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钛合金支架及其表面处理技术研究进展

中国口腔颌面外科杂志 2024年第5期22卷 505-509页

作者：陶文昊田刚韩煦祝迎春徐晓刚海军军医大学第一附属医院口腔科上海200433 中国科学院上海硅酸盐研究所中国科学院特种无机涂层重点实验室上海200050

3D打印制造出的Ti-6Al-4V多孔支架相比传统的钛合金支架,力学性能更加接近天然骨组织,具有很好的生物相容性,有望成为骨缺损修复的理想材料。为提升钛合金的生物性能,各种表面处理技术应运而生,这些处理技术可分为涂层法和非涂层法,而... 详细信息

3D打印制造出的Ti-6Al-4V多孔支架相比传统的钛合金支架,力学性能更加接近天然骨组织,具有很好的生物相容性,有望成为骨缺损修复的理想材料。为提升钛合金的生物性能,各种表面处理技术应运而生,这些处理技术可分为涂层法和非涂层法,而不同的表面处理技术各有优劣,本文就钛合金支架及其表面处理技术的研究进展进行综述。

关键词： 3D打印多孔钛合金聚多巴胺羟基磷灰石纤维蛋白原 Ⅰ型胶原蛋白成骨软组织封闭

Electronic image stabilization algorithm based on fixed-lag smooth filtering

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Optoelectronics Letters 2007年第4期3卷 308-311页

作者： ZHANG Fan WANG xiao-tong xu xiao-gang YANG Chang-qing DepartmentofNavigation Dalian NavalAcademyDalhTn 116018China Department of Automatization Dalian Naval AcademyDalian 116018China Institute of Photoelec tricTechnology Dalian NavalAcademyDalian 116018China

An algorithm using fixed-lag smooth filtering to improve the precision of EIS algorithm is presented in this paper. Ftrstly, gray projection algorithm （GPA） is used to calculate the interframe global motion vectors. Secondly, the fixed-lag smooth filter is used to smoothen the motion track of the original video sequence, according to different motion models. At last, the original sequence is compensated by using the compensation vectors calculated from filtering. This algorithm has been proved superior in filtering precision by experiments of video sequences in different motion scenes. This algorithm also satisfies the real-time request.

关键词：电子图象稳定性算法光滑滤波

Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and Electronics 2024年第1期35卷 154-162页

作者： ZHANG Ying xiao gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and *** assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same ***,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge *** them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among *** this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness *** purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption

How to build a habitable planet:an interview with Charles H. Langmuir

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National Science Review 2024年第6期11卷 76-80页

作者： Yi-gang xu the Guangzhou Institute of Geochemistry Chinese Academy of Sciences

Earth is the only known habitable planet in the solar system. Understanding how Earth developed its unique habitability has been the frontier of Earth sciences and has become one of the main themes of current deep-space explorations. What are the decisive factors that led to a habitable planet? What is the role of solid Earth processes in the origin of life and in modulating the surface environment? Are Earth’s habitability studies relevant to current challenges that human beings face? These questions have attracted the interest of both scientists and the public alike.

关键词： Earth (planet)

Predictive Analysis of Susceptibility of Different Species to SARS-CoV-2 based on ACE2 Receptors

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Biomedical and Environmental Sciences 2020年第11期33卷 877-881页

作者： xu xiao gang WANG Huan WANG San Ying ZHANG Jing SUN Chuan WEI Ming Xiang YAN Jing MAO Gen Xiang Zhejiang Provincial Key Lab of Geriatrics&Geriatrics Institute of Zhejiang Province Department of GeriatricsZhejiang HospitalHangzhou 310013ZhejiangChina The George Washington University Department of BiostatisticsWashington DC 20052USA

Coronavirus Disease 2019(COVID-19)is a pulmonary inflammatory disease caused by infection with the highly pathogenic new coronavirus(SARSCo V-2)[1].To date,COVID-19 has spread to at least210 countries and territories,infected more than10.94 million people,and killed more than 519,000 people,according to Johns Hopkins *** April 15,2020,the COVID-19 outbreak was declared a global health emergency[2].

