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An Affirmative Result of the Open Question on Determining Function Jumps by Spline Wavelets

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Acta Mathematica Sinica,English Series 2018年第5期34卷 921-932页

作者： Hai Ying ZHANG Xian Liang SHI jian zhong wang Science of College Hangzhou Dianzi University Hangzhou 310018 P. R. China College of Mathematics and Computer Science Hu'nan Normal University Changsha 410081 P. R. China Department of Mathematics and Statistics Sam Houston State University Huntsville TX 77341 USA

We study the open question on determination of jumps for functions raised by Shi and Hu in 2009. An affirmative answer is given for the case that spline-wavelet series are used to approximate the functions.

关键词： Jump B-spline wavelets

A new C_(27)-steroidal glycoside from Ophiopogon japonicus

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Chinese Chemical Letters 2008年第1期19卷 82-84页

作者： jian zhong wang Li Ming Ye Xiao Bing Chen West China College of Pharmacy Sichuan University Chengdu 610041 China

A new C27-steroidal glycoside with three known compounds were isolated from the tuber of Ophiopogonjaponicus （Thunb.） Ker-Gawl. Based on the spectral analysis, including HRMS, 1H NMR, 13C NMR, DEPT, 1H-1H COSY, HMQC and HMBC, their chemical structures were determined as pennogenin-3-O-α-L-rhamnopyranosyl-（1→ 2）-β-D-xylopyranosyl-（1→ 4）-13-D-gluco- pyranoside （1）, pennogenin-3-O-α-L-rhamnopyranosyl-（1→ 2）-β-D-glucopyranoside （2）, ophiopojaponin C （3） and ophiopogonin D （4）. 2007 jian zhong wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Ophiopogon japonicus C27-steroidal glycoside

Modeling sintering behavior of metal fibers with different fiber angles

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Rare Metals 2018年第10期37卷 886-893页

作者： Dong-Dong Chen Zhou-Shun Zheng jian-zhong wang Hui-Ping Tang School of Mathematics and Statistics Central South University State Key Laboratory of Porous Metal Materials Northwest Institute for Nonferrous Metal Research

The formation of sintering necks between two metal fibers was investigated using the oval-oval model with respect to the fiber angle range of 0°-90°. Surface diffusion was assumed to be the predominant mechanism in every section of the junction of two metal fibers in this model, which was addressed numerically using the level- set method. The growth rates of the sintering necks in the direction of the bisector of obtuse angle, the bisector of acute angle and the fiber axis were discussed in detail. It is found that the growth rate of the sintering necks decreases with fiber angle increasing in the direction of the fiber axis and the bisector of acute angle. However, an opposite variation in growth rate of sintering necks can be found in the direction of the bisector of obtuse angle. The numerical simulation results show that the growth rate of the sintering necks is significantly affected by the initial local geomet- rical structure which is determined by the fiber angle.

关键词： Metal fiber Surface diffusion Fiber angle Initial local geometrical structure Initial evolution speed

Experimental study of transient pressure wave in the behind armor blunt trauma induced by different rifle bullets

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Defence Technology（防务技术） 2020年第4期16卷 900-909页

作者： Rui-guo Han Yong-jie Qu Wen-min Yan Bin Qin Shu wang jian-zhong wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China Science and Technology on Transient Impact Laboratory Beijing102202PR China

Pressure wave plays an important role in the occurrence of behind armor blunt trauma(BABT),and ballistic gelatin is widely used as a surrogate of biological tissue in the research of *** of pressure wave in the gelatin behind armor for different rifle bullets is *** aim of this study was to observe dynamic changes in pressure wave induced by ballistic blunt impact on the armored gelatin block and to compare the effects of bullet type on the parameters of the transient pressure *** gelatin blocks protected with National Institute of Justice(NIJ) class III bulletproof armor were shot by three types of rifle bullet with the same level of impact *** transient pressure signals at five locations were recorded with pressure sensors and three parameters(maximum pressure,maximum pressure impulse,and the duration of the first positive phase) were determined and *** results indicated that the waveform and the twin peak of transient pressure wave were not related to the bullet ***,the values of pressure wave's parameters were significantly affected by bullet ***,the attenuation of pressure amplitude followed the similar law for the three *** findings may be helpful to get some insight in the BABT and improve the structure design of bullet.

