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991.
The paper briefly reviews the major forms of optical bistability in active optical devices compatible for use in gigabit optical communication systems, and reports an entirely new optical bistability for the first time. Unlike previous devices, the two bistable states of the optical device are each a series of picosecond optical pulses at 1 GHz or greater repetition rates, and are distinguished by a half period temporal shift between their temporal positions in relation to a clock pulse. The bistable device is based on a gain switched semiconductor laser. Theoretical studies suggest 100-ps switching speeds might be achieved, and experimental results are reported indicating optically triggered switching times of 500 ps.  相似文献   
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996.
A risk approach to the management of boiler tube thinning   总被引:1,自引:0,他引:1  
A large set of industrial thickness inspection data covering four boiler units of a power station over a period of five years was made available to the authors. The measurements were made in regions of the boiler where corrosion/erosion was the major cause of failure of the boiler tubes. There were over 40,000 separately measured data points in the data and all were collected with some care and expense.In the development of maintenance strategies for equipment, this type of data is typical of the data that must be collected and assessed. This data thus represents an opportunity to evaluate the ability to generate a useful risk approach to the management of the tubing.An important example of a risk-based approach is the American Petroleum Institute (API) Risk Based Inspection (“RBI”), API 581. A variety of problems were encountered applying this to boiler tubes. The problems include irrelevant API 581 corrosion rate tables, lack of information on how to analyse inspection data, difficulty of dealing with multiple inspection categories and lack of suitable direction for programming inspection intervals.  相似文献   
997.
Results are presented from extensive comparison studies of drawing operations performed with the use of drawplates whose working surfaces have an irregular or regular microroughness. Regularizing the microroughness of the working part of the drawplate makes it possible to control the dimensional accuracy of the resulting products within broad ranges of values.  相似文献   
998.
能源成本上涨速度高于纱线价格上涨速度,Autocoro纺纱厂每年的能耗成本约占每年营业额的5%,主要能耗是电能.  相似文献   
999.
A circuit design is proposed and the possibilities for incorporation of an input double-notch low-frequency ripple filter are considered. Recommendations regarding the use of mathematical models for the calculation of transient processes in a DC electric-traction network are given. An analysis of the simulation of processes in a low-frequency filter shows that the emission of interference by the electric rolling stock should be estimated using the wavelet analysis since this approach best suits the studies of nonstationary signals.  相似文献   
1000.
The design principals of fast-operating electromagnetic drives with prescribed dynamic performances are examined. The represented procedure permits the command parameters to be to determined with the guaranteed prescribed parameters of the drive.  相似文献   
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