Pub Date : 2015-04-16DOI: 10.1109/NCC.2015.7084909
S. Agarwal, S. De
In this paper, we propose an efficient dynamic spectrum access protocol for secondary users (SU) communication over an agile single primary user (PU) channel. The proposed access scheme is optimized with respect to different SU back-off times and SU packet length. Via Markov chain models and numerical analysis, we derive the optimal SU packet length for optimal SU performance at a given PU traffic load. We evaluate the protocol performance in terms of SU goodput and PU collision ratio. An outline of the proposed protocol operation is also given, where the protocol adapts to the changing PU traffic load for optimized spectrum access performance. Our performance studies demonstrate that the proposed protocol offers significantly high channel utilization while keeping the PU collisions below a predefined acceptable threshold.
{"title":"A persistent link layer transmission strategy for efficient dynamic spectrum access","authors":"S. Agarwal, S. De","doi":"10.1109/NCC.2015.7084909","DOIUrl":"https://doi.org/10.1109/NCC.2015.7084909","url":null,"abstract":"In this paper, we propose an efficient dynamic spectrum access protocol for secondary users (SU) communication over an agile single primary user (PU) channel. The proposed access scheme is optimized with respect to different SU back-off times and SU packet length. Via Markov chain models and numerical analysis, we derive the optimal SU packet length for optimal SU performance at a given PU traffic load. We evaluate the protocol performance in terms of SU goodput and PU collision ratio. An outline of the proposed protocol operation is also given, where the protocol adapts to the changing PU traffic load for optimized spectrum access performance. Our performance studies demonstrate that the proposed protocol offers significantly high channel utilization while keeping the PU collisions below a predefined acceptable threshold.","PeriodicalId":302718,"journal":{"name":"2015 Twenty First National Conference on Communications (NCC)","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126176245","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 : 2015-04-16DOI: 10.1109/NCC.2015.7084923
V. Sreejith, K. Anupama, L. Gudino, R. Suriyadeepan
Area exploration in WSN is used for a multitude of applications from data collection to network maintenance. In this paper, we propose a new approach - Max-Gain approach to explore an area with obstacles by modifying the utility function of frontier-based approach. The proposed approach moves the mobile nodes to a distant unexplored optimal position rather than directing it to a near frontier. The main focus of this paper is the fast area exploration using mobile nodes. We extend this approach to recover partitions in a disconnected network and hence restore connectivity. The results indicate that our approach guarantees fast area exploration with minimum communication overhead. Proposed area exploration approach is not limited to wireless sensor networks, but to any area exploration applications using mobile units.
{"title":"A fast exploration technique in WSN for partition recovery using mobile nodes","authors":"V. Sreejith, K. Anupama, L. Gudino, R. Suriyadeepan","doi":"10.1109/NCC.2015.7084923","DOIUrl":"https://doi.org/10.1109/NCC.2015.7084923","url":null,"abstract":"Area exploration in WSN is used for a multitude of applications from data collection to network maintenance. In this paper, we propose a new approach - Max-Gain approach to explore an area with obstacles by modifying the utility function of frontier-based approach. The proposed approach moves the mobile nodes to a distant unexplored optimal position rather than directing it to a near frontier. The main focus of this paper is the fast area exploration using mobile nodes. We extend this approach to recover partitions in a disconnected network and hence restore connectivity. The results indicate that our approach guarantees fast area exploration with minimum communication overhead. Proposed area exploration approach is not limited to wireless sensor networks, but to any area exploration applications using mobile units.","PeriodicalId":302718,"journal":{"name":"2015 Twenty First National Conference on Communications (NCC)","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124515424","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 : 2015-04-16DOI: 10.1109/NCC.2015.7084831
B. Priya, S. Dandapat
In this work, a novel approach of linear transformation on speech subspace is used to preserve the properties of speech signal under stress condition. It is assumed that, there is another subspace called as speech subspace which exist and contains the properties of speech signal under neutral and stress conditions. Therefore, speech component of stress speech is determined by linear transformation on speech subspace. The dimension of speech subspace is taken to be comparatively higher than original length of feature vector of training database to capture the variations in properties of speech signals more appropriately under stress condition. The linear transformation matrix is estimated using the information of HMM which is used to model the training database (neutral speech). The HMM information is used in terms of supervector. All the experiments in this work are done by parametrizing neutral and stress speech as nonlinear (TEO-CB-Auto-Env) feature. Experimentally it is observed that, a linear relationship exist between stress speech subspace and speech subspace. After linear transformation on speech subspace, speech recognizer outperforms by 7.57 % (62.14 % to 69.71%) under angry stress condition.
