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结合方案的积扩张与和扩张 被引量:2
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作者 张更生 宋占杰 《河北师范大学学报(自然科学版)》 CAS 1998年第1期4-6,共3页
给出了用已知结合方案构造出新结合方案的两种方法,即所谓的结合方案的积扩张与和扩张.
关键词 结合方案 积扩张 扩张 代数组合学
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CT诊断肠梗阻并发胆道扩张积气的临床分析
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作者 卓玛才旦 《中文科技期刊数据库(引文版)医药卫生》 2024年第12期135-138,共4页
分析CT诊断肠梗阻并发胆道扩张积气的临床价值。方法 选择我院2022年1月-2022年12月肠梗阻并发胆道扩张积气患者共60例,对其进行CT诊断和X线诊断,比较诊断的结果情况。结果 CT检查肠梗阻检出率更高,P<0.05。CT检查胆道扩张积气检出... 分析CT诊断肠梗阻并发胆道扩张积气的临床价值。方法 选择我院2022年1月-2022年12月肠梗阻并发胆道扩张积气患者共60例,对其进行CT诊断和X线诊断,比较诊断的结果情况。结果 CT检查肠梗阻检出率更高,P<0.05。CT检查胆道扩张积气检出率更高,P<0.05。CT检查图像更清晰,患者舒适度更高,P<0.05。结论 CT诊断肠梗阻并发胆道扩张积气的临床价值高,值得推广。 展开更多
关键词 CT诊断 肠梗阻 胆道扩张 临床价值
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基于扩张图卷积网络的SAR图像分类 被引量:2
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作者 叶乡凤 董张玉 杨学志 《智能计算机与应用》 2022年第7期69-73,79,共6页
合成孔径雷达(Synthetic Aperture Radar, SAR)图像存在相干斑噪声,且样本数量少,导致特征提取困难。为了提取更有表征力的特征,本文提出了一种基于扩张图卷积网络,用于SAR图像分类。该网络构造了一个新的残差扩张图卷积(Residual Dilat... 合成孔径雷达(Synthetic Aperture Radar, SAR)图像存在相干斑噪声,且样本数量少,导致特征提取困难。为了提取更有表征力的特征,本文提出了一种基于扩张图卷积网络,用于SAR图像分类。该网络构造了一个新的残差扩张图卷积(Residual Dilated Graph Convolutional, RDGC)模块。RDGC模块包含3个不同扩张率的图结构,通过卷积提取不同感受野的特征,并能够调整感受野的大小,以适应不同尺度的特征信息;在此基础上,叠加多个RDGC模块,通过将每个RDGC模块的输出进行特征融合,提取较多的细节信息;最后,将SAR图像经过粗提取后的特征附加在其上,形成全局的残差连接,在高层语义特征中融入低层空间特征,进一步补充细节信息,且避免了特征丢失和梯度消失。在两幅真实SAR图像上进行实验,结果表明:改进的图卷积网络模型优于现有网络的分类效果和性能。 展开更多
关键词 SAR图像分类 扩张图卷 特征融合 残差连接
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CT诊断肠梗阻并发胆道扩张积气1例
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作者 孙雷 《医学信息(医学与计算机应用)》 2014年第11期528-529,共2页
目的提高对肠梗阻并发胆道扩张积气诊断的认识。方法分析1例肠梗阻并发胆道扩张积气患者的临床病史及CT表现。结果 CT及临床诊断为肠梗阻并发胆道扩张积气。结论结合影像上及临床上与胆道积气同时存在的其它影像表现、临床病史等进行综... 目的提高对肠梗阻并发胆道扩张积气诊断的认识。方法分析1例肠梗阻并发胆道扩张积气患者的临床病史及CT表现。结果 CT及临床诊断为肠梗阻并发胆道扩张积气。结论结合影像上及临床上与胆道积气同时存在的其它影像表现、临床病史等进行综合分析,还要在影像诊断中注意考虑多个影像表现及临床症状之间的因果关系及主次关系,这样才能得到准确的诊断结果。 展开更多
关键词 肠梗阻 胆道扩张 CT
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超声在乳腺导管扩张积乳合并感染患者诊断中的应用研究
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作者 王晓燕 《基层医学论坛》 2015年第32期4531-4533,共3页
目的研究超声在乳腺导管扩张积乳合并感染患者诊断中的应用。方法回顾性分析2011年5月—2013年3月我院收治的62例乳腺肿块患者的临床资料。结果导管扩张积乳合并感染组、纤维腺瘤组、局灶性增生结节组患者乳腺疾病在外上、外下、内上、... 目的研究超声在乳腺导管扩张积乳合并感染患者诊断中的应用。方法回顾性分析2011年5月—2013年3月我院收治的62例乳腺肿块患者的临床资料。结果导管扩张积乳合并感染组、纤维腺瘤组、局灶性增生结节组患者乳腺疾病在外上、外下、内上、内下象限的分布比之间差异均不显著(P>0.05);导管扩张积乳合并感染组、纤维腺瘤组、局灶性增生结节组患者乳腺疾病在高回声壁、血流方面均具有显著差异(P<0.05),但在边界、形态、内部回声、后方回声、钙化方面的差异均不显著(P>0.05);导管扩张积乳合并感染组、纤维腺瘤组、局灶性增生结节组患者乳腺疾病的纵横比之间差异均不显著(P>0.05),但与乳头距离之间的差异均显著(P<0.05)。结论超声在乳腺导管扩张积乳合并感染患者诊断中的应用效果良好,能够显著提升诊断的准确性,同时有效鉴别其与纤维腺瘤、局灶性增生结节等良性病变。 展开更多
关键词 乳腺导管扩张乳合并感染 诊断 超声应用效果
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乳腺导管扩张积乳合并感染的病原学和药敏试验及超声图像特征分析 被引量:4
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作者 邢孔丽 薛文丹 +3 位作者 曾晶 陈豪权 李小清 王胜 《中华医院感染学杂志》 CAS CSCD 北大核心 2018年第6期900-903,共4页
目的分析乳腺导管扩张积乳合并感染患者的病原学、药敏试验及超声图像特征,为乳腺导管扩张积乳患者诊断和治疗方案的选择提供参考。方法回顾性分析医院2013年2月-2016年2月收治的96例乳腺导管扩张积乳合并感染患者的临床资料,所有患者... 目的分析乳腺导管扩张积乳合并感染患者的病原学、药敏试验及超声图像特征,为乳腺导管扩张积乳患者诊断和治疗方案的选择提供参考。方法回顾性分析医院2013年2月-2016年2月收治的96例乳腺导管扩张积乳合并感染患者的临床资料,所有患者均有明确的感染病原学及药敏试验结果,治疗前均行超声检查,整理患者病原菌分布情况及药敏试验结果及超声图像特征。结果 96例患者共检出病原菌124株,其中革兰阳性菌占59.67%,以表皮葡萄球菌、金黄色葡萄球菌为主,革兰阴性菌占40.33%,以嗜麦芽窄食单胞菌为主;药敏结果显示,革兰阳性菌对喹诺酮类(左氧氟沙星、莫西沙星)及四环素类(替加环素、四环素、万古霉素、利奈唑胺、呋喃妥因)耐药率较低,均<30%,对青霉素类和头孢菌素类抗菌药物的耐药率较高,均>30%,革兰阴性菌对氨基糖甙类、氟喹诺酮类抗菌药物敏感率较高,对氨苄西林、头孢唑林、头孢西丁耐药率较高;患者治疗前乳腺超声图像以出现肿块、肿块无明显包膜、边界呈毛玻璃状、肿块内部呈低回声且不均匀、周边高回声壁、部分病灶有冒泡征为主。结论乳腺导管扩张积乳合并感染患者感染病原菌主要为革兰阳性菌,其对喹诺酮类和四环素类抗菌药物较敏感,患者超声图像有较高的特异性,在对其鉴别诊断中具有一定价值。 展开更多
关键词 乳腺导管扩张 感染 病原学构成 药敏检查 超声图像特征
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Gorenstein dimensions for weak Hopf-Galois extensions
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作者 Wang Zhongwei 《Journal of Southeast University(English Edition)》 EI CAS 2020年第4期483-488,共6页
