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Numerical experiments on nonlinear equations of the 1st and 3rdorder derivatives have been carried out through structural analyses in the phase space according to the numerical instability of illposed systems, with changes of initial values and parameters, etc.. The results show that the quantitative instability in an illposed system may reveal reversed transformation in system evolution by structural representation, and confirm A·Dauglas’ theorem that “a nonlinear equation does not satisfy the existence of the initial value in a linear wellposed system”. 相似文献
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用胺类萃取时,铑以双核的配氯阴离子存在于有机相中,无论用三辛胺,三异辛胺还是N_(1923)萃取时,萃合物的铑氯之比均接近2:9,可用Rh_2Cl_(9~(3-))表示。在此双核配阴离子之中,二个铑原子用三个氯桥相连成,这是一个共面的双八面体,红外光谱中Rh-C1振动峰的分裂证实了这种桥氯键的存在。除了1593cm~(-1)处的Rh-Cl峰之外,在1488cm~(-1)处出现了一个新峰,分裂发生在低频区意味着桥氯键的长度比端氯键长。在类似的双核配氯阴离子如Cr_2Cl_(9~(3-))与W_2Cl_(9~(3-)中,也存在有桥键的伸长。 相似文献
3.
欧阳容百 《南京大学学报(自然科学版)》1987,(4)
本文简要介绍Robertson引入的、适用于非线性区(远离平衡状态)的广义正则统计算符,并给出非平衡态熵的表式。着重运用广义正则统计算符简洁、明了地推证了非平衡热力学中的两个重要定理:最小熵产生定理和超熵判据判据公式。在推导过程中,仅作了局域平衡的假定。 相似文献
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Complex Nuclear Fuel Cycle (NFC) system faces many socio-technical issues that need to obtain the consensus between stakeholders of different knowledge background. In this paper, a visualized analysis platform based on graphical functional modeling method, Multilevel Flow Model (MFM), is proposed to help those stakeholders to recognize and analyze various socio-technical issues in NFC system. Some new functions, such as “Reaction Function”, “Switch Function” and “Conversion Function”, are introduced to fulfill new simulation tasks for NFC system. Based upon this methodology, a micro-process and a macro-process of NFC system are simulated and meanwhile some key analysis variables, such as CO2 emission and cost flow, required by some analysis methods are deducted and displayed in the platform. And finally a sample simulation analysis is conducted based on MFM. 相似文献
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KDD研究中的若干问题与方法 总被引:5,自引:0,他引:5
在数据库中发现知识,又称为数据发掘,其目标是从大型数据集中发现先前未知的潜在有用的模式或知识。本文对该领域进行简要综述,并主要从数据库角度讨论若干数据发掘问题与方法。 相似文献
6.
提出了一种调节滞环宽度、减少有源电力滤波器(APF)的开关损耗的方法.通过比较有源电力滤波器的各相输出参考电流,来调整各相的滞环宽度,以降低开关损耗较大的相的开关动作次数,同时提高开关损耗较小的相的开关动作频率,从而在保持总的控制精度的同时,降低总的开关损耗.该方法只需加入一个调整电路,即可明显降低有源电力滤波器的开关损耗.用电磁暂态程序进行的计算机仿真结果表明,该方法可在控制精度和开关频率基本相同的情况下,将有源电力滤波器的开关损耗降低10%以上,而且各相开关的温升也更加平稳. 相似文献
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欧阳柏玉 《湖南师范大学自然科学学报》1995,(1)
本文考虑有局部右单位元子环的Morita-like等价,推广了1991年许永华在文[1]中建立的定理. 相似文献
9.
OuYang Shoucheng 《中国工程科学》2006,4(3):81-88
This paper is only an outline for the observed fact of twists-up of matter, super-low temperature and modern discovered appearance of thing of twists-ups of matters and irregular spin flow for electrochemistry, photochemistry in experiment, and involved problems of transform of spin flow and the process of blown-up and transformation for deformed spin flow, spin field, cold after death, heat after death, yet. The understand of spin of matter construction involved the crux of that questions are left over by contemporary science, and it has hinted new trends of science develop and revolution of systems for sense, theory and method, too. 相似文献
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1 IntroductionModern man-made systems have become more and morecomplex to achieve many automatic and intelligent tasksinstead of be executed by human beings .However ,since theprimaryrole of the systemoperationshould be human beings ,the challenge tothe operating support systemhas beenledtoa paradoxical situation. They should be complex themselvestotake charge of the complex interaction of the systemandsolve such difficult tasks such as fault diagnosis and processcontrol inone hand,and alsothe… 相似文献