Pub Date : 2012-04-03DOI: 10.1109/NCC.2012.6176829
A. Jayan, P. C. Pandey
Increasing the intensity of the consonant segments relative to the nearby vowel segments, known as consonant-vowel ratio (CVR) modification, is reported to be effective in improving perception of stop consonants for listeners in noisy backgrounds and for hearing-impaired listeners. A technique for automated CVR modification using detection of acoustic landmarks corresponding to the stop release bursts, with high temporal accuracy, is investigated. Its effectiveness in improving perception of stop consonants in the presence of speech-spectrum shaped noise is evaluated by conducting listening tests on five normal-hearing subjects with VCV utterances involving six stop consonants and three vowels. The processing improved the recognition scores for stop consonants by nearly 7, 18, and 25% at SNR levels of 0, -6, and -12 dB, respectively.
{"title":"Automated CVR modification for improving perception of stop consonants","authors":"A. Jayan, P. C. Pandey","doi":"10.1109/NCC.2012.6176829","DOIUrl":"https://doi.org/10.1109/NCC.2012.6176829","url":null,"abstract":"Increasing the intensity of the consonant segments relative to the nearby vowel segments, known as consonant-vowel ratio (CVR) modification, is reported to be effective in improving perception of stop consonants for listeners in noisy backgrounds and for hearing-impaired listeners. A technique for automated CVR modification using detection of acoustic landmarks corresponding to the stop release bursts, with high temporal accuracy, is investigated. Its effectiveness in improving perception of stop consonants in the presence of speech-spectrum shaped noise is evaluated by conducting listening tests on five normal-hearing subjects with VCV utterances involving six stop consonants and three vowels. The processing improved the recognition scores for stop consonants by nearly 7, 18, and 25% at SNR levels of 0, -6, and -12 dB, respectively.","PeriodicalId":178278,"journal":{"name":"2012 National Conference on Communications (NCC)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125559777","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 : 2012-04-03DOI: 10.1109/NCC.2012.6176851
R. R. Vempada, B. Kumar, K. S. Rao
In this paper, spectral and prosodic features are explored for recognition of infant cry. Different types of infant cries considered in this work are wet-diaper, hunger and pain. In this work, mel-frequency cepstral coefficients (MFCC) are used to represent the spectral information, and short-time frame energies (STE) and pause duration are used for representing the prosodic information. Support Vector Machines (SVM) are used to capture the discriminative information with respect to above mentioned cries from the spectral and prosodic features. SVM models are developed seperately using spectral and prosodic features. For carrying out these studies, infant cry database collected under Telemedicine project at IIT-KGP has been used. The recognition performance of the developed SVM models using spectral and prosodic features is observed to be 61.11% and 57.41% respectively. In this work, we also examined the recognition performance by combining the spectral and prosodic information at feature and score levels. The recognition performance using feature and score level fusion is observed to be 74.07% and 80.56% respectively.
