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Wenchao Huang,&ast; Huaxin Sun,&ast; Yan Tang,&ast; Yan Luo, Hanxiong Liu Department of Cardiology, The Third People’s Hospital of Chengdu, College of Medicine, Southwest Jiaotong University, Chengdu, Sichuan, 610031, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Hanxiong Liu, Affiliated Hospital of Southwest Jiaotong University, The Third People’s Hospital of Chengdu, Chengdu Cardiovascular Disease Research Institute, 82 Qinglong St. Chengdu, Sichuan, People’s Republic of China, Tel +86 18897966045, Email clin999@163.comPurpose: To investigate the effect and comprehensive predictive value of the platelet-to-lymphocyte ratio (PLR) for long-term recurrence in patients with atrial fibrillation (AF) post ablation.Patients and Methods: We retrospectively analysed 638 consecutive AF patients who underwent ablation, including 302 (47.3%) with paroxysmal AF and 336 (52.7%) with nonparoxysmal AF. Patients were grouped into the recurrence and nonrecurrence groups.Results: After a mean follow-up of 15.1± 9.3 months, 175 patients (27.4%) with AF had long-term recurrence, including 114 patients (33.9%) with nonparoxysmal AF and 61 patients (20.2%) with paroxysmal AF. In the entire cohort and in patients with nonparoxysmal AF, but not in those with paroxysmal AF, the PLR was significantly higher in the recurrence group than in the nonrecurrence group (P< 0.05). After adjusting for the APPLE score, the PLR as a continuous variable independently predicted AF recurrence (hazard ratio [HR], 1.003; 95% confidence interval [CI], 1.001– 1.005; P< 0.01). The addition of the PLR to the APPLE score improved its predictive ability for recurrence (the C-statistic value increased from 0.645 to 0.675, P=0.02; the net reclassification improvement was 0.221, 95% CI 0.049– 0.394, P=0.01; and the integrated discrimination improvement was 0.029, 95% CI 0.013– 0.045, P< 0.01). For nonparoxysmal AF, the PLR

At present, millions of Ethereum smart contracts are created per year and attract financially motivated attackers. However, existing analyzers do not meet the need to precisely analyze the financial security of large numbers of contracts. In this paper, we propose and implement FASVERIF, an automated analyzer for fine-grained analysis of smart contracts' financial security. On the one hand, FASVERIF automatically generates models to be verified against security properties of smart contracts. On the other hand, our analyzer automatically generates the security properties, which is different from existing formal verifiers for smart contracts. As a result, FASVERIF can automatically process source code of smart contracts, and uses formal methods whenever possible to simultaneously maximize its accuracy. We evaluate FASVERIF on a vulnerabilities dataset by comparing it with other automatic tools. Our evaluation shows that FASVERIF greatly outperforms the representative tools using different technologies, with respect to accuracy and coverage of types of vulnerabilities.

Ternary blend has been an effective strategy for achieving high efficiency in organic solar cells (OSCs). Herein, a non-fullerene small molecule acceptor (C8-DTC) was synthesized and added to the PM6: Y6 system as a third component. By adding 10% of C8-DTC as the second acceptor in the PM6:Y6 system, an impressive power conversion efficiency of 17.52% was achieved with simultaneously increased open-circuit voltage, short-circuit current-density, and fill factor. The reduced voltage loss was due to the lowered non-radiative recombination loss in comparison with the binary device. It was also found that a small amount of C8-DTC in the PM6:Y6 blend resulted in enhanced charge separation and charge transport by providing possible extra channels of hole extraction. And the ternary system formed a good phase separation and favored bi-continuous transport network, which is more conducive to balance the electron and hole transport. The results indicate that the ternary system formed by C8-DTC as the third component is an effective method to improve the performance of the PM6:Y6 based OSCs., Funding Agencies|National Key Research and Development Program of China - MOST [2019YFA0705900]; National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [51820105003, 21734008, 61904181]; Basic and Applied Basic Research Major Program of Guangdong Province [2019B030302007]; Australian government through Australian Renewable Energy Agency (ARENA)Australian Renewable Energy Agency (ARENA)

