Pub Date : 2013-05-21DOI: 10.1109/ENERGYTECH.2013.6645338
Annette E. Trippe, Tobias Massier, T. Hamacher
With an increasing market share of electric vehicles (EVs) the question of additional electricity demand and its effects arises. In this context, smart charging of EVs is discussed. This paper investigates the optimization of charging strategies with cost as objective function. Thereby, battery constraints regarding the charging process are taken into account. The problem is formulated as a mixed integer linear programming problem. The model accesses detailed information on battery charging profiles, predefining charging energy amount as well as charging current and voltage. Beside the battery constraints, limitations by the EV drivers' mobility demand as well as maximum power limitations of the investigated system are considered. Within the framework of a case study for Singapore, the model is applied to a sample of EVs and to the corresponding car parks, resulting in charging power profiles for different car park types.
{"title":"Optimized charging of electric vehicles with regard to battery constraints - Case study: Singaporean car park","authors":"Annette E. Trippe, Tobias Massier, T. Hamacher","doi":"10.1109/ENERGYTECH.2013.6645338","DOIUrl":"https://doi.org/10.1109/ENERGYTECH.2013.6645338","url":null,"abstract":"With an increasing market share of electric vehicles (EVs) the question of additional electricity demand and its effects arises. In this context, smart charging of EVs is discussed. This paper investigates the optimization of charging strategies with cost as objective function. Thereby, battery constraints regarding the charging process are taken into account. The problem is formulated as a mixed integer linear programming problem. The model accesses detailed information on battery charging profiles, predefining charging energy amount as well as charging current and voltage. Beside the battery constraints, limitations by the EV drivers' mobility demand as well as maximum power limitations of the investigated system are considered. Within the framework of a case study for Singapore, the model is applied to a sample of EVs and to the corresponding car parks, resulting in charging power profiles for different car park types.","PeriodicalId":154402,"journal":{"name":"2013 IEEE Energytech","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127675500","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 : 2013-05-21DOI: 10.1109/ENERGYTECH.2013.6645328
F. Cheng, W. Greenwood, B. Arellano, J. Hawkins, O. Lavrova, A. Mammoli, S. Willard
Battery Energy Storage Systems play a vital role in assisting high penetration photovoltaic (PV) connections to the power grid. The development of PV, has led to concern about related reliability issues and due to inherent characteristics of PV intermittency. It has also led to investigation of using storage systems to better control renewable resources. A Smart Grid demonstration project is currently underway at Public Service Company of New Mexico (PNM). The project combines both residential and commercial loads on a dedicated feeder, equipped with a utility scale 0.5MW photovoltaic (PV) system and large-scale utility based Battery Energy Storage System (BESS). This project is investing how PV works with Energy Storage to benefit the power grid. In this paper, we present how to use BESS to firm PV output, and at the same time align the PV output with peak load. The control strategy and current results of modeling for the existing infrastructure of this Smart Grid project are given.
{"title":"Maximizing the benefits of PV utility scale storage at PNM prosperity project","authors":"F. Cheng, W. Greenwood, B. Arellano, J. Hawkins, O. Lavrova, A. Mammoli, S. Willard","doi":"10.1109/ENERGYTECH.2013.6645328","DOIUrl":"https://doi.org/10.1109/ENERGYTECH.2013.6645328","url":null,"abstract":"Battery Energy Storage Systems play a vital role in assisting high penetration photovoltaic (PV) connections to the power grid. The development of PV, has led to concern about related reliability issues and due to inherent characteristics of PV intermittency. It has also led to investigation of using storage systems to better control renewable resources. A Smart Grid demonstration project is currently underway at Public Service Company of New Mexico (PNM). The project combines both residential and commercial loads on a dedicated feeder, equipped with a utility scale 0.5MW photovoltaic (PV) system and large-scale utility based Battery Energy Storage System (BESS). This project is investing how PV works with Energy Storage to benefit the power grid. In this paper, we present how to use BESS to firm PV output, and at the same time align the PV output with peak load. The control strategy and current results of modeling for the existing infrastructure of this Smart Grid project are given.","PeriodicalId":154402,"journal":{"name":"2013 IEEE Energytech","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127993241","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 : 2013-05-21DOI: 10.1109/ENERGYTECH.2013.6645283
Amit Singh, S. Parida
Distributed generation (DG) has emerged as a key issue for the sustainable development in near future. In the literature, many researchers were introducing about DG placement considering various criteria. These DGs can be of conventional and renewable energy sources (RESs). Under these circumstances, if only wind energy based DG would be placed at the appropriate locations in the particular region of the network. In this situation, high noise will be created in those regions. To overcome this problem, it is necessary to allocate some other energy sources in those regions. From these points of view, system operators and policy makers to deal with such impact in the restructured electricity market to identify the adoptable and unadoptable DGs based on technical, economical, environmental and resource availability aspects has been discussed.
