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A First Course in Database Systems by J. Ullmann, et. al.,

By J. Ullmann, et. al.,

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Strict partial ordering relations are transitive, irreflexive, and antisymmetrical. We can express these semantic properties directly in PENG Light via two conditional statements: 14. If X is a subclass of Y and Y is a subclass of Z then X is a subclass of Z. 15. If X is a subclass of Y then X is not equal to Y. 3 Part-Whole Relations A part-whole relation (or meronymic relation) has similar semantic properties as the class inclusion relation: it is a transitive, hierarchical, inclusion relation and can provide structure to the terminology.

2 Subclass Relations A subclass relation (or class inclusion) is often expressed in unrestricted natural language in the form: An A is a B or An A is a kind of B whereas A is referred to as the specific entity type and B the generic entity type. In linguistics, A is called a hyponym and B a hypernym. A hyponym is a word whose semantic range is included within that of another word, its hypernym. In PENG Light, we distinguish between subclass relations such as in (11) and (12), and class membership such as in (13): 11.

Having set up the incompatibility between these two means of engendering respect, we negate one of them, hence implying the other. To this extent we establish positive regard for the nucleus by means of indicating negative regard for the satellite. However, we cannot expect that every instance of Antithesis will include a satellite stated with explicit negative quality: 2) I'd rather lose an election than see my country lose a war. —John McCain While it might seem unlikely that any politician would under any circumstances prefer to lose an election, it is this expectation that gives the statement its rhetorical punch.

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