M. Liukkonen, E. Nikolskaya, J-F Selin, Y. Hiltunen
In wastewater treatment, the dewatering of sludge is one of the most important steps, because it affects largely in both the process economics and the costs of sludge disposal. To optimize the dewatering processes, it would be beneficial to be aware of the different water types present in the sludge. In addition to free water, generally there are also mechanically, physically and chemically bound water within the sludge. All these water types behave differently when the sludge is dried, and they all require a different amount of energy when being removed. In this study, the Independent Component Analysis (ICA) method has been applied to an analysis of NMR (Nuclear Magnetic Resonance) relaxation data obtained from the measurement of wastewater sludge samples with a known moisture content. The results strongly suggest that the ICA method can be used for determining the amount of different water types within the wastewater sludge without a priori knowledge on their shares.
{"title":"Water Content Analysis of Sludge using NMR Relaxation Data and Independent Component Analysis","authors":"M. Liukkonen, E. Nikolskaya, J-F Selin, Y. Hiltunen","doi":"10.3384/ECP17142317","DOIUrl":"https://doi.org/10.3384/ECP17142317","url":null,"abstract":"In wastewater treatment, the dewatering of sludge is one of the most important steps, because it affects largely in both the process economics and the costs of sludge disposal. To optimize the dewatering processes, it would be beneficial to be aware of the different water types present in the sludge. In addition to free water, generally there are also mechanically, physically and chemically bound water within the sludge. All these water types behave differently when the sludge is dried, and they all require a different amount of energy when being removed. In this study, the Independent Component Analysis (ICA) method has been applied to an analysis of NMR (Nuclear Magnetic Resonance) relaxation data obtained from the measurement of wastewater sludge samples with a known moisture content. The results strongly suggest that the ICA method can be used for determining the amount of different water types within the wastewater sludge without a priori knowledge on their shares.","PeriodicalId":56990,"journal":{"name":"建模与仿真(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82050284","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}
Long Term Evolution (LTE) enables bandwidth consuming HTTP applications as video streaming. Mobile Network Operator (MNO) is committed to guarantee acceptable levels of Quality of Service (QoS) and Quality of Experience (QoE) perceived by the end user. A correlation between the transport informations with the application informations is an important approach to be adopted by the MNO. This correlation is more useful if a second entity, as the Over The Top (OTT), cooperates for the content delivery process. In the scientific literature different mathematical models are used in order to correlate QoE to the QoS. This paper aims at analyse them in case of of HTTP based Web services as HTTP web browsing and HTTP video streaming. Different scenarios are simulated using OPNET simulation software tool. They can differ if the service is fully managed by the MNO (MNO-managed class) or if OTT cooperates with own content (OTTmanaged). This is the case of YouTube. Results are analysed through regression kmeans clustering techniques.