{"title":"A new selection criteria for combined optimal allocation of RESs based DGs in restructured electricity market","authors":"Amit Singh, S. Parida","doi":"10.1109/ENERGYTECH.2013.6645283","DOIUrl":"https://doi.org/10.1109/ENERGYTECH.2013.6645283","url":null,"abstract":"Distributed generation (DG) has emerged as a key issue for the sustainable development in near future. In the literature, many researchers were introducing about DG placement considering various criteria. These DGs can be of conventional and renewable energy sources (RESs). Under these circumstances, if only wind energy based DG would be placed at the appropriate locations in the particular region of the network. In this situation, high noise will be created in those regions. To overcome this problem, it is necessary to allocate some other energy sources in those regions. From these points of view, system operators and policy makers to deal with such impact in the restructured electricity market to identify the adoptable and unadoptable DGs based on technical, economical, environmental and resource availability aspects has been discussed.","PeriodicalId":154402,"journal":{"name":"2013 IEEE Energytech","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132247803","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 : 2013-05-21DOI: 10.1109/ENERGYTECH.2013.6645310
F. Maturana, R. Staron, D. Carnahan, K. Loparo
Power grids by their nature occupy a large geographical area, and any robust, intelligent control system for these grids needs to be distributed as well. Moreover, the increase in both the number and types of intelligent power consumer devices and the number and variation in renewable power sources presents new challenges and opportunities for more intelligent control. In this paper, the authors use a small scale model for such a DC micro-power grid to implement and test several intelligent control algorithms. These are implemented using a combination of real-time control and intelligent agents. Each distributed algorithm is described and preliminary results from this testing have provided important advances toward an understanding of information management in highly dynamic distributed power systems.
{"title":"Distributed control concepts for future power grids","authors":"F. Maturana, R. Staron, D. Carnahan, K. Loparo","doi":"10.1109/ENERGYTECH.2013.6645310","DOIUrl":"https://doi.org/10.1109/ENERGYTECH.2013.6645310","url":null,"abstract":"Power grids by their nature occupy a large geographical area, and any robust, intelligent control system for these grids needs to be distributed as well. Moreover, the increase in both the number and types of intelligent power consumer devices and the number and variation in renewable power sources presents new challenges and opportunities for more intelligent control. In this paper, the authors use a small scale model for such a DC micro-power grid to implement and test several intelligent control algorithms. These are implemented using a combination of real-time control and intelligent agents. Each distributed algorithm is described and preliminary results from this testing have provided important advances toward an understanding of information management in highly dynamic distributed power systems.","PeriodicalId":154402,"journal":{"name":"2013 IEEE Energytech","volume":"188 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128642415","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 : 2013-05-21DOI: 10.1109/ENERGYTECH.2013.6645320
M. N. Arafat, A. Elrayyah, Y. Sozer
This paper proposes a smooth transition control strategy for voltage source inverters between standalone (SA) and grid connected (GC) modes of operation. During transition both current control and droop control will participate in formulating the inverter output voltage but with different weights or coefficients. In transition mode the controller varies the output coefficients of the current and droop control depending on the frequency variation to regulate the real power flow. In the proposed controller, no additional unit, like central controller, is needed to flow the required power in the transition period and no explicit communication between the inverters is required. In the transition mode, the proposed controller takes the responsibility and ensures the continuous power delivery to the load. The performance of the proposed control technique has been verified with simulation and experimental studies.
{"title":"Hybrid droop and current control for seamless transition mode of microgrids","authors":"M. N. Arafat, A. Elrayyah, Y. Sozer","doi":"10.1109/ENERGYTECH.2013.6645320","DOIUrl":"https://doi.org/10.1109/ENERGYTECH.2013.6645320","url":null,"abstract":"This paper proposes a smooth transition control strategy for voltage source inverters between standalone (SA) and grid connected (GC) modes of operation. During transition both current control and droop control will participate in formulating the inverter output voltage but with different weights or coefficients. In transition mode the controller varies the output coefficients of the current and droop control depending on the frequency variation to regulate the real power flow. In the proposed controller, no additional unit, like central controller, is needed to flow the required power in the transition period and no explicit communication between the inverters is required. In the transition mode, the proposed controller takes the responsibility and ensures the continuous power delivery to the load. The performance of the proposed control technique has been verified with simulation and experimental studies.","PeriodicalId":154402,"journal":{"name":"2013 IEEE Energytech","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123565221","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 : 2013-05-21DOI: 10.1109/ENERGYTECH.2013.6645299
Ran Wei, Peng Wang, W. Ko, P. Feng
We report on measurement and modeling of dynamic energy harvesters based on oscillating piezoelectric cantilevers, along with careful calibration of energy conversion properties of such devices in their dynamic responses. We employ thin-film lead zirconate titanate (PZT)-based cantilevers fabricated by laser micromachining, with efficient proof masses enabled by a heavy alloy with a low melting temperature (65°C) for tuning frequency and damping. By measuring devices with different circuit parameters, and analyzing the energy conversion in time-domain oscillations, we show a model that quantitatively reveals the effects of the loading circuit for energy harvesting. We also show the effects of device dimensions on their vibrations and converted voltage output waveforms. In harvesting vibrational energy through cycles of oscillations (in 80Hz-1kHz devices), energy conversion efficiency as high as 25% has been attained.
