Pub Date : 2003-09-21DOI: 10.1109/APCC.2003.1274410
G. Yoshida, N. Wakamiya, M. Murata, H. Miyahara
In this paper, we introduce active network technologies to a video multicast system that can satisfy heterogeneous client requests in an efficient and effective way We employ active nodes that adapt incoming video streams at the user's request by using transcoders or filters and then dynamically reorganize multicast sessions to accommodate clients. Simulation experiments demonstrate that our methods can appropriately split, merge, and move multicast groups to handle client-to-client heterogeneity.
{"title":"Dynamic organization of active video multicast in heterogeneous environment","authors":"G. Yoshida, N. Wakamiya, M. Murata, H. Miyahara","doi":"10.1109/APCC.2003.1274410","DOIUrl":"https://doi.org/10.1109/APCC.2003.1274410","url":null,"abstract":"In this paper, we introduce active network technologies to a video multicast system that can satisfy heterogeneous client requests in an efficient and effective way We employ active nodes that adapt incoming video streams at the user's request by using transcoders or filters and then dynamically reorganize multicast sessions to accommodate clients. Simulation experiments demonstrate that our methods can appropriately split, merge, and move multicast groups to handle client-to-client heterogeneity.","PeriodicalId":277507,"journal":{"name":"9th Asia-Pacific Conference on Communications (IEEE Cat. No.03EX732)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133634217","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 : 2003-09-21DOI: 10.1109/APCC.2003.1274274
M. Hayasaka, Luis Loyola, Tetsuya Miki
Real-time services over best-effort networks, such as teleconferencing over unspecified bit rate (UBR) class asynchronous transfer mode (ATM) networks or the Internet, are expected to be in high demand in the near future as such services become more cost effective. However, cell loss caused by buffer overflow at switches is a serious problem in this service class, and is responsible for degradation of the quality of service (QoS). A promising technology for improving the QoS of best-effort networks is the recovery of lost cells by forward error correction (FEC). Conventional FEC methods utilize a FEC matrix with fixed dimensions and which is usually designed to cope with the worst case of cell loss. In this paper, a new method that provides dynamic recovery capacity to deal with the current cell loss ratio through the use of a variable-dimension FEC matrix is proposed. The scheme also takes into account the coding method of the matrix to provide data prioritization. Numerical results show that the cell loss ratio and transmission efficiency of the proposed method are superior to those of conventional methods.
{"title":"Packet/cell loss recovery using variable FEC matrix for real time transport services over best effort networks","authors":"M. Hayasaka, Luis Loyola, Tetsuya Miki","doi":"10.1109/APCC.2003.1274274","DOIUrl":"https://doi.org/10.1109/APCC.2003.1274274","url":null,"abstract":"Real-time services over best-effort networks, such as teleconferencing over unspecified bit rate (UBR) class asynchronous transfer mode (ATM) networks or the Internet, are expected to be in high demand in the near future as such services become more cost effective. However, cell loss caused by buffer overflow at switches is a serious problem in this service class, and is responsible for degradation of the quality of service (QoS). A promising technology for improving the QoS of best-effort networks is the recovery of lost cells by forward error correction (FEC). Conventional FEC methods utilize a FEC matrix with fixed dimensions and which is usually designed to cope with the worst case of cell loss. In this paper, a new method that provides dynamic recovery capacity to deal with the current cell loss ratio through the use of a variable-dimension FEC matrix is proposed. The scheme also takes into account the coding method of the matrix to provide data prioritization. Numerical results show that the cell loss ratio and transmission efficiency of the proposed method are superior to those of conventional methods.","PeriodicalId":277507,"journal":{"name":"9th Asia-Pacific Conference on Communications (IEEE Cat. No.03EX732)","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116575406","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 : 2003-09-21DOI: 10.1109/APCC.2003.1274392
K. Lee
This paper looks into the audio gain line-up of TETRA 800 MHz radios. The focus is on the design of each gain block in both transmit and receive audio paths. It should be noted that the designs described in this paper are implemented based on DIMETRA-P/sup TM/ system requirements and recommendations provided by ETSI. In addition, transducer characterizations were taken into consideration in implementing the audio gain line-up that we see today.
