Influence of microphone characteristics on demodulated sound measurement in near field of parametric loudspeaker

2021 ◽  
Author(s):  
Hideyuki Nomura ◽  
Hiroki Sato
Keyword(s):  
Nonlinear Response ◽  
Measurement Accuracy ◽  
Near Field ◽  
High Sensitivity ◽  
Theoretical Predictions ◽  
Acoustic Filters ◽  
Frequency Components ◽  
Sound Measurement ◽  
Low Sensitivity ◽  
Spurious Signals

Abstract This study evaluates the accuracy of demodulated sound measurements using a condenser microphone in the near field of a parametric loudspeaker system. Microphones with different sensitivities placed at incidence angles of 0° and 90° were used to measure demodulation frequency components without special acoustic filters. The measured components were compared with theoretical predictions. The results show that the measured sound pressure using microphones placed at 0° was up to several tens of decibels larger than the theoretical predictions and significantly inaccurate in the near field. This was due to the nonlinear response of the microphone, which had high sensitivity at primary sound frequencies, inducing spurious signals. This result suggests that using a microphone with low sensitivity at primary sound frequencies placed at an appropriate angle that reduces sensitivity improves parametric sound measurement accuracy.

scholarly journals Second harmonic generation correlation spectroscopy for characterizing translationally diffusing protein nanocrystals

2016 ◽  
Vol 72 (7) ◽  
pp. 849-859
Author(s):  
Ximeng Y. Dow ◽  
Christopher M. Dettmar ◽  
Emma L. DeWalt ◽  
Justin A. Newman ◽  
Alexander R. Dow ◽  
...  
Keyword(s):  
Second Harmonic Generation ◽  
Harmonic Generation ◽  
Unit Volume ◽  
Second Harmonic ◽  
Incident Beam ◽  
High Sensitivity ◽  
Correlation Spectroscopy ◽  
Optical Process ◽  
Active Nanoparticles ◽  
Low Sensitivity

Second harmonic generation correlation spectroscopy (SHG-CS) is demonstrated as a new approach to protein nanocrystal characterization. A novel line-scanning approach was performed to enable autocorrelation analysis without sample damage from the intense incident beam. An analytical model for autocorrelation was developed, which includes a correction for the optical scattering forces arising when focusing intense, infrared beams. SHG-CS was applied to the analysis of BaTiO3nanoparticles ranging from 200 to ∼500 nm and of photosystem I nanocrystals. A size distribution was recovered for each sample and compared with the size histogram measured by scanning electron microscopy (SEM). Good agreement was observed between the two independent measurements. The intrinsic selectivity of the second-order nonlinear optical process provides SHG-CS with the ability to distinguish well ordered nanocrystals from conglomerates and amorphous aggregates. Combining the recovered distribution of particle diameters with the histogram of measured SHG intensities provides the inherent hyperpolarizability per unit volume of the SHG-active nanoparticles. Simulations suggest that the SHG activity per unit volume is likely to exhibit relatively low sensitivity to the subtle distortions within the lattice that contribute to resolution loss in X-ray diffraction, but high sensitivity to the presence of multi-domain crystals.

Fabrication and characteristics of the high-sensitivity humidity sensor of anodic aluminum oxide based on silicon substrates

2018 ◽  
Vol 32 (16) ◽  
pp. 1850199 ◽  
Author(s):  
Degao Lan ◽  
Xiaofeng Zhao ◽  
Fei Wang ◽  
Chunpeng Ai ◽  
Dianzhong Wen ◽  
...  
Keyword(s):  
Aluminum Oxide ◽  
Silicon Substrate ◽  
Anodic Aluminum Oxide ◽  
Nonlinear Response ◽  
Humidity Sensor ◽  
High Sensitivity ◽  
Silicon Substrates ◽  
High Porosity ◽  
Interdigitated Electrodes ◽  
Anodic Aluminum

The humidity sensor based on silicon substrate is presented in this paper, which consists of anodic aluminum oxide (AAO) film and interdigitated electrodes. By using electro-chemical oxidizing technique, AAO film with high porosity is fabricated on the silicon substrate. Under optimal oxidization condition, pore diameter of 37–79 nm and depth about [Formula: see text]m is achieved. Interdigitated electrodes are fabricated on the top of AAO film by vacuum evaporation deposition method. The results show that the sensor has different nonlinear response in whole range of relative humidity (RH). Moreover, it has almost linear relationship between the capacitance and RH at high RH from 75% to 95%. The highest sensitivity is obtained 613 pF/%RH at 1 kHz, which is much higher than other frequencies.

