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A Robust UWB Array Localization Scheme through Passive Anchor Assistance

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China Communications 2021年第4期18卷 1-13页

作者： Haipeng Lu TianyuWang Feng Ge yuan shen Electronic Engineering department Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Beijing 100084China

Ultra-Wide Bandwidth(UWB)localization based on time of arrival(TOA)and angle of arrival(AOA)has attracted increasing interest owing to its high accuracy and low ***,existing localization methods often fail to achieve satisfactory accuracy in realistic environments due to multipath effects and non-line-of-sight(NLOS)*** this paper,we propose a passive anchor assisted localization(PAAL)scheme,where the active anchor obtains TOA/AOA measurements to the agent while the passive anchors capture the signals from the active anchor and *** proposed method fully exploits the time-difference-of-arrival(TDOA)information from the measurements at the passive anchors to complement single-anchor joint TOA/AOA *** performance limits of the PAAL system are derived as a benchmark via the information ***,we implement the PAAL system on a low-cost UWB platform,which can achieve 20 cm localization accuracy in NLOS environments.

关键词： ultra-wideband localization NLOS environments passive listening adaptive unscented Kalman filter(UKF)

Observation of pentaquark states and prospectives of further studies

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Science Bulletin 2015年第17期60卷 1549-1550页

作者： Cheng-Ping shen Chang-Zheng yuan School of Physics and Nuclear Energy Engineering Beihang University Institute of High Energy Physics Chinese Academy of Sciences

The quark model based on quark–antiquark mesons and three-quark baryons has been very successful in classifying the ***,quantum chromodynamics(QCD)does not forbid the existence of exotic hadronic states with other qu... 详细信息

关键词：五夸克态夸克胶子结构量子色动力学强子态夸克模型反夸克 QCD 杂交种

New advances in the neural correlates of insight: A decade in review of the insightful brain

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Chinese Science Bulletin 2013年第13期58卷 1497-1511页

作者： shen WangBing LUO Jing LIU Chang yuan yuan Laboratory of Cognitive Neuroscience and department of Psychology Nanjing Normal University Key Laboratory of Cognition and Learning Capital Normal University Key Laboratory of Mental Health Chinese Academy of Sciences

The first neuroimaging study of real-time brain activity during insight problem solving was conducted almost ten years ago. Many subsequent studies have used high-resolution event-related potentials (ERPs) and event-related functional magnetic resonance imaging (fMRI) to investigate the temporal dynamics and neural correlates of insight. Recent results on the neural underpinnings of insight have led researchers to propose a neural framework referred to as the "insightful brain". This putative framework represents the neural basis of the cognitive and affective processes that are involved in insight. The insightful brain may involve numerous brain regions, including the lateral prefrontal cortex, cingulate cortex, hippocampus, superior temporal gyrus, fusiform gyrus, precuneus, cuneus, insula and cerebellum. Functional studies have demonstrated that the lateral prefrontal cortex is responsible for mental set shifting and breaking during insight problem solving. The cingulate cortex is involved in the cognitive conflict between new and old ideas and progress monitoring. The hippocampus, superior temporal gyrus and fusiform gyrus form an integrated functional network that specializes in the formation of novel and effective associations. The effective transformation of problem representations depends on a non-verbal visuospatial information-processing network that comprises the precuneus and cuneus. The insula reflects cognitive flexibility and the emotional experience that is associated with insight. The cortical control of finger movements relies on the cerebellum.