本文研究了TETRA 800mhz无线电的音频增益线。重点是在发送和接收音频路径的每个增益块的设计。需要说明的是，本文所描述的设计是基于dimeta - p /sup TM/系统要求和ETSI提供的建议来实现的。此外，在实现我们今天看到的音频增益阵容时，还考虑了换能器特性。
{"title":"Audio gain setting in TETRA 800 MHz radio","authors":"K. Lee","doi":"10.1109/APCC.2003.1274392","DOIUrl":"https://doi.org/10.1109/APCC.2003.1274392","url":null,"abstract":"This paper looks into the audio gain line-up of TETRA 800 MHz radios. The focus is on the design of each gain block in both transmit and receive audio paths. It should be noted that the designs described in this paper are implemented based on DIMETRA-P/sup TM/ system requirements and recommendations provided by ETSI. In addition, transducer characterizations were taken into consideration in implementing the audio gain line-up that we see today.","PeriodicalId":277507,"journal":{"name":"9th Asia-Pacific Conference on Communications (IEEE Cat. No.03EX732)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132042854","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 : 2003-09-21DOI: 10.1109/APCC.2003.1274479
Sang-Kil Park, Kiyoung Kim, Jong-Su Jang, Bongnam Noh
On 22 October 2002, ICANN, the Internet's main governing body, acknowledged that a massive distributed denial-of-service attack briefly shut down seven of the 13 central Domain Name Services servers that manage Internet traffic worldwide. Prompt action by DNS server operators minimized the duration and impact of the attack, which had little effect on overall Internet performance. Intrusion detection systems are researched and developed to detect attacks from outside world since 1980. Intrusion detection systems create an alert data or log data when detect an intrusion. But Many IDS uses heterogeneous data set, so these data must be mapped to another format. IDWG in IETF proposed IDMEF. This paper designs an alert data format compatible IDMEF. The secure networking framework is consisted of SGS and CPCS. SGS acts as an intrusion detection system on edge of network ingress point, and CPCS acts as a higher-level server. SGS makes an alert data compatible IDMEF and sends it to CPCS. CPCS parses an IDMEF alert data and makes an alert object for using correlation analysis. SGS can see its area only, but CPCS can see wide network area. CPCS can detect more complex attacks as well as support integrated management through cooperating each other. In the view of alert processing we converted raw alert data to Ladon-alert data to support interoperability. We use IDMEF-compatible alert datat structure. We have designed and developed integrated IDS on gateway, and security control server on higher-level class. Then this framework offers cooperative intrusion detection, policy based controlling.
{"title":"Supporting interoperability to heterogeneous IDS in secure networking framework","authors":"Sang-Kil Park, Kiyoung Kim, Jong-Su Jang, Bongnam Noh","doi":"10.1109/APCC.2003.1274479","DOIUrl":"https://doi.org/10.1109/APCC.2003.1274479","url":null,"abstract":"On 22 October 2002, ICANN, the Internet's main governing body, acknowledged that a massive distributed denial-of-service attack briefly shut down seven of the 13 central Domain Name Services servers that manage Internet traffic worldwide. Prompt action by DNS server operators minimized the duration and impact of the attack, which had little effect on overall Internet performance. Intrusion detection systems are researched and developed to detect attacks from outside world since 1980. Intrusion detection systems create an alert data or log data when detect an intrusion. But Many IDS uses heterogeneous data set, so these data must be mapped to another format. IDWG in IETF proposed IDMEF. This paper designs an alert data format compatible IDMEF. The secure networking framework is consisted of SGS and CPCS. SGS acts as an intrusion detection system on edge of network ingress point, and CPCS acts as a higher-level server. SGS makes an alert data compatible IDMEF and sends it to CPCS. CPCS parses an IDMEF alert data and makes an alert object for using correlation analysis. SGS can see its area only, but CPCS can see wide network area. CPCS can detect more complex attacks as well as support integrated management through cooperating each other. In the view of alert processing we converted raw alert data to Ladon-alert data to support interoperability. We use IDMEF-compatible alert datat structure. We have designed and developed integrated IDS on gateway, and security control server on higher-level class. Then this framework offers cooperative intrusion detection, policy based controlling.","PeriodicalId":277507,"journal":{"name":"9th Asia-Pacific Conference on Communications (IEEE Cat. No.03EX732)","volume":"133 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134478804","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 : 2003-09-21DOI: 10.1109/APCC.2003.1274376
K. Wongrujira, P. Sookavatana, A. Seneviratne
In this paper we present the design and implementation of a framework that used JavaSpaces to support a bidding service over the decoupling network. There is a high expectation and demand for a network that could support various devices. With JavaSpaces technique, the user who requested services and the provider who provided services could read, write or take an entry task to/from the space. It was possible that one service provider could not support all client application needs. Therefore, the requirement of the chaining application and finding the lowest cost of the cascade sequence were in the interested area of middle ware network for the Internet application and adaptation. In addition, we also showed that the price and cost for support specific application could turn into the bidding concept. Hence, in this paper we focused on a research in finding an application and come out with bidding cost where we implemented JavaSpaces as a middle object pool. The result was shown by a comparison of consuming time between provision read the resource node and real time read the resource node. These ideas could extend to further perform in a recursive fashion for finding specific service applications.
