Pub Date : 2011-05-25DOI: 10.1109/ISAM.2011.5942328
Hakan Akillioglu, M. Onori
Production planning and control strategies have been changing in line with the constant change on product and customer requirements, under the light of technological and scientific advancements. Production systems which are based on mass production became obsolete in time hence companies, being profit oriented, are in need of new solutions towards mass customization to handle rapidly changing market conditions. To deal with this issue, production systems and production planning strategies have to be complementing each other. In this paper Evolvable Production Systems and its compatibility to Just in Time (JIT) Production compared to Material Requirement Planning (MRP) will be discussed.
{"title":"Evolvable production systems and impacts on production planning","authors":"Hakan Akillioglu, M. Onori","doi":"10.1109/ISAM.2011.5942328","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942328","url":null,"abstract":"Production planning and control strategies have been changing in line with the constant change on product and customer requirements, under the light of technological and scientific advancements. Production systems which are based on mass production became obsolete in time hence companies, being profit oriented, are in need of new solutions towards mass customization to handle rapidly changing market conditions. To deal with this issue, production systems and production planning strategies have to be complementing each other. In this paper Evolvable Production Systems and its compatibility to Just in Time (JIT) Production compared to Material Requirement Planning (MRP) will be discussed.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129388813","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942322
Yuxia Li, Wanhua Zhao, Yao Cheng, Qingyu Yang, Jun Zhang
Non-synchronous error widely exists in dual-driving systems due to different electromechanical characteristics of dual-axis. An synchronous control model of dual-driving system applied on the gantry-type machine tools with travelling bridge is established in this paper aiming to account for the synchronous error. The mechanical coupling of the dual-driving systems is modeled by force analysis of the crossbeam frictions of the dual axes are identified respectively, backlash model is detected separately and Acceleration/deceleration (Acc/Dec) controller model in the CNC system is also established, then a synchronous control model allowing for above four parts is deduced. Furthermore, the good agreement between the simulation outputs and the experimental results demonstrates the validity of the proposed model. It also shows that different frictions and mechanical coupling between dual-driving axes are the key factors causing the non- synchronous error.
{"title":"Research on dual-driving synchronous control system modeling of gantry-type machine tools with traveling bridge","authors":"Yuxia Li, Wanhua Zhao, Yao Cheng, Qingyu Yang, Jun Zhang","doi":"10.1109/ISAM.2011.5942322","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942322","url":null,"abstract":"Non-synchronous error widely exists in dual-driving systems due to different electromechanical characteristics of dual-axis. An synchronous control model of dual-driving system applied on the gantry-type machine tools with travelling bridge is established in this paper aiming to account for the synchronous error. The mechanical coupling of the dual-driving systems is modeled by force analysis of the crossbeam frictions of the dual axes are identified respectively, backlash model is detected separately and Acceleration/deceleration (Acc/Dec) controller model in the CNC system is also established, then a synchronous control model allowing for above four parts is deduced. Furthermore, the good agreement between the simulation outputs and the experimental results demonstrates the validity of the proposed model. It also shows that different frictions and mechanical coupling between dual-driving axes are the key factors causing the non- synchronous error.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126618810","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942370
K. Harun, K. Cheng
The business industry has already started to address manufacturing sustainable issues primarily on industrial and corporate environmental and economic performance through the development of various eco-efficiency metrics. While this development is important, it is not enough. The metrics required to characterize the dynamic processes and systems have normally been excluded in the performance measures. Ideally, the set should include economic, environmental, and social-equity metrics. Because of their system-oriented environmental performance representation, life-cycle assessment metrics are needed to be included in such a set. This study investigates the dynamic life cycle analysis with regard to energy consumption and resources utilization due to layout design changes. Using the proposed LCS (Life Cycle Simulation) methodology, simulation of current state-of-the-art manufacturing process is performed. Integrating LCA (Life Cycle Assessment) as the basis for assessment, key process parameters were quantified and analyzed. The LCS is a promising approach as a design tool to support the design and decision makings of manufacturing processes.
