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Acta Mechanica Solida Sinica 2023年第2期36卷 327-339页

作者： Mingzhi Wang guitao zhang Tingguang Liu Weidong Wang School of Mechano-Electronic Engineering Xidian UniversityXi’an 710071China CityU-Xidian Joint Laboratory of Micro/Nano Manufacturing Shenzhen 518057China National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China

The instrumented nanoindentation technique has been widely used to measure the tensile properties of various materials,for its simple specimen preparation and nearly nondestructive testing *** this paper,a novel inverse method is established for measuring the elastoplastic properties of Al 2024 *** grid indentation experiments are performed on Al 2024 *** obtained experimental load–displacement(P–h)data exhibit obvious scatter *** artificial neural network(ANN)model with tunable hyper-parameters is adopted to establish the forward relationship between elastoplastic parameters and indentation load–displacement *** objective function for quantifying the error norm between predicted and experimental P–h snapshots is *** parameter identification problem is solved using the“interior-point”constraint optimization algorithm..The identified material properties show good agreement with the tensile data,and the error values are−8.66%for elastic modulus,1.08%for yield stress,and 6.90%for hardening *** sensitivity of numerical results to experimental uncertainty is analyzed,and the error bound of experimental data is *** results of sensitivity analysis indicate that the proposed inverse method in the work is very effective and reliable.

关键词： Nanoindentation Material properties Al 2024 alloy Deep learning Parameter identification

Closed-loop supply chain network equilibrium strategy model with environmental protection objectives

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Chinese Journal of Population,Resources and Environment 2020年第3期18卷 251-261页

作者： Yang Liu guitao zhang Qingdao University Qingdao266071China

With the increasing popularity of ecological civilization and sustainable development,enterprises should consider environmental protection measures in their operations in addition to pursue their economic *** paper establsihes a closed-loop supply chain network model composed of multiple suppliers,manufacturers,retailers,recyclers,and demand markets—regarding their dual goals of the profit maximization and the minimization of carbon *** conditions necessary for establishing overall equilibrium and an equilibrium model of the entire closed-loop supply chain network are determined by applying variational inequality and dual theory.A modified projection contraction algorithm is used to design a model-solving ***,using numerical examples,the paper conducts a comparative static analysis on important parameters such as the weight coefficients of environmental protection objectives and consumers'awareness of low-carbon environmental protection and attains some beneficial enlightenment on *** results indicate that when the environmental protection objectives of a certain type of enterprise increases,both the economic benefits and environmental protection performance will improve;when the environmental protection objectives of all enterprises increases simultaneously,environmental protection performance improves significantly,but the changes in economic benefits of different enterprises are inconsistent and profit coordination is more *** consumers’awareness of low-carbon preference could improve environmental performance,it reduces the overall profits of network members and the entire closed-loop supply chain network as a *** above conclusions can be used as a reference for the government in designing low-carbon environmental protection policy and in closed-loop supply chain research.

关键词： Closed-loop supply chain network Environmental protection objectives Nash equilibrium Multi-objective decision-making Environmental protection awareness of consumers

Childhood strokes in China describing clinical characteristics, risk factors and performance indicators: a case-series study

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Stroke & Vascular Neurology 2022年第2期7卷 140-148页

作者： Yaxian Deng Gaifen Liu guitao zhang Juanyu Xu Chunmei Yao Lei Wang Chengsong Zhao Yongjun Wang Department of Pediatrics Beijing Tiantan Hosppital Affiliated to Capital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Disease BeijingChina Department of Neurology Beijing Tiantan Hosppital Affiliated to Capital Medical UniversityBeijingChina Outpatient Department Beijing Children’s Hospital Affiliated to Capital Medical UniversityBeijingChina

