I. Rasheed, Muhammad Abdullah, Qazi Md. Hamza Mansoor, Z. Rehman
The problem of four wave mixing (FWM) has become the principle focus for communication Engineers in designing a wavelength division multiplexing (WDM) system which is generated due to the optical nonlinear effect of fiber in multichannel systems. It has been observed through simulations results of different techniques that FWM effect becomes maximum when the fiber dispersion level approaches to zero. In this paper we have investigated the hybrid modulations for suppressing the FWM effect in 2.5Gbps system on OptiSystem Software and proposed the three hybrid modulators schemes depending upon the level of FWM suppression considering the results of eye diagram at different power levels. During simulation we use the default values of the parameters of modulators employed. Three schemes, High level reduction, Low level reduction and Intermediate level reduction have been implemented using combination of different modulators in this paper and their simulation results show that the Intermediate level reduction technique (Hybrid Tripely Technique) is comparatively the better one.
{"title":"Novel Approaches for Suppression of Four Wave Mixing in WDM System Using Concocted Modulation Techniques","authors":"I. Rasheed, Muhammad Abdullah, Qazi Md. Hamza Mansoor, Z. Rehman","doi":"10.1109/FIT.2012.19","DOIUrl":"https://doi.org/10.1109/FIT.2012.19","url":null,"abstract":"The problem of four wave mixing (FWM) has become the principle focus for communication Engineers in designing a wavelength division multiplexing (WDM) system which is generated due to the optical nonlinear effect of fiber in multichannel systems. It has been observed through simulations results of different techniques that FWM effect becomes maximum when the fiber dispersion level approaches to zero. In this paper we have investigated the hybrid modulations for suppressing the FWM effect in 2.5Gbps system on OptiSystem Software and proposed the three hybrid modulators schemes depending upon the level of FWM suppression considering the results of eye diagram at different power levels. During simulation we use the default values of the parameters of modulators employed. Three schemes, High level reduction, Low level reduction and Intermediate level reduction have been implemented using combination of different modulators in this paper and their simulation results show that the Intermediate level reduction technique (Hybrid Tripely Technique) is comparatively the better one.","PeriodicalId":166149,"journal":{"name":"2012 10th International Conference on Frontiers of Information Technology","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121039102","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}
A digraph G = (V, E) is upward planar if it has a planar drawing with all edges pointing upward. A subgraph G̃ of a digraph G with an upward planar drawing is called a maximal upward planar subgraph of G if the addition of any edge in GG to G̃ causes non-upward planarity. Binucci et al. showed that finding even the maximum upward planar subgraph of an embedded digraph Gφ is NP-Complete [1]. In this paper, we compare different algorithms to find maximal upward planar subgraph of an embedded digraph. We also use a large test suite of embedded digraphs to gain a deeper understanding of upward planarity and see how the different heuristics perform in practice.
{"title":"Comparison of Maximal Upward Planar Subgraph Computation Algorithms","authors":"A. Rextin","doi":"10.1109/FIT.2012.71","DOIUrl":"https://doi.org/10.1109/FIT.2012.71","url":null,"abstract":"A digraph G = (V, E) is upward planar if it has a planar drawing with all edges pointing upward. A subgraph G̃ of a digraph G with an upward planar drawing is called a maximal upward planar subgraph of G if the addition of any edge in GG to G̃ causes non-upward planarity. Binucci et al. showed that finding even the maximum upward planar subgraph of an embedded digraph Gφ is NP-Complete [1]. In this paper, we compare different algorithms to find maximal upward planar subgraph of an embedded digraph. We also use a large test suite of embedded digraphs to gain a deeper understanding of upward planarity and see how the different heuristics perform in practice.","PeriodicalId":166149,"journal":{"name":"2012 10th International Conference on Frontiers of Information Technology","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132352260","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}
In this paper, we experimentally investigate the combined effect of human, antenna orientation in elevation direction and the ground effect on the Received Signal Strength Indicator (RSSI) parameter in the Wireless Sensor Network (WSN). In experiment, we use MICAz motes and consider different scenarios where antenna of the transmitter node is tilted in elevation direction. The motes were placed on the ground to take into account the ground effect on the RSSI. The effect of one, two and four persons on the RSSI is recorded. For one and two persons, different walking paces e.g. slow, medium and fast pace, are analysed. However, in case of four persons, random movement is carried out between the pair of motes. The experimental results show that some antenna orientation angles have drastic effect on the RSSI, even without any human activity. The fluctuation count and range of RSSI in different scenarios with same walking pace are completely different. Therefore, an efficient human activity algorithm is need that effectively takes into count the antenna elevation and other parameters to accurately detect the human activity in the WSN deployment region.
