scholarly journals Resonators in insect sound production: how insects produce loud pure-tone songs

1999 ◽  
Vol 202 (23) ◽  
pp. 3347-3357 ◽  
Author(s):  
H.C. Bennet-Clark
Keyword(s):  
Pure Tone ◽  
Sound Production ◽  
Slow Muscle ◽  
Frequency Multiplier ◽  
Contraction Rate ◽  
Mechanical Resonator ◽  
Second Stage ◽  
Different Types ◽  
Song Frequency ◽  
Slow Contraction

In a resonant vibration, two reactive elements, such as a mass and a spring, interact: the resonant frequency depends on the magnitude of these two elements. The build-up and decay of the vibration depend on the way the resonator is driven and on the damping in the system. The evidence for the existence of resonators in insect sound production is assessed. The mechanics of different types of sound-producing system found in insects is described. Mechanical frequency-multiplier mechanisms, which convert the relatively slow contraction of muscles to the higher frequency of the sound, are commonly used to convert the comparatively slow muscle contraction rate to the higher frequency of the sound. The phasing and rate of mechanical excitation may also affect the frequency and duration of the sound that is produced. Although in many insects the song may appear to be produced by the excitation of a simple resonator, the song frequency may not be constant, suggesting that other factors, such as the mechanism of excitation, or variation of the effective mass or elasticity of the system during sound production, may be additional determinants of the song frequency. Loud, and hence efficient, transduction of the energy of a mechanical resonator into sound may involve a second stage of transduction which, by damping the resonator, may compromise tonal purity. Some insect singers resolve this problem by tuning both stages of transduction to the same frequency, thereby maintaining tonal purity.

Dynamics of Cricket Sound Production

2015 ◽  
Vol 137 (4) ◽  
Author(s):  
Vamsy Godthi ◽  
Rudra Pratap
Keyword(s):  
Natural Frequency ◽  
Sound Production ◽  
Microelectromechanical Systems ◽  
Beat Frequency ◽  
Impulsive Loading ◽  
Frequency Multiplier ◽  
Fe Model ◽  
Song Frequency ◽  
Cricket Song ◽  
Impulse Train

The clever designs of natural transducers are a great source of inspiration for man-made systems. At small length scales, there are many transducers in nature that we are now beginning to understand and learn from. Here, we present an example of such a transducer that is used by field crickets to produce their characteristic song. This transducer uses two distinct components—a file of discrete teeth and a plectrum that engages intermittently to produce a series of impulses forming the loading, and an approximately triangular membrane, called the harp, that acts as a resonator and vibrates in response to the impulse-train loading. The file-and-plectrum act as a frequency multiplier taking the low wing beat frequency as the input and converting it into an impulse-train of sufficiently high frequency close to the resonant frequency of the harp. The forced vibration response results in beats producing the characteristic sound of the cricket song. With careful measurements of the harp geometry and experimental measurements of its mechanical properties (Young's modulus determined from nanoindentation tests), we construct a finite element (FE) model of the harp and carry out modal analysis to determine its natural frequency. We fine tune the model with appropriate elastic boundary conditions to match the natural frequency of the harp of a particular species—Gryllus bimaculatus. We model impulsive loading based on a loading scheme reported in literature and predict the transient response of the harp. We show that the harp indeed produces beats and its frequency content matches closely that of the recorded song. Subsequently, we use our FE model to show that the natural design is quite robust to perturbations in the file. The characteristic song frequency produced is unaffected by variations in the spacing of file-teeth and even by larger gaps. Based on the understanding of how this natural transducer works, one can design and fabricate efficient microscale acoustic devices such as microelectromechanical systems (MEMS) loudspeakers.

An Enhanced Two Stage MMSE Equalizer for Coded FBMC/OQAM Systems

2019 ◽  
Vol 10 (1) ◽  
pp. 69-82 ◽  
Author(s):  
Mohammad Rizk Assaf ◽  
Abdel-Nasser Assimi
Keyword(s):  
Error Propagation ◽  
Channel Model ◽  
Error Correcting Codes ◽  
Two Stage ◽  
Probability Of Error ◽  
Second Stage ◽  
Different Types ◽  
Mmse Equalizer ◽  
And Performance ◽  
Ici Cancellation

In this article, the authors investigate the enhanced two stage MMSE (TS-MMSE) equalizer in bit-interleaved coded FBMC/OQAM system which gives a tradeoff between complexity and performance, since error correcting codes limits error propagation, so this allows the equalizer to remove not only ICI but also ISI in the second stage. The proposed equalizer has shown less design complexity compared to the other MMSE equalizers. The obtained results show that the probability of error is improved where SNR gain reaches 2 dB measured at BER compared with ICI cancellation for different types of modulation schemes and ITU Vehicular B channel model. Some simulation results are provided to illustrate the effectiveness of the proposed equalizer.

