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Nowadays, Long sequences observations and modeling of artificial upwelling area is the key research direction in artificial upwelling. The traditional single point observations are not representative to the artificial upwelling region where environmental parameters are uneven distribution or change is complex. In order to obtain real-time, continuous and large-scale flow rate and temperature distribution...
Bonding dynamics during ultrasonic bonding of Cu free air ball (FAB) is investigated by measuring dynamic strain with piezoresistive strain sensor. Change in dynamic strain with elevating substrate temperature up to 200°C was investigated. It was clearly observed that elevating substrate temperature significantly enhanced deformation of the Cu FAB while the application of pressing load and ultrasonic...
With the growth of the population in the world, energy problem has become a major topic in the world. Energy conservation has become an important part of China's national development strategy. The use of microwave heating instead of traditional heating can greatly improve the utilization rate of energy, and then achieve the goal of energy conservation and emissions reduction. However, due to the uneven...
Lamb wave gas sensor has broad industrial application prospects in gas sensing due to its multi-mode characteristic. Lamb wave gas sensor is now still in fundamental academic research period and its performance remains to be determined and verified experimentally. However, there is a lack of test system that can fully meet the test requirements of Lamb wave gas sensor. In this paper, a test system...
Temperature has a considerable influence on the shallow water. Due to important economic value and relation to human activity, the on-line and real-time water temperature monitoring is of great scientific and practical significance. This paper has performed an experiment of a high frequency acoustic temperature measurement. Reciprocal sound transmission and the signal cross-correlation method were...
In the design of ultrasonic ranging system, MCS51 singleship is used as the core component of the hardware system and the control software is used. The software is designed with advanced microcontroller programming language. Closed loop control is used to adjust the amplitude of received signal and to extract the ultrasonic propagation time. The double closed loop control technique of amplitude and...
To estimate the mass emissions of combustion sources, the accurate determination of the exhaust mass flow with reasonable time resolution is a key requirement. State of the art flowmeters are often based on the measurement of the time of flight of ultrasonic bursts. Such systems are not well suited for harsh environment due to the fact that they expose their sensitive Piezo-transceiver directly to...
In this survey, in order to examine the viscous heating effect of thermocouples, temperature rise due to excitation of a HIFU transducer has been measured by using two different types of T-type thermocouples embedded inside the Tissue Mimicking Material (TMM). In order to obtain the temperature values from the thermocouples more effectively, a PC-based multi-channel data acquisition and monitoring...
This work presents a fully-printed metal-insulator-metal (MIM) thick film varactor capable of operation in matching circuits rated with up to 1 kW. The varactor utilizes a 20 μm thick layer of barium strontium titanate (BST) as tunable ferroelectric material. The design is based on a serial stack of capacitive MIM structures. The obtained overall capacitance is 1.9 nF with a maximum tunability of...
The article is devoted to the study of the existing methods and solutions of non-intrusive methods for flow parameters measurement. The literature sources with various types of measurement instruments used to measure the flow parameters were studied and reviewed. The theoretical materials on non-intrusive methods and device implementation examples are presented. The method for combination of the measurement...
This paper gives a method of ultrasonic heat meter design. Heat is calculated by measuring the flow and temperature of the water in pipe. Firstly, principle of ultrasonic is adopted to measure the flow of water in this project. Then, water temperature is measured by the temperature sensor in pairs of inlet and outlet. Finally, heat released through the heat exchange system is calculated by MCU. Inlet...
Aiming at the problem that the dual-frequency ultrasonic extraction of puerarin is difficult to detect effectively and efficiently with the method of manually watching and off-line detection, a method of soft sensor modeling is proposed. In the method, the genetic algorithm and the support vector machine (GA-SVM) are combined to build the soft measurement model of the puerarin extraction. By using...
This research mainly focuses on the household bean sprouts machines, putting forward a kind of intelligent photoelectric household bean sprouts machine, which is made up of the base, cover, cultivating cylinder, cultivating dish, pressure tray, pressure sensor, intelligent controller and control panel, etc. Considering that different beans need different illumination levels, this design uses the liquid...
Ultrasonic thermometry is a kind of emerging acoustic pyrometry technology, and it can break through the limitation of various electromagnetic environment, where the traditional temperature measurement methods have failed to operate satisfactorily. The temperature on the current path can be retrieved by the speed of the ultrasonic wave. When the measurement path is fixed, the key issue of ultrasonic...
This paper presents an ultrasonic thermometry state of the art study and shows principle of the ultrasonic thermometry through experiments with an ultrasonic thermometer prototype. The study covers a brief ultrasonic temperature measurement research history and focuses on recent revelations in this field. The thermometer prototype is constructed to be portable and usable for educational presentations...
In this paper, we find conditions that reconstruction of temperature distribution gets worse when the ultrasonic transceivers (transmitter and receiver) are arranged flexibly. We discovered the minimum number of the ultrasonic transceivers required for successful reconstruction and proved that the number is correct. Moreover, we proposed arrangement of the number in accordance with parity of pixel...
Electromagnetic [1] and acoustic [2] metamaterials that exhibit linear dispersion at a nonzero frequency and a wave vector (k) of zero, leading to a conical dispersion surface or so-called Dirac cone dispersion, have been demonstrated recently. These materials display unusual behavior associated with the occurrence of a finite group velocity at k = 0, leading to a wave which propagates with a uniform...
For new-generation thermal power plants, off-line non-destructive testing is not sufficient and long-term monitoring at high temperature is desired. In the previous study, ultrasonic transducers made by CaBi4Ti4O15 (CBT)/Pb(Zr, Ti)O3 (PZT) were investigated and maximum operation temperature was estimated as ∼600°C. Since operation temperature of new-generation thermal power plant will be ∼700°C, it...
Laser-generated focused ultrasound (LGFU) is a promising modality for micro-precision therapy, relying on cavitation-induced mechanical disturbance. However, conventional LGFU systems still require a high laser energy (several to tens of mJ/pulse), irradiated onto an optoacoustic lens, to generate a focal pressure sufficient for acoustic cavitation at focus. Acoustic attenuation over the tissue depth...
In many industrial technological processes, liquids are subjected to high pressures, e.g., in the high pressure food preservation. Similarly, in modern fuel injection systems for diesel engines, biofuel is subjected to a pressure up to 300 MPa. In such conditions, in liquids, high-pressure phase transitions (solidification) can occur that substantially increase the density and liquid viscosity. This...
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