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Acta Mechanica Solida Sinica 2023年第5期36卷 672-684页

作者： Di Chen Jun-jiang xiong School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China School of Transportation Science and Engineering Beihang UniversityBeijing 102206China

This paper seeks to investigate nonlinear out-of-plane mechanical behaviours of woven composite flexible skin(WCFS)through experimental and theoretical ***,quasi-static experiments are carried out on rectangular WCFSs with different aspect ratios under uniform normal pressure to measure out-of-plane deformation and failure ***,a new three-parameter geometric model is presented to describe 3D geometry of pressurized WCFS,and thus,a nonlinear mechanical model is deduced for depicting the relationship between pressure and out-of-plane *** application of the aforementioned models for experimental results shows that the new models have adequately and logically depicted deformation geometry and nonlinear mechanical characteristics.

关键词： Woven compositeﬂexible skin Nonlinear performance Uniform normal pressure Geometric model Mechanical model Aspect ratio

Delayed detached eddy simulations of fighter aircraft at high angle of attack

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Acta Mechanica Sinica 2016年第4期32卷 588-603页

作者： Guoliang Xu xiong jiang Gang Liu China Aerodynamics Research and Development Center

The massively separated flows over a realistic aircraft configuration at 40？, 50？, and 60？angles of attack are studied using the delayed detached eddy simulation（DDES）.The calculations are carried out at experimental conditions corresponding to a mean aerodynamic chord-based Reynolds number of 8.93 × 10~5 and Mach number of 0.088. The influence of the grid size is investigated using two grids, 20.0×10~6cells and 31.0 × 10~6 cells. At the selected conditions, the lift,drag, and pitching moment from DDES predictions agree with the experimental data better than that from the Reynoldsaveraged Navier–Stokes. The effect of angle of attack on the flow structure over the general aircraft is also studied, and it is found that the dominated frequency associated with the vortex shedding process decreases with increasing angle of attack.

关键词： aircraft turbulent Reynolds vortex turbulence averaged Navier unsteady realistic chord

Deformation-based freeform feature reconstruction in reverse engineering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1214-1228页

作者： Qing WANG jiang-xiong LI Ying-lin KE State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

For reconstructing a freeform feature from point cloud, a deformation-based method is proposed in this paper. The freeform feature consists of a secondary surface and a blending surface. The secondary surface plays a role in substituting a local region of a given primary surface. The blending surface acts as a bridge to smoothly connect the unchanged region of the primary surface with the secondary surface. The secondary surface is generated by surface deformation subjected to line constraints, i.e., character lines and limiting lines, not designed by conventional methods. The lines are used to represent the underlying informa-tion of the freeform feature in point cloud, where the character lines depict the feature’s shape, and the limiting lines determine its location and orientation. The configuration of the character lines and the extraction of the limiting lines are discussed in detail. The blending surface is designed by the traditional modeling method, whose intrinsic parameters are recovered from point cloud through a series of steps, namely, point cloud slicing, circle fitting and regression analysis. The proposed method is used not only to effectively and efficiently reconstruct the freeform feature, but also to modify it by manipulating the line constraints. Typical examples are given to verify our method.

关键词： Freeform feature Surface deformation Fishbone structure Character line Limiting line Reverse engineering

A simple algorithm to improve the performance of the WENO scheme on non-uniform grids

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Acta Mechanica Sinica 2018年第1期34卷 37-47页

作者： Wen-Feng Huang Yu-Xin Ren xiong jiang Tsinghua University Beijing 100084 China China Aerodynamics Research and Development Center Mianyang 621000 China

This paper presents a simple approach for improving the performance of the weighted essentially nonoscillatory(WENO) finite volume scheme on non-uniform grids. This technique relies on the reformulation of the fifthorder WENO-JS(WENO scheme presented by jiang and Shu in J. Comput. Phys. 126:202–228, 1995) scheme designed on uniform grids in terms of one cell-averaged value and its left and/or right interfacial values of the dependent *** effect of grid non-uniformity is taken into consideration by a proper interpolation of the interfacial values. On nonuniform grids, the proposed scheme is much more accurate than the original WENO-JS scheme, which was designed for uniform grids. When the grid is uniform, the resulting scheme reduces to the original WENO-JS scheme. In the meantime,the proposed scheme is computationally much more efficient than the fifth-order WENO scheme designed specifically for the non-uniform grids. A number of numerical test cases are simulated to verify the performance of the present scheme.

