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CSEE Journal of Power and Energy Systems 2024年第2期10卷 584-592页

作者： zhi ding Tianyao Ji Mengshi Li Q.H.Wu School of Electric Power Engineering South China University of Technology(SCUT)Guangzhou 510641China

In this paper, a novel signal processing method combining mathematical morphology (MM) and Walsh theory is proposed, which uses Walsh functions to control the structuring element (SE) and MM operators. Based on the Walsh-MM method, a scheme for power quality disturbances detection and classification is developed, which involves three steps: denoising, feature extraction and morphological clustering. First, various evolution rules of Walsh function are used to generate groups of SEs for the multiscale Walsh-ordered morphological operation, so the original signal can be denoised. Next, the fundamental wave of the denoised signal is suppressed by Hadamard matrix;thus, disturbances can be extracted. Finally, the Walsh power spectrum of the waveform extracted in the previous step is calculated, and the parameters of which are taken by morphological clustering to classify the disturbances. Simulation results reveal the proposed scheme can effectively detect and classify disturbances, and the Walsh-MM method is less affected by noise and only involves simple calculation, which has a potential to be implemented in hardware and more suitable for real-time application.

关键词： Hadamard matrix mathematical morphology morphological clustering power quality disturbance Walsh theory

State of the art in movement around a remote point:a review of remote center of motion in robotics

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Frontiers of Mechanical Engineering 2024年第2期19卷 1-28页

作者： Wuxiang ZHANG zhi WANG Ke MA Fei LIU Pengzhi CHENG Xilun ding School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 315832China Intelligent Aerospace Manufacturing Engineering Technology Co. Ltd.Beijing 100191China

The concept of remote center of motion(RCM)is pivotal in a myriad of robotic applications,encompa-ssing areas such as medical robotics,orientation devices,and exoskeletal *** efficacy of RCM technology is a determining factor in the success of these robotic *** paper offers an exhaustive review of RCM technologies,elaborating on their various methodologies and practical *** delves into the unique characteristics of RCM across different degrees of freedom(DOFs),aiming to distill their fundamental *** addition,this paper categorizes RCM approaches into two primary classifications:design based and control *** are further organized according to their respective DOFs,providing a concise summary of their core *** upon the understanding of RCM’s versatile capabilities,this paper then transitions to an in-depth exploration of its applications across diverse robotic *** this review,we critically analyze the existing research challenges and issues that are inherently present in both RCM methodologies and their *** discussion is intended to serve as a guiding framework for future research endeavors and practical deployments in related areas.

关键词： remote center of motion mechanism robotics medical robot orientation device exoskeleton

Transcriptome-based analysis of key signaling pathways affecting the formation of primordial germ cell in chickens

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Journal of Integrative Agriculture 2024年第5期23卷 1644-1657页

作者： Ying ding Qiong zhi Qisheng Zuo Kai Jin Wei Han Bichun Li Key Laboratory of Animal Genetics Breeding and Molecular Design of Jiangsu ProvinceCollege of Animal Science and TechnologyYangzhou UniversityYangzhou 225009China Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China Yangzhou UniversityYangzhou225009China Poultry Research Institute Chinese Academy of Agricultural Sciences/Jiangsu Institute of Poultry ScienceYangzhou 225009China

Bone morphogenetic protein 4(BMP4)can induce the formation of chicken primordial germ cells(PGCs)in vitro;however,its regulatory mechanism in poultry remains *** study aimed to use RNA-seq to analyze PGCs in chicken embryos and iPGCs induced by BMP4 in vitro,clarify the internal regulatory factors of PGCs,analyze the mechanism of the formation of PGCs,and lay a theoretical foundation for the further optimization of PGCs induction *** stem cells(ESCs),PGCs and iPGCs induced by BMP4 in vitro were *** transcriptional maps of the three cell types were studied using *** results showed 6,142 genes differentially expressed between PGCs and iPGCs,of which 2,728 were upregulated in iPGCs and 3,414 were downregulated in *** to that in ESCs,BMP4 was significantly upregulated in PGCs and *** results showed that both the TGF-βand Wnt signaling pathways were activated during the formation of PGCs in vitro and in vivo,and the activation was more significant during iPGCs induced by *** expression of Nodal,an inhibitory factor of TGF-βsignaling,was significantly decreased in PGCs and iPGCs,but was not expressed in iPGCs,which further supports our ***,the Lysosome and PI3K-AKT signaling pathways were significantly enriched in PGCs and iPGCs,***,transmission electron microscopy(TEM)results showed that the number of autolysosomes was significantly higher after the addition of BMP4,which is consistent with the KEGG ***,the number of PGCs was significantly reduced after ATG14 was interfered in vivo and in *** conclusion,this study screened out the key signaling pathways during the formation of PGCs,aiming to provide help for enriching the mechanism network regulating PGCs formation in chicken and laying a theoretical foundation for further improving the efficiency of inducing PGCs in vitro.

