Pub Date : 2018-12-01DOI: 10.1142/S0129626418500159
Mengjie Lv, Shuming Zhou, Xueli Sun, Guanqin Lian, Jiafei Liu
With the rapid development of cloud computing, many large-scale data centers are being built to provide increasingly popular online application services, such as search, e-mails, WeChat, and microblog, etc. The reliability of a massive data center network is the likelihood that it performs its expected functions consistently well under the given conditions within a specified time interval. A typical approach to measure the reliability of the system is to count the mean time to failure (MTTF), which shows the time that the appearance of a certain number of faulty subsystem costs. The higher the MTTF, the more reliable the system is. In this paper, we explore the reliability of data center network DCell when it is decomposed into smaller ones along the last dimension under server (node) failure model and link failure model, respectively.
{"title":"Reliability Evaluation of Data Center Network DCell","authors":"Mengjie Lv, Shuming Zhou, Xueli Sun, Guanqin Lian, Jiafei Liu","doi":"10.1142/S0129626418500159","DOIUrl":"https://doi.org/10.1142/S0129626418500159","url":null,"abstract":"With the rapid development of cloud computing, many large-scale data centers are being built to provide increasingly popular online application services, such as search, e-mails, WeChat, and microblog, etc. The reliability of a massive data center network is the likelihood that it performs its expected functions consistently well under the given conditions within a specified time interval. A typical approach to measure the reliability of the system is to count the mean time to failure (MTTF), which shows the time that the appearance of a certain number of faulty subsystem costs. The higher the MTTF, the more reliable the system is. In this paper, we explore the reliability of data center network DCell when it is decomposed into smaller ones along the last dimension under server (node) failure model and link failure model, respectively.","PeriodicalId":422436,"journal":{"name":"Parallel Process. Lett.","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133571490","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 : 2018-09-01DOI: 10.1142/S012962641850010X
Joseph Tassone, Mike Biocchi
Security is a concept which people recognize as important, yet regularly ignore for reasons such as cost or design constraints. The world is quickly shifting towards the wireless with phenomena akin to the Internet of Thing (IoT) accelerating this progression. Technologies like Bluetooth Low Energy and Radio Frequency Identification are greatly entwined with this trend, and research has been made into reinforcing protection methods. However, security is a choice made by the designer and more often than not is given decreased priority. With the improved creativity and sophistication of malicious exploits this is becoming far less acceptable. Theft of data is trivial for a user with the correct skillset and will be successful without proper defences. Further research needs to be done in the field, and encouraging consistent security practices is an appropriate start.
安全性是一个人们认为很重要的概念，但由于成本或设计限制等原因经常被忽略。世界正在迅速转向无线，类似物联网(IoT)的现象加速了这一进程。低功耗蓝牙(Bluetooth Low Energy)、射频识别(Radio Frequency Identification)等技术与这一趋势密切相关，并对加强保护方法进行了研究。然而，安全性是由设计者做出的选择，通常被赋予的优先级较低。随着恶意攻击的创造性和复杂性的提高，这种情况变得越来越难以接受。对于拥有正确技能的用户来说，窃取数据是微不足道的，如果没有适当的防御措施，窃取数据就会成功。需要在该领域进行进一步的研究，鼓励一致的安全实践是一个适当的开始。
{"title":"The Importance of Applying Security Practices in Wireless Communication: Bluetooth Low Energy and RFID","authors":"Joseph Tassone, Mike Biocchi","doi":"10.1142/S012962641850010X","DOIUrl":"https://doi.org/10.1142/S012962641850010X","url":null,"abstract":"Security is a concept which people recognize as important, yet regularly ignore for reasons such as cost or design constraints. The world is quickly shifting towards the wireless with phenomena akin to the Internet of Thing (IoT) accelerating this progression. Technologies like Bluetooth Low Energy and Radio Frequency Identification are greatly entwined with this trend, and research has been made into reinforcing protection methods. However, security is a choice made by the designer and more often than not is given decreased priority. With the improved creativity and sophistication of malicious exploits this is becoming far less acceptable. Theft of data is trivial for a user with the correct skillset and will be successful without proper defences. Further research needs to be done in the field, and encouraging consistent security practices is an appropriate start.","PeriodicalId":422436,"journal":{"name":"Parallel Process. Lett.","volume":"91 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113970481","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 : 2018-09-01DOI: 10.1142/S0129626418500111
Peizhi Yan, Yi Feng
Gomoku is an ancient board game. The traditional approach to solving the Gomoku game is to apply tree search on a Gomoku game tree. Although the rules of Gomoku are straightforward, the game tree complexity is enormous. Unlike many other board games such as chess and Shogun, the Gomoku board state is more intuitive. That is to say, analyzing the visual patterns on a Gomoku game board is fundamental to play this game. In this paper, we designed a deep convolutional neural network model to help the machine learn from the training data (collected from human players). Based on this original neural network model, we made some changes and get two variant neural networks. We compared the performance of the original neural network with its variants in our experiments. Our original neural network model got 69% accuracy on the training data and 38% accuracy on the testing data. Because the decision made by the neural network is intuitive, we also designed a hard-coded convolution-based Gomoku evaluation function to assist the neural network in making decisions. This hybrid Gomoku artificial intelligence (AI) further improved the performance of a pure neural network-based Gomoku AI.
