In this research a public dataset of recordings of EEG signals of healthy subjects and epileptic patients was used to build three simple classifiers with low time complexity, these are decision tree, random forest and AdaBoost algorithm. The data was initially preprocessed to extract short waves of electrical signals representing brain activity. The signals are then used for the selected models. Experimental results showed that random forest achieved the best accuracy of detection of the presence/absence of epileptic seizure in the EEG signals at 97.23% followed by decision tree with accuracy of 96.93%. The least performing algorithm was the AdaBoost scoring accuracy of 87.23%. Further, the AUC scores were 99% for decision tree, 99.9% for random forest and 95.6% for AdaBoost. These results are comparable to state-of-the-art classifiers which have higher time complexity.
{"title":"Detection of epileptic seizures in EEG by using machine learning techniques","authors":"Muayed S. Al-Huseiny, Ahmed S. Sajit","doi":"10.29354/diag/158277","DOIUrl":"https://doi.org/10.29354/diag/158277","url":null,"abstract":"In this research a public dataset of recordings of EEG signals of healthy subjects and epileptic patients was used to build three simple classifiers with low time complexity, these are decision tree, random forest and AdaBoost algorithm. The data was initially preprocessed to extract short waves of electrical signals representing brain activity. The signals are then used for the selected models. Experimental results showed that random forest achieved the best accuracy of detection of the presence/absence of epileptic seizure in the EEG signals at 97.23% followed by decision tree with accuracy of 96.93%. The least performing algorithm was the AdaBoost scoring accuracy of 87.23%. Further, the AUC scores were 99% for decision tree, 99.9% for random forest and 95.6% for AdaBoost. These results are comparable to state-of-the-art classifiers which have higher time complexity.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45942927","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}
Ayu Latifah, A. Ramelan, D. Lubis, B. Trilaksono, E. Hidayat
An autonomous underwater vehicle is a vehicle that can move in water, which is also known as an unmanned undersea vehicle. One type is the hybrid underwater glider where the vehicle is designed in such a way that it is able to carry out missions in the water with less power consumption so that it can last a long time in carrying out missions. In this research, a mathematical design is carried out in the form of a nonlinear model with the aim of being able to produce a model in the longitudinal movement of the HUG vehicle which will be tested limited to a simulation using the MATLAB/Simulink program. The parameters used in the model for this longitudinal movement are obtained by the computational fluid dynamics method so that it has been simulated with various movements according to the mission of the vehicle. In the simulation, input is given in the form of variations in the value of the actuator force to be able to carry out movements according to the mission and the simulation is open loop so that the vehicle's response is in the form of position and speed of
{"title":"Longitudinal movement modeling and simulation for hybrid underwater glider","authors":"Ayu Latifah, A. Ramelan, D. Lubis, B. Trilaksono, E. Hidayat","doi":"10.29354/diag/158074","DOIUrl":"https://doi.org/10.29354/diag/158074","url":null,"abstract":"An autonomous underwater vehicle is a vehicle that can move in water, which is also known as an unmanned undersea vehicle. One type is the hybrid underwater glider where the vehicle is designed in such a way that it is able to carry out missions in the water with less power consumption so that it can last a long time in carrying out missions. In this research, a mathematical design is carried out in the form of a nonlinear model with the aim of being able to produce a model in the longitudinal movement of the HUG vehicle which will be tested limited to a simulation using the MATLAB/Simulink program. The parameters used in the model for this longitudinal movement are obtained by the computational fluid dynamics method so that it has been simulated with various movements according to the mission of the vehicle. In the simulation, input is given in the form of variations in the value of the actuator force to be able to carry out movements according to the mission and the simulation is open loop so that the vehicle's response is in the form of position and speed of","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44784784","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}
In this article, the problem of the free vibration behavior of a cantilever Euler-Bernoulli beam with various non-classical boundary conditions, such as rotational, translational spring, and attached mass is investigated. For describing the differential equation of the system. An analytical procedure is proposed firstly, and a numerical method based on the differential transform method DTM is developed in order to validate the obtained results. A parametric study for various degenerate cases is presented with the aim to analyze the influence of rotational stiffness, vertical stiffness, and mass ratio on the free vibration response of the beam, particularly on its modal characteristics. The results show that the non-classical boundary conditions significantly affect the natural frequency and mode shapes of the studied beam system in comparison to the case of a classical boundary conditions such as Simply supported, clamped-clamped, etc. The comparison between the obtained results based on the proposed analytical solution and numerical scheme, and those available in the literature shows an excellent agreement.
