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China to Open State Research Program to Overseas Scientists
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《Bulletin of the Chinese Academy of Sciences》 2000年第3期128-128,共1页
China will open part of its civil projects in national research program, including hi-tech development programs and major basic research programs to overseas scientists, said a senior official with the Ministry of Sci... China will open part of its civil projects in national research program, including hi-tech development programs and major basic research programs to overseas scientists, said a senior official with the Ministry of Science and Technology (MOST). Facing the globalization trend in terms of economy and S&T development, China will take a 展开更多
关键词 open MOST China to open state Research Program to Overseas Scientists
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Reduction in interhemispheric functional connectivity in the dorsal visual pathway in unilateral acute open globe injury patients: a resting-state fMRI study 被引量:3
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作者 Lei Ye Ran Wei +9 位作者 Xin Huang Wen-Qing Shi Qi-Chen Yang Qing Yuan Pei-Wen Zhu Nan Jiang Biao Li Qiong Zhou Fu-Qing Zhou Yi Shao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第6期1056-1060,共5页
This study investigated the changes in interhemispheric functional connectivity (FC) of the whole brain in open globe injury (OGI) patients, using voxel-mirrored homotopic connectivity (VMHC), and their relation... This study investigated the changes in interhemispheric functional connectivity (FC) of the whole brain in open globe injury (OGI) patients, using voxel-mirrored homotopic connectivity (VMHC), and their relationships with clinical features. Totally, 16 male and 2 female acute OGI patients and 18 sex, age, and education-matched healthy volunteers were enrolled in the study. All subjects were scanned through functional magnetic resonance imaging (fMRI). Receiver operating characteristic (ROC) curves analyses had been used to identify the VMHC in these brain areas could be used as biomarkers to distinguish OGI and from healthy control (HC). The mean VMHC values in multiple brain areas and clinical OGI manifestations were evaluated with a Pearson correlation analysis. OGI patients had significantly decreased VMHC in the bilateral calcarine/lingual/cuneus (BA18, 19, 30) and middle occipital gyrus (BA18, 19). The OGI patients had abnormal interhemispheric FC in the dorsal visual pathway, which may represent the pathophysiological mechanism that underlies acute vision loss after OGI. 展开更多
关键词 unilateral acute open globe injury voxelmirrored homotopic connectivity resting state functional magnetic resonance imaging
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Prevalence of Myocilin Gene Mutation in Adult-Onset Primary Open Angle Glaucoma and Non-Glaucoma Subjects Who Are Indigenes of Rivers State, Nigeria
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作者 Azubuike Alfred Onua Chinyere Nnenne Pedro-Egbe 《Open Journal of Ophthalmology》 2023年第1期91-105,共15页
