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冲击磨损下团球状共晶体奥-贝钢磨损表面层组织的变化

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摩擦学学报 1999年第1期19卷 39-44页

作者：许振明姜启川孙宝德何镇明周尧和上海交通大学铸造研究所吉林工业大学

采用ＭＬＤ－１０型磨损试验机、扫描电镜和透射电镜等研究了冲击磨损条件下团球状共晶体奥－贝钢磨损表面组织的变化．结果表明：奥－贝钢的冲击磨损表层中存在非晶态组织和纳米级晶粒；磨损亚表层中存在大量位错马氏体和形变贝氏体组... 详细信息

采用ＭＬＤ－１０型磨损试验机、扫描电镜和透射电镜等研究了冲击磨损条件下团球状共晶体奥－贝钢磨损表面组织的变化．结果表明：奥－贝钢的冲击磨损表层中存在非晶态组织和纳米级晶粒；磨损亚表层中存在大量位错马氏体和形变贝氏体组织；奥－贝钢从亚表层到磨损表面方向的硬度逐渐增加，具有梯度分布特征，能够有效抵抗磨料的冲击和凿削作用，同时磨损亚表层中的位错、形变马氏体和贝氏体组织具有很好的强韧性匹配，可抑制高冲击下微裂纹的形成，因此奥－贝钢的抗磨料磨损性能良好．

关键词：冲击磨损非晶态组织纳米级晶粒 ANBE钢钢

Tube Model Predictive Control Based Cyber-attack-resilient Optimal Voltage Control Strategy in Wind Farms

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 530-538页

作者： zhenming Li Minghao Wang Yunfeng Yan Donglian Qi Zhao Xu Jianliang Zhang Zezhou Wang College of Electrical Electronic Engineering Zhejiang UniversityHangzhou 310058China Department of Electrical Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina Haiyan power supply company of State Grid Zhejiang Electric Power Co. LtdHangzhouChina

Optimal voltage controls have been widely applied in wind farms to maintain voltage stability of power *** order to achieve optimal voltage operation,authentic grid information is widely needed in the sensing and actuating ***,this may induce system vulnerable to malicious *** this end,a tube model predictive control-based cyber-attack-resilient optimal voltage control method is proposed to achieve voltage stability against malicious *** proposed method consists of two cascaded model predictive controllers(MPC),which outperform other peer control methods in effective alleviation of adverse effects from cyber-attacks on actuators and sensors of the ***,efficiency of the proposed method is evaluated in sensor and actuator cyber-attack cases based on a modified IEEE 14 buses system and IEEE 118 buses *** Terms-Attack-resilient control,optimal voltage control,tube-based model predictive control,wind farm-connected power system.

关键词： Attack-resilient control optimal voltage control tube-based model predictive control wind farm-connected power system

离心加速场中金属凝固过程温度场分布数值分析

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复合材料学报 2001年第2期18卷 75-80页

作者：张新平于思荣何镇明吉林大学南岭校区材料科学与工程学院长春130025

采用有限差分法及 Math Cad软件首次模拟了二维柱坐标系下自硬砂型离心铸造凝固过程 ,并就转速、浇温、铸型预热温度、铸型类别等工艺参数对铸件温度场分布的影响规律进行了研究。模拟结果表明 ,由于采用自硬砂型和灰铁盖 ,铸件的上下... 详细信息

采用有限差分法及 Math Cad软件首次模拟了二维柱坐标系下自硬砂型离心铸造凝固过程 ,并就转速、浇温、铸型预热温度、铸型类别等工艺参数对铸件温度场分布的影响规律进行了研究。模拟结果表明 ,由于采用自硬砂型和灰铁盖 ,铸件的上下表面首先凝固 ,然后逐渐向金属液中间推进 ;随转速、铸型蓄热系数的增加 ,铸型预热温度与浇注温度的降低 ,金属凝固加快 ;在其它条件相同的情况下 ,型温对温度场的影响最大 ,转速其次。

关键词：离心加速场凝固梯度功能材料数值分析离心铸造制备金属温度场分布

基于B/S架构的GIS专业文献资料管理系统的设计与实现

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中国科技论文 2016年第9期11卷 1067-1072页

