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Frontiers of physics 2017年第6期12卷 139-161页

作者： Chen Xin ji-ping Huang Department of Physics and State Key Laboratory of Surface Physics Fudan University Shanghai 200433 China

Agent-based modeling and controlled human experiments serve as two fundamental research methods in the field of econophysics. Agent-based modeling has been in development for over 20 years, but how to design virtual agents with high levels of human-like ＂intelligence＂ remains a challenge. On the other hand, experimental econophysics is an emerging field; however, there is a lack of experience and paradigms related to the field. Here, we review some of the most recent research results obtained through the use of these two methods concerning financial problems such as chaos, leverage, and business cycles. We also review the principles behind assessments of agents＇ intelligence levels, and some relevant designs for human experiments. The main theme of this review is to show that by combining theory, agent-based modeling, and controlled human experiments, one can garner more reliable and credible results on account of a better verification of theory; accordingly, this way, a wider range of economic and financial problems and phenomena can be studied.

关键词： agent-based modeling controlled human experiment minority game econophysics chaos,leverage business cycle

Robustness of critical points in a complex adaptive system： Effects of hedge behavior

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Frontiers of physics 2013年第4期8卷 461-466页

作者： Yuan Liang ji-ping Huang Department of Physics and State Key Laboratory of Surface Physics Fudan University Shanghai 200433 China Department of Physics College of Science Donghua University Shanghai 201602 China

In our recent papers, we have identified a class of phase transitions in the market-directed resource- allocation game, and found that there exists a critical point at which the phase transitions occur. The critical point is given by a certain resource ratio. Here, by performing computer simulations and theoretical analysis, we report that the critical point is robust against various kinds of human hedge behavior where the numbers of herds and contrarians can be varied widely. This means that the critical point can be independent of the total number of participants composed of normal agents, herds and contrarians, under some conditions. This finding means that the critical points we identified in this complex adaptive system （with adaptive agents） may also be an intensive quantity, similar to those revealed in traditional physical systems （with non-adaptive units）.

关键词： complex adaptive system phase transition resource allocation hedge behavior agent-based simulation

Microstructure and mechanical properties of twin-wire arc sprayed Ni-Al composite coatings on 6061-T6 aluminum alloy sheet

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 469-478页

作者： ji-xiao Wang jing-shun liu Lun-yong Zhang jian-fei Sun Zhi-ping Wang School of Materials Science and Engineering Harbin Institute of Technology Harbin Welding Institute China Academy of Machinery Science & Technology School of Materials Science and Engineering Inner Mongolia University of Technology National Laboratory of Solid State Microstructures & Department of Materials Science and Engineering Nanjing University College of science Civil Aviation University of China

We have systematically studied the microstructure and mechanical properties of Ni-5wt%Al and Ni-20wt%Al composite coat- ings fabricated on 6061-T6 aluminum alloy sheet by twin-wire arc spraying under different experimental conditions. The abrasive wear be- havior and interface diffusion behavior of the composite coatings were evaluated by dry/wet rubber wheel abrasive wear tests and heat treat- ment, respectively. Experimental results indicate that the composite coatings exhibit features of adhesive wear. Besides, the Vickers micro- hardness of NiA1 and Ni3AI intermetallic compounds is relatively larger than that of the substrate, which is beneficial for enhancing the wear resistance. With the increase of annealing temperature and time, the interface diffusion area between the Ni-Al coating and the substrate gradually expands with the formation of NiAl3 and Ni2Al3 phases, and is controlled by diffusion of aluminum atoms. The grain growth ex- ponent n of diffusion kinetics of the Ni-Al coating, calculated via a high-temperature diffusion model at 400, 480, and 550℃, is between 0.28 and 0.38. This satisfies the cubic law, which is consistent with the general theoretical relationship of high-temperature diffusion.

