期刊文献+
共找到7,822篇文章
< 1 2 250 >
每页显示 20 50 100
An Improved Solov2 Based on Attention Mechanism and Weighted Loss Function for Electrical Equipment Instance Segmentation
1
作者 Junpeng Wu Zhenpeng Liu +2 位作者 Xingfan Jiang Xinguang Tao Ye Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第1期677-694,共18页
The current existing problem of deep learning framework for the detection and segmentation of electrical equipment is dominantly related to low precision.Because of the reliable,safe and easy-to-operate technology pro... The current existing problem of deep learning framework for the detection and segmentation of electrical equipment is dominantly related to low precision.Because of the reliable,safe and easy-to-operate technology provided by deep learning-based video surveillance for unmanned inspection of electrical equipment,this paper uses the bottleneck attention module(BAM)attention mechanism to improve the Solov2 model and proposes a new electrical equipment segmentation mode.Firstly,the BAM attention mechanism is integrated into the feature extraction network to adaptively learn the correlation between feature channels,thereby improving the expression ability of the feature map;secondly,the weighted sum of CrossEntropy Loss and Dice loss is designed as the mask loss to improve the segmentation accuracy and robustness of the model;finally,the non-maximal suppression(NMS)algorithm to better handle the overlap problem in instance segmentation.Experimental results show that the proposed method achieves an average segmentation accuracy of mAP of 80.4% on three types of electrical equipment datasets,including transformers,insulators and voltage transformers,which improve the detection accuracy by more than 5.7% compared with the original Solov2 model.The segmentation model proposed can provide a focusing technical means for the intelligent management of power systems. 展开更多
关键词 Deep learning electrical equipment attention mechanism weighted loss function
下载PDF
Operation and Management of Electrical Equipment in Iron and Steel Enterprises
2
作者 Wen Liao Kenan Yang 《Frontiers of Metallurgical Industry》 2024年第1期5-8,共4页
How to ensure the reliable operation of the complex and huge electrical system composed of a large number of electrical equipment in iron and steel enterprises?Combined with working experience,the author introduces fo... How to ensure the reliable operation of the complex and huge electrical system composed of a large number of electrical equipment in iron and steel enterprises?Combined with working experience,the author introduces four main factors affecting the normal operation of equipment,analyzes five main problems existing in the operation and management of electrical equipment,and puts forward corresponding improvement measures,so as to improve the management level of electrical equipment in iron and steel enterprises. 展开更多
关键词 iron and steel enterprises electrical equipment operation management
下载PDF
Real-time localization for underwater equipment using an extremely low frequency electric field 被引量:1
3
作者 Jia-wei Zhang Peng Yu +1 位作者 Run-xiang Jiang Tao-tao Xie 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第8期203-212,共10页
A new real-time underwater equipment location method adopting an electric field induced by a standard current source is proposed.Our goals were real-time tracking and location of stationary or moving underwater equipm... A new real-time underwater equipment location method adopting an electric field induced by a standard current source is proposed.Our goals were real-time tracking and location of stationary or moving underwater equipment both in shallow and deep seas,under noisy conditions.The main features of this method are as follows:(1)a standard current source on the water surface,which can be towed by a vehicle,consisting of two electrodes,a signal generator,and a GPS unit;(2)measurement of the extremely low frequency(ELF)electric field emitted by the current source,made possible by electric field sensors on the underwater equipment;(3)position of the underwater equipment is estimated in real time based on a progressive update extended Kalman filter(PUEKF),which is carried out using the propagation model of an ELF electric field because the electric field at the position of the underwater equipment and the current source position are known.We verified the accuracy of our method and confirmed real-time location feasibility through numerical,physical scale,and real-time sea experiments.Through numerical experiments,we verified that our method works for underwater equipment location in real-world conditions,and the location error can be less than 0.2 m.Next,real-time location experiments for stationary underwater measuring equipment in water tank were conducted.The result shows that the location error can be less than 0.1 m.We also confirmed real-time location feasibility through the use of offshore experiment.We expect that our method will complement conventional underwater acoustic location methods for underwater equipment in acoustically noisy environments. 展开更多
关键词 Termsd Real-time tracking and location method Underwater equipment location ELF electric field Shallow sea Physical scale experiment Sea experiment
下载PDF
