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日本盆栽大师加藤三郎丛林式盆栽示范表演
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作者 赵庆泉 《花木盆景(下半月)》 2001年第6期26-26,共1页
在第一届世界盆栽大会上,日本盆栽协会理事长、盆栽大师加藤三郎先生和他的助手们共同作了一场丛林式盆栽示范表演,美国盆栽大师约翰·奈克担任了解说。表演所用的树木材料是20多株大小不一的虾夷松(其中含几株枯树),这是日本盆栽... 在第一届世界盆栽大会上,日本盆栽协会理事长、盆栽大师加藤三郎先生和他的助手们共同作了一场丛林式盆栽示范表演,美国盆栽大师约翰·奈克担任了解说。表演所用的树木材料是20多株大小不一的虾夷松(其中含几株枯树),这是日本盆栽的珍贵树种,引自北方四岛,树形高耸挺拔,针叶极短,很适合丛植。所用的盆为约150cm长的自然形态石板。 展开更多
关键词 日本盆栽 丛林式盆景 示范表
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Geometric Parameters of a Bocs (Ⅰ) 被引量:1
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作者 谢效训 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期103-109,共7页
In this paper, the group action of a local wild Bocs'rep. category is introduced. And, it computed the parametric numbers U(n) and P(n) of the rep. category mod n(A) and ind n(t) in case n=1,2 with geometric met... In this paper, the group action of a local wild Bocs'rep. category is introduced. And, it computed the parametric numbers U(n) and P(n) of the rep. category mod n(A) and ind n(t) in case n=1,2 with geometric method. 展开更多
关键词 local Bocs representation category group action parametric number
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Performance and Matching Cultivation Techniques of New Late Rice Variety Xiangyou196 with Early Maturity and High Yield
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作者 胡金和 徐宝庆 +5 位作者 王苏影 曾细华 刘宗发 祝飞 张志英 李苏明 《Agricultural Science & Technology》 CAS 2015年第4期659-661,674,共4页
In this paper, the characteristics and yield performance of new variety Xi-angyou196 were introduced, and its high-yielding cuItivation techniques were summa-rized, finally, the corresponding matching cuItivation tech... In this paper, the characteristics and yield performance of new variety Xi-angyou196 were introduced, and its high-yielding cuItivation techniques were summa-rized, finally, the corresponding matching cuItivation techniques through experiment and demonstration were put forward. 展开更多
关键词 New late rice varlety Demonstratlon performance Culti-vatlon techniques
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Quantum Groups by Ore Extensions Associated withGroup Algebras
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作者 李立斌 李尚志 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2002年第2期205-211,共7页
As a continuation of the work of Beattie on quantum groups constructed byOre extensions, in this paper, we characterize their centre and discuss the category ofquantum Yang-Baxter modules over them. In addition, we de... As a continuation of the work of Beattie on quantum groups constructed byOre extensions, in this paper, we characterize their centre and discuss the category ofquantum Yang-Baxter modules over them. In addition, we determine all finite dimen-sional irreducible representations over these quantum groups. 展开更多
关键词 Quantum group CENTRE quantum Yang-Baxter module irreducible repre-sentation.
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Progress and performance evaluation of Bei Dou global navigation satellite system: Data analysis based on BDS-3 demonstration system 被引量:75
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作者 Yuanxi YANG Yangyin XU +1 位作者 Jinlong LI Cheng YANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第5期614-624,共11页
The first two Medium Earth Orbit(MEO) satellites of the third generation of Bei Dou satellite navigation System(BDS-3) were successfully launched on November 5, 2017. This historical launch starts the new era of the g... The first two Medium Earth Orbit(MEO) satellites of the third generation of Bei Dou satellite navigation System(BDS-3) were successfully launched on November 5, 2017. This historical launch starts the new era of the global navigation satellite system of Bei Dou. Before the first two satellites of BDS-3, a demonstration system for BDS-3 with five satellites,including two Inclined Geosynchronous Orbit satellites(IGSO) and three MEO satellites, was established between 2015 and2016 for testing the new payloads, new designed signals and new techniques. In the demonstration system, the new S frequency signal and satellite hydrogen clock as well as inter-satellite link(ISL) based on Ka-band signals with time-division multiple addresses(TDMA) were tested. This paper mainly analyzes the performances of the demonstration system, including the signalto-noise ratios, pseudorange errors and the multipath errors of the civilian signals of BDS-3. The qualities of signals in space,time synchronization and timing precision were tested as well. Most of the performances were compared with those of the regional Bei Dou satellite navigation system(BDS-2). At last, the performances of positioning, navigation and timing(PNT) of the future Bei Dou global system(BDS-3) were evaluated based on the signal quality of the present demonstration satellite system. 展开更多
关键词 Bei Dou-3 Demonstration satellite Signal Timing Signal-to-noise ratios
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Range Profile Target Recognition Using Sparse Representation Based on Feature Space
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作者 吕文涛 王军锋 +1 位作者 郁文贤 包晓敏 《Journal of Shanghai Jiaotong university(Science)》 EI 2017年第5期615-623,共9页
A novel method is presented to improve the recognition rate of warhead in this paper. Firstly, a tool for electromagnetic calculation, like CST Microwave Studio, is used to simulate the frequency response of the elect... A novel method is presented to improve the recognition rate of warhead in this paper. Firstly, a tool for electromagnetic calculation, like CST Microwave Studio, is used to simulate the frequency response of the electromagnetic scattering. Secondly, the echo and further the range profile are acquired from the frequency response by further processing. Thirdly, a set of discriminative features is extracted from the range profiles of the target. Fourthly, these features are used to construct a dictionary for the sparse representation classifier. Finally, the sample of the target can be classified by solving the sparsest coefficients. Since the reconstruction result is determined by a linear combination of the training samples, this method has a good robustness for the variable features. By formulating the problem within a feature-based sparse representation framework, the presented method combines the discriminative features of each sample during the sparse recovery process rather than in a postprocessing manner. Moreover, based on the feature representation space rather than a single feature or image pixel, the constructed dictionary exhibits both strong expressive and discriminative powers that can enhance the classification performance of the test sample. A series of test results based on the simulated data demonstrates the effectiveness of our method. © 2017, Shanghai Jiaotong University and Springer-Verlag GmbH Germany. 展开更多
关键词 TECHNOLOGY
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