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A comparative study on characteristics of retracted publications across different open access levels
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作者 Er-Te Zheng Hui-Zhen Fu 《Journal of Data and Information Science》 CSCD 2024年第2期22-40,共19页
Purpose:Recently,global science has shown an increasing open trend,however,the characteristics of research integrity of open access(OA)publications have rarely been studied.The aim of this study is to compare the char... Purpose:Recently,global science has shown an increasing open trend,however,the characteristics of research integrity of open access(OA)publications have rarely been studied.The aim of this study is to compare the characteristics of retracted articles across different OA levels and discover whether OA level influences the characteristics of retracted articles.Design/methodology/approach:The research conducted an analysis of 6,005 retracted publications between 2001 and 2020 from the Web of Science and Retraction Watch databases.These publications were categorized based on their OA levels,including Gold OA,Green OA,and non-OA.The study explored retraction rates,time lags and reasons within these categories.Findings:The findings of this research revealed distinct patterns in retraction rates among different OA levels.Publications with Gold OA demonstrated the highest retraction rate,followed by Green OA and non-OA.A comparison of retraction reasons between Gold OA and non-OA categories indicated similar proportions,while Green OA exhibited a higher proportion due to falsification and manipulation issues,along with a lower occurrence of plagiarism and authorship issues.The retraction time lag was shortest for Gold OA,followed by non-OA,and longest for Green OA.The prolonged retraction time for Green OA could be attributed to an atypical distribution of retraction reasons.A comparative study on characteristics of retracted publications across different open access levels Research limitations:There is no exploration of a wider range of OA levels,such as Hybrid OA and Bronze OA.Practical implications:The outcomes of this study suggest the need for increased attention to research integrity within the OA publications.The occurrences offalsification,manipulation,and ethical concerns within Green OA publications warrant attention from the scientific community.Originality/value:This study contributes to the understanding of research integrity in the realm of OA publications,shedding light on retraction patterns and reasons across different OA levels. 展开更多
关键词 Open access retracted publications Reasons for retraction retraction time lag BIBLIOMETRICS
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Amend:An integrated platform of retracted papers and concerned papers
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作者 Menghui Li Fuyou Chen +2 位作者 Sichao Tong Liying Yang Zhesi Shen 《Journal of Data and Information Science》 CSCD 2024年第2期41-55,共15页
Purpose:The notable increase in retraction papers has attracted considerable attention from diverse stakeholders.Various sources are now offering information related to research integrity,including concerns voiced on ... Purpose:The notable increase in retraction papers has attracted considerable attention from diverse stakeholders.Various sources are now offering information related to research integrity,including concerns voiced on social media,disclosed lists of paper mills,and retraction notices accessible through journal websites.However,despite the availability of such resources,there remains a lack of a unified platform to consolidate this information,thereby hindering efficient searching and cross-referencing.Thus,it is imperative to develop a comprehensive platform for retracted papers and related concerns.This article aims to introduce“Amend,”a platform designed to integrate information on research integrity from diverse sources.Design/methodology/approach:The Amend platform consolidates concerns and lists of problematic articles sourced from social media platforms(e.g.,PubPeer,For Better Science),retraction notices from journal websites,and citation databases(e.g.,Web of Science,CrossRef).Moreover,Amend includes investigation and punishment announcements released by administrative agencies(e.g.,NSFC,MOE,MOST,CAS).Each related paper is marked and can be traced back to its information source via a provided link.Furthermore,the Amend database incorporates various attributes of retracted articles,including citation topics,funding details,open access status,and more.The reasons for retraction are identified and classified as either academic misconduct or honest errors,with detailed subcategories provided for further