关键词： ACE2 Hopkins Receptor

Volatiles in the mantle transition zone and their effects on big mantle wedge systems

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National Science Review 2024年第6期11卷 15-18页

作者： Yu Wang Yi-gang xu State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou)

The mantle transition zone (MTZ), located between the upper and lower mantle, is characterized by sudden seismicvelocity discontinuities at depths of 410 and 660 km where significant change in mineralogical composition occurs. As a link between the upper and lower mantle,the MTZ is a layer of special significance in Earth’s deep structure, and a critical interface in geodynamics and material circulation.

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αDecay in extreme laser fields within a deformed Gamow-like model

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Nuclear Science and Techniques 2024年第2期35卷 131-144页

作者： Qiong xiao Jun-Hao Cheng Yang-Yang xu You-Tian Zou Jun-gang Deng Tong-Pu Yu Department of Physics National University of Defense TechnologyChangsha 410073China College of Science China Three Gorges UniversityYichang 443002China

In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was *** the deformed Gamow-like model, we found that state-of-the-art lasers can cause a slight change in the α decay penetration probability of most nuclei. In addition, we studied the correlation between the rate of change of the α decay penetration probability and angle between the directions of the laser electric field and α particle emission for different nuclei. Based on this correlation, the average effect of extreme laser fields on the half-life of many nuclei with arbitrary α particle emission angles was calculated. The calculations show that the laser suppression and promotion effects on the α decay penetration probability of the nuclei population with completely random α particle-emission directions are not completely *** remainder led to a change in the average penetration probability of the nuclei. Furthermore, the possibility of achieving a higher average rate of change by altering the spatial shape of the laser is explored. We conclude that circularly polarized lasers may be helpful in future experiments to achieve a more significant average rate of change of the α decay half-life of the nuclei population.

关键词： αDecay Deformed Gamow-like model Half-lives Extreme laser field Penetration probability

Surface Polarization Effects on Collapse Transition of Polyelectrolyte Brushes

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Chinese Journal of Polymer Science 2024年第9期42卷 1313-1320,I0006页

作者： xiao-Fei xu State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai200237China

Polyelectrolyte brushes(PEBs)are commonly used to modify surface that have attracted great research *** dielectric permittivity of the grafted surface is typically significantly different from that of solution,which results in surface polarization(SP)effect with a jump of electric *** is thus important to study how SP alters the PEB’s structure and *** this work,the SP effects on PEB structure was studied using a statistical thermodynamic *** free energy functional to describe SP effect was constructed by using the image-charge ***,the electrostatic potential was solved from a modified Poisson-Boltzmann equation taking the ion solvation effect into *** the absence of SP,the thickness of PEB exhibited a continuous collapse transition when decreasing the solvent *** the presence of SP,the collapse became a jump-like *** energy analysis showed that the long-range Coulombic interaction dominated the transition because of the enhanced counterion condensation in the presence of *** theory provides an effective tool to study SP effect on PEBs,and the results explain the underlying physics in PEB collapse transition.

关键词： Surface polarization Polyelectrolyte brush Image charge Ion solvation Polyelectrolyte collapse transition

How to implement a knowledge graph completeness assessment with the guidance of user requirements

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Journal of Systems Engineering and Electronics 2024年第3期35卷 679-688页

作者： ZHANG Ying xiao gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

In the context of big data, many large-scale knowledge graphs have emerged to effectively organize the explosive growth of web data on the Internet. To select suitable knowledge graphs for use from many knowledge graphs, quality assessment is particularly important. As an important thing of quality assessment, completeness assessment generally refers to the ratio of the current data volume to the total data *** evaluating the completeness of a knowledge graph, it is often necessary to refine the completeness dimension by setting different completeness metrics to produce more complete and understandable evaluation results for the knowledge ***, lack of awareness of requirements is the most problematic quality issue. In the actual evaluation process, the existing completeness metrics need to consider the actual application. Therefore, to accurately recommend suitable knowledge graphs to many users, it is particularly important to develop relevant measurement metrics and formulate measurement schemes for completeness. In this paper, we will first clarify the concept of completeness, establish each metric of completeness, and finally design a measurement proposal for the completeness of knowledge graphs.

关键词： knowledge graph completeness assessment relative completeness user requirement quality management