{"title":"Using Convolution and Deep Learning in Gomoku Game Artificial Intelligence","authors":"Peizhi Yan, Yi Feng","doi":"10.1142/S0129626418500111","DOIUrl":"https://doi.org/10.1142/S0129626418500111","url":null,"abstract":"Gomoku is an ancient board game. The traditional approach to solving the Gomoku game is to apply tree search on a Gomoku game tree. Although the rules of Gomoku are straightforward, the game tree complexity is enormous. Unlike many other board games such as chess and Shogun, the Gomoku board state is more intuitive. That is to say, analyzing the visual patterns on a Gomoku game board is fundamental to play this game. In this paper, we designed a deep convolutional neural network model to help the machine learn from the training data (collected from human players). Based on this original neural network model, we made some changes and get two variant neural networks. We compared the performance of the original neural network with its variants in our experiments. Our original neural network model got 69% accuracy on the training data and 38% accuracy on the testing data. Because the decision made by the neural network is intuitive, we also designed a hard-coded convolution-based Gomoku evaluation function to assist the neural network in making decisions. This hybrid Gomoku artificial intelligence (AI) further improved the performance of a pure neural network-based Gomoku AI.","PeriodicalId":422436,"journal":{"name":"Parallel Process. Lett.","volume":"362 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133301130","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 : 2018-09-01DOI: 10.1142/S0129626418500123
Sai Antantapantula, Christopher Melekian, E. Cheng
The matching preclusion number of a graph is the minimum number of edges whose deletion results in a graph that has neither perfect matchings nor almost perfect matchings. A graph is maximally matched if its matching preclusion number is equal to its minimum degree, and is super matched if the matching preclusion number can only be achieved by deleting all edges incident to a single vertex. In this paper, we determine the matching preclusion number and classify the optimal matching preclusion sets for the shuffle-cube graphs, a variant of the well-known hypercubes.
{"title":"Matching Preclusion for the Shuffle-Cubes","authors":"Sai Antantapantula, Christopher Melekian, E. Cheng","doi":"10.1142/S0129626418500123","DOIUrl":"https://doi.org/10.1142/S0129626418500123","url":null,"abstract":"The matching preclusion number of a graph is the minimum number of edges whose deletion results in a graph that has neither perfect matchings nor almost perfect matchings. A graph is maximally matched if its matching preclusion number is equal to its minimum degree, and is super matched if the matching preclusion number can only be achieved by deleting all edges incident to a single vertex. In this paper, we determine the matching preclusion number and classify the optimal matching preclusion sets for the shuffle-cube graphs, a variant of the well-known hypercubes.","PeriodicalId":422436,"journal":{"name":"Parallel Process. Lett.","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116486044","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 : 2018-09-01DOI: 10.1142/S0129626418500093
Stefan Kronawitter, S. Kuckuk, H. Köstler, C. Lengauer
Performance optimizations should focus not only on the computations of an application, but also on the internal data layout. A well-known problem is whether a struct of arrays or an array of structs results in a higher performance for a particular application. Even though the switch from the one to the other is fairly simple to implement, testing both transformations can become laborious and error-prone. Additionally, there are more complex data layout transformations, such as a color splitting for multi-color kernels in the domain of stencil codes, that are manually difficult. As a remedy, we propose new flexible layout transformation statements for our domain-specific language ExaSlang that support arbitrary affine transformations. Since our code generator applies them automatically to the generated code, these statements enable the simple adaptation of the data layout without the need for any other modifications of the application code. This constitutes a big advance in the ease of testing and evaluating different memory layout schemes in order to identify the best.
