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
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
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
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
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
I am working in Japan electrical safety & 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 & 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
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
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
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
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
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
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
Given the challenge of estimating or calculating quantities of waste electrical and electronic equipment(WEEE)in developing countries,this article focuses on predicting the WEEE generated by Cameroonian small and medi...Given the challenge of estimating or calculating quantities of waste electrical and electronic equipment(WEEE)in developing countries,this article focuses on predicting the WEEE generated by Cameroonian small and medium enterprises(SMEs)that are engaged in ISO 14001:2015 initiatives and consume electrical and electronic equipment(EEE)to enhance their performance and profitability.The methodology employed an exploratory approach involving the application of general equilibrium theory(GET)to contextualize the study and generate relevant parameters for deploying the random forest regression learning algorithm for predictions.Machine learning was applied to 80%of the samples for training,while simulation was conducted on the remaining 20%of samples based on quantities of EEE utilized over a specific period,utilization rates,repair rates,and average lifespans.The results demonstrate that the model’s predicted values are significantly close to the actual quantities of generated WEEE,and the model’s performance was evaluated using the mean squared error(MSE)and yielding satisfactory results.Based on this model,both companies and stakeholders can set realistic objectives for managing companies’WEEE,fostering sustainable socio-environmental practices.展开更多
A comparison of three hydrometallurgical methods for selective recovery of copper from low-grade electric and electronic wastes was reported. Scraps were smelted to produce Cu?Zn?Sn?Ag alloy. Multiphase material wa...A comparison of three hydrometallurgical methods for selective recovery of copper from low-grade electric and electronic wastes was reported. Scraps were smelted to produce Cu?Zn?Sn?Ag alloy. Multiphase material was analyzed by SEM?EDS and XRD. The alloy was dissolved anodically with simultaneous metal electrodeposition using ammoniacal and sulfuric acid solutions or leached in ammonia?ammonium sulfate solution and then copper electrowinning was carried out. This resulted in the separation of metals, where lead, silver and tin accumulated mainly in the slimes, while copper was transferred to the electrolyte and then recovered on the cathode. The best conditions of the alloy treatment were obtained in the sulfuric acid, where the final product was metal of high purity (99% Cu) at the current efficiency of 90%. Ammoniacal leaching of the alloy led to the accumulation of copper ions in the electrolyte and further metal electrowinning, but the rate of the spontaneous dissolution was low. Anodic dissolution of the alloy in the ammonia?ammonium sulfate solution led to the unfavorable distribution of metals among the slime, electrolyte and cathodic deposit.展开更多
The life of electronic equipment is becoming increasingly shorter and its replacement always generates a quantity of waste increase, giving rise to a problem of environmental character and still needed new options of ...The life of electronic equipment is becoming increasingly shorter and its replacement always generates a quantity of waste increase, giving rise to a problem of environmental character and still needed new options of solid waste management that will contribute to global sustainable development. Parts of these waste are TCI (the card's printed circuit) which containing dangerous elements and turns them into a polluting material from the soil, water and air, being harmful to human health if there is to proper and responsible way, so the recycling of TCI to obtain precious metals is an example of industrial materials that can be recycled. Despite this, large quantities of these are not recycled and some others are not considered. The objective of this work is to present a systematic and ecological methodology for the recovery of valuable materials contained in parts of used in computers, circuit boards using a leaching process. The method determines a set of variables to evaluate the kinetics of the reaction and the leaching of metals that form the substrate of metal and to establish the parameters that affect the rate of leaching of metals through a sensitivity analysis, to identify design alternatives. It determines the quantity and percentages that constitutes the motherboard, processor, video cards, accelerator graphics, network and memory cards RAM, among others and its content of metals such as Cu, Fe, Ag, Au and Pt.展开更多