Background: Glaucoma is the leading cause of irreversible blindness incapacitating over 80 million people worldwide. Several pathogenetic mechanisms have been postulated to explain the optic nerve damage that occur in... Background: Glaucoma is the leading cause of irreversible blindness incapacitating over 80 million people worldwide. Several pathogenetic mechanisms have been postulated to explain the optic nerve damage that occur in POAG among which genetic predisposition is prominent. Gene-Linkage-based studies have identified genes associated with POAG: Myocilin, Optineurin, WDR36, Tank-Binding Kinase (TBK1) and APbb-2. Objective: To investigate the prevalence of myocilin gene mutation in adult-onset POAG patients and non-glaucoma subjects who are indigenes of Rivers State. Methodology: In this comparative cross-sectional study, 393 POAG patients attending the Glaucoma Clinic of UPTH were compared with 393 age and sex-matched phenotypically normal participants. Clinical assessment combined with findings from clinical records was used. Venous blood was obtained for genomic analyses. Extracted DNA was sequenced with specific primers for myocilin and polymerase chain reaction. Zymo-Bead Genomic DNA kit protocol was used to detect allelic differences. Results: Total of 786 participants participated in the study. The mean age was 59.8 ± 11.8 years. The prevalence of myocilin gene mutation (MYOC) in the study population was 5.3%, in the POAG group was 8.4%, and 2.3% in the non-glaucoma group. This observed difference was statistically significant (p = 0.001). Location of the mutant myocilin gene was in GLC1A 171638779, 171638703, 171638610 and 171638608. Conclusion: Mutations in myocilin gene are associated with adult-onset POAG in Rivers State. Its relevance as a biomarker for diagnosis of adult-onset POAG needs further investigations. 展开更多
关键词 PREVALENCE Myocilin Gene Mutation Adult-Onset Primary open Angle Glaucoma Rivers state Indigenes
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Analysis of the Flow of a Molten Slag in an Open Channel Using Transient and Steady-State Solutions of the Saint-Venant Equations
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作者 Miguel A. Barron Joan Reyes Aristeo Garrido 《World Journal of Engineering and Technology》 2024年第4期976-986,共11页
In recent years, metallurgical slags have been increasingly used as materials for the manufacture of cement, pavement and filling material. The transport of the molten slag to the receiving pots is carried out through... In recent years, metallurgical slags have been increasingly used as materials for the manufacture of cement, pavement and filling material. The transport of the molten slag to the receiving pots is carried out through open channels. The transient and steady-state flow of a molten slag in a rectangular open channel is numerically analyzed here. For the transient flow, the Saint-Venant equations were numerically solved. For the steady-state flow, the derivatives in time and space in the Saint-Venant equations were set equal to zero and a polynomial of degree 3 is obtained whose roots are the slag height values. It was assumed that the viscosity