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Design and Analysis of a Novel Tension Control Method for Winding Machine

Chinese Journal of Mechanical Engineering 2018年第6期31卷 79-94页

作者： xiao-Ming Xu Wu-xiang zhang xi-Lun Ding Ming zhang Shi-Hou Wei School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China China Academy of Space Technology Beijing 100094China

Filament winding has emerged as the main process for carbon fiber reinforced plastic(CFRP) fabrication, and tension control plays a key role in enhancing the quality of the winding products. With the continuous improvement of prod?uct quality and e ciency, the precision of the tension control system is constantly improving. In this paper, a novel tension control method is proposed, which can regulate the fiber tension and transport speed of the winding process by governing the outputs of three di erent driven rollers(the torque of the unwind roll, the torque of the magnetic powder brake roller, and the speed of the master speed roller) in three levels. The mechanical structures and dynamic models of the driven rollers and idle rollers are established by considering the time?varying features of the roller radius and inertia. Moreover, the influence of parameters and speed variation on fiber tension is investigated using the increment model. Subsequently, the control method is proposed by applying fiber tension in three levels accord?ing to the features of the three driven rollers. An adaptive fuzzy controller is designed for tuning the PID parameters online to control the speed of the master speed roller. Simulation is conducted for verifying the performance and sta?bility of the proposed tension control method by comparing with those of the conventional PID control method. The result reveals that the proposed method outperforms the conventional method. Finally, an experimental platform is constructed, and the proposed system is applied to a winding machine. The performance and stability of the tension control system are demonstrated via a series of experiments using carbon fiber under di erent reference speeds and tensions. This paper proposes a novel tension control method to regulate the fiber tension and transport speed.

关键词： Tension control Control method Fuzzy logic Filament winding

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The novel roles of circular RNAs in metabolic organs

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Genes & Diseases 2018年第1期5卷 16-23页

作者： Zhi-Chun zhang xiao-Long Guo xi Li Biology Science Institutes Chongqing Medical UniversityChongqing 400016PR China

Circular RNAs(circRNAs)with a covalently closed loop structure which was different with linear RNAs,recently re-merged as novel regulator and exerted function in multiple biological *** deep RNA sequencing(RNA-seq)technology coupled with bioinformatic analyses,a number of circRNAs has been ***,circRNAs exhibit tissue-and development-specific expression indicating their potential biological ***,function of circRNAs as miRNA sponge has been well demonstrated in some diseases,besides,circRNAs also could function as RNA binding protein sponge and regulate alternative splicing and gene ***,Emerging evidences showed that circRNAs played a pivotal role on the development of diseases including atherosclerotic vascular disease,neurological disorders and liver diseases,and served as diagnostic or predictive biomarkers of some *** review mainly discusses the current advance of circRNAs as regulator involved in many diseases,and highlights circRNAs which have been well elucidated biological and pathogenic mechanism.

关键词： Brain Circular RNAs Liver Metabolic disease Metabolism

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线粒体自噬调控骨代谢

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中国组织工程研究 2025年第8期29卷 1676-1683页

作者：朱汉民王松肖文琳张文静周茜何烨李微绍兴文理学院医学院浙江省绍兴市312099 湖北文理学院医学院湖北省襄阳市441053 海南省疾病预防控制中心海南省海口市570203

背景:近年来大量的研究表明,自噬和线粒体自噬在骨代谢过程中扮演着重要角色,非生理状态下的线粒体自噬会打破骨代谢的平衡导致代谢紊乱,对成骨细胞、破骨细胞、骨细胞、软骨细胞、骨髓间充质干细胞等均可产生影响。目的:归纳线粒体自... 详细信息

