Статті в журналах: "Vibrational Monitoring"

1

Feng, Jianxiong, Yangfan Liu, and Kai Ming Li. "Vibrational Monitoring of Nested Planetary Geartrain with Unground Pinion." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 5 (August 1, 2021): 1471–87. http://dx.doi.org/10.3397/in-2021-1852.

Повний текст джерела

Анотація:

The nested planetary gear train, which has two integrated single-stage planetary gearsets, is one of the newly developed compound gear train that has been successfully applied to the automobile transmissions. In the current study, a certain type of gear fault in the nested gear train, ungrounded pinion, is investigated using a non-destructive approach monitoring its vibration levels. A novel experimental test stand with open and vertical setup has been designed to collect the vibrational data by mounting the accelerometer directly to the gear clutches. Each of the two layers of the compound gear was tested separately. The measured vibrational data were processed with several signal processing techniques, which includes (a) frequency spectrum analysis, (b) time synchronous averaging (TSA) and (c) modulation sideband analysis. The experimental results show that the existence of the ungrounded pinion can be identified with the frequency spectrum analysis of the vibrational data. In addition, the modulation sidebands are also modeled using a modified version of the traditional technique of physical signal modeling. It is shown that the relative phase of the planet and the meshing vibration strength changed by the unground gear is the critical factor for determining the modulation sideband behavior. In addition, the location of the ungrounded pinion can also be determined by the time history processed by TSA.

Стилі APA, Harvard, Vancouver, ISO та ін.

2

Mohanty, Lipi, Yaowen Yang, and Swee Tjin. "Passively Conducted Vibration Sensing with Fiber Bragg Gratings." Applied Sciences 8, no. 9 (September 10, 2018): 1599. http://dx.doi.org/10.3390/app8091599.

Повний текст джерела

Анотація:

Measuring vibrations is a common method of monitoring the integrity of structures and heavy machinery, that are subject to dynamic loads. Strong vibrations for prolonged periods of time can be caused by various sources, such as trains, motors and heavy machinery. These strong vibrations should be identified and managed to ensure operational safety. This study proposes a flexible metal beam sensor with a fiber Bragg grating (FBG) mounted on the surface to measure the vibrational frequency. We present a sensor for measuring the vibrational frequencies on-site by placing the beam so that it makes physical contact with the vibrating body. The sensor has been tested in the range of 50–200 Hz. The sensing beam can detect the vibrations that are induced in other metallic bodies where there are metallic structures of low stiffness to conduct the vibration. The results show that the sensing beam is capable of detecting the frequency of forced vibrations from its periphery when placed in different orientations.

Стилі APA, Harvard, Vancouver, ISO та ін.

3

Muscat, Andrew, Soham Bhattacharya, and Yong Zhu. "Electromagnetic Vibrational Energy Harvesters: A Review." Sensors 22, no. 15 (July 25, 2022): 5555. http://dx.doi.org/10.3390/s22155555.

Повний текст джерела

Анотація:

As industries need more real-time monitoring and interconnected systems, the demand for wireless sensors expands. Vibrational energy harvesters are a potential solution for powering these sensors, as vibrations commonly exist where monitoring occurs. Developments in low-power circuitry have also led to the feasibility of these types of harvesters. Electromagnetic harvesters are a standout among various types of vibrational harvesters due to their ability to capture kinetic energy in a low-frequency range. This leads to these devices being more applicable in real-world applications where ambient vibrations are typical of having low frequencies. Hence, extensive research has been undertaken to make electromagnetic harvesters more efficient and compact. This review study aims to examine recent literature that has made advancements and demonstrated the full potential of such devices.

Стилі APA, Harvard, Vancouver, ISO та ін.

4

Townsend, Scott, Stephen Grigg, Renato Picelli, Carol Featherston, and Hyunsun Alicia Kim. "Topology optimization of vibrational piezoelectric energy harvesters for structural health monitoring applications." Journal of Intelligent Material Systems and Structures 30, no. 18-19 (September 22, 2019): 2894–907. http://dx.doi.org/10.1177/1045389x19873392.

Повний текст джерела

Анотація:

Aircraft structures exhibit localized vibrations over a wide range of frequencies. Such vibrations can be used to power sensors which then monitor the health of the structure. Conventional vibrational piezoelectric harvesting involves optimizing the harvester for one distinct frequency. The aim of this work is to design a wireless vibrational piezoelectric system capable of energy harvesting in the range of 100–500 Hz by tailoring the resonant behavior of cantilever structures. We herein employ a model capable of predicting the performance of a piezoelectric cantilever retrofit on a structural health monitoring sensor and then formulate a design optimization problem and solve with the level set topology optimization method. The designs are verified through fabrication of experimental prototypes.

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Muszynska, Agnes. "Vibrational Diagnostics of Rotating Machinery Malfunctions." International Journal of Rotating Machinery 1, no. 3-4 (1995): 237–66. http://dx.doi.org/10.1155/s1023621x95000108.

Повний текст джерела

Анотація:

This paper outlines rotating machinery malfunction diagnostics using vibration data in correlation with operational process data. The advantages of vibration monitoring systems as a part of preventive/predictive maintenance programs are emphasized. After presenting basic principles of machinery diagnostics, several specific malfunction symptoms supported by simple mathematical models are given. These malfunctions include unbalance, excessive radial load, rotor-to-stator rubbing, fluid-induced vibrations, loose stationary and rotating parts, coupled torsional/lateral vibration excitation, and rotor cracking. The experimental results and actual field data illustrate the rotor vibration responses for individual malfunctions. Application of synchronous and nonsynchronous perturbation testing used for identification of basic dynamic characteristics of rotors is presented. Future advancements in vibration monitoring and diagnostics of rotating machinery health are discussed. In the Appendix, basic instrumentation for machine monitoring is outlined.

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Ben-Romdhane, Mohamed. "Condition based monitoring by vibrational analysis." Journal of the Acoustical Society of America 112, no. 1 (2002): 17. http://dx.doi.org/10.1121/1.1500897.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

7

Panayanthatta, Namanu, Giacomo Clementi, Merieme Ouhabaz, Mario Costanza, Samuel Margueron, Ausrine Bartasyte, Skandar Basrour, et al. "A Self-Powered and Battery-Free Vibrational Energy to Time Converter for Wireless Vibration Monitoring." Sensors 21, no. 22 (November 11, 2021): 7503. http://dx.doi.org/10.3390/s21227503.

