Pub Date : 2004-04-19DOI: 10.1109/CCNC.2004.1286946
H. Kalva
The H.264 video coding standard has recently been standardized under the auspices of both the ITU and the ISO video experts groups. This new generation video standard, with its significant bandwidth savings, is expected to replace the use of MPEG-2 video compression in digital video systems. The complete migration to the new video coding algorithm will take several years given the wide scale use of MPEG-2 in the market place today. This creates an important need for transcoding technologies that transcode the widely available MPEG-2 compressed video to H.264 compressed format and vice versa. The high transcoding complexity can be reduced by reusing the information gathered in the video decoding process. However, given the significant differences between the MPEG-2 and the H.264 coding algorithms, transcoding is much more complex compared to MPEG-2 to MPEG-4 transcoding. We give a brief introduction to H.264 and discuss the issues in transcoding and complexity reduction.
{"title":"Issues in H.264/MPEG-2 video transcoding","authors":"H. Kalva","doi":"10.1109/CCNC.2004.1286946","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286946","url":null,"abstract":"The H.264 video coding standard has recently been standardized under the auspices of both the ITU and the ISO video experts groups. This new generation video standard, with its significant bandwidth savings, is expected to replace the use of MPEG-2 video compression in digital video systems. The complete migration to the new video coding algorithm will take several years given the wide scale use of MPEG-2 in the market place today. This creates an important need for transcoding technologies that transcode the widely available MPEG-2 compressed video to H.264 compressed format and vice versa. The high transcoding complexity can be reduced by reusing the information gathered in the video decoding process. However, given the significant differences between the MPEG-2 and the H.264 coding algorithms, transcoding is much more complex compared to MPEG-2 to MPEG-4 transcoding. We give a brief introduction to H.264 and discuss the issues in transcoding and complexity reduction.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"11 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":"125692813","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.2004.1286932
Hidekuni Ogawa, H. Maki, Ishio Ninomiya, Y. Yonezawa, Haruhiko Sato, W. Caldwell
In Japan, hospital or welfare office home helpers provide home welfare and care services, such as cooking, bathing, washing, cleaning and shopping, for the elderly. We have developed a Web-based home welfare and care services request system using wireless Internet mobile phones and Internet client computers; it employs a pen type image sensor for the elderly people to enter their handwritten care requests. The client computer sends the requests to the server computer in the home helper central office, and then the server computer automatically transfers them to the home helper's mobile phone. This newly-developed home welfare and care services request system is easily operated by elderly persons.
{"title":"A Web-based home welfare and care services request system using a pen type image sensor","authors":"Hidekuni Ogawa, H. Maki, Ishio Ninomiya, Y. Yonezawa, Haruhiko Sato, W. Caldwell","doi":"10.1109/CCNC.2004.1286932","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286932","url":null,"abstract":"In Japan, hospital or welfare office home helpers provide home welfare and care services, such as cooking, bathing, washing, cleaning and shopping, for the elderly. We have developed a Web-based home welfare and care services request system using wireless Internet mobile phones and Internet client computers; it employs a pen type image sensor for the elderly people to enter their handwritten care requests. The client computer sends the requests to the server computer in the home helper central office, and then the server computer automatically transfers them to the home helper's mobile phone. This newly-developed home welfare and care services request system is easily operated by elderly persons.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"80 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":"130695197","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.2004.1286902
Bo Yan, Kam-Wing Ng
Video transmission over error-prone channels requires techniques that are efficient in compressing the video and robust against the channel errors. The application of MPEG-4 in video communication can conform to bandwidth limitations, but, on the other hand, the highly compressed bits are more susceptible to noise errors. Therefore, many researchers have been working on error concealment techniques to recover errors caused by noise. However, the errors are always assumed to have been correctly located, which is the precondition for error concealment. We propose a novel error detection technique. This scheme can effectively and efficiently detect some errors which cannot be detected traditionally. Experimental results show that the error detection ratio (EDR) for this type of error is more than 90%, even 100% sometimes.
