Gearboxes and similar machines containing rotating parts are complex systems with complicated structure and couplings. Generally they can be decomposed into more simple subsystems. These subsystems are usually rotating shafts with gears joined
by gear couplings and housing coupled with rotating shafts by bearings. The paper is aimed at the mathematical modelling of gearboxes with spur helical gears considered including their interior rotating shaft system and housing. The used bearing model
respects real number of rolling elements and roller contact forces acting between the journals and the outer housing. The model of a complete gearbox is created using the modal synthesis method. The kinematic transmission errors in gear couplings are viewed as sources of excitation. Vibration and noise analysis of the gearbox housing is performed by means of the created model. Four types of objective functions suitable for optimization from the radiated noise point of view are proposed. The presented methodology is applied to the simple test-gearbox. and Obsahuje seznam literatury
The ‘buccal complex’ of Pricea multae Chauhan, 1945 consists of two buccal suckers, the pharynx, a putative taste organ and the mouth cavity. The two suckers are dorsal to the mouth cavity, and the pharynx posterior to them. The septum in each sucker consists of connective tissue containing muscle filaments, lined by tegument with short irregular microvilli. The mouth cavity and the lumen of the suckers are lined by tegument with short irregular lamellae and by tegument with long bulbous, interconnected lamellae, separated from each other and from the body surface tegument by septate junctions. A ventral extension of the mouth cavity is also lined by tegument with short irregular lamellae. An anterior ‘taste organ’ is lined by ‘normal’ (body) tegument and tegument with short irregular lamellae. Glandular ducts open into it, and it contains many small uni-ciliate and multiciliate receptors, as well as two receptor complexes each consisting of a large non-ciliate receptor surrounded by small and large uniciliate receptors, with multiciliate receptors closeby. The four types of receptors are described in detail. The anterior part of the pharyngeal lumen is lined by an epithelium with dense surface lamellae and is penetrated by non-ciliate receptors. Attention is drawn to significant differences between the buccal complexes of the polyopisthocotylean monogeneans Pricea multae (Gastrocotylidae), Gotocotyla secunda (Tripartii, 1956) (Gastrocotylidae), Pulylabroides australis (Murray, 1931) (Microcotylidae), Zeuxapia serialae (Meserve, 1938) (Axinidae) and Diclidophora merlangi (Kuhn, 1832) (Diclidophoridae).