Pub Date : 2008-11-01DOI: 10.1109/HONET.2008.4810235
Dat Tien Nguyen, B. Soh
Key management using threshold cryptography has proved its advantages by eliminating the dependence on an online central authority. However, some previous models are not suitable due to the inflexibility in dealing with keys. Moreover, solutions for those models are not complete; there are still vulnerabilities for attacks, especially DoS attacks. This paper will propose a more flexible modified key management scheme and a tolerant solution to reduce the attack risk. Our model will allow mobile nodes to generate their session keys instead of being associated with a fixed key in their whole lifetime. Besides, we propose using threshold cryptography to authenticate exchanged messages in an authentication process. Our solution can be shown to overcome the weaknesses of the existing algorithms.
{"title":"Enhancing the certificate service in Ad-hoc Networks","authors":"Dat Tien Nguyen, B. Soh","doi":"10.1109/HONET.2008.4810235","DOIUrl":"https://doi.org/10.1109/HONET.2008.4810235","url":null,"abstract":"Key management using threshold cryptography has proved its advantages by eliminating the dependence on an online central authority. However, some previous models are not suitable due to the inflexibility in dealing with keys. Moreover, solutions for those models are not complete; there are still vulnerabilities for attacks, especially DoS attacks. This paper will propose a more flexible modified key management scheme and a tolerant solution to reduce the attack risk. Our model will allow mobile nodes to generate their session keys instead of being associated with a fixed key in their whole lifetime. Besides, we propose using threshold cryptography to authenticate exchanged messages in an authentication process. Our solution can be shown to overcome the weaknesses of the existing algorithms.","PeriodicalId":433243,"journal":{"name":"2008 International Symposium on High Capacity Optical Networks and Enabling Technologies","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134406469","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 : 2008-11-01DOI: 10.1109/HONET.2008.4810244
G. Gnanagurunathan, H. Dias
We have analysed the performance of three different modulation schemes for an ultra high spectral efficient, dense wavelength division multiplexing whereby with a channel spacing of 50 GHz. Two Dispersion Management Schemes (DMS), namely, DCF (Dispersion Compensated Fiber) and FBG (Fiber Bragg Grating) were integrated into the link and their performance were observed in terms of BER. Besides the standard modulation scheme of Non Return to Zero and Return to Zero, we have compared the performance of Duobinary modulation with both these DMS. The traffic loads and modulation schemes were varied to identify the dependence if any on one another. Conclusively, it is observed that the dispersion tolerant NRZ and the advanced modulation scheme, Duobinary perform well with FBG whereas modulation schemes RZ performs best with DCF in a narrowband short haul link.
{"title":"Analyzing the RZ, NRZ and DB in a DCF and FBG Compensated Narrowband Short Haul Optical Link","authors":"G. Gnanagurunathan, H. Dias","doi":"10.1109/HONET.2008.4810244","DOIUrl":"https://doi.org/10.1109/HONET.2008.4810244","url":null,"abstract":"We have analysed the performance of three different modulation schemes for an ultra high spectral efficient, dense wavelength division multiplexing whereby with a channel spacing of 50 GHz. Two Dispersion Management Schemes (DMS), namely, DCF (Dispersion Compensated Fiber) and FBG (Fiber Bragg Grating) were integrated into the link and their performance were observed in terms of BER. Besides the standard modulation scheme of Non Return to Zero and Return to Zero, we have compared the performance of Duobinary modulation with both these DMS. The traffic loads and modulation schemes were varied to identify the dependence if any on one another. Conclusively, it is observed that the dispersion tolerant NRZ and the advanced modulation scheme, Duobinary perform well with FBG whereas modulation schemes RZ performs best with DCF in a narrowband short haul link.","PeriodicalId":433243,"journal":{"name":"2008 International Symposium on High Capacity Optical Networks and Enabling Technologies","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124240795","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 : 2008-11-01DOI: 10.1109/HONET.2008.4810240
M. Ali, W. Mardini, Yaser Akbar, Ghaffar Pour, Rahbar Khamayseh
The increasing demand of various networking applications such as Internet, voice, data, video and TV services inside large cities with large population requires the design and implementation of more effective metropolitan networks. Currently, several wireless networking systems were established to provide such services. Two main fixed broadband access network were used for such services: Local Multipoint Distribution Service (LMDS) and Multi-channel Multipoint Distribution Service (MMDS). Both of these systems face several problems such as: high cost, relatively low speed, small coverage area, and last-mile bottleneck. The effect of the above mentioned problems are more obvious when the network size increases. The deployment of a new technology by using Wireless Optical Mesh Network (WOMN), which use wireless optical communications between nodes, can overcome these problems and can provide more bandwidth, interference-free, frequency-free and more effectiveness in applications that require a real time responding like video surveillance. We investigate the WOMN advantages and disadvantages. We also discuss the commercial, geographical coverage and real time applicability. We will also investigate the challenges to deploy the new technique for local and metropolitan networks between different city buildings.
