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Extreme Pressure Equipments 被引量:4
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作者 ZHENG Jinyang WU Linlin SHI Jianfeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第2期202-206,共5页
Pressure equipments in the process industries and the newly developing industries usually have extreme sizes and/or are subjected to extreme operating conditions such as high pressure,blast loading,cryogenic temperatu... Pressure equipments in the process industries and the newly developing industries usually have extreme sizes and/or are subjected to extreme operating conditions such as high pressure,blast loading,cryogenic temperature,elevated temperature,complex corrosion,and so on.In order to understand,research and develop these equipments systematically,a concept of extreme pressure equipments(EPEs) is proposed.The applications and demands of EPEs in petrochemical industry,coal chemical industry,advanced energy,military,space technology,and environment protection are introduced.Basic scientific problems in material,design,inspection, and safety related to EPEs are discussed.Then,take chemical composition,manufacturing process,service duration,and operating conditions for example,main factors which affect material properties of EPEs are analyzed.New design concepts including design based on life cycle,dynamic design and light-weight design are introduced.EPEs with higher efficiency,lower cost and safer performance are in urgent demand in national major projects including ten million ton oil refinery,one million ton ethylene,liquefied natural gas transportation,and nuclear power plant.Thus,further research should be conducted on information acquisition, multi-mechanism damage coupling model,damage inspection,life prediction,online safety monitoring,maintenance strategy,safety pre-warning system,and emergency system. 展开更多
关键词 pressure equipment pressure vessel pressure pipe
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Trend Prediction Method Based on the Largest Lyapunov Exponent for Large Rotating Machine Equipments 被引量:5
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作者 徐小力 朱春梅 张建民 《Journal of Beijing Institute of Technology》 EI CAS 2009年第4期433-436,共4页
In order to predict electromechanical equipments' nonlinear and non-stationary condition effectively, max Lyapunov exponent is introduced to the fault trend prediction of large rotating mechanical equipments based on... In order to predict electromechanical equipments' nonlinear and non-stationary condition effectively, max Lyapunov exponent is introduced to the fault trend prediction of large rotating mechanical equipments based on chaos theory. The predict method of chaos time series and two methods of proposing f and F are dis- cussed. The arithmetic of max prediction time of chaos time series is provided. Aiming at the key part of large rotating mechanical equipments-bearing, used this prediction method the simulation experiment is carried out. The result shows that this method has excellent performance for condition trend prediction. 展开更多
关键词 largest Lyapunov exponent large rotating machine equipments developing condition prediction
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INTRODUCTION TO NEW TECHNOLOGY AND EQUIPMENTS IN PINGGUO ALUMINA REFINERY 被引量:1
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作者 S.J.Yang G.Y.Gan L.Z.Wang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1998年第5期360-364,共5页
The new technology and equipments used in alumina refinery in PINGGUO ALUMINUM COMPANY were introduced. Problems encountered during early period of its operation and improvements to the process and equipments were dis... The new technology and equipments used in alumina refinery in PINGGUO ALUMINUM COMPANY were introduced. Problems encountered during early period of its operation and improvements to the process and equipments were discussed. Current opemtion situation and pedect technical and economical figures were also introduced. 展开更多
关键词 ALUMINA equipMENT TECHNOLOGY IMPROVEMENT
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Key Technologies and Development Trends in Advanced Intelligent Sawing Equipments 被引量:3
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作者 Yangyu Wang Yongle Zhang +1 位作者 Dapeng Tan Yongchao Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第3期175-194,共20页
As a starting point in equipment manufacturing,sawing plays an important role in industrial production.Intelligent manufacturing equipment is an important carrier of intelligent manufacturing technologies.Due to the b... As a starting point in equipment manufacturing,sawing plays an important role in industrial production.Intelligent manufacturing equipment is an important carrier of intelligent manufacturing technologies.Due to the backwardness of intelligent technology,the comprehensive performance of sawing equipments in China is obviously different from that in foreign countries.State of the art of advanced sawing equipments is investigated along with the technical bottleneck of sawing machine tool manufacturing,and a new industrial scheme of replacing turning-milling by sawing is described.The key technologies of processing-measuring integrated control,multi-body dynamic optimization,the collaborative sawing network framework,the distributed cloud sawing platform,and the self-adapting service method are analyzed;with consideration of the problems of poor processing control stableness,low single machine intelligence level,no on-line processing data service and active flutter suppression of sawing with wide-width and heavy-load working conditions.Suggested directions for further research,industry implementation,and industry-research collaboration are provided. 展开更多
关键词 Sawing equipments Processing-measuring integrated control Collaborative sawing framework Intelligent network middleware Sawing cloud service platform
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Research and design of the main equipments and structure of Xiangjiaba shiplift 被引量:3
