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Investigation on insulation properties of HFO-1336mzz(E)and N_(2)/CO_(2)mixtures as SF_(6) substitutes in gas-insulated electrical applications

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High Voltage 2023年第1期8卷 48-58页

作者： Zhanyang Gao Yunbai Luo ruichao peng Xiaoxiao Wang Ping Yu Wenjun Zhou Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhanChina School of Electrical Engineering and Automation Wuhan UniversityWuhanChina

The emissions of SF6 have been restricted owing to 3400 years of atmospheric lifetime and high global warming potential(GWP)as an insulating gas in gas-insulated electrical equipment.In this study,HFO-1336mzz(E)and N_(2)/CO_(2)mixtures are proposed as SF6 substitutes for their short atmospheric lifetime,low GWP and superior insulation performance.The GWP of HFO-1336mzz(E)is only 18 and its atmospheric lifetime is days to weeks.The breakdown voltage of 25%HFO-1336mzz(E)and N_(2)/CO_(2)mixtures is about 85%that of pure SF6 under alternating current.The self-recovery ability of HFO-1336mzz(E)and CO_(2)mixtures is superior to that of HFO-1336mzz(E)and N_(2)mixtures.The decomposition characteristic of HFO-1336mzz(E)shows that a tiny amount of its gas might initiate a carbonisation reaction to form carbon after multiple breakdown tests,which is verified by observations using energy dispersive X-rays spectroscopy and scanning electron microscope.The acute toxicity test of HFO-1336mzz(E)indicates that the gas is non-toxic.The results show that HFO-1336mzz(E)and N_(2)/CO_(2)mixtures are potential substitutes for SF6 in electrical applications.

关键词： SF6 electrical insulation

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电力变压器环保绝缘油研究进展与趋势

南方电网技术 2024年第5期18卷 12-21,30页

作者：马秉伟陈晓国郑宇刘凯陶子林彭瑞超王宝山袁佳歆广东电网有限责任公司肇庆供电局广东肇庆526060 南方电网科学研究院广州510663 电网环境保护全国重点实验室(武汉大学) 武汉430072

环保型电工绝缘材料研发是电力行业科技攻关的基础问题和发展趋势,其中电力变压器用环保绝缘油研究是重要方向之一。综述了电力变压器环保绝缘油的研究历程、最新进展和未来发展趋势,首先回顾了矿物油、天然酯及合成酯等三类主要的变压... 详细信息

环保型电工绝缘材料研发是电力行业科技攻关的基础问题和发展趋势,其中电力变压器用环保绝缘油研究是重要方向之一。综述了电力变压器环保绝缘油的研究历程、最新进展和未来发展趋势,首先回顾了矿物油、天然酯及合成酯等三类主要的变压器油研发历史,分析了绝缘油的常规性能指标及其理论评价方法。接着分析了变压器油的绝缘、老化、散热等关键特性的研究现状以及目前绝缘油常见的改性技术。最后分析了量子化学计算应用于绝缘油分子设计研究的现状,提出通过量子化学计算建立绝缘油的宏观性能与微观参数之间的构效关系,从而提升环保绝缘油的研发效率。

关键词：油浸式变压器矿物油天然酯合成酯电工绝缘材料环保型电介质分子设计

Optimal Deployment of Heterogeneous Nodes to Enhance Network Invulnerability

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Computers, Materials & Continua 2022年第11期73卷 3081-3097页

作者： Qian Sun Fengbo Yang Xiaoyi Wang Jiping Xu Huiyan Zhang Li Wang Jiabin Yu Xiao peng ruichao Wang School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China Beijing Laboratory for Intelligent Environmental Protection Beijing100048China Beijing Institute of Fashion Technology Beijing100029China University College Dublin Dublin4Ireland

