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汉日对比视角下非致使“在LVO”的语义及分化

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外语导刊 2024年第4期47卷 73-81,140,159,160页

作者：杨晓敏冯予力复旦大学外国语言文学学院上海200433

提示处所的介词“在”的句中位置、语义用法备受关注,但描写尚不完整。本文在汉日对比视角下,通过意象图式来表征非致使“在LVO”的语义分类,结合语义指向和动词特征的分析,发现非致使“在LVO”可对应日语格助词「で(提示事件发生处所)... 详细信息

提示处所的介词“在”的句中位置、语义用法备受关注,但描写尚不完整。本文在汉日对比视角下,通过意象图式来表征非致使“在LVO”的语义分类,结合语义指向和动词特征的分析,发现非致使“在LVO”可对应日语格助词「で(提示事件发生处所)」「で(提示工具)」「から(提示起点)」「に(提示物体静态位置)」,证实了非致使“在LVO”的语义存在分化,该分化呈现出由动态到静态、由行为到结果的连续性特征。

关键词：在LVO 汉日对比意象图式语义指向语义分化

Safe semi-supervised learning: a brief introduction

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Frontiers of Computer Science 2019年第4期13卷 669-676页

作者： yu-feng li De-Ming liANG National Key Laboratory for Novel Software Technology Nanjing University Nanjing 210023 China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210023 China

Semi-supervised learning constructs the predictive model by learning from a few labeled training examples and a large pool of unlabeled ones. It has a wide range of application scenarios and has attracted much attention in the past decades. However, it is noteworthy that although the learning performance is expected to be improved by exploiting unlabeled data, some empirical studies show that there are situations where the use of unlabeled data may degenerate the performance. Thus, it is advisable to be able to exploit unlabeled data safely. This article reviews some research progress of safe semi-supervised learning, focusing on three types of safeness issue: data quality, where the training data is risky or of low?quality;model uncertainty, where the learning algorithm fails to handle the uncertainty during training;measure diversity, where the safe performance could be adapted to diverse measures.

关键词： machine learning semi-supervised learning safe

EFFECT OF INSTABIliTIES OF FLOW ON MESOSCALE PREDICTABIliTY OF WEATHER SYSTEMS

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Journal of Hydrodynamics 2011年第2期23卷 193-203页

作者： LUO yu ZHANG li-feng Institute of Meteorology PLA University of Science and Technology Nanjing 211101

The numerical solution of Boussinesq equations is worked out as an initial-value problem to study the effect of the instabilities of flow on the initial error growth and mesoscale predictability. The development of weather systems depends on different dynamic instability mechanisms according to the spatial scales of the system and the development of mesoscale systems is determined by symmetric instability. Since symmetric instability dominates among the three types of dynamic instability, it makes the prediction of the associated mesoscale systems more sensitive to initial uncertainties. This indicates that the stronger instability leads to faster initial error growth and thus limits the mesoscale predictability. Besides dynamic instability, the impact of thermodynamic instability is also explored. The evolvement of convective instability manifests as dramatic variation in small spatial scale and short temporal scale, and furthermore, it exhibits the upscale growth. Since these features determine the initial error growth, the mesoscale systems arising from convective instability are less predictable and the upscale error growth limits the predictability of larger scales. The latent heating is responsible for changing the stability of flow and subsequently influencing the error growth and the predictability.

关键词： instabilities of flow mesoscale system predictability initial errors

Instance selection method for improving graph-based semi-supervised learning

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Frontiers of Computer Science 2018年第4期12卷 725-735页

作者： Hai WANG Shao-Bo WANG yu-feng li 1 National Key Laboratory for Novel Software Technology Nanjing University Nanjing 210023 China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210023 China

Graph-based semi-supervised learning is an important semi-supervised learning paradigm. Although graphbased semi-supervised learning methods have been shown to be helpful in various situations, they may adversely affect performance when using unlabeled data. In this paper, we propose a new graph-based semi-supervised learning method based on instance selection in order to reduce the chances of performance degeneration. Our basic idea is that given a set of unlabeled instances, it is not the best approach to exploit all the unlabeled instances; instead, we should exploit the unlabeled instances that are highly likely to help improve the performance, while not taking into account the ones with high risk. We develop both transductive and inductive variants of our method. Experiments on a broad range of data sets show that the chances of performance degeneration of our proposed method are much smaller than those of many state-of-the-art graph-based semi-supervised learning methods.

关键词： graph-based semi-supervised learning performance degeneration instance selection

Modeling Method for Flexible Energy Behaviors in CNC Machining Systems

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 156-166页

作者： yu-feng li yu-lin Wang Yan He Yan Wang Shen-Long lin Economics and Business Administration Chongqing University State Key Laboratory of Mechanical Transmission Chongqing University School of Mechanical Engineering Nanjing University of Science and Technology Department of Computing Mathematics and Engineering University of Brighton

CNC machining systems are inevitably confronted with frequent changes in energy behaviors because they are widely used to perform various machining tasks. It is a challenge to understand and analyze the flexible energy behaviors in CNC machining systems. A method to model flexible energy behaviors in CNC machining systems based on hierarchical objected-oriented Petri net(HOONet) is proposed. The structure of the HOONet is constructed of a high-level model and detail models. The former is used to model operational states for CNC machining systems, and the latter is used to analyze the component models for operational states. The machining parameters having great impacts on energy behaviors in CNC machining systems are declared with the data dictionary in HOONet models. A case study based on a CNC lathe is presented to demonstrate the proposed modeling method. The results show that it is effective for modeling flexible energy behaviors and providing a fine-grained description to quantitatively analyze the energy consumption of CNC machining systems.