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Despite significant development recently, improving the power conversion efficiency of organic photovoltaics (OPVs) is still an ongoing challenge to overcome. One of the prerequisites to achieving this goal is to enable efficient charge separation and small voltage losses at the same time. In this work, a facile synthetic strategy is reported, where optoelectronic properties are delicately tuned by the introduction of electron-deficient-core-based fused structure into non-fullerene acceptors. Both devices exhibited a low voltage loss of 0.57 V and high short-circuit current density of 22.0 mA cm(-2), resulting in high power conversion efficiencies of over 13.4%. These unconventional electron-deficient-core-based non-fullerene acceptors with near-infrared absorption lead to low non-radiative recombination losses in the resulting organic photovoltaics, contributing to a certified high power conversion efficiency of 12.6%., Funding Agencies|Air Force Office of Scientific Research (AFOSR) [FA2386-15-1-4108, FA9550e15-1e0610, FA9550-15-1-0333]; UC-Solar Program [MRPI 328368]; National Key Research & Development Projects of China [2017YFA0206600]; National Natural Science Foundation of China [21875286]; Science Fund for Distinguished Young Scholars of Hunan Province [2017JJ1029]; Swedish Energy Agency Energimyndigheten [2016-010174]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]

Despite significant development recently, improving the power conversion efficiency of organic photovoltaics (OPVs) is still an ongoing challenge to overcome. One of the prerequisites to achieving this goal is to enable efficient charge separation and small voltage losses at the same time. In this work, a facile synthetic strategy is reported, where optoelectronic properties are delicately tuned by the introduction of electron-deficient-core-based fused structure into non-fullerene acceptors. Both devices exhibited a low voltage loss of 0.57 V and high short-circuit current density of 22.0 mA cm(-2), resulting in high power conversion efficiencies of over 13.4%. These unconventional electron-deficient-core-based non-fullerene acceptors with near-infrared absorption lead to low non-radiative recombination losses in the resulting organic photovoltaics, contributing to a certified high power conversion efficiency of 12.6%., Funding Agencies|Air Force Office of Scientific Research (AFOSR) [FA2386-15-1-4108, FA9550e15-1e0610, FA9550-15-1-0333]; UC-Solar Program [MRPI 328368]; National Key Research & Development Projects of China [2017YFA0206600]; National Natural Science Foundation of China [21875286]; Science Fund for Distinguished Young Scholars of Hunan Province [2017JJ1029]; Swedish Energy Agency Energimyndigheten [2016-010174]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]

Despite significant development recently, improving the power conversion efficiency of organic photovoltaics (OPVs) is still an ongoing challenge to overcome. One of the prerequisites to achieving this goal is to enable efficient charge separation and small voltage losses at the same time. In this work, a facile synthetic strategy is reported, where optoelectronic properties are delicately tuned by the introduction of electron-deficient-core-based fused structure into non-fullerene acceptors. Both devices exhibited a low voltage loss of 0.57 V and high short-circuit current density of 22.0 mA cm-2, resulting in high power conversion efficiencies of over 13.4%. These unconventional electron-deficient-core-based non-fullerene acceptors with near-infrared absorption lead to low non-radiative recombination losses in the resulting organic photovoltaics, contributing to a certified high power conversion efficiency of 12.6%.

The original PDF version of this Article contained an error in the Additional information section, which incorrectly included the statement 'This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2019'. This has been removed from the PDF version of the Article. The HTML version was correct from the time of publication.

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Despite significant development recently, improving the power conversion efficiency of organic photovoltaics (OPVs) is still an ongoing challenge to overcome. One of the prerequisites to achieving this goal is to enable efficient charge separation and small voltage losses at the same time. In this work, a facile synthetic strategy is reported, where optoelectronic properties are delicately tuned by the introduction of electron-deficient-core-based fused structure into non-fullerene acceptors. Both devices exhibited a low voltage loss of 0.57 V and high short-circuit current density of 22.0 mA cm-2, resulting in high power conversion efficiencies of over 13.4%. These unconventional electron-deficient-core-based non-fullerene acceptors with near-infrared absorption lead to low non-radiative recombination losses in the resulting organic photovoltaics, contributing to a certified high power conversion efficiency of 12.6%.

The original PDF version of this Article contained an error in the Additional information section, which incorrectly included the statement 'This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2019'. This has been removed from the PDF version of the Article. The HTML version was correct from the time of publication.

