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This paper examines switch reference (SR) in A’ingae, an understudied isolate language from Amazonian Ecuador. We present a theoretically informed survey of SR, identifying three distinct uses of switch reference: in clause chaining, adverbial clauses, and so-called ‘bridging’ clause linkage. We describe the syntactic and semantic properties of each use in detail, the first such description for A’ingae, showing that the three constructions differ in important ways. While leaving a full syntactic analysis to future work, we argue that these disparate properties preclude a syntactic account that unifies these three constructions to the exclusion of other environments without SR. Conversely, while a full semantic account is also left to future work, we suggest that a unified semantic account in terms of discourse coherence principles appears more promising. In particular, we propose that switch reference in A’ingae occurs in all and only the constructions that are semantically restricted to non-structuring coordinating coherence relations in the sense of Segmented Discourse Representation Theory. 

Debris flow, landslides and material run-outs have significant environmental and economic consequences for numerous industries. High-quality experimental data with controlled boundary conditions can help validate and calibrate the predictive capabilities of mechanistic and semi-empirical numerical models. A novel centrifuge container to model dewatering and run-outs induced by a rapid loss of confinement is presented. The design features a pair of vertical doors opened in-flight to simulate failure of the containing structure. Illustrative centrifuge results investigating the run-out characteristics of a fully saturated, densely deposited class-F fly ash are presented. Modified soil moisture probes to monitor the distributions and time-varying fly-ash water content throughout the testing are explored. Furthermore, the successful use of depth-sensing cameras to reconstruct progressive deformations of the material front at various time scales is demonstrated. Combined water content, pore pressure and deformation measurements provide insight into the material behaviour during the run-out, revealing two time scales at which the deformations occur. However, discrepancies between water contents inferred from the dielectric measurements and electrical conductivities highlight the need for independent verification of the bulk material water content when using the modified probes. Overall, the potential of these innovative instrumentation techniques to complement traditional geotechnical instrumentation is shown. 

SUMMARY The eruption of the submarine Hunga Tonga-Hunga Haʻapai (Hunga Tonga) volcano on 15 January 2022, was one of the largest volcanic explosions recorded by modern geophysical instrumentation. The eruption was notable for the broad range of atmospheric wave phenomena it generated and for their unusual coupling with the oceans and solid Earth. The event was recorded worldwide across the Global Seismographic Network (GSN) by seismometers, microbarographs and infrasound sensors. The broad-band instrumentation in the GSN allows us to make high fidelity observations of spheroidal solid Earth normal modes from this event at frequencies near 3.7 and 4.4 mHz. Similar normal mode excitations were reported following the 1991 Pinatubo (Volcanic Explosivity Index of 6) eruption and were predicted, by theory, to arise from the excitation of mesosphere-scale acoustic modes of the atmosphere coupling with the solid Earth. Here, we compare observations for the Hunga Tonga and Pinatubo eruptions and find that both strongly excited the solid Earth normal mode 0S29 (3.72 mHz). However, the mean modal amplitude was roughly 11 times larger for the 2022 Hunga Tonga eruption. Estimates of attenuation (Q) for 0S29 across the GSN from temporal modal decay give Q = 332 ± 101, which is higher than estimates of Q for this mode using earthquake data (Q = 186.9 ± 5). Two microbarographs located at regional distances (<1000 km) to the volcano provide direct observations of the fundamental acoustic mode of the atmosphere. These pressure oscillations, first observed approximately 40 min after the onset of the eruption, are in phase with the seismic Rayleigh wave excitation and are recorded only by microbarographs in proximity (<1500 km) to the eruption. We infer that excitation of fundamental atmospheric modes occurs within a limited area close to the site of the eruption, where they excite select solid Earth fundamental spheroidal modes of similar frequencies that are globally recorded and have a higher apparent Q due to the extended duration of atmospheric oscillations. 

In the wake of widespread and ongoing travel restrictions that began in early 2020 due to the COVID-19 pandemic, many documentary linguists worldwide shifted to remote work methods in order to continue or, in some cases, begin new projects. This pandemic situation has prompted questions about both methodological and ethical considerations in doing remote fieldwork. In this paper, we discuss the pros and cons of working remotely and discuss ways of working remotely based on our experiences working on projects in West Africa, northwest Amazonia, and Indonesia. We argue that elements of remote fieldwork should become a permanent part of linguistic fieldwork, but that such methods need to be considered in the context of decolonizing language documentation and centering the community’s needs and interests. 

The employment settings for autistic individuals in the USA is grim. As more children are diagnosed with ASD, the number of adolescent and young adult with ASD will increase as well over the next decade. Based on reports, one of the main challenges in securing and retaining employment for individual with ASD is difficulty in communicating and working with others in workplace settings. Most vocational trainings focused on technical skills development and very few addresses teamwork skills development. In this study, we present the design of a collaborative virtual environment (CVE) that support autistic individual to develop their teamwork skills by working together with a partner in a shared virtual space. This paper described the CVE architecture, teamwork-based tasks design and quantitative measures to evaluate teamwork skills. A system validation was also carried out to validate the system design. The results showed that our CVE was able to support multiple users in the same shared environment, the tasks were tolerable by users, and all the quantitative measures are recorded accordingly. 

Increased interest in renewable energy production has created demand for novel methods of electricity production. With a high potential for low cost power generation in locations otherwise isolated from the grid, in-stream hydrokinetic turbines could serve to help meet this growing demand. Hydrokinetic turbines possess higher operations and maintenance (O&M) costs due to their isolated nature and harsh operating environment when compared with other sources of renewable energy. As such, techniques must be developed to mitigate these costs through the application of fault-tolerant control (FTC) and machine condition monitoring (MCM) for increased reliability and maintenance forecasting. Hence, the primary objective of this paper is to address a key limitation in hydrokinetic turbine research: the lack of widely available data for use in developing models by which to conduct FTC and MCM. To this end, a 20 kW research hydrokinetic turbine implemented in Fatigue Aerodynamics Structures and Turbulence (FAST) is presented and housed within the Matlab/Simulink environment. This paper details the high-fidelity simulation platform development together with the characteristics of generated data with a focus on future FTC and MCM implementation. 

Increased interest in renewable energy production has created demand for novel methods of electricity production. With a high potential for low cost power generation in locations otherwise isolated from the grid, in-stream hydrokinetic turbines could serve to help meet this growing demand. Hydrokinetic turbines possess higher operations and maintenance (O&M) costs due to their isolated nature and harsh operating environment when compared with other sources of renewable energy. As such, techniques must be developed to mitigate these costs through the application of fault-tolerant control (FTC) and machine condition monitoring (MCM) for increased reliability and maintenance forecasting. Hence, the primary objective of this paper is to address a key limitation in hydrokinetic turbine research: the lack of widely available data for use in developing models by which to conduct FTC and MCM. To this end, a 20 kW research hydrokinetic turbine implemented in Fatigue Aerodynamics Structures and Turbulence (FAST) is presented and housed within the Matlab/Simulink environment. This paper details the high-fidelity simulation platform development together with the characteristics of generated data with a focus on future FTC and MCM implementation.