{"title":"Provision resource bidding for special service provider in decoupling spaces network","authors":"K. Wongrujira, P. Sookavatana, A. Seneviratne","doi":"10.1109/APCC.2003.1274376","DOIUrl":"https://doi.org/10.1109/APCC.2003.1274376","url":null,"abstract":"In this paper we present the design and implementation of a framework that used JavaSpaces to support a bidding service over the decoupling network. There is a high expectation and demand for a network that could support various devices. With JavaSpaces technique, the user who requested services and the provider who provided services could read, write or take an entry task to/from the space. It was possible that one service provider could not support all client application needs. Therefore, the requirement of the chaining application and finding the lowest cost of the cascade sequence were in the interested area of middle ware network for the Internet application and adaptation. In addition, we also showed that the price and cost for support specific application could turn into the bidding concept. Hence, in this paper we focused on a research in finding an application and come out with bidding cost where we implemented JavaSpaces as a middle object pool. The result was shown by a comparison of consuming time between provision read the resource node and real time read the resource node. These ideas could extend to further perform in a recursive fashion for finding specific service applications.","PeriodicalId":277507,"journal":{"name":"9th Asia-Pacific Conference on Communications (IEEE Cat. No.03EX732)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133386437","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 : 2003-09-21DOI: 10.1109/APCC.2003.1274268
Ki-Il Kim, Daejin Choi, Sang-Ha Kim
While traditional multicast is scalable in the sense that they can support very large groups, there are scalability problems when network needs to support a very large number of distinct groups. This paper presents a new alternative scheme, called Xcast6+, which is an extension of Explicit Multicast (Xcast) for an efficient delivery of native multicast datagrams over IPv6 networks. The mechanism incorporates MLDv2 and a new control plane into existing Xcast, and not only does it provide the transparency of traditional multicast schemes to sources and recipients, but it also enhances the routing efficiency in networks. Since intermediate routers do not have to keep track of multicast state, it results in a more efficient and scalable mechanism to deliver native multicast datagrams. Moreover, the seamless integration of Xcast6+ in Mobile IPv6 can support multicast efficiently for mobile nodes (both sources and recipients) over IPv6 networks by avoiding tunnel avalanches and tunnel convergence. Our simulation results show distinct performance improvements of our approach. Our approach can reduce network resources when recipients are clustered in local links (i.e., "subset-dense group").
{"title":"Native multicast datagram delivery using Xcast over IPv6 networks","authors":"Ki-Il Kim, Daejin Choi, Sang-Ha Kim","doi":"10.1109/APCC.2003.1274268","DOIUrl":"https://doi.org/10.1109/APCC.2003.1274268","url":null,"abstract":"While traditional multicast is scalable in the sense that they can support very large groups, there are scalability problems when network needs to support a very large number of distinct groups. This paper presents a new alternative scheme, called Xcast6+, which is an extension of Explicit Multicast (Xcast) for an efficient delivery of native multicast datagrams over IPv6 networks. The mechanism incorporates MLDv2 and a new control plane into existing Xcast, and not only does it provide the transparency of traditional multicast schemes to sources and recipients, but it also enhances the routing efficiency in networks. Since intermediate routers do not have to keep track of multicast state, it results in a more efficient and scalable mechanism to deliver native multicast datagrams. Moreover, the seamless integration of Xcast6+ in Mobile IPv6 can support multicast efficiently for mobile nodes (both sources and recipients) over IPv6 networks by avoiding tunnel avalanches and tunnel convergence. Our simulation results show distinct performance improvements of our approach. Our approach can reduce network resources when recipients are clustered in local links (i.e., \"subset-dense group\").","PeriodicalId":277507,"journal":{"name":"9th Asia-Pacific Conference on Communications (IEEE Cat. No.03EX732)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132982842","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 : 2003-09-21DOI: 10.1109/APCC.2003.1274335
M. Mas Izyani, A. Asmahanim, M. Romli
A counter-propagating ring-laser cavity technique was demonstrated for gain-clamped and flattened erbium doped fiber amplifier. This technique was achieved by incorporating fiber Bragg grating at center wavelength 1554.88 nm with reflectivity 72.01%. A gain variation was maintained below 1.0 dB with maximum gain 15 dB and noise figure less 7 dB at pump power of 92 mW. Equalization with gain variation less than 2.0 dB can be obtained over a 12 nm wavelength range. A dual stage configuration has an added advantage where it is possible to achieve both high gain and low NF.