长期演进(LTE)使带宽消耗的HTTP应用程序成为视频流。移动网络营办商(MNO)致力保证最终用户可接受的服务质素(QoS)和体验质素(QoE)水平。运输信息与应用信息之间的关联是MNO采用的一种重要方法。如果第二个实体(如Over the Top (OTT))在内容交付过程中进行合作，则这种相关性会更有用。在科学文献中，为了将QoE与QoS关联起来，使用了不同的数学模型。本文以基于HTTP的Web服务为例，对HTTP网页浏览和HTTP视频流进行了分析。利用OPNET仿真软件工具对不同场景进行了仿真。如果服务完全由MNO管理(MNO管理类)，或者OTT与自己的内容合作(OTTmanaged)，它们可能会有所不同。这就是YouTube的例子。通过回归均值聚类技术对结果进行分析。
{"title":"Simulation of HTTP-based Services Over LTE for QoE Estimation","authors":"Alessandro Vizzarri, F. Davide","doi":"10.3384/ECP17142381","DOIUrl":"https://doi.org/10.3384/ECP17142381","url":null,"abstract":"Long Term Evolution (LTE) enables bandwidth consuming HTTP applications as video streaming. Mobile Network Operator (MNO) is committed to guarantee acceptable levels of Quality of Service (QoS) and Quality of Experience (QoE) perceived by the end user. A correlation between the transport informations with the application informations is an important approach to be adopted by the MNO. This correlation is more useful if a second entity, as the Over The Top (OTT), cooperates for the content delivery process. In the scientific literature different mathematical models are used in order to correlate QoE to the QoS. This paper aims at analyse them in case of of HTTP based Web services as HTTP web browsing and HTTP video streaming. Different scenarios are simulated using OPNET simulation software tool. They can differ if the service is fully managed by the MNO (MNO-managed class) or if OTT cooperates with own content (OTTmanaged). This is the case of YouTube. Results are analysed through regression kmeans clustering techniques.","PeriodicalId":56990,"journal":{"name":"建模与仿真(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84049558","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}
System architectures of embedded systems are undergoing major changes. Embedded systems are becoming cyberphysical systems (CPS) with open interfaces and resulting distributed control loops. This calls for new testing approaches that enable early evaluation of system and safety concepts, and support the evaluation of system designs before they are implemented. Simulation is a common technology that supports the testing of embedded systems, but existing simulators are focused and specialized. A single simulator often does not support all models needed to provide a valid testing environment for system designs. In this paper, we describe our framework for the coupling of communication simulators to enable virtual testing and safeguarding of embedded system designs. The integration of network simulation models and fault injectors enables testing of safety concepts. The applicability of our approach is illustrated in the context of a case study based on a vehicle system design realized as contract work.
{"title":"Simulator Coupling for Network Fault Injection Testing","authors":"Emilia Cioroaica, T. Kuhn","doi":"10.3384/ECP17142742","DOIUrl":"https://doi.org/10.3384/ECP17142742","url":null,"abstract":"System architectures of embedded systems are undergoing major changes. Embedded systems are becoming cyberphysical systems (CPS) with open interfaces and resulting distributed control loops. This calls for new testing approaches that enable early evaluation of system and safety concepts, and support the evaluation of system designs before they are implemented. Simulation is a common technology that supports the testing of embedded systems, but existing simulators are focused and specialized. A single simulator often does not support all models needed to provide a valid testing environment for system designs. In this paper, we describe our framework for the coupling of communication simulators to enable virtual testing and safeguarding of embedded system designs. The integration of network simulation models and fault injectors enables testing of safety concepts. The applicability of our approach is illustrated in the context of a case study based on a vehicle system design realized as contract work.","PeriodicalId":56990,"journal":{"name":"建模与仿真(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81437099","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}
We consider a problem of trajectory planning for path with piecewise linear boundaries. The trajectory is constructed as smoothing splines using normalized uniform B-splines as the basis functions. The boundary constraints are treated as a collection of inequality pairs by right and left boundary lines, and are formulated as linear inequality constraints on the so-called control point vector. Smoothing splines are constructed as an approximation of a piecewise linear centerline of the given path, where the given entire time interval is divided into subintervals according to the centripetal distribution rule. Other constraints as initial and terminal conditions on the trajectory can be included easily, and the problem reduces to convex quadratic programming problem where very efficient numerical solvers are available. The effectiveness of the proposed method is confirmed by an example of fairly complex path with piecewise linear boundaries. Also an example is included to demonstrate its usefulness for trajectory planning in an environment with obstacles.
