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Solitonic attractors in the coupled nonlinear Schrödinger equations with weak dissipations

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Communications in Theoretical Physics 2023年第6期75卷 22-26页

作者： kai-Yuan qi Xian-kun Yao Li-Chen Zhao Zhan-Ying Yang School of Physics Northwest UniversityXi’an 710127China NSFC-SPTP Peng Huanwu Center for Fundamental Theory Xi’an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi’an 710127China

We use the Lagrangian perturbation method to investigate the properties of soliton solutions in the coupled nonlinear Schrödinger equations subject to weak *** study reveals that the two-component soliton solutions act as fixed-point attractors,where the numerical evolution of the system always converges to a soliton solution,regardless of the initial ***,the fixed-point attractor appears as a soliton solution with a constant sum of the two-component intensities and a fixed soliton velocity,but each component soliton does not exhibit the attractor feature if the dissipation terms are *** suggests that one soliton attractor in the coupled systems can correspond to a group of soliton solutions,which is different from scalar *** findings could inspire further discussions on dissipative-soliton dynamics in coupled systems.

关键词： coupled nonlinear systems weak dissipation solitonic attractor

VFM： Visual Feedback Model for Robust Object Recognition

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Journal of Computer Science & Technology 2015年第2期30卷 325-339页

作者：王冲黄凯奇 National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100190 China

Object recognition, which consists of classification and detection, has two important attributes for robustness： 1） closeness： detection windows should be as close to object locations as possible, and 2） adaptiveness： object matching should be adaptive to object variations within an object class. It is difficult to satisfy both attributes using traditional methods which consider classification and detection separately; thus recent studies propose to combine them based on confidence contextualization and foreground modeling. However, these combinations neglect feature saliency and object structure, and biological evidence suggests that the feature saliency and object structure can be important in guiding the recognition from low level to high level. In fact, object recognition originates in the mechanism of ＂what＂ and ＂where＂ pathways in human visual systems. More importantly, these pathways have feedback to each other and exchange useful information, which may improve closeness and adaptiveness. Inspired by the visual feedback, we propose a robust object recognition framework by designing a computational visual feedback model （VFM） between classification and detection. In the ＂what＂ feedback, the feature saliency from classification is exploited to rectify detection windows for better closeness; while in the ＂where＂ feedback, object parts from detection are used to match object structure for better adaptiveness. Experimental results show that the ＂what＂ and ＂where＂ feedback is effective to improve closeness and adaptiveness for object recognition, and encouraging improvements are obtained on the challenging PASCAL VOC 2007 dataset.

关键词： object recognition object classification object detection visual feedback

Modeling of bistatic scattering from an underwater non-penetrable target using a Kirchhoff approximation method

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Defence Technology（防务技术） 2022年第7期18卷 1097-1106页

作者： Bin Wang Wen-huan Wang Jun Fan kai-qi Zhao Fu-lin Zhou Li-wen Tan Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration State Key Laboratory of Ocean EngineeringShanghai Jiao Tong UniversityShanghai200240China

A numerical triangulation and transformation into the time domain of a Kirchhoff approximation(KA)method is proposed for the modeling of bistatic scattering from an underwater non-penetrable *** time domain solution in this approximation can be split up into two parts:the solution of reflected field,contributing around the specular direction,and the solution of shadow radiation,contributing around the forward *** average solution in the time domain satisfying the reciprocity principle is *** solution is expressed in terms of non-singular *** proposed method is validated against a normal mode method for bistatic scattering from a rigid ***,the reflected and shadow highlights on the surface of the sphere are shown to verify the integration surface of the reflected field and shadow *** is also tested against a finite element method and an experiment involving a scaled Benchmark Target Strength Simulation Submarine *** time-angle bistatic spectra for the model are evaluated by the direct and transformed average solutions of KA,and the former accelerates its speed of *** results are good,and show that this method can be used to predict the bistatic scattered field of a non-penetrable target.