clarity.Findings:Within the Amend platform,a total of 32,515 retracted papers indexed in SCI,SSCI,and ESCI between 1980 and 2023 were identified.Of these,26,620(81.87%)were associated with academic misconduct.The retraction rate stands at 6.64 per 10,000 articles.Notably,the retraction rate for non-gold open access articles significantly differs from that for gold open access articles,with this disparity progressively widening over the years.Furthermore,the reasons for retractions have shifted from traditional individual behaviors like falsification,fabrication,plagiarism,and duplication to more organized large-scale fraudulent practices,including Paper Mills,Fake Peer-review,and Artificial Intelligence Generated Content(AIGC).Research limitations:The Amend platform may not fully capture all retracted and concerning papers,thereby impacting its comprehensiveness.Additionally,inaccuracies in retraction notices may lead to errors in tagged reasons.Practical implications:Amend provides an integrated platform for stakeholders to enhance monitoring,analysis,and research on academic misconduct issues.Ultimately,the Amend database can contribute to upholding scientific integrity.Originality/value:This study introduces a globally integrated platform for retracted and concerning papers,along with a preliminary analysis of the evolutionary trends in retracted papers. 展开更多
关键词 Research Integrity retraction Rate Academic Misconduct Reasons for retraction Temporal Trends
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Using Flowable Composite as Gingival Retraction Cord in Prosthodontics Dentistry: Two Case Reports: A Dental Technique
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作者 Fahad Hussain Alqahtani 《Open Journal of Stomatology》 2024年第2期118-131,共14页
One of the most challenging factors affecting impression quality and good marginal fit is the gingival retraction method, which aims to separate the gingiva from the tooth to expose the finishing line of the prepared ... One of the most challenging factors affecting impression quality and good marginal fit is the gingival retraction method, which aims to separate the gingiva from the tooth to expose the finishing line of the prepared tooth. Bleeding and contamination from the crevicular fluid may compete for space with the impression material within the sulcus, leading to indistinct preparations and a lack of detail at the margin. In addition, such procedures might damage the PDL and cause permanent recession. Flowable composite cable, as opposed to traditional retraction cords, offers the proper marginal seal and visibility during the impression record because of its lower viscosity, improved adaptability, and elastic properties. The aim of this report is to present a brand-new, innovative method for controlling gingival hemorrhage in addition to the gingival retraction in restorative and prosthodontic treatment by utilizing a flowable composite during the final impression record procedure. In these case reports, the flowable composite cord technique is used instead of traditional gingival cords to modify and refine the gingival tissue before taking the traditional final impression or digital scan. Two cases were done for patients undergoing fixed prosthodontics and veneer treatment within a 2-year follow-up period. In addition, the flowable composite cord was used as temporary restoration before the final prosthetic cementation or under the provisional crowns. As a result, clean and healthy gingival tissues render cementation of the final prosthesis quicker and easier to perform. The patients in both cases claimed that their prosthodontic treatments, which involved the application of a flowable composite cord to temporarily retraction the gingiva, had produced good outcomes at the yearlong follow-up. In conclusion, the flowable composite cord technique is found to be a useful tool to improve the quality of impressions in fixed prosthodontics by providing excellent access for impression material to record fine details of the finish line of the prepared tooth structure, and to alter the inflamed tissue into a healthy tissue. 展开更多
关键词 Flowable Composite Gingival retraction Methods Impression Material Marginal Integrity Final Cementation
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Retraction note to:RNA-binding protein CPSF6 regulates IBSP to affect pyroptosis in gastric cancer
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作者 Xue-Jun Wang Yong Liu +2 位作者 Bin Ke Li Zhang Han Liang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2865-2866,共2页
The authors have decided to retract the article published on World J Gastrointest Oncol(2023)for further consideration due to data errors and some misunderstandings in communication.
