To increase accuracy of navigation parameters,a perspective measuring complex with intellectual components is developed.Conception of synthesis optimal structure of the measuring complex is realized basing on a select...To increase accuracy of navigation parameters,a perspective measuring complex with intellectual components is developed.Conception of synthesis optimal structure of the measuring complex is realized basing on a selective method using principles of the functional systems.Selection of measured information is finished by original numeric criterion of observation level of state vector components.Prediction is realized by algorithm of self-organization that makes synthesis of the optimal complication.Therefore mechanism of self-regulation is realized and accuracy of the selective navigation complex is increased.展开更多
Air traffic complexity is an objective metric for evaluating the operational condition of the airspace. It has several applications, such as airspace design and traffic flow management.Therefore, identifying a reliabl...Air traffic complexity is an objective metric for evaluating the operational condition of the airspace. It has several applications, such as airspace design and traffic flow management.Therefore, identifying a reliable method to accurately measure traffic complexity is important. Considering that many factors correlate with traffic complexity in complicated nonlinear ways,researchers have proposed several complexity evaluation methods based on machine learning models which were trained with large samples. However, the high cost of sample collection usually results in limited training set. In this paper, an ensemble learning model is proposed for measuring air traffic complexity within a sector based on small samples. To exploit the classification information within each factor, multiple diverse factor subsets(FSSs) are generated under guidance from factor noise and independence analysis. Then, a base complexity evaluator is built corresponding to each FSS. The final complexity evaluation result is obtained by integrating all results from the base evaluators. Experimental studies using real-world air traffic operation data demonstrate the advantages of our model for small-sample-based traffic complexity evaluation over other stateof-the-art methods.展开更多
The metal-organic framework(MOF){[Cu(L1)_(0.5)(CN)]·4H_2O·3DMSO}_n(1) was assembled by 1,4-bis(3?,5?-dicyano-2?,6?-di(pyrid-4-yl)-1?,4?-dihydropyridyl)benzene(L1) together with copper c...The metal-organic framework(MOF){[Cu(L1)_(0.5)(CN)]·4H_2O·3DMSO}_n(1) was assembled by 1,4-bis(3?,5?-dicyano-2?,6?-di(pyrid-4-yl)-1?,4?-dihydropyridyl)benzene(L1) together with copper cyanide at room temperature. In 1,the Cu~+ ions are linked by CN-anions into a 1D helical chain,which is further fused together by tetradentate L1 ligands to build an extended 3D porous framework with two different types of functionalized channels. 1 crystallizes in the monoclinic,space group P21/c with a = 17.8729(6),b = 8.7298(3),c = 22.7524(9) ?,β = 96.072(4)o,V = 3530.1(2) ?~3,μ = 0.845 mm-1,Dc = 1.352 Mg/m^3,Z = 4,Mr = 718.35,F(000) = 1500,S = 1.081,the final R = 0.0877 and wR = 0.2275 for 6975 observed reflections with I 〉 2σ(I).展开更多
The reaction of the reduced Schiff base HL(N-(4-hydroxybenzyl)-L-serine) with Zn(CH3COO)2·2H2O in aqueous solution afforded [Zn(L)2]·3H2O(I). The complex has been characterized by elemental analysi...The reaction of the reduced Schiff base HL(N-(4-hydroxybenzyl)-L-serine) with Zn(CH3COO)2·2H2O in aqueous solution afforded [Zn(L)2]·3H2O(I). The complex has been characterized by elemental analysis, FT-IR, powder X-ray diffraction, electrospray ionization mass spectrometry and single-crystal X-ray diffraction. Complex I crystallizes in the orthorhombic system, space group P212121, with a=9.197(2), b=10.445(2), c=24.149(5) , V=2319.8(8) 3, Z=4, C(20)H(30)N2O11 Zn, Mr=539.83, Dc=1.546 g·cm3, μ=1.122 mm(-1), F(000)=1128, GOOF=0.971, the final R=0.0206 and w R=0.0506 for 4346 observed reflections(I > 2σ(I)). In complex I, each Zn(II) ion coordinates with three carboxyl oxygen atoms and two amine nitrogen atoms from three L-anions, forming a distorted five-coordinated trigonal bipyramidal geometry. Complex I exhibits a 1D wavy chain structure that is extended by hydrogen-bonding interactions to form a supramolecular network. The bioactivity of the complex as a potential PTPs inhibitor in vitro was investigated, displaying potent inhibition against PTP1B(IC(50), 0.24 μM) and TCPTP(IC(50), 0.53 μM) with a moderate selectivity.展开更多
In materials science,data-driven methods accelerate material discovery and optimization while reducing costs and improving success rates.Symbolic regression is a key to extracting material descriptors from large datas...In materials science,data-driven methods accelerate material discovery and optimization while reducing costs and improving success rates.Symbolic regression is a key to extracting material descriptors from large datasets,in particular the Sure Independence Screening and Sparsifying Operator(SISSO)method.While SISSO needs to store the entire expression space to impose heavy memory demands,it limits the performance in complex problems.To address this issue,we propose a RF-SISSO algorithm by combining Random Forests(RF)with SISSO.In this algorithm,the Random Forests algorithm is used for prescreening,capturing non-linear