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作者 Liao Lekang Zhu Hong Zhang Rui 《Engineering Sciences》 EI 2014年第5期81-89,共9页
The type of pinion and rack vertical shiplifts has been developed in recent a couple of years in the construction of dams.But the design methods and methodologies have rarely been discussed in literature.The Xiangjiab... The type of pinion and rack vertical shiplifts has been developed in recent a couple of years in the construction of dams.But the design methods and methodologies have rarely been discussed in literature.The Xiangjiaba shiplift is the second shiplift of this type following the Three Gorges shiplift.Being aimed at the technological rationality of the design in synthetically considering security,economy and applicability,this paper presents the research results of some vital issues relating the design of the Xiangjiaba shiplift,including the determination of design water depth of ship chamber based on fluid numeral computation and physical model test,the optimum design of general layout of main equipments and the civil structure of the Xiangjiaba shiplift,the finite element method(FEM) analysis of stress,vibration modes and the buckling of ship chamber,antiseismic research and the design of structures and mechanisms of the shiplift and the optimum design of driving mechanisms.This research provides the theoretical basis for the design of the Xiangjiaba shiplift.The design principles and research methods are valuable for the design of the same type of shiplifts. 展开更多
关键词 Xiangjiaba shiplift equipments and structure fluid numeral computation FEM computation optimum design seismic design layout
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Numerical research on dynamic response of naval equipments subjected to impact loads
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作者 陈海龙 周维星 +1 位作者 朱枫 周其新 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第4期504-510,共7页
When subjected to underwater explosion,the anti-shock performance of naval equipment is a key factor affecting the fighting capacity and safety of a war ship. For large-scale naval equipment,it is costly to do the sho... When subjected to underwater explosion,the anti-shock performance of naval equipment is a key factor affecting the fighting capacity and safety of a war ship. For large-scale naval equipment,it is costly to do the shock test for its huge mass and large size. Consequently,the numerical research was carried our to study the shock resistance of the equipment. Taking turbo-charger set for example,its anti-shock performance was studied using software ABAQUS based on the time-domain shock analysis method presented in BV043 /85. According to the analysis results,shock response of typical regions is obtained,some regularity curves are concluded by analyzing the Mises stress of the typical regions,and the weak regions are found out. The study can provide some references on design of turbo-charger set. 展开更多
关键词 naval equipment ANTI-SHOCK UNDERWATER explorsion NUMERICAL simulation turbo-charger SET
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Entanglement distribution using three-mode separable state with imperfect equipments
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作者 宋婷婷 张劼 +1 位作者 高飞 温巧燕 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第7期74-80,共7页
We show a scheme to distribute the entanglement by using three-mode separable Gaussian state prepared with imperfect equipments. The scheme achieves the aim that the entanglement is distributed between two distant par... We show a scheme to distribute the entanglement by using three-mode separable Gaussian state prepared with imperfect equipments. The scheme achieves the aim that the entanglement is distributed between two distant parties with only Gaussian operations and linear optics elements. Moreover, we analyse the logarithmic negativity of the entanglement shared between the two parties when the systems are imperfect and arrive at the conclusion that the logarithmic negativity is asymptotically stable with fluctuations within a certain space range. 展开更多
关键词 entanglement distribution separable state imperfect equipments
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A Space State Forecast Model for Dam Construction Equipments Based on Analysis Prediction Theory
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作者 WU Qingming CHEN Yongqiang ZHANG Zhiqiang 《Wuhan University Journal of Natural Sciences》 CAS 2007年第2期307-310,共4页
Anti-collision equipments system is developed to solve the collision problems of dam construction equipments, and in the system the determination of equipments' space state is important. A uniform moving equation of ... Anti-collision equipments system is developed to solve the collision problems of dam construction equipments, and in the system the determination of equipments' space state is important. A uniform moving equation of equipments is established based on the analysis prediction theory and the movements states of equipments. Method of least square was employed to deal with discrete data of equipments' space position. Fitting equation matched with the movement equation was presented to do data fitting, and a relevant algorithm was given. Applying the fitting equation, current and future space state of equipments can be accurately predicted. Finally, a case is given and results show that numerical values of data were steady and their precision was high. In LongTan dam construction of the equipments antiollision system, applying this method to forecast the equipments' space states and practical running of the system indicate that this method can improve the precision of position, obtain the better forecasting effect and increase the robustness of the system. 展开更多
关键词 construction equipments analysis prediction anticollision system method of least square
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Applying Neural Network withGenetic Algorithm and FuzzySelection Models to Select Equipmentsfor Fully-Mechanized Coal Mining
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作者 王新宇 吴瑞明 冯春花 《Journal of China University of Mining and Technology》 2004年第2期147-151,共5页
