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Finding Chaos in Finnish GDP

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International Journal of Automation and computing 2014年第3期11卷 231-240页

作者： Radko Kíz Faculty of Electrical Engineering Czech Technical University

The goal of this paper is to analyze the Finnish gross domestic product(GDP) and to find chaos in the Finnish GDP. We chose Finland where data has been available since 1975, because we needed the longest time series possible. At first we estimated the time delay and the embedding dimension, which is needed for the Lyapunov exponent estimation and for the phase space ***, we computed the largest Lyapunov exponent, which is one of the important indicators of chaos. Then we calculated the 0-1 test for chaos. Finally we computed the Hurst exponent by rescaled range analysis and by dispersional analysis. The Hurst exponent is a numerical estimate of the predictability of a time series. In the end, we executed a recurrent analysis and displayed recurrence plots of detrended GDP time series. The results indicated that chaotic behaviors obviously exist in GDP.

关键词： Chaos theory gross domestic product(GDP) time series analysis phase space reconstruction Hurst exponent largest Lyapunov exponent recurrent analysis.

Dynamic Deformation of Frozen Soil at a High Strain Rate:Experiments and Damage-Coupled Constitutive Model

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Acta Mechanica Solida Sinica 2021年第6期34卷 895-910页

作者： z.W.zhu W.R.Tang G.z.Kang Applied Mechanics and Structural Safety Key Laboratory of Sichuan Province School of Mechanics and EngineeringSouthwest Jiaotong UniversityChengdu610036China Northwest institute of Eco-Environment and Resources State Key Laboratory of Frozen Soil EngineeringChinese Academy of SciencesLanzhou730000China

The dynamic compressive deformation of frozen soil was investigated by conducting the split-Hopkinson pressure bar(SHPB)experiments at three temperatures and different high strain rates,and the dynamic stress–strain responses and failure modes of the frozen soil were *** experimental results demonstrate that the frozen soil exhibits evident dependence on the strain rate and temperature under the dynamic loading *** dynamic compressive stress–strain curve of the frozen soil was divided into three parts:the linear,nonlinear rising,and strain softening *** nonlinear rising and strain softening parts were both caused by the damage attributed to the debonding between the ice particles and soil matrix,from which a rate-dependent damage evolution equation was ***,a damage-coupled dynamic viscoelastic constitutive model of frozen soil at high strain rate was derived.A comparison between the theoretically predicted results and the experimental ones showed that the developed dynamic viscoelastic model could well describe the dynamic mechanical behavior of frozen soil at high strain rate.

关键词： Frozen soil Dynamic compression High strain rate Damage Constitutive model

Influence of Non-Uniform Temperature Distribution on Metallic Charge Length on Energy and Force Parameters During Groove-Rolling

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Journal of Iron and Steel Research International 2012年第8期19卷 17-24页

作者： Mróz Sebastian Czestochowa University of Technology

Change in the temperature of band over its length, associated with the stock being non-uniformly heated in the furnace, influences the variations in the magnitudes of energy-force parameters. Using the FEM (Finite Element Model) programs for the computation of the values of the energy-force parameters can take into account the distribution of temperature over the band length. The mathematical model of the computer program Forge2008 was used to theoretically examine the energy-force parameters and plastic metal flow in the roughing stands of the continuous rolling mill. The results of experimental investigation of influence of the non-uniform temperature distribution were presented on the metallic charge length on the energy and force parameters and dimensions of the band during round bars rolling. Thermovision monitoring energy and force parameters monitoring were carried out in continuous rolling mill D350 in one of the Polish industrial plants. On the basis of obtained results, it could be stated that non-uniform distribution of temperatures along the charge length causes local increase of energy and force parameters values and also such distribution affects the local increase of the width of rolled band. The rolling process of charge with non-uniform distribution of temperature could lead to exceeding required dimensional tolerances of the final products.

关键词： groove-rolling energy parameter force parameter numerical technique FEM

CARLESON MEASURES AND THE FRACTIONAL DERIVATIVES OF HOLOMORPHIC FUNCTIONS IN THE UNIT BALL OF ￠

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Chinese Annals of Mathematics,Series B 1998年第3期19卷 299-304页

作者： Hu z. Department of Mathematics Huzhou Teachers College Huzhou 313000 China

§１．ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅＣａｒｌｅｓｏｎｍｅａｓｕｒｅｉｎｔｈｅｕｎｉｔｄｉｓｋｏｆｔｈｅｃｏｍｐｌｅｘｐｌａｎｅＣ｜ｗａｓｆｉｒｓｔｉｎｔｒｏｄｕｃｅｄｂｙＣａｒｌｅｓｏｎｉｎｔｈｅｓｔｕｄｙｏｆｉｎ... 详细信息

§１．ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅＣａｒｌｅｓｏｎｍｅａｓｕｒｅｉｎｔｈｅｕｎｉｔｄｉｓｋｏｆｔｈｅｃｏｍｐｌｅｘｐｌａｎｅＣ｜ｗａｓｆｉｒｓｔｉｎｔｒｏｄｕｃｅｄｂｙＣａｒｌｅｓｏｎｉｎｔｈｅｓｔｕｄｙｏｆｉｎｔｅｒｐｏｌａｔｉｏｎｐｒｏｂｌｅ...

关键词：积分不等式分解导出数全纯函数卡里森测度

Triebel-Lizorkin space boundedness of Marcinkiewicz integrals associated to surfaces

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Applied Mathematics(A Journal of Chinese Universities) 2015年第4期30卷 418-446页

作者： YABUTA Kz Research Center for Mathematical Sciences Kwansei Gakuin University

In the present paper, we consider the boundedness of Marcinkiewicz integral operator μΩ,h,Ф along a surface Г = {x = Ф（｜y｜）y/｜y｜）} on the Triebel-Lizorkin space Fq,q^α（R^n ） for Ω belonging to H1 （Sn-1） and some class WFα（S^n-1）, which relates to Grafakos-Stefanov class. Some previous results are extended and improved.

