Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4391996
Jian Zhu, Jinchun Gao, G. Xie, Yuan'an Liu
Based on finite element method (FEM), the impact of coaxial connection failure on high speed signal transmission was researched. The contact resistance, contact inductance and interfacial capacitance were calculated at high frequencies. According to the improved model of contact impedance, the influence on high speed signal transmission was analyzed. Experiment was taken to measure the DC contact resistance and high frequency impedance of some degraded BNC coaxial connectors. The impact of connection failure on E2 data transmission was also observed in the experiment. Some important conclusion was summarized to explain the malfunction in communication system due to the contact failure.
{"title":"FEM analysis of the impact of coaxial connector on high speed signal transmission","authors":"Jian Zhu, Jinchun Gao, G. Xie, Yuan'an Liu","doi":"10.1109/ISCIT.2007.4391996","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4391996","url":null,"abstract":"Based on finite element method (FEM), the impact of coaxial connection failure on high speed signal transmission was researched. The contact resistance, contact inductance and interfacial capacitance were calculated at high frequencies. According to the improved model of contact impedance, the influence on high speed signal transmission was analyzed. Experiment was taken to measure the DC contact resistance and high frequency impedance of some degraded BNC coaxial connectors. The impact of connection failure on E2 data transmission was also observed in the experiment. Some important conclusion was summarized to explain the malfunction in communication system due to the contact failure.","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":"117133031","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.2007.4391985
M.A.G. Lorenzo, A. Manzano, M. Gusad, J. Hizon, M. Rosales
The paper presents the design and implementation of six operational amplifiers with rail-to-rail input and output capability. The study characterizes several rail-to-rail input and output stages and the dependence of the op-amp's operation on different design parameters to formulate a standard design methodology that can serve as a guide for future researches and projects in the area of rail-to-rail amplifiers. The report shows the effects of the rail-to-rail stages on the op-amp's input common-mode range and output voltage swing range. The op-amps are implemented in 0.25 mum CMOS process and the simulation results achieve specifications such as gain, bandwidth, offset voltages and common-mode rejection ratio comparable with commercially available circuits.
本文介绍了六种具有轨对轨输入输出能力的运算放大器的设计与实现。该研究描述了几个轨对轨输入和输出阶段，以及运算放大器的运行对不同设计参数的依赖关系，以制定一个标准的设计方法，可以作为轨对轨放大器领域未来研究和项目的指导。该报告显示了轨对轨级对运放输入共模范围和输出电压摆幅范围的影响。运算放大器采用0.25 μ m CMOS工艺实现，仿真结果达到了与市售电路相当的增益、带宽、失调电压和共模抑制比等规格。
{"title":"Design and implementation of CMOS rail-to-rail operational amplifiers","authors":"M.A.G. Lorenzo, A. Manzano, M. Gusad, J. Hizon, M. Rosales","doi":"10.1109/ISCIT.2007.4391985","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4391985","url":null,"abstract":"The paper presents the design and implementation of six operational amplifiers with rail-to-rail input and output capability. The study characterizes several rail-to-rail input and output stages and the dependence of the op-amp's operation on different design parameters to formulate a standard design methodology that can serve as a guide for future researches and projects in the area of rail-to-rail amplifiers. The report shows the effects of the rail-to-rail stages on the op-amp's input common-mode range and output voltage swing range. The op-amps are implemented in 0.25 mum CMOS process and the simulation results achieve specifications such as gain, bandwidth, offset voltages and common-mode rejection ratio comparable with commercially available circuits.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"3 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":"116158554","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.2007.4392055
Lan Wang, Daqing Gu
The IMS-based, half-duplex push-to-talk over cellular (PoC) service provides a cost-efficient, interactive, and global-reach service for group and individual communications. The media types for PoC users can be voice, video, images, and text messages. Presence service is widely used and is often bundled with PoC and instant messaging (IM) to indicate other users' availability and willingness of communications. In this paper, we investigate the session setup procedure for the PoC group communications within OMA PoC infrastructure and propose a method to optimize the initiation of a PoC prearranged group session using rich presence information. With this method, the SIP signaling traffic and session delay are significantly reduced.
{"title":"A study on session setup for group communications in push-to-talk over cellular using rich presence","authors":"Lan Wang, Daqing Gu","doi":"10.1109/ISCIT.2007.4392055","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392055","url":null,"abstract":"The IMS-based, half-duplex push-to-talk over cellular (PoC) service provides a cost-efficient, interactive, and global-reach service for group and individual communications. The media types for PoC users can be voice, video, images, and text messages. Presence service is widely used and is often bundled with PoC and instant messaging (IM) to indicate other users' availability and willingness of communications. In this paper, we investigate the session setup procedure for the PoC group communications within OMA PoC infrastructure and propose a method to optimize the initiation of a PoC prearranged group session using rich presence information. With this method, the SIP signaling traffic and session delay are significantly reduced.","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":"115165386","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.2007.4392079
Tan Li, R. Zhang, R. Yang, Heyun Huang, Fuhuei Lin
MDCT/IMDCT has been widely adopted to transform an audio sequence from time domain to transform domain by various audio codec standards. This paper presents a unified algorithm and its hardware design for cosine modulated filter bank. In algorithm derivation, both MDCT and IMDCT are first converted to a half size DCT-IV with input or output permutation. The DCT-IV is then realized by a fast DCT-II algorithm. Both radix-3 and radix-2 DCT-II algorithms are analyzed and a unified computing kernel is concluded.
