Pub Date : 2014-12-01DOI: 10.1109/ICECE.2014.7026915
D. Datta, M. Sheikh
Due to the recent expansion of renewable energy applications, wind energy conversion is receiving much interest all over the world. This is in no small part due to the rapid advances in the size of wind generators as well as the development of power electronics and their applicability in wind energy extraction, however, it has a great effect on the stability on power system. As wind turbine output is proportional to the cube of wind speed, the wind turbine generator output fluctuates due to wind speed variation. Thus this paper presents a new method to control the voltage stability by using reactive power compensation. It is observed that wind farm output voltage as well as grid voltage fluctuations can be controlled easily by applying this simple technique. Besides this, output voltage fluctuations can be smoothed by effectively controlling the reference voltage of the exciter of synchronous generator (SG). IEEE AC1A exciter is used in this study. Real wind speed data have been considered to obtained realistic responses. PSCAD/EMTDC software is used for simulation analyses.
{"title":"Voltage stability augmentation of ig based wind farm using capacitor with exciter control system","authors":"D. Datta, M. Sheikh","doi":"10.1109/ICECE.2014.7026915","DOIUrl":"https://doi.org/10.1109/ICECE.2014.7026915","url":null,"abstract":"Due to the recent expansion of renewable energy applications, wind energy conversion is receiving much interest all over the world. This is in no small part due to the rapid advances in the size of wind generators as well as the development of power electronics and their applicability in wind energy extraction, however, it has a great effect on the stability on power system. As wind turbine output is proportional to the cube of wind speed, the wind turbine generator output fluctuates due to wind speed variation. Thus this paper presents a new method to control the voltage stability by using reactive power compensation. It is observed that wind farm output voltage as well as grid voltage fluctuations can be controlled easily by applying this simple technique. Besides this, output voltage fluctuations can be smoothed by effectively controlling the reference voltage of the exciter of synchronous generator (SG). IEEE AC1A exciter is used in this study. Real wind speed data have been considered to obtained realistic responses. PSCAD/EMTDC software is used for simulation analyses.","PeriodicalId":335492,"journal":{"name":"8th International Conference on Electrical and Computer Engineering","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126086975","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 : 2014-12-01DOI: 10.1109/ICECE.2014.7026927
A. Ferdoush, M. G. Rabbani
Stability phenomena of the power system are largely studied by the researchers over the last few decades. In order to ensure a stable power system, power system stabilizer (PSS) is adopted which can increase the stability margin by providing supplementary feedback signal. For an efficient stabilization, the proper tuning of PSS parameters is very important. Now a days, the tuning appears a big challenge as the changes in power requirement take place continually. This paper deals with the tuning process of PSS connected to the single machine infinite bus (SMIB) system. The tuning method is decided based on the transfer function from SMIB model and the system frequency response. Simulation results are presented with and without PSS to demonstrate the effectiveness of proposed tuning method.
{"title":"Power system stabilizer tuning based on frequency response method","authors":"A. Ferdoush, M. G. Rabbani","doi":"10.1109/ICECE.2014.7026927","DOIUrl":"https://doi.org/10.1109/ICECE.2014.7026927","url":null,"abstract":"Stability phenomena of the power system are largely studied by the researchers over the last few decades. In order to ensure a stable power system, power system stabilizer (PSS) is adopted which can increase the stability margin by providing supplementary feedback signal. For an efficient stabilization, the proper tuning of PSS parameters is very important. Now a days, the tuning appears a big challenge as the changes in power requirement take place continually. This paper deals with the tuning process of PSS connected to the single machine infinite bus (SMIB) system. The tuning method is decided based on the transfer function from SMIB model and the system frequency response. Simulation results are presented with and without PSS to demonstrate the effectiveness of proposed tuning method.","PeriodicalId":335492,"journal":{"name":"8th International Conference on Electrical and Computer Engineering","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123783149","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 : 2014-12-01DOI: 10.1109/ICECE.2014.7026918
Rahat Yasir, M. A. Rahman, Nova Ahmed
Skin diseases are among the most common health problems worldwide. In this article we proposed a method that uses computer vision based techniques to detect various kinds of dermatological skin diseases. We have used different types of image processing algorithms for feature extraction and feed forward artificial neural network for training and testing purpose. The system works on two phases- first pre-process the colour skin images to extract significant features and later identifies the diseases. The system successfully detects 9 different types of dermatological skin diseases with an accuracy rate of 90%.