Wireless sensor networks(WSN)can be used in many fields.In wireless sensor networks,sensor nodes transmit data in multi hop mode.The large number of hops required by data transmission will lead to unbalanced energy consumption and large data transmission delay of the whole network,which greatly affects the invulnerability of the network.Therefore,an optimal deployment of heterogeneous nodes(ODHN)algorithm is proposed to enhance the invulnerability of the wireless sensor networks.The algorithm combines the advantages of DEEC(design of distributed energy efficient clustering)clustering algorithm and BAS(beetle antenna search)optimization algorithm to find the globally optimal deployment locations of heterogeneous nodes.Then,establish a shortcut to communicate with sink nodes through heterogeneous nodes.Besides,considering the practical deployment operation,we set the threshold of the mobile location of heterogeneous nodes,which greatly simplifies the deployment difficulty.Simulation results show that compared with traditional routing protocols,the proposed algorithm can make the network load more evenly,and effectively improve energy-utilization and the fault tolerance of the whole network,which can greatly improve the invulnerability of the wireless sensor networks.

关键词： Wireless sensor networks invulnerability small world characteristic heterogeneous node deployment

Network Invulnerability Enhancement Algorithm Based on WSN Closeness Centrality

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Computers, Materials & Continua 2022年第11期73卷 3021-3038页

作者： Qian Sun Fengbo Yang Xiaoyi Wang Jing Li Jiping Xu Huiyan Zhang Li Wang Jiabin Yu Xiao peng ruichao Wang School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China Beijing Laboratory for Intelligent Environmental Protection Beijing100048China Beijing Institute of Fashion Technology Beijing100029China Smart City College Beijing Union UniversityBeijing100101China University College Dublin Dublin4Ireland

Wireless Sensor Network(WSN)is an important part of the Internet of Things(IoT),which are used for information exchange and communication between smart objects.In practical applications,WSN lifecycle can be influenced by the unbalanced distribution of node centrality and excessive energy consumption,etc.In order to overcome these problems,a heterogeneous wireless sensor network model with small world characteristics is constructed to balance the centrality and enhance the invulnerability of the network.Also,a new WSN centrality measurement method and a new invulnerability measurement model are proposed based on the WSN data transmission characteristics.Simulation results show that the life cycle and data transmission volume of the network can be improved with a lower network construction cost,and the invulnerability of the network is effectively enhanced.

关键词： Wireless sensor networks invulnerability small world characteristics heterogeneous nodes node centrality

Pedestrian and Vehicle Detection Based on Pruning YOLOv4 with Cloud-Edge Collaboration

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Computer Modeling in Engineering & Sciences 2023年第11期137卷 2025-2047页

作者： Huabin Wang ruichao Mo Yuping Chen Weiwei Lin Minxian Xu Bo Liu School of Computer Science and Engineering Huizhou UniversityHuizhou516007China School of Computer Science and Engineering South China University of TechnologyGuangzhou510006China School of Computer Science and Technology South China Normal UniversityGuangzhou510631China Department of New Network Technologies Peng Cheng LaboratoryShenzhen518066China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055China

Nowadays,the rapid development of edge computing has driven an increasing number of deep learning applications deployed at the edge of the network,such as pedestrian and vehicle detection,to provide efficient intelligent services to mobile users.However,as the accuracy requirements continue to increase,the components of deep learning models for pedestrian and vehicle detection,such as YOLOv4,become more sophisticated and the computing resources required for model training are increasing dramatically,which in turn leads to significant challenges in achieving effective deployment on resource-constrained edge devices while ensuring the high accuracy performance.For addressing this challenge,a cloud-edge collaboration-based pedestrian and vehicle detection framework is proposed in this paper,which enables sufficient training of models by utilizing the abundant computing resources in the cloud,and then deploying the well-trained models on edge devices,thus reducing the computing resource requirements for model training on edge devices.Furthermore,to reduce the size of the model deployed on edge devices,an automatic pruning method combines the convolution layer and BN layer is proposed to compress the pedestrian and vehicle detection model size.Experimental results show that the framework proposed in this paper is able to deploy the pruned model on a real edge device,Jetson TX2,with 6.72 times higher FPS.Meanwhile,the channel pruning reduces the volume and the number of parameters to 96.77%for the model,and the computing amount is reduced to 81.37%.

