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Intelligent Optimization Methods for the Design of an Overhead Travelling Crane

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 187-196页

作者： QU Xiaogang XU gening FAN Xiaoning BI Xiaoheng School of Mechanical & Electronical Engineering Lanzhou University of Technology School of Mechanical Engineering Taiyuan University of Science and Technology

In design optimization of crane metal structures, present approaches are based on simple models and mixed variables, which are difficult to use in practice and usually lead to failure of optimized results for rounding variables. Crane metal structure optimal design（CMSOD） belongs to a constrained nonlinear optimization problem with discrete variables. A novel algorithm combining ant colony algorithm with a mutation-based local search（ACAM） is developed and used for a real CMSOD for the first time. In the algorithm model, the encoded mode of continuous array elements is introduced. This not only avoids the need to round optimization design variables during mixed variable optimization, but also facilitates the construction of heuristic information, and the storage and update of the ant colony pheromone. Together with the proposed ACAM, a genetic algorithm（GA） and particle swarm optimization（PSO） are used to optimize the metal structure of a crane. The optimization results show that the convergence speed of ACAM is approximately 20% of that of the GA and around 11% of that of the PSO. The objective function value given by ACAM is 22.23% less than the practical design value, a reduction of 16.42% over the GA and 3.27% over the PSO. The developed ACAM is an effective intelligent method for CMSOD and superior to other methods.

关键词： crane metal structure design optimization continuous array element encoded model ant colony optimization particle swarm optimization genetic algorithm

Fatigue Life Evaluation Method for Foundry Crane Metal Structure Considering Load Dynamic Response and Crack Closure Effect

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Computer Modeling in Engineering & Sciences 2020年第2期122卷 525-553页

作者： Qing Dong Bin He gening Xu School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuanChina.

To compensate for the shortcomings of quasi-static law in anti-fatigue analysis of foundry crane metal structures,the fatigue life evaluation method of foundry crane metal structure considering load dynamic response and crack closure effect is *** line with the theory of mechanical vibration,a dynamic model of crane structure during the working cycle is constructed,and dynamic coefficients under diverse actions are *** models of the internal force dynamic change process of dangerous cross-sections and a simulation model of first principal stress-time history are established by using the steel structure design criteria,which is utilised to extract the change of first principal stress of danger points over ***,the double-parameter stress spectrum is obtained by the rain flow counting *** fatigue life calculation formula is corrected by introducing a crack closure parameter that can be calculated by the stress ratio and the effective stress *** the finite element model imported into ***,crack propagation analysis is performed by the growth method in the fatigue integration module *** the metal structure of a 100/40t-28.5m foundry crane with track offset as an example,the accuracy of calculation results and the feasibility and applicability of the proposed method are verified by theoretical calculation and finite element simulation,which provide a theoretical basis for improvement of the fatigue resistance design of foundry cranes.

关键词： Metal structure of foundry crane load dynamic effect crack closure effect crack propagation fatigue life.

Methodology to Estimate Remaining Service Life of Steel Structure by Possibilistic Reliability Theory

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Chinese Journal of Mechanical Engineering 2010年第6期23卷 780-787页

作者： XU gening YANG Ruigang ZHOU Ke FAN Xiaoning School of Machinery and Electronics Engineering Taiyuan University of Science and Technology Taiyuan 030024 China School of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology Taiyuan 030024 China

