Investigation of Stress-Strain State of Ball Mill Trunnion

The article discusses the trunnion of a ball mill in the framework of the theory of elasticity, which is subjected to uneven thermal effects due to the heating load. Long-term operation of the mills leads to a significant wear of mainly mechanical parts of the supporting rotating parts-pins. There are various defects on the working surface of the trunnion, which, under the action of dynamic loads, contributes to the loss of working capacity and long downtime during repair. The study of the stress-strain state will determine the parameters for restoring the cylindrical surface of the trunnion. The equations describing the radial displacement of a point inside the trunnion of a ball mill are obtaine

RESULTS OF NUMERICAL RESEARCH OF DISCHARGE CAPACITY OF A SPILLWAY WITH A WIDE THRESHOLD

The problem of dramatically changing river flow in the reaches of hydro-technical structures is considered in the paper. The discharge capacity of these structures is determined by the well-known formula of a spillway with a wide threshold based on the Saint-Venant system of equations. It was stated that the Froude number in an undisturbed flow increases at the narrowing of the channel and decreases with its widening, and in a turbulent flow the Froude number decreases with the narrowing of the channel, and increases with its widening. Proceeding from this, the transition of a flow from a calm regime to a turbulent one can occur only when the form of the channel transfers from a narrow form to a wide one; in the narrowest section of the channel flow, the Froude number and the kinetic parameter is Fr=Pk=1,0. The characteristic features of the flow coefficient of a spillway with a wide threshold are identified and a recommendation is given for its determination. The main factor that affects the discharge capacity of a spillway with a wide threshold is analyzed. It is determined by the product of the values of the hydraulic resistance and compression coefficients in the inlet of the structure

Coordination: Reo, nets, and logic

This article considers the coordination language Reo, a Petri net variant called zero-safe nets, and intuitionistic temporal linear logic (ITLL). The first part examines the semantics of the coordination language Reo in relation to zero-safe nets. Although the external presentations of the two models are quite different, the difference in underlying semantics is rather small. In fact, Reo connectors can be compositionally encoded into zero-safe nets. This means that the tools and techniques developed for Petri nets over the last 30 years, such as various extensions to the zero-safe nets model, such reconfigurable and dynamic nets, can be adapted to the Reo setting. The second part re-examines the idea of using linear logic as a basis for coordination languages. Specifically, we argue that intuitionistic temporal linear logic (ITLL) can encode the semantics of Reo and zero-safe nets, by encoding their notion of transaction. Moreover, by adapting the encoding and exploring the additional connectives of ITLL, it can form the basis of an expressive coordination language which goes beyond these models, by introducing means for explicitly reasoning about choices made by the environment and by providing more fine-grained control over the timing of interaction.status: publishe