Повний текст джерела

Анотація:

Wireless sensor nodes (WSNs) are the fundamental part of an Internet of Things (IoT) system for detecting and transmitting data to a master node for processing. Several research studies reveal that one of the disadvantages of conventional, battery-powered WSNs, however, is that they typically require periodic maintenance. This paper aims to contribute to existing research studies on this issue by exploring a new energy-autonomous and battery-free WSN concept for monitor vibrations. The node is self-powered from the conversion of ambient mechanical vibration energy into electrical energy through a piezoelectric transducer implemented with lead-free lithium niobate piezoelectric material to also explore solutions that go towards a greener and more sustainable IoT. Instead of implementing any particular sensors, the vibration measurement system exploits the proportionality between the mechanical power generated by a piezoelectric transducer and the time taken to store it as electrical energy in a capacitor. This helps reduce the component count with respect to conventional WSNs, as well as energy consumption and production costs, while optimizing the overall node size and weight. The readout is therefore a function of the time it takes for the energy storage capacitor to charge between two constant voltage levels. The result of this work is a system that includes a specially designed lead-free piezoelectric vibrational transducer and a battery-less sensor platform with Bluetooth low energy (BLE) connectivity. The system can harvest energy in the acceleration range [0.5 g–1.2 g] and measure vibrations with a limit of detection (LoD) of 0.6 g.

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Loss, Theresa, and Alexander Bergmann. "Vibration-Based Fingerprint Algorithm for Structural Health Monitoring of Wind Turbine Blades." Applied Sciences 11, no. 9 (May 10, 2021): 4294. http://dx.doi.org/10.3390/app11094294.

Повний текст джерела

Анотація:

Monitoring the structural health of wind turbine blades is essential to increase energy capture and operational safety of turbines, and therewith enhance competitiveness of wind energy. With the current trends of designing blades ever longer, detailed knowledge of the vibrational characteristics at any point along the blade is desirable. In our approach, we monitor vibrations during operation of the turbine by wirelessly measuring accelerations on the outside of the blades. We propose an algorithm to extract so-called vibration-based fingerprints from those measurements, i.e., dominant vibrations such as eigenfrequencies and narrow-band noise. These fingerprints can then be used for subsequent analysis and visualisation, e.g., for comparing fingerprints across several sensor positions and for identifying vibrations as global or local properties. In this study, data were collected by sensors on two test turbines and fingerprints were successfully extracted for vibrations with both low and high operational variability. An analysis of sensors on the same blade indicates that fingerprints deviate for positions at large radial distance or at different blade sides and, hence, an evaluation with larger datasets of sensors at different positions is promising. In addition, the results show that distributed measurements on the blades are needed to gain a detailed understanding of blade vibrations and thereby reduce loads, increase energy harvesting and improve future blade design. In doing so, our method provides a tool for analysing vibrations with relation to environmental and operational variability in a comprehensive manner.

Стилі APA, Harvard, Vancouver, ISO та ін.

9

Kajita, Masatoshi. "Non-destructive Monitoring of Molecular Vibrational Transitions." Journal of the Physical Society of Japan 87, no. 7 (July 15, 2018): 074301. http://dx.doi.org/10.7566/jpsj.87.074301.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

10

Brown, Sandra E., Andreas W. Götz, Xiaolu Cheng, Ryan P. Steele, Vladimir A. Mandelshtam, and Francesco Paesani. "Monitoring Water Clusters “Melt” Through Vibrational Spectroscopy." Journal of the American Chemical Society 139, no. 20 (May 12, 2017): 7082–88. http://dx.doi.org/10.1021/jacs.7b03143.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

11

Hashimoto, Katsufumi, Tomoki Shiotani, Hiroyuki Mitsuya, and Kai-Chun Chang. "MEMS Vibrational Power Generator for Bridge Slab and Pier Health Monitoring." Applied Sciences 10, no. 22 (November 21, 2020): 8258. http://dx.doi.org/10.3390/app10228258.

Повний текст джерела

Анотація:

Micro energy harvesters (MEH) based on microelectromechanical systems (MEMS) are rapidly developing, providing a green and virtually infinite energy source. The electrostatic vibratory power generator outputs electric power when it vibrates, motivating us to apply it to vibrating civil infrastructures excited by ambient and daily traffic loadings. In this study, an innovative monitoring system utilizing MEH devices was proposed for detecting slab damage and pier scours for bridge structures. Its performance was numerically investigated with finite element models, where the damage in slabs was modeled with a reduced Young’s modulus and scours with fixed boundaries of inclined depth. It was shown that the powers generated at each MEH varied as the target structure’s modal frequency shifted and amplitude changed by damage or scour. A power generation index was proposed to identify slab damage and a reference-free method was introduced to detect uneven pier scours. Utilizing an electrostatic vibration-based MEH (MEMS vibrational power generator), this pioneering study showed that MEMS vibrational power generators can work as sensors for an infrastructure structural health monitoring system.

Стилі APA, Harvard, Vancouver, ISO та ін.

12

Grigoriev, Sergey N., Mikhail P. Kozochkin, Artur N. Porvatov, Sergey V. Fedorov, Alexander P. Malakhinsky, and Yury A. Melnik. "Investigation of the Information Possibilities of the Parameters of Vibroacoustic Signals Accompanying the Processing of Materials by Concentrated Energy Flows." Sensors 23, no. 2 (January 9, 2023): 750. http://dx.doi.org/10.3390/s23020750.

Повний текст джерела

Анотація:

Creating systems for monitoring technology processes based on concentrated energy flows is an urgent and challenging task for automated production. Similar processes accompany such processing technologies: intensive thermal energy transfer to the substance, heating, development of the melting and evaporation or sublimation, ionization, and expansion of the released substance. It is accompanied by structural and phase rearrangements, local changes in volumes, chemical reactions that cause perturbations of the elastic medium, and the propagation of longitudinal and transverse waves in a wide frequency range. Vibrational energy propagates through the machine’s elastic system, making it possible to register vibrations on surfaces remotely. Vibration parameters can be used in monitoring systems to prevent negative phenomena during processing and to be a tool for understanding the processes’ kinetics. In some cases, it is the only source of information about the progress in the processing zone.

Стилі APA, Harvard, Vancouver, ISO та ін.

13

Oliinyk, O. Yu. "VIBRATION FREQUENCY DENSITY CONTROL METHOD IN VIBRATION CONDITIONS." METHODS AND DEVICES OF QUALITY CONTROL, no. 2(43) (December 24, 2019): 41–47. http://dx.doi.org/10.31471/1993-9981-2019-2(43)-41-47.

