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视皮层V1区简单细胞的稀疏编码策略 被引量:9
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作者 杨谦 齐翔林 汪云九 《计算物理》 CSCD 北大核心 2001年第2期143-146,共4页
哺乳动物纹状皮层简单细胞的空间感受野在电生理实验中被描述为局部、具有朝向和带通性质的信号编码检测器 ,它针对图象产生电发放的输出活动呈现稀疏分布的形式 .从检测图象的物理过程入手建立了一个基于超定完备基的简单细胞集群稀疏... 哺乳动物纹状皮层简单细胞的空间感受野在电生理实验中被描述为局部、具有朝向和带通性质的信号编码检测器 ,它针对图象产生电发放的输出活动呈现稀疏分布的形式 .从检测图象的物理过程入手建立了一个基于超定完备基的简单细胞集群稀疏编码的计算模型 。 展开更多
关键词 感受野 自组织学习 稀疏编码 超定基 视觉皮层V1区 电生理实验
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Supramolecular Fixation of Three Amines using Cobalt Tetraphenyl- porphyrin for SO2 Removal
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作者 蓝公家 张建斌 +2 位作者 赵天翔 许秋霞 魏雄辉 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第5期616-620,I0004,共6页
In this work, supramolecular fixation of three amines, including aniline, ethylenediamine, and diethylamine, using cobalt tetraphenylporphyrin (CoTPP) for SO2 removal was studied using UV-Vis and fluorescence measur... In this work, supramolecular fixation of three amines, including aniline, ethylenediamine, and diethylamine, using cobalt tetraphenylporphyrin (CoTPP) for SO2 removal was studied using UV-Vis and fluorescence measurements. The UV-Vis spectra showed that increasing amines concentrations resulted in bathochromic shift for CoTPP Soret absorption band (B band). Once SO2 was introduced, it competed with CoTPP for aniline, ethylenediamine, and diethylamine, which eventually led to the release of CoTPP and the change of solution colour/absorption band. After that, the CoTPP was regenerated and got back to the first state. The fluorescence spectra offered that CoTPP interacted with aniline, ethylenediamine, and diethylamine to form 1:1 molecular adducts. The interactions of CoTPP with aniline, ethylenediamine, and diethylamine were entropy-driven. The interaction of CoTPP with aniline and diethylamine was endothermic, and that with ethylenediamine was exothermic. Ethylenediamine presented a stronger binding constant value for CoTPP, so it was considered as a potential agent for SO2 removal. 展开更多
关键词 Amine SO2 Supramolecular fixation Cobalt tetraphenylporphyrin
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The Fundamental Theorem of Ultraproducts in Lattice valued Model for L_α Logic
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作者 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第2期5-9, ,共5页
In this paper we add some new corcollary and theorems to [1],in particular,we show the fundamental theorem of ultraproducts in lattice valued model for L α logic. As a corollary,we get the α compactness theorem for... In this paper we add some new corcollary and theorems to [1],in particular,we show the fundamental theorem of ultraproducts in lattice valued model for L α logic. As a corollary,we get the α compactness theorem for L_α logic. 展开更多
关键词 ULTRAPRODUCT lattice valued model L_α language
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Global localization of in-pipe robot based on ultra-long wave antenna array and global position system 被引量:4
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作者 齐海铭 Zhang Xiaohua +2 位作者 Chen Hongjun Sun Dongchang Sun Yongtai 《High Technology Letters》 EI CAS 2009年第2期120-125,共6页
A global localization system of in-pipe robot is introduced in this paper.Global position system(GPS)is applied to monitor the motion of robot along the whole pipeline which is equally divided intomany segments by tra... A global localization system of in-pipe robot is introduced in this paper.Global position system(GPS)is applied to monitor the motion of robot along the whole pipeline which is equally divided intomany segments by tracking stations.The definite segment in which robot existing can be detected and thisis long-range localization.Ultra-long wave(ULW)is adopted to solve the problem of metallic shieldingand realize effective communication between inside and outside of pipeline.ULW emitter is carried byrobot.When the plant is broken or defects on pipe-wall are inspected,the robot will stop moving.Anten-na array is presented and disposed upon the definite segment to search the accurate location of robot,andthis is short-range localization.In this paper,five-antenna array is adopted and an effective linear signalfusion algorithm is presented.The localization precision reaches R < 25cm.By tests in Shengli oil field,the whole system is verified with robust solutions. 展开更多
关键词 pipeline robot uhra-long wave (ULW) global localization antenna array signal fusion
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Analysis of tunnel face stability with advanced pipes support 被引量:15
