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Bifurcation control of a fractional-order delayed competition and cooperation model of two enterprises

Science China(Technological Sciences) 2019年第12期62卷 2130-2143页

作者： XU ChangJin liao MaoXin li PeiLuan Guizhou Key Laboratory of Economics System Simulation Guizhou University of Finance and EconomicsGuiyang 50004China School of Mathematics and Physics University of Souh ChinaHengyang 421001China School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang 471023China

The competition and cooperation among enterprises has become a hot topic and focus issue in today’s world. How to manage the enterprise well so as to achieve the maximum output is an important problem for enterprise managers. Optimizing output of two enterprises plays a key role in operating enterprises. Many scholars pay much attention to this aspect. However, the reports on the stability and Hopf bifurcation for fractional-order delayed competition and cooperation model of two enterprises are very few. This paper is concerned with the stability, the existence of Hopf bifurcation and the bifurcation control issue of fractionalorder delayed competition and cooperation model of two enterprises. Firstly, some new sufficient conditions that guarantee the stability and the existence of Hopf bifurcation for fractional-order delayed competition and cooperation model of two enterprises are obtained by regarding the delay as bifurcation parameter. Then a suitable time delayed feedback controller is designed to control the Hopf bifurcation for involved model. The study shows that the delay and the fractional order have an important effect on the stability and Hopf bifurcation of involved model. Some simulations justifying the validity of the derived analytical results are given. At last, we end this paper with a concise conclusion. The obtained results of this article are innovative and are of great significance in handling the competition and cooperation among enterprises.

关键词： bifurcation control competition and cooperation model enterprise stability hopf bifurcation fractional order delay

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A MAPLE PACKAGE OF AUTOMATED DERIVATION OF HOMOTOPY ANALYSIS SOLUTION FOR PERIODIC NONliNEAR OSCILLATIONS

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Journal of Systems Science & Complexity 2012年第3期25卷 594-616页

作者： Yinping liU Shijun liao Zhibin li Department of Computer Science and Technology East China Normal University State Key Lab of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringDepartment of MathematicsShanghai Jiaotong University Department of Computer Science East China Normal University

Based on the homotopy analysis method, a general analytic technique for strongly nonlinear problems, a Maple package of automated derivation （ADHO） for periodic nonlinear oscillation systems is presented. This Maple package is valid for periodic oscillation systems in rather general, and can automatically deliver the accurate approximations of the frequency co and the mean of motion δof a nonlinear periodic oscillator. Based on the homotopy analysis method which is valid even for highly nonlinear problems, this Maple package can give accurate approximate expressions even for nonlinear oscillation systems with strong nonlinearity. Besides, the package is user-friendly： One just needs to input a governing equation and initial conditions, and then gets satisfied analytic approximations in few seconds. Several different types of examples are given in this paper to illustrate the validity of this Maple package. Such kind of package provides us a helpful and easy-to-use tool in science and engineering to analyze periodic of this Maple package from the is published publicly. nonlinear oscillations. And it is free address http：//*** to download the electronic version ***/*** once the paper

关键词： Automated derivation homotopy analysis method homotopy Pade technique nonlinear oscillation Wu's elimination method.

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Automatic differentiation for reduced sequential quadratic programming

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Journal of Systems Engineering and Electronics 2007年第1期18卷 57-62页

作者： liao liangcai li Jin Tan Yuejin School of Information System & Management National Univ. of Defense Technology Changsha 410073 P. R. China The Fifth Inst. of the Missile Army Beijing 100085 P. R. China

In order to slove the large-scale nonlinear programming （NLP） problems efficiently, an efficient optimization algorithm based on reduced sequential quadratic programming （rSQP） and automatic differentiation （AD） is presented in this paper. With the characteristics of sparseness, relatively low degrees of freedom and equality constraints utilized, the nonlinear programming problem is solved by improved rSQP solver. In the solving process, AD technology is used to obtain accurate gradient information. The numerical results show that the combined algorithm, which is suitable for large-scale process optimization problems, can calculate more efficiently than rSQP itself.