关键词： composite coatings intermetallics spraying aluminum alloys mechanical properties diffusion

Instance Segmentation and Berry Counting of Table Grape before Thinning Based on AS-SwinT

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Plant Phenomics 2023年第4期5卷 703-713页

作者： Wensheng Du ping liu Shandong Agricultural Equipment Intelligent Engineering Laboratory Shandong Provincial Key Laboratory of HorticulturalMachinery and EquipmentCollege of Mechanical and Electronic EngineeringShandong Agricultural UniversityTai'an 271000China School of Construction Machinery Shandong Jiaotong UniversityJinan 250357China

Berry thinning is one of the most important tasks in the management of high-quality table *** often thin the berries per cluster to a standard number by *** an aging population,it is hard to find adequate skilled farmers to work during thinning *** is urgent to design an intelligent berry-thinning machine to avoid exhaustive repetitive labor.A machine vision system that can determine the number of berries removed and locate the berries removed is a challenge for the thinning machine.A method for instance segmentation of berries and berry counting in a single bunch is proposed based on *** AS-Swin T,Swin Transformer is performed as the backbone to extract the rich characteristics of grape *** adaptive feature fusion is introduced to the neck network to sufficiently preserve the underlying features and enhance the detection of small *** size of berries in the dataset is statistically analyzed to optimize the anchor scale,and Soft-NMS is used to filter the candidate frames to reduce the missed detection of densely shaded ***,the proposed method could achieve 65.7 AP^(box),95.0 AP^(box)_(0.5),57 AP^(box)_(s),62.8 AP^(mask)94.3 AP^(mask)_(0.5),48 AP^(mask)_(s),which is markedly superior to Mask R-CNN,Mask Scoring R-CNN,and Cascade Mask *** regressions between predicted numbers and actual numbers are also developed to verify the precision of the proposed *** and R^(2)values are 7.13 and 0.95,respectively,which are substantially higher than other models,showing the advantage of the AS-SwinT model in berry counting estimation.

关键词： Berry network removed

Data-driven Stochastic Programming with Distributionally Robust Constraints Under Wasserstein Distance:Asymptotic Properties

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Journal of the Operations Research Society of China 2021年第3期9卷 525-542页

作者： Yu Mei Zhi-ping Chen Bing-Bing ji Zhu-jia Xu jia liu Department of Computing Science School of Mathematics and StatisticsXi’an Jiaotong UniversityXi’an 710049China Center for Optimization Technique and Quantitative Finance Xi’an International Academy for Mathematics and Mathematical TechnologyXi’an 710049China

Distributionally robust optimization is a dominant paradigm for decision-making problems where the distribution of random variables is *** investigate a distributionally robust optimization problem with ambiguities in the objective function and countably infinite *** ambiguity set is defined as a Wasserstein ball centered at the empirical *** on the concentration inequality of Wasserstein distance,we establish the asymptotic convergence property of the datadriven distributionally robust optimization problem when the sample size goes to *** show that with probability 1,the optimal value and the optimal solution set of the data-driven distributionally robust problem converge to those of the stochastic optimization problem with true ***,we provide numerical evidences for the established theoretical results.

关键词： Distributionally robust optimization Wasserstein distance Ambiguity set Asymptotic analysis Empirical distribution

The study of methanol aromatization on transition metal modified ZSM-5 catalyst

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Chinese Journal of Chemical Engineering 2018年第9期26卷 1949-1953页

作者： Keming ji jiayao Xun ping liu Qingwen Song Junhua Gao Kan Zhang jingyuan Li State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences

In this article, transition metals of Cu, La and Zn were used as adjuvant to prepare modified HZSM-5 by impregnation method. The catalysts were characterized by XRD, BET, NH_3-TPD and Py-IR to reveal the microstructure and acid property. The catalysis performances of methanol aromatization of catalysts were investigated in a fixed-bed reactor. The results show that the strength and distribution of acid center of these catalysts are significantly influenced by the species of transition metal. There are more mediate strong Lewis acid center in Zn modified HZSM-5 catalyst and therefore exhibits higher selectivity to aromatic, benzene, toluene and xylenes in the MTA reaction..

关键词： Aromatization ZSM-5 Metal modified

Monoclonal antibody-based serological detection of Citrus yellow vein clearing virus in citrus groves

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Journal of Integrative Agriculture 2017年第4期16卷 884-891页

作者： liu Zhen SUNZHU Yuan-ji ZHOU Xue-ping HONG jian WU jian-xiang State Key Laboratory of Rice Biology Institute of Biotechnology Zhejiang University Hangzhou 310058 P.R. China