The representation of weak Hopf algebras is studied by investigating the Gorenstein dimensions of weak Hopf algebras and weak Hopf-Galois extensions.Let H be a weak Hopf algebra with a bijective antipode,A a weak righ... The representation of weak Hopf algebras is studied by investigating the Gorenstein dimensions of weak Hopf algebras and weak Hopf-Galois extensions.Let H be a weak Hopf algebra with a bijective antipode,A a weak right H-comodule algebra and B the H-coinvariant subalgebra of A.First,some properties of Gorenstein projective H-modules in the representation category are studied,and the fact that Gorenstein global dimension of H is the same as the Gorenstein projective dimension of its left unital subalgebra is demonstrated.Secondly,by applying the integral theory of weak Hopf algebras,on the one hand,a sufficient and necessary condition that a projective A-module is a projective B-module is given;on the other hand,the separability of the functor AB-and that of the restriction of scalar function B(-)are described,respectively.Finally,as a mean result,the Gorenstein global dimension of a weak Hopf-Galois extension is investigated under the condition that H is both semisimple and cosemisimple. 展开更多
关键词 weak Hopf algebra INTEGRAL weak Hopf-Galois extension Gorenstein dimension
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AN EXPANSION AND CORRECTION ALGORITHM FOR PHOTOELECTRIC IMAGE WITH GEOMETRIC DISTORTION^1
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作者 Liu Jingen Wu Zhipeng Liu Shangqian (Lab. 503, Xidian University, Xi’an 710071) 《Journal of Electronics(China)》 2003年第3期189-193,共5页
A creepy photoelectric endoscopy system with good performance is studied, and anexpansion and correction algorithm for a compressed photoelectric image with serious geometricdistortion is presented. The algorithm can ... A creepy photoelectric endoscopy system with good performance is studied, and anexpansion and correction algorithm for a compressed photoelectric image with serious geometricdistortion is presented. The algorithm can not only correct the geometric distortion, but alsorestore the gray-level distribution by means of ternary convolution algorithm. The details andthe outline in the image are very clear. It is proved to be of high performance in practice. 展开更多
关键词 Photoelectric image Geometric distortion Image expansion and correction Ternary convolution algorithm
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The Reduced Planck's Constant, Mach's Principle, Cosmic Acceleration and the Black Hole Universe
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作者 U.V. Satya Seshavatharam S. Lakshminarayana 《Journal of Physical Science and Application》 2012年第10期441-447,共7页
Based on the Mach's principle and the characteristic mass of the present universe, Mo a c3/2GHo, it is noticed that, 'rate of decrease in the laboratory fine structure ratio' is a measure of the cosmic rate of expa... Based on the Mach's principle and the characteristic mass of the present universe, Mo a c3/2GHo, it is noticed that, 'rate of decrease in the laboratory fine structure ratio' is a measure of the cosmic rate of expansion. If the observed laboratory fine structure ratio is a constant, then, independent of the cosmic red shift and CMBR observations, it can be suggested that, at present there is no cosmic acceleration. Obtained value of the present Hubble constant is 70.75 Km/sec/Mpc. If it is true that, rate of decrease in temperature is a measure of cosmic rate of expansion, then from the observed cosmic isotropy it can also be suggested that, at present there is no cosmic acceleration. At present if the characteristic mass of the universe is, Mo = c3/2GHo and if the primordial universe is a natural setting for the creation of black holes and other non-perturbative gravitational entities, it is also possible to assume that throughout its journey, the whole universe is a primordial growing and light speed rotating black hole. At any time, if cot is the angular velocity, then cosmic radius is c/ω1 and cosmic mass is c3/2Gω1 Instead of the Planck mass, initial conditions can be addressed with the Coulomb mass = Mc = √/4xeoG At present, if ω1= H0 the cosmic black hole's volume density, observed matter density and the thermal energy density are in geometric series and the geometric ratio is 1 + ln(M0 +Mc). 展开更多
