Science.gov

Sample records for adaptive collective pitch

  1. Adaptive pitch control for variable speed wind turbines

    DOEpatents

    Johnson, Kathryn E [Boulder, CO; Fingersh, Lee Jay [Westminster, CO

    2012-05-08

    An adaptive method for adjusting blade pitch angle, and controllers implementing such a method, for achieving higher power coefficients. Average power coefficients are determined for first and second periods of operation for the wind turbine. When the average power coefficient for the second time period is larger than for the first, a pitch increment, which may be generated based on the power coefficients, is added (or the sign is retained) to the nominal pitch angle value for the wind turbine. When the average power coefficient for the second time period is less than for the first, the pitch increment is subtracted (or the sign is changed). A control signal is generated based on the adapted pitch angle value and sent to blade pitch actuators that act to change the pitch angle of the wind turbine to the new or modified pitch angle setting, and this process is iteratively performed.

  2. Pitching Speed and Glenohumeral Adaptation in High School Pitchers.

    PubMed

    Keller, Robert A; Marshall, Nathan E; Mehran, Nima; Moutzouros, Vasilios

    2015-08-01

    Glenohumeral internal rotational deficit and increased glenohumeral external rotation are common findings in baseball pitchers. To the authors' knowledge, no study has focused on the adaptation of glenohumeral internal rotational deficit and increased glenohumeral external rotation in relation to pitching speed. This study evaluated changes in range of motion in the throwing shoulder in high school pitchers to determine whether changes in internal and external rotation directly correlate with pitch velocity. The shoulders of 22 high school varsity pitchers were evaluated. Standard goniometric technique was used to measure passive external and internal glenohumeral range of motion in both arms. Measurements were evaluated for statistically significant differences in range of motion. Demographic features, including height, weight, and age, were assessed. Fifteen consecutive in-game pitch speeds were recorded, and the fastest pitch was used for evaluation. Pitch speeds were correlated to the player's glenohumeral internal rotational deficit, increased glenohumeral external rotation, and physical demographics. Average age was 16.9 years. Average external rotation of the throwing arm was significantly greater than that of the nonthrowing arm (143.00° vs 130.32°, P=.005). Average internal rotation of the throwing arm was significantly less than that of the nonthrowing arm (49.50° vs 65.90°, P=.006). Both shoulders had similar total arc of motion (throwing shoulder, 192.54; nonthrowing shoulder, 196.23; P=.822). Average maximum velocity was 77.7 mph (maximum, 88 mph; minimum, 66 mph). Maximum pitch velocity did not correlate with changes in glenohumeral internal rotational deficit (P=.683) or increased glenohumeral external rotation (P=.241). There was also no evidence of correlation between pitch velocity and player age, height, weight, or dominant hand. The stress of pitching creates adaptations to the throwing shoulder, even in young athletes. There appears to be

  3. Pitch Adaptation Patterns in Bimodal Cochlear Implant Users: Over Time and After Experience

    PubMed Central

    Reiss, Lina A.J.; Ito, Rindy A.; Eggleston, Jessica L.; Liao, Selena; Becker, Jillian J.; Lakin, Carrie E.; Warren, Frank M.; McMenomey, Sean O.

    2014-01-01

    Background Pitch plasticity has been observed in Hybrid cochlear implant (CI) users. Does pitch plasticity also occur in bimodal CI users with traditional long-electrode CIs, and is pitch adaptation pattern associated with electrode discrimination or speech recognition performance? Objective Characterize pitch adaptation patterns in long-electrode CI users, correlate these patterns with electrode discrimination and speech perception outcomes, and analyze which subject factors are associated with the different patterns. Methods Electric-to-acoustic pitch matches were obtained in 19 subjects over time from CI activation to at least 12 months after activation, and in a separate group of 18 subjects in a single visit after at least 24 months of CI experience. Audiometric thresholds, electrode discrimination performance, and speech perception scores were also measured. Results Subjects measured over time had pitch adaptation patterns that fit one of the following categories: 1) “Pitch-adapting”, i.e. the mismatch between perceived electrode pitch and the corresponding frequency-to-electrode allocations decreased; 2) “Pitch-dropping”, i.e. the pitches of multiple electrodes dropped and converged to a similar low pitch; 3) “Pitch-unchanging”, i.e. electrode pitches did not change. Subjects measured after CI experience had a parallel set of adaptation patterns: 1) “Matched-pitch”, i.e. the electrode pitch was matched to the frequency allocation; 2) “Low-pitch”, i.e. the pitches of multiple electrodes were all around the lowest frequency allocation; 3) “Nonmatched-pitch”, i.e. the pitch patterns were compressed relative to the frequency allocations and did not fit either the matched-pitch or low-pitch categories. Unlike Hybrid CI users which were mostly in the pitch-adapting/matched-pitch category, the majority of bimodal CI users were in the latter two categories, pitch-dropping/low-pitch or pitch-unchanging/nonmatched-pitch. Subjects with pitch-adapting

  4. Adaptive sliding mode back-stepping pitch angle control of a variable-displacement pump controlled pitch system for wind turbines.

    PubMed

    Yin, Xiu-xing; Lin, Yong-gang; Li, Wei; Liu, Hong-wei; Gu, Ya-jing

    2015-09-01

    A variable-displacement pump controlled pitch system is proposed to mitigate generator power and flap-wise load fluctuations for wind turbines. The pitch system mainly consists of a variable-displacement hydraulic pump, a fixed-displacement hydraulic motor and a gear set. The hydraulic motor can be accurately regulated by controlling the pump displacement and fluid flows to change the pitch angle through the gear set. The detailed mathematical representation and dynamic characteristics of the proposed pitch system are thoroughly analyzed. An adaptive sliding mode pump displacement controller and a back-stepping stroke piston controller are designed for the proposed pitch system such that the resulting pitch angle tracks its desired value regardless of external disturbances and uncertainties. The effectiveness and control efficiency of the proposed pitch system and controllers have been verified by using realistic dataset of a 750 kW research wind turbine.

  5. A Bayesian Account of Vocal Adaptation to Pitch-Shifted Auditory Feedback

    PubMed Central

    Hahnloser, Richard H. R.

    2017-01-01

    Motor systems are highly adaptive. Both birds and humans compensate for synthetically induced shifts in the pitch (fundamental frequency) of auditory feedback stemming from their vocalizations. Pitch-shift compensation is partial in the sense that large shifts lead to smaller relative compensatory adjustments of vocal pitch than small shifts. Also, compensation is larger in subjects with high motor variability. To formulate a mechanistic description of these findings, we adapt a Bayesian model of error relevance. We assume that vocal-auditory feedback loops in the brain cope optimally with known sensory and motor variability. Based on measurements of motor variability, optimal compensatory responses in our model provide accurate fits to published experimental data. Optimal compensation correctly predicts sensory acuity, which has been estimated in psychophysical experiments as just-noticeable pitch differences. Our model extends the utility of Bayesian approaches to adaptive vocal behaviors. PMID:28135267

  6. Handling Qualities of Model Reference Adaptive Controllers with Varying Complexity for Pitch-Roll Coupled Failures

    NASA Technical Reports Server (NTRS)

    Schaefer, Jacob; Hanson, Curt; Johnson, Marcus A.; Nguyen, Nhan

    2011-01-01

    Three model reference adaptive controllers (MRAC) with varying levels of complexity were evaluated on a high performance jet aircraft and compared along with a baseline nonlinear dynamic inversion controller. The handling qualities and performance of the controllers were examined during failure conditions that induce coupling between the pitch and roll axes. Results from flight tests showed with a roll to pitch input coupling failure, the handling qualities went from Level 2 with the baseline controller to Level 1 with the most complex MRAC tested. A failure scenario with the left stabilator frozen also showed improvement with the MRAC. Improvement in performance and handling qualities was generally seen as complexity was incrementally added; however, added complexity usually corresponds to increased verification and validation effort required for certification. The tradeoff between complexity and performance is thus important to a controls system designer when implementing an adaptive controller on an aircraft. This paper investigates this relation through flight testing of several controllers of vary complexity.

  7. Embedded pitch adapters: A high-yield interconnection solution for strip sensors

    NASA Astrophysics Data System (ADS)

    Ullán, M.; Allport, P. P.; Baca, M.; Broughton, J.; Chisholm, A.; Nikolopoulos, K.; Pyatt, S.; Thomas, J. P.; Wilson, J. A.; Kierstead, J.; Kuczewski, P.; Lynn, D.; Hommels, L. B. A.; Fleta, C.; Fernandez-Tejero, J.; Quirion, D.; Bloch, I.; Díez, S.; Gregor, I. M.; Lohwasser, K.; Poley, L.; Tackmann, K.; Hauser, M.; Jakobs, K.; Kuehn, S.; Mahboubi, K.; Mori, R.; Parzefall, U.; Clark, A.; Ferrere, D.; Gonzalez Sevilla, S.; Ashby, J.; Blue, A.; Bates, R.; Buttar, C.; Doherty, F.; McMullen, T.; McEwan, F.; O'Shea, V.; Kamada, S.; Yamamura, K.; Ikegami, Y.; Nakamura, K.; Takubo, Y.; Unno, Y.; Takashima, R.; Chilingarov, A.; Fox, H.; Affolder, A. A.; Casse, G.; Dervan, P.; Forshaw, D.; Greenall, A.; Wonsak, S.; Wormald, M.; Cindro, V.; Kramberger, G.; Mandić, I.; Mikuž, M.; Gorelov, I.; Hoeferkamp, M.; Palni, P.; Seidel, S.; Taylor, A.; Toms, K.; Wang, R.; Hessey, N. P.; Valencic, N.; Hanagaki, K.; Dolezal, Z.; Kodys, P.; Bohm, J.; Mikestikova, M.; Bevan, A.; Beck, G.; Milke, C.; Domingo, M.; Fadeyev, V.; Galloway, Z.; Hibbard-Lubow, D.; Liang, Z.; Sadrozinski, H. F.-W.; Seiden, A.; To, K.; French, R.; Hodgson, P.; Marin-Reyes, H.; Parker, K.; Jinnouchi, O.; Hara, K.; Bernabeu, J.; Civera, J. V.; Garcia, C.; Lacasta, C.; Marti i Garcia, S.; Rodriguez, D.; Santoyo, D.; Solaz, C.; Soldevila, U.

    2016-09-01

    A proposal to fabricate large area strip sensors with integrated, or embedded, pitch adapters is presented for the End-cap part of the Inner Tracker in the ATLAS experiment. To implement the embedded pitch adapters, a second metal layer is used in the sensor fabrication, for signal routing to the ASICs. Sensors with different embedded pitch adapters have been fabricated in order to optimize the design and technology. Inter-strip capacitance, noise, pick-up, cross-talk, signal efficiency, and fabrication yield have been taken into account in their design and fabrication. Inter-strip capacitance tests taking into account all channel neighbors reveal the important differences between the various designs considered. These tests have been correlated with noise figures obtained in full assembled modules, showing that the tests performed on the bare sensors are a valid tool to estimate the final noise in the full module. The full modules have been subjected to test beam experiments in order to evaluate the incidence of cross-talk, pick-up, and signal loss. The detailed analysis shows no indication of cross-talk or pick-up as no additional hits can be observed in any channel not being hit by the beam above 170 mV threshold, and the signal in those channels is always below 1% of the signal recorded in the channel being hit, above 100 mV threshold. First results on irradiated mini-sensors with embedded pitch adapters do not show any change in the interstrip capacitance measurements with only the first neighbors connected.

  8. Adaptive integral feedback controller for pitch and yaw channels of an AUV with actuator saturations.

    PubMed

    Sarhadi, Pouria; Noei, Abolfazl Ranjbar; Khosravi, Alireza

    2016-11-01

    Input saturations and uncertain dynamics are among the practical challenges in control of autonomous vehicles. Adaptive control is known as a proper method to deal with the uncertain dynamics of these systems. Therefore, incorporating the ability to confront with input saturation in adaptive controllers can be valuable. In this paper, an adaptive autopilot is presented for the pitch and yaw channels of an autonomous underwater vehicle (AUV) in the presence of input saturations. This will be performed by combination of a model reference adaptive control (MRAC) with integral state feedback with a modern anti-windup (AW) compensator. MRAC with integral state feedback is commonly used in autonomous vehicles. However, some proper modifications need to be taken into account in order to cope with the saturation problem. To this end, a Riccati-based anti-windup (AW) compensator is employed. The presented technique is applied to the non-linear six degrees of freedom (DOF) model of an AUV and the obtained results are compared with that of its baseline method. Several simulation scenarios are executed in the pitch and yaw channels to evaluate the controller performance. Moreover, effectiveness of proposed adaptive controller is comprehensively investigated by implementing Monte Carlo simulations. The obtained results verify the performance of proposed method.

  9. An Ad-Hoc Adaptive Pilot Model for Pitch Axis Gross Acquisition Tasks

    NASA Technical Reports Server (NTRS)

    Hanson, Curtis E.

    2012-01-01

    An ad-hoc algorithm is presented for real-time adaptation of the well-known crossover pilot model and applied to pitch axis gross acquisition tasks in a generic fighter aircraft. Off-line tuning of the crossover model to human pilot data gathered in a fixed-based high fidelity simulation is first accomplished for a series of changes in aircraft dynamics to provide expected values for model parameters. It is shown that in most cases, for this application, the traditional crossover model can be reduced to a gain and a time delay. The ad-hoc adaptive pilot gain algorithm is shown to have desirable convergence properties for most types of changes in aircraft dynamics.

  10. Field testing of feedforward collective pitch control on the CART2 using a nacelle-based Lidar scanner

    SciTech Connect

    Schlipf, David; Fleming, Paul; Haizmann, Florian; Scholbrock, Andrew; Hofsass, Martin; Wright, Alan; Cheng, Po Wen

    2014-12-16

    This work presents the results from a field test of LIDAR assisted collective pitch control using a scanning LIDAR device installed on the nacelle of a mid-scale research turbine. A nonlinear feedforward controller is extended by an adaptive filter to remove all uncorrelated frequencies of the wind speed measurement to avoid unnecessary control action. Positive effects on the rotor speed regulation as well as on tower, blade and shaft loads have been observed in the case that the previous measured correlation and timing between the wind preview and the turbine reaction are accomplish. The feedforward controller had negative impact, when the LIDAR measurement was disturbed by obstacles in front of the turbine. This work proves, that LIDAR is valuable tool for wind turbine control not only in simulations but also under real conditions. Moreover, the paper shows that further understanding of the relationship between the wind measurement and the turbine reaction is crucial to improve LIDAR assisted control of wind turbines.

  11. Field Testing of Feedforward Collective Pitch Control on the CART2 Using a Nacelle-Based Lidar Scanner

    NASA Astrophysics Data System (ADS)

    Schlipf, David; Fleming, Paul; Haizmann, Florian; Scholbrock, Andrew; Hofsäß, Martin; Wright, Alan; Cheng, Po Wen

    2014-12-01

    This work presents the results from a field test of LIDAR assisted collective pitch control using a scanning LIDAR device installed on the nacelle of a mid-scale research turbine. A nonlinear feedforward controller is extended by an adaptive filter to remove all uncorrelated frequencies of the wind speed measurement to avoid unnecessary control action. Positive effects on the rotor speed regulation as well as on tower, blade and shaft loads have been observed in the case that the previous measured correlation and timing between the wind preview and the turbine reaction are accomplish. The feedforward controller had negative impact, when the LIDAR measurement was disturbed by obstacles in front of the turbine. This work proves, that LIDAR is valuable tool for wind turbine control not only in simulations but also under real conditions. Furthermore, the paper shows that further understanding of the relationship between the wind measurement and the turbine reaction is crucial to improve LIDAR assisted control of wind turbines.

  12. Adaptive Potential of Maritime Pine (Pinus pinaster) Populations to the Emerging Pitch Canker Pathogen, Fusarium circinatum

    PubMed Central

    Elvira-Recuenco, Margarita; Iturritxa, Eugenia; Majada, Juan; Alia, Ricardo; Raposo, Rosa

    2014-01-01

    There is a concern on how emerging pests and diseases will affect the distribution range and adaptability of their host species, especially due to different conditions derived from climate change and growing globalization. Fusarium circinatum, which causes pitch canker disease in Pinus species, is an exotic pathogen of recent introduction in Spain that threatens its maritime pine (P. pinaster) stands. To predict the impact this disease will have on the species, we examine host resistance traits and their genetic architecture. Resistance phenotyping was done in a clonal provenance/progeny trial, using three-year-old cuttings artificially inoculated with the pathogen and maintained under controlled environmental conditions. A total number of 670 ramets were assessed, distributed in 10 populations, with a total of 47 families, 2 to 5 half-sibs per family, and 3–7 ramets per clone. High genetic variation was found at the three hierarchical levels studied: population, family and clone, being both additive and non-additive effects important. Narrow-sense and broad-sense heritability estimates were relatively high, with respective values of 0.43–0.58 and 0.51–0.8, depending on the resistance traits measured (lesion length, lesion length rate, time to wilting, and survival). These values suggest the species' high capacity of evolutionary response to the F. circinatum pathogen. A population originated in Northern Spain was the most resistant, while another from Morocco was the most susceptible. The total number of plants that did not show lesion development or presented a small lesion (length<30 mm) was 224 out of 670, indicating a high proportion of resistant trees in the offspring within the analyzed populations. We found large differences among populations and considerable genetic variation within populations, which should allow, through natural or artificial selection, the successful adaptation of maritime pine to pitch canker disease. PMID:25500822

  13. Adaptive potential of maritime pine (Pinus pinaster) populations to the emerging pitch canker pathogen, Fusarium circinatum.

    PubMed

    Elvira-Recuenco, Margarita; Iturritxa, Eugenia; Majada, Juan; Alia, Ricardo; Raposo, Rosa

    2014-01-01

    There is a concern on how emerging pests and diseases will affect the distribution range and adaptability of their host species, especially due to different conditions derived from climate change and growing globalization. Fusarium circinatum, which causes pitch canker disease in Pinus species, is an exotic pathogen of recent introduction in Spain that threatens its maritime pine (P. pinaster) stands. To predict the impact this disease will have on the species, we examine host resistance traits and their genetic architecture. Resistance phenotyping was done in a clonal provenance/progeny trial, using three-year-old cuttings artificially inoculated with the pathogen and maintained under controlled environmental conditions. A total number of 670 ramets were assessed, distributed in 10 populations, with a total of 47 families, 2 to 5 half-sibs per family, and 3-7 ramets per clone. High genetic variation was found at the three hierarchical levels studied: population, family and clone, being both additive and non-additive effects important. Narrow-sense and broad-sense heritability estimates were relatively high, with respective values of 0.43-0.58 and 0.51-0.8, depending on the resistance traits measured (lesion length, lesion length rate, time to wilting, and survival). These values suggest the species' high capacity of evolutionary response to the F. circinatum pathogen. A population originated in Northern Spain was the most resistant, while another from Morocco was the most susceptible. The total number of plants that did not show lesion development or presented a small lesion (length<30 mm) was 224 out of 670, indicating a high proportion of resistant trees in the offspring within the analyzed populations. We found large differences among populations and considerable genetic variation within populations, which should allow, through natural or artificial selection, the successful adaptation of maritime pine to pitch canker disease.

  14. A modulatory effect of male voice pitch on long-term memory in women: evidence of adaptation for mate choice?

    PubMed

    Smith, David S; Jones, Benedict C; Feinberg, David R; Allan, Kevin

    2012-01-01

    From a functionalist perspective, human memory should be attuned to information of adaptive value for one's survival and reproductive fitness. While evidence of sensitivity to survival-related information is growing, specific links between memory and information that could impact upon reproductive fitness have remained elusive. Here, in two experiments, we showed that memory in women is sensitive to male voice pitch, a sexually dimorphic cue important for mate choice because it not only serves as an indicator of genetic quality, but may also signal behavioural traits undesirable in a long-term partner. In Experiment 1, we report that women's visual object memory is significantly enhanced when an object's name is spoken during encoding in a masculinised (i.e., lower-pitch) versus feminised (i.e., higher-pitch) male voice, but that no analogous effect occurs when women listen to other women's voices. Experiment 2 replicated this pattern of results, additionally showing that lowering and raising male voice pitch enhanced and impaired women's memory, respectively, relative to a baseline (i.e., unmanipulated) voice condition. The modulatory effect of sexual dimorphism cues in the male voice may reveal a mate-choice adaptation within women's memory, sculpted by evolution in response to the dilemma posed by the double-edged qualities of male masculinity.

  15. Handling Qualities Evaluations of Low Complexity Model Reference Adaptive Controllers for Reduced Pitch and Roll Damping Scenarios

    NASA Technical Reports Server (NTRS)

    Hanson, Curt; Schaefer, Jacob; Burken, John J.; Johnson, Marcus; Nguyen, Nhan

    2011-01-01

    National Aeronautics and Space Administration (NASA) researchers have conducted a series of flight experiments designed to study the effects of varying levels of adaptive controller complexity on the performance and handling qualities of an aircraft under various simulated failure or damage conditions. A baseline, nonlinear dynamic inversion controller was augmented with three variations of a model reference adaptive control design. The simplest design consisted of a single adaptive parameter in each of the pitch and roll axes computed using a basic gradient-based update law. A second design was built upon the first by increasing the complexity of the update law. The third and most complex design added an additional adaptive parameter to each axis. Flight tests were conducted using NASA s Full-scale Advanced Systems Testbed, a highly modified F-18 aircraft that contains a research flight control system capable of housing advanced flight controls experiments. Each controller was evaluated against a suite of simulated failures and damage ranging from destabilization of the pitch and roll axes to significant coupling between the axes. Two pilots evaluated the three adaptive controllers as well as the non-adaptive baseline controller in a variety of dynamic maneuvers and precision flying tasks designed to uncover potential deficiencies in the handling qualities of the aircraft, and adverse interactions between the pilot and the adaptive controllers. The work was completed as part of the Integrated Resilient Aircraft Control Project under NASA s Aviation Safety Program.

  16. Field testing of feedforward collective pitch control on the CART2 using a nacelle-based Lidar scanner

    DOE PAGES

    Schlipf, David; Fleming, Paul; Haizmann, Florian; ...

    2014-12-16

    This work presents the results from a field test of LIDAR assisted collective pitch control using a scanning LIDAR device installed on the nacelle of a mid-scale research turbine. A nonlinear feedforward controller is extended by an adaptive filter to remove all uncorrelated frequencies of the wind speed measurement to avoid unnecessary control action. Positive effects on the rotor speed regulation as well as on tower, blade and shaft loads have been observed in the case that the previous measured correlation and timing between the wind preview and the turbine reaction are accomplish. The feedforward controller had negative impact, whenmore » the LIDAR measurement was disturbed by obstacles in front of the turbine. This work proves, that LIDAR is valuable tool for wind turbine control not only in simulations but also under real conditions. Moreover, the paper shows that further understanding of the relationship between the wind measurement and the turbine reaction is crucial to improve LIDAR assisted control of wind turbines.« less

  17. Evaluation of pitch up of two-axle solid waste collection compactor trucks in the static condition.

    PubMed

    Souza, Rosilene Viana de Freitas; Pinto, João Mário Andrade; Cimini, Carlos Alberto; Pereira, Sérgio Luiz de Souza

    2011-03-01

    The study of pitch up limit for solid waste collection compactor trucks in tilted public roads is of great relevance both for the planning of waste collection, mainly in cities with very uneven street gradient, or for use as a design parameter in projects involving public roads. Considering the typical construction and use of rear loader waste compactor equipment, the centre of gravity moves towards the rear of the vehicle as it is loaded, resulting in overload in the rear axle at the end of the waste collection period. In the city of Belo Horizonte (Brazil), several cases of pitch up have been reported for this type of vehicle, in streets with different inclinations and with loading situations in which the load box was not completely full. The present study investigated the variation of the imminence pitch up angles of the two-axle, rear-loading, solid waste collection compactor truck in a static condition, determined by the variation of its centre of gravity coordinates, which were obtained experimentally by means of a testing programme for different loading situations. The critical inclination angle was 0.347 rad (19.89°), which corresponds to a ramp inclination of 36.17%, for the condition of total weight of 157.06 kN (16 027 kgf) with payload of 63.42 kN (6472 kgf).

  18. Response of Rotor Lift to an Increase in Collective Pitch in the Case of Descending Flight, the Regime of the Rotor Being Near Autorotation

    NASA Technical Reports Server (NTRS)

    Valensi, Jacques; Rebont, Jean; Soulez-Lariviere, Jean

    1960-01-01

    An elementary calculation inspired by the classic treatment for the steady state permits the determination of the induced velocity and the overall lift of the rotor as a function of the collective pitch for all values of the advance per turn. The nature of the lift response is shown to be essentially a function of the rate of pitch change.

  19. Accuracy and adaptation of reaching and pointing in pitched visual environments

    NASA Technical Reports Server (NTRS)

    Welch, R. B.; Post, R. B.

    1996-01-01

    Visually perceived eye level (VPEL) and the ability of subjects to reach with an unseen limb to targets placed at VPEL were measured in a statically pitched visual surround (pitchroom). VPEL was shifted upward and downward by upward and downward room pitch, respectively. Accuracy in reaching to VPEL represented a compromise between VPEL and actual eye level. This indicates that VPEL shifts reflect in part a change in perceived location of objects. When subjects were provided with terminal visual feedback about their reaching, accuracy improved rapidly. Subsequent reaching, with the room vertical, revealed a negative aftereffect (i.e., reaching errors that were opposite those made initially in the pitched room). In a second study, pointing accuracy was assessed for targets located both at VPEL and at other positions. Errors were similar for targets whether located at VPEL or elsewhere. Additionally, pointing responses were restricted to a narrower range than that of the actual target locations. The small size of reaching and pointing errors in both studies suggests that factors other than a change in perceived location are also involved in VPEL shifts.

  20. Pitch perception.

    PubMed

    Yost, William A

    2009-11-01

    This article is a review of the psychophysical study of pitch perception. The history of the study of pitch has seen a continual competition between spectral and temporal theories of pitch perception. The pitch of complex stimuli is likely based on the temporal regularities in a sound's waveform, with the strongest pitches occurring for stimuli with low-frequency components. Thus, temporal models, especially those based on autocorrelation-like processes, appear to account for the majority of the data.

  1. Context-specific adaptation of the gain of the oculomotor response to lateral translation using roll and pitch head tilts as contexts

    NASA Technical Reports Server (NTRS)

    Shelhamer, Mark; Peng, Grace C Y.; Ramat, Stefano; Patel, Vivek

    2002-01-01

    Previous studies established that vestibular and oculomotor behaviors can have two adapted states (e.g., gain) simultaneously, and that a context cue (e.g., vertical eye position) can switch between the two states. The present study examined this phenomenon of context-specific adaptation for the oculomotor response to interaural translation (which we term "linear vestibulo-ocular reflex" or LVOR even though it may have extravestibular components). Subjects sat upright on a linear sled and were translated at 0.7 Hz and 0.3 gpeak acceleration while a visual-vestibular mismatch paradigm was used to adaptively increase (x2) or decrease (x0) the gain of the LVOR. In each experimental session, gain increase was asked for in one context, and gain decrease in another context. Testing in darkness with steps and sines before and after adaptation, in each context, assessed the extent to which the context itself could recall the gain state that was imposed in that context during adaptation. Two different contexts were used: head pitch (26 degrees forward and backward) and head roll (26 degrees or 45 degrees, right and left). Head roll tilt worked well as a context cue: with the head rolled to the right the LVOR could be made to have a higher gain than with the head rolled to the left. Head pitch tilt was less effective as a context cue. This suggests that the more closely related a context cue is to the response being adapted, the more effective it is.

  2. Consonance and pitch.

    PubMed

    McLachlan, Neil; Marco, David; Light, Maria; Wilson, Sarah

    2013-11-01

    To date, no consensus exists in the literature as to theories of consonance and dissonance. Experimental data collected over the last century have raised questions about the dominant theories that are based on frequency relationships between the harmonics of music chords. This study provides experimental evidence that strongly challenges these theories and suggests a new theory of dissonance based on relationships between pitch perception and recognition. Experiment 1 shows that dissonance does not increase with increasing numbers of harmonics in chords as predicted by Helmholtz's (1863/1954) roughness theory, nor does it increase with fewer pitch-matching errors as predicted by Stumpf's (1898) tonal fusion theory. Dissonance was strongly correlated with pitch-matching error for chords, which in turn was reduced by chord familiarity and greater music training. This led to the proposition that long-term memory templates for common chords assist the perception of pitches in chords by providing an estimate of the chord intervals from spectral information. When recognition mechanisms based on these templates fail, the spectral pitch estimate is inconsistent with the period of the waveform, leading to cognitive incongruence and the negative affect of dissonance. The cognitive incongruence theory of dissonance was rigorously tested in Experiment 2, in which nonmusicians were trained to match the pitches of a random selection of 2-pitch chords. After 10 training sessions, they rated the chords they had learned to pitch match as less dissonant than the unlearned chords, irrespective of their tuning, providing strong support for a cognitive mechanism of dissonance.

  3. Particle Swarm Based Collective Searching Model for Adaptive Environment

    SciTech Connect

    Cui, Xiaohui; Patton, Robert M; Potok, Thomas E; Treadwell, Jim N

    2008-01-01

    This report presents a pilot study of an integration of particle swarm algorithm, social knowledge adaptation and multi-agent approaches for modeling the collective search behavior of self-organized groups in an adaptive environment. The objective of this research is to apply the particle swarm metaphor as a model of social group adaptation for the dynamic environment and to provide insight and understanding of social group knowledge discovering and strategic searching. A new adaptive environment model, which dynamically reacts to the group collective searching behaviors, is proposed in this research. The simulations in the research indicate that effective communication between groups is not the necessary requirement for whole self-organized groups to achieve the efficient collective searching behavior in the adaptive environment.

  4. Particle Swarm Based Collective Searching Model for Adaptive Environment

    SciTech Connect

    Cui, Xiaohui; Patton, Robert M; Potok, Thomas E; Treadwell, Jim N

    2007-01-01

    This report presents a pilot study of an integration of particle swarm algorithm, social knowledge adaptation and multi-agent approaches for modeling the collective search behavior of self-organized groups in an adaptive environment. The objective of this research is to apply the particle swarm metaphor as a model of social group adaptation for the dynamic environment and to provide insight and understanding of social group knowledge discovering and strategic searching. A new adaptive environment model, which dynamically reacts to the group collective searching behaviors, is proposed in this research. The simulations in the research indicate that effective communication between groups is not the necessary requirement for whole self-organized groups to achieve the efficient collective searching behavior in the adaptive environment.

  5. Pitch Fractionation.

    DTIC Science & Technology

    1981-12-15

    13 3. Solvent Fractionation Experiments .................................... 15 4. Fourier Transform Infrared Spectra for A240 Petrolem Pitch AG 12...34 and Mesophase Pitch AG 164B ............................... 21 5. Fourier Transform Infrared Spectra ................................... 23 6...compared by Fourier transform infrared (FTIR) analysis using a Digilab Model FTS 14 spectrophotometer (Rockwell International, Anaheim, California

  6. Adaptive robust control of a class of non-affine variable-speed variable-pitch wind turbines with unmodeled dynamics.

    PubMed

    Bagheri, Pedram; Sun, Qiao

    2016-07-01

    In this paper, a novel synthesis of Nussbaum-type functions, and an adaptive radial-basis function neural network is proposed to design controllers for variable-speed, variable-pitch wind turbines. Dynamic equations of the wind turbine are highly nonlinear, uncertain, and affected by unknown disturbance sources. Furthermore, the dynamic equations are non-affine with respect to the pitch angle, which is a control input. To address these problems, a Nussbaum-type function, along with a dynamic control law are adopted to resolve the non-affine nature of the equations. Moreover, an adaptive radial-basis function neural network is designed to approximate non-parametric uncertainties. Further, the closed-loop system is made robust to unknown disturbance sources, where no prior knowledge of disturbance bound is assumed in advance. Finally, the Lyapunov stability analysis is conducted to show the stability of the entire closed-loop system. In order to verify analytical results, a simulation is presented and the results are compared to both a PI and an existing adaptive controllers.

  7. Linking Individual and Collective Behavior in Adaptive Social Networks

    NASA Astrophysics Data System (ADS)

    Pinheiro, Flávio L.; Santos, Francisco C.; Pacheco, Jorge M.

    2016-03-01

    Adaptive social structures are known to promote the evolution of cooperation. However, up to now the characterization of the collective, population-wide dynamics resulting from the self-organization of individual strategies on a coevolving, adaptive network has remained unfeasible. Here we establish a (reversible) link between individual (micro)behavior and collective (macro)behavior for coevolutionary processes. We demonstrate that an adaptive network transforms a two-person social dilemma locally faced by individuals into a collective dynamics that resembles that associated with an N -person coordination game, whose characterization depends sensitively on the relative time scales between the entangled behavioral and network evolutions. In particular, we show that the faster the relative rate of adaptation of the network, the smaller the critical fraction of cooperators required for cooperation to prevail, thus establishing a direct link between network adaptation and the evolution of cooperation. The framework developed here is general and may be readily applied to other dynamical processes occurring on adaptive networks, notably, the spreading of contagious diseases or the diffusion of innovations.

  8. Extending wind turbine operational conditions; a comparison of set point adaptation and LQG individual pitch control for highly turbulent wind

    NASA Astrophysics Data System (ADS)

    Engels, W. P.; Subhani, S.; Zafar, H.; Savenije, F.

    2014-06-01

    Extreme wind conditions can cause excessive loading on the turbine. This not only results in higher design loads, but when these conditions occur in practice, will also result in higher maintenance cost. Although there are already effective methods of dealing with gusts, other extreme conditions should also be examined. More specifically, extreme turbulence conditions (e.g. those specified by design load case 1.3 in IEC61400-1 ed. 3) require special attention as they can lead to design-driving extreme loads on blades, tower and other wind turbine components. This paper examines two methods to deal with extreme loads in a case of extreme turbulent wind. One method is derating the turbine, the other method is an individual pitch control (IPC) algorithm. Derating of the turbine can be achieved in two ways, one is changing the rated torque, the other is changing the rated rotor speed. The effect of these methods on fatigue loads and extreme loads is examined. Non-linear aero-elastic simulations using Phatas, show that reducing the rated rotor speed is far more effective at reducing the loads than reducing torque. Then, the IPC algorithm is proposed. This algorithm is a linear quadratic Gaussian (LQG) controller based on a time invariant model, defined in the fixed reference frame that includes the first tower and blade modes. Because this method takes the dynamics of the system into account more than conventional IPC control, it is expected that these loads dealt with more effectively, when they are particularly relevant. It is expected that in extreme turbulent the blade and tower dynamics are indeed more relevant. The effect of this algorithm on fatigue loads and pitch effort is examined and compared with the fatigue loads and pitch effort of reference IPC. Finally, the methods are compared in non-linear aero-elastic simulations with extreme turbulent wind.

  9. The adaptive drop foot stimulator - Multivariable learning control of foot pitch and roll motion in paretic gait.

    PubMed

    Seel, Thomas; Werner, Cordula; Schauer, Thomas

    2016-11-01

    Many stroke patients suffer from the drop foot syndrome, which is characterized by a limited ability to lift (the lateral and/or medial edge of) the foot and leads to a pathological gait. In this contribution, we consider the treatment of this syndrome via functional electrical stimulation (FES) of the peroneal nerve during the swing phase of the paretic foot. A novel three-electrodes setup allows us to manipulate the recruitment of m. tibialis anterior and m. fibularis longus via two independent FES channels without violating the zero-net-current requirement of FES. We characterize the domain of admissible stimulation intensities that results from the nonlinearities in patients' stimulation intensity tolerance. To compensate most of the cross-couplings between the FES intensities and the foot motion, we apply a nonlinear controller output mapping. Gait phase transitions as well as foot pitch and roll angles are assessed in realtime by means of an Inertial Measurement Unit (IMU). A decentralized Iterative Learning Control (ILC) scheme is used to adjust the stimulation to the current needs of the individual patient. We evaluate the effectiveness of this approach in experimental trials with drop foot patients walking on a treadmill and on level ground. Starting from conventional stimulation parameters, the controller automatically determines individual stimulation parameters and thus achieves physiological foot pitch and roll angle trajectories within at most two strides.

  10. Adaptive network dynamics and evolution of leadership in collective migration

    NASA Astrophysics Data System (ADS)

    Pais, Darren; Leonard, Naomi E.

    2014-01-01

    The evolution of leadership in migratory populations depends not only on costs and benefits of leadership investments but also on the opportunities for individuals to rely on cues from others through social interactions. We derive an analytically tractable adaptive dynamic network model of collective migration with fast timescale migration dynamics and slow timescale adaptive dynamics of individual leadership investment and social interaction. For large populations, our analysis of bifurcations with respect to investment cost explains the observed hysteretic effect associated with recovery of migration in fragmented environments. Further, we show a minimum connectivity threshold above which there is evolutionary branching into leader and follower populations. For small populations, we show how the topology of the underlying social interaction network influences the emergence and location of leaders in the adaptive system. Our model and analysis can be extended to study the dynamics of collective tracking or collective learning more generally. Thus, this work may inform the design of robotic networks where agents use decentralized strategies that balance direct environmental measurements with agent interactions.

  11. Adaptive collective foraging in groups with conflicting nutritional needs.

    PubMed

    Senior, Alistair M; Lihoreau, Mathieu; Charleston, Michael A; Buhl, Jerome; Raubenheimer, David; Simpson, Stephen J

    2016-04-01

    Collective foraging, based on positive feedback and quorum responses, is believed to improve the foraging efficiency of animals. Nutritional models suggest that social information transfer increases the ability of foragers with closely aligned nutritional needs to find nutrients and maintain a balanced diet. However, whether or not collective foraging is adaptive in a heterogeneous group composed of individuals with differing nutritional needs is virtually unexplored. Here we develop an evolutionary agent-based model using concepts of nutritional ecology to address this knowledge gap. Our aim was to evaluate how collective foraging, mediated by social retention on foods, can improve nutrient balancing in individuals with different requirements. The model suggests that in groups where inter-individual nutritional needs are unimodally distributed, high levels of collective foraging yield optimal individual fitness by reducing search times that result from moving between nutritionally imbalanced foods. However, where nutritional needs are highly bimodal (e.g. where the requirements of males and females differ) collective foraging is selected against, leading to group fission. In this case, additional mechanisms such as assortative interactions can coevolve to allow collective foraging by subgroups of individuals with aligned requirements. Our findings indicate that collective foraging is an efficient strategy for nutrient regulation in animals inhabiting complex nutritional environments and exhibiting a range of social forms.

  12. Adaptive collective foraging in groups with conflicting nutritional needs

    PubMed Central

    Senior, Alistair M.; Lihoreau, Mathieu; Charleston, Michael A.; Buhl, Jerome; Raubenheimer, David; Simpson, Stephen J.

    2016-01-01

    Collective foraging, based on positive feedback and quorum responses, is believed to improve the foraging efficiency of animals. Nutritional models suggest that social information transfer increases the ability of foragers with closely aligned nutritional needs to find nutrients and maintain a balanced diet. However, whether or not collective foraging is adaptive in a heterogeneous group composed of individuals with differing nutritional needs is virtually unexplored. Here we develop an evolutionary agent-based model using concepts of nutritional ecology to address this knowledge gap. Our aim was to evaluate how collective foraging, mediated by social retention on foods, can improve nutrient balancing in individuals with different requirements. The model suggests that in groups where inter-individual nutritional needs are unimodally distributed, high levels of collective foraging yield optimal individual fitness by reducing search times that result from moving between nutritionally imbalanced foods. However, where nutritional needs are highly bimodal (e.g. where the requirements of males and females differ) collective foraging is selected against, leading to group fission. In this case, additional mechanisms such as assortative interactions can coevolve to allow collective foraging by subgroups of individuals with aligned requirements. Our findings indicate that collective foraging is an efficient strategy for nutrient regulation in animals inhabiting complex nutritional environments and exhibiting a range of social forms. PMID:27152206

  13. Adaptive 3D Face Reconstruction from Unconstrained Photo Collections.

    PubMed

    Roth, Joseph; Tong, Yiying; Liu, Xiaoming

    2016-12-07

    Given a photo collection of "unconstrained" face images of one individual captured under a variety of unknown pose, expression, and illumination conditions, this paper presents a method for reconstructing a 3D face surface model of the individual along with albedo information. Unlike prior work on face reconstruction that requires large photo collections, we formulate an approach to adapt to photo collections with a high diversity in both the number of images and the image quality. To achieve this, we incorporate prior knowledge about face shape by fitting a 3D morphable model to form a personalized template, following by using a novel photometric stereo formulation to complete the fine details, under a coarse-to-fine scheme. Our scheme incorporates a structural similarity-based local selection step to help identify a common expression for reconstruction while discarding occluded portions of faces. The evaluation of reconstruction performance is through a novel quality measure, in the absence of ground truth 3D scans. Superior large-scale experimental results are reported on synthetic, Internet, and personal photo collections.

  14. An examination of slo-pitch pitching trajectories.

    PubMed

    Wu, Tom; Gervais, Pierre

    2008-01-01

    Many slo-pitch coaches and players believe that generating spin on a ball can affect its trajectory. The influence of air resistance on a ball that is thrown at a moderate speed and spin is unclear. The aim of this study was to examine the influence of spin on the ball's trajectory in slo-pitch pitching using both experimental results and ball flight simulations. Fourteen pitchers participated in the study, each of whom threw five backspin and topspin pitches each. Data were collected using standard three-dimensional videography. The horizontal velocity, vertical velocity, angular velocity, release height, and horizontal displacement of the backspin pitches were significantly higher than those of the topspin pitches. The ball flight simulations were developed to examine the influence of the ball spin, and it was concluded that the spin of the ball had a significant effect on the ball's vertical and horizontal displacements. Furthermore, our results suggest that a backspin pitch that reaches the maximum height allowable and lands in the front edge of the strike zone has the steepest slope. The present results add to our understanding of projectile motion and aerodynamics.

  15. 76 FR 63354 - Proposed Information Collection (Application in Acquiring Specially Adapted Housing or Special...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-12

    ... Information Collection (Application in Acquiring Specially Adapted Housing or Special Home Adaptation Grant... adapted housing or special home adaptation grant. DATES: Written comments and recommendations on the... Housing or Special Home Adaptation Grant, VA Form 26-4555. OMB Control Number: 2900-0132. Type of...

  16. Variable pitch propeller

    NASA Technical Reports Server (NTRS)

    Pistolesi, Enrico

    1923-01-01

    The advantages of variable pitch propellers over constant pitch propellers is presented along with different methods of varying the pitch. The technique of varying the shape of the propeller is presented as the most efficient one.

  17. 77 FR 323 - Agency Information Collection (Application in Acquiring Specially Adapted Housing or Special Home...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-04

    ... Adaptation Grant) Activity Under OMB Review AGENCY: Veterans Benefits Administration, Department of Veterans... Adapted Housing or Special Home Adaptation Grant, VA Form 26-4555. OMB Control Number: 2900-0132. Type of... special home adaptation grant. VA will use the data collected to determine the veteran's eligibility....

  18. Graphite Fibers from Pitch

    DTIC Science & Technology

    1975-07-01

    carbon fibers derived from pitch (Type-P fibers). But even if such perfect mesophase pitch fibers could be obtained, the subsequent carbonization... mesophase pitch filaments with diameters below lOfim was demonstrated in the preceding contract period. Further effort was aimed at reproducibly...Isotropie pitch fibers. ’ It seemed prudent for us to establish whether some of these agents could be used to advantage with the mesophase pitch

  19. 76 FR 44402 - Proposed Information Collection (Application for Automobile or Other Conveyance and Adaptive...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-25

    ... AFFAIRS Proposed Information Collection (Application for Automobile or Other Conveyance and Adaptive...' eligibility for automobile adaptation equipment or other conveyance allowance. DATES: Written comments and... techniques or the use of other forms of information technology. Title: Application for Automobile or...

  20. Dormant mesophase pitch

    SciTech Connect

    Otani, S.

    1984-09-18

    A novel carbonaceous pitch which is optically isotropic in nature and which turns into optically anisotropic when shear forces are applied thereto. The carbonaceous pitch may be obtained by hydrogenating the mesophase of a mesophase pitch to the extent that the mesophase is rendered soluble in quinoline. The carbonaceous pitch is used as a binder and an impregnator and as a precursor material for a highly oriented, high-strength and high-modulus carbon fiber, needle coke or the like carbonaceous materials.

  1. High anisotropic pitch

    SciTech Connect

    Dickakian, G. B.

    1985-11-05

    An improved process for preparing an optically anisotropic pitch which comprises heating a pitch feed material at a temperature within the range of about 350/sup 0/ C. to 450/sup 0/ C. while passing an inert gas therethrough at a rate of at least 2.5 SCFH/lb of pitch feed material and agitating said pitch feed material at a stirrer rate of from about 500 to 600 rpm to obtain an essentially 100% mesophase pitch product suitable for carbon production.

  2. Adaptive Control of a Utility-Scale Wind Turbine Operating in Region 3

    NASA Technical Reports Server (NTRS)

    Frost, Susan A.; Balas, Mark J.; Wright, Alan D.

    2009-01-01

    Adaptive control techniques are well suited to nonlinear applications, such as wind turbines, which are difficult to accurately model and which have effects from poorly known operating environments. The turbulent and unpredictable conditions in which wind turbines operate create many challenges for their operation. In this paper, we design an adaptive collective pitch controller for a high-fidelity simulation of a utility scale, variable-speed horizontal axis wind turbine. The objective of the adaptive pitch controller in Region 3 is to regulate generator speed and reject step disturbances. The control objective is accomplished by collectively pitching the turbine blades. We use an extension of the Direct Model Reference Adaptive Control (DMRAC) approach to track a reference point and to reject persistent disturbances. The turbine simulation models the Controls Advanced Research Turbine (CART) of the National Renewable Energy Laboratory in Golden, Colorado. The CART is a utility-scale wind turbine which has a well-developed and extensively verified simulator. The adaptive collective pitch controller for Region 3 was compared in simulations with a bas celliansesical Proportional Integrator (PI) collective pitch controller. In the simulations, the adaptive pitch controller showed improved speed regulation in Region 3 when compared with the baseline PI pitch controller and it demonstrated robustness to modeling errors.

  3. Memory for pitch in congenital amusia: beyond a fine-grained pitch discrimination problem.

    PubMed

    Williamson, Victoria Jane; Stewart, Lauren

    2010-08-01

    Congenital amusia is a disorder that affects the perception and production of music. While amusia has been associated with deficits in pitch discrimination, several reports suggest that memory deficits also play a role. The present study investigated short-term memory span for pitch-based and verbal information in 14 individuals with amusia and matched controls. Analogous adaptive-tracking procedures were used to generate tone and digit spans using stimuli that exceeded psychophysically measured pitch perception thresholds. Individuals with amusia had significantly smaller tone spans, whereas their digits spans were a similar size to those of controls. An automated operation span task was used to determine working memory capacity. Working memory deficits were seen in only a small subgroup of individuals with amusia. These findings support the existence of a pitch-specific component within short-term memory and suggest that congenital amusia is more than a disorder of fine-grained pitch discrimination.

  4. Process for isolating mesophase pitch

    SciTech Connect

    Romine, H.E.; McConaghy, J.R. Jr.

    1991-07-16

    This patent describes a process for the preparation of mesophase pitch. It comprises combining an isotropic pitch containing mesogens with a solvent, effecting phase separation of the mesogens from the isotropic pitch under solvent supercritical conditions of temperature and pressure, wherein the mesogens associate together under solvent supercritical conditions of temperature and pressure to form mesophase pitch; and recovering mesophase pitch.

  5. High coking value pitch

    DOEpatents

    Miller, Douglas J.; Chang, Ching-Feng; Lewis, Irwin C.; Lewis, Richard T.

    2014-06-10

    A high coking value pitch prepared from coal tar distillate and has a low softening point and a high carbon value while containing substantially no quinoline insolubles is disclosed. The pitch can be used as an impregnant or binder for producing carbon and graphite articles.

  6. Methods for producing mesophase pitch binder pitch

    SciTech Connect

    Lewis, I.C.

    1984-02-14

    A method of producing a pitch or a coke, comprising reacting an aromatic hydrocarbon with anhydrous AlCl/sub 3/ and an acid salt of an organic amine which acid salt reduces the activity of the AlCl/sub 3/, and is miscible with the AlCl/sub 3/ to form a molten eutectic salt mixture reactive with the aromatic hydrocarbon.

  7. Adapting a Methodology from Mathematics Education Research to Chemistry Education Research: Documenting Collective Activity

    ERIC Educational Resources Information Center

    Cole, Renee; Becker, Nicole; Towns, Marcy; Sweeney, George; Wawro, Megan; Rasmussen, Chris

    2012-01-01

    In this report, we adapt and extend a methodology for documenting the collective production of meaning in a classroom community. A cornerstone of the methodological approach that we develop is a close examination of classroom discourse. Our efforts to analyze the collective production of meaning by examining classroom interaction are compatible…

  8. Octave Bias in Pitch Perception: The Influence of Pitch Height on Pitch Class Identification.

    PubMed

    Prpic, Valter; Murgia, Mauro; De Tommaso, Matteo; Boschetti, Giulia; Galmonte, Alessandra; Agostini, Tiziano

    2016-09-01

    Pitch height and pitch class are different, but strictly related, percepts of music tones. To investigate the influence of pitch height in a pitch class identification task, we systematically analyzed the errors-in terms of direction and amount-committed by a group of musicians. The aim of our study was to verify the existence of constant errors in the identification of pitch classes across consecutive octaves. Stimuli were single piano tones from the C major scale executed in two consecutive octaves. Participants showed different response patterns in the two octaves. The direction of errors revealed a constant tendency to underestimate pitch classes in the lowest octave and to overestimate pitch classes in the highest octave. Thus, pitch height showed to influence pitch class identification. We called this bias "pitch class polarization", since the same pitch class was judged to be respectively lower and higher, depending on relatively low or high pitch height.

  9. Pitch fractionation. Technical report

    SciTech Connect

    Weinberg, V.L.; White, J.L.

    1981-12-15

    Petroleum pitch (Ashland A240) has been subjected to thermal treatment and solvent fractionation to produce refined pitches to be evaluated as impregnants for carbon-carbon composites. The solvent fractions were obtained by sequential Soxhlet extraction with solvents such as hexane, cyclohexane, toluene, and pyridine. The most severe thermal treatment produced a mesophase pitch (approximately 50% mesophase); an appreciable portion of the mesophase was soluble in strong solvents. There were substantial differences in chemical composition and in pyrolysis behavior of the fractions. As the depth of fraction increased, the pyrolysis yield and bloating increased, and the microstructure of the coke became finer until glassy microconstituents were formed in the deepest fractions.

  10. Adaptive Sampling-Based Information Collection for Wireless Body Area Networks.

    PubMed

    Xu, Xiaobin; Zhao, Fang; Wang, Wendong; Tian, Hui

    2016-08-31

    To collect important health information, WBAN applications typically sense data at a high frequency. However, limited by the quality of wireless link, the uploading of sensed data has an upper frequency. To reduce upload frequency, most of the existing WBAN data collection approaches collect data with a tolerable error. These approaches can guarantee precision of the collected data, but they are not able to ensure that the upload frequency is within the upper frequency. Some traditional sampling based approaches can control upload frequency directly, however, they usually have a high loss of information. Since the core task of WBAN applications is to collect health information, this paper aims to collect optimized information under the limitation of upload frequency. The importance of sensed data is defined according to information theory for the first time. Information-aware adaptive sampling is proposed to collect uniformly distributed data. Then we propose Adaptive Sampling-based Information Collection (ASIC) which consists of two algorithms. An adaptive sampling probability algorithm is proposed to compute sampling probabilities of different sensed values. A multiple uniform sampling algorithm provides uniform samplings for values in different intervals. Experiments based on a real dataset show that the proposed approach has higher performance in terms of data coverage and information quantity. The parameter analysis shows the optimized parameter settings and the discussion shows the underlying reason of high performance in the proposed approach.

  11. Adaptive Sampling-Based Information Collection for Wireless Body Area Networks

    PubMed Central

    Xu, Xiaobin; Zhao, Fang; Wang, Wendong; Tian, Hui

    2016-01-01

    To collect important health information, WBAN applications typically sense data at a high frequency. However, limited by the quality of wireless link, the uploading of sensed data has an upper frequency. To reduce upload frequency, most of the existing WBAN data collection approaches collect data with a tolerable error. These approaches can guarantee precision of the collected data, but they are not able to ensure that the upload frequency is within the upper frequency. Some traditional sampling based approaches can control upload frequency directly, however, they usually have a high loss of information. Since the core task of WBAN applications is to collect health information, this paper aims to collect optimized information under the limitation of upload frequency. The importance of sensed data is defined according to information theory for the first time. Information-aware adaptive sampling is proposed to collect uniformly distributed data. Then we propose Adaptive Sampling-based Information Collection (ASIC) which consists of two algorithms. An adaptive sampling probability algorithm is proposed to compute sampling probabilities of different sensed values. A multiple uniform sampling algorithm provides uniform samplings for values in different intervals. Experiments based on a real dataset show that the proposed approach has higher performance in terms of data coverage and information quantity. The parameter analysis shows the optimized parameter settings and the discussion shows the underlying reason of high performance in the proposed approach. PMID:27589758

  12. Propeller pitch change mechanism

    SciTech Connect

    Hora, P.

    1992-10-13

    This patent describes an aircraft propulsion system. It comprises: a first turbine carrying a first set of propeller blades; a second turbine carrying a second set of propeller blades; a gear system carried by the first turbine for changing pitch of the first set of propeller blades, which includes a pair of ring gears, both coaxial with the first turbine; a first set of planet gears which engage both ring gears and which induce pitch change when the planet gears rotate; a sun gear which drives the planet gears; a second set of planet gears which are carried by a planet gear carrier affixed to the second turbine and which drive the sun gear in order to change pitch by causing relative motion between the sung ear and the first turbine; and means for preventing a change in speed of the planet gear carrier from causing a change in pitch.

  13. An Adaptive Data Collection Algorithm Based on a Bayesian Compressed Sensing Framework

    PubMed Central

    Liu, Zhi; Zhang, Mengmeng; Cui, Jian

    2014-01-01

    For Wireless Sensor Networks, energy efficiency is always a key consideration in system design. Compressed sensing is a new theory which has promising prospects in WSNs. However, how to construct a sparse projection matrix is a problem. In this paper, based on a Bayesian compressed sensing framework, a new adaptive algorithm which can integrate routing and data collection is proposed. By introducing new target node selection metrics, embedding the routing structure and maximizing the differential entropy for each collection round, an adaptive projection vector is constructed. Simulations show that compared to reference algorithms, the proposed algorithm can decrease computation complexity and improve energy efficiency. PMID:24818659

  14. Collective Signal Processing in Cluster Chemotaxis: Roles of Adaptation, Amplification, and Co-attraction in Collective Guidance

    PubMed Central

    Camley, Brian A.; Zimmermann, Juliane; Levine, Herbert; Rappel, Wouter-Jan

    2016-01-01

    Single eukaryotic cells commonly sense and follow chemical gradients, performing chemotaxis. Recent experiments and theories, however, show that even when single cells do not chemotax, clusters of cells may, if their interactions are regulated by the chemoattractant. We study this general mechanism of “collective guidance” computationally with models that integrate stochastic dynamics for individual cells with biochemical reactions within the cells, and diffusion of chemical signals between the cells. We show that if clusters of cells use the well-known local excitation, global inhibition (LEGI) mechanism to sense chemoattractant gradients, the speed of the cell cluster becomes non-monotonic in the cluster’s size—clusters either larger or smaller than an optimal size will have lower speed. We argue that the cell cluster speed is a crucial readout of how the cluster processes chemotactic signals; both amplification and adaptation will alter the behavior of cluster speed as a function of size. We also show that, contrary to the assumptions of earlier theories, collective guidance does not require persistent cell-cell contacts and strong short range adhesion. If cell-cell adhesion is absent, and the cluster cohesion is instead provided by a co-attraction mechanism, e.g. chemotaxis toward a secreted molecule, collective guidance may still function. However, new behaviors, such as cluster rotation, may also appear in this case. Co-attraction and adaptation allow for collective guidance that is robust to varying chemoattractant concentrations while not requiring strong cell-cell adhesion. PMID:27367541

  15. 76 FR 61779 - Agency Information Collection (Application for Automobile or Other Conveyance and Adaptive...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-05

    ... AFFAIRS Agency Information Collection (Application for Automobile or Other Conveyance and Adaptive... refer to ``OMB Control No. 2900-0067.'' SUPPLEMENTARY INFORMATION: Title: Application for Automobile or..., servicepersons and their survivors complete VA Form 21-4502 to apply for automobile or other conveyance...

  16. Adaptation of Collective Moral Disengagement Scale into Turkish Culture for Adolescents

    ERIC Educational Resources Information Center

    Çapan, Bahtiyar Eraslan; Bakioglu, Fuad

    2016-01-01

    In this study, reliability and validity are assessed for a Turkish culture adaptation of the Collective Moral Disengagement Scale for Adolescents. The study was carried out in two stages. In the first stage, translation, exploratory factor analysis, internal consistency coefficients, and test-retest method were performed; in the second stage,…

  17. Adapting a Hospital Information System to Data Collection for Clinical Research

    PubMed Central

    Foy, John L.; Palestine, Alan G.; Nealon, Regina C.; Vincent, William D.; Nussenblatt, Robert B.; Lewis, Thomas L.

    1985-01-01

    A hospital-wide medical information system (MIS) has been adapted to serve as a specialized data collection vehicle for an outpatient clinical trial. The system provides structured data collection, automatic encoding of data elements (and some values), and entry of both fixed- and variable-length data. Collected items are automatically passed to a general-purpose computing facility for storage, manipulation, and analysis. Protocol data is entered directly by physicians and nurses at the time of patient contact, using MIS terminals and procedures already familiar to them by virtue of routine use for patient care. Protocol data is improved in accuracy, completeness, and timeliness, at very low marginal cost.

  18. PITCHING MECHANICS, REVISITED

    PubMed Central

    2013-01-01

    The overhead pitching motion is described as a coordinated sequence of body movements and muscular forces that have an ultimate goal of achieving high ball velocity and target accuracy. An understanding of the dynamic overhead throwing motion outlined in this clinical commentary can assist the clinician in addressing the unique injuries experienced by the pitcher. The potential biomechanical sources for injury have been studied utilizing videography and electromyographic techniques due to the rapid pace with which the pitching motion occurs. This clinical comentary will describe what is widely accepted as the six phases of the pitching motion and the relationship to the kinetic chain theory as well as outline the common mechanical faults that can lead to increased tissue stress and potential injury. Level of Evidence: 5 PMID:24175144

  19. Pitch carbon microsphere composite

    NASA Technical Reports Server (NTRS)

    Price, H. L.; Nelson, J. B.

    1977-01-01

    Petroleum pitch carbon microspheres were prepared by flash heating emulsified pitch and carbonizing the resulting microspheres in an inert atmosphere. Microsphere composites were obtained from a mixture of microspheres and tetraester precursor pyrrone powder. Scanning electron micrographs of the composite showed that it was an aggregate of microspheres bonded together by the pyrrone at the sphere contact points, with voids in and among the microspheres. Physical, thermal, and sorption properties of the composite are described. Composite applications could include use as a honeycomb filler in elevated-temperature load-bearing sandwich boards or in patient-treatment tables for radiation treatment of tumors.

  20. Low melting mesophase pitches

    SciTech Connect

    Diefendorf, R.J.; Chen, S.H.

    1984-04-17

    A low melting point, low molecular weight, heptane insoluble, 1,2,4-trichlorobenzene soluble mesophase pitch useful in carbon fiber spinning as such or as a plasticizer in a carbon fiber spinning composition is obtained by heating chrysene, triphenylene or paraterphenyl as well as mixtures thereof and hydrocarbon fractions containing the same, dissolving the resulting heat treated material with 1,2,4-trichlorobenzene, and separating the insolubles, and then contacting the 1,2,4-trichlorobenzene soluble fraction with a sufficient amount of heptane to precipitate the low melting point, low molecular weight mesophase pitch.

  1. Relationship Between the Medial Elbow Adduction Moment During Pitching and Ulnar Collateral Ligament Appearance During Magnetic Resonance Imaging Evaluation

    PubMed Central

    Hurd, Wendy J.; Kaufman, Kenton R.; Murthy, Naveen S.

    2014-01-01

    Background Medial elbow distraction during pitching as the primary mechanism contributing to adaptations in ulnar collateral ligament (UCL) appearance during magnetic resonance imaging (MRI) evaluation has not been established. Hypothesis Uninjured high school–aged pitchers with unilateral adaptations of the UCL exhibit a higher peak internal elbow adduction moment than those without UCL adaptations. Study Design Cohort study (Prevalence); Level of evidence, 2. Methods Twenty uninjured, asymptomatic high school–aged pitchers underwent bilateral elbow MRI examinations. Three-dimensional motion analysis testing was performed to collect throwing arm biomechanics as participants pitched from an indoor mound. Nonparametric tests were performed to compare peak internal elbow adduction moment in uninjured participants with and without adaptations in UCL appearance and to determine the nature of the relationship between the peak internal adduction moment and UCL appearance. Results Uninjured participants with UCL thickening exhibited a higher peak internal elbow adduction moment of 53.3 ± 6.8 N·m compared with uninjured participants without adaptations in UCL appearance, 38.8 ± 10.9 N·m (P = .05), as higher moments were correlated with ligament thickening (correlation coefficient, 0.45) (P = .02). Conclusion This study establishes the association between medial elbow distraction captured by the internal adduction moment during pitching and UCL adaptations visible during MRI evaluation. PMID:21335342

  2. Pitch features of environmental sounds

    NASA Astrophysics Data System (ADS)

    Yang, Ming; Kang, Jian

    2016-07-01

    A number of soundscape studies have suggested the need for suitable parameters for soundscape measurement, in addition to the conventional acoustic parameters. This paper explores the applicability of pitch features that are often used in music analysis and their algorithms to environmental sounds. Based on the existing alternative pitch algorithms for simulating the perception of the auditory system and simplified algorithms for practical applications in the areas of music and speech, the applicable algorithms have been determined, considering common types of sound in everyday soundscapes. Considering a number of pitch parameters, including pitch value, pitch strength, and percentage of audible pitches over time, different pitch characteristics of various environmental sounds have been shown. Among the four sound categories, i.e. water, wind, birdsongs, and urban sounds, generally speaking, both water and wind sounds have low pitch values and pitch strengths; birdsongs have high pitch values and pitch strengths; and urban sounds have low pitch values and a relatively wide range of pitch strengths.

  3. Vocal Pitch Shift in Congenital Amusia (Pitch Deafness)

    ERIC Educational Resources Information Center

    Hutchins, Sean; Peretz, Isabelle

    2013-01-01

    We tested whether congenital amusics, who exhibit pitch perception deficits, nevertheless adjust the pitch of their voice in response to a sudden pitch shift applied to vocal feedback. Nine amusics and matched controls imitated their own previously-recorded speech or singing, while the online feedback they received was shifted mid-utterance by 25…

  4. Fast automated protein NMR data collection and assignment by ADAPT-NMR on Bruker spectrometers

    NASA Astrophysics Data System (ADS)

    Lee, Woonghee; Hu, Kaifeng; Tonelli, Marco; Bahrami, Arash; Neuhardt, Elizabeth; Glass, Karen C.; Markley, John L.