Steel structure system of crane deteriorates over time due to environmental effects, material fatigue, and overloading. System structural reliability and remaining service life assessment methods are developed during the few decades. But until now estimating remaining service life methods of crane steel system by reliability theory begin to develop. Safety assessment of existing steel structure system requires the development of a methodology that allows for an accurate evaluation of reliability and prediction of the remaining life. Steel structures are the supporting elements in the special equipment such as hoisting machinery. Structure reliability and remaining service life safe assessment are important for steel structures. For finding the reason which caused the failure modes （such as fatigue strength failure, stiffness failure and stability failure）, incremental loading method based on possibilistic reliability is applied into dynamic structure failure path research. Through reliability analyzing and calculating for crane, it is demonstrated that fatigue damage is the most common failure mode. Fuzzy fatigue damage accumulation theory is used for basis theory and Paris-Eadogan equations are used for mathematical modeling. All fatigue parameter values of the welding box girder of bridge cranes are determined and fatigue remaining life formulas are deduced. After field test and collecting working parameters of numerous cranes, typical fatigue load spectrum was compiled for the dangerous point of box girders used in the area. Fatigue remaining life is assessed for different types and lifting capacities. Safety for steel structure system of bridge crane is assessed by two quantitative indexs： reliability and remaining life. Therefore, the evaluation means is more comprehensive and reasonable. The example shows that the two quantitative indexs are mutually correlated. Through analyzing the 120 t-22.5 m bridge crane of a certain enterprise, a new methodology to estim

关键词： steel structure system fuzzy fatigue damage possibilistic reliability

Research on Adaptive TSSA-HKRVM Model for Regression Prediction of Crane Load Spectrum

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2345-2370页

作者： Dong Qing Qi Song Shuangyun Huang gening Xu College of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan030024China Zhuzhou Tianqiao Crane Co. Ltd.Zhuzhou412001China

For the randomness of crane working load leading to the decrease of load spectrum prediction accuracy with time,an adaptive TSSA-HKRVM model for crane load spectrum regression prediction is *** heterogeneous kernel relevance vector machine model(HKRVM)with comprehensive expression ability is established using the complementary advantages of various kernel *** combination strategy consisting of refraction reverse learning,golden sine,and Cauchy mutation+logistic chaotic perturbation is introduced to form a multi-strategy improved sparrow algorithm(TSSA),thus optimizing the relevant parameters of *** adaptive updatingmechanismof the heterogeneous kernel RVMmodel under themulti-strategy improved sparrow algorithm(TSSA-HKMRVM)is defined by the sliding window design *** on the sample data of the measured load spectrum,the trained adaptive TSSA-HKRVMmodel is employed to complete the prediction of the crane equivalent load *** this method toQD20/10 t×43m×12mgeneral bridge crane,the results show that:compared with other prediction models,although the complexity of the adaptive TSSA-HKRVMmodel is relatively high,the prediction accuracy of the load spectrum under long periods has been effectively improved,and the completeness of the load information during thewhole life cycle is relatively higher,with better applicability.

关键词： Heterogeneous kernel function RVM TSSA adaptive update mechanism equivalent load spectrum

HYPERSTATIC STRUCTURE MAPPING MODEL BUILDING AND OPTIMIZING DESIGN

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Chinese Journal of Mechanical Engineering 2007年第1期20卷 55-59页

作者： XU gening GAO Youshan ZHANG Xueliang YANG Ruigang College of Mechanical Electronic Engineenng Taiyuan University of Science and Technology Taiyuan 030024 China Department of Automotive Engineenng Beihang University Beijing 100083 China College of Mechanical Eleclronic Engineenng Taiyuan University of Science and Technology Taiyuan 030024 China

Hyperstatic structure plane model being built by structural mechanics is studied. Space model precisely reflected in real stress of the structure is built by finite element method （FEM） analysis commerce software. Mapping model of complex structure system is set up, with convenient calculation just as in plane model and comprehensive information as in space model. Plane model and space model are calculated under the same working condition. Plane model modular construction inner force is considered as input data; Space model modular construction inner force is considered as output data. Thus specimen is built on input data and output dam. Character and affiliation are extracted through training specimen, with the employment of nonlinear mapping capability of the artificial neural network. Mapping model with interpolation and extrpolation is gained, laying the foundation for optimum design. The steel structure of high-layer parking system （SSHLPS） is calculated as an instance. A three-layer back-propagation （BP） net including one hidden layer is constructed with nine input nodes and eight output nodes for a five-layer SSHLPS. The three-layer structure optimization result through the mapping model interpolation contrasts with integrity re-analysis, and seven layers structure through the mapping model extrpulation contrasts with integrity re-analysis. Any layer SSHLPS among 1-8 can be calculated with much accuracy. Amount of calculation can also be reduced if it is appfied into the same topological structure, with reduced distortion and assured precision.

