A Design of Nonlinear Scaling and Nonlinear Optimal Motion Cueing Algorithm for Pilot's Station

Motion cueing algorithms (MCA) are often applied in the motion simulators. In this paper, a nonlinear optimal MCA, taking into account translational and rotational motions of a simulator within its physical limitation, is designed for the motion platform aiming to minimize human’s perception error in order to provide a high degree of fidelity. Indeed, the movement sensation center of most MCA is placed at the center of the upper platform, which may cause a certain error. Pilot’s station should be paid full attention to in the MCA. Apart from this, the scaling and limiting module plays an important role in optimizing the motion platform workspace and reducing false cues during motion reproduction. It should be used along within the washout filter to decrease the amplitude of the translational and rotational motion signals uniformly across all frequencies through the MCA. A nonlinear scaling method is designed to accurately duplicate motions with high realistic behavior and use the platform more efficiently without violating its physical limitations. The simulation experiment is verified in the longitudinal/pitch direction for motion simulator. The result implies that the proposed method can not only overcome the problem of the workspace limitations in the simulator motion reproduction and improve the realism of movement sensation, but also reduce the false cues to improve dynamic fidelity during the motion simulation process.

Regional Variation in New Zealand English: the Taranaki Sing-Song Accent

<p>Although lay people confidently assert the existence of regional varieties of New Zealand English, linguists have produced very little evidence to support such claims. There are vocabulary items special to, or favoured by, the people of Southland and the West Coast of the South Island; there are traces of non-prevocalic /r/in Southland and Otago; and there are regional differences in the playground language of New Zealand school children. Attempts to identify further differences between regions have generally not been successful. In most cases linguistic evidence has pointed to either social class or ethnic variation, but not to regional variation. Nevertheless, many New Zealanders assert that a Taranaki variety of New Zealand English exists. This study was designed to test the validity of the claim by comparing samples of New Zealand English from Taranaki with samples from Wellington. The Taranaki sample included speakers from New Plymouth (population 50,000) and the South Taranaki dairy farming community. The Wellington sample was drawn from the Greater Wellington region extending from Porirua in the north to suburbs on the southern coast of the city. Interviewees were located by the social network approach, otherwise known as the 'friend of a friend' approach advocated by Lesley Milroy (1980, 1987a). An index of rural orientation was devised to indicate the degree to which a speaker was oriented towards town or country. This proved helpful in distinguishing between genuinely regional differences, and rural versus urban differences. Factors of gender and age were also considered. It has been claimed that Taranaki English has a 'sing-song' quality, suggesting that an investigation of the intonation of Taranaki speakers would be worthwhile. Comparing features of the intonation of a Taranaki sample with a Wellington sample, this thesis attempts to isolate and measure what contributes to the 'sing-song' perception of Taranaki English. 'Singsong' in this context was taken to mean that the speaker had dynamic pitch; in other words their speech was characterised by a lot of movement up and down in pitch. Auditory analysis of speech samples was undertaken, and intonation features were derived from that analysis. Averaging the number of times a speaker changed pitch direction in each intonation group and then in each accent unit provided global measures of changes in pitch direction. Analysis of nuclear accents gave an indication of whether speakers favoured tunes which were characterised by pitch movement. And analysis of the manner in which accents were approached, whether with a boosted step up in pitch, or with a more standard onset, provided a narrower focus on the amount of pitch movement present. Results indicated that, in general, most Taranaki speakers in the sample showed more pitch dynamism than the Wellingtonians; for some features the males showed more pitch dynamism than the females; and, overall, the elderly speakers showed more pitch dynamism than the younger speakers. There were, however, important exceptions to these generalisations. Factors of Location, Gander and Age interacted significantly for all but one of the features examined and there were clear indications that intonational patterns are undergoing change in both regions studied. Explanations for the exceptional cases are explored in the thesis, and sociolinguistic, social network and geolinguistic theories provide possible clues as to the sources of the differences. Evidence of differences in the degree of pitch dynamism present in the intonation of the Taranaki and Wellington speakers supports claims about regional variation in New Zealand English intonation, but it does not in itself prove the existence of a uniquely Taranaki or a uniquely Wellington way of speaking English.</p>