{"title":"Dermatological disease detection using image processing and artificial neural network","authors":"Rahat Yasir, M. A. Rahman, Nova Ahmed","doi":"10.1109/ICECE.2014.7026918","DOIUrl":"https://doi.org/10.1109/ICECE.2014.7026918","url":null,"abstract":"Skin diseases are among the most common health problems worldwide. In this article we proposed a method that uses computer vision based techniques to detect various kinds of dermatological skin diseases. We have used different types of image processing algorithms for feature extraction and feed forward artificial neural network for training and testing purpose. The system works on two phases- first pre-process the colour skin images to extract significant features and later identifies the diseases. The system successfully detects 9 different types of dermatological skin diseases with an accuracy rate of 90%.","PeriodicalId":335492,"journal":{"name":"8th International Conference on Electrical and Computer Engineering","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124783264","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 : 2014-12-01DOI: 10.1109/ICECE.2014.7026873
Md. Raju Ahmed, Utpal Kumar Das
Accidents caused by natural phenomena such as lightning are serious problems for the diffusions of wind power generations. To exploit high wind conditions, wind turbine generators are often constructed along the seashore where few tall structures exist; therefore, they are often struck by lightning. Most of the breakdowns and malfunctions of the electrical and control systems inside wind turbine due to lightning are caused by the voltage rise of the grounding system. At a disposal site like seashore where the resistivity of soil is very low, the voltage rise at grounding at the wave front typically becomes larger than that of the steady state because of the inductive behaviour of the grounding system. Voltage rise at grounding of wind turbine due to lightning at a disposal site are computed using electromagnetic analysis approach, and designing of proper grounding system at low resistivity soil is discussed. Finite Difference Time Domain (FDTD) method is used for electromagnetic analysis. Designing of grounding system of wind turbine at a disposal site is discussed.
{"title":"Lightning surge response of wind turbine grounding at low resistivity soil","authors":"Md. Raju Ahmed, Utpal Kumar Das","doi":"10.1109/ICECE.2014.7026873","DOIUrl":"https://doi.org/10.1109/ICECE.2014.7026873","url":null,"abstract":"Accidents caused by natural phenomena such as lightning are serious problems for the diffusions of wind power generations. To exploit high wind conditions, wind turbine generators are often constructed along the seashore where few tall structures exist; therefore, they are often struck by lightning. Most of the breakdowns and malfunctions of the electrical and control systems inside wind turbine due to lightning are caused by the voltage rise of the grounding system. At a disposal site like seashore where the resistivity of soil is very low, the voltage rise at grounding at the wave front typically becomes larger than that of the steady state because of the inductive behaviour of the grounding system. Voltage rise at grounding of wind turbine due to lightning at a disposal site are computed using electromagnetic analysis approach, and designing of proper grounding system at low resistivity soil is discussed. Finite Difference Time Domain (FDTD) method is used for electromagnetic analysis. Designing of grounding system of wind turbine at a disposal site is discussed.","PeriodicalId":335492,"journal":{"name":"8th International Conference on Electrical and Computer Engineering","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125985491","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 : 2014-12-01DOI: 10.1109/ICECE.2014.7026840
Md. Rifat Alam Siddique, M. Ferdous, I. Islam
A switched capacitor based step up converter with high voltage gain is proposed in this paper. The proposed novel topology of the boost converter can provide almost threefold output voltage relative to its input at 50% duty cycle. In order to guarantee small switching losses and to eliminate the current spikes problem across the switches (which usually exists in classical converter), an inductor is used in the circuit which creates a resonant tank and assist in zero current switching (ZCS). In addition, the efficiency curve of the new converter circuit shows high value for a wide range of output power which is rare in literature. Besides, this proposed topology is free from the circuitry design complexity. In renewable energy systems like photovoltaic panels or fuel cells, where a high step up voltage is required, the proposed converter can bear its suitability.