关键词： Plane model - Space model Artificial neural networks Mapping model Optimum design

Load Reduction Test Method of Similarity Theory and BP Neural Networks of Large Cranes

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 145-151页

作者： YANG Ruigang duAN Zhibin LU Yi WANG Lei XU gening School of Mechanical Engineering Taiyuan University of Science and Technology

Static load tests are an important means of supervising and detecting a crane＇s lift capacity. due to space restrictions, however, there are difficulties and potential danger when testing large bridge cranes. To solve the loading problems of large-tonnage cranes during testing, an equivalency test is proposed based on the similarity theory and BP neural networks. The maximum stress and displacement of a large bridge crane is tested in small loads, combined with the training neural network of a similar structure crane through stress and displacement data which is collected by a physics simulation progressively loaded to a static load test load within the material scope of work. The maximum stress and displacement of a crane under a static load test load can be predicted through the relationship of stress, displacement, and load. By measuring the stress and displacement of small tonnage weights, the stress and displacement of large loads can be predicted, such as the maximum load capacity, which is 1.25 times the rated capacity. Experimental study shows that the load reduction test method can reflect the lift capacity of large bridge cranes. The load shedding predictive analysis for Sanxia 1200 t bridge crane test data indicates that when the load is 1.25 times the rated lifting capacity, the predicted displacement and actual displacement error is zero. The method solves the problem that lifting capacities are difficult to obtain and testing accidents are easily possible when 1.25 times related weight loads are tested for large tonnage cranes.

关键词： similarity theory BP neural network large bridge crane load reduction equivalent test method

Selection of candidates for surgery as local therapy among early-stage small cell lung cancer patients: a population-based analysis

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Cancer Communications 2018年第1期38卷 63-73页

作者： Kaiqi Jin Kaixuan Zhang Feng Zhou Jie Dai Peng Zhang gening Jiang Department of Thoracic Surgery Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityNo.507 Zhengmin RoadShanghai 200433P.R.China

Background:Surgery and radiotherapy are considered local therapies for small cell lung cancer(SCLC).The present study aimed to select candidates for surgery as local therapy among patients with stage I or II SCLC,based on the eighth edition of the TNM classification for lung ***:Patients diagnosed with SCLC between 2004 and 2013 were selected from the Surveillance,Epidemiology,And End Results *** TNM stage of SCLC in these patients was re-classified according to the eighth edition of the TNM classification for lung *** with stage I or II SCLC were included in the present *** survival(OS)and lung cancer-specific survival(LCSS)were separately compared in the different TNM stages between patients who received surgery and radiotherapy as local *** analysis was applied to evaluate multi-ple factors associated with ***:Among the 2129 patients included in the present study,387(18.2%)received surgery,1032(48.5%)under-went radiotherapy as local therapy,154(7.2%)underwent surgery and radiotherapy,and 556(26.1%)did not undergo either surgery or *** patients with T1-2N0(tumor size≤50 mm without positive lymph nodes)dis-ease,patients who underwent surgery had higher 5-year OS and LCSS rates than patients who received radiotherapy(T1N0:46.0%vs.23.8%,P<0.001,and 58.4%vs.36.4%,P<0.001,respectively;T2N0:42.6%vs.24.7%,P=0.004,and 48.8%vs.31.3%,P=0.011,respectively).Multivariate analysis results revealed that surgery was associated with low risk of ***,among T3N0 or T1-2N1(stage IIB)SCLC patients,patients who underwent surgery did not have higher 5-year OS and LCSS rates than patients who received radiotherapy(T3N0:16.2%vs.26.5%,P=0.085,and 28.7%vs.30.9%,P=0.372,respectively;T1-2N1:20.3%vs.29.0%,P=0.146,and 25.6%vs.35.5%,P=0.064,respectively).Conclusions:Based on the assumption that the overwhelming majority of stage I or II SCLC patients who underwent surgery or radiotherapy also received