关键词 retraction note
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Research misconduct in hospitals is spreading:A bibliometric analysis of retracted papers from Chinese university-affiliated hospitals 被引量:1
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作者 Zi-han Yuan Yi Liu 《Journal of Data and Information Science》 CSCD 2023年第4期84-101,共18页
Purpose: The number of retracted papers from Chinese university-affiliated hospitals is increasing, which has raised much concern. The aim of this study is to analyze the retracted papers from university-affiliated ho... Purpose: The number of retracted papers from Chinese university-affiliated hospitals is increasing, which has raised much concern. The aim of this study is to analyze the retracted papers from university-affiliated hospitals in China’s mainland from 2000 to 2021. Design/methodology/approach: Data for 1,031 retracted papers were identified from the Web of Science Core collection database. The information of the hospitals involved was obtained from their official websites. We analyzed the chronological changes, journal distribution, discipline distribution and retraction reasons for the retracted papers. The grade and geographic locations of the hospitals involved were explored as well.Findings: We found a rapid increase in the number of retracted papers, while the retraction time interval is decreasing. The main reasons for retraction are plagiarism/self-plagiarism(n=255), invalid data/images/conclusions(n=212), fake peer review(n=175) and honesty error(n=163). The disciplines are mainly distributed in oncology(n=320), pharmacology & pharmacy(n=198) and research & experimental medicine(n=166). About 43.8% of the retracted papers were from hospitals affiliated with prestigious universities. Research limitations: This study fails to differentiate between retractions due to honest error and retractions due to research misconduct. We believe that there is a fundamental difference between honest error retractions and misconduct retractions. Another limitation is that authors of the retracted papers have not been analyzed in this study.Practical implications: This study provides a reference for addressing research misconduct in Chinese university-affiliated hospitals. It is our recommendation that universities and hospitals should educate all their staff about the basic norms of research integrity, punish authors of scientific misconduct retracted papers, and reform the unreasonable evaluation system.Originality/value: Based on the analysis of retracted papers, this study further analyzes the characteristics of institutions of retracted papers, which may deepen the research on retracted papers and provide a new perspective to understand the retraction phenomenon. 展开更多
关键词 retracted papers retractION Research integrity Research misconduct Chinese university-affiliated hospitals
