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基于SLA 3D打印模型内部支撑的轻量化结构设计研究
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作者 赵军 《机电产品开发与创新》 2026年第1期55-57,68,共4页
本文针对SLA 3D打印技术中支撑结构材料浪费、后处理复杂、零件重量增加及力学性能不足等问题,研究提出一种基于蜂窝仿生原理的结构设计与工艺约束驱动的轻量化结构优化方法。通过构建螺旋蜂窝结构与分形树状自适应支撑网络,实现了模型... 本文针对SLA 3D打印技术中支撑结构材料浪费、后处理复杂、零件重量增加及力学性能不足等问题,研究提出一种基于蜂窝仿生原理的结构设计与工艺约束驱动的轻量化结构优化方法。通过构建螺旋蜂窝结构与分形树状自适应支撑网络,实现了模型内部自支撑特性与力学性能的协同优化。该方法突破了传统镂空结构自支撑性差与材料效率低的瓶颈,为复杂模型的跨尺度轻量化提供了新解决方案。 展开更多
关键词 sla 3D打印 模型 自支撑结构 轻量化设计
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基于多维SLA模型的时空网差异化服务机制的设计与应用
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作者 彭家骏 黄云飞 +3 位作者 麦磊鑫 罗东 高嘉和 李建林 《广东通信技术》 2026年第1期37-42,共6页
随着数字化时代的深入发展,在智能交通、物流管理等众多行业对时空服务提出了更高的要求,用户需求的日益多样化给时空网服务带来了诸多挑战。研究时空网差异化服务机制旨在有效满足不同用户的个性化需求,提升时空服务的质量与用户满意... 随着数字化时代的深入发展,在智能交通、物流管理等众多行业对时空服务提出了更高的要求,用户需求的日益多样化给时空网服务带来了诸多挑战。研究时空网差异化服务机制旨在有效满足不同用户的个性化需求,提升时空服务的质量与用户满意度。本研究采用基于多维SLA模型的方法,深入剖析多维SLA模型的概念、构成要素及优势,并在此基础上,针对不同场景下的用户需求特点,制定基于多维SLA模型的服务策略,构建差异化服务机制实现流程,多维SLA模型能够精准匹配用户多样化需求,实现服务在质量、响应时间、成本等多维度的差异化。提出的研究成果在理论层面丰富了时空服务领域的差异化服务机制,在实践方面为时空网服务提供优化服务策略、提升服务水平提供了有效参考,有助于推动时空位置服务领域的高质量发展。 展开更多
关键词 时空服务 多维sla模型 差异化服务机制 服务质量
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Review of heterogeneous nucleation to microstructure refinement in steel induced by second phase
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作者 Zi-Yi Ge Chuang Feng +4 位作者 Yong-Kun Yang Ji Zhou Guo-Xing Qiu Xiao-Ming Li Dong-Ping Zhan 《Journal of Iron and Steel Research International》 2026年第1期311-328,共18页
Heterogeneous nucleation,characterized by its low nucleation barrier and controllable nucleation sites,has been widely employed to manipulate the microstructures and properties of metallic materials.In recent years,th... Heterogeneous nucleation,characterized by its low nucleation barrier and controllable nucleation sites,has been widely employed to manipulate the microstructures and properties of metallic materials.In recent years,the dispersion of inclusions,carbides,and microstructure refinement in steel have emerged as one of the key research directions in the development of high-quality steel.The current research status regarding the regulation of inclusions,carbides,and microstructures in steel through heterogeneous nucleation are reviewed.The key points and challenges in refining the second phase and microstructure in steel using inclusion particles are highlighted,aiming to provide inspiration and references for future scholars.Deoxidized inclusions,when refined and dispersed,exhibit favorable lattice matching with second phases(e.g.,nitrides,sulfides,carbides)in steel.This characteristic serves as the fundamental mechanism for achieving refinement of the second phase.Concurrently,the solid-solution alloying effect from deoxidizing metals contributes to second-phase refinement,an aspect that requires prioritized investigation.In addition to the single heterogeneous nucleation refinement effect,the two-stage heterogeneous nucleation refinement of the second phase and microstructure offers a new approach for follow-up research.Notably,second-phase particles added as heterogeneous nucleation sites via external addition often require surface modification to ensure their stable retention in steel at high temperatures,which remains a major challenge restricting the widespread application of this method.Currently,the explanation of heterogeneous nucleation phenomena primarily relies on empirical calculations of lattice mismatch between the substrate and the nucleating phase,which cannot fully elucidate the quantitative relationship on the interface between the substrate and the nucleation phase.On this basis,quantifying the electronic structure and nucleation barrier at the interface between the substrate and the nucleation phase is a critical direction worthy of increased attention in the future. 展开更多
关键词 Heterogeneous nucleation Inclusion metallurgy INTERFACE second phase MICROSTRUCTURE
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Phasemeter based on second harmonic signal filter for space-based gravitational wave detection
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作者 Zheng Fan Zhu Li +7 位作者 Xiangqing Huang Yurong Liang Yu Song Maomao Fan Huizong Duan Siyuan Peng Shanqing Yang Liangcheng Tu 《Chinese Physics B》 2026年第1期159-168,共10页