Повний текст джерела

Анотація:

The use of existing vibration frequency measuring instruments for monitoring technological parameters inside apparatus and equipment is limited due to the presence of vibrations and industrial noise. The lack of data on the use of part of the technological apparatus as flow resonators through the unexplored basic analytical equations for determining the amplitude-frequency characteristics of such resonators determined the direction of these studies. The article is devoted to studies aimed at establishing the relationship between the vibrational field of the resonator, which is used as part of the technological apparatus with a controlled environment, and its reaction in the form of a change in the frequency or amplitude of the resonator’s own vibrations, which carries information about the properties of the substance in the apparatus. The experimental setup diagram, experimental methodology, and data on determining the oscillation frequency of the resonator under vibration conditions for metallic (corrosion-resistant steel) and non-metallic (organic glass) resonators are presented. The curves obtained from the experimental values were approximated using linear and hyperbolic approximations. It was found that the use of hyperbolic approximation reduces the average approximation error by more than six times. It was found that the error of the hyperbolic approximation error does not exceed 0.022% for a metal resonator and 0.05% for an organic glass resonator. The conducted experimental studies confirm the presence of a determinate coupling of the measured frequency characteristics of the resonator with the density, which was measured inside the equipment. The obtained data was used to develop the scientific and methodological foundations of the vibrational frequency control method in conditions of vibration using a part of the device as a resonator of the vibrational frequency sensor.

Стилі APA, Harvard, Vancouver, ISO та ін.

14

Bodini, Ileana, Matteo Lancini, Simone Pasinetti, and David Vetturi. "Techniques for on-board vibrational passenger comfort monitoring in public transport." ACTA IMEKO 3, no. 4 (December 1, 2014): 32. http://dx.doi.org/10.21014/acta_imeko.v3i4.152.

Повний текст джерела

Анотація:

Traffic calming devices on urban streets, such as elevated pedestrian crossings, speed bumps and roundabouts, are increasingly used, raising a real problem in relation to the on-board comfort that passengers perceive. To measure vibrational comfort related to traffic calming devices that passengers of the public transport perceive, an acquisition system called ASGCM (Autonomous System for Geo-referenced Comfort Measurements) has been developed, taking as a reference the European regulations on rail transports. ASGCM permits to link each measurement of vibration, ground velocity and acceleration with geographical information resulting from a GPS. In this way a map of a comfort index, statistical surveys and correlation between on-board comfort and traffic calming, can be directly obtained by any Geographic Information System (GIS), able to query a centralized remote database, which was developed ad- hoc. A large number of experimental tests has been performed to define a vibrational comfort index and to collect a large dataset that allows statistically significant comparisons between different infrastructures and their characterization. The proposed technique can also be useful for diagnostics purposes, such as vehicle comparison and road maintenance state monitoring.

Стилі APA, Harvard, Vancouver, ISO та ін.

15

Cassiday, Laura, and Laura Cassiday. "Good vibrations: online and at-line monitoring of edible oils with vibrational spectroscopy." INFORM: International News on Fats, Oils, and Related Materials 27, no. 7 (July 1, 2016): 6–13. http://dx.doi.org/10.21748/inform.07.2016.06.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

16

Sergeev, Yu S., S. V. Sergeev, A. A. D’yakonov, A. V. Kononistov, G. E. Karpov, and A. A. Mikryukov. "Automated Monitoring System for Self-Synchronizing Vibrational Drives." Russian Engineering Research 38, no. 2 (February 2018): 86–90. http://dx.doi.org/10.3103/s1068798x18020168.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

17

Olinga, A., and H. W. Siesler. "Quality Control and Process Monitoring by Vibrational Spectroscopy." NIR news 11, no. 3 (June 2000): 9–13. http://dx.doi.org/10.1255/nirn.567.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

18

Zhang, Wei Cong, Zheng Wu Dai, Wen Xiang Zhang, and Ji Zhang. "Research on Transformer Monitoring System Based on Vibrational Spectroscopy." Advanced Materials Research 765-767 (September 2013): 2238–41. http://dx.doi.org/10.4028/www.scientific.net/amr.765-767.2238.

Повний текст джерела

Анотація:

Power transformers vibration principle was analyzed, using vibration spectroscopy, design and development of a power transformer online monitoring system, through the transformer vibration monitoring, to indirectly infer the DC magnetic bias circumstances, Realized condition monitoring of Substation. This paper describes the system works, the constituent modules and the corresponding indicator characteristics, proposed monitoring algorithm optimization, Given the interface of real-time monitoring data, historical data, system was running good, stable and reliable.

Стилі APA, Harvard, Vancouver, ISO та ін.

19

Thanagasundram, S., and F. S. Schlindwein. "Comparison of integrated micro-electrical-mechanical system and piezoelectric accelerometers for machine condition monitoring." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 220, no. 8 (August 1, 2006): 1135–46. http://dx.doi.org/10.1243/09544062c07405.

Повний текст джерела

Анотація:

The design and implementation of instrumentation to collect real-time vibrational data from a quasi-steady state machine (a dry vacuum pump) for fault prediction diagnostics is presented. When simultaneous multiple data collection points are required on the same machinery, the use of conventional transducers such as piezoelectric accelerometers becomes impractical due to their price, as each needs an expensive associated charge amplifier. The use of inexpensive micromachined integrated micro-electrical-mechanical system accelerometers such as ADXL105 has been explored here as an alternative to piezoelectric accelerometers for obtaining reliable and predictable data for diagnostics. Surface micromachined accelerometers are a new technology and their usage for vibrational analysis has been conservative due to concerns over increased noise levels and tolerance to high temperatures. In this article, it is shown that such concerns can be allayed. The time and frequency domain vibration signatures obtained using both types of accelerometers are compared. The study shows that ADXL105 accelerometers can be an effective alternative low-cost high-quality solution for machine condition monitoring.

Стилі APA, Harvard, Vancouver, ISO та ін.

20

Ouis, Djamel. "Monitoring of a Cross-Sectional Vibrational Mode in the Trunk of a Palm Tree." Arboriculture & Urban Forestry 46, no. 4 (July 1, 2020): 307–18. http://dx.doi.org/10.48044/jauf.2020.022.

