Report: Africa Days 2015 – 2nd Ethio-Czech Conference on Africa (Pilsen, 15.-16.10.2015)

The conference represents an important stepping-stone in the cooperation of the Czech Centre for African Studies based at the University of West Bohemia in Pilsen, where the conference was organized, and the Addis Ababa University in Ethiopia. It was also a continuation of a series of previous meetings and an exhibition (20th century Revisited: Relations between former Czechoslovakia and Ethiopia) that had been on show from October 1st to November 30th at the Ethnographic Museum of Addis Ababa University, Ethiopia. Africa Days 2015 (2nd Ethio-Czech Conference on Africa) was the fourth event of its kind organized or co-organized by the Centre of African Studies in Pilsen since 2013. Last year, the 1st Central European African Studies Conference was hosted in Pilsen, and later that year, the 1st Ethio-Czech Conference on Africa was co-organized by Jimma University (Ethiopia) and the University of West Bohemia in Pilsen (Czech Republic)

Nature-Based Municipal Flood Resilience: Land Conservation Strategies in New Hampshire’s Coastal Watershed

Land conservation is a nature-based approach to managing flood risks from fluvial flooding, coastal storm surge, and sea-level rise. This poster presents the design of ongoing research that aims to understand how New Hampshire’s (NH) coastal watershed municipalities implement land protection and conservation to reduce flood risk, the roles of local communities, land conservation organizations, and regional planning agencies in land conservation for flood risk management, how local decision-makers and stakeholders perceive flooding risks, and what institutional changes are needed to facilitate nature-based flood risk management. Research methods include (1) semi-structured interviews with individuals in New Hampshire representing a broad range of professional roles related to land conservation, including town officials, land trusts, environmental and planning organizations, and state agencies, and (2) analysis of existing studies, plans, and reports on flood risk management in New Hampshire. This poster also presents a framework to categorize how municipalities develop their land conservation priorities. This poster was presented virtually at the UNH Annual Graduate Research Conference on April 20 – 21, 2020

Nature-Based Municipal Flood Resilience and Conservation Priorities in New Hampshire’s Coastal Watershed

Land conservation is a non-structural approach to managing flood hazards through water retention, protecting areas where floodwaters can be stored to prevent downstream flooding, and prevention, protecting floodplains to avoid added risks from new construction and infrastructure. This presentation presents preliminary findings from ongoing research investigating how New Hampshire’s coastal watershed municipalities are implementing land conservation to manage coastal and riverine flood risks. Specifically, we analyze (1) the kinds of criteria municipalities are using to prioritize land conservation and whether managing flood risks is incorporated into the criteria, and (2) the factors that may explain variation observed across municipal land conservation strategies. This research is based on an analysis of publicly available planning documents and 28 semi-structured interviews conducted with municipal staff and officials during 9/2018 – 4/2019 including conservation commission chairs and town planners. Qualitative analysis of the interviews is ongoing. Preliminary analysis suggests there is significant variation across municipalities in the use of criteria for land conservation and that flood risk mitigation is often part of multi-objective selection criteria. Common land conservation criteria include: water resources protection, flood mitigation, climate regulation, nutrient cycling and uptake, soil retention and formation, aesthetic and scenic value, community character, recreation, public access, historic value, and wood supply. Even though nearly all municipalities include land conservation criteria in planning documents, a surprising percent of interviewees (29%) report not using criteria to prioritize land conservation, which suggests a possible disconnect between strategic planning and implementation. Many communities integrate local and regional priorities in developing their land conservation strategies. And, many communities struggle to prioritize flood risk mitigation relative to other competing needs. We conclude with a few examples of data presentation products from this research and ideas for next steps. This presentation was given at the September 10th, 2020 meeting of the Great Bay Resource Protection Partnership. More information about the Great Bay Resource Protection Partnership can be found at: http://www.greatbaypartnership.org

Effects of virtual acoustics on dynamic auditory distance perception

Sound propagation encompasses various acoustic phenomena including reverberation. Current virtual acoustic methods, ranging from parametric filters to physically-accurate solvers, can simulate reverberation with varying degrees of fidelity. We investigate the effects of reverberant sounds generated using different propagation algorithms on acoustic distance perception, i.e., how faraway humans perceive a sound source. In particular, we evaluate two classes of methods for real-time sound propagation in dynamic scenes based on parametric filters and ray tracing. Our study shows that the more accurate method shows less distance compression as compared to the approximate, filter-based method. This suggests that accurate reverberation in VR results in a better reproduction of acoustic distances. We also quantify the levels of distance compression introduced by different propagation methods in a virtual environment.Comment: 8 Pages, 7 figure

Auditory distance perception in humans: a review of cues, development, neuronal bases, and effects of sensory loss.