Aim To investigate clinical characteristics,risk factors(RFs),neurologic deficits and medical care provided in children who had a stroke in *** We conducted a retrospective case-series study using the medical records of children aged 1 month to 18 years with arterial ischaemic stroke(AIS)or haemorrhagic stroke(HS)(with the entry codes I60,I61,I62,I63(ICD-10)),who were admitted to different hospitals in Beijing,between January 2018 and December *** obtained the following information from the charts:demographic characteristics,clinical presentations,RFs for paediatric stroke,laboratory examination,neuroimaging records and neurologic *** We identified 312 first admissions for stroke(172 AIS and 140 HS).The mean age at onset was 8.6±3.9 years for patients who had an AIS and 8(5–13)years for patients who had an *** were more males than females in both groups(AIS:59.88%vs 40.12%;HS:52.14%vs 47.86%).A known aetiology was identified in 92.44%and 86.43%of patients who had an AIS and HS,*** leading cause of AIS was cerebrovascular diseases including moyamoya(68.6%),while that for HS was arteriovenous malformation(51.43%).The most common initial clinical presentation was hemiplegia(86.05%)in patients who had an AIS and headache(67.86%)in patients who had an *** use of healthcare,including acute treatment(antithrombotic in 17.44%,anticoagulant in 5.23%)and secondary prevention(antithrombotic in 6.39%,anticoagulant in 1.16%),varied and was significantly lower among patients who had an *** most common complications were epilepsy(22.09%)and pneumonia(4.65%)in patients who had an AIS and epilepsy(17.14%)and hydrocephalus(12.14%)in patients who had an *** deficits occurred in 62.8%of patients who had an AIS and 72.86%of patients who had an *** Cerebral arteriopathy was a major RF for both AIS and HS in children living in *** epidemiological studies are required to identify RFs to prevent stroke as well

关键词： epilepsy clinical admitted

Chinese Stroke Association guidelines for clinical management of ischaemic cerebrovascular diseases:executive summary and 2023 update

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Stroke & Vascular Neurology 2023年第6期8卷 I0087-I0133页

作者： Liping Liu Zixiao Li Hongyu Zhou Wanying Duan Xiaochuan Huo Weihai Xu Shujuan Li Ximing Nie Huihui Liu Jinjie Liu Dapeng Sun Yufei Wei guitao zhang Weizhuang Yuan Lina Zheng Jingyi Liu David Wang Zhongrong Miao Yongjun Wang Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina National Center for Healthcare Quality Management in Neurological Diseases BeijingChina Research Unit of Artificial Intelligence in Cerebrovascular Disease Chinese Academy of Medical SciencesBeijingChina Chinese Institute for Brain Research BeijingChina Neurological Disease Center Cerebral Vascular Disease DepartmentBeijing Anzhen HospitalCapital Medical UniversityBeijingChina Department of Neurology State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Neurology National Clinical Research Center for Cardiovascular DiseasesFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Neurology and Suzhou Clinical Research Center of Neurological Disease the Second Affiliated Hospital of Soochow UniversitySuzhouChina Department of General Medicine Dalian Municipal Central Hospital Affiliated Dalian University of TechnologyDalianChina Interventional Neuroradiology Department of NeurologyBeijing Tiantan HospitalCapital Medical UniversityBeijingChina Neurovascular Division Department of NeurologyBarrow Neurological InstituteSt.Joseph's Hospital and Medical CenterPhoenixArizonaUSA Advanced Innovation Center for Human Brain Protection Capital Medical UniversityBeijingChina

Background China is one of the countries with the highest burden of *** multidimensional management guidelines will help clinicians practise evidence-based care,improve patient outcomes and alleviate societal *** update of the 2019 edition will provide the latest comprehensive recommendations for the diagnosis and treatment of ischaemic cerebrovascular *** We conducted a comprehensive search on MEDLINE(via PubMed)up to 31 August *** writing team established the recommendations through multiple rounds of online and offline *** recommendation was graded using the evidence grading algorithm developed by the Chinese Stroke Association(CSA).The draft was reviewed and finalised by the CSA Stroke Guidelines Writing *** This update included revisions of 15 existing recommendations and 136 new recommendations in the following areas of stroke care:emergency assessment and diagnosis of ischaemic cerebrovascular disease,acute-phase reperfusion therapy,evaluation of underlying mechanisms,antithrombotic therapy,prevention and treatment of complications,and risk factor *** This guideline updated the recommendations for the clinical management of ischaemic cerebrovascular disease from 2019.

