Advanced Materials Research Vols. 791-793

Abstract: At present, the water resources is increasing attention, water quality monitor and purify is widespread attention. The system uses sensors to monitor water, if the water contains excessive metal minerals or water turbid, the sampled data input SCM to process, MCU sends control signal, and motor start to work, pumping the water out and purify, and then monitor the purified water, if the water unqualified, and then purify again, until the water is qualified. The system also sets up a sound and light alarm and screen display, for prompting monitor information. The system is practical, it has guidance and reference for actual water quality monitor and purify.

Abstract: A reusable electrochemical biosensing strategy based on structure-switching hairpin probe for the detection of small molecules is proposed using cocaine as the model analyte. Aptamer probe hybridized with the immobilized signal probe to form DNA duplex. When target small molecule was added, competition between target molecule and the signal probe with the aptamer probe happened, which induced the signal probe from stretched duplex to hairpin structure. By measuring ac current voltammetry, the target molecule can be sensitively detected in a linear dynamic range from 1 nM-1000 nM with a low detection limit of 0.7 nM. In particular, the biosensor can be easily regenerated by melting in hot water, making it reusable.

Abstract: The vertical distribution of aerosol extinction coefficients within winter planetary boundary layer (WPBL) over the observation site are shown in this paper, and the heights of PBL are discussed. The data indicates that the aerosol over the measurement site is almost trapped within PBL and troposphere layer and is rather stable, and the multi-layer structure of the aerosol distribution is obvious.

Abstract: The excellent photophysical feature makes graphene widely applied in fluorescent sensors. Here, we summarize recent progress in the design of graphene-based sensors, especially the increase in the sensitivity of the detection of heavy metals. In addition, we also give an overview of the development of graphene-based sensors in the future.

Abstract: It is vitally important to improve effects of error compensation for horizontal photoelectric theodolite and reduce production costs by executing rational control of verticality error of shafting. This paper analyzes the mechanism how the verticality error of shafting influences measurement precision of photoelectric theodolite considering the architectural characteristics of the frame of horizontal theodolite. Matlab software has been used to simulate pointing accuracy. Verticality error of shafting of horizontal theodolite has been detected. Measured verticality error of shafting is 37 and detection error is 10. Results of analysis and detection to be applied for error compensation can improve pointing accuracy of the theodolite.

Abstract: Aiming at the purification of axis trace, a novel method was proposed by using ensemble empirical mode decomposition (EEMD). Ensemble empirical mode decomposition decomposed a complicated signal into a collection of intrinsic mode functions (IMFs). Then according to prior knowledge of rotating machinery, chose intrinsic mode function components and reconstructed the signal. Finally the purification of axis trace was obtained. Simulation and practical results show the advantage of ensemble empirical mode decomposition. This method also has simple algorithm and high calculating speed; it provides a new method for purification of axis trace.

Abstract: During drilling and tapping the deep holes of ratio of length to diameter of 6:1 to 10:1, the tools likely suffer random breakage, On account of such situation, a drilling overload protective system based on spindle power monitoring is raised. The analysis and processing of the abnormal signals detected by means of the principle of wavelet theory and real-time cross-correlation algorithm by detecting the loads and current of the machine spindle motor and changes of phase angles between voltage and current resulting in change of power, the shortcoming of hard determination of threshold function can be avoided while the sensitivity of signal can be guaranteed. The test results achieve the predicted effects with acquisition, processing and analysis numerous data.

Abstract: The paper presents a novel Si-substrated micro-hotplate for gas sensor. Use platinum filament as heater, SiO₂ as thermal and electricity insulation. Through optimizing analysis, in order to make the gas sensor obtain perfect properties of higher temperature and uniform temperature distribution, the thickness of SiO₂, thickness of Si substrate, electrode width and electrode space are designed to be 50, 250, 20 and 500 μm, respectively. Via the analysis of magnetic field distribution of the new gas sensor, the new electrode structure can eliminate the interference on the measurement signal from magnetic field, which is benefit for the improvement of sensor performance.

Abstract: An evaluation system of vehicle traveling state was proposed,and an unsafe vehicle traveling state recognition system was established using multi-level information fusion method. In view of the effects of the complexity of the driving environment, a variety of working conditions and the diversity of vehicle traveling characteristics, combing BP neural network with Dempster-Shafer evidence theory technique, the multi-information decision-level fusion was proposed to estimate the different kind model of the vehicle status. To verify the proposed strategies,the vehicle traveling posture evaluation system was established. The lane departure parameters and the relative distance parameters were studied in order to get the characterization of the vehicle traveling status information. The simulation results indicate that the adaptability and accuracy and the intelligence level of driving characterization estimation are significantly improved by using the pattern classification and decision technology of multi-source information fusion.

Abstract: In this paper, the proposed algorithm regards the human body object character symbol using Support Vector Machine (SVM) classifier to train and classify Histogram of Oriented Gradient (HOG) features, which improve the accuracy of human body detection. We use optical flow tracking algorithm based on corner points of the contour for tracking. Kalman filter is regarded as the predictor to predict the size and location of the searching object. Also, the size and location of track window is real-time updated. In this paper, we present an object tracking algorithm for multi-media teaching video shoot. Target tracking technology is used for the video image processing analysis. By extracting moving object, we can get information in the subsequent frames to determine the trajectory and size of moving objects. After analysis of a large number of experiments, we can draw the conclusion that the algorithm is effective.