Advanced Materials Research Vols. 694-697

Abstract: As overland oil exploration develops into the intermediate and advanced stage, more and more offshore oilfields have been exploited. However, due to various kinds of unknown factors on the sea, related operations are faced with enormous challenges. In view of the specific operating conditions, an underwater oil storage system with a storage liner was designed. Meanwhile, the leakage of oil was detected through an oil spill transducer based on optical fiber technology with in-time alarm. Moreover, detection signal was denoised using a threshold method base on wavelet transform. The results showed that the denoising method is simple to use, convenient and can effectively remove the noise.

Abstract: Due to the market demand for mobile, portable and remote heart electric monitoring system, the paper developed an Android ECG(Electrocardiogram) system based on the HL7(Health Level Seven) standard. Android phone as a gateway received ECG data via Bluetooth, and sent ECG message to the server by HL7 standard form. It explores the application of the Android phone in the field of mobile medicine.

Abstract: As fall is an accident being taken place ordinarily to the elderly, it is important to prevent fractures as a result of fall by detecting fall behavior in advance. The objective of this study is to distinguish activity of daily life (ADL) from fall by using wireless sensor module. This study intends to determine fall status before the body contacts ground surface after the fall starts. In this study, natural fall and acceleration being taken place during ADL were analyzed by using tri-axial accelerometer, tilt sensor and bluetooth module so that the body will not be bound at the time of fall. Test was performed on a soft mattress so that subjects will not be injured during the test process and fall was induced through rapid movement of mattress by using a pneumatic actuator. A sensor for detecting body movement was attached to the back and waist of the subject. Fall status was determined by using acceleration value being generated from the body and direction of fall was judged by angle value. As a result of the test, in case of using this system, fall status and its direction could be correctly detected.

Abstract: In order to ensure safety of wind turbine operation and to reduce the occurrence of faults as well as to improve the reliability of wind turbine operation, a vibration monitoring for wind turbine is developed. In this paper, it analyses the enlargement of all the parts of the structure and the working mechanism, the research method of wind turbine operation vibration is introduced, with the focus being the use of the sensor principle. Finally the hardware design and software of this system is introduced and the main function of this system is described, which realizes condition monitoring of the work state of wind turbines.

Abstract: Large cooling tower fan mainly used in petroleum, chemical, electric power industry, carries industrial water circulating cooling function and its operational status directly affects the industrial production. The blades are the important parts of the fan. The modal analysis is used to find the distribution of blade vibration frequency, and then the acquisition and analysis of vibration parameters of running large cooling tower fan blades are done using the EMD methods. Finally, compare with the modal analysis to find out safety hazards of fan blades. This method can eliminate the failures of the cooling tower fan blades, shorten the repair cycle, ensure the smooth production of the enterprise and improve economic efficiency.

Abstract: Coal and gas outburst is an extremely complex and serious gas dynamic phenomenon. Therefore, building an early warning system based on computer system, safety monitoring systems of coal mines and local area network is a precondition for effectively preventing coal and gas outburst. Combining the hardware conditions, organization management structures and characteristics of preventing outburst technology systems, this paper discusses the principle, logic structure and implementation process of gas outburst warning, devises the software and hardware structure of the warning system and therefore offers theoretical thought and methods for the forecasting of coal and gas outburst.

Abstract: In this paper, a novel fault diagnosis method for gear was approached based on morphological filter, ensemble empirical mode decomposition (EEMD), sample entropy and grey incidence. Firstly, in order to eliminate the influence of noises, the line structure element was selected for morphological filter to denoise the original signal. Secondly, denoised vibration signals were decomposed into a finite number of stationary intrinsic mode functions (IMF) and some containing the most dominant fault information were calculated the sample entropy. Finally, these sample entropies could serve as the feature vectors, the grey incidence of different gear vibration signals was calculated to identify the fault pattern and condition. Practical results show that this method can be used in gear fault diagnosis effectively.

Abstract: In this paper, a novel intelligent method to identify gear fault pattern was approached based on morphological filter, harmonic wavelet package and grey incidence. At first, the line structure element was selected for morphological filter to denoise the original signal. Secondly, different gear fault signals were decomposed into eight frequency bands by harmonic wavelet package in three levels; and energy distribution of each band was calculated. Finally, these energy distributions could serve as the feature vectors, the grey incidence of different gear vibration signals was calculated to identify the fault pattern and condition. Practical results show that this method can be used in gear fault diagnosis effectively.

Abstract: This paper presents a fault diagnosis method of roller bearings based on intrinsic mode function (IMF) kurtosis and support vector machine (SVM). In order to improve the performance of kurtosis under strong levels of background noise, the empirical mode decomposition (EMD) method is used to decompose the bearing vibration signals into a number of IMFs. The IMF kurtosis is then calculated because of its sensitivity of impulses caused by faults. Subsequently, the IMF kurtosis values are treated as fault feature vectors and input into SVM for fault classification. The experimental results show the effectiveness of the proposed approach in roller bearing fault diagnosis.

Abstract: The corrosion acoustic emission (AE) source location is one of the main purposes of acoustic emission testing (AET), corrosion detection and location can guarantee the safety and integrity of pipeline, storage tank and other equipment in the petrochemical industry. The computed source location and zonal location methods are reviewed in this paper, and also new source location method based on modal acoustic emission (MAE) is introduced and this new method will be more widely used in the field of corrosion detection in future.