It is estimated that there is a generation of 307,224 ton/year [1] of waste from electronic and electronic equipment (WEEE) in Mexico, of which 10% is recycled, 40% remains stored and 50% reaches landfills or uncontro...It is estimated that there is a generation of 307,224 ton/year [1] of waste from electronic and electronic equipment (WEEE) in Mexico, of which 10% is recycled, 40% remains stored and 50% reaches landfills or uncontrolled dumps. In the practice, even the regulatory instruments are not consolidated and the adequate management of the use of WEEE management, so the aim of this study is an analysis of life cycle of printed circuit boards (TCI) to identify the management alternatives that represent the least impact to the environment. This assessment was carried out using software SIMAPRO to determine the environmental impact of each scenario, through the comparison of impacts and the proposed improvements to reduce it, following phases of this methodology by applying standards, ISO 14040/ISO 14044 [2], using data from the INE official reports since 2006 until 2010 which concentrate the information of the WEEE problem in Mexico. These data were pooled to carry out inventories according to the availability in the information, identifying the environmental impacts generated by processing. The conclusions of the LCA will serve to identify the stage with greater environmental impact, and thus propose ideas for improvement in order to minimize this impact.展开更多
China stands as one of the leading producers of waste electrical and electronic equipment(WEEE),facing significant challenges in managing the substantial volumes generated.Despite existing regulations,the informal tre...China stands as one of the leading producers of waste electrical and electronic equipment(WEEE),facing significant challenges in managing the substantial volumes generated.Despite existing regulations,the informal treatment of WEEE persists in some areas due to inadequate recycling networks at the city level.Consequently,there is a critical need for a detailed geographical mapping of WEEE generation to address improper disposal practices effectively.This study introduces the cMAC–EEEs(city Material Cycles and Manufactured Capital–EEEs)database,providing estimates of WEEE generation across approximately 300 prefecture-level cities from 1978 to 2017.It focuses on five commonly used types of electrical and electronic equipment(refrigerators,air conditioners,washing machines,computers,TVs)originating from three key sources(urban residents,rural residents,enterprises).The findings reveal(1)significant spatial variation in WEEE generation within China,with eastern and central city clusters identified as hotspots,particularly for urban residents and enterprises,while the western region exhibits the highest growth rate in WEEE generation,notably among rural residents.(2)The growth in obsolete computers and air conditioners is prominent,especially in rural areas and among enterprises,whereas the generation of obsolete TVs,washing machines,and refrigerators is leveling off and expected to decrease in some urban areas.(3)Enterprises account for a substantial portion of WEEE generation,though uncertainties exist,necessitating further refinement.The study highlights that less developed regions lack adequate recycling facilities,with specific limitations in refrigerators and air conditioners recycling capabilities.To enhance WEEE management,it advocates for increased interregional collaboration and capacity building in less developed areas.Additionally,the regulation of WEEE from private enterprises requires improvement.At the product level,a greater focus on recycling practices for refrigerators and air conditioners is recommended.展开更多
The recovery of metals from a multi-component alloy obtained by crushing, melting and anodic dissolution of waste from electric and electronic equipment(WEEE) was investigated. The anodic dissolution of the alloy wa...The recovery of metals from a multi-component alloy obtained by crushing, melting and anodic dissolution of waste from electric and electronic equipment(WEEE) was investigated. The anodic dissolution of the alloy was carried out in an electrolysis cell with one copper cathode and a central cast anode, immersed in the electrolyte formed by choline chloride-ethylene glycol-iodine. The temperature of the electrolyte during the process was 343 K. Depending on the electrolysis parameters(current density and cell voltage), cathodic deposits of Sn, Pb and Zn of 〉99% purity were obtained. Cyclic voltammetry was used in order to determine the deposition potentials of the studied metals. The obtained metallic deposits were subject of determination of XRD, SEM/EDX and AFM in order to evidence the deposits structure and morphology. The experiments performed demonstrated the possibility of separating/selective recovery of metals from the multi-component alloy resulted from the waste from electrical and electronic equipment by anodic dissolution in ionic liquids.展开更多
In addition to maximizing economic benefits, reverse supply chains should further seek to maximize social benefits by increasing the quantity of waste electrical and electronic equipment (WEEE). The paper investigat...In addition to maximizing economic benefits, reverse supply chains should further seek to maximize social benefits by increasing the quantity of waste electrical and electronic equipment (WEEE). The paper investigates cooperative models with different parties in a three-echelon reverse supply chain for WEEE consisting of a single collector, a single remanufacturer, and two retailers based on complete information. In acldition, the optimal decisions of four cooperative models and the effect of the market demand of remanufactured WEEE products and the market share of two retailers on the optimal decisions are discussed. The results indicate that optimal total channel profit and recycle quantity in a reverse supply chain are maximized in a centralized model. The optimal total channel profit and recycle quantity increase with an increase in the market demand of remanufactured WEEE products. The three-echelon reverse supply chain consisting of duopolistic retailers maximizes total channel profit and recycle quantity in a reverse supply chain fbr WEEE.展开更多
基金Jilin Science and Technology Development Plan Project(No.20200403075SF)Doctoral Research Start-Up Fund of Northeast Electric Power University(No.BSJXM-2018202).
