Hand to mouth: automatic imitation across effector systems

The effector-specificity of automatic imitation was investigated using a stimulus-response compatibility (SRC) procedure in which participants were required to make an open or a close response with either their hand or their mouth. The correct response for each trial was indicated by a pair of letters, and each of these imperative stimuli was accompanied by task-irrelevant action images depicting a hand or mouth opening or closing. Relative to the response, the irrelevant stimulus was either movement compatible or movement incompatible, and either effector compatible or effector incompatible. A movement compatibility effect was observed for both hand and mouth responses. These movement compatibility effects were present when the irrelevant stimulus was effector compatible and when it was effector incompatible, but they were smaller when the irrelevant stimulus and response effectors were incompatible. These findings, which are consistent with the associative sequence learning model of imitation, indicate that automatic imitation is partially effector-specific, and therefore that the effector specificity of intentional and instructed imitation reflects, at least in part, the nature of the mechanisms that mediate visuomotor translation for imitation

Accurate measurement of the piezoelectric coefficient of thin films by eliminating the substrate bending effect using spatial scanning laser vibrometry

One of the major difficulties in measuring the piezoelectric coefficient d(33,f) for thin films is the elimination of the contribution from substrate bending. We show by theoretical analysis and experimental measurements that by bonding thin film piezoelectric samples to a substantial holder, the substrate bending can be minimized to a negligible level. Once the substrate bending can be effectively eliminated, single-beam laser scanning vibrometry can be used to measure the precise strain distribution of a piezoelectric thin film under converse actuation. A significant strain increase toward the inside edge of the top electrode (assuming a fully covered bottom electrode) and a corresponding strain peak in the opposite direction just outside the electrode edge were observed. These peaks were found to increase with the increasing Poisson's ratio and transverse piezoelectric coefficient of the piezoelectric thin film. This is due to the non-continuity of the electric field at the edge of the top electrode, which leads to the concentration of shear stress and electric field in the vicinity of the electrode edge. The measured d(33,f) was found to depend not only on the material properties such as the electromechanical coefficients of the piezoelectric thin films and elastic coefficients of the thin film and the substrate, but also on the geometry factors such as the thickness of the piezoelectric films, the dimensions of the electrode, and also the thickness of the substrate

Social attitudes modulate automatic imitation

In naturalistic interpersonal settings, mimicry or ‘automatic imitation’ generates liking, affiliation, cooperation and other positive social attitudes. The purpose of this study was to find out whether the relationship between social attitudes and mimicry is bidirectional: Do social attitudes have a direct and specific effect on mimicry? Participants were primed with pro-social, neutral or anti-social words in a scrambled sentence task. They were then tested for mimicry using a stimulus-response compatibility procedure. In this procedure, participants were required to perform a pre-specified movement (e.g. opening their hand) on presentation of a compatible (open) or incompatible (close) hand movement. Reaction time data were collected using electromyography (EMG) and the magnitude of the mimicry / automatic imitation effect was calculated by subtracting reaction times on compatible trials from those on incompatible trials. Pro-social priming produced a larger automatic imitation effect than anti-social priming, indicating that the relationship between mimicry and social attitudes is bidirectional, and that social attitudes have a direct and specific effect on the tendency to imitate behavior without intention or conscious awareness

Low-profile and wearable energy harvester based on plucked piezoelectric cantilevers

The Pizzicato Energy Harvester (EH) introduced the technique of frequency up-conversion to piezoelectric EHs wearable on the lateral side of the knee-joint. The operation principle is to pluck the piezoelectric bimorphs with plectra so that they produce electrical energy during the ensuing mechanical vibrations. The device presented in this work is, in some ways, an evolution of the earlier Pizzicato: it is a significantly more compact and lighter device; the central hub holds 16 piezoelectric bimorphs shaped as trapezoids, which permits a sleek design and potentially increased energy output for the same bimorph area. Plectra were formed by Photochemical Machining of a 100-μm-thick steel sheet. To avoid the risk of short-circuiting, the plectra were electrically passivated by sputtering a 100 nm layer of ZrO2. Bench tests with the steel plectra showed a very large energy generation. Polyimide plectra were also manufactured with a cutting plotter from a 125μm-thick film. Besides bench tests, a volunteer wore the device while walking on flat ground or climbing stairs, with a measured energy output of approximately 0.8 mJ per step. Whereas most of the tests were performed by the traditional method of discharging the rectified output from the EH onto a resistive load, tests were performed also with a circuit offering a stabilised 3.3 V supply. The circuit produced a stable 0.1 mA supply during running gait with kapton plectra

An Investigative Study Into Student Motivation and Identity Among Upper Class Electrical and Computer Engineering Students

This study investigates upper-class electrical and computer engineering students’ motivation and how students identify with their major. In addition, it also explores how student chosen research, projects, and learning impact the levels of motivation in students and how students identify with their major. Three different surveys were used over the course of the spring semester of 2017 at the University of Maine for this study: the Pittsburgh Freshman Engineering Aptitude Survey, the Project Ownership Survey, and the 2017 Electrical and Computer Engineering Survey. Participants for this study were junior and senior electrical and computer engineers, and students enrolled in ECE 466: Sensor Technology and Information. This study found that students exposed to research prior to the selection of a project, experienced increased levels of ownership and motivation for projects. Secondly, this study found that students experienced lower levels of motivation near the end of the semester when compared to the beginning

