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Optimal pivot path of the simplex method for linear programming based on reinforcement learning

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Science China Mathematics 2024年第6期67卷 1263-1286页

作者： Anqi li Tiande guo Congying Han Bonan li Haoran li School of Mathematical Sciences University of Chinese Academy of SciencesBeijing100049China

Based on the existing pivot rules,the simplex method for linear programming is not polynomial in the worst ***,the optimal pivot of the simplex method is *** this paper,we propose the optimal rule to find all the shortest pivot paths of the simplex method for linear programming problems based on Monte Carlo tree ***,we first propose the SimplexPseudoTree to transfer the simplex method into tree search mode while avoiding repeated basis ***,we propose four reinforcement learning models with two actions and two rewards to make the Monte Carlo tree search suitable for the simplex ***,we set a new action selection criterion to ameliorate the inaccurate evaluation in the initial *** is proved that when the number of vertices in the feasible region is C_(n)^(m),our method can generate all the shortest pivot paths,which is the polynomial of the number of *** addition,we experimentally validate that the proposed schedule can avoid unnecessary search and provide the optimal pivot ***,this method can provide the best pivot labels for all kinds of supervised learning methods to solve linear programming problems.

关键词： simplex method linear programming pivot rules reinforcement learning

Electrochemical Cascade Annulation for the Synthesis of 3-Sulfanylquinoline Derivatives under Mild Conditions

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Chinese Journal of Chemistry 2024年第16期42卷 1833-1838页

作者： Ke li Ming-Zhong guo Zhuo Chen Hao-Ran li Weisi guo Ming li lin-Bao Zhang State Key Laboratory Base of Eco-Chemical Engineering College of Chemistry and Molecular EngineeringQingdao University of Science&TechnologyQingdaoShandong 266042China

An efficient electrochemical approach has been developed for the construction of 3-sulfanylquinoline derivatives by treating phenylethynylbenzoxazinanones with disulfides in an undivided *** protocol provided a convenient route to functionalized quinolines with good functional group ***,it does not require any metal catalysts or additives,furnishing a series of biologicalquinolines inmoderatetogoodyields.

关键词： Electrocatalysis Electrooxidation Annulation 3-Sulfany quinoline C3-thioetherification

Semisymmetric Graphs of Order 2p^(3)with Valency p^(2)

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Algebra Colloquium 2024年第2期31卷 199-208页

作者： li Wang Songtao guo Genghua Fan School of Mathematics and Information Science Henan Polytechnic University JiaozuoHenan 454000China School of Mathematics and Statistics Henan University of Science and Technology LuoyangHenan 471023China 不详

A simple undirected regular graph is said to be semisymmetric if it is edge-transitive but not *** a semisymmetric graphΓof order 2p^(3),p a prime,it is well known thatΓis bipartite with two biparts having equal *** complete classification of such graphs has been given for the full automorphism group Aut(Γ)acting unfaithfully on at least one bipart ofΓ,which shows that there is only one infinite family of such graphs with valency p^(2).The graphs of this kind have been determined when Aut(Γ)acts faithfully and primitively on at least one bipart ofΓ,and thus there is only one remaining case for classifying such graphs of valency p^(2),Aut(Γ)acting faithfully and imprimitively on both biparts ofΓ,which is dealt with in this *** a result,there is only one infinite family of semisymmetric graphs of order 2p^(3)with valency p^(2).

关键词： semisymmetric graph semitransitive graph bi-coset graph

SCAB1 coordinates sequential Ca^(2+) and ABA signals during osmotic stress induced stomatal closure in Arabidopsis

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Science China(life Sciences) 2024年第1期67卷 1-18页

作者： Tianren Zhang li Bai Yan guo State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijing 100193China

Hyperosmotic stress caused by drought is a detrimental threat to plant growth and agricultural productivity due to limited water *** are gateways of transpiration and gas exchange,the swift adjustment of stomatal aperture has a strong influence on plant drought *** intensive investigations of stomatal closure during drought stress in past decades,little is known about how sequential signals are integrated during complete ***,we discovered that the rapid Ca^(2+) signaling and subsequent abscisic acid(ABA)signaling contribute to the kinetics of both F-actin reorganizations and stomatal closure in Arabidopsis thaliana,while STOMATAL CLOSURE-RELATED ACTIN BINDING PROTEIN1(SCAB1)is the molecular switch for this entire *** the early stage of osmotic shock responses,swift elevated calcium signaling promotes SCAB1 phosphorylation through calcium sensors CALCIUM DEPENDENT PROTEIN KINASE3(CPK3)and *** phosphorylation restrained the microfilament binding affinity of SCAB1,which bring about the Factin disassembly and stomatal closure *** the osmotic stress signal continued,both the kinase activity of CPK3 and the phosphorylation level of SCAB1 attenuated *** further found that ABA signaling is indispensable for these attenuations,which presumably contributed to the actin filament reassembly process as well as completion of stomatal ***,the dynamic changes of SCAB1 phosphorylation status are crucial for the kinetics of stomatal *** together,our results support a model in which SCAB1 works as a molecular switch,and directs the microfilament rearrangement through integrating the sequentially generated Ca^(2+) and ABA signals during osmotic stress induced stomatal closure.

