Advanced Materials Research Vols. 706-708

Abstract: In this paper, after the simple and practical hardware is connected with the host, the software system is used to count the colony of bacteria, the results are statistically analyzed, and the obtained data can be displayed, saved and printed. The software is developed with VC++, using digital image processing knowledge to do some research on automatic analyzing the count of colony.

Abstract: Biomechanics is a relatively new discipline where engineering and mechanics principles are applied to the understanding of biological organism. Biomechanics simply taking place to study the mechanics of tissues, joints, human movements, circulatory system and digestive tract. One of the most challenging applications of biomechanics is in the field of sports and sports medicine in which the prevention of sports injuries is highly required. To understand and to diagnosis tissues abnormalities, mechanics of neuromuscular control, mechanics of cardiovascular function, a synchronizing interface with multi biomechanics sensors is developed in this effort. The interface shows different data recorded from several sensors during a physical activity made by the subject. These synchronized and combined data will help the user to make a specific diagnosis of the subject health. Moreover, these data will give an insight understanding on the correlation between variety aspects of biomechanics.

Abstract: In this paper, the development of the amplitude-frequency characteristic tester based on SCM control has been introduced. The digital frequency synthesizer has been adopted to generate the automatic sweep frequency sine signals so as to provide the reliable sources for the frequency characteristic tester. The amplitude and the frequency characteristics of the active network and the passive network can be obtained through changing the output signals of circuit measuring network by digital analogy as well as the operation program of the microcontroller under the input signals with different frequencies. In this paper, the working principles of tester, the software and hardware design for the frequency synthesizer signals, the hardware and software design of the data collection channels and the applications of LCD technology have been specially discussed.

Abstract: With of the increasing application of high tech and information technology, wireless sensor network has already become one of the hottest topics. The SmartNet is to build an intelligent home network system. In SmartNet, the format of control string, the interpretation structure of driver, and the network manager protocol were designed. And the design can be divided into two parts: software and hardware. The hardware is mainly defines rules, while the software part is mainly interpret the driver of hardware, generate user interface of the device, and organize and send commands.

Abstract: Wavelet transform algorithm with its unique multi-resolution analysis and it is in the time - frequency domain has the advantage of the ability to characterize the local signal characteristics, let it has been widely used in signal detection, noise removal, feature extraction, image compression and so on. In this paper, on the basis of already wavelet transform ECG noise removal, proposed a median filter optimization algorithm, enables ECG noise removal effect is more obvious, also for the Eigen values detection of ECG lay a better foundation.

Abstract: tructural health monitoring based on piezoelectric technology has the features that are sensitive to early damage, insensitive to the environment, low cost and suitable for monitoring on-line. It has received more and more attention. In this thesis, the actualities of Impedance-based structural health monitoring are introduced for future reference.

Abstract: In order to improve acquisition speed and carrier frequency accuracy, a fast algorithm to acquire GPS signal is proposed. Signal-to-Noise Ratio is improved by coherent integration and non-coherent integration. The advantages of serial sliding algorithm and circular correlation algorithm are combined to achieve high carrier frequency accuracy. Removing the information of C/A code makes serial search from two-dimensional to one-dimensional to achieve less computation. Simulation shows weak signal of-30dB S/N is successfully acquired. The error of carrier frequency is controlled within 50Hz. So the data processing efficiency for the tracking loop is greatly increased.

Abstract: According the characteristics of rolling bearing fault information are nonlinear and non-stationary, the method of time-frequency is often used to make the one dimensional time signal map into two dimensional time and frequency function, and describe the energy density of signal at different times and frequency simultaneously. A method of fault diagnosis based on S transformation and image Hu of invariant moments was put forward in this paper. First of all the measured rolling bearing signals have been S transformed, and time-frequency spectrum which is got is expressed as two dimensional image, then Hu geometric moment invariant of the S transformation spectrum is calculated and the simulation research is carried out using invariant moment principle in image processing. The results show that this method can distinguish the inner ring, outer ring and bearing roller fault intuitively and accurately and measure rolling bearing fault diagnosis efficiently.

Abstract: The bearing of rotating machinery often fails due to the frictional forces of rolling element, in the early stages of the faults, a series of ultrasound can be generated in short time intervals, which occur at bearing characteristic frequencies. Since the frequencies of ultrasonic signal are very high, they will lead to much higher computing burden when using the common technique of Fast Fourier Transforms (FFT) directly. In this paper, envelope detection technology and heterodyne technology which integrated in an ultrasonic data collection system are used to reduce the frequency effectively. To allow for the easier detection of the bearing faults, these two techniques has been used together with FFT. A verification research with respect to vibration analysis is carried out to analyze the effectiveness and superiority of ultrasonic data collection in time domain and frequency domain aspects respectively. Extensive experiments have been performed in an Alternating Current (AC) motor system, and the results indicated that this ultrasonic data collection system is as useful as vibration analysis system in diagnosing the faults of bearings. In addition, it is more sensitive in fault diagnosis in the early stages of the bearing faults than vibration acquisition system.

Abstract: More and more research works have been focused on the quadruped walking robot because of its flexibility for the dangerous and complex environment. The Straight and turning gaits of a quadruped robot (JQRI00) were planned by the principle of stability margin. The virtual prototype model of the JQRI00 was constructed, and the results of the simulation and analysis of the designed gaits using ADAMS simulation software indicate that the straight and turning gaits are feasible. Moreover, the S-curve used as displacement control makes the robot more stable.