Experimental and analytical studies on multiple tuned mass dampers for seismic protection of porcelain electrical equipment 被引量:9
4
作者 Bai Wen Dai Junwu +2 位作者 Zhou Huimeng Yang Yongqiang Ning Xiaoqing 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第4期803-813,共11页
Porcelain electrical equipment (PEE), such as current transformers, is critical to power supply systems, but its seismic performance during past earthquakes has not been satisfactory. This paper studies the seismic ... Porcelain electrical equipment (PEE), such as current transformers, is critical to power supply systems, but its seismic performance during past earthquakes has not been satisfactory. This paper studies the seismic performance of two typical types of PEE and proposes a damping method for PEE based on multiple tuned mass dampers (MTMD). An MTMD damping device involving three mass units, named a triple tuned mass damper (TTMD), is designed and manufactured. Through shake table tests and finite element analysis, the dynamic characteristics of the PEE are studied and the effectiveness of the MTMD damping method is verified. The adverse influence of MTMD redundant mass to damping efficiency is studied and relevant equations are derived. MTMD robustness is verified through adjusting TTMD control frequencies. The damping effectiveness of TTMD, when the peak ground acceleration far exceeds the design value, is studied. Both shake table tests and finite element analysis indicate that MTMD is effective and robust in attenuating PEE seismic responses. TTMD remains effective when the PGA far exceeds the design value and when control deviations are considered. 展开更多
关键词 current transformer DAMPING porcelain electrical equipment finite element analysis multiple tuned massdampers shake table test
下载PDF
A REPLACEMENT MODEL FOR QUEUEING SYSTEM WITH REPAIRABLE ELECTRICAL EQUIPMENT OF AUTOMATIC STEEL ROLLING 被引量:1
5
作者 钟福金 张元林 贾积身 《Journal of Southeast University(English Edition)》 EI CAS 1995年第1期114-118,共5页
The optimal replacement model for the repairable queueing system con-sisting of single electrical equipment of automatic steel rolling is studied. Assumingthat the equipment after repair is not “as goed as new” , by... The optimal replacement model for the repairable queueing system con-sisting of single electrical equipment of automatic steel rolling is studied. Assumingthat the equipment after repair is not “as goed as new” , by using geometric pro-cess, we take the n 展开更多
关键词 RENEWAL process RENEWAL REWARD theorem convolution / geometricprocess REPAIRABLE electricAL equipment
下载PDF
An Improved Biometric Fuzzy Signature with Timestamp of Blockchain Technology for Electrical Equipment Maintenance
6
作者 Rao Fu Liming Wang +3 位作者 Xuesong Huo Pei Pei Haitao Jiang Zhongxing Fu 《Energy Engineering》 EI 2022年第6期2621-2636,共16页
The power infrastructure of the power system is massive in size and dispersed throughout the system.Therefore,how to protect the information security in the operation and maintenance of power equipment is a difficult ... The power infrastructure of the power system is massive in size and dispersed throughout the system.Therefore,how to protect the information security in the operation and maintenance of power equipment is a difficult problem.This paper proposes an improved time-stamped blockchain technology biometric fuzzy feature for electrical equipment maintenance.Compared with previous blockchain transactions,the time-stamped fuzzy biometric signature proposed in this paper overcomes the difficulty that the key is easy to be stolen by hackers and can protect the security of information during operation and maintenance.Finally,the effectiveness of the proposed method is verified by experiments. 展开更多
关键词 Blockchain technology fault diagnosis of electrical equipment biometric fuzzy signature TIMESTAMP deep learning technology
下载PDF
Zibo Sangde Machinery Equipment Co., Ltd The Most Professional Manufacturer of Refractory Electric Screw Press in China
7
《China's Refractories》 CAS 2012年第3期I0001-I0001,共1页
Zibo Sangde Machinery Equipment Co., Ltd. is the first Manufacturer of Refractory Electric Screw Press in China, in the year of 2008, our company produced the first set 315T Refractory Electric Program-controlled Scre... Zibo Sangde Machinery Equipment Co., Ltd. is the first Manufacturer of Refractory Electric Screw Press in China, in the year of 2008, our company produced the first set 315T Refractory Electric Program-controlled Screw Press in China, which is no friction discs, simple structure, with PLC controlling the brick forming process, no need special operator. Once upon the Press was on the market, it achieved a strong interests and reputations from many Refractory Factories because of its Highefficient, Energy-saving(can save by 40-50% electricity comparing to the Friction Press), manpower reduction and improving the quality of bricks. 展开更多
关键词 Zibo Sangde Machinery equipment Co LTD The Most Professional Manufacturer of Refractory electric Screw Press in China
下载PDF
New “Intellectual Networks” (Smart Grid) for Detecting Electrical Equipment Faults, Defects and Weaknesses
8
作者 Alexander Yu. Khrennikov 《Smart Grid and Renewable Energy》 2012年第3期159-164,共6页