    2013-11-01

    ADAPT-NMR (Assignment-directed Data collection Algorithm utilizing a Probabilistic Toolkit in NMR) supports automated NMR data collection and backbone and side chain assignment for [U-13C, U-15N]-labeled proteins. Given the sequence of the protein and data for the orthogonal 2D 1H-15N and 1H-13C planes, the algorithm automatically directs the collection of tilted plane data from a variety of triple-resonance experiments so as to follow an efficient pathway toward the probabilistic assignment of 1H, 13C, and 15N signals to specific atoms in the covalent structure of the protein. Data collection and assignment calculations continue until the addition of new data no longer improves the assignment score. ADAPT-NMR was first implemented on Varian (Agilent) spectrometers [A. Bahrami, M. Tonelli, S.C. Sahu, K.K. Singarapu, H.R. Eghbalnia, J.L. Markley, PLoS One 7 (2012) e33173]. Because of broader interest in the approach, we present here a version of ADAPT-NMR for Bruker spectrometers. We have developed two AU console programs (ADAPT_ORTHO_run and ADAPT_NMR_run) that run under TOPSPIN Versions 3.0 and higher. To illustrate the performance of the algorithm on a Bruker spectrometer, we tested one protein, chlorella ubiquitin (76 amino acid residues), that had been used with the Varian version: the Bruker and Varian versions achieved the same level of assignment completeness (98% in 20 h). As a more rigorous evaluation of the Bruker version, we tested a larger protein, BRPF1 bromodomain (114 amino acid residues), which yielded an automated assignment completeness of 86% in 55 h. Both experiments were carried out on a 500 MHz Bruker AVANCE III spectrometer equipped with a z-gradient 5 mm TCI probe. ADAPT-NMR is available at http://pine.nmrfam.wisc.edu/ADAPT-NMR in the form of pulse programs, the two AU programs, and instructions for installation and use.

  5. Fast automated protein NMR data collection and assignment by ADAPT-NMR on Bruker spectrometers.

    PubMed

    Lee, Woonghee; Hu, Kaifeng; Tonelli, Marco; Bahrami, Arash; Neuhardt, Elizabeth; Glass, Karen C; Markley, John L

    2013-11-01

    ADAPT-NMR (Assignment-directed Data collection Algorithm utilizing a Probabilistic Toolkit in NMR) supports automated NMR data collection and backbone and side chain assignment for [U-(13)C, U-(15)N]-labeled proteins. Given the sequence of the protein and data for the orthogonal 2D (1)H-(15)N and (1)H-(13)C planes, the algorithm automatically directs the collection of tilted plane data from a variety of triple-resonance experiments so as to follow an efficient pathway toward the probabilistic assignment of (1)H, (13)C, and (15)N signals to specific atoms in the covalent structure of the protein. Data collection and assignment calculations continue until the addition of new data no longer improves the assignment score. ADAPT-NMR was first implemented on Varian (Agilent) spectrometers [A. Bahrami, M. Tonelli, S.C. Sahu, K.K. Singarapu, H.R. Eghbalnia, J.L. Markley, PLoS One 7 (2012) e33173]. Because of broader interest in the approach, we present here a version of ADAPT-NMR for Bruker spectrometers. We have developed two AU console programs (ADAPT_ORTHO_run and ADAPT_NMR_run) that run under TOPSPIN Versions 3.0 and higher. To illustrate the performance of the algorithm on a Bruker spectrometer, we tested one protein, chlorella ubiquitin (76 amino acid residues), that had been used with the Varian version: the Bruker and Varian versions achieved the same level of assignment completeness (98% in 20 h). As a more rigorous evaluation of the Bruker version, we tested a larger protein, BRPF1 bromodomain (114 amino acid residues), which yielded an automated assignment completeness of 86% in 55 h. Both experiments were carried out on a 500 MHz Bruker AVANCE III spectrometer equipped with a z-gradient 5 mm TCI probe. ADAPT-NMR is available at http://pine.nmrfam.wisc.edu/ADAPT-NMR in the form of pulse programs, the two AU programs, and instructions for installation and use.

  6. Process for producing mesophase pitch

    SciTech Connect

    Shibatani, H.; Kameda, T.; Takahashi, K.

    1985-07-09

    Mesophase pitch containing quinoline soluble mesophase is produced from a pitch having a specific aromatic hydrogen content with a short heat treatment time without conducting any special treatment such as extraction.

  7. Pitch based foam with particulate

    DOEpatents

    Klett, James W.

    2001-01-01

    A thermally conductive, pitch based foam composite having a particulate content. The particulate alters the mechanical characteristics of the foam without severely degrading the foam thermal conductivity. The composite is formed by mixing the particulate with pitch prior to foaming.

  8. Adapt

    NASA Astrophysics Data System (ADS)

    Bargatze, L. F.

    2015-12-01

    Active Data Archive Product Tracking (ADAPT) is a collection of software routines that permits one to generate XML metadata files to describe and register data products in support of the NASA Heliophysics Virtual Observatory VxO effort. ADAPT is also a philosophy. The ADAPT concept is to use any and all available metadata associated with scientific data to produce XML metadata descriptions in a consistent, uniform, and organized fashion to provide blanket access to the full complement of data stored on a targeted data server. In this poster, we present an application of ADAPT to describe all of the data products that are stored by using the Common Data File (CDF) format served out by the CDAWEB and SPDF data servers hosted at the NASA Goddard Space Flight Center. These data servers are the primary repositories for NASA Heliophysics data. For this purpose, the ADAPT routines have been used to generate data resource descriptions by using an XML schema named Space Physics Archive, Search, and Extract (SPASE). SPASE is the designated standard for documenting Heliophysics data products, as adopted by the Heliophysics Data and Model Consortium. The set of SPASE XML resource descriptions produced by ADAPT includes high-level descriptions of numerical data products, display data products, or catalogs and also includes low-level "Granule" descriptions. A SPASE Granule is effectively a universal access metadata resource; a Granule associates an individual data file (e.g. a CDF file) with a "parent" high-level data resource description, assigns a resource identifier to the file, and lists the corresponding assess URL(s). The CDAWEB and SPDF file systems were queried to provide the input required by the ADAPT software to create an initial set of SPASE metadata resource descriptions. Then, the CDAWEB and SPDF data repositories were queried subsequently on a nightly basis and the CDF file lists were checked for any changes such as the occurrence of new, modified, or deleted

  9. Modified Adaptive Control for Region 3 Operation in the Presence of Wind Turbine Structural Modes

    NASA Technical Reports Server (NTRS)

    Frost, Susan Alane; Balas, Mark J.; Wright, Alan D.

    2010-01-01

    Many challenges exist for the operation of wind turbines in an efficient manner that is reliable and avoids component fatigue and failure. Turbines operate in highly turbulent environments resulting in aerodynamic loads that can easily excite turbine structural modes, possibly causing component fatigue and failure. Wind turbine manufacturers are highly motivated to reduce component fatigue and failure that can lead to loss of revenue due to turbine down time and maintenance costs. The trend in wind turbine design is toward larger, more flexible turbines that are ideally suited to adaptive control methods due to the complexity and expense required to create accurate models of their dynamic characteristics. In this paper, we design an adaptive collective pitch controller for a high-fidelity simulation of a utility-scale, variable-speed horizontal axis wind turbine operating in Region 3. The objective of the adaptive pitch controller is to regulate generator speed, accommodate wind gusts, and reduce the excitation of structural modes in the wind turbine. The control objective is accomplished by collectively pitching the turbine blades. The adaptive collective pitch controller for Region 3 was compared in simulations with a baseline classical Proportional Integrator (PI) collective pitch controller. The adaptive controller will demonstrate the ability to regulate generator speed in Region 3, while accommodating gusts, and reducing the excitation of certain structural modes in the wind turbine.

  10. Dual output variable pitch turbofan actuation system

    NASA Technical Reports Server (NTRS)

    Griswold, R. H., Jr.; Broman, C. L. (Inventor)

    1976-01-01

    An improved actuating mechanism was provided for a gas turbine engine incorporating fan blades of the variable pitch variety, the actuator adapted to rotate the individual fan blades within apertures in an associated fan disc. The actuator included means such as a pair of synchronizing ring gears, one on each side of the blade shanks, and adapted to engage pinions disposed thereon. Means were provided to impart rotation to the ring gears in opposite directions to effect rotation of the blade shanks in response to a predetermined input signal. In the event of system failure, a run-away actuator was prevented by an improved braking device which arrests the mechanism.

  11. Lower pitch is larger, yet falling pitches shrink.

    PubMed

    Eitan, Zohar; Schupak, Asi; Gotler, Alex; Marks, Lawrence E

    2014-01-01

    Experiments using diverse paradigms, including speeded discrimination, indicate that pitch and visually-perceived size interact perceptually, and that higher pitch is congruent with smaller size. While nearly all of these studies used static stimuli, here we examine the interaction of dynamic pitch and dynamic size, using Garner's speeded discrimination paradigm. Experiment 1 examined the interaction of continuous rise/fall in pitch and increase/decrease in object size. Experiment 2 examined the interaction of static pitch and size (steady high/low pitches and large/small visual objects), using an identical procedure. Results indicate that static and dynamic auditory and visual stimuli interact in opposite ways. While for static stimuli (Experiment 2), higher pitch is congruent with smaller size (as suggested by earlier work), for dynamic stimuli (Experiment 1), ascending pitch is congruent with growing size, and descending pitch with shrinking size. In addition, while static stimuli (Experiment 2) exhibit both congruence and Garner effects, dynamic stimuli (Experiment 1) present congruence effects without Garner interference, a pattern that is not consistent with prevalent interpretations of Garner's paradigm. Our interpretation of these results focuses on effects of within-trial changes on processing in dynamic tasks and on the association of changes in apparent size with implied changes in distance. Results suggest that static and dynamic stimuli can differ substantially in their cross-modal mappings, and may rely on different processing mechanisms.

  12. Spiral model of pitch

    NASA Astrophysics Data System (ADS)

    Miller, James D.

    2003-10-01

    A spiral model of pitch interrelates tone chroma, tone height, equal temperament scales, and a cochlear map. Donkin suggested in 1870 that the pitch of tones could be well represented by an equiangular spiral. More recently, the cylindrical helix has been popular for representing tone chroma and tone height. Here it is shown that tone chroma, tone height, and cochlear position can be conveniently related to tone frequency via a planar spiral. For this ``equal-temperament spiral,'' (ET Spiral) tone chroma is conceived as a circular array with semitones at 30° intervals. The frequency of sound on the cent scale (re 16.351 Hz) is represented by the radius of the spiral defined by r=(1200/2π)θr, where θr is in radians. By these definitions, one revolution represents one octave, 1200 cents, 30° represents a semitone, the radius relates θ to cents in accordance with equal temperament (ET) tuning, and the arclength of the spiral matches the mapping of sound frequency to the basilar membrane. Thus, the ET Spiral gives tone chroma as θ, tone height as the cent scale, and the cochlear map as the arclength. The possible implications and directions for further work are discussed.

  13. Process for producing mesophase pitch

    SciTech Connect

    Izumi, T.; Igarashi, S.; Naito, T.

    1985-08-06

    A substantially uniform mesophase pitch is prepared by treating a mesophase forming pitch material at elevated temperatures above about 380/sup 0/ C. to produce a mixture of mesophase and non-mesophase pitch containing about 20% to about 80% mesophase. The mixture is then maintained at a temperature below about 400/sup 0/ C. for a time sufficient to allow the mesophase to coalesce and settle as a lower separable layer. A mesophase pitch so produced may contain from 90 to 100% mesophase with a softening point of less than 320/sup 0/ C.

  14. Vortex Dynamics around Pitching Plates

    DTIC Science & Technology

    2014-04-29

    wing . The strong tip vortices that develop while the wing pitches induce large downward velocity that pushes the LEV towards the centerline of the...Fluids 52, 441–462 (2012). 20 23J. D. Eldredge, C. Wang, and M. V. Ol, “A computational study of a canonical pitch - up , pitch -down wing maneuver,” (39th...AIAA Fluid Dynamics Conference (AIAA2009-3687), 2009). 24T. O. Yilmaz and D. Rockwell, “Flow structure on finite-span wings due to pitch - up motion,” J

  15. Optical Communication System for Remote Monitoring and Adaptive Control of Distributed Ground Sensors Exhibiting Collective Intelligence

    SciTech Connect

    Cameron, S.M.; Stantz, K.M.; Trahan, M.W.; Wagner, J.S.

    1998-11-01

    Comprehensive management of the battle-space has created new requirements in information management, communication, and interoperability as they effect surveillance and situational awareness. The objective of this proposal is to expand intelligent controls theory to produce a uniquely powerful implementation of distributed ground-based measurement incorporating both local collective behavior, and interoperative global optimization for sensor fusion and mission oversight. By using a layered hierarchal control architecture to orchestrate adaptive reconfiguration of autonomous robotic agents, we can improve overall robustness and functionality in dynamic tactical environments without information bottlenecks. In this concept, each sensor is equipped with a miniaturized optical reflectance modulator which is interactively monitored as a remote transponder using a covert laser communication protocol from a remote mothership or operative. Robot data-sharing at the ground level can be leveraged with global evaluation criteria, including terrain overlays and remote imaging data. Information sharing and distributed intelli- gence opens up a new class of remote-sensing applications in which small single-function autono- mous observers at the local level can collectively optimize and measure large scale ground-level signals. AS the need for coverage and the number of agents grows to improve spatial resolution, cooperative behavior orchestrated by a global situational awareness umbrella will be an essential ingredient to offset increasing bandwidth requirements within the net. A system of the type described in this proposal will be capable of sensitively detecting, tracking, and mapping spatial distributions of measurement signatures which are non-stationary or obscured by clutter and inter- fering obstacles by virtue of adaptive reconfiguration. This methodology could be used, for example, to field an adaptive ground-penetrating radar for detection of underground structures in

  16. Lower extremity muscle activation during baseball pitching.

    PubMed

    Campbell, Brian M; Stodden, David F; Nixon, Megan K

    2010-04-01

    The purpose of this study was to investigate muscle activation levels of select lower extremity muscles during the pitching motion. Bilateral surface electromyography data on 5 lower extremity muscles (biceps femoris, rectus femoris, gluteus maximus, vastus medialis, and gastrocnemius) were collected on 11 highly skilled baseball pitchers and compared with individual maximal voluntary isometric contraction (MVIC) data. The pitching motion was divided into 4 distinct phases: phase 1, initiation of pitching motion to maximum stride leg knee height; phase 2, maximum stride leg knee height to stride foot contact (SFC); phase 3, SFC to ball release; and phase 4, ball release to 0.5 seconds after ball release (follow-through). Results indicated that trail leg musculature elicited moderate to high activity levels during phases 2 and 3 (38-172% of MVIC). Muscle activity levels of the stride leg were moderate to high during phases 2-4 (23-170% of MVIC). These data indicate a high demand for lower extremity strength and endurance. Specifically, coaches should incorporate unilateral and bilateral lower extremity exercises for strength improvement or maintenance and to facilitate dynamic stabilization of the lower extremities during the pitching motion.

  17. Augmented Adaptive Control of a Wind Turbine in the Presence of Structural Modes

    NASA Technical Reports Server (NTRS)

    Frost, Susan A.; Balas, Mark J.; Wright, Alan D.

    2010-01-01

    Wind turbines operate in highly turbulent environments resulting in aerodynamic loads that can easily excite turbine structural modes, potentially causing component fatigue and failure. Two key technology drivers for turbine manufacturers are increasing turbine up time and reducing maintenance costs. Since the trend in wind turbine design is towards larger, more flexible turbines with lower frequency structural modes, manufacturers will want to develop methods to operate in the presence of these modes. Accurate models of the dynamic characteristics of new wind turbines are often not available due to the complexity and expense of the modeling task, making wind turbines ideally suited to adaptive control. In this paper, we develop theory for adaptive control with rejection of disturbances in the presence of modes that inhibit the controller. We use this method to design an adaptive collective pitch controller for a high-fidelity simulation of a utility-scale, variable-speed wind turbine operating in Region 3. The objective of the adaptive pitch controller is to regulate generator speed, accommodate wind gusts, and reduce the interference of certain structural modes in feedback. The control objective is accomplished by collectively pitching the turbine blades. The adaptive pitch controller for Region 3 is compared in simulations with a baseline classical Proportional Integrator (PI) collective pitch controller.

  18. Does Fatigue Alter Pitching Mechanics?

    PubMed Central

    Chalmers, Peter Nissen; Erickson, Brandon J.; Sgroi, Terrance; Vignona, Peter; Lesniak, Matthew; Bush-Joseph, Charles A.; Verma, Nikhil N.; Romeo, Anthony A.

    2016-01-01

    Objectives: Background: Injuries of the adolescent shoulder and elbow are common in baseball pitchers. Fatigue has been demonstrated to be a risk factor for injury. Purpose: To determine if shoulder and elbow kinematics, pitching velocity, accuracy, and pain change during a simulated full baseball game in adolescent pitchers. Methods: Methods: Adolescent pitchers between the ages of 13-16 were recruited to throw a 90 pitch simulated game. Shoulder range of motion was assessed before and after the game. Velocity and accuracy were measured for every pitch and every 15th pitch was videotaped from two orthogonal views in high definition at 240 Hz. Quantitative and qualitative mechanics were measured from these videos. Perceived fatigue and pain were assessed after each inning using the visual analog scale. Data was statistically analyzed using a repeated-measures analysis of variance. Results: Results: Twenty-eight elite adolescent pitchers were included. These pitchers, on average, were 14.6±0.9 years old (mean ± standard deviation), had been pitching for 6.3±1.7 years, and threw 94±58 pitches per week. Our experimental model functioned as expected in that pitchers became progressively more fatigued and painful and pitched with a lower velocity as pitch number increased (p<0.001, 0.001, and <0.001 respectively). Knee flexion at ball release progressively increased with pitch number (p=0.008). Hip and shoulder separation significantly decreased as pitch number increased, from 90%±40% at pitch 15 to 40%±50% at pitch 90 (p0.271 in all cases, 91% power for elbow flexion at ball release). External rotation and total range of motion in the pitching shoulder significantly increased post-pitching (p=0.007 and 0.047 respectively). Conclusion: Conclusion: As pitchers progress through a simulated game they throw lower velocity pitches and become fatigued and painful. Core and leg musculature becomes fatigued before upper extremity kinematics change. Based upon these

  19. Fast pitch softball injuries.

    PubMed

    Meyers, M C; Brown, B R; Bloom, J A

    2001-01-01

    The popularity of fast pitch softball in the US and throughout the world is well documented. Along with this popularity, there has been a concomitant increase in the number of injuries. Nearly 52% of cases qualify as major disabling injuries requiring 3 weeks or more of treatment and 2% require surgery. Interestingly, 75% of injuries occur during away games and approximately 31% of traumas occur during nonpositional and conditioning drills. Injuries range from contusions and tendinitis to ligamentous disorders and fractures. Although head and neck traumas account for 4 to 12% of cases, upper extremity traumas account for 23 to 47% of all injuries and up to 19% of cases involve the knee. Approximately 34 to 42% of injuries occur when the athlete collides with another individual or object. Other factors involved include the quality of playing surface, athlete's age and experience level, and the excessive physical demands associated with the sport. Nearly 24% of injuries involve base running and are due to poor judgement, sliding technique, current stationary base design, unorthodox joint and extremity position during ground impact and catching of cleats. The increasing prevalence of overtraining syndrome among athletes has been attributed to an unclear definition of an optimal training zone, poor communication between player and coach, and the limited ability of bone and connective tissue to quickly respond to match the demands of the sport. This has led routinely to arm, shoulder and lumbar instability, chronic nonsteroidal anti-inflammatory drug (NSAID) use and time loss injuries in 45% of pitching staff during a single season. Specific attention to a safer playing environment, coaching and player education, and sport-specific training and conditioning would reduce the risk, rate and severity of fast pitch traumas. Padding of walls, backstops, rails and dugout areas, as well as minimising use of indoor facilities, is suggested to decrease the number of collision

  20. Thresholds for Shifting Visually Perceived Eye Level Due to Incremental Pitches

    NASA Technical Reports Server (NTRS)

    Scott, Donald M.; Welch, Robert; Cohen, M. M.; Hill, Cyndi

    2001-01-01

    Visually perceived eye level (VPEL) was judged by subjects as they viewed a luminous grid pattern that was pitched by 2 or 5 deg increments between -20 deg and +20 deg. Subjects were dark adapted for 20 min and indicated--VPEL by directing the beam of a laser pointer to the rear wall of a 1.25 m cubic pitch box that rotated about a horizontal axis midpoint on the rear wall. Data were analyzed by ANOVA and the Tukey HSD procedure. Results showed a 10.0 deg threshold for pitches P(sub i) above the reference pitch P(sub 0), and a -10.3 deg threshold for pitches P(sub i) below-the reference-pitch P(sub 0). Threshold data for pitches P(sub i) < P(sub 0) suggest an asymmetric threshold for VPEL below and above physical eye level.

  1. Adaptive free energy sampling in multidimensional collective variable space using boxed molecular dynamics.

    PubMed

    O'Connor, Mike; Paci, Emanuele; McIntosh-Smith, Simon; Glowacki, David R

    2016-12-22

    The past decade has seen the development of a new class of rare event methods in which molecular configuration space is divided into a set of boundaries/interfaces, and then short trajectories are run between boundaries. For all these methods, an important concern is how to generate boundaries. In this paper, we outline an algorithm for adaptively generating boundaries along a free energy surface in multi-dimensional collective variable (CV) space, building on the boxed molecular dynamics (BXD) rare event algorithm. BXD is a simple technique for accelerating the simulation of rare events and free energy sampling which has proven useful for calculating kinetics and free energy profiles in reactive and non-reactive molecular dynamics (MD) simulations across a range of systems, in both NVT and NVE ensembles. Two key developments outlined in this paper make it possible to automate BXD, and to adaptively map free energy and kinetics in complex systems. First, we have generalized BXD to multidimensional CV space. Using strategies from rigid-body dynamics, we have derived a simple and general velocity-reflection procedure that conserves energy for arbitrary collective variable definitions in multiple dimensions, and show that it is straightforward to apply BXD to sampling in multidimensional CV space so long as the Cartesian gradients ∇CV are available. Second, we have modified BXD to undertake on-the-fly statistical analysis during a trajectory, harnessing the information content latent in the dynamics to automatically determine boundary locations. Such automation not only makes BXD considerably easier to use; it also guarantees optimal boundaries, speeding up convergence. We have tested the multidimensional adaptive BXD procedure by calculating the potential of mean force for a chemical reaction recently investigated using both experimental and computational approaches - i.e., F + CD3CN → DF + D2CN in both the gas phase and a strongly coupled explicit CD3CN solvent

  2. Macaque Monkeys Discriminate Pitch Relationships

    ERIC Educational Resources Information Center

    Brosch, Michael; Selezneva, Elena; Bucks, Cornelia; Scheich, Henning

    2004-01-01

    This study demonstrates that non-human primates can categorize the direction of the pitch change of tones in a sequence. Two "Macaca fascicularis" were trained in a positive-reinforcement behavioral paradigm in which they listened to sequences of a variable number of different acoustic items. The training of discriminating pitch direction was…

  3. Adaptation of rabbit cortical collecting duct HCO3- transport to metabolic acidosis in vitro.

    PubMed Central

    Tsuruoka, S; Schwartz, G J

    1996-01-01

    Net HCO3- transport in the rabbit kidney cortical collecting duct (CCD) is mediated by simultaneous H+ secretion and HCO3- secretion, most likely occurring in a alpha- and beta-intercalated cells (ICs), respectively. The polarity of net HCO3- transport is shifted from secretion to absorption after metabolic acidosis or acid incubation of the CCD. We investigated this adaptation by measuring net HCO3- flux before and after incubating CCDs 1 h at pH 6.8 followed by 2 h at pH 7.4. Acid incubation always reversed HCO3- flux from net secretion to absorption, whereas incubation for 3 h at pH 7.4 did not. Inhibition of alpha-IC function (bath CL- removal or DIDS, luminal bafilomycin) stimulated net HCO3- secretion by approximately 2 pmol/min per mm before acid incubation, whereas after incubation these agents inhibited net HCO3- absorption by approximately 5 pmol/min per mm. Inhibition of beta-IC function (luminal Cl- removal) inhibited HCO3- secretion by approximately 9 pmol/min per mm before incubation, whereas after incubation HCO3- absorption by only 3 pmol/min per mm. After acid incubation, luminal SCH28080 inhibited HCO3- absorption by only 5-15% vs the circa 90% inhibitory effect of bafilomycin. In outer CCDs, which contain fewer alpha-ICs than midcortical segments, the reversal in polarity of HCO3- flux was blunted after acid incubation. We conclude that the CCD adapts to low pH in vitro by downregulation HCO3- secretion in beta-ICs via decreased apical CL-/base exchang activity and upregulating HCO3- absorption in alpha-ICs via increased apical H+ -ATPase and basolateral CL-/base exchange activities. Whether or not there is a reversal of IC polarity or recruitment of gamma-ICs in this adaptation remains to be established. PMID:8613531

  4. An adaptive scheduling model for a multi-agent based VEPR data collection actions.

    PubMed

    Vieira-Marques, Pedro; Jácome, Jorge; Hilário-Patriarca, José; Cruz-Correia, Ricardo

    2015-01-01

    With the purpose of improving the access to departmental legacy information systems, a multi agent based Virtual Electronic Patient Record (VEPR) was deployed at a major Portuguese Hospital. The agent module (MAID) is in charge of identifying new data produced (reports), collecting and making it available through an integrated web interface. The deployed MAID system uses a static interval for checking the existence of new data, however from the gathered data regarding each department data production it is observable a variable rate throughout the day. In order to address this variability an adaptive model was developed and tested in a simulated environment with real data. The model takes in consideration the past report production profiles for determining a variable query frequency in order to reduce the average time to make data available minimizing the number of departmental requests.

  5. Dichotomy and perceptual distortions in absolute pitch ability

    PubMed Central

    Athos, E. Alexandra; Levinson, Barbara; Kistler, Amy; Zemansky, Jason; Bostrom, Alan; Freimer, Nelson; Gitschier, Jane

    2007-01-01

    Absolute pitch (AP) is the rare ability to identify the pitch of a tone without the aid of a reference tone. Understanding both the nature and genesis of AP can provide insights into neuroplasticity in the auditory system. We explored factors that may influence the accuracy of pitch perception in AP subjects both during the development of the trait and in later age. We used a Web-based survey and a pitch-labeling test to collect perceptual data from 2,213 individuals, 981 (44%) of whom proved to have extraordinary pitch-naming ability. The bimodal distribution in pitch-naming ability signifies AP as a distinct perceptual trait, with possible implications for its genetic basis. The wealth of these data has allowed us to uncover unsuspected note-naming irregularities suggestive of a “perceptual magnet” centered at the note “A.” In addition, we document a gradual decline in pitch-naming accuracy with age, characterized by a perceptual shift in the “sharp” direction. These findings speak both to the process of acquisition of AP and to its stability. PMID:17724340

  6. Dichotomy and perceptual distortions in absolute pitch ability.

    PubMed

    Athos, E Alexandra; Levinson, Barbara; Kistler, Amy; Zemansky, Jason; Bostrom, Alan; Freimer, Nelson; Gitschier, Jane

    2007-09-11

    Absolute pitch (AP) is the rare ability to identify the pitch of a tone without the aid of a reference tone. Understanding both the nature and genesis of AP can provide insights into neuroplasticity in the auditory system. We explored factors that may influence the accuracy of pitch perception in AP subjects both during the development of the trait and in later age. We used a Web-based survey and a pitch-labeling test to collect perceptual data from 2,213 individuals, 981 (44%) of whom proved to have extraordinary pitch-naming ability. The bimodal distribution in pitch-naming ability signifies AP as a distinct perceptual trait, with possible implications for its genetic basis. The wealth of these data has allowed us to uncover unsuspected note-naming irregularities suggestive of a "perceptual magnet" centered at the note "A." In addition, we document a gradual decline in pitch-naming accuracy with age, characterized by a perceptual shift in the "sharp" direction. These findings speak both to the process of acquisition of AP and to its stability.

  7. Thermal stability of petroleum pitches

    SciTech Connect

    Sorensen, I.W.

    1982-01-01

    Petroleum pitches and similar materials are becoming increasingly important as raw materials for the production of various types of carbons and graphites. Most recently, significant interest in such materials as low cost precursors for carbon fiber has developed. Crucial to success in this regard is the behavior of pitches and related substances as they pass through a mesophase or liquid crystalline form during heat treatment to form carbonaceous material. There is limited understanding of this phenomenon as well as the effects of pitch modification on it. An effort was made to elucidate the mesophase formation mechanisms by comparison of thermally-formed mesophase with that formed more rapidly in solvent-separated narrower pitch fractions. Specifically, selected pitches are subjected to heat treatment and characterized in terms of their composition, microstructural development, and rheology. Independent study was made of the effects of shearing field on composition, mesophase development, and molecular weight distributions for CTP-240 pitch. Complementary work is described for the thermal decomposition of pitch fractions obtained by solvent extraction. Several important technical advances are described that will assist in further study of these materials.

  8. Do ferrets perceive relative pitch?

    PubMed

    Yin, Pingbo; Fritz, Jonathan B; Shamma, Shihab A

    2010-03-01

    The existence of relative pitch perception in animals is difficult to demonstrate, since unlike humans, animals often attend to absolute rather than relative properties of sound elements. However, the results of the present study show that ferrets can be trained using relative pitch to discriminate two-tone sequences (rising vs. falling). Three ferrets were trained using a positive-reinforcement paradigm in which sequences of reference (one to five repeats) and target stimuli were presented, and animals were rewarded only when responding correctly to the target. The training procedure consisted of three training phases that successively shaped the ferrets to attend to relative pitch. In Phase-1 training, animals learned the basic task with sequences of invariant tone-pairs and could use absolute pitch information. During Phase-2 training, in order to emphasize relative cues, absolute pitch was varied each trial within a two-octave frequency range. In Phase-3 training, absolute pitch cues were removed, and only relative cue information was available to solve the task. Two ferrets successfully completed training on all three phases and achieved significant discriminative performance over the trained four-octave frequency range. These results suggest that ferrets can be trained to discern the relative pitch relationship of a sequence of tone-pairs independent of frequency.

  9. Method for producing mesophase pitch

    SciTech Connect

    Watarabe, M.

    1985-07-16

    A method for producing a 100% mesophase pitch composed only of Q.I. and Q.S. components is provided. This method comprises subjecting petroleum-origin pitch to heat treatment with stirring under a stream of a hydrocarbon gas of small carbon atom numbers at atmospheric or superatmospheric pressure, holding said heat-treated pitch in quiescent state to melt and coalesce only the mesophase therein and dividing and separating non-mesophase and mesophase layers. Resulting 100% mesophase enables us to produce high strength, high modulus carbon fibers.

  10. Method for producing mesophase pitch

    SciTech Connect

    Watanale, M.

    1985-07-16

    A method for producing a 100% mesophase composed only of Q.I. component and Q.S. component is provived. This method comprises forming mesophase by the heat treatment of petroleum-origin pitch, subjecting the heat-formed pitch to a condition of heating under quiescent state to cause only the mesophase in the heat-formed pitch to grow and coalesce, separating only the non-mesophase of the upper layer and repeating the operation of the heat treatment and maintenance of heating under a quiescent state by the separated non-mesophase, as a raw material.

  11. Silicon modeling of pitch perception.

    PubMed Central

    Lazzaro, J; Mead, C

    1989-01-01

    We have designed and tested an integrated circuit that models human pitch perception. The chip receives as input a time-varying voltage corresponding to sound pressure at the ear and produces as output a map of perceived pitch. The chip is a physiological model; subcircuits on the chip correspond to known and proposed structures in the auditory system. Chip output approximates human performance in response to a variety of classical pitch-perception stimuli. The 125,000-transistor chip computes all outputs in real time by using analog continuous-time processing. PMID:2594787

  12. Electro-acoustic stimulation. Acoustic and electric pitch comparisons.

    PubMed

    McDermott, Hugh; Sucher, Catherine; Simpson, Andrea

    2009-01-01

    For simultaneous acoustic and electric stimulation to be perceived as complementary, it may be beneficial for hearing aids and cochlear implants (CI) to be adjusted to provide compatible pitch sensations. To this end, estimates of the pitch perceived for a set of acoustic and electric stimuli were obtained from 14 CI users who had usable low-frequency hearing, either in the non-implanted ear or in both ears. The subjects assigned numerical pitch estimates to each of 5 acoustic pure tones and 5 single-electrode electric pulse trains. On average, the acoustic frequency that corresponded in pitch to stimulation on the most apical electrode was approximately 480 Hz. This was about 1 octave lower than the frequency expected from Greenwood's frequency-place function applied to estimates of the electrode insertion angle based on X-ray images. Furthermore, evidence was found suggesting that pitch decreased with increasing duration of CI use. Pitch estimates from 5 subjects who completed the experiment before experiencing any other sounds through their CI were generally close to the values expected from a recently published frequency map for the cochlear spiral ganglion. Taken together, these findings suggest that some perceptual adaptation may occur that would compensate in part for the apparent mismatch between the intracochlear position of the electrodes and the acoustic frequencies assigned to them in the sound processor.

  13. Beethoven's Last Piano Sonata and Those Who Follow Crocodiles: Cross-Domain Mappings of Auditory Pitch in a Musical Context

    ERIC Educational Resources Information Center

    Eitan, Zohar; Timmers, Renee

    2010-01-01

    Though auditory pitch is customarily mapped in Western cultures onto spatial verticality (high-low), both anthropological reports and cognitive studies suggest that pitch may be mapped onto a wide variety of other domains. We collected a total number of 35 pitch mappings and investigated in four experiments how these mappings are used and…

  14. STS-135: Rendezvous Pitch Maneuver

    NASA Video Gallery

    On July 10, 2011, space shuttle Atlantis performed the nine-minute Rendezvous Pitch Maneuver, or “backflip.” With Commander Chris Ferguson at the helm, Atlantis rotated 360 degrees backward to ...

  15. STS-133: Rendezvous Pitch Maneuver

    NASA Video Gallery

    At 1:15 p.m. EST Saturday, space shuttle Discovery began the nine-minute Rendezvous Pitch Maneuver, or "backflip." With Commander Steve Lindsey at the helm, Discovery rotated 360 degrees backward t...

  16. Adaptation.

    PubMed

    Broom, Donald M

    2006-01-01

    The term adaptation is used in biology in three different ways. It may refer to changes which occur at the cell and organ level, or at the individual level, or at the level of gene action and evolutionary processes. Adaptation by cells, especially nerve cells helps in: communication within the body, the distinguishing of stimuli, the avoidance of overload and the conservation of energy. The time course and complexity of these mechanisms varies. Adaptive characters of organisms, including adaptive behaviours, increase fitness so this adaptation is evolutionary. The major part of this paper concerns adaptation by individuals and its relationships to welfare. In complex animals, feed forward control is widely used. Individuals predict problems and adapt by acting before the environmental effect is substantial. Much of adaptation involves brain control and animals have a set of needs, located in the brain and acting largely via motivational mechanisms, to regulate life. Needs may be for resources but are also for actions and stimuli which are part of the mechanism which has evolved to obtain the resources. Hence pigs do not just need food but need to be able to carry out actions like rooting in earth or manipulating materials which are part of foraging behaviour. The welfare of an individual is its state as regards its attempts to cope with its environment. This state includes various adaptive mechanisms including feelings and those which cope with disease. The part of welfare which is concerned with coping with pathology is health. Disease, which implies some significant effect of pathology, always results in poor welfare. Welfare varies over a range from very good, when adaptation is effective and there are feelings of pleasure or contentment, to very poor. A key point concerning the concept of individual adaptation in relation to welfare is that welfare may be good or poor while adaptation is occurring. Some adaptation is very easy and energetically cheap and

  17. Adapting federated cyberinfrastructure for shared data collection facilities in structural biology

    PubMed Central

    Stokes-Rees, Ian; Levesque, Ian; Murphy, Frank V.; Yang, Wei; Deacon, Ashley; Sliz, Piotr

    2012-01-01

    Early stage experimental data in structural biology is generally unmaintained and inaccessible to the public. It is increasingly believed that this data, which forms the basis for each macromolecular structure discovered by this field, must be archived and, in due course, published. Furthermore, the widespread use of shared scientific facilities such as synchrotron beamlines complicates the issue of data storage, access and movement, as does the increase of remote users. This work describes a prototype system that adapts existing federated cyberinfra­structure technology and techniques to significantly improve the operational environment for users and administrators of synchrotron data collection facilities used in structural biology. This is achieved through software from the Virtual Data Toolkit and Globus, bringing together federated users and facilities from the Stanford Synchrotron Radiation Lightsource, the Advanced Photon Source, the Open Science Grid, the SBGrid Consortium and Harvard Medical School. The performance and experience with the prototype provide a model for data management at shared scientific facilities. PMID:22514186

  18. Pitch perfect: how fruit flies control their body pitch angle.

    PubMed

    Whitehead, Samuel C; Beatus, Tsevi; Canale, Luca; Cohen, Itai

    2015-11-01

    Flapping insect flight is a complex and beautiful phenomenon that relies on fast, active control mechanisms to counter aerodynamic instability. To directly investigate how freely flying Drosophila melanogaster control their body pitch angle against such instability, we perturbed them using impulsive mechanical torques and filmed their corrective maneuvers with high-speed video. Combining experimental observations and numerical simulation, we found that flies correct for pitch deflections of up to 40 deg in 29±8 ms by bilaterally modulating their wings' front-most stroke angle in a manner well described by a linear proportional-integral (PI) controller. Flies initiate this corrective process only 10±2 ms after the perturbation onset, indicating that pitch stabilization involves a fast reflex response. Remarkably, flies can also correct for very large-amplitude pitch perturbations--greater than 150 deg--providing a regime in which to probe the limits of the linear-response framework. Together with previous studies regarding yaw and roll control, our results on pitch show that flies' stabilization of each of these body angles is consistent with PI control.

  19. Pitch canker disease of pines.

    PubMed

    Gordon, T R

    2006-06-01

    ABSTRACT Pitch canker, caused by Fusarium circinatum, is a disease affecting pines in many locations throughout the world. The pathosystem was originally described in the southeastern (SE) United States and was identified in California in 1986. Limited vegetative compatibility group (VCG) diversity in the California population of F. circinatum, relative to the SE United States, suggests the former is a recently established and clonally propagating population. Although the much greater VCG diversity found in the SE United States is suggestive of out-crossing, molecular markers indicate that many vegetatively incompatible isolates are clonally related. This implies that VCG diversity may derive, at least in part, from somatic mutations rather than sexual reproduction. Pitch canker is damaging to many pine species and one at particular risk is Monterey pine (Pinus radiata), which is widely grown in plantations and is highly susceptible to pitch canker. However, some Monterey pines are resistant to pitch canker and some severely diseased trees have been observed to recover. The absence of new infections on these trees reflects the operation of systemic induced resistance, apparently in response to repeated infection by the pitch canker pathogen.

  20. Knowledge-based pitch detection

    NASA Astrophysics Data System (ADS)

    Dove, W. P.

    1986-06-01

    Many problems in signal processing involve a mixture of numerical and symbolic knowledge. Examples of problems of this sort include the recognition of speech and the analysis of images. This thesis focuses on the problem of employing a mixture of symbolic and numerical knowledge within a single system, through the development of a system directed at a modified pitch detection problem. For this thesis, the conventional pitch detection problem was modified by providing a phonetic transcript and sex/age information as input to the system, in addition to the acoustic waveform. The Pitch Detector's Assistant (PDA) system that was developed is an interactive facility for evaluating ways of approaching this problem. The PDA system allows the user to interrupt processing at any point, change either input data, derived data, or problem knowledge and continue execution.

  1. Process for producing mesophase pitch

    SciTech Connect

    Isumi, T.; Naito, T.; Igarashi, S.

    1988-11-29

    This patient describes process for producing a mesophase pitch having a mesophase content of above 90% and a softening point of below 320/sup 0/ C. comprising the steps of: heat-treating a pitch forming material at elevated temperatures above about 380/sup 0/C for a time sufficient to provide a mixture of mesophase and non-mesophase pitch containing about 20% to about 80% (by weight) of mesophase and a softening point of no greater than 250/sup 0/C; aging and settling the mesophase portion of the mixture of mesophase and non-mesophase pitch obtained in step by maintaining the mixture in a substantially quiescent condition and at a temperature below the temperature in the heat-treating step, at which temperature the mixture is sufficiently liquid so that the separation of the mesophase and non-mesophase portions of the mixture can be substantially accomplished, (and above about 350/sup 0/C) for a time sufficient for the mesophase portion of the mixture to coalesce and accumulate into a substantially lower homogeneous mesophase pitch layer containing at least 90% mesophase and an upper layer comprising the non-mesophase portion of the mixture; and separating the lower mesophase layer from the upper non-mesophase layer whereby a mesophase pitch which has a mesopphase content of above 90% and a softening point below 320/sup 0/C is obtained. heat-treated at a temperature in the range of about 380/sup 0/C to about 460/sup 0/C whereby thermal cracking and polycondensation reaction occur.

  2. A collection of Australian Drosophila datasets on climate adaptation and species distributions

    PubMed Central

    Hangartner, Sandra B.; Hoffmann, Ary A.; Smith, Ailie; Griffin, Philippa C.

    2015-01-01

    The Australian Drosophila Ecology and Evolution Resource (ADEER) collates Australian datasets on drosophilid flies, which are aimed at investigating questions around climate adaptation, species distribution limits and population genetics. Australian drosophilid species are diverse in climatic tolerance, geographic distribution and behaviour. Many species are restricted to the tropics, a few are temperate specialists, and some have broad distributions across climatic regions. Whereas some species show adaptability to climate changes through genetic and plastic changes, other species have limited adaptive capacity. This knowledge has been used to identify traits and genetic polymorphisms involved in climate change adaptation and build predictive models of responses to climate change. ADEER brings together 103 datasets from 39 studies published between 1982–2013 in a single online resource. All datasets can be downloaded freely in full, along with maps and other visualisations. These historical datasets are preserved for future studies, which will be especially useful for assessing climate-related changes over time. PMID:26601886

  3. Adaptive Control Using Residual Mode Filters Applied to Wind Turbines

    NASA Technical Reports Server (NTRS)

    Frost, Susan A.; Balas, Mark J.

    2011-01-01

    Many dynamic systems containing a large number of modes can benefit from adaptive control techniques, which are well suited to applications that have unknown parameters and poorly known operating conditions. In this paper, we focus on a model reference direct adaptive control approach that has been extended to handle adaptive rejection of persistent disturbances. We extend this adaptive control theory to accommodate problematic modal subsystems of a plant that inhibit the adaptive controller by causing the open-loop plant to be non-minimum phase. We will augment the adaptive controller using a Residual Mode Filter (RMF) to compensate for problematic modal subsystems, thereby allowing the system to satisfy the requirements for the adaptive controller to have guaranteed convergence and bounded gains. We apply these theoretical results to design an adaptive collective pitch controller for a high-fidelity simulation of a utility-scale, variable-speed wind turbine that has minimum phase zeros.

  4. Ball Speed and Release Consistency Predict Pitching Success in Major League Baseball.

    PubMed

    Whiteside, David; Martini, Douglas N; Zernicke, Ronald F; Goulet, Grant C

    2016-07-01

    Whiteside, D, Martini, DN, Zernicke, RF, and Goulet, GC. Ball speed and release consistency predict pitching success in Major League Baseball. J Strength Cond Res XX(X): 000-000, 2015-This study aimed to quantify how ball flight kinematics (i.e., ball speed and movement), release location, and variations therein relate to pitching success in Major League Baseball (MLB). One hundred ninety starting MLB pitchers met the inclusion criteria for this study. Ball trajectory information was collected for 76,000 pitches and inserted into a forward stepwise multiple regression model, which examined how (a) pitch selection, (b) ball speed, (c) ball movement (horizontal and lateral), (d) release location (horizontal and lateral), (e) variation in pitch speed, (f) variation in ball movement, and (g) variation in release location related to pitching success (as measured by fielding independent pitching-FIP). Pitch speed, release location variability, variation in pitch speed, and horizontal release location were significant predictors of FIP and, collectively, accounted for 24% of the variance in FIP. These findings suggest that (a) maximizing ball speed, (b) refining a consistent spatial release location, and (c) using varied pitch speeds should be primary foci for the pitching coach. However, between-pitcher variations underline how training interventions should be administered at the individual level, with consideration given to the pitcher's injury history. Finally, despite offering significant predictors of success, these three factors explained only 22% of the variance in FIP and should not be considered the only, or preeminent, indicators of a pitcher's effectiveness. Evidently, traditional pitching metrics only partly account for a pitcher's effectiveness, and future research is necessary to uncover the remaining contributors to success.

  5. Propeller/fan-pitch feathering apparatus

    NASA Technical Reports Server (NTRS)

    Schilling, Jan C. (Inventor); Adamson, Arthur P. (Inventor); Bathori, Julius (Inventor); Walker, Neil (Inventor)

    1990-01-01

    A pitch feathering system for a gas turbine driven aircraft propeller having multiple variable pitch blades utilizes a counter-weight linked to the blades. The weight is constrained to move, when effecting a pitch change, only in a radial plane and about an axis which rotates about the propeller axis. The system includes a linkage allowing the weight to move through a larger angle than the associated pitch change of the blade.

  6. Method of casting pitch based foam

    DOEpatents

    Klett, James W.

    2002-01-01

    A process for producing molded pitch based foam is disclosed which minimizes cracking. The process includes forming a viscous pitch foam in a container, and then transferring the viscous pitch foam from the container into a mold. The viscous pitch foam in the mold is hardened to provide a carbon foam having a relatively uniform distribution of pore sizes and a highly aligned graphic structure in the struts.

  7. Pitch perception prior to cortical maturation

    NASA Astrophysics Data System (ADS)

    Lau, Bonnie K.

    Pitch perception plays an important role in many complex auditory tasks including speech perception, music perception, and sound source segregation. Because of the protracted and extensive development of the human auditory cortex, pitch perception might be expected to mature, at least over the first few months of life. This dissertation investigates complex pitch perception in 3-month-olds, 7-month-olds and adults -- time points when the organization of the auditory pathway is distinctly different. Using an observer-based psychophysical procedure, a series of four studies were conducted to determine whether infants (1) discriminate the pitch of harmonic complex tones, (2) discriminate the pitch of unresolved harmonics, (3) discriminate the pitch of missing fundamental melodies, and (4) have comparable sensitivity to pitch and spectral changes as adult listeners. The stimuli used in these studies were harmonic complex tones, with energy missing at the fundamental frequency. Infants at both three and seven months of age discriminated the pitch of missing fundamental complexes composed of resolved and unresolved harmonics as well as missing fundamental melodies, demonstrating perception of complex pitch by three months of age. More surprisingly, infants in both age groups had lower pitch and spectral discrimination thresholds than adult listeners. Furthermore, no differences in performance on any of the tasks presented were observed between infants at three and seven months of age. These results suggest that subcortical processing is not only sufficient to support pitch perception prior to cortical maturation, but provides adult-like sensitivity to pitch by three months.

  8. Music Lessons, Pitch Processing, and "g"

    ERIC Educational Resources Information Center

    Schellenberg, E. Glenn; Moreno, Sylvain

    2010-01-01

    Musically trained and untrained participants were administered tests of pitch processing and general intelligence ("g"). Trained participants exhibited superior performance on tests of pitch-processing speed and relative pitch. They were also better at frequency discrimination with tones at 400 Hz but not with very high tones (4000 Hz). The two…

  9. Cross-Cultural Perspectives on Pitch Memory

    ERIC Educational Resources Information Center

    Trehub, Sandra E.; Schellenberg, E. Glenn; Nakata, Takayuki

    2008-01-01

    We examined effects of age and culture on children's memory for the pitch level of familiar music. Canadian 9- and 10-year-olds distinguished the original pitch level of familiar television theme songs from foils that were pitch-shifted by one semitone, whereas 5- to 8-year-olds failed to do so (Experiment 1). In contrast, Japanese 5- and…

  10. Spirality: Spiral arm pitch angle measurement

    NASA Astrophysics Data System (ADS)

    Shields, Douglas W.; Boe, Benjamin; Pfountz, Casey; Davis, Benjamin L.; Hartley, Matthew; Pour Imani, Hamed; Slade, Zac; Kennefick, Daniel; Kennefick, Julia

    2015-12-01

    Spirality measures spiral arm pitch angles by fitting galaxy images to spiral templates of known pitch. Written in MATLAB, the code package also includes GenSpiral, which produces FITS images of synthetic spirals, and SpiralArmCount, which uses a one-dimensional Fast Fourier Transform to count the spiral arms of a galaxy after its pitch is determined.

  11. Dynamics of fluidic devices with applications to rotor pitch links

    NASA Astrophysics Data System (ADS)

    Scarborough, Lloyd H., III

    impedance. At low frequency, the pitch link must have high impedance to pass through the pilot's collective and cyclic commands to control the aircraft. At higher frequencies, however, the pitch-link impedance can be tuned to change the blade pitching response to higher harmonic loads. Active blade control to produce higher harmonic pitch motions has been shown to reduce hub loads and increase rotor efficiency. This work investigates whether fluidic pitch links can passively provide these benefits. An analytical model of a fluidic pitch link is derived and incorporated into a rotor aeroelastic simulation for a rotor similar to that of the UH-60. Eighty-one simulations with varied fluidic pitch link parameters demonstrate that their impedance can be tailored to reduce rotor power and all six hub forces and moments. While no impedance was found that simultaneously reduced all components, the results include cases with reductions in the lateral 4/rev hub force of up to 91% and 4/rev hub pitching moment of up to 67%, and main rotor power of up to 5%.

  12. Pitch and Plasticity: Insights from the Pitch Matching of Chords by Musicians with Absolute and Relative Pitch

    PubMed Central

    McLachlan, Neil M.; Marco, David J. T.; Wilson, Sarah J.

    2013-01-01

    Absolute pitch (AP) is a form of sound recognition in which musical note names are associated with discrete musical pitch categories. The accuracy of pitch matching by non-AP musicians for chords has recently been shown to depend on stimulus familiarity, pointing to a role of spectral recognition mechanisms in the early stages of pitch processing. Here we show that pitch matching accuracy by AP musicians was also dependent on their familiarity with the chord stimulus. This suggests that the pitch matching abilities of both AP and non-AP musicians for concurrently presented pitches are dependent on initial recognition of the chord. The dual mechanism model of pitch perception previously proposed by the authors suggests that spectral processing associated with sound recognition primes waveform processing to extract stimulus periodicity and refine pitch perception. The findings presented in this paper are consistent with the dual mechanism model of pitch, and in the case of AP musicians, the formation of nominal pitch categories based on both spectral and periodicity information. PMID:24961624

  13. Collective Fluctuations in the Dynamics of Adaptation and Other Traveling Waves

    PubMed Central

    Hallatschek, Oskar; Geyrhofer, Lukas

    2016-01-01

    The dynamics of adaptation are difficult to predict because it is highly stochastic even in large populations. The uncertainty emerges from random genetic drift arising in a vanguard of particularly fit individuals of the population. Several approaches have been developed to analyze the crucial role of genetic drift on the expected dynamics of adaptation, including the mean fitness of the entire population, or the fate of newly arising beneficial deleterious mutations. However, little is known about how genetic drift causes fluctuations to emerge on the population level, where it becomes palpable as variations in the adaptation speed and the fitness distribution. Yet these phenomena control the decay of genetic diversity and variability in evolution experiments and are key to a truly predictive understanding of evolutionary processes. Here, we show that correlations induced by these emergent fluctuations can be computed at any arbitrary order by a suitable choice of a dynamical constraint. The resulting linear equations exhibit fluctuation-induced terms that amplify short-distance correlations and suppress long-distance ones. These terms, which are in general not small, control the decay of genetic diversity and, for wave-tip dominated (“pulled”) waves, lead to anticorrelations between the tip of the wave and the lagging bulk of the population. While it is natural to consider the process of adaptation as a branching random walk in fitness space subject to a constraint (due to finite resources), we show that other traveling wave phenomena in ecology and evolution likewise fall into this class of constrained branching random walks. Our methods, therefore, provide a systematic approach toward analyzing fluctuations in a wide range of population biological processes, such as adaptation, genetic meltdown, species invasions, or epidemics. PMID:26819246

  14. Comparison of individual pitch and smart rotor control strategies for load reduction

    NASA Astrophysics Data System (ADS)

    Plumley, C.; Leithead, W.; Jamieson, P.; Bossanyi, E.; Graham, M.

    2014-06-01

    Load reduction is increasingly seen as an essential part of controller and wind turbine design. On large multi-MW wind turbines that experience high levels of wind shear and turbulence across the rotor, individual pitch control and smart rotor control are being considered. While individual pitch control involves adjusting the pitch of each blade individually to reduce the cyclic loadings on the rotor, smart rotor control involves activating control devices distributed along the blades to alter the local aerodynamics of the blades. Here we investigate the effectiveness of using a DQ-axis control and a distributed (independent) control for both individual pitch and trailing edge flap smart rotor control. While load reductions are similar amongst the four strategies across a wide range of variables, including blade root bending moments, yaw bearing and shaft, the pitch actuator requirements vary. The smart rotor pitch actuator has reduced travel, rates, accelerations and power requirements than that of the individual pitch controlled wind turbines. This benefit alone however would be hard to justify the added design complexities of using a smart rotor, which can be seen as an alternative to upgrading the pitch actuator and bearing. In addition, it is found that the independent control strategy is apt at roles that the collective pitch usually targets, such as tower motion and speed control, and it is perhaps here, in supplementing other systems, that the future of the smart rotor lies.

  15. Structural Load Analysis of a Wind Turbine under Pitch Actuator and Controller Faults

    NASA Astrophysics Data System (ADS)

    Etemaddar, Mahmoud; Gao, Zhen; Moan, Torgeir

    2014-12-01

    In this paper, we investigate the characteristics of a wind turbine under blade pitch angle and shaft speed sensor faults as well as pitch actuator faults. A land-based NREL 5MW variable speed pitch reg- ulated wind turbine is considered as a reference. The conventional collective blade pitch angle controller strategy with independent pitch actuators control is used for load reduction. The wind turbine class is IEC-BII. The main purpose is to investigate the severity of end effects on structural loads and responses and consequently identify the high-risk components according to the type and amplitude of fault using a servo-aero-elastic simulation code, HAWC2. Both transient and steady state effects of faults are studied. Such information is useful for wind turbine fault detection and identification as well as system reliability analysis. Results show the effects of faults on wind turbine power output and responses. Pitch sensor faults mainly affects the vibration of shaft main bearing, while generator power and aerodynamic thrust are not changed significantly, due to independent pitch actuator control of three blades. Shaft speed sensor faults can seriously affect the generator power and aerodynamic thrust. Pitch actuator faults can result in fully pitching of the blade, and consequently rotor stops due to negative aerodynamic torque.

  16. Toward a quantitative account of pitch distribution in spontaneous narrative: Method and validation

    PubMed Central

    Matteson, Samuel E.; Streit Olness, Gloria; Caplow, Nancy J.

    2013-01-01

    Pitch is well-known both to animate human discourse and to convey meaning in communication. The study of the statistical population distributions of pitch in discourse will undoubtedly benefit from methodological improvements. The current investigation examines a method that parameterizes pitch in discourse as musical pitch interval H measured in units of cents and that disaggregates the sequence of peak word-pitches using tools employed in time-series analysis and digital signal processing. The investigators test the proposed methodology by its application to distributions in pitch interval of the peak word-pitch (collectively called the discourse gamut) that occur in simulated and actual spontaneous emotive narratives obtained from 17 middle-aged African-American adults. The analysis, in rigorous tests, not only faithfully reproduced simulated distributions imbedded in realistic time series that drift and include pitch breaks, but the protocol also reveals that the empirical distributions exhibit a common hidden structure when normalized to a slowly varying mode (called the gamut root) of their respective probability density functions. Quantitative differences between narratives reveal the speakers' relative propensity for the use of pitch levels corresponding to elevated degrees of a discourse gamut (the “e-la”) superimposed upon a continuum that conforms systematically to an asymmetric Laplace distribution. PMID:23654400

  17. Carbon fibers from SRC pitch

    DOEpatents

    Greskovich, Eugene J.; Givens, Edwin N.

    1981-01-01

    This invention relates to an improved method of manufacturing carbon fibers from a coal derived pitch. The improvement resides in the use of a solvent refined coal which has been hydrotreated and subjected to solvent extraction whereby the hetero atom content in the resulting product is less than 4.0% by weight and the softening point is between about 100.degree.-250.degree. F.

  18. Rehabilitation of the pitching shoulder.

    PubMed

    Pappas, A M; Zawacki, R M; McCarthy, C F

    1985-01-01

    Shoulder pain is a common complaint among baseball pitchers. Frequently, the nature of shoulder pathology can be traced to lack of flexibility and muscular imbalance. This paper describes: the normal biomechanics of a properly functioning shoulder during a baseball pitch, pathomechanics of shoulder problems, flexibility requirements of the throwing shoulder, and the muscular balance necessary for an effective throwing shoulder. Appropriate examination procedures are described along with remedial exercises which ensure normal glenohumeral motion and integrated muscle action.

  19. Yaw sensory rearrangement alters pitch vestibulo-ocular reflex responses

    NASA Technical Reports Server (NTRS)

    Petropoulos, A. E.; Wall, C. 3rd; Oman, C. M.

    1997-01-01

    Ten male subjects underwent two types of adaptation paradigm designed either to enhance or to attenuate the gain of the canal-ocular reflex (COR), before undergoing otolith-ocular reflex (OOR) testing with constant velocity, earth horizontal axis and pitch rotation. The adaptation paradigm paired a 0.2 Hz sinusoidal rotation about an earth vertical axis with a 0.2 Hz optokinetic stimulus that was deliberately mismatched in peak velocity or phase and was designed to produce short-term changes in the COR. Preadaptation and postadaptation OOR tests occurred at a constant velocity of 60 degrees/sec in the dark and produced a modulation component of the slow phase velocity with a frequency of 0.16 Hz due to otolithic stimulation by the sinusoidally changing gravity vector. Of the seven subjects who showed enhancement of the COR gain, six also showed enhancement of the OOR modulation component. Of the seven subjects who showed attenuation of the COR gain, five also showed attenuation of the OOR modulation component. The probability that these two cross-axis adaptation effects would occur by chance is less than 0.02. This suggests that visual-vestibular conditioning of the yaw axis COR also induced changes in the pitch axis OOR. We thus postulate that the central nervous system pathways that process horizontal canal yaw stimuli have elements in common with those processing otolithic stimuli about the pitch axis.

  20. Relations of pitch matching, pitch discrimination, and otoacoustic emission suppression in individuals not formally trained as musicians.

    PubMed

    Moore, Robert E; Estis, Julie M; Zhang, Fawen; Watts, Christopher; Marble, Elizabeth

    2007-06-01

    Research has yielded a relationship between pitch matching and pitch discrimination. Good pitch matchers tend to be good pitch discriminators and are often judged to be vocally talented. Otoacoustic emission suppression measures the function of the efferent auditory system which may affect accuracy for pitch matching and pitch discrimination. Formally trained musicians show pitch matching and pitch discrimination superior to those of nonmusicians and have greater efferent otoacoustic emission suppression than nonmusicians. This study investigated the relationship among pitch matching, pitch discrimination, and otoacoustic emission suppression in individuals with no formal musical training and who showed varied pitch matching and pitch discrimination. Analysis suggested a significant relationship between pitch matching and pitch discrimination but not between otoacoustic emission suppression and pitch matching and pitch discrimination. Findings are presented in the context of previous research indicating a significant relationship between otoacoustic emission suppression and musical talent in trained musicians.

  1. The musical environment and auditory plasticity: hearing the pitch of percussion.

    PubMed

    McLachlan, Neil M; Marco, David J T; Wilson, Sarah J

    2013-01-01

    Although musical skills clearly improve with training, pitch processing has generally been believed to be biologically determined by the behavior of brain stem neural mechanisms. Two main classes of pitch models have emerged over the last 50 years. Harmonic template models have been used to explain cross-channel integration of frequency information, and waveform periodicity models have been used to explain pitch discrimination that is much finer than the resolution of the auditory nerve. It has been proposed that harmonic templates are learnt from repeated exposure to voice, and so it may also be possible to learn inharmonic templates from repeated exposure to inharmonic music instruments. This study investigated whether pitch-matching accuracy for inharmonic percussion instruments was better in people who have trained on these instruments and could reliably recognize their timbre. We found that adults who had trained with Indonesian gamelan instruments were better at recognizing and pitch-matching gamelan instruments than people with similar levels of music training, but no prior exposure to these instruments. These findings suggest that gamelan musicians were able to use inharmonic templates to support accurate pitch processing for these instruments. We suggest that recognition mechanisms based on spectrotemporal patterns of afferent auditory excitation in the early stages of pitch processing allow rapid priming of the lowest frequency partial of inharmonic timbres, explaining how music training can adapt pitch processing to different musical genres and instruments.

  2. Aerodynamic control with passively pitching wings

    NASA Astrophysics Data System (ADS)

    Gravish, Nick; Wood, Robert

    Flapping wings may pitch passively under aerodynamic and inertial loads. Such passive pitching is observed in flapping wing insect and robot flight. The effect of passive wing pitch on the control dynamics of flapping wing flight are unexplored. Here we demonstrate in simulation and experiment the critical role wing pitching plays in yaw control of a flapping wing robot. We study yaw torque generation by a flapping wing allowed to passively rotate in the pitch axis through a rotational spring. Yaw torque is generated through alternating fast and slow upstroke and and downstroke. Yaw torque sensitively depends on both the rotational spring force law and spring stiffness, and at a critical spring stiffness a bifurcation in the yaw torque control relationship occurs. Simulation and experiment reveal the dynamics of this bifurcation and demonstrate that anomalous yaw torque from passively pitching wings is the result of aerodynamic and inertial coupling between the pitching and stroke-plane dynamics.

  3. Tone-language speakers show hemispheric specialization and differential cortical processing of contour and interval cues for pitch.