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Despite significant development recently, improving the power conversion efficiency of organic photovoltaics (OPVs) is still an ongoing challenge to overcome. One of the prerequisites to achieving this goal is to enable efficient charge separation and small voltage losses at the same time. In this work, a facile synthetic strategy is reported, where optoelectronic properties are delicately tuned by the introduction of electron-deficient-core-based fused structure into non-fullerene acceptors. Both devices exhibited a low voltage loss of 0.57 V and high short-circuit current density of 22.0 mA cm(-2), resulting in high power conversion efficiencies of over 13.4%. These unconventional electron-deficient-core-based non-fullerene acceptors with near-infrared absorption lead to low non-radiative recombination losses in the resulting organic photovoltaics, contributing to a certified high power conversion efficiency of 12.6%., Funding Agencies|Air Force Office of Scientific Research (AFOSR) [FA2386-15-1-4108, FA9550e15-1e0610, FA9550-15-1-0333]; UC-Solar Program [MRPI 328368]; National Key Research & Development Projects of China [2017YFA0206600]; National Natural Science Foundation of China [21875286]; Science Fund for Distinguished Young Scholars of Hunan Province [2017JJ1029]; Swedish Energy Agency Energimyndigheten [2016-010174]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]

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Despite significant development recently, improving the power conversion efficiency of organic photovoltaics (OPVs) is still an ongoing challenge to overcome. One of the prerequisites to achieving this goal is to enable efficient charge separation and small voltage losses at the same time. In this work, a facile synthetic strategy is reported, where optoelectronic properties are delicately tuned by the introduction of electron-deficient-core-based fused structure into non-fullerene acceptors. Both devices exhibited a low voltage loss of 0.57 V and high short-circuit current density of 22.0 mA cm(-2), resulting in high power conversion efficiencies of over 13.4%. These unconventional electron-deficient-core-based non-fullerene acceptors with near-infrared absorption lead to low non-radiative recombination losses in the resulting organic photovoltaics, contributing to a certified high power conversion efficiency of 12.6%., Funding Agencies|Air Force Office of Scientific Research (AFOSR) [FA2386-15-1-4108, FA9550e15-1e0610, FA9550-15-1-0333]; UC-Solar Program [MRPI 328368]; National Key Research & Development Projects of China [2017YFA0206600]; National Natural Science Foundation of China [21875286]; Science Fund for Distinguished Young Scholars of Hunan Province [2017JJ1029]; Swedish Energy Agency Energimyndigheten [2016-010174]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]

Group oriented applications are getting more and more popular in mobile Internet and call for secure and efficient secret sharing (SS) scheme to meet their requirements. A $(t,n)$ threshold SS scheme divides a secret into $n$ shares such that any $t$ or more than $t$ shares can recover the secret while less than $t$ shares cannot. However, an adversary, even without a valid share, may obtain the secret by impersonating a shareholder to recover the secret with $t$ or more legal shareholders. Therefore, this paper uses linear code to propose a threshold changeable secret sharing (TCSS) scheme, in which threshold should increase from $t$ to the exact number of all participants during secret reconstruction. The scheme does not depend on any computational assumption and realizes asymptotically perfect security. Furthermore, based on the proposed TCSS scheme, a group authentication scheme is constructed, which allows a group user to authenticate whether all users are legal group members at once and thus provides efficient and flexible m-to-m authentication for group oriented applications.

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Despite significant development recently, improving the power conversion efficiency of organic photovoltaics (OPVs) is still an ongoing challenge to overcome. One of the prerequisites to achieving this goal is to enable efficient charge separation and small voltage losses at the same time. In this work, a facile synthetic strategy is reported, where optoelectronic properties are delicately tuned by the introduction of electron-deficient-core-based fused structure into non-fullerene acceptors. Both devices exhibited a low voltage loss of 0.57 V and high short-circuit current density of 22.0 mA cm(-2), resulting in high power conversion efficiencies of over 13.4%. These unconventional electron-deficient-core-based non-fullerene acceptors with near-infrared absorption lead to low non-radiative recombination losses in the resulting organic photovoltaics, contributing to a certified high power conversion efficiency of 12.6%., Funding Agencies|Air Force Office of Scientific Research (AFOSR) [FA2386-15-1-4108, FA9550e15-1e0610, FA9550-15-1-0333]; UC-Solar Program [MRPI 328368]; National Key Research & Development Projects of China [2017YFA0206600]; National Natural Science Foundation of China [21875286]; Science Fund for Distinguished Young Scholars of Hunan Province [2017JJ1029]; Swedish Energy Agency Energimyndigheten [2016-010174]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]

