Radio-based passive-object sensing can enable a new form of pervasive user-computer interface. Prior work has employed various wireless signal features to sense objects under a set of predefined, coarse motion patterns. But an operational UI, like a trackpad, often needs to identify fine-grained, arbitrary motion. This paper explores the feasibility of tracking a passive writing object (e.g., pen) at sub-centimeter precision. We approach this goal through a practical design, mTrack, which uses highly-directional 60 GHz millimeter-wave radios as key enabling technology. mTrack runs a discrete beam scanning mechanism to pinpoint the object's initial location, and tracks its trajectory using a signal-phase based model. In addition, mTrack incorporates novel mechanisms to suppress interference from background reflections, taking advantage of the short wavelength of 60 GHz signals. We prototype mTrack and evaluate its performance on a 60 GHz reconfigurable radio platform. Experimental results demonstrate that mTrack can locate/track a pen with 90-percentile error below 8 mm, enabling new applications such as wireless transcription and virtual trackpad.
{"title":"mTrack: High-Precision Passive Tracking Using Millimeter Wave Radios","authors":"Teng Wei, Xinyu Zhang","doi":"10.1145/2789168.2790113","DOIUrl":"https://doi.org/10.1145/2789168.2790113","url":null,"abstract":"Radio-based passive-object sensing can enable a new form of pervasive user-computer interface. Prior work has employed various wireless signal features to sense objects under a set of predefined, coarse motion patterns. But an operational UI, like a trackpad, often needs to identify fine-grained, arbitrary motion. This paper explores the feasibility of tracking a passive writing object (e.g., pen) at sub-centimeter precision. We approach this goal through a practical design, mTrack, which uses highly-directional 60 GHz millimeter-wave radios as key enabling technology. mTrack runs a discrete beam scanning mechanism to pinpoint the object's initial location, and tracks its trajectory using a signal-phase based model. In addition, mTrack incorporates novel mechanisms to suppress interference from background reflections, taking advantage of the short wavelength of 60 GHz signals. We prototype mTrack and evaluate its performance on a 60 GHz reconfigurable radio platform. Experimental results demonstrate that mTrack can locate/track a pen with 90-percentile error below 8 mm, enabling new applications such as wireless transcription and virtual trackpad.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124161679","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}
Mobile web browsing is experienced slow because of the limited rendering capability of the mobile devices, wireless latency, and incremental rendering of the page or resource loading. The browser renders resources in between two consecutive resource downloads. However, during this period, the wireless interfaces consume energy doing nothing useful. In this work, we measure the performance of SPDY for mobile web browsing. We demonstrate that mobile devices waste energy by keeping the wireless network interface idle between consecutive resource downloads. We next show that by identifying the embedded resources in a web page and downloading those resources in parallel at the very beginning can reduce the small idle periods and thus energy consumption by 20-50%, depending on the wireless network type.
{"title":"Poster: Extremely Parallel Resource Pre-Fetching for Energy Optimized Mobile Web Browsing","authors":"M. A. Hoque, S. Tarkoma, Tuikku Anttila","doi":"10.1145/2789168.2795167","DOIUrl":"https://doi.org/10.1145/2789168.2795167","url":null,"abstract":"Mobile web browsing is experienced slow because of the limited rendering capability of the mobile devices, wireless latency, and incremental rendering of the page or resource loading. The browser renders resources in between two consecutive resource downloads. However, during this period, the wireless interfaces consume energy doing nothing useful. In this work, we measure the performance of SPDY for mobile web browsing. We demonstrate that mobile devices waste energy by keeping the wireless network interface idle between consecutive resource downloads. We next show that by identifying the embedded resources in a web page and downloading those resources in parallel at the very beginning can reduce the small idle periods and thus energy consumption by 20-50%, depending on the wireless network type.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115908384","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. Nikaein, R. Knopp, Lionel Gauthier, Eryk Schiller, T. Braun, D. Pichon, C. Bonnet, F. Kaltenberger, D. Nussbaum
Commoditization and virtualization of wireless networks are changing the economics of mobile networks to help network providers (e.g., MNO, MVNO) move from proprietary and bespoke hardware and software platforms toward an open, cost-effective, and flexible cellular ecosystem. In addition, rich and innovative local services can be efficiently created through cloudification by leveraging the existing infrastructure. In this work, we present RANaaS, which is a cloudified radio access network delivered as a service. RANaaS provides the service life-cycle of an on-demand, elastic, and pay as you go 3GPP RAN instantiated on top of the cloud infrastructure. We demonstrate an example of real-time cloudified LTE network deployment using the OpenAirInterface LTE implementation and OpenStack running on commodity hardware as well as the flexibility and performance of the platform developed.