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Retraction note to:Beneficial effect of probiotics supplements in reflux esophagitis treated with esomeprazole:A randomized controlled trial 被引量:3
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作者 Qing-Hua Sun Hong-Yan Wang +2 位作者 Shi-Dong Sun Xin Zhang Han Zhang 《World Journal of Gastroenterology》 SCIE CAS 2023年第1期221-222,共2页
We have decided to retract the above article for further consideration due to a data labelling error.
关键词 retraction note
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Assessment of retracted papers,and their retraction notices,from a cancer journal associated with“paper mills” 被引量:1
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作者 Jaime A.Teixeira da Silva Serhii Nazarovets 《Journal of Data and Information Science》 CSCD 2023年第2期118-125,共8页
Cancer research is occasionally described as being in a reproducibility crisis.The cancer literature has ample papers retracted due to misconduct,including the use of paper mills,invalid authorship,or fake data.The ob... Cancer research is occasionally described as being in a reproducibility crisis.The cancer literature has ample papers retracted due to misconduct,including the use of paper mills,invalid authorship,or fake data.The objective of this paper was to gain an appreciation of the balance of retractions and associated retraction notices of 23 retracted Cancer Biotherapy and Radiopharmaceuticals papers associated with paper mills.By 23 March 2023,these retracted papers had already accumulated 287 citations according to Web of Science Core Collection,253 according to Scopus,and 365 according to Google Scholar,i.e.,metrically speaking,they were highly rewarded.All authors had an affiliation(71%being a hospital)in China.Most(12/21;57%)of corresponding authors had emails with a@163.com suffix.Four of the retraction notices(i.e.,17%)explicitly indicated paper mills as a reason for retraction although,in general,the retraction notices lacked details and background that could assist readers’understanding of the retractions. 展开更多
关键词 INDEXING ONCOLOGY Publishing history PUBMED retraction Notices TRANSPARENCY
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Efficacy of invisible advancement correction for mandibular retraction in adolescents based on Pancherz analysis 被引量:1
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作者 Lei Kong Xin-Qiang Liu 《World Journal of Clinical Cases》 SCIE 2023年第6期1299-1309,共11页
