Pub Date : 2006-05-08DOI: 10.1109/ISEE.2006.1650047
A. Murray, Yong Li
Permanent magnet motors are commonly used in AC inverter controlled air conditioner systems for home appliances. Acoustic noise and vibration reduction in the outdoor unit compressor is an important task, in addition to attaining high efficiency power usage. It is also required to eliminate motor position sensors such as Hall effect sensors due to the structural constraint of sealed compressors. These requirements naturally lead manufacturers to incorporate sinusoidal sensor-less PM motor control. Today, most air conditioner units are based on 32 bit RISC microcontrollers to achieve compressor motor control. In outdoor unit air conditioners, not only does the compressor use an AC inverter but also the fan uses an AC inverter. The fan is also based on a PM motor and its control is based on Hall effect sensors in today's system. Power factor control is also required for a certain power range of air conditioner, which has normally been implemented by separate analog PFC control IC. This paper discusses a hardware computation-based dedicated controller for air conditioner applications that enables sinusoidal sensorless PM motor control for both compressor and fan, and digital PFC within a single monolithic silicon platform. Sensorless field oriented control (FOC) is implemented using an embedded motion control engine (MCE) so that computation power can be attained with two motor FOC controls and digital PFC combined
{"title":"Motion Control Engine Achieves High Efficiency with Digital PFC Integration in Air Conditioner Applications","authors":"A. Murray, Yong Li","doi":"10.1109/ISEE.2006.1650047","DOIUrl":"https://doi.org/10.1109/ISEE.2006.1650047","url":null,"abstract":"Permanent magnet motors are commonly used in AC inverter controlled air conditioner systems for home appliances. Acoustic noise and vibration reduction in the outdoor unit compressor is an important task, in addition to attaining high efficiency power usage. It is also required to eliminate motor position sensors such as Hall effect sensors due to the structural constraint of sealed compressors. These requirements naturally lead manufacturers to incorporate sinusoidal sensor-less PM motor control. Today, most air conditioner units are based on 32 bit RISC microcontrollers to achieve compressor motor control. In outdoor unit air conditioners, not only does the compressor use an AC inverter but also the fan uses an AC inverter. The fan is also based on a PM motor and its control is based on Hall effect sensors in today's system. Power factor control is also required for a certain power range of air conditioner, which has normally been implemented by separate analog PFC control IC. This paper discusses a hardware computation-based dedicated controller for air conditioner applications that enables sinusoidal sensorless PM motor control for both compressor and fan, and digital PFC within a single monolithic silicon platform. Sensorless field oriented control (FOC) is implemented using an embedded motion control engine (MCE) so that computation power can be attained with two motor FOC controls and digital PFC combined","PeriodicalId":141255,"journal":{"name":"Proceedings of the 2006 IEEE International Symposium on Electronics and the Environment, 2006.","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115244362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-05-08DOI: 10.1109/ISEE.2006.1650050
J. Gregory, J. Atlee, R. Kirchain
This paper describes a model of end-of-life electronics recycling that uses process-based cost modeling and value-based metrics to determine the economic and value-recovery effectiveness of a processing operation. The process-based cost models combine engineering process models, operational models, and an economic framework to map from details of product and process to operating costs. The value-weighted mass recovery assessments, when compared against simple mass recovered, provide a better estimate of both environmental impact and retained quality. The combination of these two aspects offers several advantages over existing modeling methodologies: they consider the variety of products a recycler processes, are driven by data that a recycler collects, and can respond to rapidly changing conditions. Background on these aspects is provided, followed by a description of the modeling framework. An example case involving cathode ray tubes is presented to depict the type of analyses possible using the model
{"title":"A Process-Based Model of End-of-Life Electronics Recycling Driving Eco-Efficiency-Informed Decisions","authors":"J. Gregory, J. Atlee, R. Kirchain","doi":"10.1109/ISEE.2006.1650050","DOIUrl":"https://doi.org/10.1109/ISEE.2006.1650050","url":null,"abstract":"This paper describes a model of end-of-life electronics recycling that uses process-based cost modeling and value-based metrics to determine the economic and value-recovery effectiveness of a processing operation. The process-based cost models combine engineering process models, operational models, and an economic framework to map from details of product and process to operating costs. The value-weighted mass recovery assessments, when compared against simple mass recovered, provide a better estimate of both environmental impact and retained quality. The combination of these two aspects offers several advantages over existing modeling methodologies: they consider the variety of products a recycler processes, are driven by data that a recycler collects, and can respond to rapidly changing conditions. Background on these aspects is provided, followed by a description of the modeling framework. An example case involving cathode ray tubes is presented to depict the type of analyses possible using the model","PeriodicalId":141255,"journal":{"name":"Proceedings of the 2006 IEEE International Symposium on Electronics and the Environment, 2006.","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128674097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-05-08DOI: 10.1109/ISEE.2006.1650062
J. Dahmus, T. Gutowski