{"title":"Demo: Closer to Cloud-RAN: RAN as a Service","authors":"N. Nikaein, R. Knopp, Lionel Gauthier, Eryk Schiller, T. Braun, D. Pichon, C. Bonnet, F. Kaltenberger, D. Nussbaum","doi":"10.1145/2789168.2789178","DOIUrl":"https://doi.org/10.1145/2789168.2789178","url":null,"abstract":"Commoditization and virtualization of wireless networks are changing the economics of mobile networks to help network providers (e.g., MNO, MVNO) move from proprietary and bespoke hardware and software platforms toward an open, cost-effective, and flexible cellular ecosystem. In addition, rich and innovative local services can be efficiently created through cloudification by leveraging the existing infrastructure. In this work, we present RANaaS, which is a cloudified radio access network delivered as a service. RANaaS provides the service life-cycle of an on-demand, elastic, and pay as you go 3GPP RAN instantiated on top of the cloud infrastructure. We demonstrate an example of real-time cloudified LTE network deployment using the OpenAirInterface LTE implementation and OpenStack running on commodity hardware as well as the flexibility and performance of the platform developed.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123852468","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 presents FreeBee, which enables direct unicast as well as cross-technology/channel broadcast among three popular wireless technologies: WiFi, ZigBee, and Bluetooth. Our design aims to shed the light on the opportunities that cross-technology communication has to offer including, but not limited to, cross-technology cooperation and coordination. The key concept of FreeBee is to modulate symbol messages by shifting the timing of periodic beacon frames already mandatory for wireless standards without incurring extra traffic. Such a generic cross-technology design consumes zero additional bandwidth, allowing continuous broadcast to safely reach mobile and/or duty-cycled devices. A new emph{interval multiplexing} technique is proposed to enable concurrent broadcasts from multiple senders or boost the transmission rate of a single sender. Theoretical and experimental exploration reveals that FreeBee offers a reliable symbol delivery under a second and supports mobility of 30mph and low duty-cycle operations of under 5%.
{"title":"FreeBee: Cross-technology Communication via Free Side-channel","authors":"S. Kim, T. He","doi":"10.1145/2789168.2790098","DOIUrl":"https://doi.org/10.1145/2789168.2790098","url":null,"abstract":"This paper presents FreeBee, which enables direct unicast as well as cross-technology/channel broadcast among three popular wireless technologies: WiFi, ZigBee, and Bluetooth. Our design aims to shed the light on the opportunities that cross-technology communication has to offer including, but not limited to, cross-technology cooperation and coordination. The key concept of FreeBee is to modulate symbol messages by shifting the timing of periodic beacon frames already mandatory for wireless standards without incurring extra traffic. Such a generic cross-technology design consumes zero additional bandwidth, allowing continuous broadcast to safely reach mobile and/or duty-cycled devices. A new emph{interval multiplexing} technique is proposed to enable concurrent broadcasts from multiple senders or boost the transmission rate of a single sender. Theoretical and experimental exploration reveals that FreeBee offers a reliable symbol delivery under a second and supports mobility of 30mph and low duty-cycle operations of under 5%.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127824379","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}
Line-of-Sight blockage by human body is a severe challenge to enable robust 60 GHz directional links. Beamsteering is one feasible solution to overcome this problem by electronically steering phased-array beam towards Non-Line-of-Sight. However, effectiveness of beamsteering depends on the link deployment and a lack of assessment of steering effectiveness may render the link completely blacked-out during human blockage. In this poster, we propose a new technique called BeamScope, that predicts best possible location for a randomly deployed link in an indoor environment without the need of any explicit war-driving. BeamScope first characterizes the environment exploiting measurement from the randomly deployed reference location and then predicts the performance in unobserved locations to suggest a possible re-deployment. The environment characterization is captured through a novel metric and prediction is achieved via how this metric is shared between the reference location and unobserved locations. Our preliminary results show promising accuracy of identifying the best possible alternate location for 60 GHz link to achieve a robust connection during human blockage.
