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Influence of Novel Redirector with Bypass Damping on the Performance of Load-Sensing Steering System

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Chinese Journal of Mechanical Engineering 2021年第5期34卷 360-375页

作者： yuqi wang Xinhui Liu Jinshi Chen Dongyang Huo School of Mechanical and Aerospace Engineering Jilin UniversityJilin 130022China

Load-sensing steering systems for articulated loaders are prone to large pressure shocks and oscillations during steering operations,affecting the system *** optimized structure of the redirector with bypass damping is proposed to improve this *** this structure,orifices and throttle grooves are added to the traditional *** control the steering load and working conditions,the steering load of the loader is replaced by a pressure regulating *** and experimental results reveal that the redirector with bypass damping has better load-sensing characteristics than the traditional *** peak output pressure shock caused by the load unit step signal decreases from 6.50 to 5.64 MPa,which means the pressure oscillation of the hydraulic system is reduced by 13.4%.The pressure fluctuation time can be reduced from 2.09 to 1.6 s,with a decrease rate of 23.4%.The output pressure oscillation decays swiftly,and the smoothness of the steering operation is improved significantly.

关键词： Articulated vehicle Redirector Load-sensing steering system Pressure oscillation

Hunting field: insights on distribution pattern of bacteria and immune cells in solid tumors

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National Science Review 2021年第5期8卷 18-21页

作者： Yang Li yuqi wang Xuefei Li Chenli Liu CAS Key Laboratory for Quantitative Engineering Biology Shenzhen Institute of Synthetic BiologyShenzhen Institutes of Advanced TechnologyChinese Academy of Sciences University of Chinese Academy of Sciences

Bacterial cancer therapy, which was first applied in the clinic in 1868, has regained attention owing to the recent progress made in synthetic *** their easily manipulated genomes, preferential accumulation in tumors,...

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Fluctuation assisted collapses of Bose-Einstein condensates

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Communications in Theoretical Physics 2022年第9期74卷 199-206页

作者： Junqiao Pan yuqi wang Tao Shi Su Yi CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China

We study the collapse dynamics of a Bose-Einstein condensate subjected to a sudden change of the scattering length to a negative value by adopting the self-consistent Gaussian state theory for mixed *** to the Gross-Pitaevskii and the Hartree-Fock-Bogoliubov approaches,both fluctuations and three-body loss are properly treated in our *** find a new type of collapse assisted by fluctuations that amplify the attractive interaction between ***,the calculation of the fluctuated atoms,the entropy,and the second-order correlation function showed that the collapsed gas significantly deviated from a pure state.

关键词： Bose-Einstein condensates collapse fluctuation Hartree-Fock-Bogoliubov formalism

Detumbling strategy based on friction control of dual-arm space robot for capturing tumbling target

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Chinese Journal of Aeronautics 2020年第3期33卷 1093-1106页

作者： Gang CHEN yuqi wang Yifan wang Ji LIANG Long ZHANG Guangtang PAN School of Automation Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing 100094China

The rotational motion of a tumbling target brings great challenges to space robot on successfully capturing the tumbling ***,it is necessary to reduce the target's rotation to a rate at which capture can be accomplished by the space *** this paper,a detumbling strategy based on friction control of dual-arm space robot for capturing tumbling target is *** strategy can reduce the target's rotational velocity while maintaining base attitude stability through the establishment of the rotation attenuation controller and base attitude adjustment *** rotation attenuation controller adopts the multi-space hybrid impedance control method to control the friction *** base attitude adjustment controller applies the dual-arm extended Jacobian matrix to stabilize the base *** main contributions of this paper are as follows:(1)The compliant control method is adopted to achieve a precise friction control,which can reduce the target angular velocity steadily;(2)The dual-arm extended Jacobian matrix is applied to stabilize the base attitude without affecting the target capture task;(3)The detumbling strategy of dualarm space robot is designed considering base attitude stabilization,realizing coordinated planning of the base attitude and the *** strategy is verified by a dual-arm space robot with two 7-DOF(degrees of freedom)*** results show that,target with a rotation velocity of 20(°)/s can be effectively controlled to stop within 30 s,and the final deflection of the base attitude is less than 0.15°without affecting the target capture task,verifying the correctness and effectiveness of the *** to the tumbling target capture task,the control strategy can also be applied to other typical on-orbit operation tasks such as space debris removal and spacecraft maintenance.