A novel two-stage method of plant seedlings classification based on deep learning

2021 ◽  
pp. 1-11
Author(s):  
Tianhong Dai ◽  
Shijie Cong ◽  
Jianping Huang ◽  
Yanwen Zhang ◽  
Xinwang Huang ◽  
...  
Keyword(s):  
Deep Learning ◽  
Learning Technology ◽  
Two Stage ◽  
Second Stage ◽  
Stage Classification ◽  
Different Types ◽  
Two Stages ◽  
Plant Seedlings

In agricultural production, weed removal is an important part of crop cultivation, but inevitably, other plants compete with crops for nutrients. Only by identifying and removing weeds can the quality of the harvest be guaranteed. Therefore, the distinction between weeds and crops is particularly important. Recently, deep learning technology has also been applied to the field of botany, and achieved good results. Convolutional neural networks are widely used in deep learning because of their excellent classification effects. The purpose of this article is to find a new method of plant seedling classification. This method includes two stages: image segmentation and image classification. The first stage is to use the improved U-Net to segment the dataset, and the second stage is to use six classification networks to classify the seedlings of the segmented dataset. The dataset used for the experiment contained 12 different types of plants, namely, 3 crops and 9 weeds. The model was evaluated by the multi-class statistical analysis of accuracy, recall, precision, and F1-score. The results show that the two-stage classification method combining the improved U-Net segmentation network and the classification network was more conducive to the classification of plant seedlings, and the classification accuracy reaches 97.7%.

Ontology Engineering for Gastric Dystemperament in Persian Medicine

2021 ◽  
Author(s):  
Hassan Shojaee-Mend ◽  
Haleh Ayatollahi ◽  
Azam Abdolahadi
Keyword(s):  
Literature Review ◽  
Delphi Study ◽  
Evaluation Study ◽  
Mixed Methods Study ◽  
Case Based Reasoning ◽  
Second Stage ◽  
New Concepts ◽  
Persian Medicine ◽  
Different Types ◽  
Specification Document

Abstract Objective Developing an ontology can help collecting and sharing information in traditional medicine including Persian medicine in a well-defined format. The present study aimed to develop an ontology for gastric dystemperament in the Persian medicine. Methods This was a mixed-methods study conducted in 2019. The first stage was related to providing an ontology requirements specification document. In the second stage, important terms, concepts, and their relationships were identified via literature review and expert panels. Then, the results derived from the second stage were refined and validated using the Delphi method in three rounds. Finally, in the fourth stage, the ontology was evaluated in terms of consistency and coherence. Results In this study, 241 concepts related to different types of gastric dystemperament, diagnostic criteria, and treatments in the Persian medicine were identified through literature review and expert panels, and 12 new concepts were suggested during the Delphi study. In total, after performing three rounds of the Delphi study, 233 concepts were identified. Finally, an ontology was developed with 71 classes, and the results of the evaluation study revealed that the ontology was consistent and coherent. Conclusion In this study, an ontology was created for gastric dystemperament in the Persian medicine. This ontology can be used for designing future systems, such as case-based reasoning and expert systems. Moreover, the use of other evaluation methods is suggested to construct a more complete and precise ontology.

Acoustics of Sound Production and of Hearing in the Bladder Cicada Cystosoma Saundersii (Westwood)

1978 ◽  
Vol 72 (1) ◽  
pp. 43-55 ◽  
Author(s):  
N.H. FLETCHER ◽  
K. G. HILL
Keyword(s):  
Sound Production ◽  
Abdominal Cavity ◽  
Low Frequency ◽  
Sound Intensity ◽  
Electrical Network ◽  
Directional Hearing ◽  
Hearing Sensitivity ◽  
Physical Mechanisms ◽  
Radiated Sound ◽  
Song Frequency

