The crucial challenge that communications industry has been wrestling with is the issue of how the underlying technologies should evolve and be used to help service providers remain competitive in an environment that for many years has been marked by increased rivalry and deregulation. Next Generation Network with its decomposed architecture addresses this challenge by taking full advantage of sophisticated technologies both to offer new services that increase service providerspsila revenues and to reduce the providers' operating costs. A strategy for evolving smoothly from modern networks to this new network structure is essential in order to minimize the required investment during the transition phase. However, any steps that are taken during this transition must make it easier for the networks to ultimately evolve to the NGN. The migration strategy proposed and explored in this paper enables the development of a capable concept of changes in the way networks are structured, and pays particular attention to the business needs of diverse service providers and network operators in doing so.
{"title":"Next Generation Service Delivery Networks: A Strategic Approach Involving Architectural Planning and Design, from a Business Perspective","authors":"N. Kryvinska, C. Strauss","doi":"10.1109/AICT.2009.74","DOIUrl":"https://doi.org/10.1109/AICT.2009.74","url":null,"abstract":"The crucial challenge that communications industry has been wrestling with is the issue of how the underlying technologies should evolve and be used to help service providers remain competitive in an environment that for many years has been marked by increased rivalry and deregulation. Next Generation Network with its decomposed architecture addresses this challenge by taking full advantage of sophisticated technologies both to offer new services that increase service providerspsila revenues and to reduce the providers' operating costs. A strategy for evolving smoothly from modern networks to this new network structure is essential in order to minimize the required investment during the transition phase. However, any steps that are taken during this transition must make it easier for the networks to ultimately evolve to the NGN. The migration strategy proposed and explored in this paper enables the development of a capable concept of changes in the way networks are structured, and pays particular attention to the business needs of diverse service providers and network operators in doing so.","PeriodicalId":409336,"journal":{"name":"2009 Fifth Advanced International Conference on Telecommunications","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122038397","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}
Recently, localization in wireless networks has gained a lot of interest; especially after some of the most interesting positioning application areas have emerged in wireless communications. The most important are the Federal Communications Commission (FCC) and the European Recommendation E112, both of which require that wireless providers should be able to locate within tens of meters users of emergency calls. In this paper, fingerprinting-based localization depending on SCORE measurements has been addressed in WiMAX networks. Fingerprinting is a good way to overcome signal propagation peculiarities caused by the propagation environment. And using the SCORE values is of great interest because of their availability during the normal operation of a standard modem. The obtained results show that using SCORE values to locate users in WiMAX networks is feasible and provides the required positioning accuracy by most of location-based services (LBS) if fingerprinting-based approaches were used to obtain localization. However, using the received signal strength (RSS) values gives higher accuracy but obtaining them is more difficult and not feasible using the current standard modems.
{"title":"Fingerprinting-Based Localization in WiMAX Networks Depending on SCORE Measurements","authors":"Mussa Bshara, L. V. Biesen","doi":"10.1109/AICT.2009.83","DOIUrl":"https://doi.org/10.1109/AICT.2009.83","url":null,"abstract":"Recently, localization in wireless networks has gained a lot of interest; especially after some of the most interesting positioning application areas have emerged in wireless communications. The most important are the Federal Communications Commission (FCC) and the European Recommendation E112, both of which require that wireless providers should be able to locate within tens of meters users of emergency calls. In this paper, fingerprinting-based localization depending on SCORE measurements has been addressed in WiMAX networks. Fingerprinting is a good way to overcome signal propagation peculiarities caused by the propagation environment. And using the SCORE values is of great interest because of their availability during the normal operation of a standard modem. The obtained results show that using SCORE values to locate users in WiMAX networks is feasible and provides the required positioning accuracy by most of location-based services (LBS) if fingerprinting-based approaches were used to obtain localization. However, using the received signal strength (RSS) values gives higher accuracy but obtaining them is more difficult and not feasible using the current standard modems.","PeriodicalId":409336,"journal":{"name":"2009 Fifth Advanced International Conference on Telecommunications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130093845","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 addresses the topology design of hierarchical Hybrid Fiber-VDSL Access Networks (HFVANs). An efficient strategy is applied to find cost-effective and survivable optical distribution networks with metaheuristics in a short time. A novel metaheuristic with only few parameters, Yin-Yang Optimization (YYO), is proposed to solve this NP-hard problem. Its mathematic modeling and YYO-based algorithms are analyzed in detail. It can be applied to similar backbone network topology designs or other discrete optimization problems. Based on numerical results, the performance of YYO is evaluated and compared with previous studies on other modern metaheuristics.