关键词： Small cell lung cancer Surgery Local therapy Radiotherapy

Characterization and properties of a Sr2Si5N8:Eu^2+-based light-conversion agricultural film

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Journal of Rare Earths 2020年第5期38卷 539-545页

作者： Weibin Wu Zhenbang Zhang Riyue Dong gening Xie Jianxian Zhou Kejue Wu Haonan Zhang Qianpei Cai Bingfu Lei College of Engineering South China Agricultural UniversityGuangzhou 510642China Guangdong Laboratory of Lingnan Mordern Agriculture Guangzhou 510642China College of Materials and Energy South China Agricultural UniversityGuangzhou 510642China Guangdong Provincial Engineering Technology Research Center for Optical Agriculture Guangzhou 510642China

In this paper,the fracture surfaces of a light-conversion film were observed using a scanning electron microscope(SEM),and then,the fluorescence spectra and mechanical properties of the film were *** SEM results show that the average diameter of the light conversion agent is 500 *** results of the mechanical properties tests show that the tensile strengths of light-conversion film increase from9.86 to 12.16 MPa and that the strain at breakage increases from 2.37%to 2.75%.In addition,the application effects of the light-co nversion film were *** results indicate that plant height,length of the maximum leaf,width of the maximum leaf and breadth of the plants increase by 24.43%,15.30%,15.60%and 19.07%,*** quality of Chinese flowering cabbages treated with the lightconversion film is superior,including a 9.09%increase in the soluble protein content,a 21.27%increase in the polyphenol content,and a 19.15%increase in the soluble sugar *** on these results,light-conversion films can be applied in agricultural production.

关键词： Light-conversion film Sr2Si5N8%Eu^2+phosphor Biomass Photosynthetic pigment content Rare earths

Outcomes of patients awaiting lung transplantation after the implementation of donation after brain death at a single Chinese center

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Frontiers of Medicine 2022年第5期16卷 760-765页

作者： Yuling Yang Xinnan Xu Ming Liu Yanfeng Zhao Yongmei Yu Xiaogang Liu Chang Chen gening Jiang Wenxin He Department of Thoracic Surgery Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityShanghai 200092China Department of Cardiothoracic Surgery Zhangzhou Affiliated Hospital of Fujian Medical UniversityZhangzhou 363000China

oluntary contribution has become the only source of donor lungs in China since *** elaborate the outcomes of patients awaiting lung transplantation(LTx)after the implementation of donation after brain death,we performed a retrospective study that encompassed 205 patients with end-stage lung disease who registered for LTx at Shanghai Pulmonary Hospital from January 1,2015 to January 1,2021.A total of 180 patients were enrolled in the *** median waiting time was 1.25 *** lung disease(ILD)(103/180,57.2%)and chronic obstructive pulmonary disease(COPD)(56/180,31.1%)were the most common diseases in our study *** mean pulmonary artery pressure(mPAP)of patients in the died-waiting group was higher than that of the survivors(53.29+21.71 mmHg vs.42.11+18.58 mmHg,P-0.002).The mortality of patients with ILD(34/103,33.00%)was nearly twice that of patients with COPD(10/56,17.86%)while awaiting LTx(P-0.041).In the died-waiting group,patients with ILD had a shorter median waiting time than patients with COPD after being listed(0.865 months vs.4.720 months,P-0.030).ILD as primary disease and mPAP>35 mmHg were two significant independent risk factors for waitlist mortality,with hazard ratios(HR)of 3.483(95%CI 1.311-9.111;P-0.011)and 3.500(95%CI 1.435-8.536;P=0.006).Hence,LTx is more urgently needed in patients with ILD and pulmonary hypertension.

关键词： lung transplantation donation after brain death waitlist