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Improved Approximation Schemes for Early Work Scheduling on Identical Parallel Machines with a Common Due date

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Journal of the Operations Research Society of China 2024年第2期12卷 341-350页

作者： wei-dong li School of Mathematics and Statistics Yunnan UniversityKunming650504YunnanChina

We study the early work scheduling problem on identical parallel machines in order to maximize the total early work,i.e.,the parts of non-preemptive jobs that are executed before a common due *** preprocessing and constructing an auxiliary instance which has several good properties,for any desired accuracy,we propose an efficient polynomial time approximation scheme with running time O(f(1/ε)n),where n is the number of jobs and f(1/ε)is exponential in 1/ε,and a fully polynomial time approximation scheme with running time O(1/ε^(2m+1)+n)when the number of machines is fixed.

关键词： Scheduling Early work Polynomial time approximation scheme Effcient polynomial time approximation scheme Fully polynomial time approximation scheme

Impact wear properties of dissimilar joints between bainitic frogs and pearlite rails

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Journal of Iron and Steel Research International 2024年第1期31卷 275-287页

作者： pin-yong Zeng Chun-guang Zuo Xiao-yu Zhang wei li Tribology Research Institute Southwest Jiaotong UniversityChengdu610031SichuanChina

The impact wear behavior and damage mechanism of dissimilar welded joints between U26Mn frog and U75 V rail before and after normalizing treatment were studied by cyclic impact *** experiment indicated that the impact wear volume of the joints increased with the increasing number of impact *** main wear mechanisms include pitting wear,mild fatigue wear,delamination wear,and fatigue wear,and plastic deformation was the primary impact wear *** them,fatigue wear had the greatest influence on wear volume,while other wear mechanisms had limited *** impact wear resistance of the base material was better than that of the heat-affected *** treatment was beneficial to improving the impact wear resistance of welded joints owing to its effect to promote pearlite recovery,grain refinement,and uniform distribution of *** martensite generated in the rail welded joints aggravated the impact wear damage to the materials,which should be avoided.

关键词： Dissimilar welded joint Impact wear Bainitic steel damage mechanism Wear rate

Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 445-454页

作者： li Yuchun Shen Chao liu wei li dong Department of Hydraulic Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this *** auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on *** parametric vibration equation is established for the test model using the finite-element *** auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent *** effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test *** with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental *** a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric *** with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed.

关键词： auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge

Seasonal response of nitrogen exchange fluxes to crab disturbance at sediment-water interface in coastal tidal wetlands

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Water Science and Engineering 2024年第2期17卷 129-138页

作者： Guo-fen Hua Shang-qing liu Xiang-dong liu jin-li li Yue Fang Wen-ting xie Xiang Xu College of Water Conservancy and Hydroelectric Power Hohai UniversityNanjing 210098China College of Renewable Energy Hohai UniversityNanjing 210098China

Coastal wetlands are hotspots for nitrogen(N)cycling,and crab burrowing is known to transform N in intertidal marsh ***,the underlying mechanisms remain *** study conducted field experiments and used indoor control test devices to investigate the seasonal response of nitrogen to crab disturbance at the sediment-water interface in coastal tidal flat *** results showed that crab disturbance exhibited significant seasonality with large seasonal differences in cave density and *** to crab disturbance,nitrogen fuxes at the sediment-water interface were much greater in the box with crabs than in the box without *** summer,NH-N showed a positive flux from the sediment to the overlying water,but NO2-N and NOg-N showed positive fluxes from the sediment to the overlying water only in early *** winter,NH-N showed a positive flux from the sediment to the overlying water,but NO-N and NO,-N both exhibited positive and negative *** results indicated that the presence of crab burrows can cause the aerobic layer to move downward by approximately 8-15 cm in summer and directly promote nitrification at the sediment surface.