This work focuses on developing a compact representation of the material recycling potential for products at end-of-life. This representation is based on two measures: the value of the materials used in a product and the mixture of materials used in a product. These measures are similar to those used in constructing the Sherwood plot, which relates metal prices to the concentration of metals in a given ore grade. While the Sherwood plot provides insight into the relative attractiveness of mining different ores, the work here provides insight into the relative attractiveness of recycling different products. This information can in turn be used to help guide both product design and recycling policy
{"title":"Material Recycling at Product End-of-Life","authors":"J. Dahmus, T. Gutowski","doi":"10.1109/ISEE.2006.1650062","DOIUrl":"https://doi.org/10.1109/ISEE.2006.1650062","url":null,"abstract":"This work focuses on developing a compact representation of the material recycling potential for products at end-of-life. This representation is based on two measures: the value of the materials used in a product and the mixture of materials used in a product. These measures are similar to those used in constructing the Sherwood plot, which relates metal prices to the concentration of metals in a given ore grade. While the Sherwood plot provides insight into the relative attractiveness of mining different ores, the work here provides insight into the relative attractiveness of recycling different products. This information can in turn be used to help guide both product design and recycling policy","PeriodicalId":141255,"journal":{"name":"Proceedings of the 2006 IEEE International Symposium on Electronics and the Environment, 2006.","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121150213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-05-08DOI: 10.1109/ISEE.2006.1650049
P. Bohr
Several countries across the globe have implemented or are about to implement specific electronics recycling regulations based on the principle of extended producer responsibility (EPR). Both existing and proposed solutions are implemented with various degrees of centralization; one solution involves a steering regulatory authority, another connects the EPR with strong competitive market structures. As different WEEE recycling approaches evolve, the best way to achieve a cost- and eco-efficient system organization is still contentious. Theoretical system characteristics intended by policy-makers and their realization in practice often don't coincide. Practical implementations can give rise to absurd organizational outcomes. Some incentive structures are counterproductive, and actual environmental purposes of recycling legislation are often poorly reflected. This paper presents a specific certificate market tool that potentially has intriguing properties in terms of system performance, control, organization and cost. The approach introduces competition on several levels in the value chain and sets incentives for the eco-efficient treatment of WEEE. In addition, it enables decentralized decision-making which is one of the key levers for a cost-efficient system organization in a competitive market setting
{"title":"Policy Tools for Electronics Recycling Characteristics of a specific certificate market design","authors":"P. Bohr","doi":"10.1109/ISEE.2006.1650049","DOIUrl":"https://doi.org/10.1109/ISEE.2006.1650049","url":null,"abstract":"Several countries across the globe have implemented or are about to implement specific electronics recycling regulations based on the principle of extended producer responsibility (EPR). Both existing and proposed solutions are implemented with various degrees of centralization; one solution involves a steering regulatory authority, another connects the EPR with strong competitive market structures. As different WEEE recycling approaches evolve, the best way to achieve a cost- and eco-efficient system organization is still contentious. Theoretical system characteristics intended by policy-makers and their realization in practice often don't coincide. Practical implementations can give rise to absurd organizational outcomes. Some incentive structures are counterproductive, and actual environmental purposes of recycling legislation are often poorly reflected. This paper presents a specific certificate market tool that potentially has intriguing properties in terms of system performance, control, organization and cost. The approach introduces competition on several levels in the value chain and sets incentives for the eco-efficient treatment of WEEE. In addition, it enables decentralized decision-making which is one of the key levers for a cost-efficient system organization in a competitive market setting","PeriodicalId":141255,"journal":{"name":"Proceedings of the 2006 IEEE International Symposium on Electronics and the Environment, 2006.","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121775234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-05-08DOI: 10.1109/ISEE.2006.1650077
M. Streicher-Porte
Waste of electrical and electronic equipment, otherwise known as e-waste, is one of the fastest growing fractions in the worldwide municipal waste stream. As this e-waste contains valuable resources which can be easily recycled, as well as hazardous substances which have to be treated in an environmentally sound manner, many countries have launched programs to deal with this challenge. These recycling systems have to be cost efficient and recover material or energy whilst still complying with environmental standards. Switzerland has two such e-waste recycling systems which were established on a voluntary basis and have been operating since 1991. This paper evaluates the historical data of one system: SWICO, and assesses the development of the system's costs. It also forecasts the development of waste volume for personal computers until the year 2020. During the setting up of SWICO many pragmatic decisions had to be made, one of which resulted in the introduction of an advanced recycling fee on sales for each electronic item. From 1994 to the present moment, SWICO has expanded its activity, lowered its fees and increased its return rate to almost 100%. In this work a comparison is made between SWICO and a similar e-waste system from Norway. Although the two systems differ somewhat in their calculation of recycling reimbursement $the Norwegian system couples these costs to actual metal and plastic prices oth systems have achieved high return rates and have lowered advanced recycling fees. They are also accepted nationwide and comply with high environmental standards. In addition to this, the Norwegian system boasts the lowest fees in Europe whilst still maintaining a high degree of transparency