文摘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.
文摘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.
基金supported by the Youth Foundation of the National Natural Science Foundation of China(Grant No.51509252)。
文摘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.
基金Scientific Research Fund of IEM,CEA under Grant Nos.2016B09,2014B12China Natural Science Foundation under Grant Nos.51478442,51408565
文摘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.
基金This research was funded by science and technology project of State Grid JiangSu Electric Power Co.,Ltd.(Research on Key Technologies of power network security digital identity authentication and management and control based on blockchain,Grant No.is J2021021).
文摘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.
文摘I am working in Japan electrical safety & 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.
文摘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
基金funded by the special project of Spark Program of Earthquake Sciences (Serial number:XH12063)
文摘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.
文摘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.
基金founded by the Earthquake Science and Technology Spark Plan of China(XH12063)
文摘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.
文摘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.
文摘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.
文摘Given the challenge of estimating or calculating quantities of waste electrical and electronic equipment(WEEE)in developing countries,this article focuses on predicting the WEEE generated by Cameroonian small and medium enterprises(SMEs)that are engaged in ISO 14001:2015 initiatives and consume electrical and electronic equipment(EEE)to enhance their performance and profitability.The methodology employed an exploratory approach involving the application of general equilibrium theory(GET)to contextualize the study and generate relevant parameters for deploying the random forest regression learning algorithm for predictions.Machine learning was applied to 80%of the samples for training,while simulation was conducted on the remaining 20%of samples based on quantities of EEE utilized over a specific period,utilization rates,repair rates,and average lifespans.The results demonstrate that the model’s predicted values are significantly close to the actual quantities of generated WEEE,and the model’s performance was evaluated using the mean squared error(MSE)and yielding satisfactory results.Based on this model,both companies and stakeholders can set realistic objectives for managing companies’WEEE,fostering sustainable socio-environmental practices.
基金supported by National Natural Science Foundation of China(61533013,61273144)Scientific Technology Research and Development Plan Project of Tangshan(13130298B)Scientific Technology Research and Development Plan Project of Hebei(z2014070)
基金Project(NNOTECH-2/IN2/18/181960/NCBR)supported by the National Centre for Research and Development,Poland
文摘A comparison of three hydrometallurgical methods for selective recovery of copper from low-grade electric and electronic wastes was reported. Scraps were smelted to produce Cu?Zn?Sn?Ag alloy. Multiphase material was analyzed by SEM?EDS and XRD. The alloy was dissolved anodically with simultaneous metal electrodeposition using ammoniacal and sulfuric acid solutions or leached in ammonia?ammonium sulfate solution and then copper electrowinning was carried out. This resulted in the separation of metals, where lead, silver and tin accumulated mainly in the slimes, while copper was transferred to the electrolyte and then recovered on the cathode. The best conditions of the alloy treatment were obtained in the sulfuric acid, where the final product was metal of high purity (99% Cu) at the current efficiency of 90%. Ammoniacal leaching of the alloy led to the accumulation of copper ions in the electrolyte and further metal electrowinning, but the rate of the spontaneous dissolution was low. Anodic dissolution of the alloy in the ammonia?ammonium sulfate solution led to the unfavorable distribution of metals among the slime, electrolyte and cathodic deposit.
文摘The life of electronic equipment is becoming increasingly shorter and its replacement always generates a quantity of waste increase, giving rise to a problem of environmental character and still needed new options of solid waste management that will contribute to global sustainable development. Parts of these waste are TCI (the card's printed circuit) which containing dangerous elements and turns them into a polluting material from the soil, water and air, being harmful to human health if there is to proper and responsible way, so the recycling of TCI to obtain precious metals is an example of industrial materials that can be recycled. Despite this, large quantities of these are not recycled and some others are not considered. The objective of this work is to present a systematic and ecological methodology for the recovery of valuable materials contained in parts of used in computers, circuit boards using a leaching process. The method determines a set of variables to evaluate the kinetics of the reaction and the leaching of metals that form the substrate of metal and to establish the parameters that affect the rate of leaching of metals through a sensitivity analysis, to identify design alternatives. It determines the quantity and percentages that constitutes the motherboard, processor, video cards, accelerator graphics, network and memory cards RAM, among others and its content of metals such as Cu, Fe, Ag, Au and Pt.