{"title":"Effects of non-classical boundary conditions on the free vibration response of a cantilever Euler-Bernoulli beams","authors":"Abderrachid Afras, A. El Ghoulbzouri","doi":"10.29354/diag/158075","DOIUrl":"https://doi.org/10.29354/diag/158075","url":null,"abstract":"In this article, the problem of the free vibration behavior of a cantilever Euler-Bernoulli beam with various non-classical boundary conditions, such as rotational, translational spring, and attached mass is investigated. For describing the differential equation of the system. An analytical procedure is proposed firstly, and a numerical method based on the differential transform method DTM is developed in order to validate the obtained results. A parametric study for various degenerate cases is presented with the aim to analyze the influence of rotational stiffness, vertical stiffness, and mass ratio on the free vibration response of the beam, particularly on its modal characteristics. The results show that the non-classical boundary conditions significantly affect the natural frequency and mode shapes of the studied beam system in comparison to the case of a classical boundary conditions such as Simply supported, clamped-clamped, etc. The comparison between the obtained results based on the proposed analytical solution and numerical scheme, and those available in the literature shows an excellent agreement.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48516223","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}
V. Druzhinin, G. Sivyakova, A. Kalinin, V. Tytiuk, Anatolii Nikolenko, Vitaliy Kuznetsov, M. Kuzmenko
In recent years, due to the tightening of competition in the global market of steel producers, the requirements for the quality of hot-rolled steel have increased. The finishing group of the rolling mill is characterized by a complex structure of mechanical and electrical parts. The operation of electric drive systems of such units is characterized by the interrelation of electromagnetic processes, mechanical phenomena and technological factors. As experimental studies have shown, the quality of the supply voltage is inextricably linked with the impact nature of the loads in the rolling stands of the roughing and finishing groups of the hot rolling mill. A decrease in the supply voltage may be accompanied by the development of emergency modes of synchronous electric drives, leading to a decrease in the quality of the finished product.The paper developed a mathematical model of the power supply system of the rolling mill JSC "ArcelorMittal Temirtau". It is shown that this can lead to loss of synchronism of the synchronous motor. Such a voltage drop has a significant impact on the operation of DC electric drives of the finishing group. Various strategies are proposed to counter the development of emergency situations.