{"title":"Characterization of infant cries using spectral and prosodic features","authors":"R. R. Vempada, B. Kumar, K. S. Rao","doi":"10.1109/NCC.2012.6176851","DOIUrl":"https://doi.org/10.1109/NCC.2012.6176851","url":null,"abstract":"In this paper, spectral and prosodic features are explored for recognition of infant cry. Different types of infant cries considered in this work are wet-diaper, hunger and pain. In this work, mel-frequency cepstral coefficients (MFCC) are used to represent the spectral information, and short-time frame energies (STE) and pause duration are used for representing the prosodic information. Support Vector Machines (SVM) are used to capture the discriminative information with respect to above mentioned cries from the spectral and prosodic features. SVM models are developed seperately using spectral and prosodic features. For carrying out these studies, infant cry database collected under Telemedicine project at IIT-KGP has been used. The recognition performance of the developed SVM models using spectral and prosodic features is observed to be 61.11% and 57.41% respectively. In this work, we also examined the recognition performance by combining the spectral and prosodic information at feature and score levels. The recognition performance using feature and score level fusion is observed to be 74.07% and 80.56% respectively.","PeriodicalId":178278,"journal":{"name":"2012 National Conference on Communications (NCC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128238236","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 : 2012-04-03DOI: 10.1109/NCC.2012.6176767
S. U. Rani, R. Manivasakan
This paper discusses the condition under which the jitter buffer at the receiver is to be operated for minimum output variance in a TDMoIP framework. The above study would be useful in the design of synchronization algorithms at the receiver of a TDMoIP network. This work uses the results derived in [1] to the above problem. We model the receiver jitter buffer as a M/G/1 queueing system with EARMA correlations between the inter-arrival times and the service times. The motivation for the above correlation structure is that, if the service intervals depend on the arrival rate and there is correlation within service times, we can achieve a constant bit rate at the receiver, that is, emulate the TDM stream as it was sent at the transmitter. Also, analysis of such a correlated queue is analytically tractable. We derived the variance of the inter departure times, of the above queue. The analysis of the departure process and the waiting times of incoming packets of this correlated queue and the relevant simulations show that if the variance of the inter departure time process constituting output TDM stream is to be less than that of the inter arrival time process of the jitter buffer, which is modeled as M/G/1 queue, then the mean waiting time of the packets in the jitter buffer would necessarily be greater than that of independent (M/M/1) case.
{"title":"On the departure process of jitter buffer in TDMoIP","authors":"S. U. Rani, R. Manivasakan","doi":"10.1109/NCC.2012.6176767","DOIUrl":"https://doi.org/10.1109/NCC.2012.6176767","url":null,"abstract":"This paper discusses the condition under which the jitter buffer at the receiver is to be operated for minimum output variance in a TDMoIP framework. The above study would be useful in the design of synchronization algorithms at the receiver of a TDMoIP network. This work uses the results derived in [1] to the above problem. We model the receiver jitter buffer as a M/G/1 queueing system with EARMA correlations between the inter-arrival times and the service times. The motivation for the above correlation structure is that, if the service intervals depend on the arrival rate and there is correlation within service times, we can achieve a constant bit rate at the receiver, that is, emulate the TDM stream as it was sent at the transmitter. Also, analysis of such a correlated queue is analytically tractable. We derived the variance of the inter departure times, of the above queue. The analysis of the departure process and the waiting times of incoming packets of this correlated queue and the relevant simulations show that if the variance of the inter departure time process constituting output TDM stream is to be less than that of the inter arrival time process of the jitter buffer, which is modeled as M/G/1 queue, then the mean waiting time of the packets in the jitter buffer would necessarily be greater than that of independent (M/M/1) case.","PeriodicalId":178278,"journal":{"name":"2012 National Conference on Communications (NCC)","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124615501","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 : 2012-04-03DOI: 10.1109/NCC.2012.6176841
Sruti Gan Chaudhuri, C. Kumar, R. V. Rajakumar
This paper presents a DiffServ based adaptive QoS model for real-time interactive traffic in constrained bandwidth IP network without over provisioning the users. A WRR based QoS scheduling algorithm has been implemented to allocate the network resources to the users. A tuning parameter for VBR real-time traffic is also introduced in order to provide fair performance to the non real-time traffic as well. The QoS model is implemented at the transmitter edge of the network. Edge switches and routers are configured with the proposed algorithm. The simulation (using NS2) and experimental results (using a test bed with real time network scenario) are presented for validation of the proposed model.
