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Journal of Forestry Research 2023年第3期34卷 841-852页

作者： yao xu Zhiguang Zhang College of Economics and Management Nanjing Forestry UniversityNanjing 210037People’s Republic of China System Engineering Institute for Environment and Development Nanjing Forestry UniversityNanjing 210037People’s Republic of China

As a cultural concept refl ecting the relationship between humans and forests,forest culture plays an active role in sustainable forest *** parks provide a wide range of ecosystem services essential for the sustainable development of society,and the relationships between forest culture,green construction and management of forest parks have practical signifi *** study aimed to understand the interaction and process of forest culture infl uencing green construction and management in forest parks with the models Knowledge-Attitude-Practice(KAP)and Theory of Planned Behavior(TPB)by proposing a theoretical *** hypotheses were tested using data collected from 193 forest park employees in Heilongjiang Province,*** results show that forest culture had a signifi cant infl uence on green construction and forest *** addition,subjective norm and perceived behavioral control directly impacted behavior in green construction and management of the forest park,whereas attitude did not have an *** norm had a direct eff ect on *** between constructs show that forest culture had an indirect eff ect on planning and construction,and on ecological and economic ***,it supported three of four hypotheses within the proposed model in determining the infl uence of forest culture on green construction and management.

关键词： Forest parks Forest culture Green construction and management Knowledge-attitudepractice Theory of planned behavior

Wind-wave hindcast in the Yellow Sea and the Bohai Sea from the year 1988 to 2002

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Acta Oceanologica Sinica 2016年第3期35卷 46-53页

作者： HE Hailun xu yao State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic AdministrationHangzhou 310012China Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

We performed long-term wind-wave hindcast in the Yellow Sea and the Bohai Sea from the year 1988 to 2002, and then analyzed the regional wave climate. Comparisons between model results and satellite data are generally consistent on monthly mean significant wave height. Then we discuss the temporal and spatial characteristics of the climatological monthly mean significant wave heights and mean wave periods. The climatologically spatial patterns are observed as increasing from northwest to southeast and from offshore to deep-water area for both significant wave height and mean wave period, and the patterns are highly related to the wind forcing and local topography. Seasonal variations of wave parameters are also significant. Furthermore, we compute the extreme values of wind and significant wave height using statistical methods. Results reveal the spatial patterns of N-year return significant wave height in the Yellow Sea and the Bohai Sea, and we discuss the relationship between extreme values of significant wave height and wind forcing.

关键词： wave climate extreme value analysis the Yellow Sea wave hindcast WAVEWATCH-Ⅲ

Research of Step-down Stress Accelerated Degradation Data Assessment Method of a Certain Type of Missile Tank

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Chinese Journal of Aeronautics 2012年第6期25卷 917-924页

作者： yao Jun xu Mingge ZHONG Weiqiang School of Reliability and System Engineering Beihang University Beijing 100191 China

The performance degradation rates of the missile tank are generally time-varying functions uneasily evaluated by general classical evaluation methods. This paper develops a segmented nonlinear accelerated degradation model （SNADM） based on the equivalent method of accumulative damage theory, which tackles the problem that product life is difficult to be determined with degradation rate being a function of the variable of time. A segmented expression of the function of population accumulative degradation is derived. And combined with nonlinear function, an accelerated degradation function, i.e., SNADM is obtained. The parameters of the SNADM are identified by numerical iteration, and the statistical function of degradation track is extrapolated. The reliability function is determined through the type of random process of the degradation distribution. Then an evaluation of product storage life is undertaken by combining the statistical function of degradation track, reliability function and threshold. An example of a missile tank undergoes a step-down stress accelerated degradation test （SDSADT）, in which the results with the SNADM and the classical method are evaluated and compared. The technology introduced is validated with the resultant coincidence of both evaluated and field storage lives.

关键词： reliability accelerated degradation model step-down stress testing life assessment cumulative damage

Prompt optical emission from gamma-ray bursts with multiple timescale variability of central engine activities

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Research in Astronomy and Astrophysics 2014年第4期14卷 411-422页

作者： Si-yao xu Zhuo Li Department of Astronomy and Kavli Institute for Astronomy and Astrophysics Peking University Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences

Complete high-resolution light curves of GRB 080319B observed by Swift present an opportunity for detailed temporal analysis of prompt optical emission. With a two-component distribution of initial Lorentz factors, we simulate the dynamical process of shells being ejected from the central engine in the framework of the in- ternal shock model. The emitted radiations are decomposed into different frequency ranges for a temporal correlation analysis between the light curves in different energy bands. The resulting prompt optical and gamma-ray emissions show similar tempo- ral profiles, with both showing a superposition of a component with slow variability and a component with fast variability, except that the gamma-ray light curve is much more variable than its optical counterpart. The variability in the simulated light curves and the strong correlation with a time lag between the optical and gamma-ray emis- sions are in good agreement with observations of GRB 080319B. Our simulations suggest that the variations seen in the light curves stem from the temporal structure of the shells injected from the central engine of gamma-ray bursts. Future observations with high temporal resolution of prompt optical emission from GRBs, e.g., by UFFO- Pathfinder and SVOM-GWAC, will provide a useful tool for investigating the central engine activity.

关键词： gamma rays: bursts- GRB 080319B

Normality of Tetravalent Cayley Graphs of Odd Prime-cube Order and Its Application

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Acta Mathematica Sinica,English Series 2005年第4期21卷 903-912页

作者： Yan Quan FENG Ming yao xu Department of Mathematics Beijing Jiaotong University Beijing 100044 P. R. China LMAM Institute of Mathematics Peking University Beijing 100871 P. R. China

Let p be an odd prime. In this paper we prove that all tetravalent connected Cayley graphs of order p^3 are normal. As an application, a classification of tetravalent symmetric graphs of odd prime-cube order is given.