关键词： Pedestrian and vehicle detection YOLOv4 channel pruning cloud-edge collaboration

基于模糊-PID的高空台液压加载系统智能控制

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测控技术 2024年第1期43卷 55-62页

作者：李桂财郭迎清郭鹏飞赵万里彭晋李睿超西北工业大学动力与能源学院陕西西安710129 中国航发四川燃气涡轮研究院四川绵阳621700

为了改善航空发动机高空模拟试车台(简称高空台)液压加载系统的控制性能,解决手动调节控制精度低且闭环控制快速性较差的问题,提出了一种将开环模糊控制与闭环PID控制相结合的智能复合控制方法。首先,结合高空台液压加载试验特点和设备... 详细信息

为了改善航空发动机高空模拟试车台(简称高空台)液压加载系统的控制性能,解决手动调节控制精度低且闭环控制快速性较差的问题,提出了一种将开环模糊控制与闭环PID控制相结合的智能复合控制方法。首先,结合高空台液压加载试验特点和设备特性,利用真实试验数据基于最小二乘系统辨识搭建了系统的分段线性模型。其次,使用频域法设计参数调度的PID控制器,解决了手动调节控制精度低的问题。最后,结合试验操作人员提供的经验知识和历史试验数据结论搭建了模糊开环控制器,设计控制器选择模块和积分补偿模块,将模糊开环控制器与闭环PID控制器相结合形成智能复合控制器。通过仿真验证得出,智能复合控制器的控制效果在精度上明显优于人工手动调节,在快速性上明显优于PID控制器,调节时间缩短了39%~87%。

关键词：航空发动机高空台液压加载系统智能控制模糊控制复合控制

电-Fenton装置的优化与焦化废水的深度处理

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环境工程 2014年第5期32卷 10-13页

作者：彭瑞超于萍罗运柏武汉大学化学与分子科学学院武汉430072

制备了以缚在不锈钢网表面的活性炭纤维作为阴极,钛片为阳极的电Fenton装置,研究了pH、电压、曝气流量和支持电解质Na2SO4的变化对该装置产生H2O2的影响。结果显示:pH为3时,电压为3~9 V,H2O2生成量随着电压的增大而升高;反应时间为140 m... 详细信息

制备了以缚在不锈钢网表面的活性炭纤维作为阴极,钛片为阳极的电Fenton装置,研究了pH、电压、曝气流量和支持电解质Na2SO4的变化对该装置产生H2O2的影响。结果显示:pH为3时,电压为3~9 V,H2O2生成量随着电压的增大而升高;反应时间为140 min,初期H2O2浓度随时间的增加而增加,60 min后,H2O2浓度趋于稳定,最大为26.6 mg/L;体系中溶解氧的存在是产生H2O2的必要条件,H2O2浓度随着曝气流量的增加而增大。采用该装置处理某焦化厂A2O出水,在pH为3,电压为9 V,阴阳极板距离为30 mm,Na2SO4加入量为5 g/L,曝气流量为600 mL/L,Fe2+投加量为0.2 mmol/L的条件下运行2 h,废水COD值明显下降,最大去除率为82.5%。

关键词：活性炭纤维过氧化氢电Fenton 焦化废水

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粉末冶金法制备高性能ODS合金研究进展

粉末冶金工业 2023年第4期33卷 124-131页

作者：周志宏马娇彭金艳康睿超杨胜兵李伟航湖南三一工业职业技术学院湖南长沙410129 武汉理工大学汽车学院湖北武汉430070 合肥工业大学材料科学与工程学院安徽合肥230009

氧化物弥散强化合金是核反应堆材料中最具有应用前景的材料之一。得益于在金属基体中引入了大量分布均匀的纳米氧化物,该合金具有良好的高温力学性能。同时,在ODS Fe基合金中加入一定比例的Cr和Al,会使合金的耐蚀性能大幅度提升。由于... 详细信息