Influence of Irrational Beliefs and Sensitivity to a Person on Future Psychology Students’ Propensity to Coercion or Nonviolence

2021 ◽  
pp. 143-165
Author(s):  
V.G. Maralov ◽  
◽  
V.A. Sitarov ◽  
Keyword(s):  
Irrational Beliefs ◽  
High Sensitivity ◽  
Daily Practice ◽  
Psychology Students ◽  
State Universities ◽  
Low Level ◽  
Level Of Understanding ◽  
Low Sensitivity ◽  
High Level ◽  
Dependent Type

The relevance of the problem is due to the importance of identifying factors that determine the propensity of students to coercion or nonviolence, creating psychological and pedagogical conditions for the formation of the socionomic sphere of nonviolent competencies for future specialists at universities. The theoretical basis of the study was the position of nonviolence as a daily practice of interaction, by which we understand the ability of a person to choose from a number of possible alternatives that carry the least charge of coercion. The aim of the work was to study the influence of irrational beliefs and sensitivity to a person (interest, empathy, understanding and assistance) on the students’ tendency to coercion, manipulation, non-violence and non-interference in the processes of interaction with people. The hypothesis was tested that the tendency of students to coercion, manipulation, and noninterference will be due to expressed irrational beliefs and low level of sensitivity to a person and the tendency to non-violence will be explained by the absence of irrational beliefs and a high level of sensitivity to a person. The study involved 125 students of pedagogical and psychological faculties of the Moscow Humanitarian and Cherepovets State universities. The authors used questionnaires to identify the positions of interaction among students and sensitivity to a person, as well as a list of irrational beliefs proposed by A. Beck and A. Freeman. It is established that the tendency to both coercion and manipulation are determined by the beliefs of anti-social type and low sensitivity to the person. The tendency to manipulate the narcissistic beliefs, high interest in people and understanding them, at the same time the tendency to non-violence and non-interference are determined by beliefs of avoidant and dependent types with a low level of understanding people. And a tendency to non-interference is determined by beliefs of dependent type with unexpressed orientation on helping. The tendency to nonviolence is determined by the high sensitivity to a person and the absence of irrational beliefs of antisocial, passive-aggressive and narcissistic types. As a result, the conclusion is made about the need to form purposefully the ability to nonviolent interaction among students, which should include the work on awareness and overcoming irrational beliefs and the development of sensitivity to a person. The obtained results can be used in practical work with students on the formation of their nonviolent competencies.

scholarly journals Исследование коэффициента диффузии в тонких изделиях из пористых материалов

2019 ◽  
Vol 89 (10) ◽  
pp. 1630
Author(s):  
В.П. Беляев ◽  
С.В. Мищенко ◽  
П.С. Беляев
Keyword(s):  
Mass Transfer ◽  
Porous Media ◽  
Diffusion Coefficient ◽  
Transfer Process ◽  
Noise Immunity ◽  
Measurement Accuracy ◽  
High Sensitivity ◽  
Mass Transfer Process ◽  
Static Characteristic ◽  
Rapid Diffusion

A new method for studying mass transfer process in porous media has been considered, which allows the rapid diffusion coefficient control in thin products without destroying them and without the preliminary calibration of the diffuser concentration meter. The method provides an increase in the measurement accuracy due to the possibility of choosing the measured parameters included in the design expression. Parameters are taking from the segments of converter static characteristic. The converter has high sensitivity and noise immunity.

scholarly journals Predicting Response to Total Neoadjuvant Treatment (TNT) in Locally Advanced Rectal Cancer Based on Multiparametric Magnetic Resonance Imaging: A Retrospective Study

