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971.
An FM-CW radar system was applied to detect a human body buried in a very wet snowpack. This radar uses the L-band microwave frequency with a maximum output power of 100 mW, and utilizes digital signal processing techniques. Field experiments were carried out to detect and map a human body embedded at a depth of 125 cm in a natural snowpack. The radar is shown to have a potential ability to detect avalanche victims, indicating that it may become a tool for snow rescuer operations  相似文献   
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974.
A mode based on an additive mechanism of heat transfer is proposed for forced convection subcooled boiling of binary mixtures. The contributing modes of heat transfer are: (i) the heat transferred as latent heat by the rising bubbles, (ii) the heat transferred as the heat contained in the superheated thermal layer that is removed from the surface in the wake of the rising bubbles and (iii) the single phase forced convection heat transfer from the heating surface not influenced by the bubbles. Experimental data from the literature on binary systems show good agreement with the model, validating the postulated mechanism.  相似文献   
975.
Abstract: Non-classical fractals generated by many generators are of interest. Random fractals caused by the random action of given generators and by random generrrtors are discussed The generators may have different scales. The fractal spectral function, the generalized fractal dimensions and scaling index are derived explicitly. Examples include the cracking patterns of concrete mix.  相似文献   
976.
We recently found that cytochrome P450 aromatase (P450arom) is present in germ cells of the mammalian testis and is capable of converting androgens to estrogens in the male reproductive tract. The objective of the present study was to determine whether testicular germ cells and epididymal sperm of an avian species are also capable of synthesizing estrogen. P450arom was localized in the rooster testis and epididymal region by immunocytochemistry, using an antiserum generated against purified human placental cytochrome P450arom. Immunostaining was present in pachytene spermatocytes, round spermatids, elongated spermatids, flagella of late spermatids, and sperm in the epididymal region. A positive reaction was also found in nonciliated cells of the epididymal region. However, the absence of mRNA for P450arom in the epididymal region indicated that the immunoreactive protein present in the epididymal region is not synthesized in this region. The immunoreactive P450arom found in epididymal sperm was shown to be active through use of a 3H2O assay. On the basis of these data, we conclude that rooster testicular germ cells and epididymal sperm are sites for the synthesis of estrogen, a potential regulator or modulator of germinal epithelium in the testis and the epithelium of the epididymal region of the avian species.  相似文献   
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Watermarking for intellectual property protection   总被引:1,自引:0,他引:1  
Fan  Y.C. Tsao  H.W. 《Electronics letters》2003,39(18):1316-1318
A new watermarking method for intellectual property (IP) protection is presented. The proposed method uses a uniquely generated stream of bits, known as a watermark, embedded into the self-test circuit to represent ownership. This scheme can detect the ownership rights of the IP provider even when the chip has been packaged. Experimental results show the proposed embedding technique can survive synthesis, placement and routing. The experimental results are given to demonstrate the proposed method.  相似文献   
980.
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