{"title":"Switched capacitor based soft-switching DC-DC boost converter for high voltage gain","authors":"Md. Rifat Alam Siddique, M. Ferdous, I. Islam","doi":"10.1109/ICECE.2014.7026840","DOIUrl":"https://doi.org/10.1109/ICECE.2014.7026840","url":null,"abstract":"A switched capacitor based step up converter with high voltage gain is proposed in this paper. The proposed novel topology of the boost converter can provide almost threefold output voltage relative to its input at 50% duty cycle. In order to guarantee small switching losses and to eliminate the current spikes problem across the switches (which usually exists in classical converter), an inductor is used in the circuit which creates a resonant tank and assist in zero current switching (ZCS). In addition, the efficiency curve of the new converter circuit shows high value for a wide range of output power which is rare in literature. Besides, this proposed topology is free from the circuitry design complexity. In renewable energy systems like photovoltaic panels or fuel cells, where a high step up voltage is required, the proposed converter can bear its suitability.","PeriodicalId":335492,"journal":{"name":"8th International Conference on Electrical and Computer Engineering","volume":"418 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124192010","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 : 2014-12-01DOI: 10.1109/ICECE.2014.7027015
M. I. Hossain, Rumana Binte Faruque, A. Chowdhury
Determination of the reliability of a substation is important as it helps locate weak points that may be contributing to overall power system unreliability. This paper evaluates reliability of 230 kV grid substations in Bangladesh subject to protection failures. The problem belongs to the dynamic reliability evaluation field. Event tree analysis is used as the main method. Fault tree analysis is used to get the input of the event tree. Reliability of five grid substations are calculated. Ishurdi grid substation is found to have a mean time to failure of only six months, which will affect seriously the design and safety of the proposed nuclear power station at Rooppur sited closely nearby.
{"title":"Reliability evaluation of grid substations in Bangladesh power system","authors":"M. I. Hossain, Rumana Binte Faruque, A. Chowdhury","doi":"10.1109/ICECE.2014.7027015","DOIUrl":"https://doi.org/10.1109/ICECE.2014.7027015","url":null,"abstract":"Determination of the reliability of a substation is important as it helps locate weak points that may be contributing to overall power system unreliability. This paper evaluates reliability of 230 kV grid substations in Bangladesh subject to protection failures. The problem belongs to the dynamic reliability evaluation field. Event tree analysis is used as the main method. Fault tree analysis is used to get the input of the event tree. Reliability of five grid substations are calculated. Ishurdi grid substation is found to have a mean time to failure of only six months, which will affect seriously the design and safety of the proposed nuclear power station at Rooppur sited closely nearby.","PeriodicalId":335492,"journal":{"name":"8th International Conference on Electrical and Computer Engineering","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130074750","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 : 2014-12-01DOI: 10.1109/ICECE.2014.7026848
G. M. M. Bashir, Samrat Kumar Dey, S. M. Tariq, Md. Shariful Islam
Distributing equivalent programming problems among the students for evaluation is an inherent problem. To remove this inherent problem, weight measurement of computer programs is necessary. Although software is the outcome of human creative activity, cognitive informatics plays an important role in understanding its fundamental characteristics. In our research, a new software complexity measure based on cognitive weight of basic control structure has been proposed that reduce the limitations of existing measures. Primarily our aim is to build a question bank with programming problems. Our designed system will access the solution codes for finding out the weight of respective programming problem from the question bank by applying the proposed method. The method will find out the complexity according to our proposed cognitive weight model. It will facilitate the instructors distributing the programming problems among the students equivalently. Thus, the automatic complexity measurement will ensure the students obtaining equal problems for programming evaluation.