{"title":"Automatic Data Layout Transformations in the ExaStencils Code Generator","authors":"Stefan Kronawitter, S. Kuckuk, H. Köstler, C. Lengauer","doi":"10.1142/S0129626418500093","DOIUrl":"https://doi.org/10.1142/S0129626418500093","url":null,"abstract":"Performance optimizations should focus not only on the computations of an application, but also on the internal data layout. A well-known problem is whether a struct of arrays or an array of structs results in a higher performance for a particular application. Even though the switch from the one to the other is fairly simple to implement, testing both transformations can become laborious and error-prone. Additionally, there are more complex data layout transformations, such as a color splitting for multi-color kernels in the domain of stencil codes, that are manually difficult. As a remedy, we propose new flexible layout transformation statements for our domain-specific language ExaSlang that support arbitrary affine transformations. Since our code generator applies them automatically to the generated code, these statements enable the simple adaptation of the data layout without the need for any other modifications of the application code. This constitutes a big advance in the ease of testing and evaluating different memory layout schemes in order to identify the best.","PeriodicalId":422436,"journal":{"name":"Parallel Process. Lett.","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130961654","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 : 2018-08-20DOI: 10.1142/S0129626421500213
Paul Burkhardt
The fastest deterministic algorithms for connected components take logarithmic time and perform superlinear work on a Parallel Random Access Machine (PRAM). These algorithms maintain a spanning forest by merging and compressing trees, which requires pointer-chasing operations that increase memory access latency and are limited to shared-memory systems. Many of these PRAM algorithms are also very complicated to implement. Another popular method is “leader-contraction” where the challenge is to select a constant fraction of leaders that are adjacent to a constant fraction of non-leaders with high probability, but this can require adding more edges than were in the original graph. Instead we investigate label propagation because it is deterministic, easy to implement, and does not rely on pointer-chasing. Label propagation exchanges representative labels within a component using simple graph traversal, but it is inherently difficult to complete in a sublinear number of steps. We are able to overcome the problems with label propagation for graph connectivity. We introduce a surprisingly simple framework for deterministic, undirected graph connectivity using label propagation that is easily adaptable to many computational models. It achieves logarithmic convergence independently of the number of processors and without increasing the edge count. We employ a novel method of propagating directed edges in alternating direction while performing minimum reduction on vertex labels. We present new algorithms in PRAM, Stream, and MapReduce. Given a simple, undirected graph [Formula: see text] with [Formula: see text] vertices, [Formula: see text] edges, our approach takes O(m) work each step, but we can only prove logarithmic convergence on a path graph. It was conjectured by Liu and Tarjan (2019) to take [Formula: see text] steps or possibly [Formula: see text] steps. Our experiments on a range of difficult graphs also suggest logarithmic convergence. We leave the proof of convergence as an open problem.
{"title":"Graph Connectivity in Log Steps Using Label Propagation","authors":"Paul Burkhardt","doi":"10.1142/S0129626421500213","DOIUrl":"https://doi.org/10.1142/S0129626421500213","url":null,"abstract":"The fastest deterministic algorithms for connected components take logarithmic time and perform superlinear work on a Parallel Random Access Machine (PRAM). These algorithms maintain a spanning forest by merging and compressing trees, which requires pointer-chasing operations that increase memory access latency and are limited to shared-memory systems. Many of these PRAM algorithms are also very complicated to implement. Another popular method is “leader-contraction” where the challenge is to select a constant fraction of leaders that are adjacent to a constant fraction of non-leaders with high probability, but this can require adding more edges than were in the original graph. Instead we investigate label propagation because it is deterministic, easy to implement, and does not rely on pointer-chasing. Label propagation exchanges representative labels within a component using simple graph traversal, but it is inherently difficult to complete in a sublinear number of steps. We are able to overcome the problems with label propagation for graph connectivity. We introduce a surprisingly simple framework for deterministic, undirected graph connectivity using label propagation that is easily adaptable to many computational models. It achieves logarithmic convergence independently of the number of processors and without increasing the edge count. We employ a novel method of propagating directed edges in alternating direction while performing minimum reduction on vertex labels. We present new algorithms in PRAM, Stream, and MapReduce. Given a simple, undirected graph [Formula: see text] with [Formula: see text] vertices, [Formula: see text] edges, our approach takes O(m) work each step, but we can only prove logarithmic convergence on a path graph. It was conjectured by Liu and Tarjan (2019) to take [Formula: see text] steps or possibly [Formula: see text] steps. Our experiments on a range of difficult graphs also suggest logarithmic convergence. We leave the proof of convergence as an open problem.","PeriodicalId":422436,"journal":{"name":"Parallel Process. Lett.","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126821970","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 : 2018-06-01DOI: 10.1142/S0129626418500081
Lali Barrière, X. Muñoz, Janosch Fuchs, Walter Unger
In an online problem, the input is revealed one piece at a time. In every time step, the online algorithm has to produce a part of the output, based on the partial knowledge of the input. Such decisions are irrevocable, and thus online algorithms usually lead to nonoptimal solutions. The impact of the partial knowledge depends strongly on the problem. If the algorithm is allowed to read binary information about the future, the amount of bits read that allow the algorithm to solve the problem optimally is the so-called advice complexity. The quality of an online algorithm is measured by its competitive ratio, which compares its performance to that of an optimal offline algorithm. In this paper we study online bipartite matchings focusing on the particular case of bipartite matchings in regular graphs. We give tight upper and lower bounds on the competitive ratio of the online deterministic bipartite matching problem. The competitive ratio turns out to be asymptotically equal to the known randomized competitive ratio. Afterwards, we present an upper and lower bound for the advice complexity of the online deterministic bipartite matching problem.