关键词 Reduced Planck's constant cosmic mass CMB radiation cosmic acceleration primordial cosmic black hole.
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Global Plate Motions and Their Impact on the Earth's Surface Area Change 被引量:1
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作者 Cao Shuai Zhang Keliang Wei Dongping 《Earthquake Research in China》 2010年第3期344-352,共9页
Based on their Euler poles, we calculated the relative velocities between every two plates in the typical global plate motion models, respectively, and estimated the area change along these boundaries. In our calculat... Based on their Euler poles, we calculated the relative velocities between every two plates in the typical global plate motion models, respectively, and estimated the area change along these boundaries. In our calculations, plates on both sides accommodated area changes depending on the boundary types: extensional, convergent or transform, so we can estimate area change of each plate and then globally. Our preliminary results show that the area of the southern hemisphere increased while that of the northern hemisphere decreased over the past I million years, and global area has increased by 26,000km^2 to 36,000km^2, which corresponds to the 160m - 250m increment on the Earth's radius if all these area increments are attributed to Earth's expansion. Taking the NUVEL-1 model as an example, of the 14 plates in this model, 11 are decreasing, but the global area has increased because of the larger increment amount from Africa, North America and Antarctica. Finally, we also discussed factors affecting the global area change such as subduction zone retreating and back-arc spreading. 展开更多
关键词 Plate Motions NUVEL-1 Model Pacific Plate SUBDUCTION
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关于正规Fitting对
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作者 郭文彬 《Journal of Mathematical Research and Exposition》 CSCD 1992年第2期247-248,共2页
本文利用给出X—正规Fiting对的积,解决了两个X—正规Fitting类的交所对应的X—正规Fitting对与原两个X—正规Fitting类所对应的两个X—正规Fitting对之问的关系,同时给出了正规Fitting对的一个扩张定理以及Fitting对的积扩张的一个性质.
关键词 正规 Fitting对 扩张定理 积扩张
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Solvable base change and Rankin-Selberg convolutions
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作者 GILLESPIE Tim 《Science China Mathematics》 SCIE CSCD 2017年第1期99-112,共14页
Let π and π′ be unitary automorphic cuspidal representations of GL_n(A_E) and GL_m(A_F), and let E and F be solvable Galois extensions of Q of degrees ? and ?′, respectively. Using the fact that the automorphic in... Let π and π′ be unitary automorphic cuspidal representations of GL_n(A_E) and GL_m(A_F), and let E and F be solvable Galois extensions of Q of degrees ? and ?′, respectively. Using the fact that the automorphic induction and base change maps exist for E and F, and assuming an invariance condition under the actions of the Galois groups, we attach to the pair(π, π′) a Rankin-Selberg L-function L(s, π×E,Fπ′) for which we prove a prime number theorem. This gives a method for comparing two representations that could be defined over completely different extensions, and the main results give a measure of how many cuspidal components the two representations π and π′ have in common when automorphically induced down to the rational numbers. The proof uses the structure of the Galois group of the composite extension EF and the character groups attached to the fields via class field theory. The second main theorem also gives an indication of when the base change of π up to the composite extension EF remains cuspidal. 展开更多
关键词 automorphic L-function base change automorphic induction
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