关键词： Automatic differentiation Reduced sequential quadratic programming Optimization algorithm

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Synthesis, Characterization, and Catalytic Ethylene Oligomerization of Pyridine-imine Palladium Complexes

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Chinese Journal of Polymer Science 2018年第2期36卷 176-184页

作者： Xiao-lin Chen Jie Gao Heng liao hai-Yang Gao Qing Wu School of Materials Science and Engineering Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education Guangdong Laboratory of High-performance Polymer Composites Sun Yat-sen University

Two neutral five-membered pyridine-imine palladium complexes with the bulky dibenzhydryl（CH（Ph）2） substituted aniline were synthesized and fully characterized by nuclear magnetic resonance（NMR） and X-ray crystal diffraction. Well-defined cationic palladium complexes were further obtained by treatment of chloromethylpalladium complexes with sodium tetrakis（3,5-bis（trifluoromethyl）phenyl）borate（NaBArF） in CH3CN. Cationic palladium complexes were capable of catalyzing ethylene oligomerization without any cocatalysts. The influences of catalyst structure, reaction temperature, and ethylene pressure on ethylene oligomerization were studied in detail. The introduction of bulky benzhydryl（CH（Ph）2） on the ortho position of the aniline moiety enhanced catalytic activity, thermal stability of the catalyst, and molecular weight of the obtained products. Highly branched oligomers with molecular weights of 600-800 g/mol and narrow polydispersities（1.03-1.12） were produced.

关键词： Palladium Ethylene Oligomerization Branching

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An effective framework for asynchronous incremental graph processing

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Frontiers of Computer Science 2019年第3期13卷 539-551页

作者： Xinqiao LV Wei XIAO Yu ZHANG Xiaofei liao hai JIN Qiangsheng HUA Service Computing Technology and System Lab Cluster and Grid Computing Lab School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

Although many graph processing systems have been proposed, graphs in the real-world are often dynamic. It is important to keep the results of graph computation up-todate. Incremental computation is demonstrated to be an efficient solution to update calculated results. Recently, many incremental graph processing systems have been proposed to handle dynamic graphs in an asynchronous way and are able to achieve better performance than those processed in a synchronous way. However, these solutions still suffer from sub-optimal convergence speed due to their slow propagation of important vertex state (important to convergence speed) and poor locality. In order to solve these problems, we propose a novel graph processing framework. It introduces a dynamic partition method to gather the important vertices for high locality, and then uses a priority-based scheduling algorithm to assign them with a higher priority for an effective processing order. By such means, it is able to reduce the number of updates and increase the locality, thereby reducing the convergence time. Experimental results show that our method reduces the number of updates by 30%, and reduces the total execution time by 35%, compared with state-of-the-art systems.

关键词： incremental computation graph processing iterative computation asynchronous convergence

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Photoswitchable Spiropyridine Enabled Photoactuation of Polymeric Hydrogels under Physiological pH Conditions

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Chinese Journal of Polymer Science 2024年第10期42卷 1602-1609,I0015页

作者： Cong liao Meng-Qi Du Chuang li Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaAnhui230026China

The incorporation of molecular switches into polymer networks has been a powerful approach for the development of functional polymer materials that display macroscopic actuation and function enabled directly by molecular ***,such materials sometimes require harsh conditions to perform their functions,and the design of new molecular photoswitches that can function under physiological conditions is highly ***,we report the design and synthesis of a spiropyridine-based photoswitchable hydrogel that exhibits light-driven actuation at physiological *** to its high p Ka,spiropyridine maintains its ring-open protonated form at neutral pH,and the resulting hydrogel remains in a swollen *** irradiation with visible light,the ring closure of spiropyridine leads to a decrease in the charge and a reduction in the volume of the *** contracted gel could spontaneously recover to its expanding state in the dark,and this process is highly dynamic and reversible when the light is switched on and ***,the hydrogel shows switchable fluorescence in response to visible *** deformation is observed in the hydrogel thin films upon irradiation from one ***,the independence of this spiropyridine hydrogel from the acidic environment makes it biotolerant and shows excellent *** biocompatible spiropyridine hydrogel might have important biorelated applications in the future.

关键词： Spiropyridine photowitch Polymer hydrogel Photoactuation Physiological pH Biocompatibility

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Relationship between stand characteristics and soil properties of two typical forest plantations in the mountainous area of Western Sichuan, China

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Journal of Mountain Science 2019年第8期16卷 1816-1832页

作者： YANG Hao MIAO Ning li Shao-cai MA Rui liao Zi-yan WANG Wei-ping SUN hai-long Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China

There is uncertainty and limited knowledge regarding stand characteristics and soil properties of middle-aged pure forest plantations in the mountainous area of Western Sichuan. Plantation forests are almost exclusively planted as monocultures in the Pengzhou forest farm in the western mountainous area of Sichuan Province. This study aimed to assess the spatial and ecological characteristics of middle-aged Cunninghamia lanceolata(Lamb.) Hook. and Cryptomeria fortunei Hooibr. in the Pengzhou forest farm. The relationships and differences between stand growth characteristics and forest soil composition were assessed on the two forests planted simultaneously within the same area and exposed to the same environmental conditions. Cr. fortunei grew sparse, and slower than Cun. lanceolata. Principal component analysis indicated that the soil properties in the Cr. fortunei plantation were better than those in the Cun. lanceolata plantation. Redundancy analysis revealed that the differences in stand structure were affected significantly by the total nitrogen content and pH value. Thus, we propose that Cr. fortunei is planted for priority consideration in the subtropical high mountain area. Further, tending operations and application of fertilizers need to be conducted in Cun. lanceolata forests. Based on theoretical and experimental data, the present study explains why local farmers are more willing to plant Cr. fortunei, and thus provides a useful theoretical reference for the development of sustainable plantations in the future.

