We consider the problem of packing d-dimensional cubes into the minimum number of 2-space bounded unit cubes. Given a sequence of items, each of which is a d-dimensional （d ≥ 3） hypercube with side length not great...We consider the problem of packing d-dimensional cubes into the minimum number of 2-space bounded unit cubes. Given a sequence of items, each of which is a d-dimensional （d ≥ 3） hypercube with side length not greater than 1 and an infinite number of d-dimensional （d ≥ 3） hypercube bins with unit length on each side, we want to pack all of the items in the sequence into the minimum number of bins. The constraint is that only two bins are active at anytime during the packing process. Each item should be orthogonally packed without overlapping other items. Items are given in an online manner without the knowledge of or information about the subsequent items. We extend the technique of brick partitioning for square packing and obtain two results： a three-dimensional box and d-dimensional hyperbox partitioning schemes for cube and hypercube packing, respectively. We design 32 5.43-competitive and 32/21·2d-competitive algorithms for cube and hypercube packing, respectively. To the best of our knowledge these are the first known results on 2-space bounded cube and hypercube packing.展开更多
Minimax state estimation is discussed for uncerttain systems with L2 bounded constraint. A dtaity relation-equality is introduced to estimate terminal state variabes x(T) by measurable outputs . hawing a game theory, ...Minimax state estimation is discussed for uncerttain systems with L2 bounded constraint. A dtaity relation-equality is introduced to estimate terminal state variabes x(T) by measurable outputs . hawing a game theory, opti-mal estimation leads to a simple solution. LQL control scheme, is further discussed to make it rational in the actual application.展开更多
This paper is concerned with the minimizers of L^(2)-subcritical constraint variar tional problems with spatially decaying nonlinearities in a bounded domain Ω of R~N(N≥1).We prove that the problem admits minimizers...This paper is concerned with the minimizers of L^(2)-subcritical constraint variar tional problems with spatially decaying nonlinearities in a bounded domain Ω of R~N(N≥1).We prove that the problem admits minimizers for any M> 0.Moreover,the limiting behavior of minimizers as M→∞ is also analyzed rigorously.展开更多
目的探讨磁共振三维可变翻转角快速自旋回波成像技术(SPACE)在显示肺球形病灶内部血管的临床应用价值。方法搜集拟进行胸部CT增强扫描的患者30例,所有患者均在接受CT增强检查后24 h内进行MR检查。扫描序列包括T1WI 3D Star VIBE序列、T2...目的探讨磁共振三维可变翻转角快速自旋回波成像技术(SPACE)在显示肺球形病灶内部血管的临床应用价值。方法搜集拟进行胸部CT增强扫描的患者30例,所有患者均在接受CT增强检查后24 h内进行MR检查。扫描序列包括T1WI 3D Star VIBE序列、T2WI HASTE序列以及T2-SPACE FLOW序列。由2名具有10年以上工作经验的放射科医师采用盲法先对MRI图像上所有病灶中肺血管的显示度进行主观评价,再观察与之对应的CT增强图像上肺血管的显示能力(CT增强图像作为参考标准),评分标准采用4分法(4分:边缘非常清晰,3分:边缘较清晰,2分:边缘不清晰,1分:不可见)。结果 CT增强图像上共检出48个肺球形病灶(大小1.0~5.6 cm),69支肺血管,另于MRI T2-SPACE FLOW序列上,检出48个球形病灶64支肺血管,检出率为94.3%。两名医师对CT增强图像和MRI图像上对肺球形病变内部血管形态显示度的主观评分分别为(3.59±0.46)分和(3.42±0.39)分(医师1)、(3.61±0.22)分和(3.49±0.68)分(医师2),差异均无统计学意义(P>0.05)。结论在显示肺球形病变内部血管中,T2-SPACE FLOW序列具有较高的敏感度及准确率,同时可以提供和CT增强扫描同等效能的肺血管显示度,具有重要的临床价值。展开更多
