Pub Date : 2011-03-17DOI: 10.1109/NCC.2011.5734753
Sandeep Malik, Ravi Malhotra
Most of the existing crypto drivers cannot operate effectively over the multi-core systems, resulting in high synchronization overheads. Moreover, the crypto drivers under utilize the full capacity of the hardware device underneath, resulting in low IPsec throughput. This paper discusses a design methodology that virtualizes the access to the common crypto accelerators across the multiple cores and leverages the existing feature of Linux to design a more balanced system. The new design can utilize the hardware capabilities in a better and efficient way to improve the overall crypto performance on multi-core systems.
{"title":"Performance enhancement for IPsec processing on multi-core systems","authors":"Sandeep Malik, Ravi Malhotra","doi":"10.1109/NCC.2011.5734753","DOIUrl":"https://doi.org/10.1109/NCC.2011.5734753","url":null,"abstract":"Most of the existing crypto drivers cannot operate effectively over the multi-core systems, resulting in high synchronization overheads. Moreover, the crypto drivers under utilize the full capacity of the hardware device underneath, resulting in low IPsec throughput. This paper discusses a design methodology that virtualizes the access to the common crypto accelerators across the multiple cores and leverages the existing feature of Linux to design a more balanced system. The new design can utilize the hardware capabilities in a better and efficient way to improve the overall crypto performance on multi-core systems.","PeriodicalId":158295,"journal":{"name":"2011 National Conference on Communications (NCC)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125731657","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 : 2011-03-17DOI: 10.1109/NCC.2011.5734712
S. Robinson, R. Nakkeeran
A two Dimensional Photonic Crystal based Bandpass Filter (2D-PCBPF) is proposed for C-Band of CWDM applications. It is designed with two quasi waveguides and a circular Photonic Crystal Ring Resonator (PCRR). The simulation results are obtained using 2D Finite Difference Time Domain (FDTD) method. The Photonic Bandgap (PBG) is calculated by Plane Wave Expansion (PWE) method. The proposed PCBPF is covered the entire C-Band, which extends from 1530 nm to 1565 nm. Close to 100% output efficiency is observed for the wavelength ranging from 1536 nm to 1558 nm through this simulation with 32 nm of (Full Width Half Maximum) bandwidth. The size of the device is drastically reduced from a scale of few tens of millimeters to the order of micrometers. The overall size of the proposed PCBPF is around 13 µm × 11.5 µm.
{"title":"Two dimensional photonic crystal ring resonator based Bandpass Filter for C-Band of CWDM applications","authors":"S. Robinson, R. Nakkeeran","doi":"10.1109/NCC.2011.5734712","DOIUrl":"https://doi.org/10.1109/NCC.2011.5734712","url":null,"abstract":"A two Dimensional Photonic Crystal based Bandpass Filter (2D-PCBPF) is proposed for C-Band of CWDM applications. It is designed with two quasi waveguides and a circular Photonic Crystal Ring Resonator (PCRR). The simulation results are obtained using 2D Finite Difference Time Domain (FDTD) method. The Photonic Bandgap (PBG) is calculated by Plane Wave Expansion (PWE) method. The proposed PCBPF is covered the entire C-Band, which extends from 1530 nm to 1565 nm. Close to 100% output efficiency is observed for the wavelength ranging from 1536 nm to 1558 nm through this simulation with 32 nm of (Full Width Half Maximum) bandwidth. The size of the device is drastically reduced from a scale of few tens of millimeters to the order of micrometers. The overall size of the proposed PCBPF is around 13 µm × 11.5 µm.","PeriodicalId":158295,"journal":{"name":"2011 National Conference on Communications (NCC)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131551221","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 : 2011-03-17DOI: 10.1109/NCC.2011.5734786
M. Bhuyan, D. R. Neog, M. Kar
In this paper, a novel approach for hand pose recognition by using key geometrical features of hand is proposed. A skeletal hand model is constructed to analyze the abduction and adduction movements of the fingers and these variations are modeled by multidimensional probabilistic distributions. For recognizing hand poses, proximity measures are computed between input gestures and pre-modeled gesture patterns. The proposed algorithm is more robust to the improper hand segmentation and side movements of fingers. Experimental results show that the proposed method is very much suitable for the applications related to Human Computer Interactions (HCI).