According to the typical engineering samples, a neural net work model with genetic algorithm to optimize weight values is put forward to forecast the productivities and efficiencies of mining faces. By this model we c... According to the typical engineering samples, a neural net work model with genetic algorithm to optimize weight values is put forward to forecast the productivities and efficiencies of mining faces. By this model we can obtain the possible achievements of available equipment combinations under certain geological situations of fully-mechanized coal mining faces. Then theory of fuzzy selection is applied to evaluate the performance of each equipment combination. By detailed empirical analysis, this model integrates the functions of forecasting mining faces' achievements and selecting optimal equipment combination and is helpful to the decision of equipment combination for fully-mechanized coal mining. 展开更多
关键词 GENETIC algorithm artificial NEURAL network FUZZY SELECTION SELECTION of equipment combination
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Research and Analysis on Cooling Capacity of Temperature Adjustment Equipments in Agricultural Multi-span Greenhouse
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作者 Dong WANG Xiaohu YANG 《Asian Agricultural Research》 2017年第11期44-47,53,共5页
The high summer indoor temperature in agricultural greenhouse is not conducive to crop growth,so it is necessary to cool the greenhouse. In this study,taking the agricultural multi-span greenhouse with strong temperat... The high summer indoor temperature in agricultural greenhouse is not conducive to crop growth,so it is necessary to cool the greenhouse. In this study,taking the agricultural multi-span greenhouse with strong temperature adjustment ability for example,we make an experimental analysis on the temperature changes inside and outside the greenhouse under nine different equipment combinations( fan,skylight,sunshade,sunshade + fan,cooling pad + fan,skylight + fan,sunshade + skylight,sunshade + fan + cooling pad,sunshade + skylight + fan),respectively,and conduct the overall assessment on the measures to cool the summer agricultural greenhouse,in order to provide a reference for selecting a cost-effective cooling method for greenhouse. Tests show that the three treatment modes of fan,sunshade and sunshade + fan almost have no cooling capacity; skylight,sunshade + skylight have cooling capacity,but the effect is slow; cooling pad + fan,sunshade + skylight +fan can reduce the indoor temperature,but the effect is not very good; skylight and fan have good cooling effect; sunshade + fan + cooling pad has obvious cooling effect,which can well meet the cooling needs in the summer greenhouse. 展开更多
关键词 Agricultural production Multi-span greenhouse Temperature adjustment equipment Cooling capacity Economic benefit
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Doing a Good Job in Inspection and Maintenance of Facilities and Equipments in Bulk Curing Barn
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作者 Yonghua CHEN Hongquan SUN +3 位作者 Pengzhen LONG Guoquan LIU Taiwei LIU Pengyu LU 《Plant Diseases and Pests》 CAS 2022年第3期35-37,共3页
Due to the limited management funds and insufficient management efforts,curing barns in traditional tobacco area are outdated and equipments are seriously damaged,which affects the normal operation and increases the m... Due to the limited management funds and insufficient management efforts,curing barns in traditional tobacco area are outdated and equipments are seriously damaged,which affects the normal operation and increases the maintenance cost of bulk curing barns,bringing adverse effects on tobacco leaf curing in the coming year and the sustainable development of tobacco industry in the future.To ensure the normal operation of curing barns and effectively prolong the service life of curing barns during tobacco leaf curing,we should do a good job in the publicity of management and maintenance,improve the system of management and maintenance,raise funds for management and maintenance,inspect facilities and equipments,carefully maintain equipments in curing barn and strictly perform examination and inspection. 展开更多
关键词 Bulk curing barn Facilities and equipments INSPECTION Maintenance
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Thermoelastoplastic Deformation Analysis of Electromechanical Equipments under Electrocaloric Shock
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作者 于建国 吕晨亮 叶庆泰 《Journal of Donghua University(English Edition)》 EI CAS 2006年第1期42-48,共7页
A coupled thermomechanical model is presented to investigate the thermoelastoplastic deformation mechanism of electromechanical equipments under the condition of electrocaloric shock. In the coupling model, differenti... A coupled thermomechanical model is presented to investigate the thermoelastoplastic deformation mechanism of electromechanical equipments under the condition of electrocaloric shock. In the coupling model, differentiating from the previous analyzing viewpoint that looked upon deformation work as additional heat source, temperature-field equation is established by considering the weakening role of deformation work on the intensity of internal heat source; in the process of setting up displacement-field equation, G-derivative of nonlinear functional is introduced into the traditional theory of elastoplastic finite deformation to simplify the expression of structural stiffness; stress-field equation is constructed by using the least square method to improve the stress solution obtained by constitutive equation. The presented model is converted into finite element program to simulate deforming process of 3-D structures with temperature-dependent material properties. As an example, thermal deformation analysis of Shanghai metro cars’ brake resistor is performed and compared with experimental results for illustrating the validity of the presented model. 展开更多
关键词 electromechanical equipments electro caloric shock thermomechanical coupling finite element analysis.