Regional Variation in New Zealand English: the Taranaki Sing-Song Accent

<p>Although lay people confidently assert the existence of regional varieties of New Zealand English, linguists have produced very little evidence to support such claims. There are vocabulary items special to, or favoured by, the people of Southland and the West Coast of the South Island; there are traces of non-prevocalic /r/in Southland and Otago; and there are regional differences in the playground language of New Zealand school children. Attempts to identify further differences between regions have generally not been successful. In most cases linguistic evidence has pointed to either social class or ethnic variation, but not to regional variation. Nevertheless, many New Zealanders assert that a Taranaki variety of New Zealand English exists. This study was designed to test the validity of the claim by comparing samples of New Zealand English from Taranaki with samples from Wellington. The Taranaki sample included speakers from New Plymouth (population 50,000) and the South Taranaki dairy farming community. The Wellington sample was drawn from the Greater Wellington region extending from Porirua in the north to suburbs on the southern coast of the city. Interviewees were located by the social network approach, otherwise known as the 'friend of a friend' approach advocated by Lesley Milroy (1980, 1987a). An index of rural orientation was devised to indicate the degree to which a speaker was oriented towards town or country. This proved helpful in distinguishing between genuinely regional differences, and rural versus urban differences. Factors of gender and age were also considered. It has been claimed that Taranaki English has a 'sing-song' quality, suggesting that an investigation of the intonation of Taranaki speakers would be worthwhile. Comparing features of the intonation of a Taranaki sample with a Wellington sample, this thesis attempts to isolate and measure what contributes to the 'sing-song' perception of Taranaki English. 'Singsong' in this context was taken to mean that the speaker had dynamic pitch; in other words their speech was characterised by a lot of movement up and down in pitch. Auditory analysis of speech samples was undertaken, and intonation features were derived from that analysis. Averaging the number of times a speaker changed pitch direction in each intonation group and then in each accent unit provided global measures of changes in pitch direction. Analysis of nuclear accents gave an indication of whether speakers favoured tunes which were characterised by pitch movement. And analysis of the manner in which accents were approached, whether with a boosted step up in pitch, or with a more standard onset, provided a narrower focus on the amount of pitch movement present. Results indicated that, in general, most Taranaki speakers in the sample showed more pitch dynamism than the Wellingtonians; for some features the males showed more pitch dynamism than the females; and, overall, the elderly speakers showed more pitch dynamism than the younger speakers. There were, however, important exceptions to these generalisations. Factors of Location, Gander and Age interacted significantly for all but one of the features examined and there were clear indications that intonational patterns are undergoing change in both regions studied. Explanations for the exceptional cases are explored in the thesis, and sociolinguistic, social network and geolinguistic theories provide possible clues as to the sources of the differences. Evidence of differences in the degree of pitch dynamism present in the intonation of the Taranaki and Wellington speakers supports claims about regional variation in New Zealand English intonation, but it does not in itself prove the existence of a uniquely Taranaki or a uniquely Wellington way of speaking English.</p>

Experimental analysis of radially resolved dynamic inflow effects due to pitch steps

The dynamic inflow effect denotes the unsteady aerodynamic response to fast changes in rotor loading due to a gradual adaption of the wake. This does lead to load overshoots. The objective of the paper was to increase the understanding of that effect based on pitch step experiments on a 1.8 m diameter model wind turbine, which are performed in the large open jet wind tunnel of ForWind – University of Oldenburg. The flow in the rotor plane is measured with a 2D laser Doppler anemometer, and the dynamic wake induction factor transients in axial and tangential direction are extracted. Further, integral load measurements with strain gauges and hot-wire measurements in the near and close far wake are performed. The results show a clear gradual decay of the axial induction factors after a pitch step, giving the first direct experimental evidence of dynamic inflow due to pitch steps. Two engineering models are fitted to the induction factor transients to further investigate the relevant time constants of the dynamic inflow process. The radial dependency of the axial induction time constants as well as the dependency on the pitch direction is discussed. It is confirmed that the nature of the dynamic inflow decay is better described by two rather than only one time constant. The dynamic changes in wake radius are connected to the radial dependency of the axial induction transients. In conclusion, the comparative discussion of inductions, wake deployment and loads facilitate an improved physical understanding of the dynamic inflow process for wind turbines. Furthermore, these measurements provide a new detailed validation case for dynamic inflow models and other types of simulations.

A 2D model for the study of equilibrium glide paths of UiS Subsea Freight-Glider

A planar mathematical model for the analysis of equilibrium glide paths of the UiS subsea freight-glider (USFG) is presented. The model is developed using Simscape Multibody in MATLAB/Simulink to study the ever-changing dynamics of the glider. Motion along the heave and pitch direction is regulated by two separate PID controllers. Controllers are tuned for the optimal bandwidth and phase margin to provide the system with ideal gains which satisfy the system requirements. A wide-ranging sensitivity investigation is carried out on the USFG by changing the two key variables, pump flow rate and ballast fraction. The results reflect the advantages of using higher flow capacity and ballast fraction, which should be preferred according to the application, provided if there are no space and weight restrictions. Finally, different glide paths were simulated to observe that, controller gains obtained from the linear model can be improved to acquire better performance in terms of robustness and stability of the system.