2020 ◽  
Author(s):  
Ganlu Ouyang ◽  
Xibiao Yang ◽  
Xiangbing Deng ◽  
Wenjian Meng ◽  
Yongyang Yu ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Rectal Cancer ◽  
Lymph Node ◽  
Locally Advanced ◽  
Neoadjuvant Treatment ◽  
High Sensitivity ◽  
Advanced Rectal Cancer ◽  
Locally Advanced Rectal Cancer ◽  
Resonance Imaging ◽  
Low Sensitivity

Abstract Purpose: To investigate the potential value of magnetic resonance imaging (MRI) in predicting response relevance to total neoadjuvant treatment (TNT) in locally advanced rectal cancer.Methods: We analyzed MRI of 71 patients underwent TNT from 2015 to 2017 retrospectively. We categorized the response of TNT as CR (complete response) and non-CR, and high, moderate and low sensitivity. Logistic regression analysis was used to identify the best predictors of response. Diagnostic performance was assessed using receiver - operating characteristic curve analysis.Results: Post–ICT (induction chemotherapy) ∆TL (tumor length), post-CRT (concurrent chemoradiotherapy) ∆LNN (the numbers of lymph node metastases), post–CCT (consolidation chemotherapy) ∆SDWI (maximum cross-sectional area of tumor on diffusion-weighted imaging), post-CCT ADCT (the mean apparent diffusion coefficient values of tumor) and post-CCT ∆LNV (volume of lymph node) were the best CR predictors. Post-CRT EMVI (extramural vascular invasion) and post-CCT ∆ST2 (S on T2-weight) were the best significant factors for high sensitivity. Conclusions: Post-ICT ∆TL and post-CRT EMVI may an early predictor of CR and high sensitivity to TNT, respectively. The grouping scheme of CR and non–CR was more suitable for predicting response by MRI parameters than high, moderate and low sensitivity.Trial registration: retrospectively registered

scholarly journals The Effect of Oral Tactile Sensitivity on Texture Perception and Mastication Behavior in Humans

2018 ◽  
Author(s):  
Grace E. Shupe ◽  
Arran Wilson ◽  
Curtis R. Luckett
Keyword(s):  
High Sensitivity ◽  
Tactile Feedback ◽  
Interindividual Variation ◽  
Texture Perception ◽  
Tactile Acuity ◽  
Force Sensitivity ◽  
Significant Difference ◽  
Low Sensitivity ◽  
Oral Sensitivity ◽  
The Brain

AbstractMastication behavior is a notable source of interindividual variation in texture perception and could be linked to oral sensitivity. As oral sensitivity declines so does the amount of tactile feedback relayed to the brain, resulting in less effective manipulation or food and a reduced ability to discriminate differences. To address these hypotheses, we measured masticatory behavior and related this to texture discrimination and oral sensitivity. The study was performed on 41 participants in two groups, with high (n = 20) or low (n=21) sensitivity. Oral sensitivity was measured using a battery of tests that included: oral stereognosis, lingual tactile acuity, and bite force sensitivity. Sensitivity to texture changes was measured using a series of triangle tests with confectionaries of different hardness, with masticatory patterns and behaviors being video recorded and analyzed using jaw tracking software. Overall, there was no significant difference between high and low sensitivity participants and their ability to distinguish texture changes. But, there were significantly different trends found between the groups based on their masticatory behaviors including chewing pattern and overall number of chews. But, it was found that multiple masticatory behaviors were being modulated by oral sensitivity, including overall chewing cycles used (p < 0.0001). More, specifically those in the high sensitivity group used more stochastic chewing movements, while those in the low sensitivity group were found to use crescent-shaped chewing cycles. It was also noted that in the high sensitivity group the jaw moved further distances (p < 0.0001) in all phases and moved at a higher velocity when opening (p < 0.0001) but not when closing, when compared to the low sensitivity group. These results help bolster evidence that mastication and oral sensitivity are related.

