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This paper shows a method to calibrating the non-uniformity of the x-ray backscatter image in a side-beam x-ray detection system. The flying spot of x-ray beam cross the luggage under detection per cycle, and every point of the detector being irradiated by flying spot can be taken as an assumed detector. Using calibrators of different thickness and combined with the corresponding mathematical model, the greyscale of the image is uniformed and calibration is achieved.

The scale-location specific control on vegetation distribution was investigated through continuous wavelet transforms approaches in subtropical mountain-hill region, Fujian, China. The Normalized Difference Vegetation Index (NDVI) was calculated as an indicator of vegetation greenness using Chinese Environmental Disaster Reduction Satellite images along latitudinal and longitudinal transects. Four scales of variations were identified from the local wavelet spectrum of NDVI, with much stronger wavelet variances observed at larger scales. The characteristic scale of vegetation distribution within mountainous and hilly regions in Southeast China was around 20 km. Significantly strong wavelet coherency was generally examined in regions with very diverse topography, typically characterized as small mountains and hills fractured by rivers and residents. The continuous wavelet based approaches provided valuable insight on the hierarchical structure and its corresponding characteristic scales of ecosystems, which might be applied in defining proper levels in multilevel models and optimal bandwidths in Geographically Weighted Regression.

Yunnan Province of China is one of the important centers for origin and evolution of cultivated rice worldwide. Wild rice is the ancestor of the cultivated rice. Many elite traits of wild rice have widened the genetic basis in cultivated rice. However, many populations of wild rice species have disappeared in the past few years. Therefore, the current status of wild rice resources should be updated and the genetic diversity of wild rice species should be examined for further germplasm preservation and utilization. Our investigations showed that the number of natural wild rice populations declined sharply in Yunnan Province during the past few years due to various reasons. Fortunately, one population of Oryza rufipogon, three of O. officinalis and ten of O. granulata have been newly found in different ecological sites, which were confirmed by inter-simple sequence repeat (ISSR) marker analysis in this study. ISSR analysis and investigation of some important traits of nutritional values indicated that the genetic diversity of the currently existing wild rice resources in Yunnan is still rich. The demonstration of genetic diversity of wild rice by a combined use of geographical distribution, morphological traits, nutrition contents and ISSR markers would be helpful for the conservation and exploration of these important wild rice resources.

Biomedical Engineering of Electronic Engineering Deparment, Fudan University Shanghai, 200433 Based on the pulse-coded transmitting and wide-band receiving system, this paper describes a research of phase design a special power management circuit according to the particular demands of a real-time and continuously monitor system is essential. Combined with the requirement of voltage and current in separated module, three aspect must be considered, that is, how to select the functional component, how to accomplish voltage converting and how to carry on battery management. The test at last shows that, using this circuit and the 4400 mAh battery the energy utilization is more than 88%, and the work time is more than 20 hours.

In order to supply the multichannel electrical stimulator, a DC-DC flyback switch mode power supply based on a high-performance current mode controller UC3845 has been designed. The experimental results indicate that the power supply has satisfied the demands and can supply the multichannel electrical stimulator and similar apparatuses.