{"title":"Complexity measurement: A new approach to ensure equal distribution of programming problems for evaluation","authors":"G. M. M. Bashir, Samrat Kumar Dey, S. M. Tariq, Md. Shariful Islam","doi":"10.1109/ICECE.2014.7026848","DOIUrl":"https://doi.org/10.1109/ICECE.2014.7026848","url":null,"abstract":"Distributing equivalent programming problems among the students for evaluation is an inherent problem. To remove this inherent problem, weight measurement of computer programs is necessary. Although software is the outcome of human creative activity, cognitive informatics plays an important role in understanding its fundamental characteristics. In our research, a new software complexity measure based on cognitive weight of basic control structure has been proposed that reduce the limitations of existing measures. Primarily our aim is to build a question bank with programming problems. Our designed system will access the solution codes for finding out the weight of respective programming problem from the question bank by applying the proposed method. The method will find out the complexity according to our proposed cognitive weight model. It will facilitate the instructors distributing the programming problems among the students equivalently. Thus, the automatic complexity measurement will ensure the students obtaining equal problems for programming evaluation.","PeriodicalId":335492,"journal":{"name":"8th International Conference on Electrical and Computer Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130502104","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 : 2014-12-01DOI: 10.1109/ICECE.2014.7026889
Md Zobaarul Haque, M. T. Islam, M. Uddin
In this paper, the optimal scheduling problem is studied in multi-user MIMO (MU-MIMO) single-hop uplink cellular networks. An optimization framework is developed to compute the optimal max-min throughput and the optimal scheduling of the users. The optimization problem is found to be a very complex linear program. The optimization problem is solved for several medium size cellular networks using an optimization tool. The numerical results show that MU-MIMO technique provides a significant throughput gain over SU-MIMO technique. To avoid the complexity of computation and implementation, a user grouping based simple scheduling algorithm is also proposed for MU-MIMO cellular networks. The performance of the proposed algorithm is evaluated and found to be very efficient.
{"title":"Optimal scheduling in MU-MIMO uplink cellular networks","authors":"Md Zobaarul Haque, M. T. Islam, M. Uddin","doi":"10.1109/ICECE.2014.7026889","DOIUrl":"https://doi.org/10.1109/ICECE.2014.7026889","url":null,"abstract":"In this paper, the optimal scheduling problem is studied in multi-user MIMO (MU-MIMO) single-hop uplink cellular networks. An optimization framework is developed to compute the optimal max-min throughput and the optimal scheduling of the users. The optimization problem is found to be a very complex linear program. The optimization problem is solved for several medium size cellular networks using an optimization tool. The numerical results show that MU-MIMO technique provides a significant throughput gain over SU-MIMO technique. To avoid the complexity of computation and implementation, a user grouping based simple scheduling algorithm is also proposed for MU-MIMO cellular networks. The performance of the proposed algorithm is evaluated and found to be very efficient.","PeriodicalId":335492,"journal":{"name":"8th International Conference on Electrical and Computer Engineering","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126447072","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 : 2014-12-01DOI: 10.1109/ICECE.2014.7026996
Shuvankar Podder, Raihan Sayeed Khan, Shah Md. Ashraful Alam Mohon, Md Jubair Hussain, E. Basher
Solar radiation at Patenga, Chittagong is predicted by using record of bright sunshine hours of that place. Monthly average solar radiation is calculated from Angstrom-Prescott equation. The coefficients of that equation is found as a = 0.1688 and b= 0.5869. Patenga is a coastal area of Bangladesh and has promising potential of hybrid solar-wind based electricity. Solar radiation data is required for planning and designing photovoltaic power plant. But Bangladesh Meteorological Department has no record of radiation data of that place. So, attempt has been made to estimate solar radiation from other available meteorological parameters. Accuracy of estimated radiation is determined by comparing with data obtained from NASA Surface Meteorology and Solar Energy (SSE). Also estimated radiation is compared with five widely accepted models used for calculating solar radiation. These models were developed considering wide range of geographical area so can be applicable for present location. Present model provide better error correction scheme compared to other considered models by generating more accurate coefficient for that place.
