Pub Date : 2011-04-24DOI: 10.1109/SIECPC.2011.5876984
A. Radwan, Tarek M. Mahmoud, Essam. H. Hussein
A mobile ad hoc networks (MANETs) is a dynamic mobile wireless network that can be formed without the need for any pre-existing wired or wireless infrastructure. One of the main challenges in an ad hoc network is the design of robust routing algorithms that adapt to the frequent and randomly changing network topology. This paper proposes a novel routing scheme for MANETs, which adapts the AntNet protocol with the blocking-expanding Ring Search and Local Retransmission technique (AntNet-RSLR). According to this protocol, a group of mobile agents build paths between pair of nodes, exploring the network concurrently and exchanging obtained information to update the routing tables that decreases both of the routing message overhead and the average end to end delay less than the well known AntNet, AODV and DSR routing protocols. This led to increase the throughput more than AntNet, AODV and DSR routing protocols. AntNet-RSLR has been implemented using NS-2 simulator.
{"title":"AntNet-RSLR: A proposed Ant routing protocol for MANETs","authors":"A. Radwan, Tarek M. Mahmoud, Essam. H. Hussein","doi":"10.1109/SIECPC.2011.5876984","DOIUrl":"https://doi.org/10.1109/SIECPC.2011.5876984","url":null,"abstract":"A mobile ad hoc networks (MANETs) is a dynamic mobile wireless network that can be formed without the need for any pre-existing wired or wireless infrastructure. One of the main challenges in an ad hoc network is the design of robust routing algorithms that adapt to the frequent and randomly changing network topology. This paper proposes a novel routing scheme for MANETs, which adapts the AntNet protocol with the blocking-expanding Ring Search and Local Retransmission technique (AntNet-RSLR). According to this protocol, a group of mobile agents build paths between pair of nodes, exploring the network concurrently and exchanging obtained information to update the routing tables that decreases both of the routing message overhead and the average end to end delay less than the well known AntNet, AODV and DSR routing protocols. This led to increase the throughput more than AntNet, AODV and DSR routing protocols. AntNet-RSLR has been implemented using NS-2 simulator.","PeriodicalId":125634,"journal":{"name":"2011 Saudi International Electronics, Communications and Photonics Conference (SIECPC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131827672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-24DOI: 10.1109/SIECPC.2011.5876961
G. Dahman, R. Bultitude, R. Hafez
In this paper, the information extracted from Single-Input Multiple-Output sounding measurements is used to study the effect of several aspects of the receive antenna arrays on system performance. The extracted multipath parameters are used to synthesize the MIMO channel matrices of a hypothesized communication system having a fixed microcellular base-station and a handheld terminal moving throughout the environment, and subsequently study the effect of array configuration on mean effective link gain, eigenvalue dispersion and outage capacity under real-world channel conditions. Three configurations of a dual inverted-F receive antenna array in a generic mobile handset were studied. The work in this paper revealed that on average, the effective power gain of a MIMO link has greater effect on the achievable capacity than multiplexing gain.
{"title":"Evaluation of the communications performance achievable on base station to handheld-terminal radio links with several different practical receive antenna arrays","authors":"G. Dahman, R. Bultitude, R. Hafez","doi":"10.1109/SIECPC.2011.5876961","DOIUrl":"https://doi.org/10.1109/SIECPC.2011.5876961","url":null,"abstract":"In this paper, the information extracted from Single-Input Multiple-Output sounding measurements is used to study the effect of several aspects of the receive antenna arrays on system performance. The extracted multipath parameters are used to synthesize the MIMO channel matrices of a hypothesized communication system having a fixed microcellular base-station and a handheld terminal moving throughout the environment, and subsequently study the effect of array configuration on mean effective link gain, eigenvalue dispersion and outage capacity under real-world channel conditions. Three configurations of a dual inverted-F receive antenna array in a generic mobile handset were studied. The work in this paper revealed that on average, the effective power gain of a MIMO link has greater effect on the achievable capacity than multiplexing gain.","PeriodicalId":125634,"journal":{"name":"2011 Saudi International Electronics, Communications and Photonics Conference (SIECPC)","volume":"141 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133311315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-24DOI: 10.1109/SIECPC.2011.5876995
M. El-Moursy, H. Shawkey
Asynchronous switching is proposed to achieve low power Network on Chip. Asynchronous switching reduces the power dissipation of the network if the activity factor of the data transfer between two ports αd is less than A αc + B αclk. Closed form expressions for power dissipation of CLICHE topology are provided for both synchronous and asynchronous switching. The area of the asynchronous switch is 50% greater than the area of the synchronous switch. However, the power dissipation of asynchronous switching could be decreased by up to 75.7%. Asynchronous switching becomes more efficient as technology advances and network density increases. A reduction in power dissipation reaches 82.3% for 256 IPs with the same chip size. Even with clock gating, asyn-choronous switching achieves significant power reduction of 77.7% for 75% clock activity factor.