关键词： RNA-seq BMP4 PGCs ATG14 chicken

A 3D-printed microhemispherical shell resonator with electrostatic tuning for a Coriolis vibratory gyroscope

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Microsystems & Nanoengineering 2024年第2期10卷 25-35页

作者： Baoyin Hou Ye Zhu Chaofan He Weidong Wang zhi ding Wen He Yong He Lufeng Che College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou310027China Center for Microelectronics Shaoxing InstituteZhejiang UniversityShaoxing312035China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310058China

The emergence of microhemispherical resonant gyroscopes,which integrate the advantages of exceptional stability and long lifetime with miniaturization,has afforded new possibilities for the development of whole-angle ***,existing methods used for manufacturing microhemispherical resonant gyroscopes based on MEMS technology face the primary drawback of intricate and costly ***,we report the design,fabrication,and characterization of the first 3D-printable microhemispherical shell resonator for a Coriolis vibrating *** remarkably achieve fabrication in just two steps bypassing the dozen or so steps required in traditional *** utilizing the intricate shaping capability and ultrahigh precision offered by projection microstereolithography,we fabricate 3D high-aspect-ratio resonant structures and controllable capacitive air gaps,both of which are extremely difficult to obtain via MEMS *** addition,the resonance frequency of the fabricated resonators can be tuned by electrostatic forces,and the fabricated resonators exhibit a higher quality factor in air than do typical MEMS microhemispherical *** work demonstrates the feasibility of rapidly batch-manufacturing microhemispherical shell resonators,paving the way for the development of microhemispherical resonator gyroscopes for portable inertial ***,this particular design concept could be further applied to increase uptake of resonator tools in the MEMS community.

关键词： resonator tuning electrostatic

Practice and reflection on the teaching of the reproductive system

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Medical Bulletin of Shanghai Jiaotong University 2015年第2期27卷 143-148页

作者： zhi-de ding Ping-ping WU Ting-ting WU Yong FAN Ya-li XU department of Anatomy Histology and EmbryologyShanghai Jiao Tong University School of Medicine department of Pathology Shanghai Jiao Tong University School of Medicine

Objective To review and explore the advantages and disadvantages of the teaching of the reproductive system in Shanghai Jiao Tong University School of Medicine,in order to provide a feasible scheme for the subsequent reform of the teaching system,including the syllabus design and the optimization of the teaching method,*** With the one-year practice in the teaching of the reproductive system,this paper has explored the achievements in the implementation of this teaching system from three aspects,including the teaching experience and feelings of teachers,student questionnaires and test ***,this paper has also deeply analyzed some problems that may exist or be derived from the teaching practice in that teaching *** The new teaching method has huge differences from the traditional"discipline-oriented"teaching method in the curricular design,teachers’lecture form,students’learning skills and examination types,*** is more important,the new teaching method will significantly renew the concepts of both teaching and *** The method of the systemic teaching is one of the critical ways to realize the reform of the medical education,and can also provide the necessary basis for the cultivation of professional high-quality teachers required in the medical education.

关键词： Systemic teaching reproductive system teaching method medical education

Microstructures and mechanical properties of a commercial Mg-Al-Zn-Mn alloy with various hot-extrusion processes

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Rare Metals 2024年第3期43卷 1329-1336页

作者： He Ma Fan-zhi Meng Qiang Yang Ze-Feng Xie Yuan-ding Huang Xin Qiu State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun130022China MagIC-Magnesium Innovation Center Helmholtz-Zentrum Geesthacht21502GeesthachtGermany Engineering Research Center of Optoelectronic Functional Materials Ministry of EducationChangchun University of Science and TechnologyChangchun130022China

Mg-Al-Zn-Mn(AZ)system alloys have become widely used due to their good castability,excellent formability and outstanding corrosion resistance[1-6].However,their strength is still much lower than that of traditional Mg... 详细信息

关键词： alloys alloy corrosion

Synthesis of Organic-Inorganic Hybrid Aluminum Hypophosphite Microspheres Flame Retardant and Its Flame Retardant Research on Thermoplastic Polyurethane

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 221-233页

作者：刘生鹏 XU zhi ZHANG Xinyuan WEI Huan XIONG Yun ding Yigang HUANG Wenbo 许莉莉 Engineering Research Center of Phosphorus Resources development and Utilization of Ministry of Education Key Laboratory for Green Chemical Process of Ministry of EducationSchool of Chemical Engineering and PharmacyWuhan Institute of TechnologyWuhan 430205China Hubei Three Gorges Laboratory Yichang 443007China School of Technology Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China

Aluminum hypophosphite microspheres(AHP) were synthesized by hydrothermal method using NaH2PO2·H2O and AlCl3·6H2O as raw materials, and then the AHP microspheres were polymerized by surface polymerization of micro-nanospheres with cyclic cross-linked poly(cyclotriphosphazene-co-4,4'-sulfonyldiphenol)(PZS). A new organic-inorganic poly(phosphonitrile)-modified aluminum hypophosphite microspheres(PZS-AHP) were synthesized by encapsulation and applied to flame retardant thermoplastic polyurethane(TPU). The microstructure and chemical composition of the PZS-AHP microsphere were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray spectroscopy. The thermal stability of PZS-AHP microsphere was explored with thermogravimetric analysis. Thermogravimetric data indicate that the PZS-AHP microspheres have excellent thermal stability. The thermal and flame-retarding properties of the TPU composites were evaluated by thermogravimetric(TG), limited oxygen index tests(LOI), and cone calorimeter test(CCT). The TPU composite achieved vertical burning(UL-94) V-0 grade and LOI value reached 29.2% when 10 wt% PZS-AHP was incorporated. Compared with those of pure TPU, the peak heat release rate(pHRR) and total heat release(THR) of TPU/10%PZS-AHP decreased by 82.2% and 42.5%, respectively. The results of CCT indicated that PZS-AHP microsphere could improve the flame retardancy of TPU composites.

