检索结果-南通市图书馆

Chinese Physics B 2024年第9期33卷 268-280页

作者： Luyao Zhang Xiyang xie Department of Mathematics and Physics Hebei Key Laboratory of Physics and Energy TechnologyNorth China Electric Power UniversityBaoding 071003China

We study the dynamics of fundamental and double-pole breathers and solitons for the focusing and defocusing nonlinearSchr¨odinger equation with the sextic operator under non-zero boundary conditions. Our analysis mainly focuses onthe dynamical properties of simple- and double-pole solutions. Firstly, through verification, we find that solutions undernon-zero boundary conditions can be transformed into solutions under zero boundary conditions, whether in simple-pole ordouble-pole cases. For the focusing case, in the investigation of simple-pole solutions, temporal periodic breather and thespatial-temporal periodic breather are obtained by modulating parameters. Additionally, in the case of multi-pole solitons,we analyze parallel-state solitons, bound-state solitons, and intersecting solitons, providing a brief analysis of their *** the double-pole case, we observe that the two solitons undergo two interactions, resulting in a distinctive “triangle”crest. Furthermore, for the defocusing case, we briefly consider two situations of simple-pole solutions, obtaining one andtwo dark solitons.

关键词： double-pole solitons double-pole breathers Riemann–Hilbert problem non-zero boundary conditions nonlinear Schr¨odinger equation with sextic operator

Visible-Light-Promoted Palladium-Catalyzed Cross-Coupling of lodocarboranes with Disulfides and Phenylselenyl Chloride

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第2期42卷 129-134页

作者： Shimeng Li Yizhen Liu Zuowei xie Shenzhen Grubbs Institute and Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdong 518055China

This work describes a general method for the synthesis of a series of sulfenylated and selenylated carboranes at room temperature using readily available iodocarboranes as starting materials via boron-centered carboranyl *** hypervalent boron radicals are generated by a visible-light-promoted Pd(O)/Pd(I)*** are useful intermediates and can be trapped by disulfides and phenylselenyl chloride for the convenient construction of B-S/Sebonds.

关键词： Carborane Sulfenylation Selenylation B-I activation Radical Photocatalysis Boron Selectivity

Observer design and interval estimation of time-delay discrete-time linear systems with external disturbance and measurement noise

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Control Theory and Technology 2024年第1期22卷 69-80页

作者： Junqi Yang Jianhao xie Feiyang Liu School of Electrical Engineering and Automation Henan Key Laboratory of Intelligent Detection and Control of Coal Mine EquipmentHenan Polytechnic UniversityJiaozuo454003HenanChina

For a class of time-delay discrete-time linear systems with external disturbance and measurement noise, the interval estimation problems of state and measurement noise are investigated in this paper. First, the system state together with the time-delay term and measurement noise is augmented as a new state, and a singular system is then constructed. Subsequently, a kind of decoupling technique is employed to eliminate the effect of external disturbance, and an observer is designed to simultaneously estimate the system state and measurement noise. Based on the estimated state and measurement noise, the interval estimations of system state and measurement noise are obtained by reachability analysis technique. Finally, the effectiveness of the proposed method is verified by a four-tank liquid level system.

关键词： Interval estimation Time-delay system Observer design Reachability analysis

Spatio-temporal variability of surface chlorophyll a in the Yellow Sea and the East China Sea based on reconstructions of satellite data of 2.01-2.2.

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2024年第2期42卷 390-407页

作者： Weichen xie Tao WANG Wensheng JIANG Key Laboratory of Marine Environment and Ecology Ocean University of ChinaQingdao 266100China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China

Chlorophyll-a(Chl-a)concentration is a primary indicator for marine environmental *** spatio-temporal variations of sea surface Chl-a concentration in the Yellow Sea(YS)and the East China Sea(ECS)in 2.01-2.2. were investigated by reconstructing the MODIS Level 3 products with the data interpolation empirical orthogonal function(DINEOF)*** reconstructed results by interpolating the combined MODIS daily+8-day datasets were found better than those merely by interpolating daily or 8-day ***-a concentration in the YS and the ECS reached its maximum in spring,with blooms occurring,decreased in summer and autumn,and increased in late autumn and early *** performing empirical orthogonal function(EOF)decomposition of the reconstructed data fields and correlation analysis with several potential environmental factors,we found that the sea surface temperature(SST)plays a significant role in the seasonal variation of Chl a,especially during spring and *** increase of SST in spring and the upper-layer nutrients mixed up during the last winter might favor the occurrence of spring *** high sea surface temperature(SST)throughout the summer would strengthen the vertical stratification and prevent nutrients supply from deep water,resulting in low surface Chl-a *** sea surface Chl-a concentration in the YS was found decreased significantly from 2.12.to 2.2.,which was possibly related to the Pacific Decadal Oscillation(PDO).

