基于LabVIEW的光栅单色仪控制

设计一种LabVIEW环境下光栅单色仪的步进电机控制方法。详细阐述该系统的总体设计,程序设计和步进电机驱动电路设计。     

"Network interference and number-fact retrieval: Evidence from children's alphaplication": Erratum.

Reports an error in "Network interference and number-fact retrieval: Evidence from children's alphaplication" by D. Jeffrey Graham and Jamie I. Campbell (Canadian Journal of Psychology Revue Canadienne de Psychologie, 1992[Mar], Vol 46[1], 65-91). Figure 1 was inadvertently omitted. Reprints of this article, available from the authors, will include this figure. (The following abstract of the original article appeared in record 1992-42555-001.) Investigated the origins of several phenomena of number-fact retrieval by asking 45 children (aged 8 yrs 2 mo to 10 yrs 7 mo) to memorize alphaplication facts (arithmetic-like memory items composed of letters instead of numbers). Ss' performance in the task showed paralleled aspects of simple arithmetic performance. There was a strong performance advantage for tie over nontie problems on both reaction time (RT) and errors. Specific errors frequently involved operand-related answers. Correct RTs and error rates across problems were closely linked. Correct answers to poorly learned problems tended to be the most common error responses. Performance was not as good for problems that were introduced later in the learning sequence. Results support the network-interference approach to number-fact retrieval of J. I. Campbell and D. J. Graham (see record 1986-16912-001). (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于LabVIEW8.2的多用虚拟电压表设计

为了满足不同测量的要求传统的电压表分别做成独立的仪表,包括峰值电压表、平均值电压表和有效值电压表.在此,提出采用虚拟仪器同时实现三种示值电压表的方案;介绍了虚拟仪器软件平台LabVIEW的特点.对虚拟数字电压表的设计和实现进行了详细描述,包括基于LabVIEW 8.2的虚拟信号发生器的实现过程,它能产生正弦、方波、三角波及由输入数学公式确定的复杂自编辑波形.最后,对设计的虚拟电压表运行结果进行分析,验证了虚拟电压表设计方法的正确性.     

超大采高工作面液压支架与围岩耦合作用关系

针对金鸡滩煤矿坚硬厚煤层赋存条件,提出了8.2 m超大采高一次采全厚开采方法,分析了超大采高工作面液压支架与围岩的强度、刚度、稳定性耦合关系及控制方法,研制了ZY21000/38/82D型超大采高液压支架及新结构。基于液压支架与围岩耦合作用关系,采用理论分析与数值模拟方法研究了超大采高液压支架合理工作阻力确定的“双因素”控制法;通过建立脆性坚硬厚煤层煤壁片帮的“拉裂-滑移”力学模型,得出了控制煤壁片帮发生滑移失稳的液压支架临界护帮力;分析了销轴铰接间隙对超大采高液压支架稳定性的影响及控制方法。通过创新研制大缸径抗冲击双伸缩立柱、三级协动护帮装置等新结构,保证了超大采高液压支架与围岩系统的稳定性控制。     

基于虚拟仪器的汽车仪表设计

以PC机、NI公司PCI-6221板卡、NI信号调理模块（应变、RTD、TC等）为硬件平台,以CSY．200（IC传感器与测控技术实验台为测控对象,以LabVIEW8．2为软件开发平台,设计汽车虚拟数字化仪表模拟机,可以实现日期／时间、总里程、当前速度、转速、温度、油箱存油量等信息的显示,实现汽车仪表的校验和标定。     

数字多用表自动化测试系统的应用

介绍数字多用表自动化测试系统的组成、工作原理和该系统可实现的功能,以34401A数字多用表为例,分析测试系统对该表的测试情况,并同手动检定结果进行对比,指出该套测试系统具有可行性,同时提出应用中的注意事项。     

Challenges and opportunities in improving the production of bio-ethanol

Bio-ethanol, as a clean and renewable fuel, is gaining increasing attention, mostly through its major environmental benefits. It can be produced from different kinds of renewable feedstock such as e.g. sugar cane, corn, wheat, cassava (first generation), cellulose biomass (second generation) and algal biomass (third generation). The conversion pathways for the production of bio-ethanol from disaccharides, from starches, and from lignocellulosic biomass are examined. The common processing routes are described, with their mass and energy balances, and assessed by comparing field data and simulations. Improvements through 5 possible interventions are discussed, being (i) an integrated energy-pinch of condensers and reboilers in the bio-ethanol distillation train; (ii) the use of Very High Gravity (VHG) fermentation; (iii) the current development of hybrid processes using pervaporation membranes; (iv) the substitution of current ethanol dewatering processes to >99.5 wt% pure ethanol by membrane technology; and (v) additional developments to improve the plant operation such as the use of microfiltration of the fermenter broth to protect heat exchangers and distillation columns against fouling, or novel distillation concepts.Whereas the benefits of introducing these techniques are recognized, extensive research is still needed to scientifically and economically justify their application. The paper finally presents a tentative economic assessment, with production costs not only depending on the extent of applying process improvements, but also on the raw material used in the process.     

碳团簇型材料/环氧树脂复合材料吸波性能研究

The effects of the amount and dimension of carbon cluster-like absorber on the composite material have been studied. As the result, the material with excellent microwave absorbing capability has been attained. The material with density of 1.16g/cm^3 and thickness of 2 mm achieves maximum absorbing value of --27dB, and the minimum value of --10dB over the whole fre-quency ranges of 8.2～ 12.4GHz. The absorbing mechanism is discussed using the electromagnetic wave theory.     

基于虚拟仪器的直流电压表设计

随着电子科学技术的发展,电子测量成为广大电子工作者必须掌握的手段,同时对测量仪器的精度和功能的要求也越来越高,而对电压量的测量要求更为突出。在参阅了大量前人设计的数字电压表的基础上,本文利用虚拟仪器技术构建了一个直流数字电压表。硬件设计采用DAQ体系结构并采用LabVIEW8.2软件平台进行软件设计。经过分析系统性能可靠,测试灵活,人机交互性强,可以达到测试者的要求。     

基于虚拟仪器的汽车仪表设计

以PC机、NI公司PCI-6221板卡、NI信号调理模块(应变、RTD、TC等)为硬件平台,以CSY-2000C传感器与测控技术实验台为测控对象,以LabVIEW8.2为软件开发平台,设计汽车虚拟数字化仪表模拟机,可以实现日期/时间、总里程、当前速度、转速、温度、油箱存油量等信息的显示,实现汽车仪表的校验和标定。