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1.
分析了排风扇前盖塑件的工艺特点,介绍了排风扇前盖注射成型模结构及模具的工作过程。  相似文献   
2.
The proposed work involves the multiobjective PSO based adaption of optimal neural network topology for the classification of multispectral satellite images. It is per pixel supervised classification using spectral bands (original feature space). This paper also presents a thorough experimental analysis to investigate the behavior of neural network classifier for given problem. Based on 1050 number of experiments, we conclude that following two critical issues needs to be addressed: (1) selection of most discriminative spectral bands and (2) determination of optimal number of nodes in hidden layer. We propose new methodology based on multiobjective particle swarm optimization (MOPSO) technique to determine discriminative spectral bands and the number of hidden layer node simultaneously. The accuracy with neural network structure thus obtained is compared with that of traditional classifiers like MLC and Euclidean classifier. The performance of proposed classifier is evaluated quantitatively using Xie-Beni and β indexes. The result shows the superiority of the proposed method to the conventional one.  相似文献   
3.
加氢反应器是加氢装置的重要组成部分,反应器头盖因工况复杂,导致密封难度较大,密封不严,会导致整个装置不能正常运转。为此,就其头盖拆装及密封问题进行探讨,提出有效的质量控制措施。  相似文献   
4.
In Malaysia, no long-term daylight data are measured. It was only recently that the need to measure the availability of daylight became urgent when the importance of daylighting in buildings was rediscovered. The hourly daylight availability has been simulated for the Malaysian sky using daylight modelling techniques based on empirical and measured solar irradiation and cloud cover data. This paper presents the techniques involved in producing exterior illuminance data. These data were then compared with measured illuminance at Shah Alam and Bangi, Malaysia. The global illuminance levels are generally high, with values exceeding 80,000 lux at noon during the months when solar irradiation is highest. Even during the months when the ground receives less solar irradiation, the peak illuminance can reach 60,000 lux. Applications and uses of such data are in daylighting design, both for visual and thermal comfort, task illuminance and energy-conscious design of buildings. Recommendations are made at the end of the paper on the various climatic data that are required to be measured for overall daylighting design applications.  相似文献   
5.
1 IntroductionThestickingpointofassociationrulealgorithmsdependsoneffectivelyfindingallcorrelationpatternsthatsatisfyvaluerequirementinthemagnanimityofdata.Butthealgorithmsalsobringanegativeef fect:thenumberofassociationrulesisverylarge.Alsoinformation…  相似文献   
6.
介绍焦化行业钛设备的应用,剖析了分块式钛泡罩塔盘的结构特点,并对其经济性作了分析。  相似文献   
7.
阜阳电厂粉煤灰综合利用可行性研究   总被引:3,自引:0,他引:3  
结合阜阳地区实际情况,从目前成熟的粉煤灰利用途径中,选择制水泥、建粉磨站、生产非煅烧粉煤灰轻骨料、轻质小砌块,以及筑路回填、灰场种植等处理利用项目,达到节约土地并获得好的经济效益和环境效益  相似文献   
8.
大变量逻辑函数最佳覆盖问题研究   总被引:2,自引:0,他引:2  
逻辑函数的最佳覆盖,一直是逻辑综合领域的关键环节。尤其是大变量逻辑函数最佳覆盖,对复杂的逻辑综合更为重要,但也更加困难。本文在对逻辑覆盖算法研究的基础上,提出了适合大变量逻辑函数最佳覆盖的Beister改进算法。经过大量算题的测试表明,改进的列覆盖算法在时间复杂度和选择效果方面均优于Beister算法。  相似文献   
9.
Magnesium-lithium alloys are among the lowest density metallic materials. Addition of lithium, with a relative density of 0·53, in magnesium reduces the density of the alloy significantly. Furthermore, addition of nearly 11 wt.% lithium converts hexagonal close packed structure of pure magnesium to a body centered cubic lattice, markedly improving formability of the alloy. The development of these alloys, however, had been hampered due to the high reactivity of lithium and magnesium in the molten state and also, due to poor creep resistance and instability of mechanical properties at room temperature. In an attempt to indigenize these ultra light alloys for possible applications in Indian satellite programme, detailed research work was initiated in DMRL. The difficulties associated with producing sound cast ingots have been overcome by controlling melting and casting parameters of these alloys. Extensive work has been done on structure-property correlation of alloys with varying lithium content and minor alloying additions. Based on these work, advanced magnesium-lithium alloys have been developed with improved tensile properties, room temperature stability and creep resistance. Wrought products (plates/sheets) of magnesium-lithium alloy have been supplied to ISAC, Bangalore and are being used in their INSAT-2 programme. This paper describes the systematic studies carried out in the laboratory to indigenize these ultra light alloys.  相似文献   
10.
Monitoring of nitrate (NO3-) and nitrite (NO2-) content in agricultural products in Slovenia has been carried out since 1996. The results of monitoring over the period 1996-2002 are presented. During this time 924 samples of 14 different agricultural products (potato, lettuce, apples, carrot, silage maize, cabbage, grapes, peaches, string beans, cereals, pears, cucumbers, strawberries and tomato) were analysed. The samples were taken at the time of maturity directly from growing sites and they were analysed using segmented flow analysis. The average nitrate contents were the highest in lettuce (1074 mg kg-1), cabbage (881 mg kg-1), string beans (298 mg kg-1) and carrot (264 mg kg-1), and they were moderately high in potato (158 mg kg-1), silage maize (122 mg kg-1), strawberries (94 mg kg-1), cucumbers (93 mg kg-1) and cereals (49 mg kg-1). Low nitrate contents (below 6 mg kg-1) were found in fruit (grapes, peaches, apples and pears) and tomato. With the exception of cereals (8.9 mg kg-1), apples (1.5 mg kg-1), potato (1.2 mg kg-1) and pears (1.0 mg kg-1) the content of nitrites did not exceed 0.5 mg kg-1. It may be concluded that the results of the monitoring were in most cases similar to the results of investigations obtained in other countries.  相似文献   
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