{"title":"Survivable Topology Design of Hybrid Fiber-VDSL Access Networks with a Novel Metaheuristic","authors":"R. Zhao","doi":"10.1109/AICT.2009.75","DOIUrl":"https://doi.org/10.1109/AICT.2009.75","url":null,"abstract":"This paper addresses the topology design of hierarchical Hybrid Fiber-VDSL Access Networks (HFVANs). An efficient strategy is applied to find cost-effective and survivable optical distribution networks with metaheuristics in a short time. A novel metaheuristic with only few parameters, Yin-Yang Optimization (YYO), is proposed to solve this NP-hard problem. Its mathematic modeling and YYO-based algorithms are analyzed in detail. It can be applied to similar backbone network topology designs or other discrete optimization problems. Based on numerical results, the performance of YYO is evaluated and compared with previous studies on other modern metaheuristics.","PeriodicalId":409336,"journal":{"name":"2009 Fifth Advanced International Conference on Telecommunications","volume":"2009 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127328458","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 study the call-level performance behavior of two Passive Optical Network (PON) configurations in the upstream direction: an Optical Code Division Multiple Access (OCDMA) PON and a hybrid Wavelength Division Multiplexing (WDM)-OCDMA PON. Each PON accommodates 2K service-classes, which are grouped in two service priorities. The latter are denoted by thresholds in accessing the PON resources. The input traffic is assumed quasi-random, (finite number of traffic sources). Our analysis results in recursive formulas for the calculation of the system state probabilities, as well as of the call blocking probabilities and connection failure probabilities. To evaluate the proposed models the analytical results are compared with simulation results. The comparison reveals that the accuracy of the proposed analysis is quite satisfactory.
{"title":"Blocking Analysis for Priority Classes in Hybrid WDM-OCDMA Passive Optical Networks","authors":"J. Vardakas, V. Vassilakis, M. Logothetis","doi":"10.1109/AICT.2009.85","DOIUrl":"https://doi.org/10.1109/AICT.2009.85","url":null,"abstract":"We study the call-level performance behavior of two Passive Optical Network (PON) configurations in the upstream direction: an Optical Code Division Multiple Access (OCDMA) PON and a hybrid Wavelength Division Multiplexing (WDM)-OCDMA PON. Each PON accommodates 2K service-classes, which are grouped in two service priorities. The latter are denoted by thresholds in accessing the PON resources. The input traffic is assumed quasi-random, (finite number of traffic sources). Our analysis results in recursive formulas for the calculation of the system state probabilities, as well as of the call blocking probabilities and connection failure probabilities. To evaluate the proposed models the analytical results are compared with simulation results. The comparison reveals that the accuracy of the proposed analysis is quite satisfactory.","PeriodicalId":409336,"journal":{"name":"2009 Fifth Advanced International Conference on Telecommunications","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127784925","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}
M. S. Kordafshari, Azadeh Pourkabirian, K. Faez, Ali Movaghar-Rahimabadi
In this paper, we propose an approach for routing in SPEED protocol considering residual energy in routing decisions. Due to the limited energy of a sensor node, energy-efficient routing is a very important issue in sensor networks. This approach finds energy-efficient paths for delay-constrained data in real-time traffic. The SPEED protocol does not consider any energy metric in its routing. In our approach, routing is based on a weight function, which is a combination of the three factors: Delay, Energy & Speed. Here, the node with the greatest value in the weight function is to be selected as the next hop forwarding. We increase the network lifetime by considering energy metric in routing decisions. This method aims to construct a nearly stateless routing protocol, which can be used to route data based on the nodes’ residual energy. Simulation results demonstrate that the new scheme improves network lifetime about 15% longer than the traditional SPEED protocol.
