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Dynamical analysis and performance evaluation of a biped robot under multi-source random disturbances

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Acta Mechanica Sinica 2014年第6期30卷 983-994页

作者： Chun-Biao Gan Chang-Tao Ding shi-xi yang The State Key Laboratory of Fluid Power Transmission and Control Department of Mechanical EngineeringZhejiang University

During bipedal walking,it is critical to detect and adjust the robot postures by feedback control to maintain its normal state amidst multi-source random disturbances arising from some unavoidable uncertain *** radical basis function（RBF）neural network model of a five-link biped robot is established,and two certain disturbances and a randomly uncertain disturbance are then mixed with the optimal torques in the network model to study the performance of the biped robot by several evaluation indices and a specific Poincar′e *** contrast with the simulations,the response varies as desired under optimal inputting while the output is fluctuating in the situation of disturbance *** results from noise inputting also show that the dynamics of the robot is less sensitive to the disturbance of knee joint input of the swing leg than those of the other three joints,the response errors of the biped will be increasing with higher disturbance levels,and especially there are larger output fluctuations in the knee and hip joints of the swing leg.

关键词： Biped robot Multi-source random disturbances Sensitive parameters RBF neural network Taguchi method Performance evaluation

Input torque sensitivity to uncertain parameters in biped robot

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Acta Mechanica Sinica 2013年第3期29卷 452-461页

作者： Chang-Tao Ding shi-xi yang Chun-Biao Gan Department of Mechanical Engineering Zhejiang University

Input torque is the main power to maintain bipedal walking of robot, and can be calculated from trajectory planning and dynamic modeling on biped robot. During bipedal walking, the input torque is usually required to be adjusted due to some uncertain parameters arising from objective or subjective factors in the dynamical model to maintain the pre-planned stable trajectory. Here, a planar 5-link biped robot is used as an illustrating example to investigate the effects of uncertain parameters on the input torques. Kine-matic equations of the biped robot are firstly established by the third-order spline curves based on the trajectory planning method, and the dynamic modeling is accomplished by taking both the certain and uncertain parameters into account. Next, several evaluation indices on input torques are intro-duced to perform sensitivity analysis of the input torque with respect to the uncertain parameters. Finally, based on the Monte Carlo simulation, the values of evaluation indices on input torques are presented, from which all the robot param-eters are classified into three categories, i.e., strongly sensi-tive, sensitive and almost insensitive parameters.

关键词： Biped robot · Uncertain parameter · Trajectory planning · Input torque · Sensitivity

Arabidopsis MSBP1 Is Activated by HY5 and HYH and Is Involved in Photomorphogenesis and Brassinosteroid Sensitivity Regulation

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Molecular Plant 2011年第6期4卷 1092-1104页

作者： Qiu-Ming shi xi yang Li Song Hong-Wei Xue National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 300 Fenglin Road 200032 Shanghai PR China

Membrane Steroid Binding Protein 1 （MSBP1） can bind steroids in vitro and negatively regulates brassinosteroid （BR） signaling, as well as cell elongation and expansion. Detailed analysis of the MSBP1 expression pattern based on quantitative real-time RT-PCR and promoter-GUS fusion studies revealed that MSBP1 expression in hypocotyls is stimulated by various light conditions, Interestingly, MSBP1 expression is greatly suppressed in hyS, hyh, or hy5hyh mutants but enhanced in cop1 mutants, Further analysis employing a yeast one-hybrid assay, an electrophoretic mobility shift assay （EMSA）, and a Chromatin IP （CHIP） assay confirmed the direct binding of Long Hypocotyl 5 （HY5） and HY5 Homolog （HYH） to the promoter region of MSBP1, indicating that MSBP1 is involved in light-regulated hypocotyl growth by serving as a direct target for HY5 and HYH. In addition, hy5 and hy5 hyh mutants show altered BR responses to light, which is consistent with the suppressed expression of MSBP1 in these mutants. These results suggest that light triggers MSBP1 ex- pression through direct binding to and activation by HY5 and HYH, thereby inhibiting hypocotyl elongation. The findings also provide informative clues regarding the mechanisms for the negative regulation of BR sensitivity and photomorpho- genesis during the dark-light transition.

关键词： MSBP1 HY5 HYH photomorphogenesis BR signaling.

