2,788 research outputs found
Graph 4-braid groups and Massey products
We first show that the braid group over a graph topologically containing no
-shape subgraph has a presentation related only by commutators. Then
using discrete Morse theory and triple Massey products, we prove that a graph
topologically contains none of four prescribed graphs if and only if its
4-braid groups is a right-angled Artin group.Comment: 23 pages, 4 figure
Effect of a Er, Cr:YSGG laser and a Er:YAG laser treatment on oral biofilm-contaminated titanium
Implant surface decontamination is a challenging procedure for therapy of peri-implant disease. Objective: This study aimed to compare the effectiveness of decontamination on oral biofilm-contaminated titanium surfaces in Er:YAG laser, Er, Cr:YSGG laser, and plastic curette. Methodology: For oral biofilms formation, six participants wore an acrylic splint with eight titanium discs in the maxillary arch for 72 hours. A total of 48 contaminated discs were distributed among four groups: untreated control; decontamination with plastic curettes; Er, Cr:YSGG laser; and Er:YAG laser irradiation. Complete plaque removal was estimated using naked-eye and the time taken was recorded; the residual plaque area was measured and the morphological alteration of the specimen surface was observed by scanning electron microscopy. The total bacterial load and the viability of adherent bacteria were quantified by live or dead cell labeling with fluorescence microscopy. Results: The mean treatment time significantly decreased based on the treatment used in the following order: Er:YAG, Er, Cr:YSGG laser, and plastic curettes (234.9±25.4 sec, 156.1±12.7 sec, and 126.4±18.6 sec, P=0.000). The mean RPA in the Er, Cr:YSGG laser group (7.0±2.5%) was lower than Er:YAG and plastic curettes groups (10.3±2.4%, 12.3±3.6%, p=0.023). The viable bacteria on the titanium surface after Er, Cr:YSGG laser irradiation was significantly lower compared to the decontamination with plastic curette (P=0.05) but it was not significantly different from the Er:YAG laser irradiation. Conclusion: We found that Er:YAG laser and Er, Cr:YSGG laser irradiation were effective methods for decontaminations without surface alterations
Kinematic relationship between rotation of lumbar spine and hip joints during golf swing in professional golfers
AD-YOLO: You Look ONly Once in Training Multiple Sound Event Localization and Detection
Sound event localization and detection (SELD) combines the identification of
sound events with the corresponding directions of arrival (DOA). Recently,
event-oriented track output formats have been adopted to solve this problem;
however, they still have limited generalization toward real-world problems in
an unknown polyphony environment. To address the issue, we proposed an
angular-distance-based multiple SELD (AD-YOLO), which is an adaptation of the
"You Look Only Once" algorithm for SELD. The AD-YOLO format allows the model to
learn sound occurrences location-sensitively by assigning class responsibility
to DOA predictions. Hence, the format enables the model to handle the polyphony
problem, regardless of the number of sound overlaps. We evaluated AD-YOLO on
DCASE 2020-2022 challenge Task 3 datasets using four SELD objective metrics.
The experimental results show that AD-YOLO achieved outstanding performance
overall and also accomplished robustness in class-homogeneous polyphony
environments.Comment: 5 pages, 3 figures, accepted for publication in IEEE ICASSP 202
A Score-Based Evaluation Model for Rehabilitation of Existing Pumped Storage Hydropower Plant Construction
As the proportion of new and renewable energy increases, power control demands are becoming more frequent due to variability in power generation. As a complementary means against this, the pumped storage hydropower plants (PSHP) are attracting attention as energy storage systems (ESS), but it has high construction costs. Therefore, this study aims to improve the economic feasibility by developing the evaluation model of the existing infrastructure into an upper/lower dam suitable for PSHP. The concept of upper dam capacity is newly defined, and the evaluation index is constructed using normalization. A new evaluation system is presented for five factors: environment, stability, energy, capacity, and economy. Finally, it is tested in the pilot area in Korea. Several candidates, including the PSHP in operation, are found to have been distributed with higher scores. These results will help to satisfy the selection of candidates during the preliminary feasibility study phase, and programming them will enable more accurate and rapid assessment
Dispersion of Vascular Plant in An-do, Korea
AbstractThe vascular plants observed in the area were composed of a total of 342 taxa; 104 families, 239 genus, 309 species, 30 varieties, 2 forms and 1 sub-species. The endangered species found in the area were Glehnia littoralis Fr. Schm. and Milletia japonica (Siebold & Zucc.) A.Gray. The five endemic plants were found growing in the area like Carpinus coreana Nakai., Celtis choseniana Nakai, Clematis trichotoma, Spiraea prunifolia for. simpliciflora and Weigela subsessilis L.H.Bailey. Specialized plants of Geumodo were a total of 45 species; 34 taxa in Grade I, 10 taxa in Grade III, and 1 taxon in Grade V. Glehnia littoralis Fr. Schm. and Milletia japonica (Siebold & Zucc.) A.Gray confirmed in this study formed a colony alongside the coast and mountain paths. Currently, the construction to build water supply and sewer systems destroyed part of the colony. Therefore, in the long-term perspective, the conservation plan such as comprehensive research and monitoring on the ecosystem shall be established to protect indeciduous plants in the warm temperate zone
Quantitative Screening of Cervical Cancers for Low-Resource Settings: Pilot Study of Smartphone-Based Endoscopic Visual Inspection After Acetic Acid Using Machine Learning Techniques
Background: Approximately 90% of global cervical cancer (CC) is mostly found in low- and middle-income countries. In most cases, CC can be detected early through routine screening programs, including a cytology-based test. However, it is logistically difficult to offer this program in low-resource settings due to limited resources and infrastructure, and few trained experts. A visual inspection following the application of acetic acid (VIA) has been widely promoted and is routinely recommended as a viable form of CC screening in resource-constrained countries. Digital images of the cervix have been acquired during VIA procedure with better quality assurance and visualization, leading to higher diagnostic accuracy and reduction of the variability of detection rate. However, a colposcope is bulky, expensive, electricity-dependent, and needs routine maintenance, and to confirm the grade of abnormality through its images, a specialist must be present. Recently, smartphone-based imaging systems have made a significant impact on the practice of medicine by offering a cost-effective, rapid, and noninvasive method of evaluation. Furthermore, computer-aided analyses, including image processing-based methods and machine learning techniques, have also shown great potential for a high impact on medicinal evaluations
Transcanal Endoscopic Ear Surgery for Congenital Cholesteatoma
Objectives As endoscopic instrumentation, techniques and knowledges have significantly improved recently, endoscopic ear surgery has become increasingly popular. Transcanal endoscopic ear surgery (TEES) can provide better visualization of hidden areas in the middle ear cavity during congenital cholesteatoma removal. We aimed to describe outcomes for TEES for congenital cholesteatoma in a pediatric population. Methods Twenty-five children (age, 17 months to 9 years) with congenital cholesteatoma confined to the middle ear underwent TEES by an experienced surgeon; 13 children had been classified as Potsic stage I, seven as stage II, and five as stage III. The mean follow-up period was 24 months. Recurrence of congenital cholesteatoma and surgical complication was observed. Results Congenital cholesteatoma can be removed successfully via transcanal endoscopic approach in all patients, and no surgical complications occurred; only one patient with a stage II cholesteatoma showed recurrence during the follow-up visit, and the patient underwent revision surgery. The other patients underwent one-stage operations and showed no cholesteatoma recurrence at their last visits. Two patients underwent second-stage ossicular reconstruction. Conclusion Although the follow-up period and number of patients were limited, pediatric congenital cholesteatoma limited to the middle ear cavity could be safely and effectively removed using TEES
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