{"title":"An efficient error detection technique for MPEG-4 video streams","authors":"Bo Yan, Kam-Wing Ng","doi":"10.1109/CCNC.2004.1286902","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286902","url":null,"abstract":"Video transmission over error-prone channels requires techniques that are efficient in compressing the video and robust against the channel errors. The application of MPEG-4 in video communication can conform to bandwidth limitations, but, on the other hand, the highly compressed bits are more susceptible to noise errors. Therefore, many researchers have been working on error concealment techniques to recover errors caused by noise. However, the errors are always assumed to have been correctly located, which is the precondition for error concealment. We propose a novel error detection technique. This scheme can effectively and efficiently detect some errors which cannot be detected traditionally. Experimental results show that the error detection ratio (EDR) for this type of error is more than 90%, even 100% sometimes.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"227 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":"132063530","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.2004.1286824
Chaiwat Oottamakorn, Dennis Bushmitch
We propose and evaluate a resource management and scheduling algorithm for a quality of service (QoS)-aware wireless access router for use in enterprise and home network solutions. The proposed algorithm provides delay and packet loss service guarantees to a diverse set of application traffic classes, produced as a result of convergence of home entertainment and data networks. The algorithm provides both relative and absolute (where applicable) QoS guarantees to traffic classes. One of the key results of our work is the development of an efficient procedure for capturing the predictive traffic characteristics and performances by monitoring ongoing traffic arrivals. This allows the wireless router's resource management while determining sufficient service rate for each traffic class in order to meet its QoS requirements. Key features of the algorithm are its scalable implementation and the effectiveness of QoS controls it extends. We also present the simulation results, which demonstrate algorithm's efficiency in handling the variety of real-time data.
{"title":"Resource management and scheduling for the QoS-capable home network wireless access point","authors":"Chaiwat Oottamakorn, Dennis Bushmitch","doi":"10.1109/CCNC.2004.1286824","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286824","url":null,"abstract":"We propose and evaluate a resource management and scheduling algorithm for a quality of service (QoS)-aware wireless access router for use in enterprise and home network solutions. The proposed algorithm provides delay and packet loss service guarantees to a diverse set of application traffic classes, produced as a result of convergence of home entertainment and data networks. The algorithm provides both relative and absolute (where applicable) QoS guarantees to traffic classes. One of the key results of our work is the development of an efficient procedure for capturing the predictive traffic characteristics and performances by monitoring ongoing traffic arrivals. This allows the wireless router's resource management while determining sufficient service rate for each traffic class in order to meet its QoS requirements. Key features of the algorithm are its scalable implementation and the effectiveness of QoS controls it extends. We also present the simulation results, which demonstrate algorithm's efficiency in handling the variety of real-time data.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"35 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":"126463686","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.2004.1286857
Timuçin Özugur, B. Sarikaya
We design a methodology for fast IPv4 and IPv6 address acquisition by mobile layer-2 entities in a wireless LAN. The main idea is to do the IP address assignment whenever it is necessary, not after the mobile establishes a layer-2 connection with a new access point. In order to achieve this, we propose to encapsulate the current IP address of the mobile to the association or re-association message in 802.11 WLANs. We present procedures of address acquisition for IPv4, IPv6 and Mobile IPv4, Mobile IPv6. Due to the hidden station problem, the mobile cannot successfully achieve the duplicate address detection (DAD) procedure in IPv6. Our proposal does not require the DAD, so the impact of the hidden station problem in IPv6 address assignment is eliminated. The proposed address assignment procedure, which is executed with layer-2 association, is faster than the existing DHCP-based stateful IP assignment.
{"title":"Fast IPv4/IPv6 address acquisition in wireless LANs","authors":"Timuçin Özugur, B. Sarikaya","doi":"10.1109/CCNC.2004.1286857","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286857","url":null,"abstract":"We design a methodology for fast IPv4 and IPv6 address acquisition by mobile layer-2 entities in a wireless LAN. The main idea is to do the IP address assignment whenever it is necessary, not after the mobile establishes a layer-2 connection with a new access point. In order to achieve this, we propose to encapsulate the current IP address of the mobile to the association or re-association message in 802.11 WLANs. We present procedures of address acquisition for IPv4, IPv6 and Mobile IPv4, Mobile IPv6. Due to the hidden station problem, the mobile cannot successfully achieve the duplicate address detection (DAD) procedure in IPv6. Our proposal does not require the DAD, so the impact of the hidden station problem in IPv6 address assignment is eliminated. The proposed address assignment procedure, which is executed with layer-2 association, is faster than the existing DHCP-based stateful IP assignment.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"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":"120956240","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.2004.1286899
T. Senoh, Takafumi Ueno, T. Kogure, Shengmei Shen, Ming Ji, Jing Liu, Zhongyang Huang, Craig A. Schultz
Current digital rights management systems employ proprietary methods to protect contents. Hence, they are incapable of interoperation with each other. This causes great inconvenience for users who want to subscribe to contents from different providers. We introduce a new, intellectual property management & protection method (IPMP extension), which enables users to enjoy content services delivered from different providers which are based on individual content protection mechanisms. The method is proposed to ISO/IEC JTC1/SC29/WG11 (MPEG) and the standardization is in the final stage. IPMP is also proposed to DVB-CPT (digital video broadcasting-copy protection technologies). TV Anytime Forum ISMA (Internet Streaming Media Alliance) have adopted IPMP in the ISMA1.0 Encryption & Authentication specification.