The male cicada of the species Cystosoma saundersii has a grossly enlarged, hollow abdomen and emits a loud calling song with a fundamental frequency of about 800 Hz. At the song frequency, its hearing is nondirectional. The female of C. saundersii lacks sound producing organs, has no enlargement of the abdomen, but possesses an abdominal air sac and has well developed directional hearing at the frequency of the species' song. Physical mechanisms are proposed that explain these observations in semi-quantitative detail using the standard method of electrical network analogues. The abdomen in the male, with its enclosed air, is found to act as a system resonant at the song frequency, thus contributing a large gain in radiated sound intensity. Coupling between this resonator and the auditory tympana accounts for the observed hearing sensitivity in the male, but destroys directionality. In the female, the abdominal cavity acts in association with the two auditory tympana as part of a phase shift network which results in appreciable directionality of hearing at the unusually low frequency of the male song.

scholarly journals CHARACTERISTICS OF FISH CRACKERS BASED ON TYPES OF FISH AND DIFFERENT TYPES OF STARCH

2018 ◽  
Vol 5 (2) ◽  
pp. 102
Author(s):  
Dede Zaenal Arif
Keyword(s):  
Economic Value ◽  
Free Variable ◽  
Physical Analysis ◽  
Second Stage ◽  
Sample Composition ◽  
Different Types ◽  
Development Levels ◽  
Tapioca Flour ◽  
Two Stages ◽  
Organoleptic Parameters

The purpose of this research is to produce fish crackers from different types of fish, namely catfish and patin fish as well as different types of starch and know the characteristics of a good fish crackers. The benefit that can be expected from this research was to utilize catfish and patin fish abundant potency and add economic value. The method of this research was divided into two stages, namely the first stage is the stage which determines the range of the comparison with the fish flour, determine the type of fish and determine the type of flour used by using the hedonik method of organoleptic parameters. On the second stage has a purpose and that is to analyze chemical and physical fish crackers by comparison. The data were analyzed using the method of experiment results simple linear variable (x) increase in comparison of fish and flour (part). The free variable (y) consists of the response of the color, flavor, aroma, texture, volume and the development levels of crispness. The type of fish and the type of starch correlated against all response organoleptic, except the catfish and tapioca flour was not correlated against sense, catfish and cornmeal were not correlated against the texture of the fish, and catfish and sago flour not correlated against scent. The highest correlation is indicated by the sample composition of the cornmeal and catfish fish total value index by 17 of the total value of the correlation coefficient in classification. The sample was selected based on organoleptic level consumer favorite is with the composition of samples catfish and tapioca flour with a 1:1 comparison (111). Based on the results of the chemical analysis of protein obtained 24,38%, fat content of 1.6%, levels of starch of 44.69% and water content of 5.5%. Physical analysis of the parameter and the mobilising of the volume development of IE of 146.43% and the level of crispness that is of 0.56 mm/s/50gram.  

The Mechanics of Stridulation in Bush Crickets (Tettigonioidea, Orthoptera)

1970 ◽  
Vol 52 (3) ◽  
pp. 495-505 ◽  
Author(s):  
W. J. BAILEY
Keyword(s):  
Detailed Analysis ◽  
Pure Tone ◽  
Sound Production ◽  
Sound Radiation ◽  
Rotational Axis ◽  
The Right ◽  
Bush Crickets

1. A method has been devised by which the isolated tegmina of bush crickets can be actuated in such a manner as to simulate the insect's natural song. 2. The actuator was used to make a detailed analysis of the mechanics of sound production, with particular reference to the emission of the more or less pure tone at 15 kHz., characteristic of Homorocoryphus nitidulus. 3. Results involving damping and cautery indicated that the area of the right tegmen responsible for the radiation of this sound was the mirror frame, the vein enclosing the classical mirror membrane. 4. Further experiments involving transduced sound and a probe microphone led to the construction of sound radiation maps of the right tegmen which supported the above view. 5. The cantilever hypothesis, involving the mirror frame with the axis of the vestigial file as the cantilever's rotational axis, was considered in the light of the Homorocoryphus type. 6. The Homorocoryphus type differed from the Conocephalus type (on which the cantilever hypothesis was based) in that a simpler cantilever is formed in a line direct from the plectrum to the tip of the frame arm.

scholarly journals A Novel Approach for Efficient Forgery Image Detection Using Hybrid Feature Extraction and Classification

2018 ◽  
Vol 7 (3.27) ◽  
pp. 215
Author(s):  
G Clara Shanthi ◽  
V Cyril Raj
Keyword(s):  
Feature Extraction ◽  
Support Vector ◽  
Forgery Detection ◽  
Image Splicing ◽  
Image Forgery ◽  
Second Stage ◽  
Image Forgery Detection ◽  
Novel Approach ◽  
Different Types ◽  
Hybrid Feature Extraction