氧化物弥散强化合金是核反应堆材料中最具有应用前景的材料之一。得益于在金属基体中引入了大量分布均匀的纳米氧化物,该合金具有良好的高温力学性能。同时,在ODS Fe基合金中加入一定比例的Cr和Al,会使合金的耐蚀性能大幅度提升。由于采用粉末冶金法制备的ODS合金的综合性能优于熔炼法,因此近年来主要用粉末冶金法制备ODS合金。系统的总结了最近国内外多种合金粉体的制备和烧结工艺,其中包括采用机械合金化、内氧化法以及水热-冷冻干燥法制备合金粉体;采用热等静压、粉末锻造以及放电等离子烧结制备合金块体,同时对各种制备工艺目前的研究现状和存在的问题进行了阐述,旨在为制备综合性能优良的先进ODS合金提供参考。

关键词：氧化物弥散强化合金核反应堆纳米氧化物粉末冶金机械合金化

3D打印金属假体重建下肢骨干恶性骨肿瘤切除术后骨缺损

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中华骨科杂志 2023年第13期43卷 878-884页

作者：张鹏田文张瑞超牛晓颖屈国新杜鑫辉王鑫王家强姚伟涛郑州大学附属肿瘤医院(河南省肿瘤医院)骨与软组织科郑州450008 郑州大学基础医学院郑州450001

目的探讨3D打印金属假体重建下肢骨干恶性骨肿瘤切除术后骨缺损的早期疗效。方法回顾性分析2019年3月至2022年3月郑州大学附属肿瘤医院采用3D打印个体化金属假体置换重建34例下肢骨干恶性骨肿瘤切除术后骨缺损的患者资料,男23例、女11例... 详细信息

目的探讨3D打印金属假体重建下肢骨干恶性骨肿瘤切除术后骨缺损的早期疗效。方法回顾性分析2019年3月至2022年3月郑州大学附属肿瘤医院采用3D打印个体化金属假体置换重建34例下肢骨干恶性骨肿瘤切除术后骨缺损的患者资料,男23例、女11例,年龄(19.1±15.2)岁(范围7~80岁),其中22例患者年龄<18岁。病变位于股骨近端3例、股骨中远端15例、胫骨近端10例、胫骨远端6例;骨肉瘤24例、Ewing肉瘤6例、未分化肉瘤2例、骨纤维肉瘤1例、恶性骨巨细胞瘤1例。随访并记录切口愈合情况、有无假体周围断裂及无菌性松动、假体-骨界面愈合情况、双下肢是否不等长、术后并发症等。采用实体瘤疗效评价标准(response evaluation criteria in solid tumor,RECIST)评价肿瘤转归,采用美国肌肉骨骼肿瘤协会(Musculoskeletal Tumor Society,MSTS)93功能评分评价下肢功能。结果所有患者手术均顺利完成,34例患者病变长度(125.5±35.4)mm(范围70~240 mm)、截骨长度(160.2±33.9)mm(范围80~275 mm)。肿瘤均未累及术前设计的截骨面。定制假体均安装牢固,与保留关节面一侧匹配紧密。术后2例出现局部切口脂肪液化、4例出现切口浅表感染,经清创及抗生素治疗后愈合。1例胫骨远端骨肉瘤患者假体-骨界面愈合较差,术后2个月出现严重假体周围感染致假体植入失败,经去除假体、控制感染及使用Ilizarov技术牵拉成骨治疗后感染控制,局部成骨可;其余33例患者假体-骨界面愈合良好。术后7个月,1例患者假体接触面局部骨质有局限吸收,但金属假体及螺钉未松动;其余患者均未发生感染及假体松动、断裂等并发症。术后所有患者均存活且获得随访,随访时间(13.8±5.6)个月(范围7~27个月),无一例发生截骨端肿瘤复发,但5例发生肺转移。16例患者出现双下肢不等长,其中10例长度差<2 cm、3例为2~5 cm、3例超过5 cm。除1例因感染而取出假体外,其余33例患者术后MSTS 93评分为(24.9±2.2)分(范围19~28分),评价为优26例、良7例。根据RECIST标准,34例患者中26例完全缓解、5例疾病进展、3例疾病稳定。结论3D打印金属假体重建是治疗下肢恶性骨肿瘤切除术后骨缺损的有效方式之一,该方法安全可靠,早期疗效满意。

关键词： 3D打印骨重建骨肿瘤下肢骨干假体和植入物