关键词： Kirchhoff approximation Bistatic scattering Time domain Reciprocity Experiment

GAM:A GPU-Accelerated Algorithm for MaxRS Queries in Road Networks

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Journal of Computer Science & Technology 2022年第5期37卷 1005-1025页

作者： Jian Chen kai-qi Zhang Tian Ren Zhen-qing Wu Hong Gao School of Computer Science and Technology Harbin Institute of TechnologyHarbin150001China

In smart phones,vehicles and wearable devices,GPS sensors are ubiquitous and collect a lot of valuable spatial data from the real *** a set of weighted points and a rectangle r in the space,a maximizing range sum(MaxRS)query is to find the position of r,so as to maximize the total weight of the points covered by r(i.e.,the range sum).It has a wide spectrum of applications in spatial crowdsourcing,facility location and traffic *** of the existing research focuses on the Euclidean space;however,in real life,the user’s moving route is constrained by the road network,and the existing MaxRS query algorithms in the road network are *** this paper,we propose a novel GPU-accelerated algorithm,namely,GAM,to tackle MaxRS queries in road networks in two phases *** phase 1,we partition the entire road network into many small cells by a grid and theoretically prove the correctness of parallel query results by grid shifting,and then we propose an effective multi-grained pruning technique,by which the majority of cells can be pruned without further *** phase 2,we design a GPU-friendly storage structure,cell-based road network(CRN),and a two-level parallel framework to compute the final result in the remaining ***,we conduct extensive experiments on two real-world road networks,and the experimental results demonstrate that GAM is on average one order faster than state-of-the-art competitors,and the maximum speedup can achieve about 55 times.

关键词： road network maximizing range sum GPU acceleration pruning strategy

Synthesis and Self-assembly of a Linear Coil-Coil-Rod ABC Triblock Copolymer

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Chinese Journal of Polymer Science 2014年第11期32卷 1524-1534页

作者： Ling-ying Shi Yu Pan qi-kai Zhang Yu Zhou Xing-he Fan 沈志豪 Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking University College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University

An interesting order-order transition between two different complex nanostructures was observed in a new liquid crystalline linear coil-coil-rod ABC triblock copolymer（tri BCP）. First, the ABC tri BCP, poly（dimethylsiloxane）-bpolystyrene-b-poly{2,5-bis[（4-methoxyphenyl）oxycarbonyl]styrene}（PDMS-b-PS-b-PMPCS）, was synthesized through sequential atom transfer radical polymerization. The degrees of polymerization of PDMS, PS, and PMPCS blocks are 58, 159, and 106, and the corresponding volume fractions of PDMS, PS, and PMPCS are 0.09, 0.29, and 0.62, respectively. The phase behaviors of the PDMS-b-PS diblock copolymer precursor and the final triblock copolymer were studied by smallangle X-ray scattering, one-dimensional wide-angle X-ray scattering, and transmission electron microscopy experiments. The PDMS-b-PS precursor self-assembles into hexagonally packed cylinders with a relatively small periodic size after thermal annealing. When the triblock copolymer is annealed at a relatively low temperature（120 ○C） at which the PMPCS block is in the amorphous state, the tri BCP forms core-shell hexagonally packed cylinders（CSH） with a relativly large periodic size. After the tri BCP is annealed above 140 ○C at which the PMPCS block transforms to the liquid crystalline（LC） phase, the nanophase-separated structure transforms to a three-phase four-layer lamellar structure（LAM-3P4L）. Thus, accompanied with the transition of the PMPCS blocks from the amorphous state to the LC phase, the order-order transition from CSH to LAM-3P4 L occurs in the PDMS-b-PS-b-PMPCS ABC tri BCP.

关键词： Coil-coil-rod triblock copolymer Self-assembly Order-order transition Liquid crystalline polymer Complex nanostructures.

AI in Human-computer Gaming:Techniques,Challenges and Opportunities

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Machine Intelligence Research 2023年第3期20卷 299-317页

作者： qi-Yue Yin Jun Yang kai-qi Huang Mei-Jing Zhao Wan-Cheng Ni Bin Liang Yan Huang Shu Wu Liang Wang Institute of Automation Chinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Department of Automation Tsinghua UniversityBeijing 100084China Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of SciencesBeijing 100190China

