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排序方式: 共有457条查询结果,搜索用时 390 毫秒
101.
Sophie Salasca Bruno Cantone André Grosman Basilio Esposito Fabio Moro Daniele Morocco Rosaria Villari Maurizio Angelone Esther Rincon Carlos Hidalgo Daniel Nagy Gabor Kocsis Paulo Varela Gabor Porempovics Guillaume Perrollaz Kunal Patel Yuri Krivchenkov Michael Walsh 《Fusion Engineering and Design》2013,88(6-8):602-606
Diagnostics in ITER are mandatory to characterize the parameters of plasma and study its interactions with plasma-facing components. Diagnostics components in the vicinity of the plasma are supported by metallic structures called port plugs. At the tokamak mid-plane, these components are installed in port plugs through intermediate structures called drawers. Apart from hosting the diagnostics, the port plugs act as shielding against neutrons and gammas, in order to limit the nuclear loads in crucial components (such as diagnostics and superconducting coils) as well as the dose levels in the controlled zones of the tokamak. The radiation shielding function of the port plugs is ensured through an optimized mixture of heavy metallic materials and water, forming shielding blocks surrounding the diagnostics and called Diagnostic Shield Modules (DSMs). These DSMs constitute the rear part of the drawers (the front part being composed of the Diagnostic First Wall). This paper presents the main results of a study performed in Europe on the integration of a particular diagnostics port plug, the Equatorial Port Plug 1 (EPP1). The paper first provides the results of the EPP1 diagnostics integration analysis. In a second step it focuses on the design of the EPP1 DSMs and summarizes the major results of a thorough set of analyses aiming at studying the DSMs behaviour under different loads, suggesting recommendations to improve their current design. 相似文献
102.
Kim Jo; Heinemann Allen W.; Bode Rita K.; Sliwa James; King Rosemarie B. 《Canadian Metallurgical Quarterly》2000,45(4):365
Objectives: To explore (a) how spiritual well-being (WB), emotional WB, life satisfaction, and functional status change during and after rehabilitation; (b) the relationships among these variables over time; and (c) associations with demographic and clinical characteristics. Study Design: Longitudinal assessment across 3 time points. Participants and Setting: 155 adults admitted to a freestanding rehabilitation hospital. Main Outcome Measures: Spiritual Well-Being Scale, Life Satisfaction Questionnaire, Short-Form Health Survey, and the Functional Independence MeasureTM. Results: Emotional WB increased during rehabilitation, whereas life satisfaction and spiritual WB did not change; however, substantial subgroups of individuals experienced changes in life satisfaction and spiritual WB over time. Measures of spiritual WB, emotional WB, and life satisfaction were moderately correlated within and across time points. Persons making smaller functional gains during inpatient rehabilitation were least likely to experience increased emotional WB. Although African Americans as a group reported greater spiritual WB than other racial-ethnic groups on admission, they were least likely to increase in emotional WB over time.… (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
104.
Zhenyong Zhang Jesper Steensgaard Gabor C. Temes Jian-yi Wu 《Analog Integrated Circuits and Signal Processing》2009,59(2):143-150
A dual-path 2-0 cascaded delta-sigma (MASH) ADC was implemented with fast digital correction of both DAC errors and MASH mismatch
errors. The digital correction techniques greatly reduced the requirements on the analog circuits. The dual-path structure
allows fast convergence and improved accuracy for the correction. Using a 20 MHz clock, the prototype chip achieved an 84 dB
dynamic range in a 1.25 MHz signal band, when fabricated in CMOS 0.18 μm process. 相似文献
105.
Previous research for detecting incipient wind turbine failures, using condition monitoring algorithms, concentrated on wind turbine Supervisory Control and Data Acquisition (SCADA) signals, such as power output, wind speed and bearing temperatures, using power‐curve and temperature relationships. However, very little research effort has been made on wind turbine SCADA alarms. When wind turbines are operating in significantly sized wind farms, these alarm triggers are overwhelming for operators or maintainers alike because of large number occurring in a 10 min SCADA period. This paper considers these alarms originating in two large populations of modern onshore wind turbines over a period of 1–2 years. First, an analysis is made on where the alarms originate. Second, a methodology for prioritizing the alarms is adopted from an oil and gas industry standard to show the seriousness of the alarm data volume. Third, two methods of alarm analysis, time‐sequence and probability‐based, are proposed and demonstrated on the data from one of the wind turbine populations, considering pitch and converter systems with known faults. The results of this work show that alarm data require relatively little storage yet provide rich condition monitoring information. Both the time‐sequence and probability‐based analysis methods have the potential to rationalize and reduce alarm data, providing valuable fault detection, diagnosis and prognosis from the conditions under which the alarms are generated. These methods should be developed and integrated into an intelligent alarm handling system for wind farms, aimed at improving wind turbine reliability to reduce downtime, increase availability and leading to a well‐organized maintenance schedule. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
106.
