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1.
《International Journal of Hydrogen Energy》2020,45(30):15196-15212
This paper introduces a novel Coke Oven Gas (COG) hydrogen purification/compression system based on the technologies of Pressure Swing Adsorption (PSA) and Electrochemical Hydrogen Purification and Compression (EHP/C). As the EHP/C tolerates O2, N2 and CH4 impurities, PSA can be utilized solely for CO and CO2 removal (other COG impurities were not considered in this work). A relaxation of PSA hydrogen purity could significantly enhance its recovery rate. In this study, the suitability of traditional hydrogen PSA as part of the hybrid PSA/EHP/C approach was investigated. Aspen Adsorption and Matlab were used to model the PSA and EHP/C systems, respectively. The effect of adsorption pressure, purge-to-feed-ratio (P/F-ratio) and adsorption time within cycle on PSA performance is reported. This study found that breakthrough of non-detrimental components is typically accompanied with poisonous CO. Hence, the CO removal with traditional H2-PSA resulted into high purity product. In a two-bed PSA, 36.3% of hydrogen was recovered at 99.9988% purity and 0.18 ppm CO. Subsequently, as a result, the EHP/C purification capability was merely utilized, but polished this hydrogen to >99.999% purity. Simultaneously, hydrogen was isothermally compressed to 20 MPa, consuming a marginal 2.42 kWh/kg. Compared to mechanical compression, this is 31.6% more energy efficient. Recovering hydrogen from by-product COG was found to save 0.5 kg CO2/kg H2 compared to hydrogen produced from natural gas. Conventional hydrogen PSA, utilizing 70% Activated Carbon and 30% Molecular Sieve 5A, was found not to be effective to target the removal of CO specifically. To increase synergy between PSA and EHP/C, the PSA requires adequate design and operation using appropriate adsorbents and cycle steps to target elimination of CO. An increased EHP/C catalyst tolerance for CO also contributes to higher flexibility. 相似文献
2.
由于铸造厂制芯机器人的工作环境恶劣,机器人抓取砂芯的稳定性较差,时常出现掉砂芯、夹伤砂芯的问题。针对上述问题建立以夹持器、气压、机械振动的系统数学模型,采用高阶系统极点在[s]平面的分布法来判定该系统的稳定性。在确保高阶系统极点值不变的情况下,通过改变系统的零点值来观察零点值对系统稳定性、振荡衰减时间的影响。用Matlab的pzmap和impulse函数分别对系统的零点、极点分布和零点值的不同对系统响应进行仿真,运用仿真结果与现场试验进行优化参数,结果表明采用一种刚度与柔度各为1/2的夹持器对制芯机器人的稳定性具有较好优化效果。 相似文献
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电磁场问题往往较为抽象,并且计算也相对比较复杂。为此,借助计算机软件对复杂问题进行求解的重要性也得到凸显。本文通过两个例子,着重介绍了matlab在电磁场仿真与数值分析中的应用。结果表明这一方法具有计算效率高,能使抽象的场的问题具体化的优点。 相似文献
4.
《Displays》2021
Graphical or Visual User Interface (GUI) is recognized as one of the most important application components for safety critical and business oriented software systems. It is highly advantageous for GUI designers and application developers to analyze the visual complexity of a GUI and predict users’ perception and judgment during the design phase. Although in recent years, various methods have been developed for visual complexity analysis, these have not been widely used due to applicability, practicality and validity issues. In this respect, we have conducted a comprehensive review of studies and methods in visual complexity analysis. After identifying and analyzing 85 research studies, we grouped the visual complexity analysis methods and accordingly a taxonomy is presented. Furthermore, conceptual comparison of the methods is given and gap analysis as well as possible future directions are provided. According to the our findings, major gaps for each visual complexity analysis method may be stated as follows: 1) In metric-model based methods, there is a lack of information about the suitability of the metric-model created for analysis, since the extent to which each metric contributes to visual complexity analysis is still not known exactly. 2) In heuristic- based methods, the extracted rule set is not yet extendable enough beyond the use for specific GUIs. 3) While the visual complexity analysis could be considered as a kind of computer vision task, there exist limited studies that does so. Therefore, generalizable solutions based on machine learning techniques seem to be a promising research direction to develop efficient approaches. 相似文献
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化学信息学是一门利用信息学、计算机科学和技术来解决化学问题的学科。本文利用Matlab科学计算软件的图形用户界面(GUI)功能,通过分子模拟课堂教学的具体实例来展示图形用户界面在化学信息学课程辅助教学中的优点。交互式图形用户界面使得分子模拟过程直观可视化,通过理论与实践教学的结合有助于提高教学质量,激发学习兴趣。 相似文献
8.
分析各种管道评定标准给出不同裂纹情况相应的评价方法,采用GB/T 19624-2004对壁厚为18mm的X80管段长输管道工程实测裂纹进行简化评定,绘制出失效评定图,得出该管道可以安全运行,并给出了最大容许等效裂纹尺寸。对评定过程中的复杂汁算公式进行Matlab软件编程,使得计算过程程序化,提高计算准确率,降低评定难度。 相似文献
9.
装饰混凝土砌块挡土墙的稳定可靠性分析 总被引:2,自引:0,他引:2
通过对装饰混凝土砌块挡土墙进行稳定性分析,以土的自重γ、抗剪强度指标C与",以及砌块的容重为基本随机变量,建立其稳定可靠性计算公式,运用Matlab进行编程,结合实例计算其可靠度。结果十分可靠,可为广大工程设计人员提供装饰混凝土砌块挡土墙的稳定可靠性计算方法。 相似文献
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