Incorporating narrow-bandgap near-infrared absorbers as the third component in a donor/acceptor binary blend is a new strategy to improve the power conversion efficiency (PCE) of organic photovoltaics (OPV). However, there are two main restrictions: potential charge recombination in the narrow-gap material and miscompatibility between each component. The optimized design is to employ a third component (structurally similar to the donor or acceptor) with a lowest unoccupied molecular orbital (LUMO) energy level similar to the acceptor and a highest occupied molecular orbital (HOMO) energy level similar to the donor. In this design, enhanced absorption of the active layer and enhanced charge transfer can be realized without breaking the optimized morphology of the active layer. Herein, in order to realize this design, two new narrow-bandgap nonfullerene acceptors with suitable energy levels and chemical structures are designed, synthesized, and employed as the third component in the donor/acceptor binary blend, which boosts the PCE of OPV to 11.6%.

Incorporating narrow-bandgap near-infrared absorbers as the third component in a donor/acceptor binary blend is a new strategy to improve the power conversion efficiency (PCE) of organic photovoltaics (OPV). However, there are two main restrictions: potential charge recombination in the narrow-gap material and miscompatibility between each component. The optimized design is to employ a third component (structurally similar to the donor or acceptor) with a lowest unoccupied molecular orbital (LUMO) energy level similar to the acceptor and a highest occupied molecular orbital (HOMO) energy level similar to the donor. In this design, enhanced absorption of the active layer and enhanced charge transfer can be realized without breaking the optimized morphology of the active layer. Herein, in order to realize this design, two new narrow-bandgap nonfullerene acceptors with suitable energy levels and chemical structures are designed, synthesized, and employed as the third component in the donor/acceptor binary blend, which boosts the PCE of OPV to 11.6%.

Android users are now suffering severe threats from unwanted behaviors of various apps. The analysis of apps' audit logs is one of the essential methods for some device manufacturers to unveil the underlying malice within apps. We propose and implement AppAngio, a novel system that reveals contextual information in Android app behaviors by API-level audit logs. Our goal is to help analysts of device manufactures understand what has happened on users' devices and facilitate the identification of the malice within apps. The key module of AppAngio is identifying the path matched with the logs on the app's control-flow graph (CFG). The challenge, however, is that the limited-quantity logs may incur high computational complexity in the log matching, where there are a large number of candidates caused by the coupling relation of successive logs. To address the challenge, we propose a divide and conquer strategy that precisely positions the nodes matched with log records on the corresponding CFGs and connects the nodes with as few backtracks as possible. Our experiments show that AppAngio reveals the contextual information of behaviors in real-world apps. Moreover, the revealed results assist the analysts in identifying malice of app behaviors and complement existing analysis schemes. Meanwhile, AppAngio incurs negligible performance overhead on the Android device., Comment: Accepted by TIFS

Current formal approaches have been successfully used to find design flaws in many security protocols. However, it is still challenging to automatically analyze protocols due to their large or infinite state spaces. In this paper, we propose a novel framework that can automatically verifying security protocols without any human intervention. Experimental results show that SmartVerif automatically verifies security protocols that cannot be automatically verified by existing approaches. The case study also validates the effectiveness of our dynamic strategy., Comment: arXiv admin note: text overlap with arXiv:1403.1142, arXiv:1703.00426 by other authors

Multi-dimensional time series is playing an increasingly important role in the “big data” era, one noticeable representative being the pervasive trajectory data. Numerous applications of multi-dimensional time series all require to find similar time series of a given one, and regarding this purpose, Dynamic Time Warping (DTW) is the most widely used distance measure. Due to the high computation overhead of DTW, many lower bounding methods have been proposed to speed up similarity search. However, almost all the existing lower bounds are for general time series, which means they do not take advantage of the unique characteristics of higher dimensional time series. In this paper, we introduce a new lower bound for constrained DTW on multi-dimensional time series to achieve fast similarity search. The key observation is that when the time series is multi-dimensional, it can be rotated around the time axis, which helps to minimize the bounding envelope, thus improve the tightness, and in consequence the pruning power, of the lower bound. The experiment result on real world datasets demonstrates that our proposed method achieves faster similarity search than state-of-the-art techniques based on DTW.