{"title":"Validation of a DiffServ based QoS model implementation for real-time traffic in a test bed","authors":"Sruti Gan Chaudhuri, C. Kumar, R. V. Rajakumar","doi":"10.1109/NCC.2012.6176841","DOIUrl":"https://doi.org/10.1109/NCC.2012.6176841","url":null,"abstract":"This paper presents a DiffServ based adaptive QoS model for real-time interactive traffic in constrained bandwidth IP network without over provisioning the users. A WRR based QoS scheduling algorithm has been implemented to allocate the network resources to the users. A tuning parameter for VBR real-time traffic is also introduced in order to provide fair performance to the non real-time traffic as well. The QoS model is implemented at the transmitter edge of the network. Edge switches and routers are configured with the proposed algorithm. The simulation (using NS2) and experimental results (using a test bed with real time network scenario) are presented for validation of the proposed model.","PeriodicalId":178278,"journal":{"name":"2012 National Conference on Communications (NCC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131305370","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 : 2012-04-03DOI: 10.1109/NCC.2012.6176817
N. Sood, P. Sen
The paper describes the effect of using different reference oscillator frequencies in a PLL circuit. Driving the PLL circuit with reference oscillator at different frequencies results in varied phase noise performance. The objective is to find out the reference frequencies along with other related parameters at different conditions thus yielding minimized spurs and optimal phase noise of the PLL system. The results can provide a guideline on the oscillator frequency selection resulting in improvising the phase noise characteristics of the PLL system along with its trade-off with the minimization of reference spurs.
{"title":"Optimization of phase noise in a PLL circuit design","authors":"N. Sood, P. Sen","doi":"10.1109/NCC.2012.6176817","DOIUrl":"https://doi.org/10.1109/NCC.2012.6176817","url":null,"abstract":"The paper describes the effect of using different reference oscillator frequencies in a PLL circuit. Driving the PLL circuit with reference oscillator at different frequencies results in varied phase noise performance. The objective is to find out the reference frequencies along with other related parameters at different conditions thus yielding minimized spurs and optimal phase noise of the PLL system. The results can provide a guideline on the oscillator frequency selection resulting in improvising the phase noise characteristics of the PLL system along with its trade-off with the minimization of reference spurs.","PeriodicalId":178278,"journal":{"name":"2012 National Conference on Communications (NCC)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116397900","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 : 2012-04-03DOI: 10.1109/NCC.2012.6176786
Nidhi Sharma, M. Bhatnagar, Monika Agrawal
Space-time block codes (STBCs) have attracted considerable attention as they provide reliable communication in multi-antenna systems. STBCs work on the principle of multiple transmissions of a data stream from different transmit antennas in multiple time slots. This redundancy reduces the data rate of the STBCs. In this paper, we propose a mapping function for PAM and square QAM constellation. Based on this mapping function, we propose an STBC for four transmit antennas which achieves high coding gain. We derive an expression of coding gain of the proposed STBC. It is further shown that the proposed STBC achieves full diversity and has a low peak-to-average power ratio (PAPR). A low-complexity decoder for the proposed STBC is also derived. We show that the proposed STBC outperforms the existing STBCs for four transmit antennas in terms of coding gain, PAPR, and decoding complexity.
{"title":"A high coding gain and low decoding complexity STBC for four transmit antennas","authors":"Nidhi Sharma, M. Bhatnagar, Monika Agrawal","doi":"10.1109/NCC.2012.6176786","DOIUrl":"https://doi.org/10.1109/NCC.2012.6176786","url":null,"abstract":"Space-time block codes (STBCs) have attracted considerable attention as they provide reliable communication in multi-antenna systems. STBCs work on the principle of multiple transmissions of a data stream from different transmit antennas in multiple time slots. This redundancy reduces the data rate of the STBCs. In this paper, we propose a mapping function for PAM and square QAM constellation. Based on this mapping function, we propose an STBC for four transmit antennas which achieves high coding gain. We derive an expression of coding gain of the proposed STBC. It is further shown that the proposed STBC achieves full diversity and has a low peak-to-average power ratio (PAPR). A low-complexity decoder for the proposed STBC is also derived. We show that the proposed STBC outperforms the existing STBCs for four transmit antennas in terms of coding gain, PAPR, and decoding complexity.","PeriodicalId":178278,"journal":{"name":"2012 National Conference on Communications (NCC)","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127191080","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 : 2012-04-03DOI: 10.1109/NCC.2012.6176795
N. R. Guhagarkar, Rafi Ahamed Shaik
The key to high performance of MPEG-4 video compression lies in an efficient reduction of spatial and temporal redundancy. The main idea of inter prediction techniques is quick checking of the entire search area with efficient matching criterion viz. sum of absolute difference to eliminate the impossible or least matched candidates, followed by finer selection among the potentially best matched candidates. The macroblock with least SAD value will decide the motion vector. Due to object-based nature of MPEG-4, new SAD design with efficient computational ability, less area and less power in 0.18μm CMOS technology and operating frequency of 1.508GHz is proposed in the following paper.
