Pub Date : 2013-10-28DOI: 10.1109/ETFA.2013.6648009
Milton Armando Cunguara, T. E. O. Silva, P. Pedreiras
Over the last few years the problem of optimal estimation and control over lossy networks has been studied in detail. However, most of such works assume that in the absence of a new actuation value, the actuator either outputs zero or the previous value. Some other extensions have been proposed, but they present similar limitations. This paper shows that this method is not optimal and presents a new approach, in which the controller sends a number of predictions of future actuation values, which are outputted when the actuator does not receive a new message. Under this new assumption it is shown that the controller/estimator herein presented performs equal to or better than any previously introduced controller, being the equality verified only in the absence of communication errors. A modified Kalman filter as well as a specific optimal controller for this novel actuation model are also presented.
{"title":"On the application of block transmissions for improving control over lossy networks","authors":"Milton Armando Cunguara, T. E. O. Silva, P. Pedreiras","doi":"10.1109/ETFA.2013.6648009","DOIUrl":"https://doi.org/10.1109/ETFA.2013.6648009","url":null,"abstract":"Over the last few years the problem of optimal estimation and control over lossy networks has been studied in detail. However, most of such works assume that in the absence of a new actuation value, the actuator either outputs zero or the previous value. Some other extensions have been proposed, but they present similar limitations. This paper shows that this method is not optimal and presents a new approach, in which the controller sends a number of predictions of future actuation values, which are outputted when the actuator does not receive a new message. Under this new assumption it is shown that the controller/estimator herein presented performs equal to or better than any previously introduced controller, being the equality verified only in the absence of communication errors. A modified Kalman filter as well as a specific optimal controller for this novel actuation model are also presented.","PeriodicalId":106678,"journal":{"name":"2013 IEEE 18th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127735567","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 : 2013-10-28DOI: 10.1109/ETFA.2013.6648123
Pekka Aarnio, I. Seilonen
An approach to using RDF triple stores as a knowledge management technology for CBM services is presented in this paper. According to the approach, the management of the case knowledge handled in CBM services can be implemented with RDF triple store technology. The case knowledge in CBM services is descriptions of equipment diagnosis situation and their solutions. This paper presents the design of a case knowledge base management system (KBMS) build over the Virtuoso triple store. The approach has been evaluated with real industrial case data related to control valves. Initial results from the evaluation suggest the feasibility of the approach.
{"title":"RDF triple stores as a knowledge management technology for CBM services","authors":"Pekka Aarnio, I. Seilonen","doi":"10.1109/ETFA.2013.6648123","DOIUrl":"https://doi.org/10.1109/ETFA.2013.6648123","url":null,"abstract":"An approach to using RDF triple stores as a knowledge management technology for CBM services is presented in this paper. According to the approach, the management of the case knowledge handled in CBM services can be implemented with RDF triple store technology. The case knowledge in CBM services is descriptions of equipment diagnosis situation and their solutions. This paper presents the design of a case knowledge base management system (KBMS) build over the Virtuoso triple store. The approach has been evaluated with real industrial case data related to control valves. Initial results from the evaluation suggest the feasibility of the approach.","PeriodicalId":106678,"journal":{"name":"2013 IEEE 18th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121432486","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 : 2013-10-28DOI: 10.1109/ETFA.2013.6647986
Waqas Ikram, Niklas Jansson, T. Harvei, B. Fismen, J. Svare, N. Aakvaag, Stig Petersen, Simon Carlsen
Wireless communication is one of the fastest growing technologies in process automation and now targets main stream applications. One such application is a safety application; it is unique in its own rights, as any problem with safety related equipment, network or system can compromise on-site safety. For the wired networks which serve safety applications, they are designed to ensure QoS. Therefore, controlling delay, jitter, packet loss rate and bandwidth is critical. To achieve the same performance over an envisioned wireless network with shared communication medium, various problems are to be dealt with. In this regard, this paper is an effort towards the design of a SIL compliant solution. Hence, this paper addresses the key constraints of the wireless technology and demonstrates the proof-of-concept through a field trial.