关键词： WENO scheme Non-uniform grids Shock capturing Finite volume methods

VGWO: Variant Grey Wolf Optimizer with High Accuracy and Low Time Complexity

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Computers, Materials & Continua 2023年第11期77卷 1617-1644页

作者： Junqiang jiang Zhifang Sun xiong jiang Shengjie Jin Yinli jiang Bo Fan School of Information Science and Engineering Hunan Institute of Science and TechnologyYueyang414006China Department of Computer and Information Science Linköping UniversityLinköping58183Sweden Department of Safety and Quality Hunan Construction Investment GroupChangsha410004China

The grey wolf optimizer(GWO)is a swarm-based intelligence optimization algorithm by simulating the steps of searching,encircling,and attacking prey in the process of wolf *** with its advantages of simple principle and few parameters setting,GWO bears drawbacks such as low solution accuracy and slow convergence speed.A few recent advanced GWOs are proposed to try to overcome these ***,they are either difficult to apply to large-scale problems due to high time complexity or easily lead to early *** solve the abovementioned issues,a high-accuracy variable grey wolf optimizer(VGWO)with low time complexity is proposed in this *** first uses the symmetrical wolf strategy to generate an initial population of individuals to lay the foundation for the global seek of the algorithm,and then inspired by the simulated annealing algorithm and the differential evolution algorithm,a mutation operation for generating a new mutant individual is performed on three wolves which are randomly selected in the current wolf individuals while after each iteration.A vectorized Manhattan distance calculation method is specifically designed to evaluate the probability of selecting the mutant individual based on its status in the current wolf population for the purpose of dynamically balancing global search and fast convergence capability of VGWO.A series of experiments are conducted on 19 benchmark functions from CEC2014 and CEC2020 and three real-world engineering *** 19 benchmark functions,VGWO’s optimization results place first in 80%of comparisons to the state-of-art GWOs and the CEC2020 competition winner.A further evaluation based on the Friedman test,VGWO also outperforms all other algorithms statistically in terms of robustness with a better average ranking value.

关键词： Intelligence optimization algorithm grey wolf optimizer(GWO) manhattan distance symmetric coordinates

New diterpenoid glucosides from Siegesbeckia pubescens

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Chinese Chemical Letters 2001年第1期12卷 51-54页

作者： jiang xiong Qi Duan JIN Yun Long XU Kunming Institute of Botany The Chinese Academy of SciencesKunming 650204

Five new diterpenoids isolated from Siegesbeckia pubescens, pubesides A similar toE, were established as ent-2 alpha ,15,16-trihydroxypimar-8(14)-en-2-O-beta -D-glucopyranoside (1), ent-15,16,19-trihydroxypimar-8(14)-en-19-O-beta -D-glucopyranoside (2), beta -D-glucopyranosyl-ent-15,16-dihydroxypimar-8(14)-en-19-oiclate (3), ent-2-oxo-15,16,19-trihydroxypimar-8(14)-en-19-O-beta -D-gluco-pyranoside (4), ent-2-oxo-15,16,19-trihydroxypimar-8(14)-en-19-O-beta -D-glucopyranoside-15,16-acetonide (5) by 1D and 2D NMR techniques.

关键词： Siegesbeckia pubescens new diterpenoid glucosides pubesides A~E

Foci of Future Studies on Abiotic Stress Tolerance of Maize in the Era of Post-Genomics

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Journal of Integrative Agriculture 2012年第8期11卷 1236-1244页

作者： LI You-zhi FAN Xian-wei LIAO jiang-xiong State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Ministry of Science and Technology/Key Laboratory of Microbial and Plant Genetic Engineering Ministry of Education/College of Life Science and Technology Guangxi University Guangxi 530005 P.R. China Sugarcane Research Center Chinese Academy of Agriculture Sciences Guangxi 530007 P.R.China

Genetic and metabolic engineering approaches are powerful tools for improving the tolerance of maize to abiotic stresses because they are faster and can afford greater control over agronomically useful traits. However, in-depth understanding of the molecular mechanisms controlling response to abiotic stresses is the prerequisite for successful implementation of these strategies. A great flaw to dissect the biological mechanisms by genome sequencing is that genome sequencing approach could not reflect real-time molecular actions of plants especially under the stresses because the living organisms rarely live in unchanging environments. Post-genomics such as transcriptomics, metabolomics, and proteomics can generate knowledge that is closer to the biological processes. With the development of post-genomics, it can be expected that voluminous data will be generated. This paper proposes that future research on maize stress tolerance in the era of post-genomics should focus on metabolomics and proteomics; stress tolerance of whole plant rather than individual tissues or organs; coordination of expression of genes among tissues; characterization of promoters of stress-responsive genes; interrelation between mechanisms for tolerance to, and growth recovery from the stress; hexose metabolism as well as the glycolysis pathway; and foundation genotypes.

