Pub Date : 2015-03-12DOI: 10.1109/SPACES.2015.7058236
Sindhuaja Muppalla, Koteswara Rao Vaddempudi
In an industrial working environment employing multiprocessor communication using UART, noise is likely to affect the data and data may be received with errors. This kind of error occurrence may affect the working of the system resulting in an improper control. Several existing UART designs are incorporating error detection logic. This kind of logic, if detects errors, requires retransmission of corresponding data frames which take additional time for automatic repeat request (ARQ) and retransmission of data. Linear block codes like hamming code have forward error correction (FEC) as well as error detection capability. This paper presents a novel VLSI implementation of UART designed to include (8,4) extended hamming code called SEC-DED code that can correct upto one error and detect upto two errors. This improves the noise immunity of the system optimizing the error free reception of data. The whole design is implemented in Xilinx ISE 12.3 simulator targeted to Xilinx Spartan 6 FPGA.
在使用UART的多处理器通信的工业工作环境中，噪声可能会影响数据，并且可能会接收到错误的数据。这种错误的发生可能会影响系统的工作，导致控制不当。几种现有的UART设计都包含错误检测逻辑。这种逻辑，如果检测到错误，需要重新传输相应的数据帧，这需要额外的时间来自动重复请求(ARQ)和重新传输数据。汉明码等线性分组码具有前向纠错(FEC)和错误检测能力。本文提出了一种新的UART的VLSI实现，设计包括(8,4)扩展汉明码，称为SEC-DED码，可以纠正最多一个错误并检测最多两个错误。这提高了系统的抗噪声能力，优化了数据的无差错接收。整个设计在针对Xilinx Spartan 6 FPGA的Xilinx ISE 12.3模拟器上实现。
{"title":"A novel VHDL implementation of UART with single error correction and double error detection capability","authors":"Sindhuaja Muppalla, Koteswara Rao Vaddempudi","doi":"10.1109/SPACES.2015.7058236","DOIUrl":"https://doi.org/10.1109/SPACES.2015.7058236","url":null,"abstract":"In an industrial working environment employing multiprocessor communication using UART, noise is likely to affect the data and data may be received with errors. This kind of error occurrence may affect the working of the system resulting in an improper control. Several existing UART designs are incorporating error detection logic. This kind of logic, if detects errors, requires retransmission of corresponding data frames which take additional time for automatic repeat request (ARQ) and retransmission of data. Linear block codes like hamming code have forward error correction (FEC) as well as error detection capability. This paper presents a novel VLSI implementation of UART designed to include (8,4) extended hamming code called SEC-DED code that can correct upto one error and detect upto two errors. This improves the noise immunity of the system optimizing the error free reception of data. The whole design is implemented in Xilinx ISE 12.3 simulator targeted to Xilinx Spartan 6 FPGA.","PeriodicalId":432479,"journal":{"name":"2015 International Conference on Signal Processing and Communication Engineering Systems","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128932350","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 : 2015-03-12DOI: 10.1109/SPACES.2015.7058240
Sushila Choudhary, H. S. Mewara
In this paper, a new design of band-reject frequency selective surfaces is proposed. Compared to previous compact structure, the FSS proposed has a better firm performance with the dimension of a unit cell only 0.126λ × 0.126λ, where λ represents the wavelength of the resonant frequency. Above design is aimed at rejection of WLAN band (5.15-5.725) GHz. Moreover, the proposed design has a stable response with respect to different polarization characteristics and different incident angles of the incident plane wave. The squashed performance can be further improve by changing radius of patch. The design is aimed at the rejection of WLAN band.
{"title":"A band-reject frequency selective surface with stable response for WLAN applications","authors":"Sushila Choudhary, H. S. Mewara","doi":"10.1109/SPACES.2015.7058240","DOIUrl":"https://doi.org/10.1109/SPACES.2015.7058240","url":null,"abstract":"In this paper, a new design of band-reject frequency selective surfaces is proposed. Compared to previous compact structure, the FSS proposed has a better firm performance with the dimension of a unit cell only 0.126λ × 0.126λ, where λ represents the wavelength of the resonant frequency. Above design is aimed at rejection of WLAN band (5.15-5.725) GHz. Moreover, the proposed design has a stable response with respect to different polarization characteristics and different incident angles of the incident plane wave. The squashed performance can be further improve by changing radius of patch. The design is aimed at the rejection of WLAN band.","PeriodicalId":432479,"journal":{"name":"2015 International Conference on Signal Processing and Communication Engineering Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130809587","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 : 2015-03-12DOI: 10.1109/SPACES.2015.7058244
Dhruba Kumar, D. Ghosh, D. Mohanta
The advent of phasor measurement unit in power system is revolutionizing the conventional grid towards smart grid. Phasor measurement units are extremely expensive devices which takes into account many aspects of the power system that are not disclosed by the manufacturer while estimating phasors of currents and voltage. This paper aims to build a laboratory prototype of PMU which can estimate the phasor updating process of a commercial PMU at the benefit of improved measurement accuracy, reduced manufacturing cost and increased timely information.
