Advanced Materials Research Vols. 718-720

Abstract: This paper presents a non-contact measurement solution, which can be used for rapid and accurate measurement of machinery and equipment in a variety of transmission gear wear or breakage situation. This scheme is based on machine vision technology. Through the reverse engineering method we re-build the three-dimensional model of gear s from their two-dimensional image, which can make all the wear and damage morphology of gear surface comprehensively and accurately reappeared. At the same time we give a characterization of the relevant parameters of the wear and tear. Therefore, this method could solve the difficulty in terms of gear wear detection, such as operability, uncertainty and other issues. The application of this method can also provide accurate gear wear data to predict the service life and provide the essential date for the maintenance decision.

Abstract: The detection of through-hole with a diameter of 1.6mm and the consistency of its signal are the basic evaluation indicators to decide whether the drill pipe is available. The relative position of the defect and sensor is random during the actual detection, causing the difficulty that it is hard to ensure the signal consistency of through-hole detection. This paper begins with the analytical model of magnetic field leakage (MFL) for through-hole, using the coil to detect the tangential component of the through-hole MFL, with the single sensors signal shown by simulation. Experiments and numerical simulation were done for the 1.6mm through-hole to acquire the effective coverage of its MFL and the suitable spacing of array sensors. The experimental results are consistent with simulation, which could be theoretical guidance for the optimization of array sensors.

Abstract: Based on a brief introduction of the operational principle of terrestrial 3D LiDar, this paper describes some typical defects detection methods of security distance in the overhead transmission line with living examples. These tests are realized by the Z+F Imager 5010 terrestrial 3D LiDar and Polyworks. The research results show that terrestrial LiDar technology can achieve the defect evaluation of defect detection of security distance in the overhead transmission lines. And this technology has many advantages, such as portable, security, intuitive and high precision.

Abstract: t would be a large effort to use traditional methods of calibration procedures for Web Offset Press equipments. In this paper we proposed a convenient process calibration, which will not only guarantee the product quality meeting the ISO standards, but also save financial and material resources. Firstly, the measurements for determining the best ink thickness in Web Offset Press are discussed. The chromaticity values on solid fields with corresponding combination of paper and ink required by ISO Standards were achieved. Through a optimization process for gray balance, the printed tone values were adjusted to meet the requirements of ISO Standards. Finally several standardized test targets on sampled sheets ware measured, then the ICC profiles were created. This paper proposed an innovative process calibration, therefor using methods of chromaticity measurement, characterization of Web Offset Press can be put to effect to optimize printing processes.

Abstract: In this paper, common heat-set web offset printing materials, paper and ink were tested based on ISO standards. We analyzed the datum of paper and ink to see the degree of compliance with the ISO standards,thus obtained the characteristics of the commonly used paper and ink in China in terms of their response to the color.The purpose of the analysis is to provide a reference for the implementation and controlling of enterprise printing standardization process.

Abstract: A new method on fault diagnosis for gear based on ensemble empirical mode decomposition and slice bi-spectrum is proposed. Firstly, fault signal was decomposed into a series of intrinsic mode function components of different frequency bands by EEMD, and then calculated the envelope signal of IMF component by Hilbert demodulation method. Finally, analyzed the envelope signal by slice bi-spectrum and extracted the fault characteristic frequency. The anti-alias decomposition capacity of EEMD and capabilities of noise suppression and non-quadratic phase coupling harmonic components elimination of slice bi-spectrum were verified by analyzing the simulation signal. The analysis results of gear pitting failure signal and gear wear fault signal showed that this method could judge gear fault type accurately and has a certainly degree reliability.

Abstract: Using portable emission measurement system, an experimental study on the NOx emission characteristics of city bus in practical operation are conducted, the eigenvalue of driving cycle are analyzed by short trip method. The results show that: idling time accounted for 20.392%, ratio of acceleration which between-0.5 m/s² and 0.5 m/s² accounted for as high as 83.314%.NOx emissions are greatly affected by the speed of vehicle: the instantaneous rate and total amount of NOx emission under high speed are much higher than low speed, the average urea injection under high speed is 3.5 times than low speed. When the vehicle speed is between 20-25km/h, the average emission rate of NOx is about 0.074g/s,while the time proportion of urea injection is under 40%;while the vehicle speed is above 55km/h, the average emission rate of NOx is about 0.025g/s,while the time proportion of urea injection can reach as high as 80%.

Abstract: The paper briefly reviews the operational principles and commercialized conditions of airborne three-dimensional (3D) LiDar and terrestrial 3D LiDar. And then the representative functions of 3D LiDar that are developed for the operation and maintenance of overhead transmission lines (OTL) are described in detail. Besides, the problems associated with the process of applying 3D LiDar to OTL are analyzed. It is pointed out that it is necessary to make improvement to several aspects, including new functions development, standardization of application approaches and the simplification of data processing.

Abstract: In this paper, a condition monitoring system for wind turbine drive train is developed. The system integrated multiple type sensors such as vibration, voltage, current, speed, temperature and multimedia to monitor the condition of gearbox. This system is designed to monitor all wind turbine drive train in a wind farm using distributed processors to avoid computational and communication problems. The experiments on a wind farm in north china proved that the system is reliable and valid on abnormal condition detection for wind farm drive train.

Abstract: In a kind of large test system, the whole equipment is constituted of many multiple subsystems. These subsystems become one by the interconnection. During the measuring and calibrating procedure for the test system at the outdoor training venue, many low-voltage DC signal the need to be measured at very high precision. The signal being measured were often found instability caused by the interference from various kinds of factors in the actual measurement, In order to ensure accuracy of measuring data and credible for results, to provide practical and reliable data reference for the effectiveness of the equipment system, we must analyze the causes of interference and to take effective measures targeted respectively.