Traffic matrices are used in many network engineering tasks, for instance optimal network design. Unfortunately, measurements of these matrices are error-prone, a problem that is exacerbated when they are extrapolated to provide the predictions used in planning. Practical network design and management should consider sensitivity to such errors, but although robust optimisation techniques exist, it seems they are rarely used, at least in part because of the difficulty in generating an ensemble of admissible traffic matrices with a controllable error level. We address this problem in our paper by presenting a fast and flexible technique of generating synthetic traffic matrices. We demonstrate the utility of the method by presenting a methodology for robust network design based on adaptation of the mean-risk analysis concept from finance.
{"title":"Network-design sensitivity analysis","authors":"Paul Tune, M. Roughan","doi":"10.1145/2591971.2591979","DOIUrl":"https://doi.org/10.1145/2591971.2591979","url":null,"abstract":"Traffic matrices are used in many network engineering tasks, for instance optimal network design. Unfortunately, measurements of these matrices are error-prone, a problem that is exacerbated when they are extrapolated to provide the predictions used in planning. Practical network design and management should consider sensitivity to such errors, but although robust optimisation techniques exist, it seems they are rarely used, at least in part because of the difficulty in generating an ensemble of admissible traffic matrices with a controllable error level. We address this problem in our paper by presenting a fast and flexible technique of generating synthetic traffic matrices. We demonstrate the utility of the method by presenting a methodology for robust network design based on adaptation of the mean-risk analysis concept from finance.","PeriodicalId":306456,"journal":{"name":"Measurement and Modeling of Computer Systems","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127462766","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 Solid-State Drives (SSDs) with tens of flash chips and highly parallel architecture, we can speed up I/O operations by well-utilizing resources during page allocation. Proposals already exist for using static page allocation which does not balance the IO load and its efficiency depends on access address patterns. To our best knowledge, there have been no research thus far to show what happens if one or more internal resources can be freely allocated regardless of the request address. This paper explores the possibility of using different degrees of dynamism in page allocation and identifies key design opportunities that they present to improve SSD's characteristics.
{"title":"Unleashing the potentials of dynamism for page allocation strategies in SSDs","authors":"Arash Tavakkol, M. Arjomand, H. Sarbazi-Azad","doi":"10.1145/2591971.2592013","DOIUrl":"https://doi.org/10.1145/2591971.2592013","url":null,"abstract":"In Solid-State Drives (SSDs) with tens of flash chips and highly parallel architecture, we can speed up I/O operations by well-utilizing resources during page allocation. Proposals already exist for using static page allocation which does not balance the IO load and its efficiency depends on access address patterns. To our best knowledge, there have been no research thus far to show what happens if one or more internal resources can be freely allocated regardless of the request address. This paper explores the possibility of using different degrees of dynamism in page allocation and identifies key design opportunities that they present to improve SSD's characteristics.","PeriodicalId":306456,"journal":{"name":"Measurement and Modeling of Computer Systems","volume":"18 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131093939","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 variety of models have been proposed and analyzed to understand how a new innovation (e.g., a technology, a product, or even a behavior) diffuses over a social network, broadly classified into either of epidemic-based or game-based ones. In this paper, we consider a game-based model, where each individual makes a selfish, rational choice in terms of its payoff in adopting the new innovation, but with some noise. We study how diffusion effect can be maximized by seeding a subset of individuals (within a given budget), i.e., convincing them to pre-adopt a new innovation. In particular, we aim at finding `good' seeds for minimizing the time to infect all others, i.e., diffusion speed maximization. To this end, we design polynomial-time approximation algorithms for three representative classes, Erdőos-Réenyi, planted partition and geometrically structured graph models, which correspond to globally well-connected, locally well-connected with large clusters and locally well-connected with small clusters, respectively, provide their performance guarantee in terms of approximation and complexity. First, for the dense Erdős-Rényi and planted partition graphs, we show that an arbitrary seeding and a simple seeding proportional to the size of clusters are almost optimal with high probability. Second, for geometrically structured sparse graphs, including planar and d-dimensional graphs, our algorithm that (a) constructs clusters, (b) seeds the border individuals among clusters, and (c) greedily seeds inside each cluster always outputs an almost optimal solution. We validate our theoretical findings with extensive simulations under a real social graph. We believe that our results provide new practical insights on how to seed over a social network depending on its connection structure, where individuals rationally adopt a new innovation. To our best knowledge, we are the first to study such diffusion speed maximization on the game-based diffusion, while the extensive research efforts have been made in epidemic-based models, often referred to as influence maximization.