{"title":"SWICO/S.EN.S, the Swiss WEEE recycling systems and best practices from other European systems","authors":"M. Streicher-Porte","doi":"10.1109/ISEE.2006.1650077","DOIUrl":"https://doi.org/10.1109/ISEE.2006.1650077","url":null,"abstract":"Waste of electrical and electronic equipment, otherwise known as e-waste, is one of the fastest growing fractions in the worldwide municipal waste stream. As this e-waste contains valuable resources which can be easily recycled, as well as hazardous substances which have to be treated in an environmentally sound manner, many countries have launched programs to deal with this challenge. These recycling systems have to be cost efficient and recover material or energy whilst still complying with environmental standards. Switzerland has two such e-waste recycling systems which were established on a voluntary basis and have been operating since 1991. This paper evaluates the historical data of one system: SWICO, and assesses the development of the system's costs. It also forecasts the development of waste volume for personal computers until the year 2020. During the setting up of SWICO many pragmatic decisions had to be made, one of which resulted in the introduction of an advanced recycling fee on sales for each electronic item. From 1994 to the present moment, SWICO has expanded its activity, lowered its fees and increased its return rate to almost 100%. In this work a comparison is made between SWICO and a similar e-waste system from Norway. Although the two systems differ somewhat in their calculation of recycling reimbursement $the Norwegian system couples these costs to actual metal and plastic prices oth systems have achieved high return rates and have lowered advanced recycling fees. They are also accepted nationwide and comply with high environmental standards. In addition to this, the Norwegian system boasts the lowest fees in Europe whilst still maintaining a high degree of transparency","PeriodicalId":141255,"journal":{"name":"Proceedings of the 2006 IEEE International Symposium on Electronics and the Environment, 2006.","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126477362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-05-08DOI: 10.1109/ISEE.2006.1650021
J. Cooper, J. Fava
A survey of life cycle assessment practitioners and a review of related methodological advances and capacity building activities are used to understand LCA advancements for evolutionary and revolutionary electronic products. Issues and recommendations for database, tool development, and methodological issues specific to electronics products are highlighted and discussed. We conclude that electronics sector participation in current LCA initiatives can highlight issues in a way that fosters advancement.
{"title":"The life cycle assessment practitioners survey: assessment methods for evolutionary and revolutionary electronic products","authors":"J. Cooper, J. Fava","doi":"10.1109/ISEE.2006.1650021","DOIUrl":"https://doi.org/10.1109/ISEE.2006.1650021","url":null,"abstract":"A survey of life cycle assessment practitioners and a review of related methodological advances and capacity building activities are used to understand LCA advancements for evolutionary and revolutionary electronic products. Issues and recommendations for database, tool development, and methodological issues specific to electronics products are highlighted and discussed. We conclude that electronics sector participation in current LCA initiatives can highlight issues in a way that fosters advancement.","PeriodicalId":141255,"journal":{"name":"Proceedings of the 2006 IEEE International Symposium on Electronics and the Environment, 2006.","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127257086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-05-08DOI: 10.1109/ISEE.2006.1650032
J. Herkert
Professional engineering societies and corporations respond in a variety of ways to the challenges of sustainable development. This paper dissects several prominent organizations and the ethical aspects of their responses, which range from ignoring sustainability concerns, to green washing, to measurement of triple bottom line performance, to altering the strategic objectives of the organization
{"title":"Ethical responses of large organizations to the challenge of substainable development","authors":"J. Herkert","doi":"10.1109/ISEE.2006.1650032","DOIUrl":"https://doi.org/10.1109/ISEE.2006.1650032","url":null,"abstract":"Professional engineering societies and corporations respond in a variety of ways to the challenges of sustainable development. This paper dissects several prominent organizations and the ethical aspects of their responses, which range from ignoring sustainability concerns, to green washing, to measurement of triple bottom line performance, to altering the strategic objectives of the organization","PeriodicalId":141255,"journal":{"name":"Proceedings of the 2006 IEEE International Symposium on Electronics and the Environment, 2006.","volume":"133 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127304478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-05-08DOI: 10.1109/ISEE.2006.1650037
F. Kommonen, S. Rhodes
