40 research outputs found
Three speech sounds, one motor action: Evidence for speech-motor disparity from English flap production
The assumption that units of speech production bear a one-to-one relationship to speech motor actions pervades otherwise widely varying theories of speech motor behavior. This speech produc- tion and simulation study demonstrates that commonly occurring flap sequences may violate this assumption. In the word “Saturday,” a sequence of three sounds may be produced using a single, cyclic motor action. Under this view, the initial upward tongue tip motion, starting with the first vowel and moving to contact the hard palate on the way to a retroflex position, is under active muscular control, while the downward movement of the tongue tip, including the second contact with the hard palate, results from gravity and elasticity during tongue muscle relaxation. This sequence is reproduced using a three-dimensional computer simulation of human vocal tract biomechanics and differs greatly from other observed sequences for the same word, which employ multiple targeted speech motor actions. This outcome suggests that a goal of a speaker is to produce an entire sequence in a biomechanically efficient way at the expense of maintaining parity within the individual parts of the sequence
Utilizing deep learning to predict the number of panicles in wheat (triticum aestivum)
Non-Peer Reviewe
How can drones be used for crop diagnostics?
Non-Peer Reviewe
Global Wheat Head Detection (GWHD) dataset: a large and diverse dataset of high resolution RGB labelled images to develop and benchmark wheat head detection methods
Detection of wheat heads is an important task allowing to estimate pertinent
traits including head population density and head characteristics such as
sanitary state, size, maturity stage and the presence of awns. Several studies
developed methods for wheat head detection from high-resolution RGB imagery.
They are based on computer vision and machine learning and are generally
calibrated and validated on limited datasets. However, variability in
observational conditions, genotypic differences, development stages, head
orientation represents a challenge in computer vision. Further, possible
blurring due to motion or wind and overlap between heads for dense populations
make this task even more complex. Through a joint international collaborative
effort, we have built a large, diverse and well-labelled dataset, the Global
Wheat Head detection (GWHD) dataset. It contains 4,700 high-resolution RGB
images and 190,000 labelled wheat heads collected from several countries around
the world at different growth stages with a wide range of genotypes. Guidelines
for image acquisition, associating minimum metadata to respect FAIR principles
and consistent head labelling methods are proposed when developing new head
detection datasets. The GWHD is publicly available at
http://www.global-wheat.com/ and aimed at developing and benchmarking methods
for wheat head detection.Comment: 16 pages, 7 figures, Dataset pape
Analysis of Locally Coupled 3D Manipulation Mappings Based on Mobile Device Motion
We examine a class of techniques for 3D object manipulation on mobile devices, in which the device's physical motion is applied to 3D objects displayed on the device itself. This "local coupling" between input and display creates specific challenges compared to manipulation techniques designed for monitor-based or immersive virtual environments. Our work focuses specifically on the mapping between device motion and object motion. We review existing manipulation techniques and introduce a formal description of the main mappings under a common notation. Based on this notation, we analyze these mappings and their properties in order to answer crucial usability questions. We first investigate how the 3D objects should move on the screen, since the screen also moves with the mobile device during manipulation. We then investigate the effects of a limited range of manipulation and present a number of solutions to overcome this constraint. This work provides a theoretical framework to better understand the properties of locally-coupled 3D manipulation mappings based on mobile device motion
Biomechanical modeling of English /r/ variants
This study reports an investigation of the well-known context-dependent variation in English /r/ using a biomechanical tongue-jaw-hyoid model. The simulation results show that preferred /r/ variants require less volume displacement, relative strain, and relative muscle stress than variants that are not preferred. This study also uncovers a previously unknown mechanism in tongue biomechanics for /r/ production: Torque in the sagittal plane about the mental spine. This torque enables raising of the tongue anterior for retroflexed [ɻ] by activation of hyoglossus and relaxation of anterior genioglossus. The results provide a deeper understanding of the articulatory factors that govern contextual phonetic variation