{"title":"Energy-Efficient SPEED Routing Protocol for Wireless Sensor Networks","authors":"M. S. Kordafshari, Azadeh Pourkabirian, K. Faez, Ali Movaghar-Rahimabadi","doi":"10.1109/AICT.2009.52","DOIUrl":"https://doi.org/10.1109/AICT.2009.52","url":null,"abstract":"In this paper, we propose an approach for routing in SPEED protocol considering residual energy in routing decisions. Due to the limited energy of a sensor node, energy-efficient routing is a very important issue in sensor networks. This approach finds energy-efficient paths for delay-constrained data in real-time traffic. The SPEED protocol does not consider any energy metric in its routing. In our approach, routing is based on a weight function, which is a combination of the three factors: Delay, Energy & Speed. Here, the node with the greatest value in the weight function is to be selected as the next hop forwarding. We increase the network lifetime by considering energy metric in routing decisions. This method aims to construct a nearly stateless routing protocol, which can be used to route data based on the nodes’ residual energy. Simulation results demonstrate that the new scheme improves network lifetime about 15% longer than the traditional SPEED protocol.","PeriodicalId":409336,"journal":{"name":"2009 Fifth Advanced International Conference on Telecommunications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130104753","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}
R. Ghanadan, S. Mo, Mingchuan Luo, K. Guan, J. Hsu
In this paper, we provide a general framework of distributed medium access control (DMAC) and synchronization for ad-hoc sensor networks with omni-directional antennas. Compared to existing works that focus on minimizing the energy consumption, our design objectives aim to increase the throughput, to lower the latency, and to solve hidden and exposed nodes problem in a traffic-heavy and dynamic environment. DMAC uses different transmission techniques based on the type of outbound packets, to effectively reduce the overhead and complexity of channel access coordination. At its core, DMAC relies on node activate medium access (NAMA) scheduling to coordinate collision-free transmissions. As time synchronization plays a fundamental role in DMAC scheduling, we also design a synchronization scheme tailored to multi-hop networks with heavy traffic and packet loss. We evaluate the performances of the proposed framework via extensive simulations. Our results show that DMAC provides higher system throughput compared with carrier sense multiple access/collision avoidance (CSMA/CA) scheme. In addition, the proposed synchronization scheme can achieve synchronization error within 1 mus in the presence of packet loss and measurement noise, while incurring minimal increment of overheads.
{"title":"A Novel Distributed Medium Access Control and Synchronization for Ad-Hoc Sensor Networks","authors":"R. Ghanadan, S. Mo, Mingchuan Luo, K. Guan, J. Hsu","doi":"10.1109/AICT.2009.86","DOIUrl":"https://doi.org/10.1109/AICT.2009.86","url":null,"abstract":"In this paper, we provide a general framework of distributed medium access control (DMAC) and synchronization for ad-hoc sensor networks with omni-directional antennas. Compared to existing works that focus on minimizing the energy consumption, our design objectives aim to increase the throughput, to lower the latency, and to solve hidden and exposed nodes problem in a traffic-heavy and dynamic environment. DMAC uses different transmission techniques based on the type of outbound packets, to effectively reduce the overhead and complexity of channel access coordination. At its core, DMAC relies on node activate medium access (NAMA) scheduling to coordinate collision-free transmissions. As time synchronization plays a fundamental role in DMAC scheduling, we also design a synchronization scheme tailored to multi-hop networks with heavy traffic and packet loss. We evaluate the performances of the proposed framework via extensive simulations. Our results show that DMAC provides higher system throughput compared with carrier sense multiple access/collision avoidance (CSMA/CA) scheme. In addition, the proposed synchronization scheme can achieve synchronization error within 1 mus in the presence of packet loss and measurement noise, while incurring minimal increment of overheads.","PeriodicalId":409336,"journal":{"name":"2009 Fifth Advanced International Conference on Telecommunications","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124354256","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 sensor networks, data collected by sensor nodes needs to be tagged with time and location information. Localization techniques are used to determine the location information by estimating location of a sensor node. It is well known that distance measurement errors affect the accuracy of estimated location. These errors may be due to methodical or environmental factors. In this paper, we propose AML (Adapted Multi-Lateration) by improving the existing multi-lateration technique. It is shown that the AML method is more robust to measurement errors; its mean localization error is lower than the multi-lateration technique for noisy measurements. Besides, the time complexity of the AML method is less than the multi-lateration technique since it does not require to solve the normal equation for the linear least squares problem as in the multi-lateration technique. Additionally, AML is advantageous for iterative localization where localized nodes become reference nodes and employed in the localization process. Incorporating these reference nodes in the AML equations is easier than multi-lateration technique.