关键词： Detumbling strategy Dual-arm space robot Free-floating base Friction control Tumbling target capturing

Novel broad spectral response perovskite solar cells:A review of the current status and advanced strategies for breaking the theoretical limit efficiency

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Journal of Materials Science & Technology 2023年第9期140卷 33-57页

作者： Bin Liu yuqi wang Yanjie Wu Biao Dong Hongwei Song State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

Perovskite solar cells(PSCs)have revolutionized photovoltaic *** power conversion efficiency(PCE)of PSCs has now reached 25.7%,which is comparable to current state-of-the-art silicon-based ***,PSCs can only utilize light of 300-850 nm,resulting in wasted near-infrared(NIR)light,which occupies 45%-50%of entire solar spectrum,which is one of the main reasons limiting the development of *** strategies to broaden NIR spectroscopy to break the theoretical limit efficiency of PSCs have recently attracted extensive *** review firstly outlines theoretical basis for improving the NIR spectroscopy,then systematically summarizes some key strategies and research progress to improve NIR spectroscopy of *** firstly provided a comprehensive overview of historical research experiments on narrow-gap perovskite absorber layers,rare earth up-conversion,tandem devices,and integrated perovskite/organic solar cells and given constructive suggestions for exceeding limit efficiency of ***,based on the development status of PSCs with NIR utilization,the current issues,solutions and future development directions of important aspects to improve NIR utilization of PSCs are systematically *** review lays the foundation for the efficiency of PSCs beyond the Shockley-Queisser limit,and provides a certain development prospect.

关键词： Organic materials Up-conversion materials Perovskite solar cells Tandem cells Integrated perovskite/organic heterojunction solar cells

Tooth Position and Deformation of Flexspline Assembled with Cam in Harmonic Drive Based on Force Analysis

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Chinese Journal of Mechanical Engineering 2021年第6期34卷 385-404页

作者： Yunpeng Yao Xiaoxia Chen Jingzhong Xing Liteng Shi yuqi wang School of Mechanical Engineering Tiangong UniversityTianjin300387China Tianjin City Key Lab of Modern Mechatronics Equipment Technology Tianjin300387China

Deformation of the flexspline is the basis of analyzing tooth trajectory and designing tooth *** the tooth influence on the position of equivalent neutral layer,a piecewise method for calculating the deformation of flexspline assembled with a cam wave generator is presented in this ***,a mechanic model of a ring of uniform thickness in contact with a rigid cam is *** displacements of the ring inside and outside an unknown wrapping angle are determined by the geometric constraints of the cam profile and the equilibrium rela-tionship,***,the wrapping angle is solved according to the boundary *** assembly forces are derived to investigate the circumferential elongation and ***,considering the tooth effects on the neutral layer of flexspline,the tooth is positioned on the equivalent neutral layer,which is the non-elongation layer within one gear pitch but offset from the geometric *** equivalent neutral layer is positioned by the empirical formula of the offset ratio,which is summarized by the orthogonal simulation on finite element models of ***,finite element models of a ring-shaped and a cup-shaped flexspline assembled with elliptical cam are established to verify the effectiveness and accuracy of the piecewise *** results show that,compared with the geometric method,the tooth positioning deviation calculated by the piecewise method can be reduced by about 70%with a more accurate deformation description from the geometric condition and mechanic condition inside and outside the wrapping angle.

关键词： Harmonic drive Deformation calculation Cam wave generator Force analysis Equivalent neutral layer

Identification of Rice Al-responsive Genes by Semi-quantitative Polymerase Chain Reaction using Sulfite Reductase as a Novel Endogenous Control

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Journal of Integrative Plant Biology 2010年第5期52卷 505-514页

作者： Jianjun Zhang Ying Yin yuqi wang Xinxiang Peng Laboratory of Molecular Plant Physiology College of Life Sciences South China Agricultural University Guangzhou 510642 China Key Laboratory of Plant Functional Genomics and Biotechnology Education Department of Guangdong Province College of LifeSciences South China Agricultural University Guangzhou 510642 China Laboratory of Biochemistry and Molecular Biology College of Life Sciences South China Agricultural University Guangzhou 510642 China