    PubMed

    Bidelman, G M; Chung, W-L

    2015-10-01

    Electrophysiological studies demonstrate that the neural coding of pitch is modulated by language experience and the linguistic relevance of the auditory input; both rightward and leftward asymmetries have been observed in the hemispheric specialization for pitch. In music, pitch is encoded using two primary features: contour (patterns of rises and falls) and interval (frequency separation between tones) cues. Recent evoked potential studies demonstrate that these "global" (contour) and "local" (interval) aspects of pitch are processed automatically (but bilaterally) in trained musicians. Here, we examined whether alternate forms of pitch expertise, namely, tone-language experience (i.e., Chinese), influence the early detection of contour and intervallic deviations within ongoing pitch sequences. Neuroelectric mismatch negativity (MMN) potentials were recorded in Chinese speakers and English-speaking nonmusicians in response to continuous pitch sequences with occasional global or local deviations in the ongoing melodic stream. This paradigm allowed us to explore potential cross-language differences in the hemispheric weighting for contour and interval processing of pitch. Chinese speakers showed differential pitch encoding between hemispheres not observed in English listeners; Chinese MMNs revealed a rightward bias for contour processing but a leftward hemispheric laterality for interval processing. In contrast, no asymmetries were observed in the English group. Collectively, our findings suggest tone-language experience sensitizes auditory brain mechanisms for the detection of subtle global/local pitch changes in the ongoing auditory stream and exaggerates functional asymmetries in pitch processing between cerebral hemispheres.

  4. Adaptation-induced collective dynamics of a single-cell protozoan

    NASA Astrophysics Data System (ADS)

    Ogata, Maiko; Hondou, Tsuyoshi; Hayakawa, Yoshinori; Hayashi, Yoshikatsu; Sugawara, Ken

    2008-01-01

    We investigate the behavior of a single-cell protozoan in a narrow tubular ring. This environment forces them to swim under a one-dimensional periodic boundary condition. Above a critical density, single-cell protozoa aggregate spontaneously without external stimulation. The high-density zone of swimming cells exhibits a characteristic collective dynamics including translation and boundary fluctuation. We analyzed the velocity distribution and turn rate of swimming cells and found that the regulation of the turing rate leads to a stable aggregation and that acceleration of velocity triggers instability of aggregation. These two opposing effects may help to explain the spontaneous dynamics of collective behavior. We also propose a stochastic model for the mechanism underlying the collective behavior of swimming cells.

  5. The Role of Collective Action in Enhancing Communities’ Adaptive Capacity to Environmental Risk: An Exploration of Two Case Studies from Asia

    PubMed Central

    Ireland, Philip; Thomalla, Frank

    2011-01-01

    Background In this paper we examine the role of collective action in assisting rural communities to cope with and adapt to environmental risks in Nepalgunj, Nepal and Krabi Province, Thailand. Drawing upon two case studies, we explore the role of collective action in building adaptive capacity, paying particular attention to the role of social networks. Methods Data for this paper was gathered using a range of different methods across the two different studies. In Nepal semi-structured interviews were conducted with a range of stakeholders in addition to participant observation and secondary data collection. In Thailand the researchers utilised a vulnerability assessment, participatory multi-stakeholder assessment, a detailed case study and an online dialogue. Findings We make three key observations: firstly, collective action plays a significant role in enhancing adaptive capacity and hence should be more strongly considered in the development of climate change adaptation strategies; secondly, social networks are a particularly important component of collective action for the building of adaptive capacity; and thirdly, the mandate, capacity, and structure of local government agencies can influence the effectiveness of collective action, both positively and negatively. Conclusions We argue that there is an urgent need for further consideration of the different forms of collective action within community-based disaster risk management and climate change adaptation. PMID:22045442

  6. Pitch Angle Survey of GOODS Spiral Galaxies

    NASA Astrophysics Data System (ADS)

    Boe, Benjamin; Kennefick, Daniel; Arkansas Galaxy Evolution Survey, Arkansas CenterSpace; Planetary Sciences

    2015-01-01

    This research looks at how the pitch angles of galaxies change over scales of cosmic time. We measure the pitch angle, or tightness of spiral winding, using a new code, Spirality. We then compare the results to those obtained from established software, 2DFFT (2 Dimensional Fast Fourier Transform). We investigate any correlation between pitch angle and redshift, or distance from Earth. Previous research indicates that the pitch angle of a galaxy correlates with its central bulge mass and the mass of its central black hole. Thus any evolution in the distribution of pitch angles could ultimately prove to be indicative of evolution in the supermassive black hole mass function. Galaxies from the Hubble GOODS (Great Observatories Origins Deep Survey) North and South were measured. We found that there was strong agreement between Spirality and 2DFFT measurements. Spirality measured the pitch angle of the GOODS galaxies with a lower error than 2DFFT on average. With both software a correlation between pitch angle and redshift was found. Spirality observed a 6.150 increase in pitch per unit redshift. The increase in pitch angle with redshift suggests that in the past galaxies had higher pitch angles, which could be indicative of lower central black hole masses (or, more directly, central bulge masses).

  7. Toward Collective Impact for Climate Resilience: Maximizing Climate Change Education for Preparedness, Adaptation, and Mitigation

    NASA Astrophysics Data System (ADS)

    Ledley, T. S.; Niepold, F., III; McCaffrey, M.

    2014-12-01

    Increasing the capacity of society to make informed climate decisions based on scientific evidence is imperative. While a wide range of education programs and communication efforts to improve understanding and facilitate responsible effective decision-making have been developed in recent years, these efforts have been largely disconnected. The interdisciplinary and trans-disciplinary nature of the problems and potential responses to climate change requires a broad range of expertise and a strategy that overcomes the inherent limitations of isolated programs and efforts. To extend the reach and impact of climate change education and engagement efforts, it is necessary to have a coordination that results in greater collective impact. The Collective Impact model, as described by Kania & Kramer (2011), requires five elements: 1) a common agenda; 2) shared measurement systems; 3) mutually reinforcing activities; 4) continuous communication; and 5) a well-funded backbone support organization. The CLEAN Network has facilitated a series of discussions at six professional meetings from late 2012 through spring 2014 to begin to develop and define the elements of collective impact on climate change education and engagement. These discussions have focused on getting input from the community on a common agenda and what a backbone support organization could do to help extend their reach and impact and enable a longer-term sustainability. These discussions will continue at future meetings, with the focus shifting to developing a common agenda and shared metrics. In this presentation we will summarize the outcomes of these discussions thus far, especially with respect to what activities a backbone support organization might provide to help increase the collective impact of climate change education effort and invite others to join the development of public-private partnership to improve the nations climate literacy. The cumulative input into this evolving discussion on collective

  8. Genetic Diversity and Population Structure in a Legacy Collection of Spring Barley Landraces Adapted to a Wide Range of Climates

    PubMed Central

    Walther, Alexander; Özkan, Hakan; Graner, Andreas; Kilian, Benjamin

    2014-01-01

    Global environmental change and increasing human population emphasize the urgent need for higher yielding and better adapted crop plants. One strategy to achieve this aim is to exploit the wealth of so called landraces of crop species, representing diverse traditional domesticated populations of locally adapted genotypes. In this study, we investigated a comprehensive set of 1485 spring barley landraces (Lrc1485) adapted to a wide range of climates, which were selected from one of the largest genebanks worldwide. The landraces originated from 5° to 62.5° N and 16° to 71° E. The whole collection was genotyped using 42 SSR markers to assess the genetic diversity and population structure. With an average allelic richness of 5.74 and 372 alleles, Lrc1485 harbours considerably more genetic diversity than the most polymorphic current GWAS panel for barley. Ten major clusters defined most of the population structure based on geographical origin, row type of the ear and caryopsis type – and were assigned to specific climate zones. The legacy core reference set Lrc648 established in this study will provide a long-lasting resource and a very valuable tool for the scientific community. Lrc648 is best suited for multi-environmental field testing to identify candidate genes underlying quantitative traits but also for allele mining approaches. PMID:25541702

  9. Nozzle designs with pitch precursor ablatives

    NASA Technical Reports Server (NTRS)

    Blevins, H. R.; Bedard, R. J.

    1976-01-01

    Recent developments in carbon phenolic ablatives for solid rocket motor nozzles have yielded a pitch precursor carbon fiber offering significant raw material availability and cost saving advantages as compared to conventional rayon precursor material. This paper discusses the results of an experimental program conducted to assess the thermal performance and characterize the thermal properties of pitch precursor carbon phenolic ablatives. The end result of this program is the complete thermal characterization of pitch fabric, pitch mat, hybrid pitch/rayon fabric and pitch mat molding compound. With these properties determined an analytic capability now exists for predicting the thermal performance of these materials in rocket nozzle liner applications. Further planned efforts to verify material performance and analytical prediction procedures through actual rocket motor firings are also discussed.

  10. The role of timbre in pitch matching abilities and pitch discrimination abilities with complex tones

    NASA Astrophysics Data System (ADS)

    Moore, Robert E.; Watts, Christopher R.; Zhang, Fawen

    2001-05-01

    Control of fundamental frequency (F0) is important for singing in-tune and is an important factor related to the perception of a talented singing voice. One purpose of the present study was to investigate the relationship between pitch-matching skills, which is one method of testing F0 control, and pitch discrimination skills. It was observed that there was a relationship between pitch matching abilities and pitch discrimination abilities. Those subjects that were accurate pitch matchers were also accurate pitch discriminators (and vice versa). Further, timbre differences appeared to play a role in pitch discrimination accuracy. A second part of the study investigated the effect of timbre on speech discrimination. To study this, all but the first five harmonics of complex tones with different timbre were removed for the pitch discrimination task, thus making the tones more similar in timbre. Under this condition no difference was found between the pitch discrimination abilities of those who were accurate pitch matchers and those who were inaccurate pitch matchers. The results suggest that accurate F0 control is at least partially dependent on pitch discrimination abilities, and timbre appears to play an important role in differences in pitch discrimination ability.

  11. Difficulties with Pitch Discrimination Influences Pitch Memory Performance: Evidence from Congenital Amusia

    PubMed Central

    Jiang, Cunmei; Lim, Vanessa K.; Wang, Hang; Hamm, Jeff P.

    2013-01-01

    Music processing is influenced by pitch perception and memory. Additionally these features interact, with pitch memory performance decreasing as the perceived distance between two pitches decreases. This study examined whether or not the difficulty of pitch discrimination influences pitch retention by testing individuals with congenital amusia. Pitch discrimination difficulty was equated by determining an individual’s threshold with a two down one up staircase procedure and using this to create conditions where two pitches (the standard and the comparison tones) differed by 1x, 2x, and 3x the threshold setting. For comparison with the literature a condition that employed a constant pitch difference of four semitones was also included. The results showed that pitch memory performance improved as the discrimination between the standard and the comparison tones was made easier for both amusic and control groups, and more importantly, that amusics did not show any pitch retention deficits when the discrimination difficulty was equated. In contrast, consistent with previous literature, amusics performed worse than controls when the physical pitch distance was held constant at four semitones. This impaired performance has been interpreted as evidence for pitch memory impairment in the past. However, employing a constant pitch distance always makes the difference closer to the discrimination threshold for the amusic group than for the control group. Therefore, reduced performance in this condition may simply reflect differences in the perceptual difficulty of the discrimination. The findings indicate the importance of equating the discrimination difficulty when investigating memory. PMID:24205375

  12. Local Cochlear Correlations of Perceived Pitch

    NASA Astrophysics Data System (ADS)

    Martignoli, Stefan; Stoop, Ruedi

    2010-07-01

    Pitch is one of the most salient attributes of the human perception of sound, but is still not well understood. This difficulty originates in the entwined nature of the phenomenon, in which a physical stimulus as well as a psychophysiological signal receiver are involved. In an electronic realization of a biophysically detailed nonlinear model of the cochlea, we find local cochlear correlates of the perceived pitch that explain all essential pitch-shifting phenomena from physical grounds.

  13. Perceptual interactions between musical pitch and timbre.

    PubMed

    Krumhansl, C L; Iverson, P

    1992-08-01

    These experiments examined perceptual interactions between musical pitch and timbre. Experiment 1, through the use of the Garner classification tasks, found that pitch and timbre of isolated tones interact. Classification times showed interference from uncorrelated variation in the irrelevant attribute and facilitation from correlated variation; the effects were symmetrical. Experiments 2 and 3 examined how musical pitch and timbre function in longer sequences. In recognition memory tasks, a target tone always appeared in a fixed position in the sequences, and listeners were instructed to attend to either its pitch or its timbre. For successive tones, no interactions between timbre and pitch were found. That is, changing the pitches of context tones did not affect timbre recognition, and vice versa. The tendency to perceive pitch in relation to other context pitches was strong and unaffected by whether timbre was constant or varying. In contrast, the relative perception of timbre was weak and was found only when pitch was constant. These results suggest that timbre is perceived more in absolute than in relative terms. Perceptual implications for creating patterns in music with timbre variations are discussed.

  14. Comparison of Two Independent LIDAR-Based Pitch Control Designs

    SciTech Connect

    Dunne, F.; Schlipf, D.; Pao, L. Y.

    2012-08-01

    Two different lidar-based feedforward controllers have previously been designed for the NREL 5 MW wind turbine model under separate studies. Feedforward controller A uses a finite-impulse-response design, with 5 seconds of preview, and three rotating lidar measurements. Feedforward controller B uses a static-gain design, with the preview time defined by the pitch actuator dynamics, a simulation of a real nacelle-based scanning lidar system, and a lowpass filter defined by the lidar configuration. These controllers are now directly compared under the same lidar configuration, in terms of fatigue load reduction, rotor speed regulation, and power capture. The various differences in design choices are discussed and compared. We also compare frequency plots of individual pitch feedforward and collective pitch feedforward load reductions, and we see that individual pitch feedforward is effective mainly at the once-per-revolution and twice-per-revolution frequencies. We also explain how to determine the required preview time by breaking it down into separate parts, and we then compare it to the expected preview time available.

  15. Comparison of Two Independent Lidar-Based Pitch Control Designs

    SciTech Connect

    Dunne, F.; Schlipf, D.; Pao, L. Y.; Wright, A. D.; Jonkman, B.; Kelley, N.; Simley, E.

    2012-01-01

    Two different lidar-based feedforward controllers have previously been designed for the NREL 5 MW wind turbine model under separate studies. One uses a finite-impulse-response design, with 5 seconds of preview, and three rotating lidar measurements. The other uses a static-gain design, with the preview time defined by the pitch actuator dynamics, a simulation of a real nacelle-based scanning lidar system, and a lowpass filter defined by the lidar configuration. These controllers are now directly compared under the same lidar configuration, in terms of fatigue load reduction, rotor speed regulation, and power capture. The various differences in design choices are discussed and compared. We also compare frequency plots of individual pitch feedforward and collective pitch feedforward load reductions, and we see that individual pitch feedforward is effective mainly at the once-per-revolution and twice-per-revolution frequencies. We also explain how to determine the required preview time by breaking it down into separate parts, and we then compare it to the expected preview time available.

  16. Development of advanced blade pitching kinematics for cycloturbines and cyclorotors

    NASA Astrophysics Data System (ADS)

    Adams, Zachary Howard

    to achieve optimum performance. A novel inverse method was developed implementing a new semi-empirical curvilinear flow blade aerodynamic coefficient model to predict optimum cycloturbine blade pitch waveforms from the ideal fluid deceleration. These improved blade pitch waveforms were evaluated on a 1.37m diameter by 1.37m span cycloturbine to definitively characterize their improvement over existing blade pitch motions and demonstrate the practicality of a variable blade pitch system. The Fluxline Optimal pitching kinematics outperformed sinusoidal and fixed pitching kinematics. The turbine achieved a mean gross aerodynamic power coefficient of 0.44 (95% confidence interval: [0.388,0.490]) and 0.52 (95% confidence interval: [0.426,0.614]) at tip speed ratios (TSRs) of 1.5 and 2.25 respectively which exceeds all other low TSR vertical axis wind turbines. Two-dimensional incompressible Reynolds-averaged Navier-Stokes computational fluid dynamic simulations were used to characterize higher order effects of the blade interaction with the fluid. These simulations suggest Fluxline Optimal pitch kinematics achieve high power coefficients by evenly extracting energy from the flow without blade stall or detached turbine wakes. Fluxline Theory was adapted to inform the design of high efficiency cyclorotors by incorporating the concept of rotor angle of attack as well as a power and drag loss model for blade support structure. A blade element version of this theory predicts rotor performance. For hovering, a simplified variation of the theory instructs that cyclorotors will achieve the greatest power loading at low disk loadings with high solidity blades pitched to maximum lift coefficient. Increasing lift coefficients in the upstream portion of the rotor disproportionately increases performance compared to magnifying lift in the downstream portion. This suggests airfoil sections that counter curvilinear flow effects could improve hovering efficiency. Additionally, the

  17. Hemispheric lateralization for early auditory processing of lexical tones: dependence on pitch level and pitch contour.

    PubMed

    Wang, Xiao-Dong; Wang, Ming; Chen, Lin

    2013-09-01

    In Mandarin Chinese, a tonal language, pitch level and pitch contour are two dimensions of lexical tones according to their acoustic features (i.e., pitch patterns). A change in pitch level features a step change whereas that in pitch contour features a continuous variation in voice pitch. Currently, relatively little is known about the hemispheric lateralization for the processing of each dimension. To address this issue, we made whole-head electrical recordings of mismatch negativity in native Chinese speakers in response to the contrast of Chinese lexical tones in each dimension. We found that pre-attentive auditory processing of pitch level was obviously lateralized to the right hemisphere whereas there is a tendency for that of pitch contour to be lateralized to the left. We also found that the brain responded faster to pitch level than to pitch contour at a pre-attentive stage. These results indicate that the hemispheric lateralization for early auditory processing of lexical tones depends on the pitch level and pitch contour, and suggest an underlying inter-hemispheric interactive mechanism for the processing.

  18. The viscoelastic flow behavior of pitches

    NASA Astrophysics Data System (ADS)

    Fleurot, Olivier

    1998-11-01

    For the first time, a commercial impregnating coal-tar pitch was air-blown (or heat-treated) for various periods of time to produce series of treated pitches. Each pitch was chemically and rheologically characterized. During air-blowing, the formation of large, aromatic, cross- linked molecules increased the elasticity of the pitch and prevented mesophase formation. During heat-treatment, large, planar, aromatic molecules formed and aggregated in mesophase spheres. These two-phase materials exhibited yield stress behavior. Also, their elasticity was similar to that of air-blown pitches. The flow/microstructure relationship in mesophase pitches was investigated. It was found that the steady and transient shear behaviors of mesophase pitches were qualitatively similar to that of LCPs. Also, the size of the structure decreased with increasing shear rate. Upon cessation of flow, the structure slowly coarsened. New techniques were proposed to estimate (1) relaxation time for structure recovery, and (2) the average elastic constant of mesophase pitches. Using Marrucci's model (originally designed for LCPs) it was possible for the first time to predict mesophase pitches' structure shrinkage during pure shear. Finally, the flow-induced structural development that occurs during extrusion of mesophase pitch through capillaries was observed and accurately predicted by coupling computational fluid dynamics (CFD) to Marrucci's model. Using a viscoelastic stress tensor to characterize the pitch flow behavior, the model was able to accurately predict the magnitude of the vortex experimentally observed at the spinnerette capillary counterbore as well as the extend of die swell at the exit of the capillary.

  19. Numeric aspects in pitch identification: an fMRI study

    PubMed Central

    2011-01-01

    Background Pitch identification had yielded unique response patterns compared to other auditory skills. Selecting one out of numerous pitches distinguished this task from detecting a pitch ascent. Encoding of numerous stimuli had activated the intraparietal sulcus in the visual domain. Therefore, we hypothesized that numerosity encoding during pitch identification activates the intraparietal sulcus as well. Methods To assess pitch identification, the participants had to recognize a single pitch from a set of four possible pitches in each trial. Functional magnetic resonance imaging (fMRI) disentangled neural activation during this four-pitch-choice task from activation during pitch contour perception, tone localization, and pitch discrimination. Results Pitch identification induced bilateral activation in the intraparietal sulcus compared to pitch discrimination. Correct responses in pitch identification correlated with activation in the left intraparietal sulcus. Pitch contour perception activated the superior temporal gyrus conceivably due to the larger range of presented tones. The differentiation between pitch identification and tone localization failed. Activation in an ACC-hippocampus network distinguished pitch discrimination from pitch identification. Conclusion Pitch identification is distinguishable from pitch discrimination on the base of activation in the IPS. IPS activity during pitch identification may be the auditory counterpart of numerosity encoding in the visual domain. PMID:21392373

  20. Video Game Programmers Learn to "Pitch"

    ERIC Educational Resources Information Center

    Nikirk, Martin

    2007-01-01

    New video and computer game ideas reach the stage of production by a company when they are "pitched" by game developers to game publishers. Learning how to "pitch" technology products has great educational value for technology education students. In this article, the author shares his experience with helping his students master…

  1. Learning Novel Musical Pitch via Distributional Learning

    ERIC Educational Resources Information Center

    Ong, Jia Hoong; Burnham, Denis; Stevens, Catherine J.

    2017-01-01

    Because different musical scales use different sets of intervals and, hence, different musical pitches, how do music listeners learn those that are in their native musical system? One possibility is that musical pitches are acquired in the same way as phonemes, that is, via distributional learning, in which learners infer knowledge from the…

  2. Memory for vocal tempo and pitch.

    PubMed

    Boltz, Marilyn G

    2017-03-13

    Two experiments examined the ability to remember the vocal tempo and pitch of different individuals, and the way this information is encoded into the cognitive system. In both studies, participants engaged in an initial familiarisation phase while attending was systematically directed towards different aspects of speakers' voices. Afterwards, they received a tempo or pitch recognition task. Experiment 1 showed that tempo and pitch are both incidentally encoded into memory at levels comparable to intentional learning, and no performance deficit occurs with divided attending. Experiment 2 examined the ability to recognise pitch or tempo when the two dimensions co-varied and found that the presence of one influenced the other: performance was best when both dimensions were positively correlated with one another. As a set, these findings indicate that pitch and tempo are automatically processed in a holistic, integral fashion [Garner, W. R. (1974). The processing of information and structure. Potomac, MD: Erlbaum.] which has a number of cognitive implications.

  3. Surface Electromyography of the Forearm Musculature During the Windmill Softball Pitch

    PubMed Central

    Remaley, D. Trey; Fincham, Bryce; McCullough, Bryan; Davis, Kirk; Nofsinger, Charles; Armstrong, Charles; Stausmire, Julie M.

    2015-01-01

    Background: Previous studies investigating the windmill softball pitch have focused primarily on shoulder musculature and function, collecting limited data on elbow and forearm musculature. Little information is available in the literature regarding the forearm. This study documents forearm muscle electromyographic (EMG) activity that has not been previously published. Purpose: Elbow and upper extremity overuse injuries are on the rise in fast-pitch softball pitchers. This study attempts to describe forearm muscle activity in softball pitchers during the windmill softball pitch. Overuse injuries can be prevented if a better understanding of mechanics is defined. Study Design: Descriptive laboratory study. Methods: Surface EMG and high-speed videography was used to study forearm muscle activation patterns during the windmill softball pitch on 10 female collegiate-level pitchers. Maximum voluntary isometric contraction of each muscle was used as a normalizing value. Each subject was tested during a single laboratory session per pitcher. Data included peak muscle activation, average muscle activation, and time to peak activation for 6 pitch types: fastball, changeup, riseball, curveball, screwball, and dropball. Results: During the first 4 phases, muscle activity (seen as signal strength on the EMG recordings) was limited and static in nature. The greatest activation occurred in phases 5 and 6, with increased signal strength, evidence of stretch-shortening cycle, and different muscle characteristics with each pitch style. These 2 phases of the windmill pitch are where the arm is placed in the 6 o’clock position and then at release of the ball. The flexor carpi ulnaris signal strength was significantly greater than the other forearm flexors. Timing of phases 1 through 5 was successively shorter for each pitch. There was a secondary pattern of activation in the flexor carpi ulnaris in phase 4 for all pitches except the fastball and riseball. Conclusion: During the 6

  4. A Biomechanical Evaluation of the Kinetics for Multiple Pitching Techniques in College-Aged Pitchers

    PubMed Central

    Solomito, Matthew J.; Garibay, Erin J.; Õunpuu, Sylvia; Tate, Janet P.; Nissen, Carl W.

    2013-01-01

    Background: There are a number of studies showing that fastball pitches place greater loads on the shoulder and elbow than the curveball; however, the results of these studies are inconsistent, especially in collegiate-level pitchers. There is also discussion that sliders may produce substantially greater loads than other breaking pitches, but there is little scientific evidence to support this claim. Hypothesis: The curveball and slider/cutter produce greater moments on the shoulder and elbow compared with the fastball and change-up. Study Design: Descriptive laboratory study. Methods: Thirty-six collegiate pitchers were evaluated using motion analysis techniques. All subjects pitched a fastball and a change-up, 29 pitched a curveball, and 20 pitched a slider/cutter. Kinematic data were collected, and kinetic (joint moment) data were computed using standard protocols. A random-intercept, mixed-model regression analysis was used to assess differences in joint moments between pitch types. Results: The greatest glenohumeral and elbow moments were found when pitchers were pitching the fastball (mean ± standard deviation: 80.8 ± 15.5 and 79.2 ± 16.9 N·m, respectively) and the lowest when pitching the change-up (73.2 ± 14.5 and 71.6 ± 15.0 N·m, respectively). The moments produced by the slider/cutter and curveball were similar (74.9 ± 16.4 and 75.6 ± 15.5 N·m at the elbow, respectively) and significantly lower than the moments produced by the fastball (P < .0001). Results also indicate that the change-up produced the lowest joint moments compared with other pitch types. Conclusion: This study shows that the fastball and not the curveball or slider/cutter produced the greatest moments on the college pitcher’s glenohumeral and elbow joints, as previously believed. The study also shows that the change-up may be the safest of the 4 pitch types analyzed. Clinical Relevance: There is a long-held belief that throwing breaking pitches, specifically the slider and

  5. Human echolocation: pitch versus loudness information.

    PubMed

    Schenkman, Bo N; Nilsson, Mats E

    2011-01-01

    Blind persons emit sounds to detect objects by echolocation. Both perceived pitch and perceived loudness of the emitted sound change as they fuse with the reflections from nearby objects. Blind persons generally are better than sighted at echolocation, but it is unclear whether this superiority is related to detection of pitch, loudness, or both. We measured the ability of twelve blind and twenty-five sighted listeners to determine which of two sounds, 500 ms noise bursts, that had been recorded in the presence of a reflecting object in a room with reflecting walls using an artificial head. The sound pairs were original recordings differing in both pitch and loudness, or manipulated recordings with either the pitch or the loudness information removed. Observers responded using a 2AFC method with verbal feedback. For both blind and sighted listeners the performance declined more with the pitch information removed than with the loudness information removed. In addition, the blind performed clearly better than the sighted as long as the pitch information was present, but not when it was removed. Taken together, these results show that the ability to detect pitch is a main factor underlying high performance in human echolocation.

  6. Imperfect pitch: Gabor's uncertainty principle and the pitch of extremely brief sounds.

    PubMed

    Hsieh, I-Hui; Saberi, Kourosh

    2016-02-01

    How brief must a sound be before its pitch is no longer perceived? The uncertainty tradeoff between temporal and spectral resolution (Gabor's principle) limits the minimum duration required for accurate pitch identification or discrimination. Prior studies have reported that pitch can be extracted from sinusoidal pulses as brief as half a cycle. This finding has been used in a number of classic papers to develop models of pitch encoding. We have found that phase randomization, which eliminates timbre confounds, degrades this ability to chance, raising serious concerns over the foundation on which classic pitch models have been built. The current study investigated whether subthreshold pitch cues may still exist in partial-cycle pulses revealed through statistical integration in a time series containing multiple pulses. To this end, we measured frequency-discrimination thresholds in a two-interval forced-choice task for trains of partial-cycle random-phase tone pulses. We found that residual pitch cues exist in these pulses but discriminating them requires an order of magnitude (ten times) larger frequency difference than that reported previously, necessitating a re-evaluation of pitch models built on earlier findings. We also found that as pulse duration is decreased to less than two cycles its pitch becomes biased toward higher frequencies, consistent with predictions of an auto-correlation model of pitch extraction.

  7. Development of carbon-carbon composites from solvent extracted pitch

    SciTech Connect

    1996-06-24

    There are several methods used to fabricate carbon-carbon composites. One used extensively in the fabrication of aerospace components such as rocket nozzles and reentry vehicle nosetips, as well as commercial components for furnace fixturing and glass manufacturing, is the densification of a woven preform with molten pitch, and the subsequent conversion of the pitch to graphite through heat treatment. Two types of pitch are used in this process; coal tar pitch and petroleum pitch. The objective of this program was to determine if a pitch produced by the direct extraction of coal could be used as a substitute for these pitches in the fabrication of carbon-carbon composites. The program involved comparing solvent extracted pitch with currently accepted pitches and rigidizing a carbon-carbon preform with solvent extracted pitch for comparison with carbon-carbon fabricated with currently available pitch.

  8. SOLARMAX/Electron Pitch Angle Anisotropy Distributions

    NASA Technical Reports Server (NTRS)

    McKenzie, David L.; Anderson, Phillip C.

    2002-01-01

    This final research report summarizes the scientific work performed by The Aerospace Corporation on SOLARMAX/Electron Pitch Angle Anisotropy Distributions. The period of performance was from June 1, 2000 to December 31, 2001.

  9. Method for extruding pitch based foam

    DOEpatents

    Klett, James W.

    2002-01-01

    A method and apparatus for extruding pitch based foam is disclosed. The method includes the steps of: forming a viscous pitch foam; passing the precursor through an extrusion tube; and subjecting the precursor in said extrusion tube to a temperature gradient which varies along the length of the extrusion tube to form an extruded carbon foam. The apparatus includes an extrusion tube having a passageway communicatively connected to a chamber in which a viscous pitch foam formed in the chamber paring through the extrusion tube, and a heating mechanism in thermal communication with the tube for heating the viscous pitch foam along the length of the tube in accordance with a predetermined temperature gradient.

  10. Experience-dependent enhancement of pitch-specific responses in the auditory cortex is limited to acceleration rates in normal voice range

    PubMed Central

    Krishnan, Ananthanarayan; Gandour, Jackson T.; Suresh, Chandan H.

    2015-01-01

    The aim of this study is to determine how pitch acceleration rates within and outside the normal pitch range may influence latency and amplitude of cortical pitch-specific responses (CPR) as a function of language experience (Chinese, English). Responses were elicited from a set of four pitch stimuli chosen to represent a range of acceleration rates (two each inside and outside the normal voice range) imposed on the high rising Mandarin Tone 2. Pitch-relevant neural activity, as reflected in the latency and amplitude of scalp-recorded CPR components, varied depending on language-experience and pitch acceleration of dynamic, time-varying pitch contours. Peak latencies of CPR components were shorter in the Chinese than the English group across stimuli. Chinese participants showed greater amplitude than English for CPR components at both frontocentral and temporal electrode sites in response to pitch contours with acceleration rates inside the normal voice pitch range as compared to pitch contours with acceleration rates that exceed the normal range. As indexed by CPR amplitude at the temporal sites, a rightward asymmetry was observed for the Chinese group only. Only over the right temporal site was amplitude greater in the Chinese group relative to the English. These findings may suggest that the neural mechanism(s) underlying processing of pitch in the right auditory cortex reflect experience-dependent modulation of sensitivity to acceleration in just those rising pitch contours that fall within the bounds of one’s native language. More broadly, enhancement of native pitch stimuli and stronger rightward asymmetry of CPR components in the Chinese group is consistent with the notion that long-term experience shapes adaptive, distributed hierarchical pitch processing in the auditory cortex, and reflects an interaction with higher-order, extrasensory processes beyond the sensory memory trace. PMID:26166727

  11. Particle chaos and pitch angle scattering

    NASA Technical Reports Server (NTRS)

    Burkhart, G. R.; Dusenbery, P. B.; Speiser, T. W.

    1995-01-01

    Pitch angle scattering is a factor that helps determine the dawn-to-dusk current, controls particle energization, and it has also been used as a remote probe of the current sheet structure. Previous studies have interpreted their results under the exception that randomization will be greatest when the ratio of the two timescales of motion (gyration parallel to and perpendicular to the current sheet) is closet to one. Recently, the average expotential divergence rate (AEDR) has been calculated for particle motion in a hyperbolic current sheet (Chen, 1992). It is claimed that this AEDR measures the degree of chaos and therefore may be thought to measure the randomization. In contrast to previous expectations, the AEDR is not maximized when Kappa is approximately equal to 1 but instead increases with decreasing Kappa. Also contrary to previous expectations, the AEDR is dependent upon the parameter b(sub z). In response to the challenge to previous expectations that has been raised by this calculation of the AEDR, we have investigated the dependence of a measure of particle pitch angle scattering on both the parameters Kappa and b(sub z). We find that, as was previously expected, particle pitch angle scattering is maximized near Kappa = 1 provided that Kappa/b(sub z) greater than 1. In the opposite regime, Kappa/b(sub z) less than 1, we find that particle pitch angle scattering is still largest when the two timescales are equal, but the ratio of the timescales is proportional to b(sub z). In this second regime, particle pitch angle scattering is not due to randomization, but is instead due to a systematic pitch angle change. This result shows that particle pitch angle scattering need not be due to randomization and indicates how a measure of pitch angle scattering can exhibit a different behavior than a measure of chaos.

  12. Effects of culture on musical pitch perception.

    PubMed

    Wong, Patrick C M; Ciocca, Valter; Chan, Alice H D; Ha, Louisa Y Y; Tan, Li-Hai; Peretz, Isabelle

    2012-01-01

    The strong association between music and speech has been supported by recent research focusing on musicians' superior abilities in second language learning and neural encoding of foreign speech sounds. However, evidence for a double association--the influence of linguistic background on music pitch processing and disorders--remains elusive. Because languages differ in their usage of elements (e.g., pitch) that are also essential for music, a unique opportunity for examining such language-to-music associations comes from a cross-cultural (linguistic) comparison of congenital amusia, a neurogenetic disorder affecting the music (pitch and rhythm) processing of about 5% of the Western population. In the present study, two populations (Hong Kong and Canada) were compared. One spoke a tone language in which differences in voice pitch correspond to differences in word meaning (in Hong Kong Cantonese, /si/ means 'teacher' and 'to try' when spoken in a high and mid pitch pattern, respectively). Using the On-line Identification Test of Congenital Amusia, we found Cantonese speakers as a group tend to show enhanced pitch perception ability compared to speakers of Canadian French and English (non-tone languages). This enhanced ability occurs in the absence of differences in rhythmic perception and persists even after relevant factors such as musical background and age were controlled. Following a common definition of amusia (5% of the population), we found Hong Kong pitch amusics also show enhanced pitch abilities relative to their Canadian counterparts. These findings not only provide critical evidence for a double association of music and speech, but also argue for the reconceptualization of communicative disorders within a cultural framework. Along with recent studies documenting cultural differences in visual perception, our auditory evidence challenges the common assumption of universality of basic mental processes and speaks to the domain generality of culture

  13. Perceptual pitch deficits coexist with pitch production difficulties in music but not Mandarin speech.

    PubMed

    Yang, Wu-Xia; Feng, Jie; Huang, Wan-Ting; Zhang, Cheng-Xiang; Nan, Yun

    2013-01-01

    Congenital amusia is a musical disorder that mainly affects pitch perception. Among Mandarin speakers, some amusics also have difficulties in processing lexical tones (tone agnosics). To examine to what extent these perceptual deficits may be related to pitch production impairments in music and Mandarin speech, eight amusics, eight tone agnosics, and 12 age- and IQ-matched normal native Mandarin speakers were asked to imitate music note sequences and Mandarin words of comparable lengths. The results indicated that both the amusics and tone agnosics underperformed the controls on musical pitch production. However, tone agnosics performed no worse than the amusics, suggesting that lexical tone perception deficits may not aggravate musical pitch production difficulties. Moreover, these three groups were all able to imitate lexical tones with perfect intelligibility. Taken together, the current study shows that perceptual musical pitch and lexical tone deficits might coexist with musical pitch production difficulties. But at the same time these perceptual pitch deficits might not affect lexical tone production or the intelligibility of the speech words that were produced. The perception-production relationship for pitch among individuals with perceptual pitch deficits may be, therefore, domain-dependent.

  14. Heave and Pitch Dynamics of Shallow Draft Surface Vehicles

    DTIC Science & Technology

    2012-04-10

    STATEMENT 13 . SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: a. REPORT 19a. NAME OF RESPONSIBLE PERSON 19b. TELEPHONE... 13 6.0 Conclusions...angle relative to wave ssz Heave steady state displacement  Pitch displacement a Pitch amplitude ss Pitch steady state displacement  Pitch

  15. Coordination pattern of baseball pitching among young pitchers of various ages and velocity levels.

    PubMed

    Chen, Hsiu-Hui; Liu, Chiang; Yang, Wen-Wen

    2016-09-01

    This study compared the whole-body movement coordination of pitching among 72 baseball players of various ages and velocity levels. Participants were classified as senior, junior, and little according to their age, with each group comprising 24 players. The velocity levels of the high-velocity (the top eight) and low-velocity (the lowest eight) groups were classified according to their pitching velocity. During pitching, the coordinates of 15 markers attached to the major joints of the whole-body movement system were collected for analysis. Sixteen kinematic parameters were calculated to compare the groups and velocity levels. Principal component analysis (PCA) was conducted to quantify the coordination pattern of pitching movement. The results were as follows: (1) five position and two velocity parameters significantly differed among the age groups, and two position and one velocity parameters significantly differed between the high- and low-velocity groups. (2) The coordination patterns of pitching movement could be described using three components, of which the eigenvalues and contents varied according to age and velocity level. In conclusion, the senior and junior players showed greater elbow angular velocity, whereas the little players exhibited a wider shoulder angle only at the beginning of pitching. The players with high velocity exhibited higher trunk and shoulder rotation velocity. The variations among groups found using PCA and kinematics parameter analyses were consistent.

  16. A Neuronal Network Model for Pitch Selectivity and Representation

    PubMed Central

    Huang, Chengcheng; Rinzel, John

    2016-01-01

    Pitch is a perceptual correlate of periodicity. Sounds with distinct spectra can elicit the same pitch. Despite the importance of pitch perception, understanding the cellular mechanism of pitch perception is still a major challenge and a mechanistic model of pitch is lacking. A multi-stage neuronal network model is developed for pitch frequency estimation using biophysically-based, high-resolution coincidence detector neurons. The neuronal units respond only to highly coincident input among convergent auditory nerve fibers across frequency channels. Their selectivity for only very fast rising slopes of convergent input enables these slope-detectors to distinguish the most prominent coincidences in multi-peaked input time courses. Pitch can then be estimated from the first-order interspike intervals of the slope-detectors. The regular firing pattern of the slope-detector neurons are similar for sounds sharing the same pitch despite the distinct timbres. The decoded pitch strengths also correlate well with the salience of pitch perception as reported by human listeners. Therefore, our model can serve as a neural representation for pitch. Our model performs successfully in estimating the pitch of missing fundamental complexes and reproducing the pitch variation with respect to the frequency shift of inharmonic complexes. It also accounts for the phase sensitivity of pitch perception in the cases of Schroeder phase, alternating phase and random phase relationships. Moreover, our model can also be applied to stochastic sound stimuli, iterated-ripple-noise, and account for their multiple pitch perceptions. PMID:27378900

  17. Exploring the Relevance of the Personal and Social Responsibility Model in Adapted Physical Activity: A Collective Case Study

    ERIC Educational Resources Information Center

    Wright, Paul M.; White, Katherine; Gaebler-Spira, Deborah

    2004-01-01

    The purpose of this study was to examine the application of the Personal and Social Responsibility Model (PSRM) in an adapted physical activity program. Although the PSRM was developed for use with underserved youth, scholars in the field of adapted physical activity have noted its potential relevance for children with disabilities. Using a…

  18. Prosodic Adaptations to Pitch Perturbation in Running Speech

    ERIC Educational Resources Information Center

    Patel, Rupal; Niziolek, Caroline; Reilly, Kevin; Guenther, Frank H.

    2011-01-01

    Purpose: A feedback perturbation paradigm was used to investigate whether prosodic cues are controlled independently or in an integrated fashion during sentence production. Method: Twenty-one healthy speakers of American English were asked to produce sentences with emphatic stress while receiving real-time auditory feedback of their productions.…

  19. Pitch Perception in the First Year of Life, a Comparison of Lexical Tones and Musical Pitch

    PubMed Central

    Chen, Ao; Stevens, Catherine J.; Kager, René

    2017-01-01

    Pitch variation is pervasive in speech, regardless of the language to which infants are exposed. Lexical tone is influenced by general sensitivity to pitch. We examined whether the development in lexical tone perception may develop in parallel with perception of pitch in other cognitive domains namely music. Using a visual fixation paradigm, 100 and one 4- and 12-month-old Dutch infants were tested on their discrimination of Chinese rising and dipping lexical tones as well as comparable three-note musical pitch contours. The 4-month-old infants failed to show a discrimination effect in either condition, whereas the 12-month-old infants succeeded in both conditions. These results suggest that lexical tone perception may reflect and relate to general pitch perception abilities, which may serve as a basis for developing more complex language and musical skills. PMID:28337157

  20. Pitch perception deficits in nonverbal learning disability.

    PubMed

    Fernández-Prieto, I; Caprile, C; Tinoco-González, D; Ristol-Orriols, B; López-Sala, A; Póo-Argüelles, P; Pons, F; Navarra, J

    2016-12-01

    The nonverbal learning disability (NLD) is a neurological dysfunction that affects cognitive functions predominantly related to the right hemisphere such as spatial and abstract reasoning. Previous evidence in healthy adults suggests that acoustic pitch (i.e., the relative difference in frequency between sounds) is, under certain conditions, encoded in specific areas of the right hemisphere that also encode the spatial elevation of external objects (e.g., high vs. low position). Taking this evidence into account, we explored the perception of pitch in preadolescents and adolescents with NLD and in a group of healthy participants matched by age, gender, musical knowledge and handedness. Participants performed four speeded tests: a stimulus detection test and three perceptual categorization tests based on colour, spatial position and pitch. Results revealed that both groups were equally fast at detecting visual targets and categorizing visual stimuli according to their colour. In contrast, the NLD group showed slower responses than the control group when categorizing space (direction of a visual object) and pitch (direction of a change in sound frequency). This pattern of results suggests the presence of a subtle deficit at judging pitch in NLD along with the traditionally-described difficulties in spatial processing.

  1. An Improved Manufacturing Approach for Discrete Silicon Microneedle Arrays with Tunable Height-Pitch Ratio

    PubMed Central

    Wang, Renxin; Wang, Wei; Li, Zhihong

    2016-01-01

    Silicon microneedle arrays (MNAs) have been widely studied due to their potential in various transdermal applications. However, discrete MNAs, as a preferred choice to fabricate flexible penetrating devices that could adapt curved and elastic tissue, are rarely reported. Furthermore, the reported discrete MNAs have disadvantages lying in uniformity and height-pitch ratio. Therefore, an improved technique is developed to manufacture discrete MNA with tunable height-pitch ratio, which involves KOH-dicing-KOH process. The detailed process is sketched and simulated to illustrate the formation of microneedles. Furthermore, the undercutting of convex mask in two KOH etching steps are mathematically analyzed, in order to reveal the relationship between etching depth and mask dimension. Subsequently, fabrication results demonstrate KOH-dicing-KOH process. {321} facet is figured out as the surface of octagonal pyramid microneedle. MNAs with diverse height and pitch are also presented to identify the versatility of this approach. At last, the metallization is realized via successive electroplating. PMID:27735837

  2. An Improved Manufacturing Approach for Discrete Silicon Microneedle Arrays with Tunable Height-Pitch Ratio.

    PubMed

    Wang, Renxin; Wang, Wei; Li, Zhihong

    2016-10-09

    Silicon microneedle arrays (MNAs) have been widely studied due to their potential in various transdermal applications. However, discrete MNAs, as a preferred choice to fabricate flexible penetrating devices that could adapt curved and elastic tissue, are rarely reported. Furthermore, the reported discrete MNAs have disadvantages lying in uniformity and height-pitch ratio. Therefore, an improved technique is developed to manufacture discrete MNA with tunable height-pitch ratio, which involves KOH-dicing-KOH process. The detailed process is sketched and simulated to illustrate the formation of microneedles. Furthermore, the undercutting of convex mask in two KOH etching steps are mathematically analyzed, in order to reveal the relationship between etching depth and mask dimension. Subsequently, fabrication results demonstrate KOH-dicing-KOH process. {321} facet is figured out as the surface of octagonal pyramid microneedle. MNAs with diverse height and pitch are also presented to identify the versatility of this approach. At last, the metallization is realized via successive electroplating.

  3. Variable pitch reconstruction using John's equation.

    PubMed

    Karbeyaz, Başak Ulker; Naidu, Ram C; Ying, Zhengrong; Simanovsky, Sergey B; Hirsch, Matthew W; Schafer, David A; Crawford, Carl R

    2008-01-01

    We present an algorithm to reconstruct helical cone beam computed tomography (CT) data acquired at variable pitch. The algorithm extracts a halfscan segment of projections using an extended version of the advanced single slice rebinning (ASSR) algorithm. ASSR rebins constant pitch cone beam data to fan beam projections that approximately lie on a plane that is tilted to optimally fit the source helix. For variable pitch, the error between the tilted plane chosen by ASSR and the source helix increases, resulting in increased image artifacts. To reduce the artifacts, we choose a reconstruction plane, which is tilted and shifted relative to the source trajectory. We then correct rebinned fan beam data using John's equation to virtually move the source into the tilted and shifted reconstruction plane. Results obtained from simulated phantom images and scanner images demonstrate the applicability of the proposed algorithm.

  4. Muscle activation patterns of the upper and lower extremity during the windmill softball pitch.

    PubMed

    Oliver, Gretchen D; Plummer, Hillary A; Keeley, David W

    2011-06-01

    Fast-pitch softball has become an increasingly popular sport for female athletes. There has been little research examining the windmill softball pitch in the literature. The purpose of this study was to describe the muscle activation patterns of 3 upper extremity muscles (biceps, triceps, and rhomboids [scapular stabilizers]) and 2 lower extremity muscles (gluteus maximus and medius) during the 5 phases of the windmill softball pitch. Data describing muscle activation were collected on 7 postpubescent softball pitchers (age 17.7 ± 2.6 years; height 169 ± 5.4 cm; mass 69.1 ± 5.4 kg). Surface electromyographic data were collected using a Myopac Jr 10-channel amplifier (RUN Technologies Scientific Systems, Laguna Hills, CA, USA) synchronized with The MotionMonitor™ motion capture system (Innovative Sports Training Inc, Chicago IL, USA) and presented as a percent of maximum voluntary isometric contraction. Gluteus maximus activity reached (196.3% maximum voluntary isometric contraction [MVIC]), whereas gluteus medius activity was consistent during the single leg support of phase 3 (101.2% MVIC). Biceps brachii activity was greatest during phase 4 of the pitching motion. Triceps brachii activation was consistently >150% MVIC throughout the entire pitching motion, whereas the scapular stabilizers were most active during phase 2 (170.1% MVIC). The results of this study indicate the extent to which muscles are activated during the windmill softball pitch, and this knowledge can lead to the development of proper preventative and rehabilitative muscle strengthening programs. In addition, clinicians will be able to incorporate strengthening exercises that mimic the timing of maximal muscle activation most used during the windmill pitching phases.

  5. The thickness of musical pitch: psychophysical evidence for linguistic relativity.

    PubMed

    Dolscheid, Sarah; Shayan, Shakila; Majid, Asifa; Casasanto, Daniel

    2013-05-01

    Do people who speak different languages think differently, even when they are not using language? To find out, we used nonlinguistic psychophysical tasks to compare mental representations of musical pitch in native speakers of Dutch and Farsi. Dutch speakers describe pitches as high (hoog) or low (laag), whereas Farsi speakers describe pitches as thin (nazok) or thick (koloft). Differences in language were reflected in differences in performance on two pitch-reproduction tasks, even though the tasks used simple, nonlinguistic stimuli and responses. To test whether experience using language influences mental representations of pitch, we trained native Dutch speakers to describe pitch in terms of thickness, as Farsi speakers do. After the training, Dutch speakers' performance on a nonlinguistic psychophysical task resembled the performance of native Farsi speakers. People who use different linguistic space-pitch metaphors also think about pitch differently. Language can play a causal role in shaping nonlinguistic representations of musical pitch.

  6. Pitch ranking, electrode discrimination, and physiological spread-of-excitation using Cochlear's dual-electrode mode.

    PubMed

    Goehring, Jenny L; Neff, Donna L; Baudhuin, Jacquelyn L; Hughes, Michelle L

    2014-08-01

    This study compared pitch ranking, electrode discrimination, and electrically evoked compound action potential (ECAP) spatial excitation patterns for adjacent physical electrodes (PEs) and the corresponding dual electrodes (DEs) for newer-generation Cochlear devices (Cochlear Ltd., Macquarie, New South Wales, Australia). The first goal was to determine whether pitch ranking and electrode discrimination yield similar outcomes for PEs and DEs. The second goal was to determine if the amount of spatial separation among ECAP excitation patterns (separation index, Σ) between adjacent PEs and the PE-DE pairs can predict performance on the psychophysical tasks. Using non-adaptive procedures, 13 subjects completed pitch ranking and electrode discrimination for adjacent PEs and the corresponding PE-DE pairs (DE versus each flanking PE) from the basal, middle, and apical electrode regions. Analysis of d' scores indicated that pitch-ranking and electrode-discrimination scores were not significantly different, but rather produced similar levels of performance. As expected, accuracy was significantly better for the PE-PE comparison than either PE-DE comparison. Correlations of the psychophysical versus ECAP Σ measures were positive; however, not all test/region correlations were significant across the array. Thus, the ECAP separation index is not sensitive enough to predict performance on behavioral tasks of pitch ranking or electrode discrimination for adjacent PEs or corresponding DEs.

  7. Small pixel pitch MCT IR-modules

    NASA Astrophysics Data System (ADS)

    Lutz, H.; Breiter, R.; Eich, D.; Figgemeier, H.; Fries, P.; Rutzinger, S.; Wendler, J.

    2016-05-01

    It is only some years ago, since VGA format detectors in 15μm pitch, manufactured with AIM's MCT n-on-p LPE standard technology, have been introduced to replace TV/4 format detector arrays as a system upgrade. In recent years a rapid increase in the demand for higher resolution, while preserving high thermal resolution, compactness and low power budget is observed. To satisfy these needs AIM has realized first prototypes of MWIR XGA format (1024x768) detector arrays in 10μm pitch. They fit in the same compact dewar as 640x512, 15μm pitch detector arrays. Therefore, they are best suited for system upgrade purposes to benefit from higher spatial resolution and keep cost on system level low. By combining pitch size reduction with recent development progress in the fields of miniature cryocoolers, short dewars and high operating temperatures the way ahead to ultra-compact high performance MWIR-modules is prepared. For cost reduction MBE grown MCT on commercially available GaAs substrates is introduced at AIM. Recently, 640x512, 15μm pitch FPAs, grown with MBE have successfully passed long-term high temperature storage tests as a crucial step towards serial production readiness level for use in future products. Pitch size reduction is not limited to arrays sensitive in the MWIR, but is of great interest for high performance LWIR or 3rd Gen solutions. Some applications such as rotorcraft pilotage require superior spatial resolution in a compact design to master severe weather conditions or degraded visual environment such as brown-out. For these applications AIM is developing both LWIR as well as dual band detector arrays in HD-format (1280x720) with 12μm pitch. This paper will present latest results in the development of detector arrays with small pitch sizes of 10μm and 12μm at AIM, together with their usage to realize compact cooled IR-modules.

  8. Thread gauge for measuring thread pitch diameters

    DOEpatents

    Brewster, A.L.

    1985-11-19

    A thread gauge which attaches to a vernier caliper to measure the thread pitch diameter of both externally threaded and internally threaded parts is disclosed. A pair of anvils are externally threaded with threads having the same pitch as those of the threaded part. Each anvil is mounted on a stem having a ball on which the anvil can rotate to properly mate with the parts to which the anvils are applied. The stems are detachably secured to the caliper blades by attachment collars having keyhole openings for receiving the stems and caliper blades. A set screw is used to secure each collar on its caliper blade. 2 figs.

  9. Thread gauge for measuring thread pitch diameters

    DOEpatents

    Brewster, Albert L.

    1985-01-01

    A thread gauge which attaches to a vernier caliper to measure the thread pitch diameter of both externally threaded and internally threaded parts. A pair of anvils are externally threaded with threads having the same pitch as those of the threaded part. Each anvil is mounted on a stem having a ball on which the anvil can rotate to properly mate with the parts to which the anvils are applied. The stems are detachably secured to the caliper blades by attachment collars having keyhole openings for receiving the stems and caliper blades. A set screw is used to secure each collar on its caliper blade.

  10. The effects of stride technique and pitch location on slo-pitch batting.

    PubMed

    Wu, Tom; Gervais, Pierre; Baudin, Pierre; Bouffard, Marcel

    2011-11-01

    In slo-pitch softball, the ball is delivered in an arc trajectory with a moderate velocity; hence, batters have time to adjust their stride technique based on the pitched ball location. The purpose of this study was to examine the influence of stride technique and pitched ball location on the mechanics of slo-pitch batting. A two-way ANOVA of two locations of pitch (inside and outside) x three strides (open, parallel, and closed) repeated measure study was conducted in this study. The results showed that the stride technique and pitched ball location did not have a consistent impact on the participants across different batting conditions, so the study recommends slo-pitch batters to explore different stride techniques when striking the ball. Further, to better understand the generalizability of the findings, the results indicated that participants were quite homogeneous as a group. Hence, coaches and educators may apply the findings from this study to other players with similar skill level.

  11. Attending to pitch information inhibits processing of pitch information: the curious case of amusia.

    PubMed

    Zendel, Benjamin Rich; Lagrois, Marie-Élaine; Robitaille, Nicolas; Peretz, Isabelle

    2015-03-04

    In normal listeners, the tonal rules of music guide musical expectancy. In a minority of individuals, known as amusics, the processing of tonality is disordered, which results in severe musical deficits. It has been shown that the tonal rules of music are neurally encoded, but not consciously available in amusics. Previous neurophysiological studies have not explicitly controlled the level of attention in tasks where participants ignored the tonal structure of the stimuli. Here, we test whether access to tonal knowledge can be demonstrated in congenital amusia when attention is controlled. Electric brain responses were recorded while asking participants to detect an individually adjusted near-threshold click in a melody. In half the melodies, a note was inserted that violated the tonal rules of music. In a second task, participants were presented with the same melodies but were required to detect the tonal deviation. Both tasks required sustained attention, thus conscious access to the rules of tonality was manipulated. In the click-detection task, the pitch deviants evoked an early right anterior negativity (ERAN) in both groups. In the pitch-detection task, the pitch deviants evoked an ERAN and P600 in controls but not in amusics. These results indicate that pitch regularities are represented in the cortex of amusics, but are not consciously available. Moreover, performing a pitch-judgment task eliminated the ERAN in amusics, suggesting that attending to pitch information interferes with perception of pitch. We propose that an impaired top-down frontotemporal projection is responsible for this disorder.

  12. LANGUAGE EXPERIENCE SHAPES PROCESSING OF PITCH RELEVANT INFORMATION IN THE HUMAN BRAINSTEM AND AUDITORY CORTEX: ELECTROPHYSIOLOGICAL EVIDENCE

    PubMed Central

    Krishnan, Ananthanarayan; Gandour, Jackson T.

    2015-01-01

    -term experience shapes this adaptive process wherein the top-down connections provide selective gating of inputs to both cortical and subcortical structures to enhance neural responses to specific behaviorally-relevant attributes of the stimulus. A theoretical framework for a neural network is proposed involving coordination between local, feedforward, and feedback components that can account for experience-dependent enhancement of pitch representations at multiple levels of the auditory pathway. The ability to record brainstem and cortical pitch relevant responses concurrently may provide a new window to evaluate the online interplay between feedback, feedforward, and local intrinsic components in the hierarchical processing of pitch relevant information. PMID:25838636

  13. Preaccentual Pitch and Speaker Attitude in Dutch.

    ERIC Educational Resources Information Center

    Grabe, Esther; Gussenhoven, Carlos; Haan, Judith; Marsi, Erwin; Post, Brecht Je

    1998-01-01

    Focuses on the communicative significance of the pitch of the initial unstressed syllables in Dutch intonation contours, as may be heard, for instance, on unstressed utterance-initial function words like "Ze zijn" in "Ze zijn klaar (they are ready), or the initial unstressed syllables of utterance-initial polysyllabic words, like…

  14. Chemical activation of carbon mesophase pitches.

    PubMed

    Mora, E; Blanco, C; Pajares, J A; Santamaría, R; Menéndez, R

    2006-06-01

    This paper studies the chemical activation of mesophase pitches of different origins in order to obtain activated carbons suitable for use as electrodes in supercapacitors. The effect that the activating agent (NaOH, LiOH, and KOH), the alkaline hydroxide/pitch ratio, and the activation temperature had on the characteristics of the resultant activated carbons was studied. LiOH was found to be a noneffective activating agent, while activation with NaOH and KOH yielded activated carbons with high apparent surface areas and pore volumes. The increase of the KOH/pitch ratio caused an increase of the chemical attack on the carbon, producing higher burnoffs and development of porosity. Extremely high apparent surface areas were obtained when the petroleum pitch was activated with 5:1 KOH/carbon ratio. The increase of the activation temperature caused an increase of the burnoff, although the differences were not as significant as those derived from the use of different proportions of activating agent.

  15. Control Engineering Analysis of Mechanical Pitch Systems

    NASA Astrophysics Data System (ADS)

    Bernicke, Olaf; Gauterin, Eckhard; Schulte, Horst; Zajac, Michal

    2014-12-01

    With the help of a local stability analysis the coefficient range of a discrete damper, used for centrifugal forced, mechanical pitch system of small wind turbines (SWT), is gained for equilibrium points. - By a global stability analysis the gained coefficient range can be validated. An appropriate approach by Takagi-Sugeno is presented in the paper.

  16. Pitch-catch only ultrasonic fluid densitometer

    DOEpatents

    Greenwood, M.S.; Harris, R.V.

    1999-03-23

    The present invention is an ultrasonic fluid densitometer that uses a material wedge and pitch-catch only ultrasonic transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface. 6 figs.

  17. Pitch-catch only ultrasonic fluid densitometer

    DOEpatents

    Greenwood, Margaret S.; Harris, Robert V.

    1999-01-01

    The present invention is an ultrasonic fluid densitometer that uses a material wedge and pitch-catch only ultrasonic transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface.

  18. Prelinguistic Pitch Patterns Expressing "Communication" and "Apprehension"

    ERIC Educational Resources Information Center

    Papaeliou, Christina F.; Trevarthen, Colwyn

    2006-01-01

    This study examined whether pitch patterns of prelinguistic vocalizations could discriminate between social vocalizations, uttered apparently with the intention to communicate, and "private" speech, related to solitary activities as an expression of "thinking". Four healthy ten month old English-speaking infants (2 boys and 2 girls) were…

  19. Pitch then power: limitations to acceleration in quadrupeds.

    PubMed

    Williams, Sarah B; Tan, Huiling; Usherwood, James R; Wilson, Alan M

    2009-10-23

    Rapid acceleration and deceleration are vital for survival in many predator and prey animals and are important attributes of animal and human athletes. Adaptations for acceleration and deceleration are therefore likely to experience strong selective pressures--both natural and artificial. Here, we explore the mechanical and physiological constraints to acceleration. We examined two elite athletes bred and trained for acceleration performance (polo ponies and racing greyhounds), when performing maximal acceleration (and deceleration for ponies) in a competitive setting. We show that maximum acceleration and deceleration ability may be accounted for by two simple limits, one mechanical and one physiological. At low speed, acceleration and deceleration may be limited by the geometric constraints of avoiding net nose-up or tail-up pitching, respectively. At higher speeds, muscle power appears to limit acceleration.

  20. Process for the preparation of mesophase pitches

    SciTech Connect

    Tsuchitani, M.; Naito, S.; Nakajima, R.

    1989-05-11

    A process is described for preparing a mesophase pitch with a Mettler method softening point of lower than 320/sup 0/C, a mesophase content of higher than 90% when examined on a polarized microscope, a quinoline insoluble content of lower than 20% and a xylene soluble content of lower than 20% for manufacturing high performance carbon fibers comprising: (a) subjecting a heavy oil of petroleum or coal origin, or a heavy component obtainable from the heavy oil, the oil or component having substantially no xylene insoluble component, to a heat treatment in a tubular heater at a temperature of 400/sup 0/ to 600/sup 0/C under a pressure of 1 to 100 Kg/cm/sup 2/.G measured at the outlet of the tubular heater for 1 to 2000 sec so as to obtain a heat-treated material having 3 to 30 wt% of xylene insoluble component; (b) adding to the thus heat-treated material a monocyclic aromatic hydrocarbon solvent in an amount of 1 to 5 times on the heat-treated material, and recovering the newly formed insoluble component as an essentially isotropic high molecular weight bituminous material; (c) subjecting the high molecular weight bituminous material to a hydrogenation treatment at a temperature of 400/sup 0/ to 460/sup 0/C and a pressure of 20 to 200 Kg/cm/sup 2/.G with the addition of 1 to 5 times amount of a hydrogen-donating solvent based on the high molecular weight bituminous material thereby obtaining an essentially isotropic hydrogenated pitch; and (d) heat treating the hydrogenated pitch at 350/sup 0/ to 500/sup 0/C under a pressure up to atmospheric pressure to convert the hydrogenated pitch into the mesophase pitch.

  1. Auditory imagery and the poor-pitch singer.

    PubMed

    Pfordresher, Peter Q; Halpern, Andrea R

    2013-08-01

    The vocal imitation of pitch by singing requires one to plan laryngeal movements on the basis of anticipated target pitch events. This process may rely on auditory imagery, which has been shown to activate motor planning areas. As such, we hypothesized that poor-pitch singing, although not typically associated with deficient pitch perception, may be associated with deficient auditory imagery. Participants vocally imitated simple pitch sequences by singing, discriminated pitch pairs on the basis of pitch height, and completed an auditory imagery self-report questionnaire (the Bucknell Auditory Imagery Scale). The percentage of trials participants sung in tune correlated significantly with self-reports of vividness for auditory imagery, although not with the ability to control auditory imagery. Pitch discrimination was not predicted by auditory imagery scores. The results thus support a link between auditory imagery and vocal imitation.

  2. 14 CFR 35.21 - Variable and reversible pitch propellers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: PROPELLERS Design and Construction § 35.21 Variable and... unintended travel of the propeller blades to a position below the in-flight low-pitch position. The extent of... blade pitch below the in-flight low pitch position, provisions must be made to sense and indicate to...

  3. 14 CFR 35.21 - Variable and reversible pitch propellers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: PROPELLERS Design and Construction § 35.21 Variable and... unintended travel of the propeller blades to a position below the in-flight low-pitch position. The extent of... blade pitch below the in-flight low pitch position, provisions must be made to sense and indicate to...

  4. 14 CFR 35.21 - Variable and reversible pitch propellers.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: PROPELLERS Design and Construction § 35.21 Variable and... unintended travel of the propeller blades to a position below the in-flight low-pitch position. The extent of... blade pitch below the in-flight low pitch position, provisions must be made to sense and indicate to...