BACKGROUND Mandibular retraction is the main etiological mechanism of class II malocclusion in China and the subsequent distal molar relationship can cause functional discomfort in mastication,breathing and the tempor... BACKGROUND Mandibular retraction is the main etiological mechanism of class II malocclusion in China and the subsequent distal molar relationship can cause functional discomfort in mastication,breathing and the temporomandibular joint.The use of mandibular advancement(MA)devices has recently emerged as an adolescent mandibular retraction treatment;however,current studies regarding the effect thereof are relatively few,and there is lack of sufficient clinical support.AIM To investigate the clinical effect of invisalign MA on the treatment of mandibular retraction in adolescents.METHODS This study included 30 adolescent patients who underwent treatment with the MA appliances from December 2017 to June 2021.The lateral cephalometric data before and after treatment were collected and imported into Dolphin Imaging software.The changes were measured by linear measurement superimposed with lateral cephalometric trajectory based on the Pancherz technology.RESULTS There was no significant difference in the length and position of maxilla before and after the treatment.The position of the mandible moved 3.13 mm,the length increased 4.14 mm,the mandibular ramus length increased 4.09 mm,the body length increased 4.25 mm,and the position of the condyle moved 1.03 mm forward after treatment.Additionally,changes in the incisor sagittal position and labial inclination were observed.The position of the upper incisor point moved back 1.33 mm,without statistical difference,the inclination and tooth angle decreased by 3.44°and 4.06°,respectively;the position of the lower incisor point was moved 2.98 mm,and the inclination and tooth angle increased by 2.62°and 1.23°,respectively.Furthermore,changes in the incisor overjet and molar relationship were seen.Overjet decreased by 4.31 mm,of which 1.78 mm was due to dental factors,accounting for 41.3%of the effect as opposed to 58.7%due to skeletal factors.Molar relationship improved 3.87 mm,with 1.34 mm due to dental factors,and dental and skeletal factors were accounted for 34.6%and 65.4%of the effect,respectively.CONCLUSION For adolescent patients with mandible retraction,invisalign MA can effectively promote the mandible growth,and it was proven to be mainly due to skeletal effects. 展开更多
关键词 Mandibular retraction ADOLESCENT Pancherz technology Functional correction Invisible appliance Mandibular advancement
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Reliability analysis of retractable drill bit with air reverse circulation used for drilling while casing
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作者 WANG Minqi YIN Qilei +3 位作者 CHEN Baoyi QI Bo BO Kun CAO Pinlu 《Global Geology》 2023年第1期47-56,共10页