{"title":"Spline Trajectory Planning for Path with Piecewise Linear Boundaries","authors":"H. Kano, H. Fujioka","doi":"10.3384/ECP17142439","DOIUrl":"https://doi.org/10.3384/ECP17142439","url":null,"abstract":"We consider a problem of trajectory planning for path with piecewise linear boundaries. The trajectory is constructed as smoothing splines using normalized uniform B-splines as the basis functions. The boundary constraints are treated as a collection of inequality pairs by right and left boundary lines, and are formulated as linear inequality constraints on the so-called control point vector. Smoothing splines are constructed as an approximation of a piecewise linear centerline of the given path, where the given entire time interval is divided into subintervals according to the centripetal distribution rule. Other constraints as initial and terminal conditions on the trajectory can be included easily, and the problem reduces to convex quadratic programming problem where very efficient numerical solvers are available. The effectiveness of the proposed method is confirmed by an example of fairly complex path with piecewise linear boundaries. Also an example is included to demonstrate its usefulness for trajectory planning in an environment with obstacles.","PeriodicalId":56990,"journal":{"name":"建模与仿真(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78775902","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}
This paper presents a combustion model and a simulation method for modeling flame acceleration (FA) and deflagration to detonation transition (DDT) in a premixed gas. The method is intended to produce the most important effects in FA and DDT without resolving the flame front on the computational mesh. The simulations presented here are of stoichiometric hydrogen-air mixtures in a channel with repeated obstacles. The channel is 2 m long and 110 mm wide, with a height of either 20 mm or 40 mm. The obstacles gives a blockage ratio of 0.5. These values are the same as for experiments by other researchers and is used for comparison. The combustion model combines a turbulent burning velocity model and a two-step Arrhenius kinetic rate. The simulations show similar flame speeds and pressures as seen in experiments, and the process of DDT is shown to be caused by shock focusing and shock flame interactions. The simulations show that the quasi detonation regime is a series of transition to detonation events followed by failure of the detonation. Results from both 2D and 3D simulations are presented, since the 2D simulations show how the method can reproduce important effects.
{"title":"Simulation of Flame Acceleration and DDT","authors":"K. Vaagsaether","doi":"10.3384/ECP17142646","DOIUrl":"https://doi.org/10.3384/ECP17142646","url":null,"abstract":"This paper presents a combustion model and a simulation method for modeling flame acceleration (FA) and deflagration to detonation transition (DDT) in a premixed gas. The method is intended to produce the most important effects in FA and DDT without resolving the flame front on the computational mesh. The simulations presented here are of stoichiometric hydrogen-air mixtures in a channel with repeated obstacles. The channel is 2 m long and 110 mm wide, with a height of either 20 mm or 40 mm. The obstacles gives a blockage ratio of 0.5. These values are the same as for experiments by other researchers and is used for comparison. The combustion model combines a turbulent burning velocity model and a two-step Arrhenius kinetic rate. The simulations show similar flame speeds and pressures as seen in experiments, and the process of DDT is shown to be caused by shock focusing and shock flame interactions. The simulations show that the quasi detonation regime is a series of transition to detonation events followed by failure of the detonation. Results from both 2D and 3D simulations are presented, since the 2D simulations show how the method can reproduce important effects.","PeriodicalId":56990,"journal":{"name":"建模与仿真(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87609751","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 study, a variogram method was utilized as a variable selection tool for finding the optimal subsets of variables for developing predictive models for the quality of wastewater treatment effluent. The quality of effluent was here assessed by biological and chemical oxygen demand and suspended solids in biologically treated wastewater. The dataset included, in addition to traditional process measurements, results of a novel optical monitoring device which was used for imaging an activated sludge process in-situ during a period of over one year. The study showed that the variogram based method has potential in fast and computationally easy variable selection. The developed models can be used for proactive monitoring and estimating the quality of effluent in several stages hours before in comparison to laboratory analysis taken from treated wastewater.