{"title":"Combined Human, Antenna Orientation in Elevation Direction and Ground Effect on RSSI in Wireless Sensor Networks","authors":"Syed Hassan Ahmed, S. Bouk, N. Javaid, I. Sasase","doi":"10.1109/FIT.2012.17","DOIUrl":"https://doi.org/10.1109/FIT.2012.17","url":null,"abstract":"In this paper, we experimentally investigate the combined effect of human, antenna orientation in elevation direction and the ground effect on the Received Signal Strength Indicator (RSSI) parameter in the Wireless Sensor Network (WSN). In experiment, we use MICAz motes and consider different scenarios where antenna of the transmitter node is tilted in elevation direction. The motes were placed on the ground to take into account the ground effect on the RSSI. The effect of one, two and four persons on the RSSI is recorded. For one and two persons, different walking paces e.g. slow, medium and fast pace, are analysed. However, in case of four persons, random movement is carried out between the pair of motes. The experimental results show that some antenna orientation angles have drastic effect on the RSSI, even without any human activity. The fluctuation count and range of RSSI in different scenarios with same walking pace are completely different. Therefore, an efficient human activity algorithm is need that effectively takes into count the antenna elevation and other parameters to accurately detect the human activity in the WSN deployment region.","PeriodicalId":166149,"journal":{"name":"2012 10th International Conference on Frontiers of Information Technology","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126545870","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}
Muhammad Muneeb Ur Rehman, Hassan Shabbir, Sohaib Abdul Rehman, Salman Khalid Sheikh, N. Zaffar
An increasing shift from conventional incandescent lamps to CFLs followed by LED lights has taken place over the last few years. LED lights promise 80% energy conservation over existing lighting infrastructure and to a whopping 95% energy savings compared to the incandescent light bulbs. This paper presents a study conducted by authors on energy efficient lighting solutions in Pakistan. The study includes measurements of power and photo characteristics of a variety of LED lights obtained from international and local vendors along with an analysis and comparison with IEC standards. The work established a test bed to measure power and photo characteristics of different type of lights for comparative analysis. The results from measurements reveal a need of proactive regulatory authority to put restrictions on power characteristics and quality of available local lights. The work also demonstrates photo characteristics difference in local and international LED lights.