With the breakthrough of AlphaGo,human-computer gaming AI has ushered in a big explosion,attracting more and more researchers all over the *** a recognized standard for testing artificial intelligence,various human-computer gaming AI systems(AIs)have been developed,such as Libratus,OpenAI Five,and AlphaStar,which beat professional human *** rapid development of human-computer gaming AIs indicates a big step for decision-making intelligence,and it seems that current techniques can handle very complex human-computer ***,one natural question arises:What are the possible challenges of current techniques in human-computer gaming and what are the future trends?To answer the above question,in this paper,we survey recent successful game AIs,covering board game AIs,card game AIs,first-person shooting game AIs,and real-time strategy game *** this survey,we 1)compare the main difficulties among different kinds of games and the corresponding techniques utilized for achieving professional human-level AIs;2)summarize the mainstream frameworks and techniques that can be properly relied on for developing AIs for complex human-computer games;3)raise the challenges or drawbacks of current techniques in the successful AIs;and 4)try to point out future trends in human-computer gaming ***,we hope that this brief review can provide an introduction for beginners and inspire insight for researchers in the field of AI in human-computer gaming.

关键词： Human-computer gaming AI intelligent decision making deep reinforcement learning self-play

Tectono-Thermal Evolution, Hydrocarbon Filling and Accumulation Phases of the Hari Sag, in the Yingen-Ejinaqi Basin, Inner Mongolia,Northern China

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 1157-1169页

作者： YANG Peng REN Zhanli XIA Bin TIAN Tao ZHANG Yong qi kai REN Wenbo State Key Laboratory of Continental Dynamics Department of Geology Northwest University Guangdong Key Laboratory of Offshore Oil Exploration and Development School of Marine ScienceSun Yat-sen University Radiogenic Isotope Facility School of Earth and Environmental Sciences The University of Queensland State Key Laboratory of Ore Deposit Geochemistry Chinese Academy of Sciences Key Laboratory Coal Resource Exploration and comprehensive Utilization Ministry of Land and Resources

This work restored the erosion thickness of the top surface of each Cretaceous formations penetrated by the typical well in the Hari sag, and simulated the subsidence burial history of this well with software BasinMod. It is firstly pointed out that the tectonic subsidence evolution of the Hari sag since the Cretaceous can be divided into four phases: initial subsidence phase, rapid subsidence phase,uplift and erosion phase, and stable slow subsidence phase. A detailed reconstruction of the tectonothermal evolution and hydrocarbon generation histories of typical well was undertaken using the EASY R% model, which is constrained by vitrinite reflectance(R) and homogenization temperatures of fluid inclusions. In the rapid subsidence phase, the peak period of hydrocarbon generation was reached at c.a.105.59 Ma with the increasing thermal evolution degree. A concomitant rapid increase in paleotemperatures occurred and reached a maximum geothermal gradient of about 43-45℃/km. The main hydrocarbon generation period ensued around 105.59-80.00 Ma and the greatest buried depth of the Hari sag was reached at c.a. 80.00 Ma, when the maximum paleo-temperature was over 180℃.Subsequently, the sag entered an uplift and erosion phase followed by a stable slow subsidence phase during which the temperature gradient, thermal evolution, and hydrocarbon generation decreased gradually. The hydrocarbon accumulation period was discussed based on homogenization temperatures of inclusions and it is believed that two periods of rapid hydrocarbon accumulation events occurred during the Cretaceous rapid subsidence phase. The first accumulation period observed in the Bayingebi Formation(Kb) occurred primarily around 105.59-103.50 Ma with temperatures of 125-150℃. The second accumulation period observed in the Suhongtu Formation(Ks) occurred primarily around84.00-80.00 Ma with temperatures of 120-130℃. The second is the major accumulation period, and the accumulation mainly occurred in the Late Cr

关键词： fluid inclusion erosion thickness subsidence burial history tectono-thermal evolution hydrocarbon generation history hydrocarbon accumulation phase Inner Mongolia China

Thermocatalytic Dehydrogenation-Enabled Arene-Alkane Couplings

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Chinese Journal of Chemistry 2023年第16期41卷 1905-1914页

作者： Feng Yu Renqing Tao Lan Gan Hao Ni qi-kai Kang Guixia Liu Zheng Huang Chang-Kung Chuang Institute East China Normal UniversityShanghai 200062China The State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China School of Chemistry and Material Sciences Hangzhou Institute of Advanced StudyUniversity of Chinese Academy of Sciences1 Sub-lane XiangshanHangzhouZhejiang 310024China

