Cognitive radio can increase spectrum utilization and avoid interference to licensed users by spectrum sensing. However limitation exists in local spectrum sensing by single cognitive radio node. Although several methods of cooperative spectrum sensing schemes are proposed, they were not checked under different SNR levels. Based on the investigation of the cooperation between CR nodes of different SNR levels, we propose the neighbor exchange of spectrum sensing information scheme aims at comprehensive thinking on increasing spectrum utilization, decreasing the interference to primary licensee and also the traffic load in whole networks.
{"title":"On the distributed cooperative spectrum sensing for cognitive radio","authors":"Wenzhong Wang, Luyong Zhang, Wei-xia Zou, Zheng Zhou","doi":"10.1109/ISCIT.2007.4392252","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392252","url":null,"abstract":"Cognitive radio can increase spectrum utilization and avoid interference to licensed users by spectrum sensing. However limitation exists in local spectrum sensing by single cognitive radio node. Although several methods of cooperative spectrum sensing schemes are proposed, they were not checked under different SNR levels. Based on the investigation of the cooperation between CR nodes of different SNR levels, we propose the neighbor exchange of spectrum sensing information scheme aims at comprehensive thinking on increasing spectrum utilization, decreasing the interference to primary licensee and also the traffic load in whole networks.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123950306","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392240
Saman Atapattu, N. Rajatheva
In this paper, we analyze the symbol error rate (SER) of a cooperative communication wireless network with a single relay system over independent and identical (i.i.d) Nakagami-m fading channels. The concept of the Alamouti code transmission technique is exploited with a two-stage protocol relay terminal operating in amplify-and-forward mode (AF). Taking these effects into account, the exact symbol error rates (SER) are determined using the moment generating function (MGF) of the total signal to noise ratio (SNR) for a particular signal in the case of M-ary phase shift keying (M-PSK) modulation schemes. Subsequently, numerical and simulation results are provided to verify the accuracy of the formulation.
{"title":"Exact SER of alamouti code transmission through amplify-forward cooperative relay over nakagami-m fading channels","authors":"Saman Atapattu, N. Rajatheva","doi":"10.1109/ISCIT.2007.4392240","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392240","url":null,"abstract":"In this paper, we analyze the symbol error rate (SER) of a cooperative communication wireless network with a single relay system over independent and identical (i.i.d) Nakagami-m fading channels. The concept of the Alamouti code transmission technique is exploited with a two-stage protocol relay terminal operating in amplify-and-forward mode (AF). Taking these effects into account, the exact symbol error rates (SER) are determined using the moment generating function (MGF) of the total signal to noise ratio (SNR) for a particular signal in the case of M-ary phase shift keying (M-PSK) modulation schemes. Subsequently, numerical and simulation results are provided to verify the accuracy of the formulation.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124239571","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392217
G. Oreku, Li Jiangzhong, F. Mtenzi
Ecommerce technology can reduce poverty by improving people's access to educations, healthy, government and financial services. Ecommerce also can help small farmers and artisans by connecting them to markets. It is clear that in rural and urban East African countries (EAC) as well as in much of the developing world-realization of this potential is not guaranteed. We study a simple bilateral model in which ICTs, are initially endowed with ability, decide sequentially (1) whether can act as producers of (eCommerce's) or as investors (rentiers) and, then (2) which quantity of investment they would like to bring, through educations and Information Technology revolutions to poor rural area people in (EAC) so that these two (education and IT) can be well adopted and defused by integrating them to commercial life. We show the existence of "natural equilibria", at which ICT become source and capital for eCommerce's while the remaining ones decide to be rentiers. We outlines a simple model to explain why a digital divide may exist between rich and poor, realizing the impact of eCommerce that can be executed over the internet has a potential towards economy growth. Low-cost access to information infrastructure is necessary prerequisite for the successful use of eCommerce by the poor, but it is not sufficient. The implementation of eCommerce projects needs to be performed by organizations and individuals who have the appropriate incentives to work with marginalized groups. Furthermore, the readinesses of EAC involvement as a community are identified as the key factors that foster local people to be connected to digital world.
