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Moving horizon based wavelet de-noising method of dual-observed geomagnetic signal for nonlinear high spin projectile roll positioning

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Defence Technology（防务技术） 2020年第2期16卷 417-424页

作者： ting-ting Yin Fang-xiu Jia Xiao-ming Wang ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing210094China

Phase-frequency characte ristics of approximate sinusoidal geomagnetic signals can be used fo r projectile roll positioning and other high-precision trajectory correction *** sinusoidal geomagnetic signal deforms in the exposed and magnetically contaminated *** order to preciously recognize the roll information and effectively separate the noise component from the original geomagnetic sequence,based on the error source analysis,we propose a moving horizon based wavelet de-noising method for the dual-observed geomagnetic signal filtering where the captured rough roll frequency value provides reasonable wavelet decomposition and reconstruction level selection basis for sampled sequence;a moving horizon window guarantees real-time performance and non-cumulative calculation *** complete geomagnetic data in full ballistic range and three intercepted paragraphs are used for performance *** positioning performance of the moving horizon wavelet de-noising method is compared with the band-pass *** results show that both noise reduction techniques improve the positioning accuracy while the wavelet de-noising method is always better than the band-pass *** results suggest that the proposed moving horizon based wavelet de-noising method of the dual-observed geomagnetic signal is more applicable for various launch conditions with better positioning performance.

关键词： High-spin projectile roll positioning Dual-observed geomagnetic signal Wavelet de-noising Discrete wavelet transform

Integrable nonlocal PT-symmetric generalized so(3,R)-mKdV equations

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Communications in Theoretical Physics 2023年第12期75卷 19-24页

作者： Shou-ting Chen Wen-xiu Ma School of Mathematics and Statistics Xuzhou University of TechnologyXuzhou 221008JiangsuChina Department of Mathematics Zhejiang Normal UniversityJinhua 321004ZhejiangChina Department of Mathematics King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics and Statistics University of South FloridaTampaFL 33620-5700United States of America School of Mathematical and Statistical Sciences North-West UniversityMafikeng CampusPrivate Bag X2046Mmabatho 2735South Africa

Based on a soliton hierarchy associated with so(3,R),we construct two integrable nonlocal PT-symmetric generalized mKdV *** key step is to formulate two nonlocal reverse-spacetime similarity transformations for the involved spectral matrix,and therefore,integrable nonlocal complex and real reverse-spacetime generalized so(3,R)-mKdV equations of fifth-order are *** resulting reduced nonlocal integrable equations inherit infinitely many commuting symmetries and conservation laws.

关键词： integrable equation lax pair nonlocal reduction PT-symmetry zero curvature equation

Potential Effects of the COVID-19 Pandemic on the Developing Brain

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Neuroscience Bulletin 2023年第2期39卷 343-347页

作者： xiang Yu xiu Xu State Key Laboratory of Membrane Biology School of Life SciencesPeking-Tsinghua Center for Life Sciencesand Peking University McGovern InstitutePeking UniversityBeijing 100871China Autism Research Center of Peking University Health Science Center Beijing 100191China Chinese Institute for Brain Research Beijing 102206China Department of Child Healthcare Children’s Hospital of Fudan UniversityShanghai 201102China

By now,the COVID-19 pandemic has affected all corners of the world for over two *** years constitutes 4%of the life experience of a 50-year-old,or 50%of the life experience of a ***,in terms of the sheer proportion of... 详细信息

关键词： has she ID

Solutions for Schrodinger-Poisson system involving nonlocal term and critical exponent

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Applied Mathematics(A Journal of Chinese Universities) 2023年第3期38卷 357-372页

作者： MO xiu-ming MAO An-min WANG xiang-xiang School of Biomedicine Beijing City UniversityBeijing 100094China School of Mathematical Sciences Qufu Normal UniversityQufu 273165China.