关键词： Coastal tidal flat wetland Crab disturbance Nitrogen flux Nitrification Denitrification Sediment-water interface

Functional assessment of cadherin as a shared mechanism for cross/dual resistance to Cry1Ac and Cry2Ab in Helicoverpa zea

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Journal of Integrative Agriculture 2024年第5期23卷 1604-1617页

作者： Jizhen wei Min Zhang pin li Zhongyuan Deng Xinming Yin Shiheng An Xianchun li State Key Laboratory of Wheat and Maize Crop Science/College of Plant Protection Henan Agricultural UniversityZhengzhou 450046China Department of Entomology and BIO5 Institute University of ArizonaTucsonAZ 85721USA School of Agricultural Sciences Zhengzhou UniversityZhengzhou 450001China

Helicoverpa zea is a major target pest of pyramided transgenic crops expressing Cry1,Cry2 and/or Vip3Aa proteins from Bacillus thuringiensis(Bt)in the United ***-selected Cry1Ac/Cry2Ab cross resistance and fieldevolved practical dual resistance of *** to these two toxins have been widely *** the widespread Cry1Ac/Cy2Ab dual resistance of *** has resulted from the selection of one shared or two independent resistance mechanisms by pyramided Bt crops remains *** is a well-confirmed receptor of Cry1Ac and a suggested receptor of Cry2Ab in at least three Lepidopteran *** test whether cadherin may serve as one shared mechanism for the cross and dual resistance of *** to Cry1Ac and Cry2Ab,we cloned *** cadherin(HzCadherin)cDNA and studied its functional roles in the mode of action of Cry1Ac and Cry2Ab by gain-and lossof-function *** expression of HzCadherin in *** midgut,*** fat body and Sf9 cells made all three of these cell lines more susceptible to activated Cry1Ac but not activated Cry2Ab,whereas silencing HzCadherin of *** midgut and fat body cells significantly reduced the susceptibility to Cry1Ac but not ***,suppressing HzCadherin with siRNA made *** larvae resistant to *** results clearly demonstrate that HzCadherin is not a receptor for Cry2Ab,and thus it is unlikely to serve as one shared mechanism for the cross and dual resistance of *** to Cry1Ac and Cry2Ab.

关键词： Bt crops cadherin Cry toxin receptor resistance mechanism

Fast source mask co-optimization method for high-NA EUV lithography

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Opto-Electronic Advances 2024年第4期7卷 44-54页

作者： Ziqi li lisong dong Xu Ma Yayi wei Eda Center Institute of Microelectronics of Chinese Academy of SciencesBeijing 100029China Key Laboratory of Photoelectronic Imaging Technology and System of Ministry of Education of China School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China Guangdong Greater Bay Area Applied Research Institute of Integrated Circuit and Systems Guangzhou 510700China

Extreme ultraviolet(EUV)lithography with high numerical aperture(NA)is a future technology to manufacture the integrated circuit in sub-nanometer ***,source mask co-optimization(SMO)is an extensively used approach for advanced lithography process beyond 28 nm technology *** work proposes a novel SMO method to improve the image fidelity of high-NA EUV lithography system.A fast high-NA EUV lithography imaging model is established first,which includes the effects of mask three-dimensional structure and anamorphic ***,this paper develops an efficient SMO method that combines the gradient-based mask optimization algorithm and the compressivesensing-based source optimization algorithm.A mask rule check(MRC)process is further proposed to simplify the optimized mask *** illustrate that the proposed SMO method can significantly reduce the lithography patterning error,and maintain high computational efficiency.

关键词： computational lithography high-NA EUV lithography source-mask co-optimization lithography imaging model

High-performance sodium storage for cobalt phosphide composite array electrodes

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Rare Metals 2024年第8期43卷 3724-3734页

作者： Man Zhang Xiao-Xu liu Tian-Yi Ji Yang li da-wei Sheng Shao-dong li Pei-Pei Ren Ze-Xiang Shen School of Material Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore

Transition metal phosphides hold great potential as sodium-ion batteries anode materials owing to their high theoretical capacity and modest ***,volume changes and low intrinsic conductivity seriously largely hinder the further development of metal phosphide *** design of phosphide anode materials with reasonable structure is conducive to solving the problems of volume expansion and slow reaction kinetics during the *** this work,a composite material integrating zeolite imidazolate backbone(ZIF) and carbon materials was synthesized by the original growth ***,by the oxidation-phosphating process,CoP nanoarray composites riveted to carbon fiber(CoP@CF) were *** the CoP@CF,CoP nanoparticles are uniformly distributed on ZIF-derived carbon,reducing agglomeration and volume change during *** also provides a highly conductive network for the active material,improving the electrode ***,when evaluated as an anode for sodium-ion batteries,CoP@CF electrode displays enhanced reversible capacity(262 mAh·g^(-1) at 0.1 A·g^(-1)after 100 cycles),which is much better than that of pure CF electrode(57 mAh·g^(-1) at 0.1 A·g^(-1) after 100 cycles)prepared without the addition of *** rate performance of CoP@CF electrode is also superior to that of pure CF electrode at various current densities from 0.05 to1 A·g^(-1).The sodium storage behavior of CoP@CF was revealed by ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,and synchrotron radiation absorption *** method provides a reference for the design and synthesis of anode materials in sodium-ion batteries.