  5. 14 CFR 35.21 - Variable and reversible pitch propellers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: PROPELLERS Design and Construction § 35.21 Variable and... unintended travel of the propeller blades to a position below the in-flight low-pitch position. The extent of... blade pitch below the in-flight low pitch position, provisions must be made to sense and indicate to...

  6. 14 CFR 35.21 - Variable and reversible pitch propellers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: PROPELLERS Design and Construction § 35.21 Variable and... unintended travel of the propeller blades to a position below the in-flight low-pitch position. The extent of... blade pitch below the in-flight low pitch position, provisions must be made to sense and indicate to...

  7. Spatial Representation of Pitch Height: The SMARC Effect

    ERIC Educational Resources Information Center

    Rusconi, Elena; Kwan, Bonnie; Giordano, Bruno L.; Umilta, Carlo; Butterworth, Brian

    2006-01-01

    Through the preferential pairing of response positions to pitch, here we show that the internal representation of pitch height is spatial in nature and affects performance, especially in musically trained participants, when response alternatives are either vertically or horizontally aligned. The finding that our cognitive system maps pitch height…

  8. On Older Listeners' Ability to Perceive Dynamic Pitch

    ERIC Educational Resources Information Center

    Shen, Jing; Wright, Richard; Souza, Pamela E.

    2016-01-01

    Purpose: Natural speech comes with variation in pitch, which serves as an important cue for speech recognition. The present study investigated older listeners' dynamic pitch perception with a focus on interindividual variability. In particular, we asked whether some of the older listeners' inability to perceive dynamic pitch stems from the higher…

  9. Memory for Melody: Infants Use a Relative Pitch Code

    ERIC Educational Resources Information Center

    Plantinga, Judy; Trainor, Laurel J.

    2005-01-01

    Pitch perception is fundamental to melody in music and prosody in speech. Unlike many animals, the vast majority of human adults store melodic information primarily in terms of relative not absolute pitch, and readily recognize a melody whether rendered in a high or a low pitch range. We show that at 6 months infants are also primarily relative…

  10. 14 CFR 23.33 - Propeller speed and pitch limits.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Propeller speed and pitch limits. 23.33 Section 23.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Propeller speed and pitch limits. (a) General. The propeller speed and pitch must be limited to values...

  11. On Older Listeners' Ability to Perceive Dynamic Pitch

    PubMed Central

    Wright, Richard; Souza, Pamela E.

    2016-01-01

    Purpose Natural speech comes with variation in pitch, which serves as an important cue for speech recognition. The present study investigated older listeners' dynamic pitch perception with a focus on interindividual variability. In particular, we asked whether some of the older listeners' inability to perceive dynamic pitch stems from the higher susceptibility to the interference from formant changes. Method A total of 22 older listeners and 21 younger controls with at least near-typical hearing were tested on dynamic pitch identification and discrimination tasks using synthetic monophthong and diphthong vowels. Results The older listeners' ability to detect changes in pitch varied substantially, even when musical and linguistic experiences were controlled. The influence of formant patterns on dynamic pitch perception was evident in both groups of listeners. Overall, strong pitch contours (i.e., more dynamic) were perceived better than weak pitch contours (i.e., more monotonic), particularly with rising pitch patterns. Conclusions The findings are in accordance with the literature demonstrating some older individuals' difficulty perceiving dynamic pitch cues in speech. Moreover, they suggest that this problem may be prominent when the dynamic pitch is carried by natural speech and when the pitch contour is not strong. PMID:27177161

  12. Prosodic Transfer: From Chinese Lexical Tone to English Pitch Accent

    ERIC Educational Resources Information Center

    Ploquin, Marie

    2013-01-01

    Chinese tones are associated with a syllable to convey meaning, English pitch accents are prominence markers associated with stressed syllables. As both are created by pitch modulation, their pitch contours can be quite similar. The experiment reported here examines whether native speakers of Chinese produce, when speaking English, the Chinese…

  13. Dynamic characteristics of peripheral jet ACV. II - Pitching motion

    NASA Astrophysics Data System (ADS)

    Mori, T.; Maeda, H.

    The dynamic pitching characteristics of peripheral jet ACV (Air Cushion Vehicle) which have a stability curtain are investigated analytically and experimentally. The measured values of moment, lift and cushion pressure are compared with numerical results noting applicability to the pitching motion. The response of ACV to the sinusoidal pitching oscillation of the ground is also studied.

  14. Adaptive shoot and root responses collectively enhance growth at optimum temperature and limited phosphorus supply of three herbaceous legume species

    PubMed Central

    Suriyagoda, Lalith D. B.; Ryan, Megan H.; Renton, Michael; Lambers, Hans

    2012-01-01

    Background and Aims Studies on the effects of sub- and/or supraoptimal temperatures on growth and phosphorus (P) nutrition of perennial herbaceous species at growth-limiting P availability are few, and the impacts of temperature on rhizosphere carboxylate dynamics are not known for any species. Methods The effect of three day/night temperature regimes (low, 20/13 °C; medium, 27/20 °C; and high, 32/25 °C) on growth and P nutrition of Cullen cinereum, Kennedia nigricans and Lotus australis was determined. Key Results The highest temperature was optimal for growth of C. cinereum, while the lowest temperature was optimal for K. nigricans and L. australis. At optimum temperatures, the relative growth rate (RGR), root length, root length per leaf area, total P content, P productivity and water-use efficiency were higher for all species, and rhizosphere carboxylate content was higher for K. nigricans and L. australis. Cullen cinereum, with a slower RGR, had long (higher root length per leaf area) and thin roots to enhance P uptake by exploring a greater volume of soil at its optimum temperature, while K. nigricans and L. australis, with faster RGRs, had only long roots (higher root length per leaf area) as a morphological adaptation, but had a higher content of carboxylates in their rhizospheres at the optimum temperature. Irrespective of the species, the amount of P taken up by a plant was mainly determined by root length, rather than by P uptake rate per unit root surface area. Phosphorus productivity was correlated with RGR and plant biomass. Conclusions All three species exhibited adaptive shoot and root traits to enhance growth at their optimum temperatures at growth-limiting P supply. The species with a slower RGR (i.e. C. cinereum) showed only morphological root adaptations, while K. nigricans and L. australis, with faster RGRs, had both morphological and physiological (i.e. root carboxylate dynamics) root adaptations. PMID:22847657

  15. Early processing of pitch in the human auditory system.

    PubMed

    Alho, Kimmo; Grimm, Sabine; Mateo-León, Sabina; Costa-Faidella, Jordi; Escera, Carles

    2012-10-01

    Middle-latency auditory evoked potentials, indicating early cortical processing, elicited by pitch changes and repetitions in pure tones and by complex tones with a missing-fundamental pitch were recorded in healthy adults ignoring the sounds while watching a silenced movie. Both for the pure and for the missing-fundamental tones, the Nb middle-latency response was larger for pitch changes (tones preceded by tones of different pitch) than for pitch repetitions (tones preceded by tones of the same pitch). This Nb enhancement was observed even for missing-fundamental tones preceded by repeated tones that had a different missing-fundamental pitch but included all harmonics of the subsequent tone with another missing-fundamental pitch. This finding rules out the possibility that the Nb enhancement in response to a change in missing-fundamental pitch was simply attributable to the activity of auditory cortex neurons responding specifically to the harmonics of missing-fundamental tones. The Nb effect presumably indicates pitch processing at or near the primary auditory cortex, and it was followed by a change-related enhancement of the N1 response, presumably generated in the secondary auditory cortex. This N1 enhancement might have been caused by a mismatch negativity response overlapping with the N1 response. Processing of missing-fundamental pitch was also reflected by the distribution of Nb responses. Tones with a higher missing-fundamental pitch elicited more frontally dominant Nb responses than tones with a lower missing-fundamental pitch. This effect of pitch, not seen for the pure tones, might indicate that the exact location of the Nb generator source in the auditory cortex depends on the missing-fundamental pitch of the eliciting tone.

  16. Sensitivity of the cortical pitch onset response to height, time-variance, and directionality of dynamic pitch.

    PubMed

    Bidelman, Gavin M

    2015-08-31

    Event-related brain potentials (ERPs) demonstrate that human auditory cortical responses are sensitive to changes in static pitch as indexed by the pitch onset response (POR), a negativity generated at the initiation of acoustic periodicity. Yet, it is still unclear if this brain signature is sensitive to dynamic, time-varying properties of pitch more characteristic of those found in naturalistic speech and music. Neuroelectric PORs were recorded in response to contrastive pitch patterns differing in their pitch height, time-variance, and directionality (i.e., rise vs. fall). Broadband noise followed by contiguous iterated rippled noise (producing salient pitch sweeps) was used to temporally separate neural activity coding the onset of acoustic energy from the onset of time-varying pitch. Analysis of PORs revealed distinct modulations in response latency that distinguished static from time-varying pitch contours (steady-statepitch height (highpitch sweeps (rise=fall). Our findings suggest that the POR signature provides a useful neural index of auditory cortical pitch processing for some, but not all pitch-evoking stimuli.

  17. Boronated mesophase pitch coke for lithium insertion

    NASA Astrophysics Data System (ADS)

    Frackowiak, E.; Machnikowski, J.; Kaczmarska, H.; Béguin, F.

    Boronated carbons from mesophase pitch have been used as materials for lithium storage in Li/carbon cells. Doping by boron has been realized by co-pyrolysis of coal tar pitch with the pyridine-borane complex. Amount of boron in mesocarbon microbeads (MCMB) varied from 1.4 to 1.8 wt.% affecting the texture of carbon. Optical microscopy and X-ray diffractograms have shown tendency to more disordered structure for boron-doped carbon. The values of specific reversible capacity ( x) varied from 0.7 to 1.1 depending significantly on the final temperature of pyrolysis (700-1150°C). The optimal charge/discharge performance was observed for boronated carbon heated at 1000°C.

  18. Stabilization and carbonization of mesophase pitch nanofiber

    NASA Astrophysics Data System (ADS)

    Fong, Hao; Reneker, Darrell H.

    2000-03-01

    Mesophase pitch nanofibers were made with diameters of several hundred nanometers to a few microns. Thermogravimetric analysis showed the stabilization reaction in air began at a temperature below 200^oC, and produced a 6% weight gain. Changes intensity of aliphatic C-H (2850-3000 and 1400-1450 cm-1) and carbonyl -CO- (1690-1750 cm-1) peaks in Fourier transform infrared spectra were observed as a result of stabilization. The intensities of aryl alkyl ether peaks at 1200-1275 cm-1 increased with stabilization in air. Solid state NMR results confirmed these changes. Carbonization in inert gas began when the temperature reached 300^oC. There was a 25% weight loss during the carbonization. Element analysis showed that the only carbon remained. The structures of pitch nanofibers, stabilized nanofibers and the resulting carbon nanofibers were investigated with scanning electron microscopy, transmission electron microscopy and X-ray diffraction.

  19. Biomechanics of the elbow during baseball pitching.

    PubMed

    Werner, S L; Fleisig, G S; Dillman, C J; Andrews, J R

    1993-06-01

    By understanding pitching biomechanics, therapists can develop better preventive and rehabilitative programs for pitchers. The purpose of this study was to quantify and explain the joint motions, loads, and muscle activity that occur at the elbow during baseball pitching. Seven healthy, adult pitchers were examined with synchronized high-speed video digitization and surface electromyography. Elbow extension before ball release corresponded with a decrease in biceps activity and an increase in triceps activity. A varus torque of 120 Nm, acting to resist valgus stress, occurred near the time of maximum shoulder external rotation. Previous cadaveric research showed that the ulnar collateral ligament by itself cannot withstand a valgus load of this magnitude. Triceps, wrist flexorpronator, and anconeus activity during peak valgus stress suggests that these muscles may act as dynamic stabilizers to assist the ulnar collateral ligament in preventing valgus extension overload.

  20. Visual gaze behavior of near-expert and expert fast pitch softball umpires calling a pitch.

    PubMed

    Millslagle, Duane G; Smith, Melissa S; Hines, Bridget B

    2013-05-01

    The purpose of this study was to examine the difference in visual gaze behavior between near expert (NE) and expert (E) umpires in a simulated pitch-hit situation in fast pitch softball. An Applied Science Laboratory mobile eye tracker was worn by 4 NE and 4 E fast pitch umpires and recorded their visual gaze behavior while following pitches (internal view). A digital camera located behind the pitcher recorded the external view of the pitcher, hitter, catcher, and umpire actions for each pitch. The internal and external video clips of 10 representative pitches--5 balls and 5 strikes--were synchronized and displayed in a split screen and were then coded for statistical analyses using Quiet eye solution software. Analysis of variance and multivariate analysis of variance statistical analyses of the umpires' gaze behavior during onset, duration, offset, and frequency (fixation/pursuit tracking, saccades, and blinks) were conducted between and within the 5 stages (pitcher's preparation, delivery and release, ball in flight, and umpire call) by umpire's skill level. Significant differences (p < 0.05) observed for combined gaze behavior frequency, type of gaze by phase, quiet eye duration and onset, and ball duration tracking indicated that E umpires' visual control was more stable and economical than NE umpires. Quiet eye significant results indicated that E umpires had an earlier onset (mean = 50.0 ± 13.9% vs. 56 ± 9.5%) and longer duration (mean = 15.1 ± 11.3% vs. 9.3 ± 6.5%) of the pitcher's release area than NE umpires. These findings suggest that gaze behavior of expert fast pitch umpires was more economical, fixated earlier and for a longer period of time on the area where the ball would be released, and was able to track the ball earlier and for a longer period of time.

  1. Inductance Calculations of Variable Pitch Helical Inductors

    DTIC Science & Technology

    2015-08-01

    Electromagnetic Phenomena. July 2003;3:392–396. 2. Snow C. Formulas for computing capacitance and inductance . In: National bu- reau of standards circular 544...ARL-TR-7380 ● AUG 2015 US Army Research Laboratory Inductance Calculations of Variable Pitch Helical Inductors by Peter T...report when it is no longer needed. Do not return it to the originator. ARL-TR-7380 ● AUG 2015 US Army Research Laboratory Inductance

  2. Estimates of Lifetimes Against Pitch Angle Diffusion

    DTIC Science & Technology

    2008-07-24

    Journal of Atmospheric and Solar - Terrestrial Physics 71 (2009) 1647-1652 Contents lists available at ScienceDirect Journal of Atmospheric and Solar - Terrestrial Physics journal homepage: www.elsevier.com/locate/jastp J "nir5i( >- O O o p O Estimates of lifetimes against pitch angle diffusion J.M. Albert3*, Y.Y. Shpritsb ’Air Force Research Laboratory. Space Vehicles Directorate, 29 Randolph

  3. Pitch-based carbon foam and composites

    DOEpatents

    Klett, James W.

    2002-01-01

    A process for producing carbon foam or a composite is disclosed which obviates the need for conventional oxidative stabilization. The process employs mesophase or isotropic pitch and a simplified process using a single mold. The foam has a relatively uniform distribution of pore sizes and a highly aligned graphic structure in the struts. The foam material can be made into a composite which is useful in high temperature sandwich panels for both thermal and structural applications.

  4. Pitch-based carbon foam and composites

    DOEpatents

    Klett, James W.

    2003-12-02

    A process for producing carbon foam or a composite is disclosed which obviates the need for conventional oxidative stabilization. The process employs mesophase or isotropic pitch and a simplified process using a single mold. The foam has a relatively uniform distribution of pore sizes and a highly aligned graphic structure in the struts. The foam material can be made into a composite which is useful in high temperature sandwich panels for both thermal and structural applications.

  5. Pitch-based carbon foam and composites

    DOEpatents

    Klett, James W.

    2001-01-01

    A process for producing carbon foam or a composite is disclosed which obviates the need for conventional oxidative stabilization. The process employs mesophase or isotropic pitch and a simplified process using a single mold. The foam has a relatively uniform distribution of pore sizes and a highly aligned graphic structure in the struts. The foam material can be made into a composite which is useful in high temperature sandwich panels for both thermal and structural applications.

  6. Pitch-based carbon foam and composites

    DOEpatents

    Klett, James W.

    2003-12-16

    A process for producing carbon foam or a composite is disclosed which obviates the need for conventional oxidative stabilization. The process employs mesophase or isotropic pitch and a simplified process using a single mold. The foam has a relatively uniform distribution of pore sizes and a highly aligned graphic structure in the struts. The foam material can be made into a composite which is useful in high temperature sandwich panels for both thermal and structural applications.

  7. Place-pitch manipulations with cochlear implants

    PubMed Central

    Macherey, Olivier; Carlyon, Robert P.

    2012-01-01

    Pitch can be conveyed to cochlear implant (CI) listeners via both place of excitation and temporal cues. The transmission of place cues may be hampered by several factors including limitations on the insertion depth and number of implanted electrodes, and the broad current spread produced by monopolar stimulation. The following series of experiments investigate several methods to partially overcome these limitations. Experiment 1 compares two recently published techniques that aim to activate more apical fibers than produced by monopolar or bipolar stimulation of the most apical contacts. The first technique (phantom stimulation) manipulates the current spread by simultaneously stimulating two electrodes with opposite-polarity pulses of different amplitudes. The second technique manipulates the neural spread of excitation by using asymmetric pulses and exploiting the polarity-sensitive properties of auditory nerve fibers. The two techniques yielded similar results and were shown to produce lower place pitch percepts than stimulation of monopolar and bipolar symmetric pulses. Furthermore, combining these two techniques may be advantageous in a clinical setting. Experiment 2 proposes a novel method to create place pitches intermediate to those produced by physical electrodes by using charge-balanced asymmetric pulses in bipolar mode with different degrees of asymmetry. PMID:22423718

  8. Individual blade pitch for yaw control

    NASA Astrophysics Data System (ADS)

    Navalkar, S. T.; van Wingerden, J. W.; van Kuik, G. A. M.

    2014-06-01

    Individual pitch control (IPC) for reducing blade loads has been investigated and proven successful in recent literature. For IPC, the multi-blade co-ordinate (MBC) transformation is used to process the blade load signals from the rotating to a stationary frame of reference. In the stationary frame of reference, the yaw error of a turbine can be appended to generate IPC actions that are able to achieve turbine yaw control for a turbine in free yaw. In this paper, IPC for yaw control is tested on a high-fidelity numerical model of a commercially produced wind turbine in free yaw. The tests show that yaw control using IPC has the distinct advantage that the yaw system loads and support structure loading are substantially reduced. However, IPC for yaw control also shows a reduction in IPC blade load reduction potential and causes a slight increase in pitch activity. Thus, the key contribution of this paper is the concept demonstration of IPC for yaw control. Further, using IPC for yaw as a tuning parameter, it is shown how the best trade-off between blade loading, pitch activity and support structure loading can be achieved for wind turbine design.

  9. Flapping propulsion with tip pitch control

    NASA Astrophysics Data System (ADS)

    Huera-Huarte, Francisco; Gharib, Morteza

    2014-11-01

    The effect of flexibility in the propulsion performance and efficiency of oscillating pitching foils has received a large amount of attention in the past years. Scientists have used simplified robotic models that mimic the kinematics of flying and swimming animals, in order to get inspiration to build more efficient engineering systems. Compliance is one of the aspects that has received more attention, as it seems to be a common feature in nature's flyers and swimmers. Active or passive control elements are also common in nature. We will show how thrust generation in a pitching fin, can be greatly affected by controlling the tip pitch motion dynamically and independently of the fin itself. This is in fact a controlled local change of curvature of the end of the fin. A robotic system has been designed in a way that not only flapping amplitudes and frequencies can be controlled, but also the amplitudes and frequencies of the tip and the phase difference between the tip and the fin. We measured thrust forces and the vortex dynamics in the near wake of the system, by using planar DPIV (Digital Particle Image Velocimetry) in a wide variety of flapping situations with tip control. Funding from Spanish Ministry of Science through Grant DPI2012-37904 is gratefully acknowledged.

  10. Dual-Pitch Processing Mechanisms in Primate Auditory Cortex

    PubMed Central

    Bendor, Daniel; Osmanski, Michael S.

    2012-01-01

    Pitch, our perception of how high or low a sound is on a musical scale, is a fundamental perceptual attribute of sounds and is important for both music and speech. After more than a century of research, the exact mechanisms used by the auditory system to extract pitch are still being debated. Theoretically, pitch can be computed using either spectral or temporal acoustic features of a sound. We have investigated how cues derived from the temporal envelope and spectrum of an acoustic signal are used for pitch extraction in the common marmoset (Callithrix jacchus), a vocal primate species, by measuring pitch discrimination behaviorally and examining pitch-selective neuronal responses in auditory cortex. We find that pitch is extracted by marmosets using temporal envelope cues for lower pitch sounds composed of higher-order harmonics, whereas spectral cues are used for higher pitch sounds with lower-order harmonics. Our data support dual-pitch processing mechanisms, originally proposed by psychophysicists based on human studies, whereby pitch is extracted using a combination of temporal envelope and spectral cues. PMID:23152599

  11. A fundamental residue pitch perception bias for tone language speakers

    NASA Astrophysics Data System (ADS)

    Petitti, Elizabeth

    A complex tone composed of only higher-order harmonics typically elicits a pitch percept equivalent to the tone's missing fundamental frequency (f0). When judging the direction of residue pitch change between two such tones, however, listeners may have completely opposite perceptual experiences depending on whether they are biased to perceive changes based on the overall spectrum or the missing f0 (harmonic spacing). Individual differences in residue pitch change judgments are reliable and have been associated with musical experience and functional neuroanatomy. Tone languages put greater pitch processing demands on their speakers than non-tone languages, and we investigated whether these lifelong differences in linguistic pitch processing affect listeners' bias for residue pitch. We asked native tone language speakers and native English speakers to perform a pitch judgment task for two tones with missing fundamental frequencies. Given tone pairs with ambiguous pitch changes, listeners were asked to judge the direction of pitch change, where the direction of their response indicated whether they attended to the overall spectrum (exhibiting a spectral bias) or the missing f0 (exhibiting a fundamental bias). We found that tone language speakers are significantly more likely to perceive pitch changes based on the missing f0 than English speakers. These results suggest that tone-language speakers' privileged experience with linguistic pitch fundamentally tunes their basic auditory processing.

  12. Research on the Development of Baseball Pitching Machine Controlling Pitch Type using Neural Network

    NASA Astrophysics Data System (ADS)

    Sakai, Shinobu; Oda, Juhachi; Yonemura, Shigeru; Kawata, Kengo; Horikawa, Saburo; Yamamoto, Hiroyuki

    The most common commercial pitching machines for baseball are the "arm" type and the "two rollers" type. These machines tend to have certain limitations. In particular, it is very difficult to simultaneously change both ball speed and direction. In addition, some types of pitches, such as the curveball or screwball, are not easily achieved. In this study, we will explain the hardware and software design of a new "intelligent" pitching machine which can pitch repeatedly with selectable speed, direction and ball rotation. The machine has three rollers and the motion of each is independently controlled by a hierarchical neural network. If the ball speed, direction and rotation are given as input data to this network, signals for controlling the three rollers are produced as output data. The results of a throw experiment with the machine that we developed are shown, which has the ability to pitch assorted breaking balls with a wide range of speeds, from 19.4 to 44.4 m/s. The machine has a speed error of less than about 3%, and a distance error of about 0.15m (twice the length of a ball's diameter).

  13. The effect of task and pitch structure on pitch-time interactions in music.

    PubMed

    Prince, Jon B; Schmuckler, Mark A; Thompson, William F

    2009-04-01

    Musical pitch-time relations were explored by investigating the effect of temporal variation on pitch perception. In Experiment 1, trained musicians heard a standard tone followed by a tonal context and then a comparison tone. They then performed one of two tasks. In the cognitive task, they indicated whether the comparison tone was in the key of the context. In the perceptual task, they judged whether the comparison tone was higher or lower than the standard tone. For both tasks, the comparison tone occurred early, on time, or late with respect to temporal expectancies established by the context. Temporal variation did not affect accuracy in either task. Experiment 2 used the perceptual task and varied the pitch structure by employing either a tonal or an atonal context. Temporal variation did not affect accuracy for tonal contexts, but did for atonal contexts. Experiment 3 replicated these results and controlled potential confounds. We argue that tonal contexts bias attention toward pitch and eliminate effects of temporal variation, whereas atonal contexts do not, thus fostering pitch-time interactions.

  14. Evaluation of fluidic thrust vectoring nozzle via thrust pitching angle and thrust pitching moment

    NASA Astrophysics Data System (ADS)

    Li, L.; Hirota, M.; Ouchi, K.; Saito, T.

    2017-01-01

    Shock vector control (SVC) in a converging-diverging nozzle with a rectangular cross-section is discussed as a fluidic thrust vectoring (FTV) method. The interaction between the primary nozzle flow and the secondary jet is examined using experiments and numerical simulations. The relationships between FTV parameters [nozzle pressure ratio (NPR) and secondary jet pressure ratio (SPR)] and FTV performance (thrust pitching angle and thrust pitching moment) are investigated. The experiments are conducted with an NPR of up to 10 and an SPR of up to 2.7. Numerical simulations of the nozzle flow are performed using a Navier-Stokes solver with input parameters set to match the experimental conditions. The thrust pitching angle and moment computed from the force-moment balance are used to evaluate FTV performance. The experiment and numerical results indicate that the FTV parameters (NPR and SPR) directly affect FTV performance. Conventionally, FTV performance evaluated by the common method using thrust pitching angle is highly dependent on the location of evaluation. Hence, in this study, we show that the thrust pitching moment, a parameter which is independent of the location, is the appropriate figure of merit to evaluate the performance of FTV systems.

  15. Training of Working Memory Impacts Neural Processing of Vocal Pitch Regulation

    PubMed Central

    Li, Weifeng; Guo, Zhiqiang; Jones, Jeffery A.; Huang, Xiyan; Chen, Xi; Liu, Peng; Chen, Shaozhen; Liu, Hanjun

    2015-01-01

    Working memory training can improve the performance of tasks that were not trained. Whether auditory-motor integration for voice control can benefit from working memory training, however, remains unclear. The present event-related potential (ERP) study examined the impact of working memory training on the auditory-motor processing of vocal pitch. Trained participants underwent adaptive working memory training using a digit span backwards paradigm, while control participants did not receive any training. Before and after training, both trained and control participants were exposed to frequency-altered auditory feedback while producing vocalizations. After training, trained participants exhibited significantly decreased N1 amplitudes and increased P2 amplitudes in response to pitch errors in voice auditory feedback. In addition, there was a significant positive correlation between the degree of improvement in working memory capacity and the post-pre difference in P2 amplitudes. Training-related changes in the vocal compensation, however, were not observed. There was no systematic change in either vocal or cortical responses for control participants. These findings provide evidence that working memory training impacts the cortical processing of feedback errors in vocal pitch regulation. This enhanced cortical processing may be the result of increased neural efficiency in the detection of pitch errors between the intended and actual feedback. PMID:26553373

  16. Pilot usage of decoupled flight path and pitch controls

    NASA Technical Reports Server (NTRS)

    Berkhout, J.; Osgood, R.; Berry, D.

    1985-01-01

    Data from decoupled flight maneuvers have been collected and analyzed for four AFTI-F-16 pilots operating this aircraft's highly augmented fly-by-wire control system, in order to obtain spectral density, cross spectra, and Bode amplitude data, as well as coherences and phase angles for the two longitudinal axis control functions of each of 50 20-sec epochs. The analysis of each epoch yielded five distinct plotted parameters for the left hand twist grip and right hand sidestick controller output time series. These two control devices allow the left hand to generate vertical translation, direct lift, or pitch-pointing commands that are decoupled from those of the right hand. Attention is given to the control patterns obtained for decoupled normal flight, air-to-air gun engagement decoupled maneuvering, and decoupled air-to-surface bombing run maneuvering.

  17. Reduction of blade-vortex interaction noise using higher harmonic pitch control

    NASA Technical Reports Server (NTRS)

    Brooks, Thomas F.; Booth, Earl R., Jr.; Jolly, J. Ralph, Jr.; Yeager, William T., Jr.; Wilbur, Matthew L.

    1989-01-01

    An acoustics test using an aeroelastically scaled rotor was conducted to examine the effectiveness of higher harmonic blade pitch control for the reduction of impulsive blade-vortex interaction (BVI) noise. A four-bladed, 110 in. diameter, articulated rotor model was tested in a heavy gas (Freon-12) medium in Langley's Transonic Dynamics Tunnel. Noise and vibration measurements were made for a range of matched flight conditions, where prescribed (open-loop) higher harmonic pitch was superimposed on the normal (baseline) collective and cyclic trim pitch. For the inflow-microphone noise measurements, advantage was taken of the reverberance in the hard walled tunnel by using a sound power determination approach. Initial findings from on-line data processing for three of the test microphones are reported for a 4/rev (4P) collective pitch control for a range of input amplitudes and phases. By comparing these results to corresponding baseline (no control) conditions, significant noise reductions (4 to 5 dB) were found for low-speed descent conditions, where helicopter BVI noise is most intense. For other rotor flight conditions, the overall noise was found to increase. All cases show increased vibration levels.

  18. Reduction of blade-vortex interaction noise through higher harmonic pitch control

    NASA Technical Reports Server (NTRS)

    Brooks, Thomas F.; Booth, Earl R., Jr.; Jolly, J. Ralph, Jr.; Yeager, William T., Jr.; Wilbur, Matthew L.

    1990-01-01

    An acoustics test using an aeroelastically scaled rotor was conducted to examine the effectiveness of higher harmonic blade pitch control for the reduction of impulsive blade-vortex interaction (BVI) noise. A four-bladed, 110 in. diameter, articulated rotor model was tested in a heavy gas (Freon-12) medium in Langley's Transonic Dynamics Tunnel. Noise and vibration measurements were made for a range of matched flight conditions, where prescribed (open-loop) higher harmonic pitch was superimposed on the normal (baseline) collective and cyclic trim pitch. For the inflow-microphone noise measurements, advantage was taken of the reverberance in the hard walled tunnel by using a sound power determination approach. Initial findings from on-line data processing for three of the test microphones are reported for a 4/rev (4P) collective pitch control for a range of input amplitudes and phases. By comparing these results to corresponding baseline (no control) conditions, significant noise reductions (4 to 5 dB) were found for low-speed descent conditions, where helicopter BVI noise is most intense. For other rotor flight conditions, the overall noise was found to increase. All cases show increased vibration levels.

  19. A Structural Theory of Pitch1,2,3

    PubMed Central

    Laudanski, Jonathan; Zheng, Yi

    2014-01-01

    Abstract Musical notes can be ordered from low to high along a perceptual dimension called “pitch”. A characteristic property of these sounds is their periodic waveform, and periodicity generally correlates with pitch. Thus, pitch is often described as the perceptual correlate of the periodicity of the sound’s waveform. However, the existence and salience of pitch also depends in a complex way on other factors, in particular harmonic content. For example, periodic sounds made of high-order harmonics tend to have a weaker pitch than those made of low-order harmonics. Here we examine the theoretical proposition that pitch is the perceptual correlate of the regularity structure of the vibration pattern of the basilar membrane, across place and time—a generalization of the traditional view on pitch. While this proposition also attributes pitch to periodic sounds, we show that it predicts differences between resolved and unresolved harmonic complexes and a complex domain of existence of pitch, in agreement with psychophysical experiments. We also present a possible neural mechanism for pitch estimation based on coincidence detection, which does not require long delays, in contrast with standard temporal models of pitch. PMID:26464959

  20. A seamless-pitched graphene nanoribbon field effect transistor

    NASA Astrophysics Data System (ADS)

    Haji-Nasiri, Saeed; Kazem Moravvej-Farshi, Mohammad; Faez, Rahim

    2015-11-01

    This paper proposes a graphene nanoribbon field effect transistor (GNRFET) consisting of pitched semiconducting GNRs as the channels that are connected to the metallic graphene source/drain in a seamless fashion. We obtained the diagrams for frequency bandwidths, step time responses, and Nyquist stability for the seamless pitched GNRFET (SP-GNRFET) with a channel having 100 pitched GNRs at 10 nm pitch in the common source configuration with various dimensions of the GNRs. The aforementioned diagrams were also obtained for the pitched carbon nanotube field effect transistor (CNTFET) with a channel having 100 pitched CNTs at 10 nm pitch in the common source configuration with various dimensions of the CNTs. In order to compare the SP-GNRFET and the pitched CNTFET, physical parameters of the GNRs/CNTs were assumed to be the same in both devices. The results show that when the dimensions of GNRs in the SP-GNRFET increase, the frequency bandwidth decreases, but relaxation time and Nyquist stability increase. Moreover, with an increase in the dimensions of CNTs, similar behavior is observed for the pitched CNTFET. The results also show that the frequency bandwidth of SP-GNRFET is in the range of 10 THz and is more than that of the pitched CNTFET by two orders of magnitude. This is achieved by eliminating the Schottky barrier between the channels and source/drain contacts in the SP-GNRFET. Nevertheless, step time responses for the SP-GNRFET show multi-harmonic oscillations like those for the pitched CNTFET. This shows the importance of stability analysis as a challenge to the SP-GNRFET. Nyquist diagrams predict lower stability for SP-GNRFETs than for pitched CNTFETs. This is because elimination of the Schottky barrier results in a reduction in the overall impedance of the SP-GNRFET, which in turn leads to the frequency of the fluctuations in the SP-GNRFET being more than that in the pitched CNTFET.

  1. Design of the small pixel pitch ROIC

    NASA Astrophysics Data System (ADS)

    Liang, Qinghua; Jiang, Dazhao; Chen, Honglei; Zhai, Yongcheng; Gao, Lei; Ding, Ruijun

    2014-11-01

    Since the technology trend of the third generation IRFPA towards resolution enhancing has steadily progressed,the pixel pitch of IRFPA has been greatly reduced.A 640×512 readout integrated circuit(ROIC) of IRFPA with 15μm pixel pitch is presented in this paper.The 15μm pixel pitch ROIC design will face many challenges.As we all known,the integrating capacitor is a key performance parameter when considering pixel area,charge capacity and dynamic range,so we adopt the effective method of 2 by 2 pixels sharing an integrating capacitor to solve this problem.The input unit cell architecture will contain two paralleled sample and hold parts,which not only allow the FPA to be operated in full frame snapshot mode but also save relatively unit circuit area.Different applications need more matching input unit circuits. Because the dimension of 2×2 pixels is 30μm×30μm, an input stage based on direct injection (DI) which has medium injection ratio and small layout area is proved to be suitable for middle wave (MW) while BDI with three-transistor cascode amplifier for long wave(LW). By adopting the 0.35μm 2P4M mixed signal process, the circuit architecture can make the effective charge capacity of 7.8Me- per pixel with 2.2V output range for MW and 7.3 Me- per pixel with 2.6V output range for LW. According to the simulation results, this circuit works well under 5V power supply and achieves less than 0.1% nonlinearity.

  2. How to pitch a brilliant idea.

    PubMed

    Elsbach, Kimberly D

    2003-09-01

    Coming up with creative ideas is easy; selling them to strangers is hard. Entrepreneurs, sales executives, and marketing managers often go to great lengths to demonstrate how their new concepts are practical and profitable--only to be rejected by corporate decision makers who don't seem to understand the value of the ideas. Why does this happen? Having studied Hollywood executives who assess screenplay pitches, the author says the person on the receiving end--the "catcher"--tends to gauge the pitcher's creativity as well as the proposal itself. An impression of the pitcher's ability to come up with workable ideas can quickly and permanently overshadow the catcher's feelings about an idea's worth. To determine whether these observations apply to business settings beyond Hollywood, the author attended product design, marketing, and venture-capital pitch sessions and conducted interviews with executives responsible for judging new ideas. The results in those environments were similar to her observations in Hollywood, she says. Catchers subconsciously categorize successful pitchers as showrunners (smooth and professional), artists (quirky and unpolished), or neophytes (inexperienced and naive). The research also reveals that catchers tend to respond well when they believe they are participating in an idea's development. As Oscar-winning writer, director, and producer Oliver Stone puts it, screen-writers pitching an idea should "pull back and project what he needs onto your idea in order to make the story whole for him." To become a successful pitcher, portray yourself as one of the three creative types and engage your catchers in the creative process. By finding ways to give your catchers a chance to shine, you sell yourself as a likable collaborator.

  3. Development of a Passively Varying Pitch Propeller

    NASA Astrophysics Data System (ADS)

    Heinzen, Stearns Beamon

    Small general aviation aircraft and unmanned aerial systems are often equipped with sophisticated navigation, control, and other avionics, but retain propulsion systems consisting of retrofitted radio control and ultralight equipment. Consequently, new high performance airframes often rely on relatively primitive propulsive technology. This trend is beginning to shift with recent advances in small turboprop engines, fuel injected reciprocating engines, and improved electric technologies. Although these systems are technologically advanced, they are often paired with standard fixed pitch propellers. To fully realize the potential of these aircraft and the new generation of engines, small propellers which can efficiently transmit power over wide flight envelopes and a variety of power settings must be developed. This work demonstrates a propeller which passively adjusts to incoming airflow at a low penalty to aircraft weight and complexity. This allows the propeller to operate in an efficient configuration over a wide flight envelope, and can prevent blade stall in low-velocity / highly-loaded thrust cases and over-speeding at high flight speeds. The propeller incorporates blades which pivot freely on a radial axis and are aerodynamically tailored to attain and maintain a pitch angle yielding favorable local blade angles of attack, matched to changing inflow conditions. This blade angle is achieved through the use of reflexed airfoils designed for a positive pitching moment, comparable to those used on many tailless flying wings. By setting the axis of rotation at a point forward of the blade aerodynamic center, the blades will naturally adjust to a predetermined positive lift 'trim' condition. Then, as inflow conditions change, the blade angle will automatically pivot to maintain the same angle with respect to incoming air. Computational, wind tunnel, and flight test results indicate that the extent of efficient propeller operation can be increased dramatically as

  4. Higher harmonic rotor blade pitch control

    NASA Technical Reports Server (NTRS)

    Ewans, J. R.

    1976-01-01

    Tests of a model 'Reverse Velocity Rotor' system at high advance ratios and with twice-per-revolution cyclic pitch control were made under joint Navy-NASA sponsorship in the NASA, Ames 12 ft. pressure tunnel. The results showed significant gains in rotor performance at all advance ratios by using twice-per-revolution control. Detailed design studies have been made of alternative methods of providing higher harmonic motion including four types of mechanical systems and an electro-hydraulic system. The relative advantages and disadvantages are evaluated on the basis of stiffness, weight, volume, reliability and maintainability.

  5. Left-hemisphere activation is associated with enhanced vocal pitch error detection in musicians with absolute pitch

    PubMed Central

    Behroozmand, Roozbeh; Ibrahim, Nadine; Korzyukov, Oleg; Robin, Donald A.; Larson, Charles R.

    2014-01-01

    The ability to process auditory feedback for vocal pitch control is crucial during speaking and singing. Previous studies have suggested that musicians with absolute pitch (AP) develop specialized left-hemisphere mechanisms for pitch processing. The present study adopted an auditory feedback pitch perturbation paradigm combined with ERP recordings to test the hypothesis whether the neural mechanisms of the left-hemisphere enhance vocal pitch error detection and control in AP musicians compared with relative pitch (RP) musicians and non-musicians (NM). Results showed a stronger N1 response to pitch-shifted voice feedback in the right-hemisphere for both AP and RP musicians compared with the NM group. However, the left-hemisphere P2 component activation was greater in AP and RP musicians compared with NMs and also for the AP compared with RP musicians. The NM group was slower in generating compensatory vocal reactions to feedback pitch perturbation compared with musicians, and they failed to re-adjust their vocal pitch after the feedback perturbation was removed. These findings suggest that in the earlier stages of cortical neural processing, the right hemisphere is more active in musicians for detecting pitch changes in voice feedback. In the later stages, the left-hemisphere is more active during the processing of auditory feedback for vocal motor control and seems to involve specialized mechanisms that facilitate pitch processing in the AP compared with RP musicians. These findings indicate that the left hemisphere mechanisms of AP ability are associated with improved auditory feedback pitch processing during vocal pitch control in tasks such as speaking or singing. PMID:24355545

  6. Computationally Inexpensive Approach for Pitch Control of Offshore Wind Turbine on Barge Floating Platform

    PubMed Central

    Zuo, Shan; Song, Y. D.; Wang, Lei; Song, Qing-wang

    2013-01-01

    Offshore floating wind turbine (OFWT) has gained increasing attention during the past decade because of the offshore high-quality wind power and complex load environment. The control system is a tradeoff between power tracking and fatigue load reduction in the above-rated wind speed area. In allusion to the external disturbances and uncertain system parameters of OFWT due to the proximity to load centers and strong wave coupling, this paper proposes a computationally inexpensive robust adaptive control approach with memory-based compensation for blade pitch control. The method is tested and compared with a baseline controller and a conventional individual blade pitch controller with the “NREL offshore 5 MW baseline wind turbine” being mounted on a barge platform run on FAST and Matlab/Simulink, operating in the above-rated condition. It is shown that the advanced control approach is not only robust to complex wind and wave disturbances but adaptive to varying and uncertain system parameters as well. The simulation results demonstrate that the proposed method performs better in reducing power fluctuations, fatigue loads and platform vibration as compared to the conventional individual blade pitch control. PMID:24453834

  7. Computationally inexpensive approach for pitch control of offshore wind turbine on barge floating platform.

    PubMed

    Zuo, Shan; Song, Y D; Wang, Lei; Song, Qing-wang

    2013-01-01

    Offshore floating wind turbine (OFWT) has gained increasing attention during the past decade because of the offshore high-quality wind power and complex load environment. The control system is a tradeoff between power tracking and fatigue load reduction in the above-rated wind speed area. In allusion to the external disturbances and uncertain system parameters of OFWT due to the proximity to load centers and strong wave coupling, this paper proposes a computationally inexpensive robust adaptive control approach with memory-based compensation for blade pitch control. The method is tested and compared with a baseline controller and a conventional individual blade pitch controller with the "NREL offshore 5 MW baseline wind turbine" being mounted on a barge platform run on FAST and Matlab/Simulink, operating in the above-rated condition. It is shown that the advanced control approach is not only robust to complex wind and wave disturbances but adaptive to varying and uncertain system parameters as well. The simulation results demonstrate that the proposed method performs better in reducing power fluctuations, fatigue loads and platform vibration as compared to the conventional individual blade pitch control.

  8. A developmental study of latent absolute pitch memory.

    PubMed

    Jakubowski, Kelly; Müllensiefen, Daniel; Stewart, Lauren

    2017-03-01

    The ability to recall the absolute pitch level of familiar music (latent absolute pitch memory) is widespread in adults, in contrast to the rare ability to label single pitches without a reference tone (overt absolute pitch memory). The present research investigated the developmental profile of latent absolute pitch (AP) memory and explored individual differences related to this ability. In two experiments, 288 children from 4 to12 years of age performed significantly above chance at recognizing the absolute pitch level of familiar melodies. No age-related improvement or decline, nor effects of musical training, gender, or familiarity with the stimuli were found in regard to latent AP task performance. These findings suggest that latent AP memory is a stable ability that is developed from as early as age 4 and persists into adulthood.

  9. Virtual pitch extraction from harmonic structures by absolute-pitch musicians

    NASA Astrophysics Data System (ADS)

    Hsieh, I.-Hui; Saberi, Kourosh

    2009-03-01

    The ability of absolute-pitch (AP) musicians to identify or produce virtual pitch from harmonic structures without feedback or an external acoustic referent was examined in three experiments. Stimuli consisted of pure tones, missing-fundamental harmonic complexes, or piano notes highpass filtered to remove their fundamental frequency and lower harmonics. Results of Experiment I showed that relative to control (non-AP) musicians, AP subjects easily (>90%) identified pitch of harmonic complexes in a 12-alternative forced-choice task. Increasing harmonic order (i.e., lowest harmonic number in the complex), however, resulted in a monotonic decline in performance. Results suggest that AP musicians use two pitch cues from harmonic structures: 1) spectral spacing between harmonic components, and 2) octave-related cues to note identification in individually resolved harmonics. Results of Experiment II showed that highpass filtered piano notes are identified by AP subjects at better than 75% accuracy even when the note’s energy is confined to the 4th and higher harmonics. Identification of highpass piano notes also appears to be better than that expected from pure or complex tones, possibly due to contributions from familiar timbre cues to note identity. Results of Experiment III showed that AP subjects can adjust the spectral spacing between harmonics of a missing-fundamental complex to accurately match the expected spacing from a target musical note. Implications of these findings for mechanisms of AP encoding are discussed.

  10. Nanocal calibration and pitch recertification of a Hitachi microscale standard

    NASA Astrophysics Data System (ADS)

    Yeremin, Dmitry; Nikitin, Arkady; Sicignano, Al; Sandy, Matt; Goldburt, Tim; Tracy, Bryan

    2004-05-01

    The pitch of a Hitachi Standard Micro Scale was measured using NanoCal and a LEO 1560 SEM. The pitch pedigree and certification were intentionally withheld from Nanometrology team members to enable independent measurement and certification of an unknown Hitachi Micro Scale standard during this work. NanoCal allows one to achieve pitch measurements with sub-nanometer accuracy and precision as well as to perform SEM magnification calibration with the precision and accuracy required for sub 90 nm SEM metrology.

  11. Consonantal perturbations of pitch in Halkomelem Salish

    NASA Astrophysics Data System (ADS)

    Brown, Jason; Thompson, James J.

    2005-04-01

    It has long been noted that consonants have an effect on the pitch of a following vowel: voiceless stops tend to raise F0, while voiced stops lower it. It has also been suggested that the duration of such perturbations is shorter in tone languages than in non-tone languages [Hombert, Studies in African Linguistics (1977)]. This study compares the effects that consonants have on F0 in two closely related Salish languages: Island Halkomelem, a non-tone language, and Upriver Halkomelem, a language that has reportedly undergone some limited tonogenesis but offers no clear prosodic clues regarding tonality. The effects of the voiceless and ejective stop series were observed, and measurements of F0 were taken at the onset of voicing for the vowel, then at 20 msec. intervals up to 100 msec. Preliminary results indicate that i) Island Halkomelem shows a greater magnitude of difference in F0 at vowel onset between the voiceless and ejective stops than Upriver Halkomelem, and ii) Island Halkomelem shows greater durations of consonantal perturbations of F0 than does Upriver Halkomelem. This suggests that Upriver Halkomelem may have become more sensitive to pitch than the Island dialect, supporting the interpretation of this language as tonal. [Work supported by Phillips Fund.

  12. Mesophase from anthracene oil-based pitches

    SciTech Connect

    P. Alvarez; J. Sutil; R. Santamaria; C. Blanco; R. Menendez; M. Granda

    2008-11-15

    This work deals with the preparation of the mesophase from two pitch-like materials obtained from anthracene oil by oxidative thermal condensation (AOP-1) and the subsequent thermal treatment and distillation of AOP-1 (AOP-2). The mesophase was obtained by the controlled pyrolysis (440-470{degree}C and different periods of residence times) and subsequent sedimentation of the samples. In the case of the pitch prepared by oxidative thermal condensation, a dynamic pressure of 5 bar was applied during the pyrolysis. The pressure was a critical parameter, and its influence was also investigated. The results show that AOP-1 requires higher temperatures and/or residence times to develop mesophase than AOP-2. After sedimentation, a sample consisting of mainly mesophase was produced in all of the cases. The characterization of the mesophases by means of techniques, such as elemental and thermogravimetric analysis and optical microscopy, showed that anthracene oil-based derivatives are appropriate precursors for producing QI-free mesophase with suitable properties for the fabrication of a wide range of carbon materials. 26 refs., 5 figs., 3 tabs.

  13. A new nonlinear model for pitch perception

    NASA Astrophysics Data System (ADS)

    Cartwright, Julyan H. E.; González, Diego L.; Piro, Oreste

    The ability of the auditory system to perceive the fundamental frequency of a sound even when this frequency is removed from the stimulus is an interesting phenomenon related to the pitch of complex sounds. This capability is known as residue or virtual pitch perception and was first reported last century in the pioneering work of Seebeck. It is residue perception that allows one to listen to music with small transistor radios, which in general have a very poor and sometimes negligible response to low frequencies. The first attempt, due to von Helmholtz, to explain the residue as a nonlinear effect in the ear considered it to originate from difference combination tones. But later experiments showed that the residue does not coincide with a difference combination tone, and nonlinear theories were abandoned. However, in this paper we use recent results from the theory of nonlinear dynamical systems to show that physical frequencies produced by generic nonlinear oscillators acted upon by two independent periodic excitations can reproduce with great precision most of the experimental data about the residue.

  14. Pitch Correlogram Clustering for Fast Speaker Identification

    NASA Astrophysics Data System (ADS)

    Jhanwar, Nitin; Raina, Ajay K.

    2004-12-01

    Gaussian mixture models (GMMs) are commonly used in text-independent speaker identification systems. However, for large speaker databases, their high computational run-time limits their use in online or real-time speaker identification situations. Two-stage identification systems, in which the database is partitioned into clusters based on some proximity criteria and only a single-cluster GMM is run in every test, have been suggested in literature to speed up the identification process. However, most clustering algorithms used have shown limited success, apparently because the clustering and GMM feature spaces used are derived from similar speech characteristics. This paper presents a new clustering approach based on the concept of a pitch correlogram that captures frame-to-frame pitch variations of a speaker rather than short-time spectral characteristics like cepstral coefficient, spectral slopes, and so forth. The effectiveness of this two-stage identification process is demonstrated on the IVIE corpus of 110 speakers. The overall system achieves a run-time advantage of 500% as well as a 10% reduction of error in overall speaker identification.

  15. Nanofiber Anisotropic Conductive Films (ACF) for Ultra-Fine-Pitch Chip-on-Glass (COG) Interconnections

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Hoon; Kim, Tae-Wan; Suk, Kyung-Lim; Paik, Kyung-Wook

    2015-11-01

    Nanofiber anisotropic conductive films (ACF) were invented, by adapting nanofiber technology to ACF materials, to overcome the limitations of ultra-fine-pitch interconnection packaging, i.e. shorts and open circuits as a result of the narrow space between bumps and electrodes. For nanofiber ACF, poly(vinylidene fluoride) (PVDF) and poly(butylene succinate) (PBS) polymers were used as nanofiber polymer materials. For PVDF and PBS nanofiber ACF, conductive particles of diameter 3.5 μm were incorporated into nanofibers by electrospinning. In ultra-fine-pitch chip-on-glass assembly, insulation was significantly improved by using nanofiber ACF, because nanofibers inside the ACF suppressed the mobility of conductive particles, preventing them from flowing out during the bonding process. Capture of conductive particles was increased from 31% (conventional ACF) to 65%, and stable electrical properties and reliability were achieved by use of nanofiber ACF.

  16. Automatic pitching scene archiving system for video indexing support

    NASA Astrophysics Data System (ADS)

    Shono, Yuki; Aoki, Yoshimitsu

    2004-10-01

    A content-based scene indexing has been important technique for an effective video contents handling such as scene retrieval and editing. The standard multimedia content descriptor (MPEG7) has been proposed for the key scene indexing. As for an automatic scene indexing, audio-visual features are most important clues. Many methods have been proposed for effective scene indexing based on those features. In this paper, we propose an automatic key scene detection method for baseball video contents using video features. We regard pitching scenes as key scenes, because they are starting points of all baseball play scenes. If the pitching scenes are detected, they could be effective hints to detect other scenes. In addition, a pitching scene digest video can be easily edited by gathering automatically extracted scenes. The pitching scene digest can be useful data for pitching analysis. We extract pitching scenes using color, domain and motion template created from manually selected pitching scene samples. Those templates contain image features unique to pitching scenes. Template matching is applied to video stream, so that target scenes can be detected by judging calculated matching rate. We experimentally test our method for actual baseball video contents. It can be useful data for pitching analysis and editing of digest news broad casting. We are developing the video indexing support system which users can give text annotations to indexed scenes using MPEG7 format descriptors.

  17. Language experience enhances early cortical pitch-dependent responses

    PubMed Central

    Krishnan, Ananthanarayan; Gandour, Jackson T.; Ananthakrishnan, Saradha; Vijayaraghavan, Venkatakrishnan

    2014-01-01

    Pitch processing at cortical and subcortical stages of processing is shaped by language experience. We recently demonstrated that specific components of the cortical pitch response (CPR) index the more rapidly-changing portions of the high rising Tone 2 of Mandarin Chinese, in addition to marking pitch onset and sound offset. In this study, we examine how language experience (Mandarin vs. English) shapes the processing of different temporal attributes of pitch reflected in the CPR components using stimuli representative of within-category variants of Tone 2. Results showed that the magnitude of CPR components (Na-Pb and Pb-Nb) and the correlation between these two components and pitch acceleration were stronger for the Chinese listeners compared to English listeners for stimuli that fell within the range of Tone 2 citation forms. Discriminant function analysis revealed that the Na-Pb component was more than twice as important as Pb-Nb in grouping listeners by language affiliation. In addition, a stronger stimulus-dependent, rightward asymmetry was observed for the Chinese group at the temporal, but not frontal, electrode sites. This finding may reflect selective recruitment of experience-dependent, pitch-specific mechanisms in right auditory cortex to extract more complex, time-varying pitch patterns. Taken together, these findings suggest that long-term language experience shapes early sensory level processing of pitch in the auditory cortex, and that the sensitivity of the CPR may vary depending on the relative linguistic importance of specific temporal attributes of dynamic pitch. PMID:25506127

  18. Pitch discrimination associated with phonological awareness: Evidence from congenital amusia

    PubMed Central

    Sun, Yanan; Lu, Xuejing; Ho, Hao Tam; Thompson, William Forde

    2017-01-01

    Research suggests that musical skills are associated with phonological abilities. To further investigate this association, we examined whether phonological impairments are evident in individuals with poor music abilities. Twenty individuals with congenital amusia and 20 matched controls were assessed on a pure-tone pitch discrimination task, a rhythm discrimination task, and four phonological tests. Amusic participants showed deficits in discriminating pitch and discriminating rhythmic patterns that involve a regular beat. At a group level, these individuals performed similarly to controls on all phonological tests. However, eight amusics with severe pitch impairment, as identified by the pitch discrimination task, exhibited significantly worse performance than all other participants in phonological awareness. A hierarchical regression analysis indicated that pitch discrimination thresholds predicted phonological awareness beyond that predicted by phonological short-term memory and rhythm discrimination. In contrast, our rhythm discrimination task did not predict phonological awareness beyond that predicted by pitch discrimination thresholds. These findings suggest that accurate pitch discrimination is critical for phonological processing. We propose that deficits in early-stage pitch discrimination may be associated with impaired phonological awareness and we discuss the shared role of pitch discrimination for processing music and speech. PMID:28287166

  19. Clinically Paired Electrodes Are Often Not Perceived as Pitch Matched

    PubMed Central

    Padilla, Monica; Stelmach, Julia; Landsberger, David M.

    2016-01-01

    For bilateral cochlear implant (CI) patients, electrodes that receive the same frequency allocation often stimulate locations in the left and right ear that do not yield the same perceived pitch, resulting in a pitch mismatch. This pitch mismatch may be related to degraded binaural abilities. Pitch mismatches have been found for some bilateral CI users and the goal of this study was to determine whether pitch mismatches are prevalent in bilateral CI patients, including those with extensive experience with bilateral CIs. To investigate this possibility, pitch matching was conducted with 16 bilateral CI patients. For 14 of the 16 participants, there was a significant difference between those electrodes in the left and right ear that yielded the same pitch and those that received the same frequency allocation in the participant’s clinical map. The results suggest that pitch mismatches are prevalent with bilateral CI users. The results also indicated that pitch mismatches persist even with extended bilateral CI experience. Such mismatches may reduce the benefits patients receive from bilateral CIs. PMID:27641682

  20. Comparison of electroglottographic and acoustic analysis of pitch perturbation.

    PubMed

    LaBlance, G R; Maves, M D; Scialfa, T M; Eitnier, C M; Steckol, K F

    1992-11-01

    Pitch perturbation is a measure of the cycle-to-cycle variation in vocal fold vibration. Perturbation can be assessed by means of electroglottographic or acoustic signals. The purpose of this study was to determine if these two analysis techniques are equivalent measures. The Laryngograph, an electroglottograph, and the Visi-Pitch, an acoustic analyzer, were used to measure pitch perturbation in 80 dysphonic subjects. Both instruments use Koike's formula to calculate relative average perturbation. While intra-subject variability appeared erratic, statistical analysis of intersubject data indicated that the two instruments provided an equivalent measure of pitch perturbation.

  1. Impaired short-term memory for pitch in congenital amusia.

    PubMed

    Tillmann, Barbara; Lévêque, Yohana; Fornoni, Lesly; Albouy, Philippe; Caclin, Anne

    2016-06-01

    Congenital amusia is a neuro-developmental disorder of music perception and production. The hypothesis is that the musical deficits arise from altered pitch processing, with impairments in pitch discrimination (i.e., pitch change detection, pitch direction discrimination and identification) and short-term memory. The present review article focuses on the deficit of short-term memory for pitch. Overall, the data discussed here suggest impairments at each level of processing in short-term memory tasks; starting with the encoding of the pitch information and the creation of the adequate memory trace, the retention of the pitch traces over time as well as the recollection and comparison of the stored information with newly incoming information. These impairments have been related to altered brain responses in a distributed fronto-temporal network, associated with decreased connectivity between these structures, as well as in abnormalities in the connectivity between the two auditory cortices. In contrast, amusic participants׳ short-term memory abilities for verbal material are preserved. These findings show that short-term memory deficits in congenital amusia are specific to pitch, suggesting a pitch-memory system that is, at least partly, separated from verbal memory. This article is part of a Special Issue entitled SI: Auditory working memory.

  2. Carbamazepine induced pitch shift and octave space representation.

    PubMed

    Braun, Martin; Chaloupka, Vladimir

    2005-12-01

    Octave-circular pitch perception, the repetition of pitch scale qualities when surpassing the octave interval, has been observed in behavioral data from humans and monkeys, but the underlying anatomy and physiology is still unknown. Here we analyze octave circularity in a concert pianist with absolute pitch, both under medication with the neurotropic drug carbamazepine (CBZ) and without medication. Analysis of 4619 responses in a pitch identification task revealed an internal tone-scale representation, based on the norm-tone scale re A4=440 Hz, with an octave-circular pattern of strongly and weakly represented tones. CBZ caused a global down-shift of pitch (ca. 1 semitone at 500 Hz), but no down-shift of the octave-circular pattern of tone characteristics. This pattern was similar in the six tested octave ranges (32.7-2093 Hz), both under the control and the CBZ condition. Pattern repetition always occurred at octave intervals and did not reflect the stretched octaves of piano tuning. The results indicate that CBZ influences pitch detection peripheral of an octave-circular pitch representation. Thus they support previous evidence for pitch detection in the auditory midbrain and for octave-circular pitch mapping in the auditory thalamus.

  3. The influence of music-elicited emotions and relative pitch on absolute pitch memory for familiar melodies.

    PubMed

    Jakubowski, Kelly; Müllensiefen, Daniel

    2013-01-01

    Levitin's findings that nonmusicians could produce from memory the absolute pitches of self-selected pop songs have been widely cited in the music psychology literature. These findings suggest that latent absolute pitch (AP) memory may be a more widespread trait within the population than traditional AP labelling ability. However, it has been left unclear what factors may facilitate absolute pitch retention for familiar pieces of music. The aim of the present paper was to investigate factors that may contribute to latent AP memory using Levitin's sung production paradigm for AP memory and comparing results to the outcomes of a pitch labelling task, a relative pitch memory test, measures of music-induced emotions, and various measures of participants' musical backgrounds. Our results suggest that relative pitch memory and the quality and degree of music-elicited emotions impact on latent AP memory.

  4. Influence of pitch on the morphology and luminescence properties of self-catalyzed GaAsSb nanowire arrays

    NASA Astrophysics Data System (ADS)

    Ren, Dingding; Huh, Junghwan; Dheeraj, Dasa L.; Weman, Helge; Fimland, Bjørn-Ove

    2016-12-01

    We report on the influence of hole pattern pitch lengths in the silicon oxide mask and specific nanowire (NW) locations on the morphology and luminescence properties of self-catalyzed GaAsSb NW arrays grown by molecular beam epitaxy. Due to stronger competition for the limited amount of Ga adatoms, the GaAsSb NWs in the center of arrays with short pitch lengths possess a smaller catalyst droplet contact angle than that of the NWs at the array edge. This smaller contact angle leads to a reduction in the collection of group V flux, bringing about shorter NWs in the center. For pitch lengths beyond the diffusion length of Ga adatoms on the mask, the GaAsSb NWs are taller with larger contact angles than in the case with short pitch lengths. Considering that Sb has a longer diffusion length on the side facets of the NWs than that of As, a reduction/increase of the contact angle will bring about an increase/reduction in the Sb/As ratio of the group-V fluxes collected by the catalyst droplets. By performing micro-photoluminescence (μ-PL) measurements on the GaAsSb NW arrays at the center of the array for different pitch lengths, a red shift of the μ-PL spectra was found with a decrease in pitch length. Our findings demonstrate that the Ga diffusion-induced contact angle difference is the main cause for the variations in NW morphology and composition with different pitch lengths and NW locations in the array, which provides guidance to optimize the design of NW array devices for advanced optoelectronic applications.

  5. Supercritical fractionation of petroleum pitches: Experiment and prediction

    NASA Astrophysics Data System (ADS)

    Zhuang, Shuzhong

    Previous work at Clemson has shown that supercritical extraction (SCE) can be used to produce liquid crystalline (i.e., mesophase) pitches of excellent quality for use as starting materials for high-performance carbon products. However, to date the full potential of such extraction processes for manipulating the molecular composition of pitches for a desired end use has yet to be realized. The goals of this project were twofold: (1) to develop equations of state (EoSs) applicable to pitch-solvent systems and to the multicomponent pitch mixtures themselves; (2) to investigate the potential of stagewise SCE for producing fractions suitable for analytical characterization studies. A thermodynamic model that incorporates the SAFT EoS, the MWD of the feed pitch, and mathematically generated pseudocomponents was developed for predicting phase compositions and extraction yields for the SCE process. Our model uses two binary parameters, which were determined by fitting a limited set of isothermal LLE data for pitch-solvent systems. SAFT was subsequently used with these parameters to successfully predict solvent-phase compositions at other extraction conditions. As originally developed, SAFT cannot predict the existence of mesophase. Thus, in collaboration with Hurt and co-workers at Brown University, we created a modification of SAFT for these liquid crystalline pitches (i.e., SAFT-LC). Using only three binary parameters, SAFT-LC was successfully used to model both the SCE step, where solvent-pitch interactions dominate, and the mesophase formation step in the dried pitch product, where pitch-pitch interactions are significant. A stagewise fractionation technique employing sequential, single-stage SCE was used to fractionate the heaviest portion of a petroleum pitch by operating at higher pressures in the LLE region. The pressure was sequentially reduced in each stage so as to precipitate out ˜5 wt % of the feed pitch in each stage. Five fractions comprising the heaviest

  6. Subcortical Plasticity Following Perceptual Learning in a Pitch Discrimination Task

    PubMed Central

    Plack, Christopher J.

