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Saliency detection of infrared image based on region covariance and global feature

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Journal of Systems Engineering and Electronics 2018年第3期29卷 483-490页

作者： LIU Songtao jiang ning LIU Zhenxing jiang Kanghui Department of Information Operation Dalian Naval Academy

In order to better represent infrared target features under different environments, a saliency detection method based on region covariance and global feature is proposed. Firstly, the region covariance features on different scale spaces and different image regions are extracted and transformed into sigma features,then combined with central position feature, the local salient map is generated. Next, a global salient map is generated by gray contrast and density estimation. Finally, the saliency detection result of infrared images is obtained by fusing the local and global salient maps. The experimental results show that the salient map of the proposed method has complete target features and obvious edges,and the proposed method is better than the state of art method both qualitatively and quantitatively.

关键词： saliency detection region covariance gray contrast density estimation

Analytical solution for the time-fractional heat conduction equation in spherical coordinate system by the method of variable separation

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Acta Mechanica Sinica 2011年第6期27卷 994-1000页

作者： Ting-Hui ning Xiao-Yun jiang School of Mathematics Shandong University 250100 Jinan China

In this paper,using the fractional Fourier law,we obtain the fractional heat conduction equation with a time-fractional derivative in the spherical coordinate *** method of variable separation is used to solve the timefractional heat conduction *** Caputo fractional derivative of the order 0 〈 α≤ 1 is *** solution is presented in terms of the Mittag-Leffler *** results are illustrated graphically for various values of fractional derivative.

关键词： Fractional Fourier law Fractional heat conduction equation - Spherical coordinate system - The separation of variables Mittag-Leffler function

Synthesis and Structural Characterization of a New Hydrogen-bonded Polyrotaxane of [Co(H_2O)_6]_(2+) with 1,1′-(Propane-1,3-diyl)dipyridinium-4-carboxylate

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Chinese Journal of Structural Chemistry 2006年第8期25卷 957-964页

作者： jiang ning-Yi LI Song-Lin Department of Chemistry College of Science Tianjin University Tianjin 300072 China

A new double betaine 1,1′-（propane-1,3-diyl）dipyridinium-4-carboxylate L has been synthesized. Reaction of 1, 1′-（propane-1,3-diyl）dipyridinium-4-carboxylate tetrahydrate 1 with Co（ClO4）2-6H2O leads to the formation of a new Co（Ⅱ） coordination compound, namely [Co（H2O）6]-2H2O-2L-2ClO4 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1. monoclinic, space group C2/c, a = 18.945（4）, b = 7.700（2）, c = l 1.888（2）A,β = 101.67（3）°, V = 1698.3（6） A^3, Z = 4, F（000） = 760.0, Dc = 1.402 g/cm^3, the final R = 0.0607 and wR = 0.1607 for 950 observed reflections （1 〉 2σ（I））; and those for 2： monoclinic, space group P21/c, a = 17.982（1）, b = 15.879 （1）, c = 7.0716（5）/A,β= 100.675（1）°, V= 1984.3（3） ,A^3 Z= 4, F（000） = 1010.0, Dc = 1.631 g/cm^3, the final R = 0.0316 and wR = 0.0896 for 3784 observed reflections （1 〉20（I））. Crystal structure analysis indicates that in 1, molecules of L in a ＂V-shaped＂ conformation are linked to chains sustained by O-H…O hydrogen bonds between carboxylate groups and solvent water molecules. The chains are joined by O-H…O and C-H…O hydrogen bonds to further expand into a three-dimensional structure. For 2, molecules of L in a ＂Z-shaped＂ conformation are linked by hydrogen bonds between carboxylate groups and aqua ligands to form a chain of loops running down the b axis. The （2D→2D） polythreading in compound 2 represents the mode of parallel interpenetration of 2D sheets, having polyrotaxane character.

关键词： 1,1′-(propane-1,3-diyl)dipyridinium-4-carboxylate polyrotaxane hydrogen bonding betaine derivative

Characterization and Crystal Structures of Two Copper(Ⅱ) Complexes Constructed by a Flexible Double Betaine Ligand

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Chinese Journal of Structural Chemistry 2007年第2期26卷 199-205页

作者： jiang ning-Yi LI Song-Lin Department of Chemistry College of Science Tianjin University Tianjin 300072 China

A flexible double betaine 1,4-bis（pyridinil-4-carboxylato）-1,4-dimethylbenzene L has been used to generate two Cu（Ⅱ）-containing metal complexes that exhibit different polymeric structures： [Cu（H2O）2 L].2NO3 1 and [Cu（H2O）3 L].2Cl.H2O 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1： triclinic, space group PT, a = 5.253（2）, b = 7.406（3）, c = 14.792（5） A, α = 84.195（5）, β = 80.014（5）, γ = 78.053（5）°, V= 553.2（3）A^3, Z = 1, F（000） = 293, Dc = 1.717 g/cm^3, the final R = 0.0385 and wR = 0.1079 for 1883 observed reflections （I 〉 2σ（I））; and those for 2： monoclinic, space group P21/c, a = 10.222（3）, b = 25.287（7）, c = 9.277（3）A, β = 93.572（5）°, V = 2393.2（12）A^3, Z = 4, F（000） = 1140, Dc = 1.540 g/cm^3, the final R = 0.0472 and wR = 0.0956 for 3204 observed reflections （I 〉2o（/））.