{"title":"A Variogram-Based Tool for Variable Selection in a Wastewater Treatment Effluent Prediction","authors":"M. Ohenoja, J. Tomperi","doi":"10.3384/ECP17142312","DOIUrl":"https://doi.org/10.3384/ECP17142312","url":null,"abstract":"In this study, a variogram method was utilized as a variable selection tool for finding the optimal subsets of variables for developing predictive models for the quality of wastewater treatment effluent. The quality of effluent was here assessed by biological and chemical oxygen demand and suspended solids in biologically treated wastewater. The dataset included, in addition to traditional process measurements, results of a novel optical monitoring device which was used for imaging an activated sludge process in-situ during a period of over one year. The study showed that the variogram based method has potential in fast and computationally easy variable selection. The developed models can be used for proactive monitoring and estimating the quality of effluent in several stages hours before in comparison to laboratory analysis taken from treated wastewater.","PeriodicalId":56990,"journal":{"name":"建模与仿真(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88024379","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 the context of an industrial production of micro components, the planning and configuration of process chains constitutes a major factor of success for the involved companies. Besides very small tolerances and high quality requirements, high production speeds have to be achieved. Moreover, so called size-effects introduce additional uncertainties to the planning process. While the modelling methodology “Micro Process Planning and Analysis” provides a series of tools and methods to achieve a detailed planning and configuration of process chains in micro manufacturing, the high level of detail requires a comparably large amount of manual work, as well as a broad knowledge about available processes. Moreover, several processes can be substituted to achieve specific forms and shapes, while providing their own advantages and disadvantages for the overall production system. This article describes an extension to the methodology, which enables an automatic selection of suitable processes using geometry focused annotations. While these annotations only add minor efforts to the modelling process, they can be used to automatically derive alternative process chains. Particularly for production systems offering a broad range of processes, this extension reduces the manual effort in modelling and evaluating alternative process chains.
{"title":"Domain-Specific Modelling of Micro Manufacturing Processes for the Design of Alternative Process Chain","authors":"D. Rippel, M. Lütjen, M. Freitag","doi":"10.3384/ECP17142700","DOIUrl":"https://doi.org/10.3384/ECP17142700","url":null,"abstract":"In the context of an industrial production of micro components, the planning and configuration of process chains constitutes a major factor of success for the involved companies. Besides very small tolerances and high quality requirements, high production speeds have to be achieved. Moreover, so called size-effects introduce additional uncertainties to the planning process. While the modelling methodology “Micro Process Planning and Analysis” provides a series of tools and methods to achieve a detailed planning and configuration of process chains in micro manufacturing, the high level of detail requires a comparably large amount of manual work, as well as a broad knowledge about available processes. Moreover, several processes can be substituted to achieve specific forms and shapes, while providing their own advantages and disadvantages for the overall production system. This article describes an extension to the methodology, which enables an automatic selection of suitable processes using geometry focused annotations. While these annotations only add minor efforts to the modelling process, they can be used to automatically derive alternative process chains. Particularly for production systems offering a broad range of processes, this extension reduces the manual effort in modelling and evaluating alternative process chains.","PeriodicalId":56990,"journal":{"name":"建模与仿真(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88299939","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}
Mark Schillinger, Benedikt Ortelt, Benjamin Hartmann, J. Schreiter, Mona Meister, D. Nguyen-Tuong, O. Nelles
When modeling technical systems as black-box models, it is crucial to obtain as much and as informative measurement data as possible in the shortest time while employing safety constraints. Methods for an optimized online generation of measurement data are discussed in the field of Active Learning. Safe Active Learning combines the optimization of the query strategy regarding model quality with an exploration scheme in order to maintain userdefined safety constraints. In this paper, the authors apply an approach for Safe Active Learning based on Gaussian process models (GP models) to the high pressure fuel supply system of a gasoline engine. For this purpose, several enhancements of the algorithm are necessary. An online optimization of the GP models’ hyperparameters is implemented, where special measures are taken to avoid a safety-relevant overestimation. A proper risk function is chosen and the trajectory to the sample points is taken into account regarding the estimation of the samples feasibility. The algorithm is evaluated in simulation and at a test vehicle.