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Study on Driving Force by Coupling Constraints in NC Equipments Grid
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作者 LUO Ya-bo TANG Ming-chun 《International Journal of Plant Engineering and Management》 2009年第2期90-95,共6页
The burgeoning grid technology provides a practical possibility to share Numerical Control (NC) equipment under a Web environment via many-w-many mode which is faced with the difficulty of a driving force for grid w... The burgeoning grid technology provides a practical possibility to share Numerical Control (NC) equipment under a Web environment via many-w-many mode which is faced with the difficulty of a driving force for grid workflow. This paper proposes the novel methodology of coupling constraints to overcome this difficulty. First, the complex constraints and the structure attributes of NC tasks are detailed in the NC equipment grid that illustrates the possibility of forming a grid workflow force by coupling constraints. Second, the principle of driving force by coupling constraints in an NC equipment grid and the relative algorithm are proposed. Finally, the case study of comparative experiment is detailed to demonstrate the efficiency of this novel tactic. 展开更多
关键词 numerical control grid technology WORKFLOW equipment sharing
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Equipments for Dyeing & Finishing are Facing Low Carbon
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作者 Zhang Shimiao 《China Textile》 2010年第7期52-54,共3页
Dyeing & finishing industry makes it possible for textile products to present colorful world on them.When it beautifies human’s life immensely,it also makes great consumption of energy and resources,and causes en... Dyeing & finishing industry makes it possible for textile products to present colorful world on them.When it beautifies human’s life immensely,it also makes great consumption of energy and resources,and causes environmental pollution. 展开更多
关键词 equipments for Dyeing high DOWN LTD
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Optimization of Maintenance in Civil Aviation Aircraft Equipments
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作者 Gangfeng Wang 《Journal of World Architecture》 2021年第1期26-29,共4页
As the economic level rising,the function and stability of civil aircraft have been greatly improved.However,with the development of science and technology in modern civil aviation transportation,the frequent occurren... As the economic level rising,the function and stability of civil aircraft have been greatly improved.However,with the development of science and technology in modern civil aviation transportation,the frequent occurrence of flight accidents has threatened people’s safety.The main reason is the internal failure of the engine body or the daily maintenance management is incomplete.Therefore,the relevant maintenance management departments should attach great importance to the first core research and management of civil aircraft stability and safety.In view of various equipment problems existing in the operation of civil aircraft,the practical application of data collection mode and maintenance information disclosure mode of modern aircraft maintenance equipment is analyzed.This paper describes some characteristics of aircraft maintenance work,and combined with the main factors affecting the risk of civil aircraft maintenance,giving countermeasures and suggestions to effectively improve the level of civil aircraft maintenance risk management. 展开更多
关键词 Civil aircraft equipMENT Maintenance OPTIMIZATION
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Research progress and future prospects in the service security of key blast furnace equipment
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作者 Yanxiang Liu Kexin Jiao +3 位作者 Jianliang Zhang Cui Wang Lei Zhang Xiaoyue Fan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2121-2135,共15页
The safety and longevity of key blast furnace(BF)equipment determine the stable and low-carbon production of iron.This pa-per presents an analysis of the heat transfer characteristics of these components and the uneve... The safety and longevity of key blast furnace(BF)equipment determine the stable and low-carbon production of iron.This pa-per presents an analysis of the heat transfer characteristics of these components and the uneven distribution of cooling water in parallel pipes based on hydrodynamic principles,discusses the feasible methods for the improvement of BF cooling intensity,and reviews the pre-paration process,performance,and damage characteristics of three key equipment pieces:coolers,tuyeres,and hearth refractories.Fur-thermoere,to attain better control of these critical components under high-temperature working conditions,we propose the application of optimized technologies,such as BF operation and maintenance technology,self-repair technology,and full-lifecycle management techno-logy.Finally,we propose further researches on safety assessments and predictions for key BF equipment under new operating conditions. 展开更多
关键词 blast furnace equipMENT service security blast furnace campaign SELF-REPAIR
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An Improved Solov2 Based on Attention Mechanism and Weighted Loss Function for Electrical Equipment Instance Segmentation
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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