Citrus yellow vein clearing virus （CYVCV） is considered as the causal agent of Citrus yellow vein clearing disease and belongs to the genus Mandarivirus in the family Alphaflexiviridae. Capsid protein （CP） of CYVCV Chongqing isolate （CYVCV- CQ） was produced using a prokaryotic expression system and used as the immunogen for monoclonal antibody （MAb） production. Four highly specific and sensitive murine MAbs and one polyclonal antibody were prepared in this study. Titers of the four MAbs in ascites fluids ranged from 10-6 to 10-7 as determined by indirect enzyme-linked immunosorbent assay （ELISA）. Three serological assays, including dot enzyme-linked immunosorbent assay （dot-ELISA）, tissue blot-ELISA, and double-antibody sandwich （DAS）-ELISA, were developed for quick and reliable detections of CYVCV in citrus samples. The developed dot-ELISA and DAS-ELISA methods could detect CYVCV in the infected citrus leaf crude extracts diluted at 1：2 560 and 1：10 240 （w/v, g mL^-1）, respectively. The detection result of 125 citrus leaf samples collected from citrus groves in Yunnan Province and Chongqing Municipality of China showed that approximately 36% samples were positive for CYVCV. This virus was, however, not＇detected in any sample collected from Zhejiang or jiangxi Province, China.

关键词： Citrus yellow vein clearing virus monoclonal antibody serological assay

Sites of Protonation and Unimolecular Fragmentation of Protonated N-Hydroxyphthalimide in the Gas Phase

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Chemical Research in Chinese Universities 1998年第2期14卷 63-67页

作者： SHE Yi-min SUN Yu-quan ji Yi-ping liu Shu-ying Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun130022

The low energy collisioninduced dissociation, linked scan techniques and isotopic labeling experiment were used to investigate the unimolecular fragmentation of protonated N-hydroxyphthalimide under electron impact and chemical ionization conditions. It was found that this compound shows an unusual reactivity towards protonation. Two possible sites of protonation have been proposed to explain the corresponding fragmentation processes, one is that the protonation takes place on the oxygen atom of hydroxyl group, resulting in the loss of water and the other is the formation of an intermediary protonbound complex in the fragmentation process, giving rise to the fragment ions of m/z 133 and m/z 135. The results show both cases are coexistence in the fragmentations of protonated N-hydroxyphthalimide, and the unimolecular fragmentation pathways are available.

关键词： Sites of protonation Unimolecular fragmentation Collisioninduced dissociation Nhydroxyphthalimide

Theoretical Calculations of Optical Spectra and Their Pressure-Induced Shifts of MgAl_2O_4:Cr^(3+)

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Communications in Theoretical Physics 2008年第5期49卷 1339-1344页

作者： WU Fei ZHANG ji-ping College of Physical Science and Technology Sichuan University Chengdu 610065 China

The energy levels of spectrum, wavefunetions and crystal-field parameters of MgAl2O4：Cr^3＋ at normal pressure have been calculated by the means of diagonalizing the complete d^3 energy matrix （DCEM）. With these results, the g factor of the ground state at normal pressure and the pressure-induced shift （PS） of the spectra1 levels are also calculated uniformly, and the calculated results are all in good agreement with the experimental ones. And the contributions of various crystal-field parameters to the energy levels at normal pressure and the variational rates of the R1 line shifting with the pressure are calculated, from which the physical origin of the red shift of the R1 line shifting with increasing pressure have been clearly shown.

关键词： crystal fields energy spectrum g factor high-pressure effect

Quantum anomalous energy effects on the nucleon mass

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Science China(Physics,Mechanics & Astronomy) 2021年第8期64卷 23-28页

作者： Xiangdong ji Yizhuang liu Center for Nuclear Femtography Southeastern Universities Research AssociationWashington DC 20005USA Department of Physics University of MarylandCollege ParkMD 20742USA Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Institute fur Theoretische Physik Universitat RegensburgRegensburg D-93040Germany

Apart from the quark and gluon kinetic and potential energies, the nucleon mass includes a novel energy of pure quantum origin resulting from anomalous breaking of scale symmetry. We demonstrate the effects of this quantum anomalous energy(QAE) in QED, as well as in a toy 1+1 dimensional non-linear sigma model where it contributes non-perturbatively, in a way resembling the Higgs mechanism for the masses of matter particles in electro-weak theory. The QAE contribution to the nucleon mass can be explained using a similar mechanism, in terms of a dynamical response of the gluonic scalar field through Higgs-like couplings between the nucleon and scalar resonances. In addition, the QAE sets the scale for other energies in the nucleon through a relativistic virial theorem, and contributes a negative pressure to confine the colored quarks.

关键词： proton mass quantum anomaly spontaneous symmetry breaking scale symmetry