关键词： Planted forest Stand structure Soil properties Cunninghamia lanceolata Cryptomeria fortunei Pioneer tree

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Numerical studies of dynamic behavior of liquid film on single-layer wire mesh with different wettabilities

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Frontiers of Chemical Science and Engineering 2022年第11期16卷 1672-1680页

作者： hai-Long liao Lan Jiang hai-Xin Yu Zhi-Hao liu Ji-Wen Fu Guang-Wen Chu Yong Luo State Key Laboratory of Organic–Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China

Droplet impacting on the stainless steel wire mesh is very common in chemical devices,like a rotating packed *** wettability of wire mesh significantly affects the liquid flow pattern and liquid dispersion ***,the effect of surface wettability on the impaction phenomena at microscale such as liquid film is still *** this work,the dynamic behavior of liquid film on the surface of wire mesh was analyzed by computational fluid dynamics *** dynamic behavior of liquid film on the surface of wire mesh can be divided into the following three steps:(1)spreading step;(2)shrinkage process;(3)stabilizing or disappearing *** of surface wettability,as well as operating conditions,on wetting area and liquid film thickness were *** to the hydrophilic wire mesh,the final wetting area of hydrophobic wire mesh is zero in most *** average liquid film thickness on the surface of hydrophilic wire mesh is 30.02–77.29μm,and that of hydrophobic wire mesh is 41.76–237.37μ*** work provided a basic understanding of liquid film flow at microscale on the surface with various surface wettabilities,which can be guiding the packing optimization and design.

关键词： stainless steel wire mesh computational fluid dynamics surface wettability liquid film impacting

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Effect of width on the properties of Faraday waves in Hele-Shaw cells

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Science China(Physics,Mechanics & Astronomy) 2019年第7期62卷 89-94页

作者： XiaoChen li Jing li XiaoMing li ShiJun liao ChaoHe Chen School of Civil Engineering and Transportation South China University of Technology State Key Laboratory of Ocean Engineering School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University

The effect of container geometry on the Faraday waves in Hele-Shaw cells has been investigated. The wave heights increase with the width of the cell and a linear function is selected to express the relation between these data and parameters. The wave lengths also increase with the width and are in good agreement with the dispersion relation. In order to reveal the real nature behind these phenomena, we have developed a gap-averaged model to numerically solve this issue and give an analysis of the result to show how these Faraday waves are formed in a Hele-Shaw cell.

关键词： Faraday waves Hele-Shaw cell numerical simulation

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Role of the Radiative Effect of Black Carbon in Simulated PM_(2.5) Concentrations during a Haze Event in China

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Atmospheric and Oceanic Science Letters 2014年第5期7卷 434-440页

作者： liao li liao Hong State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC) Institute of Atmospheric Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The authors quantify the radiative effect of black carbon （BC） on simulated aerosol concentrations during the heavily polluted haze event of 11-14 January 2013 in northern China using the chemistry version of the Weather Research and Forecasting Model （WRF-Chem）. As a result of the stable synoptic conditions, simulated concentrations of BC and PM2.5 averaged over the study period were about 8-16 μg m-3 and 80-100 μg m-3, respectively, in the control simulation （CTRL）. When BC emissions were doubled （2BC）, tripled （3BC）, and quad- rupled （4BC） relative to the CTRL run, the simulated concentrations of aerosols in different regions showed distinct changes. The radiative effect of BC was simulated to increase concentrations of aerosols over Tianjin （Doml） and southern Henan （Dora3）, but to decrease in southern Hebei （Dora2）. Relative to the CTRL simulation, concen- trations of PM2s over Doml, Dom2, and Dom3 were simulated in 4BC to change by ＋18.6 1μg m-3 （＋32.3%）, -5.7 μg m 3 （-7.3%）, and ＋7.2 μg m3 （＋12.6%）, respec- tively. The BC-induced increases in aerosol concentra- tions corresponded mainly to the reductions in planetary boundary layer height over Doml and Dom3. The reduc- tions of aerosol concentrations in Dora2 were mainly caused by the weakened wind convergence at 850 hPa and reduced concentrations of sulfate and nitrate associ- ated with the reduced surface-layer ozone levels and rela- tive humidity.

关键词： aerosol black carbon PM2.5

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