    2010-01-01

    Practice can lead to dramatic improvements in the discrimination of auditory stimuli. In this study, we investigated changes of the frequency-following response (FFR), a subcortical component of the auditory evoked potentials, after a period of pitch discrimination training. Twenty-seven adult listeners were trained for 10 h on a pitch discrimination task using one of three different complex tone stimuli. One had a static pitch contour, one had a rising pitch contour, and one had a falling pitch contour. Behavioral measures of pitch discrimination and FFRs for all the stimuli were measured before and after the training phase for these participants, as well as for an untrained control group (n = 12). Trained participants showed significant improvements in pitch discrimination compared to the control group for all three trained stimuli. These improvements were partly specific for stimuli with the same pitch modulation (dynamic vs. static) and with the same pitch trajectory (rising vs. falling) as the trained stimulus. Also, the robustness of FFR neural phase locking to the sound envelope increased significantly more in trained participants compared to the control group for the static and rising contour, but not for the falling contour. Changes in FFR strength were partly specific for stimuli with the same pitch modulation (dynamic vs. static) of the trained stimulus. Changes in FFR strength, however, were not specific for stimuli with the same pitch trajectory (rising vs. falling) as the trained stimulus. These findings indicate that even relatively low-level processes in the mature auditory system are subject to experience-related change. PMID:20878201

  7. The Kinetic Chain in Overhand Pitching

    PubMed Central

    Seroyer, Shane T.; Nho, Shane J.; Bach, Bernard R.; Bush-Joseph, Charles A.; Nicholson, Gregory P.; Romeo, Anthony A.

    2010-01-01

    The overhead throwing motion is a coordinated effort of muscle units from the entire body, culminating with explosive motion of the upper extremity. The throwing motion occurs at a rapid pace, making analysis difficult in real time. Electromyographic studies and high-speed video recordings have provided invaluable details regarding the involved musculature, the sequence of muscle involvement, and associated kinematic variables. The goal of the present article is to provide an overview of the kinetic chain—that is, a detailed description of the muscular coordination during each phase of pitching—and to describe specific types of pitches. An enhanced understanding of the components of the kinetic chain and the phases of the throwing motion can provide important information for rehabilitation, performance enhancement, and injury prevention. PMID:23015931

  8. Performance characteristics of pitching flexible foil propulsors

    NASA Astrophysics Data System (ADS)

    Brownell, Cody; Egan, Brendan; Murray, Mark

    2014-11-01

    Performance characteristics of flexible foil propulsors are studied experimentally. The project investigates the dependence of thrust and efficiency on foil elasticity, Strouhal number, and flow velocity. The experiments took place in a large recirculating water channel, using full span flexible propulsor models to approximate a 2D geometry. The propulsor pitched about a fixed axis at its quarter chord, with a six-axis load cell measuring the forces and torques on the shaft. Propulsive efficiency is found to peak at an optimum Strouhal number for each foil tested. Varying elasticity did not produce a similar local maximum over the sampled parameter space. The ensemble data will facilitate the engineering of fish-like propulsion systems for future application of this technology.

  9. Timing of pitch movements and accentuation of syllables in Dutch.

    PubMed

    Hermes, D J

    1997-10-01

    In this study, the relation between the timing of a rising or falling pitch movement and the syllable it accentuates is investigated. The five-syllable utterance /mamamamama/ was provided with a relatively fast rising or falling pitch movement. The timing of the movement was systematically varied and Dutch subjects were asked to indicate which syllable they perceived as accented. In order to find out where in the pitch movement the cue which induces the percept of accentuation is located, the duration of the pitch movement was varied. In order to find out which segments of the utterance this characteristic is linked to, the duration of the /m/ was varied. The results showed that the percept of accentuation is induced by a change in pitch at the start of the movement. The moment at which the course of pitch starts to change significantly determines which syllable is perceived as accented. If this moment lies some tens of milliseconds before the P-center, i.e., the perceptual moment of occurrence of the syllable, the preceding syllable is perceived as accented. For a rise, a high accent is perceived; for a fall, a low accent. If the pitch change occurs after this moment, the syllable with this P-center is perceived as accented. For the rise, a low accent is then perceived; for the fall, a high accent. This will be discussed in the light of earlier research on accentuation and of theoretical knowledge about pitch accents.

  10. The relationship between tinnitus pitch and the audiogram.

    PubMed

    Pan, Tao; Tyler, Richard S; Ji, Haihong; Coelho, Claudia; Gehringer, Anne K; Gogel, Stephanie A

    2009-05-01

    We studied the relationship between tinnitus pitch and the audiogram in 195 patients. Patients with tone-like tinnitus reported a higher pitch (mean = 5385 Hz) compared to those with a noise-like quality (mean = 3266 Hz). Those with a flat audiogram were more likely to report: a noise-like tinnitus, a unilateral tinnitus, and have a pitch < 2000 Hz. The average duration of bilateral tinnitus (12 years) was longer than that of unilateral tinnitus (5 years). Older subjects reported a less severe tinnitus handicap questionnaire score. Patients with a notched audiogram often reported a pitch pitch >or=8000 Hz. We failed to find a relationship between the pitch and the edge of a high frequency hearing loss. Some individuals did exhibit a pitch at the low frequency edge of a hearing loss, but we could find no similar characteristics among these subjects. It is possible that a relationship between pitch and audiogram is present only in certain subgroups.

  11. Neuronal mechanisms underlying the perception of pitch and harmony.

    PubMed

    Langner, Gerald

    2005-12-01

    Temporal processing of periodic acoustic signals in the auditory brain stem provides an explanation for pitch perception and the natural preference of our hearing system for harmonic relationships in music. Experimental evidence is reviewed for a corresponding neuronal model of correlation analysis and the spatial representation of pitch information along the second neural axis of the auditory system.

  12. Microstructure and properties of pitch-based carbon composites

    PubMed

    Blanco; Santamaria; Bermejo; Bonhomme; Menendez

    1999-11-01

    Pitches prepared in the laboratory by thermal treatment and air-blowing of a commercial coal-tar pitch were used as matrix precursors of carbon composites using granular petroleum coke, foundry coke, amorphous graphite and anthracite. Pitches were characterized by standard procedures (elemental analysis, softening point, solubility tests and carbon yield) and light microscopy (mesophase content). Pitch pyrolysis behaviour was monitored by thermogravimetric analysis and from the optical texture of cokes. Pitch wettability to the different carbons, at different temperatures, was also studied. Experimental conditions selected for the preparation of composites were based on pitch composition and properties. The main microstructural features of composites were determined by light microscopy and scanning electron microscopy. Composite properties were described in terms of their density, porosity and compressive strength, and related to composite microstructure and the characteristics of the precursors. Thermal treatment and air-blowing of pitch improved carbon composite structure and properties. The lowest porosities and best mechanical properties were observed in those composites obtained with the thermally treated pitches combined with foundry coke and anthracite.

  13. Formation and behavior of carbonaceous mesophase in petroleum pitch

    SciTech Connect

    Stevens, W.C.

    1985-01-01

    The phase behavior of conventional liquid crystals with nonmesomorphs was studied and compared to mixtures of mesophase pitches with aromatic molecules. Experimental phase diagrams of p-polyphenyls, p-azoxyanisol and various aromatic molecules were used to estimate the virtual mesophase-isotropic transition temperatures of the latter. The mesophase-isotropic transition in mesophase pitch, hidden by reactions, decreases the solubility of nonmesomorphs as would be predicted by the phase behavior of conventional liquid crystals. From vapor osmometry, gel permeation chromatography and elemental analysis, models of Ashland 240 and a solvent extracted Ashland 240 mesophase pitch were developed. The 3 to 5-ringed aromatic species contained within Ashland 240 are the polymerized subunits forming the branched molecules of the solvent extracted mesophase pitch. The effects of air blowing, sparging and heat soaking on the nature and constitution of mesophase formed from Ashland 240 pitch also were examined and compared to the solvent extracted pitch. The nature and consequently the behavior of the mesophase formed was found to be process dependent. The utility of mesophase pitches is derived largely from the local molecular orientation. Experimentally observed changes in local order as a function of temperature and time at temperature were attributed to the hidden mesophase-isotropic transition temperature and the reactions which mask this transition. The orientation, relaxation, and stabilization of locally ordered subunits into an overall preferred orientation was examined by melt spinning mesophase pitches into fibers.

  14. The structure of mesophase fiber-forming pitches

    SciTech Connect

    Kirda, V.S.; Khrenkova, T.M.; Zamanova, L.V.; Nikolaeva, L.V.; Fedoseev, S.D.

    1993-12-31

    The structural features of several pitches, obtained from cracking residues and a pitch-like material, have been investigated as to their fiber-forming ability. The residues were obtained by heat treatments of cracking residues of a residual and two types of distillates. Infrared spectroscopy and x-ray diffraction results are discussed.

  15. Global and Local Pitch Perception in Children with Developmental Dyslexia

    ERIC Educational Resources Information Center

    Ziegler, Johannes C.; Pech-Georgel, Catherine; George, Florence; Foxton, Jessica M.

    2012-01-01

    This study investigated global versus local pitch pattern perception in children with dyslexia aged between 8 and 11 years. Children listened to two consecutive 4-tone pitch sequences while performing a same/different task. On the different trials, sequences either preserved the contour (local condition) or they violated the contour (global…

  16. 33 CFR 401.17 - Pitch indicators and alarms.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Pitch indicators and alarms. 401... indicators and alarms. Every vessel of 1600 gross registered tons or integrated tug and barge or articulated... propeller shall be equipped with— (a) A pitch indicator in the wheelhouse and the engine room; and...

  17. 14 CFR 25.1149 - Propeller speed and pitch controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Propeller speed and pitch controls. 25.1149... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Powerplant Controls and Accessories § 25.1149 Propeller speed and pitch controls. (a) There must be a separate propeller speed...

  18. 14 CFR 23.1149 - Propeller speed and pitch controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Propeller speed and pitch controls. 23.1149... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Powerplant Controls and Accessories § 23.1149 Propeller speed and pitch controls. (a) If there are...

  19. Estimates of pitch strength for musicians and nonmusicians

    NASA Astrophysics Data System (ADS)

    Clarkson, Marsha G.; Zettler, Cynthia M.; Follmer, Michelle J.; Faulk, Margaret; Takagi, Michael J.

    2003-04-01

    To measure the strength of the pitch of iterated rippled noise (IRN), 19 adults were tested in an operant conditioning procedure. Seven adults had music training and currently played an instrument; 12 adults had no training and did not currently play an instrument. To generate IRN, a 500-ms Gaussian noise stimulus was delayed by 5 or 6 ms (pitches of 200 or 166 Hz) and added to the original for 16 iterations. IRN stimuli having one delay were presented repeatedly. On signal trials the delay changed for 6 s. Stimulus level roved from 63-67 dBA (background of 28 dBA). Adults learned to press a button when the stimulus changed. Testing started with IRN stimuli having 0-dB attenuation (i.e., maximal pitch strength). Stimuli having weaker pitches (i.e., progressively greater attenuation applied to the delayed noise) followed. Strength of pitch was quantified as the maximum attenuation for which pitch was discerned. For each subject, threshold attenuation for pitch strength was extrapolated as the 71% point on a psychometric function depicting percent correct performance as a function of attenuation. Mean thresholds revealed that the pitch percept was similar for both nonmusically trained (18.70 dB) and musically trained adults (18.73 dB).

  20. 33 CFR 401.17 - Pitch indicators and alarms.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Pitch indicators and alarms. 401... indicators and alarms. Every vessel of 1600 gross registered tons or integrated tug and barge or articulated... propeller shall be equipped with— (a) A pitch indicator in the wheelhouse and the engine room; and...

  1. Cortical Basis for Dichotic Pitch Perception in Developmental Dyslexia

    ERIC Educational Resources Information Center

    Partanen, Marita; Fitzpatrick, Kevin; Madler, Burkhard; Edgell, Dorothy; Bjornson, Bruce; Giaschi, Deborah E.

    2012-01-01

    The current study examined auditory processing deficits in dyslexia using a dichotic pitch stimulus and functional MRI. Cortical activation by the dichotic pitch task occurred in bilateral Heschl's gyri, right planum temporale, and right superior temporal sulcus. Adolescents with dyslexia, relative to age-matched controls, illustrated greater…

  2. Pitch Perception, Working Memory, and Second-Language Phonological Production

    ERIC Educational Resources Information Center

    Posedel, James; Emery, Lisa; Souza, Benjamin; Fountain, Catherine

    2012-01-01

    Previous research has suggested that training on a musical instrument is associated with improvements in working memory and musical pitch perception ability. Good working memory and musical pitch perception ability, in turn, have been linked to certain aspects of language production. The current study examines whether working memory and/or pitch…

  3. The steady and transient rheological behavior or mesophase pitches

    SciTech Connect

    Fleurot, O.; Edie, D.D.

    1996-12-31

    Carbonaceous mesophase, a discotic, nematic liquid crystal, is a common precursor for the production of high performance (high thermal conductivity) carbon fibers. During melt spinning of mesophase pitches into fiber form, the poly-domain structure is stretched and oriented. A highly-oriented as-spun structure can be readily graphitized, giving the final heat-treated fiber superior thermal properties. Obviously, understanding, predicting, and ultimately controlling the development of structure is critical, if the final properties of mesophase pitch carbon fibers are to be optimized. While the development of structure in mesophase has been qualitatively described, quantitative information is needed. Complicating factors are: (i) the physical properties of mesophase pitches depend on the nature of the precursor material used to produce the liquid crystalline fluid, (ii) the rheological properties of mesophase are highly temperature-dependent, and (iii) mesophase pitch is optically opaque. In this work, the development of structure during steady and transient flow was investigated for different mesophase pitches.

  4. Mammalian pitch sensation shaped by the cochlear fluid

    NASA Astrophysics Data System (ADS)

    Gomez, Florian; Stoop, Ruedi

    2014-07-01

    The perceived pitch of a complex harmonic sound changes if the partial tones of the sound are frequency shifted by a fixed amount. Simple mathematical rules are expected to govern perceived pitch, but these rules are violated in psychoacoustic experiments. Cognitive cortical processes are commonly held responsible for this discrepancy. Here, we demonstrate that this need not be the case. We show that human pitch perception can be reproduced with a biophysically motivated mesoscopic model of the cochlea, by fully recovering published psychoacoustical pitch-shift data and related physiological measurements from the cat cochlear nucleus. Our study suggests that perceived pitch can be attributed to combination tones in the presence of a cochlear fluid.

  5. First North American longwall in pitching seams proven feasible. [Colorado

    SciTech Connect

    Reynolds, J.F.

    1983-12-01

    There are 1.4 Gt (1.5 billion st) of recoverable coal under less than 914 m (3,000 ft) of cover in Colorado in pitching seams. Snowmass Coal Co., in cooperation with the US Department of Energy, introduced the longwall mining method in pitching seams to North America. This venture is a coal mining research program directed toward the profitable production of coal under difficult mining conditions as found in pitching seams of the western US. Snowmass Coal classifies pitching seams into the following categories for longwall on the strike in seams 3 m (10 ft) or less thick: Flat = 0 to 10/sup 0/: Normal continuous mines and shuttle cars work efficiently. Slight = 10/sup 0/ to 22/sup 0/: The maximum pitch that rubber tired equipment will function. Moderate = 22/sup 0/ to 40/sup 0/: The angle of repose of mined coal. Steep = 40/sup 0/ to 60/sup 0/: The limit of safe use of this roof support. Vertical = over 60/sup 0/. The longwall roof support covered here will work in all pitches except vertical. The shearer and conveyor will work in flat through moderate conditions. Longwalling across strike with this equipment in seam pitch over 60/sup 0/ could be accomplished with an inclined face. Development of the first longwall panel began in 1979 and was completed in 1981. The longwall equipment was installed and mining began on Aug. 11, 1981. Snowmass' performance shows that the capacity of a longwall operating on moderate pitch, up to 45/sup 0/, should be the same as a flat seam longwall. With equipment now available, pitching seam longwall is not only feasible, but cost competitive. The actual roof support method of troika concept has excellent maneuverability, good support, and low maintenance. The shearer has proven power to operate on moderate pitching seams.

  6. High performance uncooled amorphous silicon VGA IRFPA with 17-µm pixel-pitch

    NASA Astrophysics Data System (ADS)

    Tissot, J. L.; Durand, A.; Garret, Th.; Minassian, C.; Robert, P.; Tinnes, S.; Vilain, M.

    2010-04-01

    The high level of accumulated expertise by ULIS and CEA/LETI on uncooled microbolometers made from amorphous silicon enables ULIS to develop VGA IRFPA formats with 17μm pixel-pitch to build up the currently available product catalog. This detector keeps all the innovations developed on the 25 μm pixel-pitch ROIC (detector configuration by serial link, low power consumption and wide electrical dynamic range). The specific appeal of this unit lies in the high spatial resolution it provides. The reduction of the pixel-pitch turns this TEC-less VGA array into a product well adapted for high resolution and compact systems. In the last part of the paper, we will look more closely at the high electro-optical performances of this IRFPA and the rapid performance enhancement. We will insist on NETD trade-off with wide thermal dynamic range, as well as the high characteristics uniformity, achieved thanks to the mastering of the amorphous silicon technology coupled with the ROIC design. This technology node paves the way to high end products as well as low end compact smaller formats like 160 x 120 or smaller.

  7. Modeling source-filter interaction in belting and high-pitched operatic male singing.

    PubMed

    Titze, Ingo R; Worley, Albert S

    2009-09-01

    Nonlinear source-filter theory is applied to explain some acoustic differences between two contrasting male singing productions at high pitches: operatic style versus jazz belt or theater belt. Several stylized vocal tract shapes (caricatures) are discussed that form the bases of these styles. It is hypothesized that operatic singing uses vowels that are modified toward an inverted megaphone mouth shape for transitioning into the high-pitch range. This allows all the harmonics except the fundamental to be "lifted" over the first formant. Belting, on the other hand, uses vowels that are consistently modified toward the megaphone (trumpet-like) mouth shape. Both the fundamental and the second harmonic are then kept below the first formant. The vocal tract shapes provide collective reinforcement to multiple harmonics in the form of inertive supraglottal reactance and compliant subglottal reactance. Examples of lip openings from four well-known artists are used to infer vocal tract area functions and the corresponding reactances.

  8. A vision framework for the localization of soccer players and ball on the pitch using Handycams

    NASA Astrophysics Data System (ADS)

    Vilas, Tiago; Rodrigues, J. M. F.; Cardoso, P. J. S.; Silva, Bruno

    2015-03-01

    The current performance requirements in soccer make imperative the use of new technologies for game observation and analysis, such that detailed information about the teams' actions is provided. This paper summarizes a framework to collect the soccer players and ball positions using one or more Full HD Handycams, placed no more than 20cm apart in the stands, as well as how this framework connects to the FootData project. The system was based on four main modules: the detection and delimitation of the soccer pitch, the ball and the players detection and assignment to their teams, the tracking of players and ball and finally the computation of their localization (in meters) in the pitch.

  9. Representations of Pitch and Timbre Variation in Human Auditory Cortex.

    PubMed

    Allen, Emily J; Burton, Philip C; Olman, Cheryl A; Oxenham, Andrew J

    2017-02-01

    Pitch and timbre are two primary dimensions of auditory perception, but how they are represented in the human brain remains a matter of contention. Some animal studies of auditory cortical processing have suggested modular processing, with different brain regions preferentially coding for pitch or timbre, whereas other studies have suggested a distributed code for different attributes across the same population of neurons. This study tested whether variations in pitch and timbre elicit activity in distinct regions of the human temporal lobes. Listeners were presented with sequences of sounds that varied in either fundamental frequency (eliciting changes in pitch) or spectral centroid (eliciting changes in brightness, an important attribute of timbre), with the degree of pitch or timbre variation in each sequence parametrically manipulated. The BOLD responses from auditory cortex increased with increasing sequence variance along each perceptual dimension. The spatial extent, region, and laterality of the cortical regions most responsive to variations in pitch or timbre at the univariate level of analysis were largely overlapping. However, patterns of activation in response to pitch or timbre variations were discriminable in most subjects at an individual level using multivoxel pattern analysis, suggesting a distributed coding of the two dimensions bilaterally in human auditory cortex.

  10. Experiments to investigate lift production mechanisms on pitching flat plates

    NASA Astrophysics Data System (ADS)

    Stevens, P. R. R. J.; Babinsky, H.

    2017-01-01

    Pitching flat plates are a useful simplification of flapping wings, and their study can provide useful insights into unsteady force generation. Non-circulatory and circulatory lift producing mechanisms for low Reynolds number pitching flat plates are investigated. A series of experiments are designed to measure forces and study the unsteady flowfield development. Two pitch axis positions are investigated, namely a leading edge and a mid-chord pitch axis. A novel PIV approach using twin laser lightsheets is shown to be effective at acquiring full field of view velocity data when an opaque wing model is used. Leading-edge vortex (LEV) circulations are extracted from velocity field data, using a Lamb-Oseen vortex fitting algorithm. LEV and trailing-edge vortex positions are also extracted. It is shown that the circulation of the LEV, as determined from PIV data, approximately matches the general trend of an unmodified Wagner function for a leading edge pitch axis and a modified Wagner function for a mid-chord pitch axis. Comparison of experimentally measured lift correlates well with the prediction of a reduced-order model for a LE pitch axis.

  11. Long-pitch cholesteric liquid crystals for display applications

    NASA Astrophysics Data System (ADS)

    Yoon, Tae-Hoon; Huh, Jae-Won; Yu, Byeong-Hun

    2014-02-01

    Cholesteric liquid crystals (CLCs) have been used for a reflective display because of their reflective nature in the planar state. In a reflective display, the planar and the focal-conic states are used for the bright state and the dark state, respectively. In this paper we introduce a long-pitch CLC device, in which a selective wavelength of the reflected light is shifted to infrared (IR) wavelengths by controlling the pitch. The planar state of a long-pitch CLC device is transparent over the entire visible wavelengths in the field-off state. Omni-directional achromatic reflection through light scattering in the focal-conic state can be achieved without a polarizer. Compared to conventional CLC cells that reflect the visible light in the planar state, a long-pitch CLC device has a longer pitch, of which the operating voltage for switching between the two state is much lower so that achromatic reflective displays and light shutters with low power consumption can be realized using long-pitch CLC devices. By coupling with a reflector, the light efficiency of a longpitch CLC cell in the focal-conic state can be enhanced, by which higher brightness can be obtained for application to reflective displays. A dye-doped long-pitch CLC device can be placed behind a transparent organic light-emitting diode display for use as a light shutter to block the ambient light.

  12. Auditory working memory predicts individual differences in absolute pitch learning.

    PubMed

    Van Hedger, Stephen C; Heald, Shannon L M; Koch, Rachelle; Nusbaum, Howard C

    2015-07-01

    Absolute pitch (AP) is typically defined as the ability to label an isolated tone as a musical note in the absence of a reference tone. At first glance the acquisition of AP note categories seems like a perceptual learning task, since individuals must assign a category label to a stimulus based on a single perceptual dimension (pitch) while ignoring other perceptual dimensions (e.g., loudness, octave, instrument). AP, however, is rarely discussed in terms of domain-general perceptual learning mechanisms. This is because AP is typically assumed to depend on a critical period of development, in which early exposure to pitches and musical labels is thought to be necessary for the development of AP precluding the possibility of adult acquisition of AP. Despite this view of AP, several previous studies have found evidence that absolute pitch category learning is, to an extent, trainable in a post-critical period adult population, even if the performance typically achieved by this population is below the performance of a "true" AP possessor. The current studies attempt to understand the individual differences in learning to categorize notes using absolute pitch cues by testing a specific prediction regarding cognitive capacity related to categorization - to what extent does an individual's general auditory working memory capacity (WMC) predict the success of absolute pitch category acquisition. Since WMC has been shown to predict performance on a wide variety of other perceptual and category learning tasks, we predict that individuals with higher WMC should be better at learning absolute pitch note categories than individuals with lower WMC. Across two studies, we demonstrate that auditory WMC predicts the efficacy of learning absolute pitch note categories. These results suggest that a higher general auditory WMC might underlie the formation of absolute pitch categories for post-critical period adults. Implications for understanding the mechanisms that underlie the

  13. A New Approach to Model Pitch Perception Using Sparse Coding

    PubMed Central

    Furst, Miriam; Barak, Omri

    2017-01-01

    Our acoustical environment abounds with repetitive sounds, some of which are related to pitch perception. It is still unknown how the auditory system, in processing these sounds, relates a physical stimulus and its percept. Since, in mammals, all auditory stimuli are conveyed into the nervous system through the auditory nerve (AN) fibers, a model should explain the perception of pitch as a function of this particular input. However, pitch perception is invariant to certain features of the physical stimulus. For example, a missing fundamental stimulus with resolved or unresolved harmonics, or a low and high-level amplitude stimulus with the same spectral content–these all give rise to the same percept of pitch. In contrast, the AN representations for these different stimuli are not invariant to these effects. In fact, due to saturation and non-linearity of both cochlear and inner hair cells responses, these differences are enhanced by the AN fibers. Thus there is a difficulty in explaining how pitch percept arises from the activity of the AN fibers. We introduce a novel approach for extracting pitch cues from the AN population activity for a given arbitrary stimulus. The method is based on a technique known as sparse coding (SC). It is the representation of pitch cues by a few spatiotemporal atoms (templates) from among a large set of possible ones (a dictionary). The amount of activity of each atom is represented by a non-zero coefficient, analogous to an active neuron. Such a technique has been successfully applied to other modalities, particularly vision. The model is composed of a cochlear model, an SC processing unit, and a harmonic sieve. We show that the model copes with different pitch phenomena: extracting resolved and non-resolved harmonics, missing fundamental pitches, stimuli with both high and low amplitudes, iterated rippled noises, and recorded musical instruments. PMID:28099436

  14. Electrode coke production from pitch by retarded carbonization

    SciTech Connect

    Pityulin, I.N.; Krysin, V.P.; Stepanenko, M.A.; Akhtyrchenko, A.M.; Balabai, V.M.; Slutskaya, S.M.

    1981-01-01

    Pitch coke is a key constituent of the anode used in aluminum smelting. Hitherto, pitch coke has been produced by an oven carbonization process in which hard pitch is heated to 950 to 970/sup 0/C in silica-brick coke ovens. The main advantage of the process is that it can produce a carbon material with a low volatile matter index. On the other hand, the oven carbonization process involves a number of problems which cannot easily be overcome, relating to limited labor productivity and oven life and atmospheric pollution with toxic discharges. Retarded carbonization is a superior method of making electrode coke from pitch, since the costs are lower, the working conditions are less arduous and atmospheric pollution is greatly reduced. Following laboratory and pilot plant investigations, a flowsheet has been developed and optimum conditions have been worked out for the production of finished electrode coke. The raw material is coal tar; it is dewatered in the stage I evaporator and then distilled to make a soft pitch as the carbonization feedstock. Thus the dewatered tar is heated in the stage II tube still and separated in the stage II evaporator into distillate and pitch. The pitch from the column base is heated to a higher temperature and transferred to the column in which it is prepared for carbonization (by mass exchange with carbonization gases and vapors). The bottom section of the column yields the secondary carbonization feedstock, which is heated in a stage II tube still and transferred to one of the carbonization vessels. The temperature setting is determined by the quality of the original soft pitch. Table 1 records the properties of the coal tar, the soft pitch and the secondary carbonization feedstock.

  15. Loudness and pitch of Kunqu opera.

    PubMed

    Dong, Li; Sundberg, Johan; Kong, Jiangping

    2014-01-01

    Equivalent sound level (Leq), sound pressure level (SPL), and fundamental frequency (F0) are analyzed in each of five Kunqu Opera roles, Young girl and Young woman, Young man, Old man, and Colorful face. Their pitch ranges are similar to those of some western opera singers (alto, alto, tenor, baritone, and baritone, respectively). Differences among tasks, conditions (stage speech, singing, and reading lyrics), singers, and roles are examined. For all singers, Leq of stage speech and singing were considerably higher than that of conversational speech. Interrole differences of Leq among tasks and singers were larger than the intrarole differences. For most roles, time domain variation of SPL differed between roles both in singing and stage speech. In singing, as compared with stage speech, SPL distribution was more concentrated and variation of SPL with time was smaller. With regard to gender and age, male roles had higher mean Leq and lower average F0, MF0, as compared with female roles. Female singers showed a wider F0 distribution for singing than for stage speech, whereas the opposite was true for male singers. The Leq of stage speech was higher than in singing for young personages. Younger female personages showed higher Leq, whereas older male personages had higher Leq. The roles performed with higher Leq tended to be sung at a lower MF0.

  16. Biomechanics of baseball pitching. A preliminary report.

    PubMed

    Pappas, A M; Zawacki, R M; Sullivan, T J

    1985-01-01

    Fifteen professional major league pitchers were filmed with high speed cinematography. One hundred forty-seven pitches were analyzed using an electromagnetic digitizer and a microcomputer. Three phases of throwing were studied: cocking, acceleration, and follow-through. The cocking phase is the period of time between the initiation of the windup and the moment at which the shoulder is in maximum external rotation. This phase occurs in approximately 1500 ms, and the shoulder is brought into an extreme position of external rotation. The acceleration phase and the initial stages of the follow-through phase produce extraordinary demands on the shoulder and elbow. The acceleration phase begins with the throwing shoulder in the position of maximum external rotation and terminates with ball release. This phase occurs in approximately 50 ms, and peak angular velocities averaging 6,180 deg/sec for shoulder internal rotation and 4,595 deg/sec for elbow extension were measured. The follow-through phase begins at ball release and continues until the motion of throwing has ceased. This phase occurs in approximately 350 ms.

  17. Learning Pitch with STDP: A Computational Model of Place and Temporal Pitch Perception Using Spiking Neural Networks

    PubMed Central

    Erfanian Saeedi, Nafise; Blamey, Peter J.; Burkitt, Anthony N.; Grayden, David B.

    2016-01-01

    Pitch perception is important for understanding speech prosody, music perception, recognizing tones in tonal languages, and perceiving speech in noisy environments. The two principal pitch perception theories consider the place of maximum neural excitation along the auditory nerve and the temporal pattern of the auditory neurons’ action potentials (spikes) as pitch cues. This paper describes a biophysical mechanism by which fine-structure temporal information can be extracted from the spikes generated at the auditory periphery. Deriving meaningful pitch-related information from spike times requires neural structures specialized in capturing synchronous or correlated activity from amongst neural events. The emergence of such pitch-processing neural mechanisms is described through a computational model of auditory processing. Simulation results show that a correlation-based, unsupervised, spike-based form of Hebbian learning can explain the development of neural structures required for recognizing the pitch of simple and complex tones, with or without the fundamental frequency. The temporal code is robust to variations in the spectral shape of the signal and thus can explain the phenomenon of pitch constancy. PMID:27049657

  18. Spatial representation of pitch height: the SMARC effect.

    PubMed

    Rusconi, Elena; Kwan, Bonnie; Giordano, Bruno L; Umiltà, Carlo; Butterworth, Brian

    2006-03-01

    Through the preferential pairing of response positions to pitch, here we show that the internal representation of pitch height is spatial in nature and affects performance, especially in musically trained participants, when response alternatives are either vertically or horizontally aligned. The finding that our cognitive system maps pitch height onto an internal representation of space, which in turn affects motor performance even when this perceptual attribute is irrelevant to the task, extends previous studies on auditory perception and suggests an interesting analogy between music perception and mathematical cognition. Both the basic elements of mathematical cognition (i.e. numbers) and the basic elements of musical cognition (i.e. pitches), appear to be mapped onto a mental spatial representation in a way that affects motor performance.

  19. A Computationally Efficient Method for Polyphonic Pitch Estimation

    NASA Astrophysics Data System (ADS)

    Zhou, Ruohua; Reiss, Joshua D.; Mattavelli, Marco; Zoia, Giorgio

    2009-12-01

    This paper presents a computationally efficient method for polyphonic pitch estimation. The method employs the Fast Resonator Time-Frequency Image (RTFI) as the basic time-frequency analysis tool. The approach is composed of two main stages. First, a preliminary pitch estimation is obtained by means of a simple peak-picking procedure in the pitch energy spectrum. Such spectrum is calculated from the original RTFI energy spectrum according to harmonic grouping principles. Then the incorrect estimations are removed according to spectral irregularity and knowledge of the harmonic structures of the music notes played on commonly used music instruments. The new approach is compared with a variety of other frame-based polyphonic pitch estimation methods, and results demonstrate the high performance and computational efficiency of the approach.

  20. Investors prefer entrepreneurial ventures pitched by attractive men

    PubMed Central

    Brooks, Alison Wood; Huang, Laura; Kearney, Sarah Wood; Murray, Fiona E.

    2014-01-01

    Entrepreneurship is a central path to job creation, economic growth, and prosperity. In the earliest stages of start-up business creation, the matching of entrepreneurial ventures to investors is critically important. The entrepreneur’s business proposition and previous experience are regarded as the main criteria for investment decisions. Our research, however, documents other critical criteria that investors use to make these decisions: the gender and physical attractiveness of the entrepreneurs themselves. Across a field setting (three entrepreneurial pitch competitions in the United States) and two experiments, we identify a profound and consistent gender gap in entrepreneur persuasiveness. Investors prefer pitches presented by male entrepreneurs compared with pitches made by female entrepreneurs, even when the content of the pitch is the same. This effect is moderated by male physical attractiveness: attractive males were particularly persuasive, whereas physical attractiveness did not matter among female entrepreneurs. PMID:24616491

  1. Analysis of rotor vibratory loads using higher harmonic pitch control

    NASA Technical Reports Server (NTRS)

    Quackenbush, Todd R.; Bliss, Donald B.; Boschitsch, Alexander H.; Wachspress, Daniel A.

    1992-01-01

    Experimental studies of isolated rotors in forward flight have indicated that higher harmonic pitch control can reduce rotor noise. These tests also show that such pitch inputs can generate substantial vibratory loads. The modification is summarized of the RotorCRAFT (Computation of Rotor Aerodynamics in Forward flighT) analysis of isolated rotors to study the vibratory loading generated by high frequency pitch inputs. The original RotorCRAFT code was developed for use in the computation of such loading, and uses a highly refined rotor wake model to facilitate this task. The extended version of RotorCRAFT incorporates a variety of new features including: arbitrary periodic root pitch control; computation of blade stresses and hub loads; improved modeling of near wake unsteady effects; and preliminary implementation of a coupled prediction of rotor airloads and noise. Correlation studies are carried out with existing blade stress and vibratory hub load data to assess the performance of the extended code.

  2. Human vertical eye movement responses to earth horizontal pitch

    NASA Technical Reports Server (NTRS)

    Wall, C. 3rd; Petropoulos, A. E.

    1993-01-01

    The vertical eye movements in humans produced in response to head-over-heels constant velocity pitch rotation about a horizontal axis resemble those from other species. At 60 degrees/s these are persistent and tend to have non-reversing slow components that are compensatory to the direction of rotation. In most, but not all subjects, the slow component velocity was well characterized by a rapid build-up followed by an exponential decay to a non-zero baseline. Super-imposed was a cyclic or modulation component whose frequency corresponded to the time for one revolution and whose maximum amplitude occurred during a specific head orientation. All response components (exponential decay, baseline and modulation) were larger during pitch backward compared to pitch forward runs. Decay time constants were shorter during the backward runs, thus, unlike left to right yaw axis rotation, pitch responses display significant asymmetries between paired forward and backward runs.

  3. Investors prefer entrepreneurial ventures pitched by attractive men.

    PubMed

    Brooks, Alison Wood; Huang, Laura; Kearney, Sarah Wood; Murray, Fiona E

    2014-03-25

    Entrepreneurship is a central path to job creation, economic growth, and prosperity. In the earliest stages of start-up business creation, the matching of entrepreneurial ventures to investors is critically important. The entrepreneur's business proposition and previous experience are regarded as the main criteria for investment decisions. Our research, however, documents other critical criteria that investors use to make these decisions: the gender and physical attractiveness of the entrepreneurs themselves. Across a field setting (three entrepreneurial pitch competitions in the United States) and two experiments, we identify a profound and consistent gender gap in entrepreneur persuasiveness. Investors prefer pitches presented by male entrepreneurs compared with pitches made by female entrepreneurs, even when the content of the pitch is the same. This effect is moderated by male physical attractiveness: attractive males were particularly persuasive, whereas physical attractiveness did not matter among female entrepreneurs.

  4. Nonlinear Dynamics of the Perceived Pitch of Complex Sounds

    NASA Astrophysics Data System (ADS)

    Cartwright, Julyan H. E.; González, Diego L.; Piro, Oreste

    1999-06-01

    We apply results from nonlinear dynamics to an old problem in acoustical physics: the mechanism of the perception of the pitch of sounds, especially the sounds known as complex tones that are important for music and speech intelligibility.

  5. 14 CFR 23.33 - Propeller speed and pitch limits.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... For each propeller whose pitch cannot be controlled in flight— (1) During takeoff and initial climb at the all engine(s) operating climb speed specified in § 23.65, the propeller must limit the engine...

  6. 14 CFR 23.33 - Propeller speed and pitch limits.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .... For each propeller whose pitch cannot be controlled in flight— (1) During takeoff and initial climb at the all engine(s) operating climb speed specified in § 23.65, the propeller must limit the engine...

  7. Articulatory configuration and pitch in a classically trained soprano singer.

    PubMed

    Sundberg, Johan

    2009-09-01

    Previous studies suggest that singers modify articulation to avoid that the pitch frequency F0 exceeds the normal value of the first formant F1(Normal). Using magnetic resonance imaging at a rate of 5 frames/s, articulation was analyzed in a professional soprano singing an ascending triad pattern from C4 to G5 (262-784Hz) on the vowels /i, e, u, o, a/. Lip and jaw opening and tongue dorsum height were measured and analyzed as function of pitch. Four or five semitones below the pitch where F0=F1(Normal) the tongue dorsum height was reduced in /i, e, u, a/, whereas in /o/ the lip opening was widened and in /a/ also the jaw opening was widened. At higher pitches, the jaw opening was widened in all vowels. These articulatory maneuvers are likely to raise F1 in these vowels.

  8. Fixed pitch rotor performance of large horizontal axis wind turbines

    NASA Technical Reports Server (NTRS)

    Viterna, L. A.; Corrigan, R. D.

    1982-01-01

    Experimental fixed pitch wind turbine performance data is presented for both the DOE/NASA Mod-0 and the Danish Gedser wind turbines. Furthermore, a method for calculating the output power from large fixed pitch wind turbines is presented. Modifications to classical blade element momentum theory are given that improve correlation with measured data. Improvement is particularly evident in high winds (low tip speed ratios) where aerodynamic stall occurs as the blade experiences high angles of attack.

  9. Cosmic-ray pitch-angle scattering in isotropic turbulence

    NASA Technical Reports Server (NTRS)

    Bieber, John W.; Smith, Charles W.; Matthaeus, William H.

    1988-01-01

    A dissipation range is incorporated in the turbulence model to reconcile the divergent conclusions from studies of cosmic-ray pitch-angle scattering in isotropic magnetic turbulence. The Fokker-Planck coefficient for pitch-angle scattering is calculated. It is shown that the slab form of the Fokker-Plank coefficient (Jokipii, 1966) is valid at very low energies, while the nonslab form (Fisk, 1974) is valid at intermediate energies.

  10. Production of graphene oxide from pitch-based carbon fiber.

    PubMed

    Lee, Miyeon; Lee, Jihoon; Park, Sung Young; Min, Byunggak; Kim, Bongsoo; In, Insik

    2015-07-09

    Pitch-based graphene oxide (p-GO) whose compositional/structural features are comparable to those of graphene oxide (GO) was firstly produced by chemical exfoliation of pitch-based carbon fiber rather than natural graphite. Incorporation of p-GO as nanofillers into poly(methyl methacrylate) (PMMA) as a matrix polymer resulted in excellent mechanical reinforcement. p-GO/PMMA nanocomposite (1 wt.-% p-GO) demonstrated 800% higher modulus of toughness of neat PMMA.

  11. Production of graphene oxide from pitch-based carbon fiber

    NASA Astrophysics Data System (ADS)

    Lee, Miyeon; Lee, Jihoon; Park, Sung Young; Min, Byunggak; Kim, Bongsoo; in, Insik

    2015-07-01

    Pitch-based graphene oxide (p-GO) whose compositional/structural features are comparable to those of graphene oxide (GO) was firstly produced by chemical exfoliation of pitch-based carbon fiber rather than natural graphite. Incorporation of p-GO as nanofillers into poly(methyl methacrylate) (PMMA) as a matrix polymer resulted in excellent mechanical reinforcement. p-GO/PMMA nanocomposite (1 wt.-% p-GO) demonstrated 800% higher modulus of toughness of neat PMMA.

  12. Enhanced brainstem encoding predicts musicians' perceptual advantages with pitch.

    PubMed

    Bidelman, Gavin M; Krishnan, Ananthanarayan; Gandour, Jackson T

    2011-02-01

    Important to Western tonal music is the relationship between pitches both within and between musical chords; melody and harmony are generated by combining pitches selected from the fixed hierarchical scales of music. It is of critical importance that musicians have the ability to detect and discriminate minute deviations in pitch in order to remain in tune with other members of their ensemble. Event-related potentials indicate that cortical mechanisms responsible for detecting mistuning and violations in pitch are more sensitive and accurate in musicians as compared with non-musicians. The aim of the present study was to address whether this superiority is also present at a subcortical stage of pitch processing. Brainstem frequency-following responses were recorded from musicians and non-musicians in response to tuned (i.e. major and minor) and detuned (± 4% difference in frequency) chordal arpeggios differing only in the pitch of their third. Results showed that musicians had faster neural synchronization and stronger brainstem encoding for defining characteristics of musical sequences regardless of whether they were in or out of tune. In contrast, non-musicians had relatively strong representation for major/minor chords but showed diminished responses for detuned chords. The close correspondence between the magnitude of brainstem responses and performance on two behavioral pitch discrimination tasks supports the idea that musicians' enhanced detection of chordal mistuning may be rooted at pre-attentive, sensory stages of processing. Findings suggest that perceptually salient aspects of musical pitch are not only represented at subcortical levels but that these representations are also enhanced by musical experience.

  13. Production of graphene oxide from pitch-based carbon fiber

    PubMed Central

    Lee, Miyeon; Lee, Jihoon; Park, Sung Young; Min, Byunggak; Kim, Bongsoo; In, Insik

    2015-01-01

    Pitch-based graphene oxide (p-GO) whose compositional/structural features are comparable to those of graphene oxide (GO) was firstly produced by chemical exfoliation of pitch-based carbon fiber rather than natural graphite. Incorporation of p-GO as nanofillers into poly(methyl methacrylate) (PMMA) as a matrix polymer resulted in excellent mechanical reinforcement. p-GO/PMMA nanocomposite (1 wt.-% p-GO) demonstrated 800% higher modulus of toughness of neat PMMA. PMID:26156067

  14. Collisionless pitch-angle scattering of runaway electrons

    NASA Astrophysics Data System (ADS)

    Liu, Jian; Wang, Yulei; Qin, Hong

    2016-06-01

    It is discovered that the tokamak field geometry generates a toroidicity induced broadening of the pitch-angle distribution of runaway electrons. This collisionless pitch-angle scattering is much stronger than the collisional scattering and invalidates the gyro-center model for runaway electrons. As a result, the energy limit of runaway electrons is found to be larger than the prediction of the gyro-center model and to depend heavily on the background magnetic field.

  15. Processing of pitch and time sequences in music.

    PubMed

    Neuhaus, Christiane; Knösche, Thomas R

    2008-08-15

    Pitch and duration -- either as written symbols or in auditory form -- are the basic structural properties in tones that form a melodic sequence. From the cognitive perspective, it is still a matter of debate whether, and at which processing stage, these two factors are processed independently or interdependently. The present study addresses this issue from the neuroscientist's point of view by measuring event-related potentials (ERPs) in musicians and non-musicians. Either the pitches or the durations of the tones, or both, were permuted randomly over a set of melodies in order to remove all sequential ordering with respect to these factors. Effects of both, pitch and time order, on the peak amplitudes of the P1-N1-P2 complex were observed. ANOVA revealed that sequential processing may depend on the different levels of skill in analytical hearing. For musicians, strong interaction effects for all three ERP components corroborated the interdependence of pitch and time processing. Musicians also seem to rely on coherent time structure more than non-musicians and showed enlarged P1 and P2 components whenever tone duration, either with or without preserved pitch, was at random. Non-musicians tend to use ordered pitch relations for perceptual orientation, and main effects without any interactions might indicate some kind of independent processing of both dimensions at some processing stages.

  16. Temporal pitch perception at high rates in cochlear implants.

    PubMed

    Kong, Ying-Yee; Carlyon, Robert P

    2010-05-01

    A recent study reported that a group of Med-El COMBI 40+CI (cochlear implant) users could, in a forced-choice task, detect changes in the rate of a pulse train for rates higher than the 300 pps "upper limit" commonly reported in the literature [Kong, Y.-Y., et al. (2009). J. Acoust. Soc. Am. 125, 1649-1657]. The present study further investigated the upper limit of temporal pitch in the same group of CI users on three tasks [pitch ranking, rate discrimination, and multidimensional scaling (MDS)]. The patterns of results were consistent across the three tasks and all subjects could follow rate changes above 300 pps. Two subjects showed exceptional ability to follow temporal pitch change up to about 900 pps. Results from the MDS study indicated that, for the two listeners tested, changes in pulse rate over the range of 500-840 pps were perceived along a perceptual dimension that was orthogonal to the place of excitation. Some subjects showed a temporal pitch reversal at rates beyond their upper limit of pitch and some showed a reversal within a small range of rates below the upper limit. These results are discussed in relation to the possible neural bases for temporal pitch processing at high rates.

  17. Relative saliency of pitch versus phonetic cues in infancy

    NASA Astrophysics Data System (ADS)

    Cardillo, Gina; Kuhl, Patricia; Sundara, Megha

    2005-09-01

    Infants in their first year are highly sensitive to different acoustic components of speech, including phonetic detail and pitch information. The present investigation examined whether relative sensitivity to these two dimensions changes during this period, as the infant acquires language-specific phonetic categories. If pitch and phonetic discrimination are hierarchical, then the relative salience of pitch and phonetic change may become reversed between 8 and 12 months of age. Thirty-two- and 47-week-old infants were tested using an auditory preference paradigm in which they first heard a recording of a person singing a 4-note song (i.e., ``go-bi-la-tu'') and were then presented with both the familiar and an unfamiliar, modified version of that song. Modifications were either a novel pitch order (keeping syllables constant) or a novel syllable order (keeping melody constant). Compared to the younger group, older infants were predicted to show greater relative sensitivity to syllable order than pitch order, in accordance with an increased tendency to attend to linguistically relevant information (phonetic patterns) as opposed to cues that are initially more salient (pitch patterns). Preliminary data show trends toward the predicted interaction, with preference patterns commensurate with previously reported data. [Work supported by the McDonnell Foundation and NIH.

  18. Manufacture of threads with variable pitch by using noncircular gears

    NASA Astrophysics Data System (ADS)

    Slătineanu, L.; Dodun, O.; Coteață, M.; Coman, I.; Nagîț, G.; Beșliu, I.

    2016-08-01

    There are mechanical equipments in which shafts threaded with variable pitch are included. Such a shaft could be met in the case of worm specific to the double enveloping worm gearing. Over the years, the researchers investigated some possibilities to geometrically define and manufacture the shaft zones characterized by a variable pitch. One of the methods able to facilitate the manufacture of threads with variable pitch is based on the use of noncircular gears in the threading kinematic chain for threading by cutting. In order to design the noncircular gears, the mathematical law of pitch variation has to be known. An analysis of pitch variation based on geometrical considerations was developed in the case of a double enveloping globoid worm. Subsequently, on the bases of a proper situation, a numerical model was determined. In this way, an approximately law of pitch variation was determined and it could be taken into consideration when designing the noncircular gears included in the kinematic chain of the cutting machine tool.

  19. When pitch Accents Encode Speaker Commitment: Evidence from French Intonation.

    PubMed

    Michelas, Amandine; Portes, Cristel; Champagne-Lavau, Maud

    2016-06-01

    Recent studies on a variety of languages have shown that a speaker's commitment to the propositional content of his or her utterance can be encoded, among other strategies, by pitch accent types. Since prior research mainly relied on lexical-stress languages, our understanding of how speakers of a non-lexical-stress language encode speaker commitment is limited. This paper explores the contribution of the last pitch accent of an intonation phrase to convey speaker commitment in French, a language that has stress at the phrasal level as well as a restricted set of pitch accents. In a production experiment, participants had to produce sentences in two pragmatic contexts: unbiased questions (the speaker had no particular belief with respect to the expected answer) and negatively biased questions (the speaker believed the proposition to be false). Results revealed that negatively biased questions consistently exhibited an additional unaccented F0 peak in the preaccentual syllable (an H+!H* pitch accent) while unbiased questions were often realized with a rising pattern across the accented syllable (an H* pitch accent). These results provide evidence that pitch accent types in French can signal the speaker's belief about the certainty of the proposition expressed in French. It also has implications for the phonological model of French intonation.

  20. Adaptive management

    USGS Publications Warehouse

    Allen, Craig R.; Garmestani, Ahjond S.

    2015-01-01

    Adaptive management is an approach to natural resource management that emphasizes learning through management where knowledge is incomplete, and when, despite inherent uncertainty, managers and policymakers must act. Unlike a traditional trial and error approach, adaptive management has explicit structure, including a careful elucidation of goals, identification of alternative management objectives and hypotheses of causation, and procedures for the collection of data followed by evaluation and reiteration. The process is iterative, and serves to reduce uncertainty, build knowledge and improve management over time in a goal-oriented and structured process.

  1. Dynamics of high-bypass-engine thrust reversal using a variable-pitch fan

    NASA Technical Reports Server (NTRS)

    Schaefer, J. W.; Sagerser, D. R.; Stakolich, E. G.

    1977-01-01

    The test program demonstrated that successful and rapid forward-to reverse-thrust transients can be performed without any significant engine operational limitations for fan blade pitch changes through either feather pitch or flat pitch. For through-feather-pitch operation with a flight inlet, fan stall problems were encountered, and a fan blade overshoot technique was used to establish reverse thrust.

  2. Perceptual distortions in pitch and time reveal active prediction and support for an auditory pitch-motion hypothesis.

    PubMed

    Henry, Molly J; McAuley, J Devin

    2013-01-01

    A number of accounts of human auditory perception assume that listeners use prior stimulus context to generate predictions about future stimulation. Here, we tested an auditory pitch-motion hypothesis that was developed from this perspective. Listeners judged either the time change (i.e., duration) or pitch change of a comparison frequency glide relative to a standard (referent) glide. Under a constant-velocity assumption, listeners were hypothesized to use the pitch velocity (Δf/Δt) of the standard glide to generate predictions about the pitch velocity of the comparison glide, leading to perceptual distortions along the to-be-judged dimension when the velocities of the two glides differed. These predictions were borne out in the pattern of relative points of subjective equality by a significant three-way interaction between the velocities of the two glides and task. In general, listeners' judgments along the task-relevant dimension (pitch or time) were affected by expectations generated by the constant-velocity standard, but in an opposite manner for the two stimulus dimensions. When the comparison glide velocity was faster than the standard, listeners overestimated time change, but underestimated pitch change, whereas when the comparison glide velocity was slower than the standard, listeners underestimated time change, but overestimated pitch change. Perceptual distortions were least evident when the velocities of the standard and comparison glides were matched. Fits of an imputed velocity model further revealed increasingly larger distortions at faster velocities. The present findings provide support for the auditory pitch-motion hypothesis and add to a larger body of work revealing a role for active prediction in human auditory perception.

  3. Spirality: A Noval Way to Measure Spiral Arm Pitch Angle

    NASA Astrophysics Data System (ADS)

    Shields, Douglas W.; Boe, Benjamin; Henderson, Casey L.; Hartley, Matthew; Davis, Benjamin L.; Pour Imani, Hamed; Kennefick, Daniel; Kennefick, Julia D.

    2015-01-01

    We present the MATLAB code Spirality, a novel method for measuring spiral arm pitch angles by fitting galaxy images to spiral templates of known pitch. For a given pitch angle template, the mean pixel value is found along each of typically 1000 spiral axes. The fitting function, which shows a local maximum at the best-fit pitch angle, is the variance of these means. Error bars are found by varying the inner radius of the measurement annulus and finding the standard deviation of the best-fit pitches. Computation time is typically on the order of 2 minutes per galaxy, assuming at least 8 GB of working memory. We tested the code using 128 synthetic spiral images of known pitch. These spirals varied in the number of spiral arms, pitch angle, degree of logarithmicity, radius, SNR, inclination angle, bar length, and bulge radius. A correct result is defined as a result that matches the true pitch within the error bars, with error bars no greater than ±7°. For the non-logarithmic spiral sample, the correct answer is similarly defined, with the mean pitch as function of radius in place of the true pitch. For all synthetic spirals, correct results were obtained so long as SNR > 0.25, the bar length was no more than 60% of the spiral's diameter (when the bar was included in the measurement), the input center of the spiral was no more than 6% of the spiral radius away from the true center, and the inclination angle was no more than 30°. The synthetic spirals were not deprojected prior to measurement. The code produced the correct result for all barred spirals when the measurement annulus was placed outside the bar. Additionally, we compared the code's results against 2DFFT results for 203 visually selected spiral galaxies in GOODS North and South. Among the entire sample, Spirality's error bars overlapped 2DFFT's error bars 64% of the time. For those galaxies in which Source code is available by email request from the primary author.

  4. Absolute pitch and pupillary response: effects of timbre and key color.

    PubMed

    Schlemmer, Kathrin B; Kulke, Franziska; Kuchinke, Lars; Van Der Meer, Elke

    2005-07-01

    The pitch identification performance of absolute pitch possessors has previously been shown to depend on pitch range, key color, and timbre of presented tones. In the present study, the dependence of pitch identification performance on key color and timbre of musical tones was examined by analyzing hit rates, reaction times, and pupillary responses of absolute pitch possessors (n = 9) and nonpossessors (n = 12) during a pitch identification task. Results revealed a significant dependence of pitch identification hit rate but not reaction time on timbre and key color in both groups. Among absolute pitch possessors, peak dilation of the pupil was significantly dependent on key color whereas the effect of timbre was marginally significant. Peak dilation of the pupil differed significantly between absolute pitch possessors and nonpossessors. The observed effects point to the importance of learning factors in the acquisition of absolute pitch.

  5. Joint Japan/U.S. Conference on Adaptive Structures, 2nd, Nagoya, Japan, Nov. 12-14, 1991, Collection of Papers

    NASA Technical Reports Server (NTRS)

    Matsuzaki, Yuji (Editor); Wada, Ben K. (Editor)

    1992-01-01

    The present conference discusses the development status of adaptive structures in Europe and in Japan, the 'Cosmo-Lab' structures/robotics cooperation concept, active-adhesion concepts for in-orbit structural assembly, adaptively controlled truss structures, object-oriented modeling in structural analysis, the control effectiveness and energy efficiency of an active mass damper, a space truss with experimental tendon control, and piezoelectric actuator-based space trusses. Also discussed is the control of resonant frequencies in adaptive structures through prestressing, active control of vortex-excited vibrations of flexible cylindrical structures, shape adjustment of a flexible space antenna reflector, the SDIO Adaptive Structures Program, optimal trajectories of iterative manipulation for space robots, a docking device as an adaptive structure, shape-memory polymers and their hybrid composites, and fuzzy control methods for structural dynamics.

  6. Mesophase pitches, carbon fiber precursors, and carbonized fibers

    SciTech Connect

    Sumner, M.B.; Hettinger, M.P.

    1993-08-24

    A process is described for the production of a stabilized carbon fiber which process comprises: forming a film having a thickness in the range of about 0.025 mm (0.001 in) to about 2.5 mm (0.1 in), of a catalytic pitch; maintaining said film at a temperature in the range of about 327 C to about 427 C and a pressure in the range of about 20 microns of mercury to about 1 atm for a time that is sufficient to produce a heavy isotropic pitch having a softening point in the range of about 127 C to about 288 C, a coking value in the range of about 55 wt % to about 95 wt %, and a maximum mesophase content of 5 vol %; agitating said heavy isotropic pitch while passing an inert gas through said heavy isotropic pitch at a rate of up to about 30 SCFH/1b at a temperature in the range of about 327 C to about 454 C for a time that is sufficient to provide a mesophase pitch having a vol. % of mesophase of at least 60; converting said mesophase pitch into green fibers; and stabilizing for a minimum time ranging from about 14 to about 288 minutes said green fibers with an oxidizing agent while heating said green fibers to a starting temperature of about 41 C to 221 C that is below the glass transition temperature of the mesophase pitch, and thereafter increasing the temperature of said green fiber at a rate of between about 1 C/min and 6 C/min to a final temperature in the range of about 282 C to 343 C to provide a stabilized carbon fiber.

  7. Investigation of flow and microstructure in rheometric and processing flow conditions for liquid crystalline pitch

    NASA Astrophysics Data System (ADS)

    Kundu, Santanu

    The microstructure development within mesophase pitch-based carbon materials depends on the flow history that the pitch is subjected to. Therefore, a fundamental understanding of flow and its influence on the microstructure is required to obtain carbon materials with desired properties. The objective of this research was to investigate the flow and microstructural behavior of a synthetic mesophase pitch (AR-HP) in rheometric and processing flow conditions. In addition, simulation studies were performed to establish a frame work for modeling the flow behavior of this complex material in different flow situations. The steady-shear viscosities obtained from a cone-plate rheometer during increasing rate-sweep experiments exhibited shear-thinning (Region I) and plateau (Region II) responses. However, the slope of the shear-thinning region was only about -0.2, much lower than -0.5 observed in some pitches and liquid-crystalline polymers. This difference could arise from the different molecular constituents of pitches. At higher shear rates, as measured from capillary rheometers, the viscosity values remained almost constant. The transient shear stress responses, as measured from cone-plate rheometer, exhibited nonmonotonic behavior as a function of applied strain at all shear rates and temperatures tested. After rheological experiments, the samples were collected by developing a new experimental protocol for preservation of the sample for microstructural analysis. Microstructural observations obtained from three orthogonal sections, reported for the first time in the literature, indicate that the local maximum in shear stress was due to yielding of initial microstructure. The microstructure became flow oriented with further shearing, and the structure size decreased with increasing shear rates. In addition to high-strain experiments, dynamic experiments were also performed in the linear viscoelastic region where no significant deformation of fluid takes place. The

  8. Influence of pelvis rotation styles on baseball pitching mechanics.

    PubMed

    Wight, Jeff; Richards, James; Hall, Susan

    2004-01-01

    Efficient, sequential timing is essential for upper level pitching. Interestingly, pitchers vary considerably in timing related elements of pitching style including pelvis rotation, arm cocking, stride leg behaviour, and pitch delivery time. The purpose of this study was to determine whether relationships exist among these elements by examining the overall style of pitchers exhibiting different pelvis rotation patterns. Pitching styles were defined by pelvis orientation at the instant of stride foot contact. Pitchers demonstrating a pelvis orientation greater than 30 degrees were designated as 'early rotators', while pitchers demonstrating a pelvis orientation less than 30 degrees were designated as 'late rotators'. Kinematic and temporal differences were associated with the two styles. During the arm cocking phase, early rotators showed significantly greater shoulder external rotation at the instant of stride foot contact, earlier occurrence of maximum pelvis rotation angular velocity, and shorter time taken to complete the phase. However, by the instant of maximum shoulder external rotation, early and late rotators appeared remarkably similar as no significant difference occurred in pelvis and arm orientations. Therefore, it appears that early and late rotators used different methods to achieve similar results, including throwing velocity. Significant differences in throwing arm kinetics were also found for 10 of the 11 measures in the study. As the pelvis assumed a more open position at stride foot contact, maximum kinetic values were found to both decrease in magnitude and occur at an earlier time within the pitch.

  9. Re-examining the upper limit of temporal pitch

    PubMed Central

    Macherey, Olivier; Carlyon, Robert P.

    2015-01-01

    Five normally-hearing listeners pitch-ranked harmonic complexes of different fundamental frequencies (F0s) filtered in three different frequency regions. Harmonics were summed either in sine, alternating sine-cosine (ALT), or pulse-spreading (PSHC) phase. The envelopes of ALT and PSHC complexes repeated at rates of 2F0 and 4F0. Pitch corresponded to those rates at low F0s, but, as F0 increased, there was a range of F0s over which pitch remained constant or dropped. Gammatone-filterbank simulations showed that, as F0 increased and the number of harmonics interacting in a filter dropped, the output of that filter switched from repeating at 2F0 or 4F0 to repeating at F0. A model incorporating this phenomenon accounted well for the data, except for complexes filtered into the highest frequency region (7800-10800 Hz). To account for the data in that region it was necessary to assume either that auditory filters at very high frequencies are sharper than traditionally believed, and/or that the auditory system applies smaller weights to filters whose outputs repeat at high rates. The results also provide new evidence on the highest pitch that can be derived from purely temporal cues, and corroborate recent reports that a complex pitch can be derived from very-high-frequency resolved harmonics. PMID:25480066

  10. Songbirds use spectral shape, not pitch, for sound pattern recognition

    PubMed Central

    Bregman, Micah R.; Patel, Aniruddh D.; Gentner, Timothy Q.

    2016-01-01

    Humans easily recognize “transposed” musical melodies shifted up or down in log frequency. Surprisingly, songbirds seem to lack this capacity, although they can learn to recognize human melodies and use complex acoustic sequences for communication. Decades of research have led to the widespread belief that songbirds, unlike humans, are strongly biased to use absolute pitch (AP) in melody recognition. This work relies almost exclusively on acoustically simple stimuli that may belie sensitivities to more complex spectral features. Here, we investigate melody recognition in a species of songbird, the European Starling (Sturnus vulgaris), using tone sequences that vary in both pitch and timbre. We find that small manipulations altering either pitch or timbre independently can drive melody recognition to chance, suggesting that both percepts are poor descriptors of the perceptual cues used by birds for this task. Instead we show that melody recognition can generalize even in the absence of pitch, as long as the spectral shapes of the constituent tones are preserved. These results challenge conventional views regarding the use of pitch cues in nonhuman auditory sequence recognition. PMID:26811447

  11. Should We Limit Innings Pitched Following Ulnar Collateral Ligament Reconstruction in Major League Baseball Pitchers?

    PubMed Central

    Erickson, Brandon J.; Cvetanovich, Gregory; Bach, Bernard R.; Bush-Joseph, Charles A.; Verma, Nikhil N.; Romeo, Anthony A.