Casing-while-drilling(CWD)with down the hole(DTH)hammer drilling technology has been widely used in unconsolidated formations,due to its advantages in protecting the borehole wall,excellent rock cuttings capacity,and ... Casing-while-drilling(CWD)with down the hole(DTH)hammer drilling technology has been widely used in unconsolidated formations,due to its advantages in protecting the borehole wall,excellent rock cuttings capacity,and fast penetration rate in hard rock.As an important component of the CWD system,the structure of the retractable drill bit needs not only to ensure to form stronger reverse circulation,but also to be expandable or retractable as needed,otherwise the drill bit cannot be lift and put down smoothly in the casing,and may lead to drilling accidents.This paper developed a new type of reverse circulation DTH hammer drill bit used for CWD drilling technology.The retractable performance of this type of drill bit is studied using ADAMS software.The results show that it is smoothly expandable and retractable as designed under the conditions of the weight of the bit(WOB)of 0.5–2.0 t and the rotation speed of 30–60 r/min.To investigate the reverse circulation effect of the drill bit,Fluent software was used to simulate the flow characteristic inside it.The simulation results indicated that it can form strong reverse circulation,and the entrainment ratio h can reach 9.5%. 展开更多
关键词 DTH hammer drilling air reverse circulation casing-while-drilling retractable drill bit
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液压挖掘机斗杆内收流量分配节能设计
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作者 高韶坤 艾建军 《液压与气动》 北大核心 2024年第4期142-150,共9页
为解决小型挖掘机挖掘工况(正负载)下斗杆内收速度慢、系统压力高、存在溢流损失等问题,提出一种斗杆内收节能系统,挖掘工况下,使斗杆内收通过节能阀回油,即斗杆内收流量不再生时增大回油面积。给出了该节能系统工作原理和仿真参数,基于... 为解决小型挖掘机挖掘工况(正负载)下斗杆内收速度慢、系统压力高、存在溢流损失等问题,提出一种斗杆内收节能系统,挖掘工况下,使斗杆内收通过节能阀回油,即斗杆内收流量不再生时增大回油面积。给出了该节能系统工作原理和仿真参数,基于AMESim搭建了斗杆内收节能系统仿真模型,对比仿真了有无节能阀系统的斗杆内收速度、压力、流量等动态特性,分析了节能阀直径对斗杆内收动态特性的影响效果,进行了系统实际应用可行性分析,挖掘机整机测试有效验证了仿真结论。结果表明:引入节能阀,斗杆内收速度增加18%,斗杆油缸进油压力降低65%;节能阀直径对斗杆内收系统输出流量、回油总流量、系统压力影响不大;通过挖掘机整机测得斗杆内收速度提高19%。 展开更多
关键词 液压挖掘机 斗杆内收 流量分配 节能阀
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基于引力指数的地震应急物资调配方案研究
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作者 范熙伟 聂高众 +1 位作者 邓砚 李华玥 《中国应急救援》 2024年第3期44-49,54,共7页
震后应急物资和设备的科学、高效投送是地震应急救援的关键,本研究基于地震应急物资需求点和物资储备点吸引力指数模型,研究应急物资和设备在震后灾区的配置方案,其中应急物资需求点和应急物资储备点吸引力指数主要用于指示某个应急物... 震后应急物资和设备的科学、高效投送是地震应急救援的关键,本研究基于地震应急物资需求点和物资储备点吸引力指数模型,研究应急物资和设备在震后灾区的配置方案,其中应急物资需求点和应急物资储备点吸引力指数主要用于指示某个应急物资需求点即灾区应当从哪个应急物资储备点调配物资。通过计算距离指数和物资储备指数,计算灾区和18个应急物资储备库的吸引力指数,从而确定物资调配方案。最后以山西大同、北京、沈阳、云南昭通、河北张家口和上海为例,确定了最优调配物资储备点,表明本研究提出的方法可用于震后应急物资的调配。 展开更多
关键词 地震 应急物资 调配
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收放伞绳对十字型伞静态气动特性影响的数值模拟研究
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作者 胡俊 于菲 于勇 《北京理工大学学报》 EI CAS CSCD 北大核心 2024年第1期10-17,共8页
为研究十字型降落伞作为主动控制装置时,其可控性与气动特性的规律,建立了不同伞绳收缩比δ为0、10.0%、12.5%、15.0%、20.0%、25.0%时十字型伞无限质量充气的有限元模型,基于任意拉格朗日-欧拉方法进行数值模拟,分析了十字型降落伞收... 为研究十字型降落伞作为主动控制装置时,其可控性与气动特性的规律,建立了不同伞绳收缩比δ为0、10.0%、12.5%、15.0%、20.0%、25.0%时十字型伞无限质量充气的有限元模型,基于任意拉格朗日-欧拉方法进行数值模拟,分析了十字型降落伞收缩伞绳,引起伞面几何构型不对称对气动特性的影响.结果表明:不同攻角为0°、5°、10°时,十字型降落伞的平均阻力系数随伞绳收缩比δ的增大而减小;十字型伞的瞬时升力峰值随着伞绳收缩比δ的增加而增大,方向始终由伞绳收缩一侧指向另一侧,具有较强的时变特性. 展开更多
关键词 十字型降落伞 伞绳收缩 气动特性 数值模拟 任意拉格朗日欧拉方法
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基于充气薄膜的可展开帆板结构设计