relationships and improving feature selection,which may enhance the quality of the input data and boost the accuracy and efficiency on regression and classification tasks.For a testing on the SISSO’s verification problem for 299 materials,RF-SISSO demonstrates its robust performance and high accuracy.RF-SISSO can maintain the testing accuracy above 0.9 across all four training sample sizes and significantly enhancing regression efficiency,especially in training subsets with smaller sample sizes.For the training subset with 45 samples,the efficiency of RF-SISSO was 265 times higher than that of original SISSO.As collecting large datasets would be both costly and time-consuming in the practical experiments,it is thus believed that RF-SISSO may benefit scientific researches by offering a high predicting accuracy with limited data efficiently.展开更多
The complexation of alkyl-substituted pillar[5]arenes with primary ammonium salts is investigated. 1,4-Bis- (methoxy)pillar[5]arene (MeP5) can form strong complexes with the primary ammonium salts in CDC13. Howeve...The complexation of alkyl-substituted pillar[5]arenes with primary ammonium salts is investigated. 1,4-Bis- (methoxy)pillar[5]arene (MeP5) can form strong complexes with the primary ammonium salts in CDC13. However, 1,4-bis(ethoxy)pillar[5]arene (EtP5) shows weak interaction with these vips, and 1,4-bis(butoxy)pillar[5]arene (BuP5) can not form such a complex at all. These results indicate that the modified alkyl chains of pillar[5]arene play an important role in the complexation selectivity.展开更多
A series of novel copillar[5]arenes 1a-1f containing different substituents were synthesized.And their com-plexation with two types of vips was investigated.For symmetrical vips,1,4-dibromobutane(DBB)could thread ...A series of novel copillar[5]arenes 1a-1f containing different substituents were synthesized.And their com-plexation with two types of vips was investigated.For symmetrical vips,1,4-dibromobutane(DBB)could thread in the cavity of copillar[5]arenes to form inclusion complexes.But for the unsymmetrical vips,copillar-[5]arene 1f bearing 4-(naphthalen-1-yloxy)butoxy could not complex with sec-butyl iodide(SBI)and sec-butyl bromide(SBB)at all,while 1f showed weak interaction with sec-butylamine•HCl(SBA)outside the cavity.These results indicated that the modified group of copillar[5]arene and the symmetry of vip played an important role in the complexation model and selectivity.展开更多
文摘To increase accuracy of navigation parameters,a perspective measuring complex with intellectual components is developed.Conception of synthesis optimal structure of the measuring complex is realized basing on a selective method using principles of the functional systems.Selection of measured information is finished by original numeric criterion of observation level of state vector components.Prediction is realized by algorithm of self-organization that makes synthesis of the optimal complication.Therefore mechanism of self-regulation is realized and accuracy of the selective navigation complex is increased.
基金co-supported by the State Key Program of National Natural Science Foundation of China (No. 91538204)the National Science Fund for Distinguished Young Scholars (No. 61425014)the National Key Technologies R&D Program of China (No. 2015BAG15B01)
文摘Air traffic complexity is an objective metric for evaluating the operational condition of the airspace. It has several applications, such as airspace design and traffic flow management.Therefore, identifying a reliable method to accurately measure traffic complexity is important. Considering that many factors correlate with traffic complexity in complicated nonlinear ways,researchers have proposed several complexity evaluation methods based on machine learning models which were trained with large samples. However, the high cost of sample collection usually results in limited training set. In this paper, an ensemble learning model is proposed for measuring air traffic complexity within a sector based on small samples. To exploit the classification information within each factor, multiple diverse factor subsets(FSSs) are generated under guidance from factor noise and independence analysis. Then, a base complexity evaluator is built corresponding to each FSS. The final complexity evaluation result is obtained by integrating all results from the base evaluators. Experimental studies using real-world air traffic operation data demonstrate the advantages of our model for small-sample-based traffic complexity evaluation over other stateof-the-art methods.
基金supported by the Natural Science Foundation of Fujian Province(2012J06006,2014J05026,2006L2005)
文摘The metal-organic framework(MOF){[Cu(L1)_(0.5)(CN)]·4H_2O·3DMSO}_n(1) was assembled by 1,4-bis(3?,5?-dicyano-2?,6?-di(pyrid-4-yl)-1?,4?-dihydropyridyl)benzene(L1) together with copper cyanide at room temperature. In 1,the Cu~+ ions are linked by CN-anions into a 1D helical chain,which is further fused together by tetradentate L1 ligands to build an extended 3D porous framework with two different types of functionalized channels. 1 crystallizes in the monoclinic,space group P21/c with a = 17.8729(6),b = 8.7298(3),c = 22.7524(9) ?,β = 96.072(4)o,V = 3530.1(2) ?~3,μ = 0.845 mm-1,Dc = 1.352 Mg/m^3,Z = 4,Mr = 718.35,F(000) = 1500,S = 1.081,the final R = 0.0877 and wR = 0.2275 for 6975 observed reflections with I 〉 2σ(I).
