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Due to mass paper images and large amounts of noise in a paper image for a on-line paper detection system, this paper presents a novel method of on-line paper defect detection based on Multirepresentatives Classification (MRC). First of all, using the background subtraction method is used to rapidly identify those papers with defects from mass on-line papers. Afterwards, pixels of paper defect images are clustered to segmentalize defect regions, and LOG operator is used for edge extraction. On the basis of these, characteristic value of paper defect are extracted. Finally 8 kinds of paper defects are classified by using multi-representatives classification, the classification complexity of which is O(n). The experimental results showed that the method could quickly and accurately classify 8 kinds of paper defects, thus the method can meet the requirement of on-line paper defect detection.

A novel molecularly imprinted polymer polypyrrole sensor for rapid direct tartrazine determination was established and is reported in this paper. Polypyrrole as a specific affinity molecule was immobilized on the surface of a glassy carbon electrode. It specifically bound to tartrazine quickly without sample pretreatment. Subsequently, the electrochemical signals were produced and measured accurately. The device possesses many advantages, such as high specific recognition properties, good chemical and mechanical stability, simplicity, low cost of preparation, and sensitive and label-free determination. A linear relationship between the current and the tartrazine concentration was observed from 1 to 10 nM, and a detection limit of 1 nM was achieved.

A novel biosensor (the synthetic receptor sensor) employing the molecular imprinted technology for the digoxin analysis is investigated. The molecularly imprinted polymer (MIP) modified electrode can specifically bind to the analyte in the sample without sample pretreatment. The digoxin analyzed by the MIP sensor was carried out in 1 mM K 3 Fe(CN) 6 solution with the cyclic voltammetry. In the system, the K 3 Fe(CN) 6 3− /Fe 2 (CN) 6 4− redox couple was taking place. When the solution contains the digoxin, the MIP on the electrode will bind the digoxin. Further the redox system is interrupted and the peak current is decreased according to the digoxin concentration increasing. Digoxin is a glycosylated steroid-like drug. It is important for the heart disease treatment. However, since the digoxin toxic level is low, the drug remains in the blood sample must be monitored frequently. The device possesses many advantages, such as high specific recognition properties, good chemical and mechanical stability, simplicity and low cost of preparation, sensitive and label free determination. The reproducibility is good (CV

In this study, a carbon electrode electroless polymerization of polypyrrole, which formed a layer of conductive film interface,then absorped a layer of carbon nanotube particles by the way of self-assembled, is studied. The modified electrode is used to electrostatic adherence of formaldehyde dehydrogenase, with Nafion solution capped. Moreover this paper discusses the work of electrode position, PH value and scanning speed on the influence of the electrode response, the response potential is -1.2v, the optimal PH value is 7.5, and we also review the linear range of this electrode, we discovered taht this biosensor have a good linear relationship with the concentration of 1ug/ml-360ug/ml, the Correlation coefficient is 0.9983. In addition,with the stability of this electrode tested, it can be stored 15d at4°C.

After analysing the Wiener process characteristics of reservoir storage capacity in flood regulation, an Ito stochastic differential equation including a random input term is proposed to describe and estimate the stochastic reservoir level hydrograph in a flood routing process. An expression of risk for flood release is given and the probability density functions of the reservoir level hydrograph, which are related to the risk of overtopping failure, are computed using a Fokker-Planck equation. Analysed and calculated results indicate that, by using the stochastic differential equations, the uncertainty influence of various random factors on the reservoir level hydrograph can be taken into account in the flood routing process. Therefore, the procedure of evaluating the risk of dam overtopping failure developed in this paper provides an improvement over existing methods.

A novel aptamer nano-porous silicon (PS) biosensor was investigated for the rapid determination of tetracyclines. Electrochemical impedance spectroscopy (EIS) was used to analyze the behavior of the sensor. The specific binding of tetracycline to the aptamer biosensor led to a decrease in impedance. The corresponding impedance spectra (Nyquist plots) were obtained when serial concentrations of tetracycline were added into the system. An equivalent electrical circuit was used to fit the impedance data. The linear range of the sensor was 2.1-62.4 nM.

Cavitation damage is often observed near the downstream end of the flip buckets of many high-head outlet works. To analyze and mitigate the problem, many research efforts now focus on the development of the boundary layer along the bucket surface. In this paper, the centrifugal-force effect on flow characteristics over a bucket is discussed. The boundary-layer momentum and energy integral equations are derived by incorporating the effect of the bucket curvature. The surface shear stresses are calculated based on the theory of wall layers. The turbulent boundary-layer thickness and the exponential velocity distribution are obtained by applying the finite-difference method. It was found that higher velocity occurs near the bucket surface throughout its entire length, and the skin-friction coefficient increases significantly in the downstream half of the bucket.