{"title":"On maximizing diffusion speed in social networks: impact of random seeding and clustering","authors":"Jungseul Ok, Youngmi Jin, Jinwoo Shin, Yung Yi","doi":"10.1145/2591971.2591991","DOIUrl":"https://doi.org/10.1145/2591971.2591991","url":null,"abstract":"A variety of models have been proposed and analyzed to understand how a new innovation (e.g., a technology, a product, or even a behavior) diffuses over a social network, broadly classified into either of epidemic-based or game-based ones. In this paper, we consider a game-based model, where each individual makes a selfish, rational choice in terms of its payoff in adopting the new innovation, but with some noise. We study how diffusion effect can be maximized by seeding a subset of individuals (within a given budget), i.e., convincing them to pre-adopt a new innovation. In particular, we aim at finding `good' seeds for minimizing the time to infect all others, i.e., diffusion speed maximization. To this end, we design polynomial-time approximation algorithms for three representative classes, Erdőos-Réenyi, planted partition and geometrically structured graph models, which correspond to globally well-connected, locally well-connected with large clusters and locally well-connected with small clusters, respectively, provide their performance guarantee in terms of approximation and complexity. First, for the dense Erdős-Rényi and planted partition graphs, we show that an arbitrary seeding and a simple seeding proportional to the size of clusters are almost optimal with high probability. Second, for geometrically structured sparse graphs, including planar and d-dimensional graphs, our algorithm that (a) constructs clusters, (b) seeds the border individuals among clusters, and (c) greedily seeds inside each cluster always outputs an almost optimal solution. We validate our theoretical findings with extensive simulations under a real social graph. We believe that our results provide new practical insights on how to seed over a social network depending on its connection structure, where individuals rationally adopt a new innovation. To our best knowledge, we are the first to study such diffusion speed maximization on the game-based diffusion, while the extensive research efforts have been made in epidemic-based models, often referred to as influence maximization.","PeriodicalId":306456,"journal":{"name":"Measurement and Modeling of Computer Systems","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132040211","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}
We develop a novel trajectory-based localization scheme which (i) identifies a user's current trajectory based on the measurements collected while the user is moving, by finding the best match among the training traces (trajectory matching) and then (ii) localizes the user on the trajectory (localization). The core requirement of both the steps is an accurate and robust algorithm to match two time-series that may contain significant noise and perturbation due to differences in mobility, devices, and environments. To achieve this, we develop an enhanced Dynamic Time Warping (DTW) alignment, and apply it to RSS, channel state information, or magnetic field measurements collected from a trajectory. We use indoor and outdoor experiments to demonstrate its effectiveness.