The most important elements of “intellectual networks” (Smart Grid) are the systems of monitoring the parameters of electrical equipment. Information-measuring systems (IMS), which described in this paper, were prop... The most important elements of “intellectual networks” (Smart Grid) are the systems of monitoring the parameters of electrical equipment. Information-measuring systems (IMS), which described in this paper, were proposed to use together with rapid digital protection against short-circuit regimes in transformer windings. This paper presents an application’s experience of LVI-testing, some results of the use of Frequency Response Analysis (FRA) to check the condition of transformer windings and infra-red control results of electrical equipment. The LVI method and short-circuit inductive reactance measurements are sensitive for detecting such faults as radial, axial winding deformations, a twisting of low-voltage or regulating winding, a losing of winding’s pressing and others. 展开更多
关键词 INTELLECTUAL NETWORKS Smart Grid Monitoring SYSTEM electrical equipment Information-Measuring SYSTEM Frequency Response Analysis Transformer WINDING Fault Diagnostic Low Voltage Impulse Method SHORT-CIRCUIT Inductive REACTANCE Measurement
下载PDF
Hardware,Machines & Electrical Equipment From Wenzhou
9
《China's Foreign Trade》 1994年第10期18-18,共1页
Scissors and locks are famous products from Wenzhou. Now scissors from the city including multi-purpose, tailoring, tourist and special-purpose ones and exquisite fruit and artistic knives have entered the world marke... Scissors and locks are famous products from Wenzhou. Now scissors from the city including multi-purpose, tailoring, tourist and special-purpose ones and exquisite fruit and artistic knives have entered the world market. At the 展开更多
关键词 Hardware Machines electrical equipment From Wenzhou
下载PDF
Japanese National Safety Standards for Electrical Equipment
10
作者 Junkichi Sumiya 《China Standardization》 2006年第4期17-22,共6页
I am working in Japan electrical safety &amp; environment technology laboratory,which is called JET for short. In JET, we are carrying out the safety test of electrical equipmentaccording to Japanese domestic stan... I am working in Japan electrical safety &amp; environment technology laboratory,which is called JET for short. In JET, we are carrying out the safety test of electrical equipmentaccording to Japanese domestic standards or IEC standards. And in my section, our stuff is draftingsome national safety standards harmonized with IEC in cooperation with the government. The standardsare applied for the mandatory regulation and other schemes. 展开更多
关键词 IEC JET Japanese National Safety Standards for electrical equipment CISPR JIS PSE
下载PDF
A Comparison of Domestic and Foreign Seismic Fortification Standards for Electrical Equipment
11
作者 You Hongbing Zhao Fengxin 《Earthquake Research in China》 2013年第4期553-566,共14页
It is of great significance to make comparative analyses of seismic fortification criteria at home and abroad for improving the anti-seismic capability of electrical equipment and revising the relevant national standa... It is of great significance to make comparative analyses of seismic fortification criteria at home and abroad for improving the anti-seismic capability of electrical equipment and revising the relevant national standards.A brief overview of American,Japanese,IEC standards and Chinese seismic design codes for electrical equipment is presented.Differences between these seismic fortification standards of electrical equipment are compared and analyzed in respect of the goal and level of seismic fortification and the seismic design spectrum.The advantages and disadvantages of Chinese standards are pointed out.Through learning from foreign experience on the determination of seismic fortification standards,recommendations are made for the improvement and revision of Chinese seismic fortification standards for electrical equipment. 展开更多
关键词 electrical equipment Seismic fortification standard Comparative analysis Recommendations for improvement
下载PDF
Analysis on Economic Performance of Electrical Equipment Industry in 2010
12
作者 China Electrical Equipment Industrial Association Zhu Li 《Electricity》 2011年第2期11-13,共3页
In this paper the analysis is presented on the economic performance of the electrical equipment industry in 2010.Substantial increase was seen in both the economic aggregate indices such as production and sales,and ec... In this paper the analysis is presented on the economic performance of the electrical equipment industry in 2010.Substantial increase was seen in both the economic aggregate indices such as production and sales,and economic efficiency indices such as profits.Increase of indices that reflect foreign trade situation of the industry,such as import volume,export volume,gross import and export volume,and export delivery volume were prominent in particular.The industry has completely stepped out of the "negative growth" predicament in 2009,comprehensively outperformed the level in 2008,and recovered true growth.The economic situation of the electrical equipment industry in 2011 is also predicted in this paper. 展开更多
关键词 electrical equipment industry economic operation
下载PDF
Simulation of seafloor electrical resistivity measuring equipment based on 3D finite element method
