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Crashworthiness Analysis on Alternative Square Honeycomb Structure under Axial Loading

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Chinese Journal of Mechanical Engineering 2013年第4期26卷 784-792页

作者： LI Meng DENG Zongquan GUO Hongwei LIU Rongqiang ding beichen State Key Laboratory of Robotics and System Harbin Institute of Technology

Hexagonal metal honeycomb is widely used in energy absorption field for its special construction. However, many other metal honeycomb structures also show good energy absorption characteristics. Currently, most of the researches focus on hexagonal honeycomb, while few are performed into different honeycomb structures. Therefore, a new alternative square honeycomb is developed to expand the non-hexagonal metal honeycomb applications in the energy absorption fields with the aim of designing low mass and low volume energy absorbers. The finite element model of alternative square honeycomb is built to analyze its specific energy absorption property. As the diversity of honeycomb structure, the parameterized metal honeycomb finite element analysis program is conducted based on PCL language. That program can automatically create finite element model. Numerical results show that with the same foil thickness and cell length of metal honeycomb, the alternative square has better specific energy absorption than hexagonal honeycomb. Using response surface method, the mathematical formulas of honeycomb crashworthiness properties are obtained and optimization is done to get the maximum specific energy absorption property honeycomb. Optimal results demonstrate that to absorb same energy, alternative square honeycomb can save 10% volume of buffer structure than hexagonal honeycomb can do. This research is significant in providing technical support in the extended application of different honeycomb used as crashworthiness structures, and is absolutely essential in low volume and low mass energy absorber design.

关键词： crashworthiness alternative square honeycomb energy-absorption characteristic response surface methodology numerical simulation

Core Loss Effect Modeling and Compensation for Improved MTPA Control of PMSM Drive under High-speed Conditions

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CES Transactions on Electrical Machines and Systems 2024年第4期8卷 436-446页

作者： Yuting Lu beichen ding Kaide Huang Guodong Feng IEEE School of Intelligent Systems Engineering Sun Yat-sen UniversityShenzhenChina School of Advanced Manufacturing Sun Yat-sen UniversityShenzhenChina School of Mathematics and Big Data Foshan UniversityFoshanChina

For permanent magnet synchronous machines(PMSMs),accurate machine model is critical for high performance maximum torque per ampere(MTPA)***,as motor speed increases,the nonlinearity such as core loss effect will affect the accuracy of machine model and thus the performance of online MTPA *** paper firstly investigates the performance of the model based MTPA control under different motor speeds through modeling,simulation and experiments,which indicates that the accuracy of MTPA control is greatly reduced especially under high-speeds due to machine ***,this paper proposes an efficient nonlinearity compensation model based on polynomial fitting to model and compensate the MTPA error as motor speed *** both core loss and magnetic saturation effects,the compensation model is a nonlinear polynomial of speed and stator *** obtain the fitting data,a derivative modeling method is proposed to compute the actual and detected MTPA angles under different speeds,in which the derivative model of torque to current ratio is fitted and the MTPA angle is obtained by setting the derivative model to *** proposed compensation model is both computation effective and easy to use for MTPA control,as it computes the compensation term that can be directly combined to other model-based *** proposed model is evaluated with experiments and comparisons on a test motor to show the performance improvement.

关键词： Permanent magnet synchronous machine Core loss Magnetic saturation Maximum torque per ampere(MTPA)

Permanent Magnet Temperature Estimation for PMSMs Using Virtual Position-offset Injection

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 51-60页

作者： beichen ding Yuting Lu Kaide Huang Guodong Feng Chunyan Lai IEEE the School of Intelligent Systems Engineering Sun Yat-sen UniversityShenzhen 518107China the Fosan University Foshan 528225China the Department of Electrical and Computer Engineering Concordia UniversityQCCanada

This paper proposes a virtual position-offset injection based permanent magnet temperature estimation approach for permanent magnet synchronous machines(PMSMs). The concept of virtual position-offset injection is mathematically transforming the machine model to a virtual frame with a position-offset. The virtual frame temperature estimation model is derived to calculate the permanent magnet temperature(PMT) directly from the measurements with computation efficiency. The estimation model involves a combined inductance term, which can simplify the establishment of saturation compensation model with less measurements. Moreover, resistance and inverter distorted terms are cancelled in the estimation model, which can improve the robustness to the winding temperature rise and inverter distortion. The proposed approach can achieve simplified computation in temperature estimation and reduced memory usage in saturation compensation. While existing model-based approaches could be affected by either the need of resistance and inverter information or complex saturation compensation. Experiments are conducted on the test machine to verify the proposed approach under various operating conditions.