The space gravitational wave detection aims to detect gravitational waves in the mHz band in order to study supermassive black hole mergers,galaxy evolution and the structure of the early universe.One of its core payl... The space gravitational wave detection aims to detect gravitational waves in the mHz band in order to study supermassive black hole mergers,galaxy evolution and the structure of the early universe.One of its core payloads is a transponder-type interstellar laser interferometer,designed to measure relative displacement changes at the pico-meter level.Among its components,phasemeter is tasked with extracting the phase and frequency of the interference signal.Currently,phase-locked loop(PLL)phasemeters are commonly employed.However,the second harmonic signal generated by the mixer can restrict both the dynamic range and phase measurement accuracy of the phasemeter.This paper analyzes the interstellar laser interferometer and the impact of the second harmonic signal on the phasemeter's performance.To address these challenges,a phasemeter incorporating a second harmonic signal filter is proposed.This new design mitigates second harmonic disturbances within the phasemeter's bandwidth by dynamically adjusting the filter's cutoff frequency to track the input signal frequency,thereby suppressing the second harmonic signal in real time.Theoretical and simulation analyses demonstrate that the proposed phasemeter with a second harmonic filter significantly enhances the dynamic range.Finally,experimental results verify that the phasemeter can achieve the tracking of sudden frequency changes up to4.8 MHz. 展开更多
关键词 laser interferometer phasemeter second harmonic signal dynamic range
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Rediscovering Analytical Rigor in Traditional Economic Thought:The“Second Integration”and the Making of a Chinese School of Economics
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作者 Cheng Lin Zhou Rui Chen Xudong 《China Economist》 2026年第1期54-90,共37页
Does traditional Chinese economic thought possess genuine analytical rigor?This question lies at the heart of any serious evaluation of its theoretical value and historical significance.It also matters for understandi... Does traditional Chinese economic thought possess genuine analytical rigor?This question lies at the heart of any serious evaluation of its theoretical value and historical significance.It also matters for understanding how best to preserve,build on its remarkable achievements,and develop its intellectual legacy.Critics such as Schumpeter and Taylor have long argued that the economic reasoning found in ancient China cannot compare with that of classical Greece or medieval Europe.Yet this view often reflects the narrow assumptions of mainstream economics,defining analysis almost entirely in terms of market exchange.As a result,it tends to overlook traditions built around statecraft,governance,and the management of economic order.A careful re-examination and Sino-Western comparative analysis of key thinkers-including Mencius,Guanzi,and Sima Qian-tells a different story.Rooted in China’s distinctive cultural and philosophical heritage,traditional Chinese economic thought not only contains the analytical dimensions(as defined by Schumpeter)but also displays a broader and more diverse set of economic reasoning.Notably,its systematic depth and intellectual precision were,in many respects,remarkably advanced.Therefore,advancing the construction of a Chinese school of economics in the new era under the framework of the“Second Integration”,i.e.,integrating the basic tenets of Marxism with China’s fine traditional culture,should,and indeed can draw essential insights from this analytical tradition. 展开更多
关键词 traditional Chinese economic thought analytical rigor second Integration Chinese economics
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Analysis of Second Language Acquisition in Lost in Translation a Life in a New Language from the Perspective of Sociolinguistics
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作者 蒋馨 《海外英语》 2013年第19期186-187,共2页
Eva Hoffman’s Lost in Translation:A life in a New Language is prominent in that it spares no effort elaborating on the author’s personal experience in acquiring her second language(L2)English from the view of sociol... Eva Hoffman’s Lost in Translation:A life in a New Language is prominent in that it spares no effort elaborating on the author’s personal experience in acquiring her second language(L2)English from the view of sociolinguistics.In this vein,by in vestigating the underlined relationship between language learners’cultural identity and language identity from the perspective of sociolinguistics,the paper aims to explore the possibilities of assisting L2 learners reach a balance in their biological,cultural,so cial,and psychological domains of life. 展开更多