13
作者 NAN Zeyu FAN Xiaomin ZHANG Yi XU Jun 《Global Geology》 2012年第2期172-175,共4页
In order to explore the mineral resources buried in sea mud,it is necessary to use seabed resistivity measuring equipment,which works closer to the sediments than ordinary ship-based geophysical measuring equipment. B... In order to explore the mineral resources buried in sea mud,it is necessary to use seabed resistivity measuring equipment,which works closer to the sediments than ordinary ship-based geophysical measuring equipment. Because of the harsh environment of seafloor,high pressure and highly conductive seawater,marine magnetotelluric method developed slowly. The sea floor environment is similar to the environment of logging, According to the design of dual lateral logging equipment,a new equipment for seafloor electrical resistivity measurement is designed. Four 3D FEM models that contain resistivity abnormal targets are built to test the ability of this equipment to locate different shape of shallow buried resistivity abnormal targets in sea mud. The authors propose the method to correct the response curve while the bottom surface of this equipment is suspended or not parallel to the seafloor. The resistivity of targets can be calculated accurately. 展开更多
关键词 3D FEM method dual later log gas hydrate polymetallic nodules seafloor electrical resistivity measurement equipment
下载PDF
Shanghai Electric (Group) Corp.- The pioneer of Power Equipment Manufacturing in China
14
作者 Zhou FeidaPresident, Shanghai Electric (Group) Corp. 《Electricity》 1996年第1期2-4,共3页
Shanghai Electric (Group) Corporation (SEC) is a large-scale industrial enterprise group in China engaged in design and manufacturing of power generation equipment, power transmission and distribution equipment and he... Shanghai Electric (Group) Corporation (SEC) is a large-scale industrial enterprise group in China engaged in design and manufacturing of power generation equipment, power transmission and distribution equipment and heavy machinery equipment. SEC is separately catalogued in the program of the State Planning Commission. Based on its main economic norms, SEC is listed as one of the 500 展开更多
关键词 Corp Shanghai electric The pioneer of Power equipment Manufacturing in China
下载PDF
Characteristic Period Value of the Seismic Design Response Spectrum of UHV Electrical Equipment
15
作者 You Hongbing Zhao Fengxin You He 《Earthquake Research in China》 CSCD 2015年第1期117-127,共11页
Characteristic period is an important parameter of the seismic design response spectrum. There is important theoretical significance and engineering application value to the study of the characteristic period of seism... Characteristic period is an important parameter of the seismic design response spectrum. There is important theoretical significance and engineering application value to the study of the characteristic period of seismic design response spectrum of ultra high voltage (UHV) electrical equipment. In this paper, 1448 horizontal earthquake records within the world scope including the United States and Japan for Site Class m were analyzed. Results show that both magnitude and epicentral distance have great influence on the characteristic period. About 80 % of characteristic periods of strong earthquake records are about 0. 9s. Statistical analysis was conducted on the seismic hazard assessment results of 312 projects of China in recent years, and it is found that about 70 % of characteristic periods are about 0. 9s. Combined with the related code comparison and analysis, it is suggested that the characteristic period of the seismic design response spectrmn of UHV electrical equipment should select 0. 9s in order to effectively guarantee the seismic safety of UHV electrical equipment. 展开更多
关键词 UHV electrical equipment Seismic design response spectrum Characteristicperiod Statistical analysis
下载PDF
Study on Negative Impact of Harmonic Components on Sensitive Electric Equipment
16
作者 Miroslav Dubovsky Alena Otcenasova Michal Pokorny 《Journal of Energy and Power Engineering》 2013年第4期733-739,共7页
Distribution systems operators are often confronted with declined power quality, which can cause substantial economical losses. The problem analyzed in paper concerns thyristor controlled direct current motor used for... Distribution systems operators are often confronted with declined power quality, which can cause substantial economical losses. The problem analyzed in paper concerns thyristor controlled direct current motor used for ski-lift in ski resort as a source of disturbances with negative impact on sensitive electric equipment, which is then unable to operate correctly. To solve mentioned problems, series of measurements of voltage quality parameters were carried out according to the respective valid standards. Crucial power quality parameters necessary for parallel power active filter design were then analyzed. Power active filter compensates power factor and filters characteristic current harmonics. After power active filter was put into operation, power quality problems were eliminated. Payback period is estimated up to four years. 展开更多
关键词 Power quality higher harmonics total harmonic distortion power factor power active filter sensitive electric equipment.
