1,037 research outputs found

    Operating characteristics of a cantilever-mounted resilient-pad gas-lubricated thrust bearing

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    A resilient-pad gas thrust bearing consisting of pads mounted on cantilever beams was tested to determine its operating characteristic. The bearing was run at a thrust load of 74 newtons to a speed of 17000 rpm. The pad film thickness and bearing friction torque were measured and compared with theory. The measured film thickness was less than that predicted by theory. The bearing friction torque was greater than that predicted by theory

    Experimental evaluation of foil-supported resilient-pad gas-lubricated thrust bearing

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    A new type of resilient-pad gas thrust bearing was tested to determine the feasibility of the design. The bearing consists of carbon graphite pads mounted asymmetrically on foil beams. Two bearing configurations were tested at thrust loads from 27 to 80 newtons at speeds to 9000 rpm. The outside diameter of the bearing was 8.9 centimeters

    Evaluation of chromium oxide and molybdenum disulfide coatings in self-acting stops of an air-lubricated Rayleigh step thrust bearing

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    Two coatings for a Rayleigh step thrust bearing were tested when coasting down and stopping under self-acting operation in air. The thrust bearing had an outside diameter of 8.9 cm (3.5 in.), an inside diameter of 5.4 cm (2.1 in.), and nine sectors. The load was 73 N (16.4 lbf). The load pressure was 19.1 kN/per square meter (2.77 lbf/per square inch) on the total thrust bearing area. The chromium oxide coating was good to 150 stops without bearing deterioration, and the molybdenum disulfide coating was good for only four stops before bearing deterioration. The molybdenum disulfide coated bearing failed after nine stops

    Operation of hydrodynamic journal bearings in sodium at temperatures to 800 deg F and speeds to 12000 rpm

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    Operation of hydrodynamic journal bearings in liquid sodium at high temperatures and high speed

    Cloud Workload Prediction by Means of Simulations

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    Clouds hide the complexity of maintaining a physical infrastructure with a disadvantage: they also hide their internal workings. Should users need to know about these details e.g., to increase the reliability or performance of their applications, they would need to detect slight behavioural changes in the underlying system. Existing solutions for such purposes offer limited capabilities. This paper proposes a technique for predicting background workload by means of simulations that are providing knowledge of the underlying clouds to support activities like cloud orchestration or workflow enactment. We propose these predictions to select more suitable execution environments for scientific workflows. We validate the proposed prediction approach with a biochemical application

    Nyelvi udvariasság/udvariatlanság és metapragmatika (Linguistic politeness, impoliteness and metapragmatics

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    Az udvariasság2 olyan jelenség, amelyről mindannyian szoktunk reflektíven beszélni és gondolkodni. E reflekciós jelenség számos formában megnyilvánulhat: reflekciónak számít például, ha különböző nyelvi interakciókról vagy azok résztvevőiről beszélünk (például: „láttad, milyen bunkó volt?”), de reflektívek a megfelelőnek tartott társadalmi viselkedéssel foglalkozó illemtankönyvek is. Az udvariasság és a hozzá kapcsolódó kérdések tárgyalásának relevanciája és történelmi beágyazottsága ugyanakkor kultúránként változó: némely kultúrában ennek évezredes hagyományai vannak, máshol ez kevésbé jellemző. The udvariasság2 a phenomenon which is all we used to talk about reflective and to think. This reflection phenomenon can manifest in many forms: a reflection of matter, for example, when different linguistic interactions or participants of we are talking about (for example: "Did you see what kind of jerk?"), but reflective of the appropriate It held social behavior on etiquette books. courtesy and the related issues of negotiations and historical relevance However, culturally imbedded variable: some of this millennial culture There are traditions, in others it is less commo

    Towards efficient virtual appliance delivery with minimal manageable virtual appliances

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    Infrastructure as a Service systems use virtual appliances to initiate virtual machines. As virtual appliances encapsulate applications and services with their support environment, their delivery is the most expensive task of the virtual machine creation. Virtual appliance delivery is a well-discussed topic in the field of cloud computing. However, for high efficiency, current techniques require the modification of the underlying IaaS systems. To target the wider adoptability of these delivery solutions, this article proposes the concept of minimal manageable virtual appliances (MMVA) that are capable of updating and configuring their virtual machines without the need to modify IaaS systems. To create MMVAs, we propose to reduce manageable virtual appliances until they become MMVAs. This research also reveals a methodology for appliance developers to incorporate MMVAs in their own appliances to enable their efficient delivery and wider adoptability. Finally, the article evaluates the positive effects of MMVAs on an already existing delivery solution: the Automated Virtual appliance creation Service (AVS). Through experimental evaluation, we present that the application of MMVAs not only increases the adoptability of a delivery solution but it also significantly improves its performance in highly dynamic systems. © 2013 IEEE
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