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Yih JN  Hsu WC  Tsai SY  Chen SJ 《Applied optics》2005,44(15):3001-3005
We present a study in which we enhance the carrier-to-noise ratio of a superresolution near-field structure (super-RENS) disk to read below 100-nm marks by implementing a mask layer comprising a Au nanocluster-embedded dielectric film. Various Au nanocluster-embedded mask layers are fabricated by a radio-frequency cosputtering process, and the size and distribution of Au nanoclusters are controlled. To verify the enhancement of the various films for super-RENS disk applications, the sensitivity enhancement of plasmonic gas sensing is demonstrated.  相似文献   
998.
A frame-based technique, including physical frame, logical frame, and cognitive frame, was adopted to perform digital I&C failure events derivation and analysis for generic ABWR. The physical frame was structured with a modified PCTran-ABWR plant simulation code, which was extended and enhanced on the feedwater system, recirculation system, and steam line system. The logical model is structured with MATLAB, which was incorporated into PCTran-ABWR to improve the pressure control system, feedwater control system, recirculation control system, and automated power regulation control system. As a result, the software failure of these digital control systems can be properly simulated and analyzed. The cognitive frame was simulated by the operator awareness status in the scenarios. Moreover, via an internal characteristics tuning technique, the modified PCTran-ABWR can precisely reflect the characteristics of the power-core flow. Hence, in addition to the transient plots, the analysis results can then be demonstrated on the power-core flow map. A number of postulated I&C system software failure events were derived to achieve the dynamic analyses. The basis for event derivation includes the published classification for software anomalies, the digital I&C design data for ABWR, chapter 15 accident analysis of generic SAR, and the reported NPP I&C software failure events. The case study of this research includes: (1) the software CMF analysis for the major digital control systems; and (2) postulated ABWR digital I&C software failure events derivation from the actual happening of non-ABWR digital I&C software failure events, which were reported to LER of USNRC or IRS of IAEA. These events were analyzed by PCTran-ABWR. Conflicts among plant status, computer status, and human cognitive status are successfully identified. The operator might not easily recognize the abnormal condition, because the computer status seems to progress normally. However, a well trained operator can become aware of the abnormal condition with the inconsistent physical parameters; and then can take early corrective actions to avoid the system hazard. This paper also discusses the advantage of simulation-based method, which can investigate more in-depth dynamic behavior of digital I&C system than other approaches. Some unanticipated interactions can be observed by this method.  相似文献   
999.
The Southwest Oncology Group has confirmed the superiority of 5-fluorouracil (5-FU) and methyl-CCNU versus 5-FU weekly as treatment for patients with advanced gastrointestinal cancers. The drug combination produced a PR rate of 29.3% compared to the single-drug arm rate of 10.6%; however, the two-drug arm produced much more toxicity. Despite the improved response rate no improvement in survival was observed.  相似文献   
1000.
With a view to simplifying the separation of haemopoietic stem cell concentrates from human peripheral blood, in preparation for their clinical use, the production of lymphocyte concentrates by cotton wool filtration has been investigated. Using the method which is described in detail, highly purified suspensions may be prepared without the selective loss of thymus-independent lymphocytes. Optimal operating conditions are defined. Haemopoietic stem cell concentrates may thereby be harvested, and are shown to be capable of proliferation and differentiation on subsequent culture in vivo.  相似文献   
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