Applied Mechanics and Materials Vols. 241-244

Abstract: In view of the difficulty to operate, low efficiency, and easy to leak of the manual perfusion method for dissolving cholecystolithiasis, an automatically perfusion-dissolved instrument is designed. By means of collecting and analysing the pressure data being outputted from pressure sensor in real time, and adjusting speed and direction of peristaltic pumps automatically to control quantity of dissolvent, so as to achieve the goal of litholysis under constant pressure in the gallbladder. The instrument has function of automatic heating and controlling temperature. Double controllers are used in the design, slave computer controls the running of each module of the instrument, and master computer is used to real-time display operation state and set parameters. Experimental results indicate that the system is stable and reliable, and with high efficiency for dissolving cholecystolithiasis, which provides a new and effective method for cholelithiasis medical treatment.

Abstract: Aiming at development and requirement of environmental monitoring, automatic weather station (AWS) must be more powerful and reliable. With distributed data acquisition nodes, new AWS extends and adds new sensors easily. Using protective power supply to each node, new system has high performance of lightning protection, which will not let system breakdown for any node crash. Three-stage automatic self-checking for node state is included, which makes failure diagnosis efficient. Data quality checking node is created in the new design. By databases and correlation models, it provides data self-checking functions for unattended AWS. Defects of old design such as fixed hardware configuration and centralized data acquisition are overcome. Flexibility and stability of AWS are improved, and data reliability of unattended AWS is improved.

Abstract: A time-division dual-frequency excitation scheme was proposed as an improvement to the traditional electromagnetic flowmeters. The proposed scheme keeps the advantage of zero-point stability of the traditional design, the immunity to low frequency noise is enhanced, and the response to fast change of fluid velocity is improved. A prototype flowmeter was made based on the proposed design, experiment results show that the prototype flowmeter can measure water flow in a wide velocity range with satisfactory accuracy.

Abstract: For a regular Digital Peak Respiratory Flow Metter, a strain gauge or similar probe is used to detect the strength of the blowing. The signal is then be analyzed by computer. In this innovative Self-Power Peek Respiratory Flow Meter, however, a generator is used. The generator is “one stone for two birds”: it serves as the digital signal generator to present the air flow data; it also provides the energy source to re-power the batteries. This allows people to use the equipment whenever and anywhere without worry of recharge or change batteries. Another advantage of the machine is its reliability. The blowing chamber is separated from the generator by magnetic (shaft-less) coupling, therefore, the moisture from blowing has no way to corrode the electric circuit or contaminate the instrument. Because of this innovative instrument is “Green”, “Digital” and easy of use, the application would be expanded. The Coreless Permanent Magnet Disk Generator technology (AFPM) is utilized to eliminate the cogging torque. Moreover, energy saving circuit design also implemented to make the self-power instrument a reality.

Abstract: Design of LCD(liquid crystal display) screen system based on DSP has been put forward. There are two parts of the hardware interface circuit and the software design about whole system. Chinese characters, characters and graphics can be displayed in the LCD system. The result of simulation shows that the system can effectively solve the drive and display of LCD based on DSP and can save resources for I /O port. This design will offers a certain reference value for a variety of display terminal design of the portable system. The simulation shows that the system can realize the basic expected goal.

Abstract: Electrostatic detection is remarkably developed and has been employed to detect human activity for years. In this paper, an induction electrostatic detector is designed, and used to measure human walking signals. The gait signals of totally six segments of the same object are measured in the experiment. An algorithm is proposed to obtain accurate gait cycle. The original signals are transformed to correlation coefficient series. Peaks of correlation coefficient series is picked out as the same phase point instead of peaks of walking signal. The time between very second peaks is defined as gait cycle of object. Based on the gait cycle, we discussed the recurrence property as the characteristics of human beings. It is expected that the slope of the recurrence line can be used as an index, and will indicate the personal particularity of objects in detection and their physical conditions.

Abstract: Life Cycle Cost (LCC) Management is not only an advanced management concept but also an effective way to achieve the integration of high-efficacy and low-cost assets. In the meantime, the State Grid Corporation promotes the “Large Five” system that novel environment provides new opportunities and challenges to the life cycle cost management. Therefore, this paper puts forward a transformer cycle cost model which adapts to the new environment, combining with new features of the “Large Five” system construction, basing on the whole life cycle cost theory and according to the actual operation of the transformer. It also analyzes the cost composition of transformer’s life cycle and verifies the validity of the transformer cycle cost model which has been put forward in this paper through calculating examples.

Abstract: UWB technique is widely used in radar detection system benefiting from the large bandwidth and short duration of UWB pulses. In traditional detection system, correlation receivers are usually adopted since lower SNRs are tolerated. This paper analyses the performance of anti-interference with 30dB additive noise for reference signal and 20dB additive noise for received signal as well as the pulse position shift of 100ps in UWB correlation receivers.

Abstract: A low-cost sustainer with a simple energy recovery (ER) circuit for plasma display is proposed in this paper. The proposed ER circuit employs a bidirectional switch consisting of one switch and four diodes. In the proposed sustainer, the insulated gate bipolar transistor (IGBT) can be used as a switch. Since all power switches are turned off under zero-current switching (ZCS), the tail current problem associated with IGBT does not occur in the proposed sustainer. Theoretical analysis and performance of the proposed ER circuit were verified on an experimental prototype operating at 200 kHz switching frequency.

Abstract: The analysis of charge circuit and discharge circuit is a key part in the theoretical study of electromagnetic riveting electromagnetic field. Numerical simulation was used to establish the charge circuit model and the discharge circuit model which was an electric circuit-magnetic circuit coupling process by ANSYS. The simulation of charge circuit shows that the development of the charge current over time is an exponential descending change and that of the charge voltage over time is an exponential ascending change. And, the simulation of discharge circuit indicates that the driver is mainly subjected to axial magnetic force, whose distribution is non-uniform along the radial direction of driver, and the maximum value of axial magnetic force locates in about half of the driver radius.