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基于Guided BERTopic模型的产业链关键核心技术识别与发展趋势研判--以未来工业互联网为例
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作者 陈升 杨恒 张楠 《科学管理研究》 北大核心 2024年第3期35-44,共10页
产业链关键核心技术不仅是国之重器,而且对推动我国经济的高质量发展和保障国家安全起着至关重要的作用。当前,工业互联网产业链的关键技术发展成为我国的研究重点,该领域的重要性在2023年被提升至国家级重大研究计划。综合收集了1989-2... 产业链关键核心技术不仅是国之重器,而且对推动我国经济的高质量发展和保障国家安全起着至关重要的作用。当前,工业互联网产业链的关键技术发展成为我国的研究重点,该领域的重要性在2023年被提升至国家级重大研究计划。综合收集了1989-2024年中美两国在工业互联网领域的专利数据,基于《关键和新兴技术清单》和《未来工业互联网基础理论与关键技术重大研究计划》,构建了一套工业互联网产业链核心关键技术的种子词库。利用Guided BERTopic模型提取了产业链关键技术主题,并采用Logistic模型评估了这些技术的生命周期,进而对比中美两国的发展情况,提出了针对未来发展的建议。研究结果表明,相比美国,我国在大多数产业链核心技术方面仍处于成长阶段,而美国则已步入技术饱和阶段。展望未来,设备监测系统、设备管理系统、无线通信技术及能耗监测分析系统等被认为是具有巨大发展潜力的技术。研究提出了一种基于政策文件的产业链关键技术识别方法,并通过对工业互联网专利技术的实证分析,为制定相关政策提供了科学指导和建议。 展开更多
关键词 guided BERTopic模型 产业链核心关键技术 工业互联网 中美比较 专利文本 LOGISTIC模型
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Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence 被引量:1
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作者 Jiazhen ZHAO Shengping HE +2 位作者 Ke FAN Huijun WANG Fei LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1465-1482,共18页
Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Ar... Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. Here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions scenario.Thereafter, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained). 展开更多
关键词 wintertime newly formed Arctic sea ice model democracy model weighting scheme model performance model independence
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Guided Care护理模式对老年骨质疏松症患者自我管理能力和生活质量的影响
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作者 周晓英 袭玉荣 《中外医疗》 2024年第16期169-173,共5页
目的探讨分析Guided Care护理模式对老年骨质疏松症患者自我管理能力和生活质量的影响。方法简单随机选取2022年1月—2023年9月山东省泰安荣军医院收治的60例老年骨质疏松症患者为研究对象,按随机数表法将其分为常规组(实施常规护理干... 目的探讨分析Guided Care护理模式对老年骨质疏松症患者自我管理能力和生活质量的影响。方法简单随机选取2022年1月—2023年9月山东省泰安荣军医院收治的60例老年骨质疏松症患者为研究对象,按随机数表法将其分为常规组(实施常规护理干预),模式组(在常规组的基础上给予Guided Care护理模式干预),每组30例,两组均持续干预2个月,比较两组患者干预前后的健康认知水平、跌倒风险、自我管理能力、生活质量、护理满意度。结果干预2个月后,模式组的健康认知水平评分高于常规组,差异有统计学意义(P<0.05)。干预2个月后,模式组的跌倒风险评分低于常规组,差异有统计学意义(P<0.05)。干预2个月后,模式组的自我管理能力评分高于常规组,生活质量评分低于常规组,差异有统计学意义(P均<0.05)。干预2个月后,模式组的护理满意度为93.33%,高于常规组的护理满意度73.33%,差异有统计学意义(χ^(2)=4.320,P<0.05)。结论在老年骨质疏松症患者中,应用Guided Care护理模式,可以有效地提升患者的健康认知水平及自我管理能力,提高患者的生活质量,降低患者跌倒的风险。 展开更多
关键词 guided Care护理模式 老年骨质疏松症 自我管理能力 生活质量
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GUIDE FOR AUTHORS
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《Nano Materials Science》 EI CAS CSCD 2024年第2期I0003-I0006,共4页
Article Article types Articles commonly fall into one of three main categories:Full-length articles,Review articles and Short communications.Full-length articles are original,unpublished primary research.Extensions of... Article Article types Articles commonly fall into one of three main categories:Full-length articles,Review articles and Short communications.Full-length articles are original,unpublished primary research.Extensions of work that has been published previously in short form such as a Communication are usually acceptable. 展开更多
关键词 EXTENSION acceptable guide
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《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期I0002-I0005,共4页
Introduction Types of paper Contributions falling into the following categories will be considered for publication: Original research papers, reviews, Research Notes, Short Communication, New technologies, News and Vi... Introduction Types of paper Contributions falling into the following categories will be considered for publication: Original research papers, reviews, Research Notes, Short Communication, New technologies, News and Views, Commentary on significant events and topics in global horticultural fields with international interests. 展开更多
关键词 NOTES INTERESTS guide
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《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第2期I0002-I0005,共4页
Introduction Types of paper Contributions falling into the following categories will be considered for publication:Original research papers,reviews,perspectives,news and views,case reports,letters.
