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[en] Recently, since Engine Control Unit(ECU) trend to be high performance, which is to high integration and to thinness. Nondestructive test is generally performed to evaluate the reliability of ECU board with semiconductor packages. The test procedure is composed of c-scope of Scanning Acoustic Tomograph(SAT) method, in order to detect defects such as delamination and crack. In particular, contents of primary concern are delamination and crack caused by moisture absorbed under ambient conditions. we applied to polarity based image for detection of defects.
[en] This paper propose electronic speckle pattern interferometry(ESPI) for reliability evaluation of electronic device. Especially, vibration problem in a fan of air conditioner, motor of washing machine and etc. is important factor to design the devices. But, it is difficult to apply previous method, accelerometer to the devices with complex geometry. ESPI, non-contact measurement technique applies a commercial fan of air conditioner to vibration analysis. Vibration mode shapes, natural frequency and the range of the frequency are decided and compared with that of FEM analysis. In mechanical deign of new product, ESPI adds weak point of previous method to supply effective design information
[en] The angular dependence(profile) of backward radiated ultrasound was measured for glass specimens with random surface roughness using ultrasonic goniometer that ran changes the incident angle continuously. It was concluded that the roughened region had greater acoustic impedance than the unperturbed region. The comparison of backward radiations showed that the amplitude of peak and the area of radiation profile were increased with surface roughness. It was suggested from the sensitive dependence of the profile area that the profile of backward radiation could be applied to in the nondestructive evaluation of sulfate region. Inclined C-scan technique with the transducer inclined at Rayleigh angle showed the reverse of luminosity and the high signal to noise ratio so that it provided high resolution
[en] In the current economic environment, plants and facilities are under pressure to introduced cost saving as well as profit maximising measures. Among the many changes in the way things are run is a move towards Risk Based Inspection (RBI), with an emphasis on longer operating periods between shutdowns as well as to utilise components to their maximum capability. Underpinning and RBI program requires good data from an effective online inspections program, which would not require the shutdown of critical components. One methodology of online inspection is known as Non Intrusive Inspection (NII), an inspection philosophy with the objective of replacing internal inspection of a vessel by doing Non Destructive Testing (NDT) and inspections externally. To this end, a variety of advanced NDT techniques are needed to provide accurate online measurements. (Author)
[en] A global inspection equipment is developed to evaluate the status of component operations and function error, as well as having a comprehensive function board after examining the infrared components. Its basic principle is to analyze the measured power of the infrared rays each part emits at each instant. After applying the power and setting the initial conditioning signals to the board under test, tile system determines the normality of the parts and determines whether the board is working well. The normality is determined by comparing the change of infrared energy with tile reference patterns of the known good boards. The results of experimental test with several boards show that the system is accurate and reliable test solution and one of very useful methods to test PBA nondestructively.
[en] It has little possibility that cable causes any problem in transmission system. But when cable fault occurs, the damage is very severe. The main causes of the cable detections are bad cable making procedure, poor cable operation and deterioration according to the years. There are some cases to have potential problem due to many cable connection points, because of short length of cable, especially in 154 kV system. In this study, we propose new method to measure partial discharge in cable joints and probe the effectiveness of the method through experiment results.
[en] To get accurate information about the defect from the tested signal, NDT engineers should have a good knowledge on forward problems. Such knowledge is usually obtained by a lot of testing experiences. Another way of obtaining such knowledge is to build a database containing lots of defect information and their corresponding signals. However, archiving of raw test data would require a lot of disk space. In this paper, economic way of storing signals is studied by using fourier descriptors. Instead of saving raw data, fourier descriptors are saved within the error limits and this results in a saving in disk space. Of course, the defect signal can be reconstructed from the saved descriptors. By using differential ECT and RFECT signals produced by numerical modeling, the savings in disk space and the similarity of reconstructed signals and original signals are demonstrated. This Fourier descriptor approach could contribute significantly in building differential signal databases.
[en] We demonstrated a near-field scanning microwave microscope (NSMM) using a dielectric resonator which was appended a tuning fork for a tip-sample distance control. This NSMM system and a tuning fork shear-force method are working independently each other. The operational principle of NSMM system with a distance control was explained by the mechanical system of the damping harmonic oscillation and the material perturbation theory. We obtained both topographical and electromagnetic images of unspecified plant leaf.
[en] According to accelerating development of industry, it is needed to inspect industrial structure, safety of mechanical components and non-destructive testing. This paper is introduced to methods of inspection such as Holographic interferometry, digital shearography, electronic speckle pattern interferometry, Moire interferometry.
[en] To ensure the reliability of ultrasonic nondestructive testing techniques for modern structural materials, the effects of anisotropy and inhomogeneity and the influence of non-planar component geometries on ultrasonic wave propagation have to be taken into account. In this article, fundamentals and applications of two analytical approaches to three-dimensional elastic beam field calculation are presented. Results for both isotropic materials including curved interfaces and for anisotropic media like composites are presented, covering field profiles for various types of transducers and the modeling of time-dependent rf-signals