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A model for predicting the segregation directions of binary Geldart B particle mixtures in bubbling fluidized beds

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Particuology 2024年第7期90卷 340-349页

作者： chenmin liu Yuemin Zhao Yanjiao li Yuqing Feng Chenlong Duan Chenyang Zhou liang Dong Key Laboratory of Coal Processing and Efficient Utilization Ministry of EducationChina University of Mining and TechnologyXuzhou221116China School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou221116China Mineral Resources Business Unit CSIROClaytonVIC 3169Australia

In gas fluidization processes involving different types of particles,the mixing or segregation behavior of the solid mixture is crucial to the overall outcome of the *** study develops a model to predict the segregation directions of binary mixtures of Geldart B particles with density and size differences in bubbling fluidized *** proposed model was established by combining the particle segregation model,a previous particle segregation model,with a derived bed voidage equation of the bubbling fluidization based on the two-phase *** model was then analyzed with different function graphs of the model equations under various *** results indicated that an increase in gas velocity or volume fraction of larger particles would strengthen size segregation,causing the larger and less dense components to *** validate the model,42 sets of data collected from 6 independent literature sources were compared with the predictions of the *** the gas velocities were below 3.2 times the minimum gas velocity,the predictions were consistent with experimental *** study has shed new light on the mechanisms of particle segregation in binary fluidized systems and provides a theoretical foundation for designing and manipulating gas-solid fluidized reactors.

关键词： Particle segregation Binary mixture Bubbling fluidization Geldart B particles Two-phase theory

Coupling Analysis of Disaster Bearing Capacity of Urban lifeline System Based on Brittleness Entropy

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Computational Water, Energy, and Environmental Engineering 2014年第3期3卷 119-127页

作者： Wei Huang Xinnan Zhang chenmin li Fengzhou Wang Zhenli Ma College of Computer and Information Engineering Hohai University Nanjing China College of Hydrology and Water Resources Hohai University Nanjing China

Urban or regional disaster bearing capacity mainly depends on the disaster bearing capacity of lifeline systems. In the analysis of disaster bearing capacity evaluation of lifeline system, we should not only investigate the complexity, balance and reliability of network characteristics, but also consider the relation between each subsystem. A new brittleness entropy of city disaster vulnerability associated coupling analysis method is proposed based on the brittleness of complex system theory. Correlation characteristics are reflected and evaluated in the brittle link entropy and the whole lifeline system, and then the vulnerability of city lifeline system can be quantified in flood scenarios. As a result of the coupling analysis and calculation, power system has the greatest effect among other subsystems. Because the key factors and influence of water supply system are uncertainties, the water supply system work or supply should be restored first after the disaster. The results show that the method can provide the basis for the optimization of system management, and control the repair work after disaster and coordination between subsystems.

关键词： Disaster Bearing Capacity lifeline System System Coupling Brittleness Entropy

A LEACH-Head Expected Frequency Appraisal Algorithm for Water-Environment Monitoring Networks

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International Journal of Communications, Network and System Sciences 2011年第9期4卷 562-567页

作者： chenmin li Guoping Tan Jingyu Wu Zhen Zhang lizhong Xu 不详

Water-environment monitoring network (WMN) is a wireless sensor network based real-time system, which collects, transmits, analyzes and processes water-environment parameters in large area. Both cluster selection mechanisms and energy saving strategies play an important role on designing network routing protocols for the WMN. Since those existing routing algorithms can not be used directly in the WMN, we thus propose an improved version of LEACH, a LEACH-Head Expected Frequency Appraisal (LEACH-HEFA) algorithm, for the WMN in this paper. Simulation results show that the LEACH-HEFA can balance the energy consumption of nodes, rationalize the clustering process and prolong the network lifetime significantly in the WMN. It indicates that the LEACH-HEFA is suitable to the WMN.

关键词： WSN LEACH Protocol Cluster-Head Selection Water-Environment Monitoring

High formability Mg-Zn-Gd wire facilitates ACL reconstruction via its swift degradation to accelerate intra-tunnel endochondral ossification

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Journal of Magnesium and Alloys 2024年第1期12卷 295-315页

作者： Xuan He Ye li Hongwei Miao Jiankun Xu Michael Tim-yun Ong chenmin Wang lizhen Zheng Jiali Wang Le Huang Haiyue Zu Zhi Yao Jie Mi Bingyang Dai Xu li Patrick Shu-hang Yung Guangyin Yuan ling Qin Musculoskeletal Research Laboratory of Department of Orthopaedics&Traumatology and Innovative Orthopaedic Biomaterial and Drug Translational Research Laboratory of li Ka Shing Institute of Health Sciences The Chinese University of Hong KongHong KongChina National Engineering Research Center of light Alloy Net Forming School of Materials Science&EngineeringShanghai Jiao Tong UniversityShanghaiChina Department of Orthopaedics and Traumatology Li Ka Shing Faculty of MedicineThe University of Hong KongHong KongChina Orthopaedic Department Peking University Third HospitalBeijingChina Department of Rehabilitation Sciences The Hong Kong Polytechnic UniversityHong KongChina