关键词： calcium signal ABA stomatal movement microfilaments kinase

Heterobimetallic lanthanide tetrahedral cages:Synthesis,design and application for potential multimodal imaging contrast agent

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Journal of Rare Earths 2024年第2期42卷 278-285,I0002页

作者： Yongxiu li Feng guo Siwei Wei Duofu li Jun Zhang Kai Xu Dongping li Department of Chemistry Nanchang UniversityNanchang330031China Key Laboratory of Functional Molecule Design and Interface Process Anhui Jianzhu UniversityHefei230601China Department of Otolaryngology Head and Neck SurgeryThe Second Affiliated Hospital of Nanchang UniversityNanchang330006China

The construction and functionalization of lanthanide-organic cages have been a research hotspot in coordination *** from the unique luminescent and magnetic properties of lanthanide ions,the potential applications of lanthanide-organic cages in biological imaging applications are promising,but only a few corresponding explorations have been *** rein,we introduced a series of lanthanide tetrahedral cages,(Eu_(n)Gd_(4-n)L_(4))(sol)_8(n=0,1,2,3 and 4,where L=(4,4',4"-tris(4,4,4-trifluoro-1,3-dioxobutyl)-triphenylamine,and sol=dimethyl sulfoxide and methanol),with potential applications in biological *** the good luminescent and magnetic properties of Eu^(3+) and Gd^(3+) ions,Eu_(4)L_(4) and Gd_(4)L_(4) complexes show a high luminescence quantum yield of 29% in DMSO and large longitudinal relaxivity(r_(1)) of 11.4(mmol/L)^(-1)/s at 0.5 T in water containing 1 vol% DMSO,*** heterobimetallic Eu-Gd complexes achieve a dual imaging mode by combining luminescent and magnetic centers in one *** the Gd:Eu ratio increases from 1:3 to 3:1,the r_(1) values increases from 5.33 to 8.64(mmoI/L)^(-1)/s,higher than that of commercial contrast agent Gd-DOTA(3.23(mmol/L)^(-1)/s).Owing to their low toxicity and good cell imaging ability toward ECA 109 cells,the selfassembled Eu-Gd heterobimetallic tetrahedral cages could be potential candidates for the multimodal imaging contrast agent.

关键词： Lanthanide organic cage Luminescence Cell imaging Contrast agents Rare earths

Machine learning model based on non-convex penalized huberized-SVM

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Journal of Electronic Science and Technology 2024年第1期22卷 81-94页

作者： Peng Wang Ji guo lin-Feng li School of Finance and Economics Xizang Minzu UniversityXianyang712082China Research Center for Quality Development of Xizang Special Industries Xianyang712082China School of Computer Science and Technology Xinjiang UniversityUrumqi830017China

The support vector machine(SVM)is a classical machine learning *** the hinge loss and least absolute shrinkage and selection operator(LASSO)penalty are usually used in traditional ***,the hinge loss is not differentiable,and the LASSO penalty does not have the Oracle *** this paper,the huberized loss is combined with non-convex penalties to obtain a model that has the advantages of both the computational simplicity and the Oracle property,contributing to higher accuracy than traditional *** is experimentally demonstrated that the two non-convex huberized-SVM methods,smoothly clipped absolute deviation huberized-SVM(SCAD-HSVM)and minimax concave penalty huberized-SVM(MCP-HSVM),outperform the traditional SVM method in terms of the prediction accuracy and classifier *** are also superior in terms of variable selection,especially when there is a high linear correlation between the *** they are applied to the prediction of listed companies,the variables that can affect and predict financial distress are accurately filtered *** all the indicators,the indicators per share have the greatest influence while those of solvency have the weakest *** companies can assess the financial situation with the indicators screened by our algorithm and make an early warning of their possible financial distress in advance with higher precision.

关键词： Huberized loss Machine learning Non-convex penalties Support vector machine(SVM)

Viologen-based flexible electrochromic devices

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Journal of Energy Chemistry 2024年第6期93卷 453-470,I0012页

作者： Wenwen Wu Shanlu guo Jing Bian Xingyu He Haizeng li Jianmin li College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023JiangsuChina Department of Pathology College of MedicineUniversity of CincinnatiCincinnati 45221OhioUSA Optics and Thermal Radiation Research Center Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237ShandongChina