Perception and Production of Statement-Question Intonation in Autism Spectrum Disorder: A Developmental Investigation

Prosody or “melody in speech” in autism spectrum disorder (ASD) is often perceived as atypical. This study examined perception and production of statements and questions in 84 children, adolescents and adults with and without ASD, as well as participants’ pitch direction discrimination thresholds. The results suggested that the abilities to discriminate (in both speech and music conditions), identify, and imitate statement-question intonation were intact in individuals with ASD across age cohorts. Sensitivity to pitch direction predicted performance on intonation processing in both groups, who also exhibited similar developmental changes. These findings provide evidence for shared mechanisms in pitch processing between speech and music, as well as associations between low- and high-level pitch processing and between perception and production of pitch.

Experimental analysis of radially resolved dynamic inflow effects due to pitch steps

The dynamic inflow effect denotes the unsteady aerodynamic response to fast changes in rotor loading due to a gradual adaption of the wake. This does lead to load overshoots. The objective of the paper was to increase the understanding of that effect based on pitch step experiments on a 1.8 m diameter model wind turbine, which we performed in the large open jet wind tunnel of ForWind – University of Oldenburg. We measured the flow in the rotor plane with a 2D Laser Doppler Anemometer and were able to extract the dynamic wake induction factor transients in axial and tangential direction. Further, integral load measurements with strain gauges and hot wire measurements in the near and close far wake were performed. Our results show a clear gradual decay of the axial induction factors after a pitch step, giving the first direct experimental evidence of dynamic inflow due to pitch steps. We fitted two engineering models to the induction factor transients to further investigate the relevant time constants of the dynamic inflow process.We discussed the radial dependency of the axial induction time constants as well as the dependency on the pitch direction. We confirmed that the nature of the dynamic inflow decay is better described by two rather than only one time constant. The dynamic changes in wake radius were connected to the radial dependency of the axial induction transients. In conclusion, the comparative discussion of inductions, wake deployment and loads facilitated the improved physical understanding of the dynamic inflow process for wind turbines. Furthermore, these measurements provide a new detailed validation case for dynamic inflow models and other types of simulations.

Music Perception and Speech-in-Noise Skills of Typical Hearing and Cochlear Implant Listeners

Purpose Adult cochlear implant (CI) users rate music as one of the most important auditory stimuli, second to speech perception. However, few studies simultaneously examine music perception and speech-in-noise perception in adult CI recipients. This study explores the effect of auditory status on music perception and speech-in-noise perception recognition in noise as well as the relationship among music engagement, music perception, and speech-in-noise perception. Method Participants include 10 adults with typical hearing (TH) and 10 adults with long-term CI use. All participants completed the Music-Related Quality of Life Questionnaire, which assesses subjective music experiences and their importance; the Pitch Direction Discrimination, Familiar Melody Recognition, and Timbre Recognition subtests of the Clinical Assessment of Music Perception for Cochlear Implants; the Unfamiliar Melody Recognition subtest of the Profile of Music Perception Skills; and the Bamford–Kowal–Bench Speech-in-Noise Test . Results The TH group significantly outperformed the CI group for speech-in-noise perception and on all four music perception tasks. The CI group exhibited not only significantly poorer mean scores but also greater variability in performance compared to the TH group. Only Familiar Melody Recognition and Unfamiliar Melody Recognition subtests significantly correlated with speech-in-noise scores. Conclusions Patients and professionals should not assume speech perception and music perception in adult CI users derive from the same auditory or cognitive foundations. The lack of significant relationships among music engagement, music perception, and speech-in-noise perception scores in adult CI users suggests this population enjoys music despite poor and variable performance in discrete music tasks.

Word Prosody in Second Language Acquisition

The production and perception of a second language (L2) will be affected by any differences between native language (L1) and L2 lexical stress and lexical tone. This chapter first discusses L1 effects on the perception of L2 words that differ in stress, comparing the explanatory power of phonological (stress-parameter-based) and phonetic (cue-based) approaches for L2 learners’ performance in word recognition. Equally, it discusses L1 effects on the production of stress in L2 words, from both a phonological and a phonetic perspective. The discussion then moves on to the L2 acquisition of lexical tone, focusing on differences in the way native speakers and L2 learners make use of lower-level acoustic-phonetic and higher-level linguistic information, their weighting of tonal cues (pitch height and pitch direction), and the role of contextual phonetic and prosodic information. Special attention is paid to major typological differences between L1 and L2 (non-tonal vs. tonal; level tones vs. contour tones). Finally, the efficacy of short-term auditory training in the acquisition of new tonal categories is evaluated. Throughout, the chapter addresses the influence of factors such as age of acquisition and proficiency.

Tone–Melody Matching in tone-Language Singing

Singing in tone languages has been the subject of a good deal of research, which shows that text-setting constraints are the heart of the solution to respecting both the linguistic and the musical functions of pitch. The most important principle in maintaining intelligibility of song texts seems to be the avoidance of contrary settings: musical pitch movement up or down from one syllable to the next should not be the opposite of the linguistically specified pitch direction. This chapter reviews the variations on this theme that have been described in the recent literature, including differences between languages and musical genres. It briefly considers how tonal text-setting might be incorporated into a general theory that includes traditional European metrics.