During 2003-2004, the Canadian Electricity Association sponsored a study to test the application of the environmental life cycle impact assessment on various power generation technologies, including, but not limited to, coal generation, wind power, natural gas, and hydropower facilities. This paper discusses the goal and scope of the study, key methodological issues, key findings, and policy implications of these pilot studies. Through the integration of advanced impact assessment techniques, the study provides a benchmark for similar studies including those of the western area power authority and suggests counterintuitive results for wind power and coal technology operations. Additionally, the application of the methodologies toward the development of the ASTM E06.71.10 draft standard and the UNEP/SETAC LCIA initiative will be covered
{"title":"Use of Environmental Life Cycle Impact Assessment for Power Generation Systems: Canadian Electricity Association Case Study","authors":"F. Kommonen, S. Rhodes","doi":"10.1109/ISEE.2006.1650037","DOIUrl":"https://doi.org/10.1109/ISEE.2006.1650037","url":null,"abstract":"During 2003-2004, the Canadian Electricity Association sponsored a study to test the application of the environmental life cycle impact assessment on various power generation technologies, including, but not limited to, coal generation, wind power, natural gas, and hydropower facilities. This paper discusses the goal and scope of the study, key methodological issues, key findings, and policy implications of these pilot studies. Through the integration of advanced impact assessment techniques, the study provides a benchmark for similar studies including those of the western area power authority and suggests counterintuitive results for wind power and coal technology operations. Additionally, the application of the methodologies toward the development of the ASTM E06.71.10 draft standard and the UNEP/SETAC LCIA initiative will be covered","PeriodicalId":141255,"journal":{"name":"Proceedings of the 2006 IEEE International Symposium on Electronics and the Environment, 2006.","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123931873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-05-08DOI: 10.1109/ISEE.2006.1650026
T. Brady, S. Brown, D. Depaoli, J. Solomon, T. Wooldridge
Nanotechnology is and will be the foundation for exciting new technologies for years to come. Much of nanotechnology's promise is related to the unique properties that materials exhibit on the nanoscale. With such promise come questions concerning the environmental, safety and health (ESH) of the new technologies. As a result, a cross functional team of ESH experts from the chemical and semiconductor industries, with inputs from academic and governmental representatives, reviewed existing ESH and nanotechnology research and developed a list of over 30 research areas where ESH questions were unanswered. From this list, the top five research needs were identified and further explored based on the expertise of the team.
{"title":"ESH & Nanotechnology: A Joint Study by the Chemical Industry Vision2020 and the Semiconductor Research Corporation","authors":"T. Brady, S. Brown, D. Depaoli, J. Solomon, T. Wooldridge","doi":"10.1109/ISEE.2006.1650026","DOIUrl":"https://doi.org/10.1109/ISEE.2006.1650026","url":null,"abstract":"Nanotechnology is and will be the foundation for exciting new technologies for years to come. Much of nanotechnology's promise is related to the unique properties that materials exhibit on the nanoscale. With such promise come questions concerning the environmental, safety and health (ESH) of the new technologies. As a result, a cross functional team of ESH experts from the chemical and semiconductor industries, with inputs from academic and governmental representatives, reviewed existing ESH and nanotechnology research and developed a list of over 30 research areas where ESH questions were unanswered. From this list, the top five research needs were identified and further explored based on the expertise of the team.","PeriodicalId":141255,"journal":{"name":"Proceedings of the 2006 IEEE International Symposium on Electronics and the Environment, 2006.","volume":"124 10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124658271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-05-08DOI: 10.1109/ISEE.2006.1650083
X. Wen, Jinhui Li, L. Hao, Fengfii Yin, Lixiao Hu, Heping Liu, Zhenyu Liu
E-waste problem is a worldwide conundrum. China, as an important production, consumption and export country of electrical and electronic equipments face great pressure on e-waste recycling. This paper introduced the current situations of e-waste and reviewed various technologies and different scale facilities of e-waste recycling existed in China. The challenges for government, original equipment manufacturers and recyclers were analyzed based on the situations of China and the global. At last corresponding countermeasures which have been and will be implemented are presented to promote environmentally sound management of e-waste recycling of China
{"title":"An Agenda to Move Forward E-waste Recycling and Challenges in China","authors":"X. Wen, Jinhui Li, L. Hao, Fengfii Yin, Lixiao Hu, Heping Liu, Zhenyu Liu","doi":"10.1109/ISEE.2006.1650083","DOIUrl":"https://doi.org/10.1109/ISEE.2006.1650083","url":null,"abstract":"E-waste problem is a worldwide conundrum. China, as an important production, consumption and export country of electrical and electronic equipments face great pressure on e-waste recycling. This paper introduced the current situations of e-waste and reviewed various technologies and different scale facilities of e-waste recycling existed in China. The challenges for government, original equipment manufacturers and recyclers were analyzed based on the situations of China and the global. At last corresponding countermeasures which have been and will be implemented are presented to promote environmentally sound management of e-waste recycling of China","PeriodicalId":141255,"journal":{"name":"Proceedings of the 2006 IEEE International Symposium on Electronics and the Environment, 2006.","volume":"157 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127363627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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