关键词： PMSM Magnet temperature estimation Virtual position offset injection Inverter nonlinearity

Metabolomics analysis for skin ulceration syndrome of Apostichopus japonicus based on UPLC/Q-TOF MS

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Journal of Oceanology and Limnology 2021年第4期39卷 1559-1569页

作者： Yang ZHANG Youquan WANG Xiaoyu LIU beichen ding Yi SUN Yaqing CHANG Jun ding Key Laboratory of Mariculture&Stock Enhancement in North China’s Sea Ministry of Agriculture and Rural Aff airsDalian Ocean UniversityDalian 116023China

Skin ulceration syndrome(SUS)is the main diseases aff ected the development of sea cucumber(Apostichopus japonicus)culture *** better observe the changes in the sea cucumber *** with SUS and understand the pathogenesis of the disease,activities of superoxide dismutase(SOD),catalase(CAT),and level of malondialdehyde(MDA)in coelomic fluid were detected using the Assay Kit and metabolites in the body wall were assessed using ultra-performance liquid chromatography and quadrupole-time of flight mass *** results indicated that level of MDA was increased during SUS compared with healthy individuals(P1 and P<0.1).Pathway enrichment analysis indicated most enrichment of KEGG pathways were mainly related to energy metabolism,immunity,and osmoregulation such as ABC transporters,glycine,serine and threonine metabolism,tryptophan metabolism and neuroactive ligand-receptor *** study reflected the difference in enzyme activity and metabolites between *** with SUS and those without,which will provide reference data for investigating SUS.

关键词： Apostichopus japonicus skin ulceration syndrome(SUS) metabolome differential metabolites

Molecular characterization and expression of the SiUCP2 gene in sea urchin Strongylocentrotus intermedius

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Journal of Oceanology and Limnology 2021年第4期39卷 1523-1537页

作者： Lingshu HAN Zijiao QUAN Bing HAN beichen ding Xiaofang HUANG Heng WANG Yaqing CHANG Jun ding Key Laboratory of Mariculture&Stock Enhancement in North China's Sea Ministry of Agriculture and Rural Aff airsDalian Ocean UniversityDalian 116023China

Uncoupling protein 2 (UCP2) is a proton transporter located in the inner mitochondrial membrane, and inhibits the formation of adenosine triphosphate and reactive oxygen species by uncoupling oxidative phosphorylation. To provide a theoretical basis for the role of SiUCP2 in lipid metabolism, a 2 341-bp full-length cDNA of SiUCP2 from sea urchin Strongylocentrotus intermedius , which encodes 323 amino acids (predicted MW 36.11 kDa) was obtained, and the structure and function of the SiUCP2 gene and its expression at the mRNA and protein level were studied. SiUCP2 had high homology with UCP2 of other species. Expression of SiUCP2 was detected in the order of tube feet > gonads > coelomocytes > intestines. The expression level was the highest in prismatic larvae and lowest in the two-cell stage. Moreover, using in-situ hybridization, we found that SiUCP2 protein was expressed in the gonads and intestine. This study provided a theoretical basis for subsequent studies on the role of SiUCP2 and its regulatory mechanism in lipid metabolism, and for the improvement of gonad quality to obtain a higher economic value from sea urchins.

关键词： Strongylocentrotus intermedius SiUCP2 gene cloning lipid metabolism in-situ hybridization western blot

Nonlinearity Estimation and Compensation for Accurate PMSM Modeling and Voltage Prediction

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CES Transactions on Electrical Machines and Systems 2024年第4期8卷 394-403页

作者： beichen ding Yuting Lu Chunyan Lai Weiwen Peng Kaide Huang Guodong Feng IEEE School of Advanced Manufacturing Sun Yat-sen UniversityShenzhen 510275China School of Intelligent Systems Engineering Sun Yat-sen UniversityShenzhen 510275China Department of Electrical and Computer Engineering Concordia UniversityMontrealCanada School of Mathematics and Big Data Foshan UniversityFoshan 528000China

For permanent magnet synchronous machine(PMSM),the machine model is critical to predict the operating states for motor control,which,however,can be greatly affected by system ***,this paper investigates accurate machine modeling for control and parameter *** the proposed approach,the PMSM model with saturated inductances is used as the base model,and this paper investigates modeling and compensation of the offsets to the base model due to system nonlinearities such as saturation and core loss effects for accurate machine modeling and voltage ***,the offsets to the base model are modeled using nonlinear functions with variable coefficients to compensate saturation and core loss effect,which can achieve better accuracy without changing the model structure.A differential estimation model is derived to estimate the model coefficients from a small amount of measurements with simplified ***,the model offset calculation is both computation and memory efficient with simplified *** contribution is to improve the machine model accuracy and achieve precise voltage prediction for practical ***,comparisons and the application to temperature estimation are conducted on a test interior PMSM to validate the proposed approach.