{"title":"Unified localization framework using trajectory signatures","authors":"S. Rallapalli, Wei Dong, L. Qiu, Yin Zhang","doi":"10.1145/2591971.2592027","DOIUrl":"https://doi.org/10.1145/2591971.2592027","url":null,"abstract":"We develop a novel trajectory-based localization scheme which (i) identifies a user's current trajectory based on the measurements collected while the user is moving, by finding the best match among the training traces (trajectory matching) and then (ii) localizes the user on the trajectory (localization). The core requirement of both the steps is an accurate and robust algorithm to match two time-series that may contain significant noise and perturbation due to differences in mobility, devices, and environments. To achieve this, we develop an enhanced Dynamic Time Warping (DTW) alignment, and apply it to RSS, channel state information, or magnetic field measurements collected from a trajectory. We use indoor and outdoor experiments to demonstrate its effectiveness.","PeriodicalId":306456,"journal":{"name":"Measurement and Modeling of Computer Systems","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123097393","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}
C. Kim, J. Rhee, Hui Zhang, Nipun Arora, Guofei Jiang, X. Zhang, Dongyan Xu
Performance bugs are frequently observed in commodity software. While profilers or source code-based tools can be used at development stage where a program is diagnosed in a well-defined environment, many performance bugs survive such a stage and affect production runs. OS kernel-level tracers are commonly used in post-development diagnosis due to their independence from programs and libraries; however, they lack detailed program-specific metrics to reason about performance problems such as function latencies and program contexts. In this paper, we propose a novel performance inference system, called IntroPerf, that generates fine-grained performance information -- like that from application profiling tools -- transparently by leveraging OS tracers that are widely available in most commodity operating systems. With system stack traces as input, IntroPerf enables transparent context-sensitive performance inference, and diagnoses application performance in a multi-layered scope ranging from user functions to the kernel. Evaluated with various performance bugs in multiple open source software projects, IntroPerf automatically ranks potential internal and external root causes of performance bugs with high accuracy without any prior knowledge about or instrumentation on the subject software. Our results show IntroPerf's effectiveness as a lightweight performance introspection tool for post-development diagnosis.
{"title":"IntroPerf: transparent context-sensitive multi-layer performance inference using system stack traces","authors":"C. Kim, J. Rhee, Hui Zhang, Nipun Arora, Guofei Jiang, X. Zhang, Dongyan Xu","doi":"10.1145/2591971.2592008","DOIUrl":"https://doi.org/10.1145/2591971.2592008","url":null,"abstract":"Performance bugs are frequently observed in commodity software. While profilers or source code-based tools can be used at development stage where a program is diagnosed in a well-defined environment, many performance bugs survive such a stage and affect production runs. OS kernel-level tracers are commonly used in post-development diagnosis due to their independence from programs and libraries; however, they lack detailed program-specific metrics to reason about performance problems such as function latencies and program contexts. In this paper, we propose a novel performance inference system, called IntroPerf, that generates fine-grained performance information -- like that from application profiling tools -- transparently by leveraging OS tracers that are widely available in most commodity operating systems. With system stack traces as input, IntroPerf enables transparent context-sensitive performance inference, and diagnoses application performance in a multi-layered scope ranging from user functions to the kernel. Evaluated with various performance bugs in multiple open source software projects, IntroPerf automatically ranks potential internal and external root causes of performance bugs with high accuracy without any prior knowledge about or instrumentation on the subject software. Our results show IntroPerf's effectiveness as a lightweight performance introspection tool for post-development diagnosis.","PeriodicalId":306456,"journal":{"name":"Measurement and Modeling of Computer Systems","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126300751","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}
We investigate the DHCP churn impact on network characterization by analyzing 18 months of DHCP, DNS, Firewall Alert, and Netflow data collected from an enterprise network of 30,000 clients. We find that DHCP churn has clear impact on network metrics.
{"title":"Impact of DHCP churn on network characterization","authors":"Long H. Vu, D. Turaga, S. Parthasarathy","doi":"10.1145/2591971.2592034","DOIUrl":"https://doi.org/10.1145/2591971.2592034","url":null,"abstract":"We investigate the DHCP churn impact on network characterization by analyzing 18 months of DHCP, DNS, Firewall Alert, and Netflow data collected from an enterprise network of 30,000 clients. We find that DHCP churn has clear impact on network metrics.","PeriodicalId":306456,"journal":{"name":"Measurement and Modeling of Computer Systems","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126091306","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 advent of multi-core architectures has brought concurrent programming to the forefront of software development. In this context, Transactional Memory (TM) has gained increasing popularity as a simpler, attractive alternative to traditional lock-based synchronization. The recent integration of Hardware TM (HTM) in the last generation of Intel commodity processors turned TM into a mainstream technology, raising a number of questions on its future and that of concurrent programming. To evaluate the potential impact of Intel's HTM, we conducted the largest study on TM to date, comparing different locking techniques, hardware and software TMs, as well as different combinations of these mechanisms, from the dual perspective of performance and power consumption. As a result we perform a workload characterization, to help programmers better exploit the currently available TM facilities, and identify important research directions.
