ASPECTE TEORETICO-PRACTICE ÎN STOMATOLOGIA MODERNĂ

COMUNICĂRI ÎN PLEN 1. Chele Nicolae. Reabilitarea implanto-protetică în atrofii severe ale maxilarelor 2. Solomon Oleg. Particularitățile de diagnostic și tratament în edentațiile congenitale 3. Mostovei Andrei. Reabilitarea implanto-protetică a pacienților cu chisturi radiculare 4. Trifan Valentina. Actualități în asistența ortodontică din Republica Moldova prin prisma ortodonției mondial

THEORETICAL CONTRIBUTIONS ON THE SELECTION OF POSSIBLE TRIBOLOGICAL COUPLES OF MATERIALS FOR THE MANUFACTURE OF PRECESSIONAL TRANSMISSIONS

Selecting gear materials is a great challenge for engineers. Gear teeth are subject to difficult and severe loading conditions. Simultaneous action of alternating normal and tangential dynamic stresses occurs, contact deformations accompanied by sliding friction. Gears are subject to increased requirements in terms of strength, geometric accuracy, dimensional stability, and durability. For the manufacture of gears, especially from thermoplastic materials, a theoretical argumentation of the materials is needed. An extensive study of thermoplastic materials, around the world needs to be done and the most efficient tribological couples to be chosen in terms of heat transfer from the gear zone, operation with or without lubrication, and gear life. In this paper, a theoretical synthesis of the Steel / Plastic, Plastic / Plastic, Plastic/Steel tribological couples is made, which were used in conformist and non-conformist experiments. Therefore, selected tribological couples are supposed to be used in the Precessional Transmissions applications

Decision Rules and their Influence on Asset Prices

This paper develops a market microstructure model with asymmetric information in order to quantify the influence which practical decision rules have on asset process. The users of practical decision rules have incomplete information at their disposal and trade in a market with both fully informed and uninformed investors, as well as with a competitive market maker. The users of practical decision rules affect the periodical ask and bid prices in two ways: by means of the precision of their information and through their share in the totality of investors, respectively. The resulting bid-ask spread is positive and proportional to the c.p. variation of these two influencing factors and is attributable to the adverse selection costs