Multi-dimensional time series is playing an increasingly important role in the “big data” era, one noticeable representative being the pervasive trajectory data. Numerous applications of multi-dimensional time series all require to find similar time series of a given one, and regarding this purpose, Dynamic Time Warping (DTW) is the most widely used distance measure. Due to the high computation overhead of DTW, many lower bounding methods have been proposed to speed up similarity search. However, almost all the existing lower bounds are for general time series, which means they do not take advantage of the unique characteristics of higher dimensional time series. In this paper, we introduce a new lower bound for constrained DTW on multi-dimensional time series to achieve fast similarity search. The key observation is that when the time series is multi-dimensional, it can be rotated around the time axis, which helps to minimize the bounding envelope, thus improve the tightness, and in consequence the pruning power, of the lower bound. The experiment result on real world datasets demonstrates that our proposed method achieves faster similarity search than state-of-the-art techniques based on DTW.

Multi-dimensional time series is playing an increasingly important role in the “big data” era, one noticeable representative being the pervasive trajectory data. Numerous applications of multi-dimensional time series all require to find similar time series of a given one, and regarding this purpose, Dynamic Time Warping (DTW) is the most widely used distance measure. Due to the high computation overhead of DTW, many lower bounding methods have been proposed to speed up similarity search. However, almost all the existing lower bounds are for general time series, which means they do not take advantage of the unique characteristics of higher dimensional time series. In this paper, we introduce a new lower bound for constrained DTW on multi-dimensional time series to achieve fast similarity search. The key observation is that when the time series is multi-dimensional, it can be rotated around the time axis, which helps to minimize the bounding envelope, thus improve the tightness, and in consequence the pruning power, of the lower bound. The experiment result on real world datasets demonstrates that our proposed method achieves faster similarity search than state-of-the-art techniques based on DTW.

We propose and implement a novel relative positioning system, WalkieLokie, to enable more kinds of Augmented Reality applications, e.g., virtual shopping guide, virtual business card sharing. WalkieLokie calculates the distance and direction between an inquiring user and the corresponding target. It only requires a dummy speaker binding to the target and broadcasting inaudible acoustic signals. Then the user walking around can obtain the position using a smart device. The key insight is that when a user walks, the distance between the smart device and the speaker changes; and the pattern of displacement (variance of distance) corresponds to the relative position. We use a second-order phase locked loop to track the displacement and further estimate the position. To enhance the accuracy and robustness of our strategy, we propose a synchronization mechanism to synthesize all estimation results from different timeslots. We show that the mean error of ranging and direction estimation is 0.63m and 2.46 degrees respectively, which is accurate even in case of virtual business card sharing. Furthermore, in the shopping mall where the environment is quite severe, we still achieve high accuracy of positioning one dummy speaker, and the mean position error is 1.28m., Comment: 14 pages

In this paper, we propose a novel indoor localization scheme that exploits ubiquitous visible lights, which are necessarily and densely deployed in almost all indoor environments. We unveil two phenomena of lights available for positioning: 1) the light strength varies according to different light sources, which can be easily detected by light sensors embedded in COTS devices (e.g., smart-phone, smart-glass and smart-watch); 2) the light strength is stable in different times of the day thus exploiting it can avoid frequent site-survey and database maintenance. Hence, a user could locate oneself by differentiating the light source of received light strength (RLS). However, different from existing positioning systems that exploit special LEDs, ubiquitous visible lights lack fingerprints that can uniquely identify the light source, which results in an ambiguity problem that an RLS may correspond to multiple positions. Moreover, RLS is not only determined by device's position, but also seriously affected by its orientation, which causes great complexity in site-survey. To address these challenges, we first propose and validate a realistic light strength model that can attributes RLS to arbitrary positions with heterogenous orientations. This model is further perfected by taking account of the device diversity, influence of multiple light sources and shading of obstacles. Then we design a localizing scheme that harness user's mobility to generate spatial-related RLS to tackle the position-ambiguity problem of a single RLS, which is robust against sunlight interference, shading effect of human-body and unpredictable behaviours (e.g., put the device in pocket) of user. Experiment results show that our scheme achieves mean accuracy $1.93$m and $1.98$m in office ($720m^2$) and library scenario ($960m^2$) respectively.

