Pub Date : 2004-06-11DOI: 10.1109/INCC.2004.1366586
A. Malik, S.M.A. Burney
Growth in the usage of mobile Internet services has complicated quality of service (QoS) management in cellular multimedia networks due to four objectives: maximum system efficiency in bandwidth utilization; enhanced user-perceived QoS level in terms of system protection ratio; maximum system capacity for accommodating ever increasing traffic load; least handoff rate because every handoff interrupts the negotiated QoS parameters and thus affects the application performance to an extent that depends on the period of induced interruption and type of application. Considering a GSM 900 based cellular multimedia network model, the dependency of system efficiency on the diversity of multimedia calls and handoff rate is first established; then, having determined an optimized value of protection ratio, it is established that, regardless of protection ratio value, the system's capacity depends upon the employed MAC (medium access control) protocol and handoff rate. Having confirmed numerical results by using LABVIEW 6.0 simulation software, it is concluded that, for any desired QoS level, the cellular multimedia network management requires intelligent optimization of the system efficiency and the system capacity that also depends on the employed MAC protocol and handoff rate.
{"title":"Cellular multimedia network management by optimizing efficiency, QoS level and capacity","authors":"A. Malik, S.M.A. Burney","doi":"10.1109/INCC.2004.1366586","DOIUrl":"https://doi.org/10.1109/INCC.2004.1366586","url":null,"abstract":"Growth in the usage of mobile Internet services has complicated quality of service (QoS) management in cellular multimedia networks due to four objectives: maximum system efficiency in bandwidth utilization; enhanced user-perceived QoS level in terms of system protection ratio; maximum system capacity for accommodating ever increasing traffic load; least handoff rate because every handoff interrupts the negotiated QoS parameters and thus affects the application performance to an extent that depends on the period of induced interruption and type of application. Considering a GSM 900 based cellular multimedia network model, the dependency of system efficiency on the diversity of multimedia calls and handoff rate is first established; then, having determined an optimized value of protection ratio, it is established that, regardless of protection ratio value, the system's capacity depends upon the employed MAC (medium access control) protocol and handoff rate. Having confirmed numerical results by using LABVIEW 6.0 simulation software, it is concluded that, for any desired QoS level, the cellular multimedia network management requires intelligent optimization of the system efficiency and the system capacity that also depends on the employed MAC protocol and handoff rate.","PeriodicalId":337263,"journal":{"name":"2004 International Networking and Communication Conference","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133169353","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 : 2004-06-11DOI: 10.1109/INCC.2004.1366571
Muneeb Ali, Z. Uzmi
In wireless sensor networks, the small data rate, generally 16 bits per packet, makes the overhead of globally unique network and MAC addresses, which is typically as much as the payload itself, undesirable (Elson, J. and Estrin, D. ICDCS'01, 2001). We present a node address naming scheme that assigns locally unique addresses, which could be spatially reused, to nodes in an energy efficient manner; the scheme reduces the address size by a factor of 3.6. The focus of our work is solely on clustering routing approaches (Heinzelman, W., "Application-Specific Protocol Architectures for Wireless Networks", PhD thesis, MIT, 2000). Further, we question the need for separate MAC and network addresses and show how our spatially reused locally unique node address could be used in both contexts, leading to greater energy efficiency.