{"title":"Linear transformation on speech subspace for analysis of speech under stress condition","authors":"B. Priya, S. Dandapat","doi":"10.1109/NCC.2015.7084831","DOIUrl":"https://doi.org/10.1109/NCC.2015.7084831","url":null,"abstract":"In this work, a novel approach of linear transformation on speech subspace is used to preserve the properties of speech signal under stress condition. It is assumed that, there is another subspace called as speech subspace which exist and contains the properties of speech signal under neutral and stress conditions. Therefore, speech component of stress speech is determined by linear transformation on speech subspace. The dimension of speech subspace is taken to be comparatively higher than original length of feature vector of training database to capture the variations in properties of speech signals more appropriately under stress condition. The linear transformation matrix is estimated using the information of HMM which is used to model the training database (neutral speech). The HMM information is used in terms of supervector. All the experiments in this work are done by parametrizing neutral and stress speech as nonlinear (TEO-CB-Auto-Env) feature. Experimentally it is observed that, a linear relationship exist between stress speech subspace and speech subspace. After linear transformation on speech subspace, speech recognizer outperforms by 7.57 % (62.14 % to 69.71%) under angry stress condition.","PeriodicalId":302718,"journal":{"name":"2015 Twenty First National Conference on Communications (NCC)","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126335396","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 : 2015-04-16DOI: 10.1109/NCC.2015.7084883
Srikanth Raj Chetupalli, T. Sreenivas
Estimation of linear prediction coefficients under the sparsity constraint of the prediction residue, is a modification of the traditional minimum mean square error linear predictor formulation, which accounts for the impulse nature of the residual signal for voiced speech signals. This is solved using the 1-norm minimization approach under sparsity constraints. In this paper, we develop a successive approximation algorithm for estimating the linear predictor coefficients and the sparse residual signal. We illustrate the usefulness of the proposed approach using synthetic, and also real speech examples. Experimental results in a multi-pulse based analysis-synthesis show that the proposed approach can provide better perceptual quality speech reconstruction than the orthogonal matching pursuit based algorithm, with computational time much lower than convex optimization based techniques.
{"title":"Successive approximation algorithm for LPC estimation using sparse residual constraint","authors":"Srikanth Raj Chetupalli, T. Sreenivas","doi":"10.1109/NCC.2015.7084883","DOIUrl":"https://doi.org/10.1109/NCC.2015.7084883","url":null,"abstract":"Estimation of linear prediction coefficients under the sparsity constraint of the prediction residue, is a modification of the traditional minimum mean square error linear predictor formulation, which accounts for the impulse nature of the residual signal for voiced speech signals. This is solved using the 1-norm minimization approach under sparsity constraints. In this paper, we develop a successive approximation algorithm for estimating the linear predictor coefficients and the sparse residual signal. We illustrate the usefulness of the proposed approach using synthetic, and also real speech examples. Experimental results in a multi-pulse based analysis-synthesis show that the proposed approach can provide better perceptual quality speech reconstruction than the orthogonal matching pursuit based algorithm, with computational time much lower than convex optimization based techniques.","PeriodicalId":302718,"journal":{"name":"2015 Twenty First National Conference on Communications (NCC)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130322297","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 : 2015-04-16DOI: 10.1109/NCC.2015.7084849
Nitya Tiwari, P. C. Pandey
Persons with sensorineural hearing loss experience difficulty in speech perception in noisy environments. They can benefit from signal processing for suppressing the background noise in their hearing aids. For such an application, a speech enhancement technique using spectral subtraction and noise spectrum estimation based on dynamic quantile tracking is presented. It does not involve voice activity detection or storage and sorting of past spectral samples. Enhancement of speech corrupted with different types of additive stationary and non-stationary noise showed improvement in speech quality to be equivalent to an SNR advantage of 3 - 6 dB. The technique is implemented and tested for satisfactory real-time operation, with sampling frequency of 10 kHz, on a 16-bit fixed-point DSP processor with on-chip FFT hardware.