{"title":"On the energy and performance of commodity hardware transactional memory","authors":"Nuno Diegues, P. Romano, L. Rodrigues","doi":"10.1145/2591971.2592030","DOIUrl":"https://doi.org/10.1145/2591971.2592030","url":null,"abstract":"The advent of multi-core architectures has brought concurrent programming to the forefront of software development. In this context, Transactional Memory (TM) has gained increasing popularity as a simpler, attractive alternative to traditional lock-based synchronization. The recent integration of Hardware TM (HTM) in the last generation of Intel commodity processors turned TM into a mainstream technology, raising a number of questions on its future and that of concurrent programming.\u0000 To evaluate the potential impact of Intel's HTM, we conducted the largest study on TM to date, comparing different locking techniques, hardware and software TMs, as well as different combinations of these mechanisms, from the dual perspective of performance and power consumption. As a result we perform a workload characterization, to help programmers better exploit the currently available TM facilities, and identify important research directions.","PeriodicalId":306456,"journal":{"name":"Measurement and Modeling of Computer Systems","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132834850","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 addresses the problem of a single rumor source detection with multiple observations, from a statistical point of view of a spreading over a network, based on the susceptible-infectious model. For tree networks, multiple sequential observations for one single instance of rumor spreading cannot improve over the initial snapshot observation. The situation dramatically improves for multiple independent observations. We propose a unified inference framework based on the union rumor centrality, and provide explicit detection performance for degree-regular tree networks. Surprisingly, even with merely two observations, the detection probability at least doubles that of a single observation, and further approaches one, i.e., reliable detection, with increasing degree. This indicates that a richer diversity enhances detectability. For general graphs, a detection algorithm using a breadth-first search strategy is also proposed and evaluated. Besides rumor source detection, our results can be used in network forensics to combat recurring epidemic-like information spreading such as online anomaly and fraudulent email spams.
{"title":"Rumor source detection with multiple observations: fundamental limits and algorithms","authors":"Zhaoxu Wang, Wenxiang Dong, Wenyi Zhang, C. Tan","doi":"10.1145/2591971.2591993","DOIUrl":"https://doi.org/10.1145/2591971.2591993","url":null,"abstract":"This paper addresses the problem of a single rumor source detection with multiple observations, from a statistical point of view of a spreading over a network, based on the susceptible-infectious model. For tree networks, multiple sequential observations for one single instance of rumor spreading cannot improve over the initial snapshot observation. The situation dramatically improves for multiple independent observations. We propose a unified inference framework based on the union rumor centrality, and provide explicit detection performance for degree-regular tree networks. Surprisingly, even with merely two observations, the detection probability at least doubles that of a single observation, and further approaches one, i.e., reliable detection, with increasing degree. This indicates that a richer diversity enhances detectability. For general graphs, a detection algorithm using a breadth-first search strategy is also proposed and evaluated. Besides rumor source detection, our results can be used in network forensics to combat recurring epidemic-like information spreading such as online anomaly and fraudulent email spams.","PeriodicalId":306456,"journal":{"name":"Measurement and Modeling of Computer Systems","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131911231","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}
We present an approach for building performance models of multithreaded programs automatically. We use a combination of static and a dynamic analyses of a single representative run of the program to build its model. The model can predict performance of the program under a variety of configurations. This paper outlines how we construct the model and demonstrates how the resultant models accurately predict the performance %and resource utilization of complex multithreaded programs.
