Papers by Keyword: Signal Acquisition

Abstract: The thickness of the plastic film is an important physical index to the production of plastic. The measurement reslut relates directly to the companies’ economic benefit. This paper mainly introduces the digital signal processing in the detection system of film thickness. Through a perfect processing, the system can improve its SNR and finally get a high precision. Firstly, the principle and scheme was presented. After that, this paper mainly introduces the hardware implementation of the system. It includes analog filter circuit, AD sampling and digital filter. With the experimental verification, the system realizes the measurement of the film thickness on-line which can get the precision of micrometer. At present, the equipment has aready put into use by some companies.

Abstract: Review of ultrasound applications in mechanical and material engineering is presented. Application examples in material thickness, profile measurement are given. Applications for load, stress, stiffness, porosity, density, viscosity, bond strength, hardening depth evaluation are discussed. Composite or polymer curing states can be monitored. Ultrasonic signal propagation velocity, attenuation or nonlinearity can be used for aforementioned parameters extraction. Signal acquisition setup configurations along with signal processing techniques are discussed. Ultrasound can be used for structure integrity testing or monitoring. Imaging of the inner material structure or properties distribution requires special reconstruction techniques. Presence of the structural noise is masking the defects. Image reconstruction and structural noise reduction techniques are outlined.

Abstract: There are various kinds of damage caused by large amount of harmonic in power grid. The research object of this paper is the harmonic in power grid. A simple and practical harmonic detection program is studied. And the harmonic analysis module is completed. First the principle of harmonic generation is analyzed. And then, the signals of the voltage and current in power grid are collecting. At last, the hardware and software of the module are designed. The signals are analyzed and calculated by the module. The harmonic content is put out. The test proved that the module has the advantages of high precision, good reliability and low cost. It can be used on a variety of equipment.

Abstract: In the technology field of world's high-speed Computer Numerical Control (CNC) communications, accelerating research for remote communications signal technology will not only promote the development of China's high-speed remote technology, but also has far-reaching scientific value, industrial and economic value to the train remote communications. The new train remote communication technology is the basic topic with high technology, which has complicated procedures, in fact, contains mixture and summary of multi-skills, such as the compute control, application of sensor technology, the recognition of test skills and digital signal processing, and aggregation. Therefore, it can improve signal collection efficiency, and access to dynamic unbalance signal of the train remote communication signal.

Abstract: This paper study the wind turbine bearing vibration signal characterization and nonlinear transient characteristics, the transient signal characteristics were established based on Wigner-Ville spectrum entropy and support vector machine (SVM) extraction and fault diagnosis model and quantitative description of nonlinear characteristics of multi-scale method based on LMD sort of entropy, and the effectiveness of dynamic signal feature extraction and fault diagnosis method of the study, a typical experiment platform bearing bearing fault diagnosis experiment verified.

Abstract: This paper presents fuzzy color histogram feature-based image retrieval method and texture spectrum fuzzy histogram feature analyzes the image database indexing techniques and the introduction of the experimental system for an improved method of fuzzy indexes. Algorithm reflects the underlying characteristics of high-level concepts and integration, relevance feedback and machine learning mechanism combining ideas. In this paper, the algorithm full processing power of computer systems, has a certain reference value and practical significance.

Abstract: On-line monitoring of tool wear in turning is vital to increase machine utilization as scrapped components, machine tool breakage and unscheduled downtime result from worn tool usage cause huge economic loss. Several techniques have been developed for monitoring wear levels on the cutting tool on-line. Keeping in to account the difficulties encountered during the implementation of tool condition monitoring (TCM). The signal acquisition is one of the key elements used during the implementation of TCM. This paper provides an in depth coverage of various signal acquisition methods used in TCM.

Abstract: The paper proposes an improved genetic algorithm which is applied to the problem of GPS signal acquisition.The improved genetic algorithm uses the small section method of the initial population, dynamic search range of parameter, and the adaptive crossover probability and mutation probability to search GPS signal parameters. Simulations and experiment results show that the improved genetic algorithm can search the signal parameters rapidly and precisely. The GPS signal acquisition performance is improved.

Abstract: Electro-hydraulic control system of hydraulic support in addition to being able to control the basic movements of hydraulic support, also can work for signal acquisition of mining environment, including pressure of column pressure, displacement of push lutetium and pull support etc. The electro-hydraulic control system is presented in this paper, on the basis of the original control function added signal acquisition module, and designed the hardware and software.

Abstract: This paper introduces one method to design a vibration diagnosis device from several sides such as components choosing, circuit designing and soft programming. This device consists of ATmega128 MCU, acceleration transducer, TLC2543 and other peripheral components and it can conveniently acquire and analysis signal. The resource used to test the device was supported by Function Generator and amplified by Power Amplifier. The data was exported to PC and graphed by MatLAB application, and then made a comparison with the theoretical graph to prove the method validity. This design has simple circuit and small codes, but it can capture mechanical working state accurately, so it has preferably practical value and economic benefit.