Genome-wide epigenomic datasets allow us to validate the biological function of motifs and understand the regulatory mechanisms more comprehensively. How different motifs determine whether transcription factors (TFs) ...Genome-wide epigenomic datasets allow us to validate the biological function of motifs and understand the regulatory mechanisms more comprehensively. How different motifs determine whether transcription factors (TFs) can bind to DNA at a specific position is a critical research question. In this project, we apply computational techniques that were used in Natural Language Processing (NLP) to predict the Transcription Factor Bound Regions (TFBRs) given motif instances. Most existing motif prediction methods using deep neural network apply base sequences with one-hot encoding as an input feature to realize TFBRs identification, contributing to low-resolution and indirect binding mechanisms. However, how the collective effect of motifs on binding sites is complicated to figure out. In our pipeline, we apply Word2Vec algorithm, with names of motifs as an input to predict TFBRs utilizing Convolutional Neural Network (CNN) to realize binary classification, based on the ENCODE dataset. In this regard, we consider different types of motifs as separate “words”, and their corresponding TFBR as the meanings of “sentences”. One “sentence” itself is merely the combination of these motifs, and all “sentences” compose of the whole “passage”. For each binding site, we do the binary classification within different cell types to show the performance of our model in different binding sites and cell types. Each “word” has a corresponding vector in high dimensions, and the distances between each vector can be figured out, so we can extract the similarity between each motif, and the explicit binding mechanism from our model. We apply Convolutional Neural Network (CNN) to extract features in the process of mapping and pooling from motif vectors extracted by Word2Vec Algorithm and gain the result of 87% accuracy at the peak.展开更多
A single-Rh-site catalyst(Rh-TPISP)that was ionically-embedded on a P(V)quaternary phosphonium porous polymer was evaluated for heterogeneous ethanol carbonylation.The[Rh(CO)I_(3)]^(2-)unit was proposed to be the acti...A single-Rh-site catalyst(Rh-TPISP)that was ionically-embedded on a P(V)quaternary phosphonium porous polymer was evaluated for heterogeneous ethanol carbonylation.The[Rh(CO)I_(3)]^(2-)unit was proposed to be the active center of Rh-TPISP for the carbonylation reaction based on detailed Rh L3-edge X-ray absorption near edge structure(XANES),X-ray photoelectron spectroscopy(XPS),and Rh extended X-ray absorption fine structure(EXAFS)analyses.As the highlight of this study,Rh-TPISP displayed distinctly higher activity for heterogeneous ethanol carbonylation than the reported catalytic systems in which[Rh(CO)_(2)I_(2)]^(-)is the traditional active center.A TOF of 350 h^(-1)was obtained for the reaction over[Rh(CO)I_(3)]^(2-),with>95%propionyl selectivity at 3.5 MPa and 468 K.No deactivation was detected during a near 1000 h running test.The more electron-rich Rh center was thought to be crucial for explaining the superior activity and selectivity of Rh-TPISP,and the formation of two ionic bonds between[Rh(CO)I_(3)]^(2-)and the cationic P(V)framework([P]^(+))of the polymer was suggested to play a key role in firmly immobilizing the active species to prevent Rh leaching.展开更多
We present a new six-dimensional potential energy surface for He-H2S including the intramolecular Q1,Q2,and Q3 normal modes for theν1 symmetric stretching,ν2 bending andν3 asymmetric stretching of H2S.The potential...We present a new six-dimensional potential energy surface for He-H2S including the intramolecular Q1,Q2,and Q3 normal modes for theν1 symmetric stretching,ν2 bending andν3 asymmetric stretching of H2S.The potential was calculated at the coupled-cluster singles and doubles with noniterative inclusion of connected triples[CCSD(T)]-F12a level with augmented correlation-consistent polarized-valence triple-zeta(aug-cc-p VTZ)basis set plus the midpoint bond function(3s3p2d1f1g).Three