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Controllability of probabilistic Boolean control networks with time-variant delays in states

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Science China(Information Sciences) 2016年第9期59卷 131-140页

作者： Kuize zhang lijun zhang College of Automation Harbin Engineering University Institute of Systems Science Chinese Academy of Sciences School of Marine Science and Technology Northwestern Polytechnical University

This paper investigates the controllability of probabilistic Boolean control networks(PBCNs) with time-variant delays in states. By cutting the time sequence, we split the network into at most countably infinitely many subnetworks with no delays, where any one of the longest subnetworks is called a controllability constructed path(CCP). When the CCP is of infinite length, we prove that the network is controllable iff any CCP is controllable, and give an equivalent condition for the controllability of the network. When it is of finite length, we give a necessary condition and a sufficient condition for the controllability of the network, and show that the controllability of the network is not equivalent to the controllability of a CCP.

关键词： probabilistic Boolean control network time delay controllability constructed path semi-tensor product of matrices controllability

Performance of Ni-Cu bimetallic co-catalyst g-C3N4 nanosheets for improving hydrogen evolution

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Journal of Materials Science & Technology 2020年第14期47卷 144-156页

作者： Zhiliang Jin lijun zhang School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China Ningxia Key Laboratory of Solar Chemical Conversion Technology North Minzu UniversityYinchuan 750021China Key Laboratory for Chemical Engineering and Technology State Ethnic Affairs CommissionNorth Minzu UniversityYinchuan 750021China

The Ni-Cu bimetallic nanoparticles were successfully anchorred on the surface of g-C3N4 nanosheets by a simple heat treatment process which was applied to the photocatalytic hydrogen evolution *** introduction of Ni-Cu could significantly improve the photocatalytic hydrogen evolution performance compared with pure g-C3N4 in the system sensitized by eosin Y under a visible irradiation *** hydrogen production activity of the composite reached 104.4μmol(2088.28μmol g^-1 h^-1)after using the Ni Cu double promoter strategy,which was 24.3 times higher than *** excellent electrical conductivity of the bimetallic Ni-Cu and the close interfacial contact between Ni Cu and g-C3N4 played an important role for increasing the charge transfer *** were also the reasons of more efficient charge separation,which ultimately led to a significant promotion on the photocatalytic hydrogen production ***-Cu/g-C3N4 coupling with a close Schottky interface between metal and semiconductor which enhanced H2-evolution performance and TEOA oxidation *** work provided a new way to load Ni Cu bimetallic nanoparticles in situ onto g-C3N4 and a reference on relative semiconductor materials.

关键词： Bimetallic Ni-Cu g-C3N4 Charge separation Hydrogen evolution

Optical emission enhancement of bent InSe thin films

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Science China(Information Sciences) 2021年第4期64卷 149-156页

作者： Jiahao XIE lijun zhang State Key Laboratory of Integrated Optoelectronics Key Laboratory of Automobile Materials of MOESchool of Materials Science and Engineering Jilin University

In contrast to the majority of two-dimensional semiconductors such as transition metal dichalcogenides, indium selenide(InSe) possesses an intrinsic large out-of-plane oriented band-edge luminescent dipole. This unique anisotropic feature of band-edge optical emissions can be exploited to achieve enhanced optical signal in bent regions of materials created by geometrical modification. We herein investigate based on first-principle calculations the mechanism of this optical emission enhancement by modelling the photoluminescence processes in bent and flat regions of the InSe thin film. We propose in our model that the shorter-wavelength interband transition, labelled as transition B′, between the second-highest valence band and the bottom of conduction band plays an important role in the enhancing process. Our model robustly describes the dependence of optical emission enhancement in the bent InSe thin films on thickness, incident light orientation, and excitation photon energy. In particular, we found that when excitation photon energy is lower than the energy of transition B′, strong enhancement up to hundreds of times can be obtained by applying an incident light at an angle less than 70° to the InSe layers. Our results provide useful references for modulating luminescent properties of InSe films toward flexible optoelectronic device applications.

