surge and rotating stall phenomena are two dynamic instabilities that occur in both axial and centrifugal compressors. surge is the stream instability phenomenon in compressor that imposes severe damages to the compressors. nowadays, suppressing surge phenomenon is one of the most important issues in oil and gas industries, especially when flow reduction or gas reflux is considered. this resear...

Background: Multiple sclerosis (MS) is a degenerative inflammatory disease which is most commonly diagnosed by magnetic resonance imaging (MRI). But, since the MRI device uses of a magnetic field, if there are metal objects in the patient's body, it can disrupt the health of the patient, the functioning of the MRI, and distortion in the images. Due to limitations of using MRI device, screening ...

This paper deals with bi-level control policy and queuing analysis of a machine repair problem. The model is developed by incorporating mixed standbys (cold and warm), reneging, set up and vacation time. The repair facility consists of two heterogeneous repairmen in the system. The life and repair time of the failed units and also their set up times are assumed to be exponentially distributed. ...

A finite switchboard state machine is a specialized finite state machine. It is built by binding the concepts of switching state machines and commutative state machines. The main purpose of this paper is to give a specific algorithm for fuzzy finite switchboard state machine and also, investigates the concepts of switching relation, covering, restricted cascade products and wreath products of f...

The purpose of this paper is to present a new type of dynamic balancing system, having a driving solution of the rotating part based on magnetic interactions. The magnetic system also plays the role of an elastic bearing. In the first part of the article is presented the technical solution which allows the dynamic balancing evaluation depending on the radial displacement between two disks with ...

In this paper we consider a production environment consisting of two machines and two products. Machine 1 is a dedicated server, which is capable of producing product 1 only. Machine 2 is a flexible server that can produce both product 1 and product 2. Both product 1 and product 2 are produced to stock. We characterize the form of the optimal policies that maximize the average profit per unit t...

An accurate average value model of synchronous machine-rectifier system considering the effect of stator resistance is derived in this paper. A proper voltage-behind-reactance synchronous machine model without any approximations is used for the generator that allows effective calculation of commutation displacement angle. All rectification modes of the rectifier are studied. A detailed switchin...

Logos analyzes whole source sentences, considering morphology, meaning, and grammatical structure and function. The analysis determines the semantic relationships between words as well as the syntactic structure of the sentence. Parsing is only source language-specific; generation is target language-specific. Although the Logos system was originally developed on the basis of a transfer approach...