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Looper-Tension Sliding Mode Control for Hot Strip Finishing Mills

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Journal of Iron and Steel Research International 2012年第1期19卷 23-30页

作者： ZHONG Zhao-zhun wang Jing-cheng ZHANG Jian-min LI Jia-bo Department of Automation Key Laboratory of System Control and Information Processing of Ministry of Education Shanghai Jiaotong University Shanghai 200240 China Baosteel Research Institute Baoshan Iron and Steel Co Ltd Shanghai 201900 China

An innovative sliding mode controller for looper and tension control in hot strip finishing mills was developed based on approximately linearized model. Firstly, a fictitious controller of the reduced order subsystem was designed according to desired dynamics, by which, the angle and tension loops were decoupled on the sliding manifold. Then, a sliding mode controller was used to validate finite time convergence of the state vector to the manifold which guaranteed the stability and performances of the overall system. This solution was considered owing to its well- known robustness and simplicity characteristics concerning disturbances and unmodelled dynamics. Simulation results showed the effectiveness of the proposed controller compared with conventional ones.

关键词： sliding mode control looper control tension control hot strip finishing mill

Virtual machine placement optimizing to improve network performance in cloud data centers

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The Journal of China Universities of Posts and Telecommunications 2014年第3期21卷 62-70页

作者： DONG Jian-kang wang Hong-bo LI Yang-yang cheng Shi-duan State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications

With the wide application of virtualization technology in cloud data centers, how to effectively place virtual machine （VM） is becoming a major issue for cloud providers. The existing virtual machine placement （VMP） solutions are mainly to optimize server resources. However, they pay little consideration on network resources optimization, and they do not concern the impact of the network topology and the current network traffic. A multi-resource constraints VMP scheme is proposed. Firstly, the authors attempt to reduce the total communication traffic in the data center network, which is abstracted as a quadratic assignment problem; and then aim at optimizing network maximum link utilization （MLU）. On the condition of slight variation of the total traffic, minimizing MLU can balance network traffic distribution and reduce network congestion hotspots, a classic combinatorial optimization problem as well as NP-hard problem. Ant colony optimization and 2-opt local search are combined to solve the problem. Simulation shows that MLU is decreased by 20%, and the number of hot links is decreased by 37%.

关键词： cloud computing data center network virtual machine placement traffic engineering network performance

Advanced Electrical Motors and Control Strategies for High-quality Servo Systems-A Comprehensive Review

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Chinese Journal of Electrical Engineering 2024年第1期10卷 63-85页

作者： Ming cheng Jiawei Zhou Wei Qian bo wang Chenchen Zhao Peng Han School of Electrical Engineering Southeast UniversityNanjing 210096China ESTUN Automation Co. Ltd.Nanjing 211106China Ansys Inc.San JoseCA 95134USA

Recent technological advancements have propelled remarkable progress in servo systems,resulting in their extensive utilization across various high-end applications.A comprehensive review of high-quality servo system technologies,focusing specifically on electrical motor topologies and control strategies is *** terms of motor topology,this study outlines the mainstream servo motors used across different periods,as well as the latest theories and technologies surrounding contemporary servo *** terms of control strategies,two well-established approaches are presented:field-oriented control and direct torque ***,it discusses advanced control strategies employed in servo systems,such as model predictive control(MPC)and fault tolerance control,among others.

关键词： Servo system servo motor control strategy magnetic field modulation

Assessment of Transcatheter or Surgical Closure of Atrial Septal Defect using Interpretable Deep Keypoint Stadiometry

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Research 2023年第2期2022卷 319-328页

作者： Jing wang Wanqing Xie Mingmei cheng Qun Wu Fangyun wang Pei Li bo Fan Xin Zhang Binbin wang Xiaofeng Liu School of Basic Medical Sciences Capital Medical UniversityBeijing 100069China Department of Intelligent Medicalnginering School of Bmedical EngineeringAnhui Medical UnierityHefei 230032China Beth Israel Deaconess Medical Center Harvard Medical SchoolHarvard UniversityBostonMA 225USA Heart Center Beijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBejing 10045China Center for Genetics National Research Institute for Family PlanningBeijing 100730China Graduated school Peking Union Medical CollegeBeijing 100730China Gordon Center for Medical Imaging Harvard Medical Schooland Massachusetts General HospitalBostonMA 02114USA

Automated echocardiogram interpretation with artificial intelligence(Al)has the potential to facilitate the serial diagnosis of heart defects by primary ***,the fully automated and interpretable analysis pipeline for ... 详细信息