关键词 second language ACQUISITION IDENTITY sociolinguist
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Translating new data to the daily practice in second line treatment of renal cell carcinoma:The role of tumor growth rate 被引量:1
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作者 Enrique Grande Olga Martínez-Sáez +1 位作者 Pablo Gajate-Borau Teresa Alonso-Gordoa 《World Journal of Clinical Oncology》 CAS 2017年第2期100-105,共6页
The therapeutic options for patients with metastatic renal cell carcinoma(mRCC) have completely changed during the last ten years. With the sequential use of targeted therapies, median overall survival has increased i... The therapeutic options for patients with metastatic renal cell carcinoma(mRCC) have completely changed during the last ten years. With the sequential use of targeted therapies, median overall survival has increased in daily practice and now it is not uncommon to see patients surviving kidney cancer for more than four to five years. Once treatment fails with the first line targeted therapy, head to head comparisons have shown that cabozantinib, nivolumab and the combination of lenvatinib plus everolimus are more effective than everolimus alone and that axitinib is more active than sorafenib. Unfortunately, it is very unlikely that we will ever have prospective data comparing the activity of axitinib, cabozantinib, lenvatinib or nivolumab. It is frustrating to observe the lack of biomarkers that we have in this field, thus there is no firm recommendation about the optimal sequence of treatment in the second line. In the absence of reliable biomarkers, there are several clinical endpoints that can help physicians to make decisions for an individual patient, such as the tumor burden, the expected response rate and the time to achieve the response to each agent, the prior response to the agent administered, the toxicity profile of the different compounds and patient preference. Here, we propose the introduction of the tumor-growth rate(TGR) during first-line treatment as a new tool to be used to select the second line strategy in m RCC. The rapidness of TGR before the onset of the treatment reflects the variability between patients in terms of tumor growth kinetics and it could be a surrogate marker of tumor aggressiveness that may guide treatment decisions. 展开更多
关键词 AXITINIB EVEROLIMUS Cabozantinib Kidney cancer Nivolumab RENAL cell Sequence second line SORAFENIB TUMOR-GROWTH rate
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ON THE COMPLETE 2-DIMENSIONALλ-TRANSLATORS WITH A SECOND FUNDAMENTAL FORM OF CONSTANT LENGTH
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作者 Xingxiao LI Ruina QIAO Yangyang LIU 《Acta Mathematica Scientia》 SCIE CSCD 2020年第6期1897-1914,共18页
In this article we study the two-dimensional completeλ-translators immersed in the Euclidean space R^3 and Minkovski space R1^ 3.We obtain two classification theorems:one for two-dimensional completeλ-translators x:... In this article we study the two-dimensional completeλ-translators immersed in the Euclidean space R^3 and Minkovski space R1^ 3.We obtain two classification theorems:one for two-dimensional completeλ-translators x:M 2→R^3 and one for two-dimensional complete space-likeλ-translators x:M 2→R1^3,with a second fundamental form of constant length. 展开更多
关键词 singular solution mean curvature flow second fundamental form λ-translator classification
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The Second International Conference on HSLA Steels
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《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第9期224-225,共2页
GENERAL INFORMATIONThe Chinese Society of Metals is pleased to announcethat The Second International Conference on HSLASteels(HSEA’90)will be held in Beijing,China inOctober 1990.Much progress in research and devel-o... GENERAL INFORMATIONThe Chinese Society of Metals is pleased to announcethat The Second International Conference on HSLASteels(HSEA’90)will be held in Beijing,China inOctober 1990.Much progress in research and devel-opment of HSLA steels has been achieved by theworld’s metallurgical and materials community sincethe previous International Conference HSLA Steels’85 was held in Beijing,The aim of the conference isto review and to consolidate the scientific,metallurgical,and economical results and to assessthe future trend of development in the fields. 展开更多
