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41.
SF Ding JD Delhanty JS Dooley L Bowles CB Wood NA Habib 《Canadian Metallurgical Quarterly》1993,17(3):405-409
We have previously shown that the tumor suppressor gene for hepatocellular carcinoma (HCC) without cirrhosis may be located on chromosome 5q35-qter. In this study, we analyzed nine cases of primary HCC without cirrhosis using probes from the MCC and APC genes, which are in the region 5q21-22. None of the informative cases had allele loss detected by these probes, whereas the probe lambda MS8 for the region 5q35-qter showed allele loss in six out of six informative cases. The results confirm that the putative tumor suppressor gene for HCC without cirrhosis on chromosome 5q is distinct from the MCC and APC genes. 相似文献
42.
43.
低相噪,低杂波数字锁相环路滤波器的设计 总被引:11,自引:0,他引:11
较详细地分析数字锁相频率合成器的相位噪声,着重用控制论方法对低相噪、低杂波锁相环的环路滤波器进行设计,并用某S波段频率合成器的实验结果进行了验证。 相似文献
44.
四川盆地中部上三叠统香溪群岩性油气藏圈闭类型及其特征 总被引:4,自引:0,他引:4
四川盆地川中地区构造平缓,大型断裂欠发育,已发现的油气藏与背斜关系并不十分密切。研究认为,川中地区香溪群主要发育岩性圈闭,根据圈闭形成主控因素,结合香溪群沉积前的古地貌特征和裂缝发育特点,将川中香溪群岩性圈闭划分为4种类型:①与地层尖灭相关的地层—岩性圈闭;②与沉积—成岩相变密切相关的成岩—岩性圈闭;③与古地貌有关的差异压实作用形成的岩性圈闭;④与断层转化调节相关的裂缝—岩性复合圈闭。其中成岩—岩性圈闭和地层—岩性圈闭,是川中香溪群最重要的、分布最广泛的圈闭类型。 相似文献
45.
文章讨论的基于“替换法”的汉字信息加、解密实现技术,改变了传统的汉字加密结果,使加密后的密文仍是可以识别和再利用的汉字,发送者可以在任何可编辑汉字的通讯设备上发送和接收密文,确保中文信息传输过程中的安全性。加、解密算法实现的代码语言为VFP6.0。 相似文献
46.
A novel route was developed to prepare PbS and HgS nanocrystals in ethanol solvent in the presence of sodium hydroxide by microwave heating method. PbS and HgS nanocrystals were obtained with an average size of approximately 10 and 6 nm, respectively. In the reaction, mercury acetate and lead acetate were used as mercury and lead source; sulfur powder was employed as chalcogenide source. The products were characterized by X-ray powder analysis (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV–Vis absorption spectroscopy. The probable mechanism was presented. 相似文献
47.
Analytical solution for the axisymmetric plane strain electroelastic dynamics of a special non-homogeneous piezoelectric hollow cylinder 总被引:1,自引:0,他引:1
By virtue of the introduction of a dependent variable and the separation of variables technique, the axisymmetric plane strain electroelastic dynamic problem of a special non-homogeneous piezoelectric hollow cylinder is transformed to a Volterra integral equation of the second kind about a function with respect to time, which can be solved successfully by means of the interpolation method. Then the solutions of displacements, stresses, electric displacements and electric potential are obtained. The present method is suitable for a piezoelectric hollow cylinder with an arbitrary thickness subjected to arbitrary mechanical and electrical loads. Numerical results are finally presented. 相似文献
48.
Soo-Chang Pei Jian-Jiun Ding 《Signal Processing, IEEE Transactions on》2004,52(7):2032-2046
The offset discrete Fourier transform (DFT) is a discrete transform with kernel exp[-j2/spl pi/(m-a)(n-b)/N]. It is more generalized and flexible than the original DFT and has very close relations with the discrete cosine transform (DCT) of type 4 (DCT-IV), DCT-VIII, discrete sine transform (DST)-IV, DST-VIII, and discrete Hartley transform (DHT)-IV. In this paper, we derive the eigenvectors/eigenvalues of the offset DFT, especially for the case where a+b is an integer. By convolution theorem, we can derive the close form eigenvector sets of the offset DFT when a+b is an integer. We also show the general form of the eigenvectors in this case. Then, we use the eigenvectors/eigenvalues of the offset DFT to derive the eigenvectors/eigenvalues of the DCT-IV, DCT-VIII, DST-IV, DST-VIII, and DHT-IV. After the eigenvectors/eigenvalues are derived, we can use the eigenvectors-decomposition method to derive the fractional operations of the offset DFT, DCT-IV, DCT-VIII, DST-IV, DST-VIII, and DHT-IV. These fractional operations are more flexible than the original ones and can be used for filter design, data compression, encryption, and watermarking, etc. 相似文献
49.
以基于欧玛技术的阅卷系统为例,介绍了用Excel实现大学英语分类成绩的接口及合并计算总评成绩的基本方法与步骤. 相似文献
50.
A nonlinear stress-strain relationship of soil reinforced with flexible geofibers under static loading is derived based on a nonlinear elastic stress-strain relationship of soil and a linear elastic stress-strain relationship of geofibers in the paper. This investigation includes the following aspects: First, the homogenization technique is introduced to find the volume average stress tensor and volume average strain tensor and further an elastic incremental stress-strain relation is introduced to describe deviatoric shear stress-axial strain relationship of equivalent homogeneous geofiber-reinforced soil. Second, the relation of geofiber numbers, content, mechanical behavior, distribution, and geometrical features to shear modulus of geofiber-reinforced soil is expressed and assessed by employing an elastic energy method. Third, the deviatoric shear stress and axial strain curves of geofiber-reinforced soil are calibrated by laboratory testing data of geofiber reinforced soil samples. Finally, the theoretical computational curves of geofiber reinforced soil are compared with the curves calibrated by testing data of geofiber reinforced soil. The model prediction has a good agreement with experimental results. 相似文献