关键词： Core loss Differential modeling Multiparameter estimation PMSM

Comparison of the oncological,perioperative and functional outcomes of partial nephrectomy versus radical nephrectomy for clinical T1b renal cell carcinoma:A systematic review and metaanalysis of retrospective studies

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Asian Journal of Urology 2021年第1期8卷 117-125页

作者： Yucong Zhang Gongwei Long Haojie Shang beichen ding Guoliang Sun Wei Ouyang Man Liu Yuan Chen Heng Li Hua Xu Zhangqun Ye Department of Urology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Hubei Institute of Urology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Department of Geriatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina

Objective:To conduct a meta-analysis assessing the perioperative,functional and oncological outcomes of partial nephrectomy(PN)and radical nephrectomy(RN)for T1b *** primary endpoints were the oncological *** secondary endpoints were the perioperative and functional ***:A systematic literature review was performed by searching multiple databases through February 2019 to identify eligible comparative studies according to the Preferred Reporting Items for Systematic Review and Meta-analysis *** reports were assessed according to the Newcastle-Ottawa Scale for nonrandomized controlled ***:Overall,13 retrospective cohort studies were included in the *** undergoing PN were younger(weighted mean difference[WMD]3.49 years,95%confidence interval[CI]5.16 to1.82;p<0.0001)and had smaller masses(WMD0.45 cm,95%CI0.59 to0.31;p<0.0001).There were no differences in the oncological outcome,which was demonstrated by progression-free survival(hazard ratio[HR]0.70;pZ0.22),cancerspecific mortality(HR 0.91;pZ0.57)and all-cause mortality(HR 1.01;pZ0.96).The two procedures were similar in estimated blood loss(WMD16.47 mL;pZ0.53)and postoperative complications(risk ratio[RR]1.32;pZ0.10),and PN provided better renal function preservation and was related to a lower likelihood of chronic kidney disease onset(RR 0.38;pZ0.006).Conclusion:PN is an effective treatment for T1b tumours because it offers similar surgical morbidity,equivalent cancer control,and better renal preservation compared to RN.

关键词： Kidney cancer Partial nephrectomy Radical nephrectomy Renal cancer Survival Renal function

基于非线性建模与拟合的永磁同步电机转子初始位置精确估计方法

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电机与控制学报 2024年第2期28卷 142-151页

作者：姚培煜冯国栋吴轩彭卫文丁北辰中山大学智能工程学院广东深圳518107 湖南大学电气与信息工程学院湖南长沙410082 中山大学先进制造学院广东深圳518107

针对永磁同步电机转子初始位置估计的精度与收敛速度受限问题,提出一种基于高频信号注入的非线性建模与拟合实现的初始位置估计方法。首先,建立初始位置与高频信号响应的关联模型,表明高频响应可用于直接计算初始位置,但直接计算结果在... 详细信息

针对永磁同步电机转子初始位置估计的精度与收敛速度受限问题,提出一种基于高频信号注入的非线性建模与拟合实现的初始位置估计方法。首先,建立初始位置与高频信号响应的关联模型,表明高频响应可用于直接计算初始位置,但直接计算结果在大部分转子位置易受测量噪声的影响。为此,提出基于多项式模型建立位置估计非线性模型,选取合适的模型参数,利用少量测试点拟合该模型,即可实现初始位置的快速精确估计,有效提高了估计精度与系统抗干扰能力。实验与仿真结果表明,相比现有方法,提出的方法易于实现,无需复杂滤波器与观测器设计,仅需要选取少量测试点即可快速估计精确转子初始位置,在保证估计精度的同时改进了传统估计方法收敛速度慢问题。

关键词：永磁同步电机高频信号注入转子初始位置估计多项式模型非线性模型

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保险科技浪潮下传统保险理论的变与不变

保险职业学院学报 2021年第2期35卷 31-34页

作者：丁北晨复旦大学经济学院上海200000

本文选取学界较为关注的传统保险理论,分风险管理理论和保险理论两部分,以理论分析和案例分析的方法,对保险科技浪潮下传统保险理论的变与不变进行论述。本文认为,保险最本质的理论如大数定律、四大基本原则是保险经营运作的基石,科技... 详细信息

本文选取学界较为关注的传统保险理论,分风险管理理论和保险理论两部分,以理论分析和案例分析的方法,对保险科技浪潮下传统保险理论的变与不变进行论述。本文认为,保险最本质的理论如大数定律、四大基本原则是保险经营运作的基石,科技是为了更好地去应用这些理论。而在保险发展过程中的逆选择和道德风险理论、对风险的定义,以及保险参与风险管理方式等理论则会顺应保险科技的发展而得到改变。

关键词：保险科技保险理论风险管理理论