{"title":"DRM renewability & interoperability","authors":"T. Senoh, Takafumi Ueno, T. Kogure, Shengmei Shen, Ming Ji, Jing Liu, Zhongyang Huang, Craig A. Schultz","doi":"10.1109/CCNC.2004.1286899","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286899","url":null,"abstract":"Current digital rights management systems employ proprietary methods to protect contents. Hence, they are incapable of interoperation with each other. This causes great inconvenience for users who want to subscribe to contents from different providers. We introduce a new, intellectual property management & protection method (IPMP extension), which enables users to enjoy content services delivered from different providers which are based on individual content protection mechanisms. The method is proposed to ISO/IEC JTC1/SC29/WG11 (MPEG) and the standardization is in the final stage. IPMP is also proposed to DVB-CPT (digital video broadcasting-copy protection technologies). TV Anytime Forum ISMA (Internet Streaming Media Alliance) have adopted IPMP in the ISMA1.0 Encryption & Authentication specification.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"31 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":"121821724","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.2004.1286909
A. Thawani, S. Gopalan, V. Sridhar
The growth in digital TV penetration has resulted in an enormous research initiative in community-specific and home/user-specific target advertising. We propose a channel surfing analysis (CSA) algorithm for predicting the "user(s) in front" of TV by a dynamic analysis of channel viewing characteristics. Such a user identification can be used along with a home information system to decide categorically about the nature of advertisements that are likely to have an impact. The proposed CSA algorithm uses a time-based FSM representation of channel viewing (remote usage) patterns that can be analyzed and processed in multiple ways leading to sophisticated algorithms. Taking into account the fact that not all channel switches provide equal cues about user characteristics, we suggest a multiscale approach to analyze the FSM at various levels of abstraction. We are in the process of integrating the CSA algorithm with an MHP (multimedia home platform) based interactive TV platform that is currently under development.
{"title":"Viewing characteristics based personalized ad streaming in an interactive TV environment","authors":"A. Thawani, S. Gopalan, V. Sridhar","doi":"10.1109/CCNC.2004.1286909","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286909","url":null,"abstract":"The growth in digital TV penetration has resulted in an enormous research initiative in community-specific and home/user-specific target advertising. We propose a channel surfing analysis (CSA) algorithm for predicting the \"user(s) in front\" of TV by a dynamic analysis of channel viewing characteristics. Such a user identification can be used along with a home information system to decide categorically about the nature of advertisements that are likely to have an impact. The proposed CSA algorithm uses a time-based FSM representation of channel viewing (remote usage) patterns that can be analyzed and processed in multiple ways leading to sophisticated algorithms. Taking into account the fact that not all channel switches provide equal cues about user characteristics, we suggest a multiscale approach to analyze the FSM at various levels of abstraction. We are in the process of integrating the CSA algorithm with an MHP (multimedia home platform) based interactive TV platform that is currently under development.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"81 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":"124894343","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}
Audio/video (AV) devices capable of IP communications over Ethernet are evolving into ubiquitous network home appliances. However, cabling an Ethernet network in existing dwellings is a difficult challenge that hinders their popularization. To overcome this obstacle, we have focused our attention on high-speed power line communications technology, which enables 100Base-T class IP networking using existing power lines as the communication medium. However, power line channel characteristics are fairly unstable and it is very difficult to provide stable transport of mixed streams (such as video contents, voice-over-IP, audio and data transfers) requiring different communication quality. We propose a real time error handling technique to alleviate the effects of errors by quickly responding to changes in power line channel characteristics and a MAC (media access control) technique to guarantee the transmission of buffered data using intelligent TDMA (time division multiple access). Through simulation results, we verify that the proposed techniques achieve stable AV stream transport.