of the slag has an Arrhenius-type behavior with temperature. Four values of temperature values, namely 1723.15, 1773.15, 1823.15, 18873.15 ˚K, and five values of the angle of inclination of the channel, namely 1, 2, 3, 4, 5 degrees, are considered. Numerical results show that the steady-state values of the height and velocity of the molten slag depend strongly on the temperature of the slag and the angle of inclination of the channel. As the slag temperature and channel angle increase, the value of the steady-state slag height decreases. The value of the steady-state slag velocity increases as the slag temperature and channel inclination angle increase. 展开更多
关键词 Molten Slag open Channel Phase-Portrait Saint-Venant Equations Steady state Transient Solution
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五相永磁同步电动机无模型预测容错控制
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作者 周华伟 朱流川 +1 位作者 周振伍 颜黎浩 《江苏大学学报(自然科学版)》 北大核心 2026年第1期71-78,共8页
针对开路故障下运行时五相永磁同步电动机参数易发生摄动,严重影响模型预测电流控制性能的问题,提出一种新的无模型预测容错控制策略.在同步旋转坐标系中建立五相永磁同步电动机相开路故障情况下的模型,分析由参数摄动及未建模动态引起... 针对开路故障下运行时五相永磁同步电动机参数易发生摄动,严重影响模型预测电流控制性能的问题,提出一种新的无模型预测容错控制策略.在同步旋转坐标系中建立五相永磁同步电动机相开路故障情况下的模型,分析由参数摄动及未建模动态引起的总扰动.基于超局部模型,在基波和三次谐波平面中设计扩展状态观测器估计扰动,并将其补偿到基于无差拍控制得到的参考电压中.在MATLAB/Simulink中搭建基于五相PMSM的MF-PFTC模型,并与传统MPFTC进行性能对比仿真分析.建立五相PMSM试验平台,分别对传统MPFTC策略和所提出MF-PFTC策略进行相关试验.结果表明:所提出方法在正常和开路故障情况下均具备优良的稳态、动态和鲁棒性能,验证了所提出策略的有效性. 展开更多
关键词 永磁同步电动机 无模型预测控制 容错控制 开路故障 参数失配 超局部模型 扩展状态观测器
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基于Open XML和有限自动机的试卷自动生成系统
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作者 林晓 吴为民 刘勇峰 《顺德职业技术学院学报》 2023年第3期38-43,共6页
考试出题讲究高保密性和高时效性,不允许将题目事先导入数据库再自动生成试卷,需要现场从大量的WORD文档中直接抽取题目并排版生成试卷,这是一项耗时耗力的工作。本研究利用Open XML文档的开源性,直接对DOCX和XLSX文档的内容进行分析读... 考试出题讲究高保密性和高时效性,不允许将题目事先导入数据库再自动生成试卷,需要现场从大量的WORD文档中直接抽取题目并排版生成试卷,这是一项耗时耗力的工作。本研究利用Open XML文档的开源性,直接对DOCX和XLSX文档的内容进行分析读取,并利用有限状态自动机原理对文档的内容进行分类处理,自动生成试卷、答案卷和答题卡文档。实验表明这种方法能够正确按照要求生成试卷,既解决了考试中的保密性要求又提高了工作效率,节省了人力成本。 展开更多
关键词 open XML标准 有限自动机 试卷自动生成
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新《档案法》背景下国有企业档案开放审核机制构建
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作者 尚广鸶 《山西档案》 北大核心 2026年第1期53-56,共4页
在新《档案法》实施的背景下,国有企业档案开放工作面临权责界限模糊、协同效率低下与安全风险突出的多重挑战。立足新法语境与国有企业治理实际,系统剖析国有企业档案开放审核的权责冲突、价值风险对峙及传统机制失效的深层原因,构建... 在新《档案法》实施的背景下,国有企业档案开放工作面临权责界限模糊、协同效率低下与安全风险突出的多重挑战。立足新法语境与国有企业治理实际,系统剖析国有企业档案开放审核的权责冲突、价值风险对峙及传统机制失效的深层原因,构建了涵盖“全生命周期风险治理—分类审核架构—协同审核共同体—动态评估复审”的系统框架,旨在为推动国有企业档案治理现代化提供制度创新与技术支撑。 展开更多
关键词 新《档案法》 国有企业 档案开放 审核机制 风险治理
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A Comparative Study on Open Circuit Voltage Models for Lithium-ion Batteries 被引量:10
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作者 Quan-Qing Yu Rui Xiong +1 位作者 Le-Yi Wang Cheng Lin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第4期84-91,共8页