关键词： InSe enhanced luminescence 2D semiconductor optical transition optical anisotropy

Controllability of time-variant Boolean control networks and its application to Boolean control networks with finite memories

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Science China(Information Sciences) 2013年第10期56卷 239-250页

作者： zhang lijun zhang KuiZe College of Automation Harbin Engineering Univertsity Department of Mathematics University of Turku

This paper investigates the controllability of time-variant Boolean control networks(BCNs).For the time-variant BCNs,a necessary and sufcient condition for the controllability is given,and a control design algorithm is *** a BCN with fnite memories,an equivalent transformation to a time-variant BCN is *** a necessary and sufcient condition for the controllability and a control design algorithm are obtained.

关键词： time-variant Boolean control network Boolean control network with fnite memories semi-tensor product of matrices controllability

Quantitative phase-field simulation of the entire solidification process in one hypereutectic Al–Si alloy considering the effect of latent heat

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Progress in Natural Science:Materials International 2021年第3期31卷 428-433页

作者： Kai Wang lijun zhang Institute for Energy and Climate Research IEK-2 Forschungszentrum Jülich State Key Laboratory of Power Metallurgy Central South University

The multi-phase-field(MPF) model coupled with reliable CALPHAD thermodynamic/atomic mobility descriptions, appropriate faceted anisotropy and key experimental validation is employed to perform the quantitative simulation of the microstructure evolution of the hypereutectic Al-16 wt%Si alloy during solidification. By considering the effect of latent heat released during the eutectic phase transformation in the simulation, the appropriate entire solidification sequence is obtained. All the characteristics in the as-cast microstructure can be nicely reproduced, including the primary(Si) encircled by the second primary(Al) halo, and the coupled eutectic grains appearing at the Liquid/(Al) interface rather than Liquid/(Si) interface. Moreover, three types of growth patterns of eutectic(Si) with different lengths are distinguished according to the distance between primary(Si)and the nucleation position of eutectic(Si). Furthermore, the evaluated ratios of width to length for 50 eutectic(Si) grains due to the MPF simulation are in good agreement with the experimental data. The quantitative phasefield simulation of the entire solidification process of the hypereutectic Al-16 wt%Si alloy in the present work is anticipated to pave the way for revealing the grain refinement mechanism in hypereutectic Al–Si alloys in the future studies.

关键词： Al–Si hypereutectic Alloy Solidification Phase-field simulation Latent heat Eutectic (Si)

Large-Sized Ankylosaur(Dinosauria) from the Lower Cretaceous Jiufotang Formation of Western Liaoning,China

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Acta Geologica Sinica(English Edition) 2014年第4期88卷 1060-1065页

作者： JI Shu-an zhang lijun zhang Shudong zhang lijun 1 JIANG Shan Institute of Geology Chinese Academy of Geological Sciences Key Laboratory of Stratigraphy andPaleontology Ministry of Land and Resources Beijing 100037 China Administration Bureau of Fossil Resource Protection of Liaoning Province Shenyang 110032 Liaoning China Administration Branch of Fossil Protection Bureau of Land and Resources of Kazuo County Kazuo122300 Liaoning China Shenyang Center of the China Geological Survey Shenyang 110034 Liaoning China

Two incomplete bones referred to ankylosaur scapulocoracoid and humerus are described, which were discovered from the Early Cretaceous Jiufotang Formation of Dachengzi Town, Kazuo County, Liaoning Province. Ankylosaur dinosaurs have ever been found in the Lower Cretaceous Yixian, Fuxin and Sunjiawan Formations of western Liaoning. The occurrence of ankylosaurs within Jiufotang Formation improves our knowledge on the ankylosaur stratigraphic distribution. Based on the length of scapulocoracoid, the new dinosaur is estimated to exceed 6.0 meters long, representing the largest ankylosaur in western Liaoning.