{"title":"Life Cycle Simulation (LCS) approach to the manufacturing process design for sustainable manufacturing","authors":"K. Harun, K. Cheng","doi":"10.1109/ISAM.2011.5942370","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942370","url":null,"abstract":"The business industry has already started to address manufacturing sustainable issues primarily on industrial and corporate environmental and economic performance through the development of various eco-efficiency metrics. While this development is important, it is not enough. The metrics required to characterize the dynamic processes and systems have normally been excluded in the performance measures. Ideally, the set should include economic, environmental, and social-equity metrics. Because of their system-oriented environmental performance representation, life-cycle assessment metrics are needed to be included in such a set. This study investigates the dynamic life cycle analysis with regard to energy consumption and resources utilization due to layout design changes. Using the proposed LCS (Life Cycle Simulation) methodology, simulation of current state-of-the-art manufacturing process is performed. Integrating LCA (Life Cycle Assessment) as the basis for assessment, key process parameters were quantified and analyzed. The LCS is a promising approach as a design tool to support the design and decision makings of manufacturing processes.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128947410","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942319
Zhiwei Wang, Wanhua Zhao, Bingqiang Li, Jun Zhang, B. Lu
In most previous studies, hydrostatic guideways are considered as rigid without deformations. However, the deformations of slideway due to fluid film pressure affect the fluid film thickness and the pressure distribution. In this paper a fluid-structure interaction (FSI) model of hydrostatic guideways with annular gap restrictor is established. The model is solved by the finite element method (FEM). The influence of the slideway deformations on the stiffness, the flow characteristic, the pressure ratio and the film thickness are investigated. The deformations of the upper slideway decrease the stiffness of the hydrostatic guideways and increase the required flow rate. The stiffness, the volume flow rate and the deformations are linearly changed with the supply pressure. The relationship between pressure ratio and throttling length is nonlinear. The large value of αcan attain high stiffness and decrease the volume flow rate. An appropriate increase in the thickness of the upper slideway can reduce the influences of the deformations.
{"title":"Fluid-structure interactions (FSI) on static characteristics of hydrostatic guideways","authors":"Zhiwei Wang, Wanhua Zhao, Bingqiang Li, Jun Zhang, B. Lu","doi":"10.1109/ISAM.2011.5942319","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942319","url":null,"abstract":"In most previous studies, hydrostatic guideways are considered as rigid without deformations. However, the deformations of slideway due to fluid film pressure affect the fluid film thickness and the pressure distribution. In this paper a fluid-structure interaction (FSI) model of hydrostatic guideways with annular gap restrictor is established. The model is solved by the finite element method (FEM). The influence of the slideway deformations on the stiffness, the flow characteristic, the pressure ratio and the film thickness are investigated. The deformations of the upper slideway decrease the stiffness of the hydrostatic guideways and increase the required flow rate. The stiffness, the volume flow rate and the deformations are linearly changed with the supply pressure. The relationship between pressure ratio and throttling length is nonlinear. The large value of αcan attain high stiffness and decrease the volume flow rate. An appropriate increase in the thickness of the upper slideway can reduce the influences of the deformations.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127874465","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942345
T. Kumpulainen, J. Latokartano, J. Vihinen, R. Tuokko
Galvanometric laser scanners are used in various laser processing methods to create the beam movements on the workpiece. State of art applications and high speed manufacturing and processing requires often good performance in addition to the high accuracy demands. In laser scanner system, the performance is limited by optical, mechanical and control related restrictions. These limitations can be measured one by one. The errors in the scanner are however a combination of all three causes. Due to these facts, a direct measurement system for scanner accuracy evaluation does not exist. For these reasons a test pattern has been developed for indirect scanner system accuracy and performance evaluation.
{"title":"Scanner test pattern for evaluation of beam manipulation accuracy","authors":"T. Kumpulainen, J. Latokartano, J. Vihinen, R. Tuokko","doi":"10.1109/ISAM.2011.5942345","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942345","url":null,"abstract":"Galvanometric laser scanners are used in various laser processing methods to create the beam movements on the workpiece. State of art applications and high speed manufacturing and processing requires often good performance in addition to the high accuracy demands. In laser scanner system, the performance is limited by optical, mechanical and control related restrictions. These limitations can be measured one by one. The errors in the scanner are however a combination of all three causes. Due to these facts, a direct measurement system for scanner accuracy evaluation does not exist. For these reasons a test pattern has been developed for indirect scanner system accuracy and performance evaluation.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128249892","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942337
U. Dombrowski, C. Riechel, S. Schulze
Changing conditions for manufacturing enterprises force an increase of the participation of the employees. Main goals are the usage of the tacit knowledge and the experience of the employees. Furthermore the motivation may be raised, if the requirements and wishes of the workforce are taken into account. The participation is a basic element in the continuous improvement process, but also in projects like factory planning the participation will lead to better results in shorter time. In this paper the possibilities of an increased participation in the factory planning process are described.