Повний текст джерела

Анотація:

Palm trees, like all other tree species, are living entities that may be subject to the attack of several natural agents which affect the strength of the trunk. The most serious of these damaging agents are parasites and rot fungi, which proliferate in the substance of the stem, destroying its cells and fibers and weakening it. Consequently, this decay affects the physical characteristics of the modes of vibration in the tree trunk regarding resonance frequency, shape, and damping. Advanced stages of rot infection in a tree trunk may reach such an extreme level that substantial amounts of its solid mass are removed, ultimately leading to a hollow trunk rather than one of substance. In cases like these, the trunk presents less resistance to forced vibrations, and the active modes affecting the cross section of the trunk exhibit decreased resonance frequency values. This paper aims to present a method based on vibrations which might be employed for tracking a specific mode of radial vibrations known as the ovalling mode. To achieve this goal, the trunk of a palm tree was set into vibration via mechanical excitation in the radial direction and its response at some specific point on the trunk was examined. This method uses a single concentrated source of excitation and two vibration sensors, which are diametrically positioned and fastened to the surface of the tree trunk. The ovalling mode might be extracted from the frequency response by adding the signals recorded by the two sensors, which are in phase for a test specimen with a perfectly circular, cylindrical shape made of homogeneous, isotropic material. This study provides a preliminary investigation into the feasibility and reliability of this nondestructive method when applied for the identification of rot hosting by the trunks of standing trees, wooden poles, and logs, as well as the level of severity of rot attack.

Стилі APA, Harvard, Vancouver, ISO та ін.

21

Sinou, Jean-Jacques. "Damage Detection in a Rotor Dynamic System by Monitoring Nonlinear Vibrations and Antiresonances of Higher Orders." Applied Sciences 12, no. 23 (November 22, 2022): 11904. http://dx.doi.org/10.3390/app122311904.

Повний текст джерела

Анотація:

Since rotor systems are very sensitive and vulnerable to transverse crack, early detection of damage is of paramount importance and essential for rotating machinery. Therefore, one of the main issues is to identify robust characteristics of the rotor vibration response that can be directly attributed to the presence of a transverse crack in a rotating shaft, preferably when the crack is small enough, in order to avoid catastrophic failures of rotating machines. This study investigates the potential links between the nonlinear vibrations and the locations of higher-order antiresonances and structural modifications due to the presence of a breathing crack in rotor systems. Using the proposed numerical results on the evolution of the nonlinear responses of a cracked rotor system, it was observed that a robust diagnostic of the presence of slight damage can be conducted by tracking nonlinear vibrational measurements, with particular attention to the antiresonance behavior of higher orders. These observations can easily serve as target observations for the monitoring system and for identifying the positions of damage at an early stage.

Стилі APA, Harvard, Vancouver, ISO та ін.

22

Gnanasekaran, Sakthivel, Lakshmipathi Jakkamputi, Mohanraj Thangamuthu, Senthil Kumar Marikkannan, Jegadeeshwaran Rakkiyannan, Kannan Thangavelu, and Gangadhar Kotha. "Condition Monitoring of an All-Terrain Vehicle Gear Train Assembly Using Deep Learning Algorithms with Vibration Signals." Applied Sciences 12, no. 21 (October 27, 2022): 10917. http://dx.doi.org/10.3390/app122110917.

Повний текст джерела

Анотація:

Condition monitoring of gear train assembly has been carried out with vibration signals acquired from an all-terrain vehicle (ATV) gearbox. The location of the defect in the gear was identified based on finite element analysis results. The vibration signals were acquired using an accelerometer under good and simulated fault conditions of the gear. The raw vibration signatures acquired from all the possible conditions of the gear train assembly were processed using the descriptive statistics tool. A set of descriptive statistical features were extracted from the raw vibrational signals. This study used a deep learning algorithm based on the tree family, which includes the decision tree, random forest, and random tree algorithms, to classify gear train conditions. Among the tree family algorithms, the random forest algorithm produced maximum classification accuracy of 99%. The decision rules were used to design an online monitoring system to display the gear condition. This study will help to implement online gear health monitoring in ATVs, ensuring the safety of drivers.

Стилі APA, Harvard, Vancouver, ISO та ін.

23

Yang, Yang, Yao Zhang, and Xiaokun Tan. "Review on Vibration-Based Structural Health Monitoring Techniques and Technical Codes." Symmetry 13, no. 11 (October 22, 2021): 1998. http://dx.doi.org/10.3390/sym13111998.

Повний текст джерела

Анотація:

Structural damages occur in modern structures during operations due to environmental and human factors. The damages accumulating with time may lead to a significant decrease in structure performance or even destruction; natural symmetry is broken, resulting in an unexpected life and economic loss. Therefore, it is necessary to monitor the structural response to detect the damage in an early stage, evaluate the health condition of structures, and ensure the operation safety of structures. In fact, the structure and the evaluation can be considered as a special symmetry. Among several SHM methods, vibration-based SHM techniques have been widely adopted recently. Hence, this paper reviews the vibration-based SHM methods in terms of the vibrational parameters used. In addition, the technical codes on vibration based SHM system have also been reviewed, since they are more important in engineering applications. Several related ISO standards and national codes have been developed and implemented, while more specific technical codes are still required to provide more detailed guidelines in practice to maintain structure safety and natural symmetry.

Стилі APA, Harvard, Vancouver, ISO та ін.

24

Ravera, Francesca, Esen Efeoglu, and Hugh J. Byrne. "Vibrational Spectroscopy for In Vitro Monitoring Stem Cell Differentiation." Molecules 25, no. 23 (November 26, 2020): 5554. http://dx.doi.org/10.3390/molecules25235554.

Повний текст джерела

Анотація:

Stem cell technology has attracted considerable attention over recent decades due to its enormous potential in regenerative medicine and disease therapeutics. Studying the underlying mechanisms of stem cell differentiation and tissue generation is critical, and robust methodologies and different technologies are required. Towards establishing improved understanding and optimised triggering and control of differentiation processes, analytical techniques such as flow cytometry, immunohistochemistry, reverse transcription polymerase chain reaction, RNA in situ hybridisation analysis, and fluorescence-activated cell sorting have contributed much. However, progress in the field remains limited because such techniques provide only limited information, as they are only able to address specific, selected aspects of the process, and/or cannot visualise the process at the subcellular level. Additionally, many current analytical techniques involve the disruption of the investigation process (tissue sectioning, immunostaining) and cannot monitor the cellular differentiation process in situ, in real-time. Vibrational spectroscopy, as a label-free, non-invasive and non-destructive analytical technique, appears to be a promising candidate to potentially overcome many of these limitations as it can provide detailed biochemical fingerprint information for analysis of cells, tissues, and body fluids. The technique has been widely used in disease diagnosis and increasingly in stem cell technology. In this work, the efforts regarding the use of vibrational spectroscopy to identify mechanisms of stem cell differentiation at a single cell and tissue level are summarised. Both infrared absorption and Raman spectroscopic investigations are explored, and the relative merits, and future perspectives of the techniques are discussed.