Iablokov V Beaumont SK Alayoglu S Pushkarev VV Specht C Gao J Alivisatos AP Kruse N Somorjai GA 《Nano letters》2012,12(6):3091-3096
Model cobalt catalysts for CO(2) hydrogenation were prepared using colloidal chemistry. The turnover frequency at 6 bar and at 200-300 °C increased with cobalt nanoparticle size from 3 to 10 nm. It was demonstrated that near monodisperse nanoparticles in the size range of 3-10 nm could be generated without using trioctylphosphine oxide, a capping ligand that we demonstrate results in phosphorus being present on the metal surface and poisoning catalyst activity in our application. 相似文献
107.
In this paper, we identify and describe the key ideas, concepts and software related to Medical Imaging that emerged from our research group, which is commonly known by the acronym MIPG, denoting Medical Image Processing Group. For the purpose of our presentation, we consider the entire discipline of Medical Imaging to consist of the areas of acquisition, postprocessing, evaluation, and application. We are indeed fortunate to be able to discuss seminal research from our group in each of these areas. In Section II, we identify relevant moments of inception and describe our past contributions. Our achievements, current activities, and future directions are summarized in Section III, Section IV, and Section V, respectively; the keys to our success are listed in Section V 相似文献
108.
Naor MM Walker MD Van Brocklyn JR Tigyi G Parrill AL 《Journal of molecular graphics & modelling》2007,26(2):519-528
The dissociation constant for an ionizable ligand binding to a receptor is dependent on its charge and therefore on its environmentally-influenced pKa value. The pKa values of sphingosine 1-phosphate (S1P) were studied computationally in the context of the wild type S1P1 receptor and the following mutants: E3.29Q, E3.29A, and K5.38A. Calculated pKa values indicate that S1P binds to S1P1 and its site mutants with a total charge of -1, including a +1 charge on the ammonium group and a -2 charge on the phosphate group. The dissociation constant of S1P binding to these receptors was studied as well. The models of wild type and mutant proteins originated from an active receptor model that was developed previously. We used ab initio RHF/6-31+G(d) to optimize our models in aqueous solution, where the solvation energy derivatives are represented by conductor-like polarizable continuum model (C-PCM) and integral equation formalism polarizable continuum model (IEF-PCM). Calculation of the dissociation constant for each mutant was determined by reference to the experimental dissociation constant of the wild type receptor. The computed dissociation constants of the E3.29Q and E3.29A mutants are three to five orders of magnitude higher than those for the wild type receptor and K5.38A mutant, indicating vital contacts between the S1P phosphate group and the carboxylate group of E3.29. Computational dissociation constants for K5.38A, E3.29A, and E3.29Q mutants were compared with experimentally determined binding and activation data. No measurable binding of S1P to the E3.29A and E3.29Q mutants was observed, supporting the critical contacts observed computationally. These results validate the quantitative accuracy of the model. 相似文献
109.
Etienne Urbah Peter Kacsuk Zoltan Farkas Gilles Fedak Gabor Kecskemeti Oleg Lodygensky Attila Marosi Zoltan Balaton Gabriel Caillat Gabor Gombas Adam Kornafeld Jozsef Kovacs Haiwu He Robert Lovas 《Journal of Grid Computing》2009,7(3):335-354
Desktop Grids, such as XtremWeb and BOINC, and Service Grids, such as EGEE, are two different approaches for science communities to gather computing power from a large number of computing resources. Nevertheless, little work has been done to combine these two Grid technologies in order to establish a seamless and vast Grid resource pool. In this paper we present the EGEE Service Grid, the BOINC and XtremWeb Desktop Grids. Then, we present the EDGeS solution to bridge the EGEE Service Grid with the BOINC and XtremWeb Desktop Grids. 相似文献
110.
Klein Daniel N.; Santiago Neil J.; Vivian Dina; Blalock Janice A.; Kocsis James H.; Markowitz John C.; McCullough James P. Jr.; Rush A. John; Trivedi Madhukar H.; Arnow Bruce A.; Dunner David L.; Manber Rachel; Rothbaum Barbara; Thase Michael E.; Keitner Gabor I.; Miller Ivan W.; Keller Martin B. 《Canadian Metallurgical Quarterly》2004,72(4):681
Although the efficacy of maintenance pharmacotherapy for the prevention of recurrence in major depressive disorder (MDD) is well documented, few studies have tested the efficacy of psychotherapy as a maintenance treatment. The authors examined the efficacy of the cognitive-behavioral analysis system of psychotherapy (CBASP) as a maintenance treatment for chronic forms of MDD. Eighty-two patients who had responded to acute and continuation phase CBASP were randomized to monthly CBASP or assessment only for 1 year. Significantly fewer patients in the CBASP than assessment only condition experienced a recurrence. The 2 conditions also differed significantly on change in depressive symptoms over time. These findings support the use of CBASP as a maintenance treatment for chronic forms of MDD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献