Developing a simplified method for analysis and design of isolated structures with the novel quintuple friction pendulum system under bidirectional near-field excitations

2021 ◽  
pp. 107754632110482
Author(s):  
Hamed Keikha ◽  
Gholamreza Ghodrati Amiri
Keyword(s):  
Nonlinear Response ◽  
Near Field ◽  
Lateral Force ◽  
History Analysis ◽  
Special Cases ◽  
Simplified Method ◽  
Response History Analysis ◽  
Nonlinear Response History Analysis ◽  
Isolated Structures ◽  
Friction Pendulum

Simplified analysis methods for seismically isolated structures proposed in recent structural codes and specifications are frequently used to reduce the computational effort and to simplify the design procedure, either directly for special cases or for checking the results of nonlinear response history analysis. Of the approximate methods, the equivalent lateral force procedure using the effective stiffness and effective damping is one of the best known. In this study, the simplified method is developed by combining the equivalent lateral force procedure with the capacity spectrum method and evaluated in terms of maximum isolator displacements and base shears for isolated structures with recently invented quintuple friction pendulum isolators , with different geometrical and frictional properties, under two different response spectra with corresponding two different sets of bidirectional near-field ground motions for stiff and soft soils site classes. In order to assess the accuracy of the simplified method, the delivered results of the ELF procedure are compared to those of nonlinear response history analysis, by modelling the quintuple friction pendulum isolator 3D element in OpenSees. Eventually, comments on the accuracy of the simplified method are given to make its applications more appropriate in practical design of base isolation systems.

High Sensitivity Electrical Properties Measurement of Graphene-based Composites using Interferometric Near-field Microwave Technique

2021 ◽  
Author(s):  
HIND BAKLI ◽  
Mohamed MOUALHI ◽  
Mourad Makhlouf
Keyword(s):  
Composite Material ◽  
Composite Materials ◽  
Electrical Properties ◽  
Near Field ◽  
High Sensitivity ◽  
Calibration Model ◽  
Electrical Model ◽  
Microwave Technique ◽  
Lumped Elements ◽  
Local Properties

Abstract High sensitivity electrical properties measurement of composite materials using an interferometric near-field microwave technique is proposed in this paper. A one-port calibration model is developed to relate the measured transmission coefficient to the local properties of the material. To represent the probe-composite sample interaction, an electrical model based on lumped elements is developed. As a demonstration, complex permittivity and conductivity of composite materials prepared with polyvinyl chloride (PVC) and different concentration of graphene are experimentally determined at 2.45 GHz. The obtained results show that the proposed technique is sensitive for the detection of small contrast of permittivity and conductivity in composite material. When graphene concentration increases from 1 to 30%, the conductivity increases from 0.0061 s/m to 0.056 s/m.

scholarly journals Radar Detection of Individual Raindrops

2019 ◽  
Vol 100 (12) ◽  
pp. 2433-2450 ◽  
Author(s):  
Jerome M. Schmidt ◽  
Piotr J. Flatau ◽  
Paul R. Harasti ◽  
Robert. D. Yates ◽  
David J. Delene ◽  
...  
Keyword(s):  
Doppler Radar ◽  
Near Field ◽  
High Sensitivity ◽  
Radar Reflectivity ◽  
Range Resolution ◽  
Particle Properties ◽  
Drop Dynamics ◽  
Cloud Radar ◽  
Aircraft Tracking ◽  
Oscillation Characteristics

Abstract Descriptions of the experimental design and research highlights obtained from a series of four multiagency field projects held near Cape Canaveral, Florida, are presented. The experiments featured a 3 MW, dual-polarization, C-band Doppler radar that serves in a dual capacity as both a precipitation and cloud radar. This duality stems from a combination of the radar’s high sensitivity and extremely small-resolution volumes produced by the narrow 0.22° beamwidth and the 0.543 m along-range resolution. Experimental highlights focus on the radar’s real-time aircraft tracking capability as well as the finescale reflectivity and eddy structure of a thin nonprecipitating stratus layer. Examples of precipitating storm systems focus on the analysis of the distinctive and nearly linear radar reflectivity signatures (referred to as “streaks”) that are caused as individual hydrometeors traverse the narrow radar beam. Each streak leaves a unique radar reflectivity signature that is analyzed with regard to estimating the underlying particle properties such as size, fall speed, and oscillation characteristics. The observed along-streak reflectivity oscillations are complex and discussed in terms of diameter-dependent drop dynamics (oscillation frequency and viscous damping time scales) as well as radar-dependent factors governing the near-field Fresnel radiation pattern and inferred drop–drop interference.

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