关键词 LETTERS guide FALLING
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《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第3期I0002-I0005,共4页
Introduction Typesof paper Contributions falling into the following categories will be considered for publication:Original research papers,reviews,perspectives,news and views,case reports,letters.
关键词 LETTERS guide FALLING
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《Earthquake Research Advances》 CSCD 2024年第2期83-89,共7页
INTRODUCTION.Types of paper.Contributions falling into the following categories will be considered for publication:Original research papers,reviews and short communications.Please ensure that you select the appropriat... INTRODUCTION.Types of paper.Contributions falling into the following categories will be considered for publication:Original research papers,reviews and short communications.Please ensure that you select the appropriate article type from the list of options when making your submission.Authors contributing to special issues should ensure that they select the special issue article type from this list. 展开更多
关键词 SUBMISSION contributing guide
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《Earthquake Research Advances》 CSCD 2024年第1期78-84,共7页
INTRODUCTION Types of paper Contributions falling into the following categories will be considered for publication:Original research papers,reviews and short communications.Please ensure that you select the appropriat... INTRODUCTION Types of paper Contributions falling into the following categories will be considered for publication:Original research papers,reviews and short communications.Please ensure that you select the appropriate article type from the list of options when making your submission.Authors contributing to special issues should ensure that they select the special issue article type from this list. 展开更多
关键词 SUBMISSION contributing guide
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《Earthquake Research Advances》 CSCD 2024年第3期95-101,共7页
INTRODUCTION Types of paper Contributions falling into the following categories will be considered for publication:Original research papers, reviews and short communications.Please ensure that you select the appropria... INTRODUCTION Types of paper Contributions falling into the following categories will be considered for publication:Original research papers, reviews and short communications.Please ensure that you select the appropriate article type from the list of options when making your submission. Authors contributing to special issues should ensure that they select the special issue article type from this list. 展开更多
关键词 SUBMISSION contributing guide
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Pipeline thickness estimation using the dispersion of higher-order SH guided waves
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作者 代政辰 刘金霞 +3 位作者 龙云飞 张建海 Tribikram Kundu 崔志文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期389-396,共8页
Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thi... Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thickness measurement limits its widespread application. This paper proposes a method that utilizes cylindrical shear horizontal(SH) guided waves to estimate pipeline thickness without prior knowledge of shear wave velocity. The inversion formulas are derived from the dispersion of higher-order modes with the high-frequency approximation. The waveform of the example problems is simulated using the real-axis integral method. The data points on the dispersion curves are processed in the frequency domain using the wave-number method. These extracted data are then substituted into the derived formulas. The results verify that employing higher-order SH guided waves for the evaluation of thickness and shear wave velocity yields less than1% error. This method can be applied to both metallic and non-metallic pipelines, thus opening new possibilities for health monitoring of pipeline structures. 展开更多
关键词 pipeline wall thickness higher-order modes SH guided waves DISPERSION
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国外高校图书馆人工智能素养教育调查研究——基于人工智能LibGuide的分析
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作者 宰冰欣 叶兰 胡燕菘 《大学图书馆学报》 北大核心 2024年第4期58-68,共11页
人工智能对高校图书馆信息素养教育提出了新的挑战与更高要求。LibGuide作为开展信息素养教育的一种重要途径,目前已在国外高校图书馆的信息素养教育中被广泛应用。文章调研了40所国外一流高校图书馆,并选取其中创建有人工智能LibGuide... 人工智能对高校图书馆信息素养教育提出了新的挑战与更高要求。LibGuide作为开展信息素养教育的一种重要途径,目前已在国外高校图书馆的信息素养教育中被广泛应用。文章调研了40所国外一流高校图书馆,并选取其中创建有人工智能LibGuide的26所高校图书馆为样本,分析其LibGuide建设特点,并从人工智能知识、人工智能使用、人工智能信息引用、人工智能思维、人工智能伦理五个角度分析了人工智能LibGuide的内容要素。基于调查结果,从加强图书馆在AI素养教育中的作用、建立完善的AI素养教育内容体系、针对不同对象或应用场景开展AI素养教育、丰富AI素养教育形式等方面,为我国高校图书馆开展AI素养教育提出相关建议。 展开更多
关键词 人工智能素养 AI素养 人工智能 高校图书馆 Libguide
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《Journal of Road Engineering》 2024年第1期I0005-I0009,共5页