The current research of state of charge(SoC) online estimation of lithium-ion battery(LiB) in electric vehicles(EVs)mainly focuses on adopting or improving of battery models and estimation filters. However, little att... The current research of state of charge(SoC) online estimation of lithium-ion battery(LiB) in electric vehicles(EVs)mainly focuses on adopting or improving of battery models and estimation filters. However, little attention has been paid to the accuracy of various open circuit voltage(OCV) models for correcting the SoC with aid of the ampere-hour counting method. This paper presents a comprehensive comparison study on eighteen OCV models which cover the majority of models used in literature. The low-current OCV tests are conducted on the typical commercial LiFePO/graphite(LFP) and LiNiMnCoO/graphite(NMC) cells to obtain the experimental OCV-SoC curves at different ambient temperature and aging stages. With selected OCV and SoC points from experimental OCV-SoC curves, the parameters of each OCV model are determined by curve fitting toolbox of MATLAB 2013. Then the fitting OCV-SoC curves based on diversified OCV models are also obtained. The indicator of root-mean-square error(RMSE) between the experimental data and fitted data is selected to evaluate the adaptabilities of these OCV models for their main features, advantages,and limitations. The sensitivities of OCV models to ambient temperatures, aging stages, numbers of data points,and SoC regions are studied for both NMC and LFP cells. Furthermore, the influences of these models on SoC estimation are discussed. Through a comprehensive comparison and analysis on OCV models, some recommendations in selecting OCV models for both NMC and LFP cells are given. 展开更多
关键词 state of charge open circuit voltage model Lithium-ion battery NMC LFP
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TRANSIENT-STATE RESPONSE OF WAVE PROPAGATION IN MAGNETO-ELECTRO-ELASTIC SQUARE COLUMN 被引量:2
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作者 Jianping Wei Xianyue Su 《Acta Mechanica Solida Sinica》 SCIE EI 2008年第6期491-499,共9页
This is a continued work in studying the wave propagation in a magneto-electroelastic square column (MEESC). Based on the analytic dispersive equation, group velocity equation and steady-state response obtained in o... This is a continued work in studying the wave propagation in a magneto-electroelastic square column (MEESC). Based on the analytic dispersive equation, group velocity equation and steady-state response obtained in our previous paper 'Steady-state response of the wave propagation in a magneto-electro-elastic square column' published in CME, the dynamical behavior of MEESC was studied in this paper. The unlimited column is an open system. The transientstate response in the open system subjected by arbitrary external fields was derived when the propagating wave pursuing method was introduced. 展开更多
关键词 magneto-electro-elastic square column open system transient-state response propagating wave pursuing method
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OPEN ARCHITECTURE CNC SYSTEM HITCNC AND KEY TECHNOLOGY 被引量:4
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作者 WANG Yongzhang LIU Tao FU Hongya HAN Zhenyu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第2期13-16,共4页