作者：崔海福何贞铭长江大学地球科学学院武汉430100

为了解决传统通用文献管理系统无法满足GIS用户专业化、个性化需求等问题,设计并开发了以B/S(Browser/Server)为系统架构存储GIS专业文献资料的管理系统,实现了文献的浏览、下载、评论等基本功能,创建管理文献的公共文献库和个人文献库... 详细信息

为了解决传统通用文献管理系统无法满足GIS用户专业化、个性化需求等问题,设计并开发了以B/S(Browser/Server)为系统架构存储GIS专业文献资料的管理系统,实现了文献的浏览、下载、评论等基本功能,创建管理文献的公共文献库和个人文献库,开发对文献和用户分析的统计功能,并建立方便对系统用户、权限、数据库管理的系统管理模块,其中运用AJAX和Highcharts等技术来提升系统效率和用户体验。将GIS专业文献进行统一的管理,不仅可以方便专业用户的使用,还可对运用GIS技术的不同领域的发展做出预测分析。

关键词： B/S GIS 文献资料管理系统 AJAX

Distributed Event-triggered Control for Frequency Restoration in Islanded Microgrids with Reduced Trigger Condition Checking

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 2156-2165页

作者： Yulin Chen Donglian Qi zhenming Li Zhenyu Wang Xinyi Yang Jianliang Zhang College of Electrical Engineering Zhejiang UniversityHangzhou 310027China

For islanded microgrids(MGs),distributed control is regarded as a preferred alternative to centralized control for the frequency restoration of ***,distributed control with successive communication restricts the efficiency and resilience of the control *** address this issue,this paper proposes a distributed event-triggered control strategy for the frequency secondary control in islanded *** proposed event-triggered control is Zeno behavior free and enables each DG to update and propagate its state to neighboring DGs only when a specific“event”occurs,which significantly reduces the communication *** with the existing event-triggered control,a trigger condition checking period of the proposed event-triggered control is provided to reduce the computation burden when checking the trigger ***,using the aperiodicity and intermittent properties of the communication,a simple detection principle is proposed to detect and isolate the compromised communication links in a timely and economic fashion,which improves the resilience of the system against FDI ***,the control effectiveness of the proposed control scheme is validated by the simulation results of the tests on an MG with 4 DGs.

关键词： Distributed control event-triggered control islanded microgrid secondary control

ZA22/Al_2O_3短纤维复合材料高温拉伸行为的理论分析

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复合材料学报 1998年第3期15卷 17-20页

作者：于思荣何镇明任露泉吉林工业大学铸造教研室

采用日本产ＡＧ－１０ＴＡ型电子万能试验机对挤压铸造ＺＡ２２／Ａｌ２Ｏ３短纤维复合材料的高温抗拉强度进行了测定，并用Ｆｒｉｅｎｄ修正的混合律模型对该试验结果进行了理论分析，结果表明ＺＡ２２／Ａｌ２Ｏ３短纤维复合材料及其... 详细信息

采用日本产ＡＧ－１０ＴＡ型电子万能试验机对挤压铸造ＺＡ２２／Ａｌ２Ｏ３短纤维复合材料的高温抗拉强度进行了测定，并用Ｆｒｉｅｎｄ修正的混合律模型对该试验结果进行了理论分析，结果表明ＺＡ２２／Ａｌ２Ｏ３短纤维复合材料及其基体的强度均随温度升高而下降，但ＺＡ２２合金基体的强度下降幅度更大。任一纤维体积分数的复合材料，均存在一临界转变温度Ｔｃｒｉｔ；超过该温度，复合材料强度大于基体强度。纤维体积分数越大，所需临界转变温度越低。在本试验中，Ｖｆ为１５％和２０％的复合材料的Ｔｃｒｉｔ分别为１２３℃和８７℃。任一温度下，复合材料均存在一临界纤维体积分数，超过该纤维体积分数，复合材料强度高于基体强度。温度越高，临界纤维体积分数越低。对ＺＡ２２／Ａｌ２Ｏ３短纤维复合材料来说，Ｆｒｉｅｎｄ模型中的经验参数Ｃ＊的取值随温度升高而降低。

关键词： ZA22 金属基复合材料高温抗拉强度短纤维增强

Self-calibrating microring synapse with dual-wavelength synchronization

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Photonics Research 2023年第2期11卷 347-356页

