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981.
982.
In this paper, a novel multidimensional scaling (MDS) based on information measures method is proposed to analyze financial stock markets. In order to examine the effectiveness of this method, we applied it to the classification of two types of artificial series, the logistic map model and the cubic map model, as well as stock time series. Moreover, the traditional MDS using Euclidean dissimilarity is also provided as a reference for comparisons. The results show that the MDS based on information measures can give us more detailed, exact and clearer information on the classification of simulation series and stock time series than the MDS using Euclidean dissimilarity. In addition, the proposed graphical method may also assist in the construction of multivariate econometric models.  相似文献   
983.
984.
985.
986.
This paper describes the electrocatalytic oxidation of amines on TEMPO (2,2,6,6‐tetramethylpiperidine‐1‐oxyl)‐modified electrodes prepared by electrochemical copolymerization of TEMPO precursor containing pyrrole side chain and 2,2′‐bithiophene. The modified electrode exhibits electrocatalytic activity for the oxidation of primary and secondary amines. Cyclic voltammetric studies showed that the peak current of the cyclic voltammogram increased linearly with increasing concentration of amine in the sample solution.  相似文献   
987.
988.
This paper presents fuzzy acoustic emission identification in high precision hard turning process based on extended subtractive cluster analysis combined with the least-square estimation method. The fuzzy identification method provides a simple way to arrive at a definite conclusion based upon the information obtained with the difficulty in understanding the exact physics of the machining process. The experimental results prove that the proposed method is efficient and feasible.  相似文献   
989.
Chemistry and physics of thin semiconducting layers of various types are subjects of intense research. Especially when nanotechnology methods such as self-assembly are involved, amazing structural and/or functional properties may appear. Also modern physical methods using variously organized plasma arrangements are able to produce uniform structures with distinctive functionality. In this review, based virtually on our own work, discussions on the preparation, structure, morphology, and function of titanium(IV) oxide nanoscopic thin films are presented. It was shown that structurally and functionally similar titanium(IV) oxide films can be prepared via completely different preparation techniques. Function tests were arranged as “primary”, covering the assessment of the light induced charge separation efficiency, and “secondary”, based on photocatalytic surface oxidations.  相似文献   
990.
A short-term aerobic stabilization of digested waste in the final methane phase was studied. The effect of aeration rate on the reduction of leachate parameters and on the rate of CO2 production and O2 assimilation was investigated. Experimental simulation of aerobic landfill stabilization was carried out using lysimeters. When testing the effect of aeration rate on the reduction of leachate indices (BOD5, COD, N-NH4+), it was reported that the most significant reduction was obtained at the highest rate of aeration and the smallest reduction of leachate indices was attained not at the lowest but at medium aeration rates. Both the rate of CO2 production and the O2 assimilation reached their highest values in the lysimeters aerated at a high rate of aeration. The proposed mathematical model which consists of a system of five differential equations describing CO2 production, O2 assimilation and the changes of organic carbon content in the leachate correspond well with the experimental data.  相似文献   
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