{"title":"A media access control method for high-speed power line communication system modems","authors":"Shinichiro Ohmi, Shigeo Yoshida, Tsuyoshi Yamaguchi, Gou Kuroda","doi":"10.1109/CCNC.2004.1286875","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286875","url":null,"abstract":"Audio/video (AV) devices capable of IP communications over Ethernet are evolving into ubiquitous network home appliances. However, cabling an Ethernet network in existing dwellings is a difficult challenge that hinders their popularization. To overcome this obstacle, we have focused our attention on high-speed power line communications technology, which enables 100Base-T class IP networking using existing power lines as the communication medium. However, power line channel characteristics are fairly unstable and it is very difficult to provide stable transport of mixed streams (such as video contents, voice-over-IP, audio and data transfers) requiring different communication quality. We propose a real time error handling technique to alleviate the effects of errors by quickly responding to changes in power line channel characteristics and a MAC (media access control) technique to guarantee the transmission of buffered data using intelligent TDMA (time division multiple access). Through simulation results, we verify that the proposed techniques achieve stable AV stream transport.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"10 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":"131502601","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.2004.1286933
C. Ngo
Using a service-oriented approach, we determined the services and the ultimate end-equipment needed in each room of a home. We found that future homes could be very simple without many "electronic boxes" as of today. We believe that future home networking will focus just on the distribution of needed services to the ultimate end-equipment via a simple, yet smart, flexible and reliable, home network. Hence, we proposed a semi-decentralized home network architecture which consisted of a home media server and a number of "room-servers". "Room services" in each room were provided via its corresponding "room-server". In order to provide neat and simple services to consumers, an all-wireless solution was further proposed using the upcoming IEEE 802.15.3a and IEEE 802.11n standards.
{"title":"A service-oriented wireless home network","authors":"C. Ngo","doi":"10.1109/CCNC.2004.1286933","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286933","url":null,"abstract":"Using a service-oriented approach, we determined the services and the ultimate end-equipment needed in each room of a home. We found that future homes could be very simple without many \"electronic boxes\" as of today. We believe that future home networking will focus just on the distribution of needed services to the ultimate end-equipment via a simple, yet smart, flexible and reliable, home network. Hence, we proposed a semi-decentralized home network architecture which consisted of a home media server and a number of \"room-servers\". \"Room services\" in each room were provided via its corresponding \"room-server\". In order to provide neat and simple services to consumers, an all-wireless solution was further proposed using the upcoming IEEE 802.15.3a and IEEE 802.11n standards.","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":"134201105","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.2004.1286831
Arno Wacker, Timo Heiber, Holger Cermann
Wireless home automation networks are one example of how wireless technologies may soon become part of our daily life, yet security in existing products is woefully inadequate. An important problem in this area is the question of secure key distribution. We present a key-distribution scheme geared towards home automation networks, but also applicable to other networks with related properties. Our approach uses a decentralized scheme that is designed to work on resource-poor devices, allows easy addition and removal of devices and limits the workload on the end user while guaranteeing the secrecy of the exchanged keys even in the presence of subverted nodes.
{"title":"A key-distribution scheme for wireless home automation networks","authors":"Arno Wacker, Timo Heiber, Holger Cermann","doi":"10.1109/CCNC.2004.1286831","DOIUrl":"https://doi.org/10.1109/CCNC.2004.1286831","url":null,"abstract":"Wireless home automation networks are one example of how wireless technologies may soon become part of our daily life, yet security in existing products is woefully inadequate. An important problem in this area is the question of secure key distribution. We present a key-distribution scheme geared towards home automation networks, but also applicable to other networks with related properties. Our approach uses a decentralized scheme that is designed to work on resource-poor devices, allows easy addition and removal of devices and limits the workload on the end user while guaranteeing the secrecy of the exchanged keys even in the presence of subverted nodes.","PeriodicalId":316094,"journal":{"name":"First IEEE Consumer Communications and Networking Conference, 2004. CCNC 2004.","volume":"15 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":"116070761","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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