{"title":"Hand pose recognition using geometric features","authors":"M. Bhuyan, D. R. Neog, M. Kar","doi":"10.1109/NCC.2011.5734786","DOIUrl":"https://doi.org/10.1109/NCC.2011.5734786","url":null,"abstract":"In this paper, a novel approach for hand pose recognition by using key geometrical features of hand is proposed. A skeletal hand model is constructed to analyze the abduction and adduction movements of the fingers and these variations are modeled by multidimensional probabilistic distributions. For recognizing hand poses, proximity measures are computed between input gestures and pre-modeled gesture patterns. The proposed algorithm is more robust to the improper hand segmentation and side movements of fingers. Experimental results show that the proposed method is very much suitable for the applications related to Human Computer Interactions (HCI).","PeriodicalId":158295,"journal":{"name":"2011 National Conference on Communications (NCC)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124469960","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 : 2011-03-17DOI: 10.1109/NCC.2011.5734734
S. Rajeshwari, Giridhar Krishnamurthy
In this paper, we propose methods for joint design of source relay precoders that optimize the performance of two-way amplify and forward (AF) multiple input multiple output (MIMO) relay systems. In particular, we propose three iterative methods to optimize the system performance. The design criteria we consider in this paper are, the conventional Arithmetic sum of average Mean Square Error (AMSE) criteria, and the lesser know Arithmetic sum of average Bit Error Rate (ABER) criteria. The proposed methods are applicable to any number antennas at all three nodes which is advantage compared to the existing joint source relay optimization technique that optimizes the sum rate. Using the extensive simulations we observe that the proposed methods performs better than the existing techniques. By using a judicious combination of both the ABER and AMSE criteria, joint MIMO precoders for two-way relay system are constructed, which clearly outperform existing joint design.
{"title":"New approach to joint MIMO precoding for 2-way AF relay systems","authors":"S. Rajeshwari, Giridhar Krishnamurthy","doi":"10.1109/NCC.2011.5734734","DOIUrl":"https://doi.org/10.1109/NCC.2011.5734734","url":null,"abstract":"In this paper, we propose methods for joint design of source relay precoders that optimize the performance of two-way amplify and forward (AF) multiple input multiple output (MIMO) relay systems. In particular, we propose three iterative methods to optimize the system performance. The design criteria we consider in this paper are, the conventional Arithmetic sum of average Mean Square Error (AMSE) criteria, and the lesser know Arithmetic sum of average Bit Error Rate (ABER) criteria. The proposed methods are applicable to any number antennas at all three nodes which is advantage compared to the existing joint source relay optimization technique that optimizes the sum rate. Using the extensive simulations we observe that the proposed methods performs better than the existing techniques. By using a judicious combination of both the ABER and AMSE criteria, joint MIMO precoders for two-way relay system are constructed, which clearly outperform existing joint design.","PeriodicalId":158295,"journal":{"name":"2011 National Conference on Communications (NCC)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114148042","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 : 2011-03-17DOI: 10.1109/NCC.2011.5734755
T. Chattopadhyay, Sujit Das
In this paper, we propose an optical pulse compressor which consists of a number of fiber units where a fiber unit is made of a certain length of zero dispersion slope - highly nonlinear fiber (ZDS-HNLF) having higher nonlinearity and low dispersion followed by a certain length of zero dispersion slope - nonzero dispersion shifted fiber (ZDS-NZDSF) having a lower nonlinearity and higher dispersion. The resultant nonlinearity and dispersion profile of this fiber pair has a rectangular pattern and when a number of such fiber units are cascaded the overall nonlinearity and dispersion profile look like a comb. These cascaded fiber units form a rectangular comb-like dispersion and nonlinearity profiled (RCDNP) fiber. A cascade of ten such basic units can compress a 4.05 ps optical pulse down to 1.5 ps level.
{"title":"Optical pulse compression using rectangular comb-like dispersion and nonlinearity profiled fiber","authors":"T. Chattopadhyay, Sujit Das","doi":"10.1109/NCC.2011.5734755","DOIUrl":"https://doi.org/10.1109/NCC.2011.5734755","url":null,"abstract":"In this paper, we propose an optical pulse compressor which consists of a number of fiber units where a fiber unit is made of a certain length of zero dispersion slope - highly nonlinear fiber (ZDS-HNLF) having higher nonlinearity and low dispersion followed by a certain length of zero dispersion slope - nonzero dispersion shifted fiber (ZDS-NZDSF) having a lower nonlinearity and higher dispersion. The resultant nonlinearity and dispersion profile of this fiber pair has a rectangular pattern and when a number of such fiber units are cascaded the overall nonlinearity and dispersion profile look like a comb. These cascaded fiber units form a rectangular comb-like dispersion and nonlinearity profiled (RCDNP) fiber. A cascade of ten such basic units can compress a 4.05 ps optical pulse down to 1.5 ps level.","PeriodicalId":158295,"journal":{"name":"2011 National Conference on Communications (NCC)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129668828","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 : 2011-03-17DOI: 10.1109/NCC.2011.5734703
V. P. Panakkal, R. Velmurugan
Effectiveness of tracking closely moving targets depends on the capability to resolve the ambiguity in associating measurements-to-tracks. Joint probabilistic data association (JPDA) has been shown to be very effective in tracking closely moving objects, but the approach is susceptible to track coalescence. The factor graph (FG) based association scheme developed in this paper circumvents the track coalescence by avoiding multiple hypothesis equivalence with recursive updation of likelihood values. The improvement in association using factor graph based data association scheme over JPDA has been demonstrated using a simulated scenario of closely moving targets. The steady state likelihood values obtained at the end of recursive process are shown to match the likelihoods obtained from measurements.