{"title":"Simulation of phasor measurement unit (PMU) in MATLAB","authors":"Dhruba Kumar, D. Ghosh, D. Mohanta","doi":"10.1109/SPACES.2015.7058244","DOIUrl":"https://doi.org/10.1109/SPACES.2015.7058244","url":null,"abstract":"The advent of phasor measurement unit in power system is revolutionizing the conventional grid towards smart grid. Phasor measurement units are extremely expensive devices which takes into account many aspects of the power system that are not disclosed by the manufacturer while estimating phasors of currents and voltage. This paper aims to build a laboratory prototype of PMU which can estimate the phasor updating process of a commercial PMU at the benefit of improved measurement accuracy, reduced manufacturing cost and increased timely information.","PeriodicalId":432479,"journal":{"name":"2015 International Conference on Signal Processing and Communication Engineering Systems","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127878946","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 : 2015-03-12DOI: 10.1109/SPACES.2015.7058249
C. Preetham, M. Prasad
In this paper, we consider the case where two communicating cognitive radio users are not near to each other or have no direct line of sight(LOS). Some secondary users don't need the entire spectrum available to them because of their traffic demand being low. If we are able to use this unused spectrum to relay the data of other secondary users through these rich nodes, the performance of the system can be improved. In cognitive systems, that are based on OFDM channel, the different resources such as subcarrier pairing, relays to be selected for pairing and powers allocated to relays must be optimized in a way to minimize the induced interference to primary users and maximum throughput is achieved. We propose an algorithm that allocates jointly the different resources with less complexity. Performance of the system, by using the rich nodes as relays, over the OFDM channel after allocating the resources is discussed through the simulation.
{"title":"Relay, power and subchannel allocations for underlay non LOS OFDM-based cognitive networks under interference temperature","authors":"C. Preetham, M. Prasad","doi":"10.1109/SPACES.2015.7058249","DOIUrl":"https://doi.org/10.1109/SPACES.2015.7058249","url":null,"abstract":"In this paper, we consider the case where two communicating cognitive radio users are not near to each other or have no direct line of sight(LOS). Some secondary users don't need the entire spectrum available to them because of their traffic demand being low. If we are able to use this unused spectrum to relay the data of other secondary users through these rich nodes, the performance of the system can be improved. In cognitive systems, that are based on OFDM channel, the different resources such as subcarrier pairing, relays to be selected for pairing and powers allocated to relays must be optimized in a way to minimize the induced interference to primary users and maximum throughput is achieved. We propose an algorithm that allocates jointly the different resources with less complexity. Performance of the system, by using the rich nodes as relays, over the OFDM channel after allocating the resources is discussed through the simulation.","PeriodicalId":432479,"journal":{"name":"2015 International Conference on Signal Processing and Communication Engineering Systems","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123207972","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 : 2015-03-12DOI: 10.1109/SPACES.2015.7058218
T. Kumar
In recent years, brain's electrical activity is being extensively studied by researchers and application developers to realize more reliable Brain Computer interfacing (BCI) technology which can control and manipulate the physical objects in the real world. In this paper, we have extracted electroencephalography (EEG) signals from Broca's area with an EEG headband which consists of two inexpensive stainless steel electrodes without employing any noise treating hardware. Broca's area is a center in brain that stores language related knowledge. Sensory signals from skin act as interferences while a user is operating a BCI in real time environment. In this paper, the characterization of those unwanted sensory signals is done in a much simpler way. By passing the amplitude normalized neural signals through low pass filters with different cut off frequencies, it is found that transient response of neural networks in Broca's area is an under damped response. From the results of this analysis, corresponding neural network is modeled as a control system with second order transfer function by using natural frequency and damping ratio values.