在无线传感器网络中，较小的数据速率(通常为每包16位)使得全局唯一网络和MAC地址的开销(通常与有效载荷本身一样多)不受欢迎(Elson, J. and Estrin, D. ICDCS'01, 2001)。我们提出了一种节点地址命名方案，该方案以节能的方式为节点分配本地唯一的地址，这些地址可以在空间上重复使用;该方案将地址大小减少了3.6倍。我们的工作重点仅仅是集群路由方法(Heinzelman, W.，“无线网络的特定应用协议架构”，博士论文，麻省理工学院，2000)。此外，我们质疑是否需要单独的MAC地址和网络地址，并展示如何在空间上重复使用本地唯一节点地址，从而提高能源效率。
{"title":"An energy-efficient node address naming scheme for wireless sensor networks","authors":"Muneeb Ali, Z. Uzmi","doi":"10.1109/INCC.2004.1366571","DOIUrl":"https://doi.org/10.1109/INCC.2004.1366571","url":null,"abstract":"In wireless sensor networks, the small data rate, generally 16 bits per packet, makes the overhead of globally unique network and MAC addresses, which is typically as much as the payload itself, undesirable (Elson, J. and Estrin, D. ICDCS'01, 2001). We present a node address naming scheme that assigns locally unique addresses, which could be spatially reused, to nodes in an energy efficient manner; the scheme reduces the address size by a factor of 3.6. The focus of our work is solely on clustering routing approaches (Heinzelman, W., \"Application-Specific Protocol Architectures for Wireless Networks\", PhD thesis, MIT, 2000). Further, we question the need for separate MAC and network addresses and show how our spatially reused locally unique node address could be used in both contexts, leading to greater energy efficiency.","PeriodicalId":337263,"journal":{"name":"2004 International Networking and Communication Conference","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126035903","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 : 2004-06-11DOI: 10.1109/INCC.2004.1366569
A. Ahmed, Nadeem Zaidi, Ahmed
Transmission Control Protocol (TCP) is a widely accepted, reliable, end-to-end, transport layer communication protocol. It has a self generating error control mechanism to achieve reliability using error correction. It also a has flow control scheme to avoid network congestion using a window mechanism. TCP is tuned to perform well in traditional wired networks, where packet losses are primarily due to congestion. However, with the increase in wireless communication, there is an immense need of adapting TCP to the wireless environment. Packet loss in wireless networks could be due to bit error rate (BER), link failure or handoffs. If standard TCP is applied on such wireless networks without any modification, it may lead to performance degradation. To address these problems, many solutions have been proposed for TCP enhancements over wireless networks. We have analyzed the performance of New Reno, selective acknowledgements (SACK), explicit congestion notification (ECN) and Westwood by simulation. The performance was measured on the basis of average throughput, packet loss ratio and average end-to-end delay in three different situations: mobility (variable speed); link loss; both mobility and link loss. Results show that New Reno is more stable and consistent in the absence of congestion, otherwise ECN performs best.
{"title":"Performance evaluation of Transmission Control Protocol in mobile ad hoc networks","authors":"A. Ahmed, Nadeem Zaidi, Ahmed","doi":"10.1109/INCC.2004.1366569","DOIUrl":"https://doi.org/10.1109/INCC.2004.1366569","url":null,"abstract":"Transmission Control Protocol (TCP) is a widely accepted, reliable, end-to-end, transport layer communication protocol. It has a self generating error control mechanism to achieve reliability using error correction. It also a has flow control scheme to avoid network congestion using a window mechanism. TCP is tuned to perform well in traditional wired networks, where packet losses are primarily due to congestion. However, with the increase in wireless communication, there is an immense need of adapting TCP to the wireless environment. Packet loss in wireless networks could be due to bit error rate (BER), link failure or handoffs. If standard TCP is applied on such wireless networks without any modification, it may lead to performance degradation. To address these problems, many solutions have been proposed for TCP enhancements over wireless networks. We have analyzed the performance of New Reno, selective acknowledgements (SACK), explicit congestion notification (ECN) and Westwood by simulation. The performance was measured on the basis of average throughput, packet loss ratio and average end-to-end delay in three different situations: mobility (variable speed); link loss; both mobility and link loss. Results show that New Reno is more stable and consistent in the absence of congestion, otherwise ECN performs best.","PeriodicalId":337263,"journal":{"name":"2004 International Networking and Communication Conference","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122823357","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 : 2004-06-11DOI: 10.1109/INCC.2004.1366598
S. Abrar, A. Zerguine
A new algorithm is presented for the blind equalization of complex signals. This algorithm can be considered as a variant of the well-known reduced constellation algorithm (RCA). The proposed algorithm is obtained by removing the discontinuity found in the RCA cost function. The steady-state performance of the proposed algorithm is demonstrated by simulations. In addition, closed form expressions are obtained for the dispersion constants and the minimum of the cost functions. The phase-recovery and intersymbol interference optimization properties, exhibited by the proposed algorithm, are also discussed.
