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LTL Formulae to Bchi Automata Translation Using on-the-Fly De-generalization

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Chinese Journal of Electronics 2015年第4期24卷 674-678页

作者： shan Laixiang QIN Zheng Department of Computer Science and Technology Tsinghua University School of Software Tsinghua University

In this paper, we present a conversion algorithm to translate a Linear temporal logic(LTL) formula to a Bu¨chi automaton(BA) directly. Acceptance degree(AD) is presented to record acceptance conditions satisfied in each state and transition of the BA. According to AD, on-the-fly de-generalization algorithm, which is different from the standard de-generalization algorithm, is conceived and implemented. On-the-fly de-generalization algorithm is performed in the case of the given LTL formula containing U-subformulae or F-subformulae, that is,it is performed as required during the expansion of the given LTL formula. We compare the conversion algorithm presented in this paper to previous works, and show that it is more efficient for a series of LTL formulae in common use.

关键词： Formal method Model checking Linear temporal logic On-the-fly de-generalization

Influence of Pre-strain on the Mechanical Properties of A6111-T4P Sheet with Bake Hardening

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 678-683页

作者： shan-shan Li Jie-Shi Chen Jun Chen Cedric Xia Danielle Zeng Institute of Forming Technology and Equipment School of Materials Science and Engineering Shanghai Jiao Tong University Research and Innovation Center Ford Motor Company

A6111 is an aluminum alloy, which exhibits good formability and excellent bake hardening property. This study aimed to reveal the influence of strain path, pre-strain orientation （c0 as well as pre-strain level on the mechanical properties of A6111-T4P sheet under bake treatment through uniaxial tension test. （0-5）% pre-strain, 150-170 ℃ bake temperature and 20-30 min bake time were considered in the study by referring to the actual production process. The results show that both pre-strain level and strain path play significant roles in improving the material properties. In the condition that tensile orientation （β） parallel with pre-strain orientation （β= a）, the yield strength can be remarkably improved, and much higher parameter of n in Hockett-Sherby model can be obtained than those when tensile orientation non-parallel with pre-strain orientation （a≠ β）. In addition, when the pre-strain level, paint bake process were settled and β = a, the curves obtained in five tension orientations are similar in the plastic deformation stage.

关键词： Aluminum alloy Pre-strain Bake hardening Mechanical properties

Herbivore and native plant diversity synergistically resist alien plant invasion regardless of nutrient conditions

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Plant Diversity 2024年第5期46卷 640-647页

作者： Liping shan Meng Hou Key Laboratory of Wetland Ecology and Environment State Key Laboratory of Black Soils Conservation and UtilizationNortheast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China

Alien plant invasion success can be inhibited by two key biotic factors:native herbivores and plant ***,few studies have experimentally tested whether these factors interact to synergistically resist invasion success,especially factoring in changing global environments(*** enrichment).Here we tested how the synergy between native herbivores and plant diversity affects alien plant invasion success in various nutrient *** this purpose,we exposed alien plant species in potmesocosms to different levels of native plant diversity(4 vs.8 species),native generalist herbivores,and high and low soil nutrient *** found that generalist herbivores preferred alien plants to native plants,inhibiting invasion success in a native *** inhibition was amplified by highly diverse native ***,the amplified effect between herbivory and native plant diversity was independent of nutrient *** results suggest that a higher diversity of native communities can strengthen the resistance of native generalist herbivores to alien plant invasions by enhancing herbivory *** synergistic effect remains in force in nutrient-enriched habitats that are always invaded by alien plant *** results shed light on the effective control of plant invasions using multi-trophic means,even in the face of future global changes.

关键词： Biological invasion Biotic resistance Diversity conservation Plant-herbivore interactions Resource availability Global change

Voter model in a random environment in Zd

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Frontiers of Mathematics in China 2012年第5期7卷 895-905页

作者： Zhichao shan Dayue CHEN School of Mathematical Sciences Peking University Beijing 100871 China Center for Statistical Science Peking University Beijing 100871 China

We consider the voter model with flip rates determined by {ue, e ∈ Ed}, where Ed is the set of all non-oriented nearest-neighbour edges in the Euclidean lattice Zd. Suppose that {ue, e ∈ Ed} are independent and identically distributed （i.i.d.） random variables satisfying ue ≥ 1. We prove that when d = 2, almost surely for all random environments, the voter model has only two extremal invariant measures： δ0 and δ1.

关键词： Voter model random walk random environment duality

Effects of temperature on UV-B-induced DNA damage and photorepair in Arabidopsis thaliana

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Journal of Environmental Sciences 2004年第1期16卷 173-176页

作者： LIShao-shan WANGYan BJOERNLarsOlof SchoolofLifeSciences SouthChinaNormalUniversityGuangzhou510631China SchoolofLifeSciencesandTechnology JinanUniversityGuangzhou510632China DepartmentofPlantPhysiology LundUniversityBox117SE-22100LundSweden

DNA damage in the form of cyclobutane pyrimidine dimers(CPDs) and (6-4) photoproducts(6-4PPs) induced by UV-B radiation in Arabidopsis thaliana at different temperatures was investigated using ELISA with specific monoclonal antibodies. CPDs and 6-4PPs increased during 3 h UV-B exposure, but further exposure led to decreases. Contrary to the commonly accepted view that DNA damage induced by UV-B radiation is temperature-independent because of its photochemical nature, we found UV-B-induction of CPDs and 6-4PPs in Arabidopsis to be slower at a low than at a high temperature. Photorepair of CPDs at 24℃ was much faster than that at 0℃ and 12℃, with 50% CPDs removal during 1 h exposure to white light. Photorepair of 6-4PPs at 12℃ was very slow as compared with that at 24℃, and almost no removal of 6-4PPs was detected after 4 h exposure to white light at 0℃. There was evidence to suggest that temperature-dependent DNA damage and photorepair could have important ecological implications.

