Applied Mechanics and Materials Vols. 635-637

Abstract: This paper researched the failure mechanism of the gearbox and resample algorithm in order analysis. For diagnosing the types of gearbox’s fault by analyzing the acquisition of vibration signal and extracting the fault characteristics of the gear. A function that relation gearbox vibration signal amplitude to order and shaft speed and transform from the time domain signal to angular domain signal was deduced. The MQ250 gearbox model was applied for the experimental analysis in this paper, the fault mechanism function of this gearbox has been successfully verified and the gearbox fault characteristic information has been extracted.

Abstract: The monitoring and fault diagnosis system for controllable pitch propeller is based on modern testing technology, fieldbus technology, monitoring and diagnosis technology, computer technology. The equipment consists of various types of sensors, CANopen bus devices, LabVIEW and computer, which can monitor the CPP’s operating parameters, including shaft system vibration, shaft speed, pitch angle, liquid level of gravity tank, pressure and temperature of hydraulic system, and the system can also alarm if three typical fault of shafting occurs.

Abstract: A novel in-line fiber temperature sensor by splicing a piece of single mode fiber between two thermally expanded core fibers at their core-expanded ends is proposed and demonstrated. This structure forms an all fiber Mach–Zehnder interferometer due to the interference between the core mode and the cladding modes of the single mode fiber. The fabricated sensor is applied to measure temperature changes. The temperature sensitivity of the sensor at a length of 6.3cm is about 65.3 pm/°C. The proposed sensor is low cost, easily fabricated, and may be useful for detection of temperature.

Abstract: A data communication method applicable to building detection industry based on the wireless sensor network (WSN) is designed and implemented in this paper, in which the cause of data loss is analyzed in accordance with the characteristics of wireless sensor network and that of building detection industry. Besides, relevant data storage protocol, staggered transmission protocol, and real-time data replenish protocol are formulated to solve the problem above and improve the reliability and integrity of data.

Abstract: Safety and reliability are the key of the smart substation, which requires the transmission of sampled measurement values (SMV) is in real-time and accuracy. Therefore this paper analyzes all aspects of SMV delay. The model is set up and the method of phase compensation delay is put forward through analyzing, and an engineering example is given. The conclusion shows that the algorithm can reduce the phase error of SMV and improve the real-time performance of SMV transmission.

Abstract: To detect the assembly quality of combine harvester, vibration spectra analysis method based software was proposed using the advanced graphical language LabWindows/CVI. Each spectrum band of different features was acquired by extracting special features of the vibration signals from some main rotary tillage parts. Using the six bands analysis method to judge whether the assembling of combine harvester was qualified or not by comparing the features with alarm windows established before. A serial of tests showed the software could correctly calculate the peak value and spectra energy for the divided spectrum. Furthermore, by comparing with the assembly quality feature database, the software could provide diagnose of assembly quality for a combine harvester rapidly.

Abstract: The purpose of this study is to compare the reliability of Likert scale between crisp and fuzzy data. The survey data is simulated based on two kinds of questionnaire data. They are questionnaire of crisp data and fuzzy data respectively. According to the viewpoints of fuzzy logic, human thinking is multi-value and fuzzy data will be more appropriate for survey. Therefore, it is proposed that the reliability from fuzzy data will be higher. Results of the simulation show that reliability of fuzzy data performs better than crisp data. Based on the findings of this study, some suggestions and recommendations are discussed for future research.

Abstract: Privacy preserving plays an important role in application of the Internet of Things (IoT). As apart of the IT, Wireless Sensor Networks (WSNs) should provide the privacy preserving in data aggregation. This paper presents a novel energy-saving private-preserving aggregation scheme (ESPART) for Wireless Sensor Networks, which uses characteristic of the data aggregation tree structure to reduce communication overhead. It assigns the random time pieces to nodes with aim to avoid collision, and limits the scope of collusion data to reinforce data—loss resilience. Compared with the SMART algorithm have less communication overhead. ESPART uses data-dependent fusion characteristics of the tree structure to eliminate SMART algorithm for unnecessary communication node, so that in case of the same privacy protection security, the data transmission amount is reduced to about 48% of SMART.

Abstract: Cutting force is one of important parameters for manufacturing processes. The traditional dynamometer is limited by size, machining environments, and so on. This paper introduces a new constantan thin film sensor which embedded on the holder of external turning tool to measure cutting force. The relationship between force and output voltage are deduced from theory. By using the finite element software, the analyses on induction and linearity capability of thin film sensor are simulated, and the influences of the location and thickness of film on the output voltage are analyzed. The results show that the linearity of input and output is good and the deviation between the calculated value and simulation results is identical. As the result, the constantan thin film sensor unit can be used to measure the cutting forces.

Abstract: To monitor the concentration of CO accurately and in real-time in the environment with flammable , explosive and toxic gas, the intrinsic safety CO monitor with low power consumption was designed by using the low power consumption technology and intrinsic safety technology. The feasibility of the intrinsic safety design was verified by the electric spark discharge calculation and heating calculation. Low power experiments verified the low consumption characteristic of the CO monitor. This method can also be extended to the system to monitor other poisonous and harmful gases.