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The purpose of this paper is to measure and analysis the vibrations of electric motors on board container ships, in order to reduce the maintenance costs and implicitly in making the optimal decisions. In general, the faults that underlie electric motors are primarily due to mechanical and electrical efforts. Mechanical stresses occur as a result the overloads and rapid load variations. On the other hand, the overcurrents and overvoltages are usually in the close accordance with the power supplies. In this regard the mechanical faults cannot be analyzed by changing the parameters like voltage, current, power, frequency but in practice we can do analysis by used the high-performance testers with intelligent software for measuring the motor vibrations. The MarVib DC650 tester was used in this paper for analysis and measurement the vibrations of electric motors. [ABSTRACT FROM AUTHOR]

Power transformers are the basic components of a naval power system at the same time as the equipment with the most significant losses. The deforming regime is introduced by the power electronics in the case of ships of static frequency converters, cycloconverters or syncroconverters (variable speed drives) for the control of propulsion motors, etc. The central theme of this paper is the impact of the deforming regime on power and energy losses in the case of electrical transformers on board cruise ships. For this purpose, the analytical model regarding the determination of losses in transformers when operating in deforming regime is presented. In addition to the winding losses, the magnetic and dielectric circuit also includes additional losses due to the deforming regime. At the same time, an analysis was performed regarding the optimal operation management of the power transformers affected by the deforming regime. [ABSTRACT FROM AUTHOR]

We have studied the interaction of hydrogen with small neutral and anionic carbon clusters using density functional calculations. The geometry, stability, and electronic structure of these clusters show an odd–even alternation originating in the bonding nature of the carbon atoms. Our mass spectrometric measurements of the abundance of C[sub n]H[sup -] (n≤10) cluster anions produced by gas-feed Cs sputtering from different crystallographic forms of carbon display similar odd–even alternation with the even-n clusters being relatively more abundant. The calculated trend in the adiabatic electron affinities shows a behavior similar to the experimental abundance pattern. We discuss a possible partial suppression of the chain-to-ring transformation (which normally occurs at n=10 in C[sub n][sup -]) in C[sub n]H[sup -] and compare it with our density functional calculations as well as observations in C[sub n]N[sup -]. We also observe that the size dependence of the abundance of C[sub n]H[sup -] clusters sputter ejected from a fullerene target exhibits a distinctly different power-law decline compared to crystalline and amorphous carbon. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

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Introduction: Pyoderma gangrenosum is the ulcerative form of neutrophilic dermatoses. The most frequent extracutaneous localizations are the lungs, joints, and digestive tract., Case Record: We report a case of Pyoderma gangrenosum, which presented first as an aseptic lung abscess. The first cutaneous lesions occurred 9 months later, with skin ulcerations on the thorax and on surgical scars. The histological diagnosis was made on skin biopsies. There was no associated abnormality except for IgA monoclonal gammapathy. Clinical improvement was noted with immunosuppressive treatment., Discussion: This infrequent case report underlines that lung abscesses may be of non-infectious origin, that in Pyoderma gangrenosum, skin lesions may be come several months after extracutaneous manifestations, among which lungs abcesses are the most frequent.