Based on the evidence that Al resistance is an inducible process and rice is an Al-resistant crop, identification of Al-responsive genes from rice may help to further clone *** genes in plants. Semi-quantitative and real-time polymerase chain reaction （PCR） is widely applied in gene transcrip- tional analyses, particularly for those genes with low transcript abundance. Normalization with proper endogenous control （EC） genes is critical for these two approaches in terms of reliability and precision. We first noticed that the expression of several commonly-used EC genes was depressed under AI stress, while sulfite reductase gene （SR） was stable throughout the AI treatment. The reliability of SR as an EC gene was further tested by analyzing the expression of a number of genes in response to Al challenge. Except for the consistent results obtained for the four previously-identified genes, nine additional genes were newly defined as Al-responsive in this study. Collectively, our results suggest that SR can be used as a novel EC gene for semi-quantitative and real-time PCR analysis of Al responsive genes, and that activated transport of silicon and stimulated metabolism of carotenoid and terpenoid could be involved in Al resistance in rice plants.

关键词： Rice Beers Aluminium Plants Planting Genes Transport Uses Transcription Strontium

响应面法优化信号分子AI-2合成蛋白LuxS表达条件

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河南师范大学学报（自然科学版） 2025年第1期53卷 136-143,I0009页

作者：李祎韩朔王玉琪秦梦园吴晓敏河南师范大学生命科学学院河南新乡453007

群体感应是一种由自诱导物(autoinducers,AIs)介导的、细菌密度依赖的基因表达调控方式,已经被证实参与细菌多种生理功能的调控.信号分子AI-2介导的LuxS/AI-2型群体感应系统广泛存在于革兰氏阳性和阴性细菌,并备受关注.AI-2的合成依赖... 详细信息

群体感应是一种由自诱导物(autoinducers,AIs)介导的、细菌密度依赖的基因表达调控方式,已经被证实参与细菌多种生理功能的调控.信号分子AI-2介导的LuxS/AI-2型群体感应系统广泛存在于革兰氏阳性和阴性细菌,并备受关注.AI-2的合成依赖于S-核糖同型半胱氨酸酶(LuxS)的催化作用,而LuxS蛋白则是由luxS基因经过转录、翻译得到的.为了探索LuxS蛋白在表达菌株Escherichia coli BL21(DE3)中的最佳表达条件,从而获得较高产量且具有一定的生物活性的LuxS蛋白.首先对LuxS蛋白结构进行预测,确定*** BL21(DE3)作为表达菌株.其次,在单因素优化的基础上,进一步通过响应面法优化LuxS蛋白的表达条件.在菌液浓度OD 600为0.5、诱导温度为37℃、IPTG浓度为0.5 mmol/L、诱导时间为31 h条件下,获得LuxS蛋白的最高表达量.研究成功优化了LuxS蛋白在*** BL21(DE3)中的诱导表达条件,获得了具有生物活性的LuxS蛋白,并在后续的研究中成功合成了具有生物活性的信号分子AI-2,为体外合成AI-2奠定了基础.

关键词：群体感应 AI-2 LuxS蛋白原核表达条件优化

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Rethinking the image feature biases exhibited by deep convolutional neural network models in image recognition

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CAAI Transactions on Intelligence Technology 2022年第4期7卷 721-731页

作者： Dawei Dai Yutang Li yuqi wang Huanan Bao Guoyin wang College of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqingChina

In recent years,convolutional neural networks(CNNs)have been applied successfully in many ***,these deep neural models are still considered as“black box”for most *** of the fundamental issues underlying this problem is understanding which features are most influential in image recognition tasks and how CNNs process these *** is widely believed that CNN models combine low‐level features to form complex shapes until the object can be readily classified,however,several recent studies have argued that texture features are more important than other *** this paper,we assume that the importance of certain features varies depending on specific tasks,that is,specific tasks exhibit feature *** designed two classification tasks based on human intuition to train deep neural models to identify the anticipated *** designed experiments comprising many tasks to test these biases in the Res Net and Dense Net *** the results,we conclude that(1)the combined effect of certain features is typically far more influential than any single feature;(2)in different tasks,neural models can perform different biases,that is,we can design a specific task to make a neural model biased towards a specific anticipated feature.

关键词： CNNs features understandable models