Evaluation of the Mechanical Properties of Electroslag Refined Fe-12Ni Alloys

Three Fe-12Ni alloys, individually alloyed with small amounts of V, Ti, and Al, were manufactured through different melting techniques, with special emphasis on electroslag remelting, in order to achieve different levels of metal purity and associated costs. The relative effectiveness of these melting techniques was evaluated from tensile and slow bend fracture toughness behavior at 25 C and -196 C after tempering the test specimens at various temperatures. The best melting procedure was vacuum induction melting (VIM) with or without electroslag remelting (ESR). VIM+ESR is the recommended procedure since ESR provides increased yield of plate product, a reduction of overall manufacturing costs and, depending on the alloy composition, improved tensile and fracture toughness properties

Experimental on-stream elimination of resonant whirl in a large centrifugal compressor

Resonant whirl condition during operation of a multi-stage centrifugal compressor at higher than anticipated speeds and loads was reported. The condition was diagnosed by a large scale computerized Machinery Condition Monitoring System (MACMOS). This computerized system verified that the predominant subsynchronous whirl frequency locked in on the first resonant frequency of the compressor rotor and did not vary with compressor speed. Compressor stability calculations showed the rotor system had excessive hearing stiffness and inadequate effective damping. An optimum bearing design which was developed to minimize the unbalance response and to maximize the stability threshold is presented

Acoustic transducer apparatus with reduced thermal conduction

A horn is described for transmitting sound from a transducer to a heated chamber containing an object which is levitated by acoustic energy while it is heated to a molten state, which minimizes heat transfer to thereby minimize heating of the transducer, minimize temperature variation in the chamber, and minimize loss of heat from the chamber. The forward portion of the horn, which is the portion closest to the chamber, has holes that reduce its cross-sectional area to minimize the conduction of heat along the length of the horn, with the entire front portion of the horn being rigid and having an even front face to efficiently transfer high frequency acoustic energy to fluid in the chamber. In one arrangement, the horn has numerous rows of holes extending perpendicular to the length of horn, with alternate rows extending perpendicular to one another to form a sinuous path for the conduction of heat along the length of the horn

Design and Implementation of Visual Cryptography System for Transmission of Secure Data

In recent period of time security of the transmitted data is most critical problem, as network technology is greatly advanced and heaps of information is transmitted via net. Visual cryptography strategy is one of the most secure technique for privacy auspices, that allow the encryption of secret image or data by transferring it into the secure percentage and such a strategy is able to recover the secret image or data. This behavior makes visual cryptography especially useful for the low computation load requirement. In this paper, we are providing the information regarding information security by using Visual Cryptography scheme by making use of exclusive new technique of splitting of images along with their pixels rotation with the help of generated random number. We also have made an attempt to overcome some of the disadvantages of preexisting techniques of encryption and decryption. Finally, successful transmission of the message from transmitting end to receiving end without any interception was done. Most importantly, it is very difficult to hack by use of any professional hacking techniques as the message is encrypted twice. Hence the data is highly secured under transmission pat

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