关键词： Cayley graph Normal Cayley graph Symmetric graph

Preparation and properties of magnetic iron oxide nanotubes

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Particuology 2008年第5期6卷 334-339页

作者： Baoliang Lv yao xu Dong Wu Yuhan Sun State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 China Graduate University of the Chinese Academy of Sciences Beijing 100039 China

Magnetite （Fe3O4） nanotubes were prepared by reducing synthesized hematite （α-Fe2O3） nanotubes in 5%H2＋95% Ar atmosphere, and then maghemite （γ-Fe2O3） nanotubes were obtained by re-oxidizing the Fe3O4 nanotubes. The nanotube structure was kept from collapsing or sintering throughout the high temperature reducing and re-oxidizing processes. The coercivities of the Fe304 and γ-Fe2O3 nanotubes synthesized were found to be 340.22 Oe and 342.23 Oe, respectively, both higher than other nanostructures with the same phase and of similar size. Both adsorbed phosphate and the nanotube structure are considered responsible for this high coercivity.

关键词： Nanostructures Iron oxides Nanotubes Magnetic properties

Non-surfactant synthesis of mesoporous silica with dye as template

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Chinese Chemical Letters 2007年第10期18卷 1182-1186页

作者： Peng Feng yao xu Dong Wu State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

A novel non-surfactant method was described to synthesize mesoporous silica using dye basic fuchsin as template. Chemical reactions were introduced into the formation of mesopores rather than the weak electrostatic or hydrogen-bonding interactions in the traditional surfactant routes. The reactant composition was found to be crucial to the pore structure of objective product. The formation mechanism of mesopore was also proved.

关键词： Mesoporous materials Non-surfactant routine Dye

Preparation of α-Fe_2O_3 Nanodisks by Blocking the Growth of (001) Plane

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Journal of Materials Science & Technology 2009年第2期25卷 155-158页

Based on the difference of hydroxy group configuration on the special adsorption and coordination of phosphate on the dispersed α-Fe2O3 nanodisks with diameter of 150-200 nm different planes of α-Fe2O3 nanoparticles, using （001） plane of α-Fe2O3, well-crystallized and well and thickness of 40-80 nm were synthesized via a hydrotherrnal method. The magnetic properties of synthesized nanodisks were investigated. It was found that the nanodisks possessed a saturation magnetization （Ms） of 0.38 emu/g, a rernanent magnetization （Mr） of 0.031 ernu/g and a coercivity of 452.91 Oe at room temperature. The Mr and coercivity of synthesized α-Fe2O3 nanodisks are higher and the Ms is lower than those of other previously reported α-Fe2O3 nanostructures.

关键词： Nanomaterials α-Fe2O3 Nanodisk Magnetic materials

Unified Classification and Rejection:A One-versus-all Framework

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Machine Intelligence Research 2024年第5期21卷 870-887页

作者： Zhen Cheng xu-yao Zhang Cheng-Lin Liu State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing100049China

Classifying patterns of known classes and rejecting ambiguous and novel(also called as out-of-distribution(OOD))inputs are involved in open world pattern *** neural network models usually excel in closed-set classification while perform poorly in rejecting OOD *** tackle this problem,numerous methods have been designed to perform open set recognition(OSR)or OOD rejection/detection *** methods mostly take post-training score transformation or hybrid models to ensure low scores on OOD inputs while separating known *** this paper,we attempt to build a unified framework for building open set classifiers for both classification and OOD *** formulate the open set recognition of K-known-class as a(K+1)-class classification problem with model trained on known-class samples *** decomposing the K-class problem into K one-versus-all(OVA)binary classification tasks and binding some parameters,we show that combining the scores of OVA classifiers can give(K+1)-class posterior probabilities,which enables classification and OOD rejection in a unified *** maintain the closed-set classification accuracy of the OVA trained classifier,we propose a hybrid training strategy combining OVA loss and multi-class cross-entropy *** implement the OVA framework and hybrid training strategy on the recently proposed convolutional prototype network and prototype classifier on vision transformer(ViT)*** on popular OSR and OOD detection datasets demonstrate that the proposed framework,using a single multi-class classifier,yields competitive performance in closed-set classification,OOD detection,and misclassification *** code is available at https://***/zhen-cheng121/CPN_OVA_unified.

关键词： Open set recognition out-of-distribution detection misclassification detection convolutional prototype network oneversus-all Dempster-Shafer theory of evidence

Chemically synthesizing exchange-coupled SmCo_(5)/Sm_(2)Co_(17) nanocomposites

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Rare Metals 2021年第3期40卷 575-581页

作者： yao-Hui xu Qiang Jiang Kun Li Zhen-Hui Ma School of Physics and Electronic Engineering Laboratory for Functional MaterialsLeshan Normal UniversityNanjing 211189China Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments School of Mechanical EngineeringSoutheast UniversityNanjing 211189China College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China Department of Chemistry Brown UniversityProvidenceRI 02912USA

A new strategy to chemically synthesize exchange-coupled SmCo_(5)/Sm_(2) Co_(17) nanocomposites by in situ decomposition of SmCox(5 详细信息

A new strategy to chemically synthesize exchange-coupled SmCo_(5)/Sm_(2) Co_(17) nanocomposites by in situ decomposition of SmCox(5

关键词： SmCo_(5) Nanocomposites Exchange coupling Coercivity