Comprehensive Summary The direct use of non-prefunctionalized arene and alkane as the starting materials to construct Caryl−Calkyl bond is an unfulfilled target and approaches to this challenge rarely surface in methodology *** methods for thermocatalytic arene-alkane couplings(AAC)occur with specific substrates and/or inconvenient ***,we report a one-pot relay bicatalysis system for AAC involving(pincer)Ir-catalyzed alkane transfer dehydrogenation and Fe(OTf)3-catalyzed olefin *** system exhibits broad scope and is particularly effective for alkylation of arenes with arylalkanes to form 1,1-diarylalkanes with high chemo-and regioselectivity,making it potentially useful for late-stage alkylation of complex *** mechanistic data provide a view into the factors controlling the ***,the strategy of dehydrogenation-enabled arene-alkane couplings has been successfully extended to a tandem catalysis by using a heterogeneous olefin hydroarylation catalyst.

关键词： Alkanes Arenes Dehydrogenative coupling Hydroarylation lridium

Meso-Cenozoic Tectonothermal History of Permian Strata, Southwestern Weibei Uplift: Insights from Thermochronology and Geothermometry

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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1647-1661页

作者： YU qiang REN Zhanli LI Rongxi TAO Ni qi kai JIANG Cheng WANG Baojiang The School of Earth Science and Resources Chang’an UniversityXi’an 710054China Key Laboratory of Western China's Mineral Resources and Geological Engineering Ministry of EducationChang'an UniversityXi'an 710054China State Key Laboratory of Continental Dynamics Northwest UniversityXi'an 710069China Department of Geology Northwest UniversityXi’an710069China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400030China State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam Chongqing UniversityChongqing 400030China Research Institute of Yanchang Petroleum(Group)Company Limited Xi’anSichuan710075China

This study provides an integrated interpretation for the Mesozoic-Cenozoic tectonothermal evolutionary history of the Permian strata in the qishan area of the southwestern Weibei Uplift,Ordos *** fission-track and apatite/zircon(U-Th)/He thermochronometry,bitumen reflectance,thermal conductivity of rocks,paleotemperature recovery,and basin modeling were used to restore the Meso-Cenozoic tectonothermal history of the Permian *** Triassic AFT data have a pooled age of^180±7 Ma with one age peak and P(χ2)=86%.The average value of corrected apatite(U-Th)/He age of two Permian sandstones is^168±4 Ma and a zircon(U-Th)/He age from the Cambrian strata is^231±14 *** reflectance and maximum paleotemperature of two Ordovician mudstones are 1.81%,1.57%and^210℃,~196℃*** undergoing a rapid subsidence and increasing temperature in Triassic influenced by intrusive rocks in some areas,the Permian strata experienced four cooling-uplift stages after the time when the maximum paleotemperature reached in late Jurassic:(1)A cooling stage(~163 Ma to^140 Ma)with temperatures ranging from^132℃to^53℃and a cooling rate of^3℃/Ma,an erosion thickness of^1900 m and an uplift rate of^82 m/Ma;(2)A cooling stage(~140 Ma to^52 Ma)with temperatures ranging from^53℃to^47℃and a cooling rate less than^0.1℃/Ma,an erosion thickness of^300 m and an uplift rate of^3 m/Ma;(3)(~52 Ma to^8 Ma)with^47℃to^43℃and^0.1℃/Ma,an erosion thickness of^500 m and an uplift rate of^11 m/Ma;(3)(~8 Ma to present)with^43℃to^20℃and^3℃/Ma,an erosion thickness of^650 m and an uplift rate of^81 m/*** tectonothermal evolutionary history of the qishan area in Triassic was influenced by the interaction of the qinling Orogeny and the Weibei Uplift,and the south qishan area had the earliest uplift-cooling time compared to other parts within the Weibei *** early Eocene at^52 Ma and the late Miocene at^8 Ma,as two significant turning points after which both the rate of uplift and the rat

关键词： low temperature thermochronology fission track (U-Th)/He basin modeling cooling history uplift Ordos Basin