{"title":"Improvements of using the WOMN System in Communication","authors":"M. Ali, W. Mardini, Yaser Akbar, Ghaffar Pour, Rahbar Khamayseh","doi":"10.1109/HONET.2008.4810240","DOIUrl":"https://doi.org/10.1109/HONET.2008.4810240","url":null,"abstract":"The increasing demand of various networking applications such as Internet, voice, data, video and TV services inside large cities with large population requires the design and implementation of more effective metropolitan networks. Currently, several wireless networking systems were established to provide such services. Two main fixed broadband access network were used for such services: Local Multipoint Distribution Service (LMDS) and Multi-channel Multipoint Distribution Service (MMDS). Both of these systems face several problems such as: high cost, relatively low speed, small coverage area, and last-mile bottleneck. The effect of the above mentioned problems are more obvious when the network size increases. The deployment of a new technology by using Wireless Optical Mesh Network (WOMN), which use wireless optical communications between nodes, can overcome these problems and can provide more bandwidth, interference-free, frequency-free and more effectiveness in applications that require a real time responding like video surveillance. We investigate the WOMN advantages and disadvantages. We also discuss the commercial, geographical coverage and real time applicability. We will also investigate the challenges to deploy the new technique for local and metropolitan networks between different city buildings.","PeriodicalId":433243,"journal":{"name":"2008 International Symposium on High Capacity Optical Networks and Enabling Technologies","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121305403","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 : 2008-11-01DOI: 10.1109/HONET.2008.4810221
M. Mayeh, F. Farahi
Wavelength multiplexing/demultiplexing devices are considered to be one of the key elements in optical networks. Here we propose a new class of wavelength MUX/DEMUX devices which are based on change in the geometry of the multimode interference (MMI) waveguide region. This modification enables us to optimize device performances for a given set of refractive indices of core and cladding. The material of choice is SiON since it has an excellent surface morphology for the optical device application and its index of refraction can be varied from as low as 1.45 to as high as 2.5. A few designs for compact wavelength MUX/DEMUX based on off-center-fed excitement in geometrically modified MMI (GMM) are presented. Results show that modification in geometry of MMI device will lead to the better performances relative to simple MMI devices.
{"title":"Geometrically modified multimode interference waveguides using high refractive index SiON material, for application in wavelength multiplexing/demultiplexing","authors":"M. Mayeh, F. Farahi","doi":"10.1109/HONET.2008.4810221","DOIUrl":"https://doi.org/10.1109/HONET.2008.4810221","url":null,"abstract":"Wavelength multiplexing/demultiplexing devices are considered to be one of the key elements in optical networks. Here we propose a new class of wavelength MUX/DEMUX devices which are based on change in the geometry of the multimode interference (MMI) waveguide region. This modification enables us to optimize device performances for a given set of refractive indices of core and cladding. The material of choice is SiON since it has an excellent surface morphology for the optical device application and its index of refraction can be varied from as low as 1.45 to as high as 2.5. A few designs for compact wavelength MUX/DEMUX based on off-center-fed excitement in geometrically modified MMI (GMM) are presented. Results show that modification in geometry of MMI device will lead to the better performances relative to simple MMI devices.","PeriodicalId":433243,"journal":{"name":"2008 International Symposium on High Capacity Optical Networks and Enabling Technologies","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122241576","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 : 2008-11-01DOI: 10.1109/HONET.2008.4810242
K. Acharya, M. Raja
The effect of SRS crosstalk in PON has been reported in several papers. In this paper, we propose a solution that can be used to compensate the signal attenuation due to SRS crosstalk. Proposed solution can also be used to increase the reach of PON, in an effort to merge access and metro networks. This is done by using remote Raman amplification where, a CW counter-propagating pump is placed at one of the ONUs. A ~15 dB amplification of the downstream signal is observed with a BER < 10e-12.