{"title":"Towards the development of a SIL compliant wireless hydrocarbon leakage detection system","authors":"Waqas Ikram, Niklas Jansson, T. Harvei, B. Fismen, J. Svare, N. Aakvaag, Stig Petersen, Simon Carlsen","doi":"10.1109/ETFA.2013.6647986","DOIUrl":"https://doi.org/10.1109/ETFA.2013.6647986","url":null,"abstract":"Wireless communication is one of the fastest growing technologies in process automation and now targets main stream applications. One such application is a safety application; it is unique in its own rights, as any problem with safety related equipment, network or system can compromise on-site safety. For the wired networks which serve safety applications, they are designed to ensure QoS. Therefore, controlling delay, jitter, packet loss rate and bandwidth is critical. To achieve the same performance over an envisioned wireless network with shared communication medium, various problems are to be dealt with. In this regard, this paper is an effort towards the design of a SIL compliant solution. Hence, this paper addresses the key constraints of the wireless technology and demonstrates the proof-of-concept through a field trial.","PeriodicalId":106678,"journal":{"name":"2013 IEEE 18th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129094920","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 : 2013-10-28DOI: 10.1109/ETFA.2013.6648004
P. Thierry, L. George, Jean-Marc Lacroix
Safety Critical systems are those systems which may endanger human lives if a failure occurs. This is the case, for example, in avionics and in modern vehicles. Security critical systems contains data or knowledge that should stay confidential. Depending on the impact of such revelation, the security level requested varies. In today's modern vehicles, many safety-critical subsystems are also security critical. These subsystems are usually interconnected through a network, each subsystem having different criticality levels. Problems come when low criticality (e.g. a multimedia application) subsystems need to exchange information with high criticality ones. If nothing is done, the low criticality subsystem inherits the requirements of the higher criticality system that it is communicating with, generating high certification costs. Such a problem increases in complex vehicles vetronic systems with advanced technologies such as United Nation peace protection armoured vehicles and some vehicles used by public services. This is not acceptable when certification is required for only a subset of subsystems. In this paper we define systems having heterogeneous communicating subsystems with multi-criticality and multi-security issues as systronic systems. This article contributes to an initial framework for the design of a systronic system with the concept of a connector that respects safety and security constraints. The goal of this connector is to control communications between different subsystems, while preserving the safety and the security of each subsystem without additional costs.
{"title":"A framework for a secure embedded filtering connector for multi-criticality systronic systems","authors":"P. Thierry, L. George, Jean-Marc Lacroix","doi":"10.1109/ETFA.2013.6648004","DOIUrl":"https://doi.org/10.1109/ETFA.2013.6648004","url":null,"abstract":"Safety Critical systems are those systems which may endanger human lives if a failure occurs. This is the case, for example, in avionics and in modern vehicles. Security critical systems contains data or knowledge that should stay confidential. Depending on the impact of such revelation, the security level requested varies. In today's modern vehicles, many safety-critical subsystems are also security critical. These subsystems are usually interconnected through a network, each subsystem having different criticality levels. Problems come when low criticality (e.g. a multimedia application) subsystems need to exchange information with high criticality ones. If nothing is done, the low criticality subsystem inherits the requirements of the higher criticality system that it is communicating with, generating high certification costs. Such a problem increases in complex vehicles vetronic systems with advanced technologies such as United Nation peace protection armoured vehicles and some vehicles used by public services. This is not acceptable when certification is required for only a subset of subsystems. In this paper we define systems having heterogeneous communicating subsystems with multi-criticality and multi-security issues as systronic systems. This article contributes to an initial framework for the design of a systronic system with the concept of a connector that respects safety and security constraints. The goal of this connector is to control communications between different subsystems, while preserving the safety and the security of each subsystem without additional costs.","PeriodicalId":106678,"journal":{"name":"2013 IEEE 18th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"421 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116686792","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 : 2013-10-28DOI: 10.1109/ETFA.2013.6647965
Kristoph Keunecke, G. Scholl
Inertial navigation systems are frequently employed in robotic applications. It is well known that if they are used without the assistance of a reference system, position failures can increase rapidly in the course of time. This article presents various zero-velocity detection routines to reduce the position instability of robots equipped with unaided strapdown inertial navigation systems in standstill. To assess the detection performance under several environmental conditions such as varying temperature investigations are performed by various simulations as a function of noise level. The acceleration sensor signal was generated by a data synthesizer based on typical accelerometer noise characteristics. It can be shown that especially normality tests are independent from environmental fluctuations resulting in a high navigation accuracy.
{"title":"Reducing position instability of unaided inertial navigation systems in standstill","authors":"Kristoph Keunecke, G. Scholl","doi":"10.1109/ETFA.2013.6647965","DOIUrl":"https://doi.org/10.1109/ETFA.2013.6647965","url":null,"abstract":"Inertial navigation systems are frequently employed in robotic applications. It is well known that if they are used without the assistance of a reference system, position failures can increase rapidly in the course of time. This article presents various zero-velocity detection routines to reduce the position instability of robots equipped with unaided strapdown inertial navigation systems in standstill. To assess the detection performance under several environmental conditions such as varying temperature investigations are performed by various simulations as a function of noise level. The acceleration sensor signal was generated by a data synthesizer based on typical accelerometer noise characteristics. It can be shown that especially normality tests are independent from environmental fluctuations resulting in a high navigation accuracy.","PeriodicalId":106678,"journal":{"name":"2013 IEEE 18th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116890611","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 : 2013-10-28DOI: 10.1109/ETFA.2013.6648062
Florian Angerer, Herbert Prähofer, R. Ramler, Friedrich Grillenberger
A call graph of a program represents the information which executable program element calls which other executable program elements. Based on the call graph, points-to sets can be computed, which represent the memory locations a reference variable can possibly point to. Call graph and points-to sets provide important information for static program analysis. This is especially true for PLC programs which heavily use pointer variables. However, due to the complexity of the algorithms, call graph and points-to analysis methods are not widely available in static analysis. In this paper, we present an approach for call graph and points-to analysis of IEC 61131-3 programs. We present the algorithm for computing call graph and points-to sets and its implementation in a tool environment, show several different application scenarios, and present first results from industrial application.