Стилі APA, Harvard, Vancouver, ISO та ін.

25

Miners, J. H., R. Martin, P. Gardner, R. Nalezinski, and A. M. Bradshaw. "Monitoring adsorbed species during oscillatory reactions using vibrational spectroscopy." Surface Science 377-379 (April 1997): 791–95. http://dx.doi.org/10.1016/s0039-6028(96)01504-x.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

26

Xue, Gang, Wei Yu Bai, and Xian Wang. "Finite Element Model Updating of a Prestressed Concrete Continuous Bridge Based on Dynamic Monitoring." Applied Mechanics and Materials 405-408 (September 2013): 1645–50. http://dx.doi.org/10.4028/www.scientific.net/amm.405-408.1645.

Повний текст джерела

Анотація:

The finite element model modified technique based on optimization principle is benefit for the model updating of the large bridge structures. By the ambient vibration test information provided by health monitoring system of huanghe bridge II in baotou , this article adopted corrected parameter based on structural eigenvalue sensitivity analysis to update the bridge dynamic model.The fundamental vibrational frequency of updated finite element model is more closer to the measured result under ambient excitation, which indicates that the optimization algorithm provided by large-scale general software can carry out the model updating effectively.

Стилі APA, Harvard, Vancouver, ISO та ін.

27

Hope, V. S., and D. M. Hiller. "The prediction of groundborne vibration from percussive piling." Canadian Geotechnical Journal 37, no. 3 (June 1, 2000): 700–711. http://dx.doi.org/10.1139/t99-130.

Повний текст джерела

Анотація:

Environmental assessments of proposed infrastructure projects include an appraisal of the vibration that would be generated by potential construction methods. This paper considers one part of that process: prediction of groundborne vibration from percussive piling. Various methods for predicting the magnitude of the groundborne vibration generated by percussive piling have been described in the literature. In general, the accuracy of the predictors is limited. The paper investigates the reasons for this, through the development of theoretical models and analysis of field data from an extensive programme of on-site vibration monitoring. It is found that some widespread assumptions about the relationship between the energy rating of a percussive piling hammer and the vibrational energy developed in the ground are invalid. Ground conditions are shown to have a dominant influence on the magnitude of the groundborne vibration generated by percussive piling, and piling vibration predictors which take no account of soil type yield considerably less accurate estimates than site-specific predictions.Key words: piling, vibration, monitoring, prediction, environmental assessment.

Стилі APA, Harvard, Vancouver, ISO та ін.

28

Zaalishvili, Vladislav, Dmitry Melkov, and Aleksandr Kanukov. "SPECTRAL FEATURES OF THE MICROSEMIC FIELD OF THE URBANIZED TERRITORY." Akustika 32 (March 1, 2019): 279–83. http://dx.doi.org/10.36336/akustika201932279.

Повний текст джерела

Анотація:

Currently, seismic monitoring is considered as a geophysical technique for recording and determining earthquake parameters. This determines the distribution of such type of monitoring in seismic areas. At the same time, seismic signals carry important information about various natural phenomena and the human impact on the environment. Registration of microseismic vibrations allows to determine the resonant features of the soil strata, which can enhance the vibrations during earthquakes, as well as during the operation of various mechanisms, causing structural damage and such a phenomenon as vibrational liquefaction of clay soils. The paper analyzes the data of long-term observations of microseismic noise in an urbanized area by the network of seismological observations Vladikavkaz and mobile stations. Daily variations of the microseismic field are shown and a map of the predominant frequencies of microseismic vibrations due to the influence of ground conditions is compiled.

Стилі APA, Harvard, Vancouver, ISO та ін.

29

Abboud, D., M. Elbadaoui, S. Becquerelle, and M. Lalmi. "The application of the cyclic coherence for distributed planet fault detection in planetary gears." International Journal of Condition Monitoring 8, no. 2 (April 1, 2018): 58–63. http://dx.doi.org/10.1784/204764218823029075.

Повний текст джерела

Анотація:

The vibration-based condition monitoring of planetary gears is a highly active and challenging field of research. Many signal processing techniques have been proposed, with the aim of promoting the fault component in the signal and, consequently, highlighting the fault signature (ie the damage symptom). Most of these techniques consider the fault contribution as being deterministic, which is true in the case of an advanced and localised fault. Such techniques may fail in other scenarios in which, for instance, the fault is of a distributed nature and its vibrational component is weak. In such a case, the fault component is likely to be randomised and turns cyclostationary. The present paper suggests the presence of an additional cyclostationary component in planetary gear vibrations. The presence of this component is explained by the presence of load fluctuations at the meshing points and the random micro-irregularity in the stiffness of gear components, as well as the presence of distributed faults. A simplified signal model is proposed to explain the vibration signal structure of healthy and faulty planetary gears (with a planet fault in the case of the faulty gear). Also, a cyclostationary-based condition monitoring approach is proposed, based on the cyclic coherence. The proposed approach is validated on real-world vibration signals acquired from a planetary gear benchmark.

Стилі APA, Harvard, Vancouver, ISO та ін.

30

McAdams, Daniel A., and Irem Y. Tumer. "Toward Intelligent Fault Detection in Turbine Blades: Variational Vibration Models of Damaged Pinned-Pinned Beams." Journal of Vibration and Acoustics 127, no. 5 (November 29, 2004): 467–74. http://dx.doi.org/10.1115/1.2013296.

Повний текст джерела

Анотація:

Inaccuracies in the modeling assumptions about the distributional characteristics of the monitored signatures have been shown to cause frequent false positives in vehicle monitoring systems for high-risk aerospace applications. To enable the development of robust fault detection methods, this work explores the deterministic as well as variational characteristics of failure signatures. Specifically, we explore the combined impact of crack damage and manufacturing variation on the vibrational characteristics of turbine blades modeled as pinned-pinned beams. The changes in the transverse vibration and associated eigenfrequencies of the beams are considered. Specifically, a complete variational beam vibration model is developed and presented that allows variations in geometry and material properties to be considered, with and without crack damage. To simplify variational simulation, separation of variables is used for fast simulations. This formulation is presented in detail. To establish a baseline of the effect of geometric variations on the system vibrational response, a complete numerical example is presented that includes damaged beams of ideal geometry and damaged beams with geometric variation. It is shown that changes in fault detection monitoring signals caused by geometric variation are small with those caused by damage and impending failure. Also, when combined, the impact of geometric variation and damage appear to be independent.

