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[en] The 30 MHz high harmonic fast wave (HHFW) antenna array for NSTX consists of 12 current straps, evenly spaced in the toroidal direction. Each pair of straps is connected as a half-wave resonant loop and will be driven by one transmitter, allowing rapid phase shift between transmitters. A decoupling network using shunt stub tuners has been designed to compensate for the mutual inductive coupling between adjacent current straps, effectively isolating the six transmitters from one another. One half of the array, consisting of six full-scale current strap modules, three shunt stub decouplers, and powered by three phase-adjustable rf amplifiers had been built for electrical testing at ORNL. Low power testing includes electrical characterization of the straps, operation and performance of the decoupler system, and mapping of the rf fields in three dimensions
[en] In the decommissioning and decontamination(D and D) planning stage, it is important that the scenarios are evaluated from an engineering point of views because the decommissioning work has to be executed economically and safely by following the best scenarios. Therefore, we need to develop several modules to evaluate the decommissioning scenarios. In this paper, the digital mock-up system is constructed in the virtual space to simulate the whole decommissioning process. The schedule evaluating equation and cost evaluation equation are derived to calculate the working time and the expected cost. And in order to easily identify the radiation level about the activated objects, the radiation visualization module is developed. Finally, on the basis of the obtained results from the Digital Mock-up and other important factors, the evaluating method of the scenarios that can indicate the best scenario is described.
[en] The performances of a tele-operation system are related to the master arm's ability to emulate the behavior of the remote environment. Ideally, it allows the operator to control the slave arm in a natural way as if that were an extension of its own body. The criteria to be checked for that are known but contradictory. It is thus necessary to make trade-offs on which there is not consensus. Existing input devices are therefore very varied thus more or less adapted to the tasks considered, which is in general checked a posteriori. In this document, we propose an original approach allowing to dimension the master arm a priori according to the use which one wishes to make. For that, we developed two tools: - the first one makes it possible to establish his specifications by taking account of the transmission of information between the operator and the slave arm. By exploiting their respective limitations, one is assured that the master arm will not limit the performances of the system, - the second one allows to design it (kinematics, size, motorization... ) according to the preceding specifications. For that, we use well-known theoretical tools which however are approached here as design tools. This leads to the definition of new concepts which do not appear in the literature. This approach is used to establish the specifications of a master arm for nuclear and offshore tele-operation then to design two input devices answering these specifications. The first has 3 degrees of freedom with force feedback. Its performances are higher than those of the best existing input devices. The second is a mock-up of a 6 degrees of freedom master arm. It uses a new parallel structure that is redundant in actuation and whose performances are remarkable. (author)
[fr]Les performances d'un systeme de teleoperation sont liees a la capacite du bras maitre a emuler le comportement de l'environnement distant. Dans un cas ideal, cela permet a l'operateur de commander le robot esclave de facon naturelle comme si celui-ci etait une extension de son propre corps. Les criteres a verifier pour cela sont connus mais contradictoires. Il est donc necessaire de faire des compromis sur lesquels il n'existe pas de consensus. Il en resulte que les organes de commande existants sont tres varies donc plus ou moins adaptes aux taches envisagees, ce qui est en general verifie a posteriori. Dans ce memoire, nous proposons une approche originale permettant de dimensionner le bras maitre a priori en fonction de l'utilisation que l'on souhaite en faire. Pour cela, nous avons developpe deux outils: - Le premier permet d'etablir un cahier des charges en tenant compte de la transmission des informations entre l'operateur et le bras esclave. En exploitant leurs limitations respectives, on est assure que le bras maitre ne limitera pas les performances du systeme, - Le second permet de le dimensionner (geometrie, taille, motorisation,... ) pour qu'il reponde aux specifications precedentes. Pour cela, nous utilisons un certain nombre d'outils theoriques classiques qui sont toutefois abordes ici en tant qu'outils de conception, ce qui conduit a la definition de nouveaux concepts qui n'apparaissent pas dans la litterature. Cette approche est utilisee pour etablir le cahier des charges d'un bras maitre pour la teleoperation nucleaire et off-shore puis pour concevoir deux organes de commande repondant a ces specifications. Le premier est un bras a 3 degres de liberte a retour d'effort. Ses performances sont superieures a celles des meilleurs organes de commande existants. Le second est une maquette de bras a 6 degres de liberte a retour d'effort. Il utilise une nouvelle structure parallele et redondante en actionnement dont les performances sont remarquables
[en] This study introduces a remote simulator to verify and validate an operability and maintenance ability of a remote manipulator in a pyroprocess facility at a design stage. To evaluate an operability and maintenance ability of the devices, it needs various modules. This article describes a system architecture which illustrates an interface between its modules. In nuclear industry, an advanced modeling and simulation technology which can simulate various phenomena by using a digital mockup has been increased. Even several research and development in order to improve the efficiency of a remote operation in the ACPF digital mock-up were carried out, these research results have a lot of limitations in order to apply it to real world. Especially simulations that depend on 3D graphics are limited to the analysis of an accessibility and operability of a manipulator. To solve these limitations, this article proposes a scheme to enable an operator to improve a remote manipulation by using a haptic device which is a force feed-back device
[en] A model block used for the model experiment is produced using input parameters. The effects which regularly take place in the locality in question (zone approach, raise deformation, overburden collapse) are visually observed on the model. If the expected effect does not take place, it can be induced either on the same or another model. Modelling of massif properties and of a known effect is useful for reliable forecasting in mining. (H.S.)
[en] After several PWSCCs were found in Bugey(France), Ringhals(Sweden), Tihange(Belgium), Oconee, Arkansas, Crystal Fever, Davis-Basse, VC Summer(U.S.A.), Thuruga(Japan), USNRC and PNNL started the research on PWSCC, that is, PINC project. The aim of this project is to fabricate and obtain representative NDE mock-ups with flaws to simulate tight PWSCC cracks, to identify and quantitatively assess NDE methods for accurately detecting, sizing and characterizing tight cracks such as PWSCC, to document the range of locations and crack morphologies associated with PWSCC and observed responses and to incorporate findings from other ongoing PWSCC research programs, as appropriate. By participating in PINC project, Korean morphology technique about PWSCC and NDE technique have improved and become similar lever with other advanced country. Therefore, the evaluation technique of integrity for nickel alloy component has been improved by cooperation with university, research institute and industries.