已有多篇论文报道了SRS串扰对PON的影响。在本文中，我们提出了一种可用于补偿由于SRS串扰引起的信号衰减的解决方案。提出的解决方案还可用于增加PON的覆盖范围，以实现接入网和城域网的合并。这是通过使用远程拉曼放大来实现的，在其中一个onu上放置一个连续波反传播泵。观察到下游信号放大~ 15db, BER < 10e-12。
{"title":"Raman Amplified PON (RA-PON): mitigating SRS using SRS","authors":"K. Acharya, M. Raja","doi":"10.1109/HONET.2008.4810242","DOIUrl":"https://doi.org/10.1109/HONET.2008.4810242","url":null,"abstract":"The effect of SRS crosstalk in PON has been reported in several papers. In this paper, we propose a solution that can be used to compensate the signal attenuation due to SRS crosstalk. Proposed solution can also be used to increase the reach of PON, in an effort to merge access and metro networks. This is done by using remote Raman amplification where, a CW counter-propagating pump is placed at one of the ONUs. A ~15 dB amplification of the downstream signal is observed with a BER < 10e-12.","PeriodicalId":433243,"journal":{"name":"2008 International Symposium on High Capacity Optical Networks and Enabling Technologies","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125128735","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 : 2008-11-01DOI: 10.1109/HONET.2008.4810225
S. Mohammad-Nejad, M. Aliramezani, M. Pourmahyabadi
A novel photonic crystal fiber (PCF) structure with two different air-hole sizes is proposed. The PCF has ultra-flattened dispersion and negligible confinement loss characteristics throughout the telecommunication bands (O-band to L-band). The design strategy to achieve these properties is based on optimization of two air-hole diameters. Furthermore, the PCF has only five rings of air-holes to control dispersion and confinement loss. Furthermore, the validation of the proposed design is carried out by employing a 2-D FDFD with perfectly matched layers. Macro-bending loss performance of the designed PCF is also studied and it is found that the fiber shows low bending losses for the smallest feasible bending radius of 5 mm.
{"title":"Design of a Photonic Crystal Fiber with Improved Dispersion and Confinement Loss Over All Telecommunication Bands","authors":"S. Mohammad-Nejad, M. Aliramezani, M. Pourmahyabadi","doi":"10.1109/HONET.2008.4810225","DOIUrl":"https://doi.org/10.1109/HONET.2008.4810225","url":null,"abstract":"A novel photonic crystal fiber (PCF) structure with two different air-hole sizes is proposed. The PCF has ultra-flattened dispersion and negligible confinement loss characteristics throughout the telecommunication bands (O-band to L-band). The design strategy to achieve these properties is based on optimization of two air-hole diameters. Furthermore, the PCF has only five rings of air-holes to control dispersion and confinement loss. Furthermore, the validation of the proposed design is carried out by employing a 2-D FDFD with perfectly matched layers. Macro-bending loss performance of the designed PCF is also studied and it is found that the fiber shows low bending losses for the smallest feasible bending radius of 5 mm.","PeriodicalId":433243,"journal":{"name":"2008 International Symposium on High Capacity Optical Networks and Enabling Technologies","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126275244","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 : 2008-11-01DOI: 10.1109/HONET.2008.4810216
S. Alifah, S. M. Idrus, N. Kassim
One of the major concern for the system is the issue of noise and interference. The majority source of nonlinearity come from laser diode nonlinearity. Likewise, the linearity improvement of optical transmitter is very important to enhance system performance in term of dynamic range. This paper demonstrated the simultaneous noise reduction and linearity improvement of optical transmitter using proposed feedforward linearization scheme for radio over fiber system. The system performance is predicted based on the simulation result in term of third order intermodulation distortion (IMD3) and relative intensity noise (RIN) reduction. The results show that simultaneous reduction of IMD3 up to 33 dB and RIN up to 20 dB employing the proposed system.
{"title":"Simultaneous Noise Reduction and Linearity Improvement of Optical Feedforward Transmitter for Radio over Fiber Systems","authors":"S. Alifah, S. M. Idrus, N. Kassim","doi":"10.1109/HONET.2008.4810216","DOIUrl":"https://doi.org/10.1109/HONET.2008.4810216","url":null,"abstract":"One of the major concern for the system is the issue of noise and interference. The majority source of nonlinearity come from laser diode nonlinearity. Likewise, the linearity improvement of optical transmitter is very important to enhance system performance in term of dynamic range. This paper demonstrated the simultaneous noise reduction and linearity improvement of optical transmitter using proposed feedforward linearization scheme for radio over fiber system. The system performance is predicted based on the simulation result in term of third order intermodulation distortion (IMD3) and relative intensity noise (RIN) reduction. The results show that simultaneous reduction of IMD3 up to 33 dB and RIN up to 20 dB employing the proposed system.","PeriodicalId":433243,"journal":{"name":"2008 International Symposium on High Capacity Optical Networks and Enabling Technologies","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122917225","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 : 2008-11-01DOI: 10.1109/HONET.2008.4810222
M. Asif, M. Haithem, M. Zafrullah
A high precision measurement setup has been realized especially for the spectral gain of erbium doped waveguide amplifier (EDWA) in a low signal regime. Each part of the set-up is shown in detail from laser light sources, objectives and tapered fibers for performing the coupling task to the light collection system and analyzing the transmitted signal from optical waveguide devices. The main individuality of this setup is that it can be aligned up to 1 nm displacement accuracy with the help of nano-positioner. Also this setup can be used for structural analysis, mode profile, and loss measurements by using different techniques of various Si-based waveguides in different geometries.