双跨转子的随机不确定性非参数建模与可靠性分析（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第3期19卷 189-202页

作者： Chun-biao GAN Yue-hua WANG shi-xi yang State Key Laboratory of Fluid Power and Mechatronic Systems College of Mechanical Engineering Zhejiang University Hangzhou 310027 China Key Laboratory of Advanced Manufacturing Technology of Zhejiang Province College of Mechanical Engineering Zhejiang University Hangzhou 310027 China

目的:旋转机械由于工作环境复杂,在运行过程中会不可避免地受到各种不确定性因素的影响,从而引发转子系统的异常振动。因此,迫切需要对系统工作状态开展可靠性分析。本文将外部扰动不确定性与模型不确定性考虑在内,旨在建立转子系统运... 详细信息

目的:旋转机械由于工作环境复杂,在运行过程中会不可避免地受到各种不确定性因素的影响,从而引发转子系统的异常振动。因此,迫切需要对系统工作状态开展可靠性分析。本文将外部扰动不确定性与模型不确定性考虑在内,旨在建立转子系统运行状态的可靠性评估指标,丰富转子动力学理论体系,为工程应用提供参考。创新点:1.采用非参数法进行建模,能够将外部扰动不确定性与模型不确定性同时包含在内;2.在非参数建模基础上,结合响应谱分析法进行可靠性计算,可避免对系统先验知识的需求并降低计算过程的复杂性;3.将短周期预测理论扩展应用于可靠性分析验证。方法:1.借助非参数法建立转子系统的随机不确定性模型;2.结合响应谱分析法推导出系统可靠性指标计算式;3.采用短周期预测方法对模拟数据统计指标进行计算与验证。结论:1.本方法可用于评估大型复杂旋转机械系统的可靠性,尤其对于服役时间较长导致系统参数出现不确定性变化的情形;2.本研究结果可为大型复杂旋转机械的设计、运行和控制提供理论基础,同时也可以为其他类型机械设备的可靠性分析和预测方法提供参考。

关键词：随机不确定性非参数建模可靠性响应谱分析

Tranylcypromine upregulates Sestrin 2 expression to ameliorate NLRP3-related noise-induced hearing loss

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Neural Regeneration Research 2025年第5期20卷 1483-1494页

作者： xihang Chen Zhifeng Chen Menghua Li Weiwei Guo Shuolong Yuan Liangwei Xu Chang Lin xi shi Wei Chen shiming yang Senior Department of Otolaryngology Head and Neck Surgery Chinese PLA General HospitalChinese PLA Medical SchoolBeijingChina State Key Laboratory of Hearing and Balance Science BeijingChina National Clinical Research Center for Otolaryngologic Diseases BeijingChina Key Laboratory of Hearing Science Ministry of EducationBeijingChina Beijing Key Laboratory of Hearing Impairment Prevention and Treatment BeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Otolaryngology Head and Neck Surgery The 940th Hospital of Joint Logistics Support Force of Chinese PLALanzhouGansu ProvinceChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikouHainan ProvinceChina Academician Workstation of Hainan University School of Pharmaceutical SciencesYazhou BaySanyaHainan ProvinceChina

Noise-induced hearing loss is the primary non-genetic factor contributing to auditory ***,there are currently no effective pharmacological interventions for patients with noise-induced hearing ***,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory *** established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 *** found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with *** noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with *** findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell ***,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy *** treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)*** conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing *** findings suggest that inhibiting lysine-specific demethylase 1 is a

关键词： 4-hydroxynonenal apoptosis autophagy cleaved caspase-3 inflammation NOD-like receptor family pyrin domain-containing 3(NLRP3) noise-induced hearing loss oxidative stress Sestrin2 tranylcypromine

Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 65-78页

作者： shi Yuqiong LI Jingyi ZHANG yang LI Li Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F Uni-versityYangling 712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China Chongqing Key Laboratory of Public Big Data Security Technology Chongqing 401420China Chongqing College of Mobile Communication Chongqing 401520China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityKowloonHung HomHong KongChina

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive *** this study,505 groups of data were collected,and a new database of compressive strength of PFGC was *** order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative *** five machine learning models all showed good compressive strength prediction performance on *** them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,*** R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,*** two models have high prediction accuracy and outstanding generalization *** order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 *** 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide *** temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement *** importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.