{"title":"Effective data association scheme for tracking closely moving targets using factor graphs","authors":"V. P. Panakkal, R. Velmurugan","doi":"10.1109/NCC.2011.5734703","DOIUrl":"https://doi.org/10.1109/NCC.2011.5734703","url":null,"abstract":"Effectiveness of tracking closely moving targets depends on the capability to resolve the ambiguity in associating measurements-to-tracks. Joint probabilistic data association (JPDA) has been shown to be very effective in tracking closely moving objects, but the approach is susceptible to track coalescence. The factor graph (FG) based association scheme developed in this paper circumvents the track coalescence by avoiding multiple hypothesis equivalence with recursive updation of likelihood values. The improvement in association using factor graph based data association scheme over JPDA has been demonstrated using a simulated scenario of closely moving targets. The steady state likelihood values obtained at the end of recursive process are shown to match the likelihoods obtained from measurements.","PeriodicalId":158295,"journal":{"name":"2011 National Conference on Communications (NCC)","volume":"40 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127987114","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 : 2011-03-17DOI: 10.1109/NCC.2011.5734749
S. Kshatriya, S. R. Yerrapareddy, K. Kuchi, Giridhar Krishnamurthy
Significant throughput gains can be achieved in a multi-user MIMO (MU-MIMO) wireless system by exploiting the combination of multi-user scheduling and multi-user diversity. Open-loop MU-MIMO (OL-MU-MIMO) is a codebook based precoding technique where precoders are fixed a priori at the base station (BS) in a known fashion and the user needs to feedback which precoding vector is to be chosen referred to as precoding vector index (PVI) or stream indicator. This scheme feedbacks the channel quality indicator (CQI) which is used by the BS for allocation of modulation and coding scheme (MCS) to the scheduled users. As the precoders used at all the base stations are known a priori, estimation of co-channel interference (CCI) is accurate and there is negligible mismatch between the CQI fed back by the user in present frame and SINR experienced by the user during next frame for low Doppler, resulting in stable CQI modeling. In this paper, an extensive study is made on OL-MU-MIMO and open loop single-user MIMO (OL-SU-MIMO), with an emphasis on how OL-MU-MIMO exploits multi-user diversity to achieve high spectral efficiencies. We also derive the SINR and CQI expressions for such MU-MIMO systems, and provide simulation results which indicate that OL-MU-MIMO outperforms OL-SU-MIMO only when there are large number of users in the system.
{"title":"Performance evaluation of open loop multi-user MIMO systems","authors":"S. Kshatriya, S. R. Yerrapareddy, K. Kuchi, Giridhar Krishnamurthy","doi":"10.1109/NCC.2011.5734749","DOIUrl":"https://doi.org/10.1109/NCC.2011.5734749","url":null,"abstract":"Significant throughput gains can be achieved in a multi-user MIMO (MU-MIMO) wireless system by exploiting the combination of multi-user scheduling and multi-user diversity. Open-loop MU-MIMO (OL-MU-MIMO) is a codebook based precoding technique where precoders are fixed a priori at the base station (BS) in a known fashion and the user needs to feedback which precoding vector is to be chosen referred to as precoding vector index (PVI) or stream indicator. This scheme feedbacks the channel quality indicator (CQI) which is used by the BS for allocation of modulation and coding scheme (MCS) to the scheduled users. As the precoders used at all the base stations are known a priori, estimation of co-channel interference (CCI) is accurate and there is negligible mismatch between the CQI fed back by the user in present frame and SINR experienced by the user during next frame for low Doppler, resulting in stable CQI modeling. In this paper, an extensive study is made on OL-MU-MIMO and open loop single-user MIMO (OL-SU-MIMO), with an emphasis on how OL-MU-MIMO exploits multi-user diversity to achieve high spectral efficiencies. We also derive the SINR and CQI expressions for such MU-MIMO systems, and provide simulation results which indicate that OL-MU-MIMO outperforms OL-SU-MIMO only when there are large number of users in the system.","PeriodicalId":158295,"journal":{"name":"2011 National Conference on Communications (NCC)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127560512","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 : 2011-03-17DOI: 10.1109/NCC.2011.5734696
S. Kashyap, K. Karthik
Traditionally message authentication codes (MACs) and the process of encryption are treated as orthogonal security mechanisms, where MACs are used to prove data authenticity while encryption is used to preserve confidentiality. In this paper we propose to integrate the two in a framework where the parameterized hash value of an encrypted image is designed to be the same as the hash value of the parent unencrypted original image. This form of privacy preserving authentication has applications in database searches containing sensitive files such as sets of patient's X-ray records. The main challenge here is to develop a parametric hashing algorithm that is invariant to encryption by allowing a small part of the statistical signature of the original image to emerge despite the encryption process. Since the hash value is computed without decrypting the original data, one can prove authenticity without actually revealing the information. Our contribution is twofold: (1) Formulation of this new problem of authenticating encrypted data and (2) Development of a simple hashing algorithm applicable to encrypted images.