作者： JUNWEI CheNG zhenming he YUHAO GUO BO WU HAILONG ZHOU TEYAN CheN YIXIN WU WENWEI XU JIANJI DONG XINLIANG ZHANG Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Optics Valley Laboratory Wuhan 430074China Galileo Advanced Technology Lab Huawei TechnologiesShenzhen 518129China Institute of Strategic Research Huawei TechnologiesShenzhen 518129China

As a resonator-based optical hardware in analog optical computing, a microring synapse can be straightforwardly configured to simulate the connection weights between neurons, but it faces challenges in precision and stability due to cross talk and environmental perturbations. here, we propose and demonstrate a self-calibration scheme with dual-wavelength synchronization to monitor and calibrate the synaptic weights without interrupting the computation tasks. We design and fabricate an integrated 4 × 4 microring synapse and deploy our self-calibration scheme to validate its effectiveness. The precision and robustness are evaluated in the experiments with favorable performance, achieving 2-bit precision improvement and excellent robustness to environmental temperature fluctuations(the weights can be corrected within 1 s after temperature changes 0.5°C). Moreover, we demonstrate matrix inversion tasks based on Newton iterations beyond 7-bit precision using this microring synapse. Our scheme provides an accurate and real-time weight calibration independently parallel from computations and opens up new perspectives for precision boost solutions to large-scale analog optical computing.

关键词： synchronization microring resonator

Inverting the rock mass P-wave velocity field ahead of deep buried tunnel face while borehole drilling

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International Journal of Mining Science and Technology 2024年第5期34卷 681-697页

作者： Liu Liu Shaojun Li Minzong Zheng Dong Wang Minghao Chen Junbo Zhou Tingzhou Yan zhenming Shi State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China China Railway Eryuan Engineering Group CO. LTD.Chengdu 610031China Department of Hydraulic and Hydropower Engineering Tsinghua UniversityBeijing 100084China Hubei Communications Planning and Design Institute CO. LTD.Wuhan 430051China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China

Imaging the wave velocity field surrounding a borehole while drilling is a promising and urgently needed approach for extending the exploration range of the borehole *** paper develops a drilling process detection(DPD)system consisting of a multifunctional sensor and a pilot geophone installed at the top of the drilling rod,geophones at the tunnel face,a laser rangefinder,and an onsite computer.A weighted adjoint-state first arrival travel time tomography method is used to invert the P-wave velocity field of rock mass while borehole drilling.A field experiment in the ongoing construction of a deep buried tunnel in southwestern China demonstrated the DPD system and the tomography ***-frequency analysis of typical borehole drilling detection data shows that the impact drilling source is a pulse-like seismic exploration wavelet.A velocity field of the rock mass in a triangular area defined by the borehole trajectory and geophone receiving line can be *** the borehole core and optical image validate the inverted P-wave velocity field.A numerical simulation of a checkerboard benchmark model is used to test the tomography *** rapid convergence of the misfits and consistent agreement between the inverted and observed travel times validate the P-wave velocity imaging.

关键词： Deep buried tunnel Wave velocity field Borehole drilling Tomography Rock mass

具有粒状碳化物的莱氏体型铸造模具钢的耐磨性研究

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摩擦学学报 1999年第1期19卷 33-38页

作者：王树奇姜启川隋学民何镇明吉林工业大学材料科学与工程学院

研制了含粒状碳化物的新型莱氏体型铸造模具钢，发现其可使传统莱氏体型铸造模具钢的低强韧性得以提高，并探讨了其磨损机理．结果表明，碳化物形态（大小、形貌、分布及数量）对莱氏体钢的耐磨性有明显影响．由于该新型铸造模具钢有沿... 详细信息

研制了含粒状碳化物的新型莱氏体型铸造模具钢，发现其可使传统莱氏体型铸造模具钢的低强韧性得以提高，并探讨了其磨损机理．结果表明，碳化物形态（大小、形貌、分布及数量）对莱氏体钢的耐磨性有明显影响．由于该新型铸造模具钢有沿枝晶间均匀分布、形貌圆整的１次碳化物和晶内弥散析出的大量２次碳化物，其耐磨性略高于相近碳化物形态的锻造３～４级偏析Ｃｒ１２类钢，明显高于锻造１～２级偏析Ｃｒ１２类钢和传统莱氏体型铸造模具钢．

关键词：莱氏体钢铸造模具粒状碳化物耐磨性模具钢