{"title":"High Precession Measurement Setup for the Spectral Gain of EDWA in a Low Signal Regime","authors":"M. Asif, M. Haithem, M. Zafrullah","doi":"10.1109/HONET.2008.4810222","DOIUrl":"https://doi.org/10.1109/HONET.2008.4810222","url":null,"abstract":"A high precision measurement setup has been realized especially for the spectral gain of erbium doped waveguide amplifier (EDWA) in a low signal regime. Each part of the set-up is shown in detail from laser light sources, objectives and tapered fibers for performing the coupling task to the light collection system and analyzing the transmitted signal from optical waveguide devices. The main individuality of this setup is that it can be aligned up to 1 nm displacement accuracy with the help of nano-positioner. Also this setup can be used for structural analysis, mode profile, and loss measurements by using different techniques of various Si-based waveguides in different geometries.","PeriodicalId":433243,"journal":{"name":"2008 International Symposium on High Capacity Optical Networks and Enabling Technologies","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127926344","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 : 2008-11-01DOI: 10.1109/HONET.2008.4810232
R. Bouhenguel, I. Mahgoub, M. Ilyas
Advances in wireless sensor networking technologies have been extended to wearable computing systems and opened a plethora of applications and opportunities in the development and integration of pervasive Bluetooth Technologies with the abundance of existing specialized technologies in monitoring, data collection, and real-time analysis and reporting. Although the Bluetooth framework is acceptably secure, there are still a number of weaknesses in the Bluetooth technology. The nature of the wireless ad hoc and the device addressing schemes still make the Bluetooth protocol vulnerable to possible attacks and risks. This paper analyzes some of the vulnerabilities of Bluetooth architecture to possible attacks and risks and the best practices and countermeasures needed to thwart these attacks that target Bluetooth devices and their attached networks. It concentrates on Bluetooth technology security issues and challenges that face wireless computing systems.
{"title":"Bluetooth Security in Wearable Computing Applications","authors":"R. Bouhenguel, I. Mahgoub, M. Ilyas","doi":"10.1109/HONET.2008.4810232","DOIUrl":"https://doi.org/10.1109/HONET.2008.4810232","url":null,"abstract":"Advances in wireless sensor networking technologies have been extended to wearable computing systems and opened a plethora of applications and opportunities in the development and integration of pervasive Bluetooth Technologies with the abundance of existing specialized technologies in monitoring, data collection, and real-time analysis and reporting. Although the Bluetooth framework is acceptably secure, there are still a number of weaknesses in the Bluetooth technology. The nature of the wireless ad hoc and the device addressing schemes still make the Bluetooth protocol vulnerable to possible attacks and risks. This paper analyzes some of the vulnerabilities of Bluetooth architecture to possible attacks and risks and the best practices and countermeasures needed to thwart these attacks that target Bluetooth devices and their attached networks. It concentrates on Bluetooth technology security issues and challenges that face wireless computing systems.","PeriodicalId":433243,"journal":{"name":"2008 International Symposium on High Capacity Optical Networks and Enabling Technologies","volume":"196 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130468255","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 : 2008-11-01DOI: 10.1109/HONET.2008.4810204
G.Y. Il, K. Dimyati
This paper is aimed to evaluate the WDM technique for an optical switch in the optical access network. The design and performance parameters consist of the inbound offered load, number of wavelengths, switch size and normalized throughput. Also, it explores the wavelength domain to demonstrate the possibility of appropriation wavelength assignment in enhancing the network throughput. The simulation results show that the proposed scheme is promising hence offers low packet queuing delay. Consequently, this paper investigates the integration of the wavelength assignment scheme on top of the optical layer. This paper appears as the resolution in minimizing the chances of packet collisions via an eccentric approach in exploiting the substantial bandwidth of WDM system. This work offers flexibility as well as scalability in the high speed optical environment.
{"title":"Performance evaluation of wavelength assignment and collision diminution for WDM switch","authors":"G.Y. Il, K. Dimyati","doi":"10.1109/HONET.2008.4810204","DOIUrl":"https://doi.org/10.1109/HONET.2008.4810204","url":null,"abstract":"This paper is aimed to evaluate the WDM technique for an optical switch in the optical access network. The design and performance parameters consist of the inbound offered load, number of wavelengths, switch size and normalized throughput. Also, it explores the wavelength domain to demonstrate the possibility of appropriation wavelength assignment in enhancing the network throughput. The simulation results show that the proposed scheme is promising hence offers low packet queuing delay. Consequently, this paper investigates the integration of the wavelength assignment scheme on top of the optical layer. This paper appears as the resolution in minimizing the chances of packet collisions via an eccentric approach in exploiting the substantial bandwidth of WDM system. This work offers flexibility as well as scalability in the high speed optical environment.","PeriodicalId":433243,"journal":{"name":"2008 International Symposium on High Capacity Optical Networks and Enabling Technologies","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116915574","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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