{"title":"Safe Active Learning of a High Pressure Fuel Supply System","authors":"Mark Schillinger, Benedikt Ortelt, Benjamin Hartmann, J. Schreiter, Mona Meister, D. Nguyen-Tuong, O. Nelles","doi":"10.3384/ECP17142286","DOIUrl":"https://doi.org/10.3384/ECP17142286","url":null,"abstract":"When modeling technical systems as black-box models, it is crucial to obtain as much and as informative measurement data as possible in the shortest time while employing safety constraints. Methods for an optimized online generation of measurement data are discussed in the field of Active Learning. Safe Active Learning combines the optimization of the query strategy regarding model quality with an exploration scheme in order to maintain userdefined safety constraints. In this paper, the authors apply an approach for Safe Active Learning based on Gaussian process models (GP models) to the high pressure fuel supply system of a gasoline engine. For this purpose, several enhancements of the algorithm are necessary. An online optimization of the GP models’ hyperparameters is implemented, where special measures are taken to avoid a safety-relevant overestimation. A proper risk function is chosen and the trajectory to the sample points is taken into account regarding the estimation of the samples feasibility. The algorithm is evaluated in simulation and at a test vehicle.","PeriodicalId":56990,"journal":{"name":"建模与仿真(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75426975","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 rate of inflow to a horizontal well could vary along the completion length due frictional pressure losses or heterogeneity in the reservoir. These variations reduce oil sweep efficiency and the ultimate recovery. Owing to this, it is necessary to manage fluid flow through the reservoir in order to maximize oil recovery along horizontal wells. One increasingly popular approach is to use inflow control devices (ICD) that delay water and gas breakthrough into the well. Inflow control devices balance the inflow coming from the reservoir towards the wellbore by introducing an extra pressure drop. This paper presents the mathematical models used for the implementation of ICD in ECLIPSE. A case using heterogeneous reservoir similar to Troll offshore Norway was illustrated. The simulation result shows that ICD could delay water breakthrough for 262days and water cut after 3000days reduced by 11%. Gas breakgthrough was also reduced by approximately 51% with ICD.
{"title":"The Application of Inflow Control Device for an Improved Oil Recovery using ECLIPSE","authors":"A. Ugwu, Britt M. E. Moldestad","doi":"10.3384/ECP17142694","DOIUrl":"https://doi.org/10.3384/ECP17142694","url":null,"abstract":"The rate of inflow to a horizontal well could vary along the completion length due frictional pressure losses or heterogeneity in the reservoir. These variations reduce oil sweep efficiency and the ultimate recovery. Owing to this, it is necessary to manage fluid flow through the reservoir in order to maximize oil recovery along horizontal wells. One increasingly popular approach is to use inflow control devices (ICD) that delay water and gas breakthrough into the well. Inflow control devices balance the inflow coming from the reservoir towards the wellbore by introducing an extra pressure drop. This paper presents the mathematical models used for the implementation of ICD in ECLIPSE. A case using heterogeneous reservoir similar to Troll offshore Norway was illustrated. The simulation result shows that ICD could delay water breakthrough for 262days and water cut after 3000days reduced by 11%. Gas breakgthrough was also reduced by approximately 51% with ICD.","PeriodicalId":56990,"journal":{"name":"建模与仿真(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74799423","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 algorithm for coefficients determination for stability polynomials of degree up to m = 35 is developed. The coefficients correspond to explicit Runge-Kutta methods of the first accuracy order. Dependence between values of a polynomial at the points of extremum and both size and form of a stability domain is shown. Numerical results are given.
{"title":"Numerical Algorithm for Design of Stability Polynomials for the First Order Methods","authors":"E. Novikov, M. V. Rybkov, A. Novikov","doi":"10.3384/ECP17142979","DOIUrl":"https://doi.org/10.3384/ECP17142979","url":null,"abstract":"The algorithm for coefficients determination for stability polynomials of degree up to m = 35 is developed. The coefficients correspond to explicit Runge-Kutta methods of the first accuracy order. Dependence between values of a polynomial at the points of extremum and both size and form of a stability domain is shown. Numerical results are given.","PeriodicalId":56990,"journal":{"name":"建模与仿真(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74802073","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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