{"title":"Modeling of neural networks based on transient response analysis of EEG signals from Broca's area","authors":"T. Kumar","doi":"10.1109/SPACES.2015.7058218","DOIUrl":"https://doi.org/10.1109/SPACES.2015.7058218","url":null,"abstract":"In recent years, brain's electrical activity is being extensively studied by researchers and application developers to realize more reliable Brain Computer interfacing (BCI) technology which can control and manipulate the physical objects in the real world. In this paper, we have extracted electroencephalography (EEG) signals from Broca's area with an EEG headband which consists of two inexpensive stainless steel electrodes without employing any noise treating hardware. Broca's area is a center in brain that stores language related knowledge. Sensory signals from skin act as interferences while a user is operating a BCI in real time environment. In this paper, the characterization of those unwanted sensory signals is done in a much simpler way. By passing the amplitude normalized neural signals through low pass filters with different cut off frequencies, it is found that transient response of neural networks in Broca's area is an under damped response. From the results of this analysis, corresponding neural network is modeled as a control system with second order transfer function by using natural frequency and damping ratio values.","PeriodicalId":432479,"journal":{"name":"2015 International Conference on Signal Processing and Communication Engineering Systems","volume":"27 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120920131","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 : 2015-03-12DOI: 10.1109/SPACES.2015.7058216
Anurag Pushpakar, N. Dube, D. Dhar, R. Ramakrishnan
Seamless mosaic generation is a challenging issue in the field of image processing. Multi date and multi time images vary in terms of radiometry as well as geometry of viewing, this makes the task at hand more intricate. These variations are taken care of with the help of radiometrie normalization and geo-correction. In this paper an approach is proposed for mosaicing geo corrected images acquired on different days. This approach uses inter scene normalization of the images and utilizes a mathematical morphological operator to find out the best possible seam line from the overlap area. Overall visual quality of the mosaiced product is analyzed to verify the algorithm.
{"title":"Improved image mosaicing technique using marker controlled watershed segmentation","authors":"Anurag Pushpakar, N. Dube, D. Dhar, R. Ramakrishnan","doi":"10.1109/SPACES.2015.7058216","DOIUrl":"https://doi.org/10.1109/SPACES.2015.7058216","url":null,"abstract":"Seamless mosaic generation is a challenging issue in the field of image processing. Multi date and multi time images vary in terms of radiometry as well as geometry of viewing, this makes the task at hand more intricate. These variations are taken care of with the help of radiometrie normalization and geo-correction. In this paper an approach is proposed for mosaicing geo corrected images acquired on different days. This approach uses inter scene normalization of the images and utilizes a mathematical morphological operator to find out the best possible seam line from the overlap area. Overall visual quality of the mosaiced product is analyzed to verify the algorithm.","PeriodicalId":432479,"journal":{"name":"2015 International Conference on Signal Processing and Communication Engineering Systems","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121147072","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 : 2015-03-12DOI: 10.1109/SPACES.2015.7058246
S. K. Mahto, A. Choubey, S. Suman
This paper presents synthesis of unequally spaced linear array antenna with minimum sidelobe suppression, desired beamwidth and null control using wind driven optimization (WDO) algorithm. The WDO technique is nature-inspired, population based iterative heuristic global optimization algorithm for multidimensional and multimodal problems. The array synthesis objective function is formulated and then optimizes elements location using WDO algorithm to achieve the goal of minimum sidelobe level (SLL) suppression, desired beamwidth and null placement in certain direction. The results of the WDO algorithm are validated by comparing with results obtained using PSO and other evolutionary algorithm as reported in literature for linear array (N=10). The synthesis results such as radiation pattern and convergence graph show that WDO algorithm performs far better than the common PSO, CLPSO and other evolutionary algorithms.
{"title":"Linear array synthesis with minimum side lobe level and null control using wind driven optimization","authors":"S. K. Mahto, A. Choubey, S. Suman","doi":"10.1109/SPACES.2015.7058246","DOIUrl":"https://doi.org/10.1109/SPACES.2015.7058246","url":null,"abstract":"This paper presents synthesis of unequally spaced linear array antenna with minimum sidelobe suppression, desired beamwidth and null control using wind driven optimization (WDO) algorithm. The WDO technique is nature-inspired, population based iterative heuristic global optimization algorithm for multidimensional and multimodal problems. The array synthesis objective function is formulated and then optimizes elements location using WDO algorithm to achieve the goal of minimum sidelobe level (SLL) suppression, desired beamwidth and null placement in certain direction. The results of the WDO algorithm are validated by comparing with results obtained using PSO and other evolutionary algorithm as reported in literature for linear array (N=10). The synthesis results such as radiation pattern and convergence graph show that WDO algorithm performs far better than the common PSO, CLPSO and other evolutionary algorithms.","PeriodicalId":432479,"journal":{"name":"2015 International Conference on Signal Processing and Communication Engineering Systems","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116577173","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 : 2015-03-12DOI: 10.1109/SPACES.2015.7058298
A. Siddiqua, K. Sridevi, Arshad Mohammed
Mobile ad hoc networks (MANETs) are a collection of mobile hosts which communicate with each other with no central network authority or fixed infrastructure. Due to its characteristics like mobility and heterogeneity ad hoc networks are more vulnerable to attacks. Black hole is an attack where all the packets forwarded to attacker node, by neighboring nodes, are dropped intentionally. In this paper, we propose a secure knowledge algorithm which aims to detect and prevent the black hole by considering the packet drop reasons in promiscuous mode. Existing AODV routing protocol is modified to detect and prevent the black hole attack The experiment results show that our proposed algorithm secure the AODV against black hole attack in MANETs.