{"title":"Characterizing Piezoelectric Cantilevers for Vibration Energy Harvesting under Ambient Conditions","authors":"Ran Wei, Peng Wang, W. Ko, P. Feng","doi":"10.1109/ENERGYTECH.2013.6645299","DOIUrl":"https://doi.org/10.1109/ENERGYTECH.2013.6645299","url":null,"abstract":"We report on measurement and modeling of dynamic energy harvesters based on oscillating piezoelectric cantilevers, along with careful calibration of energy conversion properties of such devices in their dynamic responses. We employ thin-film lead zirconate titanate (PZT)-based cantilevers fabricated by laser micromachining, with efficient proof masses enabled by a heavy alloy with a low melting temperature (65°C) for tuning frequency and damping. By measuring devices with different circuit parameters, and analyzing the energy conversion in time-domain oscillations, we show a model that quantitatively reveals the effects of the loading circuit for energy harvesting. We also show the effects of device dimensions on their vibrations and converted voltage output waveforms. In harvesting vibrational energy through cycles of oscillations (in 80Hz-1kHz devices), energy conversion efficiency as high as 25% has been attained.","PeriodicalId":154402,"journal":{"name":"2013 IEEE Energytech","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117047493","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 : 2013-05-21DOI: 10.1109/ENERGYTECH.2013.6645339
S. Paul, M. A. Khan, Md. Rasheduzzaman Azad, R. K. Kundu
As the population is increasing of the world, the demand for the energy or power is also increasing. Enormous efforts and projects are being experimented for finding the right choice of energy source to use. Analyzing the recent condition of the power and energy sources we should depend on the alternative energy sources to meet the energy demand of the future generations. Solar, Wind, Biomass etc are the top choices as alternative energy source or renewable energy source. This paper aims to describe the performance analysis of the Mono-Crystal silicon solar Photovoltaic Module with booster reflector. An extended part of the experiment of an performance analysis study makes it clear that the performance of the MonoCrystal Silicon Solar PV module increases its power output by adding the booster reflector mirror.
{"title":"Performance studies of Mono-Crystal silicon solar Photovoltaic Module with booster reflector under Bangladeshi climatic condition","authors":"S. Paul, M. A. Khan, Md. Rasheduzzaman Azad, R. K. Kundu","doi":"10.1109/ENERGYTECH.2013.6645339","DOIUrl":"https://doi.org/10.1109/ENERGYTECH.2013.6645339","url":null,"abstract":"As the population is increasing of the world, the demand for the energy or power is also increasing. Enormous efforts and projects are being experimented for finding the right choice of energy source to use. Analyzing the recent condition of the power and energy sources we should depend on the alternative energy sources to meet the energy demand of the future generations. Solar, Wind, Biomass etc are the top choices as alternative energy source or renewable energy source. This paper aims to describe the performance analysis of the Mono-Crystal silicon solar Photovoltaic Module with booster reflector. An extended part of the experiment of an performance analysis study makes it clear that the performance of the MonoCrystal Silicon Solar PV module increases its power output by adding the booster reflector mirror.","PeriodicalId":154402,"journal":{"name":"2013 IEEE Energytech","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125267296","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 : 2013-05-21DOI: 10.1109/ENERGYTECH.2013.6645287
A. U. Lawan, N. Magaji, H. Musa
This paper investigates three polynomial strategies in damping oscillations in a horizontal axis turbine plant power systems, to demonstrate the influence of the introduction of the STATCOM in the power system, a comparative study is implemented using various polynomial algorithm control approaches to a horizontal wind axis turbine power system incooperating a static synchronous compensator (STATCOM). The proposed controllers' designs are based on a linear time invariant model of the plant and state feedback scheme. First, the linearized mathematical model of STATCOM is derived. Then, using polynomial algorithms as a state feedback algorithm, a state feedback control law is derived. The proposed control strategy is tested on SMIB power system with wind turbine by digital computer simulations using matlab/simulink and a power analysis toolbox. Comparison of the polynomial matching results of the controllers establishes the superb nature of polynomial approximation approach.