{"title":"A Comparative Analysis of Electrical and Photo Characteristics of LED Lights","authors":"Muhammad Muneeb Ur Rehman, Hassan Shabbir, Sohaib Abdul Rehman, Salman Khalid Sheikh, N. Zaffar","doi":"10.1109/FIT.2012.46","DOIUrl":"https://doi.org/10.1109/FIT.2012.46","url":null,"abstract":"An increasing shift from conventional incandescent lamps to CFLs followed by LED lights has taken place over the last few years. LED lights promise 80% energy conservation over existing lighting infrastructure and to a whopping 95% energy savings compared to the incandescent light bulbs. This paper presents a study conducted by authors on energy efficient lighting solutions in Pakistan. The study includes measurements of power and photo characteristics of a variety of LED lights obtained from international and local vendors along with an analysis and comparison with IEC standards. The work established a test bed to measure power and photo characteristics of different type of lights for comparative analysis. The results from measurements reveal a need of proactive regulatory authority to put restrictions on power characteristics and quality of available local lights. The work also demonstrates photo characteristics difference in local and international LED lights.","PeriodicalId":166149,"journal":{"name":"2012 10th International Conference on Frontiers of Information Technology","volume":"403 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115952277","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}
Theodoros Varvadoukas, Eirini Giannakidou, Javier V. Gómez, N. Mavridis
For robots to be able to fluidly collaborate with and keep company to humans in indoor spaces, they need to be able to perceive and understand such environments, including furniture and rooms. Towards that goal, we present a system for indoor furniture and room recognition for robots, which has two significant novelties: it utilizes internet-derived as well as self-captured models for training, and also uses object- and room-context information mined through the internet, in order to bootstrap and enhance its performance. Thus, the system also acts as an example of how autonomous robot entities can benefit from utilizing online information and services. Many interesting sub problems, including the peculiarities of utilizing such online sources, are discussed, followed by a real world empirical evaluation of the system, which shows highly promising results.
{"title":"Indoor Furniture and Room Recognition for a Robot Using Internet-Derived Models and Object Context","authors":"Theodoros Varvadoukas, Eirini Giannakidou, Javier V. Gómez, N. Mavridis","doi":"10.1109/FIT.2012.30","DOIUrl":"https://doi.org/10.1109/FIT.2012.30","url":null,"abstract":"For robots to be able to fluidly collaborate with and keep company to humans in indoor spaces, they need to be able to perceive and understand such environments, including furniture and rooms. Towards that goal, we present a system for indoor furniture and room recognition for robots, which has two significant novelties: it utilizes internet-derived as well as self-captured models for training, and also uses object- and room-context information mined through the internet, in order to bootstrap and enhance its performance. Thus, the system also acts as an example of how autonomous robot entities can benefit from utilizing online information and services. Many interesting sub problems, including the peculiarities of utilizing such online sources, are discussed, followed by a real world empirical evaluation of the system, which shows highly promising results.","PeriodicalId":166149,"journal":{"name":"2012 10th International Conference on Frontiers of Information Technology","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126796177","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}
The modes of a laser resonator experience optical amplification in the same gain medium, e.g. a laser crystal, in which they spatially overlap to a significant extent. This leads to the phenomenon of mode competition or gain competition, which can be studied extensively using the optical feedback mechanism. This paper analyses the existence of two modes in a laser system in the near infra red (NIR) range. Emphasis has been laid on the position and wavelengths of the two modes. Histogram analysis of the full width at half maximum (FWHM) of the modes mirrors remarkable upshots that have been elucidated in some detail.
{"title":"Multimode Competition in Lasers in the Light of Optical Feedback","authors":"U. Masud, M. I. Baig","doi":"10.1109/FIT.2012.50","DOIUrl":"https://doi.org/10.1109/FIT.2012.50","url":null,"abstract":"The modes of a laser resonator experience optical amplification in the same gain medium, e.g. a laser crystal, in which they spatially overlap to a significant extent. This leads to the phenomenon of mode competition or gain competition, which can be studied extensively using the optical feedback mechanism. This paper analyses the existence of two modes in a laser system in the near infra red (NIR) range. Emphasis has been laid on the position and wavelengths of the two modes. Histogram analysis of the full width at half maximum (FWHM) of the modes mirrors remarkable upshots that have been elucidated in some detail.","PeriodicalId":166149,"journal":{"name":"2012 10th International Conference on Frontiers of Information Technology","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122697017","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}
An important asset in the skill set of any software project manager is the ability to somewhat accurately estimate the effort required to develop a software application. Acquiring this asset, however, requires a thorough understanding of the factors that may affect the accuracy of these estimates. This paper presents the results of an empirical study conducted to determine the causes of variation in the accuracy of effort estimations for different application and task types. A Pakistani software house that specializes in developing financial transaction processing applications is chosen for this empirical study. Actual and estimated values for software development effort are gathered and analyzed for four different types of applications - web-based, database, parallel processing, and telephony - each having six different types of tasks i.e. business-development, new features, usability, security, support, and performance. Over 1000 data points are considered. Analysis of the results reveals, for instance, that the effort for web-based applications is mostly underestimated while the effort for telephony applications is mostly overestimated. The underestimation in web-based applications is usually due to a failure to account for the learning curve associated with rapidly changing web technologies while the overestimation in telephony applications is usually due to a failure to account for the usage of third-party components.