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作者 AN Yong-lin ZHOU Jin +1 位作者 OUYANG Peng-bo LI Jia-hao 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第2期604-617,共14页
To keep the tunnel face stable is very important for tunnel construction.In this paper,the tunnel face stability under the advanced pipe was analyzed using the Winkler foundation model and rigid limit equilibrium.The ... To keep the tunnel face stable is very important for tunnel construction.In this paper,the tunnel face stability under the advanced pipe was analyzed using the Winkler foundation model and rigid limit equilibrium.The tunnel face deformation characteristics were also analyzed using the numerical simulation.The influence of parameters on the deflection of the pipe roof and the stability of the tunnel face were discussed.The results show that the tunnel face stability can be improved through increasing the pipe diameter,decreasing the initial displacement at the beginning of the pipe seat,and adopting the short round length and small excavation height.With the increase of tunnel burial depth,the safety factor of tunnel face stability first decreases,then increases,and then remains unchanged.The deformation at the center of the tunnel face is larger than the deformation at the surround sides and at the corner.The horizontal displacement varies little with the increasing of the pipe length.The horizontal displacement at the center of the tunnel face increases with the increase of the pipe ring spacing and the pipe longitudinal spacing.There is an optimum external angle. 展开更多
关键词 tunnel face stability advanced pipe Winkler foundation model numerical simulation
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Identifying the genes of unconventional high temperature superconductors 被引量:5
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作者 Jiangping Hu 《Science Bulletin》 SCIE EI CAS CSCD 2016年第7期561-569,共9页
We elucidate a recently emergent framework in unifying the two families of high temperature (high To) superconductors, cuprates and iron-based superconductors. The unification suggests that the latter is simply the ... We elucidate a recently emergent framework in unifying the two families of high temperature (high To) superconductors, cuprates and iron-based superconductors. The unification suggests that the latter is simply the counterpart of the former to realize robust extended s-wave pairing symmetries in a square lattice. The unification identifies that the key ingredients (gene) of high Tc superconductors is a quasi two dimensional electronic environment in which the d-orbitals of cations that partic- ipate in strong in-plane couplings to the p-orbitals of anions are isolated near Fermi energy. With this gene, the superexchange magnetic interactions mediated by anions could maximize their contributions to superconductivity. Creating the gene requires special arrangements between local electronic structures and crystal lattice structures. The speciality explains why high Tc superconductors are so rare. An explicit prediction is made to realize high Tc superconductivity in Co/Ni-based materials with a quasi two dimensional hexagonal lattice structure formed by trigonal bipyramidal complexes. 展开更多
关键词 CUPRATES Iron-based superconductors Unconventional high Tc superconducotors SUPEREXCHANGE
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Porous aromatic framework(PAF-1) as hyperstable platform for enantioselective organocatalysis
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作者 Peng Chen Jin-Shi Sun +3 位作者 Lei Zhang Wen-Yue Ma Fuxing Sun Guangshan Zhu 《Science China Materials》 SCIE EI CSCD 2019年第2期194-202,共9页
High density of phenyl rings makes PAF-1 have robust structure and highly lipophilic pore, which make it very suitable for organocatalysis. However, there is no report about using PAF-1 as platform for enantioselectiv... High density of phenyl rings makes PAF-1 have robust structure and highly lipophilic pore, which make it very suitable for organocatalysis. However, there is no report about using PAF-1 as platform for enantioselective organocatalysis.In this paper, using PAF-1 as the platform, a chiral prolinamide catalytic site was introduced onto the framework of PAF-1 via a series of stepwise post-synthetic modifications,obtaining a novel PAF-supported chiral catalyst named PAF-1-NHPro. Then its enantioselective catalytic performance was studied by subjecting it to catalyze the model Aldol reaction between p-nitrobenzaldehyde and cyclohexanone.PAF-1-NHPro showed good diastereoselectivity and enantioselectivity with excellent and easy recyclability. 展开更多
关键词 porous aromatic frameworks L-prolinamide heterogeneous enantioselective organocatalysis Aldol reaction
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