Стилі APA, Harvard, Vancouver, ISO та ін.

31

Chichkov, B. A. "TECHNIQUE OF PROCESSING OF VIBRATION MONITORING DATA, RECEIVED BY THE USE OF MICROELECTROMECHANICAL SYSTEMS." Civil Aviation High TECHNOLOGIES 22, no. 2 (April 24, 2019): 38–48. http://dx.doi.org/10.26467/2079-0619-2019-22-2-38-48.

Повний текст джерела

Анотація:

During the operation of such machines as aviation engines and land based gas turbines, the obligatory vibration monitoring is carried out which is focused on the prevention of their possible damages and destructions during the work on resonant modes or because of material fatigue. Nowadays, as a rule, the standard or additional equipment is used for such control which includes as a component various types of one-axial vibration gauges. In most cases, the control is carried out continuously, and the frequency of registration can differ from several values for a flight to several values in a second. The data received during routine vibration monitoring is peak values of vibrations. They are diagnosed, using the pre-start control and some ways of fit and the tendency of changes of vibration during the operation. Microelectromechanical systems gaining now the increasing distribution (MEMS), as a rule, allow to obtain the data about vibro-acceleration without giving data about the frequency vibration characteristics. But also the regular equipment of vibrational control used during the operation of considered machines does not give data about the frequency vibration characteristics. However, microelectromechanical devices allow to obtain the data with the essential higher frequency of sample rate (in tens and hundreds times) in comparison with mass equipment used now for control, and to carry out the simultaneous control of vibration on three axes using one gauge. Apart from the vibration peak value the position relative to a reference point is fixed. Does the information received according to mentioned above features have better diagnostic potential? Will the array dimension received during data verification be an obstacle to the operational processing? Materials of the present article are an attempt to give answers to these questions and to make representation about possibility and features of an estimation of a technical state of machines by the results of processing of time series vibro-accelerations received with the use of such processing microelectromechanical systems. It is represented that the way of data processing of vibrating monitoring considered in the article at sufficient simplicity of realization allows to solve the problem of an estimation of a technical state of monitoring item.

Стилі APA, Harvard, Vancouver, ISO та ін.

32

Kandemir, A., F. Iyikanat, and H. Sahin. "Monitoring the crystal orientation of black-arsenic via vibrational spectra." Journal of Materials Chemistry C 7, no. 5 (2019): 1228–36. http://dx.doi.org/10.1039/c8tc05167d.

Повний текст джерела

Анотація:

In this study, the structural, mechanical, and vibrational properties of a recently discovered anisotropic ultra-thin material, black-arsenic (b-As), are investigated by using density functional theory.

Стилі APA, Harvard, Vancouver, ISO та ін.

33

Ye, Shuji, Junjun Tan, Kangzhen Tian, Chuanzhao Li, Jiahui Zhang, and Yi Luo. "Directly monitoring the active sites of charge transfer in heterocycles in situ and in real time." Chemical Communications 55, no. 4 (2019): 541–44. http://dx.doi.org/10.1039/c8cc08452a.

Повний текст джерела

Анотація:

Coherent degenerate infrared-infrared-visible sum frequency generation vibrational spectroscopy provides a powerful label-free probe for identifying the vibrational modes that are coupled through the electronic states in situ and in real time.

Стилі APA, Harvard, Vancouver, ISO та ін.

34

Yousefsani, Seyed Abdolmajid, Hooman Dejnabadi, Olivier Guyen, and Kamiar Aminian. "A Vibrational Technique for In Vitro Intraoperative Prosthesis Fixation Monitoring." IEEE Transactions on Biomedical Engineering 67, no. 10 (October 2020): 2953–64. http://dx.doi.org/10.1109/tbme.2020.2974380.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

35

Hsieh, Kai H., Marvin W. Halling, and Paul J. Barr. "Overview of Vibrational Structural Health Monitoring with Representative Case Studies." Journal of Bridge Engineering 11, no. 6 (November 2006): 707–15. http://dx.doi.org/10.1061/(asce)1084-0702(2006)11:6(707).

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

36

Rüther, Anja, Marcel Pfeifer, Víctor A. Lórenz-Fonfría, and Steffen Lüdeke. "Reaction Monitoring Using Mid-Infrared Laser-Based Vibrational Circular Dichroism." Chirality 26, no. 9 (March 12, 2014): 490–96. http://dx.doi.org/10.1002/chir.22307.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

37

McNavage, William, William Dailey та Hai-Lung Dai. "The ν1 and ν2 vibrational bands of the OCCN radical detected through time-resolved Fourier transform IR emission spectroscopy". Canadian Journal of Chemistry 82, № 6 (1 червня 2004): 925–33. http://dx.doi.org/10.1139/v04-041.

Повний текст джерела

Анотація:

Through monitoring the IR emission from vibrationally excited radicals generated by exothermic photolysis reactions, the CN stretch (ν1) and the CO stretch (ν2) vibrational bands of the cyanooxomethyl radical (OCCN) have been observed for the first time at 2093 cm1 and 1774 cm1, respectively. The OCCN radical was produced through 193 nm photolysis of methyl cyanoformate (NCC(O)OCH3), carbonyl cyanide (NCC(O)CN), and pivaloyl cyanide (NCC(O)C(CH3)3). The IR emission spectra were recorded by using nanosecond time-resolved Fourier transform IR emission spectroscopy. Assignments of the spectral peaks were made based on observed time and pressure dependences of IR emission intensities, ab initio calculations, and two-dimensional cross-spectra correlation analysis. Key words: radical, cyanooxomethyl, OCCN, time-resolved vibrational spectroscopy, FTIR, substituted carbonyl dissociation reactions, two-dimensional cross-spectra correlation analysis

Стилі APA, Harvard, Vancouver, ISO та ін.

38

Akassou, Imane, Livia Zapponi, Vincenzo Verrastro, Marco Ciolli, and Valerio Mazzoni. "Extending the vibroscape to agroecosystems: investigating the influence of abiotic factors and monitoring insect vibrational signaling." PeerJ 10 (November 17, 2022): e14143. http://dx.doi.org/10.7717/peerj.14143.