After reconstructing the anterior cruciate ligament(ACL),unsatisfactory bone tendon interface healing may often induce tunnel enlargement at the early healing *** good biological features and high formability,Magnesium-Zinc-Gadolinium(ZG21)wires are developed to bunch the tendon graft for matching the bone tunnel during ***,tensile strength,degradation,and cytotoxicity of ZG21 wire are *** rabbit model is used for assessing the biological effects of ZG21 wire by Micro-CT,histology,and mechanical *** SEM/EDS,immunochemistry,and in vitro assessments are performed to investigate the underlying *** tests demonstrate the high formability of ZG21 wire as surgical ***-CT shows ZG21 wire degradation accelerates tunnel bone formation,and histologically with earlier and more fibrocartilage regeneration at the healing *** mechanical test shows higher ultimate load in the ZG21 *** SEM/EDS presents ZG21 wire degradation triggered calcium phosphate(Ca-P)*** results demonstrate upregulation of Wnt3a,BMP2,and VEGF at the early phase and TGFβ3 and Type II collagen at the late phase of *** vitro tests also confirmed the Ca-P in the metal extract could elevate the expression of Wnt3a,βcatenin,ocn and opn to stimulate *** vivo tests of clinical samples indicated suturing with ZG21 wire did not weaken the ultimate loading of human tendon *** conclusion,the ZG21 wire is feasible for tendon graft *** degradation products accelerated intra-tunnel endochondral ossification at the early healing stage and therefore enhanced bone-tendon interface healing in ACL reconstruction.

关键词： Magnesium wire ACL reconstruction Magnesium alloy Biomaterials Endochondral ossification

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基于朴素贝叶斯算法的流域降水预测方法

水利水电科技进展 2016年第4期36卷 65-69,79页

作者：黄炜李雪真赵嘉赵丽华李臣民江苏省水文水资源勘测局江苏南京210029 河海大学计算机与信息学院江苏南京210098

为了在降水成因尚不明确的情况下有效利用相关历史资料提高降水预报水平,提出了基于朴素贝叶斯算法的流域降水预测方法。以东江流域为例,通过构造不同降水数据特征集预测流域内降水情况,并与传统时间序列方法和BP神经网络方法进行预测... 详细信息

为了在降水成因尚不明确的情况下有效利用相关历史资料提高降水预报水平,提出了基于朴素贝叶斯算法的流域降水预测方法。以东江流域为例,通过构造不同降水数据特征集预测流域内降水情况,并与传统时间序列方法和BP神经网络方法进行预测准确率对比验证,结果表明,基于朴素贝叶斯算法的降水预测方法取得了比传统时间序列方法和BP神经网络方法更好的降水预测效果。

关键词：降水预测朴素贝叶斯算法贝叶斯估计 F-measure评价方法

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基于全卷积编解码网络的视觉定位方法

测绘地理信息 2022年第6期47卷 46-49页

作者：李晨旻姚剑龚烨刘欣怡武汉大学遥感信息工程学院湖北武汉430079

针对目前视觉定位方法中使用人工特征的限制,提出了一种基于全卷积编解码网络的视觉定位方法。该方法将场景点3D坐标映射到图像的BGR(blue-green-red)通道,建立了图像到场景的直接联系,并通过全卷积编解码网络学习图像与场景结构的关系... 详细信息

针对目前视觉定位方法中使用人工特征的限制,提出了一种基于全卷积编解码网络的视觉定位方法。该方法将场景点3D坐标映射到图像的BGR(blue-green-red)通道,建立了图像到场景的直接联系,并通过全卷积编解码网络学习图像与场景结构的关系。给出一张图像,网络可以预测其每个像素点对应的3D点在当前场景世界坐标系的坐标;然后结合RANSAC(random sample consensus)和PnP(perspective-n-point)算法求解位姿并优化,得到最终的相对位姿。在7-Scenes数据集上的实验结果表明本文方法可实现厘米级的高精度定位,并且相比其他基于深度学习的方法,该方法在保证精度的同时,模型尺寸更小。

关键词：视觉定位场景构建姿态估计深度学习

半桥结构中的SiC MOSFET串扰电压建模研究

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中国电机工程学报 2020年第6期40卷 1775-1786页

作者：陈滢李成敏鲁哲别罗皓泽李楚杉李武华何湘宁浙江大学电气工程学院浙江省杭州市310027

SiC MOSFET凭借着低开关损耗、高工作频率与高工作温度点等优点,逐渐在高效率、高功率密度与高温的应用场合取代传统的硅功率器件。然而,在高速开关中带来的栅极串扰现象严重制约SiC器件的开关速度。传统的串扰抑制方法重点关注由栅极... 详细信息