关键词： Cobalt phosphide Array structure Freestanding anodes Sodium-ion batteries

The prognostic value of collateral circulation in coronary chronic total occlusion underwent percutaneous coronary intervention

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Journal of Geriatric Cardiology 2024年第2期21卷 232-241页

作者： Xiao-Ying HU wei-Xian YANG Chang-dong GUAN li-Hua xie Ke-Fei DOU Yong-Jian WU jin-Qing YUAN Jie QIAN Yue-jin YANG Shu-Bin QIAO Lei SONG Department of Cardiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina National Clinical Research Center for Cardiovascular Diseases BeijingChina Catheterization Laboratories Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

BACKGROUND The prognostic value of coronary collateral circulation(CC)in patients undergoing chronic total occlusion(CTO)percutaneous coronary intervention(PCI)is *** purpose of the study was to assess the prognostic value of current two CC grading systems and their association with long-term outcomes in patients with CTO underwent *** We consecutively enrolled patients with single-vessel CTO underwent PCI between January 2010 and *** patients were categorized into well-developed or poor-developed collaterals group according to angiographic Werner's CC(grade 2 *** 0–1)or Rentrop(grade 3 *** 0–2)grading *** primary endpoint was 5-year cardiac *** Of 2452 enrolled patients,the overall technical success rate was 74.1%.Well-developed collaterals were present in686 patients(28.0%)defined by Werner's CC grade 2,and in 1145 patients(46.7%)by Rentrop grade *** to Werner's CC grading system,patients with well-developed collaterals had a lower rate of 5-year cardiac death compared with those with poordeveloped collaterals(1.6%vs.3.3%,P=0.02),those with suboptimal recanalization was associated with higher rate of 5-year cardiac death compared with optimal recanalization(4.7%vs.0.8%,P=0.01)and failure patients(4.7%vs.1.6%,P=0.12).However,the similar effect was not shown in Rentrop grading *** In patients with the single-vessel CTO underwent PCI,well-developed collaterals by Werner's CC definition were associated with lower rate of 5-year cardiac ***'s CC grading system had a greater prognostic value than Rentrop grading system in patients with CTO underwent PCI.

关键词： coronary collateral occlusion

Considering individual game behavior and time delay in the multi-channel rumor propagation model

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Communications in Theoretical Physics 2024年第7期76卷 9-29页

作者： Yafang dong liang'an Huo Xiaoxiao xie Ming li Business School University of Shanghai for Science and TechnologyShanghai 200093China School of Intelligent Emergency Management University of Shanghai for Science and TechnologyShanghai 200093China

The rapid development of the Internet has accelerated the spread of rumors,posing challenges to social cohesion and *** address this,a multi-channel rumor propagation model incorporating individual game behavior and time delay is *** depicts individuals strategically choosing propagation channels in the rumor spread process,capturing real-world intricacies more ***,the model allowing spreaders to choose between text and video information base *** adoption hinges on benefits versus costs,with payoffs dictating strategy and the propagation process determining an individual's *** theoretical analysis of the model,the propagation threshold and equilibrium points are *** the stability of the model is further demonstrated based on Routh-Hurwitz judgment and Descartes'Rule of *** simulations are conducted to verify the correctness of the theoretical results and the sensitivity of the model to key *** outcomes reveal that increasing the propagation cost of spreaders can significantly curb the spread of *** contrast to the classical ISR model,rumors spread faster and more widely in the improved multi-channel rumor propagation model in this paper,which is a feature more aligned with real-world ***,the validity and predictive ability of the model are verified by using real rumor propagation data sets,indicating that the improved multi-channel rumor propagation model has good practical application and predictive value.

关键词： multi-channel rumor propagation time delay game behavior