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1. Self-Calibrating Indoor Trajectory Tracking System Using Distributed Monostatic Radars For Large Scale Deployment

   https://doi.org/10.1145/3563357.3564078  

   Xie, Zongxing; Ye, Fan (January 2022, ACM International Conference on Systems for Energy-Efficient Buildings, Cities, and Transportation)

   24/7 continuous recording of in-home daily trajectories is informative for health status assessment (e.g., monitoring Alzheimer’s, dementia based on behavior patterns). Indoor device-free localization/tracking are ideal because no user efforts on wearing devices are needed. However, prior work mainly focused on improving the localization accuracy. They relied on well-calibrated sensor placements, which require hours of intensive manual setup and respective expertise, feasible only at small scale and by mostly re- searchers themselves. Scaling the deployments to tens or hundreds of real homes, however, would incur prohibitive manual efforts, and become infeasible for layman users. We present SCALING, a plug-and-play indoor trajectory monitoring system that layman users can easily setup by walking a one-minute loop trajectory after placing radar nodes on walls. It uses a self calibrating algorithm that estimates sensor locations through their distance measurements to the person walking the trajectory, a trivial effort without taxing layman users physically or cognitively. We evaluate SCALING via simulations and two testbeds (in lab and home configurations of sizes 3 × 6 sq m and 4.5 × 8.5 sq m). Experimental results demonstrate that SCALING outperformed the baseline using the approximate multidimensional scaling (MDS, the most relevant method in the context of self calibration) by 3.5 m/1.6 m in 80-percentile error of self calibration and tracking,respectively.Notably,only1% degradation in performance has been observed with SCALING compared to the classical multilateration with known sensor locations (anchors), which costs hours of intensive calibrating effort. 

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2. Poster Abstract: Scaling Device-free Indoor Tracking based on Self Calibration

   Xie, Zongxing; Ye, Fan (January 2022, ACM Conference on Embedded Networked Sensor Systems)

   The democratization of indoor tracking systems lays the ground- work for a wide spectrum of smart home applications. While prior work on RF-based device-free localization/tracking have shown preferable features and promising results, they heavily relied on well-calibrated sensor placements, which require hours of intensive manual setup and respective expertise, making it prohibitively expensive to scale deployments to wide range (e.g., tens or hundreds of real homes). We propose SCALING, a plug-and-play indoor tracking system, of which the key enabler is a self calibrating algorithm that estimates the distributed sensor locations through their distance measurements to a person walking a trajectory, a trivial effort without taxing layman users physically or cognitively. We have experimentally evaluated SCALING via real world testbeds and shown an 80-percentile tracking accuracy of 40.5 cm, only 1% degradation compared to the classical multilateration with known sensor locations (anchors), which costs hours of intensive calibrating effort. 

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3. Remarks on the existence of minimal models of log canonical generalized pairs

   https://doi.org/10.1007/s00209-024-03489-6  

   Tsakanikas, Nikolaos; Xie, Lingyao (April 2024, Mathematische Zeitschrift)

   Abstract Given an NQC log canonical generalized pair$$(X,B+M)$$ $(X,B+M)$whose underlying varietyXis not necessarily$$\mathbb {Q}$$ $Q$-factorial, we show that one may run a$$(K_X+B+M)$$ $(K_X+B+M)$-MMP with scaling of an ample divisor which terminates, provided that$$(X,B+M)$$ $(X,B+M)$has a minimal model in a weaker sense or that$$K_X+B+M$$ $K_X+B+M$is not pseudo-effective. We also prove the existence of minimal models of pseudo-effective NQC log canonical generalized pairs under various additional assumptions, for instance when the boundary contains an ample divisor. 

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4. Regularity of area minimizing currents mod p

   https://doi.org/10.1007/s00039-020-00546-0  

   De Lellis, Camillo; Hirsch, Jonas; Marchese, Andrea; Stuvard, Salvatore (October 2020, Geometric and Functional Analysis)

   Abstract We establish a first general partial regularity theorem for area minimizing currents$${\mathrm{mod}}(p)$$ $\mathrm{mod}\left(p\right)$, for everyp, in any dimension and codimension. More precisely, we prove that the Hausdorff dimension of the interior singular set of anm-dimensional area minimizing current$${\mathrm{mod}}(p)$$ $\mathrm{mod}\left(p\right)$cannot be larger than$$m-1$$ $m-1$. Additionally, we show that, whenpis odd, the interior singular set is$$(m-1)$$ $(m-1)$-rectifiable with locally finite$$(m-1)$$ $(m-1)$-dimensional measure. 

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5. More on codes for combinatorial composite DNA

   https://doi.org/10.1007/s10623-025-01634-8  

   Ye, Zuo; Sabary, Omer; Gabrys, Ryan; Yaakobi, Eitan; Elishco, Ohad (May 2025, Designs, Codes and Cryptography)

   Abstract In this paper, we focus on constructing unique-decodable and list-decodable codes for the recently studied (t, e)-composite-asymmetric error-correcting codes ((t, e)-CAECCs). Let$$\mathcal {X}$$ $X$be an$$m \times n$$ $m\times n$binary matrix in which each row has Hamming weightw. If at mosttrows of$$\mathcal {X}$$ $X$contain errors, and in each erroneous row, there are at mosteoccurrences of$$1 \rightarrow 0$$ $1\to 0$errors, we say that a (t, e)-composite-asymmetric error occurs in$$\mathcal {X}$$ $X$. For general values ofm, n, w, t, ande, we propose new constructions of (t, e)-CAECCs with redundancy at most$$(t-1)\log (m) + O(1)$$ $(t-1)log\left(m\right)+O\left(1\right)$, whereO(1) is independent of the code lengthm. In particular, this yields a class of (2, e)-CAECCs that are optimal in terms of redundancy. Whenmis a prime power, the redundancy can be further reduced to$$(t-1)\log (m) - O(\log (m))$$ $(t-1)log\left(m\right)-O(log(m\left)\right)$. To further increase the code size, we introduce a combinatorial object called a weak$$B_e$$ $B_e$-set. When$$e = w$$ $e=w$, we present an efficient encoding and decoding method for our codes. Finally, we explore potential improvements by relaxing the requirement of unique decoding to list-decoding. We show that when the list size ist! or an exponential function oft, there exist list-decodable (t, e)-CAECCs with constant redundancy. When the list size is two, we construct list-decodable (3, 2)-CAECCs with redundancy$$\log (m) + O(1)$$ $log\left(m\right)+O\left(1\right)$. 

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