{"title":"A new multimodulus blind equalization algorithm","authors":"S. Abrar, A. Zerguine","doi":"10.1109/INCC.2004.1366598","DOIUrl":"https://doi.org/10.1109/INCC.2004.1366598","url":null,"abstract":"A new algorithm is presented for the blind equalization of complex signals. This algorithm can be considered as a variant of the well-known reduced constellation algorithm (RCA). The proposed algorithm is obtained by removing the discontinuity found in the RCA cost function. The steady-state performance of the proposed algorithm is demonstrated by simulations. In addition, closed form expressions are obtained for the dispersion constants and the minimum of the cost functions. The phase-recovery and intersymbol interference optimization properties, exhibited by the proposed algorithm, are also discussed.","PeriodicalId":337263,"journal":{"name":"2004 International Networking and Communication Conference","volume":"155 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127352470","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 : 2004-06-11DOI: 10.1109/INCC.2004.1366597
A. Ikram, A. Ali, A. Anjum, C. Steenberg, H. Newman, J. Bunn, M. Thomas, T. Azim
The requirement for information on portable, handheld devices demands the realization of increasingly complex applications for increasingly small and ubiquitous devices. This trend promotes the migration of technologies that were originally developed for desktop computers to handheld devices. With the onset of grid computing, users of handheld devices should be able to accomplish much more complex tasks, by accessing the processing and storage resources of the grid. This paper describes the development, features, and performance aspects of a grid enabled analysis environment designed for handheld devices. We also describe some differences in the technologies required to run these applications on desktop machines and handheld devices. In addition, we propose a prototype agent-based distributed architecture for carrying out high-speed analysis of physics data on handheld devices.
{"title":"Grid enabled data analysis on handheld devices","authors":"A. Ikram, A. Ali, A. Anjum, C. Steenberg, H. Newman, J. Bunn, M. Thomas, T. Azim","doi":"10.1109/INCC.2004.1366597","DOIUrl":"https://doi.org/10.1109/INCC.2004.1366597","url":null,"abstract":"The requirement for information on portable, handheld devices demands the realization of increasingly complex applications for increasingly small and ubiquitous devices. This trend promotes the migration of technologies that were originally developed for desktop computers to handheld devices. With the onset of grid computing, users of handheld devices should be able to accomplish much more complex tasks, by accessing the processing and storage resources of the grid. This paper describes the development, features, and performance aspects of a grid enabled analysis environment designed for handheld devices. We also describe some differences in the technologies required to run these applications on desktop machines and handheld devices. In addition, we propose a prototype agent-based distributed architecture for carrying out high-speed analysis of physics data on handheld devices.","PeriodicalId":337263,"journal":{"name":"2004 International Networking and Communication Conference","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116921426","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 : 2004-06-11DOI: 10.1109/INCC.2004.1366575
M.S. Alam, Q. Javed, M. Akbar, M. Rehman, M. B. Anwer
Nowadays the importance of intrusion detection is amplified due to the incredible increase in the number of attacks on the networks. The ubiquity of the Internet and the easy perpetration of attacks will lead to more hostile traffic. With the advent of high-speed Internet connections, organizations today find it difficult to detect intrusions. So multi sensor intrusion detection systems are inevitable. The optimum distribution of traffic to the sensors is a challenging task. We present a mechanism to split traffic to different intrusion detection sensors (e.g., SNORT based sensors) to make the task manageable. This splitting of traffic to each sensor is managed by policies enforced on the splitter by the management console. The system is adaptive in the sense that it can adjust the splitting policies for keeping load disparity among sensors reduced. This mechanism of policy-reloading also take into account the similarity between all possible pairs of policies and tries to minimize the packet duplication rate during the operation of the system. Our mechanism is based on the observation that minimizing the percentage of traffic being duplicated can enhance system performance. We also discuss the effects of the reloading of splitting policies on packet duplication rate and on the load on the sensors.