{"title":"Poster: Scoping Environment to Assist 60 GHz Link Deployment","authors":"Sanjib Sur, Xinyu Zhang","doi":"10.1145/2789168.2795182","DOIUrl":"https://doi.org/10.1145/2789168.2795182","url":null,"abstract":"Line-of-Sight blockage by human body is a severe challenge to enable robust 60 GHz directional links. Beamsteering is one feasible solution to overcome this problem by electronically steering phased-array beam towards Non-Line-of-Sight. However, effectiveness of beamsteering depends on the link deployment and a lack of assessment of steering effectiveness may render the link completely blacked-out during human blockage. In this poster, we propose a new technique called BeamScope, that predicts best possible location for a randomly deployed link in an indoor environment without the need of any explicit war-driving. BeamScope first characterizes the environment exploiting measurement from the randomly deployed reference location and then predicts the performance in unobserved locations to suggest a possible re-deployment. The environment characterization is captured through a novel metric and prediction is achieved via how this metric is shared between the reference location and unobserved locations. Our preliminary results show promising accuracy of identifying the best possible alternate location for 60 GHz link to achieve a robust connection during human blockage.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"187 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127589962","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}
Xiaomeng Chen, Abhilash Jindal, Ning Ding, Y. C. Hu, M. Gupta, R. Vannithamby
As new iterations of more powerful and better connected smartphones emerge, their limited battery life remains a leading factor adversely affecting the mobile experience of millions of smartphone users. While it is well-known that many apps can drain battery even while running in background, there has not been any study that quantifies the extent and severity of such background energy drain for users in the wild. To extend battery life, various new features are being incorporated within the phone, one of them being preventing applications from running in background, i.e., when the screen is off, but their impact is largely unknown. This paper makes several contributions. First, we present a large-scale measurement study that performs an in-depth analysis of the activities of various apps running in background on thousands of phones in the wild. Second, we quantify the amount of battery drain by all such background activities and possible energy saving. Third, we develop a metric to measure the usefulness of background activities that is personalized to each user. Finally, we present a system called HUSH (screen-off optimizer) that monitors the metric online and automatically identifies and suppresses background activities during screen-off periods that are not useful to the user experience. In doing so, our proposed HUSH saves screen-off energy of smartphones by 15.7% on average while incurring minimal impact on the user experience with the apps.
{"title":"Smartphone Background Activities in the Wild: Origin, Energy Drain, and Optimization","authors":"Xiaomeng Chen, Abhilash Jindal, Ning Ding, Y. C. Hu, M. Gupta, R. Vannithamby","doi":"10.1145/2789168.2790107","DOIUrl":"https://doi.org/10.1145/2789168.2790107","url":null,"abstract":"As new iterations of more powerful and better connected smartphones emerge, their limited battery life remains a leading factor adversely affecting the mobile experience of millions of smartphone users. While it is well-known that many apps can drain battery even while running in background, there has not been any study that quantifies the extent and severity of such background energy drain for users in the wild. To extend battery life, various new features are being incorporated within the phone, one of them being preventing applications from running in background, i.e., when the screen is off, but their impact is largely unknown. This paper makes several contributions. First, we present a large-scale measurement study that performs an in-depth analysis of the activities of various apps running in background on thousands of phones in the wild. Second, we quantify the amount of battery drain by all such background activities and possible energy saving. Third, we develop a metric to measure the usefulness of background activities that is personalized to each user. Finally, we present a system called HUSH (screen-off optimizer) that monitors the metric online and automatically identifies and suppresses background activities during screen-off periods that are not useful to the user experience. In doing so, our proposed HUSH saves screen-off energy of smartphones by 15.7% on average while incurring minimal impact on the user experience with the apps.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126005128","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 applicability of IEEE 802.11ac for entertainment low-latency show control systems (to orchestrate free-riding vehicles in a theme-park environment) by experimentally characterizing the indoor throughput and jitter performance of 802.11ac using statistical analysis. 802.11ac is the successor of 802.11n that provides higher throughput by incorporating wider channels, more spatial streams and denser modulation. We show that multiple linear regression provides valuable insight in the influence of 802.11ac's independent features and their combinations on performance, for various links and interference scenarios. Finally, we show that 802.11ac could be used for not only delivering high throughput for multimedia streaming but also supports applications requiring minimal jitter variance in the setup investigated.
{"title":"Poster: Regression-based Characterization of 802.11ac Indoor Performance","authors":"Edgar Costa Molero, Lito Kriara, T. Gross","doi":"10.1145/2789168.2795173","DOIUrl":"https://doi.org/10.1145/2789168.2795173","url":null,"abstract":"We investigate the applicability of IEEE 802.11ac for entertainment low-latency show control systems (to orchestrate free-riding vehicles in a theme-park environment) by experimentally characterizing the indoor throughput and jitter performance of 802.11ac using statistical analysis. 802.11ac is the successor of 802.11n that provides higher throughput by incorporating wider channels, more spatial streams and denser modulation. We show that multiple linear regression provides valuable insight in the influence of 802.11ac's independent features and their combinations on performance, for various links and interference scenarios. Finally, we show that 802.11ac could be used for not only delivering high throughput for multimedia streaming but also supports applications requiring minimal jitter variance in the setup investigated.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131788341","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}
Recent research has proposed swarming protocols as a possible approach to offload the Internet infrastructure when some content can be shared by several users. However, simulations have been generally used as experimental means. Instead, we present an application platform that allows a rapid development and testing of swarming protocols using off-the-shelf smartphones.
