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Coupling Dynamic Model of Chatter for Cold Rolling

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Journal of Iron and Steel Research(International) 2010年第12期17卷 30-34页

作者： YANG Xu tong chao-nan YUE Guang-feng MENG Jian-ji School of Information Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory of Advanced Control of Iron and Steel Process (Ministry of Education) University of Science and Technology- Beijing Beijing 100083 China Central Research Institute of Building and Construction Co Ltd MCC Group Beijing 100088 China

In order to build high accuracy integral dynamic models of cold rolling mill system, by analyzing the vibration process of cold rolling, the dynamic model of 4-h mill, including the rolling process model, the mill roll stand structure model and the hydraulic servo system model is built. These three models are coupled and linearized, then the multiple input and multiple output （MIMO） linear transfer function model of single stand 4-h cold mill system is obtained. The model with the proposed data proves its validity, meanwhile the effects of different working conditions on the stability of cold rolling mill system have been discussed. Simulation resulsts show that the model accords with former models and has its own advancement. It contributes to the further study and supression of coupling vibraiton.

关键词： cold rolling chatter dynamic modeling coupling simulation

Filiform needle acupuncture for allergic rhinitis:A systematic review and meta-analysis

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Journal of Integrative Medicine 2022年第6期20卷 497-513页

作者： Shi-hao Du Wei Guo chao Yang Sheng Chen Sheng-nan Guo Shuo Du Zhong-ming Du Yu-tong Fei Ji-ping Zhao Dongzhimen Hospital Beijing University of Chinese MedicineBeijing100700China Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing100700China Centre for Evidence-Based Chinese Medicine Beijing University of Chinese Medicine100029BeijingChina

Background:Filiform needle acupuncture(FNA),the most classical and widely applied acupuncture method based on traditional Chinese medicine theory,has shown a promising effect in the treatment of allergic rhinitis(AR).Objective:To evaluate the efficacy,safety,cost-effectiveness,and patient preference of FNA in the treatment of AR by comparing FNA with sham acupuncture,no treatment,and conventional medication.Search strategy:Eight electronic databases were systematically searched from inception to October 14,2021.Additional studies were acquired from clinical trial registration platforms and reference lists.Inclusion criteria:Randomized controlled trials were included if they compared FNA with either sham acupuncture,no treatment or conventional medication for AR.Data extraction and analysis:Two researchers extracted data independently of each other using a predesigned data acquisition form,and results were cross-checked after completion.The primary outcome was symptom score(Total Nasal Symptom Score or Visual Analogue Scale),and the secondary outcomes were the AR control questionnaire,quality of life(QoL)score(Different versions of Rhinoconjunctivitis Quality of Life Questionnaire),medication score(use of rescue medication),mental health score,total IgE,adverse event rate,clinical economic indicators,and patient satisfaction score.Standardized mean difference(SMD)or mean difference(MD)with 95% confidence interval was used to calculate the effect size for continuous data,while risk ratio with 95%CI was used for dichotomous data.Results:Thirty studies were included in this review.Compared with sham acupuncture,FNA significantly reduced the symptom score(SMD:-0.29[-0.43,-0.15]),AR’s impact on QoL(SMD:-0.23[-0.37,-0.08])and medication score(SMD:-0.3[-0.49,-0.11]).Compared with no treatment,FNA dramatically reduced the symptom score(SMD:-0.8[-1.2,-0.39])and AR’s impact on QoL(SMD:-0.82[-1.13,-0.52]).There were no increased rates of adverse events with FNA compared to sham acupuncture and no treatment.FNA increased pati

关键词： Allergic rhinitis Filiform needle acupuncture Systematic review Meta-analysis

Firm embedding behavior of annular grooved projectiles impacting ductile metal targets

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Defence Technology（防务技术） 2019年第5期15卷 768-778页

作者： Qi Huang Shun-shan Feng Xu-ke Lan chao-nan Chen Yong-xiang Dong tong Zhou State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

