DSpace 集合:

Fin Stabilizer-Based Finite-Time H_{??/sub> Interval Type-2 Fuzzy Synthesis for Ship Rolling Motion With Bouc-Wen Hysteresis Under Imperfect Premise Matching}

Thu, 01 Jan 2026 00:00:00 GMT

標題: Fin Stabilizer-Based Finite-Time H_{??/sub> Interval Type-2 Fuzzy Synthesis for Ship Rolling Motion With Bouc-Wen Hysteresis Under Imperfect Premise Matching
作者: Arumugam, Arunkumar; Chang, Wen-Jer; Lee, Yi-Chen; Lin, Yann-Horng; Li, Li; Aslam, Muhammad Shamrooz
摘要: When a ship operates at sea, it undergoes noticeable motions caused by waves and winds, with rolling being the most pronounced. Nowadays, fin stabilizers remain the most widely adopted devices for roll stabilization. However, they often exhibit hysteresis due to variations in hydrodynamic forces. To better address the control problem of ship rolling motion under nonlinearities, uncertainties, and hysteresis, this article proposes an Interval Type-2 (IT2) fuzzy controller design method that incorporates a novel Bouc-Wen (B-W) hysteresis estimator within the Takagi-Sugeno fuzzy model (TSFM) framework. The main contribution of this research lies in developing a B-W hysteresis state estimator within the IT2 TSFM framework to accurately capture the nonlinear hysteresis behavior. An IT2 fuzzy controller corresponding to the IT2 TSFM is developed using the imperfect premise matching method to improve the flexibility of controller design in practical applications. By combining with finite-time control theory, the IT2 fuzzy controller guarantees finite-time boundedness (FTB) and achieves performance index under the finite-time H-infinity criterion. According to Lyapunov theory, a new set of sufficient conditions is formulated using LMIs to guarantee the FTB for the ship rolling system. Finally, the simulation results of the nonlinear ship rolling system using the fin stabilizers are presented to verify the performance of the proposed IT2 fuzzy control approach.}

Use of AI-mediated image analysis to investigate the influence of environmental factors and recreational scuba diving on fish activity patterns in a marine protected area

Thu, 01 Jan 2026 00:00:00 GMT

標題: Use of AI-mediated image analysis to investigate the influence of environmental factors and recreational scuba diving on fish activity patterns in a marine protected area 作者: Chang, Ching-Han; Li, Dong-Lin; Chen, Li-Shu; Shao, Yi-Ta 摘要: Due to inherent constraints on dive duration and inevitable observer effects, traditional underwater visual censuses (UVC) using scuba are of limited use for long-term behavioral monitoring of fish communities and the accurate assessment of any anthropogenic impact on them. Instead, we used an unmanned underwater camera system and YOLOv5 AI technology to assess temporal changes in fish activity patterns relative to diurnal cycles and water temperature changes in a Marine Protected Area (MPA) off the coast of Chaojing Park, Keelung, Taiwan. We confirmed a clear diurnal pattern in fish activity and identified temperature as a possible driver of species-specific activity patterns and behavioral cycles. This is a popular site for recreational diving, and the presence of scuba divers was associated with a significant but temporary avoidance response in fishes, which subsided quickly after the divers had departed. Hour-by-hour data nonetheless indicated that the number of fish present at the site may be influenced by the number of visitors at any given time. An increase in visitors was found to suppress the activity of damselfishes (Pomacentridae) for a short time, but visitor frequency did not significantly alter their daily mean abundance or overall diel activity patterns. While the rapid recovery observed within minutes after diver departure is convincing, the dataset does not allow robust inferences regarding longterm or cumulative effects. Although recreational diving currently appears to induce only transient behavioral shifts in this site's fish, the potential for lasting ecological impact, particularly if visitor density increases beyond current levels, remains uncertain.