背景:近年来大量的研究表明,自噬和线粒体自噬在骨代谢过程中扮演着重要角色,非生理状态下的线粒体自噬会打破骨代谢的平衡导致代谢紊乱,对成骨细胞、破骨细胞、骨细胞、软骨细胞、骨髓间充质干细胞等均可产生影响。目的:归纳线粒体自噬调节骨代谢疾病的作用机制及在临床治疗领域的应用。方法:应用计算机检索PubMed、Web of Science、中国知网、万方和维普等数据库,中文关键词为“线粒体自噬,骨代谢,成骨细胞,破骨细胞,骨细胞,软骨细胞,骨髓间充质干细胞”,英文关键词为“mitophagy,bone metabolism,osteoblast,osteoclasts,osteocytes,chondrocytes,bone marrow mesenchymal stem cells”,检索文献时限为2008-2023年。依据入选标准对检索结果进行筛选排除,最终纳入90篇文献进行综述分析。结果与结论:线粒体自噬通过SIRT1、PINK1/Parkin、FOXO3、PI3K信号通路促进成骨细胞生成,通过PINK1/帕金森相关蛋白和SIRT1信号通路抑制破骨细胞功能,通过增加骨质中的磷酸钙颗粒和组织蛋白激酶K导致骨质流失,通过PINK1/帕金森相关蛋白、PI3K/AKT/mTOR、AMPK信号通路提高软骨细胞功能。尽管调控线粒体自噬在治疗骨病方面显示出巨大潜力,但仍有一些问题有待进一步探究,例如:药物激活线粒体自噬的不同阶段、不同信号通路的调控机制等。

关键词：线粒体自噬骨代谢成骨细胞破骨细胞骨细胞

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The Strongly Simple Cycles with Given Rotation Pairs of an Interval Map

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Acta Mathematica Sinica,English Series 2007年第1期23卷 37-40页

作者： Tai xiang SUN Hong Jian xi xiao Yan zhang Department of Mathematics Cuangxi University. Nanning 530004 P. R. China Department of Mathematics Guangxi College of Finance and Economics. Nanning 530004 P. R. China Department of Mathematics Guangxi University Nanning 530004. P. R. China

In this paper, we introduce the notion of the strongly simple cycles with some rotation pair for interval maps and prove that, if an interval map has a cycle with given rotation pair, then it, has a strongly simple cy... 详细信息

关键词： interval map strongly simple cycle rotation pair

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Feasibility of 3.0 T diffusion-weighted nuclear magnetic resonance imaging in the evaluation of functional recovery of rats with complete spinal cord injury

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Neural Regeneration Research 2015年第3期10卷 412-418页

作者： Duo zhang xiao-hui Li Xu Zhai xi-jing He Second Department of Orthopedics Second Affiliated Hospital of Xi’an Jiaotong University Department of Radiology Second Affiliated Hospital of Xi’an Jiaotong University

Diffusion tensor imaging is a sensitive way to reflect axonal necrosis and degeneration, glial cell regeneration and demyelination following spinal cord injury, and to display microstructure changes in the spinal cord in vivo. Diffusion tensor imaging technology is a sensitive method to diagnose spinal cord injury; fiber tractography visualizes the white matter fibers, and directly displays the structural integrity and resultant damage of the fiber bundle. At present, diffusion tensor imaging is restricted to brain examinations, and is rarely applied in the evaluation of spinal cord injury. This study aimed to explore the fractional anisotropy and apparent diffusion coefficient of diffusion tensor magnetic resonance imaging and the feasibility of diffusion tensor tractography in the evaluation of complete spinal cord injury in rats. The results showed that the average combined scores were obviously decreased after spinal cord transection in rats, and then began to increase over time. The fractional anisotropy scores after spinal cord transection in rats were significantly lower than those in normal rats （P 〈 0.05）; the apparent diffusion coefficient was significantly increased compared with the normal group （P 〈 0.05）. Following spinal cord transection, fractional anisotropy scores were negatively correlated with apparent diffusion coefficient values （r = -0.856, P 〈 0.01）, and positively correlated with the average combined scores （r = 0.943, P 〈 0.01）, while apparent diffusion coefficient values had a negative correlation with the average combined scores （r = -0.949, P 〈 0.01）. Experimental findings suggest that, as a non-invasive examination, diffusion tensor magnetic resonance imaging can provide qualita- tive and quantitative information about spinal cord injury. The fractional anisotropy score and apparent diffusion coefficient have a good correlation with the average combined scores, which reflect functional recovery after spinal cord injury.