为了实现低功耗的片上网络，提出了异步交换技术。当两个端口之间数据传输的活度因子αd小于A αc + B αclk时，异步交换可以降低网络的功耗。给出了同步切换和异步切换时CLICHE拓扑功耗的封闭表达式。异步交换机的面积比同步交换机的面积大50%。而异步开关的功耗可降低75.7%。随着技术的进步和网络密度的增加，异步交换变得更加高效。在相同芯片尺寸的情况下，256个ip的功耗可降低82.3%。即使使用时钟门控，异步开关在75%的时钟活动因子下也能实现77.7%的显著功耗降低。
{"title":"Asynchronous switching for low-power CLICHE netwok-on-chip","authors":"M. El-Moursy, H. Shawkey","doi":"10.1109/SIECPC.2011.5876995","DOIUrl":"https://doi.org/10.1109/SIECPC.2011.5876995","url":null,"abstract":"Asynchronous switching is proposed to achieve low power Network on Chip. Asynchronous switching reduces the power dissipation of the network if the activity factor of the data transfer between two ports αd is less than A αc + B αclk. Closed form expressions for power dissipation of CLICHE topology are provided for both synchronous and asynchronous switching. The area of the asynchronous switch is 50% greater than the area of the synchronous switch. However, the power dissipation of asynchronous switching could be decreased by up to 75.7%. Asynchronous switching becomes more efficient as technology advances and network density increases. A reduction in power dissipation reaches 82.3% for 256 IPs with the same chip size. Even with clock gating, asyn-choronous switching achieves significant power reduction of 77.7% for 75% clock activity factor.","PeriodicalId":125634,"journal":{"name":"2011 Saudi International Electronics, Communications and Photonics Conference (SIECPC)","volume":"57 3-4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120903343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-24DOI: 10.1109/SIECPC.2011.5876993
Zeeshan Sattar, A. Al-Sanie, Youssouf Ould-Cheikh-Mouhamedou
The Forced Symbol Method (FSM) lowers significantly the error rate, especially in the error floor region. The core of the FSM is the application of repeated decoding, with one or more least reliable symbols being forced to certain values, when an error is detected. The main drawback of the FSM method is its peak complexity which can be high. This paper presents a new approach for reducing the peak and average complexity of the FSM, called Enhanced Forced Symbol Method (EFSM). The main core of the EFSM relies on the evaluation of a set of decisions, when decoding of a frame fails, to determine positions of symbols in decoded frame that are likely to be in error. The efficiency of the EFSM is demonstrated by its ability to reduce significantly both the peak and the average complexity by a factor of 3 to 5.7 when compared to the standard FSM, while achieving essentially the same error rate performance of the standard FSM.
{"title":"Enhanced Forced Symbol Method for improving the error rate performance of turbo codes","authors":"Zeeshan Sattar, A. Al-Sanie, Youssouf Ould-Cheikh-Mouhamedou","doi":"10.1109/SIECPC.2011.5876993","DOIUrl":"https://doi.org/10.1109/SIECPC.2011.5876993","url":null,"abstract":"The Forced Symbol Method (FSM) lowers significantly the error rate, especially in the error floor region. The core of the FSM is the application of repeated decoding, with one or more least reliable symbols being forced to certain values, when an error is detected. The main drawback of the FSM method is its peak complexity which can be high. This paper presents a new approach for reducing the peak and average complexity of the FSM, called Enhanced Forced Symbol Method (EFSM). The main core of the EFSM relies on the evaluation of a set of decisions, when decoding of a frame fails, to determine positions of symbols in decoded frame that are likely to be in error. The efficiency of the EFSM is demonstrated by its ability to reduce significantly both the peak and the average complexity by a factor of 3 to 5.7 when compared to the standard FSM, while achieving essentially the same error rate performance of the standard FSM.","PeriodicalId":125634,"journal":{"name":"2011 Saudi International Electronics, Communications and Photonics Conference (SIECPC)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116225922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-24DOI: 10.1109/SIECPC.2011.5877010
Shahid Kabir
Corrosion is a process that takes place when essential properties within a given material begin to deteriorate, after exposure to elements that recur within the environment. Radar-based detection has tended to provide unpredictable accuracy in estimating areas of corrosion-induced damage in reinforced concrete structures. This study examines and compares the efficiency of two NDT approaches, the ground penetrating radar (GPR) and the digital half-cell method, for their effectiveness in detecting the location of corroded steel, estimating the different levels of corrosion, and detecting the damaged zones of embedded pre-corroded reinforcement bars in concrete samples.