    2016-01-01

    Objectives: Background: Ulnar collateral ligament reconstruction (UCLR) has become a common procedure amongst major league baseball (MLB) pitchers. It is unclear if a limit on innings pitched following UCLR should be instituted to prevent revision UCLR. Purpose: To determine whether the number of innings pitched or number of pitches thrown in the first full season following UCLR, as well as the pitcher’s overall MLB career, correlated with need for a revision UCLR Hypothesis: Number of innings pitched and number of pitches thrown following UCLR will not affect whether a pitcher undergoes a revision UCLR. Methods: Methods: All MLB pitchers between 1974-2015 who pitched at least one full season following UCLR were included. Pitch counts and innings pitched for the first full season following UCLR as well as total pitch count and total innings pitched following UCLR were recorded. Pitch counts and innings pitched were compared amongst players who required revision UCLR and those who did not. Results: Results: Overall, 154 pitchers were included. Of these, 135 pitchers did not require revision UCLR while 19 underwent revision UCLR. No significant difference existed between pitchers who underwent revision UCLR and those who did not in: number of innings pitched in the season following UCLR (p=0.9016), number of pitches thrown in the season following UCLR (p=0.7337), number of innings pitched in the pitcher’s career following UCLR (p=0.6945), and number of pitches thrown in the pitcher’s career following UCLR (p=0.4789). Furthermore, no difference existed in revision rate between pitchers who pitched more or less than 180 innings in the first full season following UCLR (p=0.6678). Conclusion: Conclusion: The number of innings pitched and number of pitches thrown in the first full season as well as over a player’s career following UCLR does not appear to increase a player’s risk of revision UCLR.

  12. Multidisciplinary approach in a water salinity study of the southern San Pitch drainage, Sanpete County, Utah

    NASA Astrophysics Data System (ADS)

    Hardwick, C.

    2015-12-01

    Geologic mapping and geophysical techniques corroborate surface water surveys to identify regions in the subsurface that likely influence San Pitch River salinity in central Utah. Geologic mapping reveals that two members of the Arapien Shale are likely present in the subsurface beneath the areas where saline springs are found. Previous studies specified halite deposits in one member, and indicated the other member is known to contain halite in the general region. A total of 49 unique Transient Electromagnetic Method (TEM) stations were measured in the study area using a ground loop layout. Modeling of TEM data reveals one very shallow conductive body (1 to 10 ohm.m) between desilting basins and the San Pitch River that we interpret to be saline groundwater. A larger, deeper, and more continuous conductive body, observed in the northeast part of the study area, is interpreted as a geologic feature, most likely Arapien Shale. We measured or estimated discharge (flow) at 53 unique locations within streams and from seeps and springs, and estimated water quality (field parameters) at 172 different sites within the flow regime, measuring some sites multiple times during different seasons. Our results show that a 1.6 mile reach of the San Pitch River between the Highway 89 bridge and the confluence with Twelvemile Creek is a major source of salt loading; salt load increases from mostly less than 50 g/s above the bridge to nearly 300 g/s above the confluence. An addition of 80 to 90 g/s salt load from Twelvemile Creek, which carries salt from a 10-acre saline marsh, combines to bring the overall salt load carried by the San Pitch River at a point of irrigation use 3 miles downstream to between approximately 400 g/s in the spring to approximately 650 g/s in autumn. Our combined geologic, geophysical, and hydrologic assessment indicates that the source of salinity in the San Pitch River and Twelvemile Creek is dissolution of salt from the Arapien Shale and its erosional

  13. Electrically tuned photoluminescence in large pitch cholesteric liquid crystal

    SciTech Connect

    Middha, Manju Kumar, Rishi Raina, K. K.

    2014-04-24

    Cholesteric liquid crystals are known as 1-D photonic band gap materials due to their periodic helical supramolecular structure and larger birefringence. Depending upon the helical twisted pitch length, they give the characteristic contrast due to selective Bragg reflections when viewed through the polarizing optical microscope and hence affect the electro-optic properties. So the optimization of chiral dopant concentration in nematic liquid crystal leads to control the transmission of polarized light through the microscope. Hence transmission based polarizing optical microscope is used for the characterization of helical pitch length in the optical texture. The unwinding of helical pitch was observed with the application of electric field which affects the intensity of photoluminescence.

  14. Preparation of activated carbons from bituminous coal pitches

    NASA Astrophysics Data System (ADS)

    Gañan, J.; González-García, C. M.; González, J. F.; Sabio, E.; Macías-García, A.; Díaz-Díez, M. A.

    2004-11-01

    High-porosity carbons were prepared from bituminous coal pitches by combining chemical and physical activation. The chemical activation process consisted of potassium hydroxide impregnation followed by carbonization in nitrogen atmosphere. The effect of the KOH impregnation ratio on the surface area and pore volumes evolution of the carbons derived from mesophase pitch was studied. The optimum KOH:pitch ratio was fixed to realize a physical activation process in order to increase the textural parameters of the KOH-activated carbons. Physical activation was performed by carbonizing the KOH-activated carbons followed by gasifying with air. The influence of the carbonization temperature and the residence time of the gasification with air were explored to optimize those preparation parameters.

  15. An advanced pitch change mechanism incorporating a hybrid traction drive

    NASA Technical Reports Server (NTRS)

    Steinetz, B. M.; Sargisson, D. F.; White, G.; Loewenthal, S. H.

    1984-01-01

    A design of a propeller pitch control mechanism is described that meets the demanding requirements of a high-power, advanced turboprop. In this application, blade twisting moment torque can be comparable to that of the main reduction gearbox output: precise pitch control, reliability and compactness are all at a premium. A key element in the design is a compact, high-ratio hybrid traction drive which offers low torque ripple and high torsional stiffness. The traction drive couples a high speed electric motor/alternator unit to a ball screw that actuates the blade control links. The technical merits of this arrangement and the performance characteristics of the traction drive are discussed. Comparisons are made to the more conventional pitch control mechanisms.

  16. Characterization of Vortex Development on a Pitching Plate

    NASA Astrophysics Data System (ADS)

    Wabick, Kevin; Buchholz, James

    2016-11-01

    The formation and evolution of leading-edge vortices (LEVs) is ubiquitous on a broad range of aerodynamic structures and natural fliers, and can have a significant impact on aerodynamic loads. The formation of LEVs is considered on a pitching flat plate at a chord-based Reynolds number of 104 with varying dimensionless pitch rate through characterization of the sources and sinks of vorticity that contribute to their growth and evolution. The effect of pitch rate is examined, and the flow field evolution and measured fluxes of vorticity are compared to prior measurements on a purely plunging plate, to isolate the effects of rotation on the factors contributing to vortex strength and development. This work was supported by the Air Force Office of Scientific Research through Grant Number FA9550-16-1-0107.

  17. Target pitch angle for the microburst escape maneuver

    NASA Technical Reports Server (NTRS)

    Mulgund, Sandeep S.

    1991-01-01

    The objective of this study was to investigate the constant pitch attitude strategy as a possible non-precision maneuver for recovery from inadvertent wind shear encounters. The Wind Shear Training Aid published by the FAA recommends that upon encountering a severe wind shear, the pilot should apply maximum thrust and rotate the aircraft to an initial pitch target angle of 15 degrees. The 15 degrees target was identified through rigorous analyses using six-degree-of-freedom flight simulators and microburst models representative of actual accident cases. It was found that 15 degrees was an effective target for a wide range of shears, and was generally applicable to most jet transports. This work was undertaken to examine the issue of recovery performance in wind shear of other classes of aircraft - notably turboprop commuters and propeller-driven general aviation planes. It should be possible to postulate a target pitch angle (TPA) for such aircraft, as well.

  18. Electrically tuned photoluminescence in large pitch cholesteric liquid crystal

    NASA Astrophysics Data System (ADS)

    Middha, Manju; Kumar, Rishi; Raina, K. K.

    2014-04-01

    Cholesteric liquid crystals are known as 1-D photonic band gap materials due to their periodic helical supramolecular structure and larger birefringence. Depending upon the helical twisted pitch length, they give the characteristic contrast due to selective Bragg reflections when viewed through the polarizing optical microscope and hence affect the electro-optic properties. So the optimization of chiral dopant concentration in nematic liquid crystal leads to control the transmission of polarized light through the microscope. Hence transmission based polarizing optical microscope is used for the characterization of helical pitch length in the optical texture. The unwinding of helical pitch was observed with the application of electric field which affects the intensity of photoluminescence.

  19. Unsteady transition measurements on a pitching three-dimensional wing

    NASA Technical Reports Server (NTRS)

    Lorber, Peter F.; Carta, Franklin O.

    1992-01-01

    Boundary layer transition measurements were made during an experimental study of the aerodynamics of a rectangular wing undergoing unsteady pitching motions. The wing was tested at chordwise Mach numbers between 0.2 and 0.6, at sweep angles of 0, 15, and 30 deg, and for steady state, sinusoidal, and constant pitch rate motions. The model was scaled to represent a full size helicopter rotor blade, with chord Reynolds numbers between 2 and 6 x 10(exp 6). Sixteen surface hot-film gages were located along three spanwise stations: 0.08, 0.27, and 0.70 chords from the wing tip. Qualitative heat transfer information was obtained to identify the unsteady motion of the point of transition to turbulence. In combination with simultaneous measurements of the unsteady surface pressure distributions, the results illustrate the effects of compressibility, sweep, pitch rate, and proximity to the wing tip on the transition and relaminarization locations.

  20. Absolute memory for musical pitch: evidence from the production of learned melodies.

    PubMed

    Levitin, D J

    1994-10-01

    Evidence for the absolute nature of long-term auditory memory is provided by analyzing the production of familiar melodies. Additionally, a two-component theory of absolute pitch is presented, in which this rare ability is conceived as consisting of a more common ability, pitch memory, and a separate, less common ability, pitch labeling. Forty-six subjects sang two different popular songs, and their productions were compared with the actual pitches used in recordings of those songs. Forty percent of the subjects sang the correct pitch on at least one trial; 12% of the subjects hit the correct pitch on both trials, and 44% came within two semitones of the correct pitch on both trials. The results show a convergence with previous studies on the stability of auditory imagery and latent absolute pitch ability; the results further suggest that individuals might possess representations of pitch that are more stable and accurate than previously recognized.

  1. Changes in baseball batters' brain activity with increased pitch choice.

    PubMed

    Ryu, Kwangmin; Kim, Jingu; Ali, Asif; Kim, Woojong; Radlo, Steven J

    2015-09-01

    In baseball, one factor necessary for batters to decide whether to swing or not depends on what type of pitch is thrown. Oftentimes batters will look for their pitch (i.e., waiting for a fastball). In general, when a pitcher has many types of pitches in his arsenal, batters will have greater difficulty deciding upon the pitch thrown. Little research has been investigated the psychophysiology of a batters decision-making processes. Therefore, the primary purpose of this study was to determine how brain activation changes according to an increase in the number of alternatives (NA) available. A total of 15 male college baseball players participated in this study. The stimuli used in this experiment were video clips of a right-handed pitcher throwing fastball, curve, and slider pitches. The task was to press a button after selecting the fastball as the target stimulus from two pitch choices (fastball and curve), and then from three possibilities (fastball, curve, and slider). Functional and anatomic image scanning magnetic resonance imaging (MRI) runs took 4 and 5[Formula: see text]min, respectively. According to our analysis, the right precentral gyrus, left medial frontal gyrus, and right fusiform gyrus were activated when the NA was one. The supplementary motor areas (SMA) and primary motor cortex were activated when there were two alternatives to choose from and the inferior orbitofrontal gyrus was specifically activated with three alternatives. Contrary to our expectations, the NA was not a critical factor influencing the activation of related decision making areas when the NA was compared against one another. These findings highlight that specific brain areas related to decision making were activated as the NA increased.

  2. Yaw and pitch visual-vestibular interaction in weightlessness

    NASA Technical Reports Server (NTRS)

    Clement, G.; Wood, S. J.; Reschke, M. F.; Berthoz, A.; Igarashi, M.

    1999-01-01

    Both yaw and pitch visual-vestibular interactions at two separate frequencies of chair rotation (0.2 and 0.8 Hz) in combination with a single velocity of optokinetic stimulus (36 degrees/s) were used to investigate the effects of sustained weightlessness on neural strategies adopted by astronaut subjects to cope with the stimulus rearrangement of spaceflight. Pitch and yaw oscillation in darkness at 0.2 and 0.8 Hz without optokinetic stimulation, and constant velocity linear optokinetic stimulation at 18, 36, and 54 degrees/s presented relative to the head with the subject stationary, were used as controls for the visual-vestibular interactions. The results following 8 days of space flight showed no significant changes in: (1) either the horizontal and vertical vestibulo-ocular reflex (VOR) gain, phase, or bias; (2) the yaw visual-vestibular response (VVR); or (3) the horizontal or vertical optokinetic (OKN) slow phase velocity (SPV). However, significant changes were observed: (1) when during pitch VVR at 0.2 Hz late inflight, the contribution of the optokinetic input to the combined oculomotor response was smaller than during the stationary OKN SPV measurements, followed by an increased contribution during the immediate postflight testing; and (2) when during pitch VVR at 0.8 Hz, the component of the combined oculomotor response due to the underlying vertical VOR was more efficiently suppressed early inflight and less suppressed immediately postflight compared with preflight observations. The larger OKN response during pitch VVR at 0.2 Hz and the better suppression of VOR during pitch VVR at 0.8 Hz postflight are presumably due to the increased role of vision early inflight and immediately after spaceflight, as previously observed in various studies. These results suggest that the subjects adopted a neural strategy to structure their spatial orientation in weightlessness by reweighting visual, otolith, and perhaps tactile/somatic signals.

  3. Abnormal Pitch Perception Produced by Cochlear Implant Stimulation

    PubMed Central

    Zeng, Fan-Gang; Tang, Qing; Lu, Thomas

    2014-01-01

    Contemporary cochlear implants with multiple electrode stimulation can produce good speech perception but poor music perception. Hindered by the lack of a gold standard to quantify electric pitch, relatively little is known about the nature and extent of the electric pitch abnormalities and their impact on cochlear implant performance. Here we overcame this obstacle by comparing acoustic and electric pitch perception in 3 unilateral cochlear-implant subjects who had functionally usable acoustic hearing throughout the audiometric frequency range in the non-implant ear. First, to establish a baseline, we measured and found slightly impaired pure tone frequency discrimination and nearly perfect melody recognition in all 3 subjects’ acoustic ear. Second, using pure tones in the acoustic ear to match electric pitch induced by an intra-cochlear electrode, we found that the frequency-electrode function was not only 1–2 octaves lower, but also 2 times more compressed in frequency range than the normal cochlear frequency-place function. Third, we derived frequency difference limens in electric pitch and found that the equivalent electric frequency discrimination was 24 times worse than normal-hearing controls. These 3 abnormalities are likely a result of a combination of broad electric field, distant intra-cochlear electrode placement, and non-uniform spiral ganglion cell distribution and survival, all of which are inherent to the electrode-nerve interface in contemporary cochlear implants. Previous studies emphasized on the “mean” shape of the frequency-electrode function, but the present study indicates that the large “variance” of this function, reflecting poor electric pitch discriminability, is the main factor limiting contemporary cochlear implant performance. PMID:24551131

  4. Unique Pitch Evolution in the Smectic -C-alpha* Phase

    SciTech Connect

    Liu,Z.; McCoy, B.; Wang, S.; Pindak, R.; Caliebe, W.; Barois, P.; Fernandes, P.; Nguyen, H.; Hsu, C.; Wang, .

    2007-01-01

    Employing resonant x-ray diffraction, we observed unique pitch evolutions in the smectic-C{alpha}* phase in mixtures of two antiferroelectric liquid crystals. Our results show that the pitch in this phase continuously evolves across 4 layers, contradicting a theoretical model that predicts that the smectic-C{sub FI2}* phase intervenes in the smectic-C{alpha}* phase. The phase sequences we found can be explained by another model that includes one type of long-range interaction among smectic layers.

  5. Ratier Metal Propeller with Pitch Variable in Flight

    NASA Technical Reports Server (NTRS)

    Leglise, Pierre

    1930-01-01

    One of the serious sources of difficulties in variable pitch propellers is the turning moment or torque due to the centrifugal force which tends to bring the mean plane of the blades into the plane of rotation. This moment, which is found elsewhere only in propellers with removable blades, is so great that the aerodynamic forces, as regards their effect on the torsion, become entirely negligible in comparison with it. This report presents the Ratier Company's solution to changing the pitch of airplane propellers.

  6. Repetition Pitch glide from the step pyramid at Chichen Itza.

    PubMed

    Bilsen, Frans A

    2006-08-01

    Standing at the foot of the Mayan step pyramid at Chichen Itza in Mexico, one can produce a pitchy "chirp" echo by handclapping. As exposed by Declercq et al. [J. Acoust. Soc. Am. 116, 3328-3335 (2004)], an acoustic model based on optical Bragg diffraction at a periodic structure cannot explain satisfactorily the chirp-echo sonogram. Alternatively, considering the echo as a sequence of reflections, and given the dimensions of the pyramid and source-receiver position, the chirp is predicted correctly as a Repetition Pitch glide of which the pitch height is continuously decreasing within 177 ms from 796 to 471 Hz-equivalent.

  7. Voice Pitch Elicited Frequency Following Response in Chinese Elderlies

    PubMed Central

    Wang, Shuo; Hu, Jiong; Dong, Ruijuan; Liu, Dongxin; Chen, Jing; Musacchia, Gabriella; Liu, Bo

    2016-01-01

    Background: Perceptual and electrophysiological studies have found reduced speech discrimination in quiet and noisy environment, delayed neural timing, decreased neural synchrony, and decreased temporal processing ability in elderlies, even those with normal hearing. However, recent studies have also demonstrated that language experience and auditory training enhance the temporal dynamics of sound encoding in the auditory brainstem response (ABR). The purpose of this study was to explore the pitch processing ability at the brainstem level in an aging population that has a tonal language background. Method: Mandarin speaking younger (n = 12) and older (n = 12) adults were recruited for this study. All participants had normal audiometric test results and normal suprathreshold click-evoked ABR. To record frequency following responses (FFRs) elicited by Mandarin lexical tones, two Mandarin Chinese syllables with different fundamental frequency pitch contours (Flat Tone and Falling Tone) were presented at 70 dB SPL. Fundamental frequencies (f0) of both the stimulus and the responses were extracted and compared to individual brainstem responses. Two indices were used to examine different aspects of pitch processing ability at the brainstem level: Pitch Strength and Pitch Correlation. Results: Lexical tone elicited FFR were overall weaker in the older adult group compared to their younger adult counterpart. Measured by Pitch Strength and Pitch Correlation, statistically significant group differences were only found when the tone with a falling f0 (Falling Tone) were used as the stimulus. Conclusion: Results of this study demonstrated that in a tonal language speaking population, pitch processing ability at the brainstem level of older adults are not as strong and robust as their younger counterparts. Findings of this study are consistent with previous reports on brainstem responses of older adults whose native language is English. On the other hand, lexical tone elicited

  8. Dynamically Tuned Blade Pitch Links for Vibration Reduction

    NASA Technical Reports Server (NTRS)

    Milgram, Judah; Chopra, Inderjit; Kottapalli, Sesi

    1994-01-01

    A passive vibration reduction device in which the conventional main rotor blade pitch link is replaced by a spring/damper element is investigated using a comprehensive rotorcraft analysis code. A case study is conducted for a modern articulated helicopter main rotor. Correlation of vibratory pitch link loads with wind tunnel test data is satisfactory for lower harmonics. Inclusion of unsteady aerodynamics had little effect on the correlation. In the absence of pushrod damping, reduction in pushrod stiffness from the baseline value had an adverse effect on vibratory hub loads in forward flight. However, pushrod damping in combination with reduced pushrod stiffness resulted in modest improvements in fixed and rotating system hub loads.

  9. Dynamic Stall of a Pitching and Horizontally Oscillating Airfoil

    NASA Astrophysics Data System (ADS)

    Martinat, G.; Braza#, M.; Harran, G.; Sevrain, A.; Tzabiras, G.; Hoarau, Y.; Favier, D.

    This paper provides a study of the dynamic stall of a pitching airfoil and of a pitching and horizontally oscillating airfoil at 105 Reynolds number by means of nbumerical simulation. Three turbulence models are compared in both cases: URANS Spalart-Allmaras model, URANS k—ɛ Chien model and URANS=OES model. results are in accordance with experimental data but spalart model seems to be too much viscous to provide good results and overpredict hysteresis cycle observed where URANS=OES seems to be viscousless. URANS k—ɛ Chien model is providing the best results.

  10. Auditory adaptation in voice perception.

    PubMed

    Schweinberger, Stefan R; Casper, Christoph; Hauthal, Nadine; Kaufmann, Jürgen M; Kawahara, Hideki; Kloth, Nadine; Robertson, David M C; Simpson, Adrian P; Zäske, Romi

    2008-05-06

    Perceptual aftereffects following adaptation to simple stimulus attributes (e.g., motion, color) have been studied for hundreds of years. A striking recent discovery was that adaptation also elicits contrastive aftereffects in visual perception of complex stimuli and faces [1-6]. Here, we show for the first time that adaptation to nonlinguistic information in voices elicits systematic auditory aftereffects. Prior adaptation to male voices causes a voice to be perceived as more female (and vice versa), and these auditory aftereffects were measurable even minutes after adaptation. By contrast, crossmodal adaptation effects were absent, both when male or female first names and when silently articulating male or female faces were used as adaptors. When sinusoidal tones (with frequencies matched to male and female voice fundamental frequencies) were used as adaptors, no aftereffects on voice perception were observed. This excludes explanations for the voice aftereffect in terms of both pitch adaptation and postperceptual adaptation to gender concepts and suggests that contrastive voice-coding mechanisms may routinely influence voice perception. The role of adaptation in calibrating properties of high-level voice representations indicates that adaptation is not confined to vision but is a ubiquitous mechanism in the perception of nonlinguistic social information from both faces and voices.

  11. A study on the effect of heat treatment temperature on mesophase development in coal tar pitch

    NASA Astrophysics Data System (ADS)

    Soni, Neha; Shah, Raviraj K.; Shrivastava, Rakesh; Datar, Manoj

    2013-06-01

    In the present study, a zero quinoline insoluble (QI) isotropic coal tar pitch was taken for the preparation of mesophase pitch. The pitch was heated in inert atmosphere at different heat treatment temperatures keeping same heating rate and soaking time to study the formation, growth and coalescence of mesophase spheres in the pitch. Such pitches were characterized for insoluble content (QI & TI), mesophase content, sulphur content, weight loss in inert atmosphere, softening point, coking value (CVC), C/H ratio etc. Results show that the insoluble content (QI & TI) and mesophase content of pitch increase with increase of heat treatment temperature.

  12. Vehicle Engine Classification Using Spectral Tone-Pitch Vibration Indexing and Neural Network.

    PubMed

    Wei, Jie; Vongsy, Karmon; Mendoza-Schrock, Olga; Liu, Chi-Him

    2014-07-01

    As a non-invasive and remote sensor, the Laser Doppler Vibrometer (LDV) has found a broad spectrum of applications in various areas such as civil engineering, biomedical engineering, and even security and restoration within art museums. LDV is an ideal sensor to detect threats earlier and provide better protection to society, which is of utmost importance to military and law enforcement institutions. However, the use of LDV in situational surveillance, in particular vehicle classification, is still in its infancy due to the lack of systematic investigations on its behavioral properties. In this work, as a result of the pilot project initiated by Air Force Research Laboratory, the innate features of LDV data from many vehicles are examined, beginning with an investigation of feature differences compared to human speech signals. A spectral tone-pitch vibration indexing scheme is developed to capture the engine's periodic vibrations and the associated fundamental frequencies over the vehicles' surface. A two-layer feed-forward neural network with 20 intermediate neurons is employed to classify vehicles' engines based on their spectral tone-pitch indices. The classification results using the proposed approach over the complete LDV dataset collected by the project are exceedingly encouraging; consistently higher than 96% accuracies are attained for all four types of engines collected from this project.

  13. Independent Blade Pitch Controller Design for a Three-Bladed Turbine Using Disturbance Accommodating Control: Preprint

    SciTech Connect

    Wang, Na; Wright, Alan D.; Johnson, Kathryn E.

    2016-07-29

    Two independent pitch controllers (IPCs) based on the disturbance accommodating control (DAC) algorithm are designed for the three-bladed Controls Advanced Research Turbine to regulate rotor speed and to mitigate blade root flapwise bending loads in above-rated wind speed. One of the DAC-based IPCs is designed based on a transformed symmetrical-asymmetrical (TSA) turbine model, with wind disturbances being modeled as a collective horizontal component and an asymmetrical linear shear component. Another DAC-based IPC is designed based on a multiblade coordinate (MBC) transformed turbine model, with a horizontal component and a vertical shear component being modeled as step waveform disturbance. Both of the DAC-based IPCs are found via a regulation equation solved by Kronecker product. Actuator dynamics are considered in the design processes to compensate for actuator phase delay. The simulation study shows the effectiveness of the proposed DAC-based IPCs compared to a proportional-integral (PI) collective pitch controller (CPC). Improvement on rotor speed regulation and once-per-revolution and twice-per-revolution load reductions has been observed in the proposed IPC designs.

  14. Independent Blade Pitch Controller Design for a Three-Bladed Turbine Using Disturbance Accommodating Control

    SciTech Connect

    Wang, Na; Wright, Alan D.; Johnson, Kathryn E.

    2016-08-01

    Two independent pitch controllers (IPCs) based on the disturbance accommodating control (DAC) algorithm are designed for the three-bladed Controls Advanced Research Turbine to regulate rotor speed and to mitigate blade root flapwise bending loads in above-rated wind speed. One of the DAC-based IPCs is designed based on a transformed symmetrical-asymmetrical (TSA) turbine model, with wind disturbances being modeled as a collective horizontal component and an asymmetrical linear shear component. Another DAC-based IPC is designed based on a multiblade coordinate (MBC) transformed turbine model, with a horizontal component and a vertical shear component being modeled as step waveform disturbance. Both of the DAC-based IPCs are found via a regulation equation solved by Kronecker product. Actuator dynamics are considered in the design processes to compensate for actuator phase delay. The simulation study shows the effectiveness of the proposed DAC-based IPCs compared to a proportional-integral (PI) collective pitch controller (CPC). Improvement on rotor speed regulation and once-per-revolution and twice-per-revolution load reductions has been observed in the proposed IPC designs.

  15. Vehicle Engine Classification Using Spectral Tone-Pitch Vibration Indexing and Neural Network*

    PubMed Central

    Wei, Jie; Vongsy, Karmon; Mendoza-Schrock, Olga; Liu, Chi-Him

    2015-01-01

    As a non-invasive and remote sensor, the Laser Doppler Vibrometer (LDV) has found a broad spectrum of applications in various areas such as civil engineering, biomedical engineering, and even security and restoration within art museums. LDV is an ideal sensor to detect threats earlier and provide better protection to society, which is of utmost importance to military and law enforcement institutions. However, the use of LDV in situational surveillance, in particular vehicle classification, is still in its infancy due to the lack of systematic investigations on its behavioral properties. In this work, as a result of the pilot project initiated by Air Force Research Laboratory, the innate features of LDV data from many vehicles are examined, beginning with an investigation of feature differences compared to human speech signals. A spectral tone-pitch vibration indexing scheme is developed to capture the engine’s periodic vibrations and the associated fundamental frequencies over the vehicles’ surface. A two-layer feed-forward neural network with 20 intermediate neurons is employed to classify vehicles’ engines based on their spectral tone-pitch indices. The classification results using the proposed approach over the complete LDV dataset collected by the project are exceedingly encouraging; consistently higher than 96% accuracies are attained for all four types of engines collected from this project. PMID:26788417

  16. The effect of the reinforcing carbon on the microstructure of pitch-based granular composites.

    PubMed

    Méndez, A; Santamaría, R; Granda, M; Menéndez, R

    2003-02-01

    Carbon composites were prepared with four pitches (a commercial impregnating coal-tar pitch, two thermally treated pitches and an air-blown pitch) and four granular carbons (anthracite, graphite, green petroleum coke and foundry coke). Granular carbon/pitch proportions were optimized for each composite and differed in the characteristics of the single components. Interactions of the pitch with the granular carbons during pyrolysis and their subsequent effects on the microstructure of the final composite were monitored by light microscopy. The results show that the light texture of the matrix and the porosity of the composite depend not only on the chemical composition of the pitch but also on the specific granular carbon used as reinforcing material. The same pitch may generate different light textures depending on the characteristics of the carbon. Composites from thermally treated pitches and graphite show highly ordered matrices orientated in the direction of graphite planes. Graphite particles seem to exert a huge influence on mesophase development during the pyrolysis of the treated pitches, affecting not only the orientation of the mesophase, but also reducing the rate of mesophase formation. On the other hand, when green petroleum coke is used with the thermally treated pitches, matrices show a small size light texture, due to the high reactivity of the pitch in the presence of this granular carbon. The porosity of the composites is controlled by both the pitch and the granular carbon.

  17. 18. LOOKING SOUTH AT STEEPLY PITCHED, GABLED ROOF. THE UPPER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. LOOKING SOUTH AT STEEPLY PITCHED, GABLED ROOF. THE UPPER DORMERS PROVIDE LIGHT IN THE LOBBY AND THE LOWER DORMERS OPEN INTO SOME OF THE ORIGINAL GUEST ROOMS IN THE INN. (TAKEN FROM CHERRY- PICKER) - Old Faithful Inn, 900' northeast of Snowlodge & 1050' west of Old Faithful Lodge, Lake, Teton County, WY

  18. Bat Dynamics of Female Fast Pitch Softball Batters.

    ERIC Educational Resources Information Center

    Messier, Stephen P.; Owen, Marjorie G.

    1984-01-01

    Female fast pitch softball batters served in an examination of the dynamic characteristics of the bat during the swing through the use of three-dimensional cinematographic analysis techniques. These results were compared with those from previous studies of baseball batting. Findings are listed. (Author/DF)

  19. Spirality: A Noval Way to Measure Spiral Arm Pitch Angle

    NASA Astrophysics Data System (ADS)

    Shields, Douglas; Arkansas Galaxy Evolution Survey

    2017-01-01

    We present the MATLAB code Spirality, a novel method for measuring spiral arm pitch angles by fitting galaxy images to spiral templates of known pitch. Computation time is typically on the order of 2 minutes per galaxy, assuming 8 GB of working memory. We tested the code using 117 synthetic spiral images with known pitches, varying both the spiral properties and the input parameters. The code yielded correct results for all synthetic spirals with galaxy-like properties. We also compared the code’s results to two-dimensional Fast Fourier Transform (2DFFT) measurements for the sample of nearby galaxies defined by DMS PPak. Spirality’s error bars overlapped 2DFFT’s error bars for 26 of the 30 galaxies. The two methods’ agreement correlates strongly with galaxy radius in pixels and also with i-band magnitude, but not with redshift, a result that is consistent with at least some galaxies’ spiral structure being fully formed by z=1.2, beyond which there are few galaxies in our sample. We also analyze apparent spiral structure of three galaxies beyond z=2. The Spirality code package also includes GenSpiral, which produces FITS images of synthetic spirals, and SpiralArmCount, which uses a one-dimensional Fast Fourier Transform to count the spiral arms of a galaxy after its pitch is determined.

  20. Process for tertiary oil recovery using tall oil pitch

    DOEpatents

    Radke, C.J.

    1983-07-25

    A process and compositions for enhancing the recovery of acid crudes are disclosed. The process involves injecting caustic solutions into the reservoir to maintain a pH of 11 to 13. The fluid contains an effective amount of multivalent cation for inhibiting alkaline silica dissolution with the reservoir. A tall oil pitch soap is added as a polymeric mobility control agent. (DMC)

  1. Perceptual Grouping Affects Pitch Judgments across Time and Frequency

    ERIC Educational Resources Information Center

    Borchert, Elizabeth M. O.; Micheyl, Christophe; Oxenham, Andrew J.

    2011-01-01

    Pitch, the perceptual correlate of fundamental frequency (F0), plays an important role in speech, music, and animal vocalizations. Changes in F0 over time help define musical melodies and speech prosody, while comparisons of simultaneous F0 are important for musical harmony, and for segregating competing sound sources. This study compared…

  2. Symmetric interactions and interference between pitch and timbre.

    PubMed

    Allen, Emily J; Oxenham, Andrew J

    2014-03-01

    Variations in the spectral shape of harmonic tone complexes are perceived as timbre changes and can lead to poorer fundamental frequency (F0) or pitch discrimination. Less is known about the effects of F0 variations on spectral shape discrimination. The aims of the study were to determine whether the interactions between pitch and timbre are symmetric, and to test whether musical training affects listeners' ability to ignore variations in irrelevant perceptual dimensions. Difference limens (DLs) for F0 were measured with and without random, concurrent, variations in spectral centroid, and vice versa. Additionally, sensitivity was measured as the target parameter and the interfering parameter varied by the same amount, in terms of individual DLs. Results showed significant and similar interference between pitch (F0) and timbre (spectral centroid) dimensions, with upward spectral motion often confused for upward F0 motion, and vice versa. Musicians had better F0DLs than non-musicians on average, but similar spectral centroid DLs. Both groups showed similar interference effects, in terms of decreased sensitivity, in both dimensions. Results reveal symmetry in the interference effects between pitch and timbre, once differences in sensitivity between dimensions and subjects are controlled. Musical training does not reliably help to overcome these effects.

  3. Electrochemical Migration of Fine-Pitch Nanopaste Ag Interconnects

    NASA Astrophysics Data System (ADS)

    Tsou, Chia-Hung; Liu, Kai-Ning; Lin, Heng-Tien; Ouyang, Fan-Yi

    2016-12-01

    With the development of intelligent electronic products, usage of fine-pitch interconnects has become mainstream in high performance electronic devices. Electrochemical migration (ECM) of interconnects would be a serious reliability problem under temperature, humidity and biased voltage environments. In this study, ECM behavior of nanopaste Ag interconnects with pitch size from 20 μm to 50 μm was evaluated by thermal humidity bias (THB) and water drop (WD) tests with deionized water through in situ leakage current-versus-time (CVT) curve. The results indicate that the failure time of ECM in fine-pitch samples occurs within few seconds under WD testing and it increases with increasing pitch size. The microstructure examination indicated that intensive dendrite formation of Ag through the whole interface was found to bridge the two electrodes. In the THB test, the CVT curve exhibited two stages, incubation and ramp-up; failure time of ECM was about 173.7 min. In addition, intensive dendrite formation was observed only at the protrusion of the Ag interconnects due to the concentration of the electric field at the protrusion of the Ag interconnects.

  4. Development in Children's Interpretation of Pitch Cues to Emotions

    ERIC Educational Resources Information Center

    Quam, Carolyn; Swingley, Daniel

    2012-01-01

    Young infants respond to positive and negative speech prosody (A. Fernald, 1993), yet 4-year-olds rely on lexical information when it conflicts with paralinguistic cues to approval or disapproval (M. Friend, 2003). This article explores this surprising phenomenon, testing one hundred eighteen 2- to 5-year-olds' use of isolated pitch cues to…

  5. Phonological Processing in Adults with Deficits in Musical Pitch Recognition

    ERIC Educational Resources Information Center

    Jones, Jennifer L.; Lucker, Jay; Zalewski, Christopher; Brewer, Carmen; Drayna, Dennis

    2009-01-01

    We identified individuals with deficits in musical pitch recognition by screening a large random population using the Distorted Tunes Test (DTT), and enrolled individuals who had DTT scores in the lowest 10th percentile, classified as tune deaf. We examined phonological processing abilities in 35 tune deaf and 34 normal control individuals. Eight…

  6. Shoulder muscle firing patterns during the windmill softball pitch.

    PubMed

    Maffet, M W; Jobe, F W; Pink, M M; Brault, J; Mathiyakom, W

    1997-01-01

    The purpose of this study was to describe the activity of eight shoulder muscles during the windmill fast-pitch softball throw. Ten collegiate female pitchers were analyzed with intramuscular electromyography, high-speed cinematography, and motion analysis. The supraspinatus muscle fired maximally during arm elevation from the 6 to 3 o'clock position phase, centralizing the humeral head within the glenoid. The posterior deltoid and teres minor muscles acted maximally from the 3 to 12 o'clock position phase to continue arm elevation and externally rotate the humerus. The pectoralis major muscle accelerated the arm from the 12 o'clock position to ball release phase. The serratus anterior muscle characteristically acted to position the scapula for optimal glenohumeral congruency, and the subscapularis muscle functioned as an internal rotator and to protect the anterior capsule. Although the windmill softball pitch is overtly different from the baseball pitch, several surprising similarities were revealed. The serratus anterior and pectoralis major muscles work in synchrony and seem to have similar functions in both pitches. Although the infraspinatus and teres minor muscles are both posterior cuff muscles, they are characteristically uncoupled during the 6 to 3 o'clock position phase, with the infraspinatus muscle acting more independently below 90 degrees. Subscapularis muscle activity seems important in dynamic anterior glenohumeral stabilization and as an internal rotator in both the baseball and softball throws.

  7. Effects of pitch, level, and tactile cues on speech segregation

    NASA Astrophysics Data System (ADS)

    Drullman, Rob; Bronkhorst, Adelbert W.

    2003-04-01

    Sentence intelligibility for interfering speech was investigated as a function of level difference, pitch difference, and presence of tactile support. A previous study by the present authors [J. Acoust. Soc. Am. 111, 2432-2433 (2002)] had shown a small benefit of tactile support in the speech-reception threshold measured against a background of one to eight competing talkers. The present experiment focused on the effects of informational and energetic masking for one competing talker. Competing speech was obtained by manipulating the speech of the male target talker (different sentences). The PSOLA technique was used to increase the average pitch of competing speech by 2, 4, 8, or 12 semitones. Level differences between target and competing speech ranged from -16 to +4 dB. Tactile support (B&K 4810 shaker) was given to the index finger by presenting the temporal envelope of the low-pass-filtered speech (0-200 Hz). Sentences were presented diotically and the percentage of correctly perceived words was measured. Results show a significant overall increase in intelligibility score from 71% to 77% due to tactile support. Performance improves monotonically with increasing pitch difference. Louder target speech generally helps perception, but results for level differences are considerably dependent on pitch differences.

  8. The Relationship between Pitch and Space in Congenital Amusia

    ERIC Educational Resources Information Center

    Williamson, Victoria J.; Cocchini, Gianna; Stewart, Lauren

    2011-01-01

    Congenital amusia manifests as a lifelong difficulty in making sense of musical sound. The extent to which this disorder is accompanied by deficits in visuo-spatial processing is an important question, bearing on the issue of whether pitch processing draws on supramodal spatial representations. The present study assessed different aspects of…

  9. Perceptual hysteresis in the judgment of auditory pitch shift.

    PubMed

    Chambers, Claire; Pressnitzer, Daniel

    2014-07-01

    Perceptual hysteresis can be defined as the enduring influence of the recent past on current perception. Here, hysteresis was investigated in a basic auditory task: pitch comparisons between successive tones. On each trial, listeners were presented with pairs of tones and asked to report the direction of subjective pitch shift, as either "up" or "down." All tones were complexes known as Shepard tones (Shepard, 1964), which comprise several frequency components at octave multiples of a base frequency. The results showed that perceptual judgments were determined both by stimulus-related factors (the interval ratio between the base frequencies within a pair) and by recent context (the intervals in the two previous trials). When tones were presented in ordered sequences, for which the frequency interval between tones was varied in a progressive manner, strong hysteresis was found. In particular, ambiguous stimuli that led to equal probabilities of "up" and "down" responses within a randomized context were almost fully determined within an ordered context. Moreover, hysteresis did not act on the direction of the reported pitch shift, but rather on the perceptual representation of each tone. Thus, hysteresis could be observed within sequences in which listeners varied between "up" and "down" responses, enabling us to largely rule out confounds related to response bias. The strength of the perceptual hysteresis observed suggests that the ongoing context may have a substantial influence on fundamental aspects of auditory perception, such as how we perceive the changes in pitch between successive sounds.

  10. Advancement in 17-micron pixel pitch uncooled focal plane arrays

    NASA Astrophysics Data System (ADS)

    Li, Chuan; Skidmore, George; Howard, Christopher; Clarke, Elwood; Han, C. J.

    2009-05-01

    This paper provides an update of 17 micron pixel pitch uncooled microbolometer development at DRS. Since the introduction of 17 micron pitch 640x480 focal plane arrays (FPAs) in 2006, significant progress has been made in sensor performance and manufacturing processes. The FPAs are now in initial production with an FPA noise equivalent temperature difference (NETD), detector thermal time constant, and pixel operability equivalent or better than that of the current 25 micron pixel pitch production FPAs. NETD improvement was achieved without compromising detector thermal response or thermal time constant by simultaneous reduction in bolometer heat capacity and thermal conductance. In addition, the DRS unique "umbrella" microbolometer cavities were optically tuned to optimize detector radiation absorption for specific spectral band applications. The 17 micron pixel pitch FPAs are currently being considered for the next generation soldier systems such as thermal weapon sights (TWS), vehicle driver vision enhancers (DVE), digitally fused enhanced night vision goggles (DENVG) and unmanned air vehicle (UAV) surveillance sensors, because of overall thermal imaging system size, weight and power advantages.

  11. Children's Identification of Questions from Rising Terminal Pitch

    ERIC Educational Resources Information Center

    Saindon, Mathieu R.; Trehub, Sandra E.; Schellenberg, E. Glenn; van Lieshout, Pascal

    2016-01-01

    Young children are slow to master conventional intonation patterns in their "yes/no" questions, which may stem from imperfect understanding of the links between terminal pitch contours and pragmatic intentions. In Experiment 1, five to ten-year-old children and adults were required to judge utterances as questions or statements on the…

  12. On the acoustic radiation of a pitching airfoil

    NASA Astrophysics Data System (ADS)

    Manela, A.

    2013-07-01

    We examine the acoustic far field of a thin elastic airfoil, immersed in low-Mach non-uniform stream flow, and actuated by small-amplitude sinusoidal pitching motion. The near-field fluid-structure interaction problem is analyzed using potential thin-airfoil theory, combined with a discrete vortex model to describe the evolution of airfoil trailing edge wake. The leading order dipole-sound signature of the system is investigated using Powell-Howe acoustic analogy. Compared with a pitching rigid airfoil, the results demonstrate a two-fold effect of structure elasticity on airfoil acoustic field: at actuation frequencies close to the system least stable eigenfrequency, elasticity amplifies airfoil motion amplitude and associated sound levels; however, at frequencies distant from this eigenfrequency, structure elasticity acts to absorb system kinetic energy and reduce acoustic radiation. In the latter case, and with increasing pitching frequency ωp, a rigid-airfoil setup becomes significantly noisier than an elastic airfoil, owing to an ω _p^{5/2} increase of its direct motion noise component. Unlike rigid airfoil signature, it is shown that wake sound contribution to elastic airfoil radiation is significant for all ωp. Remarkably, this contribution contains, in addition to the fundamental pitching frequency, its odd multiple harmonics, which result from nonlinear interactions between the airfoil and the wake. The results suggest that structure elasticity may serve as a viable means for design of flapping flight noise control methodologies.

  13. Pitch and Loudness Tinnitus in Individuals with Presbycusis

    PubMed Central

    Seimetz, Bruna Macangnin; Teixeira, Adriane Ribeiro; Rosito, Leticia Petersen Schmidt; Flores, Leticia Sousa; Pappen, Carlos Henrique; Dall'igna, Celso

    2016-01-01

    Introduction Tinnitus is a symptom that is often associated with presbycusis. Objective This study aims to analyze the existence of association among hearing thresholds, pitch, and loudness of tinnitus in individuals with presbycusis, considering the gender variable. Methods Cross-sectional, descriptive, and prospective study, whose sample consisted of individuals with tinnitus and diagnosis of presbycusis. For the evaluation, we performed anamnesis along with otoscopy, pure tone audiometry, and acuphenometry to analyze the psychoacoustic characteristics of tinnitus individuals. Results The sample consisted of 49 subjects, with a mean age of 69.57 ± 6.53 years, who presented unilateral and bilateral tinnitus, therefore, a sample of 80 ears. In analyzing the results, as for acuphenometry, the loudness of tinnitus was more present at 0dB and the pitch was 6HKz and 8HKz. Regarding the analysis of the association between the frequency of greater hearing threshold and tinnitus pitch, no statistical significance (p = 0.862) was found. As for the association between the intensity of greater hearing threshold and tinnitus loudness, no statistical significance (p = 0.115) was found. Conclusion There is no significant association between the hearing loss of patients with presbycusis and the pitch and loudness of tinnitus. PMID:27746834

  14. Aerodynamic Control of a Pitching Airfoil by Distributed Bleed Actuation

    NASA Astrophysics Data System (ADS)

    Kearney, John; Glezer, Ari

    2013-11-01

    The aerodynamic forces and moments on a dynamically pitching 2-D airfoil model are controlled in wind tunnel experiments using distributed active bleed. Bleed flow on the suction surface downstream of the leading edge is driven by pressure differences across the airfoil and is regulated by low-power louver actuators. The bleed interacts with cross flows to effect time-dependent variations of the vorticity flux and thereby alters the local flow attachment, resulting in significant changes in pre- and post-stall lift and pitching moment (over 50% increase in baseline post-stall lift). The flow field over the airfoil is measured using high-speed (2000 fps) PIV, resolving the dynamics and characteristic time-scales of production and advection of vorticity concentrations that are associated with transient variations in the aerodynamic forces and moments. In particular, it is shown that the actuation improves the lift hysteresis and pitch stability during the oscillatory pitching by altering the evolution of the dynamic stall vortex and the ensuing flow attachment during the downstroke. Supported by the Rotorcraft Center (VLRCOE) at Georgia Tech.

  15. Pitch jnd and the tritone paradox: The linguistic nexus

    NASA Astrophysics Data System (ADS)

    Safari, Kourosh

    2002-11-01

    Previous research has shown a connection between absolute pitch (the ability to name a specific pitch in the absence of any reference) and native competence in a tone language (Deutsch, 1990). In tone languages, tone is one of the features which determines the lexical meaning of a word. This study investigates the relationship between native competence in a tone language and the just noticeable difference of pitch. Furthermore, the tritone paradox studies have shown that subjects hear two tritones (with bell-shaped spectral envelopes) as either ascending or descending depending on their linguistic backgrounds (Deutsch, 1987). It is hypothesized that the native speakers of tone languages have a higher JND for pitch, and hear the two tones of the tritone paradox as ascending, whereas, native speakers of nontone languages hear them as descending. This study will indicate the importance of early musical training for the development of acute tone sensitivity. It will also underline the importance of language and culture in the way it shapes our musical understanding. The significance of this study will be in the areas of music education and pedagogy.

  16. Grating pitch measurements with the molecular measuring machine

    NASA Astrophysics Data System (ADS)

    Kramar, John; Jun, Jau-Shi J.; Penzes, William B.; Scire, Fredric; Teague, E. Clayton; Villarrubia, John S.

    1999-11-01

    At the National Institute of Standards and Technology, we are building a metrology instrument called the Molecular Measuring Machine (M3) with the goal of performing nanometer- accuracy two-dimensional feature placement measurements over a 50 mm by 50 mm area. The instrument uses a scanning tunneling microscope to probe the surface and an interferometer system to measure the lateral probe movement, both having sub-nanometer resolution. The continuous vertical measurement range is 5 micrometer, and up to 2 mm can be covered by stitching overlapping ranges. The instrument includes temperature control with millikelvin stability, an ultra-high vacuum environment with a base pressure below 10-5 Pa, and seismic and acoustic vibration isolation. Pitch measurements were performed on gratings made by holographic exposure of photoresist and on gratings made by laser-focused atomic deposition of Cr. The line pitch for these gratings ranged from 200 nm to 400 nm with an estimated standard uncertainty of the average pitch of 25 X 10-6. This fractional uncertainty is derived from an analysis of the sources of uncertainty for a 1 mm point-to- point measurement, including the effects of alignment, Abbe offset, motion cross-coupling, and temperature variations. These grating pitch measurements are uniquely accomplished on M3 because of the combination of probe resolution and long-range interferometer-controlled stage. This instrument could uniquely address certain dimensional metrology needs in the data storage industry.

  17. Native and Nonnative Processing of Japanese Pitch Accent

    ERIC Educational Resources Information Center

    Wu, Xianghua; Tu, Jung-Yueh; Wang, Yue

    2012-01-01

    The theoretical framework of this study is based on the prevalent debate of whether prosodic processing is influenced by higher level linguistic-specific circuits or reflects lower level encoding of physical properties. Using the dichotic listening technique, the study investigates the hemispheric processing of Japanese pitch accent by native…

  18. Singing Video Games May Help Improve Pitch-Matching Accuracy

    ERIC Educational Resources Information Center

    Paney, Andrew S.

    2015-01-01

    The purpose of this study was to investigate the effect of singing video games on the pitch-matching skills of undergraduate students. Popular games like "Rock Band" and "Karaoke Revolutions" rate players' singing based on the correctness of the frequency of their sung response. Players are motivated to improve their…

  19. Distraction by Novel and Pitch-Deviant Sounds in Children

    PubMed Central

    Wetzel, Nicole; Schröger, Erich; Widmann, Andreas

    2016-01-01

    The control of attention is an important part of our executive functions and enables us to focus on relevant information and to ignore irrelevant information. The ability to shield against distraction by task-irrelevant sounds is suggested to mature during school age. The present study investigated the developmental time course of distraction in three groups of children aged 7–10 years. Two different types of distractor sounds that have been frequently used in auditory attention research—novel environmental and pitch-deviant sounds—were presented within an oddball paradigm while children performed a visual categorization task. Reaction time measurements revealed decreasing distractor-related impairment with age. Novel environmental sounds impaired performance in the categorization task more than pitch-deviant sounds. The youngest children showed a pronounced decline of novel-related distraction effects throughout the experimental session. Such a significant decline as a result of practice was not observed in the pitch-deviant condition and not in older children. We observed no correlation between cross-modal distraction effects and performance in standardized tests of concentration and visual distraction. Results of the cross-modal distraction paradigm indicate that separate mechanisms underlying the processing of novel environmental and pitch-deviant sounds develop with different time courses and that these mechanisms develop considerably within a few years in middle childhood. PMID:28018281

  20. On the rotation and pitching of flat plates

    NASA Astrophysics Data System (ADS)

    Jin, Yaqing; Ji, Sheng; Chamorro, Leonardo P.

    2016-11-01

    Wind tunnel experiments were performed to characterize the flow-induced rotation and pitching of various flat plates as a function of the thickness ratio, the location of the axis of rotation and turbulence levels. High-resolution telemetry, laser tachometer, and hotwire were used to get time series of the plates motions and the signature of the wake flow at a specific location. Results show that a minor axis offset can induce high-order modes in the plate rotation under low turbulence due to torque unbalance. The spectral decomposition of the flow velocity in the plate wake reveals the existence of a dominating high-frequency mode that corresponds to a static-like vortex shedding occurring at the maximum plate pitch, where the characteristic length scale is the projected width at maximum pitch. The plate thickness ratio shows inverse relation with the angular velocity. A simple model is derived to explain the linear relation between pitching frequency and wind speed. The spectra of the plate rotation show nonlinear relation with the incoming turbulence, and the dominating role of the generated vortices in the plate motions.

  1. Processing pitch in a nonhuman mammal (Chinchilla laniger).

    PubMed

    Shofner, William P; Chaney, Megan

    2013-05-01

    Whether the mechanisms giving rise to pitch reflect spectral or temporal processing has long been debated. Generally, sounds having strong harmonic structures in their spectra have strong periodicities in their temporal structures. We found that when a wideband harmonic tone complex is passed through a noise vocoder, the resulting sound can have a harmonic structure with a large peak-to-valley ratio, but with little or no periodicity in the temporal structure. To test the role of harmonic structure in pitch perception for a nonhuman mammal, we measured behavioral responses to noise-vocoded tone complexes in chinchillas (Chinchilla laniger) using a stimulus generalization paradigm. Chinchillas discriminated either a harmonic tone complex or an iterated rippled noise from a 1-channel vocoded version of the tone complex. When tested with vocoded versions generated with 8, 16, 32, 64, and 128 channels, responses were similar to those of the 1-channel version. Behavioral responses could not be accounted for based on harmonic peak-to-valley ratio as the acoustic cue, but could be accounted for based on temporal properties of the autocorrelation functions such as periodicity strength or the height of the first peak. The results suggest that pitch perception does not arise through spectral processing in nonhuman mammals but rather through temporal processing. The conclusion that spectral processing contributes little to pitch in nonhuman mammals may reflect broader cochlear tuning than that described in humans.

  2. 14 CFR 25.33 - Propeller speed and pitch limits.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Section 25.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight General § 25.33 Propeller speed and pitch limits...) The airplane stationary under standard atmospheric conditions with no wind; and (3) The...

  3. 14 CFR 25.33 - Propeller speed and pitch limits.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Section 25.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight General § 25.33 Propeller speed and pitch limits...) The airplane stationary under standard atmospheric conditions with no wind; and (3) The...

  4. 14 CFR 25.33 - Propeller speed and pitch limits.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Section 25.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight General § 25.33 Propeller speed and pitch limits...) The airplane stationary under standard atmospheric conditions with no wind; and (3) The...

  5. 14 CFR 25.33 - Propeller speed and pitch limits.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Section 25.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight General § 25.33 Propeller speed and pitch limits...) The airplane stationary under standard atmospheric conditions with no wind; and (3) The...

  6. 14 CFR 25.33 - Propeller speed and pitch limits.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Section 25.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight General § 25.33 Propeller speed and pitch limits...) The airplane stationary under standard atmospheric conditions with no wind; and (3) The...

  7. Clarifying the Empirical Connection of New Entrants' E-Learning Systems Use to Their Job Adaptation and Their Use Patterns under the Collective-Individual Training Environment

    ERIC Educational Resources Information Center

    Chen, Hsiu-Ju

    2012-01-01

    In recent years, with the development of e-learning, it is feasible for enterprises to adopt information systems to enhance organizations' human capital and knowledge renewal for competition. e-Learning systems designed for new entrants training aim to facilitate new entrants' job adaptation; however, the empirical link between their system use…

  8. Blade-Pitch Control for Quieting Tilt-Rotor Aircraft

    NASA Technical Reports Server (NTRS)

    Betzina, Mark D.; Nguyen, Khanh Q.

    2004-01-01

    A method of reducing the noise generated by a tilt-rotor aircraft during descent involves active control of the blade pitch of the rotors. This method is related to prior such noise-reduction methods, of a type denoted generally as higher-harmonic control (HHC), in which the blade pitch is made to oscillate at a harmonic of the frequency of rotation of the rotor. A tilt-rotor aircraft is so named because mounted at its wing tips are motors that can be pivoted to enable the aircraft to take off and land like a helicopter or to fly like a propeller airplane. When the aircraft is operating in its helicopter mode, the rotors generate more thrust per unit rotor-disk area than helicopter rotors do, thus producing more blade-vortex interaction (BVI) noise. BVI is a major source of noise produced by helicopters and tilt-rotor aircraft during descent: When a rotor descends into its own wake, the interaction of each blade with the blade-tip vortices generated previously gives rise to large air-pressure fluctuations. These pressure fluctuations radiate as distinct, impulsive noise. In general, the pitch angle of the rotor blades of a tilt-rotor aircraft is controlled by use of a swash plate connected to the rotor blades by pitch links. In both prior HHC methods and the present method, HHC control signals are fed as input to swash-plate control actuators, causing the rotor-blade pitch to oscillate. The amplitude, frequency, and phase of the control signal can be chosen to minimize BVI noise.

  9. Biomimetic propulsion under random heaving conditions, using active pitch control

    NASA Astrophysics Data System (ADS)

    Politis, Gerasimos; Politis, Konstantinos

    2014-05-01

    Marine mammals travel long distances by utilizing and transforming wave energy to thrust through proper control of their caudal fin. On the other hand, manmade ships traveling in a wavy sea store large amounts of wave energy in the form of kinetic energy for heaving, pitching, rolling and other ship motions. A natural way to extract this energy and transform it to useful propulsive thrust is by using a biomimetic wing. The aim of this paper is to show how an actively pitched biomimetic wing could achieve this goal when it performs a random heaving motion. More specifically, we consider a biomimetic wing traveling with a given translational velocity in an infinitely extended fluid and performing a random heaving motion with a given energy spectrum which corresponds to a given sea state. A formula is invented by which the instantaneous pitch angle of the wing is determined using the heaving data of the current and past time steps. Simulations are then performed for a biomimetic wing at different heave energy spectra, using an indirect Source-Doublet 3-D-BEM, together with a time stepping algorithm capable to track the random motion of the wing. A nonlinear pressure type Kutta condition is applied at the trailing edge of the wing. With a mollifier-based filtering technique, the 3-D unsteady rollup pattern created by the random motion of the wing is calculated without any simplifying assumptions regarding its geometry. Calculated unsteady forces, moments and useful power, show that the proposed active pitch control always results in thrust producing motions, with significant propulsive power production and considerable beneficial stabilizing action to ship motions. Calculation of the power required to set the pitch angle prove it to be a very small percentage of the useful power and thus making the practical application of the device very tractable.

  10. QUALIFICATION TEST OF THE PITCH REACTION WHEEL ELECTRONICS, LMSD P/N 1315322,

    DTIC Science & Technology

    The Pitch Reaction Wheel Electronics is a sealed unit used in the satellite attitude control system. This report describes the test conducted for...qualification of the pitch reaction wheel in various controlled electrical and physical environments.

  11. Do musicians with perfect pitch have more autism traits than musicians without perfect pitch? An empirical study.

    PubMed

    Dohn, Anders; Garza-Villarreal, Eduardo A; Heaton, Pamela; Vuust, Peter

    2012-01-01

    Perfect pitch, also known as absolute pitch (AP), refers to the rare ability to identify or produce a musical tone correctly without the benefit of an external reference. AP is often considered to reflect musical giftedness, but it has also been associated with certain disabilities due to increased prevalence of AP in individuals with sensory and developmental disorders. Here, we determine whether individual autistic traits are present in people with AP. We quantified subclinical levels of autism traits using the Autism-Spectrum Quotient (AQ) in three matched groups of subjects: 16 musicians with AP (APs), 18 musicians without AP (non-APs), and 16 non-musicians. In addition, we measured AP ability by a pitch identification test with sine wave tones and piano tones. We found a significantly higher degree of autism traits in APs than in non-APs and non-musicians, and autism scores were significantly correlated with pitch identification scores (r = .46, p = .003). However, our results showed that APs did not differ from non-APs on diagnostically crucial social and communicative domain scores and their total AQ scores were well below clinical thresholds for autism. Group differences emerged on the imagination and attention switching subscales of the AQ. Thus, whilst these findings do link AP with autism, they also show that AP ability is most strongly associated with personality traits that vary widely within the normal population.

  12. Variability of a "force signature" during windmill softball pitching and relationship between discrete force variables and pitch velocity.

    PubMed

    Nimphius, Sophia; McGuigan, Michael R; Suchomel, Timothy J; Newton, Robert U

    2016-06-01

    This study assessed reliability of discrete ground reaction force (GRF) variables over multiple pitching trials, investigated the relationships between discrete GRF variables and pitch velocity (PV) and assessed the variability of the "force signature" or continuous force-time curve during the pitching motion of windmill softball pitchers. Intraclass correlation coefficient (ICC) for all discrete variables was high (0.86-0.99) while the coefficient of variance (CV) was low (1.4-5.2%). Two discrete variables were significantly correlated to PV; second vertical peak force (r(5)=0.81, p=0.03) and time between peak forces (r(5)=-0.79; p=0.03). High ICCs and low CVs support the reliability of discrete GRF and PV variables over multiple trials and significant correlations indicate there is a relationship between the ability to produce force and the timing of this force production with PV. The mean of all pitchers' curve-average standard deviation of their continuous force-time curves demonstrated low variability (CV=4.4%) indicating a repeatable and identifiable "force signature" pattern during this motion. As such, the continuous force-time curve in addition to discrete GRF variables should be examined in future research as a potential method to monitor or explain changes in pitching performance.

  13. Two Studies of Pitch in String Instrument Vibrato: Perception and Pitch Matching Responses of University and High School String Players

    ERIC Educational Resources Information Center

    Geringer, John M.; MacLeod, Rebecca B.; Ellis, Julia C.

    2014-01-01

    We investigated pitch perception of string vibrato tones among string players in two separate studies. In both studies we used tones of acoustic instruments (violin and cello) as stimuli. In the first, we asked 192 high school and university string players to listen to a series of tonal pairs: one tone of each pair was performed with vibrato and…

  14. The sound of size: crossmodal binding in pitch-size synesthesia: a combined TMS, EEG and psychophysics study.

    PubMed

    Bien, Nina; ten Oever, Sanne; Goebel, Rainer; Sack, Alexander T

    2012-01-02

    Crossmodal binding usually relies on bottom-up stimulus characteristics such as spatial and temporal correspondence. However, in case of ambiguity the brain has to decide whether to combine or segregate sensory inputs. We hypothesise that widespread, subtle forms of synesthesia provide crossmodal mapping patterns which underlie and influence multisensory perception. Our aim was to investigate if such a mechanism plays a role in the case of pitch-size stimulus combinations. Using a combination of psychophysics and ERPs, we could show that despite violations of spatial correspondence, the brain specifically integrates certain stimulus combinations which are congruent with respect to our hypothesis of pitch-size synesthesia, thereby impairing performance on an auditory spatial localisation task (Ventriloquist effect). Subsequently, we perturbed this process by functionally disrupting a brain area known for its role in multisensory processes, the right intraparietal sulcus, and observed how the Ventriloquist effect was abolished, thereby increasing behavioural performance. Correlating behavioural, TMS and ERP results, we could retrace the origin of the synesthestic pitch-size mappings to a right intraparietal involvement around 250 ms. The results of this combined psychophysics, TMS and ERP study provide evidence for shifting the current viewpoint on synesthesia more towards synesthesia being at the extremity of a spectrum of normal, adaptive perceptual processes, entailing close interplay between the different sensory systems. Our results support this spectrum view of synesthesia by demonstrating that its neural basis crucially depends on normal multisensory processes.

  15. Unsteady Performance of Finite-Span Pitching Propulsors in Mixtures of Side-by-Side and In-Line Arrangements

    NASA Astrophysics Data System (ADS)

    Kurt, Melike; Moored, Keith

    2016-11-01

    Birds, insects, and fish propel themselves by flapping their wings or oscillating their fins in unsteady motions. Many of these animals fly or swim in groups or collectives, typically described as flocks, swarms and schools. The three-dimensional steady flow interactions and the two dimensional unsteady flow interactions that occur in collectives are well characterized. However, the interactions that occur among three-dimensional unsteady propulsors remain relatively unexplored. The aim of the current study is to measure the forces acting on and the energetics of two finite-span pitching wings. The wings are arranged in mixtures of canonical in-line and side-by-side configurations while the phase delay between the pitching wings is varied. The thrust force, fluid-mediated interaction force between the wings and the propulsive efficiency are quantified. The three-dimensional interaction mechanisms are compared and contrasted with previously examined two-dimensional mechanisms. Stereoscopic particle image velocimetry is employed to characterize the three-dimensional flow structures along the span of the pitching wings.

  16. RBF neural network based PI pitch controller for a class of 5-MW wind turbines using particle swarm optimization algorithm.