关键词： diagnosis Surgical Deep

Low remanence temperature coefficient Sm1-xErx(Co,Fe,Cu,Zr)z magnets operating up to 400℃

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Rare Metals 2020年第1期39卷 70-75页

作者： Tian-Li Zhang bo Zhang Hui wang cheng-Bao Jiang Zhi-Hong Zhang Xiao-Qing wang Wei Zhang School of Materials Science and Engineering Beihang UniversityBeijing100191China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou014030China

Er-doped Sm1-xErx(CobalFe0.15Cu0.08Zr0.03)7.8(x=0,0.1,0.2,0.3)magnets with a low remanence temperature coefficient were prepared by powder metallurgy *** influence of Er content on the remanence and microstructure was investigated.X-ray diffractometer(XRD)analysis showed that the magnets with different Er contents consist of 2:17 R phase and 1:5 H *** electron microscopy(SEM)analysis showed that the composition of the matrix is consistent with stoichiometric composition and no obvious precipitated phase *** the increase in doped Er amount,the temperature stability of Sm1-xErx(CobalFe0.15Cu0.08Zr0.03)7.8(x=0,0.1,0.2,0.3)is getting *** x is up to 0.3,the magnets with a low remanence temperature coefficient are obtained and the remanence descends tardily from 0.86 to 0.80 T as the temperature rises from room temperature to 400℃.These results indicate that Er substitution for Sm in SmCobased permanent magnets together with optimal composition and proper heat treatment could achieve a desired magnetic performance combined with high thermal stability.

关键词： Permanent magnets Low remanence temperature coefficient Er doped Magnetic performance characterization

Comparison of Clinic and Ambulatory Blood Pressure in Response to Antihypertensive Drugs in Chinese Patients

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Biomedical and Environmental Sciences 2007年第4期20卷 279-283页

作者： XIAO-RU cheng YANG wang bo HU XUAN JIA WEI LI National Center for Cardiovascular Diseases Cardiovascular Institute ＆ Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

To compare the difference between 24-h ambulatory blood pressure （ABP） and trough clinic blood pressure （CBP） after 8 weeks of therapy. Methods The study used meta-regression analysis to summarize three randomized, double-blind, active controlled trials in order to compare the difference between the magnitude of the reduction in 24-h average ABP and CBP Patients. Chinese patients with seated diastolic blood pressure （SDBP） 95-115 mmHg and ambulatory diastolic blood pressure （ADBP）≥85 mmHg. Results The average age of 126 patients was 47.7 ＋ 8.3 years, ranging from 25 to 67 （95 males and 31 females）. All regimens reduced 24-h ABP and CBP after 8 weeks of treatment. In the 126 patients the baseline 24-h SBP and DBP values （142.7/94.4 mmHg） were markedly lower than those for clinic values （152.6/102.6 mmHg; P〈0.0001）. Similarly, the 24-h SBP and DBP values （132.7/87.7 mmHg） in week 8 were markedly lower than the clinic values （138.9/92.7 mmHg; P〈0.0001）. The differences between the treatment-induced reductions in 24-h ABP and CBP were statistically significant （the difference was 3.7/3.3 mmHg for SBP/DBP, P=***69/P〈O.O001）. Conclusion All regimens significantly reduced seated CBP and ABP. The effect of antihypertensive treatment was greater on CBP than that on ABP, suggesting that assessment on effectiveness of an antihypertensive treatment using CBP readings only has to be carefully interpreted, and a more systematic application of ABP monitoring should be adopted.

关键词： Ambulatory blood pressure Antihypertensive treatment Clinic blood pressure Essential Hypertension

Microstructure and shear properties evolution of Mn-doped SAC solder joint under isothermal aging

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Journal of Iron and Steel Research International 2023年第8期30卷 1650-1660页

作者： cheng-ming Li Shu-jin Chen Shan-shan Cai Ju-bo Peng Xiao-jing wang Ying-wu wang School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina R&D Center Yunnan Tin Group(Holding)Co.Ltd.Kunming 650000YunnanChina Modern School of Engineering Yunnan UniversityKunming 650091YunnanChina

