Applied Mechanics and Materials Vols. 397-400

Abstract: Aiming at the practical problems existing in the fire disaster monitoring, such as harsh site conditions, the detection point difficult to change and expand, low automation level and the monitoring products having higher prices, etc., a fire disaster environment parameters intelligent monitoring system is designed based on the ZigBee CC2530 wireless communication chip. By deploying sensor network nodes in monitoring area, the monitoring information, that is, temperature, humidity, and smoke concentration of the fire site, is aggregated to the central monitoring system in order to achieve a unified data management and network routing monitoring functions. The central monitoring computer stores and displays the data sent by ZigBee network, thus the real-time monitoring of changes in environmental parameters of the fire site is achieved. The monitoring results have shown that this system is stable, high reliable in data transmission and easy to use, and can be used in environmental monitoring occasions inconvenient of direct attachment.

Abstract: Sampled fiber grating is a novel fiber Bragg grating. Because of it is flexible, passive, low insertion loss and small polarization dependent. It causes great interest and enthusiasm of the people in many areas. Ambient temperature and strain can both affect sampled grating reflection spectrum. On the base of analysis of sampled grating temperature and strain sensing model ,we can use computer to simulate the sampled grating temperature and strain sensing experiments to get Sampled grating temperature sensing data and strain sensing data. By analyzing the factors of temperature and strain which affect the spectral characteristics of the sampled grating, and using regression analysis methods to respectively get the 4 parameters A, B, C, D of sensing properties, so we can simultaneously measure the changes of temperature and strain through single sampled grating.

Abstract: A low cost novel integrated portable elasticity measurement system is developed by using strain gauges and photoconductive sensors on a coaxial movement mechanism for processing signal of force and displacement synchronously. Real-time acquisition data are averaged to reduce transmission delay for assuring signal taken exactly and synchronously. Switching circuit modules connected to the multiplexer are designed for processing nonlinear sensing data using a piecewise linear technology. An experimental study of force, displacement and elasticity is undertaken to illustrate the adjustment operation of tapping keys in alto saxophones. Experimental results show that the resolution and operation range of displacement and force are 0.1 mm in the range of 0 to 40 mm and 10 g in the range of 0 to 1000 g, respectively. The average error of the elasticity in real-time measurement is 2.07 %. The application of tapping keys adjustment using the system are outlined and discussed in three-zone elasticity models.

Abstract: An optical real-time pneumatic-and-centrifugal controlled microfluidic detection system for dynamic information acquisition is developed based on the quasi-stationary imaging technique. The programmable airflow applied on the centrifugal microstructures for improving efficiency in samples separation. The dynamic characteristic of a loaded disc is stable with vibrating under 0.3 mm at a speed of 1000 rpm by applying 3 bar-induced pneumatic forces on a 12 cm-diameter disc. A conversion model for converting RGB images into CIE L^*a^*b^* color space have been used to enhance the inspection images. A linear relationship between threshold frequency and sample density is 167 rpm/g/cm³. The pressures between 0.1 and 0.5 bars are applied to bias microflow from 15° to 80°. The conduction angles between 30° and 90° have better pneumatic control. The control efficiency observed up to 89% and the largest microflow biased angle reached 80°. The pneumatic force dominates microfluidic behaviors when the force is greater than 10 times the centrifugal force. A sequential of triple-reservoir tests has been verified by analyzing enhanced optical images in separation using arranged acid-base indicators for pH reactions.

Abstract: A collimator is one of the most popular optical instruments used in optical workshop and parallelism of the beams is the key technical indicator of collimator. A great deal of efforts has been expended to ensure reticle locate at the focal plane. In this paper, a new laser differential confocal collimator alignment method is proposed for precision alignment of collimators. Based on this principle an experimental setup is built up and used to align two collimators whose focal lengths are 600mm and 1000mm and f-numbers are both 10.The wave-front parallelism error of the laser differential confocal system and the tested collimator is measured by the verified experiment based on scanning penta prism method. At last some influence factors alignment precision is analyzed. Theoretical analysis and experimental results show that the alighment precision based on laser differential confocal method can reach to 0.004mm.and can be a high-efficiency approach to align collimators, especially in industry production.

Abstract: Relying on the author-designed new gas detector the system completes the ARM - based processor hardware platform software design, the using of smart home products design concept and the Internet of Things technology. The system had unattended receiving data, network remote query, data warning functions and with good prospects.

Abstract: In this paper, common parameters of wine are measured using attenuated total reflectance Fourier transform infrared spectrometer (ATR-FTIR). ATR cell is used which have the advantage of easy filling and cleaning. The parameters include sugar, alcohol, acid,, sugar-free extract, which is routinely measured in the wine quality determination. Commercial wines (n=125) both red and white were analyzed using the ATR-FTIR spectrometer. Reference data were measured based on standard procedure (GB150382006) and performed by technical analyst. Using PLS calibration method samples concentration can be predicted. The accuracy of quantification of main component such as total acidity, sugar, alcohol was excellent, with the measure error low than 1g/L. Some subdivision components are well, that concentration can be predicted in a lower accuracy. Based on the accuracy we obtained, the presented method can be used in winery widely as a fast method for measuring wines content.

Abstract: The disadvatages of traditional pattern of flue-cured tobacco are low work efficiency, high system error, and poor quality of tobacco and so on. In order to conquer the above shortcomings, a kind of monitoring system was designed in flue-cured tobacco barn based on ARM7 to implement the automation and intelligentization of flue-cured tobacco. The LPC2103 chip was chosen as the microprocessor of monitoring system. The data of temperature and humidity of barns was collected with the AM2303 sensor. We built the hardware platform based on embedded technology, and developed the corresponding software system for monitoring the control object of flue-cured barn in real-time, for implementing the automation of three stages flue-cured period which is yellowing stage, turning color stage and stem drying stage. The environmental data of flue-cured tobacco barn could be saved by the storage module .The result of testing experiments, which contain three periods of flue-cured tobacco, show that the features of our monitoring system ,which are nice control precision, lower system error, sooner response ,and good stability and so on, could be taken advantages of. The embedded technology of ARM7 could be used to improve the efficiency of flue-cured tobacco to guarantee the quality of tobacco, and cut the cost of labor, meanwhile, it could be applied to all kinds of flue-cured tobacco barns as well.

Abstract: A timing component is developed in order to achieve the synchronization between measuring system and external devices. The function of timing system, as well as the data switching driver based on twin port RAM and interrupt response driver developed by using DDK (Driver Development Kit), are introduced in this paper. The timing component has been used to ensure the synchronization between measurement system and vessel devices, and successfully applied in angular distortion measurement systems.

Abstract: Real-time measurement system possesses high real-time demand which multithreading technology can largely satisfy, because multithreading technology can implement many tasks at the same time and make largely use of the multiprocessor unique advantages. The paper adopts multithreading programming method to improve the real-time system and it achieves significant design effect.