Image forgery detection is developing as one of the major research topic among researchers in the area of image forensics. These image forgery detection is addressed by two different types: (i) Active, (ii) Passive. Further consist of some different methods, such as Copy-Move, Image Splicing, and Retouching. Development of the image forgery is very necessary to detect as the image is true or it is forgery. In this paper, an efficient forgery detection and classification technique is proposed by three different stages. At first stage, preprocessing is carried out using bilateral filtering to remove noise. At second stage, extract unique features from forged image by using efficient feature extraction technique namely Gray Level Co-occurance Matrices (GLCM). Here, the GLCM improves the feature extraction accuracy. Finally, forged image is detected by classifying the type of image forgery using Multi Class- Support Vector Machine (SVM). Also, the performance of the proposed method is analyzed using the following metrics: accuracy, sensitivity and specificity.  

scholarly journals Fabric Defect Detection Using the Sensitive Plant Segmentation Algorithm

2020 ◽  
Vol 28 (3(141)) ◽  
pp. 84-87
Author(s):  
M. Fathu Nisha ◽  
P. Vasuki ◽  
S. Mohamed Mansoor Roomi
Keyword(s):  
Defect Detection ◽  
Textile Industry ◽  
Segmentation Algorithm ◽  
Second Stage ◽  
Fabric Defect Detection ◽  
Fabric Defect ◽  
Different Types ◽  
Improved Performance ◽  
Two Stages ◽  
Defective Pixel

Fabric quality control and defect detection are playing a crucial role in the textile industry with the development of high customer demand in the fashion market. This work presents fabric defect detection using a sensitive plant segmentation algorithm (SPSA) which, is developed with the sensitive behaviour of the sensitive plant biologically named “mimosa pudica”. This method consists of two stages: The first stage enhances the contrast of the defective fabric image and the second stage segments the fabric defects with the aid of the SPSA. The SPSA proposed was developed for defective pixel identification in non-uniform patterns of fabrics. In this paper, the SPSA was built through checking with devised conditions, correlation and error probability. Every pixel was checked with the algorithm developed to be marked either a defective or non-defective pixel. The SPSA proposed was tested on different types of fabric defect databases, showing a much improved performance over existing methods.

scholarly journals Method of critical control of atmospheric radiosounding data in the range of extreme deviations

2019 ◽  
pp. 23-32
Author(s):  
M. V. Savenets
Keyword(s):  
Control Method ◽  
Lower Troposphere ◽  
Threshold Values ◽  
Night Time ◽  
Total Period ◽  
Control Techniques ◽  
Second Stage ◽  
Total Percentage ◽  
Different Types ◽  
Distribution Parameters

The paper presents a new method of critical control of atmospheric radiosounding data in the range of extreme deviations of air temperature, isobaric level elevation, relative humidity and wind components. The method was developed based on atmospheric radiosounding data taken from 9 Ukrainian aerological stations over the period of 1973–2018. “Buoyant” threshold values form the basis of the developed method. These values correspond to the deviation threshold for each of aerological characteristics where statistical distribution of such characteristics reaches a zero value for the first time. Departure from constant threshold values in favor of “buoyant” values allowed for consideration of the main features of aerological characteristics dispersion, dependence from altitude and difference of distribution parameters observed during daylight and at night time. Potential errors in the range of extreme deviations may be identified when the values go beyond the thresholds of "the distribution body". The total percentage of such overrange amounts to 0.2% in the middle and upper troposphere, 0.3–1.8% in the lower troposphere, and up to 2% in the stratosphere. At the second stage of the developed method potential errors are checked using partial vertical, partial horizontal and temporal control techniques. The second stage of control is implemented for the levels where time series reach at least 3700 values. It allows for accurate calculation of average multi-year values required for performing the horizontal control. Potential errors are considered as real ones if there is a confirmation of existence of three extreme deviations taken from the “neighbor stations – neighbor observation periods – neighbor isobaric levels” set. It means that a potential error should be confirmed with at least two different types of critical control. At high altitudes two confirmations are enough provided a conclusion is made following the results of different types of control. The developed critical control method allowed rejection of the claim about incorrectness of 568 values with their maximum deviations reaching 6.2 and -6.4 σ for the total period of observation. The critical control of extreme deviations and the physical permissible limits control form necessary components of the complex critical control of atmospheric radiosounding data. They provide input information used for horizontal, vertical and hydrostatic control techniques.

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