{"title":"Feasibility study for ecommerce and ICT diffusion- adoption in EAC","authors":"G. Oreku, Li Jiangzhong, F. Mtenzi","doi":"10.1109/ISCIT.2007.4392217","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392217","url":null,"abstract":"Ecommerce technology can reduce poverty by improving people's access to educations, healthy, government and financial services. Ecommerce also can help small farmers and artisans by connecting them to markets. It is clear that in rural and urban East African countries (EAC) as well as in much of the developing world-realization of this potential is not guaranteed. We study a simple bilateral model in which ICTs, are initially endowed with ability, decide sequentially (1) whether can act as producers of (eCommerce's) or as investors (rentiers) and, then (2) which quantity of investment they would like to bring, through educations and Information Technology revolutions to poor rural area people in (EAC) so that these two (education and IT) can be well adopted and defused by integrating them to commercial life. We show the existence of \"natural equilibria\", at which ICT become source and capital for eCommerce's while the remaining ones decide to be rentiers. We outlines a simple model to explain why a digital divide may exist between rich and poor, realizing the impact of eCommerce that can be executed over the internet has a potential towards economy growth. Low-cost access to information infrastructure is necessary prerequisite for the successful use of eCommerce by the poor, but it is not sufficient. The implementation of eCommerce projects needs to be performed by organizations and individuals who have the appropriate incentives to work with marginalized groups. Furthermore, the readinesses of EAC involvement as a community are identified as the key factors that foster local people to be connected to digital world.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124683342","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392059
Tuo Liu, A. Mader, D. Staehle, D. Everitt
The UMTS enhanced uplink enables the efficient transport of packet-switched Internet traffic. With bit rates comparable to DSL links, it is expected that best-effort services like file-sharing become increasingly popular in UMTS networks. These services are often volume-based, which means that the sojourn time of a connection depends on the transmitted data volume. In this work, we propose an analytic model for the interference and capacity in the enhanced Uplink, which considers the impact of volume-based traffic on system capacity, other-cell interference and co-existing time-based QoS users. The analytic model is validated with a flow-level event-discrete simulation.
{"title":"Analytic modeling of the UMTS enhanced uplink in multi-cell environments with volume-based best-effort traffic","authors":"Tuo Liu, A. Mader, D. Staehle, D. Everitt","doi":"10.1109/ISCIT.2007.4392059","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392059","url":null,"abstract":"The UMTS enhanced uplink enables the efficient transport of packet-switched Internet traffic. With bit rates comparable to DSL links, it is expected that best-effort services like file-sharing become increasingly popular in UMTS networks. These services are often volume-based, which means that the sojourn time of a connection depends on the transmitted data volume. In this work, we propose an analytic model for the interference and capacity in the enhanced Uplink, which considers the impact of volume-based traffic on system capacity, other-cell interference and co-existing time-based QoS users. The analytic model is validated with a flow-level event-discrete simulation.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114611717","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4391999
S. Preradovic, I. Balbin, N. Karmakar
Development of a simple low-cost radio frequency identification (RFID) transponder for wireless sensor networks at 2.4 GHz is presented. The transponder is comprised of a rectangular patch antenna, RF modulating circuit and a low power mixed signal microcontroller from Texas Instruments. The transponder is powered by a 3 V pill-box battery and uses amplitude shift keying (ASK) backscatter modulation to communicate with a RFID reader. In this paper we present the design steps and measured results of the developed semi-passive RFID transponder.
{"title":"Development of a low-cost semi-passive transponder for sensor applications at 2.4GHz","authors":"S. Preradovic, I. Balbin, N. Karmakar","doi":"10.1109/ISCIT.2007.4391999","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4391999","url":null,"abstract":"Development of a simple low-cost radio frequency identification (RFID) transponder for wireless sensor networks at 2.4 GHz is presented. The transponder is comprised of a rectangular patch antenna, RF modulating circuit and a low power mixed signal microcontroller from Texas Instruments. The transponder is powered by a 3 V pill-box battery and uses amplitude shift keying (ASK) backscatter modulation to communicate with a RFID reader. In this paper we present the design steps and measured results of the developed semi-passive RFID transponder.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114553695","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392077
Xingyu Zhang, Xiaohong Peng
As one of the most challenging aspects of streaming video over lossy networks, the technology for controlling packet losses has attracted more and more attention. Erasure coding is one of the ideal choices to deal with this problem. In most cases, the researchers need an effective method or tool to validate the erasure codes used for dealing with different packet loss patterns. Although some previous work has been done on employing erasure codes in video streaming system, few actual buildups and experiments which involve implementation of erasure codes against real packet loss in streaming systems have been reported. In this paper, we focus on constructing a testbed that integrates loss pattern generation and erasure coding implementation into video streaming services over lossy networks. With this approach, we are able to assess the capability of erasure coding in packet loss control and compare the performances of the video streaming systems with and without erasure coding. As an example, we have implemented the Reed-Solomon (7, 5) code for protecting MPEG streaming data under random packet losses. Experiment results show that the replay quality can be improved significantly by using erasure coding in video streaming systems, and that the testbed can suggest appropriate erasure code parameters for different loss environments.