{"title":"Points-to analysis of IEC 61131-3 programs: Implementation and application","authors":"Florian Angerer, Herbert Prähofer, R. Ramler, Friedrich Grillenberger","doi":"10.1109/ETFA.2013.6648062","DOIUrl":"https://doi.org/10.1109/ETFA.2013.6648062","url":null,"abstract":"A call graph of a program represents the information which executable program element calls which other executable program elements. Based on the call graph, points-to sets can be computed, which represent the memory locations a reference variable can possibly point to. Call graph and points-to sets provide important information for static program analysis. This is especially true for PLC programs which heavily use pointer variables. However, due to the complexity of the algorithms, call graph and points-to analysis methods are not widely available in static analysis. In this paper, we present an approach for call graph and points-to analysis of IEC 61131-3 programs. We present the algorithm for computing call graph and points-to sets and its implementation in a tool environment, show several different application scenarios, and present first results from industrial application.","PeriodicalId":106678,"journal":{"name":"2013 IEEE 18th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117040920","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 : 2013-10-28DOI: 10.1109/ETFA.2013.6648139
Federico Ciccozzi
The complexity of modern embedded systems is ever increasing and the selection of target platforms is shifting from homogeneous to more heterogeneous and powerful configurations. In our previous works, we exploited the power of model-driven techniques to deal with such complexity by enabling the automatic generation of full-fledged functional code from UML models enriched with ALF action code. Nevertheless, the scope was bounded to CPU-based platforms. In this work we propose a preliminary definition of the means to build upon the current code generator to enable the generation of code targeting heterogeneous platforms, more specifically conceiving mixed CPU-GPU configurations. The aim is to minimise the effort of the user in modelling platform-related information by embedding the greatest feasible amount of it into the transformation process.
{"title":"Towards code generation from design models for embedded systems on heterogeneous CPU-GPU platforms","authors":"Federico Ciccozzi","doi":"10.1109/ETFA.2013.6648139","DOIUrl":"https://doi.org/10.1109/ETFA.2013.6648139","url":null,"abstract":"The complexity of modern embedded systems is ever increasing and the selection of target platforms is shifting from homogeneous to more heterogeneous and powerful configurations. In our previous works, we exploited the power of model-driven techniques to deal with such complexity by enabling the automatic generation of full-fledged functional code from UML models enriched with ALF action code. Nevertheless, the scope was bounded to CPU-based platforms. In this work we propose a preliminary definition of the means to build upon the current code generator to enable the generation of code targeting heterogeneous platforms, more specifically conceiving mixed CPU-GPU configurations. The aim is to minimise the effort of the user in modelling platform-related information by embedding the greatest feasible amount of it into the transformation process.","PeriodicalId":106678,"journal":{"name":"2013 IEEE 18th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116165093","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 : 2013-10-28DOI: 10.1109/ETFA.2013.6648137
David Gessner, J. Proenza, M. Barranco, L. Almeida
Distributed embedded systems have traditionally been designed using static approaches, i.e., assuming a static environment. Such approaches, however, cannot guarantee continuous operation under dynamic environments that impose new requirements upon a system as time passes. As a solution, flexible approaches have been proposed. One such approach that allows a system to adapt to changing real-time requirements is the Flexible Time-Triggered (FTT) communication paradigm. Nevertheless, if continuous operation under dynamic environments is desired, then flexibility is not enough. Indeed, it is also crucial for the system to be sufficiently reliable. In this paper we therefore explore some design ideas to make FTT highly reliable through fault tolerance by using replication. As a starting point we will use the switch of the Hard Real-Time Ethernet Switching (HaRTES) implementation of FTT.