关键词： 1,4-bis(pyridinio-4-earboxylato)-l,4-dimethylbenzene copper(Ⅱ) complex double betaine

Seasonal Forecast of South China Sea Summer Monsoon Onset Disturbed by Cold Tongue La Niña in the Past Decade

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Advances in Atmospheric Sciences 2021年第1期38卷 147-155页

作者： ning jiang Congwen ZHU State Key Laboratory of Severe Weather and Institute of Climate System Chinese Academy of Meteorological SciencesBeijing 100081China

It has been suggested that a warm(cold)ENSO event in winter is mostly followed by a late(early)onset of the South China Sea(SCS)summer monsoon(SCSSM)in *** results show this positive relationship,which is mainly determined by their phase correlation,has been broken under recent rapid global warming since 2011,due to the disturbance of cold tongue(CT)La Niña *** from its canonical counterpart,a CT La Niña event is characterized by surface meridional wind divergences in the central-eastern equatorial Pacific,which can delay the SCSSM onset by enhanced convections in the warming Indian Ocean and the western subtropical *** to the increased Indian−western Pacific warming and the prevalent CT La Niña events,empirical seasonal forecasting of SCSSM onset based on ENSO may be challenged in the future.

关键词： monsoon onset SCSSM ENSO cold tongue La Niña seasonal forecast

Minimal Representations of Cuntz Algebras

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Acta Mathematica Sinica,English Series 2020年第7期36卷 749-764页

作者： Ling Juan YE Li ning jiang School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081P.R.China

Suppose that O_n(2 ≤ n ≤∞) is a Cuntz algebra. There exists a number 1 ≤ k(π, Ω) ≤∞such that if the cyclic representations(H, π, Ω) and(H, π, Ω) of the Cuntz algebra O_n are unitary equivalent, k(π, Ω) = k(π, Ω). Applying the number, one can define a minimal representation of O_n and give a sufficient condition of the minimality for a representation of O_n. Moreover, the relations between minimal states and minimal representations of Cuntz algebras and the relations between the minimality and the irreducibility of the representation of O_n are investigated, respectively.

关键词： algebra. O_n representation

The Galois Correspondence in Field Algebra of G-spin Model

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Acta Mathematica Sinica,English Series 2005年第4期21卷 673-680页

作者： Li ning jiang Mao Zheng GUO Department of Mathematics Beijing Institute of Technology Beijing 100081. P. R. China LMAM Department of Mathematics Peking University. Beijing 100871. P. R. China

Suppose that G is a finite group and D（G） the double algebra of G. For a given subgroup H of G, there is a sub-Hopf algebra D（G; H） of D（G）. This paper gives the concrete construction of a D（G; H）-invariant su... 详细信息

关键词： G-spin model Double algebra Observable algebra Galois closed

Initial alignment of compass based on genetic algorithm-particle swarm optimization

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Defence Technology（防务技术） 2020年第1期16卷 257-262页

作者： Yi-feng Liang Peng-fei jiang jiang-ning Xu Wen An Miao Wu College of Electrical Engineering Naval Univ.of EngineeringWuhan 430033China

The rapidity and accuracy of the initial alignment influence the performance of the strapdown inertial navigation system(SINS),compass alignment is one of the most important methods for initial *** selection of the parameters of the compass alignment loop directly affects the result of ***,the optimal parameters of the compass loop of different SINS are also different Traditionally,the alignment parameters are determined by experience and trial-and-error,thus it cannot ensure that the parameters are *** this paper,the Genetic Algorithm-Particle Swarm Optimization(GA-PSO) algorithm is proposed to optimize the compass alignment parameters so as to improve the performance of the initial alignment of strapdown *** experiment results showed that the GA-PSO algorithm can find out the optimal parameters of the compass alignment circuit quickly and accurately and proved the effectiveness of the proposed method.

关键词： Inertial alignment Genetic algorithm SINS Compass alignment

A preliminary study of impact of reduced system inertia in a low-carbon power system

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Journal of Modern Power Systems and Clean Energy 2015年第1期3卷 82-92页

作者： Di WU Milad JAVADI John ning jiang Electricity and Energy Reliability and Risk Laboratory School of Electrical and Computer EngineeringUniversity of OklahomaNormanOKUSA

One of the important features of low-carbon electric power system is the massive deployment of renewable energy resources in the advent of a new carbon-strained *** generation is a major technology of generating electric power with zero carbon dioxide *** a power system with the high penetration of wind generation,the displacement of conventional synchronous generators with variable speed wind turbines reduces system *** leads to larger system frequency deviation following a loss of large *** this paper,the impact of the reduction of system inertia on system frequency is analyzed as the result of the integration of a significant amount of wind generation into power ***,we present a preliminary study of the impact of the distribution of the inertia contributions from those online conventional synchronous generators on the rate of change of frequency(ROCOF)based on the total energy injected into the system due to the *** total fault energy is represented using Hamiltonian *** the IEEE 39-bus system,it is shown that for a fault with the given injected total energy,clearing time,and location,the distribution of inertia contributions can significantly affect the magnitude of ***,for such a fault with different locations,the average of the magnitudes of ROCOF caused by the fault at different locations is larger when the distribution of the inertia contributions is more dispersed.

关键词： Carbon dioxide emission Wind generation System inertia Rate of change of frequency