关键词： polyphosphazene thermoplastic polyurethane flame retardancy aluminum hypophosphite surface polymerization

Exploratory practice of bilingual education integrated with the PBL model in the teaching of histology and embryology

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Medical Bulletin of Shanghai Jiaotong University 2015年第2期27卷 165-168页

作者： Ting-ting WU Jian-guo LI Song YU zhi-de ding Chen XU department of Anatomy Histology and EmbryologyShanghai Jiao Tong University School of Medicine

The bilingual education integrated with PBL method is a new teaching model which gives consideration to knowledge,ability and professional foreign *** reflects the international integration for the reform idea of medical *** teaching practice indicated this model might be feasible in histology and *** brings not only the classic medical knowledge but also the latest medical developments to the *** new teaching model plays a role in the cultivation of the ability to solve problems independently and team spirit for *** helps students to improve their knowledge,skills,level of foreign language and quality.

关键词： reform of medical education bilingual education problem-based learning histology and embryology

Buckling Properties of Water-Drop-Shaped Pressure Hulls with Various Shape Indices Under Hydrostatic External Pressure

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China Ocean Engineering 2024年第1期38卷 1-17页

作者： ding Xiao-de ZHANG Jian WANG Fang JIAO Hui-feng WANG Ming-lu School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Shanghai Engineering Research Center of Marine Renewable Energy College of Engineering Science and Technol-ogyShanghai Ocean UniversityShanghai 201306China China Ship Scientific Research Center Wuxi 214082China

The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater ***,this study conducted analytical,experimental and numerical investigation of the buckling properties of water-drop-shaped pressure hulls under hydrostatic pressure.A water-drop experiment was conducted to design water-drop-shaped pressure hulls with various shape *** critical loads for the water-drop-shaped pressure hulls were resolved by using Mushtari’s *** numerical simulations including linear buckling analysis and nonlinear buckling analysis including eigenmode imperfections were *** results indicated that the critical loads resolved by Mushtari's formula were in good agreement with the linear buckling loads from the numerical *** formula can be extended to estimate the buckling capacity of water-drop-shaped pressure *** addition,three groups of pressure hulls were fabricated by using stereolithography,a rapid prototyping ***,three groups of the pressure hulls were subjected to ultrasonic measurements,optical scanning,hydrostatic testing and numerical *** experimental results were consistent with the numerical *** results indicate that the sharp end of the water-drop-shaped pressure hulls exhibited instability compared with the blunt *** paper provides a new solution to the limitations of experimental studies on the water-drop-shaped pressure hulls as well as a new configuration and evaluation method for underwater observatories.

关键词： buckling pressure hull water drop underwater observatory

A computational model to identify fertility-related proteins using sequence information

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Frontiers of Computer Science 2024年第1期18卷 229-237页

作者： Yan LIN Jiashu WANG Xiaowei LIU Xueqin XIE de WU Junjie ZHANG Hui ding Key Laboratory for Animal Disease-Resistance Nutrition of the Ministry of Agriculture Animal Nutrition InstituteSichuan Agricultural UniversityChengdu 611130China School of Life Science and Technology and Center for Informational Biology University of Electronic Science and Technology of ChinaChengdu 610054China

Fertility is the most crucial step in the development process,which is controlled by many fertility-related proteins,including spermatogenesis-,oogenesis-and embryogenesis-related *** identification of fertility-related proteins can provide important clues for studying the role of these proteins in ***,in this study,we constructed a two-layer classifier to identify fertility-related *** this classifier,we first used the composition of amino acids(AA)and their physical and chemical properties to code these three fertility-related ***,the feature set is optimized by analysis of variance(ANOVA)and incremental feature selection(IFS)to obtain the optimal feature *** five-fold cross-validation(CV)and independent data tests,the performance of models constructed by different machine learning(ML)methods is evaluated and ***,based on support vector machine(SVM),we obtained a two-layer model to classify three fertility-related *** the independent test data set,the accuracy(ACC)and the area under the receiver operating characteristic curve(AUC)of the first layer classifier are 81.95%and 0.89,respectively,and them of the second layer classifier are 84.74%and 0.90,*** results show that the proposed model has stable performance and satisfactory prediction accuracy,and can become a powerful model to identify more fertility related proteins.

关键词： sfertility-related proteins machine1 learning sequence information feature selection