关键词： Energy behaviors CNC machining systems Modeling method HOONet

Synthesis and characterization of a novel series of pyrimidinylthiaalkoxycalix[4]arenes

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Chinese Chemical Letters 2007年第4期18卷 403-406页

作者： Bing Zhao Ya Qing feng yu Kun li School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

A novel series of pyrimidinylthiaalkoxycalix[4]arenes with the reaction between 4,6-dimethylpyrimidine-2-thiol and the different dibromides calix[4]aryl groups have been synthesized and structurally characterized by IR, 1H NMR and MS. From their analysis data, it was found that compounds 8, 9, 11 adopted a cone conformation, while compound 10 existed as a mixture of conformations.

关键词： Pyrimidinylthiaalkoxycalixarenes Synthesis Characterization Conformation

Pd cluster decorated free standing flexible cathode for high performance li-oxygen batteries

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Nano Research 2024年第4期17卷 2678-2686页

作者： liang Guo Guoliang Zhang Ruonan Yang Dongmei Zhang Xiuqi Zhang Han yu Xia li feng Dang Key Laboratory for liquid-Solid Structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

As a promising candidate for the next generation energy storage system,rechargeable lithium-oxygen batteries(LOBs)still face substantial challenges caused by insulating discharge products that preclude their practical *** highly efficient cathode catalysts capable of facilitating formation/decomposition of discharge products is considered as an essential approach towards high performance ***,Pd decorated Te nanowires(Pd@Te NWs)were synthesized as advanced catalyst in LOBs to maximize Pd utilization and achieve synergistic effect,in which Pd clusters were uniformly grown on Te substrate though regulating the Pd:Te ***,Pd@Te nanowires assembled into an interpenetrating network-like structure by vacuum filtration and employed as flexible cathode,enabling LOBs achieved an ultralong 190 cycles stability and a superior specific capacity of 3.35 mAh·cm^(-2).Experimental studies and density functional theory(DFT)calculations reveal the excellent catalytic ability of Pd@Te and synergistic catalytic mechanism of Pd and Te,in which uniform electron distribution,extensive electron exchange,and large adsorption distance between Pd cluster and discharge products promote homogeneous adsorption/desorption of discharge products,while the high adsorption energy of Te substrate for li species reduces the initial dynamical energy barrier during discharging *** current work provides viable strategy to design composite catalysts for flexible cathode of LOBs with synergistic catalytic effects.

关键词： flexible lithium-oxygen batteries Pd@Te synergistic catalysis cathode catalysts density functional theory(DFT)calculation

Augmented Flow Simulation Based on Tight Coupling Between Video Reconstruction and Eulerian Models

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Journal of Computer Science & Technology 2018年第3期33卷 452-462页

作者： feng-yu li Chang-Bo Wang Hong Qin Hong-Yan Quan School of Computer Science and Software Engineering East China Normal University Shanghai 200062 China Department of Computer Science State University of New York at Stony Brook NY 11794-4400 U.S.A

Hybrid approaches such as combining video data with pure physics-based simulation have been popular in the recent decade for computer graphics. The key motivation is to clearly retain salient advantages from both data-driven method and model-centric numerical simulation, while overcoming certain difficulties of both. The Eulerian method, which has been widely employed in flow simulation, stores variables such as velocity and density on regular Cartesian grids, thereby it could be associated with （volumetric） video data on the same domain. This paper proposes a novel method for flow simulation, which is tightly coupling video-based reconstruction with physically-based simulation and making use of meaningful physical attributes during re-simulation. First, we reconstruct the density field from a single-view video. Second, we estimate the velocity field using the reconstructed density field as prior. In the iterative process, the pressure projection can be treated as a physical constraint and the results of each step are corrected by obtained velocity field in the Eulerian framework. Third, we use the reconstructed density field and velocity field to guide the Eulerian simulation with anticipated new results. Through the guidance of video data, we can produce new flows that closely match with the real scene exhibited in data acquisition. Moreover, in the multigrid Eulerian simulation, we can generate new visual effects which cannot be created from raw video acquisition, with a goal of easily producing many more visually interesting results and respecting true physical attributes at the same time. We demonstrate salient advantages of our hybrid method with a variety of animation examples.

关键词： video reconstruction velocity estimation fluid simulation volume modeling and re-simulation

Mechanical property of artificial methane hydrate under triaxial compression

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Journal of Natural Gas Chemistry 2010年第3期19卷 246-250页

作者： Yongchen Song feng yu Yanghui li Weiguo liu Jiafei Zhao Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of Technology Dalian 116024 Liaoning China

Methane production from hydrate reservoir may induce seabed slide and deformation of the hydrate-bearing *** research on mechanical properties of methane hydrate is considered to be important for developing an efficient methane exploitation *** this paper,a triaxial test system containing a pressure crystal device was developed with the conditions to stabilize the hydrate.A series of triaxial shear tests were carried out on artificial methane hydrate *** addition,mechanical characteristics of methane hydrate were studied with the strain rates of 0.1 and 1.0 mm/min,respectively,under the conditions of different temperatures（T =-5,-10,and-20 ℃） and confining pressures（P = 0,5,10,15,and 20 MPa）.The preliminary results show that when the confining pressure was less than 10 MPa,the increase of confining pressure leaded to the enhancement of shear ***,the decreasing temperature and the increasing strain rate both caused the increase in shear strength.

关键词： triaxial mechanical properties confining pressure temperature strain rate