vibrationally averaged potentials with H2S at the vibrational ground stateν1 as well as the excited statesν2 andν3 were generated from the integration of the six-dimensional potential over the Q1,Q2 and Q3 coordinates.Each potential has a planar T-shaped global minimum,a planar local minimum,two inplane saddle points as well as an out-plane saddle point.The global minimum is located at R=3.46A,θ=109.9° andφ=0.0° with a well depth of 35.301 cm^-1.The radial discrete variable representation/angular finite basis representation method and the Lanczos algorithm were employed to calculate the rovibrational energy levels.The calculated band origins are blue-shifted(0.025 cm^-1 and 0.031 cm^-1)and(0.041 cm^-1 and 0.060 cm^-1)for He-(paraH2S)and He-(ortho-H2S)in theν2 andν3 region of the H2S molecule,respectively.展开更多
In this paper,we introduce a special class of nilpotent Lie groups defined by hermitian maps,which includes all the groups of affine holomorphic automorphisims of Siegel domains of type Ⅱ,in particular,the Heisenberg...In this paper,we introduce a special class of nilpotent Lie groups defined by hermitian maps,which includes all the groups of affine holomorphic automorphisims of Siegel domains of type Ⅱ,in particular,the Heisenberg group.And we study harmonic analysis on these groups as spectral theory of the associated Sub-Laplacian instead of the group representation theory in usual way.展开更多
基金supported by the National Natural Science Foundation of China (No. 61170232)the 985 Project funding of Sun Yat-sen UniversityState Key Laboratory of Rail Traffic Control and Safety independent research (No. RS2012K011)
文摘We consider the problem of packing d-dimensional cubes into the minimum number of 2-space bounded unit cubes. Given a sequence of items, each of which is a d-dimensional （d ≥ 3） hypercube with side length not greater than 1 and an infinite number of d-dimensional （d ≥ 3） hypercube bins with unit length on each side, we want to pack all of the items in the sequence into the minimum number of bins. The constraint is that only two bins are active at anytime during the packing process. Each item should be orthogonally packed without overlapping other items. Items are given in an online manner without the knowledge of or information about the subsequent items. We extend the technique of brick partitioning for square packing and obtain two results： a three-dimensional box and d-dimensional hyperbox partitioning schemes for cube and hypercube packing, respectively. We design 32 5.43-competitive and 32/21·2d-competitive algorithms for cube and hypercube packing, respectively. To the best of our knowledge these are the first known results on 2-space bounded cube and hypercube packing.
文摘Minimax state estimation is discussed for uncerttain systems with L2 bounded constraint. A dtaity relation-equality is introduced to estimate terminal state variabes x(T) by measurable outputs . hawing a game theory, opti-mal estimation leads to a simple solution. LQL control scheme, is further discussed to make it rational in the actual application.
基金supported by the Graduate Education Innovation Funds(2022CXZZ088)at Central China Normal University in Chinasupported by the NSFC(12225106,11931012)the Fundamental Research Funds(CCNU22LJ002)for the Central Universities in China。
文摘This paper is concerned with the minimizers of L^(2)-subcritical constraint variar tional problems with spatially decaying nonlinearities in a bounded domain Ω of R~N(N≥1).We prove that the problem admits minimizers for any M> 0.Moreover,the limiting behavior of minimizers as M→∞ is also analyzed rigorously.