关键词： nerve regeneration spinal cord injury spinal cord transection average combined score magnetic resonance imaging diffusion tensor imaging fractional anisotropy apparent diffusioncoefficient fiber tractography neural regeneration

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Optimal distributed power allocation for a new spectrum sharing paradigm in cognitive radio networks

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The Journal of China Universities of Posts and Telecommunications 2012年第3期19卷 37-43页

作者： zhang xiao-liang JI Hong LI xi DAI Li-yun Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications Beijing 100876 China School of Software and Communication Engineering Jiangxi University of Finance and Economics Nanchang 330013 China

The problem of power allocation in cognitive radio networks plays an important role to improve the efficiency of spectrum utilization. However, most of previous works focus on the power allocation for secondary users in spectrum sharing overlay or spectrum sharing underlay, which needs to frequently handoff between the idle spectrum bands or considers the interference constraints in all spectrum bands respectively. In order to reduce the handoff and fully utilize the spectrum resource, we propose a new spectrum sharing paradigm which not only can just need to adjust the transmit power in spectrum bands instead of frequently handoff between idle spectrum bands, but can fully utilize the spectrum resource as we only consider the interference power constraints in active spectrum bands rather than in all spectrum bands. Then based on this new spectrum sharing paradigm and the constraint conditions, we study the distributed power allocation for secondary users and formulate the optimization problem as a non-cooperative game problem, after that the variational inequality approach is used to solve this game problem and a Nash equilibria solution is got, finally simulation results are illustrated to demonstrate the performance of the proposed scheme.

关键词： resource allocation efficiency handoff spectrum sharing paradigm

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农民专业合作社运行发展现状调研——以临朐县为例

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长江蔬菜 2025年第1期 69-72页

作者：张培梅张茜临朐县农村经济发展服务中心农村财务指导科山东潍坊262600

发展农民专业合作社是完善现代化农业经营形式,优化土地资源配置,提高农产品质量,促进农业现代化建设的必由之路。在实践过程中,我国农民专业合作社还存在农民认识程度不深、政府扶持力度不足、合作社品牌效应不强等问题。为进一步了解... 详细信息

发展农民专业合作社是完善现代化农业经营形式,优化土地资源配置,提高农产品质量,促进农业现代化建设的必由之路。在实践过程中,我国农民专业合作社还存在农民认识程度不深、政府扶持力度不足、合作社品牌效应不强等问题。为进一步了解农民专业合作社运行情况,找准制约发展的瓶颈和问题,通过走访座谈、现场查看等形式,对临朐县农民专业合作社进行调研,了解和掌握农民专业合作社的发展现状和存在问题,并为农民专业合作社良好发展提出行之有效的建议,以推动农民专业合作社的规范化发展。

关键词：农民专业合作社调研报告临朐县

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Quantitative analysis of 3D vasculature for evaluation of angiogenesis in liver fibrosis with SR-μCT

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Nuclear Science and Techniques 2016年第5期27卷 255-263页

作者： Hai Tan Yi Fu Da-Dong Wang xi zhang Ti-Qiao xiao Shanghai Institute of Applied Physics Chinese Academy of Sciences Jiading Campus University of Chinese Academy of Sciences Department of Radiology Cancer Hospital Fudan University Department of Oncology Shanghai Medical College Fudan University Quantitative Imaging

The micro-CT imaging of vasculature is a powerful tool for evaluation of angiogenesis,a prominent characteristic of hepatic *** segment or bifurcation density,which is usually adopted to evaluate the degree of hepatic fibrosis,does not always work and may lead to incorrect assessment,especially when the threedimensional vasculature obtained is imperfect in sample preparation or image *** this paper,we propose a new parameter to solve this *** experimental results demonstrate that the method is robust and reliable,and is practical for angiogenesis evaluation,despite of image data *** quantitative analysis method can be extended to investigate other kinds of diseases in which vasculature change is a key indicator.