Auditory distance perception plays a major role in spatial awareness, enabling location of objects and avoidance of obstacles in the environment. However, it remains under-researched relative to studies of the directional aspect of sound localization. This review focuses on the following four aspects of auditory distance perception: cue processing, development, consequences of visual and auditory loss, and neurological bases. The several auditory distance cues vary in their effective ranges in peripersonal and extrapersonal space. The primary cues are sound level, reverberation, and frequency. Nonperceptual factors, including the importance of the auditory event to the listener, also can affect perceived distance. Basic internal representations of auditory distance emerge at approximately 6 months of age in humans. Although visual information plays an important role in calibrating auditory space, sensorimotor contingencies can be used for calibration when vision is unavailable. Blind individuals often manifest supranormal abilities to judge relative distance but show a deficit in absolute distance judgments. Following hearing loss, the use of auditory level as a distance cue remains robust, while the reverberation cue becomes less effective. Previous studies have not found evidence that hearing-aid processing affects perceived auditory distance. Studies investigating the brain areas involved in processing different acoustic distance cues are described. Finally, suggestions are given for further research on auditory distance perception, including broader investigation of how background noise and multiple sound sources affect perceived auditory distance for those with sensory loss.The research was supported by MRC grant G0701870 and the Vision and Eye Research Unit (VERU), Postgraduate Medical Institute at Anglia Ruskin University.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.3758/s13414-015-1015-

Mediating Performance Through Virtual Agents

This paper presents the process of creation of virtual agents used in a virtual reality performance. The performance aimed to investigate how drama and performance could inform the creation of virtual agents and also how virtual reality could raise questions for drama and performance. The virtual agents were based on the performance of 2 actors. This paper describes the process of preparing the actors, capturing their performances and transferring them to the virtual agents. A second set of agents was created using non-professional 'naive performers' rather than actors

An overview of the major phenomena of the localization of sound sources by normal-hearing, hearing-impaired, and aided listeners

Localizing a sound source requires the auditory system to determine its direction and its distance. In general, hearing-impaired listeners do less well in experiments measuring localization performance than normal-hearing listeners, and hearing aids often exacerbate matters. This article summarizes the major experimental effects in direction (and its underlying cues of interaural time differences and interaural level differences) and distance for normal-hearing, hearing-impaired, and aided listeners. Front/back errors and the importance of self-motion are noted. The influence of vision on the localization of real-world sounds is emphasized, such as through the ventriloquist effect or the intriguing link between spatial hearing and visual attention

Auditory spatial representations of the world are compressed in blind humans

Compared to sighted listeners, blind listeners often display enhanced auditory spatial abilities such as localization in azimuth. However, less is known about whether blind humans can accurately judge distance in extrapersonal space using auditory cues alone. Using virtualization techniques, we show that auditory spatial representations of the world beyond the peripersonal space of blind listeners are compressed compared to those for normally sighted controls. Blind participants overestimated the distance to nearby sources, and underestimated the distance to remote sound sources, in both reverberant and anechoic environments, and for speech, music and noise signals. Functions relating judged and actual virtual distance were well fitted by compressive power functions, indicating that the absence of visual information regarding the distance of sound sources may prevent accurate calibration of the distance information provided by auditory signals

Perceptual constancy in auditory perception of distance to railway tracks

Distance to a sound source can be accurately estimated solely from auditory information. With a sound source such as a train that is passing by at a relatively large distance, the most important auditory information for the listener for estimating its distance consists of the intensity of the sound, spectral changes in the sound caused by air absorption, and the motion-induced rate of change of intensity. However, these cues are relative because prior information/experience of the sound source-its source power, its spectrum and the typical speed at which it moves-is required for such distance estimates. This paper describes two listening experiments that allow investigation of further prior contextual information taken into account by listeners-viz., whether they are indoors or outdoors. Asked to estimate the distance to the track of a railway, it is shown that listeners assessing sounds heard inside the dwelling based their distance estimates on the expected train passby sound level outdoors rather than on the passby sound level actually experienced indoors. This form of perceptual constancy may have consequences for the assessment of annoyance caused by railway noise.Full Tex