关键词： maize abiotic stresses research foci era of post-genomics

Blood-Letting Therapy for Hypertension: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

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Chinese Journal of Integrative Medicine 2019年第2期25卷 139-146页

作者： xiong Xing-jiang WANG Peng-qian LI Sheng-jie Department of Cardiology Guang'anmen HospitalChina Academy of Chinese Medical Sciences Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Department of Molecular Biology Peking Union Medical College HospitalChinese Academy of Medical Sciences

Objective:To evaluate the efficacy and safety of blood-letting therapy(BLT)in treatment of ***:A comprehensive electronic and manual bibliographic searches were performed in Cochrane Central Register of Controlled Trials,Excerpt Medica Database(EMBASE),PubMed,China National Knowledge Infrastructure,Chinese Scientific Journal Database,Chinese Biomedical Literature Database,and Wanfang Database to identify randomized controlled trials(RCTs)in which hypertensive patients were treated with BLT or BLT plus antihypertensive drugs(BPAD)against placebo,no treatment or antihypertensive *** Cochrane Risk Assessment Tool was used to assess the methodological quality of *** Review Manager 5.3 software was used for ***:A total of 7 RCTs with 637 hypertensive patients from 1989 to 2017 were *** with antihypertensive drugs,blood pressure was significantly reduced by BLT(RR=1.21,95%CI:1.01 to 1.44,P=0.03;heterogeneity:P=0.06,I^2=60%)and BPAD(RR=1.25,95%CI,1.02 to 1.53,P=0.03;heterogeneity:P=0.01,I^2=71%).Moreover,a significant improvement in Chinese medicine syndrome by BLT(RR=1.32;95%CI:1.14 to 1.53,P=0.0002;heterogeneity:P=0.53,I^2=0%)and BPAD(RR=1.47;95%CI:1.06 to 2.04,P=0.02;heterogeneity:P=0.13,I^2=56%)was *** reported adverse effects were well ***:Although some positive findings were identified,no definite conclusions regarding the efficacy and safety of BLT as complementary and alternative approach for treatment of hypertension could be drew due to the generally poor methodological design,significant heterogeneity,and insufficient clinical *** rigorously designed trials are warranted to confirm the results.

关键词： blood-letting therapy phlebotomy blood pressure Chinese medicine complementary and alternative medicine systematic review meta-analysis randomized controlled trials

New approaches in agent-based modeling ofcomplex financial systems

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Frontiers of physics 2017年第6期12卷 115-126页

作者： Ting-Ting Chen Bo Zheng Yan Li xiong-Fei jiang Department of Physics Zhejiang University Hangzhou 310027 China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093 China

Agent-based modeling is a powerful simulation technique to understand the collective behavior and microscopic interaction in complex financial systems. Recently, the concept for determining the key parameters of agent-based models from empirical data instead of setting them artificially was sug- gested. We first review several agent-based models and the new approaches to determine the key model parameters from historical market data. Based on tile agents＇ behaviors with heterogeneous personal preferences and interactions, these models are successful in explaining the microscopic origi- nation of the temporal and spatial correlations of financial markets. We then present a novel paradigm combining big-data analysis with agent-based modeling. Specifically, from internet query and stock market data, we extract the information driving forces and develop an agent-based model to simulate the dynamic behaviors of complex financial systems.

关键词： econophysics complex systems

Stabilising control for a class of chaotic systems based on adaptive fuzzy logic systems

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Journal of Control and Decision 2016年第3期3卷 165-178页

作者： Zilin Gao Yinhe Wang jiang xiong Yong Pan School of Computer Science and Engineering Chongqing Three Gorges UniversityWanzhouChina School of Automation Guangdong University of TechnologyGuangzhouChina

For a class of chaotic systems with unknown functions and disturbances,asymptotic stabilisation of the chaotic systems is achieved by designing a stability controller based on the adaptive fuzzy logic *** first,based on the universal approximation property of fuzzy logic systems,the Mamdani-type fuzzy logic systems with the parameter adaptive laws are designed utilising the data information sampled from the inputs and outputs of unknown functions in the chaotic systems,then the fuzzy logic systems are used to design the stability controller with three parameter adaptive laws,but the three parameters have no relationship with the number of fuzzy rules,so the stability controller is not only able to achieve asymptotic stabilisation for the chaotic system’s states,but also to reduce the number of fuzzy rules and the no-line computational burden ***,simulations are used to show the validity of the stabilisation method.

关键词： Chaotic systems asymptotic stabilisation adaptive fuzzy logic systems simulation