{"title":"Speech enhancement using noise estimation based on dynamic quantile tracking for hearing impaired listeners","authors":"Nitya Tiwari, P. C. Pandey","doi":"10.1109/NCC.2015.7084849","DOIUrl":"https://doi.org/10.1109/NCC.2015.7084849","url":null,"abstract":"Persons with sensorineural hearing loss experience difficulty in speech perception in noisy environments. They can benefit from signal processing for suppressing the background noise in their hearing aids. For such an application, a speech enhancement technique using spectral subtraction and noise spectrum estimation based on dynamic quantile tracking is presented. It does not involve voice activity detection or storage and sorting of past spectral samples. Enhancement of speech corrupted with different types of additive stationary and non-stationary noise showed improvement in speech quality to be equivalent to an SNR advantage of 3 - 6 dB. The technique is implemented and tested for satisfactory real-time operation, with sampling frequency of 10 kHz, on a 16-bit fixed-point DSP processor with on-chip FFT hardware.","PeriodicalId":302718,"journal":{"name":"2015 Twenty First National Conference on Communications (NCC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130802072","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 : 2015-04-16DOI: 10.1109/NCC.2015.7084930
K. Appaiah
Single-mode fibers have traditionally been the choice for medium and long haul optical links over the past two decades, with wavelength division multiplexing (WDM) offering large amounts of bandwidth. However, the recent growth in demand for bandwidth has necessitated a further expansion of optical fiber capacity. This has prompted the development of new solutions, ranging from new fiber media to digital signal processing (DSP) techniques to enhance data rates. In this paper, we briefly review some of these new developments, particularly modern multimode fibers, few-mode fibers and the DSP techniques that enable data enhancements with these fibers. We also consider the issue of decoding complexity and analyze the effect of choosing only a subset of modes or detectors at the receiver to decode with a reduced complexity, while still preserving the data rate enhancements obtained through multiplexing.
{"title":"Detector and mode subset selection for DSP based multimode fiber links","authors":"K. Appaiah","doi":"10.1109/NCC.2015.7084930","DOIUrl":"https://doi.org/10.1109/NCC.2015.7084930","url":null,"abstract":"Single-mode fibers have traditionally been the choice for medium and long haul optical links over the past two decades, with wavelength division multiplexing (WDM) offering large amounts of bandwidth. However, the recent growth in demand for bandwidth has necessitated a further expansion of optical fiber capacity. This has prompted the development of new solutions, ranging from new fiber media to digital signal processing (DSP) techniques to enhance data rates. In this paper, we briefly review some of these new developments, particularly modern multimode fibers, few-mode fibers and the DSP techniques that enable data enhancements with these fibers. We also consider the issue of decoding complexity and analyze the effect of choosing only a subset of modes or detectors at the receiver to decode with a reduced complexity, while still preserving the data rate enhancements obtained through multiplexing.","PeriodicalId":302718,"journal":{"name":"2015 Twenty First National Conference on Communications (NCC)","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132717956","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 : 2015-04-16DOI: 10.1109/NCC.2015.7084910
Mahima Mehta, N. Akhtar, A. Karandikar
In this paper, we analyze the role of HandOver (HO) parameters in improving the mobility robustness in an Heterogeneous Network (HetNet). First, we illustrate the role of offsets in improving the offload of users from macro cell to small cell, while ensuring that overall HO performance is not adversely impacted. Second, we investigate the impact of Time To Trigger (TTT) on the mobility performance in HetNet. We analyze the performance using the HetNet mobility simulator that we have developed as per the guidelines specified in the Release 12 of the Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) standard.