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作者 张元勋 徐莉萍 +1 位作者 张晓敏 黄镐 《中国空间科学技术(中英文)》 CSCD 北大核心 2024年第2期30-39,共10页
充气薄膜结构具有质量轻、收纳比高的优势。通过理论分析及实验验证的方法,得到了充气薄膜管承载力矩与充气内压、管道内径、展开程度之间的映射关系。进一步通过“厚度包边”法处理二级展开帆板的厚度问题,设计了转动锁定、转动-滑移... 充气薄膜结构具有质量轻、收纳比高的优势。通过理论分析及实验验证的方法,得到了充气薄膜管承载力矩与充气内压、管道内径、展开程度之间的映射关系。进一步通过“厚度包边”法处理二级展开帆板的厚度问题,设计了转动锁定、转动-滑移锁定、搭接锁定连接结构,提出薄膜管驱动的二级可展开矩形帆板、圆形帆板以及百叶窗式矩形帆板三种大尺度可展开帆板结构形式,并进行展开状态的模态仿真,对比其模态振型。本设计可为大尺度充气可展开结构形式提供参考。 展开更多
关键词 薄膜展开 承载力矩 展开锁定 折展机构
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基于可伸缩型注意力机制的神经网络地震数据去噪方法
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作者 张敏 许一卓 易继东 《物探与化探》 CAS 2024年第4期1065-1075,共11页
地震资料中的随机噪声会影响地震数据的质量,从而影响后续处理与解释的准确性。传统去噪方法受先验条件的约束,效率低下,神经网络具有强大的特征提取能力,能够弥补这些缺点。然而,由于传统神经网络卷积核的局限性,可能会导致全局信息丢... 地震资料中的随机噪声会影响地震数据的质量,从而影响后续处理与解释的准确性。传统去噪方法受先验条件的约束,效率低下,神经网络具有强大的特征提取能力,能够弥补这些缺点。然而,由于传统神经网络卷积核的局限性,可能会导致全局信息丢失。为了克服这个缺点,本文在卷积神经网络(CNN)的基础上,添加了可伸缩型注意力机制。该机制在网络中同时呈现密集和稀疏两种类型的自注意力模块,这两种注意力模块交替使用可以显著增强神经网络的表现能力,扩大接受场。通过卷积层和注意力模块提取地震数据浅层特征和深层特征,结合CNN的局部建模能力和Transformer的全局建模能力,有利于提升网络的全局交互作用,增强其去除噪声和处理细节的能力。最后,合成和实际地震数据实验结果均表明,该方法相较于Unet和DnCNN,具有更好的噪声压制与保留地震数据有效信息的能力,可以大幅提高信噪比,为地震数据的处理和解释提供帮助。 展开更多
关键词 随机噪声 卷积神经网络 可伸缩型注意力机制 TRANSFORMER
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关于魔力弹簧的收缩时间和上端运动问题
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作者 于凤军 张希威 +2 位作者 汤振杰 鞠林 田俊龙 《大学物理》 2024年第5期13-18,共6页
针对有关魔力弹簧研究中的几个问题进行探讨和澄清.建立了预收缩力弹簧的模型,推出其形变规律.根据质心运动定理,导出这种弹簧自由下落时,收缩到原长所用的时间、其上端的运动方程和速度公式.研究表明,对于通常演示所用的魔力弹簧,在自... 针对有关魔力弹簧研究中的几个问题进行探讨和澄清.建立了预收缩力弹簧的模型,推出其形变规律.根据质心运动定理,导出这种弹簧自由下落时,收缩到原长所用的时间、其上端的运动方程和速度公式.研究表明,对于通常演示所用的魔力弹簧,在自由下落时的收缩阶段,其上端不是作匀速直线运动. 展开更多
关键词 魔力弹簧 预收缩力弹簧 收缩时间 质心运动定理
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电动工具塑件的复合二次抽芯注塑模具设计
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作者 赵利平 胡邓平 侯贤州 《塑料》 CAS CSCD 北大核心 2024年第3期44-49,共6页
根据电动工具结构件镂空的结构特点,结合其成型生产的技术要求,设计一副包含了三边侧向抽芯的复杂注塑模具。选择侧向复合二次抽芯机构解决塑件一侧倒扣和内扣组合结构的脱模问题,侧向复合二次抽芯结构中的内缩镶件机构设计精巧,模具空... 根据电动工具结构件镂空的结构特点,结合其成型生产的技术要求,设计一副包含了三边侧向抽芯的复杂注塑模具。选择侧向复合二次抽芯机构解决塑件一侧倒扣和内扣组合结构的脱模问题,侧向复合二次抽芯结构中的内缩镶件机构设计精巧,模具空间占用少,采用研磨工艺制作,使其尺寸精度达到IT5级;选择2个平滑块侧分型抽芯结构的方式脱出塑件另外两侧边的倒扣和主体胶位,充分利用滑块达到分步脱模的目的,同时,配合斜顶抽芯顶出机构的设计,有效解决了镂空结构状塑件容易粘模和顶出困难的难题。模具经过实际生产验证,结构的合理性、生产的顺畅性、品质的稳定性均达到模具批量生产的要求。 展开更多
关键词 镂空 侧向复合二次抽芯 组合结构 侧分型抽芯 斜顶抽芯 内缩镶件机构
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典型高被引撤稿论文的特征及期刊应对策略分析
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作者 李国琪 《江苏科技信息》 2024年第6期116-119,共4页
近年来,随着撤稿数量不断增加,如何应对引用撤稿论文行为是期刊无法回避的新问题。论文撤稿后仍被持续引用的情形并不少见,在知名、高影响因子期刊尤为明显。由于期刊和数据库对撤稿状态标注不规范或作者直接引用较早前下载版本而未重... 近年来,随着撤稿数量不断增加,如何应对引用撤稿论文行为是期刊无法回避的新问题。论文撤稿后仍被持续引用的情形并不少见,在知名、高影响因子期刊尤为明显。由于期刊和数据库对撤稿状态标注不规范或作者直接引用较早前下载版本而未重新核实出版状态,部分作者对引用撤稿论文不知情或未标明撤稿状态,期刊则对其潜在危害不够重视,同时也缺乏权威指南或建议可供借鉴。文章展示了撤稿观察近期公布的十大高被引撤稿论文的特征,建议综合考虑撤稿原因、引用动机及引用态度等因素,恰当应对引用撤稿论文行为,从而净化学术氛围、提升出版质量。 展开更多
关键词 撤稿论文 撤稿原因 引用动机 引用态度 学术期刊 对策