关键词： Kazuo County Liaoning Province Lower Cretaceous Jiufotang Formation Ankylosauria

Matching Algorithms of Minimum Input Selection for Structural Controllability Based on Semi-Tensor Product of Matrices

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Journal of Systems Science & Complexity 2022年第5期35卷 1808-1823页

作者： FAN Naqi zhang lijun zhang Shenggui LIU Jiuqiang College of Intelligent Systems Science and Engineering Harbin Engineering UniversityHarbin 150001China School of Marine Technology Northwestern Polytechnical UniversityXi'an 710072China School of Mathematics and Statistics Northwestern Polytechnical UniversityXi'an 710129China College of Big Data Statistics Guizhou University of Finance and EconomicsGuiyang 550025China

In 2011,Liu,et *** the structural controllability of directed *** proved that the minimum number of input signals,driver nodes,can be determined by seeking a maximum matching in the directed ***,the algorithm for seeking a maximum matching is the key to solving the structural controllability problem of directed *** this study,the authors provide algebraic expressions for matchings and maximum matchings proposed by Liu,et al.(2011)via a new matrix product called semi-tensor product,based on which the corresponding algorithms are established to seek matchings and maximum matchings in digraphs,which make determining the number of driver nodes tractable in *** addition,according to the proposed algorithm,the authors also construct an algorithm to distinguish critical arcs,redundant arcs and ordinary arcs of the directed network,which plays an important role in studying the robust control *** example of a small network from Liu’s paper is used for algorithm verification.

关键词： Digraph directed network maximum matching semi-tensor product of matrices structural controllability

Construction of Type-II QC LDPC Codes Based on Perfect Cyclic Difference Set

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Chinese Journal of Electronics 2015年第1期24卷 146-151页

作者： zhang lijun LI Bing CHENG Leelung School of Electronic and Information Engineering Beijing Jiaotong University Space Star Technology Co. Ltd China Academy of Space Technology Department of Electronic Engineering City University of Hong Kong

Quasi-cyclic(QC) Low-density paritycheck(LDPC) codes are constructed from combination of weight-0(null matrix) and Weight-2(W2) Circulant matrix(CM), which can be seen as a special case of the general type-II QC LDPC codes. The shift matrix of the codes is built on the basis of one integer sequence, called perfect Cyclic difference set(CDS), which guarantees the girth of the code at least six. Simulation results show that the codes can perform well in comparison with a variety of other LDPC codes. They have excellent error floor and decoding convergence characteristics.

关键词： Type-II QC LDPC codes Weight-2 circulant matrix Perfect cyclic difference sets.

Automation of diffusion database development in multicomponent alloys from large number of experimental composition profiles

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npj Computational Materials 2021年第1期7卷 320-332页

作者： Jing Zhong Li Chen lijun zhang State Key Laboratory of Powder Metallurgy Central South UniversityChangshaHunanChina Shenzhen Research Institute Central South UniversityShenzhenChina

Nowadays,the urgency for the high-quality interdiffusion coefficients and atomic mobilities with quantified uncertainties in multicomponent/multi-principal element alloys,which are indispensable for comprehensive understanding of the diffusioncontrolled processes during their preparation and service periods,is merging as a momentous trending in materials ***,the traditional exploration approach for database development relies heavily on expertize and labor-intensive computation,and is thus intractable for complex *** this paper,we augmented the HitDIC(high-throughput determination of interdiffusion coefficients,https://***)software into a computation framework for automatic and efficient extraction of interdiffusion coefficients and development of atomic mobility database directly from large number of experimental composition *** an efficient framework proceeds in a workflow of automation concerning techniques of data-cleaning,feature engineering,regularization,uncertainty quantification and parallelism,for sake of agilely establishing high-quality kinetic database for target *** of the developed infrastructures was finally conducted in fcc CoCrFeMnNi high-entropy alloys with a dataset of 170 diffusion couples and 34,000 composition points for verifying their reliability and *** investigation over the obtained kinetic descriptions indicated that the sluggish diffusion is merely unilateral interpretation over specific composition and temperature ranges affiliated to limited *** is inferred that data-mining over large number of experimental data with the combinatorial infrastructures are superior to reveal extremely complex composition-and temperature-dependent thermal–physical properties.

关键词： alloys diffusion database