DroTrack: High-speed Drone-based Object Tracking Under Uncertainty

We present DroTrack, a high-speed visual single-object tracking framework for drone-captured video sequences. Most of the existing object tracking methods are designed to tackle well-known challenges, such as occlusion and cluttered backgrounds. The complex motion of drones, i.e., multiple degrees of freedom in three-dimensional space, causes high uncertainty. The uncertainty problem leads to inaccurate location predictions and fuzziness in scale estimations. DroTrack solves such issues by discovering the dependency between object representation and motion geometry. We implement an effective object segmentation based on Fuzzy C Means (FCM). We incorporate the spatial information into the membership function to cluster the most discriminative segments. We then enhance the object segmentation by using a pre-trained Convolution Neural Network (CNN) model. DroTrack also leverages the geometrical angular motion to estimate a reliable object scale. We discuss the experimental results and performance evaluation using two datasets of 51,462 drone-captured frames. The combination of the FCM segmentation and the angular scaling increased DroTrack precision by up to $9\%$ and decreased the centre location error by $162$ pixels on average. DroTrack outperforms all the high-speed trackers and achieves comparable results in comparison to deep learning trackers. DroTrack offers high frame rates up to 1000 frame per second (fps) with the best location precision, more than a set of state-of-the-art real-time trackers.Comment: 10 pages, 12 figures, FUZZ-IEEE 202

Multi-Bernoulli filter based sensor selection with limited sensing range for multi-target tracking

In this paper, we consider a sensor network with limited sensing range and present a sensor selection algorithm for multi-target tracking problem. The proposed algorithm is based on the multi-Bernoulli filtering and a collection of sub-selection problems for individual target. A sub-selection problem for each target is investigated under the framework of partially observed Markov decision process. Each sub-selection problem is solved using a combination of information theoretic method and limited sensing range. Numerical studies validate the effectiveness of our method for multi-target tracking scenario in a sensor network

Lumbopelvic Sagittal Alignment and Foraminal Height from Single Interbody Cage in L5-S1 Segment: Comparison between Anterior Cage for OLIF (Oblique Lumbar Interbody Fusion) and Curvilinear Cage for TLIF (Transforaminal Interbody Fusion)

Objective To evaluate a radiological difference between the oblique lumbar interbody fusion (OLIF) L5-S1 and transforaminal lumbar interbody fusion (TLIF) L5-S1 procedure. Methods 16 patients who underwent single-level OLIF L5-S1 and 32 patients of TLIF L5-S1 were retrospectively reviewed. Assessment of the lumbopelvic parameters and the height of disc space and L5-S1 neural foramen was performed before surgery as well as a month after surgery. Results Preoperatively, OLIF L5-S1 group and TLIF group showed similar lumbar lordosis (LL), segmental lordosis (SL), pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS); (p=0.08, 0.48, 0.67, 0.19 and 0.12, respectively). Postoperatively those parameters did not show statistically significant differences between two groups (p=0.17, 0.32, 0.53, 0.16 and 0.19, respectively). In terms of disc and foraminal height, the OLIF L5-S1 group showed significant greater increase of posterior disc height and foraminal height (p=0.01 and 0.00). There was no significant differences between the two groups in mean VAS and ODI score over the follow-up period. Conclusion This study demonstrates that both OLIF L5-S1 group and TLIF L5-S1 group had similar ability of achieving lumbopelvic alignment however, increase of foraminal height was greater in patients with OLIF L5-S1 group

Specific heat and validity of quasiparticle approximation in the half-filled Landau level

We calculate the specific heat of composite fermion system in the half-filled Landau level. Two different methods are used to examine validity of the quasiparticle approximation when the two-body interaction is given by $V(q) = V_0 / q^{2-\eta}$ ($1 \le \eta \le 2$). The singular part of the specific heat is calculated from the free energy of the gauge field, which is compared with the specific heat calculated from the quasiparticle approximation via the singular self-energy correction due to the gauge field fluctuations. It turns out that two results are in general different and they coincide only for the case of the Coulomb interaction ($\eta = 1$). This result supports the fact that the quasiparticle approximation is valid only for the case of the Coulomb interaction. It is emphasized that this result is obtained by looking at a gauge-invariant quantity -- the specific heat.Comment: 8 pages, Revte

Analysis of reports on orphan lung diseases in Korean children

PurposeOrphan lung diseases are defined as lung diseases with a prevalence of 1 or less in 2,000 individuals. Despite an increase in the numbers of patients with such diseases, few studies on Korean children have appeared. To obtain epidemiologic and demographic data on these diseases, we systematically reviewed reports on pediatric orphan lung diseases in Korea over the last 50 years.MethodsWe reviewed 223 articles that have appeared since 1958 on orphan lung diseases in Korean children. These articles described a total of 519 patients aged between 0 and 18 years. We classified patients by year of publication, diagnosis, geographic region, and journal.ResultsOf 519 patients, 401 had congenital cystic lung diseases and 66 had bronchiolitis obliterans. About 80% of patients were described in reports published in three journals, Pediatric Allergy and Respiratory Disease (Korea), the Korean Journal of Pediatrics, and the Korean Journal of Thoracic and Cardiovascular Surgery, in which papers on 157 (30.2%), 138 (26.6%), and 111 (21.4%) patients appeared, respectively. The frequency of publication of case reports has increased since 1990. Of the 519 patients, 401 (77.3%) were from Seoul/Gyeonggi-do and 72 (13.9%) from Busan/Gyeongsangnam-do.ConclusionThe prevalence of pediatric orphan lung disease has increased since 1990, and some provinces of Korea have a higher incidence of these diseases than do others. Studies exploring the incidence of pediatric orphan lung diseases in Korea are needed for effective disease management

Effects of Intronic and Exonic Polymorphisms of Paraoxonase 1 (PON1) Gene on Serum PON1 Activity in a Korean Population

Paraoxonase 1 (PON1) hydrolyzes a number of toxic organophosphorous compounds and reduces lipid peroxide accumulation, and PON1 genetic polymorphisms in the coding region modulate serum PON1 activity. In this study, we investigated the association between 3 polymorphisms of PON1 located in intron 5 (17899insdelTT and 17974CT) and exon 6 (192QR) and serum PON1 activity. The genetic polymorphisms and serum activity of PON1 were analyzed in 153 healthy Koreans by using a direct sequencing assay and spectrophotometric method, respectively. A significant linkage disequilibrium (LD) was observed between all tested single nucleotide polymorphisms, with the strongest LD observed between 17899insdelTT and 192QR (D' = 0.984). The 17899insdelTT, 17974CT and 192QR genetic polymorphisms were associated with significant differences in serum paraoxonase activity. In multiple regression analyses, smoking, triglyceride level, high-density lipoprotein (HDL) level, and the 17899insdelTT and 192QR genetic polymorphisms were significant determinants of serum paraoxonase activity, while age, smoking, triglyceride level, HDL level, and the 192QR genetic polymorphism were significant determinants of serum arylesterase activity. These results suggest that although the 192QR genetic polymorphism in the coding region of PON1 is primarily associated with serum PON1 activity, the intronic polymorphisms are also involved in serum PON1 activity, and this association may be mediated by LD