关键词： diagnosis prevention discussions

Linear and Nonlinear Ultrasonic Detections of Impact Damage in Composite Laminate

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第5期41卷 599-608页

作者： WANG Rong WU Qi zhang guitao XIA Guochun Business College Qingdao UniversityQingdao 266071P.R.China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China Jiangsu Runhua Cable Shareholding Co.Ltd. Yangzhou 225613P.R.China

The appearance and accumulation of internal impact damage seriously influence overall performance of carbon fiber reinforced plastic(CFRP).Thus,this study evaluates the change in impact damage number by using linear and nonlinear ultrasonic Lamb wave detection methods,and compares these two detection *** ultrasonic wave simulation model for composite structure with impact damage is established using the finite element method,and the interaction between impact damage and the ultrasonic wave is *** results demonstrate that the ultrasonic amplitude linearly decreases,and the relative nonlinear parameter linearly increases in proportion to the impact number,*** linear-fitting slope of nonlinear parameter is 0.38 per impact number at an input frequency of 1.0 *** is far higher than that of the linear ultrasonic amplitude,which is ***,with the increase of impact damage,the linear growth of nonlinear parameters mainly depends on the decrease in ultrasonic amplitude rather than the accumulation of second harmonic *** the linear ultrasonic amplitude detection,the linear fitting slope at 1.1 MHz is-0.14,which is lower than those at 0.9 MHz and 1.0 ***,in the nonlinear ultrasonic parameter detection,the linear fitting slope at 1.1 MHz is 0.92,which is higher than those at 0.9 MHz and 1.0 *** results show that higher frequencies lead to greater attenuation of ultrasonic amplitude and a larger increase in nonlinear parameters,which can enhance the sensitivity of both linear and nonlinear ultrasonic *** accuracy of simulation results is demonstrated through the low-velocity impact and ultrasonic *** results show that compared with nonlinear ultrasonic technology,the linear ultrasonic technology is more suitable for impact damage assessment of carbon fiber reinforced plastic because of its simpler detection process and higher sensitivity.

关键词： carbon fiber reinforced plastic(CFRP) nonlinear ultrasonic Lamb wave impact damage nondestructive testing

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基于贝叶斯理论的氯离子扩散系数计算模型

西安建筑科技大学学报（自然科学版） 2019年第5期51卷 710-716页

作者：罗大明张桂涛西安建筑科技大学土木工程学院陕西西安710055 西部绿色建筑国家重点实验室陕西西安710055

氯离子侵蚀引起的钢筋锈蚀是沿海或者盐湖地区混凝土结构耐久性劣化的主要诱因,现有氯离子侵蚀模型中的扩散系数多基于Fick’s第二定律,由实验室试验或工程测试确定,具有一定的局限性.基于氯离子扩散系数试验数据,采用贝叶斯理论,建立... 详细信息

氯离子侵蚀引起的钢筋锈蚀是沿海或者盐湖地区混凝土结构耐久性劣化的主要诱因,现有氯离子侵蚀模型中的扩散系数多基于Fick’s第二定律,由实验室试验或工程测试确定,具有一定的局限性.基于氯离子扩散系数试验数据,采用贝叶斯理论,建立了氯离子扩散系数计算模型.该模型综合考虑了水胶比、侵蚀时间、环境温度、相对湿度等因素对氯离子扩散系数的影响,能较好地反映氯离子扩散系数的变化情况.通过已有试验数据验证表明,该模型的计算结果与试验结果吻合较好,具有一定的理论和应用价值.

关键词：氯离子扩散系数贝叶斯理论 Fick’s第二定律混凝土耐久性

考虑消费者渠道偏好的多期闭环供应链网络均衡

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系统工程理论与实践 2016年第2期36卷 347-362页

作者：张桂涛胡劲松王磊孙浩 MAZALOV V 青岛大学管理科学与工程学院青岛266071 俄罗斯科学院彼得罗扎沃茨克185910

在多个规划期情形下,研究了由制造商层、零售商层、需求市场层和回收商层组成的闭环供应链网络均衡问题.所有制造商生产同质产品,利用双渠道分销产品以满足市场需求.两种交易渠道间存在竞争,消费者对电子商务和零售商两种购物渠道存在... 详细信息