{"title":"Enforcing employees participation in the factory planning process","authors":"U. Dombrowski, C. Riechel, S. Schulze","doi":"10.1109/ISAM.2011.5942337","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942337","url":null,"abstract":"Changing conditions for manufacturing enterprises force an increase of the participation of the employees. Main goals are the usage of the tacit knowledge and the experience of the employees. Furthermore the motivation may be raised, if the requirements and wishes of the workforce are taken into account. The participation is a basic element in the continuous improvement process, but also in projects like factory planning the participation will lead to better results in shorter time. In this paper the possibilities of an increased participation in the factory planning process are described.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130064818","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942324
B. Scholz-Reiter, D. Rippel, S. Sowade
The paradigm of autonomous control provides organizational means to face today's requirements for robust and flexible operating logistic systems. It delegates planning and execution competencies to logistic objects in order to decrease the control system's complexity. Specifically, the Autonomous Logistic Engineering Methodology is designed for modeling, simulation, and evaluation of autonomous logistic processes. However, challenges emerge concerning its scalability in case of analyzing large logistic networks. Hence, this article investigates the influence of the system's complexity and of companies' organizational independence on the methodology with the help of scenarios in production logistics and in supply chain management. It sketches possible solutions to cope with the scalability-induced effects and to enables modeling of cross-organizational logistic processes.
{"title":"Limitations in modeling autonomous logistic processes: Challenges and solutions in business process modeling","authors":"B. Scholz-Reiter, D. Rippel, S. Sowade","doi":"10.1109/ISAM.2011.5942324","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942324","url":null,"abstract":"The paradigm of autonomous control provides organizational means to face today's requirements for robust and flexible operating logistic systems. It delegates planning and execution competencies to logistic objects in order to decrease the control system's complexity. Specifically, the Autonomous Logistic Engineering Methodology is designed for modeling, simulation, and evaluation of autonomous logistic processes. However, challenges emerge concerning its scalability in case of analyzing large logistic networks. Hence, this article investigates the influence of the system's complexity and of companies' organizational independence on the methodology with the help of scenarios in production logistics and in supply chain management. It sketches possible solutions to cope with the scalability-induced effects and to enables modeling of cross-organizational logistic processes.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133545487","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942366
Anders Bjorkelund, Lisett Edstrom, M. Haage, J. Malec, K. Nilsson, P. Nugues, S. Robertz, Denis Storkle, A. Blomdell, Rolf Johansson, M. Linderoth, Anders Nilsson, A. Robertsson, Andreas Stolt, H. Bruyninckx
Robots used in manufacturing today are tailored to their tasks by system integration based on expert knowledge concerning both production and machine control. For upcoming new generations of even more flexible robot solutions, in applications such as dexterous assembly, the robot setup and programming gets even more challenging. Reuse of solutions in terms of parameters, controls, process tuning, and of software modules in general then gets increasingly important. There has been valuable progress within reuse of automation solutions when machines comply with standards and behave according to nominal models. However, more flexible robots with sensor-based manipulation skills and cognitive functions for human interaction are far too complex to manage, and solutions are rarely reusable since knowledge is either implicit in imperative software or not captured in machine readable form. We propose techniques that build on existing knowledge by converting structured data into an RDF-based knowledge base. By enhancements of industrial control systems and available engineering tools, such knowledge can be gradually extended as part of the interaction during the definition of the robot task.