{"title":"Impact of HandOver parameters on mobility performance in LTE HetNets","authors":"Mahima Mehta, N. Akhtar, A. Karandikar","doi":"10.1109/NCC.2015.7084910","DOIUrl":"https://doi.org/10.1109/NCC.2015.7084910","url":null,"abstract":"In this paper, we analyze the role of HandOver (HO) parameters in improving the mobility robustness in an Heterogeneous Network (HetNet). First, we illustrate the role of offsets in improving the offload of users from macro cell to small cell, while ensuring that overall HO performance is not adversely impacted. Second, we investigate the impact of Time To Trigger (TTT) on the mobility performance in HetNet. We analyze the performance using the HetNet mobility simulator that we have developed as per the guidelines specified in the Release 12 of the Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) standard.","PeriodicalId":302718,"journal":{"name":"2015 Twenty First National Conference on Communications (NCC)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134393755","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 : 2015-04-16DOI: 10.1109/NCC.2015.7084867
Bodhibrata Mukhopadhyay, Sanat Sarangi, Subrat Kar
Low-cost precise localization is crucial for wireless sensor networks. RSSI based localization is cost effective when compared to TOA, AOA, TDOA, ultrasonic and acoustic localization as it does not require any extra hardware, power or bandwidth. The radio of sensor nodes provides information about both the RSSI and LQI of a received radio signal. Localization error can be decreased by simultaneously observing both RSSI and LQI. We propose two novel techniques for localizing a target node using RSSI+LQI. They are Recursive Bayesian-RSSI-LQI (RB-RSSI-LQI) and Maximum a posteriori-RSSI-LQI (MAP-RSSI-LQI). A comparison between these techniques is done with the existing Mean-RSSI technique. We show that MAP-RSSI-LQI gives the best results in terms of localization error and computational complexity. The root mean square error of the RB-RSSI-LQI is 53.35% less than Mean-RSSI in case of stationary target node. The root mean square error of MAP-RSSI-LQI is 52.25% and 58.88% less than Mean-RSSI in case of stationary and mobile target nodes. A combination of simulation and experimental evaluation is used to develop and validate the proposed techniques.
{"title":"Performance evaluation of localization techniques in wireless sensor networks using RSSI and LQI","authors":"Bodhibrata Mukhopadhyay, Sanat Sarangi, Subrat Kar","doi":"10.1109/NCC.2015.7084867","DOIUrl":"https://doi.org/10.1109/NCC.2015.7084867","url":null,"abstract":"Low-cost precise localization is crucial for wireless sensor networks. RSSI based localization is cost effective when compared to TOA, AOA, TDOA, ultrasonic and acoustic localization as it does not require any extra hardware, power or bandwidth. The radio of sensor nodes provides information about both the RSSI and LQI of a received radio signal. Localization error can be decreased by simultaneously observing both RSSI and LQI. We propose two novel techniques for localizing a target node using RSSI+LQI. They are Recursive Bayesian-RSSI-LQI (RB-RSSI-LQI) and Maximum a posteriori-RSSI-LQI (MAP-RSSI-LQI). A comparison between these techniques is done with the existing Mean-RSSI technique. We show that MAP-RSSI-LQI gives the best results in terms of localization error and computational complexity. The root mean square error of the RB-RSSI-LQI is 53.35% less than Mean-RSSI in case of stationary target node. The root mean square error of MAP-RSSI-LQI is 52.25% and 58.88% less than Mean-RSSI in case of stationary and mobile target nodes. A combination of simulation and experimental evaluation is used to develop and validate the proposed techniques.","PeriodicalId":302718,"journal":{"name":"2015 Twenty First National Conference on Communications (NCC)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114326761","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 : 2015-04-16DOI: 10.1109/NCC.2015.7084875
S. ChanduD., S. S. Karthikeyan, Kanaparthi V. Phani Kumar