关键词： Marcinkiewicz integral Littlewood-Paley operator Triebel-Lizorkin space rough kernel.

A Simplified Regular Solution Model for Solubility of Nonmetal (2) in Metal(1)-Metal(3) Alloy Systems

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Journal of Materials Science & Technology 1996年第4期12卷 281-285页

作者： Fang, z zhang, QR CHANGSHA TECH COLL DEPT METCHANGSHA 410012PEOPLES R CHINA

A simplified regular solution model for the solubility of nonmetallic element (2) in metal(1)-metal(3) alloy system has been derived and applied to the Fe-C-j, Ni-S-j and Fe-N-j (j denotes a metal) systems with satisf... 详细信息

关键词： Alloys

Current status and future directions of high-throughput ADME screening in drug discovery

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Journal of Pharmaceutical Analysis 2020年第3期10卷 201-208页

作者： Wilson z.Shou Bristol-Myers Squibb PO Box 4000PrincetonNJ08540USA

During the last decade high-throughput in vitro absorption,distribution,metabolism and excretion(HTADME)screening has become an essential part of any drug discovery effort of synthetic *** conduct of HT-ADME screening has been"industrialized"due to the extensive development of software and automation tools in cell culture,assay incubation,sample analysis and data *** HT-ADME assay portfolio continues to expand in emerging areas such as drug-transporter interactions,early soft spot identification,and ADME screening of peptide drug ***,thanks to the very large and high-quality HT-ADME data sets available in many biopharma companies,in silico prediction of ADME properties using machine learning has also gained much momentum in recent *** this review,we discuss the current state-of-the-art practices in HT-ADME screening including assay portfolio,assay automation,sample analysis,data processing,and prediction model *** addition,we also offer perspectives in future development of this exciting field.

关键词： In vitro HT-ADME Automation Bioanalysis Mass spectrometry Acoustic ejection mass spectrometry

Pinless Friction Stir Spot Welding of Mg-3Al-1zn Alloy with zn Interlayer

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Journal of Materials Science & Technology 2016年第1期32卷 76-88页

作者： R.z.Xu D.R.Ni Q.Yang C.z.Liu z.Y.Ma College of Materials Science and Engineering Shenyang Aerospace University Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

With the addition of a thin zn interlayer, 2.4 mm thick Mg-3AI-1zn alloy sheets were friction stir spot welded （FSSW） using a pinless tool with fiat, convex and concave shoulder shapes. The results showed that an alloying reaction took place between the Mg substrate and zn interlayer during FSSW, forming a discontinuous intermetallics layer composed of dispersive （α-Mg ＋ Mgzn） eutectic structure under- neath the shoulder and a Mg-zn intermetallics bonding zone at the outside of the joints. This alloying reaction increased the bonded area and eliminated the hook defects, thereby producing sound FSSWjoints with a shallow keyhole without hook defects. The increase of plunge depth was beneficial to the Mg-zn diffusion, thereby increasing the tensile-shear load of the joints. However, excessive plunge depths re- sulted in a decrease of the effective sheet thickness, reducing the strength of the joints. At a small plunge depth, the convex and concave shoulders were more beneficial to the interface reaction than the fiat shoul- der. The maximum joint load of 6.6 kN was achieved by using the concave shoulder at a plunge depth of 1.0 mm. A post-welding heat treatment promoted the dissolution of the discontinuous reaction layer in the joints; however, it led to the occurrence of void defects, influencing the bonding strength.

关键词： Friction stir spot welding Magnesium alloys zn interlayer Hook defects

高浓度4NQO建立小鼠舌癌动物模型的改进方法

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武汉大学学报（医学版） 2024年第5期45卷 533-537页

作者：艾克拜尔·托乎提林泽华蔡捷陈雄武汉大学中南医院耳鼻咽喉头颈外科湖北武汉430071

目的:利用含高浓度4-硝基喹啉-1-氧化物(4NQO)的水与固体饲料相结合方式,旨在探讨短时间构建高生存率舌癌小鼠模型的方法。方法:将12只BALB/c小鼠随机分为对照组(H2O,n=4)、中剂量实验组(250μg/mL 4NQO,n=4)和高剂量实验组(300μg/mL 4... 详细信息

目的:利用含高浓度4-硝基喹啉-1-氧化物(4NQO)的水与固体饲料相结合方式,旨在探讨短时间构建高生存率舌癌小鼠模型的方法。方法:将12只BALB/c小鼠随机分为对照组(H2O,n=4)、中剂量实验组(250μg/mL 4NQO,n=4)和高剂量实验组(300μg/mL 4NQO,n=4),固液交替喂养,对小鼠的外貌、体质量和舌黏膜状态进行观察并记录,12周后处死小鼠,取材进行HE染色。结果:研究发现中剂量组的小鼠均造模成功,其中3只小鼠的舌黏膜出现乳头状样新生物,并且HE染色发现癌巢及角化珠的病理特征,余1只小鼠舌黏膜仅出现白斑样改变,病理表现为舌黏膜上皮重度异型增生。而高剂量组中的小鼠在造模过程中全部死亡。结论:250μg/mL 4NQO能在12周内成功诱导出舌癌小鼠模型,并能保证较高的生存率。

关键词：舌癌动物模型 4-硝基喹啉-1-氧化物