Aiming at the characteristics of modularity and reconfigurable in open architecture computer numerical control (CNC) system, the open architecture CNC system, Harbin Institute of Tech- nology computer numerical cont... Aiming at the characteristics of modularity and reconfigurable in open architecture computer numerical control (CNC) system, the open architecture CNC system, Harbin Institute of Tech- nology computer numerical control (HITCNC), is researched and manufactured based on the interface standards. The system's external interfaces are coincident with the corresponding international standards, and the internal interfaces follow the open modular architecture controller (OMAC) agreement. In the research and manufacturing process, object-oriented technology is used to ensure the openness of the HITCNC, and static programming is applied in the CNC system according to the idea of modularization disassembly. The HITCNC also actualizes real-time and unreal-time modules adopting real-time dynamical linked library (RTDLL) and component object model (COM). Finite state ma- chine (FSM) is adopted to do dynamically modeling of HITCNC. The complete separation between the software and the hardware is achieved in the HITCNC by applying the SoftSERCANS technique. The application of the above key techniques decreases the programming workload greatly, and uses software programs replacing hardware functions, which offers plenty technique ensures for the openness of HITCNC. Finally, based on the HITCNC, a three-dimensional milling system is established. On the system, series experiments are done to validate the expandability and interchangeability of HITCNC. The results of the experiments show that the established open architecture CNC system HITCNC is correct and feasible, and has good openness. 展开更多
关键词 Harbin Institute of Technology computer numerical control(HITCNC) open architecture CNC system Interface standard Statically modeling Finite state machine (FSM) SoflSERCANS
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Analysis of Selecting Gated Community as Opening Its Micro-Inter-Road Network
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作者 Lin Dong Akira Rinoshika Zhixian Tang 《Engineering(科研)》 2018年第7期357-367,共11页
The opening of gated community to expand the micro-road network in the urban traffic system is a hot topic on the urban congestion. To satisfy the demand of opening early choosing case, this paper proposed a comprehen... The opening of gated community to expand the micro-road network in the urban traffic system is a hot topic on the urban congestion. To satisfy the demand of opening early choosing case, this paper proposed a comprehensive selecting framework on qualified communities and its appropriate opening time. Firstly, the static influential factors on internal road structure, boundary road structure and traffic flow are qualitatively analyzed. Then, an evaluation opening state index system based on describing accurately traffic flow state is obtained, which takes the opening factors into account at the boundary road network. In this structure, the modified fuzzy C-means (FCM) method calculates the fuzzy entropy weight and range of each opening states index. Finally, the simulation results show that the proposed method is capable of selecting qualified community and the optimum opening time. 展开更多