Introduction Types of paper Contributions falling into the following categories will be considered for publication:Original research papers,Reviews,Short communication.Please ensure that you select the appropriate art... Introduction Types of paper Contributions falling into the following categories will be considered for publication:Original research papers,Reviews,Short communication.Please ensure that you select the appropriate article type from the list of options when making your submission.Authors contributing to special issues should ensure that they select the special issue article type from this list. 展开更多
关键词 SUBMISSION contributing guide
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《Journal of Road Engineering》 2024年第2期I0005-I0009,共5页
Introduction Types of paper Contributions falling into the following categories will be considered for publication:Original research papers,Reviews,Short communication.Please ensure that you select the appropriate art... Introduction Types of paper Contributions falling into the following categories will be considered for publication:Original research papers,Reviews,Short communication.Please ensure that you select the appropriate article type from the list of options when making your submission.Authors contributing to special issues should ensure that they select the special issue article type from this list. 展开更多
关键词 SUBMISSION contributing guide
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Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing
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作者 Jay Kumar Shah Hao Wang Said El-Hawwat 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期319-329,共11页
Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.The growth of internal cracks in PE pipe seve... Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.The growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance strategies.This study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE pipe.Laboratory experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch configuration.Mode dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack growth.The findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth. 展开更多
关键词 polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling
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Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints
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作者 Ning Liu Wenjiang Zhao +4 位作者 Yao Wang Kai Shen Zhong Su Wenhao Qi Yuedong Xie 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期155-170,共16页
In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this pr... In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail spin reduction. After analyzing the mechanism of the ammunition's tail spin reduction, a navigation method of large scale difference tail control simple guided ammunition based on speed constraint is proposed. In this method,the corresponding navigation constraints can be carried out by combining the rotation speed state of the ammunition itself, and the optimal solution of navigation parameters during the flight of the missile can be obtained by Extended Kalman Filter(EKF). Finally, the performance of the proposed method was verified by the simulation environment, and the hardware-in-the-loop simulation test and flight test were carried out to verify the performance of the method in the real environment. The experimental results show that the proposed method can achieve the optimal estimation of navigation parameters for simple guided ammunition with large-scale difference tail control. Under the conditions of simulation test and hardware-in-loop simulation test, the position and velocity errors calculated by the method in this paper converged. Under the condition of flight test, the spatial average error calculated by the method described in this paper is 6.17 m, and the spatial error of the final landing point is 3.50 m.Through this method, the accurate acquisition of navigation parameters in the process of projectile launching is effectively realized. 展开更多
关键词 guided projectiles Tail spin reduction RPM constraints Combined navigation Extended Kalman filter(EKF)
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Role of endoscopic ultrasound-guided biliary drainage for palliation of malignant biliary obstruction
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作者 Sahib Singh Saurabh Chandan Antonio Facciorusso 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2369-2373,共5页
Endoscopic ultrasound-guided biliary drainage(EUS-BD)directs bile flow into the digestive tract and has been mostly used in patients with malignant biliary obstruction(MBO)where endoscopic retrograde cholangiopancreat... Endoscopic ultrasound-guided biliary drainage(EUS-BD)directs bile flow into the digestive tract and has been mostly used in patients with malignant biliary obstruction(MBO)where endoscopic retrograde cholangiopancreatography-guided biliary drainage was unsuccessful or was not feasible.Lumen apposing metal stents(LAMS)are deployed during EUS-BD,with the newer electrocautery-enhanced LAMS reducing procedure time and complication rates due to the inbuilt cautery at the catheter tip.EUS-BD with electrocautery-enhanced LAMS has high technical and clinical success rates for palliation of MBO,with bleeding,cholangitis,and stent occlusion being the most common adverse events.Recent studies have even suggested comparable efficacy between EUS-BD and endosc-opic retrograde cholangiopancreatography as the primary approach for distal MBO.In this editorial,we commented on the article by Peng et al published in the recent issue of the World Journal of Gastrointestinal Surgery in 2024. 展开更多