{"title":"A testbed of erasure coding on video streaming system over lossy networks","authors":"Xingyu Zhang, Xiaohong Peng","doi":"10.1109/ISCIT.2007.4392077","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392077","url":null,"abstract":"As one of the most challenging aspects of streaming video over lossy networks, the technology for controlling packet losses has attracted more and more attention. Erasure coding is one of the ideal choices to deal with this problem. In most cases, the researchers need an effective method or tool to validate the erasure codes used for dealing with different packet loss patterns. Although some previous work has been done on employing erasure codes in video streaming system, few actual buildups and experiments which involve implementation of erasure codes against real packet loss in streaming systems have been reported. In this paper, we focus on constructing a testbed that integrates loss pattern generation and erasure coding implementation into video streaming services over lossy networks. With this approach, we are able to assess the capability of erasure coding in packet loss control and compare the performances of the video streaming systems with and without erasure coding. As an example, we have implemented the Reed-Solomon (7, 5) code for protecting MPEG streaming data under random packet losses. Experiment results show that the replay quality can be improved significantly by using erasure coding in video streaming systems, and that the testbed can suggest appropriate erasure code parameters for different loss environments.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130473682","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392188
Xue Wang, Sheng Wang, Daowei Bi
Dynamic sensor nodes selection strategy refers to the optimization for achieving the tradeoff between energy consumption and effective coverage rate, enhancing energy efficiency, enlarging the effective coverage rate and prolonging the lifetime of wireless sensor networks (WSN). This paper proposes a dynamic sensor nodes selection strategy, so-called HN-GA, which uses the genetic algorithm (GA) to implement global searching and adopts the Hopfield network (HN) to reduce the search space of GA and ensure the validity of each chromosome. For evaluating the sensor nodes selection results, a combined metric based on several practically feasible measures of the energy consumption and effective coverage rate is introduced. The simulation results verify that the proposed HN-GA algorithm performs well in dynamic sensor nodes selection. With the help of HN-GA based dynamic sensor nodes selection, the lifetime and the effective coverage performance of WSN can be significantly improved. Compared to GA and HN, HN-GA has better performance in regional convergence and global searching, and it can achieve dynamic sensor nodes selection optimization efficiently, robustly and rapidly.
{"title":"Dynamic sensor nodes selection strategy for wireless sensor networks","authors":"Xue Wang, Sheng Wang, Daowei Bi","doi":"10.1109/ISCIT.2007.4392188","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392188","url":null,"abstract":"Dynamic sensor nodes selection strategy refers to the optimization for achieving the tradeoff between energy consumption and effective coverage rate, enhancing energy efficiency, enlarging the effective coverage rate and prolonging the lifetime of wireless sensor networks (WSN). This paper proposes a dynamic sensor nodes selection strategy, so-called HN-GA, which uses the genetic algorithm (GA) to implement global searching and adopts the Hopfield network (HN) to reduce the search space of GA and ensure the validity of each chromosome. For evaluating the sensor nodes selection results, a combined metric based on several practically feasible measures of the energy consumption and effective coverage rate is introduced. The simulation results verify that the proposed HN-GA algorithm performs well in dynamic sensor nodes selection. With the help of HN-GA based dynamic sensor nodes selection, the lifetime and the effective coverage performance of WSN can be significantly improved. Compared to GA and HN, HN-GA has better performance in regional convergence and global searching, and it can achieve dynamic sensor nodes selection optimization efficiently, robustly and rapidly.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130518877","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 : 2007-12-04DOI: 10.37936/ECTI-CIT.201041.54220
G. Dolecek
The modification of the conventional CIC (cascaded-integrator-comb) filter for rational sample rate conversion (SRC) in software radio (SWR) systems is presented here. The conversion factor is a ratio of two mutually prime numbers, where the decimation factor M can be expressed as a product of two integers. The overall filter realization is based on a stepped triangular form of the CIC impulse response, the corresponding expanded cosine filter, and sine-based compensation filter. This filter performs sampling rate conversion efficiently by using only additions/subtractions making it attractive for software radio (SWR) applications.
{"title":"Modified CIC filter for rational sample rate conversion","authors":"G. Dolecek","doi":"10.37936/ECTI-CIT.201041.54220","DOIUrl":"https://doi.org/10.37936/ECTI-CIT.201041.54220","url":null,"abstract":"The modification of the conventional CIC (cascaded-integrator-comb) filter for rational sample rate conversion (SRC) in software radio (SWR) systems is presented here. The conversion factor is a ratio of two mutually prime numbers, where the decimation factor M can be expressed as a product of two integers. The overall filter realization is based on a stepped triangular form of the CIC impulse response, the corresponding expanded cosine filter, and sine-based compensation filter. This filter performs sampling rate conversion efficiently by using only additions/subtractions making it attractive for software radio (SWR) applications.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130963757","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392144
Alexandre P. Almeida, Rui Dinis, F. Cercas
This paper introduces an efficient acquisition/correlation technique for DS-CDMA systems using a frequency-domain approach employing TCH-based training blocks (Tomlison, Cercas and Hughes). The classical time-domain active acquisition technique is compared with the proposed passive matched-filter type frequency domain technique. Moreover using the fact that an N-point discrete Fourier transform (DFT) can be partitioned into M smaller DFTs, we present a procedure for simultaneous decoding/despreading and synchronization that switch between 16 bit-length and 256 bit-length cyclic codes thus providing code rate variability.
{"title":"An FFT-based acquisition scheme for DS-CDM a systems","authors":"Alexandre P. Almeida, Rui Dinis, F. Cercas","doi":"10.1109/ISCIT.2007.4392144","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392144","url":null,"abstract":"This paper introduces an efficient acquisition/correlation technique for DS-CDMA systems using a frequency-domain approach employing TCH-based training blocks (Tomlison, Cercas and Hughes). The classical time-domain active acquisition technique is compared with the proposed passive matched-filter type frequency domain technique. Moreover using the fact that an N-point discrete Fourier transform (DFT) can be partitioned into M smaller DFTs, we present a procedure for simultaneous decoding/despreading and synchronization that switch between 16 bit-length and 256 bit-length cyclic codes thus providing code rate variability.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130603174","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392109
Pyung-soo, Yong-Jin Kim
In this paper, the new fast vertical handover scheme is proposed for the hierarchical Mobile IPv6 (HMIPv6) to optimize and enhance the existing fast vertical handover HMIPv6 (FVH-HMIPv6) in heterogeneous wireless access networks. The recently standardized IEEE 802.21 Media Independent Handover Function (MIHF) is adopted for the proposed FVH-HMIPv6. Firstly, the Media Independent Information Service (MIIIS) is extended by including new L3 information to provide domain prefixes of heterogeneous neighbouring mobility anchor points (MAPs), which is critical to the handover performance of proposed FVH-FMIPv6 with MIHF. Secondly, the operation procedure for the proposed scheme is described in detail. Finally, the analysis for handover performance is performed for the proposed scheme and the existing scheme, which shows the proposed FVH-HMIPv6 with MIHF can optimize and enhance the handover performance of the existing scheme.
{"title":"Hierarchical Mobile IPv6 based fast vertical handover scheme for heterogeneous wireless networks","authors":"Pyung-soo, Yong-Jin Kim","doi":"10.1109/ISCIT.2007.4392109","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392109","url":null,"abstract":"In this paper, the new fast vertical handover scheme is proposed for the hierarchical Mobile IPv6 (HMIPv6) to optimize and enhance the existing fast vertical handover HMIPv6 (FVH-HMIPv6) in heterogeneous wireless access networks. The recently standardized IEEE 802.21 Media Independent Handover Function (MIHF) is adopted for the proposed FVH-HMIPv6. Firstly, the Media Independent Information Service (MIIIS) is extended by including new L3 information to provide domain prefixes of heterogeneous neighbouring mobility anchor points (MAPs), which is critical to the handover performance of proposed FVH-FMIPv6 with MIHF. Secondly, the operation procedure for the proposed scheme is described in detail. Finally, the analysis for handover performance is performed for the proposed scheme and the existing scheme, which shows the proposed FVH-HMIPv6 with MIHF can optimize and enhance the handover performance of the existing scheme.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129818248","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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