Advanced Materials Research Vols. 301-303

Abstract: A novel crankshaft and camshaft measurement system by optoelectronic scanning of which a flat-crystal was used to generate high depth of parallelism scanning laser was implemented. The general structure and principle were given. Mass of test results showed that the system could achieve high precision. The ranges could achieve ±8μm, standard deviation could achieve 3μm, and easy to operate, work reliably, automatically and on line measurement could be implemented.

Abstract: Laser damage threshold of optical thin film is a critical parameter in measuring laser induced damage. The key to testing damage threshold is judging the injury incident accurately. It has been found that when high-energy laser on the film, there will be sounds generated. In the present paper, acoustic method was applied to determine thin films damage. A brief analysis will be given on feasibility of acoustic method in judging thin films damage. Acoustic acquisition system will be established. In the experiment, we will average laser energy into 10 grades, each grade test 10 points. The sound wave of each point will be record. At the same time, we use image method judge damage of the thin films and record the result. By studying the sound waves of the thin films in different laser energy，it is easy to judge whether the optical films is damaged. The measured result is compared with image method. Both of them have a preferable consistency. The analysis shows that the acoustic method can be used effectively to determine laser-induced damage and it can be used in online inspection conveniently.

Abstract: The virtual instruments utilize the powerful graphic environment and on-line help of computer to establish the virtual instrument panel and control the instrument, analyze and display the data, replace the traditional instruments and change their using modes, improve their functions and efficiency. This system utilized the virtual instruments technology, and PC/104 bus-based embedded data acquisition to develop the cable and harness test hardware system.

Abstract: As a link maintaining an interconnection relationship, the cable and harness are widely used for many fields such as electronic measurement, chemical industry, electric engineering, mineral exploration, medical treatment, vibration analysis, acoustic analysis, fault diagnosis and teaching & research etc, so the testing of cable and harness is very important. This system utilized Lab Windows/CVI as the core control software, developed the cable and harness test software system on the basis of hardware equipment. According to the different properties of testing parameters, respectively designed the corresponding test methods, through software setting, process and compare the data read-back, and determine whether the technical parameters of cable and harness are qualified or not according to the specified determination basis.

Abstract: In order to measure the flame height (L_f), the image processing method was employed. The jet flame image was captured by the common-used digital camera. The resolution (C, with the unit of mm/pixel) of the pixel of the digital camera was calibrated by metric scale. The jet flame image was then successively processed by ROI (region of interest) processing, gray processing, binarization and edge detection. Through the image processing, the pixels where the flame root and the flame tip were located was detected. The flame region expressed in pixels can be easily obtained by the difference between the flame root (X₁) and the flame tip(X₂). The flame height (L_f) was calculated by multiplying the difference in pixels (L_p= X₂-X₁) with the resolution of pixel (in millimetres per pixel). Using the proposed method, the flame heights of the pulverized coal jet flame at the high temperature air combustion condition were measured. The effect of experimental parameters on the flame heights of the coal jet flame was discussed.

Abstract: Scan chain design is a widely used design-for-testability (DFT) technique to improve test and diagnosis quality. However, failures on scan chain itself account for up to 30% of chip failures. To diagnose root causes of scan chain failures in a short period is vital to failure analysis process and yield improvements. As the conventional diagnosis process usually runs on the faulty free scan chain, scan chain faults may disable the diagnostic process, leaving large failure area to time-consuming failure analysis. In this paper, a SAT-based technique is proposed to generate patterns to diagnose scan chain faults. The proposed work can efficiently generate high quality diagnostic patterns to achieve high diagnosis resolution. Moreover, the computation overhead of proving equivalent faults is reduced. Experimental results on ISCAS’89 benchmark circuits show that the proposed method can reduce the number of diagnostic patterns while achieving high diagnosis resolution.

Abstract: This paper presents a Vernier Delay Line (VDL) for time interval measurement. A dedicated multiplexer is inserted into each stage of the proposed VDL. As a result, the D-flip-flops in each stage can be served as a large delay cell as well as a traditional arbiter. Moreover, the proposed interface circuit can save time residue out for further fine granularity measurement. Experimental results show that the proposed VDL achieves a 30ns measurement range with 6600 transistors.

Abstract: ECPR (electrically calibrated pyroelectric radiometer) is a kind of electrical substitution radiometer with high precision in detecting optical power. With the development of the enhanced UV ECPR, a measuring system for the absolute spectral response of UV detector is built. The paper introduces the measuring methods of UV absolute spectral response based on ECPR, the configuration of the measuring system and the measurement results. The feature of the system is high precision, easy operation and automation. Also it provides a good solution for the measurement of absolute spectral response of UV source.

Abstract: The FPN is an important part in CCD noise. The positions of the FPN in CCD are fixed, and the magnitude follows some rules. Through measuring the positions and magnitude of the FPN beforehand, we could eliminate the FPN in the image processing afterward. The causes and forms of the FPN are analyzed. The FPN of the science grad CCD Alta U9000 is introduced. The relationship between the FPN of U9000 and the exposure time is determined with the shutter closed. And the FPN of images taken in another experiment is eliminated. The experiment results well.

Abstract: The current oilfield monitor model in domestic is out of date which causes serious oil and facility stolen. Public security is not complete and efficient to prevent the crime. In order to solve this problem, Photoelectric Beam Detector has been adopt. This study utilizes Photoelectric Beam Detector, first transforming its information to electric signal and then with the help of Data Acquisition Module and GPRS technology, sending the message to monitoring and supervision center where possesses the security system software. The results indicate that it is an efficacious method to fulfill the security and pre-warning target.