In an antenna array the mutual coupling between the array elements affects the resultant far filed radiation pattern. This paper presents an effective solution to the problem of mutual coupling in antenna arrays by placing sub wavelength resonators like complementary split ring resonator (CSRR) and open slot split ring resonator (OSSRR) in the ground plane. A two element patch antenna array operating at 2.4GHz is designed and simulated using ANSYS HFSS. The scattering parameters are observed for varying distances between the elements and the performance of the sub-wavelength resonators are compared in each case. By placing two OSSRR cells, a substantial variation is noticed in the surface currents on the ground plane along with an efficient 37dB reduction in coupling for a very small edge to edge separation of 0.048λ between the patches. The measured results are in good agreement with the simulated results.
{"title":"Reduction of mutual coupling in a two element patch antenna array using sub-wavelength resonators","authors":"S. ChanduD., S. S. Karthikeyan, Kanaparthi V. Phani Kumar","doi":"10.1109/NCC.2015.7084875","DOIUrl":"https://doi.org/10.1109/NCC.2015.7084875","url":null,"abstract":"In an antenna array the mutual coupling between the array elements affects the resultant far filed radiation pattern. This paper presents an effective solution to the problem of mutual coupling in antenna arrays by placing sub wavelength resonators like complementary split ring resonator (CSRR) and open slot split ring resonator (OSSRR) in the ground plane. A two element patch antenna array operating at 2.4GHz is designed and simulated using ANSYS HFSS. The scattering parameters are observed for varying distances between the elements and the performance of the sub-wavelength resonators are compared in each case. By placing two OSSRR cells, a substantial variation is noticed in the surface currents on the ground plane along with an efficient 37dB reduction in coupling for a very small edge to edge separation of 0.048λ between the patches. The measured results are in good agreement with the simulated results.","PeriodicalId":302718,"journal":{"name":"2015 Twenty First National Conference on Communications (NCC)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134418003","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 : 2015-04-16DOI: 10.1109/NCC.2015.7084864
Naman Bansal, S. Raman
Tone mapping is the process of compressing the dynamic range of a scene to make it compatible with displays with limited dynamic range. In this paper, we present a new approach for tone mapping of high dynamic range (HDR) images using edge-preserving filter. We pose it as a variational problem and derive an optimal solution. We compare the results with some of the existing tone mapping algorithms and show that our algorithm compresses the high dynamic range better while preserving the details and avoiding common artefacts. We use an online dynamic range independent metric for analysing the results by the proposed and existing operators and to detect the deviation from the reference HDR image.
{"title":"Regularized tone mapping using edge preserving filters","authors":"Naman Bansal, S. Raman","doi":"10.1109/NCC.2015.7084864","DOIUrl":"https://doi.org/10.1109/NCC.2015.7084864","url":null,"abstract":"Tone mapping is the process of compressing the dynamic range of a scene to make it compatible with displays with limited dynamic range. In this paper, we present a new approach for tone mapping of high dynamic range (HDR) images using edge-preserving filter. We pose it as a variational problem and derive an optimal solution. We compare the results with some of the existing tone mapping algorithms and show that our algorithm compresses the high dynamic range better while preserving the details and avoiding common artefacts. We use an online dynamic range independent metric for analysing the results by the proposed and existing operators and to detect the deviation from the reference HDR image.","PeriodicalId":302718,"journal":{"name":"2015 Twenty First National Conference on Communications (NCC)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124816457","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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