    PubMed

    Poultangari, Iman; Shahnazi, Reza; Sheikhan, Mansour

    2012-09-01

    In order to control the pitch angle of blades in wind turbines, commonly the proportional and integral (PI) controller due to its simplicity and industrial usability is employed. The neural networks and evolutionary algorithms are tools that provide a suitable ground to determine the optimal PI gains. In this paper, a radial basis function (RBF) neural network based PI controller is proposed for collective pitch control (CPC) of a 5-MW wind turbine. In order to provide an optimal dataset to train the RBF neural network, particle swarm optimization (PSO) evolutionary algorithm is used. The proposed method does not need the complexities, nonlinearities and uncertainties of the system under control. The simulation results show that the proposed controller has satisfactory performance.

  17. Pitch and Time, Tonality and Meter: How Do Musical Dimensions Combine?

    ERIC Educational Resources Information Center

    Prince, Jon B.; Thompson, William F.; Schmuckler, Mark A.

    2009-01-01

    The authors examined how the structural attributes of tonality and meter influence musical pitch-time relations. Listeners heard a musical context followed by probe events that varied in pitch class and temporal position. Tonal and metric hierarchies contributed additively to the goodness-of-fit of probes, with pitch class exerting a stronger…

  18. The Effect of Vocal Modeling on Pitch-Matching Accuracy of Elementary Schoolchildren.

    ERIC Educational Resources Information Center

    Green, Georgia A.

    1990-01-01

    Examines effects of adult male, adult female, and child vocal modeling on the pitch-matching accuracy of 282 elementary school students. Reveals students best matched the child model's pitch followed by female, then male models. Considers relationship of type of model to flatness or sharpness in pitch. (CH)

  19. Pitch Discrimination and Melodic Memory in Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Stanutz, Sandy; Wapnick, Joel; Burack, Jacob A.

    2014-01-01

    Background: Pitch perception is enhanced among persons with autism. We extended this finding to memory for pitch and melody among school-aged children. Objective: The purpose of this study was to investigate pitch memory in musically untrained children with autism spectrum disorders, aged 7-13 years, and to compare it to that of age- and…

  20. Thermal Characteristics of Pitch Based Carbon Foam and Phase Change Materials

    DTIC Science & Technology

    2005-03-01

    communications systems. Carbon foam derived from a blown mesophase pitch precursor can be considered to be an interconnected network of graphitic...THERMAL CHARACTERISTICS OF PITCH BASED CARBON FOAM AND PHASE CHANGE MATERIALS THESIS Kevin...APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. THERMAL CHARACTERISTICS OF PITCH BASED CARBON FOAM AND PHASE CHANGE MATERIALS

  1. Large-Eddy Simulation Analysis of Unsteady Separation Over a Pitching Airfoil at High Reynolds Number

    DTIC Science & Technology

    2013-12-24

    helicopter rotor blades, wind turbine blades, pitching and flapping airfoils and wings , and rotating turbomachinery blades. For instance, helicopter...of turbulent flow over a pitching airfoil at realistic Reynolds and Mach numbers is performed. Numerical stability at high Reynolds number...Approved for Public Release; Distribution Unlimited Large-Eddy Simulation Analysis of Unsteady Separation Over a Pitching Airfoil at High Reynolds

  2. Therapy to Improve Pitch in Young Adults with Profound Hearing Loss.

    ERIC Educational Resources Information Center

    Subtelny, Joanne; And Others

    1989-01-01

    A voice training program to improve pitch register was developed for profoundly hearing-impaired young adults. Ten students of the National Technical Institute for the Deaf completed the program; results showed a significant reduction in pitch level, as well as improvement in pitch control and word intelligibility. (Author/JDD)

  3. Processes of recovering fatty acids and sterols from tall oil pitch

    SciTech Connect

    Hughes, R. E.

    1985-06-18

    An improved process of enhancing the recovery of fatty acids from tall oil pitch is disclosed. The process includes a hydrolysis step for increasing the free fatty acid available for recovery from tall oil pitch during the distillation process. The hydrolysis step also enables the recovery of sterols where the tall oil pitch is of the type which is rich in sterol esters.

  4. EEMD based pitch evaluation method for accurate grating measurement by AFM

    NASA Astrophysics Data System (ADS)

    Li, Changsheng; Yang, Shuming; Wang, Chenying; Jiang, Zhuangde

    2016-09-01

    The pitch measurement and AFM calibration precision are significantly influenced by the grating pitch evaluation method. This paper presents the ensemble empirical mode decomposition (EEMD) based pitch evaluation method to relieve the accuracy deterioration caused by high and low frequency components of scanning profile during pitch evaluation. The simulation analysis shows that the application of EEMD can improve the pitch accuracy of the FFT-FT algorithm. The pitch error is small when the iteration number of the FFT-FT algorithms was 8. The AFM measurement of the 500 nm-pitch one-dimensional grating shows that the EEMD based pitch evaluation method could improve the pitch precision, especially the grating line position precision, and greatly expand the applicability of the gravity center algorithm when particles and impression marks were distributed on the sample surface. The measurement indicates that the nonlinearity was stable, and the nonlinearity of x axis and forward scanning was much smaller than their counterpart. Finally, a detailed pitch measurement uncertainty evaluation model suitable for commercial AFMs was demonstrated and a pitch uncertainty in the sub-nanometer range was achieved. The pitch uncertainty was reduced about 10% by EEMD.

  5. Stimulus-Dependent Flexibility in Non-Human Auditory Pitch Processing

    ERIC Educational Resources Information Center

    Bregman, Micah R.; Patel, Aniruddh D.; Gentner, Timothy Q.

    2012-01-01

    Songbirds and humans share many parallels in vocal learning and auditory sequence processing. However, the two groups differ notably in their abilities to recognize acoustic sequences shifted in absolute pitch (pitch height). Whereas humans maintain accurate recognition of words or melodies over large pitch height changes, songbirds are…

  6. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 6 2013-07-01 2013-07-01 false Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from...

  7. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 6 2011-07-01 2011-07-01 false Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from...

  8. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 6 2014-07-01 2013-07-01 true Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from...

  9. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 6 2010-07-01 2010-07-01 false Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from...

  10. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 6 2012-07-01 2012-07-01 false Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from...

  11. Adaptive Controller Effects on Pilot Behavior

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Gregory, Irene M.; Hempley, Lucas E.

    2014-01-01

    Adaptive control provides robustness and resilience for highly uncertain, and potentially unpredictable, flight dynamics characteristic. Some of the recent flight experiences of pilot-in-the-loop with an adaptive controller have exhibited unpredicted interactions. In retrospect, this is not surprising once it is realized that there are now two adaptive controllers interacting, the software adaptive control system and the pilot. An experiment was conducted to categorize these interactions on the pilot with an adaptive controller during control surface failures. One of the objectives of this experiment was to determine how the adaptation time of the controller affects pilots. The pitch and roll errors, and stick input increased for increasing adaptation time and during the segment when the adaptive controller was adapting. Not surprisingly, altitude, cross track and angle deviations, and vertical velocity also increase during the failure and then slowly return to pre-failure levels. Subjects may change their behavior even as an adaptive controller is adapting with additional stick inputs. Therefore, the adaptive controller should adapt as fast as possible to minimize flight track errors. This will minimize undesirable interactions between the pilot and the adaptive controller and maintain maneuvering precision.

  12. Dual pitch plasmonic devices for polarization enhanced colour based sensing

    NASA Astrophysics Data System (ADS)

    Langley, D.; Balaur, E.; Sadatnajafi, C.; Abbey, B.

    2016-12-01

    Plasmonic devices provide a unique sensitivity to changes in the permittivity of the immediate, near-surface environment. In this work we explore the use of dual pitch plasmonic devices combined with microfluidics for polarization enhanced colour sensing of a chemicals' refractive index. We demonstrate that the use of cross-shaped apertures can produce polarization tunable color based sensing in the optical regime and show that the spectral variations as a function of the incident polarization can be decomposed into contributions from the two orthogonal modes that characterize the dual pitch plasmonic device. Finally we demonstrate that the use of the full colour spectrum in the visible range in combination with polarization control enables sensing `by-eye' of refractive index changes below 1 × 10-3 RIU.

  13. Neurological and developmental approaches to poor pitch perception and production.

    PubMed

    Loui, Psyche; Demorest, Steven M; Pfordresher, Peter Q; Iyer, Janani

    2015-03-01

    Whereas much of research in music and neuroscience is aimed at understanding the mechanisms by which the human brain facilitates music, emerging interest in the neuromusic community aims to translate basic music research into clinical and educational applications. In the present paper, we explore the problems of poor pitch perception and production from both neurological and developmental/educational perspectives. We begin by reviewing previous and novel findings on the neural regulation of pitch perception and production. We then discuss issues in measuring singing accuracy consistently between the laboratory and educational settings. We review the Seattle Singing Accuracy Protocol--a new assessment tool that we hope can be adopted by cognitive psychologists as well as music educators-and we conclude with some suggestions that the present interdisciplinary approach might offer for future research.

  14. Plasma pitch angle distributions near the substorm injection front

    NASA Technical Reports Server (NTRS)

    Moore, T. E.; Arnoldy, R. L.

    1982-01-01

    ATS-6 spacecraft hot plasma instrument data obtained during January, 1980 is presented, which provides electron and ion pitch distributions in the vicinity of an earthward-propagating, substorm-associated abrupt plasma change near synchronous orbit. Evidence is found of symmetric atmospheric source cones for few 100-eV electrons after front passage, supporting both (1) concept of atmospheric electron degradation of the hot, high-altitude plasma, and (2) the proposal that the injection front is a moving, precipitation-flow boundary between the hot plasma and the cooler plasma that has become spectrally degraded via interaction with the atmosphere. The enhanced hot plasma electron intensities appearing in association with front passage exhibit a modest, field-aligned anisotropy with minima at pitch angles characteristic of symmetric loss cones, consistent with mirror compression of the electrons on inward-collapsing field lines.

  15. Active and passive stabilization of body pitch in insect flight

    PubMed Central

    Ristroph, Leif; Ristroph, Gunnar; Morozova, Svetlana; Bergou, Attila J.; Chang, Song; Guckenheimer, John; Wang, Z. Jane; Cohen, Itai

    2013-01-01

    Flying insects have evolved sophisticated sensory–motor systems, and here we argue that such systems are used to keep upright against intrinsic flight instabilities. We describe a theory that predicts the instability growth rate in body pitch from flapping-wing aerodynamics and reveals two ways of achieving balanced flight: active control with sufficiently rapid reactions and passive stabilization with high body drag. By glueing magnets to fruit flies and perturbing their flight using magnetic impulses, we show that these insects employ active control that is indeed fast relative to the instability. Moreover, we find that fruit flies with their control sensors disabled can keep upright if high-drag fibres are also attached to their bodies, an observation consistent with our prediction for the passive stability condition. Finally, we extend this framework to unify the control strategies used by hovering animals and also furnish criteria for achieving pitch stability in flapping-wing robots. PMID:23697713

  16. Optimization of array element pitch for NDE applications

    NASA Astrophysics Data System (ADS)

    Wilcox, Paul D.

    2015-03-01

    This paper quantitatively investigates how the pitch of elements in periodic ultrasonic arrays is related to the level of grating lobe artefacts in images. A theoretical framework is developed that enables the Point Spread Function of periodic arrays to be expressed as the sum of contributions from a main lobe and possible grating lobes. This analysis yields the classical array element pitch rules in the far-field, single-frequency case. However, numerical simulations show that the rules can be considerably relaxed in the near-field, broadband case without significantly compromising image quality. Results from artificially spatially-downsampled experimental data are presented to support this conclusion. Finally, extensions to other common inspection configurations are suggested.

  17. Neurological and developmental approaches to poor pitch perception and production

    PubMed Central

    Loui, Psyche; Demorest, Steven M.; Pfordresher, Peter Q.; Iyer, Janani

    2014-01-01

    Whereas much of research in music and neuroscience is aimed at understanding the mechanisms by which the human brain facilitates music, emerging interest in the neuromusic community aims to translate basic music research into clinical and educational applications. In the present workshop, we explore the problems of poor pitch perception and production from both neurological and developmental/educational perspectives. We begin by reviewing previous and novel findings on the neural regulation of pitch perception and production. We then discuss issues in measuring singing accuracy consistently between the laboratory and educational settings. We review the Seattle Singing Accuracy Protocol—a new assessment tool that we hope can be adopted by cognitive psychologists as well as music educators—and we conclude with some suggestions that the present interdisciplinary approach might offer for future research. PMID:25773643

  18. Self-consistent pitch angle diffusion of newborn ions

    NASA Astrophysics Data System (ADS)

    Yoon, P. H.; Ziebell, L. F.; Wu, C. S.

    1991-04-01

    A self-consistent analysis of pitch angle diffusion of newborn ions by low-frequency hydromagnetic waves predominantly propagating in one direction has been carried out. It is found that in the wave frame defined in velocity space the time evolution of an ion distribution can be described as undergoing purely pitch angle diffusion. The role of the resonant versus nonresonant diffusion is discussed in detail, and it is shown that a time-asymptotic distribution of a particular form develops. It is analytically and numerically shown that the self-consistent diffusion process leads to a time-asymptotic partial shell distributions. The relevance of this finding to observations that the ion distributions in the far upstream of cometary bow shocks have a partial shell structure rather than a complete shell is pointed out.

  19. New SOFRADIR 10μm pixel pitch infrared products

    NASA Astrophysics Data System (ADS)

    Lefoul, X.; Pere-Laperne, N.; Augey, T.; Rubaldo, L.; Aufranc, Sébastien; Decaens, G.; Ricard, N.; Mazaleyrat, E.; Billon-Lanfrey, D.; Gravrand, Olivier; Bisotto, Sylvette

    2014-10-01

    Recent advances in miniaturization of IR imaging technology have led to a growing market for mini thermal-imaging sensors. In that respect, Sofradir development on smaller pixel pitch has made much more compact products available to the users. When this competitive advantage is mixed with smaller coolers, made possible by HOT technology, we achieved valuable reductions in the size, weight and power of the overall package. At the same time, we are moving towards a global offer based on digital interfaces that provides our customers simplifications at the IR system design process while freeing up more space. This paper discusses recent developments on hot and small pixel pitch technologies as well as efforts made on compact packaging solution developed by SOFRADIR in collaboration with CEA-LETI.

  20. Pitch-based pattern splitting for 1D layout

    NASA Astrophysics Data System (ADS)

    Nakayama, Ryo; Ishii, Hiroyuki; Mikami, Koji; Tsujita, Koichiro; Yaegashi, Hidetami; Oyama, Kenichi; Smayling, Michael C.; Axelrad, Valery

    2015-07-01

    The pattern splitting algorithm for 1D Gridded-Design-Rules layout (1D layout) for sub-10 nm node logic devices is shown. It is performed with integer linear programming (ILP) based on the conflict graph created from a grid map for each designated pitch. The relation between the number of times for patterning and the minimum pitch is shown systematically with a sample pattern of contact layer for each node. From the result, the number of times for patterning for 1D layout is fewer than that for conventional 2D layout. Moreover, an experimental result including SMO and total integrated process with hole repair technique is presented with the sample pattern of contact layer whose pattern density is relatively high among critical layers (fin, gate, local interconnect, contact, and metal).

  1. An airfoil pitch apparatus-modeling and control design

    NASA Astrophysics Data System (ADS)

    Andrews, Daniel R.

    1989-03-01

    The study of dynamic stall of rapidly pitching airfoils is being conducted at NASA Ames Research Center. Understanding this physical phenomenon will aid in improving the maneuverability of fighter aircraft as well as civilian aircraft. A wind tunnel device which can linearly pitch and control an airfoil with rapid dynamic response is needed for such tests. To develop a mechanism capable of high accelerations, an accurate model and control system is created. The model contains mathematical representations of the mechanical system, including mass, spring, and damping characteristics for each structural element, as well as coulomb friction and servovalve saturation. Electrical components, both digital and analog, linear and nonlinear, are simulated. The implementation of such a high-performance system requires detailed control design as well as state-of-the-art components. This paper describes the system model, states the system requirements, and presents results of its theoretical performance which maximizes the structural and hydraulic aspects of this system.

  2. An electromyographic analysis of the upper extremity in pitching.

    PubMed

    Digiovine, N M; Jobe, F W; Pink, M; Perry, J

    1992-01-01

    The upper extremity is vulnerable to injury during the baseball pitch because of the repetitious nature of the action, the extremes in range of motion, and the high angular velocities and torques generated at the shoulder and elbow. Hence this study was designed to describe the muscle-firing patterns through fine-wire electromyography in 29 muscle bellies in the upper extremities of skilled pitchers during the fastball pitch. The results demonstrated that the muscles functioned with precise timing for joint stabilization to prevent injury, joint activation to transfer forces to the ball, and joint deceleration to dissipate forces after ball release. The synchrony of reciprocal and sequential muscle contraction necessary to accomplish these functions was clearly evident. This study provides a better understanding of the coordinated sequence of muscle activity during the throwing motion; this understanding is crucial to the development of exercise protocols and surgical procedures used for treatment and prevention of shoulder and elbow injuries in the throwing athlete.

  3. Neural Mechanisms Underlying Musical Pitch Perception and Clinical Applications Including Developmental Dyslexia.

    PubMed

    Yuskaitis, Christopher J; Parviz, Mahsa; Loui, Psyche; Wan, Catherine Y; Pearl, Phillip L

    2015-08-01

    Music production and perception invoke a complex set of cognitive functions that rely on the integration of sensorimotor, cognitive, and emotional pathways. Pitch is a fundamental perceptual attribute of sound and a building block for both music and speech. Although the cerebral processing of pitch is not completely understood, recent advances in imaging and electrophysiology have provided insight into the functional and anatomical pathways of pitch processing. This review examines the current understanding of pitch processing and behavioral and neural variations that give rise to difficulties in pitch processing, and potential applications of music education for language processing disorders such as dyslexia.

  4. Subcortical neural representation to Mandarin pitch contours in American and Chinese newborns.

    PubMed

    Jeng, Fuh-Cherng; Lin, Chia-Der; Wang, Tang-Chuan

    2016-06-01

    Voice pitch carries important information for speech understanding. This study examines the neural representation of voice pitch at the subcortical level, as reflected by the scalp-recorded frequency-following responses from ten American and ten Chinese newborns. By utilizing a set of four distinctive Mandarin pitch contours that mimic the English vowel /yi/, the results indicate that the rising and dipping pitch contours produce significantly better tracking accuracy and larger response amplitudes than the falling pitch contour. This finding suggests a hierarchy of potential stimuli when testing neonates who are born in a tonal or non-tonal linguistic environment.

  5. Adolescent baseball pitching technique: lower extremity biomechanical analysis.

    PubMed

    Milewski, Matthew D; Õunpuu, Sylvia; Solomito, Matthew; Westwell, Melany; Nissen, Carl W

    2012-11-01

    Documentation of the lower extremity motion patterns of adolescent pitchers is an important part of understanding the pitching motion and the implication of lower extremity technique on upper extremity loads, injury and performance. The purpose of this study was to take the initial step in this process by documenting the biomechanics of the lower extremities during the pitching cycle in adolescent pitchers and to compare these findings with the published data for older pitchers. Three-dimensional motion analysis using a comprehensive lower extremity model was used to evaluate the fast ball pitch technique in adolescent pitchers. Thirty-two pitchers with a mean age of 12.4 years (range 10.5-14.7 years) and at least 2 years of experience were included in this study. The pitchers showed a mean of 49 ± 12° of knee flexion of the lead leg at foot contact. They tended to maintain this position through ball release, and then extended their knee during the follow through phase (ball release to maximal internal glenohumeral rotation). The lead leg hip rapidly progressed into adduction and flexion during the arm cocking phase with a range of motion of 40 ± 10° adduction and 30 ± 13° flexion. The lead hip mean peak adduction velocity was 434 ± 83°/s and flexion velocity was 456 ± 156°/s. Simultaneously, the trailing leg hip rapidly extended approaching to a mean peak extension of -8 ± 5° at 39% of the pitch cycle, which is close to passive range of motion constraints. Peak hip abduction of the trailing leg at foot contact was -31 ± 12°, which also approached passive range of motion constraints. Differences and similarities were also noted between the adolescent lower extremity kinematics and adult pitchers; however, a more comprehensive analysis using similar methods is needed for a complete comparison.

  6. Process for tertiary oil recovery using tall oil pitch

    DOEpatents

    Radke, Clayton J.

    1985-01-01

    Compositions and process employing same for enhancing the recovery of residual acid crudes, particularly heavy crudes, by injecting a composition comprising caustic in an amount sufficient to maintain a pH of at least about 11, preferably at least about 13, and a small but effective amount of a multivalent cation for inhibiting alkaline silica dissolution with the reservoir. Preferably a tall oil pitch soap is included and particularly for the heavy crudes a polymeric mobility control agent.

  7. Unsteady Flow Separation and Attachment Induced by Pitching Airfoils

    DTIC Science & Technology

    1983-01-13

    dynamic stall. The oc- er may remain totally laminar prior :o seoaration , curronce and severity of dyvnamic stall is directly and this, by definition...in **Professor, iep.Artrent of *..rospace Lnziner- pitch direction of the airfoil were achieved v’ine in Scicnces. ,mal I os, ill.it ion anrles ( .-5...Variables for Hotwire Study The creat ion and f.te of the highly synchro- nized, strcn; vor:ccit’-.,-rc carefully charictrrizzed Feynulds Reduced Mean

  8. Light airplane crash tests at three pitch angles

    NASA Technical Reports Server (NTRS)

    Vaughan, V. L., Jr.; Alfaro-Bou, E.

    1979-01-01

    Three similar twin-engine general aviation airplane specimens were crash tested at an impact dynamics research facility at 27 m/sec, a flight path angle of -15 deg, and pitch angles of -15 deg, 0 deg, and 15 deg. Other crash parameters were held constant. The test facility, instrumentation, test specimens, and test method are briefly described. Structural damage and accelerometer data for each of the three impact conditions are presented and discussed.

  9. Sidewall spacer quadruple patterning for 15nm half-pitch

    NASA Astrophysics Data System (ADS)

    Xu, Ping; Chen, Yongmei; Chen, Yijian; Miao, Liyan; Sun, Shiyu; Kim, Sung-Woo; Berger, Ami; Mao, Daxin; Bencher, Christ; Hung, Raymond; Ngai, Chris

    2011-04-01

    193nm immersion lithography, with the single-exposure resolution limitation of half-pitch 38nm, has extended its patterning capability to about 20nm using the double-patterning technique[1]. Despite the non-trivial sub-20nm patterning challenges, several NAND Flash manufacturers are already pursuing for sub-16nm patterning technology. 25nm NAND flash memory has already begun production in 2010, and given the typical 2-year scaling cycle, sub-16nm NAND devices should see pilot or mass production as early as 2014. Using novel patterning techniques such as sidewall spacer quadruple patterning (upon 120nm to 128nm pitch using dry ArF lithography) or triple patterning (upon 90nm pitch using immersion ArF lithography), we are able to extend optical lithography to sub-16nm half-pitch and demonstrate the lithographic performance that can nearly meet the ITRS roadmap requirements. In this paper, we conduct an in-depth review and demonstration of sidewall spacer quadruple patterning; including 300mm wafer level data of the mean values and CDU along with a mathematical assessment of the various data pools for sub-16nm lines and spaces. By understanding which processes (lithography, deposition, and etch) define the critical dimension of each data pool, we can make predictions of CDU capability for the sidewall spacer quad patterning. Our VeritySEM4i CD SEM tool demonstrated high measurement yield during fully automated measurements, which enables accurate lines, spaces and CDU measurements of the sub-16nm. The patterns generated from the sidewall spacer quadruple patterning techniques are used as a hardmask to transfer sub-16nm lines and spaces patterns to underneath amorphous silicon and silicon oxide layers, or poly silicon layer for 1X STI or poly gate applications.

  10. Baseball Pitching Biomechanics in Relation to Injury Risk and Performance

    PubMed Central

    Fortenbaugh, Dave; Fleisig, Glenn S.; Andrews, James R.

    2009-01-01

    Context: Baseball pitching kinematics, kinetics, ball velocity, and injuries at the shoulder and elbow are related. Evidence Acquisition: PubMed and Sport Discus were searched for original studies published between 1994 and 2008. Relevant references in these studies were retrieved. Inferential studies that tested relationships between kinematics and kinetics were included, as were studies that tested relationships between kinematics and ball velocity. Descriptive studies that simply quantified kinematics and/or kinetics were excluded. Results: Several kinematic parameters at the instant of foot contact were associated with increased upper extremity kinetics: front foot position, front foot orientation, shoulder abduction, and shoulder horizontal adduction. The timing of shoulder external rotation, pelvis rotation, and upper trunk rotation was associated with increased kinetics and decreased ball velocity. Low braking force of the lead leg and a short stride were associated with decreased ball velocity. Decreased maximum shoulder external rotation, shoulder abduction, knee extension, and trunk tilt were also associated with decreased ball velocity. As pitchers develop, kinematic values remain similar, their variability reduces, and kinetic values gradually increase. Slight kinematic variations were seen among pitch types, although the kinetics of fastballs and curveballs were relatively the same; changeup kinetics were the lowest. As pitchers fatigued, kinetic values remained constant, but increases in arm pain were reported. Conclusions: Several kinematic parameters were related to joint kinetics and ball velocity. To enhance performance and reduce injury risk, pitchers need to learn proper fastball mechanics at an early age. A changeup is recommended as a safe secondary pitch to complement the fastball; the curveball can be added after fastball and changeup mechanics are mastered. Avoiding overuse and pitching while fatigued is necessary to minimize the risk of

  11. Pitch-Scale Modification using the Modulated Aspiration Noise Source

    DTIC Science & Technology

    2006-09-21

    processing tool Praat , which arrives at a periodicity measure by a forward cross-correlation analysis [12]. The pitch value is also needed in the...cussion. 8. References K. N. Stevens, Acoustic Phonetics . Cambridge, MA: MIT Press, 1998. Y. Stylianou, J. Laroche, and E. Moulines, "High...components in speech," IEEE Transactions on Speech and Audio Processing, vol. 9, no. 7, pp. 713-726, 2001. ] " Praat ," version 4.4.04. P. Boersma and D. Weenink.

  12. Process for tertiary oil recovery using tall oil pitch

    SciTech Connect

    Radke, C. J.

    1985-07-02

    Compositions and process employing same for enhancing the recovery of residual acid crudes, particularly heavy crudes, by injecting a composition comprising caustic in an amount sufficient to maintain a pH of at least about 11, preferably at least about 13, and a small but effective amount of a multivalent cation for inhibiting alkaline silica dissolution with the reservoir. Preferably a tall oil pitch soap is included and particularly for the heavy crudes a polymeric mobility control agent.

  13. Design principles for Bernal spirals and helices with tunable pitch

    NASA Astrophysics Data System (ADS)

    Fejer, Szilard N.; Chakrabarti, Dwaipayan; Kusumaatmaja, Halim; Wales, David J.

    2014-07-01

    Using the framework of potential energy landscape theory, we describe two in silico designs for self-assembling helical colloidal superstructures based upon dipolar dumbbells and Janus-type building blocks, respectively. Helical superstructures with controllable pitch length are obtained using external magnetic field driven assembly of asymmetric dumbbells involving screened electrostatic as well as magnetic dipolar interactions. The pitch of the helix is tuned by modulating the Debye screening length over an experimentally accessible range. The second design is based on building blocks composed of rigidly linked spheres with short-range anisotropic interactions, which are predicted to self-assemble into Bernal spirals. These spirals are quite flexible, and longer helices undergo rearrangements via cooperative, hinge-like moves, in agreement with experiment.Using the framework of potential energy landscape theory, we describe two in silico designs for self-assembling helical colloidal superstructures based upon dipolar dumbbells and Janus-type building blocks, respectively. Helical superstructures with controllable pitch length are obtained using external magnetic field driven assembly of asymmetric dumbbells involving screened electrostatic as well as magnetic dipolar interactions. The pitch of the helix is tuned by modulating the Debye screening length over an experimentally accessible range. The second design is based on building blocks composed of rigidly linked spheres with short-range anisotropic interactions, which are predicted to self-assemble into Bernal spirals. These spirals are quite flexible, and longer helices undergo rearrangements via cooperative, hinge-like moves, in agreement with experiment. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr00324a

  14. Pitch Wetting on Model Basal and Edge-Plane Surfaces

    DTIC Science & Technology

    2004-06-04

    spin coating and then utilize the films as model substrates for pitch wetting studies. Experimental Films from indanthrone disulfonate (Optiva...Inc. South San Francisco) were formed on quartz from 7.5 wt% aqueous solution either by spin coating (rotation rate: 500 rmp for 20 seconds and then...formed by spin coating (Figs. 3,4) and Meyer-bar-coating (Fig. 5) of indanthrone disulfonate aqueous solutions followed by drying and direct

  15. Impact absorbing blade mounts for variable pitch blades

    NASA Technical Reports Server (NTRS)

    Ravenhall, R.; Salemme, C. T.; Adamson, A. P. (Inventor)

    1977-01-01

    A variable pitch blade and blade mount are reported that are suitable for propellers, fans and the like and which have improved impact resistance. Composite fan blades and blade mounting arrangements permit the blades to pivot relative to a turbine hub about an axis generally parallel to the centerline of the engine upon impact of a large foreign object, such as a bird. Centrifugal force recovery becomes the principal energy absorbing mechanism and a blade having improved impact strength is obtained.

  16. Accuracy of pitch matching significantly improved by live voice model.

    PubMed

    Granot, Roni Y; Israel-Kolatt, Rona; Gilboa, Avi; Kolatt, Tsafrir

    2013-05-01

    Singing is, undoubtedly, the most fundamental expression of our musical capacity, yet an estimated 10-15% of Western population sings "out-of-tune (OOT)." Previous research in children and adults suggests, albeit inconsistently, that imitating a human voice can improve pitch matching. In the present study, we focus on the potentially beneficial effects of the human voice and especially the live human voice. Eighteen participants varying in their singing abilities were required to imitate in singing a set of nine ascending and descending intervals presented to them in five different randomized blocked conditions: live piano, recorded piano, live voice using optimal voice production, recorded voice using optimal voice production, and recorded voice using artificial forced voice production. Pitch and interval matching in singing were much more accurate when participants repeated sung intervals as compared with intervals played to them on the piano. The advantage of the vocal over the piano stimuli was robust and emerged clearly regardless of whether piano tones were played live and in full view or were presented via recording. Live vocal stimuli elicited higher accuracy than recorded vocal stimuli, especially when the recorded vocal stimuli were produced in a forced vocal production. Remarkably, even those who would be considered OOT singers on the basis of their performance when repeating piano tones were able to pitch match live vocal sounds, with deviations well within the range of what is considered accurate singing (M=46.0, standard deviation=39.2 cents). In fact, those participants who were most OOT gained the most from the live voice model. Results are discussed in light of the dual auditory-motor encoding of pitch analogous to that found in speech.

  17. Dynamical features of the wake behind a pitching foil.

    PubMed

    Deng, Jian; Sun, Liping; Shao, Xueming

    2015-12-01

    As an extension of the previous study on the three-dimensional transition of the wake behind a pitching foil [Deng and Caulfield, Phys. Rev. E 91, 043017 (2015)], this investigation draws a comprehensive map on the pitching frequency-amplitude phase space. First, by fixing the Reynolds number at Re=1700 and varying the pitching frequency and amplitude, we identify three key dynamical features of the wake: first, the transition from Bénard-von Kármán (BvK) vortex streets to reverse BvK vortex streets, and second, the symmetry breaking of this reverse BvK wake leading to a deflected wake, and a further transition from two-dimensional (2D) wakes to three-dimensional (3D) wakes. The transition boundary between the 2D and 3D wakes lies top right of the wake deflection boundary, implying a correlation between the wake deflection and the 2D to 3D wake transition, confirming that this transition occurs after the wake deflection. This paper supports the previous extensive numerical studies under two-dimensional assumption at low Reynolds number, since it is indeed two dimensional except for the cases at very high pitching frequencies or large amplitudes. Furthermore, by three-dimensional direct numerical simulations (DNSs), we confirm the previous statement about the physical realizability of the short wavelength mode at β=30 (or λ(z)=0.21) for Re=1500. By comparing the three-dimensional vortical structures by DNSs with that from the reconstruction of Floquet modes, we find a good consistency between them, both exhibiting clear streamwise structures in the wake.

  18. Pitch-Angle Diffusion in Canonical Coordinates: A Theoretical Formulation.

    DTIC Science & Technology

    1981-08-21

    begenerated from the above set by procedures analogous to the Rayleigh- Schr ~ dinger perturbation theory used in quantum mechanics. The avail-ability...the time -independent Schrbdinger equation (d 2 gn/d 2 ) + k g n = 0. (30) This is achieved by introducing the new variable =f (Dzz/Dz,z,)dz’, (31) 0...Radiation Belts 20 VISTRACT (Continu, on reveres aide if neesseary and Identify by block numb.,) -4he equation for pitch-angle diffusion (at constant

  19. Pitch-based short carbon fiber. Final report

    SciTech Connect

    Lin, S.S.

    1991-12-01

    Short carbon fiber manufactured from coal tar pitch by Osaka Gas Co. is examined by chemical composition analysis, X-ray powder diffraction, optical microscope, and electron spectroscopic techniques. The present analytical results are compared with the data obtainable from other sources. Owing to the low cost of the short fiber, it is recommended that the fiber could be used for a wide variety of reinforcement applications such as, cement/concrete mixtures, polymer composites, and high temperature materials. Processing includes the mechanical separation of mesophase microbeads of three to 30 micron diameters from crude coal tar during three heat treatment stages. The mesophases obtained are then subjected to solvent extraction, hydrogenation, and polymerization to yield isotropic and anisotropic pitches suitable for melt spinning. The short fiber is fabricated from isotropic pitch by the rotary gas jet method, and the process yields a higher quality fiber as compared to other melt spinning methods. The most important feature is that this process is highly cost effective.

  20. Absolute and relative pitch: Global versus local processing of chords.

    PubMed

    Ziv, Naomi; Radin, Shulamit

    2014-01-01

    Absolute pitch (AP) is the ability to identify or produce notes without any reference note. An ongoing debate exists regarding the benefits or disadvantages of AP in processing music. One of the main issues in this context is whether the categorical perception of pitch in AP possessors may interfere in processing tasks requiring relative pitch (RP). Previous studies, focusing mainly on melodic and interval perception, have obtained inconsistent results. The aim of the present study was to examine the effect of AP and RP separately, using isolated chords. Seventy-three musicians were categorized into four groups of high and low AP and RP, and were tested on two tasks: identifying chord types (Task 1), and identifying a single note within a chord (Task 2). A main effect of RP on Task 1 and an interaction between AP and RP in reaction times were found. On Task 2 main effects of AP and RP, and an interaction were found, with highest performance in participants with both high AP and RP. Results suggest that AP and RP should be regarded as two different abilities, and that AP may slow down reaction times for tasks requiring global processing.

  1. Pitching effects of buoyancy during four competitive swimming strokes.

    PubMed

    Cohen, Raymond C Z; Cleary, Paul W; Harrison, Simon M; Mason, Bruce R; Pease, David L

    2014-10-01

    The purpose of this study was to determine the pitching effects of buoyancy during all competitive swimming strokes--freestyle, backstroke, butterfly, and breaststroke. Laser body scans of national-level athletes and synchronized multiangle swimming footage were used in a novel markerless motion capture process to produce three-dimensional biomechanical models of the swimming athletes. The deforming surface meshes were then used to calculate swimmer center-of-mass (CoM) positions, center-of-buoyancy (CoB) positions, pitch buoyancy torques, and sagittal plane moments of inertia (MoI) throughout each stroke cycle. In all cases the mean buoyancy torque tended to raise the legs and lower the head; however, during part of the butterfly stroke the instantaneous buoyancy torque had the opposite effect. The swimming strokes that use opposing arm and leg strokes (freestyle and backstroke) had smaller variations in CoM positions, CoB positions, and buoyancy torques. Strokes with synchronized left-right arm and leg movement (butterfly and breaststroke) had larger variations in buoyancy torques, which impacts the swimmer's ability to maintain a horizontal body pitch for these strokes. The methodology outlined in this paper enables the rotational effects of buoyancy to be better understood by swimmers, allowing better control of streamlined horizontal body positioning during swimming to improve performance.

  2. Pitch discrimination in cerebellar patients: evidence for a sensory deficit.

    PubMed

    Parsons, Lawrence M; Petacchi, Augusto; Schmahmann, Jeremy D; Bower, James M

    2009-12-15

    In the last two decades, a growing body of research showing cerebellar involvement in an increasing number of nonmotor tasks and systems has prompted an expansion of speculations concerning the function of the cerebellum. Here, we tested the predictions of a hypothesis positing cerebellar involvement in sensory data acquisition. Specifically, we examined the effect of global cerebellar degeneration on primary auditory sensory function by means of a pitch discrimination task. The just noticeable difference in pitch between two tones was measured in 15 healthy controls and in 15 high functioning patients afflicted with varying degrees of global cerebellar degeneration caused by hereditary, idiopathic, paraneoplastic, or postinfectious pancerebellitis. Participants also performed an auditory detection task assessing sustained attention, a test of verbal auditory working memory, and an audiometric test. Patient pitch discrimination thresholds were on average five and a half times those of controls and were proportional to the degree of cerebellar ataxia assessed independently. Patients and controls showed normal hearing thresholds and similar performance in control tasks in sustained attention and verbal auditory working memory. These results suggest there is an effect of cerebellar degeneration on primary auditory function. The findings are consistent with other recent demonstrations of cerebellar-related sensory impairments, and with robust cerebellar auditorily evoked activity, confirmed by quantitative meta-analysis, across a range of functional neuroimaging studies dissociated from attention, motor, affective, and cognitive variables. The data are interpreted in the context of a sensory hypothesis of cerebellar function.

  3. Aerodynamic Control of a Pitching Airfoil using Distributed Active Bleed

    NASA Astrophysics Data System (ADS)

    Kearney, John; Glezer, Ari

    2012-11-01

    Aero-effected flight control using distributed active bleed driven by pressure differences across lifting surface and regulated by integrated louver actuators is investigated in wind tunnel experiments. The interaction between unsteady bleed and the cross flows alters the apparent aerodynamic shape of the lifting surface by regulating the accumulation and shedding of vorticity concentrations, and consequently the distributions of forces and moments. The present experiments are conducted using a 2-D dynamically-pitching VR-7 airfoil model from pre- to post-stall angles of attack. The effects of leading edge bleed at high angles of attack on the formation and evolution of the dynamic stall vorticity concentrations are investigated at high reduced frequencies (k > 0.1) using PIV phase-locked to the airfoil's motion. The time-dependent bleed enables broad-range variation in lift and pitching moment with significant extension of the stall margin. In particular, bleed actuation reduces the extent of ``negative damping'' or pitching moment instability with minimal lift penalty. Supported by NTRC-VLRCOE, monitored by Dr. Mike Rutkowski.

  4. Which Direction Is up for a High Pitch?

    PubMed

    Carnevale, Michael J; Harris, Laurence R

    2016-01-01

    Low- and high-pitched sounds are perceptually associated with low and high visuospatial elevations, respectively. The spatial properties of this association are not well understood. Here we report two experiments that investigated whether low and high tones can be used as spatial cues to upright for self-orientation and identified the spatial frame(s) of reference used in perceptually binding auditory pitch to visuospatial 'up' and 'down'. In experiment 1, participants' perceptual upright (PU) was measured while lying on their right side with and without high- and low-pitched sounds played through speakers above their left ear and below their right ear. The sounds were ineffective in moving the perceived upright from a direction intermediate between the body and gravity towards the direction indicated by the sounds. In experiment 2, we measured the biasing effects of ascending and descending tones played through headphones on ambiguous vertical or horizontal visual motion created by combining gratings drifting in opposite directions while participants either sat upright or laid on their right side. Ascending and descending tones biased the interpretation of ambiguous motion along both the gravitational vertical and the long-axis of the body with the strongest effect along the body axis. The combination of these two effects showed that axis of maximum effect of sound corresponded approximately to the direction of the perceptual upright, compatible with the idea that 'high' and 'low' sounds are defined along this axis.

  5. Self-propulsion of a heaving and pitching flexible flag

    NASA Astrophysics Data System (ADS)

    Kim, Boyoung; Park, Sung Goon; Sung, Hyung Jin

    2015-11-01

    Flapping motions of flexible flags are widespread in nature. Birds, fish, and insects use their wings, fins, or bodies to stay afloat and to advance forward in the surrounding fluids. In the present study, a self-propelled flexible flag with heaving and pitching motions in a quiescent flow has been simulated by using the immersed boundary method. The flexible flag can move freely in the horizontal direction and the body of the flexible flag moves passively along the head. The motion of the head of the flag was described as a harmonic heaving oscillation in the vertical direction. The motion of the angle of the head was described as a harmonic oscillation with a moving clamped condition for the heaving and pitching flag. The cruising speed and the swimming efficiency of the self-propelled flag were determined as functions of the bending coefficient (γ) , the heaving amplitude (Ah) , the pitching amplitude (Ap) , the heaving frequency (St), and the phase difference (Δϕ) between Ah and Ap. We conducted a parametric study on the optimized the cruising speed and the swimming efficiency with respect to γ, St, Ah, Ap, and Δϕ

  6. Absolute and relative pitch: Global versus local processing of chords

    PubMed Central

    Ziv, Naomi; Radin, Shulamit

    2014-01-01

    Absolute pitch (AP) is the ability to identify or produce notes without any reference note. An ongoing debate exists regarding the benefits or disadvantages of AP in processing music. One of the main issues in this context is whether the categorical perception of pitch in AP possessors may interfere in processing tasks requiring relative pitch (RP). Previous studies, focusing mainly on melodic and interval perception, have obtained inconsistent results. The aim of the present study was to examine the effect of AP and RP separately, using isolated chords. Seventy-three musicians were categorized into four groups of high and low AP and RP, and were tested on two tasks: identifying chord types (Task 1), and identifying a single note within a chord (Task 2). A main effect of RP on Task 1 and an interaction between AP and RP in reaction times were found. On Task 2 main effects of AP and RP, and an interaction were found, with highest performance in participants with both high AP and RP. Results suggest that AP and RP should be regarded as two different abilities, and that AP may slow down reaction times for tasks requiring global processing. PMID:24855499

  7. Trunk axial rotation in baseball pitching and batting.

    PubMed

    Fleisig, Glenn S; Hsu, Wellington K; Fortenbaugh, Dave; Cordover, Andrew; Press, Joel M

    2013-11-01

    The purpose of this study was to quantify trunk axial rotation and angular acceleration in pitching and batting of elite baseball players. Healthy professional baseball pitchers (n = 40) and batters (n = 40) were studied. Reflective markers attached to each athlete were tracked at 240 Hz with an eight-camera automated digitizing system. Trunk axial rotation was computed as the angle between the pelvis and the upper trunk in the transverse plane. Trunk angular acceleration was the second derivative of axial rotation. Maximum trunk axial rotation (55 +/- 6 degrees) and angular acceleration (11,600 +/- 3,100 degrees/s2) in pitching occurred before ball release, approximately at the instant the front foot landed. Maximum trunk axial rotation (46 +/- 9 degrees) and angular acceleration (7,200 +/- 2,800 degrees/s2) in batting occurred in the follow-through after ball contact. Thus, the most demanding instant for the trunk and spine was near front foot contact for pitching and after ball contact for batting.

  8. Pitching Emotions: The Interpersonal Effects of Emotions in Professional Baseball

    PubMed Central

    Cheshin, Arik; Heerdink, Marc W.; Kossakowski, Jolanda J.; Van Kleef, Gerben A.

    2016-01-01

    Sports games are inherently emotional situations, but surprisingly little is known about the social consequences of these emotions. We examined the interpersonal effects of emotional expressions in professional baseball. Specifically, we investigated whether pitchers’ facial displays influence how pitches are assessed and responded to. Using footage from the Major League Baseball World Series finals, we isolated incidents where the pitcher’s face was visible before a pitch. A pre-study indicated that participants consistently perceived anger, happiness, and worry in pitchers’ facial displays. An independent sample then predicted pitch characteristics and batter responses based on the same perceived emotional displays. Participants expected pitchers perceived as happy to throw more accurate balls, pitchers perceived as angry to throw faster and more difficult balls, and pitchers perceived as worried to throw slower and less accurate balls. Batters were expected to approach (swing) when faced with a pitcher perceived as happy and to avoid (no swing) when faced with a pitcher perceived as worried. Whereas previous research focused on using emotional expressions as information regarding past and current situations, our work suggests that people also use perceived emotional expressions to predict future behavior. Our results attest to the impact perceived emotional expressions can have on professional sports. PMID:26909062

  9. Perceptual grouping affects pitch judgments across time and frequency.

    PubMed

    Borchert, Elizabeth M O; Micheyl, Christophe; Oxenham, Andrew J

    2011-02-01

    Pitch, the perceptual correlate of fundamental frequency (F0), plays an important role in speech, music, and animal vocalizations. Changes in F0 over time help define musical melodies and speech prosody, while comparisons of simultaneous F0 are important for musical harmony, and for segregating competing sound sources. This study compared listeners' ability to detect differences in F0 between pairs of sequential or simultaneous tones that were filtered into separate, nonoverlapping spectral regions. The timbre differences induced by filtering led to poor F0 discrimination in the sequential, but not the simultaneous, conditions. Temporal overlap of the two tones was not sufficient to produce good performance; instead performance appeared to depend on the two tones being integrated into the same perceptual object. The results confirm the difficulty of comparing the pitches of sequential sounds with different timbres and suggest that, for simultaneous sounds, pitch differences may be detected through a decrease in perceptual fusion rather than an explicit coding and comparison of the underlying F0s.

  10. Neural correlates of consonance, dissonance, and the hierarchy of musical pitch in the human brainstem.

    PubMed

    Bidelman, Gavin M; Krishnan, Ananthanarayan

    2009-10-21

    Consonant and dissonant pitch relationships in music provide the foundation of melody and harmony, the building blocks of Western tonal music. We hypothesized that phase-locked neural activity within the brainstem may preserve information relevant to these important perceptual attributes of music. To this end, we measured brainstem frequency-following responses (FFRs) from nonmusicians in response to the dichotic presentation of nine musical intervals that varied in their degree of consonance and dissonance. Neural pitch salience was computed for each response using temporally based autocorrelation and harmonic pitch sieve analyses. Brainstem responses to consonant intervals were more robust and yielded stronger pitch salience than those to dissonant intervals. In addition, the ordering of neural pitch salience across musical intervals followed the hierarchical arrangement of pitch stipulated by Western music theory. Finally, pitch salience derived from neural data showed high correspondence with behavioral consonance judgments (r = 0.81). These results suggest that brainstem neural mechanisms mediating pitch processing show preferential encoding of consonant musical relationships and, furthermore, preserve the hierarchical pitch relationships found in music, even for individuals without formal musical training. We infer that the basic pitch relationships governing music may be rooted in low-level sensory processing and that an encoding scheme that favors consonant pitch relationships may be one reason why such intervals are preferred behaviorally.

  11. Fine-pitch control in EB lithography for semiconductor laser grating formation

    NASA Astrophysics Data System (ADS)

    Hisa, Yoshihiro; Minami, Hiroyuki; Shibata, Kimitaka; Takemoto, Akira; Sato, Kazuhiko; Nagahama, Kouki; Otsubo, Mutuyuki; Aiga, Masao

    1996-05-01

    Grating-pitch accuracy is studied from minimum pitch variation point of view. The pitches of the gratings delineated at the focus range from -50micrometers to +50micrometers and stitching errors between subfields are evaluated using an EB machine which features a long distance between the deflector and the wafer stage. The grating pitch variation is realized by using a deflection amplitude control. It is confirmed that errors of the pitches due to defocus are less than 0.05 nm, and the deviations from nominal setting of the pitch are also less than 0.1 nm when the pitches are varied from -6 percent to +6 percent at 0.1 percent step.

  12. A Fröhlich effect and representational gravity in memory for auditory pitch.

    PubMed

    Hubbard, Timothy L; Ruppel, Susan E

    2013-08-01

    Memory for the initial pitch of an auditory target that increased or decreased in auditory frequency was examined. Memory was displaced forward in the direction of pitch motion, and this is consistent with the Fröhlich effect previously observed for visual targets moving in visual physical space. The Fröhlich effect for pitch increased with faster target velocity and decreased if an auditory cue with the same pitch as the initial pitch of the target was presented before the target was presented. The Fröhlich effect was larger for descending pitch motion than for ascending pitch motion, and this is consistent with an influence of representational gravity. The data suggest that representation of auditory frequency space exhibits some of the same biases as representation of visual physical space, and implications for theories of attention in displacement and for crossmodal and multisensory representation of space are discussed.

  13. Toward Adaptability: Where to from Here?

    ERIC Educational Resources Information Center

    Parsons, Seth A.; Vaughn, Margaret

    2016-01-01

    In this article, the collection of articles in this issue are synthesized to discuss conceptualizations of adaptive teaching as a means to foster spaces for adaptive teaching in today's complex educational system. Themes that exist across this collection of articles include adaptive teachers as constructivists, adaptive teachers as knowledgeable…

  14. Maximum speed of pitch change and how it may relate to speech

    NASA Astrophysics Data System (ADS)

    Xu, Yi; Sun, Xuejing

    2002-03-01

    How fast speakers can change pitch voluntarily is potentially an important articulatory constraint for speech production. Previous attempts at assessing the maximum speed of pitch change have helped improve understanding of certain aspects of pitch production in speech. However, since only ``response time''-time needed to complete the middle 75% of a pitch shift-was measured in previous studies, direct comparisons with speech data have been difficult. In the present study, a new experimental paradigm was adopted in which subjects produced rapid successions of pitch shifts by imitating synthesized model pitch undulation patterns. This permitted the measurement of the duration of entire pitch shifts. Native speakers of English and Mandarin participated as subjects. The speed of pitch change was measured both in terms of response time and excursion time-time needed to complete the entire pitch shift. Results show that excursion time is nearly twice as long as response time. This suggests that physiological limitation on the speed of pitch movement is greater than has been recognized. Also, it is found that the maximum speed of pitch change varies quite linearly with excursion size, and that it is different for pitch rises and falls. Comparisons of present data with data on speed of pitch change from studies of real speech found them to be largely comparable. This suggests that the maximum speed of pitch change is often approached in speech, and that the role of physiological constraints in determining the shape and alignment of F0 contours in speech is probably greater than has been appreciated.

  15. Tilt and Translation Motion Perception during Pitch Tilt with Visual Surround Translation

    NASA Technical Reports Server (NTRS)

    O'Sullivan, Brita M.; Harm, Deborah L.; Reschke, Millard F.; Wood, Scott J.

    2006-01-01

    The central nervous system must resolve the ambiguity of inertial motion sensory cues in order to derive an accurate representation of spatial orientation. Previous studies suggest that multisensory integration is critical for discriminating linear accelerations arising from tilt and translation head motion. Visual input is especially important at low frequencies where canal input is declining. The NASA Tilt Translation Device (TTD) was designed to recreate postflight orientation disturbances by exposing subjects to matching tilt self motion with conflicting visual surround translation. Previous studies have demonstrated that brief exposures to pitch tilt with foreaft visual surround translation produced changes in compensatory vertical eye movement responses, postural equilibrium, and motion sickness symptoms. Adaptation appeared greatest with visual scene motion leading (versus lagging) the tilt motion, and the adaptation time constant appeared to be approximately 30 min. The purpose of this study was to compare motion perception when the visual surround translation was inphase versus outofphase with pitch tilt. The inphase stimulus presented visual surround motion one would experience if the linear acceleration was due to foreaft self translation within a stationary surround, while the outofphase stimulus had the visual scene motion leading the tilt by 90 deg as previously used. The tilt stimuli in these conditions were asymmetrical, ranging from an upright orientation to 10 deg pitch back. Another objective of the study was to compare motion perception with the inphase stimulus when the tilts were asymmetrical relative to upright (0 to 10 deg back) versus symmetrical (10 deg forward to 10 deg back). Twelve subjects (6M, 6F, 22-55 yrs) were tested during 3 sessions separated by at least one week. During each of the three sessions (out-of-phase asymmetrical, in-phase asymmetrical, inphase symmetrical), subjects were exposed to visual surround translation

  16. Friction and wear of PAN/pitch-, PAN/CVI- and pitch/resin/CVI-based carbon/carbon composites

    NASA Astrophysics Data System (ADS)

    Chen, J. D.; Ju, C. P.

    1994-05-01

    We compared the tribological behavior under a high speed condition (1.7 MPa, 2000 rev/min) of six different carbon/carbon composites including three two-dimensional PAN/pitch composites (TH, TM, and TL), one two-dimensional PAN/CVI composite (E), one two-dimensional pitch/resin/CVI composite (A), and one three-dimensional PAN/pitch composite (T3D). Results indicated that, among the five two-dimensional composites, TM and E performed significantly better than the other three composites under the present condition. Both TM and E exhibited a reasonably low friction coefficient (both about 0.4) and a wear rate that was an order of magnitude lower than those of the other three. A transition in friction occurred for A, TH, and TM, but not for E or TL. The pretransitional friction coefficients of the three composites were 0.1-0.2, similar to those measured under the low speed condition. During transition, the initially formed thin, smooth lubricative film was suddenly disrupted and turned into a thick powdery debris layer that caused the friction coefficient to rise abruptly to 0.5-0.9. The powdery debris on TM and E was easily 'ironed' into a smooth and tight lubricative film to cause both friction and wear to decline. The three-dimensional composite T3D was not suitable for high speed applications owing to extensive structural damage.

  17. TH-C-18A-12: Evaluation of the Impact of Body Size and Tube Output Limits in the Optimization of Fast Scanning with High-Pitch Dual Source CT

    SciTech Connect

    Ramirez Giraldo, J; Mileto, A.; Hurwitz, L.; Marin, D.

    2014-06-15

    Purpose: To evaluate the impact of body size and tube power limits in the optimization of fast scanning with high-pitch dual source CT (DSCT). Methods: A previously validated MERCURY phantom, made of polyethylene, with circular cross-section of diameters 16, 23, 30 and 37cm, and connected through tapered sections, was scanned using a second generation DSCT system. The DSCT operates with two independently controlled x-ray tube generators offering up to 200 kW power reserve (100 kW per tube). The entire length of the phantom (42cm) was scanned with two protocols using: A)Standard single-source CT (SSCT) protocol with pitch of 0.8, and B) DSCT protocol with high-pitch values ranging from 1.6 to 3.2 (0.2 steps). All scans used 120 kVp with 150 quality reference mAs using automatic exposure control. Scanner radiation output (CTDIvol) and effective mAs values were extracted retrospectively from DICOM files for each slice. Image noise was recorded. All variables were assessed relative to phantom diameter. Results: With standard-pitch SSCT, the scanner radiation output (and tube-current) were progressively adapted with increasing size, from 6 mGy (120 mAs) up to 15 mGy (270 mAs) from the thinnest (16cm) to the thickest diameter (37 cm), respectively. By comparison, using high-pitch (3.2), the scanner output was bounded at about 8 mGy (140 mAs), independent of phantom diameter. Although relative to standard-pitch, the high-pitch led to lower radiation output for the same scan, the image noise was higher, particularly for larger diameters. To match the radiation output adaptation of standard-pitch, a high-pitch mode of 1.6 was needed, with the advantage of scanning twice as fast. Conclusion: To maximize the benefits of fast scanning with high-pitch DSCT, the body size and tube power limits of the system need to be considered such that a good balance between speed of acquisition and image quality are warranted. JCRG is an employee of Siemens Medical Solutions USA Inc.

  18. Disturbance observer based pitch control of wind turbines for disturbance rejection

    NASA Astrophysics Data System (ADS)

    Yuan, Yuan; Chen, Xu; Tang, Jiong

    2016-04-01

    In this research, a disturbance observer based (DOB) control scheme is illustrated to reject the unknown low frequency disturbances to wind turbines. Specifically, we aim at maintaining the constant output power but achieving better generator speed regulation when the wind turbine is operated at time-varying and turbulent wind field. The disturbance observer combined with a filter is designed to asymptotically reject the persistent unknown time-varying disturbances. The proposed algorithm is tested in both linearized and nonlinear NREL offshore 5-MW baseline wind turbine. The application of this DOB pitch controller achieves improved power and speed regulation in Region 3 compared with a baseline gain scheduling PID collective controller both in linearized and nonlinear plant.

  19. Modern methods for investigating the stability of a pitching floating platform wind turbine

    NASA Astrophysics Data System (ADS)

    Lennie, Matthew; Marten, David; Pechlivanoglou, George; Navid Nayeri, Christian; Paschereit, Christian Oliver

    2016-09-01

    The QBlade implementation of the Lifting Line Free Vortex Wake method(LLFVW) was tested in conditions analogous to floating platform motion. Comparisons against two independent test cases, using a variety of simulation methods show excellent agreement in thrust forces, rotor power, blade forces and rotor plane induction. Along with the many verifications already undertaken in literature, it seems that the code performs solidly even in these challenging cases. Further to this, the key steps are presented from a new formulation of the instantaneous aerodynamic thrust damping of a wind turbine rotor. A test case with harmonic platform motion and collective pitch is used to demonstrate how combining such tools can lead to better understanding of aeroelastic stability.

  20. Experimental Investigation of the Unsteady Flow Structures of Two Interacting Pitching Wings

    NASA Astrophysics Data System (ADS)

    Kurt, Melike; Moored, Keith

    2015-11-01

    Birds, insects and fish propel themselves with unsteady motions of their wings and fins. Many of these animals are also found to fly or swim in three-dimensional flocks and schools. Numerous studies have explored the three-dimensional steady flow interactions and the two-dimensional unsteady flow interactions in collectives. Yet, the characterization of the three-dimensional unsteady interactions remains relatively unexplored. This study aims to characterize the flow structures and interactions between two sinusoidally pitching finite-span wings. The arrangement of the wings varies from a tandem to a bi-plane configuration. The vortex structures for these various arrangements are quantified by using particle image velocimetry. The vortex-wing interactions are also characterized as the synchrony between the wings is modified.

  1. Efficient passive pitching motion caused by elastic deformation in flexible flapping wing MAVs

    NASA Astrophysics Data System (ADS)

    Nguyen, Trong; Truong, Tien; Yeo, Khoon Seng; Lim, Tee Tai

    2015-11-01

    Computational and experimental models which mimic Hawkmoth wings were constructed to investigate the effects of wing flexibility. The wing actuation mechanism is minimal with only one degree of freedom in sweeping motion with neither active pitching nor elevation. Despite the simplicity of the imparted motion, the wing models in both computations and experiments delivered convincing deformation features such as wing twisting and camber which closely resembles the ones observed in real Hawkmoth wings. The generated aerodynamic forces are remarkable both in magnitude and efficiency. The study hence reveals that a complicated actuation mechanism might not be required to produce the sophisticated and efficient motion of insect wings, which in fact could be the result of collective elastic deformation thanks to their highly optimized structure mainly comprised of well-organized veins and membranes.

  2. Test of a fine pitch SOI pixel detector with laser beam

    NASA Astrophysics Data System (ADS)

    Liu, Yi; Lu, Yunpeng; Ju, Xudong; Qun, Ou-Yang

    2016-01-01

    A silicon pixel detector with fine pitch size of 19 μm × 19 μm, developed based on SOI (silicon-on-insulator) technology, was tested under the illumination of infrared laser pulses. As an alternative method for particle beam tests, the laser pulses were tuned to very short duration and small transverse profile to simulate the tracks of MIPs (minimum ionization particles) in silicon. Hit cluster sizes were measured with focused laser pulses propagating through the SOI detector perpendicular to its surface and most of the induced charge was found to be collected inside the seed pixel. For the first time, the signal amplitude as a function of the applied bias voltage was measured for this SOI detector, deepening understanding of its depletion characteristics. Supported by National Natural Science Foundation of China (11375226)

  3. The relationship between age and baseball pitching kinematics in professional baseball pitchers.

    PubMed

    Dun, Shouchen; Fleisig, Glenn S; Loftice, Jeremy; Kingsley, David; Andrews, James R

    2007-01-01

    Joint range of motion and physical capacities have been shown to change with age in both throwing athletes and non-athletes. The age of professional baseball pitchers could span from late teens to mid-40s. However, the effects of age on the pitching kinematics among professional baseball pitchers are still unknown. In this study, 67 healthy professional baseball pitchers were tested using a 3D motion analysis system. Their mean age was 23.7+/-3.3 years (range 18.8-34.4). The 12 pitchers more than one standard deviation older than the mean (i.e., older than 27.0 years) were categorized into the older group, and the 10 pitchers more than one standard deviation younger than the mean (i.e., younger than 20.4 years) were defined as the younger group. In all, 18 kinematic variables (14 position and 4 velocity) were calculated, and Student's t-tests were used to compare the variables between the two groups. Six position variables were found to be significantly different between the two groups. At the instant of lead foot contact, the older group had a shorter stride, a more closed pelvis orientation, and a more closed upper trunk orientation. The older group also produced less shoulder external rotation during the arm cocking phase, more lead knee flexion at ball release, and less forward trunk tilt at ball release. Ball velocity and body segment velocity variables showed no significant differences between the two groups. Thus, differences in specific pitching kinematic variables among professional baseball pitchers of different age groups were not associated with significant differences in ball velocities between groups. The current results suggest that both biological changes and technique adaptations occur during the career of a professional baseball pitcher.

  4. Characterization of coal- and petroleum-derived binder pitches and the interaction of pitch/coke mixtures in pre-baked carbon anodes

    NASA Astrophysics Data System (ADS)

    Suriyapraphadilok, Uthaiporn

    Carbon anodes are manufactured from calcined petroleum coke (i.e. sponge coke) and recycled anode butts as fillers, and coal tar pitch (SCTP) as the binder. During the manufacturing of carbon anodes, coal tar pitch is mixed with calcined petroleum coke. The mix of binder, filler and some additives is heated to about 50°C above the softening point of the pitch, typically 160°C. This temperature is sufficient to enable the pitch to wet the coke particles. The mix is then either extruded, vibrated, or pressed to form a green anode. The binding between coke and pitch is very important to the anode properties. There are different binder pitches used in this work, which were standard coal tar pitch (SCTP-2), petroleum pitch (PP-1), gasification pitch (GP-115), coal-extract pitch (WVU-5), and co-coking pitches (HTCCP and OXCCP). Petroleum pitch is a residue produced from heat-treatment and distillation of petroleum fractions. Production of coal-extract pitch involves a prehydrogenation of coal followed by extraction using a dipolar solvent. Gasification pitches are distilled by-product tars produced from the coal gasification process. Co-coking pitch was developed in this work and was obtained from the liquid distillate of co-coking process of coal and heavy petroleum residue. Understanding of composition and structures of pitches from different sources and processes would lead to greater understanding of the binding properties of pitch in carbon anodes and was one of the main focuses in this study. Characterization of pitches by using different techniques including gas chromatography/mass spectrometry (GC/MS), high performance liquid chromatography (HPLC), matrix-assisted laser desorption ionization/mass spectrometry (MALDI/MS), 1H and 13C solution-state nuclear magnetic resonance (NMR), and 13C solid-state NMR yield important chemistry and structural information. The binding, or in other words the interactions in the pitch/coke mixture, is another interest in this

  5. Differential Recognition of Pitch Patterns in Discrete and Gliding Stimuli in Congenital Amusia: Evidence from Mandarin Speakers

    ERIC Educational Resources Information Center

    Liu, Fang; Xu, Yi; Patel, Aniruddh D.; Francart, Tom; Jiang, Cunmei

    2012-01-01

    This study examined whether "melodic contour deafness" (insensitivity to the direction of pitch movement) in congenital amusia is associated with specific types of pitch patterns (discrete versus gliding pitches) or stimulus types (speech syllables versus complex tones). Thresholds for identification of pitch direction were obtained using discrete…

  6. Ultrasonic longitudinal wave velocity in carbon-carbon Pitch and Pitch/M2 shape stable nosetip material from 70/sup 0/F to 5400/sup 0/F

    SciTech Connect

    Gieske, J.H.

