Can ChatGPT Detect Intent? Evaluating Large Language Models for Spoken Language Understanding

Recently, large pretrained language models have demonstrated strong language understanding capabilities. This is particularly reflected in their zero-shot and in-context learning abilities on downstream tasks through prompting. To assess their impact on spoken language understanding (SLU), we evaluate several such models like ChatGPT and OPT of different sizes on multiple benchmarks. We verify the emergent ability unique to the largest models as they can reach intent classification accuracy close to that of supervised models with zero or few shots on various languages given oracle transcripts. By contrast, the results for smaller models fitting a single GPU fall far behind. We note that the error cases often arise from the annotation scheme of the dataset; responses from ChatGPT are still reasonable. We show, however, that the model is worse at slot filling, and its performance is sensitive to ASR errors, suggesting serious challenges for the application of those textual models on SLU.Comment: 6 pages, 2 figures; Accepted by Interspeech 202

A multiple-hole input coupler for a 372 GHz gyro-travelling wave amplifier

The design of a multiple-hole coupler that operates at a center frequency of 372 GHz for use in a gyrotron travelingwave amplifier (gyro-TWA) is presented. In simulations, the coupler achieved 35% bandwidth from 289GHz to–410 GHz with transmission losses of -0.5 dB predicted

Input coupling systems for millimetre-wave gyrotron travelling wave amplifiers

Input couplers for millimetre-wave gyrotron travelling wave amplifiers are presented in this study. A W-band input coupling system composed of a pillbox window, a smoothly curved waveguide bend, a T-junction and a broadband reflector was numerically optimised, constructed and measured. An average transmission coefficient of −2.0 dB over a designed operating frequency range was measured. Additionally, a higher-frequency input coupler for operation at a central frequency of 372 GHz was also designed based on a multiple-hole coupling configuration. The simulated transmission coefficient was −0.5 dB if the ohmic loss is not considered

Measurement of an upgraded input coupling system for W-band gyro-TWA

A gyrotron traveling-wave amplifier (gyro-TWA) operating at W-band has been upgraded and experimentally measured. In this paper, the design and measurement of the upgraded input coupling system for the gyro-TWA is presented. In the measurement, the transmission coefficient of the coupler is at an optimal level of about -1 dB

Design study of a 372 GHz higher order mode input coupler

The design of a higher order mode  (HOM) input coupler for a low-THz gyrotron travelling wave amplifier (gyro-TWA) is presented. A two-branch waveguide coupler based on the even distribution of incident power is designed to couple the rectangular TE10 mode to the circular TE61 mode. The optimised tapered waveguide input coupler achieved an operating frequency range of 359 – 385 GHz, equating to a bandwidth of 7%. A prototype waveguide coupler scaled to W-band (75GHz to 110GHz) was manufactured. Vector Network Analyser (VNA) measured return loss of the HOM coupler is shown to be < 10dB at 90 – 96 GHz. A transmission and phase measurement is presented to analyse TE61 mode conversion in the coupler

TE10 R-TE11c input coupler for a low-THz gyro-TWA

The design of a fundamental rectangular-to-circular coaxial cavity input coupler for a low-THz gyro-traveling wave amplifier (TWA) is presented. Theoretical and numerical approaches to the design of the coaxial cavity input coupler are introduced. The design is optimized for operation between 360-384 GHz, achieving a transmission bandwidth of 7.5% (358-386 GHz). A comment on the manufacturability of sub-mm waveguide channels is included

Design study of a fundamental mode input coupler for a 372-GHz gyro-TWA I : rectangular-to-circular coupling methods

The design of two fundamental mode rectangular-to-circular waveguide input couplers for a low-terahertz gyrotron-traveling wave amplifier (gyro-TWA) is presented. A T-junction input coupler with a Bragg reflector and a multiple-hole directional coupler were optimized for operation between 360 and 384 GHz, the proposed gyro-TWA bandwidth. The T-junction coupler and the multiple-hole coupler achieved the respective bandwidths of 10% and 35%. The benefits and potential limitations of the low-terahertz wave coupler topologies are discussed alongside the challenging manufacturing methods of the submillimeter-wave components

Design and measurement of a broadband sidewall coupler for a W-band gyro-TWA

The input coupler is an important component for a microwave amplifier. In this paper, a sidewall single-hole input coupler for a W-band gyrotron traveling-wave amplifier that operates at the frequency range of 90–100 GHz was designed and measured. Instead of using a cutoff waveguide, a broadband Braggtype reflector with a small spread in phase was optimized for use as part of the input coupler. The minimum radius of the reflector was two times the size of a cutoff waveguide, which reduced the possibility for some of the beam electrons being collected in this section and lost to the amplifier interaction region

Simulation of rectangular TE10 to circular TE11 terahertz mode converters

Two designs of fundamental mode rectangular to circular waveguide TE10 to TE11 mode converter are presented. The waveguide transitions are optimized for operation as an input coupler on a 372 GHz gyro-TWA for Dynamic Nuclear Polarization (DNP) enhancement of NMR imaging. A T-junction input coupler and a multiple hole directional coupler were optimized for operation between 360-384 GHz. The T-junction coupler and the multiple hole coupler exhibited bandwidths of 10% and 35% respectively with a high coupling factor of > -1 dB

Women’s experience of episiotomy: a qualitative study from China

Objective: To describe women’s experience of episiotomy in urban China. Design: This is a semistructured, indepth interview with women after episiotomy. We analysed transcriptions using thematic analysis in Chinese. Emerging themes were debated in English to finalise interpretation. Setting: Two community health centres and four hospitals in Shanghai, China. Participants: Purposive sampling of 30 postpartum women who had experienced episiotomy; 25 were primiparous and 4 had deliveries by forceps. We interviewed health providers to complement the data. Results: We identified four main themes: (1) women’s views of the procedure vary considerably; (2) pain interferes with daily life for weeks; (3) long-term anxiety is a consequence for some, described as a ‘psychological shadow’; and (4) societal norms assume women will not complain. Conclusion: Women receive little information in advance about episiotomy, yet the procedure has a wide range of physical and psychological consequences. This includes long-term anxiety about the damage done to them as women