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Exploiting collective knowledge with three-way decision theory: Cases from the questionnaire-based research
No full textTwo methods are proposed for collective knowledge extraction from questionnaires with ordinal scales and dichotomous questions. Both methods are based on a three-way decision procedure and a statistical method aimed at attaining statistical significance of the above decision. One method is aimed at giving an (absolute) assessment of “objects” according to a given “criterion” and the other one at producing a relative ranking of the “objects”. A criterion can be related to one or more questionnaire items (usually questions or statements). In this latter case a method to compose ordinal items in aggregate scores is also given. The paper also presents two various case studies that illustrate the methods and give motivations for their application in different domains where the knowledge of a community or any distributed group of experts can be externalized (in terms of users' perceptions, attitudes, opinions, choices) with a structured closed-ended questionnaire
Sintesi stereoselettiva di (Z)-3-alchilidenftalidi e di isocumarine 3-sostituite naturali e non naturali a partire da 2-idrossiarilcarbossilati alchilici
No full textModeling the Dynamics of Multiple Disease Occurrence by Latent States
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197696.pdf (Publisher’s version ) (Open Access)Scalable Uncertainty Management: 12th International Conference, SUM 2018, Milan, Italy, October 3-5, 201
Algebraic structures related to many valued logical systems - part II: Equivalence among some widespread structures
No full textSynthesis of vinyl nonaflates derived from beta-ketoesters, beta-diketones and alpha-diketones and their palladium-catalyzed cross-coupling reactions with organozinc halides
No full textCyclic and acyclic beta-ketoesters 4, a typical cyclic alpha-diketone 5 and a typical cyclic beta-diketone 6 were convened to the corresponding vinyl nonaflates of general formula 7, 8 and 9, respectively, by reaction with 1.2-1.5 equiv of NaH in DMF at 20-55 degrees C followed by treatment with 1.15-1.30 equiv of perfluoro-1-butanesulfonyl fluoride at 20 degrees C. These vinyl nonaflates, which were purified by MPLC on silica gel, proved to be excellent electrophiles in Pd-catalyzed cross-coupling reactions with aryl-, 1-alkynyl- and alkylzinc chlorides. A variety of cyclic and acyclic tetrasubstituted alpha,beta-unsaturated esters which included stereoisomerically pure compounds, a 2-substituted 3-aryl-2-cyclopentenone and naturally-occurring dihydrojasmone were cleanly synthesized by these smooth and selective cross-coupling reactions. (C) 1999 Elsevier Science Ltd. All rights reserved
Palladium-catalyzed one-pot synthesis of stereodefined 3-[(1,1-unsymmetrically disubstituted)methylidene]isobenzofuran=1(3H)-ones and stereodefined 5-[(1,1-unsymmetrically disubstituted)methylidene]furan-2(5H)-ones
No full textReazioni di cross-coupling mediate da palladio tra reagenti organozinco e vinil nonaflati derivanti da beta-chetoesteri, beta-dichetoni ed alfa-dichetoni
No full textA new synthesis of fungicidal methyl (E)-beta-methoxypropenoates
No full textSeveral structural analogues of strobilurin A having general formula (E)-18, in which the methyl (E)-3-methoxypropenoate unit is linked to substituted aromatic, alkenyl or cyclopentenyl substrates, have been efficiently and selectively prepared by Pd-catalyzed cross-coupling reactions between (Z)-2-methoxy-1-(methoxycarbonyl)ethenylzinc halides, (Z)-19, and aryl halides, alkenyl halides or triflates or cyclopentenyl triflates, respectively. Compounds (Z)-19, which represent a new class of highly functionalized and stereodefined organozinc derivatives, have been synthesized in very high yield by reaction of THF solutions of easily available methyl (Z)-2-iodo- or (Z)-2-bromo-3-methoxypropenoate, (Z)-8 and (Z)-12, respectively, with an activated Zn/Ag couple in the presence of TMEDA. Compounds (E)-18 synthesized according to this procedure include substances which are known to be able to control agrochemically important fungi as well as derivatives which are able to inhibit the growth of fungi which deteriorate papery materials. (C) 1998 Elsevier Science Ltd. All rights reserved
Algebraic structures related to many valued logical systems - part I: Heyting Wajsberg algebras
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