下载PDF
NINGBO TENDERING CENTER OF MACHINERY AND ELECTRIC EQUIPMENT
17
《中国招标》 1995年第4期24-24,共1页
Ningbo TenderingCenter of Machinery andElectric Equipment wasestablished with the ap-proval by the CompetantState Department andNingbo Municipal Gov-ernment.It is a legal en-tity subordinated to Ning-bo Municipal Econ... Ningbo TenderingCenter of Machinery andElectric Equipment wasestablished with the ap-proval by the CompetantState Department andNingbo Municipal Gov-ernment.It is a legal en-tity subordinated to Ning-bo Municipal EconomicCommittee,specializingin tendering service un-der the supervision,in-spection and guidance ofthe China National Ten-dering Center of Machin-ery and Electric Equip-ment. 展开更多
关键词 der PRO NINGBO TENDERING CENTER OF MACHINERY AND electric equipment
下载PDF
EPLAN Electric P8在物料分类装置电气设计中的应用
18
作者 张虎 《企业技术开发》 2015年第9期21-22,共2页
文章介绍一套物料分类装置电气部分的设计过程,使用EPLAN Electric P8来辅助设计、绘制电气电路图。通过与Auto CAD的对比,说明了EPLAN Electric P8在电气绘图方面的优势,重点介绍了如何应用EPLAN Electric P8进行物料分类装置电气部分... 文章介绍一套物料分类装置电气部分的设计过程,使用EPLAN Electric P8来辅助设计、绘制电气电路图。通过与Auto CAD的对比,说明了EPLAN Electric P8在电气绘图方面的优势,重点介绍了如何应用EPLAN Electric P8进行物料分类装置电气部分的设计。 展开更多
关键词 EPLAN electric P8 物料分类装置 绘制电路图
下载PDF
基于双对数正态分布的电瓷型电气设备地震易损性研究 被引量:3
19
作者 李吉超 尚庆学 +1 位作者 罗清宇 王涛 《工程力学》 EI CSCD 北大核心 2024年第2期125-136,共12页
总结了110 kV和220 kV典型电气设备的地震易损性曲线研究成果,考虑不同研究成果的离散性,基于双对数正态分布给出了抗震能力中值、随机性和不确定性建议值。进一步开展220 kV变电站系统的抗震性能分析,定量评价了变电站的功能性。研究... 总结了110 kV和220 kV典型电气设备的地震易损性曲线研究成果,考虑不同研究成果的离散性,基于双对数正态分布给出了抗震能力中值、随机性和不确定性建议值。进一步开展220 kV变电站系统的抗震性能分析,定量评价了变电站的功能性。研究结果表明:双对数正态分布可以较好地反映电气设备地震易损性的离散性,尤其是模型、方法等原因导致的不确定性。变电站系统的抗震能力低于电气设备的抗震能力,设计中应采取措施提高变电站的冗余性。变电站系统抗震性能与电气设备抗震能力中值正相关,与随机性和不确定性呈负相关。 展开更多
关键词 电气设备 地震易损性 双对数正态分布 变电站系统 系统功能
下载PDF
基于轻量化YOLOv5的电气设备外部缺陷检测 被引量:1
20
作者 廖晓辉 谢子晨 +2 位作者 辛忠良 陈怡 叶梁劲 《郑州大学学报(工学版)》 CAS 北大核心 2024年第4期117-124,共8页
为了提高变电站电气设备外部缺陷实时检测的精度,同时让检测模型更加轻量化,提出了一种基于轻量化YOLOv5的电气设备外部缺陷检测方法。首先,构建电气设备外部缺陷图像数据集并进行数据增强处理。其次,采用3种优化策略对原YOLOv5进行改进... 为了提高变电站电气设备外部缺陷实时检测的精度,同时让检测模型更加轻量化,提出了一种基于轻量化YOLOv5的电气设备外部缺陷检测方法。首先,构建电气设备外部缺陷图像数据集并进行数据增强处理。其次,采用3种优化策略对原YOLOv5进行改进:通过引入EfficientViT网络改进算法主干网络,减少模型参数量,并在算法Neck部分中加入SimAM无参数注意力机制来提高变电站复杂背景下的识别精度,同时采用Soft-NMS模块来改进检测框筛选方式,避免出现缺陷漏检现象。最后,通过消融实验进行验证。结果表明:轻量化后的电气设备外部缺陷检测模型mAP值稳定在86.4%,与原模型相比提高了1.2百分点,模型参数量减少了20%,计算量减少了38%,模型大小为11 MB,比原模型减少了19.7%。改进后的模型能够满足设备外部缺陷实时检测的要求,可以实现模型的轻量化部署。 展开更多
关键词 缺陷检测 电气设备 轻量化YOLOv5 EfficientViT网络 SimAM注意力 Soft-NMS结构
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部