{"title":"Adaptive load balancing architecture for SNORT","authors":"M.S. Alam, Q. Javed, M. Akbar, M. Rehman, M. B. Anwer","doi":"10.1109/INCC.2004.1366575","DOIUrl":"https://doi.org/10.1109/INCC.2004.1366575","url":null,"abstract":"Nowadays the importance of intrusion detection is amplified due to the incredible increase in the number of attacks on the networks. The ubiquity of the Internet and the easy perpetration of attacks will lead to more hostile traffic. With the advent of high-speed Internet connections, organizations today find it difficult to detect intrusions. So multi sensor intrusion detection systems are inevitable. The optimum distribution of traffic to the sensors is a challenging task. We present a mechanism to split traffic to different intrusion detection sensors (e.g., SNORT based sensors) to make the task manageable. This splitting of traffic to each sensor is managed by policies enforced on the splitter by the management console. The system is adaptive in the sense that it can adjust the splitting policies for keeping load disparity among sensors reduced. This mechanism of policy-reloading also take into account the similarity between all possible pairs of policies and tries to minimize the packet duplication rate during the operation of the system. Our mechanism is based on the observation that minimizing the percentage of traffic being duplicated can enhance system performance. We also discuss the effects of the reloading of splitting policies on packet duplication rate and on the load on the sensors.","PeriodicalId":337263,"journal":{"name":"2004 International Networking and Communication Conference","volume":"46 15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123930341","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 : 2004-06-11DOI: 10.1109/INCC.2004.1366600
M.B. Malik, E. Mohammad, M. A. Maud
State-space recursive least-squares (SSRLS) is a new addition to the family of RLS adaptive filters. Beginning with a review of SSRLS, we show that this time-varying filter converges to an LTI (linear time invariant) filter. With observation noise as the input, BIBO (bounded input, bounded output) stability of the estimator is discussed next. We carry out the convergence analysis of SSRLS and its steady-state counterpart. Our discussion includes convergence in mean, mean-square error, mean-square deviation and learning curves. This development is imperative for a complete understanding of SSRLS to aid a designer to make the best use of the filter in advanced applications and analysis.
{"title":"Convergence analysis of state-space recursive least-squares","authors":"M.B. Malik, E. Mohammad, M. A. Maud","doi":"10.1109/INCC.2004.1366600","DOIUrl":"https://doi.org/10.1109/INCC.2004.1366600","url":null,"abstract":"State-space recursive least-squares (SSRLS) is a new addition to the family of RLS adaptive filters. Beginning with a review of SSRLS, we show that this time-varying filter converges to an LTI (linear time invariant) filter. With observation noise as the input, BIBO (bounded input, bounded output) stability of the estimator is discussed next. We carry out the convergence analysis of SSRLS and its steady-state counterpart. Our discussion includes convergence in mean, mean-square error, mean-square deviation and learning curves. This development is imperative for a complete understanding of SSRLS to aid a designer to make the best use of the filter in advanced applications and analysis.","PeriodicalId":337263,"journal":{"name":"2004 International Networking and Communication Conference","volume":"66 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122588733","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 : 2004-06-11DOI: 10.1109/INCC.2004.1366561
R. Pirzada
Summary form only given, as follows. The presentation discussed the issues carriers have been facing in the access and metropolitan networks (the areas where most capital spending is still happening), and how these networks are evolving using next generation technologies and what factors are most important to them. It also discussed the technologies that are being deployed by carriers in emerging markets and how some of them may be applicable to Pakistan.