{"title":"Flattened dual-stage GC-EDFA using fiber-ring laser technique","authors":"M. Mas Izyani, A. Asmahanim, M. Romli","doi":"10.1109/APCC.2003.1274335","DOIUrl":"https://doi.org/10.1109/APCC.2003.1274335","url":null,"abstract":"A counter-propagating ring-laser cavity technique was demonstrated for gain-clamped and flattened erbium doped fiber amplifier. This technique was achieved by incorporating fiber Bragg grating at center wavelength 1554.88 nm with reflectivity 72.01%. A gain variation was maintained below 1.0 dB with maximum gain 15 dB and noise figure less 7 dB at pump power of 92 mW. Equalization with gain variation less than 2.0 dB can be obtained over a 12 nm wavelength range. A dual stage configuration has an added advantage where it is possible to achieve both high gain and low NF.","PeriodicalId":277507,"journal":{"name":"9th Asia-Pacific Conference on Communications (IEEE Cat. No.03EX732)","volume":"489 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133305235","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 : 2003-09-21DOI: 10.1109/APCC.2003.1274467
S. Chaimool, S. Kerdsumang, P. Akkaraekthalin
This paper proposes a new four-pole bandpass filter based on the triangular open-loop resonators structure. The full-wave simulator IE3D has been employed for designing the resonators, and calculating the related coupling coefficients of each resonator pair. The proposed filter circuit has been then finally constructed. It has been found that experimental results of the filter agree very well with simulation expectation. This filter also provides an improved selectivity characteristic with narrow bandwidth and compact size compared with the conventional resonator filters.
{"title":"A novel microstrip bandpass filter using triangular open-loop resonators","authors":"S. Chaimool, S. Kerdsumang, P. Akkaraekthalin","doi":"10.1109/APCC.2003.1274467","DOIUrl":"https://doi.org/10.1109/APCC.2003.1274467","url":null,"abstract":"This paper proposes a new four-pole bandpass filter based on the triangular open-loop resonators structure. The full-wave simulator IE3D has been employed for designing the resonators, and calculating the related coupling coefficients of each resonator pair. The proposed filter circuit has been then finally constructed. It has been found that experimental results of the filter agree very well with simulation expectation. This filter also provides an improved selectivity characteristic with narrow bandwidth and compact size compared with the conventional resonator filters.","PeriodicalId":277507,"journal":{"name":"9th Asia-Pacific Conference on Communications (IEEE Cat. No.03EX732)","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131696718","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 : 2003-09-21DOI: 10.1109/APCC.2003.1274265
T. Chattopadhyay, S. Chattopadhyay
This paper presents the theory and experiment of a hybrid microwave FM discriminator that operates on the combined principles of an active and a passive microwave discriminator. This discriminator implemented from passive waveguide components and a Gunn oscillator is found to have a bandwidth equal to the lockband of the Gunn oscillator and frequency sensitivity greater than that of an active discriminator. The overall figure of merit of this discriminator is greater than that of a passive and an active microwave discriminator.
{"title":"A new microwave discriminator","authors":"T. Chattopadhyay, S. Chattopadhyay","doi":"10.1109/APCC.2003.1274265","DOIUrl":"https://doi.org/10.1109/APCC.2003.1274265","url":null,"abstract":"This paper presents the theory and experiment of a hybrid microwave FM discriminator that operates on the combined principles of an active and a passive microwave discriminator. This discriminator implemented from passive waveguide components and a Gunn oscillator is found to have a bandwidth equal to the lockband of the Gunn oscillator and frequency sensitivity greater than that of an active discriminator. The overall figure of merit of this discriminator is greater than that of a passive and an active microwave discriminator.","PeriodicalId":277507,"journal":{"name":"9th Asia-Pacific Conference on Communications (IEEE Cat. No.03EX732)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121379429","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 : 2003-09-21DOI: 10.1109/APCC.2003.1274315
H. Hoang, M. Jonsson
This paper presents work on a switched Ethernet network extended to allow for periodic real-time traffic, using earliest deadline first (EDF) scheduling. A scheme of asymmetrically dividing deadlines of real-time channels between the in and outgoing links to/from the switch is proposed (ADPS). The scheme is compared with the simpler approach of dividing the deadlines in two (SDPS). The results of several software simulations of setting up RT channels over a full-duplex switched Ethernet network are presented. The simulations show that the ADPS performs better than the SDPS when master-slave communication is assumed over the network.
{"title":"Switched real-time Ethernet in industrial applications - deadline partitioning","authors":"H. Hoang, M. Jonsson","doi":"10.1109/APCC.2003.1274315","DOIUrl":"https://doi.org/10.1109/APCC.2003.1274315","url":null,"abstract":"This paper presents work on a switched Ethernet network extended to allow for periodic real-time traffic, using earliest deadline first (EDF) scheduling. A scheme of asymmetrically dividing deadlines of real-time channels between the in and outgoing links to/from the switch is proposed (ADPS). The scheme is compared with the simpler approach of dividing the deadlines in two (SDPS). The results of several software simulations of setting up RT channels over a full-duplex switched Ethernet network are presented. The simulations show that the ADPS performs better than the SDPS when master-slave communication is assumed over the network.","PeriodicalId":277507,"journal":{"name":"9th Asia-Pacific Conference on Communications (IEEE Cat. No.03EX732)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128684787","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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