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941.
942.
A method for the analysis of deformed patterns is presented and analyzed. The image is transformed into a new set of coordinates in which the deformation has a particular simple form. A number of deformations are considered. The practical implementation of the method is discussed. Similar aspects of biological vision are also considered  相似文献   
943.
Novel compounds RETSb2 have been prepared and characterized for T Cu (RE rare earth from La to Lu), Ni (RE La to Ho), Pd (RE La to Tb) and Au (RE La to Sm). From X-ray powder diffraction analyses all compounds were found to crystallize as the ZrCuSi2 type. Magnetic susceptibilities were generally measured in the temperature range from 4 to 100 K. YCuSb2 and LaTSbz are temperature-independent paramagnets. RETSb2 compounds are found to order antiferromagnetically below T = 20 K. PrPdSb2 and TbPdSb2 undergo metamagnetic transitions, whereas PrCuSb2 and ErCuSb2 are simple ferromagnets. The Sm-containing compounds are typical Van Vleck paramagnets owing to the closely spaced multiplets.  相似文献   
944.
This paper describes a simple and effective way to modify an existing hard-switched flyback power converter into a circuit with zero-voltage switching (ZVS) and zero-current switching (ZCS). The key improvement is to turn the unattractive features of the coupled inductor leakage inductance and snubber capacitor into attractive ones. The coupled inductor leakage inductance and snubber are used to form a quasi-resonant circuit to facilitate ZVS/ZCS of all power devices. The operating principles of the power converter and experimental results are presented  相似文献   
945.
Kapur et al. (1995) introduced the MinMax information measure, which is based on both maximum and minimum entropy. The major obstacle for using this measure, in practice, is the difficulty in finding the minimum entropy. An analytical expression has already been developed for calculating the minimum entropy when only variance is specified. An analytical formula is obtained for calculating the minimum entropy when only mean is specified, and numerical examples are given for illustration  相似文献   
946.
947.
Surgery of colorectal cancer is suited for assurance of surgical quality. The R0-resection rate in 1927 operations for colorectal cancer was 74.4%. The postoperative mortality was 7.1%. Wound suppuration occurred after surgery of the colon in 6.5%, after surgery of rectal cancer in 9.9% of the cases. In 68.6% of pT4-tumors we found lymphoid metastasis, in 19.3% around the trunk of the inferior mesenteric artery. For compilation of comparative data the quality assurance in colorectal surgery should be realised every 3 to 5 years.  相似文献   
948.
949.
950.
Milk and plasma N-acetyl-B-D-glucosaminidase activity was determined for cows during the dry and early postpartum periods. Milk samples were taken from individual quarters of 12 cows from 7 d preceding dry off until calving. Weigh jar milk samples were taken daily for 28 d postpartum from 9 of the 12 cows. Somatic cell concentration was also measured in the postpartum samples. N-Acetyl-B-D-glucosaminidase activity of mammary secretions was significantly elevated in the dry period. Activity in mammary secretions was significantly higher than blood plasma concentrations during the dry period, which suggests that the enzyme present in mammary secretions comes mainly from within the gland. Milk enzyme concentrations declined sharply by 4 d postpartum and gradually declined through 28 d postpartum. Activity was still slightly elevated at 28 d postpartum as compared with normal lactation. Greater daily variability was seen with somatic cells than with N-acetyl-B-D-glucosaminidase. However, somatic cells were more responsive to clinical infections postpartum, showing significant elevations in both clinical episodes. The enzyme was elevated in one clinical case, but relatively unchanged in the other. Plasma levels were constant throughout both trials.  相似文献   
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