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结合STPA和DEMATEL-ISM的民机起落架收放系统风险研究
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作者 贾宝惠 韩文瑞 +2 位作者 肖海建 高源 陈怡凡 《安全与环境学报》 CAS CSCD 北大核心 2024年第8期2885-2894,共10页
为从系统整体角度完成对起落架收放系统的风险辨识和影响分析,将系统理论过程分析(Systematic Theory Process Analysis,STPA)与决策实验室分析-解释结构模型(Decision Making Trial and Evaluation Laboratory Interpretive Structural... 为从系统整体角度完成对起落架收放系统的风险辨识和影响分析,将系统理论过程分析(Systematic Theory Process Analysis,STPA)与决策实验室分析-解释结构模型(Decision Making Trial and Evaluation Laboratory Interpretive Structural Modeling,DEMATEL-ISM)相结合来开展分析。首先,定义事故和系统级危险,以民机进近阶段放下起落架为例,运用STPA完成对风险因素的系统化辨识;其次,基于最大平均熵减(Maximum Mean De-entropy,MMDE)算法帮助DEMATEL-ISM模型确定阈值,完成对风险因素影响的重要性分析并识别可能引发系统级危险的风险传递路径,据此挖掘关键致因场景,以给出风险预防建议。结果显示:线路性能退化或失效、位置作动控制组件(Position Action Control Unit,PACU)核心处理器故障为关键原因因素,收放作动筒作动异常、机组成员操作不当、起落架指示灯显示异常、起落架液压选择阀作动异常、PACU信息接收有误为关键结果因素,这些因素均涉及多条可能引发系统级危险的风险传递路径,应予以重点控制。 展开更多
关键词 安全工程 起落架收放系统 系统理论过程分析(STPA) 决策实验室分析法(DEMATEL) 解释结构模型(ISM) 关键因素 风险传递路径
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中深层煤炭地下气化的气化腔安全宽度计算方法 被引量:1
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作者 东振 任博 +7 位作者 陈艳鹏 赵宇峰 陈浩 陈姗姗 薛俊杰 张梦媛 易海洋 吴瀚琦 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第2期183-193,共11页
煤炭地下气化是目前温度最高(超过1200℃)的化石能源非常规开发方式,中深层(本文指埋深800~1500 m)煤炭地下气化在提高气化压力、降低地质安全风险方面优势明显,科学预测气化腔安全宽度对保障气化稳定运行十分重要,由于目前基于可控注... 煤炭地下气化是目前温度最高(超过1200℃)的化石能源非常规开发方式,中深层(本文指埋深800~1500 m)煤炭地下气化在提高气化压力、降低地质安全风险方面优势明显,科学预测气化腔安全宽度对保障气化稳定运行十分重要,由于目前基于可控注入点后退(CRIP)工艺的气化腔安全宽度计算方法尚未建立,为保证现场试验顺利实施,需要开展针对性研究。气化腔顶板“裸露”在气化腔后会受到高温影响,通过数值模拟方法研究了压应力约束条件下岩石内部热应力产生位置以及颗粒、基质热膨胀系数差异对热应力大小的影响规律,结合高温处理后的岩石电镜扫描结果,查明了高温下岩石热损伤机理。根据CRIP气化工艺造腔特点,建立了考虑高温影响的气化腔顶板薄板模型,结合“关键层”理论提出了气化腔安全宽度计算方法。研究表明:岩石热损伤是岩石物理化学反应与热应力互相促进、共同作用的结果,高温下岩石发生不规则变形,岩石热损伤引起的微观结构变化是导致岩石力学性质、物理性质变化的根本原因。岩石的最大拉张热应力出现在颗粒界面或热膨胀系数较小的颗粒中,颗粒与基质热膨胀系数比值在[0.01~1)时,最大拉张热应力随颗粒热膨胀系数减小而快速增加。泥岩加热到200℃时开始出现微裂隙;加热到400℃时裂隙发育更加明显,主要是沿颗粒边缘破裂;加热到600~800℃时,裂隙数量增多、尺寸变大;加热到1000℃时,除出现较大裂隙外,还产生了大量孔隙;1200℃时裂隙连通性明显增加,气孔发育较大。由于高温的影响,薄板模型的步距准数不再是定值,需要根据气化腔顶板热破坏范围与顶板硬岩层的空间位置关系确定具体数值。气化腔安全宽度受温度影响,在研究算例中,砂岩顶板在35、1000℃时安全宽度计算结果分别为34.3 m和14.1 m,相差达58.9%,泥岩顶板在35、1000℃时安全宽度计算结果分别为16.7 m和15.9 m,相差4.8%。最后从降低顶板垮落风险、有利于气化控制角度,提出了煤层纵向靶区位置的确定方法,当煤层厚度超过气化腔安全宽度一半时,建议将水平井纵向靶区设计在距离煤顶不超过气化腔安全宽度一半的位置。 展开更多
关键词 煤炭地下气化 可控注入点后退工艺 气化腔 热应力 热损伤 薄板模型 步距准数 安全宽度
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重大公共卫生事件下学术论文的科研诚信建设
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作者 许媛媛 崔云裳 +1 位作者 陈钰 张群 《医学与哲学》 北大核心 2024年第3期17-21,共5页
基于撤稿观察数据库,以生物医药领域COVID-19相关的撤稿论文为研究对象,分析撤稿论文中的学术不端现象,并就重大公共卫生事件背景下的学术论文科研诚信问题提出了一些思考与建议:探讨了重大公共卫生事件下科研诚信与学术论文出版速度的... 基于撤稿观察数据库,以生物医药领域COVID-19相关的撤稿论文为研究对象,分析撤稿论文中的学术不端现象,并就重大公共卫生事件背景下的学术论文科研诚信问题提出了一些思考与建议:探讨了重大公共卫生事件下科研诚信与学术论文出版速度的辨证关系,通过对学术论文的出版后再评价常态化完善科研诚信监督机制,通过加强学术论文数据管理和共享建立并完善科研诚信应急管理机制,重视生物医药领域的利益冲突问题,充分发挥学术期刊的公信力和传播优势解释学术争鸣,以及进一步夯实我国学术论文科研诚信建设。 展开更多
关键词 撤稿 学术论文 新型冠状病毒感染 科研诚信
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