{"title":"Preventing black hole attacks in MANETs using secure knowledge algorithm","authors":"A. Siddiqua, K. Sridevi, Arshad Mohammed","doi":"10.1109/SPACES.2015.7058298","DOIUrl":"https://doi.org/10.1109/SPACES.2015.7058298","url":null,"abstract":"Mobile ad hoc networks (MANETs) are a collection of mobile hosts which communicate with each other with no central network authority or fixed infrastructure. Due to its characteristics like mobility and heterogeneity ad hoc networks are more vulnerable to attacks. Black hole is an attack where all the packets forwarded to attacker node, by neighboring nodes, are dropped intentionally. In this paper, we propose a secure knowledge algorithm which aims to detect and prevent the black hole by considering the packet drop reasons in promiscuous mode. Existing AODV routing protocol is modified to detect and prevent the black hole attack The experiment results show that our proposed algorithm secure the AODV against black hole attack in MANETs.","PeriodicalId":432479,"journal":{"name":"2015 International Conference on Signal Processing and Communication Engineering Systems","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114274372","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 : 2015-03-12DOI: 10.1109/SPACES.2015.7058209
G. Dua, Navin Kumar, Ravibabu Mulaveesala
In recent years, non-stationary, non-invasive imaging methodologies demonstrated as reliable, quantitative, remote characterization and evaluation methods for characterization of biological samples. This present work incorporates a digitized frequency modulated thermal wave imaging (DFMTWI) followed by time domain analysis for bone diagnostics, especially bone with tissue, skin and muscle over layers. With a view to find the potential of the proposed approach a multi layered skin-fat-muscle-bone structure is considered. Results are obtained as correlation coefficient, time delay and phase contrast images. The acquired images clearly shows the ability of the technique to detect the density variations with improved test resolution and sensitivity.
{"title":"Applications of digitized frequency modulated thermal wave imaging for bone diagnostics","authors":"G. Dua, Navin Kumar, Ravibabu Mulaveesala","doi":"10.1109/SPACES.2015.7058209","DOIUrl":"https://doi.org/10.1109/SPACES.2015.7058209","url":null,"abstract":"In recent years, non-stationary, non-invasive imaging methodologies demonstrated as reliable, quantitative, remote characterization and evaluation methods for characterization of biological samples. This present work incorporates a digitized frequency modulated thermal wave imaging (DFMTWI) followed by time domain analysis for bone diagnostics, especially bone with tissue, skin and muscle over layers. With a view to find the potential of the proposed approach a multi layered skin-fat-muscle-bone structure is considered. Results are obtained as correlation coefficient, time delay and phase contrast images. The acquired images clearly shows the ability of the technique to detect the density variations with improved test resolution and sensitivity.","PeriodicalId":432479,"journal":{"name":"2015 International Conference on Signal Processing and Communication Engineering Systems","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131328554","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 : 2015-03-12DOI: 10.1109/SPACES.2015.7058252
B. Madhav, Jayasree Gogineni, Harini Appana, Jyothi Prathusha Chennam, Durga Sai Sri Thota, Priyanka Kotte
A compact CPW fed antenna is designed for the dual band operation. Here electromagnetic band gap structures of rectangle-shaped lattices are placed for the harmonic suppression. We observed that EBG structures are not only exhibiting the band stop characteristics, but also help to magnify the proposed antenna bandwidth. The rectangular lattice like EBG's have a frequency band gap and high surface impedance characteristics, which generally represent as in-phase reflection band. We succeeded in integrating the rectangular lattice EBG's in compact slot antenna with a CPW feeding line, to decrease the surface wave losses and bandwidth enhancement. The complete antenna analysis with radiation characteristics are presented in the current study.
{"title":"Analysis of compact coplanar waveguide fed slot antenna with EBG structure","authors":"B. Madhav, Jayasree Gogineni, Harini Appana, Jyothi Prathusha Chennam, Durga Sai Sri Thota, Priyanka Kotte","doi":"10.1109/SPACES.2015.7058252","DOIUrl":"https://doi.org/10.1109/SPACES.2015.7058252","url":null,"abstract":"A compact CPW fed antenna is designed for the dual band operation. Here electromagnetic band gap structures of rectangle-shaped lattices are placed for the harmonic suppression. We observed that EBG structures are not only exhibiting the band stop characteristics, but also help to magnify the proposed antenna bandwidth. The rectangular lattice like EBG's have a frequency band gap and high surface impedance characteristics, which generally represent as in-phase reflection band. We succeeded in integrating the rectangular lattice EBG's in compact slot antenna with a CPW feeding line, to decrease the surface wave losses and bandwidth enhancement. The complete antenna analysis with radiation characteristics are presented in the current study.","PeriodicalId":432479,"journal":{"name":"2015 International Conference on Signal Processing and Communication Engineering Systems","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115524123","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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