{"title":"A STATCOM controller for small signal stability using polynomial algorithms in a horizontal axis wind farm power system","authors":"A. U. Lawan, N. Magaji, H. Musa","doi":"10.1109/ENERGYTECH.2013.6645287","DOIUrl":"https://doi.org/10.1109/ENERGYTECH.2013.6645287","url":null,"abstract":"This paper investigates three polynomial strategies in damping oscillations in a horizontal axis turbine plant power systems, to demonstrate the influence of the introduction of the STATCOM in the power system, a comparative study is implemented using various polynomial algorithm control approaches to a horizontal wind axis turbine power system incooperating a static synchronous compensator (STATCOM). The proposed controllers' designs are based on a linear time invariant model of the plant and state feedback scheme. First, the linearized mathematical model of STATCOM is derived. Then, using polynomial algorithms as a state feedback algorithm, a state feedback control law is derived. The proposed control strategy is tested on SMIB power system with wind turbine by digital computer simulations using matlab/simulink and a power analysis toolbox. Comparison of the polynomial matching results of the controllers establishes the superb nature of polynomial approximation approach.","PeriodicalId":154402,"journal":{"name":"2013 IEEE Energytech","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124712660","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 : 2013-05-21DOI: 10.1109/ENERGYTECH.2013.6645331
Mohammed E. Eltayeb, H. Bahrami, T. Al-Naffouri
A key task of smart meters is to securely report the power consumption of households and provide dynamic pricing to consumers. While transmission to all meters can be performed via a simple broadcast, several challenges are faced during the reporting process. Firstly, the communication network should be able to handle the large amount of load reports, and secondly, the privacy of the load report should be ensured. In this paper, we propose a novel compressive sensing based network design that 1) reduces the communication network transmission overhead, and 2) ensures the privacy of the load reports. Based on recent findings from [1] and [2], numerical results show that the proposed design significantly reduces the network transmission overhead and utilizes the fading channel to encrypt the load reports, thus making it almost impossible for an eavesdropper to decipher the load reports.
{"title":"On the efficiency and privacy of smart grids neighborhood area networks","authors":"Mohammed E. Eltayeb, H. Bahrami, T. Al-Naffouri","doi":"10.1109/ENERGYTECH.2013.6645331","DOIUrl":"https://doi.org/10.1109/ENERGYTECH.2013.6645331","url":null,"abstract":"A key task of smart meters is to securely report the power consumption of households and provide dynamic pricing to consumers. While transmission to all meters can be performed via a simple broadcast, several challenges are faced during the reporting process. Firstly, the communication network should be able to handle the large amount of load reports, and secondly, the privacy of the load report should be ensured. In this paper, we propose a novel compressive sensing based network design that 1) reduces the communication network transmission overhead, and 2) ensures the privacy of the load reports. Based on recent findings from [1] and [2], numerical results show that the proposed design significantly reduces the network transmission overhead and utilizes the fading channel to encrypt the load reports, thus making it almost impossible for an eavesdropper to decipher the load reports.","PeriodicalId":154402,"journal":{"name":"2013 IEEE Energytech","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129592892","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 : 2013-05-21DOI: 10.1109/ENERGYTECH.2013.6645300
P. Parikh, YiFeng Wu, Likun Shen
With power conversion losses endemic in all areas of electricity consumption, broadly categorized into motion control (accounting for around 50% of total electrical energy use), lighting, air conditioning, and information technology, consumers, governments and utilities are finding ways to achieve higher efficiency. Manufacturers of data servers, telecom systems, solar power inverters and drives for motor control are focused on reducing power conversion losses while simultaneously shrinking the size of power systems. Although silicon has historically been the base device material used by the power conversion industry, it is rapidly reaching its physical performance limits. GaN semiconductors solutions reduce power conversion loss by over 50% in a significantly smaller form factor and at a lower cost, when device design, fabrication technology and application design are holistically combined to deliver superior end products.
{"title":"Commercialization of high 600V GaN-on-silicon power HEMTs and diodes","authors":"P. Parikh, YiFeng Wu, Likun Shen","doi":"10.1109/ENERGYTECH.2013.6645300","DOIUrl":"https://doi.org/10.1109/ENERGYTECH.2013.6645300","url":null,"abstract":"With power conversion losses endemic in all areas of electricity consumption, broadly categorized into motion control (accounting for around 50% of total electrical energy use), lighting, air conditioning, and information technology, consumers, governments and utilities are finding ways to achieve higher efficiency. Manufacturers of data servers, telecom systems, solar power inverters and drives for motor control are focused on reducing power conversion losses while simultaneously shrinking the size of power systems. Although silicon has historically been the base device material used by the power conversion industry, it is rapidly reaching its physical performance limits. GaN semiconductors solutions reduce power conversion loss by over 50% in a significantly smaller form factor and at a lower cost, when device design, fabrication technology and application design are holistically combined to deliver superior end products.","PeriodicalId":154402,"journal":{"name":"2013 IEEE Energytech","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114952861","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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