关键词： Arabidopsis thaliana cyclobutane pyrimidine dimers(CPDs) DNA repair (6-4) photoproducts(6-4PPs) temperature UV-B radiation

A Scoping Review of Global Guidelines for the Disclosure of Secondary Genomic Findings to Inform the Establishment of Guidelines in China

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China CDC weekly 2022年第32期4卷 697-705页

作者： shan Jiang School of Population and Public Health the University of British ColumbiaVancouverBCCanada

The detection and disclosure of secondary findings(SFs)is a preventive strategy for medically-actionable hereditary health *** countries have guidelines on management and disclosure of SFs,while others avoid detection and disclosure of *** study is a review of clinical guidelines from six countries and the European Union to identify similarities and differences among SF *** from this review supports harmonization of guidelines across countries to promote broad international collaborations on genomics and to benefit precision *** study can serve as a reference for development of SF management guidelines in China by contributing evidence from other countries to the ethical and methodological challenges under debate.

关键词： finding hereditary Secondary

Earth Pressure Distribution and Sand Deformation Around Modified Suction Caissons(MSCs) Under Monotonic Lateral Loading

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China Ocean Engineering 2019年第2期33卷 198-206页

作者： LI Da-yong LI shan-shan ZHANG Yu-kun CHEN Fu-quan College of Civil Engineering Fuzhou University Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science and Technology

The modified suction caisson(MSC) is a novel type of foundation for ocean engineering, consisting of a short external closed-top cylinder-shaped structure surrounding the upper part of the regular suction caisson(RSC). The MSC can provide larger lateral bearing capacity and limit the deflection compared with the RSC. Therefore, the MSC can be much more appropriate to use as an offshore wind turbine foundation. Model tests on the MSC in saturated sand subjected to monotonic lateral loading were carried out to investigate the effects of external structure sizes on the sand surface deformation and the earth pressure distribution along the embedded depth. Test results show that the deformation range of the sand surface increases with the increasing width and length of the external structure. The magnitude of sand upheaval around the MSC is smaller than that of the RSC and the sand upheaval value around the MSC in the loading direction decreases with the increasing external structure dimensions. The net earth pressure in the loading direction acting on the internal compartment of the MSC is smaller than that of the RSC at the same embedded depth. The maximum net earth pressure acting on the external structure outer wall in the loading direction is larger than that of the internal compartment, indicating that a considerable amount of the lateral load and moment is resisted by the external skirt structure.

关键词： MSC (modified suction caisson) RSC (regular suction caisson) model tests monotonic lateral loading deformation of sand surface earth pressure distribution

Computations of unsteady transonic flow over airfoil at low Reynolds number

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航空动力学报 2013年第3期28卷 646-658页

作者： ZHU Hai-tao shan Peng School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

Transonic flow over a thin airfoil at low Reynolds number was studied numerically by directly solving two-dimensional full Navier-Stokes equations through 5th order weighted essentially non-oscillatory(WENO) scheme without using any turbulence model.A series of distinguished unsteady phenomena for a thin 2-D transonic airfoil flow were *** to continuous adverse pressure gradient in the subsonic flow downstream of the sonic line,the unsteady separated boundary layer with main vortex and secondary vortex was developed at the rear of the *** the trailing edge,the vortex-shedding was characterized by periodical connection of the main vortex and secondary vortex on the other side of the *** unsteady separation and vortex-shedding occurred with the same *** the airfoil surface,the average pulse pressure related to the unsteady supersonic region was obviously smaller than that related to the vortex-shedding at the trailing *** the attack angle increasing from 0°to 2°,the frequency of vortex-shedding decreases about 4.2%.At last,the turbulence intensity and many second-order statistics in the wake region were investigated.

关键词： transonic flow unsteady flow direct numerical simulation(DNS) unsteady separation airfoil vortex-shedding

Perovskite Single Crystals: Synthesis, Properties, and Applications

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Journal of Electronic Science and Technology 2021年第2期19卷 119-143页

作者： shan-shan Rong M.Bilal Faheem Yan-Bo Li Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054

Perovskite single crystals have gained enormous attention in recent years due to their facile synthesis and excellent optoelectronic properties including the long carrier diffusion length,high carrier mobility,low trap density,and tunable absorption edge ranging from ultra-violet(UV)to near-infrared(NIR),which offer potential for applications in solar cells,photodetectors(PDs),lasers,*** this review,we summarized the synthesis,properties,and applications of organic-inorganic mixed and all-inorganic perovskite single crystals,particularly those through the solution synthesis *** towards the crystal growth and stability with future perspectives were also briefly described at the end of this paper.

关键词： Laser perovskite photodetector(PD) single crystal solar cell