关键词 Hsla MET The second International Conference on Hsla Steels
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Preliminary Announcement for the Second International Conference on HSLA Steels
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《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1989年第2期140-141,共2页
General Information The Chinese Society of Metals ispleased to announce that The SecondInternational Conference on HSLA Steels(HSLA ’90) will be held in Beijing, Chinain October, 1990. Much progress in researchand de... General Information The Chinese Society of Metals ispleased to announce that The SecondInternational Conference on HSLA Steels(HSLA ’90) will be held in Beijing, Chinain October, 1990. Much progress in researchand development of HSLA steels has beenachieved by the world’s metallurgical andmaterials community since the previousInternational Conference HSLA Steels ’85 展开更多
关键词 Hsla Preliminary Announcement for the second International Conference on Hsla Steels
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二语写作研究的现状、反思与展望——基于Journal of Second Language Writing近十年载文分析
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作者 孙云帆 孙玲 《西部学刊》 2025年第5期164-168,共5页
二语写作是二语习得研究领域的重要组成部分。运用CiteSpace软件对近十年发表在Journal of Second Language Writing的231篇实证研究论文进行可视化分析,研究发现:二语写作研究整体呈波动性上升趋势,研究规模较为稳定,研究关注度逐渐提... 二语写作是二语习得研究领域的重要组成部分。运用CiteSpace软件对近十年发表在Journal of Second Language Writing的231篇实证研究论文进行可视化分析,研究发现:二语写作研究整体呈波动性上升趋势,研究规模较为稳定,研究关注度逐渐提升;二语写作研究领域暂未形成明显的核心作者和机构的合作网络;研究主题主要聚焦二语写作教学方法的多元化、二语写作反馈的多焦点、二语写作评估与测试的科学化,以及学习者个体差异的多维影响等方面。基于此,提出未来该领域发展需加强学者、机构之间的相互合作;关注个体学习者写作过程的认知特征与情感因素,尤其重视青少年二语学习过程的研究;扩大二语写作纵向研究规模,推动研究的深入发展。 展开更多
关键词 二语写作研究 Journal of second Language Writing 可视化分析 现状 反思与展望
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The Role and Implication of Motivation in Second Language Acquisition(SLA)
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作者 李佩绮 《海外英语》 2018年第2期240-241,248,共3页
Motivation is one of the most important factors that affect foreign language learning.As it is affected by various factors,it becomes very complicated. Therefore, it is of great significance for foreign language teach... Motivation is one of the most important factors that affect foreign language learning.As it is affected by various factors,it becomes very complicated. Therefore, it is of great significance for foreign language teachers to explore how to motivate their students to become autonomous learners based on the overview of motivation studies in foreign language learning. This paper analyzes motivation factors on influencing learners in foreign language learning and explores some suggestions for motivating learner's learning. 展开更多
关键词 MOTIVATION second language acquisition STRATEGY
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The SLA (Second Law Analysis) in Convective Heat Transfer Processes
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作者 Heinz Herwig 《Journal of Energy and Power Engineering》 2016年第5期283-286,共4页
In all convective heat transfer situations, losses occur in the flow field (by dissipation) as well as in the temperature field (by conduction). Typically these losses are more or less quantified by the friction f... In all convective heat transfer situations, losses occur in the flow field (by dissipation) as well as in the temperature field (by conduction). Typically these losses are more or less quantified by the friction factorfwith respect to losses in the flow field, and the Nusselt number Nu for the heat transfer quality. Assessing the process of convective heat transfer as a whole, then becomes problematic because two different non-dimensional quantities, f and Nu, have to be combined somehow. From a thermodynamics point of view, there is a reasonable alternative: Since all losses become manifest in corresponding entropy generation rates, these rates are determined in the velocity as well as in the temperature field. Based on the integration of the entropy generation fields, an energy devaluation number is introduced. It basically determines how much oftbe so-called entropic potential of the energy involved in a convective heat transfer process is used within it. This approach is called SLA (second law analysis). 展开更多
关键词 second law analysis energy devaluation number entropic potential.