{"title":"Determining the Factors Affecting the Accuracy of Effort Estimates for Different Application and Task Types","authors":"Saqib Bukhari, Ali Afzal Malik","doi":"10.1109/FIT.2012.16","DOIUrl":"https://doi.org/10.1109/FIT.2012.16","url":null,"abstract":"An important asset in the skill set of any software project manager is the ability to somewhat accurately estimate the effort required to develop a software application. Acquiring this asset, however, requires a thorough understanding of the factors that may affect the accuracy of these estimates. This paper presents the results of an empirical study conducted to determine the causes of variation in the accuracy of effort estimations for different application and task types. A Pakistani software house that specializes in developing financial transaction processing applications is chosen for this empirical study. Actual and estimated values for software development effort are gathered and analyzed for four different types of applications - web-based, database, parallel processing, and telephony - each having six different types of tasks i.e. business-development, new features, usability, security, support, and performance. Over 1000 data points are considered. Analysis of the results reveals, for instance, that the effort for web-based applications is mostly underestimated while the effort for telephony applications is mostly overestimated. The underestimation in web-based applications is usually due to a failure to account for the learning curve associated with rapidly changing web technologies while the overestimation in telephony applications is usually due to a failure to account for the usage of third-party components.","PeriodicalId":166149,"journal":{"name":"2012 10th International Conference on Frontiers of Information Technology","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123034712","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}
The aim of this paper is to explore the application of Neuro-Evolutionary Techniques to the diagnosis of various diseases. We applied the evolutionary technique of Cartesian Genetic programming Evolved Artificial Neural Network (CG-PANN) for the detection of three important diseases. Some cases showed excellent results while others are in the process of experimentation. In the first case we worked on diagnosing the extent of Parkinson's disease using a computer based test. Experiments in this case are in progress. In the second case, we applied the Fine Needle Aspirate (FNA) data for Breast Cancer from the WDBC website to our network to classify the samples as either benign (non-cancerous) or malignant (cancerous). The results from these experiments were highly satisfactory. In the third case, we developed a modified form of Pan-Tompkins's algorithm to detect the fiducial points from ECG signals and extracted key features from them. The features shall be applied to our network to classify the signals for the different types of Arrhythmias. Experimentation is still in progress.
{"title":"Bio-signal Processing Using Cartesian Genetic Programming Evolved Artificial Neural Network (CGPANN)","authors":"A. Ahmad, G. M. Khan","doi":"10.1109/FIT.2012.54","DOIUrl":"https://doi.org/10.1109/FIT.2012.54","url":null,"abstract":"The aim of this paper is to explore the application of Neuro-Evolutionary Techniques to the diagnosis of various diseases. We applied the evolutionary technique of Cartesian Genetic programming Evolved Artificial Neural Network (CG-PANN) for the detection of three important diseases. Some cases showed excellent results while others are in the process of experimentation. In the first case we worked on diagnosing the extent of Parkinson's disease using a computer based test. Experiments in this case are in progress. In the second case, we applied the Fine Needle Aspirate (FNA) data for Breast Cancer from the WDBC website to our network to classify the samples as either benign (non-cancerous) or malignant (cancerous). The results from these experiments were highly satisfactory. In the third case, we developed a modified form of Pan-Tompkins's algorithm to detect the fiducial points from ECG signals and extracted key features from them. The features shall be applied to our network to classify the signals for the different types of Arrhythmias. Experimentation is still in progress.","PeriodicalId":166149,"journal":{"name":"2012 10th International Conference on Frontiers of Information Technology","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128013338","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}
Statistical spectrum sensing is a promising method which can reliably detect the primary users while requiring little prior information in cognitive radio networks. In this paper, we present an overview of sensing methods based on Goodness-of-Fit tests. We discuss the performance of Energy Detector (ED) sensing, Anderson Darling (AD) sensing, Cram'er VonMises(CVM) sensing and Order Statistic (OS) sensing and we compare the results using Monte-Carlo simulations. It is shown that OS sensing outperforms ED sensing, CVM sensing and AD sensing. Next it is shown through simulations that the OS test statistic does not provide maximum probability of detection for a desired probability of false alarm and results are provided showing the regions of high probability of detection for desired probability of false alarm.