在多个规划期情形下,研究了由制造商层、零售商层、需求市场层和回收商层组成的闭环供应链网络均衡问题.所有制造商生产同质产品,利用双渠道分销产品以满足市场需求.两种交易渠道间存在竞争,消费者对电子商务和零售商两种购物渠道存在不同偏好.利用变分不等式和互补理论刻画了网络中各成员的最优经济行为,建立了供应链网络均衡模型,并运用修正投影收缩算法求解.结合算例探讨了单/双渠道、渠道间的竞争强度因子、消费者对电子商务渠道的偏好系数及制造商的强制回收量约束对供应链网络各成员及网络均衡的影响.结果表明:当消费者偏好大于一定程度时,双渠道对制造商有利,而对零售商不利;电子渠道竞争强度因子对网络成员的利润影响较大,制造商应加大网络等方面投资;当消费者对电子交易渠道的偏好增加时,制造商利润先减后增,制造商在开设电子商务时应把握合适的切入时机,且不要因暂时的利润降低而关闭电子营销方式;单/双渠道情形下,政府的强制性回收量约束均会对制造商带来不利影响,当回收量约束超过某一值时所有成员会动态调整其策略而改变供应链网络的均衡状态.通过研究,以期对闭环供应链相关领域的研究和企业决策有一定借鉴.

关键词：闭环供应链网络均衡多期双渠道消费者偏好

港口供应链中分配公平关切和对等公平关切对订单分配的影响

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上海海事大学学报 2020年第4期41卷 55-62页

作者：陈东辉张桂涛青岛大学商学院山东青岛266071

为研究港口供应链中公平关切对订单分配的影响,针对由一个港口企业与两个依次参与分配竞争的港口业务服务商组成的二级港口供应链,构建考虑分配公平关切和对等公平关切的博弈模型。运用博弈论分析公平关切对港口供应链订单分配的影响。... 详细信息

为研究港口供应链中公平关切对订单分配的影响,针对由一个港口企业与两个依次参与分配竞争的港口业务服务商组成的二级港口供应链,构建考虑分配公平关切和对等公平关切的博弈模型。运用博弈论分析公平关切对港口供应链订单分配的影响。研究表明:港口企业的最优效用会随第二个港口业务服务商的对等公平关切增加,随当前港口业务服务商的分配公平关切减少。港口企业期望港口业务服务商具有更多的对等公平关切和较少的分配公平关切,故提出一种协调机制,当参数满足一定条件时可以提高港口企业的效用。

关键词：港口供应链订单分配分配公平关切对等公平关切博弈论

区块链技术下考虑公平关切的竞争性供应链定价及协调策略

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经济与管理评论 2024年第5期40卷 122-134页

作者：林帅成张桂涛青岛大学商学院山东青岛266100

为探究区块链技术背景下竞争性供应链的最优决策,考虑由两个具有竞争性制造商和一个零售商组成的二级供应链,其中制造商均具有双向公平关切行为,讨论供应链的最优定价及协调策略。研究发现:制造商的横向和纵向公平关切行为对供应链上下... 详细信息

为探究区块链技术背景下竞争性供应链的最优决策,考虑由两个具有竞争性制造商和一个零售商组成的二级供应链,其中制造商均具有双向公平关切行为,讨论供应链的最优定价及协调策略。研究发现:制造商的横向和纵向公平关切行为对供应链上下游利润的影响趋势相反,过度的公平关切行为会损害供应链的利润;企业需要根据消费者对产品真实的敏感性高低来选择是否引入区块链技术;在区块链技术普及率较低时,消费者会以较低的价格购买到区块链技术支持的产品,该产品需要以低价优势打开市场;收益共享契约和两部定价契约都能使供应链达到协调状态,而两部定价契约的适配性更好。

关键词：区块链技术竞争性供应链双向公平关切协调

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考虑产品寿命次数的多期闭环供应链网络均衡

信息与控制 2015年第1期44卷 29-37页

作者：张桂涛胡劲松孙浩戴更新青岛大学管理科学与工程系山东青岛266071

在考虑产品寿命次数的基础上,研究了由多个制造商和多个消费市场组成的闭环供应链网络的多期动态均衡问题.采用变分不等式和互补理论获得了制造商和消费市场的最优性条件,进而建立了整个闭环供应链网络的均衡模型.采用定步长的修正投影... 详细信息

在考虑产品寿命次数的基础上,研究了由多个制造商和多个消费市场组成的闭环供应链网络的多期动态均衡问题.采用变分不等式和互补理论获得了制造商和消费市场的最优性条件,进而建立了整个闭环供应链网络的均衡模型.采用定步长的修正投影收缩算法对模型进行求解,通过算例将不同寿命次数结合有关参数对网络均衡状态的影响进行了对比分析,给出了政府有关部门和供应链网络中制造商作决策时需关注的关键问题,本文所得结论为开展相关领域的研究提供一定的借鉴.

关键词：闭环供应链网络产品寿命次数回收率再制造