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1

Study on Adaptive Threshold Segmentation Method Based on Brightness

Zhao D., Dai X., Sun G., Lu T.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 9b

150-152

EN

Image segmentation is one of the most important steps before the image data analysis, which divided the image into several areas that have strong similarity. With the more and more widely application of the mesh fabric, the quality requirements are more stringent. As the impact of uneven illumination, the image brightness is inconsistent, which bring a great difficulty to the image segmentation of the mesh fabric. In order to eliminate the effect of uneven illumination in the image acquisition of linear CCD camera, the adaptive threshold segmentation method based on brightness is proposed. Compared with the Otsu method, it is better to eliminate the influence of the uneven illumination and provide a good foundation for subsequent data analysis.

PL

Analizowano system segmentacji obrazu polegający na podziale obrazu na obszary o dużym podobieństwie. Przy nierównym naświetleniu powstaje problem segmentacji. Zaproponowano adaptacyjny system progowej segmentacji bazujący na analizie jasności.

2

Lu T., Ma K., Zhang Y., Ni H., Fu B.

Polish Journal of Ecology

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2009

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Vol. 57, nr 4

647-657

EN

Disturbance is considered to be one of the main factors influencing variations in species diversity. While many experimental and observational studies provide a good understanding of how disturbance maintains the [alfa]-diversity, we know little about how disturbance influences [beta]-diversity, and the effects of disturbance intensity on spatial species turnover are lacking. The aim of this paper is to evaluate the effects of disturbance on patterns of species similarity in wetland communities, and to identify how disturbance intensity affects the species similarity - distance relationship. In our study, four isolated wetland remnants under different agricultural drainage ditch densities were surveyed in Sanjiang Plain, Northeast China. Wetland disturbance was assessed by agricultural ditch densities, and species similarity was quantified by the Jaccard index. A simple measure of environmental distance was obtained by using water level and five soil variables, and a corresponding measure of geographical distance was made between pairs of plots from each site. Based on these data, we estimated rates of distance decay through regression of log-transformed compositional similarity against both environmental and geographical distance for pair-wise comparisons of wetland plots from each site. One key finding of our research is that disturbance intensity does influence the species similarity - distance relationship. At each site, species similarity decreased significantly with distance, and both effects of geographical and environmental distance were statistically significant. The results indicate that with disturbance intensity increasing, the distance decay rate decreases.

3

Diversity and composition of wetland communities along an agricultural drainage ditch density gradient

Lu T., Ma K., Fu B., Zhang J., LU Q., Hudson S.

Polish Journal of Ecology

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2009

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Vol. 57, nr 1

113-123

EN

Agricultural drainage ditches are a reflection of the disturbance caused by agriculture and other human perturbations associated with agricultural activities, and the density of them can be seen as an important gradient reflecting local disturbance. However, no studies to date have examined the changes in wetland communities in relation to drainage ditch densities, yet such information is urgently needed for the conservation of wetland ecosystems facing intensive cultivation. In this paper, we inventoried 67 plots at four wetland mosaics with the ditch density values ranged 0-3.6 km km[^-2] in the Sanjiang Plain, and the species richness, composition and diversity were compared among those four sites. Linear regression was used to explore relationships between wetland community pattern and agricultural ditch density, and the results show that there is significant relationship (r[^2] = 0.56, P <0.001). The diversity comparisons show that there exist a clear negative relationship between ditch density and species diversity indices, and the species diversity did not differ greatly among sites, but species composition varied considerably. With increasing ditch density, an increasing loss of indigenous wetland species paralleled with an increasing incursion of upland species. Management implication from the drainage ditches is that the density of 1.2 km km[^-2] be the maximum value suitable for the protection of native wetlands in Sanjiang plain.

4

The Effect of Mixed Support of Carbon Black and Nanographite on Catalytic Activity of Pt Catalysts for Methanol Electrooxidation

Teng Z., Wu B., Wang Y., Tang Y., Lu T., Gao Y.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 11

2197-2206

EN

The effect of mixed support of carbon black and nanographite (CG) on electrocatalytic activity and stability of the supported Pt catalyst for the methanol oxidation was investigated. It was found that the electrocatalytic activity and stability of the supported Pt catalyst for the methanol oxidation depended on the mass ratio of carbon black and nanographite. When the mass ratio was 10:1, the electrocatalytic activity and stability of the CG supported Pt (Pt/CG) catalyst for the methanol oxidation was the best.