In this paper,we consider the following Kirchhoff-Schrodinger-Poisson system:{−(a+b∫_(R^(3))|∇u|^(2))△u+u+ϕu=μQ(x)|u|^(q-2)u+K(x)|u|^(4)u,in R^(3),−△ϕ=u^(2) the nonlinear growth of|u|^(4)u reaches the Sobolev critical *** combining the variational method with the concentration-compactness principle of Lions,we establish the existence of a positive solution and a positive radial solution to this problem under some suitable *** nonlinear term includes the nonlinearity f(u)~|u|^(q-2)u for the well-studied case q∈[4,6),and the less-studied case q∈(2,3),we adopt two different strategies to handle these *** result improves and extends some related works in the literature.

关键词： variational methods critical exponent concentration-compactness principle

Coordination for a Closed-loop Supply Chain with Recycling Platform Considering Dynamic Setting

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 425-451页

作者： Zehua xiang ting Ji Lingfeng Dong School of Management Zhejiang UniversityHangzhou310058China School of Business Hangzhou City UniversityHangzhou310015China Alibaba Business College Hangzhou Normal UniversityHangzhou311121China

This paper presents a dynamic closed-loop supply chain(CLSC)model,incorporating a manufacturer,a retailer,and an internet recycling platform(IRP),utilizing differential game theory while considering the forgetting effect of *** model encompasses factors such as the quality level of used products and Big Data marketing(BDM),comparing optimal equilibriums under decentralized and cooperative decision *** effectively coordinate the dynamic CLSC at each time point,we propose a revenue-sharing and cost-sharing(RSCS)combined *** addition to ensuring reasonable sharing of revenues and costs,this contract allows the manufacturer to flexibly adjust wholesale prices for final products and transfer prices for used products in order to distribute profits appropriately and achieve Pareto optimality within the CLSC ***,our results indicate that there exists a threshold for Big Data marketing efficiency;high-efficiency BDM not only facilitates increased recycling on Internet platforms but also reduces unit recycling costs for ***,when implementing the combined contract,Big Data marketing efficiency does not impact the transfer price paid by manufacturers to Internet recycling platforms.

关键词： Big Data marketing differential game closed-loop supply chain coordination internet recycling platform

How does the host-specialized aphid deal with food deficiency？

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Insect Science 2014年第3期21卷 334-341页

作者： ting-ting Xu ting-ting Ma xiang-Dong Liu Department of Entomology Nanjing Agricultural University Nanjing China

Aphis gossypii Glover shows obvious host specialization, with cucurbit- and cotton-specialized biotypes or host races in many regions. Because its annual natal hostcrops senesce earlier the cucurbit-specialized biotype may suffer food deficiency. The method this biotype uses to overcome this challenge is still poorly understood. In orderto understand the potential of the cucurbit-specialized biotype aphids in host shift and usage, the performance of this biotype on cotton （Gossypium hirsutum）, a common butpoor quality host plant, was explored in this study. The cucurbit-specialized aphids could establish populations on cotton only when these plants had at least nine leaves, and subsequent populations developed rather slowly. The presence of whitefly populations on cotton improved the success rate of cucurbit-specialized aphids. The cucurbit-specialized aphidswere mainly distributed on the older leaves of cotton, with only a few settling on the upper leaves. The cucurbit-specialized aphids reared on cotton for 40, 54 and 61 days stillmaintained strong preference for their natal host plant, cucumber （Cucumis sativus）, rather than cotton, and their net reproductive rates and intrinsic rates of natural increase weredramatically lower when they were transferred onto new six-leaf cotton plants or detached leaves. Therefore, we concluded that the cucurbit-specialized aphids have the potentialto utilize mature or whitefly-stressed cotton plants, but that this feeding experience on cotton did not alter their specialization for cucurbits. Some cotton plants could act as atemporary host for the cucurbit-specialized aphids to overcome food deficiency arising from senescing cucurbits.