关键词： machine learning pure fly ash geopolymer compressive strength feature perception

Revealing and predicting the long-term biomechanical response of orthokeratology by developing a patient-specific computational model

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 156-168页

作者： Yifeng Li Zhuoran yang Ziming Yan Huibin shi Zhanli Liu Kaijie Wang Department of Engineering Mechanics School of Aerospace Engineering Tsinghua University Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology & Visual Sciences Key Lab

Orthokeratology(OK) is widely used for effective myopia correction and control. However, the incomplete understanding of its biomechanical mechanisms makes OK lens fitting rely heavily on clinician judgment, complicating accurate predictions of treatment outcomes. In this paper, we performed clinical experiments and numerical analysis to study corneal deformation modes and long-term changes in central corneal thickness. Clinical experiments were conducted on 194 Chinese myopic patients under OK treatment for 3 months. Based on the experimental data, a patient-specific computational biomechanical model for OK was established and validated. Specifically, the anisotropic mechanical properties of the cornea were incorporated into the model to describe the significant difference between its shear modulus(29.5 kPa) and tensile modulus(768.4 kPa). Additionally, a viscohyperelastic material model with a prolonged corneal relaxation time of 5.6 h was developed to capture the long-term deformation response. The results show that corneal thickness reduction in OK is primarily due to out-of-plane shear deformation,influenced by the cornea's low shear resistance. Modeling the extended corneal relaxation time is crucial for predicting long-term biomechanical responses. The computational model effectively captures long-term changes in central corneal thickness, potentially improving OK lens fitting accuracy.

关键词： orthokeratology computational biomechanical model long-term viscoelasticity myopia correction

Mechanical Properties of Railway High-strength Manufactured Sand Concrete: Typical Lithology, Stone Powder Content and Strength Grade

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 194-203页

作者： WANG Zhen LI Huajian HUANG Fali yang Zhiqiang WEN Jiaxin shi Henan Railway Engineering Research Institute China Academy of Railway Science Corporation LimitedBeijing 100081China State Key Laboratory for Track Technology of High-Speed Railway Beijing 100081China

In order to achieve the large-scale application of manufactured sand in railway high-strength concrete structure,a series of high-strength manufactured sand concrete(HMC)are prepared by taking the manufactured sand lithology(tuff,limestone,basalt,granite),stone powder content(0,5%,10%,15%)and concrete strength grade(C60,C80,C100)as *** evolution of mechanical properties of HMC and the correlation between cubic compressive strength and other mechanical properties are *** to river sand,manufactured sand enhances the cubic compressive strength,axial compressive strength and elastic modulus of concrete,while its potential microcracks weaken the flexural strength and splitting tensile strength of *** powder content displays both positive and negative effects on mechanical properties of HMC,and the stone powder content is suggested to be less than 10%.The empirical formulas between cubic compressive strength and other mechanical properties are proposed.

关键词： manufactured sand concrete railway mechanical property lithology stone powder content

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盐穴储气库泥岩夹层渗透性测试新方法

岩土力学 2017年第8期38卷 2241-2248页

作者：尹洪武马洪岭施锡林杨春和中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071 中国科学院大学北京100049

金坛盐穴储气库现场压井试验发现某泥岩夹层密封性欠佳,可能影响储气库运行的密闭性,钻井取芯情况表明,该夹层易破碎,难以开展系统的渗透性测试试验。针对该问题,提出了一种测试易碎泥岩夹层渗透率的新方法,将泥岩夹层岩芯浇筑在环氧树... 详细信息

金坛盐穴储气库现场压井试验发现某泥岩夹层密封性欠佳,可能影响储气库运行的密闭性,钻井取芯情况表明,该夹层易破碎,难以开展系统的渗透性测试试验。针对该问题,提出了一种测试易碎泥岩夹层渗透率的新方法,将泥岩夹层岩芯浇筑在环氧树脂中,通过切割打磨等工序制备出符合渗透试验要求的标准试样。为了观测泥岩夹层岩芯与环氧树脂的胶结情况,对人工合成试样进行了镀金电镜扫描试验,发现交界面孔隙较岩石孔隙小、胶结良好,说明夹层岩芯是人工合成试样中的主要渗透通道。利用稳态法对人工合成试样进行渗透率测试,测试结果与其他学者的测试结果吻合,证实了该方法的可靠性。同时开展了理论分析,结果表明,浇筑式方法测得的渗透率与理论结果相符,从理论上进一步证实了其可行性。文中所述的泥岩夹层渗透性测试方法,对测试不规则破碎岩芯的渗透率具有一定参考意义。

关键词：盐穴储气库易碎泥岩夹层环氧树脂人工合成试样渗透率测试