{"title":"Localization in Wireless Sensor Networks with Range Measurement Errors","authors":"Gulnur Selda Kuruoglu, M. Erol-Kantarci, S. Oktug","doi":"10.1109/AICT.2009.51","DOIUrl":"https://doi.org/10.1109/AICT.2009.51","url":null,"abstract":"In sensor networks, data collected by sensor nodes needs to be tagged with time and location information. Localization techniques are used to determine the location information by estimating location of a sensor node. It is well known that distance measurement errors affect the accuracy of estimated location. These errors may be due to methodical or environmental factors. In this paper, we propose AML (Adapted Multi-Lateration) by improving the existing multi-lateration technique. It is shown that the AML method is more robust to measurement errors; its mean localization error is lower than the multi-lateration technique for noisy measurements. Besides, the time complexity of the AML method is less than the multi-lateration technique since it does not require to solve the normal equation for the linear least squares problem as in the multi-lateration technique. Additionally, AML is advantageous for iterative localization where localized nodes become reference nodes and employed in the localization process. Incorporating these reference nodes in the AML equations is easier than multi-lateration technique.","PeriodicalId":409336,"journal":{"name":"2009 Fifth Advanced International Conference on Telecommunications","volume":"128 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122756456","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}
A. Chandra-Sekaran, G. Stefansson, C. Kunze, K. Müller-Glaser, P. Weisser
During emergency response to mass casualty disasters, one of the main logistic impediments faced by the On-site Organizational Chief (OOC) is to track the patients at the disaster site. We had proposed our previous work a new system based on a location aware wireless sensor network (WSN) to overcome these impediments and assist the responders in providing efficient emergency response. In this paper we have implemented a new algorithm called Range-Based Monte Carlo Patient Localization (MPL) for real time localization of large number of patients at the disaster site. The simulation of the algorithm is done in a general scenario and its performance is evaluated by comparing it with state of the art algorithms. The simulation of MPL in a simplified disaster management mobility model verifies that it is suitable for tracking patients at the disaster site.
{"title":"A Range-Based Monte Carlo Patient Localization during Emergency Response to Crisis","authors":"A. Chandra-Sekaran, G. Stefansson, C. Kunze, K. Müller-Glaser, P. Weisser","doi":"10.1109/AICT.2009.10","DOIUrl":"https://doi.org/10.1109/AICT.2009.10","url":null,"abstract":"During emergency response to mass casualty disasters, one of the main logistic impediments faced by the On-site Organizational Chief (OOC) is to track the patients at the disaster site. We had proposed our previous work a new system based on a location aware wireless sensor network (WSN) to overcome these impediments and assist the responders in providing efficient emergency response. In this paper we have implemented a new algorithm called Range-Based Monte Carlo Patient Localization (MPL) for real time localization of large number of patients at the disaster site. The simulation of the algorithm is done in a general scenario and its performance is evaluated by comparing it with state of the art algorithms. The simulation of MPL in a simplified disaster management mobility model verifies that it is suitable for tracking patients at the disaster site.","PeriodicalId":409336,"journal":{"name":"2009 Fifth Advanced International Conference on Telecommunications","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126623952","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}
S. Obreja, M. Stanciu, E. Borcoci, S. Ciochină, R. Lupu
This paper presents the validation of an end-to-end QoS integrated management system in a multidomain test-bed environment. The integrated management system was designed and implemented in the framework of the ENTHRONE European project. This paper focuses on the network service management validation at both the Service Provide and Network Provider The Network Service Management is based the SLS management: in the core network the pSLS management is used to deal with users aggregated services, while cSLS management is used to deal with individual users services. Both functionality and scalability tests for SLS management are presented.