Повний текст джерела

Анотація:

Environmental conditions are crucial factors that influence communication systems and affect animal behavior. Research in the field of biotremology has improved our understanding of insect behavior, ecology, and evolution. However, the interactions between vibrational signaling and environmental factors are less studied, mainly because of technical issues faced in field trials. We therefore developed and tested an approach to investigate the effect of abiotic factors on insect vibrational signaling and explored its implementation as a monitoring tool for insect vibrational signals, using a vineyard as an agroecosystem model. Our results showed a significant decrease in insect signaling activity during unsuitable conditions of high temperature and wind velocity. We determined for the first time, the daily signaling pattern of the two insect pests, Scaphoideus titanus and Halyomorpha halys, in natural conditions. Biotremology techniques could be profitably used to monitor not only the presence of target pest species but also the biodiversity associated with vibrational signaling insects. In particular, the method implemented in this study could be used as a tool to compare the quality of cultivated areas under different management systems.

Стилі APA, Harvard, Vancouver, ISO та ін.

39

Hofmann, Stephen L. "Vibration Analysis for Preventive Maintenance: A Classical Case History." Marine Technology and SNAME News 24, no. 04 (October 1, 1987): 332–39. http://dx.doi.org/10.5957/mt1.1987.24.4.332.

Повний текст джерела

Анотація:

This paper describes the California Maritime Academy's Vibration Monitoring Program for Preventive Maintenance (PM) onboard the Training Ship Golden Bear(TSGB) and how the program detected a potentially dangerous main engine problem. The discovery of machinery operating faults by using vibrational analysis is not unique to marine engineers, but several factors in the Golden Bear's main engine vibration problem make this case a classical one:the nature and extent of the vibration levels;the timing of events and the way the fault developed;the final location of the fault in relationship to the spot on the engine where the high vibration level occurred; andverification of the fact that a PM vibration program can successfully diagnose faults in operating machinery in the marine environment.

Стилі APA, Harvard, Vancouver, ISO та ін.

40

Wu, Jian, Dao Xiang, Ching-Chung Hsueh, Jörg Rottler, and Reuven Gordon. "In Situ Accurate Analysis of Colloidal Nanoparticles via Four Wave Mixing." MRS Advances 3, no. 14 (2018): 707–9. http://dx.doi.org/10.1557/adv.2017.638.

Повний текст джерела

Анотація:

ABSTRACTFour-wave mixing (FWM) is used to measure the vibrational modes of nanoparticles in solution. The vibrations give information about the particle size, material properties and shape. This method has been used for in-situ monitoring of the growth of nanoparticles with high accuracy, as confirmed by electron microscopy analysis. We observe a threshold in the FWM signal which we believe is from a cavity forming around the nanoparticles that reduces viscous damping. We have observed this effect in molecular dynamics simulations as well.

Стилі APA, Harvard, Vancouver, ISO та ін.

41

Mortimer, B., A. Soler, L. Wilkins, and F. Vollrath. "Decoding the locational information in the orb web vibrations of Araneus diadematus and Zygiella x-notata." Journal of The Royal Society Interface 16, no. 154 (May 2019): 20190201. http://dx.doi.org/10.1098/rsif.2019.0201.

Повний текст джерела

Анотація:

A spider's web is a multifunctional structure that captures prey and provides an information platform that transmits vibrational information. Many physical factors interact to influence web vibration and information content, from vibration source properties and input location, to web physical properties and geometry. The aim of the study was to test whether orb web vibration contains information about the location of the source of vibration. We used finite-element analysis model webs to control and vary major physical factors, investigating webs where spiders use a direct or remote monitoring strategy. When monitoring with eight sensors (legs) at the web centre, a comparison of longitudinal and transverse wave amplitude between the sensors gave sufficient information to determine source direction and distance, respectively. These localization cues were robust to changes in source amplitude, input angle and location, with increased accuracy at lower source amplitudes. When remotely monitoring the web using a single thread connected to the web's hub (a signal thread), we found that locational information was not available when the angle of the source input was unknown. Furthermore, a free sector and a stiff hub were physical mechanisms to aid information transfer, which provides insights for bioinspired fibre networks for sensing technologies.

Стилі APA, Harvard, Vancouver, ISO та ін.

42

Albaghdadi, Anwr M., Masri Baharom, and Shaharin Sulaimana. "Hybrid methodology using balancing optimization and vibration analysis to suppress vibrations in a double crank-rocker engine." Eksploatacja i Niezawodnosc - Maintenance and Reliability 24, no. 1 (December 13, 2021): 53–61. http://dx.doi.org/10.17531/ein.2022.1.7.

Повний текст джерела

Анотація:

This study aims to present mathematical modelling to evaluate and analyze double crankrocker engine performance. The study suggests the use of two methods to reduce system vibration through balancing optimization and vibrational analysis. The combination of both methods acts as a verification method; besides it can be used as a tool for further system design enhancement and condition monitoring. The derived mathematical model is then used for balancing optimization to identify system shaking forces and moments, while variable speed is considered as an added parameter to evolve the optimization process. This factor shows better enhancement in reducing system shaking forces and moments compared to constant speed balancing method. Next, the system characteristics were concluded in terms of mode shapes and natural frequencies using modal and frequency response analysis, which give clear clue for secure system operational ground. Finally, the reduction in system vibrations was translated into engine’s centre of mass velocity, which evaluates balancing process effectiveness and indicate if further enhancement should be conducted.

Стилі APA, Harvard, Vancouver, ISO та ін.

43

Martínez, R. Z., та D. Bermejo. "Experimental determination of the rate of V–V collisional relaxation in 14N2 in its ground (X1Σg+) electronic state between 77 and 300 K". Physical Chemistry Chemical Physics 17, № 19 (2015): 12661–72. http://dx.doi.org/10.1039/c5cp01264c.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

44

Ranjan, Rakesh, Subrata Kumar Ghosh, and Manoj Kumar. "Fault diagnosis of journal bearing in a hydropower plant using wear debris, vibration and temperature analysis: A case study." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 234, no. 3 (March 5, 2020): 235–42. http://dx.doi.org/10.1177/0954408920910290.

Повний текст джерела

Анотація:

Analysis of wear debris, vibration and temperature of journal bearing has been integrated to increase the accuracy in fault diagnosis of a hydropower plant. Samples of used lubricating oil, vibration data and bearing temperature at different intervals were collected. Wear particles and acceleration caused by vibration were analysed for the fault detections. An abnormal increase in the temperature and vibrational energy was observed after 200 days of continuous operations. In the last sample, an abnormal increase in aspect ratio of the wear particles was also observed. Scratches and wiping mark were found over the surface of bearing block and side thrust pad. This confirmed the fault of machine by the analysis of condition monitoring data. Further rectification was done by the replacement of bearing block.

Стилі APA, Harvard, Vancouver, ISO та ін.