关键词 Endoscopic ultrasound Endoscopic ultrasound guided biliary drainage CANCER PANCREAS Bile duct ENDOSCOPY
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Intraoperative application of three-dimensional printed guides in total hip arthroplasty: A systematic review
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作者 Tim P Crone Bart M W Cornelissen +2 位作者 Jakob Van Oldenrijk Pieter Koen Bos Ewout S Veltman 《World Journal of Orthopedics》 2024年第7期660-667,共8页
BACKGROUND Acetabular component positioning in total hip arthroplasty(THA)is of key importance to ensure satisfactory post-operative outcomes and to minimize the risk of complications.The majority of acetabular compon... BACKGROUND Acetabular component positioning in total hip arthroplasty(THA)is of key importance to ensure satisfactory post-operative outcomes and to minimize the risk of complications.The majority of acetabular components are aligned freehand,without the use of navigation methods.Patient specific instruments(PSI)and three-dimensional(3D)printing of THA placement guides are increasingly used in primary THA to ensure optimal positioning.AIM To summarize the literature on 3D printing in THA and how they improve acetabular component alignment.METHODS PubMed was used to identify and access scientific studies reporting on different 3D printing methods used in THA.Eight studies with 236 hips in 228 patients were included.The studies could be divided into two main categories;3D printed models and 3D printed guides.RESULTS 3D printing in THA helped improve preoperative cup size planning and post-operative Harris hip scores between intervention and control groups(P=0.019,P=0.009).Otherwise,outcome measures were heterogeneous and thus difficult to compare.The overarching consensus between the studies is that the use of 3D guidance tools can assist in improving THA cup positioning and reduce the need for revision THA and the associated costs.CONCLUSION The implementation of 3D printing and PSI for primary THA can significantly improve the positioning accuracy of the acetabular cup component and reduce the number of complications caused by malpositioning. 展开更多
关键词 Total hip arthroplasty Three-dimensional printing Hip replacement surgery Three-dimensional planning Surgical guides
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Study of Axisymmetric Infinite Guide Lined with Locally Reacting Material without Flow Using DtN Operators
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作者 Boureima Ouedraogo Emmanuel Redon 《Open Journal of Applied Sciences》 2024年第2期572-588,共17页
The present work proposed a new method for the modeling by the finite element method of the acoustic propagation problems in infinite axisymmetric cylindrical guides lined with locally reacting absorbent materials wit... The present work proposed a new method for the modeling by the finite element method of the acoustic propagation problems in infinite axisymmetric cylindrical guides lined with locally reacting absorbent materials without flow. The method deals with the development of an efficient transparent boundary condition based on DtN operators. The method developed in this study is successfully applied to a straight axisymmetric lined guide by imposing a mode on one of the artificial boundaries of the truncated guide. The results are in good agreement with analytical solutions. Applying the method for a non-uniform axisymmetric lined guide which is a complex case, proved its effectiveness and the results compared to those of PML layers are in very good agreement. 展开更多
关键词 DtN Operator Axisymmetric Cylindrical guides Finite Element Method Modes
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The Path to Growth and Maturity for Young Students: Embracing Independence and Self- Reliance
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作者 Ruimin Chang Qin Zhao 《Journal of Contemporary Educational Research》 2024年第8期290-295,共6页
Young students are the future of our country and the hope of our nation.The healthy growth of young students must rely on independence and self-reliance.From the perspectives of family,society,and school,this article ... Young students are the future of our country and the hope of our nation.The healthy growth of young students must rely on independence and self-reliance.From the perspectives of family,society,and school,this article explores the cultivation of young students’spirit of independence and self-reliance,which should be grasped from three aspects:recognizing the situation,identifying the reasons,and taking effective measures. 展开更多
关键词 Young students SELF-RELIANCE independence PATH
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