关键词： chlorophyll a(Chl a) data interpolation empirical orthogonal function(DINEOF) empirical orthogonal function(EOF)analysis Yellow Sea East China Sea

Mega-Constellations Based TT&C Resource Sharing: Keep Reliable Aeronautical Communication in an Emergency

在线全文

学校读者我要写书评

暂无评论

China Communications 2024年第2期21卷 1-16页

作者： Haoran xie Yafeng Zhan Jianhua Lu Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

With the development of the transportation industry, the effective guidance of aircraft in an emergency to prevent catastrophic accidents remains one of the top safety concerns. Undoubtedly, operational status data of the aircraft play an important role in the judgment and command of the Operational Control Center(OCC). However, how to transmit various operational status data from abnormal aircraft back to the OCC in an emergency is still an open problem. In this paper, we propose a novel Telemetry, Tracking,and Command(TT&C) architecture named Collaborative TT&C(CoTT&C) based on mega-constellation to solve such a problem. CoTT&C allows each satellite to help the abnormal aircraft by sharing TT&C resources when needed, realizing real-time and reliable aeronautical communication in an emergency. Specifically, we design a dynamic resource sharing mechanism for CoTT&C and model the mechanism as a single-leader-multi-follower Stackelberg game. Further, we give an unique Nash Equilibrium(NE) of the game as a closed form. Simulation results demonstrate that the proposed resource sharing mechanism is effective, incentive compatible, fair, and reciprocal. We hope that our findings can shed some light for future research on aeronautical communications in an emergency.

关键词： aeronautical emergency communication mega-constellation networked TT&C resource allocation stackelberg game

NONMONOTONE LOCAL MINIMAX METHODS FOR FINDING MULTIPLE SADDLE POINTS

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2024年第3期42卷 851-884页

作者： Wei Liu Ziqing xie Wenfan Yi South China Research Center for Applied Mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou 510631China Key Laboratory of Computing and Stochastic Mathematics(Ministry of Education) Hunan Normal UniversityChangshaHunan 410081China Hunan Provincial Key Laboratory of Intelligent Information Processing and Applied Mathematics School of MathematicsHunan UniversityChangshaHunan 410082China

In this paper,by designing a normalized nonmonotone search strategy with the BarzilaiBorwein-type step-size,a novel local minimax method(LMM),which is a globally convergent iterative method,is proposed and analyzed to find multiple(unstable)saddle points of nonconvex functionals in Hilbert *** to traditional LMMs with monotone search strategies,this approach,which does not require strict decrease of the objective functional value at each iterative step,is observed to converge faster with less ***,based on a normalized iterative scheme coupled with a local peak selection that pulls the iterative point back onto the solution submanifold,by generalizing the Zhang-Hager(ZH)search strategy in the optimization theory to the LMM framework,a kind of normalized ZH-type nonmonotone step-size search strategy is introduced,and then a novel nonmonotone LMM is *** feasibility and global convergence results are rigorously carried out under the relaxation of the monotonicity for the functional at the iterative ***,in order to speed up the convergence of the nonmonotone LMM,a globally convergent Barzilai-Borwein-type LMM(GBBLMM)is presented by explicitly constructing the Barzilai-Borwein-type step-size as a trial step-size of the normalized ZH-type nonmonotone step-size search strategy in each ***,the GBBLMM algorithm is implemented to find multiple unstable solutions of two classes of semilinear elliptic boundary value problems with variational structures:one is the semilinear elliptic equations with the homogeneous Dirichlet boundary condition and another is the linear elliptic equations with semilinear Neumann boundary *** numerical results indicate that our approach is very effective and speeds up the LMMs significantly.

关键词： Multiple saddle points Local minimax method Barzilai-Borwein gradient method Normalized nonmonotone search strategy Global convergence

Why Are Arctic Sea Ice Concentration in September and Its Interannual Variability Well Predicted over the Barents–East Siberian Seas by CFSv2.

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Meteorological Research 2024年第1期38卷 53-68页

作者： Yifan xie Ke FAN Hongqing YANG School of Atmospheric Sciences Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082

To further understand the prediction skill for the interannual variability of the sea ice concentration(SIC)in specific regions of the Arctic,this paper evaluates the NCEP Climate Forecast System version 2.CFSv2.,in predicting the autumn SIC and its interannual variability over the Barents–East Siberian Seas(BES).It is found that CFSv2.presents much better prediction skill for the September SIC over BES than the Arctic as a whole at 1–6-month leads,and high prediction skill for the interannual variability of the SIC over BES is displayed at 1–2.month leads after removing the linear ***2.can reasonably reproduce the relationship between the SIC over BES in September and such factors as the surface air temperature(SAT),2.0-hPa geopotential height,sea surface temperature(SST),and North Atlantic *** addition,it is found that the prescribed SIC initial condition in August as an input to CFSv2.is also ***,the above atmospheric and oceanic factors,as well as an accurate initial condition of SIC,all contribute to a high prediction skill for SIC over BES in *** on a statistical prediction method,the contributions from individual predictability sources are further *** high prediction skill of CFSv2.for the interannual variability of SIC over BES is largely attributable to its accurate predictions of the SAT and SST,as well as a better initial condition of SIC.