关键词：大脑活动神经事件相关电位功能磁共振成像前额叶皮质审查额叶皮层空间信息处理

Study of the thermal influence on the dynamic characteristics of the motorized spindle system

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Advances in Manufacturing 2016年第4期4卷 355-362页

作者： Song-sheng Li yuan shen Qiang He School of Mechatronic Engineering and Automation Shanghai Key Laboratory of Intelligent Manufacturing andRobotics Shanghai University Shanghai 200072People's Republic of China School of Mechanical Engineering Anyang Institute ofTechnology Anyang 455000 HenanPeople's Republic of China

The severe internal heat generation of the motorized spindle system causes uneven temperature dis- tribution, and will affect the vibration characteristics of the system. Based on the thermal analysis about the motorized spindle by finite element method （FEM）, the thermal deformations of the spindle system are calculated by the thermal structure coupling simulation, and the thermal deformations of the rotor and the bearing units are extracted to analyze the bearing stiffness changes so that the modal characteristics of the rotor can be simulated in different thermal state conditions. And then the rotor thermal deformation experiment and the modal experiment of spindle by exciting with hammer are performed. The result shows that the thermal state of the motorized spindle system has a significant influence on the natural frequency of the rotor, which can be carefully treated when a spindle system is designed.

关键词： Motorized spindle Thermal characteristic Thermal-structure coupling Modal analysis Spindlesystem

中药生物碱类成分防治膝骨关节炎的作用与机制

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中国组织工程研究 2025年第11期29卷 2368-2376页

作者：沈栩钰罗承诺章晓云江周影柴源广西中医药大学广西壮族自治区南宁市530011 广西中医药大学附属瑞康医院广西壮族自治区南宁市530011

背景:目前现代医疗手段治疗膝骨关节炎仍具有一定局限性,中药生物碱类成分可通过多种作用机制有效防治膝骨关节炎。目的:对中药生物碱类成分防治膝骨关节炎的作用机制进行综述,为临床开发治疗膝骨关节炎的药物提供科学依据。方法:查阅... 详细信息

背景:目前现代医疗手段治疗膝骨关节炎仍具有一定局限性,中药生物碱类成分可通过多种作用机制有效防治膝骨关节炎。目的:对中药生物碱类成分防治膝骨关节炎的作用机制进行综述,为临床开发治疗膝骨关节炎的药物提供科学依据。方法:查阅中国知网、万方、Pub Med、Web of Science和Google Scholar数据库从建库至2024年5月发表的相关文献,中文检索词为“膝骨关节炎,骨关节炎,破骨细胞,软骨细胞,生物碱”,英文检索词为“knee osteoarthritis,osteoarthritis,osteoclast,chondrocyte,alkaloids”,排除陈旧及无参考意义的文献,最终纳入68篇文献进行综述。结果与结论:虽然中药治疗膝骨关节炎的历史悠久,但仅有少量的天然化合物处于抗膝骨关节炎的临床前研究阶段,生物碱类成分对于防治膝骨关节炎具有较大潜能,其中苦参碱、氧化苦参碱、青藤碱、甜菜碱等已被证实可通过调控多条信号通路抑制炎症反应、抗氧化反应、抑制软骨细胞凋亡、促进软骨细胞增殖、抑制破骨细胞形成与分化等延缓膝骨关节炎的进展。

关键词：膝骨关节炎中药生物碱类信号通路破骨细胞软骨细胞细胞自噬

densification of W-Ni-Cu and W-Fe-Cu Alloys at 1573 K

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Journal of Materials Science & Technology 1999年第1期15卷 94-96页

作者： Xiong, Huaping Zhang, Lianmeng shen, Qiang yuan, Runzhang Wuhan Univ Technol State Key Lab Mat Synth & Proc Wuhan 430070 Peoples R China

The tungsten alloys with Ni-Cu and Fe-Cu additives were sintered at 1573 K for 1 h by hot-pressing method. It was found that the alloy relative density can be improved with the addition of Cu when Cu content is not very high, and W95Ni3Cu2 alloy with full density can be obtained Under the sintering condition. However, with the Cu content further increasing, the relative density change of W-Ni-Cu alloy and W-Fe-Cu alloy shows different trends, the former tends to decrease obviously, but the latter shows little change. According to the analysis results, the element Cu has different effects on the activation capability of Ni and Fe during sintering of the tungsten alloys. (Edited author abstract) 7 Refs.

