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31.
Jorge Barrios Alain Piétrus Gonzalo Joya Aymée Marrero Héctor de Arazoza 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2013,17(2):239-253
In this paper we deal with the application of differential inclusions to modeling nonlinear dynamical systems under uncertainty in parameters. In this case, differential inclusions seem to be better suited to modeling practical situations under uncertainty and imprecision than formulations by means of fuzzy differential equations. We develop a practical algorithm to approximate the reachable sets of a class of nonlinear differential inclusion, which eludes the computational problems of a previous set-valued version of the Heun’s method. Our algorithm is based on a complete discretization (time and state space) of the differential inclusion and it suits hardware features, handling the memory used by the method in a controlled fashion during all iterations. As a case of study, we formulate a differential inclusion to model an epidemic outbreak of dengue fever under Cuban conditions. The model takes into account interaction of human and mosquito populations as well as vertical transmission in the mosquito population. It is studied from the theoretical point of view to apply the Practical Algorithm. Also, we estimate the temporal evolution of the different human and mosquito populations given by the model in the Dengue 3 epidemic in Havana 2001, through the computation of the reachable sets using the Practical Algorithm. 相似文献
32.
Meng‐Hui Wang Pi‐Chu Wu Wei‐Jhe Jiang 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(4):479-486
Distribution panels are an important piece of equipment in power systems. Maintaining a loading panel and ensuring security are not easy because the power supply cannot be interrupted in high‐tech factories. Distribution panels need fully functional condition monitoring and fault diagnosis systems to prevent accidents and reduce maintenance costs. In this paper, a new scheme is proposed to design an auto‐diagnosis tool for electrical distribution panels using infrared thermography to build diagnostic features using the matter‐element model. The paper then presents an extension recognize method (ERM) based on extension theory to diagnose the abnormality element by using degrees of correlation between the tested pattern and the matter‐element models that have been built up. Test results show that the proposed method can not only recognize the main defect element of the tested panel but also detect useful information for future trends and multi‐defect analysis by the correlation indexes. This new approach merits more attention as a tool to be used in the defect recognition problems of distribution panels, especially in high‐tech factories in Taiwan. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
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Sho Kano Huilong Yang John McGrady Tomonori Ihara Hazuku Tatsuya Hiroaki Abe 《Journal of Nuclear Science and Technology》2019,56(3):300-309
The radiation-induced surface activation (RISA) effect will be applied to the core design in supercritical light water reactor (SCWR) in order to achieve a high performance with excellent economy and safety. The purpose of the present study is to investigate the RISA effect in the candidate fuel cladding materials in SCWR such as PNC1520. The change of weldability due to RISA effect and the related microstructure analysis were performed in oxidized PNC1520 and 304 stainless steel with various oxidization periods. The phases contained in the surface oxide layer of the present specimen were identified as Fe2CrO4, γ-Fe2O3, and Fe2O3. The lifetime of 13.8 days for wettability improving factor was confirmed in the ultraviolet (UV) irradiation. Meanwhile, the long life of 13.8 days and short life of 0.8 days for wettability improving factors were identified in the γ-ray irradiation. Based on the fact that the band gap energies of Fe2CrO4, γ-Fe2O3, and Fe2O3 were, respectively, 2.1, 2.0, and 2.2 eV, and the photo energies of UV and γ-ray irradiation were 4.48 eV and 13.3 MeV, it is therefore clarified that the hydrophilization on the oxide layer is ascribed to the RISA effect. 相似文献
35.
新闻纸的白度、色度与不透明度 总被引:1,自引:0,他引:1
本文通过对目前新闻纸市场上新闻纸的白度、色度和不透明度的调查,结合本厂的实践提出了对新闻纸的ISO白度、CIE白度、L^*、a^*、b^*值和不透明度的合理控制范围。 相似文献
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挠性摆式微硅加速度计的有限元分析 总被引:4,自引:1,他引:4
】微硅加速度计是近年来发展起来的新型器件,在结构设计阶段必须对其进行力学分析,以期对使用条件下的摆片位移、应力等作到心中有数。本文采用有限元分析方法对挠性摆式微硅加速度计进行有限元分析,其中包括对未封装及封装后实体单元进行敏感轴位移、侧向位移、横向灵敏度、受力情况等分析。分析结果表明所设计的微硅加速度计符合仪表性能要求。 相似文献
40.
为提高纤维状超级电容器的电容性能,将碳纳米管(CNT)纤维进行阳极氧化预处理、金属化处理和电沉积聚苯胺后得到不同的电极材料,分别将CNT、CNT/聚苯胺(CNT-PANI)、CNT/阳极氧化/聚苯胺(CNT-O-PANI)、CNT/阳极氧化/金属化/聚苯胺(CNT-O-Ni-PANI)这4种电极材料组装纤维状超级电容器,并对其结构和电化学性能进行研究。结果表明:经过阳极氧化和金属化处理后,聚苯胺均匀、紧密地分散在碳纳米管纤维表面,并且无团聚、结块等现象;CNT-O-Ni-PANI电极材料制备的超级电容器具有优异的储能性能,其比电容和能量密度远高于其他3种电极材料;在1 A/g的电流密度下,其比电容和能量密度分别为357.8 F/g和178.9 W·h/kg;在10 mV/s的扫速下,其比电容高达1 246.3 F/g;采用CNT-O-Ni-PANI所制备的超级电容器稳定性能较好,在5 A/g的电流密度下,经过10 000次恒流充放电循环后,其电容保持率仍高达99.7%。 相似文献