Guided Wave Analysis of Hollow Optical Fiber for Mode-Coupling Device Applications

In this paper, optical mode characteristics of hollow optical fibers are thoroughly analyzed using finite element method. The guided modes along the ring core and cladding are identified and their optical properties are investigated. For the core modes, we investigated intensity distribution, higher order mode cutoff, propagation constant, and chromatic dispersion. The mode coupling between the fundamental mode and the excited modes in both core modes and cladding modes are discussed for applications in mode-coupling devices.     

Changes in linguistic behaviors based on smart speaker task performance and pragmatic skills in multiple turn-taking interactions

In the current study, we conducted a Wizard-of-Oz experiment using a smart speaker to investigate how smart speakers’ task performance (success vs. failure) and pragmatic levels (high vs. low) alter users’ linguistic behaviors during multiple turn-taking conversations. The linguistic behaviors analyzed in this study included the mean length of utterance, give-up and topic development frequency. Furthermore, we examined what kinds of pragmatic skills smart speakers need to sustain multiple turn-taking interactions. The results suggest that smart speakers’ performance levels and pragmatic skills have different effects on linguistic behaviors. Task performance and the pragmatic levels of smart speaker did not change participants’ utterance lengths. Giving up on conversations when tasks were not successfully completed occurred more frequently with smart speakers with low pragmatic capabilities. Topic development occurred more frequently when people interacted with smart speakers with high pragmatic capabilities or when tasks were accomplished. The notable requisite pragmatic skills for smart speakers included the abilities to specify and describe information, react to indirect behavior, and appreciate humor/ironic humor. The findings of this study may have implications for designing dialogue for artificial conversational agents in various conversational settings.

     

Toward a conversational model for counsel robots: how different question types elicit different linguistic behaviors

Intelligent Service Robotics - In recent years, robots have been playing the role of counselor or conversational partner in everyday dialogues and interactions with humans. For successful...     

High Strength Conductive Composites with Plasmonic Nanoparticles Aligned on Aramid Nanofibers

Rapidly evolving fields of biomedical, energy, and (opto)electronic devices bring forward the need for deformable conductors with constantly rising benchmarks for mechanical properties and electronic conductivity. The search for conductors with improved strength and strain have inspired the multiple studies of nanocomposites and amorphous metals. However, finding conductors that defy the boundaries of classical materials and exhibit simultaneously high strength, toughness, and fast charge transport while enabling their scalable production, remains a difficult materials engineering challenge. Here, composites made from aramid nanofibers (ANFs) and gold nanoparticles (Au NPs) that offer a new toolset for engineering high strength flexible conductors are described. ANFs are derived from Kevlar macrofibers and retain their strong mechanical properties and temperature resilience. Au NPs are infiltrated into a porous, free‐standing aramid matrix, becoming aligned on ANFs, which reduces the charge percolation threshold and facilitates charge transport. Further thermal annealing at 300 °C results in the Au‐ANF composites with an electrical conductivity of 1.25 × 10⁴ S cm^?1 combined with a tensile strength of 96 MPa, a Young's modulus of 5.29 GPa, and a toughness of 1.3 MJ m^?3. These parameters exceed those of most of the composite materials, and are comparable to those of amorphous metals but have no volume limitations. The plasmonic optical frequencies characteristic for constituent NPs are present in the composites with ANFs enabling plasmon‐based optoelectronic applications.