基金Supported by NNSFC(Nos.21271121,21471092,21571118)
文摘The reaction of the reduced Schiff base HL(N-(4-hydroxybenzyl)-L-serine) with Zn(CH3COO)2·2H2O in aqueous solution afforded [Zn(L)2]·3H2O(I). The complex has been characterized by elemental analysis, FT-IR, powder X-ray diffraction, electrospray ionization mass spectrometry and single-crystal X-ray diffraction. Complex I crystallizes in the orthorhombic system, space group P212121, with a=9.197(2), b=10.445(2), c=24.149(5) , V=2319.8(8) 3, Z=4, C(20)H(30)N2O11 Zn, Mr=539.83, Dc=1.546 g·cm3, μ=1.122 mm(-1), F(000)=1128, GOOF=0.971, the final R=0.0206 and w R=0.0506 for 4346 observed reflections(I > 2σ(I)). In complex I, each Zn(II) ion coordinates with three carboxyl oxygen atoms and two amine nitrogen atoms from three L-anions, forming a distorted five-coordinated trigonal bipyramidal geometry. Complex I exhibits a 1D wavy chain structure that is extended by hydrogen-bonding interactions to form a supramolecular network. The bioactivity of the complex as a potential PTPs inhibitor in vitro was investigated, displaying potent inhibition against PTP1B(IC(50), 0.24 μM) and TCPTP(IC(50), 0.53 μM) with a moderate selectivity.
基金supported by the National Natural Science Foundation of China(Nos.21933006 and 21773124)the Fundamental Research Funds for the Central Universities of Nankai University(Nos.63243091 and 63233001)the Supercomputing Center of Nankai University(NKSC).
文摘In materials science,data-driven methods accelerate material discovery and optimization while reducing costs and improving success rates.Symbolic regression is a key to extracting material descriptors from large datasets,in particular the Sure Independence Screening and Sparsifying Operator(SISSO)method.While SISSO needs to store the entire expression space to impose heavy memory demands,it limits the performance in complex problems.To address this issue,we propose a RF-SISSO algorithm by combining Random Forests(RF)with SISSO.In this algorithm,the Random Forests algorithm is used for prescreening,capturing non-linear relationships and improving feature selection,which may enhance the quality of the input data and boost the accuracy and efficiency on regression and classification tasks.For a testing on the SISSO’s verification problem for 299 materials,RF-SISSO demonstrates its robust performance and high accuracy.RF-SISSO can maintain the testing accuracy above 0.9 across all four training sample sizes and significantly enhancing regression efficiency,especially in training subsets with smaller sample sizes.For the training subset with 45 samples,the efficiency of RF-SISSO was 265 times higher than that of original SISSO.As collecting large datasets would be both costly and time-consuming in the practical experiments,it is thus believed that RF-SISSO may benefit scientific researches by offering a high predicting accuracy with limited data efficiently.
基金We are grateful to the National Natural Science Foundation of China,the Natural Science Foundation of Guangxi Province
文摘The complexation of alkyl-substituted pillar[5]arenes with primary ammonium salts is investigated. 1,4-Bis- (methoxy)pillar[5]arene (MeP5) can form strong complexes with the primary ammonium salts in CDC13. However, 1,4-bis(ethoxy)pillar[5]arene (EtP5) shows weak interaction with these vips, and 1,4-bis(butoxy)pillar[5]arene (BuP5) can not form such a complex at all. These results indicate that the modified alkyl chains of pillar[5]arene play an important role in the complexation selectivity.
基金the National Natural Science Foundation of China(No.21402033)the Guangxi Natural Science Foundation of China(No.2013GXNSFBA019033)+1 种基金the Guangxi Experiment Cen-tre of Science and Technology(No.YXKT2014009)the Scientific Research Foundation of Guangxi University(No.XBZ130017).
文摘A series of novel copillar[5]arenes 1a-1f containing different substituents were synthesized.And their com-plexation with two types of vips was investigated.For symmetrical vips,1,4-dibromobutane(DBB)could thread in the cavity of copillar[5]arenes to form inclusion complexes.But for the unsymmetrical vips,copillar-[5]arene 1f bearing 4-(naphthalen-1-yloxy)butoxy could not complex with sec-butyl iodide(SBI)and sec-butyl bromide(SBB)at all,while 1f showed weak interaction with sec-butylamine•HCl(SBA)outside the cavity.These results indicated that the modified group of copillar[5]arene and the symmetry of vip played an important role in the complexation model and selectivity.