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PMA2004数码相机大赏——单反数码相机争锋
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作者 张熙平 月亮斯坦 《数码》 2004年第3期32-33,共2页
一年一届的美国最盛大的摄像器材展示会(简称PMA)于2004年2月12日~15日在拉斯维加斯开幕,在这次展会上,数码相机可谓出尽了风头,各大厂商纷纷展示了从低端的民用消费机种,到高端的单反结构数码相机各个产品线新品,其中不乏首次... 一年一届的美国最盛大的摄像器材展示会(简称PMA)于2004年2月12日~15日在拉斯维加斯开幕,在这次展会上,数码相机可谓出尽了风头,各大厂商纷纷展示了从低端的民用消费机种,到高端的单反结构数码相机各个产品线新品,其中不乏首次面世的新品以及一些摄影爱好者期待已久的产品,《数码》杂志在此将给出最为详细的产品报道。如果你是数码相机的爱好者,相信不会错过这次大型的产品展示机会;如果你正准备出手购买相机,在此我们也建议你稍等一下,看看今年的新品有何出彩之处,相信大家可以从今年的新品中造出一款最适合自己的相机! 展开更多
关键词 单反数码相机 PMA2004 单反结构 选购
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DiMAGE 7Hi
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《个人电脑》 2003年第6期81-82,共2页
关键词 美能达公司 DIMAGE 7Hi 数字相机 等效焦距 GT镜头 JPEG压缩格式 单反结构
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Improved Particle Swarm Optimization for Solving Transient Nonlinear Inverse Heat Conduction Problem in Complex Structure 被引量:1
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作者 ZHOU Ling ZHANG Chunyun +2 位作者 BAI Yushuai LIU Kun CUI Miao 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第5期816-828,共13页
Accurately solving transient nonlinear inverse heat conduction problems in complex structures is of great importance to provide key parameters for modeling coupled heat transfer process and the structure’s optimizati... Accurately solving transient nonlinear inverse heat conduction problems in complex structures is of great importance to provide key parameters for modeling coupled heat transfer process and the structure’s optimization design.The finite element method in ABAQUS is employed to solve the direct transient nonlinear heat conduction problem.Improved particle swarm optimization(PSO)method is developed and used to solve the transient nonlinear inverse problem.To investigate the inverse performances,some numerical tests are provided.Boundary conditions at inaccessible surfaces of a scramjet combustor with the regenerative cooling system are inversely identified.The results show that the new methodology can accurately and efficiently determine the boundary conditions in the scramjet combustor with the regenerative cooling system.By solving the transient nonlinear inverse problem,the improved particle swarm optimization for solving the transient nonlinear inverse heat conduction problem in a complex structure is verified. 展开更多
关键词 improved particle swarm optimization transient nonlinear heat conduction problem inverse identification finite element method complex structure
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Enantioselective synthesis of mixed 3,3’-bisindoles via a phosphine-catalyzed umpolung γ-addition of 3’-indolyl-3-oxindoles to allenoates 被引量:1
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作者 Yildiz Tasdan Guang-Jian Mei Yixin Lu 《Science Bulletin》 SCIE EI CAS CSCD 2020年第7期557-563,M0004,共8页
An enantioselective umpolung γ-addition reaction of 3’-indolyl-3-oxindoles to allenoates catalyzed by amino acid-derived bifunctional phosphine catalysts has been developed. A wide range of chiral mixed 3,3’-bisind... An enantioselective umpolung γ-addition reaction of 3’-indolyl-3-oxindoles to allenoates catalyzed by amino acid-derived bifunctional phosphine catalysts has been developed. A wide range of chiral mixed 3,3’-bisindole scaffolds containing an all-carbon quaternary stereogenic center were obtained in high yields and with excellent enantioselectivities. 3,3’-Bisindoles are valuable synthetic intermediates, the employment of which led to formal total syntheses of(+)-Chimonanthine,(+)-Folicanthine and(-)-Calycanthine, as well as facile creation of useful pyrrolidinoindoline core structure. 展开更多
关键词 Umpolung c-addition Amino acid-derived bifunctional phosphine ALLENOATES Mixed 3 30-Bisindole Formal total syntheses
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