{"title":"Radar-based detection and estimation of reinforcement elements and degree of corrosion","authors":"Shahid Kabir","doi":"10.1109/SIECPC.2011.5877010","DOIUrl":"https://doi.org/10.1109/SIECPC.2011.5877010","url":null,"abstract":"Corrosion is a process that takes place when essential properties within a given material begin to deteriorate, after exposure to elements that recur within the environment. Radar-based detection has tended to provide unpredictable accuracy in estimating areas of corrosion-induced damage in reinforced concrete structures. This study examines and compares the efficiency of two NDT approaches, the ground penetrating radar (GPR) and the digital half-cell method, for their effectiveness in detecting the location of corroded steel, estimating the different levels of corrosion, and detecting the damaged zones of embedded pre-corroded reinforcement bars in concrete samples.","PeriodicalId":125634,"journal":{"name":"2011 Saudi International Electronics, Communications and Photonics Conference (SIECPC)","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122494235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-24DOI: 10.1109/SIECPC.2011.5876892
Alawi A. Al-saggaf
In a crisp commitment schemes, a commitment must be opened using a unique opening key. However in such schemes, there could be many instances where the transmission medium or channel is corrupted by some kind of communication (transmission) noise. In this paper, we proposed a new scheme that enables the injection of fuzziness property to current ordinary crisp commitment scheme. In this way, the uncertainty occurring due to the noise presence is mitigated. It is a known fact that this kind of uncertainty naturally leads to the introduction of a fuzziness dimension to the commitment problem at hand. The security characteristic of our scheme relies on any cryptographic assumption unlike the fuzzy commitment scheme in the literature, which is based on hash function and should be strongly collision-free for the scheme to be secure.
{"title":"Crisp commitment scheme based on noisy channels","authors":"Alawi A. Al-saggaf","doi":"10.1109/SIECPC.2011.5876892","DOIUrl":"https://doi.org/10.1109/SIECPC.2011.5876892","url":null,"abstract":"In a crisp commitment schemes, a commitment must be opened using a unique opening key. However in such schemes, there could be many instances where the transmission medium or channel is corrupted by some kind of communication (transmission) noise. In this paper, we proposed a new scheme that enables the injection of fuzziness property to current ordinary crisp commitment scheme. In this way, the uncertainty occurring due to the noise presence is mitigated. It is a known fact that this kind of uncertainty naturally leads to the introduction of a fuzziness dimension to the commitment problem at hand. The security characteristic of our scheme relies on any cryptographic assumption unlike the fuzzy commitment scheme in the literature, which is based on hash function and should be strongly collision-free for the scheme to be secure.","PeriodicalId":125634,"journal":{"name":"2011 Saudi International Electronics, Communications and Photonics Conference (SIECPC)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128282535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-24DOI: 10.1109/SIECPC.2011.5876893
M. Abuelma'atti
In this paper a new simple, three-parameter nonlinear mathematical model is proposed to represent the nonlinear characteristics of the power amplifier/loudspeaker nonlinearity in acoustic echo cancellers. The three parameters of the model are directly related to three distinct different sections of the nonlinear characteristic. The model and its first derivatives are continuous and stretch over the full range of input amplitudes. Using this model in conjunction with a conventional linear adaptive filter, the design of computationally efficient acoustic echo cancellers would be feasible.
{"title":"A note on the mathematical modeling of power amplifier/loudspeaker nonlinearity in acoustic echo cancellers","authors":"M. Abuelma'atti","doi":"10.1109/SIECPC.2011.5876893","DOIUrl":"https://doi.org/10.1109/SIECPC.2011.5876893","url":null,"abstract":"In this paper a new simple, three-parameter nonlinear mathematical model is proposed to represent the nonlinear characteristics of the power amplifier/loudspeaker nonlinearity in acoustic echo cancellers. The three parameters of the model are directly related to three distinct different sections of the nonlinear characteristic. The model and its first derivatives are continuous and stretch over the full range of input amplitudes. Using this model in conjunction with a conventional linear adaptive filter, the design of computationally efficient acoustic echo cancellers would be feasible.","PeriodicalId":125634,"journal":{"name":"2011 Saudi International Electronics, Communications and Photonics Conference (SIECPC)","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122308356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-24DOI: 10.1109/SIECPC.2011.5876978
C. Willers, A. Al-ghamdi, D. Bezuidenhout, N. Al-Hosiny
The protection of own aircraft assets against infrared missile threats requires a deep understanding of the vulnerability of these assets with regard to specific threats and specific environments of operation. A key capability in the protection of own assets is the ability to perform infrared measurements, analyse the data and construct signature models of aircraft, countermeasures and the background. The creation of such a capability is a complex task. A framework for capability development was used to identify all required elements and to ensure an optimal and complete programme. Topics covered include Personnel, Organisation, Support, Training, Equipment, Doctrine, Facilities, Information and Technology (POSTEDFIT). This paper reports on the process that was followed and its initial outcome after a two year project was concluded.
