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21.
Design tool integration is a highly relevant area of software engineering that can greatly improve the efficiency of development processes. Design patterns have been widely recognized as important contributors to the success of software systems. This paper describes and compares two large-grain, architectural design patterns that solve specific design tool integration problems. Both patterns have been implemented and used in real-life engineering processes.  相似文献   
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There is currently considerable interest in the development of fluidized-bed boilers for efficient and environmentally clean combustion of coal. Fluidized beds have the advantages of high heat transfer rates and intimate mixing of additives such as limestone or dolomite for sulfur dioxide absorption produced as a result of combustion of coal containing sulfur. However, design for optimum heat transfer remains uncertain and essentially empirical. The mechanisms of heat transfer are complicated because of the many variables in a commercial combustion operation such as particle size distribution, particle shape, particle and gas thermal properties, reactor geometry and boiler tube design.An understanding of the mechanisms of bed to tube heat transfer is essential to sound design and interpretation of empirically derived correlations. Here we will review and criticize the major mechanisms of heat transfer that have been proposed. These mechanisms are proposed and developed from two schools of thought: (a) The principal resistance to heat transfer is a fluid film, and the moving fluidized particles scour the film to reduce the resistance to heat transfer; (b) Heat is absorbed by the fluidized particles and the rate of heat transfer depends on the rate of heat absorption.Radiant heat transfer is also discussed in this review in detail. Heat transfer by radiation is an important consideration in combustors but has received limited attention. The results of theoretical calculations are given which have been recently reported on the basis of the alternate-slab model of Gabor.The review will predominantly deal with the mechanistic models of heat transfer and various correlations developed over years will not be covered as this topic is dealt with in another review article by Saxena, Grewal, Gabor, Zabrodsky and Galershtein.  相似文献   
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The diffuse reflection (DR) spectrum of a sample consisting of a mixture of rare earth oxides and talc was measured at 2 cm-1 resolution, using five different accessories installed on five different Fourier transform near-infrared (FT-NIR) spectrometers from four manufacturers. Peak positions for 37 peaks were determined using two peak-picking algorithms: center-of-mass and polynomial fitting. The wavenumber of the band center reported by either of these techniques was sensitive to the slope of the baseline, and so the baseline of the spectra was corrected using either a polynomial fit or conversion to the second derivative. Significantly different results were obtained with one combination of spectrometer and accessory than the others. Apparently, the beam path through the interferometer and DR accessory was different for this accessory than for any of the other measurements, causing a severe degradation of the resolution. Spectra measured on this instrument were removed as outliers. For measurements made on FT-NIR spectrometers, it is shown that it is important to check the resolution at which the spectrum has been measured using lines in the vibration-rotation spectrum of atmospheric water vapor and to specify the peak-picking and baseline-correction algorithms that are used to process the measured spectra. The variance between the results given by the four different methods of peak-picking and baseline correction was substantially larger than the variance between the remaining five measurements. Certain bands were found to be more suitable than others for use as wavelength standards. A band at 5943.13 cm-1 (1682.62 nm) was found to be the most stable band between the four methods and the six measurements. A band at 5177.04 cm-1 (1931.61 nm) has the highest precision between different measurements when polynomial baseline correction and polynomial peak-picking algorithms are used.  相似文献   
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Designing autonomic fault responses is difficult, particularly in large-scale systems, as there is no single ‘perfect’ fault mitigation response to a given failure. The design of appropriate mitigation actions depend upon the goals and state of the application and environment. Strict time deadlines in real-time systems further exacerbate this problem. Any autonomic behavior in such systems must not only be functionally correct but should also conform to properties of liveness, safety and bounded time responsiveness. This paper details a real-time fault-tolerant framework, which uses a reflex and healing architecture to provide fault mitigation capabilities for large-scale real-time systems. At the heart of this architecture is a real-time reflex engine, which has a state-based failure management logic that can respond to both event- and time-based triggers. We also present a semantic domain for verifying properties of systems, which use this framework of real-time reflex engines. Lastly, a case study, which examines the details of such an approach, is presented.  相似文献   
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The trienoic and tetraenoic polyenes, (3Z,6Z,9Z)-3,6,9-nonadecatriene, (3Z,6Z,9Z)-3,6,9-henicosatriene, and (3Z,6Z,9Z)-1,3,6,9-henicosatetraene were found in the abdominal cuticle and pheromone gland of the winter moth Operophtera brumata L. (Lepidoptera: Geometridae), in addition to the previously identified single component sex pheromone (3Z,6Z,9Z)-1,3,6,9-nonadecatetraene. The pheromone biosynthesis activating neuropeptide (PBAN) is involved in the regulation of polyene transport from abdominal cuticle to the pheromone gland. In vivo deuterium labeling experiments showed that (11Z,14Z,17Z)-11,14,17-icosatrienoic acid, the malonate elongation product of linolenic acid, (9Z,12Z,15Z)-9,12,15-octadecatrienoic acid, is used to produce (3Z,6Z,9Z)-3,6,9-nonadecatriene and (3Z,6Z,9Z)-1,3,6,9-nonadecatetraene.  相似文献   
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For the general calculation of the transformation of steels the transformation diagram for isothermal transformation must be known. It is described, how from dilatometric measurements with continuous cooling the transformation at a constant temperature can be calculated. To do this, the simplex method must be used as iteration process to achieve sufficient precision. Even when measuring data are scattered around an ideal value by ±5% the transformation diagram for isothermal transformation can be calculated with considerable accuracy.  相似文献   
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