关键词： Tungsten alloys

RECOVERY OF AMORPHOUS POLY(ETHYLENE TEREPHTHALATE)FILM UNIAXIALLY DRAWN JUST BELOW THE GLASS TRANSITION TEMPERATURE

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Chinese Journal of Polymer Science 2000年第1期18卷 69-75页

作者： Nan-jian Sun Juan Yang de-yan shen Ren-yuan Qian Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China 中科院化学所北京

Isothermal recovery in the macroscopic length of homogeneously deformed specimens of amorphous poly(ethylene terephthalate) (PET) film sample uniaxially drawn at 69 degrees C to the draw ratios lambda(0) = 1.26-2.20 were studied at temperatures around the glass transition temperature (T-g = 73 degrees C). Experimental results indicate that the length recovery look place in two distinct steps: a fast first step (fast relaxation) followed by a slow second step (slow relaxation). The relaxation processes were accompanied by the reversion of trans-conformers (1340 cm(-1)) to gauche, and the dichroic function of the 1340 cm(-1) band characterizing the segmental orientation along the chain direction decreased to a very low value at the end of the fast relaxation. This fact led us to assign the fast relaxation as the segmental orientation while the slow relaxation as relaxation of the global chain orientation. It was found that the slow relaxation follows a single exponential function, with relaxation times strongly dependent on the temperature resembling the glass transition process. The fast relaxation does not follow a single exponential decay, presumably a distribution of relaxation times is involved.

关键词： poly(ethylene terephthalate) uniaxial drawing recovery orientation

A CELL-CENTERED ALE METHOD WITH HLLC-2D RIEMANN SOLVER IN 2D CYLINDRICAL GEOMETRY

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Journal of Computational Mathematics 2021年第5期39卷 666-692页

作者： Jian Ren Zhijun shen Wei Yan Guangwei yuan Institute of Applied Physics and Computational Mathematics Beijing 100088China Center for Applied Physics and Technology HEDPSPeking UniversityBeijing 100081China

This paper presents a second-order direct arbitrary Lagrangian Eulerian(ALE)method for compressible flow in two-dimensional cylindrical *** algorithm has half-face fluxes and a nodal velocity solver,which can ensure the compatibility between edge fluxes and the nodal flow *** two-dimensional cylindrical geometry,the control volume scheme and the area-weighted scheme are used respectively,which are distinguished by the discretizations for the source term in the momentum *** two-dimensional second-order extensions of these schemes are constructed by employing the monotone upwind scheme of conservation law(MUSCL)on unstructured *** results are provided to assess the robustness and accuracy of these new schemes.

关键词： Riemann solver ALE HLLC-2D Cylindrical geometry

Application of Vacuum Drying to Silica Sol Ceramic Mold

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Journal of Materials Science & Technology 2008年第2期24卷 233-235页

作者： Ming ZENG Xinqiang yuan Baoluo shen Yunqiu ZHENG School of Materials Science and Engineering Sichuan University Chengdu 610065 China School of Materials Science and Engineering Shaanxi University of Technology Hanzhong 723003 China School of Materials Science and Engineering Xihua University Chengdu 610039 China department of English Xichang College Xichang 615022 China

Silica sol ceramic mold was made at room temperature with JN-30 silica sol, silica powder and NH4Cl. It is found that the harden time of silica sol ceramic mold is only 0.5 to 1.5 h under the amount of NH4Cl solution of 7% to 8% with 15% concentration, and less surface cracks occur by using vacuum drying. The proper vacuum drying process parameters： vacuum drying temperature is 80 to 100℃, drying time is 5 h and vacuum is 0.06 to 0.07MPa. The harden mechanics, vacuum drying mechanics and the reason of less surface cracks of silica sol ceramic mold by vacuum drying： were also analyzed in this paper.

关键词： Silica sol Ceramic mold Vacuum drying NH4Cl solution