{"title":"A unified computing kernel for MDCT/IMDCT in modern audio coding standards","authors":"Tan Li, R. Zhang, R. Yang, Heyun Huang, Fuhuei Lin","doi":"10.1109/ISCIT.2007.4392079","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392079","url":null,"abstract":"MDCT/IMDCT has been widely adopted to transform an audio sequence from time domain to transform domain by various audio codec standards. This paper presents a unified algorithm and its hardware design for cosine modulated filter bank. In algorithm derivation, both MDCT and IMDCT are first converted to a half size DCT-IV with input or output permutation. The DCT-IV is then realized by a fast DCT-II algorithm. Both radix-3 and radix-2 DCT-II algorithms are analyzed and a unified computing kernel is concluded.","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":"123361502","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.2007.4392029
J. DasGupta, K. Ziri-Castro, H. Suzuki
This paper presents the results of dynamic channel capacity measurements for a multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system in two populated indoor environments with and without line-of-sight (LoS). The experiment used 4 sending and 4 receiving antennas and 114 sub-carriers at 5 GHz as per draft IEEE 802.11n. MIMO-OFDM channel capacity is analysed both with fixed receiver signal-to-noise ratio (SNR) and fixed transmitter (Tx) power criteria. It is found that fixed SNR capacity increased while fixed Tx power capacity decreased in both environments by the presence of pedestrian. It is also revealed that the spread of the capacity cumulative distribution function (CDF) increased due to the pedestrians in both environments with both criteria.
{"title":"Capacity analysis of MIMO-OFDM broadband channels in populated indoor environments","authors":"J. DasGupta, K. Ziri-Castro, H. Suzuki","doi":"10.1109/ISCIT.2007.4392029","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392029","url":null,"abstract":"This paper presents the results of dynamic channel capacity measurements for a multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system in two populated indoor environments with and without line-of-sight (LoS). The experiment used 4 sending and 4 receiving antennas and 114 sub-carriers at 5 GHz as per draft IEEE 802.11n. MIMO-OFDM channel capacity is analysed both with fixed receiver signal-to-noise ratio (SNR) and fixed transmitter (Tx) power criteria. It is found that fixed SNR capacity increased while fixed Tx power capacity decreased in both environments by the presence of pedestrian. It is also revealed that the spread of the capacity cumulative distribution function (CDF) increased due to the pedestrians in both environments with both criteria.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"45 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":"123117063","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.2007.4392135
J.C.-P. Wang, M. Abolhasan, F. Safaei, D. Franklin
The rapid diminishing in the cost of commodity wireless hardware in recent years has prompted the use of multiple radios to improve the capacity of wireless networks. However, the research has shown that the improvement obtained from using multiple radios does not solely depend on the number of radios, but primarily on how these radios can be integrated in a constructive manner. A common way of integration multiple radios is to use a dedicated radio for control. To date, a number of multi-radio MAC protocol are employing a dedicated radio to control and coordinate the other radios, though the approaches are varied from one to another. In this paper, the control separation techniques in the multi-radio multi-channel MAC have been surveyed, and a classification of control separation techniques is provided. Moreover, this study points out the open research issues and intends to spark new interests and developments in this field.
{"title":"A survey on control separation techniques in multi-radio multi-channel MAC protocols","authors":"J.C.-P. Wang, M. Abolhasan, F. Safaei, D. Franklin","doi":"10.1109/ISCIT.2007.4392135","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392135","url":null,"abstract":"The rapid diminishing in the cost of commodity wireless hardware in recent years has prompted the use of multiple radios to improve the capacity of wireless networks. However, the research has shown that the improvement obtained from using multiple radios does not solely depend on the number of radios, but primarily on how these radios can be integrated in a constructive manner. A common way of integration multiple radios is to use a dedicated radio for control. To date, a number of multi-radio MAC protocol are employing a dedicated radio to control and coordinate the other radios, though the approaches are varied from one to another. In this paper, the control separation techniques in the multi-radio multi-channel MAC have been surveyed, and a classification of control separation techniques is provided. Moreover, this study points out the open research issues and intends to spark new interests and developments in this field.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"43 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":"122158580","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.2007.4391995
Seokjin Kim, M. Peckerar
High-speed analog-to-digital converter using on-chip digital de-multiplexing and clock distribution is presented with detail sequences of operation for dynamic performance testing. Digital outputs are post processed and fed into a computer-aided ADC performance characterization tool. The problems of high sampling rate ADC testing are described. The test methodologies described reduce test costs and overcome many test hardware limitations. As our focus is on satellite receiver systems, we emphasize the measurement of inter-modulation distortion and effective resolution bandwidth. As a primary characterization component, Fourier analysis is used and we address the issue of sample window adjustment to eliminate spectral leakage and false spur generation. A 6-bit 800 MSa/s dual channel SiGe-based ADC from Hughes network systems is used as a target example.
{"title":"High speed analog-to-digital converter design verification tests in satellite receivers","authors":"Seokjin Kim, M. Peckerar","doi":"10.1109/ISCIT.2007.4391995","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4391995","url":null,"abstract":"High-speed analog-to-digital converter using on-chip digital de-multiplexing and clock distribution is presented with detail sequences of operation for dynamic performance testing. Digital outputs are post processed and fed into a computer-aided ADC performance characterization tool. The problems of high sampling rate ADC testing are described. The test methodologies described reduce test costs and overcome many test hardware limitations. As our focus is on satellite receiver systems, we emphasize the measurement of inter-modulation distortion and effective resolution bandwidth. As a primary characterization component, Fourier analysis is used and we address the issue of sample window adjustment to eliminate spectral leakage and false spur generation. A 6-bit 800 MSa/s dual channel SiGe-based ADC from Hughes network systems is used as a target example.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"136 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":"122750587","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}
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}
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