{"title":"Preventing the development of emergency modes of interlocked electric drives of a rolling mill under the impact loads","authors":"V. Druzhinin, G. Sivyakova, A. Kalinin, V. Tytiuk, Anatolii Nikolenko, Vitaliy Kuznetsov, M. Kuzmenko","doi":"10.29354/diag/157089","DOIUrl":"https://doi.org/10.29354/diag/157089","url":null,"abstract":"In recent years, due to the tightening of competition in the global market of steel producers, the requirements for the quality of hot-rolled steel have increased. The finishing group of the rolling mill is characterized by a complex structure of mechanical and electrical parts. The operation of electric drive systems of such units is characterized by the interrelation of electromagnetic processes, mechanical phenomena and technological factors. As experimental studies have shown, the quality of the supply voltage is inextricably linked with the impact nature of the loads in the rolling stands of the roughing and finishing groups of the hot rolling mill. A decrease in the supply voltage may be accompanied by the development of emergency modes of synchronous electric drives, leading to a decrease in the quality of the finished product.The paper developed a mathematical model of the power supply system of the rolling mill JSC \"ArcelorMittal Temirtau\". It is shown that this can lead to loss of synchronism of the synchronous motor. Such a voltage drop has a significant impact on the operation of DC electric drives of the finishing group. Various strategies are proposed to counter the development of emergency situations.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43258540","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}
Mechanically, composite laminates perform exceptionally well in-plane but poorly out-of-plane. Interlaminar damage, known as "delamination," is a major issue for composite laminates. Results from Mode-I and Mode-II experimental testing on twill-woven carbon fiber reinforced (CFRP) laminates are analyzed in this paper. Composite Mode-I fracture toughness was determined using three different methods in accordance with ASTM D5528: modified beam theory, compliance calibration, and a codified compliance calibration. Two methods, the Compliance Calibration Method and the Compliance-Based Beam Method, were used to determine the Mode-II fracture toughness in accordance with ASTM D7905. Stick-slip behavior is quite evident in the composite's Mode-I fracture toughness test findings. The MBT technique's 𝐺 Ic values for initiation and propagation are 0.533 and 0.679 KJ/m 2 , respectively. When comparing the MBT approach to the industry-standard ASTM procedure for determining fracture toughness Mode-I, the MBT method was shown to be highly compatible. Furthermore, the 𝐺 IIc values for the CBBM technique are 1.65 KJ/m 2 for non-pre cracked and 1.4 KJ/m 2 for pre-cracked materials. The CBBM method shows a good method to evaluate fracture toughness Mode-II, due to not needing to monitor the length of the crack during delamination growth to get the value of the fracture toughness.
{"title":"An experimental investigation of fracture modes and delamination behavior of carbon fiber reinforced laminated composite materials","authors":"Mustafa Musafir, Zuhair Ameer, A. Hamzah","doi":"10.29354/diag/156749","DOIUrl":"https://doi.org/10.29354/diag/156749","url":null,"abstract":"Mechanically, composite laminates perform exceptionally well in-plane but poorly out-of-plane. Interlaminar damage, known as \"delamination,\" is a major issue for composite laminates. Results from Mode-I and Mode-II experimental testing on twill-woven carbon fiber reinforced (CFRP) laminates are analyzed in this paper. Composite Mode-I fracture toughness was determined using three different methods in accordance with ASTM D5528: modified beam theory, compliance calibration, and a codified compliance calibration. Two methods, the Compliance Calibration Method and the Compliance-Based Beam Method, were used to determine the Mode-II fracture toughness in accordance with ASTM D7905. Stick-slip behavior is quite evident in the composite's Mode-I fracture toughness test findings. The MBT technique's 𝐺 Ic values for initiation and propagation are 0.533 and 0.679 KJ/m 2 , respectively. When comparing the MBT approach to the industry-standard ASTM procedure for determining fracture toughness Mode-I, the MBT method was shown to be highly compatible. Furthermore, the 𝐺 IIc values for the CBBM technique are 1.65 KJ/m 2 for non-pre cracked and 1.4 KJ/m 2 for pre-cracked materials. The CBBM method shows a good method to evaluate fracture toughness Mode-II, due to not needing to monitor the length of the crack during delamination growth to get the value of the fracture toughness.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42606005","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}
To initiate its combustion cycles, internal combustion engines require a minimum rotational speed that can be given from several sources (muscular, electrical, pneumatic, among others). Advantages of initiating an ICE with an AC electrical machine is that it can integrate starter motor and generator in one device, provide a linear ramp of acceleration when starting, and assist the ICE in torque production. This article illustrates considerations for the design of a starting system with an AC electrical machine. Initially, criteria of torque, rotational speed and power requirements are analysed, considering resistances of compression, friction, and inertia of the slider-crank mechanism, as well as accessories, with a preliminary experimental validation. Also, types of three-phase AC electrical machines are put to comparison, as well as their associated electronic components needed for driving them in each case, concluding that AC induction machines require a complex 4-quadrant inverter. PM synchronous machines require a simpler inverter, but with highly specified power electronics components. The classical wound rotor machine requires the simplest inverter, with unidirectional power flow, less power transfer losses and less critical power electronics components. Finally, considerations for using of a battery assisted with supercapacitor as complementary DC power source are made.