Annular grooved projectiles(AGPs)have drawn ongoing concerns as an advanced penetrator for their excellent anti-rebound capability in impacting metal plates.They could become embedded solidly in the target surface during low-velocity impact.In this investigation,the firm embedding behavior of AGP was observed by impact experiments.Corresponding numerical simulations provided a better understanding of this process.Experimental and numerical results indicated that the firm embedding behavior of AGP was mainly due to the filling-material in the groove rather than the friction between the projectile and target,unlike traditional shape such as conical projectile.According to observation,firm embedding process can generally be subdivided into four stages:initial-cratering stage,groove-filling stage,fillingmaterial failure stage and rebound vibration stage.Moreover,the damage mechanics of target material around crater was obtained through microscopic tests.A comparison of the cross-sectional figures between the experiment and simulation proved that the analysis and the proposed method were reasonable and feasible,which further demonstrated that the firm embedding behavior has application potential in new concept warheads.

关键词： Annular grooved projectile (AGP) Impact Firm embedding behavior Flow characteristics Microscopic tests

Load Distribution Optimization of Hot Strip Mills with Evolutionary Algorithm for Complex-process Optimization

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Load Distribution Optimization of Hot Strip Mills with Evolu...

2011 4th IEEE International Conference on Computer Science and Information Technology(ICCSIT 2011)

作者： HU Chang-bin tong chao-nan Key Laboratory of Advanced Control of Iron and Steel Process （Ministry of Education） University of Science and Technology Beijing

ISBN: (纸本)9781612848334

The evolutionary algorithm for complex-process optimization （EACOP） which has a flexible framework structure achieves load distribution including gauge and shape of hot rolling mill. The algorithm is embedded in various sub- methods that have search mechanism within the flexible framework, according to model’s characteristics of load distribution, with latin hypercube uniform sampling to improve initial diverse population strategy. Second, super- rectangle produced by go-beyond strategy is applied to in- depth search and improve the efficiency of the local optimal solution. The results show that the algorithm is able to use fewer adjustable parameters to complete to search and get feasible mathematical solution for the actual load distribution problems.

关键词： load-distribution scatter search evolutionary algorithm Complex-process optimization

来源： cnki会议评论

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cnki会议

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一类不确定系统鲁棒容错D-稳定性分析

控制与决策 2009年第5期24卷 641-647页

作者：陈明童朝南北京科技大学信息工程学院北京100083

研究不确定系统D-稳定鲁棒容错H∞控制问题.基于连续型执行器故障模式,利用线性矩阵不等式(LMI)给出了系统D-稳定的鲁棒容错输出反馈控制器存在的充分条件,并将动态输出反馈控制器设计方法归结为求解一族线性矩阵不等式组.仿真示例表明... 详细信息

研究不确定系统D-稳定鲁棒容错H∞控制问题.基于连续型执行器故障模式,利用线性矩阵不等式(LMI)给出了系统D-稳定的鲁棒容错输出反馈控制器存在的充分条件,并将动态输出反馈控制器设计方法归结为求解一族线性矩阵不等式组.仿真示例表明,无论执行器是否发生故障,所得到的动态输出反馈控制器不仅保证闭环系统是D-稳定的,而且满足给定的H∞干扰指标,从而验证了所提出的控制器设计方法的有效性.

关键词： D-稳定性线性矩阵不等式容错控制输出反馈鲁棒性

不确定系统鲁棒容错H_∞控制的LMI设计方法

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控制与决策 2009年第4期24卷 526-531页

作者：陈明童朝南北京科技大学信息工程学院北京100083

针对不确定线性系统,研究了执行器失效情况下鲁棒容错H∞控制问题.基于连续增益故障模式,利用线性矩阵不等式LMI推导了系统H∞指标约束下鲁棒容错镇定的充要条件,分别给出了输出反馈和状态反馈H∞控制器的设计方法.通过引入变量代换,将... 详细信息

针对不确定线性系统,研究了执行器失效情况下鲁棒容错H∞控制问题.基于连续增益故障模式,利用线性矩阵不等式LMI推导了系统H∞指标约束下鲁棒容错镇定的充要条件,分别给出了输出反馈和状态反馈H∞控制器的设计方法.通过引入变量代换,将求解输出反馈H∞指标约束的鲁棒容错控制器的可解条件转化为标准的LMI.所获得的控制器不仅能使故障系统鲁棒稳定,并且能达到给定的H∞性能指标.仿真实例验证了所提出设计方法的有效性.