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Project⁃based Pollutant Emission Control of Diesel Construction Equipment
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作者 XIE Yixin FAN Hongqin 《施工技术(中英文)》 CAS 2024年第17期85-93,共9页
This paper examines project⁃based policies and regulations implemented globally to control and mitigate emissions from diesel⁃powered construction equipment.This study systematically reviews and analyzes various manag... This paper examines project⁃based policies and regulations implemented globally to control and mitigate emissions from diesel⁃powered construction equipment.This study systematically reviews and analyzes various managerial,regulatory,and technical measures adopted across countries and regions,mostly of advanced economy.Key strategies of control include setting emission thresholds,idling restrictions,perform remote online monitoring,operational time limits,setting low emission zones,and enforced registration systems.The review highlights the rationale,implementation details,and experiences gained from these localized approaches,reduces localized emission sources,improve urban air quality and environmental management efficiency. 展开更多
关键词 equipMENT diesel emissions CONTROL policy analysis
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Power equipment vibration visualization using intelligent sensing method based on event-sensing principle
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作者 Mingzhe Zhao Xiaojun Shen +1 位作者 Lei Su Zihang Dong 《Global Energy Interconnection》 EI CSCD 2024年第2期228-240,共13页
Vibration measurements can be used to evaluate the operation status of power equipment and are widely applied in equipment quality inspection and fault identification.Event-sensing technology can sense the change in s... Vibration measurements can be used to evaluate the operation status of power equipment and are widely applied in equipment quality inspection and fault identification.Event-sensing technology can sense the change in surface light intensity caused by object vibration and provide a visual description of vibration behavior.Based on the analysis of the principle underlying the transformation of vibration behavior into event flow data by an event sensor,this paper proposes an algorithm to reconstruct event flow data into a relationship correlating vibration displacement and time to extract the amplitude-frequency characteristics of the vibration signal.A vibration measurement test platform is constructed,and feasibility and effectiveness tests are performed for the vibration motor and other power equipment.The results show that event-sensing technology can effectively perceive the surface vibration behavior of power and provide a wide dynamic range.Furthermore,the vibration measurement and visualization algorithm for power equipment constructed using this technology offers high measurement accuracy and efficiency.The results of this study provide a new noncontact and visual method for locating vibrations and performing amplitude-frequency analysis on power equipment. 展开更多
关键词 Power equipment Event sensing Non contact measurement Graphic display FEASIBILITY
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Simplified prediction models for acoustic installation effects of train-mounted equipment
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作者 David Thompson Dong Zhao Giacomo Squicciarini 《Railway Engineering Science》 EI 2024年第2期125-143,共19页
Acoustic models of railway vehicles in standstill and pass-by conditions can be used as part of a virtual certification process for new trains.For each piece of auxiliary equipment,the sound power measured on a test b... Acoustic models of railway vehicles in standstill and pass-by conditions can be used as part of a virtual certification process for new trains.For each piece of auxiliary equipment,the sound power measured on a test bench is combined with meas-ured or predicted transfer functions.It is important,however,to allow for installation effects due to shielding by fairings or the train body.In the current work,fast-running analytical models are developed to determine these installation effects.The model for roof-mounted sources takes account of diffraction at the corner of the train body or fairing,using a barrier model.For equipment mounted under the train,the acoustic propagation from the sides of the source is based on free-field Green’s functions.The bottom surfaces are assumed to radiate initially into a cavity under the train,which is modelled with a simple diffuse field approach.The sound emitted from the gaps at the side of the cavity is then assumed to propagate to the receivers according to free-field Green’s functions.Results show good agreement with a 2.5D boundary element model and with measurements.Modelling uncertainty and parametric uncertainty are evaluated.The largest variability occurs due to the height and impedance of the ground,especially for a low receiver.This leads to standard deviations of up to 4 dB at low frequencies.For the roof-mounted sources,uncertainty over the location of the corner used in the equivalent barrier model can also lead to large standard deviations. 展开更多
关键词 Train noise Auxiliary equipment Acoustic installation effects Virtual certification UNCERTAINTY
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