{"title":"Towards a Flexible Time-Triggered replicated star for ethernet","authors":"David Gessner, J. Proenza, M. Barranco, L. Almeida","doi":"10.1109/ETFA.2013.6648137","DOIUrl":"https://doi.org/10.1109/ETFA.2013.6648137","url":null,"abstract":"Distributed embedded systems have traditionally been designed using static approaches, i.e., assuming a static environment. Such approaches, however, cannot guarantee continuous operation under dynamic environments that impose new requirements upon a system as time passes. As a solution, flexible approaches have been proposed. One such approach that allows a system to adapt to changing real-time requirements is the Flexible Time-Triggered (FTT) communication paradigm. Nevertheless, if continuous operation under dynamic environments is desired, then flexibility is not enough. Indeed, it is also crucial for the system to be sufficiently reliable. In this paper we therefore explore some design ideas to make FTT highly reliable through fault tolerance by using replication. As a starting point we will use the switch of the Hard Real-Time Ethernet Switching (HaRTES) implementation of FTT.","PeriodicalId":106678,"journal":{"name":"2013 IEEE 18th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114792332","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 : 2013-10-28DOI: 10.1109/ETFA.2013.6648149
P. Ferrari, A. Flammini, S. Rinaldi, E. Sisinni, G. Prytz
Real-time networks for substations automation systems are based on ICT technologies and they may take great advantages from ultra recent network technological improvements. A careful evaluation of the performance enhancement is required. Due to cost and system complexity, such an analysis can be performed only using a dedicated simulation environment, but the currently available simulation libraries are not focused on lower layers (L1, PHY, and L2 MAC). The main objective of this work is to introduce the architecture of a modular network simulator, with suitable models of L1 and L2 Ethernet layers, for the simulation and co-simulation of substation automation Real-time Ethernet networks. The modular simulator includes interfaces for both co-simulation with FPGA-hardware board and real network, and co-simulation with automation application software (e.g. IEC61850 SCADA system, etc.).
{"title":"Co-simulation of network infrastructure for substation automation systems","authors":"P. Ferrari, A. Flammini, S. Rinaldi, E. Sisinni, G. Prytz","doi":"10.1109/ETFA.2013.6648149","DOIUrl":"https://doi.org/10.1109/ETFA.2013.6648149","url":null,"abstract":"Real-time networks for substations automation systems are based on ICT technologies and they may take great advantages from ultra recent network technological improvements. A careful evaluation of the performance enhancement is required. Due to cost and system complexity, such an analysis can be performed only using a dedicated simulation environment, but the currently available simulation libraries are not focused on lower layers (L1, PHY, and L2 MAC). The main objective of this work is to introduce the architecture of a modular network simulator, with suitable models of L1 and L2 Ethernet layers, for the simulation and co-simulation of substation automation Real-time Ethernet networks. The modular simulator includes interfaces for both co-simulation with FPGA-hardware board and real network, and co-simulation with automation application software (e.g. IEC61850 SCADA system, etc.).","PeriodicalId":106678,"journal":{"name":"2013 IEEE 18th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127204463","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 : 2013-10-28DOI: 10.1109/ETFA.2013.6648028
Hendrik Thamer, H. Kost, Daniel Weimer, B. Scholz-Reiter
Unloading of standard containers within logistic processes is mainly performed manually. Amongst gripping technology, the development of a robot vision system for recognizing different shaped logistic goods is a major technical obstacle for developing robotic systems for automatic unloading of containers. Goods can be arbitrarily placed inside a container and the resulting packaging scenarios usually have a high degree of occlusion. Existing systems and approaches use range information acquired by laser scanners for recognizing and localizing goods inside of containers. They are restricted to a single shape class of goods and often have limited size ranges for goods. This paper presents a robot vision for recognizing and localizing differently shaped and sized objects in piled packaging scenarios using range data acquired by different kinds of range sensors. After a specific segmentation step, different shaped partial surfaces are detected and classified in point cloud data and combined to complete logistic goods. The system is evaluated with real and simulated sensor data from different packaging scenarios.
{"title":"A 3D-robot vision system for automatic unloading of containers","authors":"Hendrik Thamer, H. Kost, Daniel Weimer, B. Scholz-Reiter","doi":"10.1109/ETFA.2013.6648028","DOIUrl":"https://doi.org/10.1109/ETFA.2013.6648028","url":null,"abstract":"Unloading of standard containers within logistic processes is mainly performed manually. Amongst gripping technology, the development of a robot vision system for recognizing different shaped logistic goods is a major technical obstacle for developing robotic systems for automatic unloading of containers. Goods can be arbitrarily placed inside a container and the resulting packaging scenarios usually have a high degree of occlusion. Existing systems and approaches use range information acquired by laser scanners for recognizing and localizing goods inside of containers. They are restricted to a single shape class of goods and often have limited size ranges for goods. This paper presents a robot vision for recognizing and localizing differently shaped and sized objects in piled packaging scenarios using range data acquired by different kinds of range sensors. After a specific segmentation step, different shaped partial surfaces are detected and classified in point cloud data and combined to complete logistic goods. The system is evaluated with real and simulated sensor data from different packaging scenarios.","PeriodicalId":106678,"journal":{"name":"2013 IEEE 18th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125890657","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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