{"title":"Automated analysis of multithreaded programs for performance modeling","authors":"A. Tarvo, S. Reiss","doi":"10.1145/2591971.2592016","DOIUrl":"https://doi.org/10.1145/2591971.2592016","url":null,"abstract":"We present an approach for building performance models of multithreaded programs automatically. We use a combination of static and a dynamic analyses of a single representative run of the program to build its model. The model can predict performance of the program under a variety of configurations. This paper outlines how we construct the model and demonstrates how the resultant models accurately predict the performance %and resource utilization of complex multithreaded programs.","PeriodicalId":306456,"journal":{"name":"Measurement and Modeling of Computer Systems","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124994601","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}
N. Nachiappan, Praveen Yedlapalli, N. Soundararajan, M. Kandemir, A. Sivasubramaniam, C. Das
As the demand for feature-rich mobile systems such as smartphones and tablets has outpaced other computing systems and is expected to continue at a faster rate, it is projected that SoCs with tens of cores and hundreds of IPs (or accelerator) will be designed to provide unprecedented level of features and functionality in future. Design of such mobile systems with required QoS and power budgets along with other design constraints will be a daunting task for computer architects since any ad hoc, piece-meal solution is unlikely to result in an optimal design. This requires early exploration of the complete design space to understand the system-level design trade-offs. To the best of our knowledge, there is no such publicly available tool to conduct a holistic evaluation of mobile platforms consisting of cores, IPs and system software. This paper presents GemDroid, a comprehensive simulation infrastructure to address these concerns. GemDroid has been designed by integrating the Android open-source emulator for facilitating execution of mobile applications, the GEM5 core simulator for analyzing the CPU and memory centric designs, and models for several IPs to collectively study their impact on system-level performance and power. Analyzing a spectrum of applications with GemDroid, we observed that the memory subsystem is a vital cog in the mobile platform because, it needs to handle both core and IP traffic, which have very different characteristics. Consequently, we present a heterogeneous memory controller (HMC) design, where we divide the memory physically into two address regions, where the first region with one memory controller (MC) handles core-specific application data and the second region with another MC handles all IP related data. The proposed modifications to the memory controller design results in an average 25% reduction in execution time for CPU bound applications, up to 11% reduction in frame drops, and on average 17% reduction in CPU busy time for on-screen (IP bound) applications.
{"title":"GemDroid: a framework to evaluate mobile platforms","authors":"N. Nachiappan, Praveen Yedlapalli, N. Soundararajan, M. Kandemir, A. Sivasubramaniam, C. Das","doi":"10.1145/2591971.2591973","DOIUrl":"https://doi.org/10.1145/2591971.2591973","url":null,"abstract":"As the demand for feature-rich mobile systems such as smartphones and tablets has outpaced other computing systems and is expected to continue at a faster rate, it is projected that SoCs with tens of cores and hundreds of IPs (or accelerator) will be designed to provide unprecedented level of features and functionality in future. Design of such mobile systems with required QoS and power budgets along with other design constraints will be a daunting task for computer architects since any ad hoc, piece-meal solution is unlikely to result in an optimal design. This requires early exploration of the complete design space to understand the system-level design trade-offs. To the best of our knowledge, there is no such publicly available tool to conduct a holistic evaluation of mobile platforms consisting of cores, IPs and system software.\u0000 This paper presents GemDroid, a comprehensive simulation infrastructure to address these concerns. GemDroid has been designed by integrating the Android open-source emulator for facilitating execution of mobile applications, the GEM5 core simulator for analyzing the CPU and memory centric designs, and models for several IPs to collectively study their impact on system-level performance and power. Analyzing a spectrum of applications with GemDroid, we observed that the memory subsystem is a vital cog in the mobile platform because, it needs to handle both core and IP traffic, which have very different characteristics. Consequently, we present a heterogeneous memory controller (HMC) design, where we divide the memory physically into two address regions, where the first region with one memory controller (MC) handles core-specific application data and the second region with another MC handles all IP related data. The proposed modifications to the memory controller design results in an average 25% reduction in execution time for CPU bound applications, up to 11% reduction in frame drops, and on average 17% reduction in CPU busy time for on-screen (IP bound) applications.","PeriodicalId":306456,"journal":{"name":"Measurement and Modeling of Computer Systems","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121953940","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}