{"title":"A high-performance architectural design for motion estimation in MPEG-4","authors":"N. R. Guhagarkar, Rafi Ahamed Shaik","doi":"10.1109/NCC.2012.6176795","DOIUrl":"https://doi.org/10.1109/NCC.2012.6176795","url":null,"abstract":"The key to high performance of MPEG-4 video compression lies in an efficient reduction of spatial and temporal redundancy. The main idea of inter prediction techniques is quick checking of the entire search area with efficient matching criterion viz. sum of absolute difference to eliminate the impossible or least matched candidates, followed by finer selection among the potentially best matched candidates. The macroblock with least SAD value will decide the motion vector. Due to object-based nature of MPEG-4, new SAD design with efficient computational ability, less area and less power in 0.18μm CMOS technology and operating frequency of 1.508GHz is proposed in the following paper.","PeriodicalId":178278,"journal":{"name":"2012 National Conference on Communications (NCC)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125985513","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 : 2012-04-03DOI: 10.1109/NCC.2012.6176913
S. K. Chaudhari, S. Nottath, M. Subramanian, H. Murthy
During peak hours, the focus of an Internet service provider (ISP) is on meeting user demand and maintaining the quality of service of a network. However this leads to under-utilization of network devices/components in different parts of the network. Since the power consumption of network devices are constant and independent of their actual workloads, the under-utilized network devices/components continue to consume the same power as that of a component working at full workload. We propose an energy aware network management system (NMS) framework based on the centralized decision management system (CDMS) reported in [1]. The system uses Bayesian belief network (BBN) to predict the utilization in different ports of network routers. The information already available in the NMS is sufficient for the proposed framework. For implementing the proposed scheme, an extended interface management information base (MIB) is proposed, which includes an operational state. Simulations are performed on two standard networks - IndiaNet and ARPANet, and the results show that with the proposed approach the CDMS is able to save approximately 10-16% of power at the cost of 1-5% end-to-end delay overhead. The cost of re-routing and Simple Network Management Protocol (SNMP) messages is minimal and acceptable considering the total power saved by CDMS.
{"title":"GREEN-IT: An approach to energy savings using energy aware network management system","authors":"S. K. Chaudhari, S. Nottath, M. Subramanian, H. Murthy","doi":"10.1109/NCC.2012.6176913","DOIUrl":"https://doi.org/10.1109/NCC.2012.6176913","url":null,"abstract":"During peak hours, the focus of an Internet service provider (ISP) is on meeting user demand and maintaining the quality of service of a network. However this leads to under-utilization of network devices/components in different parts of the network. Since the power consumption of network devices are constant and independent of their actual workloads, the under-utilized network devices/components continue to consume the same power as that of a component working at full workload. We propose an energy aware network management system (NMS) framework based on the centralized decision management system (CDMS) reported in [1]. The system uses Bayesian belief network (BBN) to predict the utilization in different ports of network routers. The information already available in the NMS is sufficient for the proposed framework. For implementing the proposed scheme, an extended interface management information base (MIB) is proposed, which includes an operational state. Simulations are performed on two standard networks - IndiaNet and ARPANet, and the results show that with the proposed approach the CDMS is able to save approximately 10-16% of power at the cost of 1-5% end-to-end delay overhead. The cost of re-routing and Simple Network Management Protocol (SNMP) messages is minimal and acceptable considering the total power saved by CDMS.","PeriodicalId":178278,"journal":{"name":"2012 National Conference on Communications (NCC)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127871343","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 : 2012-04-03DOI: 10.1109/NCC.2012.6176810
R. Raha
High frequency (HF), (3-30)MHz, and Very high frequency (VHF), (30-300)MHz, radio are the backbones of communication systems from many years. They are playing a major role in country wide communication system. Unfortunately there is no direct interface between these two radio frequencies. A lot of research work had been done to create a cross patch between HF radio and VHF radio. The search for a complete solution for this cross patch circuit is still in progress. The idea in this paper is to design at least two versions of crosspatch circuits with different mechanisms and have a comparative study between these circuits to find out which one is better. The Crosspatch circuits would be a two way communicating circuit to interface between HF and VHF frequency ranges, and will not depend on any external signal rather will take the help of an internal signal to provide the interfacing.