文摘It is estimated that there is a generation of 307,224 ton/year [1] of waste from electronic and electronic equipment (WEEE) in Mexico, of which 10% is recycled, 40% remains stored and 50% reaches landfills or uncontrolled dumps. In the practice, even the regulatory instruments are not consolidated and the adequate management of the use of WEEE management, so the aim of this study is an analysis of life cycle of printed circuit boards (TCI) to identify the management alternatives that represent the least impact to the environment. This assessment was carried out using software SIMAPRO to determine the environmental impact of each scenario, through the comparison of impacts and the proposed improvements to reduce it, following phases of this methodology by applying standards, ISO 14040/ISO 14044 [2], using data from the INE official reports since 2006 until 2010 which concentrate the information of the WEEE problem in Mexico. These data were pooled to carry out inventories according to the availability in the information, identifying the environmental impacts generated by processing. The conclusions of the LCA will serve to identify the stage with greater environmental impact, and thus propose ideas for improvement in order to minimize this impact.
基金supported by the Strategic Pilot Science and Technology Projects of Chinese Academy of Sciences(XDA23030304)the National Natural Science Foundation of China(Grant Nos.52200214,71961147003,and 52070178)+1 种基金Key Program of Frontier Science of the Chinese Academy of Sciences(QYZDB-SSW-DQC012)the China Scholarship Council(Grant No.201904910422).
文摘China stands as one of the leading producers of waste electrical and electronic equipment(WEEE),facing significant challenges in managing the substantial volumes generated.Despite existing regulations,the informal treatment of WEEE persists in some areas due to inadequate recycling networks at the city level.Consequently,there is a critical need for a detailed geographical mapping of WEEE generation to address improper disposal practices effectively.This study introduces the cMAC–EEEs(city Material Cycles and Manufactured Capital–EEEs)database,providing estimates of WEEE generation across approximately 300 prefecture-level cities from 1978 to 2017.It focuses on five commonly used types of electrical and electronic equipment(refrigerators,air conditioners,washing machines,computers,TVs)originating from three key sources(urban residents,rural residents,enterprises).The findings reveal(1)significant spatial variation in WEEE generation within China,with eastern and central city clusters identified as hotspots,particularly for urban residents and enterprises,while the western region exhibits the highest growth rate in WEEE generation,notably among rural residents.(2)The growth in obsolete computers and air conditioners is prominent,especially in rural areas and among enterprises,whereas the generation of obsolete TVs,washing machines,and refrigerators is leveling off and expected to decrease in some urban areas.(3)Enterprises account for a substantial portion of WEEE generation,though uncertainties exist,necessitating further refinement.The study highlights that less developed regions lack adequate recycling facilities,with specific limitations in refrigerators and air conditioners recycling capabilities.To enhance WEEE management,it advocates for increased interregional collaboration and capacity building in less developed areas.Additionally,the regulation of WEEE from private enterprises requires improvement.At the product level,a greater focus on recycling practices for refrigerators and air conditioners is recommended.
文摘The recovery of metals from a multi-component alloy obtained by crushing, melting and anodic dissolution of waste from electric and electronic equipment(WEEE) was investigated. The anodic dissolution of the alloy was carried out in an electrolysis cell with one copper cathode and a central cast anode, immersed in the electrolyte formed by choline chloride-ethylene glycol-iodine. The temperature of the electrolyte during the process was 343 K. Depending on the electrolysis parameters(current density and cell voltage), cathodic deposits of Sn, Pb and Zn of 〉99% purity were obtained. Cyclic voltammetry was used in order to determine the deposition potentials of the studied metals. The obtained metallic deposits were subject of determination of XRD, SEM/EDX and AFM in order to evidence the deposits structure and morphology. The experiments performed demonstrated the possibility of separating/selective recovery of metals from the multi-component alloy resulted from the waste from electrical and electronic equipment by anodic dissolution in ionic liquids.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 71471105).
文摘In addition to maximizing economic benefits, reverse supply chains should further seek to maximize social benefits by increasing the quantity of waste electrical and electronic equipment (WEEE). The paper investigates cooperative models with different parties in a three-echelon reverse supply chain for WEEE consisting of a single collector, a single remanufacturer, and two retailers based on complete information. In acldition, the optimal decisions of four cooperative models and the effect of the market demand of remanufactured WEEE products and the market share of two retailers on the optimal decisions are discussed. The results indicate that optimal total channel profit and recycle quantity in a reverse supply chain are maximized in a centralized model. The optimal total channel profit and recycle quantity increase with an increase in the market demand of remanufactured WEEE products. The three-echelon reverse supply chain consisting of duopolistic retailers maximizes total channel profit and recycle quantity in a reverse supply chain fbr WEEE.