{"title":"Online Matching in Regular Bipartite Graphs","authors":"Lali Barrière, X. Muñoz, Janosch Fuchs, Walter Unger","doi":"10.1142/S0129626418500081","DOIUrl":"https://doi.org/10.1142/S0129626418500081","url":null,"abstract":"In an online problem, the input is revealed one piece at a time. In every time step, the online algorithm has to produce a part of the output, based on the partial knowledge of the input. Such decisions are irrevocable, and thus online algorithms usually lead to nonoptimal solutions. The impact of the partial knowledge depends strongly on the problem. If the algorithm is allowed to read binary information about the future, the amount of bits read that allow the algorithm to solve the problem optimally is the so-called advice complexity. The quality of an online algorithm is measured by its competitive ratio, which compares its performance to that of an optimal offline algorithm. In this paper we study online bipartite matchings focusing on the particular case of bipartite matchings in regular graphs. We give tight upper and lower bounds on the competitive ratio of the online deterministic bipartite matching problem. The competitive ratio turns out to be asymptotically equal to the known randomized competitive ratio. Afterwards, we present an upper and lower bound for the advice complexity of the online deterministic bipartite matching problem.","PeriodicalId":422436,"journal":{"name":"Parallel Process. Lett.","volume":"04 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128982148","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 : 2018-06-01DOI: 10.1142/S012962641850007X
Chen Hao, Weihua Yang
We call an edge-coloring of a graph [Formula: see text] a rainbow coloring if the edges of [Formula: see text] are colored with distinct colors. For every even positive integer [Formula: see text], let [Formula: see text] denote the minimum number of colors required to color the edges of the [Formula: see text]-dimensional cube [Formula: see text], so that every copy of [Formula: see text] is rainbow. Faudree et al. [6] proved that [Formula: see text] for [Formula: see text] or [Formula: see text]. Mubayi et al. [8] showed that [Formula: see text]. In this note, we show that [Formula: see text]. Moreover, we obtain the number of 6-cycles of [Formula: see text].
{"title":"A Remark on Rainbow 6-Cycles in Hypercubes","authors":"Chen Hao, Weihua Yang","doi":"10.1142/S012962641850007X","DOIUrl":"https://doi.org/10.1142/S012962641850007X","url":null,"abstract":"We call an edge-coloring of a graph [Formula: see text] a rainbow coloring if the edges of [Formula: see text] are colored with distinct colors. For every even positive integer [Formula: see text], let [Formula: see text] denote the minimum number of colors required to color the edges of the [Formula: see text]-dimensional cube [Formula: see text], so that every copy of [Formula: see text] is rainbow. Faudree et al. [6] proved that [Formula: see text] for [Formula: see text] or [Formula: see text]. Mubayi et al. [8] showed that [Formula: see text]. In this note, we show that [Formula: see text]. Moreover, we obtain the number of 6-cycles of [Formula: see text].","PeriodicalId":422436,"journal":{"name":"Parallel Process. Lett.","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122683384","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 : 2018-04-01DOI: 10.1142/S0129626418500019
Tripti Jain, K. Schneider
In general, efficient non-blocking interconnection networks can be derived from sorting networks, and to this end, one may either follow the merge-based or the radix-based sorting paradigm. Both pa...
{"title":"The Half Cleaner Lemma: Constructing Efficient Interconnection Networks from Sorting Networks","authors":"Tripti Jain, K. Schneider","doi":"10.1142/S0129626418500019","DOIUrl":"https://doi.org/10.1142/S0129626418500019","url":null,"abstract":"In general, efficient non-blocking interconnection networks can be derived from sorting networks, and to this end, one may either follow the merge-based or the radix-based sorting paradigm. Both pa...","PeriodicalId":422436,"journal":{"name":"Parallel Process. Lett.","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114497475","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 : 2018-04-01DOI: 10.1142/S0129626418500032
S. Höfinger, T. Ruh, Ernst J. Haunschmid
Porting scientific key algorithms to HPC architectures requires a thorough understanding of the subtle balance between gain in performance and introduced overhead. Here we continue the development ...
{"title":"Fast Approximate Evaluation of Parallel Overhead from a Minimal Set of Measured Execution Times","authors":"S. Höfinger, T. Ruh, Ernst J. Haunschmid","doi":"10.1142/S0129626418500032","DOIUrl":"https://doi.org/10.1142/S0129626418500032","url":null,"abstract":"Porting scientific key algorithms to HPC architectures requires a thorough understanding of the subtle balance between gain in performance and introduced overhead. Here we continue the development ...","PeriodicalId":422436,"journal":{"name":"Parallel Process. Lett.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128954361","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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