With the rapid development of MANET, secure and practical authentication is becoming increasingly important. The existing works perform the research from two aspects, i.e., (a)secure key division and distributed storage, (b)secure distributed authentication. But there still exist several unsolved problems. Specifically, it may suffer from cheating problems and fault authentication attack, which can result in authentication failure and DoS attack towards authentication service. Besides, most existing schemes are not with satisfactory efficiency due to exponential arithmetic based on Shamir's scheme. In this paper, we explore the property of verifiable secret sharing(VSS) schemes with Chinese Remainder Theorem (CRT), then propose a secret key distributed storage scheme based on CRT-VSS and trusted computing for MANET. Specifically, we utilize trusted computing technology to solve two existing cheating problems in secret sharing area before. After that, we do the analysis of homomorphism property with CRT-VSS and design the corresponding shares-product sharing scheme with better concision. On such basis, a secure distributed Elliptic Curve-Digital Signature Standard signature (ECC-DSS) authentication scheme based on CRT-VSS scheme and trusted computing is proposed. Furthermore, as an important property of authentication scheme, we discuss the refreshing property of CRT-VSS and do thorough comparisons with Shamir's scheme. Finally, we provide formal guarantees towards our schemes proposed in this paper., Comment: under submission

In recent years, due to the wide applications of uncertain data (e.g., noisy data), uncertain frequent itemsets (UFI) mining over uncertain databases has attracted much attention, which differs from the corresponding deterministic problem from the generalized definition and resolutions. As the most costly task in association rule mining process, it has been shown that outsourcing this task to a service provider (e.g.,the third cloud party) brings several benefits to the data owner such as cost relief and a less commitment to storage and computational resources. However, the correctness integrity of mining results can be corrupted if the service provider is with random fault or not honest (e.g., lazy, malicious, etc). Therefore, in this paper, we focus on the integrity and verification issue in UFI mining problem during outsourcing process, i.e., how the data owner verifies the mining results. Specifically, we explore and extend the existing work on deterministic FI outsourcing verification to uncertain scenario. For this purpose, We extend the existing outsourcing FI mining work to uncertain area w.r.t. the two popular UFI definition criteria and the approximate UFI mining methods. Specifically, We construct and improve the basic/enhanced verification scheme with such different UFI definition respectively. After that, we further discuss the scenario of existing approximation UFP mining, where we can see that our technique can provide good probabilistic guarantees about the correctness of the verification. Finally, we present the comparisons and analysis on the schemes proposed in this paper., Comment: under submission

We propose and implement a novel indoor localization scheme, Swadloon, built upon an accurate acoustic direction finding. Swadloon leverages sensors of the smartphone without the requirement of any specialized devices. The scheme Swadloon does not rely on any fingerprints and is very easy to use: a user only needs to shake the phone for a short duration before walking and localization. Our Swadloon design exploits a key observation: the relative shift and velocity of the phone-shaking movement corresponds to the subtle phase and frequency shift of the Doppler effects experienced in the received acoustic signal by the phone. A novel method is designed to derive the direction from the phone to the acoustic source by combining the velocity calculated from the subtle Doppler shift with the one from the inertial sensors of the phone. Then a real-time precise localization and tracking is enabled by using a few anchor speakers with known locations. Major challenges in implementing Swadloon are to measure the frequency shift precisely and to estimate the shaking velocity accurately when the speed of phone-shaking is low and changes arbitrarily. We propose rigorous methods to address these challenges, then design and deploy Swadloon in several floors of an indoor building each with area about 2000m^2. Our extensive experiments show that the mean error of direction finding is around 2.1 degree when the acoustic source is within the range of 32m. For indoor localization, the 90-percentile errors are under 0.92m, while the maximum error is 1.73m and the mean is about 0.5m. For real-time tracking, the errors are within 0.4m for walks of 51m., Comment: Under submission