SiC MOSFET凭借着低开关损耗、高工作频率与高工作温度点等优点,逐渐在高效率、高功率密度与高温的应用场合取代传统的硅功率器件。然而,在高速开关中带来的栅极串扰现象严重制约SiC器件的开关速度。传统的串扰抑制方法重点关注由栅极–漏极寄生电容引入的干扰电压,往往通过减小驱动回路阻抗的方式来降低串扰电压。该文基于SiC MOSFET器件的开关模态,提出考虑共源电感的分段线性化串扰电压模型。该模型基于器件数据手册及双脉冲实验提取的参数,考虑栅极–漏极电容、共源电感、体二极管反向恢复等非理想因素的影响。对比不同电压点、电流点与电阻值下实验与模型的输出结果。该模型表明,串扰电压是由器件栅极–漏极电容、共源电感与驱动回路阻抗共同作用的结果。单一降低驱动回路阻抗的方式对串扰电压的抑制效果有限。基于提出的模型,该文给出串扰电压抑制的指导方法,可直接用于SiC MOSFET驱动电路的设计。

关键词： SiC MOSFET 串扰共源电感 SiC驱动

颞叶癫痫伴双侧海马硬化与单侧海马硬化的临床特征差异分析

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中华神经医学杂志 2024年第5期23卷 450-457页

作者：陶琪何晨敏邱晶晶杨育育徐莎郭谊李宏丁瑶丁美萍王爽浙江大学医学院附属第二医院神经内科杭州310009 浙江大学医学院附属第二医院放射科杭州310009 湖州市中心医院神经内科湖州313000

目的探讨颞叶癫痫伴双侧海马硬化(TLE-bHS)与颞叶癫痫伴单侧海马硬化(TLE-uHS)临床特征的差异。方法回顾性纳入浙江大学医学院附属第二医院神经内科癫痫中心自2013年1月至2022年1月收治的48例明确诊断为TLE-bHS且临床资料完整的患者(TLE... 详细信息

目的探讨颞叶癫痫伴双侧海马硬化(TLE-bHS)与颞叶癫痫伴单侧海马硬化(TLE-uHS)临床特征的差异。方法回顾性纳入浙江大学医学院附属第二医院神经内科癫痫中心自2013年1月至2022年1月收治的48例明确诊断为TLE-bHS且临床资料完整的患者(TLE-bHS组),以及同期收治的101例明确诊断为TLE-uHS且临床资料完整的患者(TLE-uHS组),分析2组患者的临床资料如发病年龄、病程、既往病史、癫痫发作频率、抗发作药物种类、视频脑电图结果、神经心理测试结果以及治疗结局等方面的差异。结果与TLE-uHS组相比,TLE-bHS组患者男性占比更高,发病年龄更晚,病程更短,癫痫发作频率更高,既往及现用抗发作药物种类更多,癫痫发作时自主神经先兆比例更低、无先兆比例更高,视频脑电图中后头部背景活动偏慢比例更高,记忆商数、言语记忆评分及非言语记忆评分更低,差异均有统计学意义(P<0.05)。另外,2组患者既往病史构成比、发作间期癫痫样异常分布区域构成比的差异亦均有统计学意义(P<0.05),其中TLE-bHS组既往常伴有颅内感染/脑炎史,双侧颞区癫痫样异常比例更高;而TLE-uHS组常伴有热性惊厥史,单侧颞区癫痫样异常比例更高。TLE-bHS组患者中仅10例(20.8%)接受了非药物治疗,包括前颞叶切除手术3例(术后随访2年均为Engel分级Ⅰ级)、神经调控治疗4例、生酮饮食治疗4例;TLE-uHS组患者中55例(54.5%)接受了前颞叶切除手术,术后随访2年时Engel分级Ⅰ级48例(87.3%)、Ⅱ级1例(1.8%)、Ⅲ级4例(7.3%)、Ⅳ级2例(3.6%)。结论TLE-bHS患者与TLE-uHS患者在性别、既往病史、发病年龄、病程、癫痫发作频率、抗发作药物种类、视频脑电图、神经心理测试等方面的差异有助于将两者相鉴别。

关键词：颞叶癫痫双侧海马硬化单侧海马硬化

复杂条件下雅万高铁帕达拉朗车站施工组织技术

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中国铁路 2023年第12期 20-28页

作者：魏强张民栓张立新周发恒梁生武李辰旻李海峰王重秋中国国家铁路集团有限公司工程管理中心北京100844 中铁三局集团有限公司山西太原030001 中铁三局集团建筑安装工程有限公司山西太原030006

雅万高铁新建帕达拉朗(Padalarang)车站,面临工期紧张、施工场地受限、临近既有线施工安全风险高、结构复杂难度大、施工资源组织困难等问题,通过科学合理安排施工组织、精确划分施工区段和作业顺序,强化施工资源保障,同时采取大跨度钢... 详细信息

雅万高铁新建帕达拉朗(Padalarang)车站,面临工期紧张、施工场地受限、临近既有线施工安全风险高、结构复杂难度大、施工资源组织困难等问题,通过科学合理安排施工组织、精确划分施工区段和作业顺序,强化施工资源保障,同时采取大跨度钢桁架跨营业线分段吊装施工技术、受限作业空间高铁站房逆作法施工技术、屋面弧形曲面檐口铝板安装技术等关键技术方案,按期完成了车站施工任务,可为类似复杂条件下海外铁路客站建设提供参考。

关键词：雅万高铁帕达拉朗车站施工组织分段吊装逆作法

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