{"title":"Considerations for starting combustion engines with AC machines","authors":"M. Monroy, C. Romero, Edison Henao","doi":"10.29354/diag/156748","DOIUrl":"https://doi.org/10.29354/diag/156748","url":null,"abstract":"To initiate its combustion cycles, internal combustion engines require a minimum rotational speed that can be given from several sources (muscular, electrical, pneumatic, among others). Advantages of initiating an ICE with an AC electrical machine is that it can integrate starter motor and generator in one device, provide a linear ramp of acceleration when starting, and assist the ICE in torque production. This article illustrates considerations for the design of a starting system with an AC electrical machine. Initially, criteria of torque, rotational speed and power requirements are analysed, considering resistances of compression, friction, and inertia of the slider-crank mechanism, as well as accessories, with a preliminary experimental validation. Also, types of three-phase AC electrical machines are put to comparison, as well as their associated electronic components needed for driving them in each case, concluding that AC induction machines require a complex 4-quadrant inverter. PM synchronous machines require a simpler inverter, but with highly specified power electronics components. The classical wound rotor machine requires the simplest inverter, with unidirectional power flow, less power transfer losses and less critical power electronics components. Finally, considerations for using of a battery assisted with supercapacitor as complementary DC power source are made.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45644171","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}
The effect of adding zirconium (Zr) as an alloying element to Al-Cu-Mg alloy on the hardness and corrosion of this alloy was investigated. The hardness and polarization test results of samples treated for various periods by aging at 423.15 K for 3hr showed a significant increment in the Brinell hardness (HBW) improvement ratio of 115.6% (from 45HBW to 97HBW) and an extreme reduction the corrosion rate of the alloy after Zr adding decrease in the current density by 79.42% (from 56.50 µA cm-2 to 11.63 µA cm-2) with aging for 3 hr compared to the base alloy. The impact of this addition is also reflected in the strengthening, recrystallization, and modification of the grain microstructure. These changes were clearly demonstrated by microscopic testing and proves that the addition of Zr has a considerable synergistic effect causing inhibition of recrystallization and refinement of grain size.
{"title":"Hardness, corrosion behavior, and microstructure of Al-Cu-Mg alloy as a fuction of 0.3 wt.% Zr addition","authors":"K. Saad, J. Al-Murshdy","doi":"10.29354/diag/156750","DOIUrl":"https://doi.org/10.29354/diag/156750","url":null,"abstract":"The effect of adding zirconium (Zr) as an alloying element to Al-Cu-Mg alloy on the hardness and corrosion of this alloy was investigated. The hardness and polarization test results of samples treated for various periods by aging at 423.15 K for 3hr showed a significant increment in the Brinell hardness (HBW) improvement ratio of 115.6% (from 45HBW to 97HBW) and an extreme reduction the corrosion rate of the alloy after Zr adding decrease in the current density by 79.42% (from 56.50 µA cm-2 to 11.63 µA cm-2) with aging for 3 hr compared to the base alloy. The impact of this addition is also reflected in the strengthening, recrystallization, and modification of the grain microstructure. These changes were clearly demonstrated by microscopic testing and proves that the addition of Zr has a considerable synergistic effect causing inhibition of recrystallization and refinement of grain size.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47415207","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}
The transition from internal combustion to electric propulsion in cars presents component designers with new challenges in terms of noise reduction. Until now, components such as the suspension, its knocks were masked by the combustion engine or exhaust system. The absence of such significant sources, means that hitherto inaudible components are starting to become a nuisance. In order to reduce their noise, a number of optimisation solutions, both active and passive, are used. In order to do so, relevant measurements and data analysis must be carried out. This paper aims to present the acoustic characteristics of the interiors of two cars excited structurally in the vicinity of the front shock absorber mounting and by the operation of another component, the windscreen wipers on dry and wet windscreens. Measurements were made using 3D intensity probes based on acoustic particle velocity sensors. The results, in the form of both acoustic particle velocity and sound pressure characteristics and spectrograms, are presented comparatively for two types of car.