Electrochromic technology has gained significant attention in various fields such as displays,smart windows,biomedical monitoring,military camouflage,human-machine interaction,and electronic skin due to its ability to provide reversible and fast color changes under applied *** the rapid development and increasing demand for flexible electronics,flexible electrochromic devices(FECDs)that offer smarter and more controllable light modulation hold great promise for practical *** electrochromic material(ECM)undergoing color changes during the electrochemical reactions is one of the key components in electrochromic *** the ECMs,viologens,a family of organic small molecules with 1,1'-disubstituted-4,4'-dipyridinium salts,have garnered extensive research interest,due to their well-reversible redox reactions,excellent electron acceptance ability,and the ability to produce multiple ***,viologen-based FECDs demonstrate color changes in the liquid or semisolid electrolyte layer,eliminating the need for two solid electrodes and thus simplifying the device ***,viologens offer significant potential for the development of FECDs with high optical contrast,fast response speed,and excellent *** review aims to provide a comprehensive overview of the progress and perspectives of viologen-based *** begins by summarizing the typical structure and recent exciting developments in viologen-based FECDs,along with their advantages and ***,the review discusses recent advancements in FECDs with additional functionalities such as sensing,photochromism,and energy ***,the remaining challenges and potential research directions for the future of viologen-based FECDs are addressed.

关键词： Flexible electrochromic devices Optical modulation Viologens Flexible electronics Multifunctional devices Electrochromism

Multi-scale analyses of phase transformation mechanisms and hardness in linear friction welded Ti17(a+β)/Ti17(β)dissimilar titanium alloy joint

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Chinese Journal of Aeronautics 2024年第1期37卷 312-324页

作者： Zhenguo guo Tiejun MA Xiawei YANG Ju li Wenya li Achilles VAIRIS State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding TechnologiesNorthwestern Polytechnical UniversityXi’an 710072China Aeronautical Key Laboratory for Welding and Joining Technologies AVIC Manufacturing Technology InstituteBeijing 100024China Mechanical Engineering Department University of West AtticaAthens 12241Greece

The Ti17(a+β)-Ti17(β)dual alloy-dual property blisk produced using linear Friction Welding(LFW)is considered as high-performance component in advanced ***,up to now,microstructure evolution and relationship between microstructure and micro mechanical properties of LFWed Ti17(a+β)/Ti17(β)dissimilar joint have not been thoroughly *** this work,complex analyses of the phase transformation mechanisms of the joint are conducted,and phase transformations in individual zones are correlated to their microhardness and *** reveal that a dissolution occurs under high temperatures encountered during LFW,which reduces microhardness of the joint to that of Ti17(a+β)and Ti17(β).In ThermoMechanically Affected Zone of Ti17(a+β)(TMAZ-(a+β))side joint,a large number of nanocrystalline a phases form with different *** microstructure strengthens significantly by fine grains which balances partial softening effect of a dissolution,and increases nanohardness of a phase and microhardness of TMAZ-(a+β).Superlattice metastableβphase precipitates from metastableβin Weld Zone(WZ)during quick cooling following welding,because of short-range diffusion migration of solute atoms,especiallyβstabilizing elements Mo and *** precipitation of the superlattice metastableβphase results in precipitation strengthening,which in turn increases nanohardness of metastableβand microhardness in WZ.

关键词： linear friction welding Ti17 titanium alloy Phase transformation Microhardness Nanohardness

Engineering Ru（N^N）3-modified covalent organic framework for photocatalytic olefin epoxidation

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Science China Chemistry 2024年第11期67卷 3719-3728页

作者： Yan-lin li Sheng-li Huang guo-Yu Yang Key Laboratory of Cluster Science (Ministry of Education) Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical Engineering Beijing Institute of Technology

Photocatalytic olefin oxidation using air as an oxidant is an environmentally friendly method for producing epoxides. Covalent organic frameworks（COFs） have emerged as promising photocatalysts in various organic synthesis reactions. The combination of tri-（2-pyridinal aldehyde）-containing precursor with 4,4’,4’’-（1,3,5-triazine-2,4,6-triyl）trianiline generated（N^N）-I-COF. Via imine-to-quinoline transformation and coordination anchorage of Ru（N^N）3unit, Ru（N^N）3@Q-COF was obtained with improved chemical stability, skeleton conjugation, and novel photochemical characteristics, and demonstrated excellent photocatalytic activity in olefin epoxidation with a wide range of substrates. The presence of H2O played a crucial role in the formation of reactive oxygen species（ROSs）, which in turn influenced the olefin oxidation process. The hydrophilicity of Ru（N^N）3facilitated the approach of H2O and O2to the photogenerated charges, thereby promoting ROSs generation. The lipophilicity of Q-COF allowed for the absorption of olefin substrates, and its nano-channels increased encountering possibility between olefins and ROSs. Consequently, Ru（N^N）3@Q-COF provided an intriguing platform for olefin photooxidation and could be recycled multiple times without any degradation in performance. This report revealed that the conversion of classical ROSs into less potent oxidants with rapid kinetic rates played a crucial role in achieving highly efficient and selective epoxidation of terminal olefins.

关键词： polypyridyl Ru covalent organic framework olefin epoxidation photocatalysis