{"title":"Poster: Mobile Data Offloading Testbed","authors":"Matteo Pozza, C. Palazzi, Armir Bujari","doi":"10.1145/2789168.2795159","DOIUrl":"https://doi.org/10.1145/2789168.2795159","url":null,"abstract":"Recent research has proposed swarming protocols as a possible approach to offload the Internet infrastructure when some content can be shared by several users. However, simulations have been generally used as experimental means. Instead, we present an application platform that allows a rapid development and testing of swarming protocols using off-the-shelf smartphones.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129689803","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}
R. Aguiar, N. Benhabiles, Tobias Pfeiffer, P. Rodriguez, H. Viswanathan, Jia Wang, Hui Zang
The concepts of Big Data have became intertwined with those of the Internet of Things, creating mental pictures of a fully connected, all-encompassing, cyber-physical world, where each and every object will contribute with information to a "fully aware" society. Academic works are presenting this as the natural evolution for our current technologies. The panel looks at these promises from the hard perspective of reality: what is being done, how much it cost, what needs to be developed, and what can be expected in the near and mid-term.
{"title":"Big Data, IoT, .... Buzz Words for Academia or Reality for Industry?","authors":"R. Aguiar, N. Benhabiles, Tobias Pfeiffer, P. Rodriguez, H. Viswanathan, Jia Wang, Hui Zang","doi":"10.1145/2789168.2802150","DOIUrl":"https://doi.org/10.1145/2789168.2802150","url":null,"abstract":"The concepts of Big Data have became intertwined with those of the Internet of Things, creating mental pictures of a fully connected, all-encompassing, cyber-physical world, where each and every object will contribute with information to a \"fully aware\" society. Academic works are presenting this as the natural evolution for our current technologies. The panel looks at these promises from the hard perspective of reality: what is being done, how much it cost, what needs to be developed, and what can be expected in the near and mid-term.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131326478","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}
Bingxian Lu, Zhicheng Zeng, Lei Wang, B. Peck, D. Qiao
In recent years, Wi-Fi has seen extraordinary growth; however, due to the cost, performance and security issues, many Wi-Fi hotspot owners would like to restrict the network access only to individuals inside the physical property. Unfortunately, due to the nature of wireless, this is difficult to accomplish, especially with the off-the-shelf omni-antenna devices. In this work, we develop and implement CLaWa, a Crowdsourced Location Aware Wi-Fi Access Control scheme to address this challenge. Our system is based on observations of differing characteristics of physical layer information across physical boundaries such as walls and corners. CLaWa crowdsources both channel state information (CSI) and received signal strength (RSS) of already validated users to classify future users. We have also selected an appropriate machine learning algorithm for CLaWa. Evaluation results show that CLaWa can identify the boundary around a given area precisely, thus granting network access only to users inside the area while not validating users outside the boundary. Compared to indoor localization schemes, CLaWa is a lightweight solution which does not require expensive localization operations.
{"title":"Poster: Crowdsourced Location Aware Wi-Fi Access Control","authors":"Bingxian Lu, Zhicheng Zeng, Lei Wang, B. Peck, D. Qiao","doi":"10.1145/2789168.2795183","DOIUrl":"https://doi.org/10.1145/2789168.2795183","url":null,"abstract":"In recent years, Wi-Fi has seen extraordinary growth; however, due to the cost, performance and security issues, many Wi-Fi hotspot owners would like to restrict the network access only to individuals inside the physical property. Unfortunately, due to the nature of wireless, this is difficult to accomplish, especially with the off-the-shelf omni-antenna devices. In this work, we develop and implement CLaWa, a Crowdsourced Location Aware Wi-Fi Access Control scheme to address this challenge. Our system is based on observations of differing characteristics of physical layer information across physical boundaries such as walls and corners. CLaWa crowdsources both channel state information (CSI) and received signal strength (RSS) of already validated users to classify future users. We have also selected an appropriate machine learning algorithm for CLaWa. Evaluation results show that CLaWa can identify the boundary around a given area precisely, thus granting network access only to users inside the area while not validating users outside the boundary. Compared to indoor localization schemes, CLaWa is a lightweight solution which does not require expensive localization operations.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116666566","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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