{"title":"Measurements of acoustic response of car interion for structural excitations","authors":"Wojciech Paluch, M. Kłaczyński","doi":"10.29354/diag/156893","DOIUrl":"https://doi.org/10.29354/diag/156893","url":null,"abstract":"The transition from internal combustion to electric propulsion in cars presents component designers with new challenges in terms of noise reduction. Until now, components such as the suspension, its knocks were masked by the combustion engine or exhaust system. The absence of such significant sources, means that hitherto inaudible components are starting to become a nuisance. In order to reduce their noise, a number of optimisation solutions, both active and passive, are used. In order to do so, relevant measurements and data analysis must be carried out. This paper aims to present the acoustic characteristics of the interiors of two cars excited structurally in the vicinity of the front shock absorber mounting and by the operation of another component, the windscreen wipers on dry and wet windscreens. Measurements were made using 3D intensity probes based on acoustic particle velocity sensors. The results, in the form of both acoustic particle velocity and sound pressure characteristics and spectrograms, are presented comparatively for two types of car.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42595093","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}
Summary Vehicle suspension system diagnostics is essential to both operation and maintenance of automotive vehicles. Diagnostic methods should provide signals that in-service defects have occurred as early as possible and make it possible to identify such defects in an unambiguous manner. Among the most popular oscillatory methods used to examine the technical condition of suspension systems, the EUSAMA method, developed by the European Shock Absorbers Manufacturers Association, has enjoyed particularly wide application, and it consists in establishing the ratio between the minimum value of the wheel adhesion force within the band of resonance of unsprung masses and the static wheel load value, expressed in per cent. Technical condition classification is based on comparing the values of what is commonly referred to as the EUSAMA coefficient (percentage ratio of a minimum wheel load force to a tangential vehicle wheel load on a test stand plate) for two wheels of a single axle. Such a test stand typically features only a load force sensor integrated with the test plate. The modification proposed by the authors involves installing an additional test plate displacement sensor at the test stand. When performed simultaneously, measurements of the load force affecting the plate and of its displacement make it possible to determine the phase angle between the relevant signals and to analyse the possibility of using the phase angle as an additional source of information about the technical condition of the vehicle suspension system.
{"title":"Analysis of the possibility of using the phase angle in the Eusama method as an additional diagnostic parameter in the assessment of the technical condition of the vehicle suspension system","authors":"Ł. Konieczny, J. Filipczyk","doi":"10.29354/diag/156917","DOIUrl":"https://doi.org/10.29354/diag/156917","url":null,"abstract":"Summary Vehicle suspension system diagnostics is essential to both operation and maintenance of automotive vehicles. Diagnostic methods should provide signals that in-service defects have occurred as early as possible and make it possible to identify such defects in an unambiguous manner. Among the most popular oscillatory methods used to examine the technical condition of suspension systems, the EUSAMA method, developed by the European Shock Absorbers Manufacturers Association, has enjoyed particularly wide application, and it consists in establishing the ratio between the minimum value of the wheel adhesion force within the band of resonance of unsprung masses and the static wheel load value, expressed in per cent. Technical condition classification is based on comparing the values of what is commonly referred to as the EUSAMA coefficient (percentage ratio of a minimum wheel load force to a tangential vehicle wheel load on a test stand plate) for two wheels of a single axle. Such a test stand typically features only a load force sensor integrated with the test plate. The modification proposed by the authors involves installing an additional test plate displacement sensor at the test stand. When performed simultaneously, measurements of the load force affecting the plate and of its displacement make it possible to determine the phase angle between the relevant signals and to analyse the possibility of using the phase angle as an additional source of information about the technical condition of the vehicle suspension system.","PeriodicalId":52164,"journal":{"name":"Diagnostyka","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44984220","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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