{"title":"Solar radiation approximation using sunshine hour at Patenga, Bangladesh","authors":"Shuvankar Podder, Raihan Sayeed Khan, Shah Md. Ashraful Alam Mohon, Md Jubair Hussain, E. Basher","doi":"10.1109/ICECE.2014.7026996","DOIUrl":"https://doi.org/10.1109/ICECE.2014.7026996","url":null,"abstract":"Solar radiation at Patenga, Chittagong is predicted by using record of bright sunshine hours of that place. Monthly average solar radiation is calculated from Angstrom-Prescott equation. The coefficients of that equation is found as a = 0.1688 and b= 0.5869. Patenga is a coastal area of Bangladesh and has promising potential of hybrid solar-wind based electricity. Solar radiation data is required for planning and designing photovoltaic power plant. But Bangladesh Meteorological Department has no record of radiation data of that place. So, attempt has been made to estimate solar radiation from other available meteorological parameters. Accuracy of estimated radiation is determined by comparing with data obtained from NASA Surface Meteorology and Solar Energy (SSE). Also estimated radiation is compared with five widely accepted models used for calculating solar radiation. These models were developed considering wide range of geographical area so can be applicable for present location. Present model provide better error correction scheme compared to other considered models by generating more accurate coefficient for that place.","PeriodicalId":335492,"journal":{"name":"8th International Conference on Electrical and Computer Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129010150","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 : 2014-12-01DOI: 10.1109/ICECE.2014.7026997
Abul Hasan Fahad, P. P. Dutta, A. Chowdhury
Electric arc furnaces (EAF) are very large electrical loads and they cause voltage flicker problem in the power system due to their non-linear and random electrical characteristics. Voltage flicker (cyclic and stochastic) causes annoying sensation experienced by human eye and is a very important power quality parameter. In this paper, a Matlab-Simulink based flicker severity analysis module has been proposed to analyse voltage flicker in the network under multiple EAF operation fed from a substation. In this module a new system-modelling strategy is proposed. The power system is modelled and simulated in Simulink and instantaneous voltage data is analysed by a separate Matlab program. With this module, a power system containing two parallel EAFs is modelled and simulated and the short-term flicker severity index of voltage at point of common coupling is calculated. This new module can be used very effectively to estimate the flicker of any system having multiple arc furnaces that are fed from a substation.
{"title":"A voltage flicker severity analysis module for multiple electric arc furnace operation","authors":"Abul Hasan Fahad, P. P. Dutta, A. Chowdhury","doi":"10.1109/ICECE.2014.7026997","DOIUrl":"https://doi.org/10.1109/ICECE.2014.7026997","url":null,"abstract":"Electric arc furnaces (EAF) are very large electrical loads and they cause voltage flicker problem in the power system due to their non-linear and random electrical characteristics. Voltage flicker (cyclic and stochastic) causes annoying sensation experienced by human eye and is a very important power quality parameter. In this paper, a Matlab-Simulink based flicker severity analysis module has been proposed to analyse voltage flicker in the network under multiple EAF operation fed from a substation. In this module a new system-modelling strategy is proposed. The power system is modelled and simulated in Simulink and instantaneous voltage data is analysed by a separate Matlab program. With this module, a power system containing two parallel EAFs is modelled and simulated and the short-term flicker severity index of voltage at point of common coupling is calculated. This new module can be used very effectively to estimate the flicker of any system having multiple arc furnaces that are fed from a substation.","PeriodicalId":335492,"journal":{"name":"8th International Conference on Electrical and Computer Engineering","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123368954","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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