排序方式: 共有39条查询结果,搜索用时 31 毫秒
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可拓数据挖掘研究进展 总被引:3,自引:1,他引:2
可拓学研究用形式化模型解决矛盾问题的理论与方法,可拓数据挖掘是可拓学和数据挖掘结合的产物,它探讨利用可拓学方法和数据挖掘技术,去挖掘数据库中与可拓变换有关的知识,包括可拓分类知识、传导知识等可拓知识.随着经济全球化的推进,环境的多变促使了信息和知识的更新周期缩短,创新和解决矛盾问题越来越成为各行各业的重要工作.因此,如何挖掘可拓知识就成为数据挖掘研究的重要任务.研究表明,可拓数据挖掘将具有广阔的应用前景.将介绍可拓数据挖掘的集合论基础、基本知识和目前研究的主要内容,并提出今后需要进一步探讨的问题及其发展前景. 相似文献
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Sagnac effect enhancement can improve optical gyro precision. For a certain input intensity, we suggest that the other input port of beam splitter(BS) should be fed with some quantum light to break through shot noise limit(SNL) to improve Sagnac effect without increasing radiation-pressure noise(NRP). We design a Sagnac effect quantum enhancement criterion(SQEC) to judge whether some quantum light can enhance Sagnac effect and present a Sagnac effect enhancement scheme that utilizing Fock state light and parity measurement technique to extract the output phase. The results of the theoretical analysis show that the maximum sensitivity can be reached at θ = 0, and the phase precision can break through SNL and even achieve Heisenberg limit(HL). When the Fock state average photon number n is far less than coherent state, the minimum measurable angular rate is improved with (2n+1)~(1/2) times, which can deduce shot noise and increase NRP little. 相似文献
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采用基于第一性原理密度泛函理论的平面波赝势方法,对0.5NdAlO3-0.5CaTiO3晶体进行结构优化,并对其能带结构,态密度和光学性质进行了理论计算.结构优化后晶格参数与实验数据相符合,误差小于1%;能带计算结果表明0.5NdAlO3-0.5CaTiO3为间接带隙,带隙值为0.52eV;费米面附近的能带由Nd-4f,O-2p,Nd-4p,Al-3p,Ti-4d层的电子态密度确定.同时也计算了该结构的介电函数,反射率和复折射率等光学性质. 相似文献
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A new method is employed for retrieving the profiles of trace gas number densities from satellite-based ultraviolet-visible (UV-Vis) spectra of scattered sunlight, which are recorded from the limb atmosphere over a range of tangent heights. The slant column abundances of trace gas along the lines of sight (LOSs) are obtained by differential optical absorption spectroscopy (DOAS), and the tomographic technique is applied to such column abundances to retrieve two-dimensional (2D) concentration profiles. For validation of the tomographic technique, the slant column abundances are simulated by a tested 2D NO2 profile set with latitudes from 90°S to 90°N between altitudes of 0 and 100 km, and the retrieval of number density profiles on 1-km grids is performed. The results suggest that between ±80°, the retrieved structure is almost the same as the test data. According to the comparison of the selected cross sections of the vertical profiles between retrieved and true concentrations, the NO2 number densities have been retrieved with an accuracy of 15% or better and 5% for altitudes between 25 and 40 km. The validation of the retrieved data shows good agreement between the retrieved and true profiles. 相似文献
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逆向思维是一种解决矛盾问题和创新问题的重要思维模式,但目前大部分学者只是运用自然语言对其进行定性研究.利用可拓学的形式化工具——基元和可拓变换,给出了逆向变换和逆向基元的定义,从而构造了逆向思维的形式化模型,这为将来按照一定程序,甚至利用计算机软件生成逆向思维策略解决矛盾问题和创新问题奠定了基础,对于矛盾问题和创新问题的智能化处理研究具有不可替代的意义. 相似文献
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基于可拓集的可拓分类知识获取研究 总被引:5,自引:0,他引:5
以可拓集理论为依据,给出基于可拓变换的可拓分类知识的定义,并在信息元集和评价信息元集的基础上,探讨可拓分类知识的获取方法,包括质变域知识的获取、量变域知识的获取和有关拓界的知识的获取.这是可拓数据挖掘的主要内容之一,为从数据库中获取变化的分类知识提供了新的思路. 相似文献
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可拓学的应用研究、普及与推广(综述) 总被引:8,自引:0,他引:8
可拓学研究的核心是如何通过变换处理矛盾问题.介绍了近年在计算机、设计、管理、控制、检测和中医药等领域利用可拓论和可拓方法的应用研究情况,提出今后可拓学普及与推广的方向. 相似文献