45

Sanam, Sadbi Ahmad, Alexander Nakhabov, and Zihad Ul Haque. "Analysis of the vibrational monitoring data regarding VVER type reactor installation." Journal of Physics: Conference Series 1701 (November 2020): 012003. http://dx.doi.org/10.1088/1742-6596/1701/1/012003.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

46

Bégin, Steve, Erik Bélanger, Sophie Laffray, Réal Vallée, and Daniel Côté. "In vivooptical monitoring of tissue pathologies and diseases with vibrational contrast." Journal of Biophotonics 2, no. 11 (November 2009): 632–42. http://dx.doi.org/10.1002/jbio.200910071.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

47

Singh, Vishal. "Deposition of Energy using Piezoelectric Material and its Application in TPMS." International Journal for Research in Applied Science and Engineering Technology 9, no. VI (June 30, 2021): 4236–41. http://dx.doi.org/10.22214/ijraset.2021.36103.

Повний текст джерела

Анотація:

The limited lifespan in portable, remote and implantable devices and the need to recharge or replace batteries periodically has been a consistent issue. Ambient energy can usually be found in the form of thermal energy, vibrational energy and solar energy. Among these energy sources, vibrational energy presents a constant presence in nature and artificial structures. Energy harvesting through piezoelectric materials by extracting power from ambient vibrations is a promising technology. The material is capable to harvest sufficient energy required to make autonomous and self-powered electronic systems. The characteristic of piezoelectric material is electromechanical coupling between electrical and mechanical domains. The design of a piezoelectric device for the purpose of storing the kinetic energy of random vibrations at the wheel of a vehicle is presented. The harvester is optimized to power the Tire Pressure Monitoring System (TPMS). The aim is to make of the value of power and voltage outputs for different input frequency conditions. A typical TPMS system consists of a battery operated one, in this paper bimorph is designed to powering a TPMS commercial feasibility of this option is compared to existing TPMS modules, which require batteries for operation.

Стилі APA, Harvard, Vancouver, ISO та ін.

48

Kumar, Sujesh, M. Lokesha, M. V. Kiran Kumar, and C. G. Ramachandra. "Fault Diagnosis in Belt Transmission Using Wavelet Enveloped Spectrum." IOP Conference Series: Materials Science and Engineering 1013, no. 1 (January 1, 2021): 012025. http://dx.doi.org/10.1088/1757-899x/1013/1/012025.

Повний текст джерела

Анотація:

Abstract In the recent years, there is a need for the evolution of methodologies for vibrational analysis by condition monitoring. In this regard, wavelet analysis has become a tool to efficiently detect the features of any vibration signal. The application of wavelet analysis for finding fault in the belt drive is presented in this paper. Vibration signal has been obtained from a healthy and faulty belt drive using a belt drive testing apparatus for experimental studies. The fault diagnostic capability of wavelet analysis has been compared by processing an experimental data. The experiment is done for various working conditions of belt drive. The advantages of wavelet analysis is shown in comparison with Fast Fourier Transform.

Стилі APA, Harvard, Vancouver, ISO та ін.

49

Sullivan, Nicola Jayne, Sabina Avosani, Ruth C. Butler, and Lloyd D. Stringer. "Vibrational Communication of Scolypopa australis (Walker, 1851) (Hemiptera: Ricaniidae)—Towards a Novel Sustainable Pest Management Tool." Sustainability 14, no. 1 (December 24, 2021): 185. http://dx.doi.org/10.3390/su14010185.

Повний текст джерела

Анотація:

A study was undertaken to determine whether Scolypopa australis, the passionvine hopper, communicates using substrate-borne vibrations, as its use of such signals for communication is currently unknown. This insect is a costly pest to the kiwifruit industry in New Zealand, where few pest management tools can be used during the growing season. Vibrations emitted by virgin females and males of S. australis released alone on leaves of Griselinia littoralis were recorded with a laser vibrometer to identify and characterise potential spontaneous calling signals produced by either sex. In addition to single-insect trials, preliminary tests were conducted with female–male pair trials to determine whether individuals exchanged signals. The signal repertoire of S. australis includes a male calling signal and two female calling signals. However, no evidence of duetting behaviour that is potentially necessary for pair formation has been found to date. Our outcome suggests that a deeper understanding of the role of vibrational communication employed by S. australis is needed, and by disclosing the pair formation process, a new residue-free pest management tool against this pest may be developed. In addition, this vibration-based tool could contribute to future biosecurity preparedness and response initiatives.

Стилі APA, Harvard, Vancouver, ISO та ін.

50

Belovolova, L., M. Belovolov, V. Paramonov, M. Belovolov, M. Svistushkin, and A. Lunicheva. "METHODOLOGY FOR STUDYING THE VIBRATIONAL ACTIVITY OF THE VOCAL FOLDS." Russian Journal of Biological Physics and Chemisrty 7, no. 2 (November 15, 2022): 314–19. http://dx.doi.org/10.29039/rusjbpc.2022.0521.

Повний текст джерела

Анотація:

In order to develop equipment for diagnosing the state of the human vocal folds (VF) and monitoring their activity during treatment, a complex of studies of animal VF samples (rabbits) was performed. A highly sensitive non-contact laser-optical equipment and a technique for recording VF vibrations in an air flow with controlled pressure have been developed. For a group of rabbits of the same age, data are given on the registration of vibrational frequencies in healthy VFs and received as a result of therapeutic effects ("treated" VFs). It was found that when air is passed through the trachea under a slight pressure of 10-20 mm Hg. three peaks of the characteristic frequencies of natural mechanical vibrations of the VF appear in the range of ~ 200 - 1000 Hz. As a rule, this is the fundamental frequency f1 and its two harmonics f2 = 2 f1 and f3 = 3 f1. Best of all, these oscillations are excited at the end of the outflow of air under a pressure of 1 - 5 mm Hg. A difference was found in the excited vibrations at low frequencies in healthy VF and VF with defects in the form of a scar on one ligament. The frequencies of the lowest natural vibrations in a defective VF are somewhat higher compared to the lowest frequency in a healthy VF, which is explained by an increase in its rigidity during the formation of scar tissue. The technique is characterized by ease of registration, sensitivity and informativeness during treatment by methods of regenerative medicine. Diagnosis of the state of the VF during treatment in comparison with the data for a healthy VF seems to be informative and useful for restoring the vibrational properties of the vocal cords during the treatment.

Стилі APA, Harvard, Vancouver, ISO та ін.

Статті в журналах з теми "Vibrational Monitoring"

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями