Pub Date : 2004-04-19DOI: 10.1109/CCNC.2004.1286837
Xuhui Hu, Yong Liu, M. Lee, T. Saadawi
In wireless sensor networks, the multihop routes between sensors and sinks (data collectors) suffer breakage or damage because of the movement of targets and sinks, or the power exhaustion of some sensors. An efficient route maintenance and update protocol should give attention to both route rediscovery overhead and route optimization. In most flooding based routing protocols, route discovery/rediscovery packets are broadcast omni-directionally, which causes significant communication overhead as well as wireless channel contention. Query localization (QL) protocol (Castenada, R. et al., ACM/Kluwer Wireless Networks Journal, vol.8, no.2, p.137-51, 2002) limits the broadcast of route rediscovery packets within the local region of the old routes. However, as new routes formed under QL have to share most parts with old routes, route optimization is penalized. We propose to update the route by using the information of the old route, but at the same time, select a new route not necessarily overlapping the old one. This virtue is especially important to route-wide update cases, such as continuous movement of targets and sinks, and renovation of worn-out routes. Simulations show that, our new protocol always builds a fresher and better route with a very low control overhead.
在无线传感器网络中，传感器和接收器(数据采集器)之间的多跳路由会因目标和接收器的移动或某些传感器的电量耗尽而中断或损坏。一个有效的路由维护和更新协议应该同时考虑路由重发现开销和路由优化。在大多数基于泛洪的路由协议中，路由发现/再发现数据包是全向广播的，这导致了大量的通信开销和无线信道争用。查询定位(QL)协议(Castenada, R. et al.， ACM/Kluwer无线网络杂志，第8卷，第8期)。(2, p.137-51, 2002)限制了在旧路由的本地区域内广播路由重新发现数据包。然而，由于在QL下形成的新路线必须与旧路线共享大部分部分，因此路线优化受到惩罚。我们建议利用旧路线的信息更新路线，但同时选择一条不一定与旧路线重叠的新路线。这一优点对于路由范围内的更新情况尤其重要，例如目标和汇聚点的连续移动，以及旧路由的更新。仿真结果表明，新协议总能以极低的控制开销构建出更新颖、更好的路由。
{"title":"Route update and repair in wireless sensor networks","authors":"Xuhui Hu, Yong Liu, M. Lee, T. Saadawi","doi":"10.1109/CCNC.2004.1286837","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286837","url":null,"abstract":"In wireless sensor networks, the multihop routes between sensors and sinks (data collectors) suffer breakage or damage because of the movement of targets and sinks, or the power exhaustion of some sensors. An efficient route maintenance and update protocol should give attention to both route rediscovery overhead and route optimization. In most flooding based routing protocols, route discovery/rediscovery packets are broadcast omni-directionally, which causes significant communication overhead as well as wireless channel contention. Query localization (QL) protocol (Castenada, R. et al., ACM/Kluwer Wireless Networks Journal, vol.8, no.2, p.137-51, 2002) limits the broadcast of route rediscovery packets within the local region of the old routes. However, as new routes formed under QL have to share most parts with old routes, route optimization is penalized. We propose to update the route by using the information of the old route, but at the same time, select a new route not necessarily overlapping the old one. This virtue is especially important to route-wide update cases, such as continuous movement of targets and sinks, and renovation of worn-out routes. Simulations show that, our new protocol always builds a fresher and better route with a very low control overhead.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126473690","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 : 2004-04-19DOI: 10.1109/CCNC.2004.1286894
R. Hall, H. Cervantes
The open services gateway initiative (OSGi) defines and promotes open specifications for the delivery of managed services into networked environments. A key element of this initiative is the OSGi framework, which is a lightweight framework for deploying and executing service-oriented applications. This paper focuses on the OSGi framework by first discussing some implementation details of an open source implementation of the OSGi framework, called Oscar. The paper then presents issues that arose or whose importance was magnified through implementing and/or using the OSGi framework.
{"title":"An OSGi implementation and experience report","authors":"R. Hall, H. Cervantes","doi":"10.1109/CCNC.2004.1286894","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286894","url":null,"abstract":"The open services gateway initiative (OSGi) defines and promotes open specifications for the delivery of managed services into networked environments. A key element of this initiative is the OSGi framework, which is a lightweight framework for deploying and executing service-oriented applications. This paper focuses on the OSGi framework by first discussing some implementation details of an open source implementation of the OSGi framework, called Oscar. The paper then presents issues that arose or whose importance was magnified through implementing and/or using the OSGi framework.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121573796","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 : 2004-04-19DOI: 10.1109/CCNC.2004.1286876
Tzu-Ming Lin, Juin-Jia Dai
Smart antennas have been used to enhance the performance of ad hoc networks. The paper proposes a collision free MAC (media access control) protocol using smart antennas in wireless ad hoc networks. The physical communication links are converted into several logical communication link groups, and the MNs (mobile nodes) with logical communication links that are in the same link group can transmit packets to the desired sector spaces at the same time. Every MN can transfer data in the space and cause no interference to each other. The proposed mechanism can increase channel utilization and limit transmission delay. The superior transmission delay and utilization results compared with the traditional RTS/CTS and the central control mechanism are also analyzed in the simulation. The results show that the proposed mechanism can increase the channel utilization and limit the transmission delay efficiently.
{"title":"A collision free MAC protocol using smart antenna in ad hoc networks","authors":"Tzu-Ming Lin, Juin-Jia Dai","doi":"10.1109/CCNC.2004.1286876","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286876","url":null,"abstract":"Smart antennas have been used to enhance the performance of ad hoc networks. The paper proposes a collision free MAC (media access control) protocol using smart antennas in wireless ad hoc networks. The physical communication links are converted into several logical communication link groups, and the MNs (mobile nodes) with logical communication links that are in the same link group can transmit packets to the desired sector spaces at the same time. Every MN can transfer data in the space and cause no interference to each other. The proposed mechanism can increase channel utilization and limit transmission delay. The superior transmission delay and utilization results compared with the traditional RTS/CTS and the central control mechanism are also analyzed in the simulation. The results show that the proposed mechanism can increase the channel utilization and limit the transmission delay efficiently.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122282601","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 : 2004-04-19DOI: 10.1109/CCNC.2004.1286873
G. Papadimitriou
A new medium access control protocol for broadcast LANs, which is capable of achieving a high performance under bursty traffic conditions, is introduced. According to the proposed protocol, the network stations are separated into groups. All the groups are granted permission to transmit in a round-robin fashion. The main objective of the grouping algorithm is to have exactly one ready station in each group. In this way, idle slots and collisions are minimized and a nearly optimal throughput-delay performance is achieved. The grouping of stations is dynamically modified at each time slot according to the network feedback information. Due to the dynamic nature of the grouping algorithm, the protocol is capable of being adapted to the sharp changes of the stations' traffic.
{"title":"AGP: a self-adaptive MAC protocol for broadcast LANs with bursty traffic","authors":"G. Papadimitriou","doi":"10.1109/CCNC.2004.1286873","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286873","url":null,"abstract":"A new medium access control protocol for broadcast LANs, which is capable of achieving a high performance under bursty traffic conditions, is introduced. According to the proposed protocol, the network stations are separated into groups. All the groups are granted permission to transmit in a round-robin fashion. The main objective of the grouping algorithm is to have exactly one ready station in each group. In this way, idle slots and collisions are minimized and a nearly optimal throughput-delay performance is achieved. The grouping of stations is dynamically modified at each time slot according to the network feedback information. Due to the dynamic nature of the grouping algorithm, the protocol is capable of being adapted to the sharp changes of the stations' traffic.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129840667","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 : 2004-04-19DOI: 10.1109/CCNC.2004.1286828
P. Papadimitriou, C. Georghiades
It has been proposed recently to replace the cyclic prefix (CP) in OFDM transmission by zero-padding (ZP); this guarantees symbol recovery even when channel nulls are located on a subcarrier. This, though, has the disadvantage that the simple DFT-based receiver does not perform well, but results have shown that if much higher complexity turbo demodulation is used, ZP-OFDM outperforms CP-OFDM. However, by viewing N-carrier OFDM as multicode CDMA with complex spreading codes from the N-PSK alphabet, one can apply to ZP-OFDM the numerous suboptimum multiuser receivers developed for CDMA. The performance of these receivers is dictated by the correlation properties of the IDFT matrix. Therefore, we propose to "modify" the IDFT matrix used to modulate the data in ZP-OFDM so that the resulting matrix possesses better correlation properties, and hence improved performance over multipath channels can be achieved. Simulation results verify the large gains in the uncoded performance of ZP-OFDM with modified IDFT matrix compared to CP-OFDM and ZP-OFDM with the IDFT matrix.
{"title":"Zero-padded OFDM with improved performance over multipath channels","authors":"P. Papadimitriou, C. Georghiades","doi":"10.1109/CCNC.2004.1286828","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286828","url":null,"abstract":"It has been proposed recently to replace the cyclic prefix (CP) in OFDM transmission by zero-padding (ZP); this guarantees symbol recovery even when channel nulls are located on a subcarrier. This, though, has the disadvantage that the simple DFT-based receiver does not perform well, but results have shown that if much higher complexity turbo demodulation is used, ZP-OFDM outperforms CP-OFDM. However, by viewing N-carrier OFDM as multicode CDMA with complex spreading codes from the N-PSK alphabet, one can apply to ZP-OFDM the numerous suboptimum multiuser receivers developed for CDMA. The performance of these receivers is dictated by the correlation properties of the IDFT matrix. Therefore, we propose to \"modify\" the IDFT matrix used to modulate the data in ZP-OFDM so that the resulting matrix possesses better correlation properties, and hence improved performance over multipath channels can be achieved. Simulation results verify the large gains in the uncoded performance of ZP-OFDM with modified IDFT matrix compared to CP-OFDM and ZP-OFDM with the IDFT matrix.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114613214","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 : 2004-04-19DOI: 10.1109/CCNC.2004.1286888
Xiumei Yang, D. Yuan, Piming Ma, M. Jiang
A new scheme is proposed about how to make use of the unequal error protection (UEP) property of irregular low-density parity-check (LDPC) codes. By means of the construction of a weight-increasing parity-check matrix and systematic encoding, the mapping between the important information data and the elite bits of an irregular LDPC code becomes traceable and tractable. Thus, the inherent UEP property of irregular LDPC codes is not the theoretical interest any more. The proposed scheme makes it practical to implement UEP in system applications. Taking an irregular LDPC code with code length 10000 and code rate one half as an example, simulation results are presented over AWGN channels. The validity of the proposed scheme is verified by simulation.
{"title":"New research on unequal error protection (UEP) property of irregular LDPC codes","authors":"Xiumei Yang, D. Yuan, Piming Ma, M. Jiang","doi":"10.1109/CCNC.2004.1286888","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286888","url":null,"abstract":"A new scheme is proposed about how to make use of the unequal error protection (UEP) property of irregular low-density parity-check (LDPC) codes. By means of the construction of a weight-increasing parity-check matrix and systematic encoding, the mapping between the important information data and the elite bits of an irregular LDPC code becomes traceable and tractable. Thus, the inherent UEP property of irregular LDPC codes is not the theoretical interest any more. The proposed scheme makes it practical to implement UEP in system applications. Taking an irregular LDPC code with code length 10000 and code rate one half as an example, simulation results are presented over AWGN channels. The validity of the proposed scheme is verified by simulation.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126969740","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 : 2004-04-19DOI: 10.1109/CCNC.2004.1286847
Dongk-Kyun Kim, Ki-Il Kim, Kap-Dong Kim, I. Whang, Sang-Ha Kim
Various ALM (application layer multicast) mechanisms have been suggested to remove the barriers that block deployment of IP multicast. However, most ALM mechanisms do not consider the host group model, which is not a problematic portion, but advantageous feature of traditional IP multicast in terms of scalability, robustness, security, and transparency. Furthermore, those mechanisms build an overlay multicast network for data delivery mostly based on a simple measurement, with a few metrics, without directly considering the IP network topology. Thus, they might suffer some inefficiency, such as long join delay and large control overhead. We propose a scheme to take advantages of both IP multicast and ALM, based on two principal design factors. By adopting the host group model, our scheme can inherently acquire network topology information used to get rid of application level routing inefficiency, and to gain additional efficiency for many group members. Also, we exploit topology-awareness to reduce join delay and localize group members so that controls for setting up and maintaining overlay networks can be limited in a domain. Overall network performance is enhanced with our scheme by building an overlay network based on performance factors associated with network characteristics using a hierarchical structure.
{"title":"Scheme for scalable ALM architecture based on topology-awareness","authors":"Dongk-Kyun Kim, Ki-Il Kim, Kap-Dong Kim, I. Whang, Sang-Ha Kim","doi":"10.1109/CCNC.2004.1286847","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286847","url":null,"abstract":"Various ALM (application layer multicast) mechanisms have been suggested to remove the barriers that block deployment of IP multicast. However, most ALM mechanisms do not consider the host group model, which is not a problematic portion, but advantageous feature of traditional IP multicast in terms of scalability, robustness, security, and transparency. Furthermore, those mechanisms build an overlay multicast network for data delivery mostly based on a simple measurement, with a few metrics, without directly considering the IP network topology. Thus, they might suffer some inefficiency, such as long join delay and large control overhead. We propose a scheme to take advantages of both IP multicast and ALM, based on two principal design factors. By adopting the host group model, our scheme can inherently acquire network topology information used to get rid of application level routing inefficiency, and to gain additional efficiency for many group members. Also, we exploit topology-awareness to reduce join delay and localize group members so that controls for setting up and maintaining overlay networks can be limited in a domain. Overall network performance is enhanced with our scheme by building an overlay network based on performance factors associated with network characteristics using a hierarchical structure.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"29 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125695026","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 : 2004-04-19DOI: 10.1109/CCNC.2004.1286877
S. Mo
Ultra wide-band (UWB) radio uses pulses of very short duration, thereby spreading the energy of the radio signal very thinly over several Gigahertz bandwidth. The power spectral density (PSD) of UWB signals consists of a continuous component and a discrete component. The discrete component presents greater interference to narrow-band communication systems than the continuous component. Multi-band UWB, recently proposed to IEEE 802.15.3a, divides the working spectrum into sub-bands, in each of which one waveform is used for the impulse. In this paper, we devise an efficient mechanism to suppress the discrete PSD component of multi-band UWB.
{"title":"Phase reversion to reduce power spectral density of multi-band UWB signals","authors":"S. Mo","doi":"10.1109/CCNC.2004.1286877","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286877","url":null,"abstract":"Ultra wide-band (UWB) radio uses pulses of very short duration, thereby spreading the energy of the radio signal very thinly over several Gigahertz bandwidth. The power spectral density (PSD) of UWB signals consists of a continuous component and a discrete component. The discrete component presents greater interference to narrow-band communication systems than the continuous component. Multi-band UWB, recently proposed to IEEE 802.15.3a, divides the working spectrum into sub-bands, in each of which one waveform is used for the impulse. In this paper, we devise an efficient mechanism to suppress the discrete PSD component of multi-band UWB.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"212 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132675961","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 : 2004-04-19DOI: 10.1109/CCNC.2004.1286861
H. Aouad, A. Ibrahim, S. Tohmé
The paper characterizes the statistical distribution of the interarrival packet time of UTRAN traffic at the SAP level of the MAC layer. We analyze a simulated traffic trace of UMTS networks to characterize the nature of the aggregated flows. We chose MMPP-2 (Markov modulated Poisson process) to model the packet interarrival time.
{"title":"UTRAN traffic parameters estimation","authors":"H. Aouad, A. Ibrahim, S. Tohmé","doi":"10.1109/CCNC.2004.1286861","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286861","url":null,"abstract":"The paper characterizes the statistical distribution of the interarrival packet time of UTRAN traffic at the SAP level of the MAC layer. We analyze a simulated traffic trace of UMTS networks to characterize the nature of the aggregated flows. We chose MMPP-2 (Markov modulated Poisson process) to model the packet interarrival time.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133410772","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 : 2004-04-19DOI: 10.1109/CCNC.2004.1286832
Ping Ding, J. Holliday, Aslihan Celik
802.1x is a security protocol based on the frame structure of 802.11. It attempts to provide strong authentication, access control, and WEP (wired equivalent privacy) key management for wireless LANs. Unfortunately, 802.1x misses its goals in access control denial-of-service attacks. Currently, there are no IEEE approved ways to solve this security hole. We propose a central manager, not only to take the responsibility of an authentication server, but also to add functionality to prevent denial of service attacks. We also analyze how the 802.11 MAC layer protocol works with our solution.
{"title":"Improving the security of wireless LANs by managing 802.1x disassociation","authors":"Ping Ding, J. Holliday, Aslihan Celik","doi":"10.1109/CCNC.2004.1286832","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286832","url":null,"abstract":"802.1x is a security protocol based on the frame structure of 802.11. It attempts to provide strong authentication, access control, and WEP (wired equivalent privacy) key management for wireless LANs. Unfortunately, 802.1x misses its goals in access control denial-of-service attacks. Currently, there are no IEEE approved ways to solve this security hole. We propose a central manager, not only to take the responsibility of an authentication server, but also to add functionality to prevent denial of service attacks. We also analyze how the 802.11 MAC layer protocol works with our solution.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130990165","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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