The effects of Mn addition(0.005,0.01,0.03,0.05,and 0.07 wt.%)on microstructure,shear mechanical behavior,and interfacial thermal stabilities of SAC305 joints were investigated under isothermal aging temperatures of 170 C with different aging time(0,250,500,and 750 h).It is found that Mn addition can increase fracture energy of joints without decreasing the shear *** the microstructures have transformed from the eutectic net-like structure in SAC305 solder joints into the structures based onβ-Sn matrix with intermetallic compounds(IMCs)*** doping 0.07 wt.%Mn,the Cu_(6)Sn_(5) growth along the SAC305/Cu interface during thermal aging can be inhibited to some *** isothermal aging at 170°C,the maximum shear force of solder joint decreases continuously with aging time increasing,while the fracture energy rises first and then decreases,reaching the maximum at 500 h compared by that with the microstructure ***_(3)Sn growth between Cu_(3)Sn_(5)/Cu interface has been retarded most at the aging time of 250 h with 0.07 wt.%Mn-doped *** the aging time prolonging,the inhibition effect of Mn on CusSn IMC layer becomes *** strengthening effect of Mn can be explained by precipitation strengthening,and its mechanical behavior can be predicted by particle strengthening model proposed by Orowan.

关键词： SAC305 solder Mn doping Shear mechanical behavior Isothermal aging Interfacial intermetallic compound

Solid-State Hydrogen Storage Properties of Ti-V-Nb-Cr High-Entropy Alloys and the Associated Effects of Transitional Metals(M=Mn,Fe,Ni)

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Acta Metallurgica Sinica(English Letters) 2023年第7期36卷 1113-1122页

作者： bo cheng Yunkai Li Xiaoxi Li Huibin Ke Liang wang Tangqing Cao Di Wan Benpeng wang Yunfei Xue Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing314019China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing100081China Department of Mechanical and Industrial Engineering Norwegian University of Science and Technology7491TrondheimNorway

Recently,high-entropy alloys(HEAs)designed by the concepts of unique entropy-stabilized mechanisms,started to attract widespread interests for their hydrogen storage *** with body-centered cubic(BCC)structures present a high potential for hydrogen storage due to the high hydrogen-to-metal ratio(up to H/M=2)and vastness of *** many studies reported rapid absorption kinetics,the investigation of hydrogen desorption is missing,especially in BCC *** have investigated the crystal structure,microstructure and hydrogen storage performance of a series of HEAs in the Ti-V-Nb-Cr *** types of TiVCrNb HEAs(Ti_(4)V_(3)NbCr_(2),Ti_(3)V_(3)Nb2Cr_(2),Ti_(2)V_(3)Nb_(3)Cr_(2))with close atomic radii and different valence electron concentrations(VECs)were designed with single BCC phase by CALPHAD *** three alloys with fast hydrogen absorption kinetics reach the H/M ratio up to ***,Ti_(4)V_(3)NbCr_(2)alloy shows the hydrogen storage capacity of 3.7 wt%,higher than other HEAs ever *** dehydrogenation activation energy of HEAs’hydride has been proved to decrease with decreasing VEC,which may be due to the weakening of alloy atom and H ***,Ti_(4)V_(3)NbCr_(2)M(M=Mn,Fe,Ni)alloys were also synthesized to destabilize *** addition of Mn,Fe and Ni lead to precipitation of Laves phase,however,the kinetics did not improve further because of their own excellent hydrogen *** increasing the content of Laves phase,there appear more pathways for hydrogen desorption so that the hydrides are more easily dissociated,which may provide new insights into how to achieve hydrogen desorption in BCC HEAs at room temperature.

关键词： High-entropy alloy Hydrogen storage CALPHAD Hydride stability Hydrogen sorption kinetics

Multi-distortion suppression for neutron radiographic images based on generative adversarial network

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Nuclear Science and Techniques 2024年第4期35卷 176-188页

作者： cheng-bo Meng wang-Wei Zhu Zhen Zhang Zi-Tong wang Chen-Yi Zhao Shuang Qiao Tian Zhang School of Physics Northeast Normal UniversityChangchun 130024China

Neutron radiography is a crucial nondestructive testing technology widely used in the aerospace,military,and nuclear ***,because of the physical limitations of neutron sources and collimators,the resulting neutron radiographic images inevitably exhibit multiple distortions,including noise,geometric unsharpness,and white ***,these distortions are particularly significant in compact neutron radiography systems with low neutron ***,in this study,we devised a multi-distortion suppression network that employs a modified generative adversarial network to improve the quality of degraded neutron radiographic *** neutron radiographic image datasets with various types and levels of distortion were built for the first time as multi-distortion suppression ***,the coordinate attention mechanism was incorporated into the backbone network to augment the capability of the proposed network to learn the abstract relationship between ideally clear and degraded *** experiments were performed;the results show that the proposed method can effectively suppress multiple distortions in real neutron radiographic images and achieve state-of-theart perceptual visual quality,thus demonstrating its application potential in neutron radiography.

关键词： Neutron radiography Multi-distortion suppression Generative adversarial network Coordinate attention mechanism