{"title":"Functionality and Scalability Validation for an End to End QoS Management System","authors":"S. Obreja, M. Stanciu, E. Borcoci, S. Ciochină, R. Lupu","doi":"10.1109/AICT.2009.30","DOIUrl":"https://doi.org/10.1109/AICT.2009.30","url":null,"abstract":"This paper presents the validation of an end-to-end QoS integrated management system in a multidomain test-bed environment. The integrated management system was designed and implemented in the framework of the ENTHRONE European project. This paper focuses on the network service management validation at both the Service Provide and Network Provider The Network Service Management is based the SLS management: in the core network the pSLS management is used to deal with users aggregated services, while cSLS management is used to deal with individual users services. Both functionality and scalability tests for SLS management are presented.","PeriodicalId":409336,"journal":{"name":"2009 Fifth Advanced International Conference on Telecommunications","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126631755","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}
C. Vladeanu, S. E. Assad, J. Carlach, R. Quéré, C. Paleologu
In this paper, nonlinear digital filters with finite precision are analyzed as recursive systematic convolutional (RSC) encoders. An infinite impulse response (IIR) digital filter with finite precision (wordlength of N bits) is a rate 1 RSC encoder over a Galois field GF(2N). The Frey chaotic filter is analyzed for two different wordlengths N, and it is demonstrated that this encoder can be used for trellis-coded modulation (TCM) schemes. A definition for the encoding rate is provided in the context of the new structure. The Frey encoder scheme is modified in order to reduce the encoding rate from 1 to 1/2. In fact, this modification consists in increasing the number of encoder outputs, using the same wordlength as for the input. The resulted encoders are used for two-dimensional (2D) TCM schemes. Also, the signal sets are partitioned following the Ungerboeck’s rules. The symbol error rate (SER) is estimated for all proposed structures and the results show the expected coding gains as compared to their equivalent non-encoded and linear versions.
{"title":"Chaotic Digital Encoding for 2D Trellis-Coded Modulation","authors":"C. Vladeanu, S. E. Assad, J. Carlach, R. Quéré, C. Paleologu","doi":"10.1109/AICT.2009.32","DOIUrl":"https://doi.org/10.1109/AICT.2009.32","url":null,"abstract":"In this paper, nonlinear digital filters with finite precision are analyzed as recursive systematic convolutional (RSC) encoders. An infinite impulse response (IIR) digital filter with finite precision (wordlength of N bits) is a rate 1 RSC encoder over a Galois field GF(2N). The Frey chaotic filter is analyzed for two different wordlengths N, and it is demonstrated that this encoder can be used for trellis-coded modulation (TCM) schemes. A definition for the encoding rate is provided in the context of the new structure. The Frey encoder scheme is modified in order to reduce the encoding rate from 1 to 1/2. In fact, this modification consists in increasing the number of encoder outputs, using the same wordlength as for the input. The resulted encoders are used for two-dimensional (2D) TCM schemes. Also, the signal sets are partitioned following the Ungerboeck’s rules. The symbol error rate (SER) is estimated for all proposed structures and the results show the expected coding gains as compared to their equivalent non-encoded and linear versions.","PeriodicalId":409336,"journal":{"name":"2009 Fifth Advanced International Conference on Telecommunications","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115282381","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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