文摘Genome-wide epigenomic datasets allow us to validate the biological function of motifs and understand the regulatory mechanisms more comprehensively. How different motifs determine whether transcription factors (TFs) can bind to DNA at a specific position is a critical research question. In this project, we apply computational techniques that were used in Natural Language Processing (NLP) to predict the Transcription Factor Bound Regions (TFBRs) given motif instances. Most existing motif prediction methods using deep neural network apply base sequences with one-hot encoding as an input feature to realize TFBRs identification, contributing to low-resolution and indirect binding mechanisms. However, how the collective effect of motifs on binding sites is complicated to figure out. In our pipeline, we apply Word2Vec algorithm, with names of motifs as an input to predict TFBRs utilizing Convolutional Neural Network (CNN) to realize binary classification, based on the ENCODE dataset. In this regard, we consider different types of motifs as separate “words”, and their corresponding TFBR as the meanings of “sentences”. One “sentence” itself is merely the combination of these motifs, and all “sentences” compose of the whole “passage”. For each binding site, we do the binary classification within different cell types to show the performance of our model in different binding sites and cell types. Each “word” has a corresponding vector in high dimensions, and the distances between each vector can be figured out, so we can extract the similarity between each motif, and the explicit binding mechanism from our model. We apply Convolutional Neural Network (CNN) to extract features in the process of mapping and pooling from motif vectors extracted by Word2Vec Algorithm and gain the result of 87% accuracy at the peak.
文摘A single-Rh-site catalyst(Rh-TPISP)that was ionically-embedded on a P(V)quaternary phosphonium porous polymer was evaluated for heterogeneous ethanol carbonylation.The[Rh(CO)I_(3)]^(2-)unit was proposed to be the active center of Rh-TPISP for the carbonylation reaction based on detailed Rh L3-edge X-ray absorption near edge structure(XANES),X-ray photoelectron spectroscopy(XPS),and Rh extended X-ray absorption fine structure(EXAFS)analyses.As the highlight of this study,Rh-TPISP displayed distinctly higher activity for heterogeneous ethanol carbonylation than the reported catalytic systems in which[Rh(CO)_(2)I_(2)]^(-)is the traditional active center.A TOF of 350 h^(-1)was obtained for the reaction over[Rh(CO)I_(3)]^(2-),with>95%propionyl selectivity at 3.5 MPa and 468 K.No deactivation was detected during a near 1000 h running test.The more electron-rich Rh center was thought to be crucial for explaining the superior activity and selectivity of Rh-TPISP,and the formation of two ionic bonds between[Rh(CO)I_(3)]^(2-)and the cationic P(V)framework([P]^(+))of the polymer was suggested to play a key role in firmly immobilizing the active species to prevent Rh leaching.
基金supported by the National Natural Science Foundation of China(No.21973065)Sichuan Science and Technology Program(No.2018JY0172)。
文摘We present a new six-dimensional potential energy surface for He-H2S including the intramolecular Q1,Q2,and Q3 normal modes for theν1 symmetric stretching,ν2 bending andν3 asymmetric stretching of H2S.The potential was calculated at the coupled-cluster singles and doubles with noniterative inclusion of connected triples[CCSD(T)]-F12a level with augmented correlation-consistent polarized-valence triple-zeta(aug-cc-p VTZ)basis set plus the midpoint bond function(3s3p2d1f1g).Three vibrationally averaged potentials with H2S at the vibrational ground stateν1 as well as the excited statesν2 andν3 were generated from the integration of the six-dimensional potential over the Q1,Q2 and Q3 coordinates.Each potential has a planar T-shaped global minimum,a planar local minimum,two inplane saddle points as well as an out-plane saddle point.The global minimum is located at R=3.46A,θ=109.9° andφ=0.0° with a well depth of 35.301 cm^-1.The radial discrete variable representation/angular finite basis representation method and the Lanczos algorithm were employed to calculate the rovibrational energy levels.The calculated band origins are blue-shifted(0.025 cm^-1 and 0.031 cm^-1)and(0.041 cm^-1 and 0.060 cm^-1)for He-(paraH2S)and He-(ortho-H2S)in theν2 andν3 region of the H2S molecule,respectively.
文摘In this paper,we introduce a special class of nilpotent Lie groups defined by hermitian maps,which includes all the groups of affine holomorphic automorphisims of Siegel domains of type Ⅱ,in particular,the Heisenberg group.And we study harmonic analysis on these groups as spectral theory of the associated Sub-Laplacian instead of the group representation theory in usual way.