    1985-06-01

    A pulse echo method was used in two notched rods of carbon-carbon Pitch material and one rod of Pitch/M2 shape stable nosetip material to measure the temperature dependence of the longitudinal wave velocity from room temperature to 5400/sup 0/F. The velocity was constant to within 2% of the room temperature value for the Pitch parent material throughout the temperature range. For the Pitch/M2 material, the velocity increased to a maximum of 10% at 4000/sup 0/F and then decreased rapidly. Room temperature velocities in the principal directions of the composite are also given for the two Pitch rods, which showed a 15% decrease in velocity near the ends of both rods and near the side of one rod.

  7. In Vitro Cellular Adaptations of Indicators of Longevity in Response to Treatment with Serum Collected from Humans on Calorie Restricted Diets

    PubMed Central

    Allard, Joanne S.; Heilbronn, Leonie K.; Smith, Carolina; Hunt, Nicole D.; Ingram, Donald K.; Ravussin, Eric; de Cabo, Rafael

    2008-01-01

    Calorie restriction (CR) produces several health benefits and increases lifespan in many species. Studies suggest that alternate-day fasting (ADF) and exercise can also provide these benefits. Whether CR results in lifespan extension in humans is not known and a direct investigation is not feasible. However, phenotypes observed in CR animals when compared to ad libitum fed (AL) animals, including increased stress resistance and changes in protein expression, can be simulated in cells cultured with media supplemented with blood serum from CR and AL animals. Two pilot studies were undertaken to examine the effects of ADF and CR on indicators of health and longevity in humans. In this study, we used sera collected from those studies to culture human hepatoma cells and assessed the effects on growth, stress resistance and gene expression. Cells cultured in serum collected at the end of the dieting period were compared to cells cultured in serum collected at baseline (before the dieting period). Cells cultured in serum from ADF participants, showed a 20% increase in Sirt1 protein which correlated with reduced triglyceride levels. ADF serum also induced a 9% decrease in proliferation and a 25% increase in heat resistance. Cells cultured in serum from CR participants induced an increase in Sirt1 protein levels by 17% and a 30% increase in PGC-1α mRNA levels. This first in vitro study utilizing human serum to examine effects on markers of health and longevity in cultured cells resulted in increased stress resistance and an up-regulation of genes proposed to be indicators of increased longevity. The use of this in vitro technique may be helpful for predicting the potential of CR, ADF and other dietary manipulations to affect markers of longevity in humans. PMID:18791640

  8. Where music meets space: Children's sensitivity to pitch intervals is related to their mental spatial transformation skills.

    PubMed

    Möhring, Wenke; Ramsook, Kizzann Ashana; Hirsh-Pasek, Kathryn; Golinkoff, Roberta M; Newcombe, Nora S

    2016-06-01

    Relations have been found among various continuous dimensions, including space and musical pitch. To probe the nature and development of space-pitch mappings, we tested 5- to 7-year-olds and adults (N=69), who heard pitch intervals and were asked to choose the corresponding spatial representation. Results showed that children and adults both mapped pitches continuously onto space, although effects were stronger in older than younger children. Additionally, children's spatial and numerical skills were tested, showing a relation between children's spatial and pitch-matching skills, and between their spatial and numerical skills. However, pitch and number were not related, suggesting spatial underpinnings for pitch and number.

  9. Aerodynamic Response of a Pitching Airfoil with Pulsed Circulation Control for Vertical Axis Wind Turbine Applications

    NASA Astrophysics Data System (ADS)

    Panther, Chad C.

    Vertical Axis Wind Turbines (VAWTs) have experienced a renewed interest in development for urban, remote, and offshore applications. Past research has shown that VAWTs cannot compete with Horizontals Axis Wind Turbines (HAWTs) in terms of energy capture efficiency. VAWT performance is plagued by dynamic stall (DS) effects at low tip-speed ratios (lambda), where each blade pitches beyond static stall multiple times per revolution. Furthermore, for lambda<2, blades operate outside of stall during over 70% of rotation. However, VAWTs offer many advantages such as omnidirectional operation, ground proximity of generator, lower sound emission, and non-cantilevered blades with longer life. Thus, mitigating dynamic stall and improving VAWT blade aerodynamics for competitive power efficiency has been a popular research topic in recent years and the directive of this study. Past research at WVU focused on the addition of circulation control (CC) technology to improve VAWT aerodynamics and expand the operational envelope. A novel blade design was generated from the augmentation of a NACA0018 airfoil to include CC capabilities. Static wind tunnel data was collected for a range of steady jet momentum coefficients (0.01≤ Cmu≤0.10) for analytical vortex model performance projections. Control strategies were developed to optimize CC jet conditions throughout rotation, resulting in improved power output for 2≤lambda≤5. However, the pumping power required to produce steady CC jets reduced net power gains of the augmented turbine by approximately 15%. The goal of this work was to investigate pulsed CC jet actuation to match steady jet performance with reduced mass flow requirements. To date, no experimental studies have been completed to analyze pulsed CC performance on a pitching airfoil. The research described herein details the first study on the impact of steady and pulsed jet CC on pitching VAWT blade aerodynamics. Both numerical and experimental studies were

  10. Are pitch and roll compensations required in all pathologies? A data analysis of 2945 fractions

    PubMed Central

    Mancosu, Pietro; Gaudino, Anna; Lobefalo, Francesca; Paganini, Lucia; Palumbo, Valentina; Stravato, Antonella; Tomatis, Stefano; Scorsetti, Marta

    2015-01-01

    Objective: New linear accelerators can be equipped with a 6D robotic couch, providing two additional rotational motion axes: pitch and roll. These shifts in kilo voltage–cone beam CT (kV-CBCT) image-guided radiotherapy (IGRT) were evaluated over the first 6 months of usage of a 6D robotic couch-top, ranking the treatment sites for which the two compensations are larger for patient set-up. Methods: The couch compensations of 2945 fractions for 376 consecutive patients treated on the PerfectPitch™ 6D couch (Varian® Medical Systems, Palo Alto, CA) were analysed. Among these patients, 169 were treated for brain, 111 for lung, 54 for liver, 26 for pancreas and 16 for prostate tumours. During the set-up, patient anatomy from planning CT was aligned to kV-CBCT, and 6D movements were executed. Information related to pitch and roll were extracted by proper querying of the Microsoft® SQL server (Microsoft Corporation, Redmond, WA) ARIA database (Varian Medical Systems). Mean values and standard deviations were calculated for all sites. Kolmogorov–Smirnov (KS) test was performed. Results: Considering all the data, mean pitch and roll adjustments were −0.10° ± 0.92° and 0.12° ± 0.96°, respectively; mean absolute values for both adjustments were 0.58° ± 0.69° and 0.69° ± 0.72°, respectively. Brain treatments showed the highest mean absolute values for pitch and roll rotations (0.73° ± 0.69° and 0.80° ± 0.78°, respectively); the lowest values of 0.36° ± 0.47° and 0.49° ± 0.58° were found for pancreas. KS test was significant for brain vs liver, pancreas and prostate. Collective corrections (pitch + roll) >0.5°, >1.0° and >2.0° were observed in, respectively, 79.8%, 61.0% and 29.1% for brain and 56.7%, 39.4% and 6.7% for pancreas. Conclusion: Adjustments in all six dimensions, including unconventional pitch and roll rotations, improve the patient set-up in all treatment sites. The greatest improvement was

  11. Preparation of low toxicity pitches by thermal oxidative condensation of anthracene oil.

    PubMed

    Alvarez, Patricia; Granda, Marcos; Sutil, Juan; Santamaría, Ricardo; Blanco, Clara; Menéndez, Rosa; José Fernández, Juan; Viña, José Antonio

    2009-11-01

    This article describes a novel industrial procedure for producing new pitches of low toxicity from anthracene oil, a byproduct of coal tar distillation. The procedure involves oxidative treatment in order to polymerize and condense the anthracene oil components followed by thermal treatment and distillation in order to obtain a pitch with the desired parameters. This sequence (oxidative treatment/thermal treatment/distillation) was repeated four times under reaction conditions of increasing severity in four cycles of anthracene oil processing to obtain the four pitches. The pitches had similar characteristics to those of standard binder coal tar pitches (e.g., softening point and wetting capacity). Because of the inherent composition of the parent anthracene oil, the pitches were found to be totally free of solid particles, i.e., primary quinoline insolubles and metals. The gas chromatography and gas chromatography/mass spectroscopy results revealed a consecutive decrease in toxicity with successive cycles of anthracene oil processing. Thus, the benzo[a]pyrene content decreased from 11.2 mg/g for the pitch in cycle one to 1.5 mg/g for the pitch with four processing cycles. The carcinogenicity of the pitches, evaluated on the basis of benzo[a]pyrene toxic equivalency factors, also followed the same tendency. The final carcinogenity values are nearly all lower than those of standard binder coal tar pitches.

  12. Pitch Processing in Children with Williams Syndrome: Relationships between Music and Prosody Skills.

    PubMed

    Martínez-Castilla, Pastora; Sotillo, María

    2014-05-15

    Williams syndrome (WS), a genetic neurodevelopmental disorder, has been taken as evidence that music and language constitute separate modules. This research focused on the linguistic component of prosody and aimed to assess whether relationships exist between the pitch processing mechanisms for music and prosody in WS. Children with WS and typically developing individuals were presented with a musical pitch and two prosody discrimination tasks. In the musical pitch discrimination task, participants were required to distinguish whether two musical tones were the same or different. The prosody discrimination tasks evaluated participants' skills for discriminating pairs of prosodic contours based on pitch or pitch, loudness and length, jointly. In WS, musical pitch discrimination was significantly correlated with performance on the prosody task assessing the discrimination of prosodic contours based on pitch only. Furthermore, musical pitch discrimination skills predicted performance on the prosody task based on pitch, and this relationship was not better explained by chronological age, vocabulary or auditory memory. These results suggest that children with WS process pitch in music and prosody through shared mechanisms. We discuss the implications of these results for theories of cognitive modularity. The implications of these results for intervention programs for individuals with WS are also discussed.

  13. The perception of complex pitch in cochlear implants: A comparison of monopolar and tripolar stimulation.

    PubMed

    Fielden, Claire A; Kluk, Karolina; Boyle, Patrick J; McKay, Colette M

    2015-10-01

    Cochlear implant listeners typically perform poorly in tasks of complex pitch perception (e.g., musical pitch and voice pitch). One explanation is that wide current spread during implant activation creates channel interactions that may interfere with perception of temporal fundamental frequency information contained in the amplitude modulations within channels. Current focusing using a tripolar mode of stimulation has been proposed as a way of reducing channel interactions, minimising spread of excitation and potentially improving place and temporal pitch cues. The present study evaluated the effect of mode in a group of cochlear implant listeners on a pitch ranking task using male and female singing voices separated by either a half or a quarter octave. Results were variable across participants, but on average, pitch ranking was at chance level when the pitches were a quarter octave apart and improved when the difference was a half octave. No advantage was observed for tripolar over monopolar mode at either pitch interval, suggesting that previously published psychophysical advantages for focused modes may not translate into improvements in complex pitch ranking. Evaluation of the spectral centroid of the stimulation pattern, plus a lack of significant difference between male and female voices, suggested that participants may have had difficulty in accessing temporal pitch cues in either mode.

  14. The role of pitch and temporal diversity in the perception and production of musical sequences.

    PubMed

    Prince, Jon B; Pfordresher, Peter Q

    2012-10-01

    In two experiments we explored how the dimensions of pitch and time contribute to the perception and production of musical sequences. We tested how dimensional diversity (the number of unique categories in each dimension) affects how pitch and time combine. In Experiment 1, 18 musically trained participants rated the complexity of sequences varying only in their diversity in pitch or time; a separate group of 18 pianists reproduced these sequences after listening to them without practice. Overall, sequences with more diversity were perceived as more complex, but pitch diversity influenced ratings more strongly than temporal diversity. Further, although participants perceived sequences with high levels of pitch diversity as more complex, errors were more common in the sequences with higher diversity in time. Sequences in Experiment 2 exhibited diversity in both pitch and time; diversity levels were a subset of those tested in Experiment 1. Again diversity affected complexity ratings and errors, but there were no statistical interactions between dimensions. Nonetheless, pitch diversity was the primary factor in determining perceived complexity, and again temporal errors occurred more often than pitch errors. Additionally, diversity in one dimension influenced error rates in the other dimension in that both error types were more frequent relative to Experiment 1. These results suggest that although pitch and time do not interact directly, they are nevertheless not processed in an informationally encapsulated manner. The findings also align with a dimensional salience hypothesis, in which pitch is prioritised in the processing of typical Western musical sequences.

  15. Language-experience plasticity in neural representation of changes in pitch salience.

    PubMed

    Krishnan, Ananthanarayan; Gandour, Jackson T; Suresh, Chandan H

    2016-04-15

    Neural representation of pitch-relevant information at the brainstem and cortical levels of processing is influenced by language experience. A well-known attribute of pitch is its salience. Brainstem frequency following responses and cortical pitch specific responses, recorded concurrently, were elicited by a pitch salience continuum spanning weak to strong pitch of a dynamic, iterated rippled noise pitch contour-homolog of a Mandarin tone. Our aims were to assess how language experience (Chinese, English) affects i) enhancement of neural activity associated with pitch salience at brainstem and cortical levels, ii) the presence of asymmetry in cortical pitch representation, and iii) patterns of relative changes in magnitude along the pitch salience continuum. Peak latency (Fz: Na, Pb, and Nb) was shorter in the Chinese than the English group across the continuum. Peak-to-peak amplitude (Fz: Na-Pb, Pb-Nb) of the Chinese group grew larger with increasing pitch salience, but an experience-dependent advantage was limited to the Na-Pb component. At temporal sites (T7/T8), the larger amplitude of the Chinese group across the continuum was both limited to the Na-Pb component and the right temporal site. At the brainstem level, F0 magnitude gets larger as you increase pitch salience, and it too reveals Chinese superiority. A direct comparison of cortical and brainstem responses for the Chinese group reveals different patterns of relative changes in magnitude along the pitch salience continuum. Such differences may point to a transformation in pitch processing at the cortical level presumably mediated by local sensory and/or extrasensory influence overlaid on the brainstem output.

  16. Genomic expression catalogue of a global collection of BCG vaccine strains show evidence for highly diverged metabolic and cell-wall adaptations

    PubMed Central

    Abdallah, Abdallah M.; Hill-Cawthorne, Grant A.; Otto, Thomas D.; Coll, Francesc; Guerra-Assunção, José Afonso; Gao, Ge; Naeem, Raeece; Ansari, Hifzur; Malas, Tareq B.; Adroub, Sabir A.; Verboom, Theo; Ummels, Roy; Zhang, Huoming; Panigrahi, Aswini Kumar; McNerney, Ruth; Brosch, Roland; Clark, Taane G.; Behr, Marcel A.; Bitter, Wilbert; Pain, Arnab

    2015-01-01

    Although Bacillus Calmette-Guérin (BCG) vaccines against tuberculosis have been available for more than 90 years, their effectiveness has been hindered by variable protective efficacy and a lack of lasting memory responses. One factor contributing to this variability may be the diversity of the BCG strains that are used around the world, in part from genomic changes accumulated during vaccine production and their resulting differences in gene expression. We have compared the genomes and transcriptomes of a global collection of fourteen of the most widely used BCG strains at single base-pair resolution. We have also used quantitative proteomics to identify key differences in expression of proteins across five representative BCG strains of the four tandem duplication (DU) groups. We provide a comprehensive map of single nucleotide polymorphisms (SNPs), copy number variation and insertions and deletions (indels) across fourteen BCG strains. Genome-wide SNP characterization allowed the construction of a new and robust phylogenic genealogy of BCG strains. Transcriptional and proteomic profiling revealed a metabolic remodeling in BCG strains that may be reflected by altered immunogenicity and possibly vaccine efficacy. Together, these integrated-omic data represent the most comprehensive catalogue of genetic variation across a global collection of BCG strains. PMID:26487098

  17. Describing baseball pitch movement with right-hand rules.

    PubMed

    Bahill, A Terry; Baldwin, David G

    2007-07-01

    The right-hand rules show the direction of the spin-induced deflection of baseball pitches: thus, they explain the movement of the fastball, curveball, slider and screwball. The direction of deflection is described by a pair of right-hand rules commonly used in science and engineering. Our new model for the magnitude of the lateral spin-induced deflection of the ball considers the orientation of the axis of rotation of the ball relative to the direction in which the ball is moving. This paper also describes how models based on somatic metaphors might provide variability in a pitcher's repertoire.

  18. Graded pitch electromagnetic pump for thin strip metal casting systems

    DOEpatents

    Kuznetsov, Stephen B.

    1986-01-01

    A metal strip casing system is provided with an electromagnetic pump which includes a pair of primary blocks having a graded pole pitch, polyphase ac winding and being arranged on opposite sides of a movable heat sink. A nozzle is provided for depositing liquid metal on the heat sink such that the resulting metal strip and heat sink combination is subjected to a longitudinal electromagnetic field which increases in wavelength in the direction of travel of the heat sink, thereby subjecting the metal and heat sink to a longitudinal force having a magnitude which increases in the direction of travel.

  19. Graded pitch electromagnetic pump for thin strip metal casting systems

    DOEpatents

    Kuznetsov, S.B.

    1986-04-01

    A metal strip casing system is provided with an electromagnetic pump which includes a pair of primary blocks having a graded pole pitch, polyphase ac winding and being arranged on opposite sides of a movable heat sink. A nozzle is provided for depositing liquid metal on the heat sink such that the resulting metal strip and heat sink combination is subjected to a longitudinal electromagnetic field which increases in wavelength in the direction of travel of the heat sink, thereby subjecting the metal and heat sink to a longitudinal force having a magnitude which increases in the direction of travel. 4 figs.

  20. Magnetic alignment of mesophase pitch-based carbon fibers

    NASA Astrophysics Data System (ADS)

    Matthews, M. J.; Dresselhaus, M. S.; Dresselhaus, G.; Endo, M.; Nishimura, Y.; Hiraoka, T.; Tamaki, N.

    1996-07-01

    Mesophase pitch-based carbon fibers (MPCFs) have recently been developed for use as high performance anode materials in Li ion secondary batteries, having a microscopic as well as macroscopic structure especially suitable for Li storage. Because of the highly anisotropic diamagnetic moment observed between 50 and 310 K in pristine milled MPCF segments, they can easily be oriented parallel to an applied magnetic field, as observed by scanning electron microscopy. A simple model is proposed to explain both the observed alignment of undoped fibers and the suppression of alignment in B-doped MPCFs for relatively small applied magnetic fields, because of their smaller diamagnetic moment.

  1. Star tracker error analysis: Roll-to-pitch nonorthogonality

    NASA Technical Reports Server (NTRS)

    Corson, R. W.

    1979-01-01

    An error analysis is described on an anomaly isolated in the star tracker software line of sight (LOS) rate test. The LOS rate cosine was found to be greater than one in certain cases which implied that either one or both of the star tracker measured end point unit vectors used to compute the LOS rate cosine had lengths greater than unity. The roll/pitch nonorthogonality matrix in the TNB CL module of the IMU software is examined as the source of error.

  2. Adaptive State Predictor Based Human Operator Modeling on Longitudinal and Lateral Control

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Gregory, Irene M.; Hempley, Lucas E.

    2015-01-01

    Control-theoretic modeling of the human operator dynamic behavior in manual control tasks has a long and rich history. In the last two decades, there has been a renewed interest in modeling the human operator. There has also been significant work on techniques used to identify the pilot model of a given structure. The purpose of this research is to attempt to go beyond pilot identification based on collected experimental data and to develop a predictor of pilot behavior. An experiment was conducted to categorize these interactions of the pilot with an adaptive controller compensating during control surface failures. A general linear in-parameter model structure is used to represent a pilot. Three different estimation methods are explored. A gradient descent estimator (GDE), a least squares estimator with exponential forgetting (LSEEF), and a least squares estimator with bounded gain forgetting (LSEBGF) used the experiment data to predict pilot stick input. Previous results have found that the GDE and LSEEF methods are fairly accurate in predicting longitudinal stick input from commanded pitch. This paper discusses the accuracy of each of the three methods - GDE, LSEEF, and LSEBGF - to predict both pilot longitudinal and lateral stick input from the flight director's commanded pitch and bank attitudes.

  3. Single channel speech separation in modulation frequency domain based on a novel pitch range estimation method

    NASA Astrophysics Data System (ADS)

    Mahmoodzadeh, Azar; Abutalebi, Hamid Reza; Soltanian-Zadeh, Hamid; Sheikhzadeh, Hamid

    2012-12-01

    Computational Auditory Scene Analysis (CASA) has been the focus in recent literature for speech separation from monaural mixtures. The performance of current CASA systems on voiced speech separation strictly depends on the robustness of the algorithm used for pitch frequency estimation. We propose a new system that estimates pitch (frequency) range of a target utterance and separates voiced portions of target speech. The algorithm, first, estimates the pitch range of target speech in each frame of data in the modulation frequency domain, and then, uses the estimated pitch range for segregating the target speech. The method of pitch range estimation is based on an onset and offset algorithm. Speech separation is performed by filtering the mixture signal with a mask extracted from the modulation spectrogram. A systematic evaluation shows that the proposed system extracts the majority of target speech signal with minimal interference and outperforms previous systems in both pitch extraction and voiced speech separation.

  4. A versatile pitch tracking algorithm: from human speech to killer whale vocalizations.

    PubMed

    Shapiro, Ari Daniel; Wang, Chao

    2009-07-01

    In this article, a pitch tracking algorithm [named discrete logarithmic Fourier transformation-pitch detection algorithm (DLFT-PDA)], originally designed for human telephone speech, was modified for killer whale vocalizations. The multiple frequency components of some of these vocalizations demand a spectral (rather than temporal) approach to pitch tracking. The DLFT-PDA algorithm derives reliable estimations of pitch and the temporal change of pitch from the harmonic structure of the vocal signal. Scores from both estimations are combined in a dynamic programming search to find a smooth pitch track. The algorithm is capable of tracking killer whale calls that contain simultaneous low and high frequency components and compares favorably across most signal to noise ratio ranges to the peak-picking and sidewinder algorithms that have been used for tracking killer whale vocalizations previously.

  5. Aircraft seating comfort: the influence of seat pitch on passengers' well-being.

    PubMed

    Kremser, Florian; Guenzkofer, Fabian; Sedlmeier, Claudia; Sabbah, Olaf; Bengler, Klaus

    2012-01-01

    One of the most important factors influencing aircraft seating comfort in economy class, is legroom. In an airline interior mock up, with the ability to adjust the seat pitch in a range of 28 inches to 43 inches, a study to investigate the influence of seat pitch on passengers' well-being was conducted. In a pre-study, aspects of subjective postural sensations and spatial perception were identified, and a questionnaire was developed. In the main study, 30 subjects rated at different seat pitch settings the spatial perception and the ability of adopting and changing sitting postures. As a result a functional relationship between overall well-being, the subjects' anthropometry and seat pitch was developed. Furthermore it was identified, that there is a maximum overall well-being at a seat pitch of 34 inches to 40 inches, depending on the passengers' anthropometry. A further enlargement of seat pitch, led to a reduction of well-being.

  6. Technology for the production of Zero Q.I pitch from coal tar

    NASA Astrophysics Data System (ADS)

    Karthik, K.; Kumar, K. Rajesh; Rao, C. V. Nageswara; Kumar, B. Vinod; Murty, J. V. S.

    2013-06-01

    Zero Quinoline Insolubles (Q.I) pitch is a special type of pitch obtained from pre-treatment of coal tar, which is converted into pitch. This is used for impregnation of electrodes for improving the strength, electrical properties and also used as a pre-cursor for Mesophase pitch for producing Mesophase pitch based carbon fibers, carbon foam, and Meso carbon micro beads. This paper discusses the technology of Q.I separation from Coal Tar by using decantation of Coal Tar mixed with Heavy Creosote Oil (HC Oil) at different temperatures. By this method we were able to produce the Zero Q.I pitch with a Q.I value of 0.1%.

  7. A novel binaural pitch elicited by phase-modulated noise: MEG and psychophysical observations.

    PubMed

    Witton, Caroline; Hillebrand, Arjan; Furlong, Paul L; Henning, G Bruce

    2012-06-01

    Binaural pitches are auditory percepts that emerge from combined inputs to the ears but that cannot be heard if the stimulus is presented to either ear alone. Here, we describe a binaural pitch that is not easily accommodated within current models of binaural processing. Convergent magnetoencephalography (MEG) and psychophysical measurements were used to characterize the pitch, heard when band-limited noise had a rapidly changing interaural phase difference. Several interesting features emerged: First, the pitch was perceptually lateralized, in agreement with the lateralization of the evoked changes in MEG spectral power, and its salience depended on dichotic binaural presentation. Second, the frequency of the pure tone that matched the binaural pitch lay within a lower spectral sideband of the phase-modulated noise and followed the frequency of that sideband when the modulation frequency or center frequency and bandwidth of the noise changed. Thus, the binaural pitch depended on the processing of binaural information in that lower sideband.

  8. Comparison of Life Calculations for Oscillating Bearings Considering Individual Pitch Control in Wind Turbines

    NASA Astrophysics Data System (ADS)

    Schwack, F.; Stammler, M.; Poll, G.; Reuter, A.

    2016-09-01

    The fatigue life calculation of bearings under rotating conditions has been well researched and standardized. In contrast, for bearings in oscillating applications no international standards exist. As a result, pitch bearings in wind turbines are designed with different, non standardized approaches. Furthermore, the impact of individual pitch control on pitch bearings has not yet been studied. In this paper four approaches for fatigue life calculation will be applied and compared under individual pitch control conditions. For comparison, the loads and the bearing geometry of the reference turbine IWT 7.5 MW, which is individual pitch controlled, are used. This paper will show how the bearing life calculated by different approaches reacts to individual pitch control conditions. Furthermore, the factors for the modified rating life, according to the ABMA and ISO standards, which implement different operation conditions on the bearings in rotating applications, are calculated for the given loads and the given bearing geometry in oscillating applications.

  9. Pitch and Harmony in Gyorgy Ligeti's "Hamburg Concerto" and "Syzygy" for String Quartet

    NASA Astrophysics Data System (ADS)

    Corey, Charles

    The analysis component of this dissertation focuses on intricate and complex pitch relationships in Gyorgy Ligeti's last work, the Hamburg Concerto. This piece uses two distinct tuning systems---twelve tone equal temperament and just intonation---throughout its seven movements. Often, these two systems are used simultaneously, creating complex harmonic relationships. This combination allows Ligeti to exploit the unique features of each system and explore their relationships to each other. Ligeti's just intonation in the Hamburg Concerto comes mainly from the five French horns, who are instructed to keep their hands out of the bell to allow the instrument to sound its exact harmonics. The horns themselves, however, are tuned to varying different fundamentals, creating a constantly changing series of just-intoned pitches anchored above an equal-tempered bass. This method of generating just-intoned intervals adds a second layer to the relationship between equal temperament and just intonation. This paper focuses on creating ways to understand this relationship, and describing the ramifications of these tunings as they unfold throughout the piece. Ligeti very carefully crafts this work in a way that creates a balance between the systems. Research done at the Paul Sacher Stiftung has uncovered a significant collection of errors in the published score. Clearing up these discrepancies allows for a much more accurate and more informed analysis. Throughout this dissertation, mistakes are corrected, and several aspects of the score are clarified. The tuning systems are described, and a likely tuning scheme for the horns is posited. (The analytical component of the dissertation delves into the many varying intervals which all fit into one interval class---a feature that is best explored when two distinct tuning systems are juxtaposed.) A language is created herein to better understand these pitch relationships that fit neither into equal temperament nor just intonation. The

  10. High-Field Functional Imaging of Pitch Processing in Auditory Cortex of the Cat

    PubMed Central

    Butler, Blake E.; Hall, Amee J.; Lomber, Stephen G.

    2015-01-01

    The perception of pitch is a widely studied and hotly debated topic in human hearing. Many of these studies combine functional imaging techniques with stimuli designed to disambiguate the percept of pitch from frequency information present in the stimulus. While useful in identifying potential “pitch centres” in cortex, the existence of truly pitch-responsive neurons requires single neuron-level measures that can only be undertaken in animal models. While a number of animals have been shown to be sensitive to pitch, few studies have addressed the location of cortical generators of pitch percepts in non-human models. The current study uses high-field functional magnetic resonance imaging (fMRI) of the feline brain in an attempt to identify regions of cortex that show increased activity in response to pitch-evoking stimuli. Cats were presented with iterated rippled noise (IRN) stimuli, narrowband noise stimuli with the same spectral profile but no perceivable pitch, and a processed IRN stimulus in which phase components were randomized to preserve slowly changing modulations in the absence of pitch (IRNo). Pitch-related activity was not observed to occur in either primary auditory cortex (A1) or the anterior auditory field (AAF) which comprise the core auditory cortex in cats. Rather, cortical areas surrounding the posterior ectosylvian sulcus responded preferentially to the IRN stimulus when compared to narrowband noise, with group analyses revealing bilateral activity centred in the posterior auditory field (PAF). This study demonstrates that fMRI is useful for identifying pitch-related processing in cat cortex, and identifies cortical areas that warrant further investigation. Moreover, we have taken the first steps in identifying a useful animal model for the study of pitch perception. PMID:26225563

  11. A study of the pitching moments and the stability characteristics of monoplanes

    NASA Technical Reports Server (NTRS)

    Higgins, George J

    1934-01-01

    This note presents a study of the pitching moments and the stability characteristics of monoplanes. Expressions for the pitching-moment coefficient and the Diehl stability coefficient for the monoplane are developed, suitable for the use of airplane designers. The effective difference between the high-wing and low-wing types is portrayed and discussed. Comparisons between experimental and computed values are made. Charts for use in the solution of numerical values of the pitching-moment and stability coefficients are presented.

  12. Perception of pitch location within a speaker's F0 range

    NASA Astrophysics Data System (ADS)

    Honorof, Douglas N.; Whalen, D. H.

    2005-04-01

    Fundamental frequency (F0) is used for many purposes in speech, but its linguistic significance is based on its relation to the speaker's range, not its absolute value. While it may be that listeners can gauge a specific pitch relative to a speaker's range by recognizing it from experience, whether they can do the same for an unfamiliar voice is an open question. The present experiment explored that question. Twenty native speakers of English (10 male, 10 female) produced the vowel /opena/ with a spoken (not sung) voice quality at varying pitches within their own ranges. Listeners then judged, without familiarization or context, where each isolated F0 lay within each speaker's range. Correlations were high both for the entire range (0.721) and for the range minus the extremes (0.609). Correlations were somewhat higher when the F0s were related to the range of all the speakers, either separated by sex (0.830) or pooled (0.848), but several factors discussed here may help account for this pattern. Regardless, the present data provide strong support for the hypothesis that listeners are able to locate an F0 reliably within a range without external context or prior exposure to a speaker's voice. .

  13. Pitched and Yawed Circular Jets in Cross-Flow

    NASA Technical Reports Server (NTRS)

    Milanovic, Ivana M.; Zaman, K. B. M. Q.; Reddy, D. R. (Technical Monitor)

    2002-01-01

    Results from an experimental investigation of flow field generated by pitched and yawed jets discharging from a flat plate into a cross-flow are presented. The circular jet was pitched at alpha = 20 degrees and 45 degrees and yawed between beta = 0 degrees and 90 degrees in increments of 15 degrees. The measurements were performed with two X-wires providing all three components of velocity and turbulence intensity. These data were obtained at downstream locations of x = 3, 5, 10 and 20, where the distance x normalized by the jet diameter, is measured from the center of the orifice. Data for all configurations were acquired at a momentum-flux ratio J = 8. Additionally, for selected angles and locations, surveys were conducted for J = 1.5, 4, and 20. As expected, the jet penetration is found to be higher at larger alpha. With increasing beta the jet spreads more. The rate of reduction of peak streamwise vorticity, with the downstream distance is significantly lessened at higher alpha but is found to be practically independent of alpha. Thus, at the farthest measurement station x = 20, omega(sub xmax) is about five times larger for beta = 0 degrees compared to the levels at beta = 0 degrees. Streamwise velocity within the jet-vortex structure is found to depend on the parameter J. At J = 1.5 and 4, 'wake-like' velocity profiles are observed. In comparison, a 'jet-like' overshoot is present at higher J.

  14. Gray- and white-matter anatomy of absolute pitch possessors.

    PubMed

    Dohn, Anders; Garza-Villarreal, Eduardo A; Chakravarty, M Mallar; Hansen, Mads; Lerch, Jason P; Vuust, Peter

    2015-05-01

    Absolute pitch (AP), the ability to identify a musical pitch without a reference, has been examined behaviorally in numerous studies for more than a century, yet only a few studies have examined the neuroanatomical correlates of AP. Here, we used MRI and diffusion tensor imaging to investigate structural differences in brains of musicians with and without AP, by means of whole-brain vertex-wise cortical thickness (CT) analysis and tract-based spatial statistics (TBSS) analysis. APs displayed increased CT in a number of areas including the bilateral superior temporal gyrus (STG), the left inferior frontal gyrus, and the right supramarginal gyrus. Furthermore, we found higher fractional anisotropy in APs within the path of the inferior fronto-occipital fasciculus, the uncinate fasciculus, and the inferior longitudinal fasciculus. The findings in gray matter support previous studies indicating an increased left lateralized posterior STG in APs, yet they differ from previous findings of thinner cortex for a number of areas in APs. Finally, we found a relation between the white-matter results and the CT in the right parahippocampal gyrus. In this study, we present novel findings in AP research that may have implications for the understanding of the neuroanatomical underpinnings of AP ability.

  15. Dynamic heave-pitch analysis of air cushion landing systems

    NASA Technical Reports Server (NTRS)

    Captain, K. M.; Boghani, A. B.; Wormley, D. N.

    1975-01-01

    A program to develop analytical tools for evaluating the dynamic performance of Air Cushion Landing Systems (ACLS) is described. The heave (vertical) motion of the ACLS was analyzed, and the analysis was extended to cover coupled heave-pitch motions. The mathematical models developed are based on a fundamental analysis of the body dynamics and fluid mechanics of the aircraft-cushion-runway interaction. The air source characteristics, flow losses in the feeding ducts, trunk and cushion, the effects of fluid compressibility, and dynamic trunk deflections, including ground contact are considered. A computer program, based on the heave-pitch analysis, was developed to simulate the dynamic behavior of an ACLS during landing impact and taxi over an irregular runway. The program outputs include ACLS motions, loadings, pressures, and flows as a function of time. To illustrate program use, three basic types of simulations were carried out. The results provide an initial indication of ACLS performance during (1) a static drop, (2) landing impact, and (3) taxi over a runway irregularity.

  16. Pitch-based monaural segregation of reverberant speech.

    PubMed

    Roman, Nicoleta; Wang, DeLiang

    2006-07-01

    In everyday listening, both background noise and reverberation degrade the speech signal. Psychoacoustic evidence suggests that human speech perception under reverberant conditions relies mostly on monaural processing. While speech segregation based on periodicity has achieved considerable progress in handling additive noise, little research in monaural segregation has been devoted to reverberant scenarios. Reverberation smears the harmonic structure of speech signals, and our evaluations using a pitch-based segregation algorithm show that an increase in the room reverberation time causes degraded performance due to weakened periodicity in the target signal. We propose a two-stage monaural separation system that combines the inverse filtering of the room impulse response corresponding to target location and a pitch-based speech segregation method. As a result of the first stage, the harmonicity of a signal arriving from target direction is partially restored while signals arriving from other directions are further smeared, and this leads to improved segregation. A systematic evaluation of the system shows that the proposed system results in considerable signal-to-noise ratio gains across different conditions. Potential applications of this system include robust automatic speech recognition and hearing aid design.

  17. Analysis of Dynamic Stall Through Chirp Signal Pitch Excursions

    NASA Astrophysics Data System (ADS)

    Heintz, Kyle; Coleman, Dustin; Wicks, Michael; Corke, Thomas; Thomas, Flint

    2013-11-01

    An augmentation of the typical pitching airfoil experiment has been performed where the pitching frequency and amplitude are dynamically varied in a short-time event to produce a ``chirp'' trajectory, α (t) =α0 +α1 (t) sin (tω (t)) . The frequency evolution followed a Schroeder-phase relation, ω (t) =ωmin + K (ωmax -ωmin) . The frequencies ranged from 0.5 Hz to 30 Hz, resulting in reduced frequencies from 0.02 to 0.1. The free-stream Mach number ranged from Mach 0.4 to 0.6, giving chord Reynolds numbers from 5 ×105 to 3 ×106 . The airfoil was a NACA 23012 section shape that was fully instrumented with 31 flush-mounted high-bandwidth pressure transducers. The pressure transducer outputs were simultaneously sampled with the instantaneous angle of attack, α (t) . The motivation for this study was to compare dynamic stall under non-equilibrium conditions. A particular interest is on the flow features that occur when dynamically passing between light and deep stall regimes. The results include phase analysis of aerodynamic loads, wavelet-based spectral analysis, and the determination of the intra-cycle aerodynamic damping factors.

  18. A nonmusical paradigm for identifying absolute pitch possessors

    NASA Astrophysics Data System (ADS)

    Ross, David A.; Olson, Ingrid R.; Marks, Lawrence E.; Gore, John C.

    2004-09-01

    The ability to identify and reproduce sounds of specific frequencies is remarkable and uncommon. The etiology and defining characteristics of this skill, absolute pitch (AP), have been very controversial. One theory suggests that AP requires a specific type of early musical training and that the ability to encode and remember tones depends on these learned musical associations. An alternate theory argues that AP may be strongly dependent on hereditary factors and relatively independent of musical experience. To date, it has been difficult to test these hypotheses because all previous paradigms for identifying AP have required subjects to employ knowledge of musical nomenclature. As such, these tests are insensitive to the possibility of discovering AP in either nonmusicians or musicians of non-Western training. Based on previous literature in pitch memory, a paradigm is presented that is intended to distinguish between AP possessors and nonpossessors independent of the subjects' musical experience. The efficacy of this method is then tested with 20 classically defined AP possessors and 22 nonpossessors. Data from these groups strongly support the validity of the paradigm. The use of a nonmusical paradigm to identify AP may facilitate research into many aspects of this phenomenon.

  19. Pitch-controlled variable-speed wind turbine generation

    SciTech Connect

    Muljadi, E.; Butterfield, C.P.

    2000-03-01

    Wind energy is a viable option to complement other types of pollution-free generation. In the early development of wind energy, the majority of wind turbines were operated at constant speed. Recently, the number of variable-speed wind turbines installed in wind farms has increased and more wind turbine manufacturers are making variable-speed wind turbines. This paper covers the operation of variable-speed wind turbines with pitch control. The system the authors considered is controlled to generate maximum energy while minimizing loads. The maximization of energy was only carried out on a static basis and only drive train loads were considered as a constraint. In medium wind speeds, the generator and power converter control the wind turbine to capture maximum energy from the wind. In the high wind speed region, the wind turbine is controlled to maintain the aerodynamic power produced by the wind turbine. Two methods to adjust the aerodynamic power were investigated: pitch control and generator load control, both of which are employed to control the operation of the wind turbine. The analysis and simulation shows that the wind turbine can be operated at its optimum energy capture while minimizing the load on the wind turbine for a wide range of wind speeds.

  20. Bathymetric surveying with GPS and heave, pitch, and roll compensation

    USGS Publications Warehouse

    Work, P.A.; Hansen, M.; Rogers, W.E.

    1998-01-01

    Field and laboratory tests of a shipborne hydrographic survey system were conducted. The system consists of two 12-channel GPS receivers (one on-board, one fixed on shore), a digital acoustic fathometer, and a digital heave-pitch-roll (HPR) recorder. Laboratory tests of the HPR recorder and fathometer are documented. Results of field tests of the isolated GPS system and then of the entire suite of instruments are presented. A method for data reduction is developed to account for vertical errors introduced by roll and pitch of the survey vessel, which can be substantial (decimeters). The GPS vertical position data are found to be reliable to 2-3 cm and the fathometer to 5 cm in the laboratory. The field test of the complete system in shallow water (<2 m) indicates absolute vertical accuracy of 10-20 cm. Much of this error is attributed to the fathometer. Careful surveying and equipment setup can minimize systematic error and yield much smaller average errors.

  1. Determining Pitch-angle Diffusion Coefficients from Test Particle Simulations

    NASA Astrophysics Data System (ADS)

    Ivascenko, Alex; Lange, Sebastian; Spanier, Felix; Vainio, Rami

    2016-12-01

    The transport and acceleration of charged particles in turbulent media are topics of great interest in space physics and interstellar astrophysics. These processes are dominated by the scattering of particles off magnetic irregularities. The scattering process itself is usually described by small-angle scattering, with the pitch-angle coefficient {D}μ μ playing a major role. Since the diffusion coefficient {D}μ μ can be determined analytically only for the approximation of quasilinear theory, the determination of this coefficient from numerical simulations has become more important. So far these simulations have yielded particle tracks for small-scale scattering, which can then be interpreted using the running diffusion coefficients. This method has a limited range of validity. This paper presents two new methods that allow for the calculation of the pitch-angle diffusion coefficient from numerical simulations. These methods no longer analyze particle trajectories and instead examine the change of particle distribution functions. It is shown that these methods provide better resolved results and allow for the analysis of strong turbulence. The application of these methods to Monte Carlo simulations of particle scattering and hybrid MHD-particle simulations is presented. Both analysis methods are able to recover the diffusion coefficients used as input for the Monte Carlo simulations and provide better results in MHD simulations, especially for stronger turbulence.

  2. Blade pitch optimization methods for vertical-axis wind turbines

    NASA Astrophysics Data System (ADS)

    Kozak, Peter

    Vertical-axis wind turbines (VAWTs) offer an inherently simpler design than horizontal-axis machines, while their lower blade speed mitigates safety and noise concerns, potentially allowing for installation closer to populated and ecologically sensitive areas. While VAWTs do offer significant operational advantages, development has been hampered by the difficulty of modeling the aerodynamics involved, further complicated by their rotating geometry. This thesis presents results from a simulation of a baseline VAWT computed using Star-CCM+, a commercial finite-volume (FVM) code. VAWT aerodynamics are shown to be dominated at low tip-speed ratios by dynamic stall phenomena and at high tip-speed ratios by wake-blade interactions. Several optimization techniques have been developed for the adjustment of blade pitch based on finite-volume simulations and streamtube models. The effectiveness of the optimization procedure is evaluated and the basic architecture for a feedback control system is proposed. Implementation of variable blade pitch is shown to increase a baseline turbine's power output between 40%-100%, depending on the optimization technique, improving the turbine's competitiveness when compared with a commercially-available horizontal-axis turbine.

  3. Bifurcation analysis of aircraft pitching motions near the stability boundary

    NASA Technical Reports Server (NTRS)

    Hui, W. H.; Tobak, M.

    1984-01-01

    Bifuraction theory is used to analyze the nonlinear dynamic stability characteristics of an aircraft subject to single degree of freedom pitching-motion perturbations about a large mean angle of attack. The requisite aerodynamic information in the equations of motion is represented in a form equivalent to the response to finite-amplitude pitching oscillations about the mean angle of attack. This information is deduced from the case of infinitesimal-amplitude oscillations. The bifurcation theory analysis reveals that when the mean angle of attack is increased beyond a critical value at which the aerodynamic damping vanishes, new solutions representing finite-amplitude periodic motions bifurcate from the previously stable steady motion. The sign of a simple criterion, cast in terms of aerodynamic properties, determines whether the bifurcating solutions are stable (supercritical) or unstable (subcritical). For flat-plate airfoils flying at supersonic/hypersonic speed, the bifurcation is subcritical, implying either that exchanges of stability between steady and periodic motion are accompanied by hysteresis phenomena, or that potentially large aperiodic departures from steady motion may develop.

  4. Variability in baseball pitching biomechanics among various levels of competition.

    PubMed

    Fleisig, Glenn; Chu, Yungchien; Weber, Adam; Andrews, James

    2009-03-01

    The aim of this study was to compare within-individual variability in baseball pitching among various levels of competition. It was hypothesized that variability decreases as level of competition increases. Five fastballs were analysed for 93 healthy male baseball pitchers (20 youth, 19 high school, 20 college, 20 Minor League, and 14 Major League level pitchers). Eleven kinematic, four temporal, and six kinetic parameters were quantified with a 240-Hz automated digitizing system. Three multiple analyses of variance were used to compare individual standard deviations for kinematic, temporal, and kinetic parameters among the five competition levels. There was a significant overall difference in kinematics and in six of the eleven kinematic parameters analysed: foot placement, knee flexion, pelvis angular velocity, elbow flexion, shoulder external rotation, and trunk forward tilt. Individual standard deviations tended to be greatest for youth pitchers, and decreased for higher levels of competition. Thus pitchers who advanced to higher levels exhibited less variability in their motions. Differences in temporal variation were non-significant; thus variability in pitching coordination was not improved at higher levels. Differences in kinetic variation were non-significant, implying no particular skill level has increased risk of injury due to variation in joint kinetics.

  5. Characteristic ground-reaction forces in baseball pitching.

    PubMed

    MacWilliams, B A; Choi, T; Perezous, M K; Chao, E Y; McFarland, E G

    1998-01-01

    Overhand throwing requires contributions from and interaction between all limb segments. Most previous investigations have concentrated on the throwing arm itself, yet poor mechanics at the arm may originate in the lower extremities. Multicomponent ground-reaction forces of both the push-off and landing limbs were measured in six collegiate and one high school level baseball pitchers. Full body kinematics were simultaneously recorded to correlate phases in the pitching cycle with the force data. Pitchers were found to generate shear forces of 0.35 body weight in the direction of the pitch with the push-off leg and to resist forces of 0.72 body weight with the landing leg. Wrist velocity was found to correlate highly with increased leg drive. This study validates the clinical impression that the lower extremity is an important contributor to the throwing motion. Based on this study, strengthening of the lower extremities could be inferred to be important both to enhance performance and to avoid injury.

  6. Large format, small pixel pitch and hot detectors at SOFRADIR

    NASA Astrophysics Data System (ADS)

    Reibel, Y.; Rouvie, A.; Nedelcu, A.; Augey, T.; Pere-Laperne, N.; Rubaldo, L.; Billon-Lanfrey, D.; Gravrand, O.; Rothman, J.; Destefanis, G.

    2013-10-01

    Recently Sofradir joined a very small circle of IR detector manufacturers with expertise every aspect of the cooled and uncooled IR technologies, all under one roof by consolidating all IR technologies available in France. These different technologies are complementary and are used depending of the needs of the applications mainly concerning the detection range needs as well as their ability to detect in bad weather environmental conditions. SNAKE (InGaAs) and SCORPIO LW (MCT) expand Sofradir's line of small pixel pitch TV format IR detectors from the mid-wavelength to the short and long wavelengths. Our dual band MW-LW QWIP detectors (25μm, 384×288 pixels) benefit to tactical platforms giving an all-weather performance and increasing flexibility in the presence of battlefield obscurants. In parallel we have been pursuing further infrared developments on future MWIR detectors, such as the VGA format HOT detector that consumes 2W and the 10μm pitch IR detector which gives us a leading position in innovation. These detectors are designed for long-range surveillance equipment, commander or gunner sights, ground-to-ground missile launchers and other applications that require higher resolution and sensitivity to improve reconnaissance and target identification. This paper discusses the system level performance in each detector type.

  7. Application of the matching law to pitch selection in professional baseball.

    PubMed

    Cox, David J; Sosine, Jacob; Dallery, Jesse

    2017-03-09

    This study applied the generalized matching equation (GME) to pitch selection in professional baseball. The GME was fitted to the relation between pitch selection and hitter outcomes for five professional baseball pitchers during the 2014 Major League Baseball season. The GME described pitch selection well. Pitch allocation varied across different game contexts such as inning, count, and number of outs in a manner consistent with the GME. Finally, within games, bias decreased for four of the five pitchers and the sensitivity parameter increased for three of the five pitchers. The results extend the generality of the GME to multialternative natural sporting contexts, and demonstrate the influence of context on behavior in natural environments.

  8. Localized topological states in Bragg multihelicoidal fibers with combined pitch-jump and twist defects

    NASA Astrophysics Data System (ADS)

    Alexeyev, C. N.; Lapin, B. P.; Yavorsky, M. A.

    2017-04-01

    We have studied the influence of pitch-jump defects on the existence of defect-localized states in multihelicoidal Bragg fibers with twist defects. We have shown that the total electromagnetic field energy stored in the defect-localized topologically charged modes essentially depends on the pitch jump and rapidly tends to zero as this increases. This can be used to make the defect mode radiate the stored energy. We have also shown that by tuning the magnitude of the pitch mismatch one can control the wavelength at which the maximal localization takes place. Such fine tuning of the pitch jump can in principle be achieved by piezoelectric modulation.

  9. Singing ability is rooted in vocal-motor control of pitch.

    PubMed

    Hutchins, Sean; Larrouy-Maestri, Pauline; Peretz, Isabelle

    2014-11-01

    The inability to vocally match a pitch can be caused by poor pitch perception or by poor vocal-motor control. Although previous studies have tried to examine the relationship between pitch perception and vocal production, they have failed to control for the timbre of the target to be matched. In the present study, we compare pitch-matching accuracy with an unfamiliar instrument (the slider) and with the voice, designed such that the slider plays back recordings of the participant's own voice. We also measured pitch accuracy in singing a familiar melody ("Happy Birthday") to assess the relationship between single-pitch-matching tasks and melodic singing. Our results showed that participants (all nonmusicians) were significantly better at matching recordings of their own voices with the slider than with their voice, indicating that vocal-motor control is an important limiting factor on singing ability. We also found significant correlations between the ability to sing a melody in tune and vocal pitch matching, but not pitch matching on the slider. Better melodic singers also tended to have higher quality voices (as measured by acoustic variables). These results provide important evidence about the role of vocal-motor control in poor singing ability and demonstrate that single-pitch-matching tasks can be useful in measuring general singing abilities.

  10. Singing with yourself: evidence for an inverse modeling account of poor-pitch singing.

    PubMed

    Pfordresher, Peter Q; Mantell, James T

    2014-05-01

    Singing is a ubiquitous and culturally significant activity that humans engage in from an early age. Nevertheless, some individuals - termed poor-pitch singers - are unable to match target pitches within a musical semitone while singing. In the experiments reported here, we tested whether poor-pitch singing deficits would be reduced when individuals imitate recordings of themselves as opposed to recordings of other individuals. This prediction was based on the hypothesis that poor-pitch singers have not developed an abstract "inverse model" of the auditory-vocal system and instead must rely on sensorimotor associations that they have experienced directly, which is true for sequences an individual has already produced. In three experiments, participants, both accurate and poor-pitch singers, were better able to imitate sung recordings of themselves than sung recordings of other singers. However, this self-advantage was enhanced for poor-pitch singers. These effects were not a byproduct of self-recognition (Experiment 1), vocal timbre (Experiment 2), or the absolute pitch of target recordings (i.e., the advantage remains when recordings are transposed, Experiment 3). Results support the conceptualization of poor-pitch singing as an imitative deficit resulting from a deficient inverse model of the auditory-vocal system with respect to pitch.

  11. A Pitch Extraction Method with High Frequency Resolution for Singing Evaluation

    NASA Astrophysics Data System (ADS)

    Takeuchi, Hideyo; Hoguro, Masahiro; Umezaki, Taizo

    This paper proposes a pitch estimation method suitable for singing evaluation incorporable in KARAOKE machines. Professional singers and musicians have sharp hearing for music and singing voice. They recognize that singer's voice pitch is “a little off key” or “be in tune”. In the same way, the pitch estimation method that has high frequency resolution is necessary in order to evaluate singing. This paper proposes a pitch estimation method with high frequency resolution utilizing harmonic characteristic of autocorrelation function. The proposed method can estimate a fundamental frequency in the range 50 ∼ 1700[Hz] with resolution less than 3.6 cents in light processing.

  12. Method for producing mesophase-containing pitch by using carrier gas

    SciTech Connect

    Watanabe, M.

    1984-12-11

    A method for producing a mesophase-containing pitch from petroleum pitch or coal tar pitch is disclosed. According to this method volatile distillate fractions, which are harmful to mesophase formation and present originally in the raw material pitch or formed as by-product during heat treatment time are driven off by using a carrier gas at a temperature of 360/sup 0/ to 450/sup 0/ C. in order to shorten the overall heat treatment time and advance the mesophase formation smoothly by the increase of stirring effect.

  13. Impact of pitching rate on yeast fermentation performance and beer flavour.

    PubMed

    Verbelen, P J; Dekoninck, T M L; Saerens, S M G; Van Mulders, S E; Thevelein, J M; Delvaux, F R

    2009-02-01

    The volumetric productivity of the beer fermentation process can be increased by using a higher pitching rate (i.e. higher inoculum size). However, the impact of the pitching rate on crucial fermentation and beer quality parameters has never been assessed systematically. In this study, five pitching rates were applied to lab-scale fermentations to investigate its impact on the yeast physiology and beer quality. The fermentation rate increased significantly and the net yeast growth was lowered with increasing pitching rate, without affecting significantly the viability and the vitality of the yeast population. The build-up of unsaturated fatty acids in the initial phase of the fermentation was repressed when higher yeast concentrations were pitched. The expression levels of the genes HSP104 and HSP12 and the concentration of trehalose were higher with increased pitching rates, suggesting a moderate exposure to stress in case of higher cell concentrations. The influence of pitching rate on aroma compound production was rather limited, with the exception of total diacetyl levels, which strongly increased with the pitching rate. These results demonstrate that most aspects of the yeast physiology and flavour balance are not significantly or negatively affected when the pitching rate is changed. However, further research is needed to fully optimise the conditions for brewing beer with high cell density populations.

  14. CFD simulation of fixed and variable pitch vertical axis tidal turbine

    NASA Astrophysics Data System (ADS)

    Sheng, Qihu; Khalid, Syed Shah; Xiong, Zhimin; Sahib, Ghazala; Zhang, Liang

    2013-06-01

    In this paper, hydrodynamic analysis of vertical axis tidal turbine (both fixed pitch & variable pitch) is numerically analyzed. Two-dimensional numerical modeling & simulation of the unsteady flow through the blades of the turbine is performed using ANSYS CFX, hereafter CFX, which is based on a Reynolds-Averaged Navier-Stokes (RANS) model. A transient simulation is done for fixed pitch and variable pitch vertical axis tidal turbine using a Shear Stress Transport turbulence (SST) scheme. Main hydrodynamic parameters like torque T, combined moment C M , coefficients of performance C P and coefficient of torque C T , etc. are investigated. The modeling and meshing of turbine rotor is performed in ICEM-CFD. Moreover, the difference in meshing schemes between fixed pitch and variable pitch is also mentioned. Mesh motion option is employed for variable pitch turbine. This article is one part of the ongoing research on turbine design and developments. The numerical simulation results are validated with well reputed analytical results performed by Edinburgh Design Ltd. The article concludes with a parametric study of turbine performance, comparison between fixed and variable pitch operation for a four-bladed turbine. It is found that for variable pitch we get maximum C P and peak power at smaller revolution per minute N and tip sped ratio λ.

  15. Voice pitch alters mate-choice-relevant perception in hunter–gatherers

    PubMed Central

    Apicella, Coren L.; Feinberg, David R.

    2008-01-01

    In humans, voice pitch is thought to be a cue of underlying quality and an important criterion for mate choice, but data from non-Western cultures have not been provided. Here we test attributions to and preferences for voices with raised and lowered pitch in hunter–gatherers. Using a forced-choice playback experiment, we found that both men and women viewed lower pitched voices in the opposite sex as being better at acquiring resources (e.g. hunting and gathering). While men preferred higher pitched women's voices as marriage partners, women showed no overall preference for voice pitch in men. However, women who were currently breastfeeding had stronger preferences for higher pitched male voices whereas women not currently breastfeeding preferred lower pitched voices. As testosterone is considered a costly signal associated with dominance, heritable immunity to infection and low paternal investment, women's preferences potentially reflect a trade-off between securing good genes and paternal investment. Men's preferences for higher pitched female voices are probably due to an evolved preference for markers of fecundity, reflected in voice pitch. PMID:19129125

  16. The Effects of Pitch Shifts on Delay-Induced Changes in Vocal Sequencing in a Songbird

    PubMed Central

    Kelly, Conor W.

    2017-01-01

    Abstract Like human speech, vocal behavior in songbirds depends critically on auditory feedback. In both humans and songbirds, vocal skills are acquired by a process of imitation whereby current vocal production is compared to an acoustic target. Similarly, performance in adulthood relies strongly on auditory feedback, and online manipulations of auditory signals can dramatically alter acoustic production even after vocalizations have been well learned. Artificially delaying auditory feedback can disrupt both speech and birdsong, and internal delays in auditory feedback have been hypothesized as a cause of vocal dysfluency in persons who stutter. Furthermore, in both song and speech, online shifts of the pitch (fundamental frequency) of auditory feedback lead to compensatory changes in vocal pitch for small perturbations, but larger pitch shifts produce smaller changes in vocal output. Intriguingly, large pitch shifts can partially restore normal speech in some dysfluent speakers, suggesting that the effects of auditory feedback delays might be ameliorated by online pitch manipulations. Although birdsong provides a promising model system for understanding speech production, the interactions between sensory feedback delays and pitch shifts have not yet been assessed in songbirds. To investigate this, we asked whether the addition of a pitch shift modulates delay-induced changes in Bengalese finch song, hypothesizing that pitch shifts would reduce the effects of feedback delays. Compared with the effects of delays alone, combined delays and pitch shifts resulted in a significant reduction in behavioral changes in one type of sequencing (branch points) but not another (distribution of repeated syllables). PMID:28144622

  17. Relationship between noise, dose, and pitch in cardiac multi-detector row CT.

    PubMed

    Primak, Andrew N; McCollough, Cynthia H; Bruesewitz, Michael R; Zhang, Jie; Fletcher, Joel G

    2006-01-01

    In spiral computed tomography (CT), dose is always inversely proportional to pitch. However, the relationship between noise and pitch (and hence noise and dose) depends on the scanner type (single vs multi-detector row) and reconstruction mode (cardiac vs noncardiac). In single detector row spiral CT, noise is independent of pitch. Conversely, in noncardiac multi-detector row CT, noise depends on pitch because the spiral interpolation algorithm makes use of redundant data from different detector rows to decrease noise for pitch values less than 1 (and increase noise for pitch values > 1). However, in cardiac spiral CT, redundant data cannot be used because such data averaging would degrade the temporal resolution. Therefore, the behavior of noise versus pitch returns to the single detector row paradigm, with noise being independent of pitch. Consequently, since faster rotation times require lower pitch values in cardiac multi-detector row CT, dose is increased without a commensurate decrease in noise. Thus, the use of faster rotation times will improve temporal resolution, not alter noise, and increase dose. For a particular application, the higher dose resulting from faster rotation speeds should be justified by the clinical benefits of the improved temporal resolution.

  18. Optically activated shutter using a photo-tunable short-pitch chiral nematic liquid crystal

    NASA Astrophysics Data System (ADS)

    Morris, S. M.; Qasim, M. M.; Cheng, K. T.; Castles, F.; Ko, D.-H.; Gardiner, D. J.; Nosheen, S.; Wilkinson, T. D.; Coles, H. J.; Burgess, C.; Hill, L.

    2013-09-01

    We report the demonstration of an optically activated shutter based upon a short-pitch chiral nematic liquid crystal (LC) device sandwiched between crossed polarizers. This LC is comprised of photo-active chiral dopants. In the trans-state, the LC appears dark between crossed polarizers due to the very short pitch. As the pitch is extended through exposure to ultraviolet light, the device becomes transmissive reaching a maximum for a particular value of the pitch. As a result, it is possible to switch between the light and dark states by subjecting the device to visible light so as to cause a cis-trans photo-isomerisation.

  19. Individual differences in cortisol stress response predict increases in voice pitch during exam stress.

    PubMed

    Pisanski, Katarzyna; Nowak, Judyta; Sorokowski, Piotr

    2016-09-01

    Despite a long history of empirical research, the potential vocal markers of stress remain unclear. Previous studies examining speech under stress most consistently report an increase in voice pitch (the acoustic correlate of fundamental frequency, F0), however numerous studies have failed to replicate this finding. In the present study we tested the prediction that these inconsistencies are tied to variation in the severity of the stress response, wherein voice changes may be observed predominantly among individuals who show a cortisol stress response (i.e., an increase in free cortisol levels) above a critical threshold. Voice recordings and saliva samples were collected from university psychology students at baseline and again immediately prior to an oral examination. Voice recordings included both read and spontaneous speech, from which we measured mean, minimum, maximum, and the standard deviation in F0. We observed an increase in mean and minimum F0 under stress in both read and spontaneous speech, whereas maximum F0 and its standard deviation showed no systematic changes under stress. Our results confirmed that free cortisol levels increased by an average of 74% (ranging from 0 to 270%) under stress. Critically, increases in cortisol concentrations significantly predicted increases in mean F0 under stress for both speech types, but did not predict variation in F0 at baseline. On average, stress-induced increases in voice pitch occurred only when free cortisol levels more than doubled their baseline concentrations. Our results suggest that researchers examining speech under stress should control for individual differences in the magnitude of the stress response.

  20. Effects of Lower Frequency-to-Electrode Allocations on Speech and Pitch Perception with the Hybrid Short-Electrode Cochlear Implant

    PubMed Central

    Reiss, Lina A.J.; Perreau, Ann E.; Turner, Christopher W.

    2012-01-01

    Because some users of a Hybrid short-electrode cochlear implant (CI) lose their low-frequency residual hearing after receiving the CI, we tested whether increasing the CI speech processor frequency allocation range to include lower frequencies improves speech perception in these individuals. A secondary goal was to see if pitch perception changed after experience with the new CI frequency allocation. Three subjects who had lost all residual hearing in the implanted ear were recruited to use an experimental CI frequency allocation with a lower frequency cutoff than their current clinical frequency allocation. Speech and pitch perception results were collected at multiple time points throughout the study. In general, subjects showed little or no improvement for speech recognition with the experimental allocation when the CI was worn with a hearing aid in the contralateral ear. However, all three subjects showed changes in pitch perception that followed the changes in frequency allocations over time, consistent with previous studies showing that pitch perception changes upon provision of a CI. PMID:22907151