Genomic Insights into the Metabolic Traits and Adaptation Mechanisms of Mesophilic Campylobacteria Represented by a Novel Sulfurospirillum Species from Shallow-Water Hydrothermal Vent

Thu, 01 Jan 2026 00:00:00 GMT

標題: Genomic Insights into the Metabolic Traits and Adaptation Mechanisms of Mesophilic Campylobacteria Represented by a Novel Sulfurospirillum Species from Shallow-Water Hydrothermal Vent 作者: Du, Xi; Sun, Mingye; Cheng, Shan; Hwang, Jiang-Shiou; Liu, Rulong; Fang, Jiasong; Wang, Li 摘要: Members of the class Campylobacteria are microaerophilic bacteria widely distributed across diverse environments and are abundant in hydrothermal systems. However, cultivated representatives, particularly from shallow-water vents, remain limited. Here, we investigated the genomic diversity and environmental adaptation of the genus Sulfurospirillum. Phylogenomic analysis revealed a clear separation between terrestrial and marine clades, with relatively few cultured representatives in the marine lineage. Strain 1307, isolated from shallow-water hydrothermal vents, expands the genomic representation of this underexplored clade. Pan-genome analyses based on complete genomes revealed an open pan-genome, indicating ongoing diversification of genus Sulfurospirillum. Further comparison between hydrothermal vent (HTV) and non-HTV lineages identified distinct adaptive features. Vent-associated strains are enriched in genes involved in sulfur metabolism, carbon fixation, the glycine cleavage system (GCS), and the biosynthesis of key cofactors (spermidine, thiamine, lipoate, and heme), reflecting metabolic adaptation to hydrothermal environments. Beyond well-established processes such as sulfur metabolism and autotrophic carbon fixation, the widespread presence of the GCS in vent-associated lineages suggests its potential role as an auxiliary carbon fixation pathway under anaerobic conditions. Overall, this study expands the phylogenetic and genomic diversity of Sulfurospirillum and offers new insights into the mechanisms underlying environmental adaptation and niche differentiation in vent-associated Campylobacteria.

Enhancing electrically driven excitonic emission stability in WSe₂ monolayer through contact engineering with HfN electrode

Thu, 01 Jan 2026 00:00:00 GMT

標題: Enhancing electrically driven excitonic emission stability in WSe₂ monolayer through contact engineering with HfN electrode 作者: Chen, Zheng-Zhe; Peng, Tzu-Yu; Chang, Chiao-Yun; Tsai, Po-Cheng; Wang, Yen-Yu; Tsai, Ya-Ting; Shiu, Hung Wei; Lin, Shih-Yen; Lu, Yu-Jung; Shih, Min-Hsiung 摘要: Two-dimensional (2D) monolayered (ML) transition-metal dichalcogenides (TMDCs) show strong potential for compact optoelectronic devices, such as light-emitting devices (LEDs). Among all, ML WSe2 can potentially offer the highest external quantum efficiency (EQE) under ambient conditions. However, ML TMDC LEDs with conventional noble metal electrodes face challenges like heat accumulation and intensity quenching. We addressed these limitations by incorporating semi-metal HfN electrodes into AC-driven ML WSe2 LEDs. Replacing standard silver electrodes with HfN nearly doubled the EL intensity and reduced the quenching rate by 83%. After 2 & times;109 times of AC pulses injected, HfN could still help maintain over 80% of intensity magnitude, while Ag-electrode LEDs were almost burned out. Furthermore, HfN-electrode LEDs demonstrated superior excitonic EL stability and distinct defect-state recombination suppression after high-temperature treatment. These results highlight HfN electrodes' potential for durable TMDC LEDs and broader applications in 2D photodetectors, modulators, and integrated optoelectronic systems in the future.

DSpace 集合:

Fin Stabilizer-Based Finite-Time H??/sub> Interval Type-2 Fuzzy Synthesis for Ship Rolling Motion With Bouc-Wen Hysteresis Under Imperfect Premise Matching

Use of AI-mediated image analysis to investigate the influence of environmental factors and recreational scuba diving on fish activity patterns in a marine protected area

Genomic Insights into the Metabolic Traits and Adaptation Mechanisms of Mesophilic Campylobacteria Represented by a Novel Sulfurospirillum Species from Shallow-Water Hydrothermal Vent

Enhancing electrically driven excitonic emission stability in WSe2 monolayer through contact engineering with HfN electrode

Fin Stabilizer-Based Finite-Time H_{??/sub> Interval Type-2 Fuzzy Synthesis for Ship Rolling Motion With Bouc-Wen Hysteresis Under Imperfect Premise Matching}

Enhancing electrically driven excitonic emission stability in WSe₂ monolayer through contact engineering with HfN electrode