Development of an Electrical Interface for A Lateral Field Excited Sensor System

Sensor systems are utilized to provide critical information to an end user which may range from a physician in a heath care facility to a soldier in a battle field environment. The heart of the sensor system is the sensing platform, examples of which include semiconductor, piezoelectric and optical devices. The responses of these sensors must be converted into a format that the user can read and interpret. This conversion is achieved through integrating the sensing platform with an electrical interface. The focus of this thesis is the development of the first electrical interface for Quartz Crystal Microbalance (QCM) sensors in the Lateral Field Excitation (LFE) configuration. Common techniques used for interfacing with thickness field excitation (TFE) QCM devices include impedance-based systems, oscillator systems, and phase-mass based systems. Although oscillators have been successfully designed for TFE QCMs, attempts to develop an oscillator-based interface system for the LFE QCMs operating in air and vacuum media have been unsuccessful. A comparative study of LFE and TFE sensors operating in air and vacuum media was conducted to determine the reason why these interfaces do not work with LFE QCMs. It was concluded that compared to TFE sensors LFE sensors have higher motional resistance, Rm, and narrower separation between the series and parallel resonant frequencies, which inhibited oscillation. To identify an optimum configuration for the 6MHz LFE sensor based on the sensor\u27s impedance response, 45 different configurations for the LFE sensor were fabricated and tested. Based on the conclusions of the comparative study and further investigation into QCM electrical interfaces, two electrical interface systems were investigated for the chosen LFE: the Balanced Bridge Oscillator (BBO) and the Phase Shift Monitoring system. The BBO, a type of frequency tracking system, was selected as the parallel capacitance seen by the sensor can be compensated for, improving the bandwidth of the sensors impedance response. This circuit can be tuned to match the LFE response, and incorporate automatic gain control. However, The fabricated BBO was unable to achieve a stable oscillation with current LFE devices. The Phase-Shift Monitoring system, which is based on the Phase-Mass characterization method, utilizes an external signal to excite the sensor, and the change in the phase shift of the sensor is tracked as a load is applied to it. The system outputs two DC signals corresponding to the detected change in phase-shift and signal amplitude. The Phase-Mass Monitoring system was tested using both liquid and solid loading with the LFE sensor, and was able to consistently detect masses in the 10s of micrograms range. When the LFE was loaded with 52μg in air, the system output 7.45mV with a tolerance of ±0.6mV. The Phase-Shift Monitoring system is the first electrical interface to be successfully integrated with the LFE sensor platform in air and vacuum media, where oscillator-based systems have been unsuccessful. Further work and testing on the system are required to fully characterize the phase-mass relationship of the LFE, as well as developing the system for commercialization

Rural settlement and population in England between 1676 and 1851: an experiment in historical geography

Any observant traveller will see within Britain contrasts in rural settlement, with some landscapes dominated by villages and others by single farmsteads. Such contrasts were observed by topographers as early as the Elizabethan period and are deep rooted. This study examines on a very broad scale, in part national, in part local regional, the linkages between settlement and population. To complicate matters, population is examined at three dates, 1676, 1801 and 1851. This demands that the analyses consider correlations between the real levels of population, the spatial patterns within these distributions, the dynamics of change and the evolving landscape of settlement. Both synthesis and analysis are involved: the synthesis of work by other scholars to generate a national view in the first part of the study, and in the second part, the analysis of several local regional contexts. The conclusions are summarised in a model, highlighting the broad through time links between settlement and population

An investigation of children\u27s ideas about conservation of energy within a concept-based model.

Significant improvement in American science education is desirable from many perspectives. This need can be encapsulated in the student learning goal of flexible, inquiry-based problem solving. To guide efforts to move towards this goal, an Amalgamated Model of science education is synthesized from six major trends in science education. Explication of this model is focused on the physical sciences, as is the research carried out to test one of the predictions of the Model. One keystone of the Amalgamated Model is the delineation and characterization of concepts according to the three properties of generality, complexity, and abstractness. Using these three properties, a conceptual structure for physical science is constructed. When this structure is compared with conventional physical science curricula, a large discrepancy is in the treatment of the conservation of energy concept. The Model predicts that elementary and middle school age children develop intuitive understandings of the concept, whereas conventionally it is believed to be inherently difficult and comprehensible only to older, high school students. To test this prediction, two sets of tasks and associated clinical interviews are administered to 48 subjects randomly drawn from a K-6 population. The first set of tasks consists of the classical Piagetian conservation instances and the second set investigates understanding of conservation of energy. The quantitative data generated by the two tasks is analyzed to measure the degree of connection within subjects\u27 conceptual structures between their ability to conserve quantity, substance, weight and volume and their ability to conserve energy. The results indicated that understanding of conservation of energy is connected to and apparently develops from the understandings of Piagetian conservation. The experimental and analytical methodologies could be used for further mapping of conceptual structures. It would seem that the prediction of the Amalgamated Model cannot be rejected as false, providing some justification for using the Model as a future framework for research in conceptual structures and for science curriculum development