关键词 openING GATED Community openING state Index System FUZZY C-MEANS (FCM) Clustering FUZZY Entropy WEIGHT
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EXACT SOLUTION FOR LAMINATED CONTINUOUSOPEN CYLINDRICAL SHELLS
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作者 盛宏玉 范家让 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第11期0-0,0-0+0-0+0-0+0-0+0-0+0-0,共14页
Discarding any assumption about displacement models and stress distribution andintroducing δ-function into the present study, we established the state equation for thecontinuous orthotropic open cylindrical shells. A... Discarding any assumption about displacement models and stress distribution andintroducing δ-function into the present study, we established the state equation for thecontinuous orthotropic open cylindrical shells. An thentical exocl solution is presentedfor the statics of thin. moderately thick and thick laminated continuous openrylindrical shells. Numerical results are obtained and compared with those calculatedusing SAP5. 展开更多
关键词 laminated continuous open cylindrical shell ORTHOTROPY state equation exact solution
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从脑白质病神经血管单元探讨开通玄府法内涵 被引量:1
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作者 吴巍 黄世敬 +1 位作者 杨戈 潘菊华 《长春中医药大学学报》 2025年第2期127-131,共5页
通过对脑白质病神经血管单元与玄府理论的归纳和分析,发现脑玄府与脑白质病神经血管单元在结构和功能上呈现出一定的相关联性,并且脑白质病神经血管单元及其功能障碍与脑白质病不同阶段脑玄府开阖功能受损具有相似性。开通玄府法可应用... 通过对脑白质病神经血管单元与玄府理论的归纳和分析,发现脑玄府与脑白质病神经血管单元在结构和功能上呈现出一定的相关联性,并且脑白质病神经血管单元及其功能障碍与脑白质病不同阶段脑玄府开阖功能受损具有相似性。开通玄府法可应用在脑白质病各个阶段的治疗中,且开通玄府法具有维护脑神经血管单元和促进神经功能康复的作用。脑白质病神经血管单元稳态可以阐述开通玄府法的内涵,并为脑白质病的中医治疗提供了新思路。 展开更多
关键词 脑白质病 神经血管单元 稳态 开通玄府法
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基于CAPE-OPEN标准的萃取精馏过程模拟研究
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作者 张裕凯 张衍壮 +1 位作者 陈玉石 项曙光 《当代化工》 CAS 2018年第11期2372-2376,2380,共6页
萃取精馏过程模拟计算对工业生产具有重要指导作用,为进行基于CAPE-OPEN标准的萃取精馏过程模拟研究,首先了解其处理体系的特点,确定萃取精馏塔功能建立其数学模型,采用内外层算法进行求解计算;然后,使用VisualC++与COM组件思想对模块... 萃取精馏过程模拟计算对工业生产具有重要指导作用,为进行基于CAPE-OPEN标准的萃取精馏过程模拟研究,首先了解其处理体系的特点,确定萃取精馏塔功能建立其数学模型,采用内外层算法进行求解计算;然后,使用VisualC++与COM组件思想对模块进行开发;最后,采用苯-环己烷和四氢呋喃-水两个体系进行测试。将主要工艺参数同Aspen Plus化工模拟软件的计算结果对比,结果表明萃取精馏塔各平衡级的组成、流量和温度分布等参数结果准确可靠,满足分离指标,证明了该单元模块可用于萃取精馏过程模拟研究。 展开更多
关键词 萃取精馏塔 稳态模拟 改进内外层法 CAPE—open
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基于步行路径的山地城区绿色开放空间供需评价与优化研究
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作者 罗丹 张沂珊 +2 位作者 罗融融 李波 杨鑫秀 《中国园林》 北大核心 2025年第2期55-62,共8页
山地城市高密度建成区域具有更加复杂和特殊的用地条件与交通状况,与平坦城市相比存在更突出的空间分布不均衡的问题,绿色开放空间供需状况可能失衡,影响居民福祉。依托步行可达性构建具有山地适宜性的供需评价模型,选取两步移动搜索法... 山地城市高密度建成区域具有更加复杂和特殊的用地条件与交通状况,与平坦城市相比存在更突出的空间分布不均衡的问题,绿色开放空间供需状况可能失衡,影响居民福祉。依托步行可达性构建具有山地适宜性的供需评价模型,选取两步移动搜索法,从供给、需求、供需过程改进评价指标,并以重庆渝中区为例探讨实际供需状况。结果表明,研究区绿色开放空间供需水平呈现较明显的空间分异,高水平区域具有集中式分布、随距离递减的特征;不同类型绿色开放空间供需水平及其提供有效服务的效率均存在差异,城市级绿色开放空间主导供需空间格局,片区级和社区级绿色开放空间服务效率相对更好;供需水平随步行路网密度增加,先提高后降低,且与路径绕路系数具有显著负相关。基于实际供需评价结果,以增加供给效率为目标,提出完善整体布局和优化供需连接的提升策略,为存量背景下的山地城市绿色开放空间规划提供决策依据,为同类城市空间服务效益评价提供参考。 展开更多
关键词 风景园林 山地高密度城区 绿色开放空间 步行可达性 供需状态
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全国重点实验室开放课题管理与运行探索 被引量:1
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作者 徐丹 朱峰 王艺博 《实验技术与管理》 北大核心 2025年第6期257-263,共7页