关键词：线性矩阵不等式鲁棒容错控制输出反馈状态反馈 H∞控制

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基于随机变环宽带的滞环电流控制策略

控制与决策 2014年第11期29卷 2061-2065页

作者：肖丽平童朝南北京联合大学北京市信息服务工程重点实验室北京100101 北京科技大学自动化学院北京100083

提出一种基于随机变环宽带的滞环电流控制策略.该策略是在固定的滞环带内增加一随机变环宽滞环带.调节电流变化率,以达到开关频率固定的目的.该方法利用开关的另一种状态得到补偿电流的误差信息,并给出变环宽带.由于随机函数的引入,使... 详细信息

提出一种基于随机变环宽带的滞环电流控制策略.该策略是在固定的滞环带内增加一随机变环宽滞环带.调节电流变化率,以达到开关频率固定的目的.该方法利用开关的另一种状态得到补偿电流的误差信息,并给出变环宽带.由于随机函数的引入,使得电流频谱分布拉宽,降低了谐波幅值和开关能耗.仿真结果验证了所提出控制策略的有效性.

关键词：有源滤波器随机滞环带固定开关频率变环宽控制开关损耗

基于Biswapped网络混合有效的负载均衡算法研究

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电子学报 2013年第8期41卷 1529-1535页

作者：童朝南孙丽婷北京科技大学自动化学院北京100083 北京科技大学钢铁流程先进控制教育部重点实验室北京100083

本文针对大型层次网络Biswapped Network(BSN),提出了一种简单有效的负载均衡策略CDE-X,克服了传统方案中因大规模层次网络复杂高阶的拉普拉斯矩阵特征值的计算而呈现的不适用性缺点.在新算法中,均衡迭代过程大部分发生在BSN的因子网络... 详细信息

本文针对大型层次网络Biswapped Network(BSN),提出了一种简单有效的负载均衡策略CDE-X,克服了传统方案中因大规模层次网络复杂高阶的拉普拉斯矩阵特征值的计算而呈现的不适用性缺点.在新算法中,均衡迭代过程大部分发生在BSN的因子网络内部,因而,CDE-X只需知道因子网络的结构及拉普拉斯特征值,从而在迭代均衡过程中提高了迭代收敛速度,并且降低了迁移负载流量的计算复杂性,同时降低了通信流量.理论比较证明,CDE-X不止降低了计算复杂性,更加降低了均衡迭代的步数,比传统的负载均衡策略X要更加简单、有效,更适用于大规模层次网络BSN.

关键词： Biswapped Network(BSN) 拉普拉斯矩阵特征值迭代

Clinical impact and mechanisms of hepatitis B virus infection concurrent with non-alcoholic fatty liver disease

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Chinese Medical Journal 2022年第14期135卷 1653-1663页

作者： Xin tong Yu Song Shengxia Yin Jian Wang Rui Huang chao Wu Junping Shi Jie Li Department of Infectious Diseases Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjingJiangsu 210008China Institute of Viruses and Infectious Diseases Nanjing UniversityNanjingJiangsu 210008China Department of Hepatology Zhejiang Chinese Medical UniversityHangzhouZhejiang 310053China Department of Hepatology The Affiliated Hospital of Hangzhou Normal UniversityHangzhouZhejiang 310015China

Chronic hepatitis B(CHB)virus infection is an important threat to global health despite the administration of vaccines and the use of antiviral treatments.In recent years,as the prevalence of obesity and metabolic syndrome has increased,non-alcoholic fatty liver disease(NAFLD)in patients with CHB has become more common.Both diseases can lead to liver fibrosis and even hepatocellular carcinoma,but the risk of dual etiology,outcome,and CHB combined with NAFLD is not fully elucidated.In this review,we assess the overlapping prevalence of NAFLD and CHB,summarize recent studies of clinical and basic research related to potential interactions,and evaluate the progressive changes of treatments for CHB patients with NAFLD.This review increases the understanding of the relationship and mechanisms of interaction between steatosis and hepatitis B virus infection,and it provides new strategies for the future clinical management and treatment of CHB combined with NAFLD.

关键词： Chronic hepatitis B Non-alcoholic fatty liver disease Steatosis Mechanism