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The Second International Conference on HSLA Steels——Beijing,China,October 1990 Organized by THE CHINESE SOCIETY OF METALS
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《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第2期160-161,共2页
GENERAL INFORMATIONThe Chinese Society of Metals is pleased to announcethat The Second International Conference on HSLASteels (HSLA’90) will be held in Beijing,China inOctober 1990.Much progress in research and devel... GENERAL INFORMATIONThe Chinese Society of Metals is pleased to announcethat The Second International Conference on HSLASteels (HSLA’90) will be held in Beijing,China inOctober 1990.Much progress in research and devel-opment of HSLA steels has been achieved by theworld’s metallurgical and materials community since 展开更多
关键词 Hsla The second International Conference on Hsla Steels Beijing China October 1990 Organized by THE CHINESE SOCIETY OF METALS
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The Second International Conference on HSLA Steels Beijing,China,October 1990 Organized by THE CHINESE SOCIETY OF METALS
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《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第1期81-82,共2页
GENERAL INFORMATIONThe Chinese Society of Metals is pleased to announcethat The Second International Conference on HSLASteels(HSLA’90)will be held in Beijing,China inOctober 1990.Much progress in research and devel-o... GENERAL INFORMATIONThe Chinese Society of Metals is pleased to announcethat The Second International Conference on HSLASteels(HSLA’90)will be held in Beijing,China inOctober 1990.Much progress in research and devel-opment of HSLA steels has been achieved by theworld’s metallurgical and materials community since 展开更多
关键词 Hsla The second International Conference on Hsla Steels Beijing China October 1990 Organized by THE CHINESE SOCIETY OF METALS
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Second chance in fertility: a comprehensive narrative review of redo micro-TESE outcomes after initial failure 被引量:1
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作者 Haitham Elbardisi Emre Bakircioglu +1 位作者 Wen Liu Darren Katz 《Asian Journal of Andrology》 2025年第3期409-415,共7页
When microdissection testicular sperm extraction(micro-TESE)fails,a redo procedure may be the only option for patients who want a biological child.However,there are many gaps of knowledge surrounding the procedure,whi... When microdissection testicular sperm extraction(micro-TESE)fails,a redo procedure may be the only option for patients who want a biological child.However,there are many gaps of knowledge surrounding the procedure,which need to be addressed to help clinicians and patients make informed decisions.This review explores redo micro-TESE in the context of nonobstructive azoospermia(NOA).Literature was searched using Google Scholar,Medline,and PubMed.Search terms were“NOA”AND“second microdissection testicular sperm extractions”AND“redo microdissection testicles sperm extraction”AND“repeat microdissection testicular sperm extractions”AND“failed microdissection testicular sperm extractions”AND“salvage microdissection testicular sperm extractions”.Only original articles in English were included.A total of nine articles were included,consisting of four retrospective and five prospective studies.The time gap between the first and second micro-TESE varied from 6 months to 24 months.Most of the included studies reported successful surgical sperm retrieval(SSR)in the second micro-TESE in the range of 10%–21%,except in one study where it reached 42%.It has not been presented any definitive information about the use of hormonal treatment or the benefit of varicocelectomy prior to the second micro-TESE.Patients with hypospermatogenesis and Klinefelter syndrome(KS)had the highest chance of success in redo surgery.In conclusion,redo micro-TESE following a negative procedure can lead to sperm recovery in 10%–21%.Patients with hypospermatogenesis and KS have a higher chance of success.There is no enough evidence to conclude which is the best hormonal stimulation if any before a redo surgery. 展开更多
