which are Kripke models with a naturally arising notion of probability, and give a sound and complete infinitary axiomatic system. We prove that the logic is decidable. 相似文献
Operation logic is a formal logic with well-defined formulas as semantic language clauses and with modus ponens rules as a method of reasoning. Operation logic can be implemented on any database management system (as the so-called OLS) having a universal general knowledge database and enabling understanding of data stored in the database. Semantic language clauses have necessary and sufficient properties for being able to describe any process in the world. Semantic language is the deepest level of any natural language, the level of data storing, understanding and reasoning. OLS can be a tool for studying implementation possibilities of human-like consciousness, for building artificial experts and artificial encyclopedias and for constructing semantic mathematical theories of anthropoecosystems (which is such an exact theory that qualitative information can be used with meaning completely defined by the user). In the paper the theory (and complete information enabling implementation) is presented for human-like understanding, topic-focus division of clauses, for human-like problem solving (program synthesis and verification) and for semantic mathematical analyses. Many examples are presented. 相似文献
Environmental risk assessment is an essential element in any decision-making process in order to minimize the effects of human activities on the environment. Unfortunately, often environmental data tends to be vague and imprecise, so uncertainty is associated with any study related with these kind of data.
Essentially, uncertainty in risk assessment may have two origins – randomness and incompleteness. There are two main ways to deal with these uncertainties – probability theory and fuzzy logic.
Probability theory is based on a stochastic approach, using probability functions to describe random variability in environmental parameters.
Fuzzy logic uses membership functions and linguistic parameters to express vagueness in environmental issues.
We discuss the best way to deal with uncertainties in the environmental field and give examples of probabilistic and fuzzy-logic approaches applied to environmental risk assessment. 相似文献
A novel fluorophore 1,3-bis(1,1,3-trimethyl-1H-benzo[e]indol-2(3H)-ylidene)propan-2-one (L) was synthesized and fully characterized by 1H NMR, 13C NMR, HRMS, and X-ray single-crystal structural analysis. Compound L is a pH-controlled molecular switch due to its protonation. The fluorescence change in protic polar solvents means that this compound also could be used as a protic solvent polarity sensor. Among the considered metal ions, the fluorescence of compound L could be quenched completely by Hg2+ ions with a high selectivity. Based on these fluorescence characters, this fluorescent dye L has promising applications as a multiple-mode molecular logic system. 相似文献