{"title":"Designing a patch system to interface between HF and VHF radios","authors":"R. Raha","doi":"10.1109/NCC.2012.6176810","DOIUrl":"https://doi.org/10.1109/NCC.2012.6176810","url":null,"abstract":"High frequency (HF), (3-30)MHz, and Very high frequency (VHF), (30-300)MHz, radio are the backbones of communication systems from many years. They are playing a major role in country wide communication system. Unfortunately there is no direct interface between these two radio frequencies. A lot of research work had been done to create a cross patch between HF radio and VHF radio. The search for a complete solution for this cross patch circuit is still in progress. The idea in this paper is to design at least two versions of crosspatch circuits with different mechanisms and have a comparative study between these circuits to find out which one is better. The Crosspatch circuits would be a two way communicating circuit to interface between HF and VHF frequency ranges, and will not depend on any external signal rather will take the help of an internal signal to provide the interfacing.","PeriodicalId":178278,"journal":{"name":"2012 National Conference on Communications (NCC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128756476","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 : 2012-04-03DOI: 10.1109/NCC.2012.6176844
S. Parakh, A. Jagannatham
In this paper, we propose a novel application of the Vickrey-Clarke-Groves (VCG) auction based time-frequency resource allocation for H.264 SVC based scalable video transmission in 4G wireless systems. The net transmitted video quality corresponding to the given bitrate constrained wireless system can be maximized by optimally allocating the OFDMA time-frequency resources amongst the video streams requested by the different unicast/ multicast groups. However, such a centralized allocation is susceptible to subversion resulting from misrepresentation of the characteristic video parameters by malicious users. This, in addition to resulting in a degradation of the net video quality, might also benefit the users reporting incorrect parameter values through disproportionate resource allocation. Our simulation results demonstrate that application of the proposed VCG procedure maximizes the net utility in broadcast/ multicast video streaming when true characteristic parameters are reported, while punishing malicious users when one or more parameters are misreported.
{"title":"VCG auction based optimal allocation for scalable video communication in 4G WiMAX","authors":"S. Parakh, A. Jagannatham","doi":"10.1109/NCC.2012.6176844","DOIUrl":"https://doi.org/10.1109/NCC.2012.6176844","url":null,"abstract":"In this paper, we propose a novel application of the Vickrey-Clarke-Groves (VCG) auction based time-frequency resource allocation for H.264 SVC based scalable video transmission in 4G wireless systems. The net transmitted video quality corresponding to the given bitrate constrained wireless system can be maximized by optimally allocating the OFDMA time-frequency resources amongst the video streams requested by the different unicast/ multicast groups. However, such a centralized allocation is susceptible to subversion resulting from misrepresentation of the characteristic video parameters by malicious users. This, in addition to resulting in a degradation of the net video quality, might also benefit the users reporting incorrect parameter values through disproportionate resource allocation. Our simulation results demonstrate that application of the proposed VCG procedure maximizes the net utility in broadcast/ multicast video streaming when true characteristic parameters are reported, while punishing malicious users when one or more parameters are misreported.","PeriodicalId":178278,"journal":{"name":"2012 National Conference on Communications (NCC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132562270","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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