关键词：血管生成肝纤维化 CT成像评价三维定量分析方法图像采集样品制备

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Effect of channel diameter on magneto-thermal conversion ratio and consistency of each strand in a multi-strand induction heating tundish

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Journal of Iron and Steel Research International 2023年第6期30卷 1199-1210页

作者： Pu Wang Hong xiao xi-qing Chen Hai-yan Tang Jia-quan zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Magnetoelectric Research Institute Hunan Zhongke Electric Co.Ltd.Yueyang 414000HunanChina

The electromagnetic,flow,heat transfer and inclusions motion model of the channel-type induction heating(IH)tundish was established,and the effect of the channel diameter on the metallurgical behavior of the tundish was *** results show that the magnetic field in the channel of the IH tundish tends to concentrate on the surface layer and the side near the *** the channel diameter is increased from 100 to 180 mm,the maximum value of magnetic flux density in the channel decreases by 0.125 T,and the maximum value of electromagnetic force decreases by 11.83×10^(5) N m^(-3);however,the off-center distance of magnetic field increases by 9.4 mm,and the Joule heat in the channel decreases by 1004 kW,which leads to the reduction in temperature rising rate of the tundish from 1.41 to 0.59 K min^(-1).When the channel diameter is 100,140 and 180 mm,the maximum velocity at the channel exit before heating is 0.59,0.29 and 0.18 m s^(-1),and after heating for 1800 s,it is 1.52,1.12 and 0.92 m s^(-1),*** addition,the total inclusions escape ratio after heating for 1800 s with a channel diameter of 140 mm can be reduced by 12.39% compared to that before heating,and the maximum difference of escape ratios for each strand is only 4.51% and 5.32% before heating and after heating for 1800 s,*** with the channel diameters of 100 and 180 mm,the channel diameter of 140 mm is more favorable to improve the metallurgical effect of the IH tundish.

关键词： Induction heating tundish Channel diameter Joule heat Temperature rising rate Inclusion escape ratio

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Tuning the interfacial reaction environment via pH-dependent and induced ions to understand C–N bonds coupling performance in NO3- integrated CO2 reduction to carbon and nitrogen compounds over dual Cu-based N-doped carbon catalyst

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Journal of Energy Chemistry 2025年第1期100卷 273-285页

作者： Tianhang Zhou Chen Shen Zhenghao Wu xingying Lan Yi xiao College of Carbon Neutrality Future Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) Institute of Materials Science TU Darmstadt Department of Chemistry Xi'an Jiaotong-Liverpool University Department of Mechanical and Mechatronics Engineering and Waterloo Institute of Nanotechnology University of Waterloo Waterloo

Dual atomic catalysts （DAC）,particularly copper （Cu2）-based nitrogen （N） doped graphene,show great potential to effectively convert CO2and nitrate （NO3-） into important industrial chemicals such as ethylene,glycol,acetamide,and urea through an efficient catalytical process that involves C–C and C–N ***,the origin of the coupling activity remained unclear,which substantially hinders the rational design of Cu-based catalysts for the N-integrated CO2reduction reaction （CO2RR）.To address this challenge,this work performed advanced density functional theory calculations incorporating explicit solvation based on a Cu2-based N-doped carbon (Cu2N6C10) catalyst for *** calculations are aimed to gain insight into the reaction mechanisms for the synthesis of ethylene,acetamide,and urea via coupling in the interfacial reaction *** to the sluggishness of CO2,the formation of a solvation electric layer by anions （F-,Cl-,Br-,and I-） and cations (Na+,Mg2+,K+,and Ca2+) leads to electron transfer towards the Cu *** process significantly accelerates the reduction of *** results reveal that*CO intermediates play a pivotal role in N-integrated ***,the Cu2-based N-doped carbon catalyst examined in this study has demonstrated the most potential for C–N coupling to *** findings reveal that through the process of a condensation reaction between*CO and NH2OH for urea synthesis,*NO3-is reduced to*NH3,and*CO2to*CCO at dual Cu atom *** dual-site reduction facilitates the synthesis of acetamide through a nucleophilic reaction between NH3and the ketene ***,we found that the I-and Mg2+ions,influenced by pH,were highly effective for acetamide and ammonia synthesis,except when F-and Ca2+were ***,the mechanisms of C–N bond formation were investigated via ab-initio molecular dynamics simulations,and we found that adjusting the micro-environment can change the dominant side reaction,shift

关键词： pH-dependent micro-environments C–N coupling Dual Cu-based nitrogen carbon catalysts Explicit solvation model Ion stabilizer AIMD

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