{"title":"Statistical Spectrum Sensing in Cognitive Radio","authors":"A. W. Azim, S. S. Khalid, S. Abrar","doi":"10.1109/FIT.2012.34","DOIUrl":"https://doi.org/10.1109/FIT.2012.34","url":null,"abstract":"Statistical spectrum sensing is a promising method which can reliably detect the primary users while requiring little prior information in cognitive radio networks. In this paper, we present an overview of sensing methods based on Goodness-of-Fit tests. We discuss the performance of Energy Detector (ED) sensing, Anderson Darling (AD) sensing, Cram'er VonMises(CVM) sensing and Order Statistic (OS) sensing and we compare the results using Monte-Carlo simulations. It is shown that OS sensing outperforms ED sensing, CVM sensing and AD sensing. Next it is shown through simulations that the OS test statistic does not provide maximum probability of detection for a desired probability of false alarm and results are provided showing the regions of high probability of detection for desired probability of false alarm.","PeriodicalId":166149,"journal":{"name":"2012 10th International Conference on Frontiers of Information Technology","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129120405","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}
This paper studies and proposes heuristic algorithms to solve the problem of replicated server placement (RSP) with Quality of Service (QoS) constraints. Although there has been much work on RSP in multicast networks, in most of them a simplified replication model is used, therefore, their proposed solutions may not be applicable to real systems. In this paper, we use a more realistic, and generalized model for replica placement, which considers the latency restriction of the receivers (QoS), bandwidth, and storage constraints of the links and nodes. We present a mathematical formulation and propose four heuristics that are benched marked using BRITE network generator, and discuss the benefits and drawbacks of the static and dynamic approaches. The proposed heuristics are experimentally compared through simulations with respect to their performance and computational complexity under different QoS constraints. The simulation results show interesting characteristics of the studied heuristics.
{"title":"Server Replication in Multicast Networks","authors":"H. S. Kia, S. Khan","doi":"10.1109/FIT.2012.67","DOIUrl":"https://doi.org/10.1109/FIT.2012.67","url":null,"abstract":"This paper studies and proposes heuristic algorithms to solve the problem of replicated server placement (RSP) with Quality of Service (QoS) constraints. Although there has been much work on RSP in multicast networks, in most of them a simplified replication model is used, therefore, their proposed solutions may not be applicable to real systems. In this paper, we use a more realistic, and generalized model for replica placement, which considers the latency restriction of the receivers (QoS), bandwidth, and storage constraints of the links and nodes. We present a mathematical formulation and propose four heuristics that are benched marked using BRITE network generator, and discuss the benefits and drawbacks of the static and dynamic approaches. The proposed heuristics are experimentally compared through simulations with respect to their performance and computational complexity under different QoS constraints. The simulation results show interesting characteristics of the studied heuristics.","PeriodicalId":166149,"journal":{"name":"2012 10th International Conference on Frontiers of Information Technology","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126748562","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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