{"title":"Current trends in carrier networks - what can Pakistan do?","authors":"R. Pirzada","doi":"10.1109/INCC.2004.1366561","DOIUrl":"https://doi.org/10.1109/INCC.2004.1366561","url":null,"abstract":"Summary form only given, as follows. The presentation discussed the issues carriers have been facing in the access and metropolitan networks (the areas where most capital spending is still happening), and how these networks are evolving using next generation technologies and what factors are most important to them. It also discussed the technologies that are being deployed by carriers in emerging markets and how some of them may be applicable to Pakistan.","PeriodicalId":337263,"journal":{"name":"2004 International Networking and Communication Conference","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124870709","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 : 2004-06-11DOI: 10.1109/INCC.2004.1366565
F. Haque, S. Ahmed
Summary form only given as follows. This tutorial covers the hardware architecture of an Internet router. Internet routers are used in the Internet core and are becoming increasingly mission critical to all services being offered over the Internet. The tutorial discusses the functionality and features of a router and the features that make up an Internet router. It then takes the audience through the fundamental building blocks of a routing system. The presentation allows the audience to identify and analyze the fundamental building blocks of a router and the architectural issues involved in building a high performance router. It covers, amongst others, switching, packet lookup and congestion management schemes.
{"title":"Overview of router architectures","authors":"F. Haque, S. Ahmed","doi":"10.1109/INCC.2004.1366565","DOIUrl":"https://doi.org/10.1109/INCC.2004.1366565","url":null,"abstract":"Summary form only given as follows. This tutorial covers the hardware architecture of an Internet router. Internet routers are used in the Internet core and are becoming increasingly mission critical to all services being offered over the Internet. The tutorial discusses the functionality and features of a router and the features that make up an Internet router. It then takes the audience through the fundamental building blocks of a routing system. The presentation allows the audience to identify and analyze the fundamental building blocks of a router and the architectural issues involved in building a high performance router. It covers, amongst others, switching, packet lookup and congestion management schemes.","PeriodicalId":337263,"journal":{"name":"2004 International Networking and Communication Conference","volume":"520 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116265167","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 : 2004-06-11DOI: 10.1109/INCC.2004.1366577
S. Hussain, S.A.H. Shah, M. I. Sheikh
A simple stochastic gradient algorithm for adaptation of complex baseband weights of the transmit antenna at the base station by feedback from the mobile is presented. In order to converge to the optimal weights of the transmit antenna, the algorithm relies on two feedbacks from the mobile. The first feedback consist of a bit that indicates which of the two normalized perturbed weights sent along with the pilot signal from the base station delivered more power to the mobile. The second feedback consists of the difference of the powers delivered by the two normalized perturbed weights. The second feedback is sent only when the power difference decreases as compared to the previous minimum stored power difference. Utilizing these two feedbacks, our algorithm at the base station updates the complex base weights of the transmit antenna. It makes a coarse stochastic gradient algorithm and converges to those weights that maximize the power delivered to the receiver. This has been confirmed by simulations.
{"title":"A mobile tracking algorithm for adaptive array smart antennas by adapting the weights of the transmit antenna","authors":"S. Hussain, S.A.H. Shah, M. I. Sheikh","doi":"10.1109/INCC.2004.1366577","DOIUrl":"https://doi.org/10.1109/INCC.2004.1366577","url":null,"abstract":"A simple stochastic gradient algorithm for adaptation of complex baseband weights of the transmit antenna at the base station by feedback from the mobile is presented. In order to converge to the optimal weights of the transmit antenna, the algorithm relies on two feedbacks from the mobile. The first feedback consist of a bit that indicates which of the two normalized perturbed weights sent along with the pilot signal from the base station delivered more power to the mobile. The second feedback consists of the difference of the powers delivered by the two normalized perturbed weights. The second feedback is sent only when the power difference decreases as compared to the previous minimum stored power difference. Utilizing these two feedbacks, our algorithm at the base station updates the complex base weights of the transmit antenna. It makes a coarse stochastic gradient algorithm and converges to those weights that maximize the power delivered to the receiver. This has been confirmed by simulations.","PeriodicalId":337263,"journal":{"name":"2004 International Networking and Communication Conference","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133483368","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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