关键词： sea ice concentration the Barents-East Siberian Seas Climate Forecast System version 2.CFSv2. prediction skill predictability source atmospheric and oceanic factors initial condition

富氢液激活自噬减轻带状疱疹后神经痛大鼠痛敏并降低炎症因子的水平

在线全文

学校读者我要写书评

暂无评论

细胞与分子免疫学杂志 2017年第2期33卷 155-158,163页

作者：马洪涛陈红光董艾莉王妍妍边映雪谢克亮中国航天科工集团七三一医院麻醉科北京100074 天津医科大学总医院麻醉科天津300052

目的探讨自噬在富氢液治疗带状疱疹后神经痛(PHN)中的作用。方法雄性SD大鼠100只,采用随机数字表法,将其分为5组(n=2.):对照组、PHN组、富氢液处理的PHN组(PHN-H2.)、富氢液和3-MA同时处理的PHN组(PHN-H2.3-MA组)、富氢液和雷帕霉素(R... 详细信息

目的探讨自噬在富氢液治疗带状疱疹后神经痛(PHN)中的作用。方法雄性SD大鼠100只,采用随机数字表法,将其分为5组(n=2.):对照组、PHN组、富氢液处理的PHN组(PHN-H2.)、富氢液和3-MA同时处理的PHN组(PHN-H2.3-MA组)、富氢液和雷帕霉素(Rap)同时处理的PHN组(PHN-H2.Rap组)。通过水痘带状疱疹病毒(VZV)接种建立PHN大鼠模型。造模成功的大鼠给予腹腔注射15 mg/kg 3-MA或10 mg/kg Rap,隔日1次,连续3次。富氢液处理方式为于造模后每天2.,腹腔注射富氢液10 m L/kg,连续7 d。50只大鼠分别于造模后3、7、14、2. d,测定机械缩足反应阈(PWT);另50只大鼠,于造模后7 d,收集脊椎腰膨大处,ELISA测定肿瘤坏死因子α(TNF-α)、白细胞介素1β(IL-1β)和IL-6的含量,Western blot法测定自噬蛋白微管相关蛋白1轻链3、beclin 1、P62.水平。结果与对照组比较,PHN组大鼠PWT值减少,TNF-α、IL-1β、IL-6、LC3Ⅱ和beclin 1水平增加,P62.量减少;与PHN组比较,PHN-H2.和PHN-H2.Rap组大鼠PWT值增加,TNF-α、IL-1β和IL-6水平降低,LC3和beclin 1表达进一步增加,P62.量增加;与PHN-H2.比较,PHN-H2.3-MA组大鼠PWT值明显减少,TNF-α、IL-1β、IL-6水平增加、LC3和beclin 1水平降低、P62.量增加。结论富氢液可以通过激活自噬减轻PHN大鼠的机械痛敏和炎症因子的释放。

关键词：带状疱疹后神经痛富氢液自噬炎症因子

One more step to realistic CO_(2. reduction reactions——geometric structures evolutions at gas-solid interface

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第2期43卷 849-852页

作者： Ya-Qiang xie Xin Yu Ting Wang College of the Environment and Ecology Xiamen UniversityXiamen361102China

A rational design of copper(Cu)nanocatalyst is critical to the efficient carbon dioxide(CO_(2.)conversion toward C1/C2.chemical ***,the lack of actual information on the vicinal Cu interfaces hinders the intrinsic activitystructure correlation *** with atomic-scale in situ characterizations(AP-STM and synchrotron-based AP-XPS),Park and co-workers study and identify the adsorbate-driven morphological evolution of Cu nanoclusters on the Cu(997)surface,providing real-space evidence for the critical role of vicinal structures on Cu *** observed surface roughening trends caused by dissociated atomic oxygen and CO adsorbates subsequently affect the result of successive catalytic reactions to produce critical intermediates,such as carbonate and formate,during the CO_(2.reduction reaction.

关键词： reaction critical rational

A brief review on the recent development of phonon engineering and manipulation at nanoscales

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2024年第1期6卷 177-206页

作者： Siqi xie Hongxin Zhu Xing Zhang Haidong Wang Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084People’s Republic of China

Phonons are the quantum mechanical descriptions of vibrational modes that manifest themselves in many physical properties of condensed matter systems. As the size of electronic devices continues to decrease below mean free paths of acoustic phonons, the engineering of phonon spectra at the nanoscale becomes an important topic. Phonon manipulation allows for active control and management of heat fow, enabling functions such as regulated heat transport. At the same time, phonon transmission, as a novel signal transmission method, holds great potential to revolutionize modern industry like microelectronics technology, and boasts wide-ranging applications. Unlike fermions such as electrons, polarity regulation is difficult to act on phonons as bosons, making the development of effective phonon modulation methods a daunting *** work reviews the development of phonon engineering and strategies of phonon manipulation at different scales, reports the latest research progress of nanophononic devices such as thermal rectifiers, thermal transistors, thermal memories, and thermoelectric devices,and analyzes the phonon transport mechanisms involved. Lastly, we survey feasible perspectives and research directions of phonon engineering. Thermoelectric analogies, external field regulation, and acousto-optic co-optimization are expected to become future research hotspots.

关键词： phonon engineering phononic device nanoscale