{"title":"On the integration of skilled robot motions for productivity in manufacturing","authors":"Anders Bjorkelund, Lisett Edstrom, M. Haage, J. Malec, K. Nilsson, P. Nugues, S. Robertz, Denis Storkle, A. Blomdell, Rolf Johansson, M. Linderoth, Anders Nilsson, A. Robertsson, Andreas Stolt, H. Bruyninckx","doi":"10.1109/ISAM.2011.5942366","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942366","url":null,"abstract":"Robots used in manufacturing today are tailored to their tasks by system integration based on expert knowledge concerning both production and machine control. For upcoming new generations of even more flexible robot solutions, in applications such as dexterous assembly, the robot setup and programming gets even more challenging. Reuse of solutions in terms of parameters, controls, process tuning, and of software modules in general then gets increasingly important. There has been valuable progress within reuse of automation solutions when machines comply with standards and behave according to nominal models. However, more flexible robots with sensor-based manipulation skills and cognitive functions for human interaction are far too complex to manage, and solutions are rarely reusable since knowledge is either implicit in imperative software or not captured in machine readable form. We propose techniques that build on existing knowledge by converting structured data into an RDF-based knowledge base. By enhancements of industrial control systems and available engineering tools, such knowledge can be gradually extended as part of the interaction during the definition of the robot task.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116476144","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942343
M. Koho, S. Torvinen, Alexandre Torres Romiguer
This paper presents the initial results of a research project focusing on ascertaining the views of Spanish companies with regards to sustainable development. First, a literature review on the definitions, objectives and potential advantages of sustainable development and sustainable manufacturing are presented. Then, the views of Spanish companies on sustainable development are presented, based on the responses of a questionnaire survey. Further, these results are compared to a similar international study conducted by the American Management Association. The obtained results suggest that business strategy, values and top management support are essential enablers for realizing sustainability, whereas the primary challenges are problems with measurement and lack of customer demand. The results clarify the companies' current state and expectations with regard to sustainable development and are expected to assist both the industry and the academia on the way towards global sustainability.
{"title":"Objectives, enablers and challenges of sustainable development and sustainable manufacturing: Views and opinions of Spanish companies","authors":"M. Koho, S. Torvinen, Alexandre Torres Romiguer","doi":"10.1109/ISAM.2011.5942343","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942343","url":null,"abstract":"This paper presents the initial results of a research project focusing on ascertaining the views of Spanish companies with regards to sustainable development. First, a literature review on the definitions, objectives and potential advantages of sustainable development and sustainable manufacturing are presented. Then, the views of Spanish companies on sustainable development are presented, based on the responses of a questionnaire survey. Further, these results are compared to a similar international study conducted by the American Management Association. The obtained results suggest that business strategy, values and top management support are essential enablers for realizing sustainability, whereas the primary challenges are problems with measurement and lack of customer demand. The results clarify the companies' current state and expectations with regard to sustainable development and are expected to assist both the industry and the academia on the way towards global sustainability.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131478050","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 : 2011-05-25DOI: 10.1109/ISAM.2011.5942321
Haitao Liu, Wanhua Zhao, Jun Zhang, Lei Wang, Xiaobo Ma, F. Zhao
All the dynamic characteristics of machine tools, especially modal behaviors, should be known during the whole working process, in order to obtain high surface quality and accuracy of machined parts. In this paper, matrix perturbation method (MPM) is adopted to perform the modal analysis on machine tools under working state. A VMC0540d high-speed milling machine tool's modal variation within its working space is calculated by MPM and dynamically mapped. A classical modal solution method, Block-Lanczos method is used as a comparison and modal measurement experiment is carried out as verification. The results show that the machine tool's natural frequencies have a significant change with the maximum variation up to 40% during machining process. Compared with Block-Lanczos method, the time for model re-construction of first-order matrix perturbation method is obviously reduced. Modal experiments show that the MPM is credible and the error is within 10%.
{"title":"Modal analysis of machine tools during working process by matrix perturbation method","authors":"Haitao Liu, Wanhua Zhao, Jun Zhang, Lei Wang, Xiaobo Ma, F. Zhao","doi":"10.1109/ISAM.2011.5942321","DOIUrl":"https://doi.org/10.1109/ISAM.2011.5942321","url":null,"abstract":"All the dynamic characteristics of machine tools, especially modal behaviors, should be known during the whole working process, in order to obtain high surface quality and accuracy of machined parts. In this paper, matrix perturbation method (MPM) is adopted to perform the modal analysis on machine tools under working state. A VMC0540d high-speed milling machine tool's modal variation within its working space is calculated by MPM and dynamically mapped. A classical modal solution method, Block-Lanczos method is used as a comparison and modal measurement experiment is carried out as verification. The results show that the machine tool's natural frequencies have a significant change with the maximum variation up to 40% during machining process. Compared with Block-Lanczos method, the time for model re-construction of first-order matrix perturbation method is obviously reduced. Modal experiments show that the MPM is credible and the error is within 10%.","PeriodicalId":273573,"journal":{"name":"2011 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127451898","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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