关键词 nonobstructive azoospermia redo micro-TESE repeat micro-TESE salvage micro-TESE second micro-TESE
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A Study on the Importance of Language Input in Second Language Acquisition(SLA)
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作者 闵瑞华 《海外英语》 2020年第23期275-277,284,共4页
Input theory as a theoretical foundation in language teaching plays an important role in SLA.Though a wealth of re⁃search has been done by linguists to demonstrate the importance of language input in SLA,little has be... Input theory as a theoretical foundation in language teaching plays an important role in SLA.Though a wealth of re⁃search has been done by linguists to demonstrate the importance of language input in SLA,little has been written about the type and amount of language input for successful SLA,especially its processing model while acquiring a second language.This paper first discusses the Krashen’s input hypothesis in language learning,and then an introduction to Chaudron’s processing model of in⁃put is made.In the final part,the author explains the acquisition process based on word acquisition and grammar acquisition and concludes that in the process of acquiring a second language,the language learners reconstruct a new cognitive model by taking in consistent comprehensible language input. 展开更多
关键词 language input sla processing model of input acquisition process
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Expert consensus on peri-implant keratinized mucosa augmentation at second-stage surgery 被引量:1
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作者 Shiwen Zhang Rui Sheng +26 位作者 Zhen Fan Fang Wang Ping Di Junyu Shi Duohong Zou Dehua Li Yufeng Zhang Zhuofan Chen Guoli Yang Wei Geng Lin Wang Jian Zhang Yuanding Huang Baohong Zhao Chunbo Tang Dong Wu Shulan Xu Cheng Yang Yongbin Mou Jiacai He Xingmei Yang Zhen Tan Xiaoxiao Cai Jiang Chen Hongchang Lai Zuolin Wang Quan Yuan 《International Journal of Oral Science》 2025年第5期608-616,共9页
Peri-implant keratinized mucosa(PIKM)augmentation refers to surgical procedures aimed at increasing the width of PIKM.Consensus reports emphasize the necessity of maintaining a minimum width of PIKM to ensure long-ter... Peri-implant keratinized mucosa(PIKM)augmentation refers to surgical procedures aimed at increasing the width of PIKM.Consensus reports emphasize the necessity of maintaining a minimum width of PIKM to ensure long-term peri-implant health.Currently,several surgical techniques have been validated for their effectiveness in increasing PIKM.However,the selection and application of PIKM augmentation methods may present challenges for dental practitioners due to heterogeneity in surgical techniques,variations in clinical scenarios,and anatomical differences.Therefore,clear guidelines and considerations for PIKM augmentation are needed.This expert consensus focuses on the commonly employed surgical techniques for PIKM augmentation and the factors influencing their selection at second-stage surgery.It aims to establish a standardized framework for assessing,planning,and executing PIKM augmentation procedures,with the goal of offering evidence-based guidance to enhance the predictability and success of PIKM augmentation. 展开更多
关键词 surgical procedures second stage surgery surgical techniques heterogeneity dental practitioners peri implant keratinized mucosa augmentation surgical techniquesvariations
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CLIL-SLA融合模型的大学英语教学改革实践与评价
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作者 姜雪 《哈尔滨学院学报》 2025年第8期95-99,共5页
全球化背景下,大学英语教学亟需突破传统模式局限,培养具有专业素养与跨文化交际能力的复合型人才。然而,单一教学模式(如CLIL)或理论(如SLA)均难以满足复合型人才培养的综合需求。为此,本研究创新性构建了CLIL-SLA融合框架,并以具体课... 全球化背景下,大学英语教学亟需突破传统模式局限,培养具有专业素养与跨文化交际能力的复合型人才。然而,单一教学模式(如CLIL)或理论(如SLA)均难以满足复合型人才培养的综合需求。为此,本研究创新性构建了CLIL-SLA融合框架,并以具体课程为例开展实证研究,探讨该框架指导下的大学英语教学改革实践与效果评估。最后基于研究结论提出了具体的优化策略,以期为深化大学英语教学改革、培养国际视野人才提供可推广的实践范式。 展开更多
关键词 CLIL sla 大学英语 教学改革 效果
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