关键词： Behind armor blunt trauma Ballistic gelatin Pressure wave Body armor

Improvement on Conventional Load Distribution Algorithm in Hot Tandem Mills

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Journal of Iron and Steel Research International 2007年第2期14卷 36-41页

作者： LIHai-jun XU jian-zhong wang Guo-dong LIU Xiang-hua State Key Laboratory of Rolling Teehnology and Automation Northeastern University Shenyang 110004 Liaoning China

Load distribution is a key technology in strip hot rolling process, which influences the coil＇s mierostrueture and performance. Currently, Newton-Raphson algorithm is applied to load distribution of hot tandem mills in many hot rolling plants and has some serious defects such as having a strict restriction on initial iterative calculation value and requiring coefficient matrix of nonlinear equations to be nonsingular. To eliminate these defects and improve the online performance of the process control computer, Newton descendent numeric algorithm is introduced to this field to widen the initial value range and a new model named error conversion algorithm is put forth to deal with special conditions when the coefficient matrix is singular. Furthermore, considering the characteristics of load distribution, a condition of strip thickness distribution abnormality and corresponding solutions are provided which ensure that rolling parameters can be calculated normally. Simulation results show that the improved algorithm has overcome the defects of the Newton-Raphson algorithm and is suitable for online application.

关键词： load distribution hot tandem mill process control computer Newton-Raphson algorithm

Hardware design of a localization system for staff in high-risk manufacturing areas

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第1期14卷 1-10页

作者： Rui-rong wang Rong-rong YE Cui-fei XU jian-zhong wang An-ke XUE Institute of Information and Control Hangzhou Dianzi University

In this paper, we propose a hardware design for an effective real time indoor localization system for staff working in high-risk manufacturing areas. Because of the special requirements of our system, the chirp spread spectrum （CSS） is the most suitable indoor localization technology. The details of the new localization system are described. The system involves several anchors, tags, and a gateway, all of which use the nanoLOC TRX transceiver （NASTR1） RF chip （Nanotron Co., Germany）, which is based on the CSS technology. To validate the effectiveness of our system, both ranging and localization tests were carried out. The difference between the ranging accuracy indoors and outdoors was small. The localization system can position indoor mobile staffprecisely, enabling the establishment of an emergency rescue mechanism.

关键词： Wireless indoor localization High-risk manufacturing area Chirp spread spectrum (CSS) NanoLOC TRXtransceiver (NA5 TR 1 )

Effect of electric pulse modification on mircostructure and properties of Ni-rich Al-Si piston alloy

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China Foundry 2016年第2期13卷 139-142页

作者： Bing wang Jia-yi wang Li-dan Tang Jin-gang Qi jian-zhong wang Department of Materials Liaoning University of Technology

In order to improve the properties of Ni-rich(2.5wt.%) Al-Si piston alloy, electric pulse modification was applied in fabricating the Ni-rich Al-Si piston alloy in this study. The effect of electric pulse modification on the mechanical properties of the Ni-rich Al-Si piston alloy was studied using optical microscope(OM), scanning electron microscope(SEM), X-ray diffraction(XRD), microhardness measurement and tensile strength *** results showed that the microstructures of Ni-rich Al-Si piston alloy treated by electric pulse modification were refined, the solid solubility of Cu, Ni, Si, etc. in α-Al matrix was improved, and furthermore, the microhardness and high-temperature tensile strength were increased by 9.41% and 17.5%, respectively. The distribution of second phases was also more uniform compared with that of a non-modified sample.

关键词： Al-Si piston phase structure microhardness

Graphite-polypyrrole coated 316L stainless steel as bipolar plates for proton exchange membrane fuel cells

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 53-58页

作者： Li-jun Yang Hai-jun Yu Li-jun jiang Lei Zhu Xu-yu jian zhong wang Energy Materials and Technology Research Institute Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

316L stainless steel（SS 316L） is quite attractive as bipolar plates in proton exchange membrane fuel cells（PEMFC）.In this study,graphite-polypyrrole was coated on SS 316L by the method of cyclic *** surface morphology and chemical composition of the graphite-polypyrrole composite coating were investigated by scanning electron microscopy（SEM） and X-ray photoelectron spectroscopy（XPS）.A simulated working environment of PEMFC was applied for testing the corrosion properties of graphite-polypyrrole coated SS *** current densities in the simulated PEMFC anode and cathode conditions are around 3×10-9 and 9×10-5 A·cm-2,*** addition,the interfacial contact resistance（ICR） was also *** ICR value of graphite-polypyrrole coated SS 316L is much lower than that of bare SS ***,graphite-polypyrrole coated SS 316L indicates a great potential for the application in PEMFC.

关键词： proton exchange membrane fuel cells polypyrrole graphite corrosion contact resistance stainless steel

CHEMISTRY OF DENUDATINE.I.A NOVEL REARRANGEMENT OF DENUDATINE

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Chinese Chemical Letters 1991年第5期2卷 361-362页

作者： Feng Peng wang jian zhong wang Rong ZHANG Department of Chemistry of Medicinal Natural Products College of PharmacyWest China University of Medical SciencesChengdu610041

Treatment of denudatine 1 with 10% HCl soln. at 45-50℃ for 3 days leads to a pair of epimers 4A and 4B, Structures of 4A and 4B have been elucidated on the basis of chemical and spectral methods.

关键词： wang CHO A NOVEL REARRANGEMENT OF DENUDATINE CHEMISTRY OF DENUDATINE CDC Book