全国重点实验室是国家创新体系的重要组成部分,开放课题则是实验室开展学术交流、团队合作的重要举措。该文总结了多个国家重点实验室开放课题管理办法与措施,以超硬材料国家重点实验室为例,详述了其通过加强宣传、规范管理、按需设立... 全国重点实验室是国家创新体系的重要组成部分,开放课题则是实验室开展学术交流、团队合作的重要举措。该文总结了多个国家重点实验室开放课题管理办法与措施,以超硬材料国家重点实验室为例,详述了其通过加强宣传、规范管理、按需设立课题等举措提升开放课题管理成效的实践经验。围绕国家对全国重点实验室的新要求,该文提出优化建议:一是在开放课题中设置后补助项目,实践有组织科研范式改革;二是设置国家重大科技基础设施用户专项,提升设施开放共享水平;三是面向本地成果转化项目,提升科技转化效能并赋能区域创新建设。 展开更多
关键词 开放课题 全国重点实验室 课题管理
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美国政府科研数据管理政策的演进与实践——科学开放与国家安全的持续角力与平衡
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作者 仲平 《全球科技经济瞭望》 2025年第8期22-29,共8页
自第二次世界大战以来,美国的科研数据获取和共享政策在科学本身的开放性及政府数据公开透明化双重驱动下逐步发展、完善和健全,确立了“科学开放是基础、安全是必要、自由和诚信是关键”的科研数据管理理念,并建立了较为完备的三级政... 自第二次世界大战以来,美国的科研数据获取和共享政策在科学本身的开放性及政府数据公开透明化双重驱动下逐步发展、完善和健全,确立了“科学开放是基础、安全是必要、自由和诚信是关键”的科研数据管理理念,并建立了较为完备的三级政策规范与管理体系。以历史视角,梳理美国联邦政府科研数据管理政策的发展演进,包括美国相关政策在“数据开放共享”与“研究安全保护”间的数次角力;以现实视角,结合美国联邦政府最大的科学研究资助部门—国家科学基金会(National Sienc Fundation,NSF)等分析相关政策要求和具体实践,以期为中国科研数据管理和国际创新合作提供参考。 展开更多
关键词 美国 科研数据 数据管理 开放科学 开放获取 FAIR原则
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某复垦露天坑境界矿柱稳定性分析
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作者 彭晨鑫 黄德镛 +2 位作者 段泽锋 史凯东 陈治宇 《有色金属(中英文)》 北大核心 2025年第5期863-869,共7页
境界矿柱的稳定性是影响地下采场安全的重要因素,露天转地下开采过程中矿山境界矿柱的稳定对矿山的安全生产十分重要。以云南某铜矿为研究背景,该铜矿有复垦土层,境界矿柱的厚度为28 m,运用FLAC3D三维软件进行模拟分析。结果表明,境界... 境界矿柱的稳定性是影响地下采场安全的重要因素,露天转地下开采过程中矿山境界矿柱的稳定对矿山的安全生产十分重要。以云南某铜矿为研究背景,该铜矿有复垦土层,境界矿柱的厚度为28 m,运用FLAC3D三维软件进行模拟分析。结果表明,境界矿柱发生的最大竖直位移值为4.5 cm,最大拉应力为0.34 MPa,境界矿柱为稳定状态。同时使用K.B.鲁别涅依他公式法得到理论安全厚度为21.65 m,使用结构力学法计算得到理论安全厚度为21.61 m。矿山平均采场跨度为35 m的情况下,境界矿柱处于稳定状态,满足矿山安全生产的要求,为矿山境界矿柱设计施工提供科学指导,同时为相类似矿山提供一定的借鉴经验。 展开更多
关键词 复垦露天坑 境界矿柱 稳定性分析 数值模拟
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基于误差状态扩展卡尔曼滤波的GNSS/INS组合导航机载车载船载数据集 被引量:2
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作者 尹智慧 党龙飞 +1 位作者 魏峥嵘 王胜利 《全球定位系统》 2025年第1期9-17,共9页
针对直接采用扩展卡尔曼滤波(extended Kalman filter,EKF)可能导致精度损失以及出现万向节死锁的情况,本文采用具有良好线性特性的基于误差状态扩展卡尔曼滤波(error state Kalman filter,ESKF)的方法进行GNSS与惯性导航系统(inertial ... 针对直接采用扩展卡尔曼滤波(extended Kalman filter,EKF)可能导致精度损失以及出现万向节死锁的情况,本文采用具有良好线性特性的基于误差状态扩展卡尔曼滤波(error state Kalman filter,ESKF)的方法进行GNSS与惯性导航系统(inertial navigation system,INS)组合导航解算,并将解算结果与高精度解算软件Inertial Explorer(IE)进行对比分析.为了验证方法的有效性,制作并公开了3组组合导航数据集,分别为车载、机载以及船载数据.该数据集的INS设备均采用霍尼韦尔的HG4930,GNSS数据的采样频率分别有车载的5 Hz和机载的1 Hz以及船载的10 Hz.本文将基于ESKF方法在公开的数据集上进行实验,并与IE软件得到的结果进行对比与分析. 展开更多
关键词 GNSS 惯性导航系统(INS) 扩展卡尔曼滤波(EKF) 公开数据集 误差状态扩展卡尔曼滤波(ESKF)
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美国科研安全政策的发展演变、特点及启示
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作者 韩文艳 熊永兰 《智库理论与实践》 北大核心 2025年第5期58-68,共11页
[目的/意义]在科技安全日益渗透国家安全各领域的背景下,梳理并分析美国科研安全政策及其未来走向,能够为新形势下中国构建科研安全体系、维护科技安全提供参考。[方法/过程]本文运用网络与文献调研法、内容分析法等方法系统分析美国科... [目的/意义]在科技安全日益渗透国家安全各领域的背景下,梳理并分析美国科研安全政策及其未来走向,能够为新形势下中国构建科研安全体系、维护科技安全提供参考。[方法/过程]本文运用网络与文献调研法、内容分析法等方法系统分析美国科研安全相关的政策文件,重点聚焦美国科研安全政策的演进脉络、当前的核心关切领域、关键特点及未来可能走向。[结果/结论]美国科研安全政策的发展历程分为三个阶段,目前内容主要聚焦披露要求、国外人才招聘计划、科研安全培训和计划、信息共享和风险评估四个关键领域。政策演变呈现动态化政策演进、网络化协同治理、差异化国际合作、定向化对华遏制等特点,未来政策走向可能会学科精准化、伙伴差异化、部门协作化、监管严格化。最后,本文从政策体系、预警防范、人才队伍、科研合作等方面提出建议。 展开更多
关键词 科技安全 科研安全 基础研究 开放合作 美国
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