关键词： Aphidgossypii cotton-melon aphid host shift host specialization temporary host whitefly-stressed cotton

Lump solutions to a generalized Bogoyavlensky-Konopelchenko equation

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Frontiers of Mathematics in China 2018年第3期13卷 525-534页

作者： Shou-ting CHEN Wen-xiu MA School of Mathematics and Physical Science Xuzhou Institute of Technology Xuzhou 221008 China Department of Mathematics and Statistics University of South Florida Tampa FL 33620 USA College of Mathematics and Systems Science Shandong University of Science and Technology Qingdao 266590 China International Institute for Symmetry Analysis and Mathematical Modelling Department of Mathematical Sciences North-West University Mafikeng Campus Mmabatho 2735 South Africa

A （2 ＋ 1）-dimensional generalized Bogoyavlensky-Konopelchenko equation that possesses a Hirota bilinear form is considered. Starting with its Hirota bilinear form, a class of explicit lump solutions is computed through conducting symbolic computations with Maple, and a few plots of a specific presented lump solution are made to shed light on the characteristics of lumps. The result provides a new example of （2 ＋ 1）-dimensional nonlinear partial differential equations which possess lump solutions.

关键词： Symbolic computation lump solution soliton theory

Emergy analysis of paddy farming in Hunan Province, China： A new perspective on sustainable development of agriculture

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Journal of Integrative Agriculture 2016年第10期15卷 2426-2436页

作者： YI ting xiang Ping-an Biological Science and Technology College Hunan Agricultural University Changsha 410128 P.R. China Key Laboratory of Rural Ecosystem Health in Dongting Lake Area of Hunan Province Changsha 410128 P.R. China Business College of Hunan Agricultural University Changsha 410128 P.R. China

The multi-functionality of paddy farming has become a hot issue recently. Paddy farming provides numerous ecosystem services that are crucial to human well-being. However, evaluation of the contribution of paddy farming to human well-being usually focus on its economic value, while its non-market services are usually ignored. Only evaluating the market profits or market relative benefits cannot reflect comprehensively the contribution of paddy farming to people＇s well-being. This will affect people＇s choices for or against paddy farming activities and people＇s opt for invest or not invest in it. A comprehensive evaluation of paddy farming can provide an important reference for the government and society to conserve the multi-functionality of paddy farming and achieve sustainable development. To this end, this paper reports a case evaluation of paddy farming in Hunan, the largest rice producing as well as rice yield province in China, and uses emergy theory to make a comprehensive evaluation for paddy farming. The emergy evaluation results of the paddy ecosystem in Hunan are as follows： in 2010, the input emergy of the paddy ecosystem in Hunan is 2.51E＋22 sej and the output emergy is 6.31E＋22sej. For the input emergy, the part from natural resources is 1.96E＋21 sej and the part from human society is 2.32E＋22sej; for the output emergy, the part from products is 2.22E＋22 sej, the part from impositive externality is 4.16E＋22 sej and the part from negative externality is –7.41E＋20 sej. Taking the non-market outputs into consideration, the gains from the human economic society＇s 1 $ input in paddy farming, emergy sustainability index（ESI） and emergy profit rate are respectively 2.73 $, 3.53 and 151.31%. If the evaluation leave out the non-market output, the three indexes are only 0.96 $,1.24 and 30.67%. The research results show that non-market services of paddy farming contribute significantly to human well-being. Therefore, in order to protect the multi-functionality of

关键词： paddy farming emergy analysis ecosystem services Hunan Province

Histogram-kernel Error and Its Application for Bin Width Selection in Histograms

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Acta Mathematicae Applicatae Sinica 2012年第3期28卷 607-624页

作者： xiu-xiang Wang Jian-fang Zhang Department of Mathematics Graduate University of Chinese Academy of SciencesBeijing 100049China Coltege of Management Graduate University of Chinese Academy of SciencesBeijing 100190China

Histogram and kernel estimators are usually regarded as the two main classical data-based nonparametric tools to estimate the underlying density functions for some given data sets. In this paper we will integrate them and define a histogram-kernel error based on the integrated square error between histogram and binned kernel density estimator, and then exploit its asymptotic properties. 3ust as indicated in this paper, the histogram-kernel error only depends on the choice of bin width and the data for the given prior kernel densities. The asymptotic optimal bin width is derived by minimizing the mean histogram-kernel error. By comparing with Scott＇s optimal bin width formula for a histogram, a new method is proposed to construct the data-based histogram without knowledge of the underlying density function. Monte Carlo study is used to verify the usefulness of our method for different kinds of density functions and sample sizes.

关键词： Histogram binned kernel density estimator bin width histogram-kernel error integrated square error