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101.
关于双边的Young不等式和一个逆定理 总被引:1,自引:0,他引:1
本文将经典的W.H.Young单边不等式扩充成为双边不等式,并证明了一条类似Takahashi的逆定理。文末举了几个简单例子,以说明双边不等式的应用。 相似文献
102.
选取张家界市为研究区域,利用多指标综合评价法构建了包含21项指标的张家界市土地资源可持续利用评价指标体系.选用模糊隶属函数、线性加权函数进行综合测算,得出2010—2013年张家界市土地资源可持续利用的评价结果.2010—2013年张家界市土地资源可持续利用水平提高较明显,2012年综合评价值达到了0.851 7,处于可持续利用阶段.结合评价结果进行分析,提出了相关建议与对策. 相似文献
103.
This paper aims to contribute to the literature on the explanatory power of behavior models with heterogeneous agents. The authors present a new nonlinear structural stock market model which is a nonlinear deterministic process buffeted by dynamic noise. An exogenous noise is introduced to the model with the assumption of IID normal innovations of the fundamental value in order to investigate how noisy dynamics interacts with deterministic process. The market is composed of two typical trader types: the rational fundamentalists and the boundedly rational traders governed by greed and fear. The interaction between noise and deterministic element determines the evolution process of the system as key parameters are changed. The authors find the model is able to generate time series that exhibit dynamical and statistical properties closely resembling those of the S&P500 index, such as volatility clustering, fat tails (leptokurtosis), autocorrelation in square and absolute return, larger amplitude, crashes and bubbles. The authors also investigate the nonlinear dependence structure in our data. The results indicate that the GARCH-type model cannot completely account for all nonlinearity in our simulated market, which is thus consistent with the results from real markets. It seems that the nonlinear structural model is more powerful to give a satisfied explanation to market behavior than the traditional stochastic approach. 相似文献
104.
1.INTRODUCTIONFuzeisaninformationprocessingsystem[1]andhassystemOPeningandcODtrollingfestures.TheopeningfeatureoffuseiseXPressedbytheinformationchangewithoutside;ThecontrollingfeatureisexpressedbytheexplosionpointcontrolandstatecODtrol.ThebasisofaChievingthecoDtrolisgainingandprocessingthetargetinfortnstioneffectively.DmereDtfromthetraditionalanalyzingmethods,thispaperresearchesthechannelfeatureofgannnginformationoffUzeandcharacteristicsofhighfrequencysignalprocessingOfradpromtyfuzem… 相似文献
105.
Sonar images have complex background, low contrast, and deteriorative edges; these characteristics make it difficult for researchers to dispose the sonar objects. The multi-resolution analysis represents the signals in different scales efficiently, which is widely used in image processing. Wavelets are successful in disposing point discontinuities in one dimension, but not in two dimensions. The finite Ridgelet transform (FRIT) deals efficiently with the singularity in high dimension. It presents three improved denoising approaches, which are based on FRIT and used in the sonar image disposal technique. By experiment and comparison with traditional methods, these approaches not only suppress the artifacts, but also obtain good effect in edge keeping and SNR of the sonar image denoising. 相似文献
106.
通过定义n维空间的单位阶跃函数和Fourier变换,分析了单位阶跃函数对存在广义Fourier变换的可分离变量的函数(信号)的屏蔽效应,利用卷积定理和Dirichlet积分证明了所给出的定理. 相似文献
107.
108.
波形整形器是实现分离式霍普金森压杆(SHPB)实验恒应变率加载的重要手段之一,为研究整形器对入射波形的影响规律,本文以紫铜、黄铜、铝等软材料为研究对象,在37 mm霍普金森压杆(SHPB)设备上开展了整形器直径和厚度、撞击杆速度、长度等因素对入射波形状影响规律的实验研究,并结合数值模拟仿真研究与量纲分析,给出了入射波T1和T2拐点的量纲一应力、量纲一时间的定量表达式,T1拐点的量纲一应力σ/σ*与量纲一参数Y/σ*,(d/Db)2和h/Lb分别呈线性关系;T2拐点的量纲一时间t/t*与量纲一参数h/Lb、Y/σ*都是呈线性关系的. 相似文献
109.
在N,N-二甲基甲酰胺(DMF)催化下,用氯化亚砜氯代1-苯基-5-(4-甲基苯基)-1H-3-羟基吡唑(1a),以83%的高产率获得了4-氯-1-苯基-5-(4-甲基苯基)-1H-3-羟基吡唑(2a),用高效液相色谱(HPLC)跟踪反应,得出最佳反应条件为:n(1a)∶n(DMF)=10∶1,在SOCl2中回流4 h,并分离得到单质硫,提出了DMF催化的吡唑亲电/亲核氯代机制。通过合成系列吡唑底物1b~1h,研究了氯代机制的普适性,其氯代产物2b~2h经核磁共振氢谱(1H NMR)、核磁共振碳谱(13C NMR)和元素分析表征,并用X线衍射法测定了2d的晶体结构。该氯代反应操作简单、官能团相容性好。 相似文献
110.
Review of the fabrication and application of porous materials from silicon-rich industrial solid waste 下载免费PDF全文
Chao Miao Lixing Liang Fan Zhang Shumei Chen Kaixuan Shang Jinlong Jiang Yi Zhang Jing Ouyang 《矿物冶金与材料学报》2022,29(3):424-438
Porous materials have promise as sound insulation, heat barrier, vibration attenuation, and catalysts. Most industrial solid wastes, such as tailings, coal gangue, and fly ash are rich in silicon. Additionally, a high silicon content waste is a potential raw material for the syn- thesis of silicon-based, multi-porous materials such as zeolites, mesoporous silica, glass-ceramics, and geopolymer foams. Representative sil- icon-rich industrial solid wastes (SRISWs) are the focus of this mini review of the processing and application of porous silicon materials with respect to the physical and chemical properties of the SRISW. The transformation methods of preparing porous materials from SRISWs are summarized, and their research status in micro-, meso-, and macro-scale porous materials are described. Possible problems in the application of SRISWs and in the preparation of functional porous materials are analyzed, and their development prospects are discussed. This review should provide a typical reference for the recycling and use of industrial solid wastes to develop sustainable “green materials.” 相似文献