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91.
One of the main advantages of defining a domain-specific modeling language (DSML) is the flexibility to adjust the language definition to changing requirements or in response to a deeper understanding of the domain. With the industrial applications of domain-specific modeling environments, models are valuable investments. If the modeling language evolves, these models must be seamlessly migrated to the evolved DSML. Although the changes stemming from the language evolution are not abrupt in nature, migrating existing models to a new language is still a challenging task. Our solution is the Model Change Language (MCL) tool set, which defines a DSML to describe the migration rules and then performs the model migration automatically. In this paper, we describe the precise semantics of MCL and its execution, along with the confluence of the migration.  相似文献   
92.
The Front End Test Stand (FETS) is located at Rutherford Appleton Laboratory and aims for a high current, fast chopped 3 MeV H(-) ion beam suitable for future high power proton accelerators like ISIS upgrade. The main components of the front end are the Penning ion source, a low energy beam transport line, an radio-frequency quadrupole (RFQ) and a medium energy beam transport (MEBT) providing also a chopper section and rebuncher. FETS is in the stage of commissioning its low energy beam transport (LEBT) line consisting of three solenoids. The LEBT has to transport an H(-) high current beam (up to 60 mA) at 65 keV. This is the injection energy of the beam into the RFQ. The main diagnostics are slit-slit emittance scanners for each transversal plane. For optimizing the matching to the RFQ, experiments have been performed with a variety of solenoid settings to better understand the actual beam transport. Occasionally, source parameters such as extractor slit width and beam energy were varied as well. The paper also discusses simulations based on these measurements.  相似文献   
93.
OBJECTIVE: Signal pattern enumeration of Urovysion Fluorescence in Situ Hybridization test is tedious and requires great experience. Our aim was to eliminate human interaction by automating the process, using an adoptable, automated image acquisition, and analysis system. METHODS: For extensive analytical analysis control, cell populations were used, while preliminary clinical study was performed on 21 patients with clinical suspicion for bladder cancer. All investigations were carried out using an automated user‐trainable workstation (Metafer4‐Metacyte). RESULTS: The system identified nuclei with a specificity and sensitivity of 92.7 and 96.6%, respectively, while signal detection accuracy was 81.1% on average. Both analytical and diagnostic accuracy of automated analysis was comparable to manual approach (94.8 and 71% vs. 97.9 and 76%, respectively), but classification accuracy increased with degree of polysomy, thus diagnostic sensitivity in low grade, low stage cases was poor. CONCLUSION: It is possible to automate signal enumeration of Urovysion using a user‐trainable system, and achieve efficiency comparable to manual analysis. Previously introduced automated immunophenotypic targeting should further increase diagnostic sensitivity, while resulting in a comprehensively automated method. However, the problem of reduced detection accuracy in cases featured with low polysomy is likely to remain a great challenge of automated signal enumeration. Microsc. Res. Tech. 75:814–820, 2012. © 2011 Wiley Periodicals, Inc.  相似文献   
94.
This work aims to summarize predictive biomarkers to guide treatment choice in DME. Intravitreal anti-VEGF is considered the gold standard treatment for centers involving DME, while intravitreal steroid treatment has been established as a second-line treatment in DME. However, more than 1/3 of the patients do not adequately respond to anti-VEGF treatment despite up to 4-weekly injections. Not surprisingly, insufficient response to anti-VEGF therapy has been linked to low-normal VEGF levels in the serum and aqueous humor. These patients may well benefit from an early switch to intravitreal steroid treatment. In these patients, morphological biomarkers visible in OCT may predict treatment response and guide treatment decisions. Namely, the presence of a large amount of retinal and choroidal hyperreflective foci, disruption of the outer retinal layers and other signs of chronicity such as intraretinal cysts extending into the outer retina and a lower choroidal vascular index are all signs suggestive of a favorable treatment response of steroids compared to anti-VEGF. This paper summarizes predictive biomarkers in DME in order to assist individual treatment decisions in DME. These markers will help to identify DME patients who may benefit from primary dexamethasone treatment or an early switch.  相似文献   
95.
96.
ABSTRACT

Spectroscopic applications of the recently described method of arc lamp stabilization by the addition of a small (<2v) alternating current (AC) to a direct current (DC) arc lamp are discussed. A possible explanation for the improved arc stability is presented. Evaluation of arc formation and spatial behavior is monitored by a series of still photographs of the arc image. Observation of the electrode surfaces in similar photographs provide insight into the distribution of heat in the inter-electrode region. A photodiode array imaging device is used to accurately detect lateral movement of the arc image over prolonged time periods. Advantages of AC stabilized lamps in spectroscopic applications are also presented.  相似文献   
97.
An oversampled digital-to-analog converter (DAC) with a 100-dB A-weighted dynamic range is presented. It uses a switched-capacitor (SC) array to transfer the sampled charges directly into the headphone driver. The overall DAC gain is precisely controlled by a novel reference stage. A new dynamic element matching algorithm, based on split-set data-weighted averaging (SDWA), is used to improve the dynamic range and to reduce the nonlinearity caused by mismatches in the multibit DAC.  相似文献   
98.
99.
Wellfield B, in the Great Artesian Basin (GAB), supplies 30 ML/day of fresh groundwater to BHP Billiton’s Olympic Dam mine and the town of Roxby Downs in South Australia. Groundwater use from Wellfield B is regulated according to the regional effects on pressures in the aquifer. Drawdown assessment criteria (allowing a maximum of 5?m as pressure drawdown measured in piezometers) were set at five sites, including two active pastoral production wells that existed prior to the commissioning of Wellfield B. Aquifer pressure in these production wells was measured after a predetermined recovery time. Pastoral flow was eliminated in 2009/10 in one of the wells, providing an opportunity to assess whether antecedent flow had affected the measured pressures and therefore the reported apparent drawdown. In the GAB, the combination of deep wells, high pressures, and hot water make flow and pressure measurements and the calculation of head more challenging than in cold aquifers. Pressures measured at the well head often decrease during recovery, and the influence of temperature has to be incorporated in head calculations. Based on one example, Jackboot Bore, it is clear that recovery times in the order of months are required, which is impractical. Hence, the use of an active production well for assessing compliance with drawdown criteria is not recommended in the GAB.  相似文献   
100.
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   
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