{"title":"Establishing an infrared measurement and modelling capability","authors":"C. Willers, A. Al-ghamdi, D. Bezuidenhout, N. Al-Hosiny","doi":"10.1109/SIECPC.2011.5876978","DOIUrl":"https://doi.org/10.1109/SIECPC.2011.5876978","url":null,"abstract":"The protection of own aircraft assets against infrared missile threats requires a deep understanding of the vulnerability of these assets with regard to specific threats and specific environments of operation. A key capability in the protection of own assets is the ability to perform infrared measurements, analyse the data and construct signature models of aircraft, countermeasures and the background. The creation of such a capability is a complex task. A framework for capability development was used to identify all required elements and to ensure an optimal and complete programme. Topics covered include Personnel, Organisation, Support, Training, Equipment, Doctrine, Facilities, Information and Technology (POSTEDFIT). This paper reports on the process that was followed and its initial outcome after a two year project was concluded.","PeriodicalId":125634,"journal":{"name":"2011 Saudi International Electronics, Communications and Photonics Conference (SIECPC)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126530356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-24DOI: 10.1109/SIECPC.2011.5877005
A. Benmerkhi, M. Bouchemat, T. Bouchemat, E. Casson
In the present paper, we present the design of a filter formed by two waveguide couplers and one microcavity in a photonic crystal (PC) with a square lattice consists of long cylinders of silicon (Si) rods. Waveguide 1 and waveguide 2 are obtained by removing one row of rods. They are used to couple light in and out the microcavity. The finite difference time domain (FDTD) method (fullwave simulator) has been used to simulate optical propagation in this filter. Two rods have been located in the input and output channel waveguides. Their numbers and size have been varied in order to optimize the transmitted power and quality factor of the microcavity. We demonstrate that the calculated Q factor for the designed cavity increases with displacing rods, while the calculated modal volume remains almost constant.
{"title":"Computing of the quality factor in a two dimensional photonic crystal microcavity","authors":"A. Benmerkhi, M. Bouchemat, T. Bouchemat, E. Casson","doi":"10.1109/SIECPC.2011.5877005","DOIUrl":"https://doi.org/10.1109/SIECPC.2011.5877005","url":null,"abstract":"In the present paper, we present the design of a filter formed by two waveguide couplers and one microcavity in a photonic crystal (PC) with a square lattice consists of long cylinders of silicon (Si) rods. Waveguide 1 and waveguide 2 are obtained by removing one row of rods. They are used to couple light in and out the microcavity. The finite difference time domain (FDTD) method (fullwave simulator) has been used to simulate optical propagation in this filter. Two rods have been located in the input and output channel waveguides. Their numbers and size have been varied in order to optimize the transmitted power and quality factor of the microcavity. We demonstrate that the calculated Q factor for the designed cavity increases with displacing rods, while the calculated modal volume remains almost constant.","PeriodicalId":125634,"journal":{"name":"2011 Saudi International Electronics, Communications and Photonics Conference (SIECPC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129383514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-24DOI: 10.1109/SIECPC.2011.5876916
A. Chaikovsky, S. Denisov, J. Grudo, M. Korol, A. Lopatsin, V. Orlovich, F. Osipenko, A. Slesar, O. Dubovik, P. Goloub, Jana Karol, D. Tanré
Lidar and sun-radiometer data of the EARLINET, CIS-LiNet and AERONET/PHOTONS stations in the East European area, space observations and local in-situ measurements were used to characterize long range aerosol transport over European regions. Brief description of technique and equipment for implementation of combined lidar and sun-radiometer approach to aerosol monitoring and results of five years observations are presented.
{"title":"Combined lidar/sun-radiometer remote sensing technique for studying long range aerosol transport","authors":"A. Chaikovsky, S. Denisov, J. Grudo, M. Korol, A. Lopatsin, V. Orlovich, F. Osipenko, A. Slesar, O. Dubovik, P. Goloub, Jana Karol, D. Tanré","doi":"10.1109/SIECPC.2011.5876916","DOIUrl":"https://doi.org/10.1109/SIECPC.2011.5876916","url":null,"abstract":"Lidar and sun-radiometer data of the EARLINET, CIS-LiNet and AERONET/PHOTONS stations in the East European area, space observations and local in-situ measurements were used to characterize long range aerosol transport over European regions. Brief description of technique and equipment for implementation of combined lidar and sun-radiometer approach to aerosol monitoring and results of five years observations are presented.","PeriodicalId":125634,"journal":{"name":"2011 Saudi International Electronics, Communications and Photonics Conference (SIECPC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132778403","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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