{"title":"Authenticating encrypted data","authors":"S. Kashyap, K. Karthik","doi":"10.1109/NCC.2011.5734696","DOIUrl":"https://doi.org/10.1109/NCC.2011.5734696","url":null,"abstract":"Traditionally message authentication codes (MACs) and the process of encryption are treated as orthogonal security mechanisms, where MACs are used to prove data authenticity while encryption is used to preserve confidentiality. In this paper we propose to integrate the two in a framework where the parameterized hash value of an encrypted image is designed to be the same as the hash value of the parent unencrypted original image. This form of privacy preserving authentication has applications in database searches containing sensitive files such as sets of patient's X-ray records. The main challenge here is to develop a parametric hashing algorithm that is invariant to encryption by allowing a small part of the statistical signature of the original image to emerge despite the encryption process. Since the hash value is computed without decrypting the original data, one can prove authenticity without actually revealing the information. Our contribution is twofold: (1) Formulation of this new problem of authenticating encrypted data and (2) Development of a simple hashing algorithm applicable to encrypted images.","PeriodicalId":158295,"journal":{"name":"2011 National Conference on Communications (NCC)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128047308","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 : 2011-03-17DOI: 10.1109/NCC.2011.5734739
D. Packiaraj, M. Ramesh, A. T. Kalghatgi, K. Vinoy
Design of a dual band pass filter employing microstrip line with defected ground is presented in this paper. A dual band filter at 2.45GHz and 3.5GHz (covering WLAN and WiMAX) with 6% bandwidth has been designed at each frequency. Apertures in ground plane were used to improve the stop band rejection characteristics and coupling levels in the filter. Measured results of the experimental filter were compared against the simulation results for the purpose of validation.
{"title":"Dual band(WLAN & WiMAX) suppressed harmonic microstrip filter with perturbed ground","authors":"D. Packiaraj, M. Ramesh, A. T. Kalghatgi, K. Vinoy","doi":"10.1109/NCC.2011.5734739","DOIUrl":"https://doi.org/10.1109/NCC.2011.5734739","url":null,"abstract":"Design of a dual band pass filter employing microstrip line with defected ground is presented in this paper. A dual band filter at 2.45GHz and 3.5GHz (covering WLAN and WiMAX) with 6% bandwidth has been designed at each frequency. Apertures in ground plane were used to improve the stop band rejection characteristics and coupling levels in the filter. Measured results of the experimental filter were compared against the simulation results for the purpose of validation.","PeriodicalId":158295,"journal":{"name":"2011 National Conference on Communications (NCC)","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121436977","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 : 2011-03-17DOI: 10.1109/NCC.2011.5734713
S. Madikeri, H. Murthy
This paper investigates the use of Mel Filterbank Slope (MFS) feature for speaker recognition tasks. The Mel filterbank slope feature emphasises formants in comparison with that of the conventional Mel Filterbank Cepstral Coefficients (MFCC). The effectiveness of this feature is evaluated on the NIST 2003 speaker recognition database. Results show significant gain in performance on speaker identification accuracies by 8.9% and speaker verification EER by 1.6% with no additional computational costs involved. A combination of the MFS feature along with the delta MFCC feature shows further 2.7% and 1.2% improvements in the respective tasks. Late fusion on speaker verification systems are shown to give an overall improvement of 3%.
{"title":"Mel Filter Bank energy-based Slope feature and its application to speaker recognition","authors":"S. Madikeri, H. Murthy","doi":"10.1109/NCC.2011.5734713","DOIUrl":"https://doi.org/10.1109/NCC.2011.5734713","url":null,"abstract":"This paper investigates the use of Mel Filterbank Slope (MFS) feature for speaker recognition tasks. The Mel filterbank slope feature emphasises formants in comparison with that of the conventional Mel Filterbank Cepstral Coefficients (MFCC). The effectiveness of this feature is evaluated on the NIST 2003 speaker recognition database. Results show significant gain in performance on speaker identification accuracies by 8.9% and speaker verification EER by 1.6% with no additional computational costs involved. A combination of the MFS feature along with the delta MFCC feature shows further 2.7% and 1.2% improvements in the respective tasks. Late fusion on speaker verification systems are shown to give an overall improvement of 3%.","PeriodicalId":158295,"journal":{"name":"2011 National Conference on Communications (NCC)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133043927","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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